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diff --git a/lib/ssl/doc/src/ssl.xml b/lib/ssl/doc/src/ssl.xml index 0c042f8571..e831f73530 100644 --- a/lib/ssl/doc/src/ssl.xml +++ b/lib/ssl/doc/src/ssl.xml @@ -8,254 +8,277 @@ <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>ssl</title> + <prepared></prepared> + <docno></docno> + <date></date> + <rev></rev> <file>ssl.xml</file> </header> <module>ssl</module> <modulesummary>Interface Functions for Secure Socket Layer</modulesummary> <description> - <p>This module contains interface functions to the Secure Socket - Layer. + <p> + This module contains interface functions for the SSL/TLS protocol. + For detailed information about the supported standards see + <seealso marker="ssl_app">ssl(6)</seealso>. </p> </description> - + <section> - <title>SSL</title> + <title>DATA TYPES</title> + <p>The following data types are used in the functions for SSL:</p> - <list type="bulleted"> - <item>ssl requires the crypto and public_key applications.</item> - <item>Supported SSL/TLS-versions are SSL-3.0, TLS-1.0, - TLS-1.1 and TLS-1.2.</item> - <item>For security reasons sslv2 is not supported.</item> - <item>Ephemeral Diffie-Hellman cipher suites are supported - but not Diffie Hellman Certificates cipher suites.</item> - <item>Elliptic Curve cipher suites are supported if crypto - supports it and named curves are used. + <taglist> + + <tag><c>boolean() =</c></tag> + <item><p><c>true | false</c></p></item> + + <tag><c>option() =</c></tag> + <item><p><c>socketoption() | ssloption() | transportoption()</c></p> </item> - <item>Export cipher suites are not supported as the - U.S. lifted its export restrictions in early 2000.</item> - <item>IDEA cipher suites are not supported as they have - become deprecated by the latest TLS spec so there is not any - real motivation to implement them.</item> - <item>CRL and policy certificate extensions are not supported - yet. However CRL verification is supported by public_key, only not integrated - in ssl yet. </item> - <item>Support for 'Server Name Indication' extension client side - (RFC 6066 section 3).</item> - </list> - - </section> - - <section> - <title>COMMON DATA TYPES</title> - <p>The following data types are used in the functions below: - </p> - <p><c>boolean() = true | false</c></p> + <tag><c>socketoption() =</c></tag> + <item><p><c>proplists:property()</c></p> + <p>The default socket options are + <c>[{mode,list},{packet, 0},{header, 0},{active, true}]</c>.</p> + <p>For valid options, see the + <seealso marker="kernel:inet">inet(3)</seealso> and + <seealso marker="kernel:gen_tcp">gen_tcp(3)</seealso> manual pages + in Kernel.</p></item> - <p><c>option() = socketoption() | ssloption() | transportoption()</c></p> + <tag><marker id="type-ssloption"/><c>ssloption() =</c></tag> + <item> + <p><c>{verify, verify_type()}</c></p> + <p><c>| {verify_fun, {fun(), term()}}</c></p> + <p><c>| {fail_if_no_peer_cert, boolean()}</c></p> + <p><c>| {depth, integer()}</c></p> + <p><c>| {cert, public_key:der_encoded()}</c></p> + <p><c>| {certfile, path()}</c></p> + <p><c>| {key, {'RSAPrivateKey'| 'DSAPrivateKey' | 'ECPrivateKey' + | 'PrivateKeyInfo', public_key:der_encoded()}}</c></p> + <p><c>| {keyfile, path()}</c></p> + <p><c>| {password, string()}</c></p> + <p><c>| {cacerts, [public_key:der_encoded()]}</c></p> + <p><c>| {cacertfile, path()}</c></p> + <p><c>| {dh, public_key:der_encoded()}</c></p> + <p><c>| {dhfile, path()}</c></p> + <p><c>| {ciphers, ciphers()}</c></p> + <p><c>| {user_lookup_fun, {fun(), term()}}, {psk_identity, string()}, + {srp_identity, {string(), string()}}</c></p> + <p><c>| {reuse_sessions, boolean()}</c></p> + <p><c>| {reuse_session, fun()} {next_protocols_advertised, [binary()]}</c></p> + <p><c>| {client_preferred_next_protocols, {client | server, + [binary()]} | {client | server, [binary()], binary()}}</c></p> + <p><c>| {log_alert, boolean()}</c></p> + <p><c>| {server_name_indication, hostname() | disable}</c></p> + <p><c>| {sni_hosts, [{hostname(), ssloptions()}]}</c></p> + <p><c>| {sni_fun, SNIfun::fun()}</c></p> + </item> + + <tag><c>transportoption() =</c></tag> + <item><p><c>{cb_info, {CallbackModule::atom(), DataTag::atom(), + + ClosedTag::atom(), ErrTag:atom()}}</c></p> + <p>Defaults to <c>{gen_tcp, tcp, tcp_closed, tcp_error}</c>. Can be used + to customize the transport layer. The callback module must implement a + reliable transport protocol, behave as <c>gen_tcp</c>, and have functions + corresponding to <c>inet:setopts/2</c>, <c>inet:getopts/2</c>, + <c>inet:peername/1</c>, <c>inet:sockname/1</c>, and <c>inet:port/1</c>. + The callback <c>gen_tcp</c> is treated specially and calls <c>inet</c> + directly.</p> + <taglist> + <tag><c>CallbackModule =</c></tag> + <item><p><c>atom()</c></p></item> + <tag><c>DataTag =</c></tag> + <item><p><c>atom()</c></p> + <p>Used in socket data message.</p></item> + <tag><c>ClosedTag =</c></tag> + <item><p><c>atom()</c></p> + <p>Used in socket close message.</p></item> + </taglist> + </item> - <p><c>socketoption() = proplists:property() - The default socket options are - [{mode,list},{packet, 0},{header, 0},{active, true}]. - </c></p> + <tag><c>verify_type() =</c></tag> + <item><p><c>verify_none | verify_peer</c></p></item> - <p>For valid options - see <seealso marker="kernel:inet">inet(3)</seealso> and - <seealso marker="kernel:gen_tcp">gen_tcp(3)</seealso>. - </p> - - <p><marker id="type-ssloption"></marker><c>ssloption() = {verify, verify_type()} | - {verify_fun, {fun(), term()}} | - {fail_if_no_peer_cert, boolean()} - {depth, integer()} | - {cert, der_encoded()}| {certfile, path()} | - {key, {'RSAPrivateKey'| 'DSAPrivateKey' | 'ECPrivateKey' |'PrivateKeyInfo', der_encoded()}} | - {keyfile, path()} | {password, string()} | - {cacerts, [der_encoded()]} | {cacertfile, path()} | - |{dh, der_encoded()} | {dhfile, path()} | {ciphers, ciphers()} | - {user_lookup_fun, {fun(), term()}}, {psk_identity, string()}, {srp_identity, {string(), string()}} | - {ssl_imp, ssl_imp()} | {reuse_sessions, boolean()} | {reuse_session, fun()} - {next_protocols_advertised, [binary()]} | - {client_preferred_next_protocols, {client | server, [binary()]} | {client | server, [binary()], binary()}} | - {log_alert, boolean()} | {server_name_indication, hostname() | disable} - </c></p> - - <p><c>transportoption() = {cb_info, {CallbackModule::atom(), DataTag::atom(), ClosedTag::atom(), ErrTag:atom()}} - - defaults to {gen_tcp, tcp, tcp_closed, tcp_error}. Can be used to customize - the transport layer. The callback module must implement a reliable transport - protocol and behave as gen_tcp and in addition have functions corresponding to - inet:setopts/2, inet:getopts/2, inet:peername/1, inet:sockname/1 and inet:port/1. - The callback gen_tcp is treated specially and will call inet directly. - </c></p> - - <p><c> CallbackModule = - atom()</c> - </p> <p><c> DataTag = - atom() - tag used in socket data message.</c></p> - <p><c> ClosedTag = atom() - tag used in - socket close message.</c></p> - - <p><c>verify_type() = verify_none | verify_peer</c></p> - - <p><c>path() = string() - representing a file path.</c></p> + <tag><c>path() =</c></tag> + <item><p><c>string()</c></p> + <p>Represents a file path.</p></item> - <p><c>der_encoded() = binary() -Asn1 DER encoded entity as an erlang binary.</c></p> - - <p><c>host() = hostname() | ipaddress()</c></p> - - <p><c>hostname() = string()</c></p> - - <p><c> - ip_address() = {N1,N2,N3,N4} % IPv4 - | {K1,K2,K3,K4,K5,K6,K7,K8} % IPv6 </c></p> + <tag><c>public_key:der_encoded() =</c></tag> + <item><p><c>binary()</c></p> + <p>ASN.1 DER-encoded entity as an Erlang binary.</p></item> - <p><c>sslsocket() - opaque to the user. </c></p> - - <p><c>protocol() = sslv3 | tlsv1 | 'tlsv1.1' | 'tlsv1.2' </c></p> - - <p><c>ciphers() = [ciphersuite()] | string() (according to old API)</c></p> - - <p><c>ciphersuite() = - {key_exchange(), cipher(), hash()}</c></p> - - <p><c>key_exchange() = rsa | dhe_dss | dhe_rsa | dh_anon - | psk | dhe_psk | rsa_psk | srp_anon | srp_dss | srp_rsa - | ecdh_anon | ecdh_ecdsa | ecdhe_ecdsa | ecdh_rsa | ecdhe_rsa - </c></p> + <tag><c>host() =</c></tag> + <item><p><c>hostname() | ipaddress()</c></p></item> + + <tag><c>hostname() =</c></tag> + <item><p><c>string()</c></p></item> + + <tag><c>ip_address() =</c></tag> + <item><p><c>{N1,N2,N3,N4} % IPv4 | {K1,K2,K3,K4,K5,K6,K7,K8} % IPv6 + </c></p></item> + + <tag><c>sslsocket() =</c></tag> + <item><p>opaque()</p></item> + + <tag><marker id="type-protocol"/><c>protocol() =</c></tag> + <item><p><c>sslv3 | tlsv1 | 'tlsv1.1' | 'tlsv1.2'</c></p></item> + + <tag><c>ciphers() =</c></tag> + <item><p><c>= [ciphersuite()] | string()</c></p> + <p>According to old API.