Commit 44191de2 authored by Matt Caswell's avatar Matt Caswell
Browse files

Send a protocol version alert 



If we fail to negotiate a version then we should send a protocol version
alert.

Fixes #3595

Reviewed-by: default avatarTim Hudson <tjh@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/3598)
parent fde111ba

ssl/s23_clnt.c

+28 −0
Original line number Diff line number Diff line
@@ -735,7 +735,35 @@ static int ssl23_get_server_hello(SSL *s) 
            s->version = TLS1_2_VERSION;

            s->method = TLSv1_2_client_method();

        } else {

            /*

             * Unrecognised version, we'll send a protocol version alert using

             * our preferred version.

             */

            switch(s->client_version) {

            default:

                /*

                 * Shouldn't happen

                 * Fall through

                 */

            case TLS1_2_VERSION:

                s->version = TLS1_2_VERSION;

                s->method = TLSv1_2_client_method();

                break;

            case TLS1_1_VERSION:

                s->version = TLS1_1_VERSION;

                s->method = TLSv1_1_client_method();

                break;

            case TLS1_VERSION:

                s->version = TLS1_VERSION;

                s->method = TLSv1_client_method();

                break;

            case SSL3_VERSION:

                s->version = SSL3_VERSION;

                s->method = SSLv3_client_method();

                break;

            }

            SSLerr(SSL_F_SSL23_GET_SERVER_HELLO, SSL_R_UNSUPPORTED_PROTOCOL);

            ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_PROTOCOL_VERSION);

            goto err;

        }