This patch makes the decoding of SSLv3 and TLS CBC records constant
time. Without this, a timing side-channel can be used to build a padding
oracle and mount Vaudenay's attack.
This patch also disables the stitched AESNI+SHA mode pending a similar
fix to that code.
In order to be easy to backport, this change is implemented in ssl/,
rather than as a generic AEAD mode. In the future this should be changed
around so that HMAC isn't in ssl/, but crypto/ as FIPS expects.
(cherry picked from commit e130841bcc)
Conflicts:
crypto/evp/c_allc.c
ssl/ssl_algs.c
ssl/ssl_locl.h
ssl/t1_enc.c
(cherry picked from commit 3622239826698a0e534dcf0473204c724bb9b4b4)
Conflicts:
ssl/d1_enc.c
ssl/s3_enc.c
ssl/s3_pkt.c
ssl/ssl3.h
ssl/ssl_algs.c
ssl/t1_enc.c
sure they are available in opensslconf.h, by giving them names starting
with "OPENSSL_" to avoid conflicts with other packages and by making
sure e_os2.h will cover all platform-specific cases together with
opensslconf.h.
I've checked fairly well that nothing breaks with this (apart from
external software that will adapt if they have used something like
NO_KRB5), but I can't guarantee it completely, so a review of this
change would be a good thing.