=head1 NAME
-SSL_CONF_cmd_value_type, SSL_CONF_finish,
+SSL_CONF_cmd_value_type,
SSL_CONF_cmd - send configuration command
=head1 SYNOPSIS
int SSL_CONF_cmd(SSL_CONF_CTX *cctx, const char *cmd, const char *value);
int SSL_CONF_cmd_value_type(SSL_CONF_CTX *cctx, const char *cmd);
- int SSL_CONF_finish(SSL_CONF_CTX *cctx);
=head1 DESCRIPTION
SSL_CONF_cmd_value_type() returns the type of value that B<cmd> refers to.
-The function SSL_CONF_finish() must be called after all configuration
-operations have been completed. It is used to finalise any operations
-or to process defaults.
-
=head1 SUPPORTED COMMAND LINE COMMANDS
Currently supported B<cmd> names for command lines (i.e. when the
=item B<-sigalgs>
-This sets the supported signature algorithms for TLS v1.2. For clients this
+This sets the supported signature algorithms for TLSv1.2 and TLSv1.3.
+For clients this
value is used directly for the supported signature algorithms extension. For
servers it is used to determine which signature algorithms to support.
The B<value> argument should be a colon separated list of signature algorithms
-in order of decreasing preference of the form B<algorithm+hash>. B<algorithm>
+in order of decreasing preference of the form B<algorithm+hash> or
+B<signature_scheme>. B<algorithm>
is one of B<RSA>, B<DSA> or B<ECDSA> and B<hash> is a supported algorithm
OID short name such as B<SHA1>, B<SHA224>, B<SHA256>, B<SHA384> of B<SHA512>.
Note: algorithm and hash names are case sensitive.
+B<signature_scheme> is one of the signature schemes defined in TLSv1.3,
+specified using the IETF name, e.g., B<ecdsa_secp256r1_sha256>, B<ed25519>,
+or B<rsa_pss_pss_sha256>.
If this option is not set then all signature algorithms supported by the
OpenSSL library are permissible.
+Note: algorithms which specify a PKCS#1 v1.5 signature scheme (either by
+using B<RSA> as the B<algorithm> or by using one of the B<rsa_pkcs1_*>
+identifiers) are ignored in TLSv1.3 and will not be negotiated.
+
=item B<-client_sigalgs>
This sets the supported signature algorithms associated with client
-authentication for TLS v1.2. For servers the value is used in the supported
-signature algorithms field of a certificate request. For clients it is
-used to determine which signature algorithm to with the client certificate.
+authentication for TLSv1.2 and TLSv1.3.
+For servers the value is used in the
+B<signature_algorithms> field of a B<CertificateRequest> message.
+For clients it is
+used to determine which signature algorithm to use with the client certificate.
If a server does not request a certificate this option has no effect.
The syntax of B<value> is identical to B<-sigalgs>. If not set then
the value set for B<-sigalgs> will be used instead.
-=item B<-curves>
+=item B<-groups>
+
+This sets the supported groups. For clients, the groups are
+sent using the supported groups extension. For servers, it is used
+to determine which group to use. This setting affects groups used for
+signatures (in TLSv1.2 and earlier) and key exchange. The first group listed
+will also be used for the B<key_share> sent by a client in a TLSv1.3
+B<ClientHello>.
+
+The B<value> argument is a colon separated list of groups. The group can be
+either the B<NIST> name (e.g. B<P-256>), some other commonly used name where
+applicable (e.g. B<X25519>) or an OpenSSL OID name (e.g B<prime256v1>). Group
+names are case sensitive. The list should be in order of preference with the
+most preferred group first.
-This sets the supported elliptic curves. For clients the curves are
-sent using the supported curves extension. For servers it is used
-to determine which curve to use. This setting affects curves used for both
-signatures and key exchange, if applicable.
+=item B<-curves>
-The B<value> argument is a colon separated list of curves. The curve 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.
+This is a synonym for the "-groups" command.
=item B<-named_curve>
=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
+Sets the TLSv1.2 and below ciphersuite list to B<value>. This list will be
+combined with any configured TLSv1.3 ciphersuites. Note: syntax checking
+of B<value> is currently not performed unless a B<SSL> or B<SSL_CTX> structure is
associated with B<cctx>.
