=item B<-named_curve>
-This sets the temporary curve used for ephemeral ECDH modes. Only used by
+This sets the temporary curve used for ephemeral ECDH modes. Only used by
servers
The B<value> argument is a curve name or the special value B<auto> which
=item B<-cipher>
Sets the cipher suite list to B<value>. Note: syntax checking of B<value> is
-currently not performed unless a B<SSL> or B<SSL_CTX> structure is
+currently not performed unless a B<SSL> or B<SSL_CTX> structure is
associated with B<cctx>.
=item B<-cert>
Attempts to use the file B<value> as the certificate for the appropriate
-context. It currently uses SSL_CTX_use_cerificate_chain_file if an B<SSL_CTX>
-structure is set or SSL_use_certifcate_file with filetype PEM if an B<SSL>
+context. It currently uses SSL_CTX_use_certificate_chain_file() if an B<SSL_CTX>
+structure is set or SSL_use_certificate_file() with filetype PEM if an B<SSL>
structure is set. This option is only supported if certificate operations
are permitted.
Attempts to use the file B<value> as the private key for the appropriate
context. This option is only supported if certificate operations
are permitted. Note: if no B<-key> option is set then a private key is
-not loaded: it does not currently use the B<-cert> file.
+not loaded unless the flag B<SSL_CONF_FLAG_REQUIRE_PRIVATE> is set.
=item B<-dhparam>
the appropriate context. This option is only supported if certificate
operations are permitted.
-=item B<-no_ssl2>, B<-no_ssl3>, B<-no_tls1>, B<-no_tls1_1>, B<-no_tls1_2>
+=item B<-min_protocol>, B<-max_protocol>
-Disables protocol support for SSLv2, SSLv3, TLS 1.0, TLS 1.1 or TLS 1.2
-by setting the corresponding options B<SSL_OP_NO_SSL2>, B<SSL_OP_NO_SSL3>,
-B<SSL_OP_NO_TLS1>, B<SSL_OP_NO_TLS1_1> and B<SSL_OP_NO_TLS1_2> respectively.
+Sets the minimum and maximum supported protocol.
+Currently supported protocol values are B<SSLv3>, B<TLSv1>,
+B<TLSv1.1>, B<TLSv1.2> for TLS and B<DTLSv1>, B<DTLSv1.2> for DTLS,
+and B<None> for no limit.
+If the either bound is not specified then only the other bound applies,
+if specified.
+To restrict the supported protocol versions use these commands rather
+than the deprecated alternative commands below.
+
+=item B<-no_ssl3>, B<-no_tls1>, B<-no_tls1_1>, B<-no_tls1_2>
+
+Disables protocol support for SSLv3, TLS 1.0, TLS 1.1 or TLS 1.2
+by setting the corresponding options B<SSL_OP_NO_SSL3>, B<SSL_OP_NO_TLS1>,
+B<SSL_OP_NO_TLS1_1> and B<SSL_OP_NO_TLS1_2> respectively.
+These options are deprecated, instead use B<-min_protocol> and B<-max_protocol>.
=item B<-bugs>
Various bug workarounds are set, same as setting B<SSL_OP_ALL>.
+=item B<-comp>
+
+Enables support for SSL/TLS compression, same as clearing
+B<SSL_OP_NO_COMPRESSION>.
+This command was introduced in OpenSSL 1.1.0.
+As of OpenSSL 1.1.0, compression is off by default.
+
=item B<-no_comp>
-Disables support for SSL/TLS compression, same as setting B<SSL_OP_NO_COMPRESS>.
+Disables support for SSL/TLS compression, same as setting
+B<SSL_OP_NO_COMPRESSION>.
+As of OpenSSL 1.1.0, compression is off by default.
=item B<-no_ticket>
enables strict mode protocol handling. Equivalent to setting
B<SSL_CERT_FLAG_TLS_STRICT>.
-=item B<-debug_broken_protocol>
-
-disables various checks and permits several kinds of broken protocol behaviour
-for testing purposes: it should B<NEVER> be used in anything other than a test
-environment. Only supported if OpenSSL is configured with
-B<-DOPENSSL_SSL_DEBUG_BROKEN_PROTOCOL>.
-
=back
=head1 SUPPORTED CONFIGURATION FILE COMMANDS
Currently supported B<cmd> names for configuration files (i.e. when the
flag B<SSL_CONF_FLAG_FILE> is set) are listed below. All configuration file
-B<cmd> names and are case insensitive so B<signaturealgorithms> is recognised
+B<cmd> names are case insensitive so B<signaturealgorithms> is recognised
as well as B<SignatureAlgorithms>. Unless otherwise stated the B<value> names
are also case insensitive.
=item B<CipherString>
Sets the cipher suite list to B<value>. Note: syntax checking of B<value> is
-currently not performed unless an B<SSL> or B<SSL_CTX> structure is
+currently not performed unless an B<SSL> or B<SSL_CTX> structure is
associated with B<cctx>.
