diff options
Diffstat (limited to 'lib/ssh/doc/src')
| -rw-r--r-- | lib/ssh/doc/src/Makefile | 56 | ||||
| -rw-r--r-- | lib/ssh/doc/src/SSH_protocols.png | bin | 0 -> 15381 bytes | |||
| -rw-r--r-- | lib/ssh/doc/src/book.xml | 26 | ||||
| -rw-r--r-- | lib/ssh/doc/src/fascicules.xml | 5 | ||||
| -rw-r--r-- | lib/ssh/doc/src/introduction.xml | 204 | ||||
| -rw-r--r-- | lib/ssh/doc/src/notes.xml | 1835 | ||||
| -rw-r--r-- | lib/ssh/doc/src/part_notes.xml | 23 | ||||
| -rw-r--r-- | lib/ssh/doc/src/ref_man.xml | 36 | ||||
| -rw-r--r-- | lib/ssh/doc/src/ssh.xml | 799 | ||||
| -rw-r--r-- | lib/ssh/doc/src/ssh_app.xml | 319 | ||||
| -rw-r--r-- | lib/ssh/doc/src/ssh_channel.xml | 531 | ||||
| -rw-r--r-- | lib/ssh/doc/src/ssh_client_key_api.xml | 138 | ||||
| -rw-r--r-- | lib/ssh/doc/src/ssh_connection.xml | 508 | ||||
| -rw-r--r-- | lib/ssh/doc/src/ssh_protocol.xml | 147 | ||||
| -rw-r--r-- | lib/ssh/doc/src/ssh_server_key_api.xml | 107 | ||||
| -rw-r--r-- | lib/ssh/doc/src/ssh_sftp.xml | 711 | ||||
| -rw-r--r-- | lib/ssh/doc/src/ssh_sftpd.xml | 104 | ||||
| -rw-r--r-- | lib/ssh/doc/src/user_guide.gif | bin | 1581 -> 0 bytes | |||
| -rw-r--r-- | lib/ssh/doc/src/usersguide.xml | 39 | ||||
| -rw-r--r-- | lib/ssh/doc/src/using_ssh.xml | 390 |
20 files changed, 4913 insertions, 1065 deletions
diff --git a/lib/ssh/doc/src/Makefile b/lib/ssh/doc/src/Makefile index da99c4ea0f..a759854da4 100644 --- a/lib/ssh/doc/src/Makefile +++ b/lib/ssh/doc/src/Makefile @@ -1,18 +1,19 @@ # # %CopyrightBegin% # -# Copyright Ericsson AB 2004-2012. All Rights Reserved. +# Copyright Ericsson AB 2004-2016. All Rights Reserved. # -# The contents of this file are subject to the Erlang Public License, -# Version 1.1, (the "License"); you may not use this file except in -# compliance with the License. You should have received a copy of the -# Erlang Public License along with this software. If not, it can be -# retrieved online at http://www.erlang.org/. +# Licensed under the Apache License, Version 2.0 (the "License"); +# you may not use this file except in compliance with the License. +# You may obtain a copy of the License at # -# Software distributed under the License is distributed on an "AS IS" -# basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See -# the License for the specific language governing rights and limitations -# under the License. +# http://www.apache.org/licenses/LICENSE-2.0 +# +# Unless required by applicable law or agreed to in writing, software +# distributed under the License is distributed on an "AS IS" BASIS, +# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +# See the License for the specific language governing permissions and +# limitations under the License. # # %CopyrightEnd% # @@ -37,21 +38,30 @@ RELSYSDIR = $(RELEASE_PATH)/lib/$(APPLICATION)-$(VSN) # Target Specs # ---------------------------------------------------- XML_APPLICATION_FILES = ref_man.xml -XML_REF3_FILES = \ - ssh.xml \ +XML_REF3_FILES = ssh.xml \ ssh_channel.xml \ - ssh_connection.xml\ + ssh_connection.xml \ + ssh_client_key_api.xml \ + ssh_server_key_api.xml \ ssh_sftp.xml \ ssh_sftpd.xml \ -XML_PART_FILES = part_notes.xml -XML_CHAPTER_FILES = notes.xml +XML_REF6_FILES = ssh_app.xml + +XML_PART_FILES = part_notes.xml \ + usersguide.xml +XML_CHAPTER_FILES = notes.xml \ + introduction.xml \ + ssh_protocol.xml \ + using_ssh.xml BOOK_FILES = book.xml -XML_FILES = $(BOOK_FILES) $(XML_APPLICATION_FILES) $(XML_REF3_FILES) \ +XML_FILES = $(BOOK_FILES) $(XML_APPLICATION_FILES) $(XML_REF3_FILES) $(XML_REF6_FILES)\ $(XML_PART_FILES) $(XML_CHAPTER_FILES) +IMAGE_FILES = SSH_protocols.png + # ---------------------------------------------------- HTML_FILES = $(XML_APPLICATION_FILES:%.xml=$(HTMLDIR)/%.html) \ @@ -62,10 +72,12 @@ EXTRA_FILES = \ $(DEFAULT_GIF_FILES) \ $(DEFAULT_HTML_FILES) \ $(XML_REF3_FILES:%.xml=$(HTMLDIR)/%.html) \ + $(XML_REF6_FILES:%.xml=$(HTMLDIR)/%.html) \ $(XML_CHAPTER_FILES:%.xml=$(HTMLDIR)/%.html) MAN3_FILES = $(XML_REF3_FILES:%.xml=$(MAN3DIR)/%.3) +MAN6_FILES = $(XML_REF6_FILES:%_app.xml=$(MAN6DIR)/%.6) HTML_REF_MAN_FILE = $(HTMLDIR)/index.html @@ -80,16 +92,19 @@ DVIPS_FLAGS += # ---------------------------------------------------- # Targets # ---------------------------------------------------- -$(HTMLDIR)/%.gif: %.gif +$(HTMLDIR)/%.png: %.png $(INSTALL_DATA) $< $@ docs: pdf html man $(TOP_PDF_FILE): $(XML_FILES) +images: $(IMAGE_FILES:%=$(HTMLDIR)/%) + pdf: $(TOP_PDF_FILE) -html: $(HTML_REF_MAN_FILE) +html: images $(HTML_REF_MAN_FILE) + clean clean_docs: rm -rf $(HTMLDIR)/* @@ -97,7 +112,7 @@ clean clean_docs: rm -f $(TOP_PDF_FILE) $(TOP_PDF_FILE:%.pdf=%.fo) rm -f errs core *~ -man: $(MAN3_FILES) +man: $(MAN3_FILES) $(MAN6_FILES) debug opt: @@ -117,5 +132,8 @@ release_docs_spec: docs $(INSTALL_DATA) $(INFO_FILE) "$(RELSYSDIR)" $(INSTALL_DIR) "$(RELEASE_PATH)/man/man3" $(INSTALL_DATA) $(MAN3DIR)/* "$(RELEASE_PATH)/man/man3" + $(INSTALL_DIR) "$(RELEASE_PATH)/man/man6" + $(INSTALL_DATA) $(MAN6_FILES) "$(RELEASE_PATH)/man/man6" + release_spec: diff --git a/lib/ssh/doc/src/SSH_protocols.png b/lib/ssh/doc/src/SSH_protocols.png Binary files differnew file mode 100644 index 0000000000..145c96c4cd --- /dev/null +++ b/lib/ssh/doc/src/SSH_protocols.png diff --git a/lib/ssh/doc/src/book.xml b/lib/ssh/doc/src/book.xml index fcec1d6f70..bc104b274d 100644 --- a/lib/ssh/doc/src/book.xml +++ b/lib/ssh/doc/src/book.xml @@ -1,23 +1,24 @@ -<?xml version="1.0" encoding="latin1" ?> +<?xml version="1.0" encoding="utf-8" ?> <!DOCTYPE book SYSTEM "book.dtd"> <book xmlns:xi="http://www.w3.org/2001/XInclude"> <header titlestyle="normal"> <copyright> - <year>2005</year><year>2010</year> + <year>2005</year><year>2016</year> <holder>Ericsson AB. All Rights Reserved.</holder> </copyright> <legalnotice> - The contents of this file are subject to the Erlang Public License, - Version 1.1, (the "License"); you may not use this file except in - compliance with the License. You should have received a copy of the - Erlang Public License along with this software. If not, it can be - retrieved online at http://www.erlang.org/. + Licensed under the Apache License, Version 2.0 (the "License"); + you may not use this file except in compliance with the License. + You may obtain a copy of the License at + + http://www.apache.org/licenses/LICENSE-2.0 - Software distributed under the License is distributed on an "AS IS" - basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See - the License for the specific language governing rights and limitations - under the License. + Unless required by applicable law or agreed to in writing, software + distributed under the License is distributed on an "AS IS" BASIS, + WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + See the License for the specific language governing permissions and + limitations under the License. </legalnotice> @@ -34,6 +35,9 @@ <preamble> <contents level="2"></contents> </preamble> + <parts lift="yes"> + <xi:include href="usersguide.xml"/> + </parts> <applications> <xi:include href="ref_man.xml"/> </applications> diff --git a/lib/ssh/doc/src/fascicules.xml b/lib/ssh/doc/src/fascicules.xml index 43090b4aed..7e99398c16 100644 --- a/lib/ssh/doc/src/fascicules.xml +++ b/lib/ssh/doc/src/fascicules.xml @@ -1,7 +1,10 @@ -<?xml version="1.0" encoding="latin1" ?> +<?xml version="1.0" encoding="utf-8" ?> <!DOCTYPE fascicules SYSTEM "fascicules.dtd"> <fascicules> + <fascicule file="usersguide" href="usersguide_frame.html" entry="no"> + User's Guide + </fascicule> <fascicule file="ref_man" href="ref_man_frame.html" entry="yes"> Reference Manual </fascicule> diff --git a/lib/ssh/doc/src/introduction.xml b/lib/ssh/doc/src/introduction.xml new file mode 100644 index 0000000000..b7a73e2597 --- /dev/null +++ b/lib/ssh/doc/src/introduction.xml @@ -0,0 +1,204 @@ +<?xml version="1.0" encoding="utf-8" ?> +<!DOCTYPE chapter SYSTEM "chapter.dtd"> + +<chapter> + <header> + <copyright> + <year>2012</year> + <year>2016</year> + <holder>Ericsson AB, All Rights Reserved</holder> + </copyright> + <legalnotice> + Licensed under the Apache License, Version 2.0 (the "License"); + you may not use this file except in compliance with the License. + You may obtain a copy of the License at + + http://www.apache.org/licenses/LICENSE-2.0 + + Unless required by applicable law or agreed to in writing, software + distributed under the License is distributed on an "AS IS" BASIS, + WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + See the License for the specific language governing permissions and + limitations under the License. + + The Initial Developer of the Original Code is Ericsson AB. + </legalnotice> + + <title>Introduction</title> + <prepared>OTP team</prepared> + <responsible></responsible> + <docno></docno> + <approved></approved> + <checked></checked> + <date></date> + <rev></rev> + <file>introduction.xml</file> + </header> + <p>SSH is a protocol for secure remote logon and + other secure network services over an insecure network.</p> + <section> + <title>Scope and Purpose</title> + + <p>SSH provides a single, full-duplex, and byte-oriented connection between + client and server. The protocol also provides privacy, integrity, + server authentication, and man-in-the-middle protection.</p> + + <p>The <c>ssh</c> application is an implementation of the SSH Transport, Connection and Authentication + Layer Protocols in Erlang. It provides the following:</p> + <list type="bulleted"> + <item>API functions to write customized SSH clients and servers applications</item> + <item>The Erlang shell available over SSH</item> + <item>An SFTP client (<seealso marker="ssh_sftp">ssh_sftp</seealso>) + and server (<seealso marker="ssh_sftp">ssh_sftpd</seealso>)</item> + </list> + </section> + + <section> + <title>Prerequisites</title> + <p>It is assumed that the reader is familiar with the Erlang programming language, + concepts of <em>OTP</em>, and has a basic understanding of <em>public keys</em>.</p> + </section> + +<section> + <title>SSH Protocol Overview</title> + + <p>Conceptually, the SSH protocol can be partitioned into four + layers:</p> + + <image file="SSH_protocols.png"> + <icaption>SSH Protocol Architecture</icaption> + </image> + + <section> + <title>Transport Protocol</title> + + <p>The SSH Transport Protocol is a secure, low-level transport. + It provides strong encryption, cryptographic host + authentication, and integrity protection. A minimum of + Message Authentication Code (MAC) and encryption + algorithms are supported. For details, see the + <seealso marker="ssh">ssh(3)</seealso> manual page in <c>ssh</c>.</p> + </section> + + <section> + <title>Authentication Protocol</title> + + <p>The SSH Authentication Protocol is a general-purpose user + authentication protocol run over the SSH Transport Layer + Protocol. The <c>ssh</c> application supports user authentication as follows: + </p> + <list type="bulleted"> + <item> + Using public key technology. RSA and DSA, X509-certificates + are not supported. + </item> + <item> + Using keyboard-interactive authentication. + This is suitable for interactive authentication methods + that do not need any special software support on the client side. + Instead, all authentication data is entered from the keyboard. + </item> + <item> + Using a pure password-based authentication scheme. + Here, the plain text password is encrypted before sent + over the network. + </item> + </list> + <p>Several configuration options for + authentication handling are available in + <seealso marker="ssh#connect-3">ssh:connect/[3,4]</seealso> + and <seealso marker="ssh#daemon-2">ssh:daemon/[2,3]</seealso>.</p> + <p> + The public key handling can be customized by implementing + the following behaviours from <c>ssh</c>:</p> + <list type="bulleted"> + <item>Module + <seealso marker="ssh_client_key_api">ssh_client_key_api</seealso>. + </item> + <item>Module + <seealso marker="ssh_server_key_api">ssh_server_key_api</seealso>. + </item> + </list> + </section> + + <section> + <title>Connection Protocol</title> + + <p>The SSH Connection Protocol provides application-support + services over the transport pipe, for example, channel multiplexing, + flow control, remote program execution, signal propagation, and + connection forwarding. Functions for handling the SSH + Connection Protocol can be found in the module <seealso + marker="ssh_connection">ssh_connection</seealso> in <c>ssh</c>. + </p> + </section> + + <section> + <title>Channels</title> + + <p>All terminal sessions, forwarded connections, and so on, are + channels. Multiple channels are multiplexed into a single + connection. All channels are flow-controlled. This means that no + data is sent to a channel peer until a message is received to + indicate that window space is available. + The <em>initial window size</em> specifies how many bytes of channel + data that can be sent to the channel peer without adjusting the + window. Typically, an SSH client opens a channel, sends data (commands), + receives data (control information), and then closes the channel. + The <seealso marker="ssh_channel">ssh_channel</seealso> behaviour + handles generic parts of SSH channel management. This makes it easy + to write your own SSH client/server processes that use flow-control + and thus opens for more focus on the application logic. + </p> + + <p>Channels come in the following three flavors:</p> + + <list type="bulleted"> + <item><em>Subsystem</em> - Named services that can be run as + part of an SSH server, such as SFTP <seealso + marker="ssh_sftpd">(ssh_sftpd)</seealso>, that is built into the + SSH daemon (server) by default, but it can be disabled. The Erlang <c>ssh</c> + daemon can be configured to run any Erlang- + implemented SSH subsystem. + </item> + <item><em>Shell</em> - Interactive shell. By default the + Erlang daemon runs the Erlang shell. The shell can be customized by + providing your own read-eval-print loop. You can also provide your + own Command-Line Interface (CLI) implementation, + but that is much more work. + </item> + <item><em>Exec</em> - One-time remote execution of commands. See function + <seealso marker="ssh_connection#exec-4">ssh_connection:exec/4</seealso> + for more information.</item> + </list> + </section> + + + + </section> + + <section> + <title>Where to Find More Information</title> + <p> + For detailed information about the SSH protocol, refer to the + following Request for Comments(RFCs): + </p> + + <list type="bulleted"> + <item><url href="http://www.ietf.org/rfc/rfc4250.txt">RFC 4250</url> - + Protocol Assigned Numbers</item> + <item><url href="http://www.ietf.org/rfc/rfc4251.txt">RFC 4251</url> - + Protocol Architecture</item> + <item><url href="http://www.ietf.org/rfc/rfc4252.txt">RFC 4252</url> - + Authentication Protocol</item> + <item><url href="http://www.ietf.org/rfc/rfc4253.txt">RFC 4253</url> - + Transport Layer Protocol</item> + <item><url href="http://www.ietf.org/rfc/rfc4254.txt">RFC 4254</url> - + Connection Protocol</item> + <item><url href="http://www.ietf.org/rfc/rfc4344.txt">RFC 4344</url> - + Transport Layer Encryption Modes</item> + <item><url href="http://www.ietf.org/rfc/rfc4716.txt">RFC 4716</url> - + Public Key File Format</item> + </list> + </section> +</chapter> diff --git a/lib/ssh/doc/src/notes.xml b/lib/ssh/doc/src/notes.xml index 6e7d76c137..1837350284 100644 --- a/lib/ssh/doc/src/notes.xml +++ b/lib/ssh/doc/src/notes.xml @@ -1,23 +1,24 @@ -<?xml version="1.0" encoding="latin1" ?> +<?xml version="1.0" encoding="utf-8" ?> <!DOCTYPE chapter SYSTEM "chapter.dtd"> <chapter> <header> <copyright> - <year>2004</year><year>2012</year> + <year>2004</year><year>2016</year> <holder>Ericsson AB. All Rights Reserved.</holder> </copyright> <legalnotice> - The contents of this file are subject to the Erlang Public License, - Version 1.1, (the "License"); you may not use this file except in - compliance with the License. You should have received a copy of the - Erlang Public License along with this software. If not, it can be - retrieved online at http://www.erlang.org/. - - Software distributed under the License is distributed on an "AS IS" - basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See - the License for the specific language governing rights and limitations - under the License. + Licensed under the Apache License, Version 2.0 (the "License"); + you may not use this file except in compliance with the License. + You may obtain a copy of the License at + + http://www.apache.org/licenses/LICENSE-2.0 + + Unless required by applicable law or agreed to in writing, software + distributed under the License is distributed on an "AS IS" BASIS, + WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + See the License for the specific language governing permissions and + limitations under the License. </legalnotice> @@ -29,12 +30,1813 @@ <file>notes.xml</file> </header> -<section><title>Ssh 2.1.2.1</title> +<section><title>Ssh 4.4</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p> + A file read with an sftp client could loose data if the + packet_size is set to larger than 64k. This is corrected + now in such a way that the packet_size is silently + lowered if there is a risk for data loss.</p> + <p> + Own Id: OTP-13857 Aux Id: ERL-238, OTP-13858 </p> + </item> + <item> + <p> + When user defined SSH shell REPL process exits with + reason normal, the SSH channel callback module should + report successful exit status to the SSH client. This + provides simple way for SSH clients to check for + successful completion of executed commands. (Thanks to + isvilen)</p> + <p> + Own Id: OTP-13905 Aux Id: PR-1173 </p> + </item> + </list> + </section> + + + <section><title>Improvements and New Features</title> + <list> + <item> + <p> + Extended the option <c>silently_accept_hosts</c> for + <c>ssh:connect</c> to make it possible for the client to + check the SSH host key fingerprint string. Se the + reference manual for SSH.</p> + <p> + Own Id: OTP-13887 Aux Id: OTP-13888 </p> + </item> + </list> + </section> + +</section> + +<section><title>Ssh 4.3.6</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p> + Re-negotiation problems with OpenSSH client solved.</p> + <p> + Own Id: OTP-13972</p> + </item> + </list> + </section> + +</section> + +<section><title>Ssh 4.3.5</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p> + If a client illegaly sends an info-line and then + immediatly closes the TCP-connection, a badmatch + exception was raised.</p> + <p> + Own Id: OTP-13966</p> + </item> + </list> + </section> + +</section> + +<section><title>Ssh 4.3.4</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p> + Intermittent ssh ERROR REPORT mentioning + nonblocking_sender</p> + <p> + Own Id: OTP-13953 Aux Id: seq13199 </p> + </item> + </list> + </section> + +</section> + +<section><title>Ssh 4.3.3</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p> + Handle all possible exit values that should be + interpreted as {error, closed}. Failing to do so could + lead to unexpected crashes for users of the ssh + application.</p> + <p> + Own Id: OTP-13932 Aux Id: seq13189 </p> + </item> + </list> + </section> + +</section> + +<section><title>Ssh 4.3.2</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p> + Upgrade of an established client connection could crash + because the ssh client supervisors children had wrong + type. This is fixed now.</p> + <p> + Own Id: OTP-13782 Aux Id: seq13158 </p> + </item> + <item> + <p> + Partly checks the public key early in public key + authorization</p> + <p> + Own Id: OTP-13847 Aux Id: + defensics-ssh3.1.0-190243,205277,219318 </p> + </item> + <item> + <p> + Corrected handling of SHA for ECDSA (Elliptic curve + public keys)</p> + <p> + Own Id: OTP-13850 Aux Id: defensics-ssh3.1.0-214168 </p> + </item> + <item> + <p> + Problems found by test suites as well as by + Codenomicon/Defensics fixed: - reduce max random padding + to 15 bytes (Codenomicon/Defensics) - inclomplete pdu + handling (Codenomicon/Defensics) - badmatch in test suite + - non-blocking send fixes deadlock in + ssh_connection_SUITE:interrupted_send</p> + <p> + Own Id: OTP-13854</p> + </item> + <item> + <p> + Caller is now notified when a tcp close is received.</p> + <p> + Own Id: OTP-13859 Aux Id: seq13177 </p> + </item> + </list> + </section> + + + <section><title>Improvements and New Features</title> + <list> + <item> + <p> + Use application:ensure_all_started/2 instead of + hard-coding deps</p> + <p> + Own Id: OTP-13843 Aux Id: PR-1147 </p> + </item> + </list> + </section> + +</section> + +<section><title>Ssh 4.3.1</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p> + SSH client does not any longer retry a bad password given + as option to ssh:connect et al.</p> + <p> + Own Id: OTP-13674 Aux Id: TR-HU92273 </p> + </item> + <item> + <p> + Removed possible hanging risk for a certain timing + sequence when communicating client and server executes on + the same node.</p> + <p> + Own Id: OTP-13715</p> + </item> + </list> + </section> + +</section> + +<section><title>Ssh 4.3</title> + + <section><title>Improvements and New Features</title> + <list> + <item> + <p> + A socket created and connected by gen_tcp could now be + used as input to ssh:connect, ssh:shell, + ssh_sftp:start_channel and ssh:daemon.</p> + <p> + Own Id: OTP-12860</p> + </item> + <item> + <p> + Some time optimization mainly in message encoding.</p> + <p> + Own Id: OTP-13131</p> + </item> + <item> + <p> + Optimized the sftp client time by setting new packet and + window sizes.</p> + <p> + Own Id: OTP-13175</p> + </item> + <item> + <p> + The <c>ssh_connection_handler</c> module in SSH is + changed and now uses the new behaviour <c>gen_statem</c>. </p> + <p> + The module can be used as an example of a + <c>gen_statem</c> callback module but with a warning: + This commit of ssh is just a straightforward port from + gen_fsm to gen_statem with some code cleaning. Since the + state machine and the state callbacks are almost + unchanged the ssh module does not demonstrate the full + potential of the new behaviour.</p> + <p> + The "new" state machine uses compound states. The ssh + server and client state machines are quite similar but + differences exist. With <c>gen_fsm</c> there were flags + in the user data which in fact implemented "substates". + Now with <c>gen_statem</c> those are made explicit in the + state names, eg. the state <c>userauth</c> and the binary + <c>role</c>-flag becomes the two state names + <c>{userauth, server}</c> and <c>{userauth, client}</c>.</p> + <p> + Own Id: OTP-13267</p> + </item> + <item> + <p> + The <c>{error, Reason}</c> tuples returned from + <c>ssh_sftp</c> api functions are described.</p> + <p> + Own Id: OTP-13347 Aux Id: ERL-86 </p> + </item> + <item> + <p> + Added -spec in ssh</p> + <p> + Own Id: OTP-13479</p> + </item> + <item> + <p> + It is now possible to call <c>ssh:daemon/{1,2,3}</c> with + <c>Port=0</c>. This makes the daemon select a free + listening tcp port before opening it. To find this port + number after the call, use the new function + <c>ssh:daemon_info/1</c>. See the reference manual for + details.</p> + <p> + Own Id: OTP-13527</p> + </item> + </list> + </section> + +</section> + +<section><title>Ssh 4.2.2.1</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p> + SSH client does not any longer retry a bad password given + as option to ssh:connect et al.</p> + <p> + Own Id: OTP-13674 Aux Id: TR-HU92273 </p> + </item> + </list> + </section> + +</section> + +<section><title>Ssh 4.2.2</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p> + Documentation correction of <c>ssh_sftp:position/4</c></p> + <p> + Thanks to Rabbe Fogelholm.</p> + <p> + Own Id: OTP-13305 Aux Id: ERL-87 </p> + </item> + </list> + </section> + +</section> + +<section><title>Ssh 4.2.1</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p> + The authentication method 'keyboard-interactive' failed + in the Erlang client when the server after successful + authentication continued by asking for zero more + passwords.</p> + <p> + Own Id: OTP-13225</p> + </item> + </list> + </section> + +</section> + +<section><title>Ssh 4.2</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p> + Better error handling in ssh_file. There was some rare + errors when a NFS-mounted file was opened by ssh_file and + then remotely deleted during reading. That caused an + endless loop. </p> + <p> + That bug is now fixed.</p> + <p> + Own Id: OTP-12699 Aux Id: OTP-11688 </p> + </item> + <item> + <p> + Fixed a bug in the compression algorithm + [email protected].</p> + <p> + Own Id: OTP-12759</p> + </item> + <item> + <p> + It is now possible to start more than one daemon with a + file descriptor given in option fd. Each daemon must of + course have a unique file descriptor.</p> + <p> + Own Id: OTP-12966 Aux Id: seq12945 </p> + </item> + <item> + <p> + Fixed a bug that caused the option <c>dh_gex_limit</c> to + be ignored.</p> + <p> + Own Id: OTP-13029</p> + </item> + <item> + <p> + A problem is fixed with the <c>ssh:connect</c> option + <c>pref_public_key_algs</c> specifying user keys.</p> + <p> + Own Id: OTP-13158</p> + </item> + </list> + </section> + + + <section><title>Improvements and New Features</title> + <list> + <item> + <p> + Document updates in the ssh reference manual: app doc + file and ssh_connection.</p> + <p> + Own Id: OTP-12003</p> + </item> + <item> + <p> + The authorization phase is made stateful to prevent ssh + acting on messages sent in wrong order.</p> + <p> + Own Id: OTP-12787</p> + </item> + <item> + <p> + Testcases for bad message lengths and for bad subfield + lengths added.</p> + <p> + Own Id: OTP-12792 Aux Id: Codenomicon #5214, 6166 </p> + </item> + <item> + <p> + The 'ecdsa-sha2-nistp256', 'ecdsa-sha2-nistp384' and + 'ecdsa-sha2-nistp521' signature algorithms for ssh are + implemented. See RFC 5656.</p> + <p> + Own Id: OTP-12936</p> + </item> + <item> + <p> + The crypto algorithms 'aes192-ctr' and 'aes256-ctr' are + implemented. See RFC 4344.</p> + <p> + Own Id: OTP-12939</p> + </item> + <item> + <p> + The ciphers and macs AEAD_AES_128_GCM and + AEAD_AES_256_GCM are implemented but not enabled per + default. See the SSH App Reference Manual and RFC5647 for + details.</p> + <p> + The ciphers [email protected] and + [email protected] are also implemented and available + in the default configuration.</p> + <p> + Own Id: OTP-13018</p> + </item> + <item> + <p> + The ssh:daemon option dh_gex_groups is extended to read a + user provided ssh moduli file with generator-modulus + pairs. The file is in openssh format.</p> + <p> + Own Id: OTP-13052 Aux Id: OTP-13054 </p> + </item> + <item> + <p> + There is now a file (public_key/priv/moduli) which lists + size-generator-modulus triples. The purpose is to give + servers the possibility to select the crypto primes + randomly among a list of pregenerated triples. This + reduces the risk for some attacks on diffie-hellman + negotiation.</p> + <p> + See the reference manual for public_key:dh_gex_group/4 + where the handling of this is described.</p> + <p> + The ssh server (ssh:daemon) uses this.</p> + <p> + Own Id: OTP-13054 Aux Id: OTP-13052 </p> + </item> + <item> + <p> + The ssh:daemon option pwdfun now also takes a fun/4. This + enables the user to 1) check userid-password in another + way than the builtin algorithm, 2) implement rate + limiting per user or source IP or IP+Port, and 3) + implement blocking of missbehaving peers.</p> + <p> + The old fun/2 still works as previously.</p> + <p> + Own Id: OTP-13055 Aux Id: OTP-13053 </p> + </item> + <item> + <p> + There is now a new option to make the server limit the + size range of moduli available for the diffie-hellman + group exchange negotiation. See option <c> + {dh_gex_limits,{Min,Max}}</c> in ssh:daemon/3.</p> + <p> + Own Id: OTP-13066</p> + </item> + <item> + <p> + Ecdh key exchange now validates compressed and + uncompressed keys as defined in rfc5656</p> + <p> + Own Id: OTP-13067</p> + </item> + <item> + <p> + Search order for the .ssh directory are changed so + <c>$HOME</c> is tried before + <c>init:get_argument(home)</c>.</p> + <p> + Own Id: OTP-13109</p> + </item> + <item> + <p> + The sftp receive window handling is optimized so it will + not update the remote end too often. This makes "sftp + mget" considerable faster.</p> + <p> + Own Id: OTP-13130</p> + </item> + <item> + <p> + The option <c>key_cb</c> is extended to take an optional + list that is passed to the callback module as an option. + With this it is possible to have different keys depending + on which host that is connected. Another possibility is + to write a callback module that fetches keys etc from a + database.</p> + <p> + Thanks to Vipin Nair.</p> + <p> + Own Id: OTP-13156</p> + </item> + </list> + </section> + +</section> + +<section><title>Ssh 4.1.3</title> + + <section><title>Known Bugs and Problems</title> + <list> + <item> + <p> + SSH_MSG_KEX_DH_GEX_REQUEST_OLD implemented to make PuTTY + work with erl server.</p> + <p> + Own Id: OTP-13140</p> + </item> + </list> + </section> + +</section> + +<section><title>Ssh 4.1.2</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p> + Add a 1024 group to the list of key group-exchange groups</p> + <p> + Own Id: OTP-13046</p> + </item> + </list> + </section> + +</section> + +<section><title>Ssh 4.1.1</title> + + <section><title>Improvements and New Features</title> + <list> + <item> + <p> + A new option <c>max_channels</c> limits the number of + channels with active server-side subsystems that are + accepted.</p> + <p> + Own Id: OTP-13036</p> + </item> + </list> + </section> + +</section> + +<section><title>Ssh 4.1</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p> + Send an understandable disconnect message when the key + exchange phase can't find a common algorithm. There are + also some test cases added.</p> + <p> + Own Id: OTP-11531</p> + </item> + <item> + <p> + The third parameter in <c>ssh_sftp:write_file</c> is now + accepting iolists again. Unicode handling adjusted.</p> + <p> + Own Id: OTP-12853 Aux Id: seq12891 </p> + </item> + </list> + </section> + + + <section><title>Improvements and New Features</title> + <list> + <item> + <p> + First part of ssh test suite re-organization and + extension.</p> + <p> + Own Id: OTP-12230</p> + </item> + <item> + <p> + The key exchange algorithms 'ecdh-sha2-nistp256', + 'ecdh-sha2-nistp384' and 'ecdh-sha2-nistp521' are + implemented. See RFC 5656.</p> + <p> + This raises the security level considerably.</p> + <p> + Own Id: OTP-12622 Aux Id: OTP-12671, OTP-12672 </p> + </item> + <item> + <p> + The key exchange algorithm 'diffie-hellman-group14-sha1' + is implemented. See RFC 4253.