+=item B<-ciphersuites>
+
+Sets the available ciphersuites for TLSv1.3 to value. This is a simple colon
+(":") separated list of TLSv1.3 ciphersuite names in order of preference. This
+list will be combined any configured TLSv1.2 and below ciphersuites.
+See L<ciphers(1)> for more information.
+
+
=item B<-cert>
Attempts to use the file B<value> as the certificate for the appropriate
the appropriate context. This option is only supported if certificate
operations are permitted.
+=item B<-record_padding>
+
+Attempts to pad TLSv1.3 records so that they are a multiple of B<value> in
+length on send. A B<value> of 0 or 1 turns off padding. Otherwise, the
+B<value> must be >1 or <=16384.
+
+=item B<-no_renegotiation>
+
+Disables all attempts at renegotiation in TLSv1.2 and earlier, same as setting
+B<SSL_OP_NO_RENEGOTIATION>.
+
=item B<-min_protocol>, B<-max_protocol>
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,
+B<TLSv1.1>, B<TLSv1.2>, B<TLSv1.3> 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 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.
signature algorithm or elliptic curve to use for an incoming connection.
Equivalent to B<SSL_OP_CIPHER_SERVER_PREFERENCE>. Only used by servers.
+=item B<-prioritize_chacha>
+
+Prioritize ChaCha ciphers when the client has a ChaCha20 cipher at the top of
+its preference list. This usually indicates a client without AES hardware
+acceleration (e.g. mobile) is in use. Equivalent to B<SSL_OP_PRIORITIZE_CHACHA>.
+Only used by servers. Requires B<-serverpref>.
+
=item B<-no_resumption_on_reneg>
set SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION flag. Only used by servers.
clients only. Equivalent to setting or clearing B<SSL_OP_LEGACY_SERVER_CONNECT>.
Set by default.
+=item B<-allow_no_dhe_kex>
+
+In TLSv1.3 allow a non-(ec)dhe based key exchange mode on resumption. This means
+that there will be no forward secrecy for the resumed session.
+
=item B<-strict>
enables strict mode protocol handling. Equivalent to setting
B<SSL_CERT_FLAG_TLS_STRICT>.
+=item B<-anti_replay>, B<-no_anti_replay>
+
+Switches replay protection, on or off respectively. With replay protection on,
+OpenSSL will automatically detect if a session ticket has been used more than
+once, TLSv1.3 has been negotiated, and early data is enabled on the server. A
+full handshake is forced if a session ticket is used a second or subsequent
+time. Anti-Replay is on by default unless overridden by a configuration file and
+is only used by servers. Anti-replay measures are required for compliance with
+the TLSv1.3 specification. Some applications may be able to mitigate the replay
+risks in other ways and in such cases the built-in OpenSSL functionality is not
+required. Switching off anti-replay is equivalent to B<SSL_OP_NO_ANTI_REPLAY>.
+
=back
=head1 SUPPORTED CONFIGURATION FILE COMMANDS
=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
-associated with B<cctx>.
+Sets the ciphersuite list for TLSv1.2 and below to B<value>. This list will be
+combined with any configured TLSv1.3 ciphersuites. Note: syntax
+checking of B<value> is currently not performed unless an B<SSL> or B<SSL_CTX>
+structure is associated with B<cctx>.
+
+=item B<Ciphersuites>
+
+Sets the available ciphersuites for TLSv1.3 to B<value>. This is a simple colon
+(":") separated list of TLSv1.3 ciphersuite names in order of preference. This
+list will be combined any configured TLSv1.2 and below ciphersuites.
+See L<ciphers(1)> for more information.
=item B<Certificate>
chains or verifying certificate chains. These options are only supported
if certificate operations are permitted.
+=item B<RequestCAFile>
+
+This option indicates a file containing a set of certificates in PEM form.
+The subject names of the certificates are sent to the peer in the
+B<certificate_authorities> extension for TLS 1.3 (in ClientHello or
+CertificateRequest) or in a certificate request for previous versions or
+TLS.
+
=item B<ServerInfoFile>
Attempts to use the file B<value> in the "serverinfo" extension using the
the appropriate context. This option is only supported if certificate
operations are permitted.
