diff options
Diffstat (limited to 'lib/ssl/doc/src/ssl.xml')
| -rw-r--r-- | lib/ssl/doc/src/ssl.xml | 182 |
1 files changed, 101 insertions, 81 deletions
diff --git a/lib/ssl/doc/src/ssl.xml b/lib/ssl/doc/src/ssl.xml index f23b71e28b..e831f73530 100644 --- a/lib/ssl/doc/src/ssl.xml +++ b/lib/ssl/doc/src/ssl.xml @@ -31,37 +31,13 @@ <module>ssl</module> <modulesummary>Interface Functions for Secure Socket Layer</modulesummary> <description> - <p>This module contains interface functions for the SSL.</p> + <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> - - <list type="bulleted"> - <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 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 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 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>DATA TYPES</title> <p>The following data types are used in the functions for SSL:</p> @@ -84,11 +60,12 @@ <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> + <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()} {depth, integer()}</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' @@ -159,7 +136,7 @@ <tag><c>sslsocket() =</c></tag> <item><p>opaque()</p></item> - <tag><c>protocol() =</c></tag> + <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> @@ -167,7 +144,9 @@ <p>According to old API.</p></item> <tag><c>ciphersuite() =</c></tag> - <item><p><c>{key_exchange(), cipher(), hash()}</c></p></item> + + <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 @@ -179,7 +158,7 @@ | aes_128_cbc | aes_256_cbc | aes_128_gcm | aes_256_gcm</c></p></item> <tag><c>hash() =</c></tag> - <item><p><c>md5 | sha</c></p></item> + <item><p><c>md5 | sha | sha224 | sha256 | sha348 | sha512</c></p></item> <tag><c>prf_random() =</c></tag> <item><p><c>client_random | server_random</c></p></item> @@ -244,7 +223,7 @@ <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 + 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> @@ -292,7 +271,11 @@ atom()}} | 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> + 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> @@ -314,6 +297,8 @@ atom()}} | <code> {fun(_,{bad_cert, _}, UserState) -> {valid, UserState}; + (_,{extension, #'Extension'{critical = true}}, UserState) -> + {valid, UserState}; (_,{extension, _}, UserState) -> {unknown, UserState}; (_, valid, UserState) -> @@ -330,7 +315,7 @@ atom()}} | <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 + 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> @@ -375,7 +360,7 @@ marker="public_key:public_key#pkix_path_validation-3">public_key:pkix_path_valid <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 cerificate extensions.</seealso> + marker="public_key:public_key_records"> X509 certificate extensions.</seealso> Requires the OTP inets application.</p> </item> </taglist> @@ -436,7 +421,6 @@ fun(srp, Username :: string(), UserState :: term()) -> <warning><p>Using <c>{padding_check, boolean()}</c> makes TLS vulnerable to the Poodle attack.</p></warning> - </section> <section> @@ -479,8 +463,8 @@ fun(srp, Username :: string(), UserState :: term()) -> <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> + <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 that the client is to try to perform Next Protocol Negotiation.</p> @@ -537,10 +521,45 @@ 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> @@ -635,14 +654,14 @@ fun(srp, Username :: string(), UserState :: term()) -> <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 speicific options for + 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 retrive <c>ssloptions()</c> for indicated server. + 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: @@ -656,22 +675,25 @@ fun(srp, Username :: string(), UserState :: term()) -> 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 stricly disabled by setting + 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><c>{psk_identity, string()}</c></tag> - <item>Specifies the server identity hint the server presents to the client. - </item> - <tag><c>{log_alert, boolean()}</c></tag> - <item>If false, error reports will not be displayed.</item> <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> @@ -770,18 +792,20 @@ fun(srp, Username :: string(), UserState :: term()) -> </func> <func> - <name>connection_info(SslSocket) -> - {ok, {ProtocolVersion, CipherSuite}} | {error, Reason}</name> - <fsummary>Returns the Negotiated Protocol version and cipher suite. - </fsummary> + <name>close(SslSocket, How) -> ok | {ok, port()} | {error, Reason}</name> + <fsummary>Closes an SSL connection.</fsummary> <type> - <v>CipherSuite = ciphersuite()</v> - <v>ProtocolVersion = protocol()</v> + <v>SslSocket = sslsocket()</v> + <v>How = timeout() | {NewController::pid(), timeout()} </v> + <v>Reason = term()</v> </type> - <desc><p>Returns the Negotiated Protocol version and cipher suite.</p> + <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> @@ -800,40 +824,36 @@ fun(srp, Username :: string(), UserState :: term()) -> <func> <name>connection_information(SslSocket) -> - {ok, Info} | {error, Reason} </name> + {ok, Result} | {error, Reason} </name> <fsummary>Returns all the connection information. </fsummary> <type> - <v>Info = [InfoTuple]</v> - <v>InfoTuple = {protocol, Protocol} | {cipher_suite, CipherSuite} | {sni_hostname, SNIHostname}</v> - <v>CipherSuite = ciphersuite()</v> - <v>ProtocolVersion = protocol()</v> - <v>SNIHostname = string()</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>Return all the connection information containing negotiated protocol version, cipher suite, and the hostname of SNI extension. - Info will be a proplists containing all the connection information on success, otherwise <c>{error, Reason}</c> will be returned.</p> + <desc><p>Returns all relevant information about the connection, ssl options that + are undefined will be filtered out.</p> </desc> </func> <func> <name>connection_information(SslSocket, Items) -> - {ok, Info} | {error, Reason} </name> + {ok, Result} | {error, Reason} </name> <fsummary>Returns the requested connection information. </fsummary> <type> - <v>Items = [Item]</v> - <v>Item = protocol | cipher_suite | sni_hostname</v> - <v>Info = [InfoTuple]</v> - <v>InfoTuple = {protocol, Protocol} | {cipher_suite, CipherSuite} | {sni_hostname, SNIHostname}</v> - <v>CipherSuite = ciphersuite()</v> - <v>ProtocolVersion = protocol()</v> - <v>SNIHostname = string()</v> + <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 connection information you requested. The connection information you can request contains protocol, cipher_suite, and sni_hostname. - <c>{ok, Info}</c> will be returned if it executes sucessfully. The Info is a proplists containing the information you requested. - Otherwise, <c>{error, Reason}</c> will be returned.</p> + <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> @@ -1160,7 +1180,7 @@ fun(srp, Username :: string(), UserState :: term()) -> <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 + marker="#connection_information-1">ssl:connection_information/1 </seealso>.</item> <tag><c>available</c></tag> |