</p> + <p> + This raises the security level.</p> + <p> + Own Id: OTP-12671 Aux Id: OTP-12672, OTP-12622 </p> + </item> + <item> + <p> + The key exchange algorithms + 'diffie-hellman-group-exchange-sha1' and + 'diffie-hellman-group-exchange-sha256' are implemented. + See RFC 4419.</p> + <p> + This raises the security level.</p> + <p> + Own Id: OTP-12672 Aux Id: OTP-12671, OTP-12622 </p> + </item> + <item> + <p> + Adding random length extra padding as recommended in RFC + 4253 section 6.</p> + <p> + Own Id: OTP-12831</p> + </item> + <item> + <p> + New test library for low-level protocol testing. There is + also a test suite using it for some preliminary tests. + The intention is to build on that for more testing of + individual ssh messages. See + <c>lib/ssh/test/ssh_trpt_test_lib.erl</c> and + <c>ssh_protocol_SUITE.erl</c> in the same directory.</p> + <p> + Own Id: OTP-12858</p> + </item> + <item> + <p> + Increased default values for + diffie-hellman-group-exchange-sha* to Min = 1024, N = + 6144, Max = 8192.</p> + <p> + Added 6144 and 8192 bit default gex groups.</p> + <p> + Own Id: OTP-12937</p> + </item> + <item> + <p> + The mac algorithm 'hmac-sha2-512' is implemented. See RFC + 6668.</p> + <p> + Own Id: OTP-12938</p> + </item> + </list> + </section> + +</section> + +<section><title>Ssh 4.0</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p> + Ssh crashed if a message was sent on a channel with + packet_size = 0.</p> + <p> + A new option for ssh:daemon is also introduced: + <c>minimal_remote_max_packet_size</c>. This option sets + the least max packet size declaration that the daemon + will accept from a client. The default value is 0 to + maintain compatibility with OpenSSH and the rfc:s.</p> + <p> + Own Id: OTP-12645 Aux Id: seq12816 </p> + </item> + <item> + <p> + Included test of the 'e' and 'f' parameters in + diffie-hellman key exchange as specified in rfc 4253 + section 8.</p> + <p> + Own Id: OTP-12649</p> + </item> + <item> + <p> + Fixes the bug that once the <c>rekey_limit</c> bytes (by + default, 1GB) had been transmitted the connection was + rekeyed every minute, not after the next transferred + 'rekey_limit' chunk.</p> + <p> + Thanks to Simon Cornish for the report and the fix!</p> + <p> + Own Id: OTP-12692</p> + </item> + <item> + <p> + Fixes a bug that causes an SFTP connection to always fail + when {timeout, Timeout} option is used with + ssh_sftp:start_channel.</p> + <p> + Thanks to Simon Cornish</p> + <p> + Own Id: OTP-12708</p> + </item> + <item> + <p> + Fix various ssh key exchange problems.</p> + <p> + Thanks to Simon Cornish</p> + <p> + Own Id: OTP-12760 Aux Id: <url + href="https://github.com/erlang/otp/pull/715">pull req + 715</url> </p> + </item> + <item> + <p> + The options <c>system_dir</c> and <c>user_dir</c> assumes + that the value is a path to a directory which is + readable. This is now checked early, so <c>ssh:daemon</c> + and <c>ssh:connect</c> will fail with an error message + immediately.</p> + <p> + Own Id: OTP-12788</p> + </item> + <item> + <p> + A daemon now checks that a client doesn't try to + authorize with methods not in the option auth_methods.</p> + <p> + Own Id: OTP-12790</p> + </item> + <item> + <p> + Disconnectfun now should trigger on all disconnects.</p> + <p> + Own Id: OTP-12811</p> + </item> + </list> + </section> + + + <section><title>Improvements and New Features</title> + <list> + <item> + <p> + Better usage of binary matching in ssh_auth.erl and + ssh_message.erl</p> + <p> + Own Id: OTP-11697</p> + </item> + <item> + <p> + A new option 'preferred_algorithms' is available for + <c>ssh:daemon</c> and <c>ssh:connect</c>.</p> + <p> + This option defines the algorithms presented to the peer + in the algorithm negotiation phase of the ssh protocol. </p> + <p> + The default list can be obtained from the new function + <c>ssh:default_algorithms/0</c>.</p> + <p> + *** INCOMPATIBILITY with removed undocumented options + 'role' and 'compression' ***</p> + <p> + Own Id: OTP-12029</p> + </item> + <item> + <p> + The internal group to user_drv protocol has been changed + to be synchronous in order to guarantee that output sent + to a process implementing the user_drv protocol is + printed before replying. This protocol is used by the + standard_output device and the ssh application when + acting as a client. </p> + <p> + This change changes the previous unlimited buffer when + printing to standard_io and other devices that end up in + user_drv to 1KB.</p> + <p> + *** POTENTIAL INCOMPATIBILITY ***</p> + <p> + Own Id: OTP-12240</p> + </item> + <item> + <p> + If ssh_connection:subsystem/4 fails we do not want to + crash but rather terminate gracefully.</p> + <p> + Own Id: OTP-12648 Aux Id: seq12834 </p> + </item> + <item> + <p> + New option <c>id_string</c> for <c>ssh:daemon</c> and + <c>ssh:connect</c> for limiting banner grabbing attempts.</p> + <p> + The possible values are: <c>{id_string,string()}</c> and + <c>{id_string,random}</c>. The latter will make ssh + generate a random nonsence id-string for each new + connection.</p> + <p> + Own Id: OTP-12659</p> + </item> + <item> + <p> + To enable the ssh daemon to run in a virtualized + environment, where there can be more that one server that + has the same ip-address and port, we add a new option + profile.</p> + <p> + Own Id: OTP-12675</p> + </item> + <item> + <p> + Upgrade test suite added.</p> + <p> + Own Id: OTP-12676</p> + </item> + <item> + <p> + A new option for handling the SSH_MSG_DEBUG message's + printouts. A fun could be given in the options that will + be called whenever the SSH_MSG_DEBUG message arrives. + This enables the user to format the printout or just + discard it.</p> + <p> + Own Id: OTP-12738 Aux Id: seq12860 </p> + </item> + <item> + <p> + Testcase improvements and corrections:</p> + <p> + * Add testcases for the <c>disconnectfun</c> option on + both server and client sides</p> + <p> + * Timeout testcases adjusted for slow machines where they + sometimes failed</p> + <p> + Own Id: OTP-12786</p> + </item> + <item> + <p> + The option <c>disconnectfun</c> can now be used both on + the client and server side.</p> + <p> + Own Id: OTP-12789</p> + </item> + <item> + <p> + A new option unknown_msgfun/2 for ssh:connect and + ssh:daemon for handling unknown messages. With the option + it is possible to intercept before an INFO log message is + generated.</p> + <p> + One usage is to filter out messages that are not wanted + in the error logger as info reports. An example of such a + message is the 'etimedout' tcp error message that will be + received if a connection has keep_alive and the peer is + restarted.</p> + <p> + Own Id: OTP-12813 Aux Id: seq12881 </p> + </item> + </list> + </section> + +</section> + +<section><title>Ssh 3.2.4</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p> + Gracefully terminate if sockets is unexpectedly closed.</p> + <p> + Own Id: OTP-12782</p> + </item> + <item> + <p> + Made Codenomicon Defensics test suite pass:</p> <list> + <item>limit number of algorithms in kexinit + message</item> <item>check 'e' and 'f' parameters in + kexdh</item> <item>implement 'keyboard-interactive' user + authentication on server side</item> <item> return plain + text message to bad version exchange message</item> + </list> + <p> + Own Id: OTP-12784</p> + </item> + </list> + </section> + +</section> + +<section><title>Ssh 3.2.3</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p> + A new option for handling the SSH_MSG_DEBUG message's + printouts. A fun could be given in the options that will + be called whenever the SSH_MSG_DEBUG message arrives. + This enables the user to format the printout or just + discard it.</p> + <p> + Own Id: OTP-12738 Aux Id: seq12860 </p> + </item> + </list> + </section> + +</section> + +<section><title>Ssh 3.2.2</title> + + <section><title>Improvements and New Features</title> + <list> + <item> + <p> + New option <c>id_string</c> for <c>ssh:daemon</c> and + <c>ssh:connect</c> for limiting banner grabbing attempts.</p> + <p> + The possible values are: <c>{id_string,string()}</c> and + <c>{id_string,random}</c>. The latter will make ssh + generate a random nonsence id-string for each new + connection.</p> + <p> + Own Id: OTP-12659</p> + </item> + </list> + </section> + +</section> + +<section><title>Ssh 3.2.1</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p> + Ssh crashed if a message was sent on a channel with + packet_size = 0.</p> + <p> + A new option for ssh:daemon is also introduced: + <c>minimal_remote_max_packet_size</c>. This option sets + the least max packet size declaration that the daemon + will accept from a client. The default value is 0 to + maintain compatibility with OpenSSH and the rfc:s.</p> + <p> + Own Id: OTP-12645 Aux Id: seq12816 </p> + </item> + </list> + </section> + +</section> + +<section><title>Ssh 3.2</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p> + If a channel is closed by the peer while using a function + with call semantics in ssh_connection.erl return {error, + closed}. Document that the functions can return {error, + timeout | closed} and not only ssh_request_status()</p> + <p> + Own Id: OTP-12004</p> + </item> + <item> + <p> + Bug that causes ssh:connect to return + <c>{error,int()}</c> instead of <c>{error,timeout}</c> + when ssh handshake takes too long time.</p> + <p> + Own Id: OTP-12369</p> + </item> + <item> + <p> + Documentation corrections. (Thanks to Rabbe Fogelholm)</p> + <p> + Own Id: OTP-12399</p> + </item> + </list> + </section> + + + <section><title>Improvements and New Features</title> + <list> + <item> + <p> + Example of ssh_connection:exec added.</p> + <p> + Own Id: OTP-12558</p> + </item> + </list> + </section> + +</section> + +<section><title>Ssh 3.1</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p> + Make sure the clean rule for ssh, ssl, eunit and otp_mibs + actually removes generated files.</p> + <p> + Own Id: OTP-12200</p> + </item> + <item> + <p> + Improved Property Tests (Thanks to Thomas, John and + Tobias at QuviQ)</p> + <p> + Own Id: OTP-12256</p> + </item> + <item> + <p> + Correct typo of renegotiate that could cause rekeying to + fail</p> + <p> + Own Id: OTP-12277 Aux Id: seq12736 </p> + </item> + <item> + <p> + The {timeout, Timeout} option passed to + ssh_sftp:start_channel was not applied to the early + phases of the SSH protocol. This patch passes the Timeout + through to ssh:connect. In case the timeout occurs during + these phases, {error, timeout} is returned. (Thanks to + Simon Cornish)</p> + <p> + Own Id: OTP-12306</p> + </item> + </list> + </section> + + + <section><title>Improvements and New Features</title> + <list> + <item> + <p> + Added API functions ptty_alloc/3 and ptty_alloc/4, to + allocate a pseudo tty.</p> + <p> + Own Id: OTP-11542 Aux Id: seq12493, OTP-11631 </p> + </item> + <item> + <p> + Supports tar file creation on other media than file + systems mounted on the local machine.</p> + <p> + The <c>erl_tar</c> api is extended with + <c>erl_tar:init/3</c> that enables usage of user provided + media storage routines. A ssh-specific set of such + routines is hidden in the new function + <c>ssh_sftp:open_tar/3</c> to simplify creating a tar + archive on a remote ssh server.</p> + <p> + A chunked file reading option is added to + <c>erl_tar:add/3,4</c> to save memory on e.g small + embedded systems. The size of the slices read from a file + in that case can be specified.</p> + <p> + Own Id: OTP-12180 Aux Id: seq12715 </p> + </item> + <item> + <p> + Always send SSH_DISCONNECT protocol messages when peer + sends corrupt messages.</p> + <p> + Own Id: OTP-12185</p> + </item> + <item> + <p> + Hooks for funs that can change binaries sent to remote + sites from erl_tar for renote tar file creation are + added. See <c>ssh_sftp:open_tar/3,4</c> for details. The + hooks could also be used to read remote tar files that + need transformation before file extraction.</p> + <p> + Those hooks are intended for encryption and decryption of + tar files. Effort is put into memory, disk and network + resource economy.</p> + <p> + Own Id: OTP-12312 Aux Id: OTP-12180 </p> + </item> + </list> + </section> + +</section> + +<section><title>Ssh 3.0.8</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p> + Fixes of login blocking after port scanning.</p> + <p> + Own Id: OTP-12247 Aux Id: seq12726 </p> + </item> + </list> + </section> + +</section> + +<section><title>Ssh 3.0.7</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p> + Add option sftp_vsn to SFTP</p> + <p> + Own Id: OTP-12227</p> + </item> + </list> + </section> + + + <section><title>Improvements and New Features</title> + <list> + <item> + <p> + Fix option user_interaction to work as expected. When + password authentication is implemented with ssh + keyboard-interactive method and the password is already + supplied, so that we do not need to query user, then + connections should succeed even though user_interaction + option is set to false.</p> + <p> + Own Id: OTP-11329 Aux Id: seq12420, seq12335 </p> + </item> + </list> + </section> + +</section> + +<section><title>Ssh 3.0.6</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p> + Gracefully handle bad data from the client when expecting + ssh version exchange.</p> + <p> + Own Id: OTP-12157 Aux Id: seq12706 </p> + </item> + <item> + <p> + When restarting an ssh daemon, that was stopped with + ssh:stop_listner/ [1,2] new options given shall replace + old ones.</p> + <p> + Own Id: OTP-12168 Aux Id: seq12711 </p> + </item> + </list> + </section> + + + <section><title>Improvements and New Features</title> + <list> + <item> + <p> + ssh now has a format_status function to avoid printing + sensitive information in error loggs.</p> + <p> + Own Id: OTP-12030</p> + </item> + </list> + </section> + + + <section><title>Known Bugs and Problems</title> + <list> + <item> + <p> + The option <c>parallel_login</c> didn't work with the + value <c>true</c>. All logins were serial.</p> + <p> + Own Id: OTP-12194</p> + </item> + </list> + </section> + +</section> + +<section><title>Ssh 3.0.5</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p> + When starting an ssh-daemon giving the option + {parallel_login, true}, the timeout for authentication + negotiation ({negotiation_timeout, integer()}) was never + removed.</p> + <p> + This caused the session to always be terminated after the + timeout if parallel_login was set.</p> + <p> + Own Id: OTP-12057 Aux Id: seq12663 </p> + </item> + </list> + </section> + + + <section><title>Improvements and New Features</title> + <list> + <item> + <p> + Warning: this is experimental and may disappear or change + without previous warning.</p> + <p> + Experimental support for running Quickcheck and PropEr + tests from common_test suites is added to common_test. + See the reference manual for the new module + <c>ct_property_testing</c>.</p> + <p> + Experimental property tests are added under + <c>lib/{inet,ssh}/test/property_test</c>. They can be run + directly or from the commont_test suites + <c>inet/ftp_property_test_SUITE.erl</c> and + <c>ssh/test/ssh_property_test_SUITE.erl</c>.</p> + <p> + See the code in the <c>test</c> directories and the man + page for details.</p> + <p> + (Thanks to Tuncer Ayaz for a patch adding Triq)</p> + <p> + Own Id: OTP-12119</p> + </item> + </list> + </section> + +</section> + +<section><title>Ssh 3.0.4</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p> + When starting an ssh-daemon giving the option + {parallel_login, true}, the timeout for authentication + negotiation ({negotiation_timeout, integer()}) was never + removed.</p> + <p> + This caused the session to always be terminated after the + timeout if parallel_login was set.</p> + <p> + Own Id: OTP-12057 Aux Id: seq12663 </p> + </item> + </list> + </section> + +</section> + +<section><title>Ssh 3.0.3</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p> + Removed mail address from error reports and corrected + spelling error (Stacktace -> stacktrace)</p> + <p> + Own Id: OTP-11883 Aux Id: seq12586 </p> + </item> + <item> + <p> + Decode/encode fixes in SSH_MSG_IGNORE and + SSH_MSG_UNIMPLEMENTED.</p> + <p> + Own Id: OTP-11983</p> + </item> + </list> + </section> + + + <section><title>Improvements and New Features</title> + <list> + <item> + <p> + Accepts that some older OpenSSH clients sends incorrect + disconnect messages.</p> + <p> + Own Id: OTP-11972</p> + </item> + <item> + <p> + Handle inet and inet6 option correctly</p> + <p> + Own Id: OTP-11976</p> + </item> + </list> + </section> + +</section> + +<section><title>Ssh 3.0.2</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p> + Fixed timeout bug in ssh:connect.</p> + <p> + Own Id: OTP-11908</p> + </item> + </list> + </section> + + + <section><title>Improvements and New Features</title> + <list> + <item> + <p> + Option <c>max_sessions</c> added to + <c>ssh:daemon/{2,3}</c>. This option, if set, limits the + number of simultaneous connections accepted by the + daemon.</p> + <p> + Own Id: OTP-11885</p> + </item> + </list> + </section> + +</section> + +<section><title>Ssh 3.0.1</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p> + Fixes the problem that ssh_cli in some cases could delay + the prompt if a tty was not requested by the client.</p> + <p> + Own Id: OTP-10732</p> + </item> + <item> + <p> + The variable NewCol is now correctly calculated allowing + for tab-completion of function calls even when preceded + with blank space (Thanks to Alexander Demidenko)</p> + <p> + Own Id: OTP-11566</p> + </item> + <item> + <p> + Fix incorrect dialyzer spec and types, also enhance + documentation. </p> + <p> + Thanks to Ayaz Tuncer.</p> + <p> + Own Id: OTP-11627</p> + </item> + <item> + <p> + Fixed a bug when ssh:exec executes a linux command on a + linux ssh daemon. If the result is sent back from + standard error, the length information was not stripped + off correctly.</p> + <p> + Own Id: OTP-11667</p> + </item> + <item> + <p> + Fixed a bug with the ssh file 'known_hosts' which made + the file grow with many equal entries.</p> + <p> + Own Id: OTP-11671</p> + </item> + <item> + <p> + Some local implementations of removing the last element + from a list are replaced by <c>lists:droplast/1</c>. Note + that this requires at least <c>stdlib-2.0</c>, which is + the stdlib version delivered in OTP 17.0. (Thanks to Hans + Svensson)</p> + <p> + Own Id: OTP-11678</p> + </item> + <item> + <p> + Bug fix for <c>ssh:daemon/2,3</c> so that the failfun is + called when it should.</p> + <p> + Own Id: OTP-11680</p> + </item> + <item> + <p> + Fixed bug which crashed ssh when SSH_MSG_KEX_DH_GEX_GROUP + is received. This could cause a vm-crash for eheap_alloc + during garbage collect.</p> + <p> + Own Id: OTP-11696 Aux Id: 12547, 12532 </p> + </item> + <item> + <p> + Fixes a bug that breaks keyboard-interactive + authentication. Thanks to Simon Cornish for reporting and + suggesting a fix.</p> + <p> + Own Id: OTP-11698</p> + </item> + <item> + <p> + dialyzer specs are now correct for <c>ssh:start/0</c>, + <c>ssh:start/1</c>, <c>ssh:stop/0</c> and + <c>ssh_connection_handler:open_channel/5</c>. (Thanks to + Johannes Weißl )</p> + <p> + Own Id: OTP-11705</p> + </item> + <item> + <p> + Application upgrade (appup) files are corrected for the + following applications: </p> + <p> + <c>asn1, common_test, compiler, crypto, debugger, + dialyzer, edoc, eldap, erl_docgen, et, eunit, gs, hipe, + inets, observer, odbc, os_mon, otp_mibs, parsetools, + percept, public_key, reltool, runtime_tools, ssh, + syntax_tools, test_server, tools, typer, webtool, wx, + xmerl</c></p> + <p> + A new test utility for testing appup files is added to + test_server. This is now used by most applications in + OTP.</p> + <p> + (Thanks to Tobias Schlager)</p> + <p> + Own Id: OTP-11744</p> + </item> + <item> + <p> + Fixed dialyzer warning for <c>ssh_connection:send</c>.</p> + <p> + Own Id: OTP-11821</p> + </item> + <item> + <p> + <c>ssh:daemon/2,3</c> : Added options + <c>negotiation_timeout</c> and <c>parallel_login</c> to + tune the authentication behaviour.</p> + <p> + Own Id: OTP-11823</p> + </item> + </list> + </section> + + + <section><title>Improvements and New Features</title> + <list> + <item> + <p> + Ssh now fully supports unicode filenames, filecontents, + shell and cli. Please note that the underlying os and + emulator must also give support for unicode. You may want + to start the emulator with "<c>erl +fnu</c>" on Linux.</p> + <p> + Own Id: OTP-10953</p> + </item> + </list> + </section> + +</section> + +<section><title>Ssh 3.0</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p> + The ssh cli is now faster at close and before new prompt.</p> + <p> + Own Id: OTP-11339 Aux Id: seq12423 </p> + </item> + <item> + <p> + Ssh process structure was redesigned to better map to + what is truly parallel this has solved a lot of strange + timing issues that sometimes would occur, for instance a + process leak could happen when a lot of connections where + taken up and down in parallel in a short period of time. + Also backwards compatible clauses to "original" but never + supported features has been removed.</p> + <p> + Impact: Increases flow efficiency</p> + <p> + *** POTENTIAL INCOMPATIBILITY ***</p> + <p> + Own Id: OTP-11363</p> + </item> + <item> + <p> + Fix various typos in erts, kernel and ssh. Thanks to + Martin Hässler.</p> + <p> + Own Id: OTP-11414</p> + </item> + <item> + <p> + Correct private_key type documentation in + ssh_server_key_api. Thanks to Tristan Sloughter.</p> + <p> + Own Id: OTP-11449</p> + </item> + <item> + <p> + The functions in ssh_no_io.erl did not mimic the + functions in ssh_io.erl correctly, the arity was + incorrect for some functions which caused ssh to fail in + the wrong way.</p> + <p> + Own Id: OTP-11490</p> + </item> + </list> + </section> + + + <section><title>Improvements and New Features</title> + <list> + <item> + <p> + Add option to disallow CLI</p> + <p> + Own Id: OTP-10976</p> + </item> + <item> + <p> + Add sockname and user to ssh:connection_info/2</p> + <p> + Own Id: OTP-11296</p> + </item> + </list> + </section> + +</section> + +<section><title>Ssh 2.1.8</title> + + <section><title>Improvements and New Features</title> + <list> + <item> + <p> + Do not chmod ~/.ssh unnecessarily.</p> + <p> + Own Id: OTP-11189</p> + </item> + <item> + <p> + Make ssh_cli.erl handle CTRL+C. Thanks to Stefan + Zegenhagen.</p> + <p> + Own Id: OTP-11199</p> + </item> + <item> + <p> + Clarified timeout options in documentation.</p> + <p> + Own Id: OTP-11249</p> + </item> + <item> + <p> + Add openssh_zlib compression type to ssh_transport. + Thanks to Louis-Philippe Gauthier.</p> + <p> + Own Id: OTP-11256</p> + </item> + </list> + </section> + +</section> + +<section><title>Ssh 2.1.7</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p> + ssh:daemon will get feeded with an argument even if it is + not a valid expression.</p> + <p> + Own Id: OTP-10975</p> + </item> + </list> + </section> + + + <section><title>Improvements and New Features</title> + <list> + <item> + <p> + Properly ignore everything in lib/ssh/doc/html/. Thanks + to Anthony Ramine.</p> + <p> + Own Id: OTP-10983</p> + </item> + <item> + <p> + Integrate elliptic curve contribution from Andreas + Schultz </p> + <p> + In order to be able to support elliptic curve cipher + suites in SSL/TLS, additions to handle elliptic curve + infrastructure has been added to public_key and crypto.</p> + <p> + This also has resulted in a rewrite of the crypto API to + gain consistency and remove unnecessary overhead. All OTP + applications using crypto has been updated to use the new + API.</p> + <p> + Impact: Elliptic curve cryptography (ECC) offers + equivalent security with smaller key sizes than other + public key algorithms. Smaller key sizes result in + savings for power, memory, bandwidth, and computational + cost that make ECC especially attractive for constrained + environments.</p> + <p> + Own Id: OTP-11009</p> + </item> + </list> + </section> + +</section> + +<section><title>Ssh 2.1.6</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p> + Fixed timing rekeying bug.</p> + <p> + Own Id: OTP-10940</p> + </item> + </list> + </section> + +</section> + +<section><title>Ssh 2.1.5</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p> + Bug in rekeying for daemon fixed.</p> + <p> + Own Id: OTP-10911</p> + </item> + </list> + </section> + + + <section><title>Improvements and New Features</title> + <list> + <item> + <p> + Enhanced error message and added test for ssh clients + trying to start non existing subsystems.</p> + <p> + Own Id: OTP-10714</p> + </item> + </list> + </section> + +</section> + +<section><title>Ssh 2.1.4</title> + + <section><title>Improvements and New Features</title> + <list> + <item> + <p> + Better quality on the error messages for when key + exchange failed.</p> + <p> + Own Id: OTP-10553 Aux Id: seq12152 </p> + </item> + <item> + <p> + Fix link to documentation for ssh:connect/3,4. Thanks to + Martin Hässler.</p> + <p> + Own Id: OTP-10862</p> + </item> + </list> + </section> + +</section> + +<section><title>Ssh 2.1.3</title> + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p> + It is now possible to send an empty binary using + ssh_connection:send/3, this corner case previously caused + ssh_connection:send to hang.</p> + <p> + Own Id: OTP-9478 Aux Id: kunagi-226 [137] </p> + </item> + <item> + <p> + Fix typo in keyboard-interactive string. Thanks to Daniel + Goertzen</p> + <p> + Own Id: OTP-10456</p> + </item> + <item> + <p> + ssh_connectino:send/3 will not return until all data has + been sent. Previously it could return too early, + resulting in things such premature close of the + connection. Also improved error handling of closed SSH + channels.</p> + <p> + Own Id: OTP-10467</p> + </item> + <item> + <p>Fixed ssh_cli.erl crashes because #state.buf is yet + 'undefined'.</p> <p>Fixed Client terminateing connections + due to channel_request message response is sent to the + wrong id.</p> <p>Affected SSH clients: - all clients + based on SSH-2.0-TrileadSSH2Java_213 (problem #1) - SSH + Term Pro (problem #2)</p> <p>Thanks to Stefan Zegenhagen + </p> + <p> + Own Id: OTP-10475</p> + </item> + <item> + <p> + Fixed various syntax errors in SSH appup file</p> + <p> + Own Id: OTP-10657</p> + </item> + </list> + </section> <section><title>Improvements and New Features</title> <list> <item> <p> + SSH_FX_FILE_IS_A_DIRECTORY message for sftp implemented</p> + <p> + Own Id: OTP-6406 Aux Id: kunagi-218 [129] </p> + </item> + <item> + <p> + SSH Rekeying fixed</p> + <p> + Own Id: OTP-7785 Aux Id: kunagi-220 [131] </p> + </item> + <item> + <p> + Added User Guide for the SSH application</p> + <p> + Own Id: OTP-7786 Aux Id: kunagi-221 [132] </p> + </item> + <item> + <p> + Documentation regarding failfun, connectfun and + disconnectfun provided</p> + <p> + Own Id: OTP-7792 Aux Id: kunagi-222 [133] </p> + </item> + <item> + <p> + SSH connection timer implementation</p> + <p> + New option, {idle_time, integer()}, sets a timeout on + connection when no channels are active, defaults to + infinity</p> + <p> + Own Id: OTP-10514 Aux Id: seq12020 </p> + </item> + <item> + <p> Some examples overflowing the width of PDF pages have + been corrected. </p> + <p> + Own Id: OTP-10665</p> + </item> + <item> + <p> + Fixed internal error on when client and server can not + agree o which authmethod to use.</p> + <p> + Own Id: OTP-10731 Aux Id: seq12237 </p> + </item> + </list> + </section> + +</section> +<section><title>Ssh 2.1.2.1</title> +<section><title>Improvements and New Features</title> + <list> + <item> + <p> Removed error report in ssh_connection_handler triggered by badmatch failure.</p> <p> @@ -44,7 +1846,6 @@ </section> </section> - <section><title>Ssh 2.1.2</title> <section><title>Fixed Bugs and Malfunctions</title> @@ -796,7 +2597,7 @@ <list> <item> <p> - Ssh timeouts will now behave as expected e.i. defaults to + Ssh timeouts will now behave as expected i.e. defaults to infinity only the user of the ssh application can know of a reasonable timeout value for their application.</p> <p> @@ -849,7 +2650,7 @@ caused the ssh daemon to close the connections to all currently logged in users if one user logged out. Another problem related to the supervision tree caused the closing - down of clients to leak processes e.i. all processes was + down of clients to leak processes i.e. all processes was not shutdown correctly.</p> <p> Own Id: OTP-7676</p> @@ -941,7 +2742,7 @@ slightly changes the options to the API function ssh:daemon/[1,2,3] deprecating all no longer documented options. Note that the new API enforces the "logical way" - of using the old API e.i. making the subsystem process + of using the old API i.e. making the subsystem process part of the ssh applications supervisor tree, so missuses of the old API are not compatible with the new API.</p> <p> diff --git a/lib/ssh/doc/src/part_notes.xml b/lib/ssh/doc/src/part_notes.xml index 1b47a12021..aaca8ca9f2 100644 --- a/lib/ssh/doc/src/part_notes.xml +++ b/lib/ssh/doc/src/part_notes.xml @@ -1,23 +1,24 @@ -<?xml version="1.0" encoding="latin1" ?> +<?xml version="1.0" encoding="utf-8" ?> <!DOCTYPE part SYSTEM "part.dtd"> <part xmlns:xi="http://www.w3.org/2001/XInclude"> <header> <copyright> - <year>2004</year><year>2010</year> + <year>2004</year><year>2016</year> <holder>Ericsson AB. All Rights Reserved.</holder> </copyright> <legalnotice> - The contents of this file are subject to the Erlang Public License, - Version 1.1, (the "License"); you may not use this file except in - compliance with the License. You should have received a copy of the - Erlang Public License along with this software. If not, it can be - retrieved online at http://www.erlang.org/. + Licensed under the Apache License, Version 2.0 (the "License"); + you may not use this file except in compliance with the License. + You may obtain a copy of the License at + + http://www.apache.org/licenses/LICENSE-2.0 - Software distributed under the License is distributed on an "AS IS" - basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See - the License for the specific language governing rights and limitations - under the License. + Unless required by applicable law or agreed to in writing, software + distributed under the License is distributed on an "AS IS" BASIS, + WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + See the License for the specific language governing permissions and + limitations under the License. </legalnotice> diff --git a/lib/ssh/doc/src/ref_man.xml b/lib/ssh/doc/src/ref_man.xml index 9ab56b28ec..140ebd8c76 100644 --- a/lib/ssh/doc/src/ref_man.xml +++ b/lib/ssh/doc/src/ref_man.xml @@ -1,40 +1,44 @@ -<?xml version="1.0" encoding="latin1" ?