+=item B<RecordPadding>
+
+Attempts to pad TLSv1.3 records so that they are a multiple of B<value> in
+length on send. A B<value> of 0 or 1 turns off padding. Otherwise, the
+B<value> must be >1 or <=16384.
+
=item B<SignatureAlgorithms>
-This sets the supported signature algorithms for TLS v1.2. For clients this
+This sets the supported signature algorithms for TLSv1.2 and TLSv1.3.
+For clients this
value is used directly for the supported signature algorithms extension. For
servers it is used to determine which signature algorithms to support.
The B<value> argument should be a colon separated list of signature algorithms
-in order of decreasing preference of the form B<algorithm+hash>. B<algorithm>
+in order of decreasing preference of the form B<algorithm+hash> or
+B<signature_scheme>. B<algorithm>
is one of B<RSA>, B<DSA> or B<ECDSA> and B<hash> is a supported algorithm
OID short name such as B<SHA1>, B<SHA224>, B<SHA256>, B<SHA384> of B<SHA512>.
Note: algorithm and hash names are case sensitive.
+B<signature_scheme> is one of the signature schemes defined in TLSv1.3,
+specified using the IETF name, e.g., B<ecdsa_secp256r1_sha256>, B<ed25519>,
+or B<rsa_pss_pss_sha256>.
If this option is not set then all signature algorithms supported by the
OpenSSL library are permissible.
+Note: algorithms which specify a PKCS#1 v1.5 signature scheme (either by
+using B<RSA> as the B<algorithm> or by using one of the B<rsa_pkcs1_*>
+identifiers) are ignored in TLSv1.3 and will not be negotiated.
+
=item B<ClientSignatureAlgorithms>
This sets the supported signature algorithms associated with client
-authentication for TLS v1.2. For servers the value is used in the supported
-signature algorithms field of a certificate request. For clients it is
-used to determine which signature algorithm to with the client certificate.
+authentication for TLSv1.2 and TLSv1.3.
+For servers the value is used in the
+B<signature_algorithms> field of a B<CertificateRequest> message.
+For clients it is
+used to determine which signature algorithm to use with the client certificate.
+If a server does not request a certificate this option has no effect.
The syntax of B<value> is identical to B<SignatureAlgorithms>. If not set then
the value set for B<SignatureAlgorithms> will be used instead.
-=item B<Curves>
+=item B<Groups>
-This sets the supported elliptic curves. For clients the curves are
-sent using the supported curves extension. For servers it is used
-to determine which curve to use. This setting affects curves used for both
-signatures and key exchange, if applicable.
+This sets the supported groups. For clients, the groups are
+sent using the supported groups extension. For servers, it is used
+to determine which group to use. This setting affects groups used for
+signatures (in TLSv1.2 and earlier) and key exchange. The first group listed
+will also be used for the B<key_share> sent by a client in a TLSv1.3
+B<ClientHello>.
-The B<value> argument is a colon separated list of curves. The curve 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.
+The B<value> argument is a colon separated list of groups. The group can be
+either the B<NIST> name (e.g. B<P-256>), some other commonly used name where
+applicable (e.g. B<X25519>) or an OpenSSL OID name (e.g B<prime256v1>). Group
+names are case sensitive. The list should be in order of preference with the
+most preferred group first.
+
+=item B<Curves>
+
+This is a synonym for the "Groups" command.
=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>.
+B<TLSv1.2>, B<TLSv1.3>, 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>.
+B<TLSv1.2>, B<TLSv1.3>, B<DTLSv1> and B<DTLSv1.2>.
The value B<None> will disable the limit.
=item B<Protocol>
versions.
Currently supported protocol values are B<SSLv3>, B<TLSv1>, B<TLSv1.1>,
-B<TLSv1.2>, B<DTLSv1> and B<DTLSv1.2>.
+B<TLSv1.2>, B<TLSv1.3>, 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>
B<DHSingle>: enable single use DH keys, set by default. Inverse of
B<SSL_OP_DH_SINGLE>. Only used by servers.
-B<ECDHSingle> enable single use ECDH keys, set by default. Inverse of
+B<ECDHSingle>: enable single use ECDH keys, set by default. Inverse of
B<SSL_OP_ECDH_SINGLE>. Only used by servers.
