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 684400ce19)
Conflicts:
CHANGES
crypto/dsa/dsa_asn1.c
Submitted by: steve@openssl.org
Fix to make DHparams_dup() et al work in C++.
For 1.0 fix the final argument to ASN1_dup() so it is void *. Replace some
*_dup macros with functions.
knock-on work than expected - they've been extracted into a patch
series that can be completed elsewhere, or in a different branch,
before merging back to HEAD.
deprecate the original (numeric-only) scheme, and replace with the
CRYPTO_THREADID object. This hides the platform-specifics and should reduce
the possibility for programming errors (where failing to explicitly check
both thread ID forms could create subtle, platform-specific bugs).
Thanks to Bodo, for invaluable review and feedback.
to 'unsigned long' (ie. odd platforms/compilers), so a pointer-typed
version was added but it required portable code to check *both* modes to
determine equality. This commit maintains the availability of both thread
ID types, but deprecates the type-specific accessor APIs that invoke the
callbacks - instead a single type-independent API is used. This simplifies
software that calls into this interface, and should also make it less
error-prone - as forgetting to call and compare *both* thread ID accessors
could have led to hard-to-debug/infrequent bugs (that might only affect
certain platforms or thread implementations). As the CHANGES note says,
there were corresponding deprecations and replacements in the
thread-related functions for BN_BLINDING and ERR too.
of handshake failure
2. Changes to x509_certificate_type function (crypto/x509/x509type.c) to
make it recognize GOST certificates as EVP_PKT_SIGN|EVP_PKT_EXCH
(required for s3_srvr to accept GOST client certificates).
3. Changes to EVP
- adding of function EVP_PKEY_CTX_get0_peerkey
- Make function EVP_PKEY_derive_set_peerkey work for context with
ENCRYPT operation, because we use peerkey field in the context to
pass non-ephemeral secret key to GOST encrypt operation.
- added EVP_PKEY_CTRL_SET_IV control command. It is really
GOST-specific, but it is used in SSL code, so it has to go
in some header file, available during libssl compilation
4. Fix to HMAC to avoid call of OPENSSL_cleanse on undefined data
5. Include des.h if KSSL_DEBUG is defined into some libssl files, to
make debugging output which depends on constants defined there, work
and other KSSL_DEBUG output fixes
6. Declaration of real GOST ciphersuites, two authentication methods
SSL_aGOST94 and SSL_aGOST2001 and one key exchange method SSL_kGOST
7. Implementation of these methods.
8. Support for sending unsolicited serverhello extension if GOST
ciphersuite is selected. It is require for interoperability with
CryptoPro CSP 3.0 and 3.6 and controlled by
SSL_OP_CRYPTOPRO_TLSEXT_BUG constant.
This constant is added to SSL_OP_ALL, because it does nothing, if
non-GOST ciphersuite is selected, and all implementation of GOST
include compatibility with CryptoPro.
9. Support for CertificateVerify message without length field. It is
another CryptoPro bug, but support is made unconditional, because it
does no harm for draft-conforming implementation.
10. In tls1_mac extra copy of stream mac context is no more done.
When I've written currently commited code I haven't read
EVP_DigestSignFinal manual carefully enough and haven't noticed that
it does an internal digest ctx copying.
This implementation was tested against
1. CryptoPro CSP 3.6 client and server
2. Cryptopro CSP 3.0 server