=item B<Certificate>
Attempts to use the file B<value> as the certificate for the appropriate
-context. It currently uses SSL_CTX_use_cerificate_chain_file if an B<SSL_CTX>
-structure is set or SSL_use_certifcate_file with filetype PEM if an B<SSL>
+context. It currently uses SSL_CTX_use_certificate_chain_file() if an B<SSL_CTX>
+structure is set or SSL_use_certificate_file() with filetype PEM if an B<SSL>
structure is set. This option is only supported if certificate operations
are permitted.
Attempts to use the file B<value> as the private key for the appropriate
context. This option is only supported if certificate operations
-are permitted. Note: if no B<-key> option is set then a private key is
-not loaded: it does not currently use the B<Certificate> file.
+are permitted. Note: if no B<PrivateKey> option is set then a private key is
+not loaded unless the B<SSL_CONF_FLAG_REQUIRE_PRIVATE> is set.
+
+=item B<ChainCAFile>, B<ChainCAPath>, B<VerifyCAFile>, B<VerifyCAPath>
+
+These options indicate a file or directory used for building certificate
+chains or verifying certificate chains. These options are only supported
+if certificate operations are permitted.
=item B<ServerInfoFile>
=item B<ECDHParameters>
-This sets the temporary curve used for ephemeral ECDH modes. Only used by
+This sets the temporary curve used for ephemeral ECDH modes. Only used by
servers
The B<value> argument is a curve name or the special value B<Automatic> which
can be either the B<NIST> name (e.g. B<P-256>) or an OpenSSL OID name
(e.g B<prime256v1>). Curve names are case sensitive.
+=item B<MinProtocol>
+
+This sets the minimum supported SSL, TLS or DTLS version.
+
+Currently supported protocol values are B<SSLv3>, B<TLSv1>, B<TLSv1.1>,
+B<TLSv1.2>, B<DTLSv1> and B<DTLSv1.2>.
+The value B<None> will disable the limit.
+
+=item B<MaxProtocol>
+
+This sets the maximum supported SSL, TLS or DTLS version.
+
+Currently supported protocol values are B<SSLv3>, B<TLSv1>, B<TLSv1.1>,
+B<TLSv1.2>, B<DTLSv1> and B<DTLSv1.2>.
+The value B<None> will disable the limit.
+
=item B<Protocol>
-The supported versions of the SSL or TLS protocol.
+This can be used to enable or disable certain versions of the SSL,
+TLS or DTLS protocol.
+
+The B<value> argument is a comma separated list of supported protocols
+to enable or disable.
+If a protocol is preceded by B<-> that version is disabled.
-The B<value> argument is a comma separated list of supported protocols to
-enable or disable. If an protocol is preceded by B<-> that version is disabled.
-All versions are enabled by default, though applications may choose to
-explicitly disable some. Currently supported protocol values are B<SSLv2>,
-B<SSLv3>, B<TLSv1>, B<TLSv1.1> and B<TLSv1.2>. The special value B<ALL> refers
-to all supported versions.
+All protocol versions are enabled by default.
+You need to disable at least one protocol version for this setting have any
+effect.
+Only enabling some protocol versions does not disable the other protocol
+versions.
+
+Currently supported protocol values are B<SSLv3>, B<TLSv1>, B<TLSv1.1>,
+B<TLSv1.2>, B<DTLSv1> and B<DTLSv1.2>.
+The special value B<ALL> refers to all supported versions.
+
+This can't enable protocols that are disabled using B<MinProtocol>
+or B<MaxProtocol>, but can disable protocols that are still allowed
+by them.
+
+The B<Protocol> command is fragile and deprecated; do not use it.
+Use B<MinProtocol> and B<MaxProtocol> instead.
+If you do use B<Protocol>, make sure that the resulting range of enabled
+protocols has no "holes", e.g. if TLS 1.0 and TLS 1.2 are both enabled, make
+sure to also leave TLS 1.1 enabled.
=item B<Options>
The B<value> argument is a comma separated list of various flags to set.
-If a flag string is preceded B<-> it is disabled. See the
-B<SSL_CTX_set_options> function for more details of individual options.
+If a flag string is preceded B<-> it is disabled.
+See the L<SSL_CTX_set_options(3)> function for more details of
+individual options.
Each option is listed below. Where an operation is enabled by default
the B<-flag> syntax is needed to disable it.
for OpenSSL clients only. Equivalent to B<SSL_OP_LEGACY_SERVER_CONNECT>.
Set by default.
+=item B<VerifyMode>
+
+The B<value> argument is a comma separated list of flags to set.
+
+B<Peer> enables peer verification: for clients only.
+
+B<Request> requests but does not require a certificate from the client.
+Servers only.
+
+B<Require> requests and requires a certificate from the client: an error
+occurs if the client does not present a certificate. Servers only.
+
+B<Once> requests a certificate from a client only on the initial connection:
+not when renegotiating. Servers only.
