Commit 2ee1271d authored by Matt Caswell's avatar Matt Caswell
Browse files

Ensure the whole key_share extension is well formatted 



Reviewed-by: default avatarRich Salz <rsalz@openssl.org>
parent ef7daaf9

ssl/t1_lib.c

+12 −2
Original line number Diff line number Diff line
@@ -2318,7 +2318,7 @@ static int ssl_scan_clienthello_tlsext(SSL *s, CLIENTHELLO_MSG *hello, int *al) 
            PACKET key_share_list, encoded_pt;

            const unsigned char *curves;

            size_t num_curves;

            int group_nid;

            int group_nid, found = 0;

            unsigned int curve_flags;



            /* Sanity check */
@@ -2338,13 +2338,21 @@ static int ssl_scan_clienthello_tlsext(SSL *s, CLIENTHELLO_MSG *hello, int *al) 
            while (PACKET_remaining(&key_share_list) > 0) {

                if (!PACKET_get_net_2(&key_share_list, &group_id)

                        || !PACKET_get_length_prefixed_2(&key_share_list,

                                                         &encoded_pt)) {

                                                         &encoded_pt)

                        || PACKET_remaining(&encoded_pt) == 0) {

                    *al = SSL_AD_HANDSHAKE_FAILURE;

                    SSLerr(SSL_F_SSL_SCAN_CLIENTHELLO_TLSEXT,

                           SSL_R_LENGTH_MISMATCH);

                    return 0;

                }



                /*

                 * If we already found a suitable key_share we loop through the

                 * rest to verify the structure, but don't process them.

                 */

                if (found)

                    continue;



                /* Check this share is in supported_groups */

                if (!tls1_get_curvelist(s, 1, &curves, &num_curves)) {

                    *al = SSL_AD_INTERNAL_ERROR;
@@ -2416,6 +2424,8 @@ static int ssl_scan_clienthello_tlsext(SSL *s, CLIENTHELLO_MSG *hello, int *al) 
                    SSLerr(SSL_F_SSL_SCAN_CLIENTHELLO_TLSEXT, SSL_R_BAD_ECPOINT);

                    return 0;

                }



                found = 1;

            }

        }

        /*