=head1 NAME
-SSL_CTX_set_options, SSL_set_options, SSL_CTX_clear_options, SSL_clear_options, SSL_CTX_get_options, SSL_get_options, SSL_get_secure_renegotiation_support - manipulate SSL options
+SSL_CTX_set_options, SSL_set_options, SSL_CTX_clear_options,
+SSL_clear_options, SSL_CTX_get_options, SSL_get_options,
+SSL_get_secure_renegotiation_support - manipulate SSL options
=head1 SYNOPSIS
=head1 DESCRIPTION
-Note: all these functions are implemented using macros.
-
SSL_CTX_set_options() adds the options set via bitmask in B<options> to B<ctx>.
Options already set before are not cleared!
SSL_get_secure_renegotiation_support() indicates whether the peer supports
secure renegotiation.
+Note, this is implemented via a macro.
=head1 NOTES
=over 4
-=item SSL_OP_MICROSOFT_SESS_ID_BUG
-
-As of OpenSSL 1.0.0 this option has no effect.
-
-=item SSL_OP_NETSCAPE_CHALLENGE_BUG
-
-As of OpenSSL 1.0.0 this option has no effect.
-
-=item SSL_OP_NETSCAPE_REUSE_CIPHER_CHANGE_BUG
-
-As of OpenSSL 0.9.8q and 1.0.0c, this option has no effect.
-
=item SSL_OP_SSLREF2_REUSE_CERT_TYPE_BUG
...
When choosing a cipher, use the server's preferences instead of the client
preferences. When not set, the SSL server will always follow the clients
-preferences. When set, the SSLv3/TLSv1 server will choose following its
-own preferences. Because of the different protocol, for SSLv2 the server
-will send its list of preferences to the client and the client chooses.
+preferences. When set, the SSL/TLS server will choose following its
+own preferences.
=item SSL_OP_PKCS1_CHECK_1
...
+=item SSL_OP_NO_SSLv3, SSL_OP_NO_TLSv1, SSL_OP_NO_TLSv1_1,
+SSL_OP_NO_TLSv1_2, SSL_OP_NO_DTLSv1, SSL_OP_NO_DTLSv1_2
-=item SSL_OP_NO_SSLv2
-
-Do not use the SSLv2 protocol.
-
-=item SSL_OP_NO_SSLv3
-
-Do not use the SSLv3 protocol.
-
-=item SSL_OP_NO_TLSv1
-
-Do not use the TLSv1 protocol.
+These options turn off the SSLv3, TLSv1, TLSv1.1 or TLSv1.2 protocol
+versions with TLS or the DTLSv1, DTLSv1.2 versions with DTLS,
+respectively.
+As of OpenSSL 1.1.0, these options are deprecated, use
+L<SSL_CTX_set_min_proto_version(3)> and
+L<SSL_CTX_set_max_proto_version(3)> instead.
=item SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION
=head1 SECURE RENEGOTIATION
-OpenSSL 0.9.8m and later always attempts to use secure renegotiation as
+OpenSSL always attempts to use secure renegotiation as
described in RFC5746. This counters the prefix attack described in
CVE-2009-3555 and elsewhere.
-The deprecated and highly broken SSLv2 protocol does not support
-renegotiation at all: its use is B<strongly> discouraged.
-
This attack has far reaching consequences which application writers should be
aware of. In the description below an implementation supporting secure
renegotiation is referred to as I<patched>. A server not supporting secure
If the option B<SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION> is set then
renegotiation B<always> succeeds.
-B<NB:> a bug in OpenSSL clients earlier than 0.9.8m (all of which are
-unpatched) will result in the connection hanging if it receives a
-B<no_renegotiation> alert. OpenSSL versions 0.9.8m and later will regard
-a B<no_renegotiation> alert as fatal and respond with a fatal
-B<handshake_failure> alert. This is because the OpenSSL API currently has
-no provision to indicate to an application that a renegotiation attempt
-was refused.
-
=head2 Patched OpenSSL client and unpatched server.
If the option B<SSL_OP_LEGACY_SERVER_CONNECT> or
L<ssl(3)>, L<SSL_new(3)>, L<SSL_clear(3)>,
L<SSL_CTX_set_tmp_dh_callback(3)>,
-L<SSL_CTX_set_tmp_rsa_callback(3)>,
+L<SSL_CTX_set_min_proto_version(3)>,
L<dhparam(1)>
=head1 HISTORY
-B<SSL_OP_CIPHER_SERVER_PREFERENCE> and
-B<SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION> have been added in
-OpenSSL 0.9.7.
-
-B<SSL_OP_TLS_ROLLBACK_BUG> has been added in OpenSSL 0.9.6 and was automatically
-enabled with B<SSL_OP_ALL>. As of 0.9.7, it is no longer included in B<SSL_OP_ALL>
-and must be explicitly set.
-
-B<SSL_OP_DONT_INSERT_EMPTY_FRAGMENTS> has been added in OpenSSL 0.9.6e.
-Versions up to OpenSSL 0.9.6c do not include the countermeasure that
-can be disabled with this option (in OpenSSL 0.9.6d, it was always
-enabled).
-
-SSL_CTX_clear_options() and SSL_clear_options() were first added in OpenSSL
-0.9.8m.
-
-B<SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION>, B<SSL_OP_LEGACY_SERVER_CONNECT>
-and the function SSL_get_secure_renegotiation_support() were first added in
-OpenSSL 0.9.8m.
+The attempt to always try to use secure renegotiation was added in
+Openssl 0.9.8m.
=cut
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