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-rw-r--r--lib/ssh/doc/src/ssh_app.xml107
1 files changed, 87 insertions, 20 deletions
diff --git a/lib/ssh/doc/src/ssh_app.xml b/lib/ssh/doc/src/ssh_app.xml
index f6ce44c015..e80bb1853d 100644
--- a/lib/ssh/doc/src/ssh_app.xml
+++ b/lib/ssh/doc/src/ssh_app.xml
@@ -4,7 +4,7 @@
<appref>
<header>
<copyright>
- <year>2012</year><year>2015</year>
+ <year>2012</year><year>2018</year>
<holder>Ericsson AB. All Rights Reserved.</holder>
</copyright>
<legalnotice>
@@ -97,7 +97,7 @@
<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>
+ </p>
</section>
<section>
<title>Authorized Keys</title>
@@ -109,7 +109,7 @@
</section>
<section>
<title>Host Keys</title>
- <p>RSA and DSA host keys are supported and are
+ <p>RSA, DSA and ECDSA 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>
@@ -130,33 +130,49 @@
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
+ See the options
+ <seealso marker="ssh:ssh#type-preferred_algorithms_common_option">preferred_algorithms</seealso>
+ and
+ <seealso marker="ssh:ssh#type-modify_algorithms_common_option">modify_algorithms</seealso>
+ 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>
-
+ <p>Supported algorithms are (in the default order):</p>
+ <marker id="supported_algos"></marker>
<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>ecdh-sha2-nistp256</item>
<item>diffie-hellman-group-exchange-sha256</item>
+ <item>diffie-hellman-group16-sha512</item>
+ <item>diffie-hellman-group18-sha512</item>
+ <item>diffie-hellman-group14-sha256</item>
+ <item>curve25519-sha256</item>
+ <item>[email protected]</item>
+ <item>curve448-sha512</item>
<item>diffie-hellman-group14-sha1</item>
- <item>diffie-hellman-group1-sha1</item>
+ <item>diffie-hellman-group-exchange-sha1</item>
+ <item>(diffie-hellman-group1-sha1, retired: It can be enabled with the
+ <seealso marker="ssh:ssh#type-preferred_algorithms_common_option">preferred_algorithms</seealso>
+ or
+ <seealso marker="ssh:ssh#type-modify_algorithms_common_option">modify_algorithms</seealso>
+ options)</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>ecdsa-sha2-nistp256</item>
<item>ssh-rsa</item>
+ <item>rsa-sha2-256</item>
+ <item>rsa-sha2-512</item>
<item>ssh-dss</item>
</list>
</item>
@@ -173,21 +189,24 @@
<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>[email protected]</item>
+ <item>[email protected]</item>
<item>aes256-ctr</item>
+ <item>aes192-ctr</item>
+ <item>[email protected]</item>
+ <item>aes128-ctr</item>
<item>aes128-cbc</item>
<item>3des-cbc</item>
+ <item>(AEAD_AES_128_GCM, not enabled per default)</item>
+ <item>(AEAD_AES_256_GCM, not enabled per default)</item>
</list>
+ <p>See the text at the description of <seealso marker="#rfc5647_note">the rfc 5647 further down</seealso>
+ for more information regarding AEAD_AES_*_GCM.
+ </p>
<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>
@@ -203,7 +222,7 @@
<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 <c>kernel</c> for information about this subject.
+ <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>
@@ -232,7 +251,15 @@
</item>
<item><url href="https://tools.ietf.org/html/rfc4253">RFC 4253</url>, The Secure Shell (SSH) Transport Layer Protocol.
- <p></p>
+ <p>Except</p>
+ <list type="bulleted">
+ <item>8.1. diffie-hellman-group1-sha1. Disabled by default, can be enabled with the
+ <seealso marker="ssh:ssh#type-preferred_algorithms_common_option">preferred_algorithms</seealso>
+ or
+ <seealso marker="ssh:ssh#type-modify_algorithms_common_option">modify_algorithms</seealso>
+ options.</item>
+ </list>
+ <p/>
</item>
<item><url href="https://tools.ietf.org/html/rfc4254">RFC 4254</url>, The Secure Shell (SSH) Connection Protocol.
@@ -269,7 +296,10 @@
<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.
+ they could be enabled with the options
+ <seealso marker="ssh:ssh#type-preferred_algorithms_common_option">preferred_algorithms</seealso>
+ or
+ <seealso marker="ssh:ssh#type-modify_algorithms_common_option">modify_algorithms</seealso>.
</p>
<warning>
<p>
@@ -306,6 +336,43 @@
<p>Comment: Defines hmac-sha2-256 and hmac-sha2-512
</p>
</item>
+
+ <item><url href="https://tools.ietf.org/html/draft-ietf-curdle-ssh-kex-sha2">Draft-ietf-curdle-ssh-kex-sha2 (work in progress)</url>, Key Exchange (KEX) Method Updates and Recommendations for Secure Shell (SSH).
+ <p>Deviations:</p>
+ <list type="bulleted">
+ <item>The <c>diffie-hellman-group1-sha1</c> is not enabled by default, but is still supported and can be enabled
+ with the options
+ <seealso marker="ssh:ssh#type-preferred_algorithms_common_option">preferred_algorithms</seealso>
+ or
+ <seealso marker="ssh:ssh#type-modify_algorithms_common_option">modify_algorithms</seealso>.
+ </item>
+ <item>The questionable sha1-based algorithms <c>diffie-hellman-group-exchange-sha1</c> and
+ <c>diffie-hellman-group14-sha1</c> are still enabled by default for compatibility with ancient clients and servers.
+ They can be disabled with the options
+ <seealso marker="ssh:ssh#type-preferred_algorithms_common_option">preferred_algorithms</seealso>
+ or
+ <seealso marker="ssh:ssh#type-modify_algorithms_common_option">modify_algorithms</seealso>.
+ They will be disabled by default when the draft is turned into an RFC.</item>
+ </list>
+ <p/>
+ </item>
+
+ <item><url href="https://tools.ietf.org/html/rfc8332">RFC 8332</url>, Use of RSA Keys with SHA-256 and SHA-512 in the Secure Shell (SSH) Protocol.
+ </item>
+
+ <item><marker id="supported-ext-info"/>
+ <url href="https://tools.ietf.org/html/rfc8308">RFC 8308</url>, Extension Negotiation in the Secure Shell (SSH) Protocol.
+ <p>Implemented are:</p>
+ <list type="bulleted">
+ <item>The Extension Negotiation Mechanism</item>
+ <item>The extension <c>server-sig-algs</c></item>
+ </list>
+ <p/>
+ </item>
+
+ <item>
+ <url href="https://tools.ietf.org/html/draft-ietf-curdle-ssh-curves">Secure Shell (SSH) Key Exchange Method using Curve25519 and Curve448 (work in progress)</url>
+ </item>
</list>