NAME

       SSL_CTX_set_min_proto_version, SSL_CTX_set_max_proto_version,
       SSL_CTX_get_min_proto_version, SSL_CTX_get_max_proto_version, SSL_set_min_proto_version,
       SSL_set_max_proto_version, SSL_get_min_proto_version, SSL_get_max_proto_version - Get and
       set minimum and maximum supported protocol version

SYNOPSIS

        #include <openssl/ssl.h>

        int SSL_CTX_set_min_proto_version(SSL_CTX *ctx, int version);
        int SSL_CTX_set_max_proto_version(SSL_CTX *ctx, int version);
        int SSL_CTX_get_min_proto_version(SSL_CTX *ctx);
        int SSL_CTX_get_max_proto_version(SSL_CTX *ctx);

        int SSL_set_min_proto_version(SSL *ssl, int version);
        int SSL_set_max_proto_version(SSL *ssl, int version);
        int SSL_get_min_proto_version(SSL *ssl);
        int SSL_get_max_proto_version(SSL *ssl);

DESCRIPTION

       The functions get or set the minimum and maximum supported protocol versions for the ctx
       or ssl.  This works in combination with the options set via SSL_CTX_set_options(3) that
       also make it possible to disable specific protocol versions.  Use these functions instead
       of disabling specific protocol versions.

       Setting the minimum or maximum version to 0, will enable protocol versions down to the
       lowest version, or up to the highest version supported by the library, respectively.

       Getters return 0 in case ctx or ssl have been configured to automatically use the lowest
       or highest version supported by the library.

       Currently supported versions are SSL3_VERSION, TLS1_VERSION, TLS1_1_VERSION,
       TLS1_2_VERSION, TLS1_3_VERSION for TLS and DTLS1_VERSION, DTLS1_2_VERSION for DTLS.

RETURN VALUES

       These setter functions return 1 on success and 0 on failure. The getter functions return
       the configured version or 0 for auto-configuration of lowest or highest protocol,
       respectively.

NOTES

       All these functions are implemented using macros.

SEE ALSO

       ssl(7), SSL_CTX_set_options(3), SSL_CONF_cmd(3)

HISTORY

       The setter functions were added in OpenSSL 1.1.0. The getter functions were added in
       OpenSSL 1.1.1.

COPYRIGHT

       Copyright 2016-2019 The OpenSSL Project Authors. All Rights Reserved.

       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 <https://www.openssl.org/source/license.html>.