208a6012be
By using non-DER or invalid encodings outside the signed portion of a certificate the fingerprint can be changed without breaking the signature. Although no details of the signed portion of the certificate can be changed this can cause problems with some applications: e.g. those using the certificate fingerprint for blacklists. 1. Reject signatures with non zero unused bits. If the BIT STRING containing the signature has non zero unused bits reject the signature. All current signature algorithms require zero unused bits. 2. Check certificate algorithm consistency. Check the AlgorithmIdentifier inside TBS matches the one in the certificate signature. NB: this will result in signature failure errors for some broken certificates. 3. Check DSA/ECDSA signatures use DER. Reencode DSA/ECDSA signatures and compare with the original received signature. Return an error if there is a mismatch. This will reject various cases including garbage after signature (thanks to Antti Karjalainen and Tuomo Untinen from the Codenomicon CROSS program for discovering this case) and use of BER or invalid ASN.1 INTEGERs (negative or with leading zeroes). CVE-2014-8275 Reviewed-by: Emilia Käsper <emilia@openssl.org> (cherry picked from commit 684400ce192dac51df3d3e92b61830a6ef90be3e) Conflicts: CHANGES crypto/dsa/dsa_asn1.c
102 lines
4.2 KiB
C
102 lines
4.2 KiB
C
/* crypto/dsa/dsa_vrf.c */
|
|
/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
|
|
* All rights reserved.
|
|
*
|
|
* This package is an SSL implementation written
|
|
* by Eric Young (eay@cryptsoft.com).
|
|
* The implementation was written so as to conform with Netscapes SSL.
|
|
*
|
|
* This library is free for commercial and non-commercial use as long as
|
|
* the following conditions are aheared to. The following conditions
|
|
* apply to all code found in this distribution, be it the RC4, RSA,
|
|
* lhash, DES, etc., code; not just the SSL code. The SSL documentation
|
|
* included with this distribution is covered by the same copyright terms
|
|
* except that the holder is Tim Hudson (tjh@cryptsoft.com).
|
|
*
|
|
* Copyright remains Eric Young's, and as such any Copyright notices in
|
|
* the code are not to be removed.
|
|
* If this package is used in a product, Eric Young should be given attribution
|
|
* as the author of the parts of the library used.
|
|
* This can be in the form of a textual message at program startup or
|
|
* in documentation (online or textual) provided with the package.
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions
|
|
* are met:
|
|
* 1. Redistributions of source code must retain the copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
* 2. Redistributions in binary form must reproduce the above copyright
|
|
* notice, this list of conditions and the following disclaimer in the
|
|
* documentation and/or other materials provided with the distribution.
|
|
* 3. All advertising materials mentioning features or use of this software
|
|
* must display the following acknowledgement:
|
|
* "This product includes cryptographic software written by
|
|
* Eric Young (eay@cryptsoft.com)"
|
|
* The word 'cryptographic' can be left out if the rouines from the library
|
|
* being used are not cryptographic related :-).
|
|
* 4. If you include any Windows specific code (or a derivative thereof) from
|
|
* the apps directory (application code) you must include an acknowledgement:
|
|
* "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
|
|
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
|
|
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
|
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
|
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
|
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
|
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
|
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
|
* SUCH DAMAGE.
|
|
*
|
|
* The licence and distribution terms for any publically available version or
|
|
* derivative of this code cannot be changed. i.e. this code cannot simply be
|
|
* copied and put under another distribution licence
|
|
* [including the GNU Public Licence.]
|
|
*/
|
|
|
|
/* Original version from Steven Schoch <schoch@sheba.arc.nasa.gov> */
|
|
|
|
#include "cryptlib.h"
|
|
#include <openssl/dsa.h>
|
|
|
|
int DSA_do_verify(const unsigned char *dgst, int dgst_len, DSA_SIG *sig,
|
|
DSA *dsa)
|
|
{
|
|
return dsa->meth->dsa_do_verify(dgst, dgst_len, sig, dsa);
|
|
}
|
|
|
|
/* data has already been hashed (probably with SHA or SHA-1). */
|
|
/* returns
|
|
* 1: correct signature
|
|
* 0: incorrect signature
|
|
* -1: error
|
|
*/
|
|
int DSA_verify(int type, const unsigned char *dgst, int dgst_len,
|
|
const unsigned char *sigbuf, int siglen, DSA *dsa)
|
|
{
|
|
DSA_SIG *s;
|
|
const unsigned char *p = sigbuf;
|
|
unsigned char *der = NULL;
|
|
int derlen = -1;
|
|
int ret=-1;
|
|
|
|
s = DSA_SIG_new();
|
|
if (s == NULL) return(ret);
|
|
if (d2i_DSA_SIG(&s,&p,siglen) == NULL) goto err;
|
|
/* Ensure signature uses DER and doesn't have trailing garbage */
|
|
derlen = i2d_DSA_SIG(s, &der);
|
|
if (derlen != siglen || memcmp(sigbuf, der, derlen))
|
|
goto err;
|
|
ret=DSA_do_verify(dgst,dgst_len,s,dsa);
|
|
err:
|
|
if (derlen > 0)
|
|
{
|
|
OPENSSL_cleanse(der, derlen);
|
|
OPENSSL_free(der);
|
|
}
|
|
DSA_SIG_free(s);
|
|
return(ret);
|
|
}
|