+
+=item B<ClientCAFile>, B<ClientCAPath>
+
+A file or directory of certificates in PEM format whose names are used as the
+set of acceptable names for client CAs. Servers only. This option is only
+supported if certificate operations are permitted.
+
=back
=head1 SUPPORTED COMMAND TYPES
The value is a directory name.
+=item B<SSL_CONF_TYPE_NONE>
+
+The value string is not used e.g. a command line option which doesn't take an
+argument.
+
=back
=head1 NOTES
The order of operations is significant. This can be used to set either defaults
or values which cannot be overridden. For example if an application calls:
- SSL_CONF_cmd(ctx, "Protocol", "-SSLv2");
+ SSL_CONF_cmd(ctx, "Protocol", "-SSLv3");
SSL_CONF_cmd(ctx, userparam, uservalue);
-it will disable SSLv2 support by default but the user can override it. If
+it will disable SSLv3 support by default but the user can override it. If
however the call sequence is:
SSL_CONF_cmd(ctx, userparam, uservalue);
- SSL_CONF_cmd(ctx, "Protocol", "-SSLv2");
+ SSL_CONF_cmd(ctx, "Protocol", "-SSLv3");
-SSLv
2 is B<always> disabled and attempt to override this by the user are
+SSLv
3 is B<always> disabled and attempt to override this by the user are
ignored.
By checking the return code of SSL_CTX_cmd() it is possible to query if a
and an error is indicated. If 0 is returned some other error occurred and
this can be reported back to the user.
-The function SSL_CONF_cmd_value_type() can be used by applications to
+The function SSL_CONF_cmd_value_type() can be used by applications to
check for the existence of a command or to perform additional syntax
checking or translation of the command value. For example if the return
value is B<SSL_CONF_TYPE_FILE> an application could translate a relative
SSL_CONF_cmd(ctx, "SignatureAlgorithms", "ECDSA+SHA256:RSA+SHA256:DSA+SHA256");
-Enable all protocols except SSLv3 and SSLv2:
+There are various ways to select the supported procotols.
+
+This set the minimum protocol version to TLSv1, and so disables SSLv3.
+This is the recommended way to disable protocols.
+
+ SSL_CONF_cmd(ctx, "MinProtocol", "TLSv1");
- SSL_CONF_cmd(ctx, "Protocol", "ALL,-SSLv3,-SSLv2");
+The following also disables SSLv3:
+
+ SSL_CONF_cmd(ctx, "Protocol", "-SSLv3");
+
+The following will first enable all protocols, and then disable
+SSLv3.
+If no protocol versions were disabled before this has the same effect as
+"-SSLv3", but if some versions were disables this will re-enable them before
+disabling SSLv3.
+
+ SSL_CONF_cmd(ctx, "Protocol", "ALL,-SSLv3");
Only enable TLSv1.2:
+ SSL_CONF_cmd(ctx, "MinProtocol", "TLSv1.2");
+ SSL_CONF_cmd(ctx, "MaxProtocol", "TLSv1.2");
+
+This also only enables TLSv1.2:
+
SSL_CONF_cmd(ctx, "Protocol", "-ALL,TLSv1.2");
Disable TLS session tickets:
SSL_CONF_cmd(ctx, "Options", "-SessionTicket");
+Enable compression:
+
+ SSL_CONF_cmd(ctx, "Options", "Compression");
+
Set supported curves to P-256, P-384:
SSL_CONF_cmd(ctx, "Curves", "P-256:P-384");
=head1 SEE ALSO
-L<SSL_CONF_CTX_new(3)|SSL_CONF_CTX_new(3)>,
-L<SSL_CONF_CTX_set_flags(3)|SSL_CONF_CTX_set_flags(3)>,
-L<SSL_CONF_CTX_set1_prefix(3)|SSL_CONF_CTX_set1_prefix(3)>,
-L<SSL_CONF_CTX_set_ssl_ctx(3)|SSL_CONF_CTX_set_ssl_ctx(3)>,
-L<SSL_CONF_cmd_argv(3)|SSL_CONF_cmd_argv(3)>
+L<SSL_CONF_CTX_new(3)>,
+L<SSL_CONF_CTX_set_flags(3)>,
+L<SSL_CONF_CTX_set1_prefix(3)>,
+L<SSL_CONF_CTX_set_ssl_ctx(3)>,
+L<SSL_CONF_cmd_argv(3)>,
+L<SSL_CTX_set_options(3)>
=head1 HISTORY
SSL_CONF_cmd() was first added to OpenSSL 1.0.2
+B<SSL_OP_NO_SSL2> doesn't have effect since 1.1.0, but the macro is retained
+for backwards compatibility.
+
+B<SSL_CONF_TYPE_NONE> was first added to OpenSSL 1.1.0. In earlier versions of
+OpenSSL passing a command which didn't take an argument would return
+B<SSL_CONF_TYPE_UNKNOWN>.
+
+B<MinProtocol> and B<MaxProtocol> where added in OpenSSL 1.1.0.
+
=cut
projects / openssl.git / blobdiff