-B<ServerPreference> use server and not client preference order when
+B<ServerPreference>: use server and not client preference order when
determining which cipher suite, signature algorithm or elliptic curve
to use for an incoming connection. Equivalent to
B<SSL_OP_CIPHER_SERVER_PREFERENCE>. Only used by servers.
-B<NoResumptionOnRenegotiation> set
+B<PrioritizeChaCha>: prioritizes ChaCha ciphers when the client has a
+ChaCha20 cipher at the top of its preference list. This usually indicates
+a mobile client is in use. Equivalent to B<SSL_OP_PRIORITIZE_CHACHA>.
+Only used by servers.
+
+B<NoResumptionOnRenegotiation>: set
B<SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION> flag. Only used by servers.
-B<UnsafeLegacyRenegotiation> permits the use of unsafe legacy renegotiation.
+B<NoRenegotiation>: disables all attempts at renegotiation in TLSv1.2 and
+earlier, same as setting B<SSL_OP_NO_RENEGOTIATION>.
+
+B<UnsafeLegacyRenegotiation>: permits the use of unsafe legacy renegotiation.
Equivalent to B<SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION>.
-B<UnsafeLegacyServerConnect> permits the use of unsafe legacy renegotiation
+B<UnsafeLegacyServerConnect>: permits the use of unsafe legacy renegotiation
for OpenSSL clients only. Equivalent to B<SSL_OP_LEGACY_SERVER_CONNECT>.
Set by default.
+B<EncryptThenMac>: use encrypt-then-mac extension, enabled by
+default. Inverse of B<SSL_OP_NO_ENCRYPT_THEN_MAC>: that is,
+B<-EncryptThenMac> is the same as setting B<SSL_OP_NO_ENCRYPT_THEN_MAC>.
+
+B<AllowNoDHEKEX>: In TLSv1.3 allow a non-(ec)dhe based key exchange mode on
+resumption. This means that there will be no forward secrecy for the resumed
+session. Equivalent to B<SSL_OP_ALLOW_NO_DHE_KEX>.
+
+B<MiddleboxCompat>: If set then dummy Change Cipher Spec (CCS) messages are sent
+in TLSv1.3. This has the effect of making TLSv1.3 look more like TLSv1.2 so that
+middleboxes that do not understand TLSv1.3 will not drop the connection. This
+option is set by default. A future version of OpenSSL may not set this by
+default. Equivalent to B<SSL_OP_ENABLE_MIDDLEBOX_COMPAT>.
+
+B<AntiReplay>: If set then OpenSSL will automatically detect if a session ticket
+has been used more than once, TLSv1.3 has been negotiated, and early data is
+enabled on the server. A full handshake is forced if a session ticket is used a
+second or subsequent time. This option is set by default and is only used by
+servers. Anti-replay measures are required to comply with the TLSv1.3
+specification. Some applications may be able to mitigate the replay risks in
+other ways and in such cases the built-in OpenSSL functionality is not required.
+Disabling anti-replay is equivalent to setting B<SSL_OP_NO_ANTI_REPLAY>.
+
+B<ExtendedMasterSecret>: use extended master secret extension, enabled by
+default. Inverse of B<SSL_OP_NO_EXTENDED_MASTER_SECRET>: that is,
+B<-ExtendedMasterSecret> is the same as setting B<SSL_OP_NO_EXTENDED_MASTER_SECRET>.
+
=item B<VerifyMode>
The B<value> argument is a comma separated list of flags to set.
B<Once> requests a certificate from a client only on the initial connection:
not when renegotiating. Servers only.
+B<RequestPostHandshake> configures the connection to support requests but does
+not require a certificate from the client post-handshake. A certificate will
+not be requested during the initial handshake. The server application must
+provide a mechanism to request a certificate post-handshake. Servers only.
+TLSv1.3 only.
+
+B<RequiresPostHandshake> configures the connection to support requests and
+requires a certificate from the client post-handshake: an error occurs if the
+client does not present a certificate. A certificate will not be requested
+during the initial handshake. The server application must provide a mechanism
+to request a certificate post-handshake. Servers only. TLSv1.3 only.
