ssl/t1_reneg.c

   1 /*
   2  * Copyright 1995-2016 The OpenSSL Project Authors. All Rights Reserved.
   3  *
   4  * Licensed under the OpenSSL license (the "License").  You may not use
   5  * this file except in compliance with the License.  You can obtain a copy
   6  * in the file LICENSE in the source distribution or at
   7  * https://www.openssl.org/source/license.html
   8  */
   9
  10 #include <stdio.h>
  11 #include <openssl/objects.h>
  12 #include "ssl_locl.h"
  13
  14 /* Add the server's renegotiation binding */
  15 int ssl_add_serverhello_renegotiate_ext(SSL *s, WPACKET *pkt)
  16 {
  17     if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_renegotiate)
  18             || !WPACKET_start_sub_packet_u16(pkt)
  19             || !WPACKET_start_sub_packet_u8(pkt)
  20             || !WPACKET_memcpy(pkt, s->s3->previous_client_finished,
  21                                s->s3->previous_client_finished_len)
  22             || !WPACKET_memcpy(pkt, s->s3->previous_server_finished,
  23                                s->s3->previous_server_finished_len)
  24             || !WPACKET_close(pkt)
  25             || !WPACKET_close(pkt))
  26         return 0;
  27
  28     return 1;
  29 }
  30
  31 /*
  32  * Parse the server's renegotiation binding and abort if it's not right
  33  */
  34 int ssl_parse_serverhello_renegotiate_ext(SSL *s, PACKET *pkt, int *al)
  35 {
  36     size_t expected_len = s->s3->previous_client_finished_len
  37         + s->s3->previous_server_finished_len;
  38     size_t ilen;
  39     const unsigned char *data;
  40
  41     /* Check for logic errors */
  42     OPENSSL_assert(!expected_len || s->s3->previous_client_finished_len);
  43     OPENSSL_assert(!expected_len || s->s3->previous_server_finished_len);
  44
  45     /* Parse the length byte */
  46     if (!PACKET_get_1_len(pkt, &ilen)) {
  47         SSLerr(SSL_F_SSL_PARSE_SERVERHELLO_RENEGOTIATE_EXT,
  48                SSL_R_RENEGOTIATION_ENCODING_ERR);
  49         *al = SSL_AD_ILLEGAL_PARAMETER;
  50         return 0;
  51     }
  52
  53     /* Consistency check */
  54     if (PACKET_remaining(pkt) != ilen) {
  55         SSLerr(SSL_F_SSL_PARSE_SERVERHELLO_RENEGOTIATE_EXT,
  56                SSL_R_RENEGOTIATION_ENCODING_ERR);
  57         *al = SSL_AD_ILLEGAL_PARAMETER;
  58         return 0;
  59     }
  60
  61     /* Check that the extension matches */
  62     if (ilen != expected_len) {
  63         SSLerr(SSL_F_SSL_PARSE_SERVERHELLO_RENEGOTIATE_EXT,
  64                SSL_R_RENEGOTIATION_MISMATCH);
  65         *al = SSL_AD_HANDSHAKE_FAILURE;
  66         return 0;
  67     }
  68
  69     if (!PACKET_get_bytes(pkt, &data, s->s3->previous_client_finished_len)
  70         || memcmp(data, s->s3->previous_client_finished,
  71                   s->s3->previous_client_finished_len) != 0) {
  72         SSLerr(SSL_F_SSL_PARSE_SERVERHELLO_RENEGOTIATE_EXT,
  73                SSL_R_RENEGOTIATION_MISMATCH);
  74         *al = SSL_AD_HANDSHAKE_FAILURE;
  75         return 0;
  76     }
  77
  78     if (!PACKET_get_bytes(pkt, &data, s->s3->previous_server_finished_len)
  79         || memcmp(data, s->s3->previous_server_finished,
  80                   s->s3->previous_server_finished_len) != 0) {
  81         SSLerr(SSL_F_SSL_PARSE_SERVERHELLO_RENEGOTIATE_EXT,
  82                SSL_R_RENEGOTIATION_MISMATCH);
  83         *al = SSL_AD_ILLEGAL_PARAMETER;
  84         return 0;
  85     }
  86     s->s3->send_connection_binding = 1;
  87
  88     return 1;
  89 }