> +<?xml version="1.0" encoding="utf-8" ?> <!DOCTYPE application SYSTEM "application.dtd"> <application xmlns:xi="http://www.w3.org/2001/XInclude"> <header> <copyright> - <year>2004</year><year>2010</year> + <year>2004</year><year>2016</year> <holder>Ericsson AB. All Rights Reserved.</holder> </copyright> <legalnotice> - The contents of this file are subject to the Erlang Public License, - Version 1.1, (the "License"); you may not use this file except in - compliance with the License. You should have received a copy of the - Erlang Public License along with this software. If not, it can be - retrieved online at http://www.erlang.org/. + Licensed under the Apache License, Version 2.0 (the "License"); + you may not use this file except in compliance with the License. + You may obtain a copy of the License at + + http://www.apache.org/licenses/LICENSE-2.0 - Software distributed under the License is distributed on an "AS IS" - basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See - the License for the specific language governing rights and limitations - under the License. + Unless required by applicable law or agreed to in writing, software + distributed under the License is distributed on an "AS IS" BASIS, + WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + See the License for the specific language governing permissions and + limitations under the License. </legalnotice> <title>SSH Reference Manual</title> - <prepared>Jakob Cederlund</prepared> - <docno></docno> + <prepared>OTP</prepared> <date>2007-10-06</date> <rev>%VSN%</rev> - <file>application.sgml</file> + <file>ref_man.xml</file> </header> <description> - <p>The SSH application is an erlang implementation of the - secure shell protocol.</p> + <p>The <c>ssh</c> application is an Erlang implementation of the + Secure Shell Protocol (SSH) as defined by RFC 4250 - 4254.</p> + </description> + <xi:include href="ssh_app.xml"/> <xi:include href="ssh.xml"/> <xi:include href="ssh_channel.xml"/> <xi:include href="ssh_connection.xml"/> + <xi:include href="ssh_client_key_api.xml"/> + <xi:include href="ssh_server_key_api.xml"/> <xi:include href="ssh_sftp.xml"/> <xi:include href="ssh_sftpd.xml"/> </application> diff --git a/lib/ssh/doc/src/ssh.xml b/lib/ssh/doc/src/ssh.xml index 57f09c0cf0..6b49f89449 100644 --- a/lib/ssh/doc/src/ssh.xml +++ b/lib/ssh/doc/src/ssh.xml @@ -1,220 +1,369 @@ -<?xml version="1.0" encoding="iso-8859-1" ?> +<?xml version="1.0" encoding="utf-8" ?> <!DOCTYPE erlref SYSTEM "erlref.dtd"> <erlref> <header> <copyright> - <year>2004</year><year>2012</year> + <year>2004</year><year>2016</year> <holder>Ericsson AB. All Rights Reserved.</holder> </copyright> <legalnotice> - The contents of this file are subject to the Erlang Public License, - Version 1.1, (the "License"); you may not use this file except in - compliance with the License. You should have received a copy of the - Erlang Public License along with this software. If not, it can be - retrieved online at http://www.erlang.org/. + Licensed under the Apache License, Version 2.0 (the "License"); + you may not use this file except in compliance with the License. + You may obtain a copy of the License at + + http://www.apache.org/licenses/LICENSE-2.0 - Software distributed under the License is distributed on an "AS IS" - basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See - the License for the specific language governing rights and limitations - under the License. + Unless required by applicable law or agreed to in writing, software + distributed under the License is distributed on an "AS IS" BASIS, + WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + See the License for the specific language governing permissions and + limitations under the License. </legalnotice> <title>ssh</title> - <prepared>Ingela Anderton Andin</prepared> - <responsible>Håkan Mattsson</responsible> + <prepared></prepared> <docno></docno> - <approved>Håkan Mattsson</approved> - <checked></checked> <date>2007-10-06</date> - <rev>PA1</rev> + <rev></rev> </header> <module>ssh</module> - <modulesummary>Main API of the SSH application</modulesummary> + <modulesummary>Main API of the ssh application</modulesummary> <description> - <p>Interface module for the SSH application. </p> + <p>Interface module for the <c>ssh</c> application.</p> + <p>See <seealso marker="ssh:SSH_app#supported">ssh(6)</seealso> for details of supported version, + algorithms and unicode support.</p> </description> - <section> - <title>SSH</title> + <section> + <title>OPTIONS</title> + <p>The exact behaviour of some functions can be adjusted with the use of options which are documented together + with the functions. Generally could each option be used at most one time in each function call. If given two or more + times, the effect is not predictable unless explicitly documented.</p> + <p>The options are of different kinds:</p> + <taglist> + <tag>Limits</tag> + <item><p>which alters limits in the system, for example number of simultaneous login attempts.</p></item> - <list type="bulleted"> - <item>ssh requires the crypto and public_key applications.</item> - <item>Supported SSH-version is 2.0 </item> - <item>Currently supports only a minimum of mac and encryption algorithms i.e. - hmac-sha1, and aes128-cb and 3des-cbc.</item> - </list> - + <tag>Timeouts</tag> + <item><p>which give some defined behaviour if too long time elapses before a given event or action, + for example time to wait for an answer.</p></item> + + <tag>Callbacks</tag> + <item><p>which gives the caller of the function the possibility to execute own code on some events, + for example calling an own logging function or to perform an own login function</p></item> + + <tag>Behaviour</tag> + <item><p>which changes the systems behaviour.</p></item> + </taglist> </section> - + <section> - <title>COMMON DATA TYPES </title> + <title>DATA TYPES</title> <p>Type definitions that are used more than once in - this module:</p> - <p><c>boolean() = true | false </c></p> - <p><c>string() = list of ASCII characters</c></p> - <p><c>ssh_daemon_ref() - opaque to the user - returned by ssh:daemon/[1,2,3]</c></p> - <p><c>ssh_connection_ref() - opaque to the user - returned by ssh:connect/3</c></p> - <p><c>ip_address() - {N1,N2,N3,N4} % IPv4 | - {K1,K2,K3,K4,K5,K6,K7,K8} % IPv6</c></p> - <p><c>subsystem_spec() = {subsystem_name(), {channel_callback(), channel_init_args()}} </c></p> - <p><c>subsystem_name() = string() </c></p> - <p><c>channel_callback() = atom() - Name of the erlang module - implementing the subsystem using the ssh_channel behavior see</c> - <seealso marker="ssh_channel">ssh_channel(3)</seealso></p> - <p><c>channel_init_args() = list()</c></p> - </section> - + this module, or abstractions to indicate the intended use of the data + type, or both:</p> + <taglist> + <tag><c>boolean() =</c></tag> + <item><p><c>true | false</c></p></item> + <tag><c>string() =</c></tag> + <item><p><c>[byte()]</c></p></item> + <tag><c>ssh_daemon_ref() =</c></tag> + <item><p>opaque() - + as returned by <c>ssh:daemon/[1,2,3]</c></p></item> + <tag><c>ssh_connection_ref() =</c></tag> + <item><p>opaque() - as returned by <c>ssh:connect/3</c></p></item> + <tag><c>ip_address() =</c></tag> + <item><p><c>inet::ip_address</c></p></item> + <tag><c>subsystem_spec() =</c></tag> + <item><p><c>{subsystem_name(), + {channel_callback(), channel_init_args()}}</c></p></item> + <tag><c>subsystem_name() =</c></tag> + <item><p><c>string()</c></p></item> + <tag><c>channel_callback() =</c></tag> + <item><p><c>atom()</c> - Name of the Erlang module + implementing the subsystem using the <c>ssh_channel</c> behavior, see + <seealso marker="ssh_channel">ssh_channel(3)</seealso></p></item> + <tag><c>key_cb() =</c></tag> + <item> + <p><c>atom() | {atom(), list()}</c></p> + <p><c>atom()</c> - Name of the erlang module implementing the behaviours + <seealso marker="ssh_client_key_api">ssh_client_key_api</seealso> or + <seealso marker="ssh_client_key_api">ssh_client_key_api</seealso> as the + case maybe.</p> + <p><c>list()</c> - List of options that can be passed to the callback module.</p> + </item> + <tag><c>channel_init_args() =</c></tag> + <item><p><c>list()</c></p></item> + + <tag><c>algs_list() =</c></tag> + <item><p><c>list( alg_entry() )</c></p></item> + + <tag><c>alg_entry() =</c></tag> + <item><p><c>{kex, simple_algs()} | {public_key, simple_algs()} | {cipher, double_algs()} | {mac, double_algs()} | {compression, double_algs()}</c></p></item> + + <tag><c>simple_algs() =</c></tag> + <item><p><c>list( atom() )</c></p></item> + + <tag><c>double_algs() =</c></tag> + <item><p><c>[{client2serverlist,simple_algs()},{server2client,simple_algs()}] | simple_algs()</c></p></item> + </taglist> +</section> + <funcs> <func> <name>close(ConnectionRef) -> ok </name> - <fsummary>Closes a ssh connection</fsummary> + <fsummary>Closes an SSH connection.</fsummary> <type> <v>ConnectionRef = ssh_connection_ref()</v> </type> - <desc><p>Closes a ssh connection.</p> + <desc><p>Closes an SSH connection.</p> </desc> </func> <func> <name>connect(Host, Port, Options) -> </name> - <name>connect(Host, Port, Options, Timeout) -> {ok, ssh_connection_ref()} - | {error, Reason}</name> - <fsummary>Connect to an ssh server.</fsummary> + <name>connect(Host, Port, Options, Timeout) -> </name> + <name>connect(TcpSocket, Options) -> </name> + <name>connect(TcpSocket, Options, Timeout) -> + {ok, ssh_connection_ref()} | {error, Reason}</name> + <fsummary>Connects to an SSH server.</fsummary> <type> <v>Host = string()</v> <v>Port = integer()</v> - <d>The default is <c><![CDATA[22]]></c>, the registered port for SSH.</d> + <d><c><![CDATA[22]]></c> is default, the assigned well-known port + number for SSH.</d> <v>Options = [{Option, Value}]</v> - <v>Timeout = infinity | integer(milliseconds)</v> + <v>Timeout = infinity | integer()</v> + <d>Negotiation time-out in milli-seconds. The default value is <c>infinity</c>. + For connection time-out, use option <c>{connect_timeout, timeout()}</c>.</d> + <v>TcpSocket = port()</v> + <d>The socket is supposed to be from <seealso marker="kernel:gen_tcp#connect-3">gen_tcp:connect</seealso> or <seealso marker="kernel:gen_tcp#accept-1">gen_tcp:accept</seealso> with option <c>{active,false}</c></d> </type> <desc> - <p>Connects to an SSH server. No channel is started this is done - by calling ssh_connect:session_channel/2.</p> - <p>Options are:</p> + <p>Connects to an SSH server. No channel is started. This is done + by calling + <seealso marker="ssh_connection#session_channel/2"> + ssh_connection:session_channel/[2, 4]</seealso>.</p> + <p>Options:</p> <taglist> + <tag><c><![CDATA[{inet, inet | inet6}]]></c></tag> + <item> + <p>IP version to use.</p> + </item> <tag><c><![CDATA[{user_dir, string()}]]></c></tag> <item> - <p>Sets the user directory e.i. the directory containing - ssh configuration files for the user such as - <c><![CDATA[known_hosts]]></c>, <c><![CDATA[id_rsa, id_dsa]]></c> and - <c><![CDATA[authorized_key]]></c>. Defaults to the directory normally - referred to as <c><![CDATA[~/.ssh]]></c> </p> + <p>Sets the user directory, that is, the directory containing + <c>ssh</c> configuration files for the user, such as + <c><![CDATA[known_hosts]]></c>, <c><![CDATA[id_rsa, + id_dsa]]></c>, and + <c><![CDATA[authorized_key]]></c>. Defaults to the + directory normally referred to as + <c><![CDATA[~/.ssh]]></c>.</p> </item> <tag><c><![CDATA[{dsa_pass_phrase, string()}]]></c></tag> <item> - <p>If the user dsa key is protected by a pass phrase it can be + <p>If the user DSA key is protected by a passphrase, it can be supplied with this option. </p> </item> <tag><c><![CDATA[{rsa_pass_phrase, string()}]]></c></tag> <item> - <p>If the user rsa key is protected by a pass phrase it can be + <p>If the user RSA key is protected by a passphrase, it can be supplied with this option. </p> </item> - <tag><c><![CDATA[{silently_accept_hosts, boolean()}]]></c></tag> + <tag><c><![CDATA[{silently_accept_hosts, boolean() | accept_fun() | {crypto:digest_type(), accept_fun()} }]]></c> + <br/> + <c><![CDATA[accept_fun() :: fun(PeerName::string(), FingerPrint::string()) -> boolean()]]></c> + </tag> <item> - <p>When true hosts are added to the + <p>When <c>true</c>, hosts are added to the file <c><![CDATA[known_hosts]]></c> without asking the user. - Defaults to false. + Defaults to <c>false</c> which will give a user question on stdio of whether to accept or reject a previously + unseen host.</p> + <p>If the option value is has an <c>accept_fun()</c>, that fun will called with the arguments + <c>(PeerName, PeerHostKeyFingerPrint)</c>. The fingerprint is calculated on the Peer's Host Key with + <seealso marker="public_key:public_key#ssh_hostkey_fingerprint-1">public_key:ssh_hostkey_fingerprint/1</seealso>. + </p> + <p>If the <c>crypto:digest_type()</c> is present, the fingerprint is calculated with that digest type by the function + <seealso marker="public_key:public_key#ssh_hostkey_fingerprint-2">public_key:ssh_hostkey_fingerprint/2</seealso>. </p> </item> <tag><c><![CDATA[{user_interaction, boolean()}]]></c></tag> <item> - <p>If false disables the client to connect to the server - if any user interaction is needed such as accepting that - the server will be added to the <c>known_hosts</c> file or - supplying a password. Defaults to true. + <p>If <c>false</c>, disables the client to connect to the server + if any user interaction is needed, such as accepting + the server to be added to the <c>known_hosts</c> file, or + supplying a password. Defaults to <c>true</c>. Even if user interaction is allowed it can be - suppressed by other options such as silently_accept_hosts and - password. Do note that it may not always be desirable to use - those options from a security point of view.</p> + suppressed by other options, such as <c>silently_accept_hosts</c> + and <c>password</c>. However, those optins are not always desirable + to use from a security point of view.</p> </item> - <tag><c><![CDATA[{public_key_alg, ssh_rsa | ssh_dsa}]]></c></tag> + + <tag><c><![CDATA[{disconnectfun, fun(Reason:term()) -> _}]]></c></tag> <item> + <p>Provides a fun to implement your own logging when a server disconnects the client.</p> + </item> + + <tag><c><![CDATA[{unexpectedfun, fun(Message:term(), Peer) -> report | skip }]]></c></tag> + <item> + <p>Provides a fun to implement your own logging or other action when an unexpected message arrives. + If the fun returns <c>report</c> the usual info report is issued but if <c>skip</c> is returned no + report is generated.</p> + <p><c>Peer</c> is in the format of <c>{Host,Port}</c>.</p> + </item> + + <tag><c><![CDATA[{public_key_alg, 'ssh-rsa' | 'ssh-dss'}]]></c></tag> + <item> + <note> + <p>This option will be removed in OTP 20, but is kept for compatibility. It is ignored if + the preferred <c>pref_public_key_algs</c> option is used.</p> + </note> <p>Sets the preferred public key algorithm to use for user - authentication. If the the preferred algorithm fails of - some reason, the other algorithm is tried. The default is - to try <c><![CDATA[ssh_rsa]]></c> first.</p> + authentication. If the preferred algorithm fails, + the other algorithm is tried. If <c>{public_key_alg, 'ssh-rsa'}</c> is set, it is translated + to <c>{pref_public_key_algs, ['ssh-rsa','ssh-dss']}</c>. If it is + <c>{public_key_alg, 'ssh-dss'}</c>, it is translated + to <c>{pref_public_key_algs, ['ssh-dss','ssh-rsa']}</c>. + </p> </item> + <tag><c><![CDATA[{pref_public_key_algs, list()}]]></c></tag> <item> - <p>List of public key algorithms to try to use, ssh_rsa and ssh_dsa available. - Will override <c><![CDATA[{public_key_alg, ssh_rsa | ssh_dsa}]]></c></p> + <p>List of user (client) public key algorithms to try to use.</p> + <p>The default value is + <c><![CDATA[['ssh-rsa','ssh-dss','ecdsa-sha2-nistp256','ecdsa-sha2-nistp384','ecdsa-sha2-nistp521'] ]]></c> + </p> + <p>If there is no public key of a specified type available, the corresponding entry is ignored.</p> + </item> + + <tag><c><![CDATA[{preferred_algorithms, algs_list()}]]></c></tag> + <item> + <p>List of algorithms to use in the algorithm negotiation. The default <c>algs_list()</c> can + be obtained from <seealso marker="#default_algorithms/0">default_algorithms/0</seealso>. + </p> + <p>If an alg_entry() is missing in the algs_list(), the default value is used for that entry.</p> + <p>Here is an example of this option:</p> + <code> +{preferred_algorithms, + [{public_key,['ssh-rsa','ssh-dss']}, + {cipher,[{client2server,['aes128-ctr']}, + {server2client,['aes128-cbc','3des-cbc']}]}, + {mac,['hmac-sha2-256','hmac-sha1']}, + {compression,[none,zlib]} + ] +} +</code> + <p>The example specifies different algorithms in the two directions (client2server and server2client), + for cipher but specifies the same algorithms for mac and compression in both directions. + The kex (key exchange) is implicit but public_key is set explicitly.</p> + + <warning> + <p>Changing the values can make a connection less secure. Do not change unless you + know exactly what you are doing. If you do not understand the values then you + are not supposed to change them.</p> + </warning> </item> + + <tag><c><![CDATA[{dh_gex_limits,{Min=integer(),I=integer(),Max=integer()}}]]></c></tag> + <item> + <p>Sets the three diffie-hellman-group-exchange parameters that guides the connected server in choosing a group. + See RFC 4419 for the function of thoose. The default value is <c>{1024, 6144, 8192}</c>. + </p> + </item> + <tag><c><![CDATA[{connect_timeout, timeout()}]]></c></tag> <item> - <p>Sets a timeout on the transport layer connection. Defaults to infinity.</p> + <p>Sets a time-out on the transport layer + connection. For <c>gen_tcp</c> the time is in milli-seconds and the default value is + <c>infinity</c>.</p> </item> - <tag><c><![CDATA[{user, String}]]></c></tag> + <tag><c><![CDATA[{user, string()}]]></c></tag> <item> - <p>Provide a user name. If this option is not given, ssh + <p>Provides a username. If this option is not given, <c>ssh</c> reads from the environment (<c><![CDATA[LOGNAME]]></c> or - <c><![CDATA[USER]]></c> on unix, + <c><![CDATA[USER]]></c> on UNIX, <c><![CDATA[USERNAME]]></c> on Windows).</p> </item> <tag><c><![CDATA[{password, string()}]]></c></tag> <item> - <p>Provide a password for password authentication. If - this option is not given, the user will be asked for a - password if the password authentication method is + <p>Provides a password for password authentication. + If this option is not given, the user is asked for a + password, if the password authentication method is attempted.</p> </item> - <tag><c><![CDATA[{user_auth, Fun/3}]]></c></tag> - <item> - <p>Provide a fun for password authentication. The fun - will be called as <c><![CDATA[fun(User, Password, Opts)]]></c> and - should return <c><![CDATA[true]]></c> or <c><![CDATA[false]]></c>.</p> - </item> - <tag><c><![CDATA[{key_cb, atom() = KeyCallbackModule}]]></c></tag> - <item> - <p>Provide a special call-back module for key handling. - The call-back module should be modeled after the - <c><![CDATA[ssh_file]]></c> module. The functions that must - be exported are: - <c><![CDATA[private_host_rsa_key/2]]></c>, - <c><![CDATA[private_host_dsa_key/2]]></c>, - <c><![CDATA[lookup_host_key/3]]></c> and - <c><![CDATA[add_host_key/3]]></c>. This is considered - somewhat experimental and will be better documented later on.</p> + <tag><c><![CDATA[{key_cb, key_cb()}]]></c></tag> + <item> + <p>Module implementing the behaviour <seealso + marker="ssh_client_key_api">ssh_client_key_api</seealso>. Can be used to + customize the handling of public keys. If callback options are provided + along with the module name, they are made available to the callback + module via the options passed to it under the key 'key_cb_private'. + </p> </item> <tag><c><![CDATA[{quiet_mode, atom() = boolean()}]]></c></tag> <item> - <p>If true, the client will not print out anything on authorization.</p> + <p>If <c>true</c>, the client does not print anything on authorization.</p> + </item> + + <tag><c><![CDATA[{id_string, random | string()}]]></c></tag> + <item> + <p>The string that the client presents to a connected server initially. The default value is "Erlang/VSN" where VSN is the ssh application version number. + </p> + <p>The value <c>random</c> will cause a random string to be created at each connection attempt. This is to make it a bit more difficult for a malicious peer to find the ssh software brand and version. + </p> </item> + <tag><c><![CDATA[{fd, file_descriptor()}]]></c></tag> <item> - <p>Allow an existing file-descriptor to be used - (simply passed on to the transport protocol).</p></item> - <tag><c><![CDATA[{ip_v6_disabled, boolean()}]]></c></tag> + <p>Allows an existing file descriptor to be used + (by passing it on to the transport protocol).</p></item> + <tag><c><![CDATA[{rekey_limit, integer()}]]></c></tag> + <item> + <p>Provides, in bytes, when rekeying is to be initiated. + Defaults to once per each GB and once per hour.</p> + </item> + <tag><c><![CDATA[{idle_time, integer()}]]></c></tag> <item> - <p>Determines if SSH shall use IPv6 or not.</p></item> + <p>Sets a time-out on a connection when no channels are active. + Defaults to <c>infinity</c>.</p></item> + <tag><c><![CDATA[{ssh_msg_debug_fun, fun(ConnectionRef::ssh_connection_ref(), AlwaysDisplay::boolean(), Msg::binary(), LanguageTag::binary()) -> _}]]></c></tag> + <item> + <p>Provide a fun to implement your own logging of the SSH message SSH_MSG_DEBUG. The last three parameters are from the message, see RFC4253, section 11.3. The <c>ConnectionRef</c> is the reference to the connection on which the message arrived. The return value from the fun is not checked.</p> + <p>The default behaviour is ignore the message. + To get a printout for each message with <c>AlwaysDisplay = true</c>, use for example <c>{ssh_msg_debug_fun, fun(_,true,M,_)-> io:format("DEBUG: ~p~n", [M]) end}</c></p> + </item> + </taglist> </desc> </func> <func> - <name>connection_info(ConnectionRef, [Option]) ->[{Option, Value}] </name> - <fsummary> Retrieves information about a connection. </fsummary> + <name>connection_info(ConnectionRef, [Option]) ->[{Option, + Value}]</name> + <fsummary>Retrieves information about a connection.</fsummary> <type> - <v>Option = client_version | server_version | peer</v> - <v>Value = term() </v> + <v>Option = client_version | server_version | user | peer | sockname </v> + <v>Value = [option_value()] </v> + <v>option_value() = {{Major::integer(), Minor::integer()}, VersionString::string()} | + User::string() | Peer::{inet:hostname(), {inet::ip_adress(), inet::port_number()}} | + Sockname::{inet::ip_adress(), inet::port_number()}</v> </type> <desc> - <p> Retrieves information about a connection. - </p> + <p>Retrieves information about a connection.</p> </desc> </func> <func> <name>daemon(Port) -> </name> <name>daemon(Port, Options) -> </name> - <name>daemon(HostAddress, Port, Options) -> ssh_daemon_ref()</name> + <name>daemon(HostAddress, Port, Options) -> </name> + <name>daemon(TcpSocket) -> </name> + <name>daemon(TcpSocket, Options) -> {ok, ssh_daemon_ref()} | {error, atom()}</name> <fsummary>Starts a server listening for SSH connections on the given port.</fsummary> <type> @@ -223,106 +372,383 @@ <v>Options = [{Option, Value}]</v> <v>Option = atom()</v> <v>Value = term()</v> + <v>TcpSocket = port()</v> + <d>The socket is supposed to be from <seealso marker="kernel:gen_tcp#connect-3">gen_tcp:connect</seealso> or <seealso marker="kernel:gen_tcp#accept-1">gen_tcp:accept</seealso> with option <c>{active,false}</c></d> </type> <desc> - <p>Starts a server listening for SSH connections on the given port.</p> - - <p>Options are:</p> + <p>Starts a server listening for SSH connections on the given + port. If the <c>Port</c> is 0, a random free port is selected. See + <seealso marker="#daemon_info/1">daemon_info/1</seealso> about how to find the selected port number.</p> + <p>Options:</p> <taglist> - <tag><c><![CDATA[{subsystems, [subsystem_spec()]]]></c></tag> + <tag><c><![CDATA[{inet, inet | inet6}]]></c></tag> + <item><p>IP version to use when the host address is specified as <c>any</c>.</p></item> + <tag><c><![CDATA[{subsystems, [subsystem_spec()]}]]></c></tag> <item> - Provides specifications for handling of subsystems. The - "sftp" subsystem-spec can be retrieved by calling - ssh_sftpd:subsystem_spec/1. If the subsystems option in not present - the value of <c>[ssh_sftpd:subsystem_spec([])]</c> will be used. - It is of course possible to set the option to the empty list - if you do not want the daemon to run any subsystems at all. + <p>Provides specifications for handling of subsystems. The + "sftp" subsystem specification is retrieved by calling + <c>ssh_sftpd:subsystem_spec/1</c>. If the subsystems option is + not present, the value of + <c>[ssh_sftpd:subsystem_spec([])]</c> is used. + The option can be set to the empty list if + you do not want the daemon to run any subsystems.</p> </item> - <tag><c><![CDATA[{shell, {Module, Function, Args} | fun(string() = User) - > pid() | - fun(string() = User, ip_address() = PeerAddr) -> pid()}]]></c></tag> + <tag><c><![CDATA[{shell, {Module, Function, Args} | + fun(string() = User) - > pid() | fun(string() = User, + ip_address() = PeerAddr) -> pid()}]]></c></tag> <item> - Defines the read-eval-print loop used when a shell is requested - by the client. Example use the - erlang shell: <c><![CDATA[{shell, start, []}]]></c> which is - the default behavior. + <p>Defines the read-eval-print loop used when a shell is + requested by the client. The default is to use the Erlang shell: + <c><![CDATA[{shell, start, []}]]></c></p> </item> - <tag><c><![CDATA[{ssh_cli,{channel_callback(), channel_init_args()}}]]></c></tag> + <tag><c><![CDATA[{ssh_cli, {channel_callback(), + channel_init_args()} | no_cli}]]></c></tag> <item> - Provide your own cli implementation, e.i. a channel callback - module that implements a shell and command execution. Note - that you may customize the shell read-eval-print loop using the - option <c>shell</c> which is much less work than implementing - your own cli channel. + <p>Provides your own CLI implementation, that is, a channel callback + module that implements a shell and command execution. The shell + read-eval-print loop can be customized, using the + option <c>shell</c>. This means less work than implementing + an own CLI channel. If set to <c>no_cli</c>, the CLI channels + are disabled and only subsystem channels are allowed.</p> </item> - <tag><c><![CDATA[{user_dir, String}]]></c></tag> + <tag><c><![CDATA[{user_dir, string()}]]></c></tag> <item> - <p>Sets the user directory e.i. the directory containing - ssh configuration files for the user such as - <c><![CDATA[known_hosts]]></c>, <c><![CDATA[id_rsa, id_dsa]]></c> and - <c><![CDATA[authorized_key]]></c>. Defaults to the directory normally - referred to as <c><![CDATA[~/.ssh]]></c> </p> + <p>Sets the user directory. That is, the directory containing + <c>ssh</c> configuration files for the user, such as + <c><![CDATA[known_hosts]]></c>, <c><![CDATA[id_rsa, + id_dsa]]></c>, and + <c><![CDATA[authorized_key]]></c>. Defaults to the + directory normally referred to as + <c><![CDATA[~/.ssh]]></c>.</p> </item> <tag><c><![CDATA[{system_dir, string()}]]></c></tag> <item> - <p>Sets the system directory, containing the host files - that identifies the host for ssh. The default is - <c><![CDATA[/etc/ssh]]></c>, note that SSH normally - requires the host files there to be readable only by - root.</p> + <p>Sets the system directory, containing the host key files + that identify the host keys for <c>ssh</c>. Defaults to + <c><![CDATA[/etc/ssh]]></c>. For security reasons, + this directory is normally accessible only to the root user.</p> </item> + <tag><c><![CDATA[{auth_methods, string()}]]></c></tag> <item> - <p>Comma separated string that determines which authentication methodes that the server - should support and in what order they will be tried. Defaults to - <c><![CDATA["publickey,keyboard_interactive,password"]]></c></p> + <p>Comma-separated string that determines which + authentication methods that the server is to support and + in what order they are tried. Defaults to + <c><![CDATA["publickey,keyboard-interactive,password"]]></c></p> </item> - <tag><c><![CDATA[{user_passwords, [{string() = User, string() = Password}]}]]></c></tag> + + <tag><c><![CDATA[{auth_method_kb_interactive_data, PromptTexts}]]></c> + <br/><c>where:</c> + <br/><c>PromptTexts = kb_int_tuple() | fun(Peer::{IP::tuple(),Port::integer()}, User::string(), Service::string()) -> kb_int_tuple()</c> + <br/><c>kb_int_tuple() = {Name::string(), Instruction::string(), Prompt::string(), Echo::boolean()}</c> + </tag> <item> - <p>Provide passwords for password authentication.They will - be used when someone tries to connect to the server and - public key user authentication fails. The option provides - a list of valid user names and the corresponding password. + <p>Sets the text strings that the daemon sends to the client for presentation to the user when using <c>keyboar-interactive</c> authentication. If the fun/3 is used, it is called when the actual authentication occurs and may therefore return dynamic data like time, remote ip etc.</p> + <p>The parameter <c>Echo</c> guides the client about need to hide the password.</p> + <p>The default value is: + <c>{auth_method_kb_interactive_data, {"SSH server", "Enter password for \""++User++"\"", "password: ", false}></c></p> + </item> + + <tag><c><![CDATA[{user_passwords, [{string() = User, + string() = Password}]}]]></c></tag> + <item> + <p>Provides passwords for password authentication. The passwords + are used when someone tries to connect to the server and + public key user-authentication fails. The option provides + a list of valid usernames and the corresponding passwords. </p> </item> <tag><c><![CDATA[{password, string()}]]></c></tag> <item> - <p>Provide a global password that will authenticate any + <p>Provides a global password that authenticates any user. From a security perspective this option makes the server very vulnerable.</p> </item> - <tag><c><![CDATA[{pwdfun, fun/2}]]></c></tag> + + <tag><c><![CDATA[{preferred_algorithms, algs_list()}]]></c></tag> + <item> + <p>List of algorithms to use in the algorithm negotiation. The default <c>algs_list()</c> can + be obtained from <seealso marker="#default_algorithms/0">default_algorithms/0</seealso>. + </p> + <p>If an alg_entry() is missing in the algs_list(), the default value is used for that entry.