</p></item> + + <tag><c>ciphersuite() =</c></tag> + + <item><p><c>{key_exchange(), cipher(), MAC::hash()} | + {key_exchange(), cipher(), MAC::hash(), PRF::hash()}</c></p></item> + + <tag><c>key_exchange()=</c></tag> + <item><p><c>rsa | dhe_dss | dhe_rsa | dh_anon | psk | dhe_psk + | rsa_psk | srp_anon | srp_dss | srp_rsa | ecdh_anon | ecdh_ecdsa + | ecdhe_ecdsa | ecdh_rsa | ecdhe_rsa</c></p></item> + + <tag><c>cipher() =</c></tag> + <item><p><c>rc4_128 | des_cbc | '3des_ede_cbc' + | aes_128_cbc | aes_256_cbc | aes_128_gcm | aes_256_gcm</c></p></item> - <p><c>cipher() = rc4_128 | des_cbc | '3des_ede_cbc' - | aes_128_cbc | aes_256_cbc </c></p> + <tag><c>hash() =</c></tag> + <item><p><c>md5 | sha | sha224 | sha256 | sha348 | sha512</c></p></item> - <p> <c>hash() = md5 | sha - </c></p> + <tag><c>prf_random() =</c></tag> + <item><p><c>client_random | server_random</c></p></item> - <p><c>prf_random() = client_random | server_random - </c></p> + <tag><c>srp_param_type() =</c></tag> + <item><p><c>srp_1024 | srp_1536 | srp_2048 | srp_3072 + | srp_4096 | srp_6144 | srp_8192</c></p></item> - <p><c>srp_param_type() = srp_1024 | srp_1536 | srp_2048 | srp_3072 - | srp_4096 | srp_6144 | srp_8192</c></p> + <tag><c>SNIfun::fun()</c></tag> + <item><p><c>= fun(ServerName :: string()) -> ssloptions()</c></p></item> + </taglist> </section> <section> <title>SSL OPTION DESCRIPTIONS - COMMON for SERVER and CLIENT</title> - <p>Options described here are options that are have the same - meaning in the client and the server. - </p> + <p>The following options have the same meaning in the client and + the server:</p> <taglist> - <tag>{cert, der_encoded()}</tag> - <item> The DER encoded users certificate. If this option - is supplied it will override the certfile option.</item> + <tag><c>{cert, public_key:der_encoded()}</c></tag> + <item><p>The DER-encoded users certificate. If this option + is supplied, it overrides option <c>certfile</c>.</p></item> - <tag>{certfile, path()}</tag> - <item>Path to a file containing the user's PEM encoded certificate.</item> + <tag><c>{certfile, path()}</c></tag> + <item><p>Path to a file containing the user certificate.</p></item> - <tag>{key, {'RSAPrivateKey'| 'DSAPrivateKey' | 'ECPrivateKey' |'PrivateKeyInfo', der_encoded()}}</tag> - <item> The DER encoded users private key. If this option - is supplied it will override the keyfile option.</item> + <tag><c>{key, {'RSAPrivateKey'| 'DSAPrivateKey' | 'ECPrivateKey' + |'PrivateKeyInfo', public_key:der_encoded()}}</c></tag> + <item><p>The DER-encoded user's private key. If this option + is supplied, it overrides option <c>keyfile</c>.</p></item> - <tag>{keyfile, path()}</tag> - <item>Path to file containing user's - private PEM encoded key. As PEM-files may contain several - entries this option defaults to the same file as given by - certfile option.</item> - - <tag>{password, string()}</tag> - <item>String containing the user's password. - Only used if the private keyfile is password protected. - </item> - - <tag>{cacerts, [der_encoded()]}</tag> - <item> The DER encoded trusted certificates. If this option - is supplied it will override the cacertfile option.</item> - - <tag>{ciphers, ciphers()}</tag> - <item>The cipher suites that should be supported. The function + <tag><c>{keyfile, path()}</c></tag> + <item><p>Path to the file containing the user's + private PEM-encoded key. As PEM-files can contain several + entries, this option defaults to the same file as given by + option <c>certfile</c>.</p></item> + + <tag><c>{password, string()}</c></tag> + <item><p>String containing the user's password. Only used if the + private keyfile is password-protected.</p></item> + + <tag><c>{ciphers, ciphers()}</c></tag> + <item><p>Supported cipher suites. The function <c>cipher_suites/0</c> can be used to find all ciphers that are - supported by default. <c>cipher_suites(all)</c> may be called - to find all available cipher suites. - Pre-Shared Key (<url href="http://www.ietf.org/rfc/rfc4279.txt">RFC 4279</url> and + supported by default. <c>cipher_suites(all)</c> can be called + to find all available cipher suites. Pre-Shared Key + (<url href="http://www.ietf.org/rfc/rfc4279.txt">RFC 4279</url> and <url href="http://www.ietf.org/rfc/rfc5487.txt">RFC 5487</url>), - Secure Remote Password (<url href="http://www.ietf.org/rfc/rfc5054.txt">RFC 5054</url>) + Secure Remote Password + (<url href="http://www.ietf.org/rfc/rfc5054.txt">RFC 5054</url>), RC4 cipher suites, and anonymous cipher suites only work if explicitly enabled by - this option and they are supported/enabled by the peer also. - Note that anonymous cipher suites are supported for testing purposes - only and should not be used when security matters. - </item> - - <tag>{ssl_imp, new | old}</tag> - <item>No longer has any meaning as the old implementation has - been removed, it will be ignored. - </item> - - <tag>{secure_renegotiate, boolean()}</tag> - <item>Specifies if to reject renegotiation attempt that does - not live up to <url href="http://www.ietf.org/rfc/rfc5746.txt">RFC 5746</url>. By default secure_renegotiate is - set to false i.e. secure renegotiation will be used if possible - but it will fallback to unsecure renegotiation if the peer - does not support <url href="http://www.ietf.org/rfc/rfc5746.txt">RFC 5746</url>. + this option; they are supported/enabled by the peer also. + Anonymous cipher suites are supported for testing purposes + only and are not be used when security matters.</p></item> + + <tag><c>{secure_renegotiate, boolean()}</c></tag> + <item><p>Specifies if to reject renegotiation attempt that does + not live up to + <url href="http://www.ietf.org/rfc/rfc5746.txt">RFC 5746</url>. + By default <c>secure_renegotiate</c> is set to <c>false</c>, + that is, secure renegotiation is used if possible, + but it falls back to insecure renegotiation if the peer + does not support + <url href="http://www.ietf.org/rfc/rfc5746.txt">RFC 5746</url>.</p> </item> - <tag>{depth, integer()}</tag> - <item> - The depth is the maximum number of non-self-issued - intermediate certificates that may follow the peer certificate - in a valid certification path. So if depth is 0 the PEER must - be signed by the trusted ROOT-CA directly, if 1 the path can - be PEER, CA, ROOT-CA, if it is 2 PEER, CA, CA, ROOT-CA and so - on. The default value is 1. - </item> + <tag><c>{depth, integer()}</c></tag> + <item><p>Maximum number of non-self-issued + intermediate certificates that can follow the peer certificate + in a valid certification path. So, if depth is 0 the PEER must + be signed by the trusted ROOT-CA directly; if 1 the path can + be PEER, CA, ROOT-CA; if 2 the path can be PEER, CA, CA, + ROOT-CA, and so on. The default value is 1.</p></item> - <tag>{verify_fun, {Verifyfun :: fun(), InitialUserState :: term()}}</tag> - <item> - <p>The verification fun should be defined as:</p> + <tag><c>{verify_fun, {Verifyfun :: fun(), InitialUserState :: + term()}}</c></tag> + <item><p>The verification fun is to be defined as follows:</p> <code> -fun(OtpCert :: #'OTPCertificate'{}, Event :: {bad_cert, Reason :: atom() | {revoked, atom()}} | +fun(OtpCert :: #'OTPCertificate'{}, Event :: {bad_cert, Reason :: atom() | {revoked, +atom()}} | {extension, #'Extension'{}}, InitialUserState :: term()) -> {valid, UserState :: term()} | {valid_peer, UserState :: term()} | {fail, Reason :: term()} | {unknown, UserState :: term()}. </code> - <p>The verify fun will be called during the X509-path - validation when an error or an extension unknown to the ssl - application is encountered. Additionally it will be called + <p>The verification fun is called during the X509-path + validation when an error or an extension unknown to the SSL + application is encountered. It is also called when a certificate is considered valid by the path validation to allow access to each certificate in the path to the user - application. Note that it will differentiate between the - peer certificate and CA certificates by using valid_peer or - valid as the second argument to the verify fun. See <seealso - marker="public_key:cert_records">the public_key User's - Guide</seealso> for definition of #'OTPCertificate'{} and - #'Extension'{}.