openssl-security2.patch

   1 --- ssl/s3_srvr.c       29 Nov 2002 11:31:51 -0000      1.85.2.14
   2 +++ ssl/s3_srvr.c       19 Mar 2003 18:00:00 -0000
   3 @@ -1447,7 +1447,7 @@
   4                 if (i != SSL_MAX_MASTER_KEY_LENGTH)
   5                         {
   6                         al=SSL_AD_DECODE_ERROR;
   7 -                       SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,SSL_R_BAD_RSA_DECRYPT);
   8 +                       /* SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,SSL_R_BAD_RSA_DECRYPT); */
   9                         }
  10
  11                 if ((al == -1) && !((p[0] == (s->client_version>>8)) && (p[1] == (s->client_version & 0xff))))
  12 @@ -1463,30 +1463,29 @@
  13                                 (p[0] == (s->version>>8)) && (p[1] == (s->version & 0xff))))
  14                                 {
  15                                 al=SSL_AD_DECODE_ERROR;
  16 -                               SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,SSL_R_BAD_PROTOCOL_VERSION_NUMBER);
  17 -                               goto f_err;
  18 +                               /* SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,SSL_R_BAD_PROTOCOL_VERSION_NUMBER); */
  19 +
  20 +                               /* The Klima-Pokorny-Rosa extension of Bleichenbacher's attack
  21 +                                * (http://eprint.iacr.org/2003/052/) exploits the version
  22 +                                * number check as a "bad version oracle" -- an alert would
  23 +                                * reveal that the plaintext corresponding to some ciphertext
  24 +                                * made up by the adversary is properly formatted except
  25 +                                * that the version number is wrong.  To avoid such attacks,
  26 +                                * we should treat this just like any other decryption error. */
  27 +                               p[0] = (char)(int) "CAN-2003-0131 patch 2003-03-19";
  28                                 }
  29                         }
  30
  31                 if (al != -1)
  32                         {
  33 -#if 0
  34 -                       goto f_err;
  35 -#else
  36                         /* Some decryption failure -- use random value instead as countermeasure
  37                          * against Bleichenbacher's attack on PKCS #1 v1.5 RSA padding
  38 -                        * (see RFC 2246, section 7.4.7.1).
  39 -                        * But note that due to length and protocol version checking, the
  40 -                        * attack is impractical anyway (see section 5 in D. Bleichenbacher:
  41 -                        * "Chosen Ciphertext Attacks Against Protocols Based on the RSA
  42 -                        * Encryption Standard PKCS #1", CRYPTO '98, LNCS 1462, pp. 1-12).
  43 -                        */
  44 +                        * (see RFC 2246, section 7.4.7.1). */
  45                         ERR_clear_error();
  46                         i = SSL_MAX_MASTER_KEY_LENGTH;
  47                         p[0] = s->client_version >> 8;
  48                         p[1] = s->client_version & 0xff;
  49                         RAND_pseudo_bytes(p+2, i-2); /* should be RAND_bytes, but we cannot work around a failure */
  50 -#endif
  51                         }
  52
  53                 s->session->master_key_length=