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diff --git a/lib/ssl/doc/src/ssl.xml b/lib/ssl/doc/src/ssl.xml
index b53344e381..cdf6870c25 100644
--- a/lib/ssl/doc/src/ssl.xml
+++ b/lib/ssl/doc/src/ssl.xml
@@ -4,7 +4,7 @@
<erlref>
<header>
<copyright>
- <year>1999</year><year>2014</year>
+ <year>1999</year><year>2015</year>
<holder>Ericsson AB. All Rights Reserved.</holder>
</copyright>
<legalnotice>
@@ -21,241 +21,272 @@
</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>
+ <p>This module contains interface functions for the SSL.</p>
</description>
<section>
<title>SSL</title>
<list type="bulleted">
- <item>ssl requires the crypto and public_key applications.</item>
+ <item>For application dependencies see <seealso marker="ssl_app"> ssl(6)</seealso> </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
+ TLS-1.1, and TLS-1.2.</item>
+ <item>For security reasons SSL-2.0 is not supported.</item>
+ <item>For security reasons SSL-3.0 is no longer supported by default,
+ but can be configured.</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.
+ <item>Elliptic Curve cipher suites are supported if the Crypto
+ application supports it and named curves are used.
</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>
+ become deprecated by the latest TLS specification so it is not
+ motivated to implement them.</item>
+ <item>CRL validation is supported.</item>
+ <item>Policy certificate extensions are not supported.</item>
+ <item>'Server Name Indication' extension client side
+ (RFC 6066, Section 3) is supported.</item>
</list>
</section>
<section>
- <title>COMMON DATA TYPES</title>
- <p>The following data types are used in the functions below:
- </p>
+ <title>DATA TYPES</title>
+ <p>The following data types are used in the functions for SSL:</p>
- <p><c>boolean() = true | false</c></p>
+ <taglist>
- <p><c>option() = socketoption() | ssloption() | transportoption()</c></p>
+ <tag><c>boolean()</c></tag>
+ <item><p><c>= true | false</c></p></item>
- <p><c>socketoption() = proplists:property() - The default socket options are
- [{mode,list},{packet, 0},{header, 0},{active, true}].
- </c></p>
+ <tag><c>option()</c></tag>
+ <item><p><c>= socketoption() | ssloption() | transportoption()</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>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; CallbackModule =
- atom()</c>
- </p> <p><c>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; DataTag =
- atom() - tag used in socket data message.</c></p>
- <p><c>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 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>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>
+
+ <tag><marker id="type-ssloption"></marker><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()} {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></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>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>verify_type()</c></tag>
+ <item><p><c>= verify_none | verify_peer</c></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>path()</c></tag>
+ <item><p><c>= string()</c></p>
+ <p>Represents a file path.</p></item>
+
+ <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>
+
+ <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 to the user.</p></item>
+
+ <tag><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>
- <p><c>cipher() = rc4_128 | des_cbc | '3des_ede_cbc'
- | aes_128_cbc | aes_256_cbc </c></p>
+ <tag><c>ciphersuite()</c></tag>
+ <item><p><c>= {key_exchange(), cipher(), hash()}</c></p></item>
- <p> <c>hash() = md5 | sha
- </c></p>
+ <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>
- <p><c>prf_random() = client_random | server_random
- </c></p>
+ <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>srp_param_type() = srp_1024 | srp_1536 | srp_2048 | srp_3072
- | srp_4096 | srp_6144 | srp_8192</c></p>
+ <tag><c>hash()</c></tag>
+ <item><p><c>= md5 | sha</c></p></item>
+ <tag><c>prf_random()</c></tag>
+ <item><p><c>= client_random | server_random</c></p></item>
+
+ <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>
+
+ </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 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.
+ 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 fallback to unsecure renegotiation if the peer
+ does not support
+ <url href="http://www.ietf.org/rfc/rfc5746.txt">RFC 5746</url>.</p>
</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>.
- </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>{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>{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:cert_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></item>
+ </list>
+
+ <p>Default option <c>verify_fun</c> in <c>verify_peer mode</c>:</p>
<code>
{fun(_,{bad_cert, _} = Reason, _) ->
@@ -269,7 +300,7 @@ 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) ->
@@ -283,49 +314,88 @@ 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 intermediat 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>
+ Enables fetching of CRLs specified as http URIs in<seealso
+ marker="public_key:cert_records"> X509 cerificate extensions.</seealso>
+ Requires the OTP inets application.