</p> - - <p>If the verify callback fun returns {fail, Reason}, the - verification process is immediately stopped and an alert is - sent to the peer and the TLS/SSL handshake is terminated. If - the verify callback fun returns {valid, UserState}, the - verification process is continued. If the verify callback fun - always returns {valid, UserState}, the TLS/SSL handshake will - not be terminated with respect to verification failures and - the connection will be established. If called with an - extension unknown to the user application, the return value - {unknown, UserState} should be used.</p> - - <p>The default verify_fun option in verify_peer mode:</p> + application. It differentiates between the peer + certificate and the CA certificates by using <c>valid_peer</c> or + <c>valid</c> as second argument to the verification fun. See the + <seealso marker="public_key:public_key_records">public_key User's + Guide</seealso> for definition of <c>#'OTPCertificate'{}</c> and + <c>#'Extension'{}</c>.</p> + + <list type="bulleted"> + <item><p>If the verify callback fun returns <c>{fail, Reason}</c>, + the verification process is immediately stopped, an alert is + sent to the peer, and the TLS/SSL handshake terminates.</p></item> + <item><p>If the verify callback fun returns <c>{valid, UserState}</c>, + the verification process continues.</p></item> + <item><p>If the verify callback fun always returns + <c>{valid, UserState}</c>, the TLS/SSL handshake does not + terminate regarding verification failures and the connection is + established.</p></item> + <item><p>If called with an extension unknown to the user application, + return value <c>{unknown, UserState}</c> is to be used.</p> + + <p>Note that if the fun returns <c>unknown</c> for an extension marked + as critical, validation will fail.</p> + </item> + </list> + + <p>Default option <c>verify_fun</c> in <c>verify_peer mode</c>:</p> <code> {fun(_,{bad_cert, _} = Reason, _) -> @@ -269,11 +292,13 @@ fun(OtpCert :: #'OTPCertificate'{}, Event :: {bad_cert, Reason :: atom() | {revo end, []} </code> - <p>The default verify_fun option in verify_none mode:</p> + <p>Default option <c>verify_fun</c> in mode <c>verify_none</c>:</p> <code> {fun(_,{bad_cert, _}, UserState) -> {valid, UserState}; + (_,{extension, #'Extension'{critical = true}}, UserState) -> + {valid, UserState}; (_,{extension, _}, UserState) -> {unknown, UserState}; (_, valid, UserState) -> @@ -283,49 +308,88 @@ fun(OtpCert :: #'OTPCertificate'{}, Event :: {bad_cert, Reason :: atom() | {revo end, []} </code> - <p>Possible path validation errors are given on the form {bad_cert, Reason} where Reason is:</p> + <p>The possible path validation errors are given on form + <c>{bad_cert, Reason}</c> where <c>Reason</c> is:</p> <taglist> - <tag>unknown_ca</tag> - <item>No trusted CA was found in the trusted store. The trusted CA is - normally a so called ROOT CA that is a self-signed cert. Trust may - be claimed for an intermediat CA (trusted anchor does not have to be self signed - according to X-509) by using the option <c>partial_chain</c></item> - - <tag>selfsigned_peer</tag> - <item>The chain consisted only of one self-signed certificate.</item> - - <tag>PKIX X-509-path validation error</tag> - <item> Possible such reasons see <seealso - marker="public_key:public_key#pkix_path_validation-3"> public_key:pkix_path_validation/3 </seealso></item> + <tag><c>unknown_ca</c></tag> + <item><p>No trusted CA was found in the trusted store. The trusted CA is + normally a so called ROOT CA, which is a self-signed certificate. Trust can + be claimed for an intermediate CA (trusted anchor does not have to be + self-signed according to X-509) by using option <c>partial_chain</c>.</p> + </item> + + <tag><c>selfsigned_peer</c></tag> + <item><p>The chain consisted only of one self-signed certificate.</p></item> + + <tag><c>PKIX X-509-path validation error</c></tag> + <item><p>For possible reasons, see <seealso +marker="public_key:public_key#pkix_path_validation-3">public_key:pkix_path_validation/3</seealso> + </p></item> </taglist> - </item> - <tag>{partial_chain, fun(Chain::[DerCert]) -> {trusted_ca, DerCert} | unknown_ca </tag> + <tag><c>{crl_check, boolean() | peer | best_effort }</c></tag> <item> - Claim an intermediat CA in the chain as trusted. TLS will then perform the public_key:pkix_path_validation/3 - with the selected CA as trusted anchor and the rest of the chain. - </item> + Perform CRL (Certificate Revocation List) verification + <seealso marker="public_key:public_key#pkix_crls_validate-3"> + (public_key:pkix_crls_validate/3)</seealso> on all the certificates during the path validation + <seealso + marker="public_key:public_key#pkix_path_validation-3">(public_key:pkix_path_validation/3) + </seealso> + of the certificate chain. Defaults to false. + + <p><c>peer</c> - check is only performed on + the peer certificate.</p> - <tag>{versions, [protocol()]}</tag> - <item>TLS protocol versions that will be supported by started clients and servers. - This option overrides the application environment option <c>protocol_version</c>. If the - environment option is not set it defaults to all versions supported by the SSL application. See also - <seealso marker="ssl:ssl_app">ssl(6)</seealso> - </item> + <p><c>best_effort</c> - if certificate revocation status can not be determined + it will be accepted as valid.</p> - <tag>{hibernate_after, integer()|undefined}</tag> - <item>When an integer-value is specified, the <c>ssl_connection</c> - will go into hibernation after the specified number of milliseconds - of inactivity, thus reducing its memory footprint. When - <c>undefined</c> is specified (this is the default), the process - will never go into hibernation. + <p>The CA certificates specified for the connection will be used to + construct the certificate chain validating the CRLs.</p> + + <p>The CRLs will be fetched from a local or external cache see + <seealso marker="ssl:ssl_crl_cache_api">ssl_crl_cache_api(3)</seealso>.</p> </item> - <tag>{user_lookup_fun, {Lookupfun :: fun(), UserState :: term()}}</tag> + <tag><c>{crl_cache, {Module :: atom(), {DbHandle :: internal | term(), Args :: list()}}}</c></tag> <item> - <p>The lookup fun should be defined as:</p> + <p>Module defaults to ssl_crl_cache with <c> DbHandle </c> internal and an + empty argument list. The following arguments may be specified for the internal cache.</p> + <taglist> + <tag><c>{http, timeout()}</c></tag> + <item><p> + Enables fetching of CRLs specified as http URIs in<seealso + marker="public_key:public_key_records"> X509 certificate extensions.</seealso> + Requires the OTP inets application.</p> + </item> + </taglist> + </item> + + <tag><c>{partial_chain, fun(Chain::[DerCert]) -> {trusted_ca, DerCert} | + unknown_ca }</c></tag> + <item><p>Claim an intermediate CA in the chain as trusted. TLS then + performs <seealso + marker="public_key:public_key#pkix_path_validation-3">public_key:pkix_path_validation/3</seealso> + with the selected CA as trusted anchor and the rest of the chain.</p></item> + + <tag><c>{versions, [protocol()]}</c></tag> + <item><p>TLS protocol versions supported by started clients and servers. + This option overrides the application environment option + <c>protocol_version</c>. If the environment option is not set, it defaults + to all versions, except SSL-3.0, supported by the SSL application. + See also <seealso marker="ssl:ssl_app">ssl(6).</seealso></p></item> + + <tag><c>{hibernate_after, integer()|undefined}</c></tag> + <item><p>When an integer-value is specified, <c>ssl_connection</c> + goes into hibernation after the specified number of milliseconds + of inactivity, thus reducing its memory footprint. When + <c>undefined</c> is specified (this is the default), the process + never goes into hibernation.