</p> + <p>Here is an example of this option:</p> + <code> +{preferred_algorithms, + [{public_key,['ssh-rsa','ssh-dss']}, + {cipher,[{client2server,['aes128-ctr']}, + {server2client,['aes128-cbc','3des-cbc']}]}, + {mac,['hmac-sha2-256','hmac-sha1']}, + {compression,[none,zlib]} + ] +} +</code> + <p>The example specifies different algorithms in the two directions (client2server and server2client), + for cipher but specifies the same algorithms for mac and compression in both directions. + The kex (key exchange) is implicit but public_key is set explicitly.</p> + + <warning> + <p>Changing the values can make a connection less secure. Do not change unless you + know exactly what you are doing. If you do not understand the values then you + are not supposed to change them.</p> + </warning> + </item> + + <tag><c><![CDATA[{dh_gex_groups, [{Size=integer(),G=integer(),P=integer()}] | {file,filename()} {ssh_moduli_file,filename()} }]]></c></tag> + <item> + <p>Defines the groups the server may choose among when diffie-hellman-group-exchange is negotiated. + See RFC 4419 for details. The three variants of this option are: + </p> + <taglist> + <tag><c>{Size=integer(),G=integer(),P=integer()}</c></tag> + <item>The groups are given explicitly in this list. There may be several elements with the same <c>Size</c>. + In such a case, the server will choose one randomly in the negotiated Size. + </item> + <tag><c>{file,filename()}</c></tag> + <item>The file must have one or more three-tuples <c>{Size=integer(),G=integer(),P=integer()}</c> + terminated by a dot. The file is read when the daemon starts. + </item> + <tag><c>{ssh_moduli_file,filename()}</c></tag> + <item>The file must be in + <seealso marker="public_key:public_key#dh_gex_group/4">ssh-keygen moduli file format</seealso>. + The file is read when the daemon starts. + </item> + </taglist> + <p>The default list is fetched from the + <seealso marker="public_key:public_key#dh_gex_group/4">public_key</seealso> application. + </p> + </item> + + <tag><c><![CDATA[{dh_gex_limits,{Min=integer(),Max=integer()}}]]></c></tag> + <item> + <p>Limits what a client can ask for in diffie-hellman-group-exchange. + The limits will be + <c>{MaxUsed = min(MaxClient,Max), MinUsed = max(MinClient,Min)}</c> where <c>MaxClient</c> and + <c>MinClient</c> are the values proposed by a connecting client. + </p> + <p>The default value is <c>{0,infinity}</c>. + </p> + <p>If <c>MaxUsed < MinUsed</c> in a key exchange, it will fail with a disconnect. + </p> + <p>See RFC 4419 for the function of the Max and Min values.</p> + </item> + + <tag><c><![CDATA[{pwdfun, fun(User::string(), Password::string(), PeerAddress::{ip_adress(),port_number()}, State::any()) -> boolean() | disconnect | {boolean(),any()} }]]></c></tag> + <item> + <p>Provides a function for password validation. This could used for calling an external system or if + passwords should be stored as a hash. The fun returns: + </p> + <list type="bulleted"> + <item><c>true</c> if the user and password is valid and</item> + <item><c>false</c> otherwise.</item> + </list> + <p>This fun can also be used to make delays in authentication tries for example by calling + <seealso marker="stdlib:timer#sleep/1">timer:sleep/1</seealso>. To facilitate counting of failed tries + the <c>State</c> variable could be used. This state is per connection only. The first time the pwdfun + is called for a connection, the <c>State</c> variable has the value <c>undefined</c>. + The pwdfun can return - in addition to the values above - a new state + as: + </p> + <list type="bulleted"> + <item><c>{true, NewState:any()}</c> if the user and password is valid or</item> + <item><c>{false, NewState:any()}</c> if the user or password is invalid</item> + </list> + <p>A third usage is to block login attempts from a missbehaving peer. The <c>State</c> described above + can be used for this. In addition to the responses above, the following return value is introduced: + </p> + <list type="bulleted"> + <item><c>disconnect</c> if the connection should be closed immediately after sending a SSH_MSG_DISCONNECT + message.</item> + </list> + </item> + + <tag><c><![CDATA[{pwdfun, fun(User::string(), Password::string()) -> boolean()}]]></c></tag> <item> - <p>Provide a function for password validation. This is called - with user and password as strings, and should return + <p>Provides a function for password validation. This function is called + with user and password as strings, and returns <c><![CDATA[true]]></c> if the password is valid and <c><![CDATA[false]]></c> otherwise.</p> + <p>This option (<c>{pwdfun,fun/2}</c>) is the same as a subset of the previous + (<c>{pwdfun,fun/4}</c>). It is kept for compatibility.</p> + </item> + + <tag><c><![CDATA[{negotiation_timeout, integer()}]]></c></tag> + <item> + <p>Maximum time in milliseconds for the authentication negotiation. + Defaults to 120000 (2 minutes). If the client fails to log in within this time, + the connection is closed. + </p> + </item> + + <tag><c><![CDATA[{max_sessions, pos_integer()}]]></c></tag> + <item> + <p>The maximum number of simultaneous sessions that are accepted at any time + for this daemon. This includes sessions that are being authorized. + Thus, if set to <c>N</c>, and <c>N</c> clients have connected but not started + the login process, connection attempt <c>N+1</c> is aborted. + If <c>N</c> connections are authenticated and still logged in, no more logins + are accepted until one of the existing ones log out. + </p> + <p>The counter is per listening port. Thus, if two daemons are started, one with + <c>{max_sessions,N}</c> and the other with <c>{max_sessions,M}</c>, in total + <c>N+M</c> connections are accepted for the whole <c>ssh</c> application. + </p> + <p>Notice that if <c>parallel_login</c> is <c>false</c>, only one client + at a time can be in the authentication phase. + </p> + <p>By default, this option is not set. This means that the number is not limited. + </p> + </item> + + <tag><c><![CDATA[{max_channels, pos_integer()}]]></c></tag> + <item> + <p>The maximum number of channels with active remote subsystem that are accepted for + each connection to this daemon</p> + <p>By default, this option is not set. This means that the number is not limited. + </p> + </item> + + + <tag><c><![CDATA[{parallel_login, boolean()}]]></c></tag> + <item> + <p>If set to false (the default value), only one login is handled at a time. + If set to true, an unlimited number of login attempts are allowed simultaneously. + </p> + <p>If the <c>max_sessions</c> option is set to <c>N</c> and <c>parallel_login</c> + is set to <c>true</c>, the maximum number of simultaneous login attempts at any time is + limited to <c>N-K</c>, where <c>K</c> is the number of authenticated connections present + at this daemon. + </p> + <warning> + <p>Do not enable <c>parallel_logins</c> without protecting the server by other means, + for example, by the <c>max_sessions</c> option or a firewall configuration. If set to + <c>true</c>, there is no protection against DOS attacks.</p> + </warning> + </item> + + <tag><c><![CDATA[{minimal_remote_max_packet_size, non_negative_integer()}]]></c></tag> + <item> + <p>The least maximum packet size that the daemon will accept in channel open requests from the client. The default value is 0. + </p> + </item> + + <tag><c><![CDATA[{id_string, random | string()}]]></c></tag> + <item> + <p>The string the daemon will present to a connecting peer initially. The default value is "Erlang/VSN" where VSN is the ssh application version number. + </p> + <p>The value <c>random</c> will cause a random string to be created at each connection attempt. This is to make it a bit more difficult for a malicious peer to find the ssh software brand and version. + </p> + </item> + + <tag><c><![CDATA[{key_cb, key_cb()}]]></c></tag> + <item> + <p>Module implementing the behaviour <seealso + marker="ssh_server_key_api">ssh_server_key_api</seealso>. Can be used to + customize the handling of public keys. If callback options are provided + along with the module name, they are made available to the callback + module via the options passed to it under the key 'key_cb_private'. + </p> + </item> + + <tag><c>{profile, atom()}</c></tag> + <item> + <p>Used together with <c>ip-address</c> and <c>port</c> to + uniquely identify a ssh daemon. This can be useful in a + virtualized environment, where there can be more that one + server that has the same <c>ip-address</c> and + <c>port</c>. If this property is not explicitly set, it is + assumed that the the <c>ip-address</c> and <c>port</c> + uniquely identifies the SSH daemon. + </p> </item> + <tag><c><![CDATA[{fd, file_descriptor()}]]></c></tag> <item> - <p>Allow an existing file-descriptor to be used - (simply passed on to the transport protocol).</p></item> - <tag><c><![CDATA[{ip_v6_disabled, boolean()}]]></c></tag> + <p>Allows an existing file-descriptor to be used + (passed on to the transport protocol).</p></item> + <tag><c><![CDATA[{failfun, fun(User::string(), + PeerAddress::ip_address(), Reason::term()) -> _}]]></c></tag> + <item> + <p>Provides a fun to implement your own logging when a user fails to authenticate.</p> + </item> + <tag><c><![CDATA[{connectfun, fun(User::string(), PeerAddress::ip_address(), + Method::string()) ->_}]]></c></tag> + <item> + <p>Provides a fun to implement your own logging when a user authenticates to the server.</p> + </item> + <tag><c><![CDATA[{disconnectfun, fun(Reason:term()) -> _}]]></c></tag> <item> - <p>Determines if SSH shall use IPv6 or not (only used when - HostAddress is set to any).</p></item> - </taglist> + <p>Provides a fun to implement your own logging when a user disconnects from the server.</p> + </item> + + <tag><c><![CDATA[{unexpectedfun, fun(Message:term(), Peer) -> report | skip }]]></c></tag> + <item> + <p>Provides a fun to implement your own logging or other action when an unexpected message arrives. + If the fun returns <c>report</c> the usual info report is issued but if <c>skip</c> is returned no + report is generated.</p> + <p><c>Peer</c> is in the format of <c>{Host,Port}</c>.</p> + </item> + + <tag><c><![CDATA[{ssh_msg_debug_fun, fun(ConnectionRef::ssh_connection_ref(), AlwaysDisplay::boolean(), Msg::binary(), LanguageTag::binary()) -> _}]]></c></tag> + <item> + <p>Provide a fun to implement your own logging of the SSH message SSH_MSG_DEBUG. The last three parameters are from the message, see RFC4253, section 11.3. The <c>ConnectionRef</c> is the reference to the connection on which the message arrived. The return value from the fun is not checked.</p> + <p>The default behaviour is ignore the message. + To get a printout for each message with <c>AlwaysDisplay = true</c>, use for example <c>{ssh_msg_debug_fun, fun(_,true,M,_)-> io:format("DEBUG: ~p~n", [M]) end}</c></p> + </item> + + </taglist> + </desc> + </func> + + <func> + <name>daemon_info(Daemon) -> {ok, [{port,Port}]} | {error,Error}</name> + <fsummary>Get info about a daemon</fsummary> + <type> + <v>Port = integer()</v> + <v>Error = bad_daemon_ref</v> + </type> + <desc> + <p>Returns a key-value list with information about the daemon. For now, only the listening port is returned. This is intended for the case the daemon is started with the port set to 0.</p> + </desc> + </func> + + <func> + <name>default_algorithms() -> algs_list()</name> + <fsummary>Get a list declaring the supported algorithms</fsummary> + <desc> + <p>Returns a key-value list, where the keys are the different types of algorithms and the values are the + algorithms themselves. An example:</p> + <code> +20> ssh:default_algorithms(). +[{kex,['diffie-hellman-group1-sha1']}, + {public_key,['ssh-rsa','ssh-dss']}, + {cipher,[{client2server,['aes128-ctr','aes128-cbc','3des-cbc']}, + {server2client,['aes128-ctr','aes128-cbc','3des-cbc']}]}, + {mac,[{client2server,['hmac-sha2-256','hmac-sha1']}, + {server2client,['hmac-sha2-256','hmac-sha1']}]}, + {compression,[{client2server,[none,zlib]}, + {server2client,[none,zlib]}]}] +21> +</code> </desc> </func> <func> <name>shell(Host) -> </name> <name>shell(Host, Option) -> </name> - <name>shell(Host, Port, Option) -> _</name> - <fsummary> </fsummary> + <name>shell(Host, Port, Option) -> </name> + <name>shell(TcpSocket) -> _</name> + <fsummary>Starts an interactive shell over an SSH server.</fsummary> <type> - <v> Host = string()</v> - <v> Port = integer()</v> - <v> Options - see ssh:connect/3</v> + <v>Host = string()</v> + <v>Port = integer()</v> + <v>Options - see ssh:connect/3</v> + <v>TcpSocket = port()</v> + <d>The socket is supposed to be from <seealso marker="kernel:gen_tcp#connect-3">gen_tcp:connect</seealso> or <seealso marker="kernel:gen_tcp#accept-1">gen_tcp:accept</seealso> with option <c>{active,false}</c></d> </type> <desc> - <p>Starts an interactive shell to an SSH server on the + <p>Starts an interactive shell over an SSH server on the given <c>Host</c>. The function waits for user input, - and will not return until the remote shell is ended (e.g. on + and does not return until the remote shell is ended (that is, exit from the shell). </p> </desc> @@ -331,26 +757,29 @@ <func> <name>start() -> </name> <name>start(Type) -> ok | {error, Reason}</name> - <fsummary>Starts the Ssh application. </fsummary> + <fsummary>Starts the SSH application.</fsummary> <type> <v>Type = permanent | transient | temporary</v> <v>Reason = term() </v> </type> <desc> - <p>Starts the Ssh application. Default type - is temporary. See also - <seealso marker="kernel:application">application(3)</seealso> - Requires that the crypto application has been started. - </p> + <p>Utility function that starts the applications <c>crypto</c>, <c>public_key</c>, + and <c>ssh</c>. Default type is <c>temporary</c>. + For more information, see the <seealso marker="kernel:application">application(3)</seealso> + manual page in Kernel.</p> </desc> </func> <func> - <name>stop() -> ok </name> - <fsummary>Stops the Ssh application.</fsummary> + <name>stop() -> ok | {error, Reason}</name> + <fsummary>Stops the <c>ssh</c> application.</fsummary> + <type> + <v>Reason = term()</v> + </type> <desc> - <p>Stops the Ssh application. See also - <seealso marker="kernel:application">application(3)</seealso></p> + <p>Stops the <c>ssh</c> application. + For more information, see the <seealso marker="kernel:application">application(3)</seealso> + manual page in Kernel.</p> </desc> </func> @@ -374,7 +803,7 @@ <name>stop_listener(DaemonRef) -> </name> <name>stop_listener(Address, Port) -> ok </name> <fsummary>Stops the listener, but leaves existing connections started - by the listener up and running.</fsummary> + by the listener operational.</fsummary> <type> <v>DaemonRef = ssh_daemon_ref()</v> <v>Address = ip_address()</v> @@ -382,7 +811,7 @@ </type> <desc> <p>Stops the listener, but leaves existing connections started - by the listener up and running.</p> + by the listener operational.</p> </desc> </func> diff --git a/lib/ssh/doc/src/ssh_app.xml b/lib/ssh/doc/src/ssh_app.xml new file mode 100644 index 0000000000..5cc4c24889 --- /dev/null +++ b/lib/ssh/doc/src/ssh_app.xml @@ -0,0 +1,319 @@ +<?xml version="1.0" encoding="utf-8" ?> +<!DOCTYPE appref SYSTEM "appref.dtd"> + +<appref> + <header> + <copyright> + <year>2012</year><year>2016</year> + <holder>Ericsson AB. All Rights Reserved.</holder> + </copyright> + <legalnotice> + Licensed under the Apache License, Version 2.0 (the "License"); + you may not use this file except in compliance with the License. + You may obtain a copy of the License at + + http://www.apache.org/licenses/LICENSE-2.0 + + Unless required by applicable law or agreed to in writing, software + distributed under the License is distributed on an "AS IS" BASIS, + WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + See the License for the specific language governing permissions and + limitations under the License. + </legalnotice> + + <title>SSH</title> + <prepared></prepared> + <docno></docno> + <checked></checked> + <date></date> + <rev></rev> + <file>ssh_app.xml</file> + </header> + <app>SSH</app> + <appsummary>The ssh application implements the Secure Shell (SSH) protocol and + provides an SSH File Transfer Protocol (SFTP) client and server.</appsummary> + <description> + <p>The <c>ssh</c> application is an implementation of the SSH protocol in Erlang. + <c>ssh</c> offers API functions to write customized SSH clients and servers as well as + making the Erlang shell available over SSH. An SFTP client, <c>ssh_sftp</c>, and server, + <c>ssh_sftpd</c>, are also included.</p> + </description> + + <section> + <title>DEPENDENCIES</title> + <p>The <c>ssh</c> application uses the applications + <seealso marker="public_key:public_key">public_key</seealso> and + <seealso marker="crypto:crypto">crypto</seealso> + to handle public keys and encryption. Hence, these + applications must be loaded for the <c>ssh</c> application to work. In + an embedded environment this means that they must be started with + <seealso marker="kernel:application#start/1">application:start/1,2</seealso> before the + <c>ssh</c> application is started. + </p> + </section> + + <section> + <title>CONFIGURATION</title> + + <p>The <c>ssh</c> application does not have an application- + specific configuration file, as described in <seealso marker="kernel:application">application(3)</seealso>. + However, by default it use the following configuration files + from OpenSSH:</p> + <list type="bulleted"> + <item><c>known_hosts</c></item> + <item><c>authorized_keys</c></item> + <item><c>authorized_keys2</c></item> + <item><c>id_dsa</c></item> + <item><c>id_rsa</c></item> + <item><c>id_ecdsa</c></item> + <item><c>ssh_host_dsa_key</c></item> + <item><c>ssh_host_rsa_key</c></item> + <item><c>ssh_host_ecdsa_key</c></item> + </list> + <p>By default, <c>ssh</c> looks for <c>id_dsa</c>, <c>id_rsa</c>, + <c>id_ecdsa_key</c>, + <c>known_hosts</c>, and <c>authorized_keys</c> in ~/.ssh, + and for the host key files in <c>/etc/ssh</c>. These locations can be changed + by the options <c>user_dir</c> and <c>system_dir</c>. + </p> + <p>Public key handling can also be customized through a callback module that + implements the behaviors + <seealso marker="ssh_client_key_api">ssh_client_key_api</seealso> and + <seealso marker="ssh_server_key_api">ssh_server_key_api</seealso>. + </p> + + </section> + <section> + <title>Public Keys</title> + <p><c>id_dsa</c>, <c>id_rsa</c> and <c>id_ecdsa</c> are the users private key files. + Notice that the public key is part of the private key so the <c>ssh</c> + application does not use the <c>id_<*>.pub</c> files. These are + for the user's convenience when it is needed to convey the user's + public key. + </p> + </section> + <section> + <title>Known Hosts</title> + <p>The <c>known_hosts</c> file contains a list of approved servers and + their public keys. Once a server is listed, it can be verified + without user interaction. + </p> + </section> + <section> + <title>Authorized Keys</title> + <p>The <c>authorized_key</c> file keeps track of the user's authorized + public keys. The most common use of this file is to let users + log in without entering their password, which is supported by the + Erlang <c>ssh</c> daemon. + </p> + </section> + <section> + <title>Host Keys</title> + <p>RSA and DSA host keys are supported and are + expected to be found in files named <c>ssh_host_rsa_key</c>, + <c>ssh_host_dsa_key</c> and <c>ssh_host_ecdsa_key</c>. + </p> + </section> + <section> + <title>ERROR LOGGER AND EVENT HANDLERS</title> + <p>The <c>ssh</c> application uses the default <seealso marker="kernel:error_logger">OTP error logger</seealso> to log unexpected errors or print information about special events.</p> + </section> + + <section> + <marker id="supported"/> + <title>SUPPORTED SPECIFICATIONS AND STANDARDS</title> + <p>The supported SSH version is 2.0.</p> + </section> + <section> + <title>Algorithms</title> + <p>The actual set of algorithms may vary depending on which OpenSSL crypto library that is installed on the machine. + For the list on a particular installation, use the command + <seealso marker="ssh:ssh#default_algorithms/0">ssh:default_algorithms/0</seealso>. + The user may override the default algorithm configuration both on the server side and the client side. + See the option <c>preferred_algorithms</c> in the <seealso marker="ssh:ssh#daemon/1">ssh:daemon/1,2,3</seealso> and + <seealso marker="ssh:ssh#connect/3">ssh:connect/3,4</seealso> functions. + </p> + + <p>Supported algorithms are:</p> + + <taglist> + <tag>Key exchange algorithms</tag> + <item> + <list type="bulleted"> + <item>ecdh-sha2-nistp256</item> + <item>ecdh-sha2-nistp384</item> + <item>ecdh-sha2-nistp521</item> + <item>diffie-hellman-group-exchange-sha1</item> + <item>diffie-hellman-group-exchange-sha256</item> + <item>diffie-hellman-group14-sha1</item> + <item>diffie-hellman-group1-sha1</item> + </list> + </item> + + <tag>Public key algorithms</tag> + <item> + <list type="bulleted"> + <item>ecdsa-sha2-nistp256</item> + <item>ecdsa-sha2-nistp384</item> + <item>ecdsa-sha2-nistp521</item> + <item>ssh-rsa</item> + <item>ssh-dss</item> + </list> + </item> + + <tag>MAC algorithms</tag> + <item> + <list type="bulleted"> + <item>hmac-sha2-256</item> + <item>hmac-sha2-512</item> + <item>hmac-sha1</item> + </list> + </item> + + <tag>Encryption algorithms (ciphers)</tag> + <item> + <list type="bulleted"> + <item>[email protected] (AEAD_AES_128_GCM)</item> + <item>[email protected] (AEAD_AES_256_GCM)</item> + <item>aes128-ctr</item> + <item>aes192-ctr</item> + <item>aes256-ctr</item> + <item>aes128-cbc</item> + <item>3des-cbc</item> + </list> + <p>Following the internet de-facto standard, the cipher and mac algorithm AEAD_AES_128_GCM is selected when the + cipher [email protected] is negotiated. The cipher and mac algorithm AEAD_AES_256_GCM is selected when the + cipher [email protected] is negotiated. + </p> + <p>See the text at the description of <seealso marker="#rfc5647_note">the rfc 5647 further down</seealso> + for more information. + </p> + </item> + + <tag>Compression algorithms</tag> + <item> + <list type="bulleted"> + <item>none</item> + <item>[email protected]</item> + <item>zlib</item> + </list> + </item> + </taglist> + </section> + <section> + <title>Unicode support</title> + <p>Unicode filenames are supported if the emulator and the underlaying OS support it. See section DESCRIPTION in the + <seealso marker="kernel:file">file</seealso> manual page in Kernel for information about this subject. + </p> + <p>The shell and the cli both support unicode. + </p> + </section> + + <section> + <title>Rfcs</title> + <p>The following rfc:s are supported:</p> + <list type="bulleted"> + <item><url href="https://tools.ietf.org/html/rfc4251">RFC 4251</url>, The Secure Shell (SSH) Protocol Architecture. + <p>Except</p> + <list type="bulleted"> + <item>9.4.6 Host-Based Authentication</item> + <item>9.5.2 Proxy Forwarding</item> + <item>9.5.3 X11 Forwarding</item> + </list> + <p/> + </item> + + <item><url href="https://tools.ietf.org/html/rfc4252">RFC 4252</url>, The Secure Shell (SSH) Authentication Protocol. + <p>Except</p> + <list type="bulleted"> + <item>9. Host-Based Authentication: "hostbased"</item> + </list> + <p/> + </item> + + <item><url href="https://tools.ietf.org/html/rfc4253">RFC 4253</url>, The Secure Shell (SSH) Transport Layer Protocol. + <p></p> + </item> + + <item><url href="https://tools.ietf.org/html/rfc4254">RFC 4254</url>, The Secure Shell (SSH) Connection Protocol. + <p>Except</p> + <list type="bulleted"> + <item>6.3. X11 Forwarding</item> + <item>7. TCP/IP Port Forwarding</item> + </list> + <p/> + </item> + + <item><url href="https://tools.ietf.org/html/rfc4256">RFC 4256</url>, Generic Message Exchange Authentication for + the Secure Shell Protocol (SSH). + <p>Except</p> + <list type="bulleted"> + <item><c>num-prompts > 1</c></item> + <item>password changing</item> + <item>other identification methods than userid-password</item> + </list> + <p/> + </item> + + <item><url href="https://tools.ietf.org/html/rfc4419">RFC 4419</url>, Diffie-Hellman Group Exchange for + the Secure Shell (SSH) Transport Layer Protocol. + <p/> + </item> + + <item><url href="https://tools.ietf.org/html/rfc4716">RFC 4716</url>, The Secure Shell (SSH) Public Key File Format. + <p/> + </item> + + <item><url href="https://tools.ietf.org/html/rfc5647">RFC 5647</url>, AES Galois Counter Mode for + the Secure Shell Transport Layer Protocol. + <p><marker id="rfc5647_note"/>There is an ambiguity in the synchronized selection of cipher and mac algorithm. + This is resolved by OpenSSH in the ciphers [email protected] and [email protected] which are implemented. + If the explicit ciphers and macs AEAD_AES_128_GCM or AEAD_AES_256_GCM are needed, + they could be enabled with the option preferred_algorithms. + </p> + <warning> + <p> + If the client or the server is not Erlang/OTP, it is the users responsibility to check that + other implementation has the same interpretation of AEAD_AES_*_GCM as the Erlang/OTP SSH before + enabling them. The aes*[email protected] variants are always safe to use since they lack the + ambiguity. + </p> + </warning> + <p>The second paragraph in section 5.1 is resolved as:</p> + <list type="ordered"> + <item>If the negotiated cipher is AEAD_AES_128_GCM, the mac algorithm is set to AEAD_AES_128_GCM.</item> + <item>If the negotiated cipher is AEAD_AES_256_GCM, the mac algorithm is set to AEAD_AES_256_GCM.</item> + <item>If the mac algorithm is AEAD_AES_128_GCM, the cipher is set to AEAD_AES_128_GCM.</item> + <item>If the mac algorithm is AEAD_AES_256_GCM, the cipher is set to AEAD_AES_256_GCM.</item> + </list> + <p>The first rule that matches when read in order from the top is applied</p> + </item> + + <item><url href="https://tools.ietf.org/html/rfc5656">RFC 5656</url>, Elliptic Curve Algorithm Integration in + the Secure Shell Transport Layer. + <p>Except</p> + <list type="bulleted"> + <item>5. ECMQV Key Exchange</item> + <item>6.4. ECMQV Key Exchange and Verification Method Name</item> + <item>7.2. ECMQV Message Numbers</item> + <item>10.2. Recommended Curves</item> + </list> + <p/> + </item> + + <item><url href="https://tools.ietf.org/html/rfc6668">RFC 6668</url>, SHA-2 Data Integrity Verification for + the Secure Shell (SSH) Transport Layer Protocol + <p>Comment: Defines hmac-sha2-256 and hmac-sha2-512 + </p> + </item> + + </list> + + </section> + + <section> + <title>SEE ALSO</title> + <p><seealso marker="kernel:application">application(3)</seealso></p> + </section> + +</appref> diff --git a/lib/ssh/doc/src/ssh_channel.xml b/lib/ssh/doc/src/ssh_channel.xml index c2b7aa94a5..7b598494f7 100644 --- a/lib/ssh/doc/src/ssh_channel.xml +++ b/lib/ssh/doc/src/ssh_channel.xml @@ -1,86 +1,108 @@ -<?xml version="1.0" encoding="latin1" ?> +<?xml version="1.0" encoding="utf-8" ?> <!DOCTYPE erlref SYSTEM "erlref.dtd"> <erlref> <header> <copyright> <year>2009</year> - <year>2009</year> + <year>2016</year> <holder>Ericsson AB, All Rights Reserved</holder> </copyright> <legalnotice> - The contents of this file are subject to the Erlang Public License, - Version 1.1, (the "License"); you may not use this file except in - compliance with the License. You should have received a copy of the - Erlang Public License along with this software. If not, it can be - retrieved online at http://www.erlang.org/. + Licensed under the Apache License, Version 2.0 (the "License"); + you may not use this file except in compliance with the License. + You may obtain a copy of the License at + + http://www.apache.org/licenses/LICENSE-2.0 - Software distributed under the License is distributed on an "AS IS" - basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See - the License for the specific language governing rights and limitations - under the License. + Unless required by applicable law or agreed to in writing, software + distributed under the License is distributed on an "AS IS" BASIS, + WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + See the License for the specific language governing permissions and + limitations under the License. The Initial Developer of the Original Code is Ericsson AB. </legalnotice> - <title>ssh_channel</title> - <prepared>Ingela Anderton Andin</prepared> - <responsible></responsible> + <prepared></prepared> <docno></docno> - <approved></approved> - <checked></checked> <date></date> <rev></rev> </header> <module>ssh_channel</module> - <modulesummary>Generic Ssh Channel Behavior + <modulesummary>-behaviour(ssh_channel). </modulesummary> <description> - <p>Ssh services are implemented as channels that are multiplexed - over an ssh connection and communicates via the ssh connection - protocol. This module provides a callback API that takes care of - generic channel aspects such as flow control and close messages - and lets the callback functions take care of the service specific - parts. + <p>SSH services (clients and servers) are implemented as channels + that are multiplexed over an SSH connection and communicates over + the <url href="http://www.ietf.org/rfc/rfc4254.txt"> SSH + Connection Protocol</url>. This module provides a callback API + that takes care of generic channel aspects, such as flow control + and close messages. It lets the callback functions take care of + the service (application) specific parts. This behavior also ensures + that the channel process honors the principal of an OTP-process so + that it can be part of a supervisor tree. This is a requirement of + channel processes implementing a subsystem that will be added to + the <c>ssh</c> applications supervisor tree. </p> + + <note><p>When implementing an <c>ssh</c> subsystem, use + <c>-behaviour(ssh_daemon_channel)</c> instead of <c>-behaviour(ssh_channel)</c>. + The reason is that the only relevant callback functions for subsystems are + <c>init/1</c>, <c>handle_ssh_msg/2</c>, <c>handle_msg/2</c>, and <c>terminate/2</c>. + So, the <c>ssh_daemon_channel</c> behaviour is a limited version of the + <c>ssh_channel</c> behaviour. + </p></note> </description> <section> - <title>COMMON DATA TYPES </title> + <title>DATA TYPES</title> - <p>Type definitions that are used more than once in this module - and/or abstractions to indicate the intended use of the data - type:</p> + <p>Type definitions that are used more than once in this module, + or abstractions to indicate the intended use of the data + type, or both:</p> - <p><c>boolean() = true | false </c></p> - <p><c>string() = list of ASCII characters</c></p> - <p><c>timeout() = infinity | integer() - in milliseconds.