From bfc19297cddd5bc2192c02c7f8896d804b0456cb Mon Sep 17 00:00:00 2001 From: Rich Salz Date: Fri, 9 Oct 2015 14:14:34 -0400 Subject: [PATCH] Avoid SHA1 weakness In X509_cmp, if cert digest is equal, look at DER of the signed part. This is what master and 1.0.2 already do. Reviewed-by: Dr. Stephen Henson --- crypto/x509/x509_cmp.c | 15 ++++++++++++++- 1 file changed, 14 insertions(+), 1 deletion(-) diff --git a/crypto/x509/x509_cmp.c b/crypto/x509/x509_cmp.c index 3c5b717c15..5792e7f51d 100644 --- a/crypto/x509/x509_cmp.c +++ b/crypto/x509/x509_cmp.c @@ -179,11 +179,24 @@ unsigned long X509_subject_name_hash_old(X509 *x) */ int X509_cmp(const X509 *a, const X509 *b) { + int rv; + /* ensure hash is valid */ X509_check_purpose((X509 *)a, -1, 0); X509_check_purpose((X509 *)b, -1, 0); - return memcmp(a->sha1_hash, b->sha1_hash, SHA_DIGEST_LENGTH); + rv = memcmp(a->sha1_hash, b->sha1_hash, SHA_DIGEST_LENGTH); + if (rv) + return rv; + /* Check for match against stored encoding too */ + if (!a->cert_info->enc.modified && !b->cert_info->enc.modified) { + rv = (int)(a->cert_info->enc.len - b->cert_info->enc.len); + if (rv) + return rv; + return memcmp(a->cert_info->enc.enc, b->cert_info->enc.enc, + a->cert_info->enc.len); + } + return rv; } #endif -- 2.25.1