</p></item> + + <tag><c>{user_lookup_fun, {Lookupfun :: fun(), UserState :: term()}}</c></tag> + <item><p>The lookup fun is to defined as follows:</p> + <code> fun(psk, PSKIdentity ::string(), UserState :: term()) -> {ok, SharedSecret :: binary()} | error; @@ -333,104 +397,120 @@ fun(srp, Username :: string(), UserState :: term()) -> {ok, {SRPParams :: srp_param_type(), Salt :: binary(), DerivedKey :: binary()}} | error. </code> - <p>For Pre-Shared Key (PSK) cipher suites, the lookup fun will - be called by the client and server to determine the shared - secret. When called by the client, PSKIdentity will be set to the - hint presented by the server or undefined. When called by the - server, PSKIdentity is the identity presented by the client. - </p> - - <p>For Secure Remote Password (SRP), the fun will only be used by the server to obtain - parameters that it will use to generate its session keys. <c>DerivedKey</c> should be - derived according to <url href="http://tools.ietf.org/html/rfc2945#section-3"> RFC 2945</url> and - <url href="http://tools.ietf.org/html/rfc5054#section-2.4"> RFC 5054</url>: - <c>crypto:sha([Salt, crypto:sha([Username, <<$:>>, Password])]) </c> + <p>For Pre-Shared Key (PSK) cipher suites, the lookup fun is + called by the client and server to determine the shared + secret. When called by the client, <c>PSKIdentity</c> is set to the + hint presented by the server or to undefined. When called by the + server, <c>PSKIdentity</c> is the identity presented by the client.</p> + + <p>For Secure Remote Password (SRP), the fun is only used by the server to + obtain parameters that it uses to generate its session keys. + <c>DerivedKey</c> is to be derived according to + <url href="http://tools.ietf.org/html/rfc2945#section-3"> RFC 2945</url> and + <url href="http://tools.ietf.org/html/rfc5054#section-2.4"> RFC 5054</url>: + <c>crypto:sha([Salt, crypto:sha([Username, <<$:>>, Password])])</c> </p> </item> - <tag>{padding_check, boolean()}</tag> - <item> - <p> This option only affects TLS-1.0 connections. - If set to false it disables the block cipher padding check - to be able to interoperate with legacy software. - </p> - - <warning><p> Using this option makes TLS vulnerable to - the Poodle attack</p></warning> - - </item> - + <tag><c>{padding_check, boolean()}</c></tag> + <item><p>Affects TLS-1.0 connections only. + If set to <c>false</c>, it disables the block cipher padding check + to be able to interoperate with legacy software.</p></item> + </taglist> - + + <warning><p>Using <c>{padding_check, boolean()}</c> makes TLS + vulnerable to the Poodle attack.</p></warning> </section> <section> <title>SSL OPTION DESCRIPTIONS - CLIENT SIDE</title> - <p>Options described here are client specific or has a slightly different - meaning in the client than in the server.</p> + <p>The following options are client-specific or have a slightly different + meaning in the client than in the server:</p> <taglist> - <tag>{verify, verify_type()}</tag> - <item> In verify_none mode the default behavior will be to - allow all x509-path validation errors. See also the verify_fun - option. - </item> - <tag>{reuse_sessions, boolean()}</tag> - <item>Specifies if client should try to reuse sessions - when possible. + + <tag><c>{verify, verify_type()}</c></tag> + <item><p>In mode <c>verify_none</c> the default behavior is to allow + all x509-path validation errors. See also option <c>verify_fun</c>.</p> </item> + + <tag><c>{reuse_sessions, boolean()}</c></tag> + <item><p>Specifies if the client is to try to reuse sessions + when possible.</p></item> + + <tag><c>{cacerts, [public_key:der_encoded()]}</c></tag> + <item><p>The DER-encoded trusted certificates. If this option + is supplied it overrides option <c>cacertfile</c>.</p></item> - <tag>{cacertfile, path()}</tag> - <item>The path to a file containing PEM encoded CA certificates. The CA + <tag><c>{cacertfile, path()}</c></tag> + <item><p>Path to a file containing PEM-encoded CA certificates. The CA certificates are used during server authentication and when building the - client certificate chain. - </item> - - <tag>{client_preferred_next_protocols, {Precedence :: server | client, ClientPrefs :: [binary()]}}</tag> - <tag>{client_preferred_next_protocols, {Precedence :: server | client, ClientPrefs :: [binary()], Default :: binary()}}</tag> + client certificate chain.</p> + </item> + + <tag><c>{alpn_advertised_protocols, [binary()]}</c></tag> + <item> + <p>The list of protocols supported by the client to be sent to the + server to be used for an Application-Layer Protocol Negotiation (ALPN). + If the server supports ALPN then it will choose a protocol from this + list; otherwise it will fail the connection with a "no_application_protocol" + alert. A server that does not support ALPN will ignore this value.</p> + + <p>The list of protocols must not contain an empty binary.</p> + + <p>The negotiated protocol can be retrieved using the <c>negotiated_protocol/1</c> function.</p> + </item> + + <tag><c>{client_preferred_next_protocols, {Precedence :: server | client, ClientPrefs :: [binary()]}}</c><br/> + <c>{client_preferred_next_protocols, {Precedence :: server | client, ClientPrefs :: [binary()], Default :: binary()}}</c></tag> <item> - <p>Indicates the client will try to perform Next Protocol + <p>Indicates that the client is to try to perform Next Protocol Negotiation.</p> - <p>If precedence is server the negotiated protocol will be the - first protocol that appears on the server advertised list that is + <p>If precedence is server, the negotiated protocol is the + first protocol to be shown on the server advertised list, which is also on the client preference list.</p> - <p>If precedence is client the negotiated protocol will be the - first protocol that appears on the client preference list that is + <p>If precedence is client, the negotiated protocol is the + first protocol to be shown on the client preference list, which is also on the server advertised list.</p> <p>If the client does not support any of the server advertised - protocols or the server does not advertise any protocols the - client will fallback to the first protocol in its list or if a - default is supplied it will fallback to that instead. If the - server does not support Next Protocol Negotiation the - connection will be aborted if no default protocol is supplied.</p> + protocols or the server does not advertise any protocols, the + client falls back to the first protocol in its list or to the + default protocol (if a default is supplied). If the + server does not support Next Protocol Negotiation, the + connection terminates if no default protocol is supplied.</p> </item> - <tag>{psk_identity, string()}</tag> - <item>Specifies the identity the client presents to the server. The matching secret is - found by calling the user_look_fun. - </item> - <tag>{srp_identity, {Username :: string(), Password :: string()}</tag> - <item>Specifies the Username and Password to use to authenticate to the server. + <tag><c>{psk_identity, string()}</c></tag> + <item><p>Specifies the identity the client presents to the server. + The matching secret is found by calling <c>user_lookup_fun</c>.</p> </item> - <tag>{server_name_indication, hostname()}</tag> - <tag>{server_name_indication, disable}</tag> + + <tag><c>{srp_identity, {Username :: string(), Password :: string()} + </c></tag> + <item><p>Specifies the username and password to use to authenticate + to the server.</p></item> + + <tag><c>{server_name_indication, hostname()}</c></tag> + <item><p>Can be specified when upgrading a TCP socket to a TLS + socket to use the TLS Server Name Indication extension.</p></item> + + <tag><c>{server_name_indication, disable}</c></tag> <item> - <p>This option can be specified when upgrading a TCP socket to a TLS - socket to use the TLS Server Name Indication extension.</p> - <p>When starting a TLS connection without upgrade the Server Name - Indication extension will be sent if possible, this option may also be + <p>When starting a TLS connection without upgrade, the Server Name + Indication extension is sent if possible. This option can be used to disable that behavior.