</c></p> - <p><c>ssh_connection_ref() - opaque to the user returned by - ssh:connect/3 or sent to a ssh channel process</c></p> - <p><c>ssh_channel_id() = integer() </c></p> - <p><c>ssh_data_type_code() = 1 ("stderr") | 0 ("normal") are - currently valid values see RFC 4254 section 5.2.</c></p> + <taglist> + <tag><c>boolean() =</c></tag> + <item><p><c>true | false</c></p></item> + <tag><c>string() =</c></tag> + <item><p>list of ASCII characters</p></item> + <tag><c>timeout() =</c></tag> + <item><p><c>infinity | integer()</c> in milliseconds</p></item> + <tag><c>ssh_connection_ref() =</c></tag> + <item><p>opaque() -as returned by + <c>ssh:connect/3</c> or sent to an SSH channel process</p></item> + <tag><c>ssh_channel_id() =</c></tag> + <item><p><c>integer()</c></p></item> + <tag><c>ssh_data_type_code() =</c></tag> + <item><p><c>1</c> ("stderr") | <c>0</c> ("normal") are + the valid values, + see <url href="http://www.ietf.org/rfc/rfc4254.txt">RFC 4254</url> + Section 5.2</p></item> + </taglist> </section> <funcs> <func> <name>call(ChannelRef, Msg) -></name> <name>call(ChannelRef, Msg, Timeout) -> Reply | {error, Reason}</name> - <fsummary> Makes a synchronous call to a channel.</fsummary> + <fsummary>Makes a synchronous call to a channel.</fsummary> <type> <v>ChannelRef = pid() </v> - <d>As returned by start_link/4 </d> - <v>Msg = term() </v> - <v>Timeout = timeout() </v> - <v>Reply = term() </v> - <v>Reason = closed | timeout </v> + <d>As returned by <seealso marker = "#start_link-4">ssh_channel:start_link/4</seealso></d> + <v>Msg = term()</v> + <v>Timeout = timeout()</v> + <v>Reply = term()</v> + <v>Reason = closed | timeout</v> + </type> <desc> <p>Makes a synchronous call to the channel process by sending - a message and waiting until a reply arrives or a timeout - occurs. The channel will call - <c>CallbackModule:handle_call/3</c> to handle the message. - If the channel process does not exist <c>{error, closed}</c> is returned. + a message and waiting until a reply arrives, or a time-out + occurs. The channel calls <seealso marker = + "#Module:handle_call-3">Module:handle_call/3</seealso> + to handle the message. If the channel process does not exist, + <c>{error, closed}</c> is returned. </p> </desc> </func> @@ -90,43 +112,48 @@ <fsummary>Sends an asynchronous message to the channel ChannelRef and returns ok.</fsummary> <type> - <v>ChannelRef = pid() </v> - <d>As returned by start_link/4 </d> - <v>Msg = term() </v> + <v>ChannelRef = pid()</v> + <d>As returned by <seealso marker = "#start_link-4">ssh_channel:start_link/4</seealso></d> + <v>Msg = term()</v> </type> <desc> <p>Sends an asynchronous message to the channel process and returns ok immediately, ignoring if the destination node or - channel process does not exist. The channel will call - <c>CallbackModule:handle_cast/2</c> to handle the message. + channel process does not exist. The channel calls + <seealso marker = "#Module:handle_cast-2">Module:handle_cast/2</seealso> + to handle the message. </p> </desc> </func> <func> <name>enter_loop(State) -> _ </name> - <fsummary> Makes an existing process into a ssh_channel process. </fsummary> + <fsummary>Makes an existing process an ssh_channel process.</fsummary> <type> - <v> State = term() - as returned by ssh_channel:init/1</v> + <v>State = term()</v> + <d>as returned by <seealso marker = "#init-1">ssh_channel:init/1</seealso></d> </type> <desc> - <p> Makes an existing process into a <c>ssh_channel</c> - process. Does not return, instead the calling process will - enter the <c>ssh_channel</c> process receive loop and become a - <c>ssh_channel process.</c> The process must have been started using - one of the start functions in proc_lib, see <seealso - marker="stdlib:proc_lib">proc_lib(3)</seealso>. The - user is responsible for any initialization of the process - and needs to call ssh_channel:init/1. + <p>Makes an existing process an <c>ssh_channel</c> + process. Does not return, instead the calling process + enters the <c>ssh_channel</c> process receive loop and become an + <c>ssh_channel process</c>. The process must have been started using + one of the start functions in <c>proc_lib</c>, see the <seealso + marker="stdlib:proc_lib">proc_lib(3)</seealso> manual page in STDLIB. + The user is responsible for any initialization of the process + and must call <seealso marker = "#init-1">ssh_channel:init/1</seealso>. </p> </desc> </func> <func> <name>init(Options) -> {ok, State} | {ok, State, Timeout} | {stop, Reason} </name> - <fsummary> Initiates a ssh_channel process.</fsummary> + <fsummary>Initiates an <c>ssh_channel</c> process.</fsummary> <type> - <v> Options = [{Option, Value}]</v> + <v>Options = [{Option, Value}]</v> + <v>State = term()</v> + <v>Timeout = timeout()</v> + <v>Reason = term()</v> </type> <desc> <p> @@ -134,45 +161,47 @@ </p> <taglist> <tag><c><![CDATA[{channel_cb, atom()}]]></c></tag> - <item>The module that implements the channel behavior.</item> + <item><p>The module that implements the channel behaviour.</p></item> <tag><c><![CDATA[{init_args(), list()}]]></c></tag> - <item> The list of arguments to the callback modules - init function.</item> + <item><p>The list of arguments to the <c>init</c> function of the callback module.</p></item> <tag><c><![CDATA[{cm, connection_ref()}]]></c></tag> - <item> Reference to the ssh connection.</item> + <item><p>Reference to the <c>ssh</c> connection as returned by <seealso + marker="ssh#connect-3">ssh:connect/3</seealso></p></item> <tag><c><![CDATA[{channel_id, channel_id()}]]></c></tag> - <item> Id of the ssh channel.</item> + <item><p>Id of the <c>ssh</c> channel.</p></item> </taglist> - <note><p>This function is normally not called by the user, it is - only needed if for some reason the channel process needs - to be started with help of <c>proc_lib</c> instead calling - <c>ssh_channel:start/4</c> or <c>ssh_channel:start_link/4</c> </p> + <note><p>This function is normally not called by the + user. The user only needs to call if the + channel process needs to be started with help of + <c>proc_lib</c> instead of calling + <c>ssh_channel:start/4</c> or + <c>ssh_channel:start_link/4</c>.</p> </note> </desc> </func> <func> <name>reply(Client, Reply) -> _</name> - <fsummary>Send a reply to a client.</fsummary> + <fsummary>Sends a reply to a client.</fsummary> <type> - <v>Client - opaque to the user, see explanation below</v> + <v>Client = opaque()</v> <v>Reply = term()</v> </type> <desc> - <p>This function can be used by a channel to explicitly send a + <p>This function can be used by a channel to send a reply to a client that called <c>call/[2,3]</c> when the reply cannot be defined in the return value of - <c>CallbackModule:handle_call/3</c>.</p> + <seealso marker ="#Module:handle_call-3">Module:handle_call/3</seealso>.</p> <p><c>Client</c> must be the <c>From</c> argument provided to the callback function <c>handle_call/3</c>. <c>Reply</c> is an arbitrary term, - which will be given back to the client as the return value of - <c>ssh_channel:call/[2,3].</c></p> + which is given back to the client as the return value of + <seealso marker="#call-2">ssh_channel:call/[2,3].</seealso></p> </desc> </func> @@ -180,23 +209,25 @@ <name>start(SshConnection, ChannelId, ChannelCb, CbInitArgs) -> </name> <name>start_link(SshConnection, ChannelId, ChannelCb, CbInitArgs) -> {ok, ChannelRef} | {error, Reason}</name> - <fsummary> Starts a processes that handles a ssh channel. </fsummary> + <fsummary>Starts a process that handles an SSH channel.</fsummary> <type> <v>SshConnection = ssh_connection_ref()</v> - <v>ChannelId = ssh_channel_id() </v> - <d> As returned by ssh_connection:session_channel/[2,4]</d> + <v>ChannelId = ssh_channel_id()</v> + <d>As returned by + <seealso marker ="ssh_connection#session_channel/2"> + ssh_connection:session_channel/[2,4]</seealso>.</d> <v>ChannelCb = atom()</v> - <d> The name of the module implementing the service specific parts + <d>Name of the module implementing the service-specific parts of the channel.</d> <v>CbInitArgs = [term()]</v> - <d>Argument list for the init function in the callback module. </d> + <d>Argument list for the <c>init</c> function in the callback module.</d> <v>ChannelRef = pid()</v> </type> <desc> - <p>Starts a processes that handles a ssh channel. Will be - called internally by the ssh daemon or explicitly by the ssh - client implementations. A channel process traps exit signals - by default. + <p>Starts a process that handles an SSH channel. It is + called internally, by the <c>ssh</c> daemon, or explicitly by the <c>ssh</c> + client implementations. The behavior sets the + <c>trap_exit</c> flag to <c>true</c>. </p> </desc> </func> @@ -204,313 +235,205 @@ </funcs> <section> - <title>CALLBACK FUNCTIONS</title> - - <p>The functions init/1, terminate/2, handle_ssh_msg/2 and - handle_msg/2 are the functions that are required to provide the - implementation for a server side channel, such as a ssh subsystem - channel that can be plugged into the erlang ssh daemon see - <seealso marker="ssh">ssh:daemon/[2, 3]</seealso>. The - handle_call/3, handle_cast/2 code_change/3 and enter_loop/1 - functions are only relevant when implementing a client side - channel.</p> - </section> - - <section> <marker id="cb_timeouts"></marker> - <title> CALLBACK TIMEOUTS</title> - <p> If an integer timeout value is provided in a return value of - one of the callback functions, a timeout will occur unless a - message is received within <c>Timeout</c> milliseconds. A timeout - is represented by the atom <c>timeout</c> which should be handled - by the <seealso marker="#handle_msg">handle_msg/2</seealso> - callback function. The atom infinity can be used to wait - indefinitely, this is the default value. </p> + <title>CALLBACK TIME-OUTS</title> + + <p>The time-out values that can be returned by the callback functions + have the same semantics as in a <seealso marker="stdlib:gen_server">gen_server</seealso>. + If the time-out occurs, <seealso marker="#Module:handle_msg-2">handle_msg/2</seealso> + is called as <c>handle_msg(timeout, State)</c>.</p> </section> <funcs> <func> - <name>CallbackModule:code_change(OldVsn, State, Extra) -> {ok, + <name>Module:code_change(OldVsn, State, Extra) -> {ok, NewState}</name> - <fsummary> Converts process state when code is changed.</fsummary> + <fsummary>Converts process state when code is changed.</fsummary> <type> - <v> Converts process state when code is changed.</v> + <v>OldVsn = term()</v> + <d>In the case of an upgrade, <c>OldVsn</c> is <c>Vsn</c>, and + in the case of a downgrade, <c>OldVsn</c> is + <c>{down,Vsn}</c>. <c>Vsn</c> is defined by the <c>vsn</c> + attribute(s) of the old version of the callback module + <c>Module</c>. If no such attribute is defined, the version is + the checksum of the BEAM file.</d> + <v>State = term()</v> + <d>Internal state of the channel.</d> + <v>Extra = term()</v> + <d>Passed "as-is" from the <c>{advanced,Extra}</c> + part of the update instruction.</d> </type> <desc> - <p>This function is called by a client side channel when it - should update its internal state during a release - upgrade/downgrade, i.e. when the instruction - <c>{update,Module,Change,...}</c> where - <c>Change={advanced,Extra}</c> is given in the <c>appup</c> - file. See <seealso - marker="doc/design_principles:release_handling#instr">OTP - Design Principles</seealso> for more information. Any new - connection will benefit from a server side upgrade but - already started connections on the server side will not be - affected. - </p> + <p>Converts process state when code is changed.</p> + + <p>This function is called by a client-side channel when it + is to update its internal state during a release + upgrade or downgrade, that is, when the instruction + <c>{update,Module,Change,...}</c>, where + <c>Change={advanced,Extra}</c>, is given in the <c>appup</c> + file. For more information, refer to Section 9.11.6 + Release Handling Instructions in the + <seealso marker="doc/design_principles:release_handling#instr">System Documentation</seealso>. + </p> - <note><p>If there are long lived ssh connections and more - than one upgrade in a short time this may cause the old - connections to fail as only two versions of the code may - be loaded simultaneously.</p></note> + <note><p>Soft upgrade according to the OTP release concept + is not straight forward for the server side, as subsystem + channel processes are spawned by the <c>ssh</c> application and + hence added to its supervisor tree. The subsystem channels can + be upgraded when upgrading the user application, if the callback + functions can handle two versions of the state, but this function + cannot be used in the normal way.</p> + </note> - <p>In the case of an upgrade, <c>OldVsn</c> is <c>Vsn</c>, and - in the case of a downgrade, <c>OldVsn</c> is - <c>{down,Vsn}</c>. <c>Vsn</c> is defined by the <c>vsn</c> - attribute(s) of the old version of the callback module - <c>Module</c>. If no such attribute is defined, the version - is the checksum of the BEAM file.</p> - <p><c>State</c> is the internal state of the channel.</p> - <p><c>Extra</c> is passed as-is from the <c>{advanced,Extra}</c> - part of the update instruction.</p> - <p>The function should return the updated internal state.</p> </desc> </func> <func> - <name>CallbackModule:init(Args) -> {ok, State} | {ok, State, Timeout} | + <name>Module:init(Args) -> {ok, State} | {ok, State, timeout()} | {stop, Reason}</name> - <fsummary> Makes necessary initializations and returns the + <fsummary>Makes necessary initializations and returns the initial channel state if the initializations succeed.</fsummary> <type> - <v> Args = term() </v> - <d> Last argument to ssh_channel:start_link/4.</d> - <v> State = term() </v> - <v>Timeout = timeout() </v> - <v> Reason = term() </v> + <v>Args = term()</v> + <d>Last argument to <c>ssh_channel:start_link/4</c>.</d> + <v>State = term()</v> + <v>Reason = term()</v> </type> <desc> - <p> Makes necessary initializations and returns the initial channel + <p>Makes necessary initializations and returns the initial channel state if the initializations succeed. </p> - <p>For more detailed information on timeouts see the section - <seealso marker="#cb_timeouts">CALLBACK TIMEOUTS</seealso>. </p> + <p>For more detailed information on time-outs, see Section + <seealso marker="#cb_timeouts">CALLBACK TIME-OUTS</seealso>. </p> </desc> </func> <func> - <name>CallbackModule:handle_call(Msg, From, State) -> Result</name> - <fsummary> Handles messages sent by calling - <c>ssh_channel:call/[2,3]</c></fsummary> + <name>Module:handle_call(Msg, From, State) -> Result</name> + <fsummary>Handles messages sent by calling + <c>ssh_channel:call/[2,3]</c>.</fsummary> <type> <v>Msg = term()</v> - <v>From = opaque to the user should be used as argument to - ssh_channel:reply/2</v> + <v>From = opaque()</v> + <d>Is to be used as argument to + <seealso marker="#reply-2">ssh_channel:reply/2</seealso></d> <v>State = term()</v> - <v>Result = {reply, Reply, NewState} | {reply, Reply, NewState, Timeout} - | {noreply, NewState} | {noreply , NewState, Timeout} + <v>Result = {reply, Reply, NewState} | {reply, Reply, NewState, timeout()} + | {noreply, NewState} | {noreply , NewState, timeout()} | {stop, Reason, Reply, NewState} | {stop, Reason, NewState} </v> - <v>Reply = term() - will be the return value of ssh_channel:call/[2,3]</v> - <v>Timeout = timeout() </v> - <v>NewState = term() - a possible updated version of State</v> + <v>Reply = term()</v> + <d>Will be the return value of <seealso marker="#call-2">ssh_channel:call/[2,3]</seealso></d> + <v>NewState = term()</v> <v>Reason = term()</v> </type> <desc> <p>Handles messages sent by calling - <c>ssh_channel:call/[2,3]</c> + <seealso marker="#call-2">ssh_channel:call/[2,3]</seealso> </p> - <p>For more detailed information on timeouts see the section - <seealso marker="#cb_timeouts">CALLBACK TIMEOUTS</seealso>. </p> + <p>For more detailed information on time-outs,, see Section + <seealso marker="#cb_timeouts">CALLBACK TIME-OUTS</seealso>.</p> </desc> </func> <func> - <name>CallbackModule:handle_cast(Msg, State) -> Result</name> - <fsummary> Handles messages sent by calling - <c>ssh_channel:cact/2</c></fsummary> + <name>Module:handle_cast(Msg, State) -> Result</name> + <fsummary>Handles messages sent by calling + <c>ssh_channel:cact/2</c>.</fsummary> <type> <v>Msg = term()</v> <v>State = term()</v> - <v>Result = {noreply, NewState} | {noreply, NewState, Timeout} + <v>Result = {noreply, NewState} | {noreply, NewState, timeout()} | {stop, Reason, NewState}</v> - <v>NewState = term() - a possible updated version of State</v> - <v>Timeout = timeout() </v> + <v>NewState = term() </v> <v>Reason = term()</v> </type> <desc> - <p> Handles messages sent by calling - <c>ssh_channel:cast/2</c> + <p>Handles messages sent by calling + <c>ssh_channel:cast/2</c>. </p> - <p>For more detailed information on timeouts see the section - <seealso marker="#cb_timeouts">CALLBACK TIMEOUTS</seealso>. </p> - <marker id="handle_msg"></marker> + <p>For more detailed information on time-outs, see Section + <seealso marker="#cb_timeouts">CALLBACK TIME-OUTS</seealso>.</p> </desc> </func> <func> - <name>CallbackModule:handle_msg(Msg, State) -> {ok, State} | + <name>Module:handle_msg(Msg, State) -> {ok, State} | {stop, ChannelId, State}</name> - <fsummary> Handle other messages than ssh connection protocol, - call or cast messages sent to the channel.</fsummary> + <fsummary>Handles other messages than SSH connection protocol, + call, or cast messages sent to the channel.</fsummary> <type> <v>Msg = timeout | term()</v> + <v>ChannelId = ssh_channel_id()</v> <v>State = term() </v> </type> <desc> - <p>Handle other messages than ssh connection protocol, call or + <p>Handles other messages than SSH Connection Protocol, call, or cast messages sent to the channel. </p> - <p> Possible erlang 'EXIT'-messages should be handled by this - function and all channels should handle the following message.</p> + <p>Possible Erlang 'EXIT' messages is to be handled by this + function and all channels are to handle the following message.</p> <taglist> <tag><c><![CDATA[{ssh_channel_up, ssh_channel_id(), ssh_connection_ref()}]]></c></tag> - <item>This is the first messages that will be received - by the channel, it is sent just before - the ssh_channel:init/1 function returns successfully. - This is especially useful if the server wants - to send a message to the client without first receiving - a message from the client. If the message is not useful - for your particular problem just ignore it by immediately - returning {ok, State}. - </item> + <item><p>This is the first message that the channel receives. + It is sent just before the <seealso + marker="#init-1">ssh_channel:init/1</seealso> function + returns successfully. This is especially useful if the + server wants to send a message to the client without first + receiving a message from it. If the message is not + useful for your particular scenario, ignore it by + immediately returning <c>{ok, State}</c>. + </p></item> </taglist> </desc> </func> <func> - <name>CallbackModule:handle_ssh_msg(Msg, State) -> {ok, State} | {stop, - ssh_channel_id(), State}</name> - <fsummary> Handles ssh connection protocol messages. </fsummary> + <name>Module:handle_ssh_msg(Msg, State) -> {ok, State} | {stop, + ChannelId, State}</name> + <fsummary>Handles <c>ssh</c> connection protocol messages.</fsummary> <type> - <v>Msg = {ssh_cm, ssh_connection_ref(), SshMsg}</v> - <v> SshMsg = tuple() - see message list below</v> + <v>Msg = ssh_connection:event()</v> + <v>ChannelId = ssh_channel_id()</v> <v>State = term()</v> </type> <desc> - <p> Handles ssh connection protocol messages that may need - service specific attention. + <p>Handles SSH Connection Protocol messages that may need + service-specific attention. For details, + see <seealso marker="ssh_connection"> ssh_connection:event()</seealso>. </p> - - <p> All channels should handle the following messages. For - channels implementing subsystems the handle_ssh_msg-callback - will not be called for any other messages. </p> - - <taglist> - <tag><c><![CDATA[{ssh_cm, ssh_connection_ref(), {data, ssh_channel_id(), - ssh_data_type_code(), binary() = Data}}]]></c></tag> - <item> Data has arrived on the channel. When the callback - for this message returns the channel behavior will adjust - the ssh flow control window.</item> - - <tag><c><![CDATA[{ssh_cm, ssh_connection_ref(), {eof, - ssh_channel_id()}}]]></c></tag> - <item>Indicteas that the other side will not send any more - data.</item> - - <tag><c><![CDATA[{ssh_cm, ssh_connection_ref(), {signal, - ssh_channel_id(), ssh_signal()}} ]]></c></tag> - <item>A signal can be delivered to the remote - process/service using the following message. Some systems - may not implement signals, in which case they should ignore - this message.</item> - - <tag><c><![CDATA[{ssh_cm, ssh_connection_ref(), - {exit_signal, ssh_channel_id(), string() = exit_signal, - string() = ErrorMsg, string() = - LanguageString}}]]></c></tag> - <item>A remote execution may terminate violently due to a - signal then this message may be received. For details on valid string - values see RFC 4254 section 6.10</item> - - <tag><c><![CDATA[{ssh_cm, ssh_connection_ref(), {exit_status, - ssh_channel_id(), integer() = ExitStatus}}]]></c></tag> - <item> When the command running at the other end terminates, - the following message can be sent to return the exit status - of the command. A zero 'exit_status' usually means that the - command terminated successfully.</item> - </taglist> - - <p> Channels implementing a shell and command execution on the server side - should also handle the following messages. </p> - - <taglist> - <tag><c><![CDATA[{ssh_cm, ssh_connection_ref(), {env, ssh_channel_id(), - boolean() = WantReply, string() = Var, string() = Value}}]]></c></tag> - <item> Environment variables may be passed to the - shell/command to be started later. Note that before the - callback returns it should call the function - ssh_connection:reply_request/4 with the boolean value of <c> - WantReply</c> as the second argument. - </item> - - <tag><c><![CDATA[{ssh_cm, ConnectionRef, {exec, ssh_channel_id(), - boolean() = WantReply, string() = Cmd}}]]></c></tag> - <item> This message will request that the server start the - execution of the given command. Note that before the - callback returns it should call the function - ssh_connection:reply_request/4 with the boolean value of <c> - WantReply</c> as the second argument.</item> - - <tag><c><![CDATA[{ssh_cm, ssh_connection_ref(), {pty, ssh_channel_id(), - boolean() = WantReply, {string() = Terminal, integer() = CharWidth, - integer() = RowHeight, integer() = PixelWidth, integer() = PixelHight, - [{atom() | integer() = Opcode, - integer() = Value}] = TerminalModes}}}]]></c></tag> - <item>A pseudo-terminal has been requested for the - session. Terminal is the value of the TERM environment - variable value (e.g., vt100). Zero dimension parameters must - be ignored. The character/row dimensions override the pixel - dimensions (when nonzero). Pixel dimensions refer to the - drawable area of the window. The <c>Opcode</c> in the - <c>TerminalModes</c> list is the mnemonic name, represented - as an lowercase erlang atom, defined in RFC 4254 section 8, - or the opcode if the mnemonic name is not listed in the - RFC. Example <c>OP code: 53, mnemonic name ECHO erlang atom: - echo</c>. Note that before the callback returns it should - call the function ssh_connection:reply_request/4 with the - boolean value of <c> WantReply</c> as the second - argument.</item> - - <tag><c><![CDATA[{ssh_cm, ConnectionRef, {shell, boolean() = - WantReply}}]]></c></tag> - <item> This message will request that the user's default - shell be started at the other end. Note that before the - callback returns it should call the function - ssh_connection:reply_request/4 with the value of <c> - WantReply</c> as the second argument. - </item> - - <tag><c><![CDATA[ {ssh_cm, ssh_connection_ref(), {window_change, - ssh_channel_id(), integer() = CharWidth, integer() = RowHeight, - integer() = PixWidth, integer() = PixHeight}}]]></c></tag> - <item> When the window (terminal) size changes on the client - side, it MAY send a message to the other side to inform it - of the new dimensions.</item> - </taglist> - <p> The following message is completely taken care of by the - ssh channel behavior</p> + <p>The following message is taken care of by the + <c>ssh_channel</c> behavior.</p> <taglist> - <tag><c><![CDATA[{ssh_cm, ssh_connection_ref(), {closed, - ssh_channel_id()}}]]></c></tag> - <item> The channel behavior will send a close message to the - other side if such a message has not already been sent and - then terminate the channel with reason normal.</item> + <tag><c><![CDATA[{closed, ssh_channel_id()}]]></c></tag> + <item><p>The channel behavior sends a close message to the + other side, if such a message has not already been sent. + Then it terminates the channel with reason <c>normal</c>.</p></item> </taglist> </desc> </func> <func> - <name>CallbackModule:terminate(Reason, State) -> _</name> - <fsummary> </fsummary> + <name>Module:terminate(Reason, State) -> _</name> + <fsummary>Does cleaning up before channel process termination. + </fsummary> <type> <v>Reason = term()</v> <v>State = term()</v> </type> <desc> <p>This function is called by a channel process when it is - about to terminate. Before this function is called ssh_connection:close/2 - will be called if it has not been called earlier. - This function should be the opposite of <c>CallbackModule:init/1</c> - and do any necessary cleaning up. When it returns, the - channel process terminates with reason <c>Reason</c>. The return value is - ignored. + about to terminate. Before this function is called, <seealso + marker="ssh_connection#close-2"> ssh_connection:close/2 + </seealso> is called, if it has not been called earlier. + This function does any necessary cleaning + up. When it returns, the channel process terminates with + reason <c>Reason</c>. The return value is ignored. </p> </desc> </func> diff --git a/lib/ssh/doc/src/ssh_client_key_api.xml b/lib/ssh/doc/src/ssh_client_key_api.xml new file mode 100644 index 0000000000..a1cd9d4b02 --- /dev/null +++ b/lib/ssh/doc/src/ssh_client_key_api.xml @@ -0,0 +1,138 @@ +<?xml version="1.0" encoding="utf-8" ?> +<!DOCTYPE erlref SYSTEM "erlref.dtd"> + +<erlref> + <header> + <copyright> + <year>2012</year> + <year>2016</year> + <holder>Ericsson AB, All Rights Reserved</holder> + </copyright> + <legalnotice> + Licensed under the Apache License, Version 2.0 (the "License"); + you may not use this file except in compliance with the License. + You may obtain a copy of the License at + + http://www.apache.org/licenses/LICENSE-2.0 + + Unless required by applicable law or agreed to in writing, software + distributed under the License is distributed on an "AS IS" BASIS, + WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + See the License for the specific language governing permissions and + limitations under the License. + + The Initial Developer of the Original Code is Ericsson AB. + </legalnotice> + <title>ssh_client_key_api</title> + <prepared></prepared> + <docno></docno> + <date></date> + <rev></rev> + </header> + <module>ssh_client_key_api</module> + <modulesummary> + -behaviour(ssh_client_key_api). + </modulesummary> + <description> + <p>Behavior describing the API for public key handling of an SSH client. By implementing + the callbacks defined in this behavior, the public key handling of an SSH client can + be customized. By default the <c>ssh</c> application implements this behavior + with help of the standard OpenSSH files, + see the <seealso marker="SSH_app"> ssh(6)</seealso> application manual.</p> + </description> + + <section> + <title>DATA TYPES</title> + + <p>Type definitions that are used more than once in this module, + or abstractions to indicate the intended use of the data + type, or both. For more details on public key data types, + refer to Section 2 Public Key Records in the + <seealso marker="public_key:public_key_records"> public_key user's guide:</seealso> + </p> + <taglist> + <tag><c>boolean() =</c></tag> + <item><p><c>true | false</c></p></item> + <tag><c>string() =</c></tag> + <item><p><c>[byte()]</c></p></item> + <tag><c>public_key() =</c></tag> + <item><p><c>#'RSAPublicKey'{}| {integer(), #'Dss-Parms'{}}| term()</c></p></item> + <tag><c>private_key() =</c></tag> + <item><p><c>#'RSAPrivateKey'{} | #'DSAPrivateKey'{} | term()</c></p></item> + <tag><c>public_key_algorithm() =</c></tag> + <item><p><c>'ssh-rsa'| 'ssh-dss' | atom()</c></p></item> + </taglist> + </section> + + <funcs> + <func> + <name>Module:add_host_key(HostNames, Key, ConnectOptions) -> ok | {error, Reason}</name> + <fsummary>Adds a host key to the set of trusted host keys.</fsummary> + <type> + <v>HostNames = string()</v> + <d>Description of the host that owns the <c>PublicKey</c>.</d> + + <v>Key = public_key()</v> + <d>Normally an RSA or DSA public key, but handling of other public keys can be added.</d> + + <v>ConnectOptions = proplists:proplist()</v> + <d>Options provided to <seealso marker="ssh#connect-3">ssh:connect/[3,4]</seealso></d> + <v>Reason = term().</v> + </type> + <desc> + <p>Adds a host key to the set of trusted host keys.</p> + </desc> + </func> + + <func> + <name>Module:is_host_key(Key, Host, Algorithm, ConnectOptions) -> Result</name> + <fsummary>Checks if a host key is trusted.</fsummary> + <type> + <v>Key = public_key() </v> + <d>Normally an RSA or DSA public key, but handling of other public keys can be added.</d> + + <v>Host = string()</v> + <d>Description of the host.</d> + + <v>Algorithm = public_key_algorithm()</v> + <d>Host key algorithm. Is to support <c>'ssh-rsa'| 'ssh-dss'</c>, but more algorithms + can be handled.</d> + + <v>ConnectOptions = proplists:proplist() </v> + <d>Options provided to <seealso marker="ssh#connect-3">ssh:connect/[3,4]</seealso>.</d> + + <v>Result = boolean()</v> + </type> + <desc> + <p>Checks if a host key is trusted.</p> + </desc> + </func> + + <func> + <name>Module:user_key(Algorithm, ConnectOptions) -> + {ok, PrivateKey} | {error, Reason}</name> + <fsummary>Fetches the users <em>public key</em> matching the <c>Algorithm</c>.