+
=item B<ClientCAFile>, B<ClientCAPath>
A file or directory of certificates in PEM format whose names are used as the
SSLv3 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
-given B<cmd> is recognised, this is useful is SSL_CTX_cmd() values are
+By checking the return code of SSL_CONF_cmd() it is possible to query if a
+given B<cmd> is recognised, this is useful if SSL_CONF_cmd() values are
mixed with additional application specific operations.
-For example an application might call SSL_CTX_cmd() and if it returns
+For example an application might call SSL_CONF_cmd() and if it returns
-2 (unrecognised command) continue with processing of application specific
commands.
-Applications can also use SSL_CTX_cmd() to process command lines though the
-utility function SSL_CTX_cmd_argv() is normally used instead. One way
+Applications can also use SSL_CONF_cmd() to process command lines though the
+utility function SSL_CONF_cmd_argv() is normally used instead. One way
to do this is to set the prefix to an appropriate value using
SSL_CONF_CTX_set1_prefix(), pass the current argument to B<cmd> and the
following argument to B<value> (which may be NULL).
In this case if the return value is positive then it is used to skip that
-number of arguments as they have been processed by SSL_CTX_cmd(). If -2 is
+number of arguments as they have been processed by SSL_CONF_cmd(). If -2 is
returned then B<cmd> is not recognised and application specific arguments
can be checked instead. If -3 is returned a required argument is missing
and an error is indicated. If 0 is returned some other error occurred and
value is B<SSL_CONF_TYPE_FILE> an application could translate a relative
pathname to an absolute pathname.
+=head1 RETURN VALUES
+
+SSL_CONF_cmd() returns 1 if the value of B<cmd> is recognised and B<value> is
+B<NOT> used and 2 if both B<cmd> and B<value> are used. In other words it
+returns the number of arguments processed. This is useful when processing
+command lines.
+
+A return value of -2 means B<cmd> is not recognised.
+
+A return value of -3 means B<cmd> is recognised and the command requires a
+value but B<value> is NULL.
+
+A return code of 0 indicates that both B<cmd> and B<value> are valid but an
+error occurred attempting to perform the operation: for example due to an
+error in the syntax of B<value> in this case the error queue may provide
+additional information.
+
=head1 EXAMPLES
Set supported signature algorithms:
SSL_CONF_cmd(ctx, "Curves", "P-256:P-384");
-Set automatic support for any elliptic curve for key exchange:
-
- SSL_CONF_cmd(ctx, "ECDHParameters", "Automatic");
-
-=head1 RETURN VALUES
-
-SSL_CONF_cmd() returns 1 if the value of B<cmd> is recognised and B<value> is
-B<NOT> used and 2 if both B<cmd> and B<value> are used. In other words it
-returns the number of arguments processed. This is useful when processing
-command lines.
-
-A return value of -2 means B<cmd> is not recognised.
-
-A return value of -3 means B<cmd> is recognised and the command requires a
-value but B<value> is NULL.
-
-A return code of 0 indicates that both B<cmd> and B<value> are valid but an
-error occurred attempting to perform the operation: for example due to an
-error in the syntax of B<value> in this case the error queue may provide
-additional information.
-
-SSL_CONF_finish() returns 1 for success and 0 for failure.
-
=head1 SEE ALSO
L<SSL_CONF_CTX_new(3)>,
=head1 HISTORY
-SSL_CONF_cmd() was first added to OpenSSL 1.0.2
+The SSL_CONF_cmd() function was added in 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.
+The B<SSL_OP_NO_SSL2> option 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
+The B<SSL_CONF_TYPE_NONE> was added in 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.
+B<AllowNoDHEKEX> and B<PrioritizeChaCha> were added in OpenSSL 1.1.1.
+
=head1 COPYRIGHT
-Copyright 2012-2016 The OpenSSL Project Authors. All Rights Reserved.
+Copyright 2012-2018 The OpenSSL Project Authors. All Rights Reserved.
-Licensed under the OpenSSL license (the "License"). You may not use
+Licensed under the Apache License 2.0 (the "License"). You may not use
this file except in compliance with the License. You can obtain a copy
in the file LICENSE in the source distribution or at
L<https://www.openssl.org/source/license.html>.
projects / openssl.git / blobdiff