</p> </item> - <tag>{fallback, boolean()}</tag> + <tag><c>{fallback, boolean()}</c></tag> <item> <p> Send special cipher suite TLS_FALLBACK_SCSV to avoid undesired TLS version downgrade. Defaults to false</p> <warning><p>Note this option is not needed in normal TLS usage and should not be used - to implement new clients. But legacy clients that that retries connections in the following manner</p> + to implement new clients. But legacy clients that retries connections in the following manner</p> <p><c> ssl:connect(Host, Port, [...{versions, ['tlsv2', 'tlsv1.1', 'tlsv1', 'sslv3']}])</c></p> <p><c> ssl:connect(Host, Port, [...{versions, [tlsv1.1', 'tlsv1', 'sslv3']}, {fallback, true}])</c></p> @@ -441,130 +521,215 @@ fun(srp, Username :: string(), UserState :: term()) -> be supported by the server for the prevention to work. </p></warning> </item> - - </taglist> + <tag><marker id="client_signature_algs"/><c>{signature_algs, [{hash(), ecdsa | rsa | dsa}]}</c></tag> + <item> + <p>In addition to the algorithms negotiated by the cipher + suite used for key exchange, payload encryption, message + authentication and pseudo random calculation, the TLS signature + algorithm extension <url + href="http://www.ietf.org/rfc/rfc5246.txt">Section 7.4.1.4.1 in RFC 5246</url> may be + used, from TLS 1.2, to negotiate which signature algorithm to use during the + TLS handshake. If no lower TLS versions than 1.2 are supported, + the client will send a TLS signature algorithm extension + with the algorithms specified by this option. + Defaults to + + <code>[ +%% SHA2 +{sha512, ecdsa}, +{sha512, rsa}, +{sha384, ecdsa}, +{sha384, rsa}, +{sha256, ecdsa}, +{sha256, rsa}, +{sha224, ecdsa}, +{sha224, rsa}, +%% SHA +{sha, ecdsa}, +{sha, rsa}, +{sha, dsa}, +%% MD5 +{md5, rsa} +]</code> + + The algorithms should be in the preferred order. + Selected signature algorithm can restrict which hash functions + that may be selected. + </p> + </item> + </taglist> </section> - + <section> <title>SSL OPTION DESCRIPTIONS - SERVER SIDE</title> - <p>Options described here are server specific or has a slightly different - meaning in the server than in the client.</p> + <p>The following options are server-specific or have a slightly different + meaning in the server than in the client:</p> <taglist> + + <tag><c>{cacerts, [public_key:der_encoded()]}</c></tag> + <item><p>The DER-encoded trusted certificates. If this option + is supplied it overrides option <c>cacertfile</c>.</p></item> - <tag>{cacertfile, path()}</tag> - <item>The path to a file containing PEM encoded CA + <tag><c>{cacertfile, path()}</c></tag> + <item><p>Path to a file containing PEM-encoded CA certificates. The CA certificates are used to build the server - certificate chain, and for client authentication. Also the CAs - are used in the list of acceptable client CAs passed to the - client when a certificate is requested. May be omitted if there - is no need to verify the client and if there are not any - intermediate CAs for the server certificate. - </item> + certificate chain and for client authentication. The CAs are + also used in the list of acceptable client CAs passed to the + client when a certificate is requested. Can be omitted if there + is no need to verify the client and if there are no + intermediate CAs for the server certificate.</p></item> - <tag>{dh, der_encoded()}</tag> - <item>The DER encoded Diffie Hellman parameters. If this option - is supplied it will override the dhfile option. + <tag><c>{dh, public_key:der_encoded()}</c></tag> + <item><p>The DER-encoded Diffie-Hellman parameters. If specified, + it overrides option <c>dhfile</c>.</p></item> + + <tag><c>{dhfile, path()}</c></tag> + <item><p>Path to a file containing PEM-encoded Diffie Hellman parameters + to be used by the server if a cipher suite using Diffie Hellman key + exchange is negotiated. If not specified, default parameters are used. + </p></item> + + <tag><c>{verify, verify_type()}</c></tag> + <item><p>A server only does x509-path validation in mode <c>verify_peer</c>, + as it then sends a certificate request to the client + (this message is not sent if the verify option is <c>verify_none</c>). + You can then also want to specify option <c>fail_if_no_peer_cert</c>. + </p></item> + + <tag><c>{fail_if_no_peer_cert, boolean()}</c></tag> + <item><p>Used together with <c>{verify, verify_peer}</c> by an SSL server. + If set to <c>true</c>, the server fails if the client does not have + a certificate to send, that is, sends an empty certificate. If set to + <c>false</c>, it fails only if the client sends an invalid + certificate (an empty certificate is considered valid). Defaults to false.</p> </item> - <tag>{dhfile, path()}</tag> - <item>Path to file containing PEM encoded Diffie Hellman parameters, - for the server to use if a cipher suite using Diffie Hellman key exchange - is negotiated. If not specified default parameters will be used. - </item> - - <tag>{verify, verify_type()}</tag> - <item>Servers only do the x509-path validation in verify_peer - mode, as it then will send a certificate request to the client - (this message is not sent if the verify option is verify_none) - and you may then also want to specify the option - fail_if_no_peer_cert. - </item> + <tag><c>{reuse_sessions, boolean()}</c></tag> + <item><p>Specifies if the server is to agree to reuse sessions + when requested by the clients. See also option <c>reuse_session</c>. + </p></item> + + <tag><c>{reuse_session, fun(SuggestedSessionId, + PeerCert, Compression, CipherSuite) -> boolean()}</c></tag> + <item><p>Enables the SSL server to have a local policy + for deciding if a session is to be reused or not. + Meaningful only if <c>reuse_sessions</c> is set to <c>true</c>. + <c>SuggestedSessionId</c> is a <c>binary()</c>, <c>PeerCert</c> is + a DER-encoded certificate, <c>Compression</c> is an enumeration integer, + and <c>CipherSuite</c> is of type <c>ciphersuite()</c>.</p></item> + + <tag><c>{alpn_preferred_protocols, [binary()]}</c></tag> + <item> + <p>Indicates the server will try to perform Application-Layer + Protocol Negotiation (ALPN).</p> - <tag>{fail_if_no_peer_cert, boolean()}</tag> - <item>Used together with {verify, verify_peer} by an ssl server. - If set to true, the server will fail if the client does not have - a certificate to send, i.e. sends a empty certificate, if set to - false it will only fail if the client sends an invalid - certificate (an empty certificate is considered valid). - </item> + <p>The list of protocols is in order of preference. The protocol + negotiated will be the first in the list that matches one of the + protocols advertised by the client. If no protocol matches, the + server will fail the connection with a "no_application_protocol" alert.</p> - <tag>{reuse_sessions, boolean()}</tag> - <item>Specifies if the server should agree to reuse sessions - when the clients request to do so. See also the reuse_session - option. + <p>The negotiated protocol can be retrieved using the <c>negotiated_protocol/1</c> function.</p> </item> - <tag>{reuse_session, fun(SuggestedSessionId, - PeerCert, Compression, CipherSuite) -> boolean()}</tag> - <item>Enables the ssl server to have a local policy - for deciding if a session should be reused or not, - only meaningful if <c>reuse_sessions</c> is set to true. - SuggestedSessionId is a binary(), PeerCert is a DER encoded - certificate, Compression is an enumeration integer - and CipherSuite is of type ciphersuite(). - </item> - - <tag>{next_protocols_advertised, Protocols :: [binary()]}</tag> - <item>The list of protocols to send to the client if the client indicates - it supports the Next Protocol extension. The client may select a protocol + <tag><c>{next_protocols_advertised, Protocols :: [binary()]}</c></tag> + <item><p>List of protocols to send to the client if the client indicates that + it supports the Next Protocol extension. The client can select a protocol that is not on this list. The list of protocols must not contain an empty - binary. If the server negotiates a Next Protocol it can be accessed - using <c>negotiated_next_protocol/1</c> method. + binary. If the server negotiates a Next Protocol, it can be accessed + using the <c>negotiated_next_protocol/1</c> method.</p></item> + + <tag><c>{psk_identity, string()}</c></tag> + <item><p>Specifies the server identity hint, which the server presents to + the client.</p></item> + + <tag><c>{log_alert, boolean()}</c></tag> + <item><p>If set to <c>false</c>, error reports are not displayed.