</fsummary> + <type> + <v>Algorithm = public_key_algorithm()</v> + <d>Host key algorithm. Is to support <c>'ssh-rsa'| 'ssh-dss'</c> but more algorithms + can be handled.</d> + + <v>ConnectOptions = proplists:proplist()</v> + <d>Options provided to <seealso marker="ssh#connect-3">ssh:connect/[3,4]</seealso></d> + + <v>PrivateKey = private_key()</v> + <d>Private key of the user matching the <c>Algorithm</c>.</d> + + <v>Reason = term()</v> + </type> + + <desc> + <p>Fetches the users <em>public key</em> matching the <c>Algorithm</c>.</p> + <note><p>The private key contains the public key.</p></note> + + </desc> + </func> + + </funcs> + +</erlref> diff --git a/lib/ssh/doc/src/ssh_connection.xml b/lib/ssh/doc/src/ssh_connection.xml index 9942306b93..150d46a9a2 100644 --- a/lib/ssh/doc/src/ssh_connection.xml +++ b/lib/ssh/doc/src/ssh_connection.xml @@ -1,193 +1,358 @@ -<?xml version="1.0" encoding="latin1" ?> +<?xml version="1.0" encoding="utf-8" ?> <!DOCTYPE erlref SYSTEM "erlref.dtd"> <erlref> <header> <copyright> <year>2008</year> - <year>2011</year> + <year>2015</year> <holder>Ericsson AB, All Rights Reserved</holder> </copyright> <legalnotice> - The contents of this file are subject to the Erlang Public License, - Version 1.1, (the "License"); you may not use this file except in - compliance with the License. You should have received a copy of the - Erlang Public License along with this software. If not, it can be - retrieved online at http://www.erlang.org/. + Licensed under the Apache License, Version 2.0 (the "License"); + you may not use this file except in compliance with the License. + You may obtain a copy of the License at + + http://www.apache.org/licenses/LICENSE-2.0 - Software distributed under the License is distributed on an "AS IS" - basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See - the License for the specific language governing rights and limitations - under the License. + Unless required by applicable law or agreed to in writing, software + distributed under the License is distributed on an "AS IS" BASIS, + WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + See the License for the specific language governing permissions and + limitations under the License. The Initial Developer of the Original Code is Ericsson AB. </legalnotice> <title>ssh_connection</title> - <prepared>Ingela Anderton Andin</prepared> - <responsible></responsible> + <prepared></prepared> <docno></docno> - <approved></approved> - <checked></checked> <date></date> <rev></rev> </header> <module>ssh_connection</module> - <modulesummary>This module provides an API to the ssh connection protocol. + <modulesummary> + This module provides API functions to send SSH Connection Protocol + events to the other side of an SSH channel. </modulesummary> + <description> - <p>This module provides an API to the ssh connection protocol. - Not all features of the connection protocol are officially supported yet. - Only the ones supported are documented here.</p> + <p>The <url href="http://www.ietf.org/rfc/rfc4254.txt">SSH Connection Protocol</url> + is used by clients and servers, that is, SSH channels, to communicate over the + SSH connection. The API functions in this module send SSH Connection Protocol events, + which are received as messages by the remote channel. + If the receiving channel is an Erlang process, the + messages have the format + <c><![CDATA[{ssh_cm, ssh_connection_ref(), ssh_event_msg()}]]></c>. + If the <seealso marker="ssh_channel">ssh_channel</seealso> behavior is used to + implement the channel process, these messages are handled by + <seealso marker="ssh_channel#Module:handle_ssh_msg-2">handle_ssh_msg/2</seealso>.</p> </description> - <section> - <title>COMMON DATA TYPES </title> - <p>Type definitions that are used more than once in this module and/or - abstractions to indicate the intended use of the data type:</p> - - <p><c>boolean() = true | false </c></p> - <p><c>string() = list of ASCII characters</c></p> - <p><c>timeout() = infinity | integer() - in milliseconds.</c></p> - <p><c>ssh_connection_ref() - opaque to the user returned by - ssh:connect/3 or sent to a ssh channel processes</c></p> - <p><c>ssh_channel_id() = integer() </c></p> - <p><c>ssh_data_type_code() = 1 ("stderr") | 0 ("normal") are - currently valid values see RFC 4254 section 5.2.</c></p> - <p><c>ssh_request_status() = success | failure</c></p> - </section> - - <section> - <title>MESSAGES SENT TO CHANNEL PROCESSES</title> + <section> + <title>DATA TYPES</title> + + <p>Type definitions that are used more than once in this module, + or abstractions to indicate the intended use of the data + type, or both:</p> + + <taglist> + <tag><c>boolean() =</c></tag> + <item><p><c>true | false </c></p></item> + <tag><c>string() =</c></tag> + <item><p>list of ASCII characters</p></item> + <tag><c>timeout() =</c></tag> + <item><p><c>infinity | integer()</c> in milliseconds</p></item> + <tag><c>ssh_connection_ref() =</c></tag> + <item><p>opaque() -as returned by + <c>ssh:connect/3</c> or sent to an SSH channel processes</p></item> + <tag><c>ssh_channel_id() =</c></tag> + <item><p><c>integer()</c></p></item> + <tag><c>ssh_data_type_code() =</c></tag> + <item><p><c>1</c> ("stderr") | <c>0</c> ("normal") are + valid values, see + <url href="http://www.ietf.org/rfc/rfc4254.txt">RFC 4254</url> Section 5.2.</p></item> + <tag><c>ssh_request_status() =</c></tag> + <item><p> <c>success | failure</c></p></item> + <tag><c>event() =</c></tag> + <item><p><c>{ssh_cm, ssh_connection_ref(), ssh_event_msg()}</c></p></item> + <tag><c>ssh_event_msg() =</c></tag> + <item><p><c>data_events() | status_events() | terminal_events()</c></p></item> + <tag><c>reason() =</c></tag> + <item><p><c>timeout | closed</c></p></item> + </taglist> + + <taglist> + <tag><em>data_events()</em></tag> + <item> + <taglist> + <tag><c><![CDATA[{data, ssh_channel_id(), ssh_data_type_code(), Data :: binary()}]]></c></tag> + <item><p>Data has arrived on the channel. This event is sent as a + result of calling <seealso marker="ssh_connection#send-3"> + ssh_connection:send/[3,4,5]</seealso>.</p></item> + + <tag><c><![CDATA[{eof, ssh_channel_id()}]]></c></tag> + <item><p>Indicates that the other side sends no more data. + This event is sent as a result of calling <seealso + marker="ssh_connection#send_eof-2"> ssh_connection:send_eof/2</seealso>. + </p></item> + </taglist> + </item> + + <tag><em>status_events()</em></tag> + <item> + + <taglist> + <tag><c><![CDATA[{signal, ssh_channel_id(), ssh_signal()}]]></c></tag> + <item><p>A signal can be delivered to the remote process/service + using the following message. Some systems do not support + signals, in which case they are to ignore this message. There is + currently no function to generate this event as the signals + referred to are on OS-level and not something generated by an + Erlang program.</p></item> + + <tag><c><![CDATA[{exit_signal, ssh_channel_id(), ExitSignal :: string(), ErrorMsg ::string(), + LanguageString :: string()}]]></c></tag> + + <item><p>A remote execution can terminate violently because of a signal. + Then this message can be received. For details on valid string + values, see <url href="http://www.ietf.org/rfc/rfc4254.txt">RFC 4254</url> + Section 6.10, which shows a special case of these signals.</p></item> + + <tag><c><![CDATA[{exit_status, ssh_channel_id(), ExitStatus :: integer()}]]></c></tag> + <item><p>When the command running at the other end terminates, the + following message can be sent to return the exit status of the + command. A zero <c>exit_status</c> usually means that the command + terminated successfully. This event is sent as a result of calling + <seealso marker="ssh_connection#exit_status-3"> + ssh_connection:exit_status/3</seealso>.</p></item> + + <tag><c><![CDATA[{closed, ssh_channel_id()}]]></c></tag> + <item><p>This event is sent as a result of calling + <seealso marker="ssh_connection#close-2">ssh_connection:close/2</seealso>. + Both the handling of this event and sending it are taken care of by the + <seealso marker="ssh_channel">ssh_channel</seealso> behavior.</p></item> + + </taglist> + </item> + + <tag><em>terminal_events()</em></tag> + + <item> + <p>Channels implementing a shell and command execution on the + server side are to handle the following messages that can be sent by client- + channel processes.</p> + + <p>Events that include a <c>WantReply</c> expect the event handling + process to call <seealso marker="ssh_connection#reply_request-4"> + ssh_connection:reply_request/4</seealso> + with the boolean value of <c>WantReply</c> as the second argument.</p> + + <taglist> + <tag><c><![CDATA[{env, ssh_channel_id(), WantReply :: boolean(), + Var ::string(), Value :: string()}]]></c></tag> + <item><p>Environment variables can be passed to the shell/command + to be started later. This event is sent as a result of calling <seealso + marker="ssh_connection#setenv-5"> ssh_connection:setenv/5</seealso>. + </p></item> + + <tag><c><![CDATA[{pty, ssh_channel_id(), + WantReply :: boolean(), {Terminal :: string(), CharWidth :: integer(), + RowHeight :: integer(), PixelWidth :: integer(), PixelHeight :: integer(), + TerminalModes :: [{Opcode :: atom() | integer(), + Value :: integer()}]}}]]></c></tag> + <item><p>A pseudo-terminal has been requested for the + session. <c>Terminal</c> is the value of the TERM environment + variable value, that is, <c>vt100</c>. Zero dimension parameters must + be ignored. The character/row dimensions override the pixel + dimensions (when non-zero). Pixel dimensions refer to the + drawable area of the window. <c>Opcode</c> in the + <c>TerminalModes</c> list is the mnemonic name, represented + as a lowercase Erlang atom, defined in + <url href="http://www.ietf.org/rfc/rfc4254.txt">RFC 4254</url>, Section 8. + It can also be an <c>Opcode</c> if the mnemonic name is not listed in the + RFC. Example: <c>OP code: 53, mnemonic name ECHO erlang atom: + echo</c>. This event is sent as a result of calling <seealso + marker="ssh_connection#ptty_alloc/4">ssh_connection:ptty_alloc/4</seealso>.</p></item> + + <tag><c><![CDATA[{shell, WantReply :: boolean()}]]></c></tag> + <item><p>This message requests that the user default shell + is started at the other end. This event is sent as a result of calling + <seealso marker="ssh_connection#shell-2"> ssh_connection:shell/2</seealso>. + </p></item> + + <tag><c><![CDATA[{window_change, ssh_channel_id(), CharWidth() :: integer(), + RowHeight :: integer(), PixWidth :: integer(), PixHeight :: integer()}]]></c></tag> + <item><p>When the window (terminal) size changes on the client + side, it <em>can</em> send a message to the server side to inform it of + the new dimensions. No API function generates this event.</p></item> - <p>As a result of the ssh connection protocol messages on the form - <c><![CDATA[{ssh_cm, ssh_connection_ref(), term()}]]></c> - will be sent to a channel process. The term will contain - information regarding the ssh connection protocol event, - for details see the ssh channel behavior callback <seealso - marker="ssh_channel">handle_ssh_msg/2 </seealso> </p> - </section> - - <funcs> + <tag><c><![CDATA[{exec, ssh_channel_id(), + WantReply :: boolean(), Cmd :: string()}]]></c></tag> + <item><p>This message requests that the server starts + execution of the given command. This event is sent as a result of calling <seealso + marker="ssh_connection#exec-4">ssh_connection:exec/4 </seealso>. + </p></item> + </taglist> + </item> + </taglist> + </section> + + <funcs> <func> <name>adjust_window(ConnectionRef, ChannelId, NumOfBytes) -> ok</name> - <fsummary>Adjusts the ssh flowcontrol window. </fsummary> + <fsummary>Adjusts the SSH flow control window.</fsummary> <type> - <v> ConnectionRef = ssh_connection_ref() </v> - <v> ChannelId = ssh_channel_id() </v> - <v> NumOfBytes = integer()</v> + <v>ConnectionRef = ssh_connection_ref()</v> + <v>ChannelId = ssh_channel_id()</v> + <v>NumOfBytes = integer()</v> </type> <desc> - <p>Adjusts the ssh flowcontrol window. </p> + <p>Adjusts the SSH flow control window. This is to be done by both the + client- and server-side channel processes.</p> - <note><p>This will be taken care of by the ssh_channel - behavior when the callback <seealso marker="ssh_channel"> - handle_ssh_msg/2 </seealso> has returned after processing a - {ssh_cm, ssh_connection_ref(), {data, ssh_channel_id(), - ssh_data_type_code(), binary()}} - message, and should normally not be called explicitly.</p></note> + <note><p>Channels implemented with the <seealso marker="ssh_channel"> ssh_channel</seealso> + behavior do not normally need to call this function as flow control + is handled by the behavior. The behavior adjusts the window every time + the callback <seealso marker="ssh_channel#Module:handle_ssh_msg-2"> + handle_ssh_msg/2</seealso> returns after processing channel data.</p></note> </desc> </func> <func> <name>close(ConnectionRef, ChannelId) -> ok</name> - <fsummary>Sends a close message on the channel <c>ChannelId</c>. </fsummary> + <fsummary>Sends a close message on the channel <c>ChannelId</c>.</fsummary> <type> - <v> ConnectionRef = ssh_connection_ref() </v> - <v> ChannelId = ssh_channel_id()</v> + <v>ConnectionRef = ssh_connection_ref()</v> + <v>ChannelId = ssh_channel_id()</v> </type> <desc> - <p>Sends a close message on the channel <c>ChannelId</c> + <p>A server- or client-channel process can choose to close their session by + sending a close event. </p> - <note><p>This function will be called by the ssh channel - behavior when the channel is terminated see <seealso - marker="ssh_channel"> ssh_channel(3) </seealso> and should - normally not be called explicitly.</p></note> + <note><p>This function is called by the <c>ssh_channel</c> + behavior when the channel is terminated, see <seealso + marker="ssh_channel"> ssh_channel(3)</seealso>. Thus, channels implemented + with the behavior are not to call this function explicitly.</p></note> </desc> </func> <func> - <name>exec(ConnectionRef, ChannelId, Command, TimeOut) -> ssh_request_status() </name> - <fsummary>Will request that the server start the - execution of the given command. </fsummary> + <name>exec(ConnectionRef, ChannelId, Command, TimeOut) -> ssh_request_status() | + {error, reason()}</name> + <fsummary>Requests that the server starts the execution of the given command.</fsummary> <type> - <v> ConnectionRef = ssh_connection_ref() </v> - <v> ChannelId = ssh_channel_id()</v> - <v> Command = string()</v> - <v>Timeout = timeout() </v> + <v>ConnectionRef = ssh_connection_ref()</v> + <v>ChannelId = ssh_channel_id()</v> + <v>Command = string()</v> + <v>Timeout = timeout()</v> </type> <desc> - <p>Will request that the server start the execution of the - given command, the result will be received as:</p> + <p>Is to be called by a client-channel process to request that the server starts + executing the given command. The result is several messages according to the + following pattern. The last message is a channel close message, as the <c>exec</c> + request is a one-time execution that closes the channel when it is done.</p> <taglist> - <tag><c> N X {ssh_cm, - ssh_connection_ref(), {data, ssh_channel_id(), ssh_data_type_code(), - binary() = Data}} </c></tag> - <item>The result of executing the command may be only one line - or thousands of lines depending on the command.</item> + <tag><c>N x {ssh_cm, ssh_connection_ref(), + {data, ssh_channel_id(), ssh_data_type_code(), Data :: binary()}}</c></tag> + <item><p>The result of executing the command can be only one line + or thousands of lines depending on the command.</p></item> - <tag><c> 1 X {ssh_cm, ssh_connection_ref(), {eof, ssh_channel_id()}}</c></tag> - <item>Indicates that no more data will be sent.</item> + <tag><c>0 or 1 x {ssh_cm, ssh_connection_ref(), {eof, ssh_channel_id()}}</c></tag> + <item><p>Indicates that no more data is to be sent.</p></item> - <tag><c>0 or 1 X {ssh_cm, + <tag><c>0 or 1 x {ssh_cm, ssh_connection_ref(), {exit_signal, - ssh_channel_id(), string() = ExitSignal, string() = ErrorMsg, string() = LanguageString}}</c></tag> - <item>Not all systems send signals. For details on valid string - values see RFC 4254 section 6.10 </item> + ssh_channel_id(), ExitSignal :: string(), ErrorMsg :: string(), LanguageString :: string()}}</c></tag> + <item><p>Not all systems send signals. For details on valid string + values, see RFC 4254, Section 6.10</p></item> - <tag><c>0 or 1 X {ssh_cm, ssh_connection_ref(), {exit_status, - ssh_channel_id(), integer() = ExitStatus}}</c></tag> - <item>It is recommended by the <c>ssh connection protocol</c> that this - message shall be sent, but that may not always be the case.</item> + <tag><c>0 or 1 x {ssh_cm, ssh_connection_ref(), {exit_status, + ssh_channel_id(), ExitStatus :: integer()}}</c></tag> + <item><p>It is recommended by the SSH Connection Protocol to send this + message, but that is not always the case.</p></item> - <tag><c> 1 X {ssh_cm, ssh_connection_ref(), + <tag><c>1 x {ssh_cm, ssh_connection_ref(), {closed, ssh_channel_id()}}</c></tag> - <item>Indicates that the ssh channel started for the - execution of the command has now been shutdown.</item> + <item><p>Indicates that the <c>ssh_channel</c> started for the + execution of the command has now been shut down.</p></item> </taglist> - - <p> These message should be handled by the - client. The <seealso marker="ssh_channel">ssh channel - behavior</seealso> can be used when writing a client. - </p> </desc> </func> - <func> <name>exit_status(ConnectionRef, ChannelId, Status) -> ok</name> <fsummary>Sends the exit status of a command to the client.</fsummary> <type> - <v> ConnectionRef = ssh_connection_ref() </v> - <v> ChannelId = ssh_channel_id()</v> - <v> Status = integer()</v> + <v>ConnectionRef = ssh_connection_ref() </v> + <v>ChannelId = ssh_channel_id()</v> + <v>Status = integer()</v> </type> <desc> - <p>Sends the exit status of a command to the client.</p> + <p>Is to be called by a server-channel process to send the exit status of a command + to the client.</p> </desc> - </func> + </func> + <func> + <name>ptty_alloc(ConnectionRef, ChannelId, Options) -></name> + <name>ptty_alloc(ConnectionRef, ChannelId, Options, Timeout) -> > ssh_request_status() | + {error, reason()}</name> + <fsummary>Sends an SSH Connection Protocol <c>pty_req</c>, + to allocate a pseudo-terminal.</fsummary> + <type> + <v>ConnectionRef = ssh_connection_ref()</v> + <v>ChannelId = ssh_channel_id()</v> + <v>Options = proplists:proplist()</v> + </type> + <desc> + <p>Sends an SSH Connection Protocol <c>pty_req</c>, to allocate a pseudo-terminal. + Is to be called by an SSH client process.</p> + <p>Options:</p> + + <taglist> + <tag>{term, string()}</tag> + <item><p>Defaults to <em>os:getenv("TERM")</em> or <em>vt100</em> + if it is undefined.</p></item> + + <tag>{width, integer()}</tag> + <item><p>Defaults to 80 if <c>pixel_width</c> is not defined.</p></item> + + <tag>{height, integer()}</tag> + <item><p>Defaults to 24 if <c>pixel_height</c> is not defined.</p></item> + + <tag>{pixel_width, integer()}</tag> + <item><p>Is disregarded if <c>width</c> is defined.</p></item> + + <tag>{pixel_height, integer()}</tag> + <item><p>Is disregarded if <c>height</c> is defined.</p></item> + + <tag>{pty_opts, [{posix_atom(), integer()}]}</tag> + <item><p>Option can be an empty list. Otherwise, see possible <em>POSIX</em> names + in Section 8 in <url href="http://www.ietf.org/rfc/rfc4254.txt"> RFC 4254</url>.</p> + </item> + </taglist> + </desc> + </func> + <func> - <name>reply_request(ConnectionRef, WantReply, Status, CannelId) -> ok</name> - <fsummary>Send status replies to requests that want such replies. </fsummary> + <name>reply_request(ConnectionRef, WantReply, Status, ChannelId) -> ok</name> + <fsummary>Sends status replies to requests that want such replies.</fsummary> <type> - <v> ConnectionRef = ssh_connection_ref() </v> - <v> WantReply = boolean()</v> - <v> Status = ssh_request_status() </v> - <v> ChannelId = ssh_channel_id()</v> + <v>ConnectionRef = ssh_connection_ref()</v> + <v>WantReply = boolean()</v> + <v>Status = ssh_request_status()</v> + <v>ChannelId = ssh_channel_id()</v> </type> <desc> <p>Sends status replies to requests where the requester has - stated that they want a status report e.i .<c> WantReply = true</c>, - if <c> WantReply</c> is false calling this function will be a - "noop". Should be called after handling an ssh connection - protocol message containing a <c>WantReply</c> boolean - value. See the ssh_channel behavior callback <seealso - marker="ssh_channel"> handle_ssh_msg/2 </seealso> - </p> + stated that it wants a status report, that is, <c>WantReply = true</c>. + If <c>WantReply</c> is <c>false</c>, calling this function becomes a + "noop". Is to be called while handling an SSH Connection + Protocol message containing a <c>WantReply</c> boolean value.</p> </desc> </func> @@ -196,103 +361,104 @@ <name>send(ConnectionRef, ChannelId, Data, Timeout) -></name> <name>send(ConnectionRef, ChannelId, Type, Data) -></name> <name>send(ConnectionRef, ChannelId, Type, Data, TimeOut) -> - ok | {error, timeout}</name> - <fsummary>Sends channel data </fsummary> + ok | {error, timeout} | {error, closed}</name> + <fsummary>Sends channel data.</fsummary> <type> - <v> ConnectionRef = ssh_connection_ref() </v> - <v> ChannelId = ssh_channel_id()</v> - <v> Data = binary()</v> - <v> Type = ssh_data_type_code()</v> - <v> Timeout = timeout()</v> + <v>ConnectionRef = ssh_connection_ref()</v> + <v>ChannelId = ssh_channel_id()</v> + <v>Data = binary()</v> + <v>Type = ssh_data_type_code()</v> + <v>Timeout = timeout()</v> </type> <desc> - <p>Sends channel data. + <p>Is to be called by client- and server-channel processes to send data to each other. + </p> + <p>The function <seealso marker="ssh:ssh_connection#subsystem/4">subsystem/4</seealso> and subsequent + calls of <c>send/3,4,5</c> must be executed in the same process. </p> </desc> </func> <func> - <name>send_eof(ConnectionRef, ChannelId) -> ok </name> - <fsummary>Sends eof on the channel <c>ChannelId</c>. </fsummary> + <name>send_eof(ConnectionRef, ChannelId) -> ok | {error, closed}</name> + <fsummary>Sends EOF on channel <c>ChannelId</c>.</fsummary> <type> - <v> ConnectionRef = ssh_connection_ref() </v> - <v> ChannelId = ssh_channel_id()</v> + <v>ConnectionRef = ssh_connection_ref()</v> + <v>ChannelId = ssh_channel_id()</v> </type> <desc> - <p>Sends eof on the channel <c>ChannelId</c>. - </p> + <p>Sends EOF on channel <c>ChannelId</c>.</p> </desc> </func> <func> - <name>session_channel(ConnectionRef, Timeout) -> </name> + <name>session_channel(ConnectionRef, Timeout) -></name> <name>session_channel(ConnectionRef, InitialWindowSize, - MaxPacketSize, Timeout) -> {ok, ssh_channel_id()} | {error, Reason}</name> - <fsummary>Opens a channel for a ssh session. A session is a - remote execution of a program. The program may be a shell, an - application, a system command, or some built-in subsystem. </fsummary> + MaxPacketSize, Timeout) -> {ok, ssh_channel_id()} | {error, reason()}</name> + <fsummary>Opens a channel for an SSH session.</fsummary> <type> - <v> ConnectionRef = ssh_connection_ref()</v> - <v> InitialWindowSize = integer() </v> - <v> MaxPacketSize = integer() </v> - <v> Timeout = timeout()</v> - <v> Reason = term() </v> + <v>ConnectionRef = ssh_connection_ref()</v> + <v>InitialWindowSize = integer()</v> + <v>MaxPacketSize = integer()</v> + <v>Timeout = timeout()</v> + <v>Reason = term()</v> </type> <desc> - <p>Opens a channel for a ssh session. A session is a - remote execution of a program. The program may be a shell, an - application, a system command, or some built-in subsystem. - </p> + <p>Opens a channel for an SSH session. The channel id returned from this function + is the id used as input to the other functions in this module.</p> </desc> </func> <func> - <name>setenv(ConnectionRef, ChannelId, Var, Value, TimeOut) -> ssh_request_status()</name> - <fsummary> Environment variables may be passed to the + <name>setenv(ConnectionRef, ChannelId, Var, Value, TimeOut) -> ssh_request_status() | + {error, reason()}</name> + <fsummary>Environment variables can be passed to the shell/command to be started later.</fsummary> <type> - <v> ConnectionRef = ssh_connection_ref() </v> - <v> ChannelId = ssh_channel_id()</v> - <v> Var = string()</v> - <v> Value = string()</v> - <v> Timeout = timeout()</v> + <v>ConnectionRef = ssh_connection_ref()</v> + <v>ChannelId = ssh_channel_id()</v> + <v>Var = string()</v> + <v>Value = string()</v> + <v>Timeout = timeout()</v> </type> <desc> - <p> Environment variables may be passed to the shell/command to be - started later. - </p> + <p>Environment variables can be passed before starting the + shell/command. Is to be called by a client channel processes.</p> </desc> </func> <func> - <name>shell(ConnectionRef, ChannelId) -> ssh_request_status() + <name>shell(ConnectionRef, ChannelId) -> ssh_request_status() | {error, closed} </name> - <fsummary> Will request that the user's default shell (typically - defined in /etc/passwd in UNIX systems) be started at the other - end. </fsummary> + <fsummary>Requests that the user default shell (typically defined in + /etc/passwd in Unix systems) is to be executed at the server end.</fsummary> <type> - <v> ConnectionRef = ssh_connection_ref() </v> - <v> ChannelId = ssh_channel_id()</v> + <v>ConnectionRef = ssh_connection_ref()</v> + <v>ChannelId = ssh_channel_id()</v> </type> <desc> - <p> Will request that the user's default shell (typically - defined in /etc/passwd in UNIX systems) be started at the - other end. - </p> + <p>Is to be called by a client channel process to request that the user default + shell (typically defined in /etc/passwd in Unix systems) is executed + at the server end.</p> </desc> </func> <func> - <name>subsystem(ConnectionRef, ChannelId, Subsystem, Timeout) -> ssh_request_status()</name> - <fsummary> </fsummary> + <name>subsystem(ConnectionRef, ChannelId, Subsystem, Timeout) -> ssh_request_status() | + {error, reason()}</name> + <fsummary>Requests to execute a predefined subsystem on the server.</fsummary> <type> - <v> ConnectionRef = ssh_connection_ref() </v> - <v> ChannelId = ssh_channel_id()</v> - <v> Subsystem = string()</v> - <v> Timeout = timeout()</v> + <v>ConnectionRef = ssh_connection_ref()</v> + <v>ChannelId = ssh_channel_id()</v> + <v>Subsystem = string()</v> + <v>Timeout = timeout()</v> </type> <desc> - <p> Sends a request to execute a predefined subsystem. + <p>Is to be called by a client-channel process for requesting to execute a predefined + subsystem on the server. + </p> + <p>The function <c>subsystem/4</c> and subsequent calls of + <seealso marker="ssh:ssh_connection#send/3">send/3,4,5</seealso> must be executed in the same process. </p> </desc> </func> diff --git a/lib/ssh/doc/src/ssh_protocol.xml b/lib/ssh/doc/src/ssh_protocol.xml new file mode 100644 index 0000000000..a0032ab449 --- /dev/null +++ b/lib/ssh/doc/src/ssh_protocol.xml @@ -0,0 +1,147 @@ +<?xml version="1.0" encoding="utf-8" ?> +<!DOCTYPE chapter SYSTEM "chapter.dtd"> +<!-- %EricssonCopyright% --> +<chapter> + <header> + <copyright> + <year>2013</year><year>2016</year> + <holder>Ericsson AB. All Rights Reserved.</holder> + </copyright> + <legalnotice> + The program may be used and/or copied only with the written permission from + Ericsson AB, or in accordance with the terms and conditions stipulated in + the agreement/contract under which the program has been supplied. + </legalnotice> + <title>Secure Shell (SSH)</title> + <prepared>OTP</prepared> + <date></date> + <rev>%VSN%</rev> + <file>ssh_protocol.xml</file> + </header> + + <section> + <title>SSH Protocol Overview</title> + + <p> Conceptually the SSH protocol can be partitioned into four + layers:</p> + + <image file="SSH_protocols.png"> + <icaption>SSH Protocol Architecture</icaption> + </image> + + <section> + <title>Transport Protocol</title> + + <p> The SSH Transport Protocol is a secure, low level transport. + It provides strong encryption, cryptographic host + authentication and integrity protection. Currently, only a + minimum of MAC- (message authentication code, a short piece of + information used to authenticate a message) and encryption + algorithms are supported see <seealso marker="ssh">ssh(3)</seealso> + </p> + </section> + + <section> + <title>Authentication Protocol</title> + + <p>The SSH authentication protocol is a general-purpose user + authentication protocol run over the SSH transport + protocol. Erlang SSH supports user authentication using public + key technology (RSA and DSA, X509-certificates are currently not + supported). It is also possible to use a so called keyboard + interactive authentication. This method is suitable for + interactive authentication methods that do not need any special + software support on the client side. Instead, all authentication + data should be entered via the keyboard. It is also possible + to use a pure password based authentication scheme, note that in + this case the the plain text password will be encrypted before sent + over the network. There are several configuration options for + authentication handling available in + <seealso marker="ssh#connect-3">ssh:connect/[3,4]</seealso> + and <seealso marker="ssh#daemon-2">ssh:daemon/[2,3]</seealso> + It is also possible to customize the public key handling + by implementing the behaviours <seealso + marker="ssh_client_key_api">ssh_client_key_api</seealso> and + <seealso + marker="ssh_server_key_api">ssh_server_key_api</seealso> + </p> + </section> + + <section> + <title>Connection Protocol</title> + + <p>The SSH Connection Protocol provides application-support + services over the transport pipe, such as channel multiplexing, + flow control, remote program execution, signal propagation, + connection forwarding, etc. Functions for handling the SSH + Connection Protocol can be found in the module <seealso + marker="ssh_connection">ssh_connection</seealso>. + </p> + </section> + + <section> + <title>Channels</title> + + <p>All terminal sessions, forwarded connections etc., are + channels. Multiple channels are multiplexed into a single + connection, and all channels are flow-controlled. Typically an + SSH client will open a channel, send data/commands, receive + data/"control information" and when it is done close the + channel. The <seealso + marker="ssh_channel">ssh_channel</seealso> behaviour makes it easy to + write your own SSH client/server processes that use flow + control. It handles generic parts of SSH channel management and + lets you focus on the application logic. + </p> + + <p>Channels comes in three flavors</p> + + <list type="bulleted"> + <item><em>Subsystem</em> - named services that can be run as + part of an SSH server such as SFTP <seealso + marker="ssh_sftpd">ssh_sftpd</seealso>, that is built in to the + SSH daemon (server) by default but may be disabled. The Erlang SSH + daemon may be configured to run any Erlang + implemented SSH subsystem. + </item> + <item><em>Shell</em> - interactive shell. By default the + Erlang daemon will run the Erlang shell. It is + possible to customize the shell by providing your own + read-eval-print loop. It is also possible, but much more work, + to provide your own CLI (Command Line Interface) implementation. + </item> + <item><em>Exec</em> - one-time remote execution of commands. See <seealso + marker="ssh_connection#exec-4">ssh_connection:exec/4</seealso></item> + </list> + </section> + + <p>Channels are flow controlled. No data may be sent to a channel + peer until a message is received to indicate that window space is + available. The 'initial window size' specifies how many bytes of + channel data that can be sent to the channel peer without adjusting the + window. + </p> + + <p> + For more detailed information about the SSH protocol, see the + following RFCs: + </p> + + <list type="bulleted"> + <item><url href="http://www.ietf.org/rfc/rfc4250.txt">RFC 4250</url> - + Protocol Assigned Numbers.