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>
According to X6.90 null, object identifier, boolean, integer and enumerated
types can only have primitive encodings: return an error if any of
these are received with a constructed encoding.
Reviewed-by: Emilia Käsper <emilia@openssl.org>
i2d_re_X509_tbs re-encodes the TBS portion of the certificate.
Reviewed-by: Rich Salz <rsalz@openssl.org>
Reviewed-by: Dr Stephen Henson <steve@openssl.org>
Add a dozen more const declarations where appropriate.
These are from Justin; while adding his patch, I noticed
ASN1_BIT_STRING_check could be fixed, too.
Reviewed-by: Dr. Stephen Henson <steve@openssl.org>
- Upon parsing, reject OIDs with invalid base-128 encoding.
- Always NUL-terminate the destination buffer in OBJ_obj2txt printing function.
CVE-2014-3508
Reviewed-by: Dr. Stephen Henson <steve@openssl.org>
Reviewed-by: Kurt Roeckx <kurt@openssl.org>
Reviewed-by: Tim Hudson <tjh@openssl.org>
If the oid parameter is set to NULL in X509_add1_trust_object
create an empty list of trusted purposes corresponding to
"no purpose" if trust is checked.
Add X9.42 DH KDF. Move sharedinfo generation code to CMS library as the
same structure is used by DH and ECDH.
Move ASN1_OBJECT typedef to ossl_typ.h so it can be picked up by dh headers
without the need to use ASN1.
If an ASN1_INTEGER structure is allocated but not explicitly set encode
it as zero: don't generate an invalid zero length INTEGER.
(cherry picked from commit 1643edc63c)