</p></item> + + <tag><c>{honor_cipher_order, boolean()}</c></tag> + <item><p>If set to <c>true</c>, use the server preference for cipher + selection. If set to <c>false</c> (the default), use the client + preference.</p></item> + + <tag><c>{sni_hosts, [{hostname(), ssloptions()}]}</c></tag> + <item><p>If the server receives a SNI (Server Name Indication) from the client + matching a host listed in the <c>sni_hosts</c> option, the specific options for + that host will override previously specified options. + + The option <c>sni_fun</c>, and <c>sni_hosts</c> are mutually exclusive.</p></item> + + <tag><c>{sni_fun, SNIfun::fun()}</c></tag> + <item><p>If the server receives a SNI (Server Name Indication) from the client, + the given function will be called to retrieve <c>ssloptions()</c> for the indicated server. + These options will be merged into predefined <c>ssloptions()</c>. + + The function should be defined as: + <c>fun(ServerName :: string()) -> ssloptions()</c> + and can be specified as a fun or as named <c>fun module:function/1</c> + + The option <c>sni_fun</c>, and <c>sni_hosts</c> are mutually exclusive.</p></item> + + <tag><c>{client_renegotiation, boolean()}</c></tag> + <item>In protocols that support client-initiated renegotiation, the cost + of resources of such an operation is higher for the server than the + client. This can act as a vector for denial of service attacks. The SSL + application already takes measures to counter-act such attempts, + but client-initiated renegotiation can be strictly disabled by setting + this option to <c>false</c>. The default value is <c>true</c>. + Note that disabling renegotiation can result in long-lived connections + becoming unusable due to limits on the number of messages the underlying + cipher suite can encipher. </item> - <tag>{psk_identity, string()}</tag> - <item>Specifies the server identity hint the server presents to the client. - </item> - <tag>{log_alert, boolean()}</tag> - <item>If false, error reports will not be displayed.</item> - <tag>{honor_cipher_order, boolean()}</tag> + <tag><c>{honor_cipher_order, boolean()}</c></tag> <item>If true, use the server's preference for cipher selection. If false (the default), use the client's preference. </item> + + <tag><c>{signature_algs, [{hash(), ecdsa | rsa | dsa}]}</c></tag> + <item><p> The algorithms specified by + this option will be the ones accepted by the server in a signature algorithm + negotiation, introduced in TLS-1.2. The algorithms will also be offered to the client if a + client certificate is requested. For more details see the <seealso marker="#client_signature_algs">corresponding client option</seealso>. + </p> </item> + </taglist> </section> <section> <title>General</title> - <p>When an ssl socket is in active mode (the default), data from the + <p>When an SSL socket is in active mode (the default), data from the socket is delivered to the owner of the socket in the form of - messages: - </p> + messages:</p> + <list type="bulleted"> - <item>{ssl, Socket, Data} - </item> - <item>{ssl_closed, Socket} - </item> - <item> - {ssl_error, Socket, Reason} - </item> + <item><p><c>{ssl, Socket, Data}</c></p></item> + <item><p><c>{ssl_closed, Socket}</c></p></item> + <item><p><c>{ssl_error, Socket, Reason}</c></p></item> </list> - - <p>A <c>Timeout</c> argument specifies a timeout in milliseconds. The - default value for a <c>Timeout</c> argument is <c>infinity</c>. - </p> + + <p>A <c>Timeout</c> argument specifies a time-out in milliseconds. The + default value for argument <c>Timeout</c> is <c>infinity</c>.</p> </section> <funcs> <func> <name>cipher_suites() -></name> <name>cipher_suites(Type) -> ciphers()</name> - <fsummary> Returns a list of supported cipher suites</fsummary> + <fsummary>Returns a list of supported cipher suites.</fsummary> <type> <v>Type = erlang | openssl | all</v> - </type> <desc><p>Returns a list of supported cipher suites. - cipher_suites() is equivalent to cipher_suites(erlang). - Type openssl is provided for backwards compatibility with - old ssl that used openssl. cipher_suites(all) returns + <c>cipher_suites()</c> is equivalent to <c>cipher_suites(erlang).</c> + Type <c>openssl</c> is provided for backwards compatibility with the + old SSL, which used OpenSSL. <c>cipher_suites(all)</c> returns all available cipher suites. The cipher suites not present - in cipher_suites(erlang) but in included in cipher_suites(all) - will not be used unless explicitly configured by the user. - </p> + in <c>cipher_suites(erlang)</c> but included in + <c>cipher_suites(all)</c> are not used unless explicitly configured + by the user.</p> </desc> </func> @@ -584,17 +749,17 @@ fun(srp, Username :: string(), UserState :: term()) -> <name>connect(Socket, SslOptions) -> </name> <name>connect(Socket, SslOptions, Timeout) -> {ok, SslSocket} | {error, Reason}</name> - <fsummary> Upgrades a gen_tcp, or - equivalent, connected socket to an ssl socket. </fsummary> + <fsummary>Upgrades a <c>gen_tcp</c>, or + equivalent, connected socket to an SSL socket.</fsummary> <type> - <v>Socket = socket()</v> - <v>SslOptions = [ssloption()]</v> + <v>Socket = socket()</v> + <v>SslOptions = [ssloption()]</v> <v>Timeout = integer() | infinity</v> <v>SslSocket = sslsocket()</v> <v>Reason = term()</v> </type> - <desc> <p>Upgrades a gen_tcp, or equivalent, - connected socket to an ssl socket i.e. performs the + <desc><p>Upgrades a <c>gen_tcp</c>, or equivalent, + connected socket to an SSL socket, that is, performs the client-side ssl handshake.</p> </desc> </func> @@ -603,7 +768,7 @@ fun(srp, Username :: string(), UserState :: term()) -> <name>connect(Host, Port, Options) -></name> <name>connect(Host, Port, Options, Timeout) -> {ok, SslSocket} | {error, Reason}</name> - <fsummary>Opens an ssl connection to Host, Port. </fsummary> + <fsummary>Opens an SSL connection to <c>Host</c>, <c>Port</c>.</fsummary> <type> <v>Host = host()</v> <v>Port = integer()</v> @@ -612,72 +777,107 @@ fun(srp, Username :: string(), UserState :: term()) -> <v>SslSocket = sslsocket()</v> <v>Reason = term()</v> </type> - <desc> <p>Opens an ssl connection to Host, Port.</p> </desc> + <desc><p>Opens an SSL connection to <c>Host</c>, <c>Port</c>.</p></desc> </func> <func> <name>close(SslSocket) -> ok | {error, Reason}</name> - <fsummary>Close an ssl connection</fsummary> + <fsummary>Closes an SSL connection.</fsummary> <type> <v>SslSocket = sslsocket()</v> <v>Reason = term()</v> </type> - <desc><p>Close an ssl connection.</p> + <desc><p>Closes an SSL connection.</p> </desc> </func> <func> + <name>close(SslSocket, How) -> ok | {ok, port()} | {error, Reason}</name> + <fsummary>Closes an SSL connection.</fsummary> + <type> + <v>SslSocket = sslsocket()</v> + <v>How = timeout() | {NewController::pid(), timeout()} </v> + <v>Reason = term()</v> + </type> + <desc><p>Closes or downgrades an SSL connection. In the latter case the transport + connection will be handed over to the <c>NewController</c> process after receiving + the TLS close alert from the peer. The returned transport socket will have + the following options set: <c>[{active, false}, {packet, 0}, {mode, binary}]</c></p> + </desc> + </func> + + <func> <name>controlling_process(SslSocket, NewOwner) -> ok | {error, Reason}</name> - <fsummary>Assigns a new controlling process to the - ssl-socket.</fsummary> - + SSL socket.</fsummary> <type> <v>SslSocket = sslsocket()</v> <v>NewOwner = pid()</v> <v>Reason = term()</v> </type> - <desc><p>Assigns a new controlling process to the ssl-socket. A - controlling process is the owner of an ssl-socket, and receives - all messages from the socket.</p> + <desc><p>Assigns a new controlling process to the SSL socket. A + controlling process is the owner of an SSL socket, and receives + all messages from the socket.</p> </desc> </func> <func> - <name>connection_info(SslSocket) -> - {ok, {ProtocolVersion, CipherSuite}} | {error, Reason} </name> - <fsummary>Returns the negotiated protocol version and cipher suite. + <name>connection_information(SslSocket) -> + {ok, Result} | {error, Reason} </name> + <fsummary>Returns all the connection information. </fsummary> <type> - <v>CipherSuite = ciphersuite()</v> - <v>ProtocolVersion = protocol()</v> + <v>Item = protocol | cipher_suite | sni_hostname | atom()</v> + <d>Meaningful atoms, not specified above, are the ssl option names.