</item> + <item><url href="http://www.ietf.org/rfc/rfc4251.txt">RFC 4251</url> - + Protocol Architecture.</item> + <item><url href="http://www.ietf.org/rfc/rfc4252.txt">RFC 4252</url> - + Authentication Protocol.</item> + <item><url href="http://www.ietf.org/rfc/rfc4253.txt">RFC 4253</url> - + Transport Layer Protocol.</item> + <item><url href="http://www.ietf.org/rfc/rfc4254.txt">RFC 4254</url> - + Connection Protocol.</item> + <item><url href="http://www.ietf.org/rfc/rfc4344.txt">RFC 4344</url> - + Transport Layer Encryption Modes.</item> + <item><url href="http://www.ietf.org/rfc/rfc4716.txt">RFC 4716</url> - + Public Key File Format.</item> + </list> + </section> +</chapter> diff --git a/lib/ssh/doc/src/ssh_server_key_api.xml b/lib/ssh/doc/src/ssh_server_key_api.xml new file mode 100644 index 0000000000..a0694ca8d9 --- /dev/null +++ b/lib/ssh/doc/src/ssh_server_key_api.xml @@ -0,0 +1,107 @@ +<?xml version="1.0" encoding="utf-8" ?> +<!DOCTYPE erlref SYSTEM "erlref.dtd"> + +<erlref> + <header> + <copyright> + <year>2012</year> + <year>2015</year> + <holder>Ericsson AB, All Rights Reserved</holder> + </copyright> + <legalnotice> + Licensed under the Apache License, Version 2.0 (the "License"); + you may not use this file except in compliance with the License. + You may obtain a copy of the License at + + http://www.apache.org/licenses/LICENSE-2.0 + + Unless required by applicable law or agreed to in writing, software + distributed under the License is distributed on an "AS IS" BASIS, + WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + See the License for the specific language governing permissions and + limitations under the License. + + The Initial Developer of the Original Code is Ericsson AB. + </legalnotice> + <title>ssh_server_key_api</title> + <prepared></prepared> + <docno></docno> + <date></date> + <rev></rev> + </header> + <module>ssh_server_key_api</module> + <modulesummary> + -behaviour(ssh_server_key_api). + </modulesummary> + <description> + <p>Behaviour describing the API for public key handling of an SSH server. By implementing + the callbacks defined in this behavior, the public key handling of an SSH server can + be customized. By default the SSH application implements this behavior + with help of the standard OpenSSH files, + see the <seealso marker="SSH_app"> ssh(6)</seealso> application manual.</p> + </description> + + <section> + <title>DATA TYPES</title> + + <p>Type definitions that are used more than once in this module, + or abstractions to indicate the intended use of the data + type, or both. For more details on public key data types, + refer to Section 2 Public Key Records in the + <seealso marker="public_key:public_key_records"> public_key user's guide</seealso>. + </p> + + <taglist> + <tag><c>boolean() =</c></tag> + <item><p><c>true | false</c></p></item> + <tag><c>string() =</c></tag> + <item><p><c>[byte()]</c></p></item> + <tag><c>public_key() =</c></tag> + <item><p><c>#'RSAPublicKey'{}| {integer(), #'Dss-Parms'{}}| term()</c></p></item> + <tag><c>private_key() =</c></tag> + <item><p><c>#'RSAPrivateKey'{} | #'DSAPrivateKey'{} | term()</c></p></item> + <tag><c>public_key_algorithm() =</c></tag> + <item><p><c>'ssh-rsa'| 'ssh-dss' | atom()</c></p></item> + </taglist> + </section> + + <funcs> + <func> + <name>Module:host_key(Algorithm, DaemonOptions) -> + {ok, Key} | {error, Reason}</name> + <fsummary>Fetches the host’s private key.</fsummary> + <type> + <v>Algorithm = public_key_algorithm()</v> + <d>Host key algorithm. Is to support <c>'ssh-rsa' | 'ssh-dss'</c>, but more algorithms + can be handled.</d> + <v>DaemonOptions = proplists:proplist()</v> + <d>Options provided to <seealso marker="ssh#daemon-2">ssh:daemon/[2,3]</seealso>.</d> + <v>Key = private_key()</v> + <d>Private key of the host matching the <c>Algorithm</c>.</d> + <v>Reason = term()</v> + </type> + <desc> + <p>Fetches the private key of the host.</p> + </desc> + </func> + + <func> + <name>Module:is_auth_key(Key, User, DaemonOptions) -> Result</name> + <fsummary>Checks if the user key is authorized.</fsummary> + <type> + <v>Key = public_key()</v> + <d>Normally an RSA or DSA public key, but handling of other public keys can be added</d> + <v>User = string()</v> + <d>User owning the public key.</d> + <v>DaemonOptions = proplists:proplist()</v> + <d>Options provided to <seealso marker="ssh#daemon-2">ssh:daemon/[2,3]</seealso>.</d> + <v>Result = boolean()</v> + </type> + <desc> + <p>Checks if the user key is authorized.</p> + </desc> + </func> + + </funcs> + +</erlref> diff --git a/lib/ssh/doc/src/ssh_sftp.xml b/lib/ssh/doc/src/ssh_sftp.xml index c1f75461b1..eb6f43d417 100644 --- a/lib/ssh/doc/src/ssh_sftp.xml +++ b/lib/ssh/doc/src/ssh_sftp.xml @@ -1,331 +1,356 @@ -<?xml version="1.0" encoding="latin1" ?> +<?xml version="1.0" encoding="utf-8" ?> <!DOCTYPE erlref SYSTEM "erlref.dtd"> <erlref> <header> <copyright> - <year>2005</year><year>2010</year> + <year>2005</year><year>2016</year> <holder>Ericsson AB. All Rights Reserved.</holder> </copyright> <legalnotice> - The contents of this file are subject to the Erlang Public License, - Version 1.1, (the "License"); you may not use this file except in - compliance with the License. You should have received a copy of the - Erlang Public License along with this software. If not, it can be - retrieved online at http://www.erlang.org/. + Licensed under the Apache License, Version 2.0 (the "License"); + you may not use this file except in compliance with the License. + You may obtain a copy of the License at + + http://www.apache.org/licenses/LICENSE-2.0 - Software distributed under the License is distributed on an "AS IS" - basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See - the License for the specific language governing rights and limitations - under the License. + Unless required by applicable law or agreed to in writing, software + distributed under the License is distributed on an "AS IS" BASIS, + WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + See the License for the specific language governing permissions and + limitations under the License. </legalnotice> <title>ssh_sftp</title> - <prepared>Jakob Cederlund</prepared> - <responsible></responsible> - <docno>1</docno> - <approved></approved> - <checked></checked> + <prepared>OTP</prepared> + <docno></docno> <date>2005-09-22</date> - <rev>PA1</rev> + <rev></rev> <file>ssh_sftp.sgml</file> </header> <module>ssh_sftp</module> <modulesummary>SFTP client.</modulesummary> <description> - <p>This module implements an SFTP (SSH FTP) client. SFTP is a - secure, encrypted file transfer service available for - SSH.</p> + <p>This module implements an SSH FTP (SFTP) client. SFTP is a + secure, encrypted file transfer service available for + SSH.</p> </description> <section> - <title>COMMON DATA TYPES </title> - <p>Type definitions that are used more than once in this module - and/or abstractions to indicate the intended use of the data type: + <title>DATA TYPES</title> + <p>Type definitions that are used more than once in this module, + or abstractions to indicate the intended use of the data type, or both: </p> - <p><c>ssh_connection_ref() - opaque to the user - returned by ssh:connect/3</c></p> - <p><c>timeout() = infinity | integer() - in milliseconds.</c></p> + + <taglist> + <tag><c>reason()</c></tag> + <item> + <p>= <c>atom()</c> A description of the reason why an operation failed.</p> + <p> + The value is formed from the sftp error codes in the protocol-level responses as defined in + <url href="https://tools.ietf.org/id/draft-ietf-secsh-filexfer-13.txt">draft-ietf-secsh-filexfer-13.txt</url> + section 9.1. + </p> + <p> + The codes are named as <c>SSH_FX_*</c> which are transformed into lowercase of the star-part. + E.g. the error code <c>SSH_FX_NO_SUCH_FILE</c> + will cause the <c>reason()</c> to be <c>no_such_file</c>. + </p> + </item> + + <tag><c>ssh_connection_ref() =</c></tag> + <item><p><c>opaque()</c> - as returned by + <seealso marker="ssh#connect-3"><c>ssh:connect/3</c></seealso></p></item> + + <tag><c>timeout()</c></tag> + <item><p>= <c>infinity | integer()</c> in milliseconds. Default infinity.</p></item> + </taglist> </section> <section> - <title>TIMEOUTS </title> - <p>If the request functions for the sftp channel return {error, timeout} - it does not mean that the request did not reach the server and was - not performed, it only means that we did not receive an answer from the - server within the time that was expected.</p> + <title>Time-outs</title> + <p>If the request functions for the SFTP channel return <c>{error, timeout}</c>, + no answer was received from the server within the expected time.</p> + <p>The request may have reached the server and may have been performed. + However, no answer was received from the server within the expected time.</p> </section> <funcs> - <func> - <name>start_channel(ConnectionRef) -> </name> - <name>start_channel(ConnectionRef, Options) -> </name> - <name>start_channel(Host, Options) -></name> - <name>start_channel(Host, Port, Options) -> {ok, Pid} | {ok, Pid, ConnectionRef} | - {error, Reason}</name> - <fsummary>Starts a sftp client</fsummary> - <type> - <v>Host = string()</v> - <v>ConnectionRef = ssh_connection_ref()</v> - <v>Port = integer()</v> - <v>Options = [{Option, Value}]</v> - <v>Reason = term()</v> - </type> - <desc> - <p>If not provided, setups a ssh connection in this case a - connection reference will be returned too. A ssh channel - process is started to handle the communication with the SFTP - server, the returned pid for this process should be used as - input to all other API functions in this module.</p> - - <p>Options are:</p> - <taglist> - <tag><c><![CDATA[{timeout, timeout()}]]></c></tag> - <item> - <p>The timeout is passed to the ssh_channel start function, - and defaults to infinity.</p> - </item> - </taglist> - <p>All other options are directly passed to - <seealso marker="ssh">ssh:connect/3</seealso> or ignored if a - connection is already provided. </p> + <func> + <name>apread(ChannelPid, Handle, Position, Len) -> {async, N} | {error, reason()}</name> + <fsummary>Reads asynchronously from an open file.</fsummary> + <type> + <v>ChannelPid = pid()</v> + <v>Handle = term()</v> + <v>Position = integer()</v> + <v>Len = integer()</v> + <v>N = term()</v> + </type> + <desc><p>The <c><![CDATA[apread/4]]></c> function reads from a specified position, + combining the <seealso marker="#position-3"><c>position/3</c></seealso> and + <seealso marker="#aread-3"><c>aread/3</c></seealso> functions.</p> + </desc> + </func> + + <func> + <name>apwrite(ChannelPid, Handle, Position, Data) -> {async, N} | {error, reason()}</name> + <fsummary>Writes asynchronously to an open file.</fsummary> + <type> + <v>ChannelPid = pid()</v> + <v>Handle = term()</v> + <v>Position = integer()</v> + <v>Len = integer()</v> + <v>Data = binary()</v> + <v>Timeout = timeout()</v> + <v>N = term()</v> + </type> + <desc><p>The <c><![CDATA[apwrite/4]]></c> function writes to a specified position, + combining the <seealso marker="#position-3"><c>position/3</c></seealso> and + <seealso marker="#awrite-3"><c>awrite/3</c></seealso> functions.</p> + </desc> + </func> + + <func> + <name>aread(ChannelPid, Handle, Len) -> {async, N} | {error, reason()}</name> + <fsummary>Reads asynchronously from an open file.</fsummary> + <type> + <v>ChannelPid = pid()</v> + <v>Handle = term()</v> + <v>Position = integer()</v> + <v>Len = integer()</v> + <v>N = term()</v> + </type> + <desc> + <p>Reads from an open file, without waiting for the result. If the + handle is valid, the function returns <c><![CDATA[{async, N}]]></c>, where <c>N</c> + is a term guaranteed to be unique between calls of <c><![CDATA[aread]]></c>. + The actual data is sent as a message to the calling process. This + message has the form <c><![CDATA[{async_reply, N, Result}]]></c>, where + <c><![CDATA[Result]]></c> is the result from the read, either <c><![CDATA[{ok, Data}]]></c>, + <c><![CDATA[eof]]></c>, or <c><![CDATA[{error, reason()}]]></c>.</p> </desc> </func> <func> - <name>stop_channel(ChannelPid) -> ok</name> - <fsummary>Stops the sftp client channel.</fsummary> + <name>awrite(ChannelPid, Handle, Data) -> {async, N} | {error, reason()}</name> + <fsummary>Writes asynchronously to an open file.</fsummary> <type> <v>ChannelPid = pid()</v> - </type> - <desc> - <p>Stops a sftp channel. If the ssh connection should be closed - call <seealso marker="ssh">ssh:close/1</seealso>.</p> - </desc> - </func> - - <func> - <name>read_file(ChannelPid, File) -> </name> - <name>read_file(ChannelPid, File, Timeout) -> {ok, Data} | {error, Reason}</name> - <fsummary>Read a file</fsummary> - <type> - <v>ChannelPid = pid()</v> - <v>File = string()</v> + <v>Handle = term()</v> + <v>Position = integer()</v> + <v>Len = integer()</v> <v>Data = binary()</v> <v>Timeout = timeout()</v> - <v>Reason = term()</v> </type> <desc> - <p>Reads a file from the server, and returns the data in a binary, - like <c><![CDATA[file:read_file/1]]></c>.</p> + <p>Writes to an open file, without waiting for the result. If the + handle is valid, the function returns <c><![CDATA[{async, N}]]></c>, where <c>N</c> + is a term guaranteed to be unique between calls of + <c><![CDATA[awrite]]></c>. The result of the <c><![CDATA[write]]></c> operation is sent + as a message to the calling process. This message has the form + <c><![CDATA[{async_reply, N, Result}]]></c>, where <c><![CDATA[Result]]></c> is the result + from the write, either <c><![CDATA[ok]]></c>, or <c><![CDATA[{error, reason()}]]></c>.</p> </desc> </func> + <func> - <name>write_file(ChannelPid, File, Iolist) -> </name> - <name>write_file(ChannelPid, File, Iolist, Timeout) -> ok | {error, Reason}</name> - <fsummary>Write a file</fsummary> + <name>close(ChannelPid, Handle) -></name> + <name>close(ChannelPid, Handle, Timeout) -> ok | {error, reason()}</name> + <fsummary>Closes an open handle.</fsummary> <type> <v>ChannelPid = pid()</v> - <v>File = string()</v> - <v>Iolist = iolist()</v> + <v>Handle = term()</v> <v>Timeout = timeout()</v> - <v>Reason = term()</v> </type> <desc> - <p>Writes a file to the server, like <c><![CDATA[file:write_file/2]]></c>. - The file is created if it's not there.</p> + <p>Closes a handle to an open file or directory on the server.</p> </desc> </func> + <func> - <name>list_dir(ChannelPid, Path) -> </name> - <name>list_dir(ChannelPid, Path, Timeout) -> {ok, Filenames} | {error, Reason}</name> - <fsummary>List directory</fsummary> + <name>delete(ChannelPid, Name) -></name> + <name>delete(ChannelPid, Name, Timeout) -> ok | {error, reason()}</name> + <fsummary>Deletes a file.</fsummary> <type> <v>ChannelPid = pid()</v> - <v>Path = string()</v> - <v>Filenames = [Filename]</v> - <v>Filename = string()</v> + <v>Name = string()</v> <v>Timeout = timeout()</v> - <v>Reason = term()</v> </type> <desc> - <p>Lists the given directory on the server, returning the - filenames as a list of strings.</p> + <p>Deletes the file specified by <c><![CDATA[Name]]></c>. + </p> </desc> </func> + <func> - <name>open(ChannelPid, File, Mode) -> </name> - <name>open(ChannelPid, File, Mode, Timeout) -> {ok, Handle} | {error, Reason}</name> - <fsummary>Open a file and return a handle</fsummary> + <name>del_dir(ChannelPid, Name) -></name> + <name>del_dir(ChannelPid, Name, Timeout) -> ok | {error, reason()}</name> + <fsummary>Deletes an empty directory.</fsummary> <type> <v>ChannelPid = pid()</v> - <v>File = string()</v> - <v>Mode = [Modeflag]</v> - <v>Modeflag = read | write | creat | trunc | append | binary</v> + <v>Name = string()</v> <v>Timeout = timeout()</v> - <v>Handle = term()</v> - <v>Reason = term()</v> </type> <desc> - <p>Opens a file on the server, and returns a handle that - is used for reading or writing.</p> + <p>Deletes a directory specified by <c><![CDATA[Name]]></c>. + The directory must be empty before it can be successfully deleted. + </p> </desc> </func> - <func> - <name>opendir(ChannelPid, Path) -> </name> - <name>opendir(ChannelPid, Path, Timeout) -> {ok, Handle} | {error, Reason}</name> - <fsummary>Open a directory and return a handle</fsummary> + + <func> + <name>list_dir(ChannelPid, Path) -></name> + <name>list_dir(ChannelPid, Path, Timeout) -> {ok, Filenames} | {error, reason()}</name> + <fsummary>Lists the directory.</fsummary> <type> <v>ChannelPid = pid()</v> <v>Path = string()</v> + <v>Filenames = [Filename]</v> + <v>Filename = string()</v> <v>Timeout = timeout()</v> - <v>Reason = term()</v> </type> <desc> - <p>Opens a handle to a directory on the server, the handle - is used for reading directory contents.</p> + <p>Lists the given directory on the server, returning the + filenames as a list of strings.</p> </desc> </func> + <func> - <name>close(ChannelPid, Handle) -> </name> - <name>close(ChannelPid, Handle, Timeout) -> ok | {error, Reason}</name> - <fsummary>Close an open handle</fsummary> + <name>make_dir(ChannelPid, Name) -></name> + <name>make_dir(ChannelPid, Name, Timeout) -> ok | {error, reason()}</name> + <fsummary>Creates a directory.</fsummary> <type> <v>ChannelPid = pid()</v> - <v>Handle = term()</v> + <v>Name = string()</v> <v>Timeout = timeout()</v> - <v>Reason = term()</v> </type> <desc> - <p>Closes a handle to an open file or directory on the server.</p> + <p>Creates a directory specified by <c><![CDATA[Name]]></c>. <c><![CDATA[Name]]></c> + must be a full path to a new directory. The directory can only be + created in an existing directory.</p> </desc> </func> + <func> - <name>read(ChannelPid, Handle, Len) -> </name> - <name>read(ChannelPid, Handle, Len, Timeout) -> {ok, Data} | eof | {error, Error}</name> - <name>pread(ChannelPid, Handle, Position, Len) -> </name> - <name>pread(ChannelPid, Handle, Position, Len, Timeout) -> {ok, Data} | eof | {error, Error}</name> - <fsummary>Read from an open file</fsummary> + <name>make_symlink(ChannelPid, Name, Target) -></name> + <name>make_symlink(ChannelPid, Name, Target, Timeout) -> ok | {error, reason()}</name> + <fsummary>Creates a symbolic link.</fsummary> <type> <v>ChannelPid = pid()</v> - <v>Handle = term()</v> - <v>Position = integer()</v> - <v>Len = integer()</v> - <v>Timeout = timeout()</v> - <v>Data = string() | binary()</v> - <v>Reason = term()</v> + <v>Name = string()</v> + <v>Target = string()</v> </type> <desc> - <p>Reads <c><![CDATA[Len]]></c> bytes from the file referenced by - <c><![CDATA[Handle]]></c>. Returns <c><![CDATA[{ok, Data}]]></c>, or <c><![CDATA[eof]]></c>, or - <c><![CDATA[{error, Reason}]]></c>. If the file is opened with <c><![CDATA[binary]]></c>, - <c><![CDATA[Data]]></c> is a binary, otherwise it is a string.</p> - <p>If the file is read past eof, only the remaining bytes - will be read and returned. If no bytes are read, <c><![CDATA[eof]]></c> - is returned.</p> - <p>The <c><![CDATA[pread]]></c> function reads from a specified position, - combining the <c><![CDATA[position]]></c> and <c><![CDATA[read]]></c> functions.</p> + <p>Creates a symbolic link pointing to <c><![CDATA[Target]]></c> with the + name <c><![CDATA[Name]]></c>. + </p> </desc> </func> - <func> - <name>aread(ChannelPid, Handle, Len) -> {async, N} | {error, Error}</name> - <name>apread(ChannelPid, Handle, Position, Len) -> {async, N} | {error, Error}</name> - <fsummary>Read asynchronously from an open file</fsummary> + + <func> + <name>open(ChannelPid, File, Mode) -></name> + <name>open(ChannelPid, File, Mode, Timeout) -> {ok, Handle} | {error, reason()}</name> + <fsummary>Opens a file and returns a handle.</fsummary> <type> <v>ChannelPid = pid()</v> - <v>Handle = term()</v> - <v>Position = integer()</v> - <v>Len = integer()</v> - <v>N = term()</v> - <v>Reason = term()</v> + <v>File = string()</v> + <v>Mode = [Modeflag]</v> + <v>Modeflag = read | write | creat | trunc | append | binary</v> + <v>Timeout = timeout()</v> + <v>Handle = term()</v> </type> <desc> - <p>Reads from an open file, without waiting for the result. If the - handle is valid, the function returns <c><![CDATA[{async, N}]]></c>, where N - is a term guaranteed to be unique between calls of <c><![CDATA[aread]]></c>. - The actual data is sent as a message to the calling process. This - message has the form <c><![CDATA[{async_reply, N, Result}]]></c>, where - <c><![CDATA[Result]]></c> is the result from the read, either <c><![CDATA[{ok, Data}]]></c>, - or <c><![CDATA[eof]]></c>, or <c><![CDATA[{error, Error}]]></c>.</p> - <p>The <c><![CDATA[apread]]></c> function reads from a specified position, - combining the <c><![CDATA[position]]></c> and <c><![CDATA[aread]]></c> functions.</p> + <p>Opens a file on the server and returns a handle, which + can be used for reading or writing.</p> </desc> </func> <func> - <name>write(ChannelPid, Handle, Data) -></name> - <name>write(ChannelPid, Handle, Data, Timeout) -> ok | {error, Error}</name> - <name>pwrite(ChannelPid, Handle, Position, Data) -> ok </name> - <name>pwrite(ChannelPid, Handle, Position, Data, Timeout) -> ok | {error, Error}</name> - <fsummary>Write to an open file</fsummary> + <name>opendir(ChannelPid, Path) -></name> + <name>opendir(ChannelPid, Path, Timeout) -> {ok, Handle} | {error, reason()}</name> + <fsummary>Opens a directory and returns a handle.</fsummary> <type> <v>ChannelPid = pid()</v> - <v>Handle = term()</v> - <v>Position = integer()</v> - <v>Data = iolist()</v> + <v>Path = string()</v> <v>Timeout = timeout()</v> - <v>Reason = term()</v> </type> <desc> - <p>Write <c><![CDATA[data]]></c> to the file referenced by <c><![CDATA[Handle]]></c>. - The file should be opened with <c><![CDATA[write]]></c> or <c><![CDATA[append]]></c> - flag. Returns <c><![CDATA[ok]]></c> if successful and <c><![CDATA[{error, Reason}]]></c> - otherwise.</p> - <p>Typical error reasons are:</p> - <taglist> - <tag><c><![CDATA[ebadf]]></c></tag> - <item> - <p>The file is not opened for writing.</p> - </item> - <tag><c><![CDATA[enospc]]></c></tag> - <item> - <p>There is a no space left on the device.</p> - </item> - </taglist> + <p>Opens a handle to a directory on the server. The handle + can be used for reading directory contents.</p> </desc> </func> + <func> - <name>awrite(ChannelPid, Handle, Data) -> ok | {error, Reason} </name> - <name>apwrite(ChannelPid, Handle, Position, Data) -> ok | {error, Reason}</name> - <fsummary>Write asynchronously to an open file</fsummary> + <name>open_tar(ChannelPid, Path, Mode) -></name> + <name>open_tar(ChannelPid, Path, Mode, Timeout) -> {ok, Handle} | {error, reason()}</name> + <fsummary>Opens a tar file on the server to which <c>ChannelPid</c> + is connected and returns a handle.</fsummary> <type> <v>ChannelPid = pid()</v> - <v>Handle = term()</v> - <v>Position = integer()</v> - <v>Len = integer()</v> - <v>Data = binary()</v> + <v>Path = string()</v> + <v>Mode = [read] | [write] | [read,EncryptOpt] | [write,DecryptOpt]</v> + <v>EncryptOpt = {crypto,{InitFun,EncryptFun,CloseFun}}</v> + <v>DecryptOpt = {crypto,{InitFun,DecryptFun}}</v> + <v>InitFun = (fun() -> {ok,CryptoState}) | (fun() -> {ok,CryptoState,ChunkSize})</v> + <v>CryptoState = any()</v> + <v>ChunkSize = undefined | pos_integer()</v> + <v>EncryptFun = (fun(PlainBin,CryptoState) -> EncryptResult)</v> + <v>EncryptResult = {ok,EncryptedBin,CryptoState} | {ok,EncryptedBin,CryptoState,ChunkSize}</v> + <v>PlainBin = binary()</v> + <v>EncryptedBin = binary()</v> + <v>DecryptFun = (fun(EncryptedBin,CryptoState) -> DecryptResult)</v> + <v>DecryptResult = {ok,PlainBin,CryptoState} | {ok,PlainBin,CryptoState,ChunkSize}</v> + <v>CloseFun = (fun(PlainBin,CryptoState) -> {ok,EncryptedBin})</v> <v>Timeout = timeout()</v> - <v>Reason = term()</v> </type> <desc> - <p>Writes to an open file, without waiting for the result. If the - handle is valid, the function returns <c><![CDATA[{async, N}]]></c>, where N - is a term guaranteed to be unique between calls of - <c><![CDATA[awrite]]></c>. The result of the <c><![CDATA[write]]></c> operation is sent - as a message to the calling process. This message has the form - <c><![CDATA[{async_reply, N, Result}]]></c>, where <c><![CDATA[Result]]></c> is the result - from the write, either <c><![CDATA[ok]]></c>, or <c><![CDATA[{error, Error}]]></c>.</p> - <p>The <c><![CDATA[apwrite]]></c> writes on a specified position, combining - the <c><![CDATA[position]]></c> and <c><![CDATA[awrite]]></c> operations.</p> + <p>Opens a handle to a tar file on the server, associated with <c>ChannelPid</c>. + The handle can be used for remote tar creation and extraction, as defined by the + <seealso marker="stdlib:erl_tar#init-3">erl_tar:init/3</seealso> function. + </p> + + <p> For code exampel see Section + <seealso marker="using_ssh">SFTP Client with TAR Compression and Encryption</seealso> in + the ssh Users Guide. </p> + + <p>The <c>crypto</c> mode option is applied to the generated stream of bytes prior to sending + them to the SFTP server. This is intended for encryption but can be used for other + purposes. + </p> + <p>The <c>InitFun</c> is applied once + prior to any other <c>crypto</c> operation. The returned <c>CryptoState</c> is then folded into + repeated applications of the <c>EncryptFun</c> or <c>DecryptFun</c>. The binary returned + from those funs are sent further to the remote SFTP server. Finally, if doing encryption, + the <c>CloseFun</c> is applied to the last piece of data. The <c>CloseFun</c> is + responsible for padding (if needed) and encryption of that last piece. + </p> + <p>The <c>ChunkSize</c> defines the size of the <c>PlainBin</c>s that <c>EncodeFun</c> is applied + to. If the <c>ChunkSize</c> is <c>undefined</c>, the size of the <c>PlainBin</c>s varies, + because this is intended for stream crypto, whereas a fixed <c>ChunkSize</c> is intended for block crypto. + <c>ChunkSize</c>s can be changed in the return from the <c>EncryptFun</c> or + <c>DecryptFun</c>. The value can be changed between <c>pos_integer()</c> and <c>undefined</c>. + </p> + </desc> </func> + <func> - <name>position(ChannelPid, Handle, Location) -> </name> - <name>position(ChannelPid, Handle, Location, Timeout) -> {ok, NewPosition | {error, Error}</name> - <fsummary>Seek position in open file</fsummary> + <name>position(ChannelPid, Handle, Location) -></name> + <name>position(ChannelPid, Handle, Location, Timeout) -> {ok, NewPosition | {error, reason()}</name> + <fsummary>Sets the file position of a file.</fsummary> <type> <v>ChannelPid = pid()</v> <v>Handle = term()</v> - <v>Location = Offset | {bof, Offset} | {cur, Offset} | {eof, Offset} | bof | cur | eof</v> - <v>Offset = int()</v> + <v>Location = Offset + | {bof, Offset} | {cur, Offset} | {eof, Offset} | bof | cur | eof</v> + <v>Offset = integer()</v> <v>Timeout = timeout()</v> <v>NewPosition = integer()</v> - <v>Reason = term()</v> </type> <desc> <p>Sets the file position of the file referenced by <c><![CDATA[Handle]]></c>. - Returns <c><![CDATA[{ok, NewPosition]]></c> (as an absolute offset) if - successful, otherwise <c><![CDATA[{error, Reason}]]></c>. <c><![CDATA[Location]]></c> is + Returns <c><![CDATA[{ok, NewPosition}]]></c> (as an absolute offset) if + successful, otherwise <c><![CDATA[{error, reason()}]]></c>. <c><![CDATA[Location]]></c> is one of the following:</p> <taglist> <tag><c><![CDATA[Offset]]></c></tag> @@ -346,156 +371,280 @@ </item> <tag><c><![CDATA[bof | cur | eof]]></c></tag> <item> - <p>The same as above with <c><![CDATA[Offset]]></c> 0.</p> + <p>The same as eariler with <c><![CDATA[Offset]]></c> 0, + that is, <c><![CDATA[{bof, 0} | {cur, 0} | {eof, 0}]]></c>. + </p> </item> </taglist> </desc> </func> + <func> - <name>read_file_info(ChannelPid, Name) -> </name> - <name>read_file_info(ChannelPid, Name, Timeout) -> {ok, FileInfo} | {error, Reason}</name> - <fsummary>Get information about a file</fsummary> + <name>pread(ChannelPid, Handle, Position, Len) -></name> + <name>pread(ChannelPid, Handle, Position, Len, Timeout) -> {ok, Data} | eof | {error, reason()}</name> + <fsummary>Reads from an open file.</fsummary> <type> <v>ChannelPid = pid()</v> - <v>Name = string()</v> <v>Handle = term()</v> + <v>Position = integer()</v> + <v>Len = integer()</v> <v>Timeout = timeout()</v> - <v>FileInfo = record()</v> - <v>Reason = term()</v> + <v>Data = string() | binary()</v> </type> - <desc> - <p>Returns a <c><![CDATA[file_info]]></c> record from the file specified by - <c><![CDATA[Name]]></c> or <c><![CDATA[Handle]]></c>, like <c><![CDATA[file:read_file_info/2]]></c>.</p> - </desc> + <desc><p>The <c><![CDATA[pread/3,4]]></c> function reads from a specified position, + combining the <seealso marker="#position-3"><c>position/3</c></seealso> and + <seealso marker="#read-3"><c>read/3,4</c></seealso> functions.</p> + </desc> + </func> + + <func> + <name>pwrite(ChannelPid, Handle, Position, Data) -> ok</name> + <name>pwrite(ChannelPid, Handle, Position, Data, Timeout) -> ok | {error, reason()}</name> + <fsummary>Writes to an open file.</fsummary> + <type> + <v>ChannelPid = pid()</v> + <v>Handle = term()</v> + <v>Position = integer()</v> + <v>Data = iolist()</v> + <v>Timeout = timeout()</v> + </type> + <desc><p>The <c><![CDATA[pwrite/3,4]]></c> function writes to a specified position, + combining the <seealso marker="#position-3"><c>position/3</c></seealso> and + <seealso marker="#write-3"><c>write/3,4</c></seealso> functions.