+ </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;
@@ -333,227 +403,294 @@ 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, &lt;&lt;$:&gt;&gt;, Password])]) </c>
+ <p>For Pre-Shared Key (PSK) cipher suites, the lookup fun is
+ called by the client and server to determine the shared
+ secret. When called by the client, <c>PSKIdentity</c> is set to the
+ hint presented by the server or to undefined. When called by the
+ server, <c>PSKIdentity</c> is the identity presented by the client.</p>
+
+ <p>For Secure Remote Password (SRP), the fun is only used by the server to
+ obtain parameters that it uses to generate its session keys.
+ <c>DerivedKey</c> is to be derived according to
+ <url href="http://tools.ietf.org/html/rfc2945#section-3"> RFC 2945</url> and
+ <url href="http://tools.ietf.org/html/rfc5054#section-2.4"> RFC 5054</url>:
+ <c>crypto:sha([Salt, crypto:sha([Username, &lt;&lt;$:&gt;&gt;, Password])])</c>
</p>
</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>
- </section>
+ <warning><p>Using <c>{padding_check, boolean()}</c> makes TLS
+ vulnerable to the Poodle attack.</p></warning>
- <section>
+ </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></tag>
+ <tag><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.
+ <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>{srp_identity, {Username :: string(), Password :: string()}</tag>
- <item>Specifies the Username and Password to use to authenticate to the server.
- </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><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 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>
+ <p><c> ssl:connect(Host, Port, [...{versions, ['tlsv1', 'sslv3']}, {fallback, true}]) </c></p>
+ <p><c> ssl:connect(Host, Port, [...{versions, ['sslv3']}, {fallback, true}]) </c></p>
+
+ <p>may use it to avoid undesired TLS version downgrade. Note that TLS_FALLBACK_SCSV must also
+ be supported by the server for the prevention to work.
+ </p></warning>
+ </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><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>{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>
+ <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>{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).
+ <p>The negotiated protocol can be retrieved using the <c>negotiated_protocol/1</c> function.</p>
</item>
- <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.
- </item>
+ <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 the <c>negotiated_next_protocol/1</c> method.</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><c>{psk_identity, string()}</c></tag>
+ <item><p>Specifies the server identity hint, which the server presents to
+ the client.</p></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
- 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.
- </item>
+ <tag><c>{log_alert, boolean()}</c></tag>
+ <item><p>If set to <c>false</c>, error reports are not displayed.</p></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>
- <item>If true, use the server's preference for cipher selection. If false
- (the default), use the client's preference.
- </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>
+
+
</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>
-
+
+ <func>
+ <name>clear_pem_cache() -> ok </name>
+ <fsummary> Clears the pem cache</fsummary>
+
+ <desc><p>PEM files, used by ssl API-functions, are cached. The
+ cache is regularly checked to see if any cache entries should be
+ invalidated, however this function provides a way to
+ unconditionally clear the whole cache.
+ </p>
+ </desc>
+ </func>
+
<func>
<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>
@@ -562,7 +699,7 @@ 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>
@@ -571,72 +708,70 @@ 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>connection_info(SslSocket) ->
+ {ok, {ProtocolVersion, CipherSuite}} | {error, Reason}</name>
+ <fsummary>Returns the Negotiated Protocol version and cipher suite.
+ </fsummary>
+ <type>
+ <v>CipherSuite = ciphersuite()</v>
+ <v>ProtocolVersion = protocol()</v>
+ </type>
+ <desc><p>Returns the Negotiated Protocol version and cipher suite.</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.
- </fsummary>
- <type>
- <v>CipherSuite = ciphersuite()</v>
- <v>ProtocolVersion = protocol()</v>
- </type>
- <desc><p>Returns the negotiated protocol version and cipher suite.</p>
- </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>
@@ -644,34 +779,49 @@ 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>
@@ -681,12 +831,32 @@ 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>
@@ -694,63 +864,43 @@ 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> &gt; 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>
@@ -758,31 +908,31 @@ 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>
@@ -790,16 +940,16 @@ 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>
@@ -807,7 +957,7 @@ 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>
@@ -815,17 +965,19 @@ 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>
@@ -833,14 +985,14 @@ 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>
@@ -848,22 +1000,21 @@ 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>
@@ -871,8 +1022,8 @@ 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>
@@ -881,66 +1032,66 @@ 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>
+ SSL application.</fsummary>
<type>
- <v>SslAppVer = string()</v>
- <v>SupportedSslVer = [protocol()]</v>
- <v>AvailableSslVsn = [protocol()]</v>
+ <v>versions_info() = {app_vsn, string()} | {supported | available, [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>
- <type>
- <v>Socket = sslsocket()</v>
- <v>Protocol = binary()</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_info-1">ssl:connection_info/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>
-