generic-library/openssl
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

Fixes for the following claims:

Browse Source 
1) Certificate Message with no certs

  OpenSSL implementation sends the Certificate message during SSL
  handshake, however as per the specification, these have been omitted.

  -- RFC 2712 --
     CertificateRequest, and the ServerKeyExchange shown in Figure 1
     will be omitted since authentication and the establishment of a
     master secret will be done using the client's Kerberos credentials
     for the TLS server.  The client's certificate will be omitted for
     the same reason.
  -- RFC 2712 --

  3) Pre-master secret Protocol version

  The pre-master secret generated by OpenSSL does not have the correct
  client version.

  RFC 2712 says, if the Kerberos option is selected, the pre-master
  secret structure is the same as that used in the RSA case.

  TLS specification defines pre-master secret as:
         struct {
             ProtocolVersion client_version;
             opaque random[46];
         } PreMasterSecret;

  where client_version is the latest protocol version supported by the
  client

  The pre-master secret generated by OpenSSL does not have the correct
  client version. The implementation does not update the first 2 bytes
  of random secret for Kerberos Cipher suites. At the server-end, the
  client version from the pre-master secret is not validated.

PR: 1336
This commit is contained in:
Richard Levitte 2006-09-28 12:22:58 +00:00
parent 019bfef899
commit cbb92dfaf0
2 changed files with 28 additions and 6 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

6
ssl/s3_clnt.c
View File

@ -1902,8 +1902,10 @@ int ssl3_send_client_key_exchange(SSL *s)
n+=2;
}
if (RAND_bytes(tmp_buf,sizeof tmp_buf) <= 0)
goto err;
tmp_buf[0]=s->client_version>>8;
tmp_buf[1]=s->client_version&0xff;
if (RAND_bytes(&(tmp_buf[2]),sizeof tmp_buf-2) <= 0)
goto err;
/* 20010420 VRS. Tried it this way; failed.
** EVP_EncryptInit_ex(&ciph_ctx,enc, NULL,NULL);

28
ssl/s3_srvr.c
View File

@ -1,4 +1,4 @@
/* ssl/s3_srvr.c */
/* ssl/s3_srvr.c -*- mode:C; c-file-style: "eay" -*- */
/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
* All rights reserved.
*
@ -323,10 +323,11 @@ int ssl3_accept(SSL *s)
case SSL3_ST_SW_CERT_A:
case SSL3_ST_SW_CERT_B:
/* Check if it is anon DH or anon ECDH */
/* or normal PSK */
/* Check if it is anon DH or anon ECDH, */
/* normal PSK or KRB5 */
if (!(s->s3->tmp.new_cipher->algorithms & SSL_aNULL)
&& !(s->s3->tmp.new_cipher->algorithms & SSL_kPSK))
&& !(s->s3->tmp.new_cipher->algorithms & SSL_kPSK)
&& !(s->s3->tmp.new_cipher->algorithms & SSL_aKRB5))
{
ret=ssl3_send_server_certificate(s);
if (ret <= 0) goto end;
@ -2061,6 +2062,25 @@ int ssl3_get_client_key_exchange(SSL *s)
SSL_R_DATA_LENGTH_TOO_LONG);
goto err;
}
if (!((p[0] == (s->client_version>>8)) && (p[1] == (s->client_version & 0xff))))
{
/* The premaster secret must contain the same version number as the
* ClientHello to detect version rollback attacks (strangely, the
* protocol does not offer such protection for DH ciphersuites).
* However, buggy clients exist that send random bytes instead of
* the protocol version.
* If SSL_OP_TLS_ROLLBACK_BUG is set, tolerate such clients.
* (Perhaps we should have a separate BUG value for the Kerberos cipher)
*/
if (!((s->options & SSL_OP_TLS_ROLLBACK_BUG) &&
(p[0] == (s->version>>8)) && (p[1] == (s->version & 0xff))))
{
SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
SSL_AD_DECODE_ERROR);
goto err;
}
}
EVP_CIPHER_CTX_cleanup(&ciph_ctx);
s->session->master_key_length=