</d> + <v>Result = [{Item::atom(), Value::term()}]</v> + <v>Reason = term()</v> </type> - <desc><p>Returns the negotiated protocol version and cipher suite.</p> + <desc><p>Returns all relevant information about the connection, ssl options that + are undefined will be filtered out.</p> </desc> </func> - <func> + <func> + <name>connection_information(SslSocket, Items) -> + {ok, Result} | {error, Reason} </name> + <fsummary>Returns the requested connection information. + </fsummary> + <type> + <v>Items = [Item]</v> + <v>Item = protocol | cipher_suite | sni_hostname | atom()</v> + <d>Meaningful atoms, not specified above, are the ssl option names.</d> + <v>Result = [{Item::atom(), Value::term()}]</v> + <v>Reason = term()</v> + </type> + <desc><p>Returns the requested information items about the connection, + if they are defined.</p> + <note><p>If only undefined options are requested the + resulting list can be empty.</p></note> + </desc> + </func> + + <func> <name>format_error(Reason) -> string()</name> - <fsummary>Return an error string.</fsummary> + <fsummary>Returns an error string.</fsummary> <type> <v>Reason = term()</v> </type> <desc> - <p>Presents the error returned by an ssl function as a printable string.</p> + <p>Presents the error returned by an SSL function as a printable string.</p> </desc> </func> <func> <name>getopts(Socket, OptionNames) -> {ok, [socketoption()]} | {error, Reason}</name> - <fsummary>Get the value of the specified options.</fsummary> + <fsummary>Gets the values of the specified options.</fsummary> <type> <v>Socket = sslsocket()</v> <v>OptionNames = [atom()]</v> </type> <desc> - <p>Get the value of the specified socket options. + <p>Gets the values of the specified socket options. </p> </desc> </func> @@ -685,34 +885,49 @@ fun(srp, Username :: string(), UserState :: term()) -> <func> <name>listen(Port, Options) -> {ok, ListenSocket} | {error, Reason}</name> - <fsummary>Creates an ssl listen socket.</fsummary> + <fsummary>Creates an SSL listen socket.</fsummary> <type> <v>Port = integer()</v> <v>Options = options()</v> <v>ListenSocket = sslsocket()</v> </type> <desc> - <p>Creates an ssl listen socket.</p> + <p>Creates an SSL listen socket.</p> </desc> </func> <func> + <name>negotiated_protocol(Socket) -> {ok, Protocol} | {error, protocol_not_negotiated}</name> + <fsummary>Returns the protocol negotiated through ALPN or NPN extensions.</fsummary> + <type> + <v>Socket = sslsocket()</v> + <v>Protocol = binary()</v> + </type> + <desc> + <p> + Returns the protocol negotiated through ALPN or NPN extensions. + </p> + </desc> + </func> + + <func> <name>peercert(Socket) -> {ok, Cert} | {error, Reason}</name> - <fsummary>Return the peer certificate.</fsummary> + <fsummary>Returns the peer certificate.</fsummary> <type> <v>Socket = sslsocket()</v> <v>Cert = binary()</v> </type> <desc> - <p>The peer certificate is returned as a DER encoded binary. - The certificate can be decoded with <c>public_key:pkix_decode_cert/2</c>. - </p> + <p>The peer certificate is returned as a DER-encoded binary. + The certificate can be decoded with + <c>public_key:pkix_decode_cert/2</c>.</p> </desc> </func> + <func> <name>peername(Socket) -> {ok, {Address, Port}} | {error, Reason}</name> - <fsummary>Return peer address and port.</fsummary> + <fsummary>Returns the peer address and port.</fsummary> <type> <v>Socket = sslsocket()</v> <v>Address = ipaddress()</v> @@ -722,12 +937,32 @@ fun(srp, Username :: string(), UserState :: term()) -> <p>Returns the address and port number of the peer.</p> </desc> </func> + + <func> + <name>prf(Socket, Secret, Label, Seed, WantedLength) -> {ok, binary()} | {error, reason()}</name> + <fsummary>Uses a session Pseudo-Random Function to generate key material.</fsummary> + <type> + <v>Socket = sslsocket()</v> + <v>Secret = binary() | master_secret</v> + <v>Label = binary()</v> + <v>Seed = [binary() | prf_random()]</v> + <v>WantedLength = non_neg_integer()</v> + </type> + <desc> + <p>Uses the Pseudo-Random Function (PRF) of a TLS session to generate + extra key material. It either takes user-generated values for + <c>Secret</c> and <c>Seed</c> or atoms directing it to use a specific + value from the session security parameters.</p> + <p>Can only be used with TLS connections; <c>{error, undefined}</c> + is returned for SSLv3 connections.</p> + </desc> + </func> <func> <name>recv(Socket, Length) -> </name> <name>recv(Socket, Length, Timeout) -> {ok, Data} | {error, Reason}</name> - <fsummary>Receive data on a socket.</fsummary> + <fsummary>Receives data on a socket.</fsummary> <type> <v>Socket = sslsocket()</v> <v>Length = integer()</v> @@ -735,63 +970,43 @@ fun(srp, Username :: string(), UserState :: term()) -> <v>Data = [char()] | binary()</v> </type> <desc> - <p>This function receives a packet from a socket in passive - mode. A closed socket is indicated by a return value + <p>Receives a packet from a socket in passive + mode. A closed socket is indicated by return value <c>{error, closed}</c>.</p> - <p>The <c>Length</c> argument is only meaningful when - the socket is in <c>raw</c> mode and denotes the number of + <p>Argument <c>Length</c> is meaningful only when + the socket is in mode <c>raw</c> and denotes the number of bytes to read. If <c>Length</c> = 0, all available bytes are returned. If <c>Length</c> > 0, exactly <c>Length</c> bytes are returned, or an error; possibly discarding less than <c>Length</c> bytes of data when the socket gets closed from the other side.</p> - <p>The optional <c>Timeout</c> parameter specifies a timeout in + <p>Optional argument <c>Timeout</c> specifies a time-out in milliseconds. The default value is <c>infinity</c>.</p> </desc> </func> <func> - <name>prf(Socket, Secret, Label, Seed, WantedLength) -> {ok, binary()} | {error, reason()}</name> - <fsummary>Use a sessions pseudo random function to generate key material.</fsummary> - <type> - <v>Socket = sslsocket()</v> - <v>Secret = binary() | master_secret</v> - <v>Label = binary()</v> - <v>Seed = [binary() | prf_random()]</v> - <v>WantedLength = non_neg_integer()</v> - </type> - <desc> - <p>Use the pseudo random function (PRF) of a TLS session to generate - additional key material. It either takes user generated values for - <c>Secret</c> and <c>Seed</c> or atoms directing it use a specific - value from the session security parameters.</p> - <p>This function can only be used with TLS connections, <c>{error, undefined}</c> - is returned for SSLv3 connections.</p> - </desc> - </func> - - <func> <name>renegotiate(Socket) -> ok | {error, Reason}</name> - <fsummary> Initiates a new handshake.</fsummary> + <fsummary>Initiates a new handshake.</fsummary> <type> <v>Socket = sslsocket()</v> </type> <desc><p>Initiates a new handshake. A notable return value is <c>{error, renegotiation_rejected}</c> indicating that the peer - refused to go through with the renegotiation but the connection + refused to go through with the renegotiation, but the connection is still active using the previously negotiated session.</p> </desc> </func> <func> <name>send(Socket, Data) -> ok | {error, Reason}</name> - <fsummary>Write data to a socket.</fsummary> + <fsummary>Writes data to a socket.</fsummary> <type> <v>Socket = sslsocket()</v> <v>Data = iodata()</v> </type> <desc> - <p>Writes <c>Data</c> to <c>Socket</c>. </p> + <p>Writes <c>Data</c> to <c>Socket</c>.</p> <p>A notable return value is <c>{error, closed}</c> indicating that the socket is closed.</p> </desc> @@ -799,31 +1014,31 @@ fun(srp, Username :: string(), UserState :: term()) -> <func> <name>setopts(Socket, Options) -> ok | {error, Reason}</name> - <fsummary>Set socket options.</fsummary> + <fsummary>Sets socket options.</fsummary> <type> <v>Socket = sslsocket()</v> <v>Options = [socketoption]()</v> </type> <desc> - <p>Sets options according to <c>Options</c> for the socket - <c>Socket</c>. </p> + <p>Sets options according to <c>Options</c> for socket + <c>Socket</c>.</p> </desc> </func> <func> <name>shutdown(Socket, How) -> ok | {error, Reason}</name> - <fsummary>Immediately close a socket</fsummary> + <fsummary>Immediately closes a socket.