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-rw-r--r--lib/ssl/doc/src/ssl.xml174
1 files changed, 150 insertions, 24 deletions
diff --git a/lib/ssl/doc/src/ssl.xml b/lib/ssl/doc/src/ssl.xml
index b53344e381..47b0dbc206 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>
@@ -38,7 +38,9 @@
<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>For security reasons SSL-2.0 is not supported.</item>
+ <item>For security reasons SSL-3.0 is no longer supported by default,
+ but may 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
@@ -49,9 +51,9 @@
<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>CRL validation is supported.</item>
+ <item>Policy certificate extensions are not supported
+ yet. </item>
<item>Support for 'Server Name Indication' extension client side
(RFC 6066 section 3).</item>
</list>
@@ -87,12 +89,14 @@
|{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()}
+ {alpn_advertised_protocols, [binary()]} |
+ {alpn_preferred_protocols, [binary()]} |
{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()}}
+ <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
@@ -136,7 +140,7 @@
</c></p>
<p><c>cipher() = rc4_128 | des_cbc | '3des_ede_cbc'
- | aes_128_cbc | aes_256_cbc </c></p>
+ | aes_128_cbc | aes_256_cbc | aes_128_gcm | aes_256_gcm </c></p>
<p> <c>hash() = md5 | sha
</c></p>
@@ -163,7 +167,7 @@
is supplied it will override the certfile option.</item>
<tag>{certfile, path()}</tag>
- <item>Path to a file containing the user's certificate.</item>
+ <item>Path to a file containing the user's PEM encoded certificate.</item>
<tag>{key, {'RSAPrivateKey'| 'DSAPrivateKey' | 'ECPrivateKey' |'PrivateKeyInfo', der_encoded()}}</tag>
<item> The DER encoded users private key. If this option
@@ -299,10 +303,47 @@ fun(OtpCert :: #'OTPCertificate'{}, Event :: {bad_cert, Reason :: atom() | {revo
<item> Possible such reasons see <seealso
marker="public_key:public_key#pkix_path_validation-3"> public_key:pkix_path_validation/3 </seealso></item>
</taglist>
+ </item>
+
+ <tag>{crl_check, boolean() | peer | best_effort }</tag>
+ <item>
+ Perform CRL (Certificate Revocation List) verification
+ <seealso marker="public_key:public_key#pkix_crl_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>
+
+ <p><c>best_effort</c> - if certificate revocation status can not be determined
+ it will be accepted as valid.</p>
+ <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
+ <seealso marker="ssl:ssl_crl_cache_api">ssl_crl_cache_api(3)</seealso>.</p>
</item>
+ <tag>{crl_cache, {Module :: atom(), {DbHandle :: internal | term(), Args :: list()}}}</tag>
+ <item>
+ <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>{http, timeout()}</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>{partial_chain, fun(Chain::[DerCert]) -> {trusted_ca, DerCert} | unknown_ca </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.
@@ -311,7 +352,7 @@ fun(OtpCert :: #'OTPCertificate'{}, Event :: {bad_cert, Reason :: atom() | {revo
<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
+ 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>
</item>
@@ -348,11 +389,23 @@ fun(srp, Username :: string(), UserState :: term()) ->
</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>
+
</taglist>
-
+
</section>
-
- <section>
+
+ <section>
<title>SSL OPTION DESCRIPTIONS - CLIENT SIDE</title>
<p>Options described here are client specific or has a slightly different
@@ -374,7 +427,20 @@ fun(srp, Username :: string(), UserState :: term()) ->
certificates are used during server authentication and when building the
client certificate chain.
</item>
-
+
+ <tag>{alpn_advertised_protocols, [binary()]}</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>{client_preferred_next_protocols, {Precedence :: server | client, ClientPrefs :: [binary()]}}</tag>
<tag>{client_preferred_next_protocols, {Precedence :: server | client, ClientPrefs :: [binary()], Default :: binary()}}</tag>
<item>
@@ -413,6 +479,23 @@ fun(srp, Username :: string(), UserState :: term()) ->
Indication extension will be sent if possible, this option may also be
used to disable that behavior.</p>
</item>
+ <tag>{fallback, boolean()}</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>
+
+ <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>
@@ -477,12 +560,25 @@ fun(srp, Username :: string(), UserState :: term()) ->
and CipherSuite is of type ciphersuite().
</item>
+ <tag>{alpn_preferred_protocols, [binary()]}</tag>
+ <item>
+ <p>Indicates the server will try to perform Application-Layer
+ Protocol Negotiation (ALPN).</p>
+
+ <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>
+
+ <p>The negotiated protocol can be retrieved using the <c>negotiated_protocol/1</c> function.</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.
+ using <c>negotiated_protocol/1</c> function.
</item>
<tag>{psk_identity, string()}</tag>
@@ -538,7 +634,19 @@ fun(srp, Username :: string(), UserState :: term()) ->
</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}
@@ -904,31 +1012,49 @@ fun(srp, Username :: string(), UserState :: term()) ->
</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>
+ <v>versions_info() = {app_vsn, string()} | {supported | available, [protocol()] </v>
</type>
<desc>
<p>
Returns version information relevant for the
- ssl application.</p>
+ ssl application.
+ </p>
+ <taglist>
+ <tag>app_vsn</tag>
+ <item> The application version of the OTP ssl application.</item>
+
+ <tag>supported</tag>
+
+ <item>TLS/SSL versions supported by default.
+ Overridden by a versions 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>available</tag>
+ <item>All TLS/SSL versions that the Erlang ssl application
+ can support. Note that TLS 1.2 requires sufficient support
+ from the crypto application. </item>
+ </taglist>
</desc>
</func>
<func>
- <name>negotiated_next_protocol(Socket) -> {ok, Protocol} | {error, next_protocol_not_negotiated}</name>
- <fsummary>Returns the Next Protocol negotiated.</fsummary>
+ <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 Next Protocol negotiated.
+ Returns the protocol negotiated through ALPN or NPN extensions.
</p>
</desc>
</func>