</p> + </desc> </func> + <func> - <name>read_link_info(ChannelPid, Name) -> {ok, FileInfo} | {error, Reason}</name> - <name>read_link_info(ChannelPid, Name, Timeout) -> {ok, FileInfo} | {error, Reason}</name> - <fsummary>Get information about a symbolic link</fsummary> + <name>read(ChannelPid, Handle, Len) -></name> + <name>read(ChannelPid, Handle, Len, Timeout) -> {ok, Data} | eof | {error, reason()}</name> + <fsummary>Reads from an open file.</fsummary> <type> <v>ChannelPid = pid()</v> - <v>Name = string()</v> <v>Handle = term()</v> + <v>Position = integer()</v> + <v>Len = integer()</v> <v>Timeout = timeout()</v> - <v>FileInfo = record()</v> - <v>Reason = term()</v> + <v>Data = string() | binary()</v> </type> <desc> - <p>Returns a <c><![CDATA[file_info]]></c> record from the symbolic - link specified by <c><![CDATA[Name]]></c> or <c><![CDATA[Handle]]></c>, like - <c><![CDATA[file:read_link_info/2]]></c>.</p> + <p>Reads <c><![CDATA[Len]]></c> bytes from the file referenced by + <c><![CDATA[Handle]]></c>. Returns <c><![CDATA[{ok, Data}]]></c>, <c><![CDATA[eof]]></c>, or + <c><![CDATA[{error, reason()}]]></c>. If the file is opened with <c><![CDATA[binary]]></c>, + <c><![CDATA[Data]]></c> is a binary, otherwise it is a string.</p> + <p>If the file is read past <c>eof</c>, only the remaining bytes + are read and returned. If no bytes are read, <c><![CDATA[eof]]></c> + is returned.</p> </desc> </func> - <func> - <name>write_file_info(ChannelPid, Name, Info) -> </name> - <name>write_file_info(ChannelPid, Name, Info, Timeout) -> ok | {error, Reason}</name> - <fsummary>Write information for a file</fsummary> + + <func> + <name>read_file(ChannelPid, File) -></name> + <name>read_file(ChannelPid, File, Timeout) -> {ok, Data} | {error, reason()}</name> + <fsummary>Reads a file.</fsummary> + <type> + <v>ChannelPid = pid()</v> + <v>File = string()</v> + <v>Data = binary()</v> + <v>Timeout = timeout()</v> + </type> + <desc> + <p>Reads a file from the server, and returns the data in a binary.</p> + </desc> + </func> + + <func> + <name>read_file_info(ChannelPid, Name) -></name> + <name>read_file_info(ChannelPid, Name, Timeout) -> {ok, FileInfo} | {error, reason()}</name> + <fsummary>Gets information about a file.</fsummary> <type> <v>ChannelPid = pid()</v> <v>Name = string()</v> - <v>Info = record()</v> + <v>Handle = term()</v> <v>Timeout = timeout()</v> - <v>Reason = term()</v> + <v>FileInfo = record()</v> </type> <desc> - <p>Writes file information from a <c><![CDATA[file_info]]></c> record to the - file specified by <c><![CDATA[Name]]></c>, like <c><![CDATA[file:write_file_info]]></c>.</p> + <p>Returns a <c><![CDATA[file_info]]></c> record from the file specified by + <c><![CDATA[Name]]></c> or <c><![CDATA[Handle]]></c>. See + <seealso marker="kernel:file#read_file_info-2">file:read_file_info/2</seealso> + for information about the record. + </p> </desc> </func> - <func> - <name>read_link(ChannelPid, Name) -> </name> - <name>read_link(ChannelPid, Name, Timeout) -> {ok, Target} | {error, Reason}</name> - <fsummary>Read symbolic link</fsummary> + + <func> + <name>read_link(ChannelPid, Name) -></name> + <name>read_link(ChannelPid, Name, Timeout) -> {ok, Target} | {error, reason()}</name> + <fsummary>Reads symbolic link.</fsummary> <type> <v>ChannelPid = pid()</v> <v>Name = string()</v> <v>Target = string()</v> - <v>Reason = term()</v> </type> <desc> - <p>Read the link target from the symbolic link specified - by <c><![CDATA[name]]></c>, like <c><![CDATA[file:read_link/1]]></c>.</p> + <p>Reads the link target from the symbolic link specified by <c><![CDATA[name]]></c>. + </p> </desc> </func> - <func> - <name>make_symlink(ChannelPid, Name, Target) -> </name> - <name>make_symlink(ChannelPid, Name, Target, Timeout) -> ok | {error, Reason}</name> - <fsummary>Create symbolic link</fsummary> + + <func> + <name>read_link_info(ChannelPid, Name) -> {ok, FileInfo} | {error, reason()}</name> + <name>read_link_info(ChannelPid, Name, Timeout) -> {ok, FileInfo} | {error, reason()}</name> + <fsummary>Gets information about a symbolic link.</fsummary> <type> <v>ChannelPid = pid()</v> <v>Name = string()</v> - <v>Target = string()</v> - <v>Reason = term()</v> + <v>Handle = term()</v> + <v>Timeout = timeout()</v> + <v>FileInfo = record()</v> </type> <desc> - <p>Creates a symbolic link pointing to <c><![CDATA[Target]]></c> with the - name <c><![CDATA[Name]]></c>, like <c><![CDATA[file:make_symlink/2]]></c>.</p> + <p>Returns a <c><![CDATA[file_info]]></c> record from the symbolic + link specified by <c><![CDATA[Name]]></c> or <c><![CDATA[Handle]]></c>. + See + <seealso marker="kernel:file#read_link_info-2">file:read_link_info/2</seealso> + for information about the record. + </p> </desc> </func> + <func> - <name>rename(ChannelPid, OldName, NewName) -> </name> - <name>rename(ChannelPid, OldName, NewName, Timeout) -> ok | {error, Reason}</name> - <fsummary>Rename a file</fsummary> + <name>rename(ChannelPid, OldName, NewName) -> </name> + <name>rename(ChannelPid, OldName, NewName, Timeout) -> ok | {error, reason()}</name> + <fsummary>Renames a file.</fsummary> <type> <v>ChannelPid = pid()</v> <v>OldName = string()</v> <v>NewName = string()</v> <v>Timeout = timeout()</v> - <v>Reason = term()</v> </type> <desc> - <p>Renames a file named <c><![CDATA[OldName]]></c>, and gives it the name - <c><![CDATA[NewName]]></c>, like <c><![CDATA[file:rename/2]]></c></p> + <p>Renames a file named <c><![CDATA[OldName]]></c> and gives it the name + <c><![CDATA[NewName]]></c>. + </p> </desc> </func> + <func> - <name>delete(ChannelPid, Name) -> </name> - <name>delete(ChannelPid, Name, Timeout) -> ok | {error, Reason}</name> - <fsummary>Delete a file</fsummary> + <name>start_channel(ConnectionRef) -></name> + <name>start_channel(ConnectionRef, Options) -> + {ok, Pid} | {error, reason()|term()}</name> + + <name>start_channel(Host, Options) -></name> + <name>start_channel(Host, Port, Options) -> + {ok, Pid, ConnectionRef} | {error, reason()|term()}</name> + + <name>start_channel(TcpSocket) -></name> + <name>start_channel(TcpSocket, Options) -> + {ok, Pid, ConnectionRef} | {error, reason()|term()}</name> + + <fsummary>Starts an SFTP client.</fsummary> + <type> + <v>Host = string()</v> + <v>ConnectionRef = ssh_connection_ref()</v> + <v>Port = integer()</v> + <v>TcpSocket = port()</v> + <d>The socket is supposed to be from <seealso marker="kernel:gen_tcp#connect-3">gen_tcp:connect</seealso> or <seealso marker="kernel:gen_tcp#accept-1">gen_tcp:accept</seealso> with option <c>{active,false}</c></d> + <v>Options = [{Option, Value}]</v> + </type> + <desc> + <p>If no connection reference is provided, a connection is set + up, and the new connection is returned. An SSH channel process + is started to handle the communication with the SFTP server. + The returned <c>pid</c> for this process is to be used as input to + all other API functions in this module.</p> + + <p>Options:</p> + <taglist> + <tag><c><![CDATA[{timeout, timeout()}]]></c></tag> + <item> + <p>The time-out is passed to the <c>ssh_channel</c> start function, + and defaults to <c>infinity</c>.</p> + </item> + <tag> + <c><![CDATA[{sftp_vsn, integer()}]]></c> + </tag> + <item> + <p> + Desired SFTP protocol version. + The actual version is the minimum of + the desired version and the maximum supported + versions by the SFTP server. + </p> + </item> + </taglist> + <p>All other options are directly passed to + <seealso marker="ssh">ssh:connect/3</seealso> or ignored if a + connection is already provided.</p> + </desc> + </func> + + <func> + <name>stop_channel(ChannelPid) -> ok</name> + <fsummary>Stops the SFTP client channel.</fsummary> <type> <v>ChannelPid = pid()</v> - <v>Name = string()</v> + </type> + <desc> + <p>Stops an SFTP channel. Does not close the SSH connection. + Use <seealso marker="ssh#close-1">ssh:close/1</seealso> to close it.</p> + </desc> + </func> + + <func> + <name>write(ChannelPid, Handle, Data) -></name> + <name>write(ChannelPid, Handle, Data, Timeout) -> ok | {error, reason()}</name> + <fsummary>Writes to an open file.</fsummary> + <type> + <v>ChannelPid = pid()</v> + <v>Handle = term()</v> + <v>Position = integer()</v> + <v>Data = iolist()</v> <v>Timeout = timeout()</v> - <v>Reason = term()</v> </type> <desc> - <p>Deletes the file specified by <c><![CDATA[Name]]></c>, like - <c><![CDATA[file:delete/1]]></c></p> + <p>Writes <c><![CDATA[data]]></c> to the file referenced by <c><![CDATA[Handle]]></c>. + The file is to be opened with <c><![CDATA[write]]></c> or <c><![CDATA[append]]></c> + flag. Returns <c><![CDATA[ok]]></c> if successful or <c><![CDATA[{error, reason()}]]></c> + otherwise.</p> </desc> </func> + <func> - <name>make_dir(ChannelPid, Name) -> </name> - <name>make_dir(ChannelPid, Name, Timeout) -> ok | {error, Reason}</name> - <fsummary>Create a directory</fsummary> + <name>write_file(ChannelPid, File, Iolist) -></name> + <name>write_file(ChannelPid, File, Iolist, Timeout) -> ok | {error, reason()}</name> + <fsummary>Writes a file.</fsummary> <type> <v>ChannelPid = pid()</v> - <v>Name = string()</v> + <v>File = string()</v> + <v>Iolist = iolist()</v> <v>Timeout = timeout()</v> - <v>Reason = term()</v> </type> <desc> - <p>Creates a directory specified by <c><![CDATA[Name]]></c>. <c><![CDATA[Name]]></c> should - be a full path to a new directory. The directory can only be - created in an existing directory.</p> + <p>Writes a file to the server. The file is created if it does not exist + but overwritten if it exists.</p> </desc> </func> + <func> - <name>del_dir(ChannelPid, Name) -> </name> - <name>del_dir(ChannelPid, Name, Timeout) -> ok | {error, Reason}</name> - <fsummary>Delete an empty directory</fsummary> + <name>write_file_info(ChannelPid, Name, Info) -></name> + <name>write_file_info(ChannelPid, Name, Info, Timeout) -> ok | {error, reason()}</name> + <fsummary>Writes information for a file.</fsummary> <type> <v>ChannelPid = pid()</v> <v>Name = string()</v> + <v>Info = record()</v> <v>Timeout = timeout()</v> - <v>Reason = term()</v> </type> <desc> - <p>Deletes a directory specified by <c><![CDATA[Name]]></c>. The directory - should be empty.</p> + <p>Writes file information from a <c><![CDATA[file_info]]></c> record to the + file specified by <c><![CDATA[Name]]></c>. See + <seealso marker="kernel:file#write_file_info-2">file:write_file_info/[2,3]</seealso> + for information about the record. + </p> </desc> </func> - </funcs> - + </erlref> diff --git a/lib/ssh/doc/src/ssh_sftpd.xml b/lib/ssh/doc/src/ssh_sftpd.xml index b3d64e72b4..1be29b3b29 100644 --- a/lib/ssh/doc/src/ssh_sftpd.xml +++ b/lib/ssh/doc/src/ssh_sftpd.xml @@ -1,91 +1,97 @@ -<?xml version="1.0" encoding="latin1" ?> +<?xml version="1.0" encoding="utf-8" ?> <!DOCTYPE erlref SYSTEM "erlref.dtd"> <erlref> <header> <copyright> - <year>2005</year><year>2010</year> + <year>2005</year><year>2016</year> <holder>Ericsson AB. All Rights Reserved.</holder> </copyright> <legalnotice> - The contents of this file are subject to the Erlang Public License, - Version 1.1, (the "License"); you may not use this file except in - compliance with the License. You should have received a copy of the - Erlang Public License along with this software. If not, it can be - retrieved online at http://www.erlang.org/. + Licensed under the Apache License, Version 2.0 (the "License"); + you may not use this file except in compliance with the License. + You may obtain a copy of the License at + + http://www.apache.org/licenses/LICENSE-2.0 - Software distributed under the License is distributed on an "AS IS" - basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See - the License for the specific language governing rights and limitations - under the License. + Unless required by applicable law or agreed to in writing, software + distributed under the License is distributed on an "AS IS" BASIS, + WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + See the License for the specific language governing permissions and + limitations under the License. </legalnotice> <title>ssh_sftpd</title> - <prepared>Ingela Anderton Andin</prepared> - <responsible></responsible> - <docno>1</docno> - <approved></approved> - <checked></checked> + <prepared></prepared> + <docno></docno> <date>2005-09-22</date> - <rev>PA1</rev> + <rev></rev> <file>ssh_sftpd.sgml</file> </header> <module>ssh_sftpd</module> - <modulesummary>Specifies a channel process to handle a sftp subsystem.</modulesummary> + <modulesummary>Specifies the channel process to handle an SFTP subsystem.</modulesummary> <description> - <p>Specifies a channel process to handle a sftp subsystem.</p> + <p>Specifies a channel process to handle an SFTP subsystem.</p> </description> <section> - <title>COMMON DATA TYPES </title> - <p><c>subsystem_spec() = {subsystem_name(), {channel_callback(), channel_init_args()}} </c></p> - <p><c>subsystem_name() = "sftp"</c></p> - <p><c>channel_callback() = atom()</c> - Name of the erlang module implementing the - subsystem using the ssh_channel behavior see - <seealso marker="ssh_channel">ssh_channel(3)</seealso></p> - <p><c> channel_init_args() = list() - The one given as argument to function - subsystem_spec/1.</c></p> + <title>DATA TYPES</title> + <taglist> + <tag><c>subsystem_spec() =</c></tag> + <item><p><c>{subsystem_name(), {channel_callback(), channel_init_args()}}</c></p></item> + <tag><c>subsystem_name() =</c></tag> + <item><p><c>"sftp"</c></p></item> + <tag><c>channel_callback() =</c></tag> + <item><p><c>atom()</c> - Name of the Erlang module implementing the subsystem using the + <c>ssh_channel</c> behavior, see the + <seealso marker="ssh_channel">ssh_channel(3)</seealso> manual page.</p></item> + <tag><c>channel_init_args() =</c></tag> + <item><p><c>list()</c> - The one given as argument to function <c>subsystem_spec/1</c>.</p></item> + </taglist> </section> <funcs> <func> <name>subsystem_spec(Options) -> subsystem_spec()</name> - <fsummary>Returns the subsystem specification that allows an ssh daemon to handle the subsystem "sftp".</fsummary> + <fsummary>Returns the subsystem specification that allows an SSH daemon to handle the subsystem "sftp".</fsummary> <type> <v>Options = [{Option, Value}]</v> </type> <desc> - <p>Should be used together with ssh:daemon/[1,2,3]</p> - <p>Options are:</p> + <p>Is to be used together with <c>ssh:daemon/[1,2,3]</c></p> + <p>Options:</p> <taglist> <tag><c><![CDATA[{cwd, String}]]></c></tag> <item> - <p>Sets the initial current working directory for the - server.</p> + <p>Sets the initial current working directory for the server.</p> </item> <tag><c><![CDATA[{file_handler, CallbackModule}]]></c></tag> <item> - <p>Determines which module to call for communicating with - the file server. Default value is <c>ssh_sftpd_file</c> that uses the - file and filelib API:s to access the standard OTP file - server. This option may be used to plug in the use of - other file servers.</p> - </item> - <tag><c><![CDATA[{max_files, Integer}]]></c></tag> - <item> - <p>The default value is <c>0</c>, which means that there is no upper limit. - If supplied, the number of filenames returned to the sftp client per <c>READDIR</c> - request, is limited to at most the given value.</p> - </item> + <p>Determines which module to call for accessing + the file server. The default value is <c>ssh_sftpd_file</c>, which uses the + <seealso marker="kernel:file">file</seealso> and <seealso marker="stdlib:filelib">filelib</seealso> + APIs to access the standard OTP file server. This option can be used to plug in + other file servers.</p> + </item> + <tag><c><![CDATA[{max_files, Integer}]]></c></tag> + <item> + <p>The default value is <c>0</c>, which means that there is no upper limit. + If supplied, the number of filenames returned to the SFTP client per <c>READDIR</c> + request is limited to at most the given value.</p> + </item> <tag><c><![CDATA[{root, String}]]></c></tag> <item> - <p>Sets the sftp root directory. The user will then not be - able to see any files above this root. If for instance - the root is set to <c>/tmp</c> the user will see this - directory as <c>/</c> and if the user does cd <c>/etc</c> - the user will end up in <c>/tmp/etc</c>. + <p>Sets the SFTP root directory. Then the user cannot see any files + above this root. If, for example, the root directory is set to <c>/tmp</c>, + then the user sees this directory as <c>/</c>. If the user then writes + <c>cd /etc</c>, the user moves to <c>/tmp/etc</c>. </p> </item> + <tag><c><![CDATA[{sftpd_vsn, integer()}]]></c></tag> + <item> + <p>Sets the SFTP version to use. Defaults to 5. Version 6 is under + development and limited.</p> + </item> </taglist> </desc> </func> diff --git a/lib/ssh/doc/src/user_guide.gif b/lib/ssh/doc/src/user_guide.gif Binary files differdeleted file mode 100644 index e6275a803d..0000000000 --- a/lib/ssh/doc/src/user_guide.gif +++ /dev/null diff --git a/lib/ssh/doc/src/usersguide.xml b/lib/ssh/doc/src/usersguide.xml new file mode 100644 index 0000000000..70051ba771 --- /dev/null +++ b/lib/ssh/doc/src/usersguide.xml @@ -0,0 +1,39 @@ +<?xml version="1.0" encoding="utf-8" ?> +<!DOCTYPE part SYSTEM "part.dtd"> + +<part xmlns:xi="http://www.w3.org/2001/XInclude"> + <header> + <copyright> + <year>2012</year><year>2016</year> + <holder>Ericsson AB. All Rights Reserved.</holder> + </copyright> + <legalnotice> + Licensed under the Apache License, Version 2.0 (the "License"); + you may not use this file except in compliance with the License. + You may obtain a copy of the License at + + http://www.apache.org/licenses/LICENSE-2.0 + + Unless required by applicable law or agreed to in writing, software + distributed under the License is distributed on an "AS IS" BASIS, + WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + See the License for the specific language governing permissions and + limitations under the License. + + </legalnotice> + + <title>SSH User's Guide</title> + <prepared>OTP Team</prepared> + <docno></docno> + <date>2012-10-11</date> + <rev></rev> + <file>usersguide.xml</file> + </header> + <description> + <p>The Erlang Secure Shell (SSH) application, <c>ssh</c>, implements the SSH Transport Layer Protocol and + provides SSH File Transfer Protocol (SFTP) clients and servers. + </p> + </description> + <xi:include href="introduction.xml"/> + <xi:include href="using_ssh.xml"/> +</part> diff --git a/lib/ssh/doc/src/using_ssh.xml b/lib/ssh/doc/src/using_ssh.xml new file mode 100644 index 0000000000..0861c641c7 --- /dev/null +++ b/lib/ssh/doc/src/using_ssh.xml @@ -0,0 +1,390 @@ +<?xml version="1.0" encoding="utf-8" ?> +<!DOCTYPE chapter SYSTEM "chapter.dtd"> + +<chapter> + <header> + <copyright> + <year>2012</year> + <year>2016</year> + <holder>Ericsson AB. All Rights Reserved.</holder> + </copyright> + <legalnotice> + Licensed under the Apache License, Version 2.0 (the "License"); + you may not use this file except in compliance with the License. + You may obtain a copy of the License at + + http://www.apache.org/licenses/LICENSE-2.0 + + Unless required by applicable law or agreed to in writing, software + distributed under the License is distributed on an "AS IS" BASIS, + WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + See the License for the specific language governing permissions and + limitations under the License. + + </legalnotice> + + <title>Getting Started</title> + <prepared></prepared> + <docno></docno> + <approved></approved> + <date></date> + <rev></rev> + <file>using_ssh.xml</file> + </header> + + <section> + <title>General Information</title> + <p>The following examples use the utility function + <seealso marker="ssh#start-0"> ssh:start/0</seealso> to start + all needed applications (<c>crypto</c>, <c>public_key</c>, and <c>ssh</c>). + All examples are run in an Erlang shell, or in a bash shell, using <em>openssh</em> + to illustrate how the <c>ssh</c> application can be used. The + examples are run as the user <c>otptest</c> on a local network where the + user is authorized to log in over <c>ssh</c> to the host <em>tarlop</em>. + </p> + <p>If nothing else is stated, it is presumed that the <c>otptest</c> user + has an entry in the <em>authorized_keys</em> file of <em>tarlop</em> + (allowed to log in over <c>ssh</c> without entering a password). + Also, <em>tarlop</em> is a known host in the <c>known_hosts</c> + file of the user <c>otptest</c>. This means that host-verification + can be done without user-interaction. + </p> + </section> + + <section> + <title>Using the Erlang ssh Terminal Client</title> + + <p>The user <c>otptest</c>, which has bash as default shell, uses the + <c>ssh:shell/1</c> client to connect to the <em>openssh</em> daemon running on a + host called <em>tarlop</em>:</p> + + <code type="erl" > + 1> ssh:start(). + ok + 2> {ok, S} = ssh:shell("tarlop"). + otptest@tarlop:> pwd + /home/otptest + otptest@tarlop:> exit + logout + 3> + </code> + </section> + + <section> + <marker id="Running an Erlang ssh Daemon"></marker> + <title>Running an Erlang ssh Daemon</title> + + <p>The <c>system_dir</c> option must be a directory containing a host + key file and it defaults to <c>/etc/ssh</c>. For details, see Section + Configuration Files in <seealso + marker="SSH_app">ssh(6)</seealso>. + </p> + + <note><p>Normally, the <c>/etc/ssh</c> directory is only readable by root.</p> + </note> + + <p>The option <c>user_dir</c> defaults to directory <c>users ~/.ssh</c>.</p> + + <p><em>Step 1.</em> To run the example without root privileges, + generate new keys and host keys:</p> + + <code> + $bash> ssh-keygen -t rsa -f /tmp/ssh_daemon/ssh_host_rsa_key + [...] + $bash> ssh-keygen -t rsa -f /tmp/otptest_user/.ssh/id_rsa + [...] + </code> + + <p><em>Step 2.</em> Create the file <c>/tmp/otptest_user/.ssh/authorized_keys</c> + and add the content of <c>/tmp/otptest_user/.ssh/id_rsa.pub</c>.</p> + + <p><em>Step 3.</em> Start the Erlang <c>ssh</c> daemon:</p> + + <code type="erl"> + 1> ssh:start(). + ok + 2> {ok, Sshd} = ssh:daemon(8989, [{system_dir, "/tmp/ssh_daemon"}, + {user_dir, "/tmp/otptest_user/.ssh"}]). + {ok,<0.54.0>} + 3> + </code> + + <p><em>Step 4.</em> Use the <em>openssh</em> client from a shell to connect + to the Erlang <c>ssh</c> daemon:</p> + + <code> + $bash> ssh tarlop -p 8989 -i /tmp/otptest_user/.ssh/id_rsa\ + -o UserKnownHostsFile=/tmp/otptest_user/.ssh/known_hosts + The authenticity of host 'tarlop' can't be established. + RSA key fingerprint is 14:81:80:50:b1:1f:57:dd:93:a8:2d:2f:dd:90:ae:a8. + Are you sure you want to continue connecting (yes/no)? yes + Warning: Permanently added 'tarlop' (RSA) to the list of known hosts. + Eshell V5.10 (abort with ^G) + 1> + </code> + + <p>There are two ways of shutting down an <c>ssh</c> daemon, + see <em>Step 5a</em> and <em>Step 5b</em>.</p> + + <p><em>Step 5a.</em> Shut down the Erlang <c>ssh</c> daemon so that it + stops the listener but leaves existing connections, started by the listener, + operational:</p> + + <code type="erl"> + 3> ssh:stop_listener(Sshd). + ok + 4> + </code> + + <p><em>Step 5b.</em> Shut down the Erlang <c>ssh</c> daemon so that it + stops the listener and all connections started by the listener:</p> + + <code type="erl"> + 3> ssh:stop_daemon(Sshd) + ok + 4> + </code> + + </section> + + <section> + <title>One-Time Execution</title> + + <p>In the following example, the Erlang shell is the client process + that receives the channel replies.</p> + + <note><p>The number of received messages in this example depends on which OS + and which shell that is used on the machine running the <c>ssh</c> daemon. + See also <seealso marker="ssh_connection#exec-4">ssh_connection:exec/4</seealso>. + </p></note> + + <p>Do a one-time execution of a remote command over <c>ssh</c>:</p> + + <code type="erl" > + 1> ssh:start(). + ok + 2> {ok, ConnectionRef} = ssh:connect("tarlop", 22, []). + {ok,<0.57.0>} + 3>{ok, ChannelId} = ssh_connection:session_channel(ConnectionRef, infinity). + {ok,0} + 4> success = ssh_connection:exec(ConnectionRef, ChannelId, "pwd", infinity). + 5> flush(). + Shell got {ssh_cm,<0.57.0>,{data,0,0,<<"/home/otptest\n">>}} + Shell got {ssh_cm,<0.57.0>,{eof,0}} + Shell got {ssh_cm,<0.57.0>,{exit_status,0,0}} + Shell got {ssh_cm,<0.57.0>,{closed,0}} + ok + 6> + </code> + + <p>Notice that only the channel is closed. The connection is still up and can + handle other channels:</p> + + <code type="erl" > + 6> {ok, NewChannelId} = ssh_connection:session_channel(ConnectionRef, infinity). + {ok,1} + ... + </code> + </section> + + <section> + <title>SFTP Server</title> + + <p>Start the Erlang <c>ssh</c> daemon with the SFTP subsystem:</p> + + <code type="erl" > + 1> ssh:start(). + ok + 2> ssh:daemon(8989, [{system_dir, "/tmp/ssh_daemon"}, + {user_dir, "/tmp/otptest_user/.ssh"}, + {subsystems, [ssh_sftpd:subsystem_spec([{cwd, "/tmp/sftp/example"}]) + ]}]). + {ok,<0.54.0>} + 3> + </code> + + <p>Run the OpenSSH SFTP client:</p> + + <code type="erl"> + $bash> sftp -oPort=8989 -o IdentityFile=/tmp/otptest_user/.ssh/id_rsa\ + -o UserKnownHostsFile=/tmp/otptest_user/.ssh/known_hosts tarlop + Connecting to tarlop... + sftp> pwd + Remote working directory: /tmp/sftp/example + sftp> + </code> + </section> + + <section> + <title>SFTP Client</title> + + <p>Fetch a file with the Erlang SFTP client:</p> + + <code type="erl" > + 1> ssh:start(). + ok + 2> {ok, ChannelPid, Connection} = ssh_sftp:start_channel("tarlop", []). + {ok,<0.57.0>,<0.51.0>} + 3> ssh_sftp:read_file(ChannelPid, "/home/otptest/test.txt"). + {ok,<<"This is a test file\n">>} + </code> + </section> + + <section> + <title>SFTP Client with TAR Compression and Encryption</title> + + <p>Example of writing and then reading a tar file follows:</p> + <code type="erl"> + {ok,HandleWrite} = ssh_sftp:open_tar(ChannelPid, ?tar_file_name, [write]), + ok = erl_tar:add(HandleWrite, .... ), + ok = erl_tar:add(HandleWrite, .... ), + ... + ok = erl_tar:add(HandleWrite, .... ), + ok = erl_tar:close(HandleWrite), + + %% And for reading + {ok,HandleRead} = ssh_sftp:open_tar(ChannelPid, ?tar_file_name, [read]), + {ok,NameValueList} = erl_tar:extract(HandleRead,[memory]), + ok = erl_tar:close(HandleRead), + </code> + + <p>The previous write and read example can be extended with encryption and decryption as follows:</p> + <code type="erl"> +%% First three parameters depending on which crypto type we select: +Key = <<"This is a 256 bit key. abcdefghi">>, +Ivec0 = crypto:strong_rand_bytes(16), +DataSize = 1024, % DataSize rem 16 = 0 for aes_cbc + +%% Initialization of the CryptoState, in this case it is the Ivector. +InitFun = fun() -> {ok, Ivec0, DataSize} end, + +%% How to encrypt: +EncryptFun = + fun(PlainBin,Ivec) -> + EncryptedBin = crypto:block_encrypt(aes_cbc256, Key, Ivec, PlainBin), + {ok, EncryptedBin, crypto:next_iv(aes_cbc,EncryptedBin)} + end, + +%% What to do with the very last block: +CloseFun = + fun(PlainBin, Ivec) -> + EncryptedBin = crypto:block_encrypt(aes_cbc256, Key, Ivec, + pad(16,PlainBin) %% Last chunk + ), + {ok, EncryptedBin} + end, + +Cw = {InitFun,EncryptFun,CloseFun}, +{ok,HandleWrite} = ssh_sftp:open_tar(ChannelPid, ?tar_file_name, [write,{crypto,Cw}]), +ok = erl_tar:add(HandleWrite, .... ), +ok = erl_tar:add(HandleWrite, .... ), +... +ok = erl_tar:add(HandleWrite, .... ), +ok = erl_tar:close(HandleWrite), + +%% And for decryption (in this crypto example we could use the same InitFun +%% as for encryption): +DecryptFun = + fun(EncryptedBin,Ivec) -> + PlainBin = crypto:block_decrypt(aes_cbc256, Key, Ivec, EncryptedBin), + {ok, PlainBin, crypto:next_iv(aes_cbc,EncryptedBin)} + end, + +Cr = {InitFun,DecryptFun}, +{ok,HandleRead} = ssh_sftp:open_tar(ChannelPid, ?tar_file_name, [read,{crypto,Cw}]), +{ok,NameValueList} = erl_tar:extract(HandleRead,[memory]), +ok = erl_tar:close(HandleRead), + </code> + </section> + + <section> + <title>Creating a Subsystem</title> + + <p>A small <c>ssh</c> subsystem that echoes N bytes can be implemented as shown + in the following example:</p> + + <code type="erl" > +-module(ssh_echo_server). +-behaviour(ssh_subsystem). +-record(state, { + n, + id, + cm + }). +-export([init/1, handle_msg/2, handle_ssh_msg/2, terminate/2]). + +init([N]) -> + {ok, #state{n = N}}. + +handle_msg({ssh_channel_up, ChannelId, ConnectionManager}, State) -> + {ok, State#state{id = ChannelId, + cm = ConnectionManager}}. + +handle_ssh_msg({ssh_cm, CM, {data, ChannelId, 0, Data}}, #state{n = N} = State) -> + M = N - size(Data), + case M > 0 of + true -> + ssh_connection:send(CM, ChannelId, Data), + {ok, State#state{n = M}}; + false -> + <<SendData:N/binary, _/binary>> = Data, + ssh_connection:send(CM, ChannelId, SendData), + ssh_connection:send_eof(CM, ChannelId), + {stop, ChannelId, State} + end; +handle_ssh_msg({ssh_cm, _ConnectionManager, + {data, _ChannelId, 1, Data}}, State) -> + error_logger:format(standard_error, " ~p~n", [binary_to_list(Data)]), + {ok, State}; + +handle_ssh_msg({ssh_cm, _ConnectionManager, {eof, _ChannelId}}, State) -> + {ok, State}; + +handle_ssh_msg({ssh_cm, _, {signal, _, _}}, State) -> + %% Ignore signals according to RFC 4254 section 6.9. + {ok, State}; + +handle_ssh_msg({ssh_cm, _, {exit_signal, ChannelId, _, _Error, _}}, + State) -> + {stop, ChannelId, State}; + +handle_ssh_msg({ssh_cm, _, {exit_status, ChannelId, _Status}}, State) -> + {stop, ChannelId, State}. + +terminate(_Reason, _State) -> + ok. + </code> + + <p>The subsystem can be run on the host <em>tarlop</em> with the generated keys, + as described in Section <seealso marker="#Running an Erlang ssh Daemon"> + Running an Erlang ssh Daemon</seealso>:</p> + + <code type="erl" > + 1> ssh:start(). + ok + 2> ssh:daemon(8989, [{system_dir, "/tmp/ssh_daemon"}, + {user_dir, "/tmp/otptest_user/.ssh"} + {subsystems, [{"echo_n", {ssh_echo_server, [10]}}]}]). + {ok,<0.54.0>} + 3> + </code> + + <code type="erl" > + 1> ssh:start(). + ok + 2>{ok, ConnectionRef} = ssh:connect("tarlop", 8989, [{user_dir, "/tmp/otptest_user/.ssh"}]). + {ok,<0.57.0>} + 3>{ok, ChannelId} = ssh_connection:session_channel(ConnectionRef, infinity). + 4> success = ssh_connection:subsystem(ConnectionRef, ChannelId, "echo_n", infinity). + 5> ok = ssh_connection:send(ConnectionRef, ChannelId, "0123456789", infinity). + 6> flush(). + {ssh_msg, <0.57.0>, {data, 0, 1, "0123456789"}} + {ssh_msg, <0.57.0>, {eof, 0}} + {ssh_msg, <0.57.0>, {closed, 0}} + 7> {error, closed} = ssh_connection:send(ConnectionRef, ChannelId, "10", infinity). + </code> +<p>See also <seealso marker="ssh_channel"> ssh_channel(3)</seealso>.</p> + +</section> + +</chapter> |