</fsummary> <type> <v>Socket = sslsocket()</v> <v>How = read | write | read_write</v> <v>Reason = reason()</v> </type> <desc> - <p>Immediately close a socket in one or two directions.</p> + <p>Immediately closes a socket in one or two directions.</p> <p><c>How == write</c> means closing the socket for writing, reading from it is still possible.</p> <p>To be able to handle that the peer has done a shutdown on - the write side, the <c>{exit_on_close, false}</c> option + the write side, option <c>{exit_on_close, false}</c> is useful.</p> </desc> </func> @@ -831,16 +1046,16 @@ fun(srp, Username :: string(), UserState :: term()) -> <func> <name>ssl_accept(Socket) -> </name> <name>ssl_accept(Socket, Timeout) -> ok | {error, Reason}</name> - <fsummary>Perform server-side SSL/TLS handshake</fsummary> + <fsummary>Performs server-side SSL/TLS handshake.</fsummary> <type> <v>Socket = sslsocket()</v> <v>Timeout = integer()</v> <v>Reason = term()</v> </type> <desc> - <p> Performs the SSL/TLS server-side handshake <c>Socket</c> is a socket as returned - by <seealso - marker="#transport_accept-2">ssl:transport_accept/[1,2]</seealso> + <p>Performs the SSL/TLS server-side handshake.</p> + <p><c>Socket</c> is a socket as returned by + <seealso marker="#transport_accept-2">ssl:transport_accept/[1,2]</seealso> </p> </desc> </func> @@ -848,7 +1063,7 @@ fun(srp, Username :: string(), UserState :: term()) -> <func> <name>ssl_accept(Socket, SslOptions) -> </name> <name>ssl_accept(Socket, SslOptions, Timeout) -> {ok, Socket} | ok | {error, Reason}</name> - <fsummary>Perform server-side SSL/TLS handshake</fsummary> + <fsummary>Performs server-side SSL/TLS handshake.</fsummary> <type> <v>Socket = socket() | sslsocket() </v> <v>SslOptions = ssloptions()</v> @@ -856,17 +1071,19 @@ fun(srp, Username :: string(), UserState :: term()) -> <v>Reason = term()</v> </type> <desc> - <p> If <c>Socket</c> is a socket() - upgrades a gen_tcp, or equivalent, socket to an ssl socket - i.e. performs the SSL/TLS server-side handshake and returns the ssl socket. - </p> + <p>If <c>Socket</c> is a <c>socket()</c>: upgrades a <c>gen_tcp</c>, + or equivalent, socket to an SSL socket, that is, performs + the SSL/TLS server-side handshake and returns the SSL socket.</p> - <warning><p>Note that the listen socket should be in {active, false} mode + <warning><p>The listen socket is to be in mode <c>{active, false}</c> before telling the client that the server is ready to upgrade - by calling this function, otherwise the upgrade may - or may not succeed depending on timing.</p></warning> + by calling this function, else the upgrade succeeds or does not + succeed depending on timing.</p></warning> - <p> If <c>Socket</c> is an sslsocket() - provides additional SSL/TLS options to those specified in <seealso - marker="#listen-2">ssl:listen/2 </seealso> and then performs the SSL/TLS handshake. + <p>If <c>Socket</c> is an <c>sslsocket()</c>: provides extra SSL/TLS + options to those specified in + <seealso marker="#listen-2">ssl:listen/2 </seealso> and then performs + the SSL/TLS handshake. </p> </desc> </func> @@ -874,14 +1091,14 @@ fun(srp, Username :: string(), UserState :: term()) -> <func> <name>sockname(Socket) -> {ok, {Address, Port}} | {error, Reason}</name> - <fsummary>Return the local address and port.</fsummary> + <fsummary>Returns the local address and port.</fsummary> <type> <v>Socket = sslsocket()</v> <v>Address = ipaddress()</v> <v>Port = integer()</v> </type> <desc> - <p>Returns the local address and port number of the socket + <p>Returns the local address and port number of socket <c>Socket</c>.</p> </desc> </func> @@ -889,22 +1106,21 @@ fun(srp, Username :: string(), UserState :: term()) -> <func> <name>start() -> </name> <name>start(Type) -> ok | {error, Reason}</name> - <fsummary>Starts the Ssl application. </fsummary> + <fsummary>Starts the SSL application.</fsummary> <type> - <v>Type = permanent | transient | temporary</v> + <v>Type = permanent | transient | temporary</v> </type> <desc> - <p>Starts the Ssl application. Default type - is temporary. - <seealso marker="kernel:application">application(3)</seealso></p> + <p>Starts the SSL application. Default type + is <c>temporary</c>.</p> </desc> </func> + <func> <name>stop() -> ok </name> - <fsummary>Stops the Ssl application.</fsummary> + <fsummary>Stops the SSL application.</fsummary> <desc> - <p>Stops the Ssl application. - <seealso marker="kernel:application">application(3)</seealso></p> + <p>Stops the SSL application.</p> </desc> </func> @@ -912,8 +1128,8 @@ fun(srp, Username :: string(), UserState :: term()) -> <name>transport_accept(ListenSocket) -></name> <name>transport_accept(ListenSocket, Timeout) -> {ok, NewSocket} | {error, Reason}</name> - <fsummary>Accept an incoming connection and - prepare for <c>ssl_accept</c></fsummary> + <fsummary>Accepts an incoming connection and + prepares for <c>ssl_accept</c>.</fsummary> <type> <v>ListenSocket = NewSocket = sslsocket()</v> <v>Timeout = integer()</v> @@ -922,66 +1138,66 @@ fun(srp, Username :: string(), UserState :: term()) -> <desc> <p>Accepts an incoming connection request on a listen socket. <c>ListenSocket</c> must be a socket returned from - <seealso - marker="#listen-2"> ssl:listen/2</seealso>. - The socket returned should be passed to + <seealso marker="#listen-2"> ssl:listen/2</seealso>. + The socket returned is to be passed to <seealso marker="#ssl_accept-2"> ssl:ssl_accept[2,3]</seealso> - to complete handshaking i.e + to complete handshaking, that is, establishing the SSL/TLS connection.</p> <warning> <p>The socket returned can only be used with - <seealso marker="#ssl_accept-2"> ssl:ssl_accept[2,3]</seealso> - no traffic can be sent or received before that call.</p> + <seealso marker="#ssl_accept-2"> ssl:ssl_accept[2,3]</seealso>. + No traffic can be sent or received before that call.</p> </warning> <p>The accepted socket inherits the options set for - <c>ListenSocket</c> in <seealso - marker="#listen-2"> ssl:listen/2</seealso>.</p> + <c>ListenSocket</c> in + <seealso marker="#listen-2"> ssl:listen/2</seealso>.</p> <p>The default value for <c>Timeout</c> is <c>infinity</c>. If - <c>Timeout</c> is specified, and no connection is accepted + <c>Timeout</c> is specified and no connection is accepted within the given time, <c>{error, timeout}</c> is returned.</p> </desc> </func> <func> - <name>versions() -> - [{SslAppVer, SupportedSslVer, AvailableSslVsn}]</name> + <name>versions() -> [versions_info()]</name> <fsummary>Returns version information relevant for the - ssl application.</fsummary> - <type> - <v>SslAppVer = string()</v> - <v>SupportedSslVer = [protocol()]</v> - <v>AvailableSslVsn = [protocol()]</v> - </type> - <desc> - <p> - Returns version information relevant for the - ssl application.</p> - </desc> - </func> - <func> - <name>negotiated_next_protocol(Socket) -> {ok, Protocol} | {error, next_protocol_not_negotiated}</name> - <fsummary>Returns the Next Protocol negotiated.</fsummary> + SSL application.</fsummary> <type> - <v>Socket = sslsocket()</v> - <v>Protocol = binary()</v> + <v>versions_info() = {app_vsn, string()} | {supported | available, [protocol()] </v> </type> <desc> - <p> - Returns the Next Protocol negotiated. - </p> + <p>Returns version information relevant for the SSL + application.</p> + <taglist> + <tag><c>app_vsn</c></tag> + <item>The application version of the SSL application.</item> + + <tag><c>supported</c></tag> + <item>TLS/SSL versions supported by default. + Overridden by a version option on + <seealso marker="#connect-2"> connect/[2,3,4]</seealso>, + <seealso marker="#listen-2"> listen/2</seealso>, and <seealso + marker="#ssl_accept-2">ssl_accept/[1,2,3]</seealso>. + For the negotiated TLS/SSL version, see <seealso + marker="#connection_information-1">ssl:connection_information/1 + </seealso>.</item> + + <tag><c>available</c></tag> + <item>All TLS/SSL versions supported by the SSL application. + TLS 1.2 requires sufficient support from the Crypto + application.</item> + </taglist> </desc> </func> - + </funcs> <section> <title>SEE ALSO</title> - <p><seealso marker="kernel:inet">inet(3) </seealso> and - <seealso marker="kernel:gen_tcp">gen_tcp(3) </seealso> + <p><seealso marker="kernel:inet">inet(3)</seealso> and + <seealso marker="kernel:gen_tcp">gen_tcp(3)</seealso> </p> </section> </erlref> - |