Add description of "allocate and encode" operation for ASN1 routines.

Document how versioning will for after the letter release reaches
y.

The version check for DTLS1_VERSION was redundant as
DTLS1_VERSION > TLS1_1_VERSION, however we do need to
check for DTLS1_BAD_VER for compatibility.

PR:2984

(cherry picked from commit cbf9b4ae)

(cherry picked from commit f88dbb83)

It also ensures that valgring is happy.

Revert is appropriate because binary compatibility is not an issue
in 1.1.

MD5 should use little endian order. Fortunately the only ciphersuite
affected is EXP-RC2-CBC-MD5 (TLS_RSA_EXPORT_WITH_RC2_CBC_40_MD5) which
is a rarely used export grade ciphersuite.
(cherry picked from commit f306b87d)

(cherry picked from commit 529d27ea)

Address CBC decrypt timing issues and reenable the AESNI+SHA1 stitch.
(cherry picked from commit 125093b5)

Kludge alert. This is arranged by passing padding length in unused
bits of SSL3_RECORD->type, so that orig_len can be reconstructed.
(cherry picked from commit 8bfd4c65)

(cherry picked from commit 04e45b52)

(cherry picked from commit d5371324)

RISCs are picky and alignment granted by compiler for md_state can be
insufficient for SHA512.
(cherry picked from commit 36260233)

Break dependency on uint64_t. It's possible to declare bits as
unsigned int, because TLS packets are limited in size and 32-bit
value can't overflow.
(cherry picked from commit cab13fc8)

(cherry picked from commit 34ab3c8c)

branches it needs to be in a "gap".
(cherry picked from commit 81ce0e14)

We have to use EVP in FIPS mode so we can only partially mitigate
timing differences.

Make an extra call to EVP_DigestSignUpdate to hash additonal blocks
to cover any timing differences caused by removal of padding.
(cherry picked from commit b908e88e)

(cherry picked from commit 014265eb)

This change updates the DTLS code to match the constant-time CBC
behaviour in the TLS.
(cherry picked from commit 9f27de17)

The previous CBC patch was bugged in that there was a path through enc()
in s3_pkt.c/d1_pkt.c which didn't set orig_len. orig_len would be left
at the previous value which could suggest that the packet was a
sufficient length when it wasn't.
(cherry picked from commit 6cb19b76)

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 e130841b)

This change adds CRYPTO_memcmp, which compares two vectors of bytes in
an amount of time that's independent of their contents. It also changes
several MAC compares in the code to use this over the standard memcmp,
which may leak information about the size of a matching prefix.
(cherry picked from commit 2ee79888)

encrypted premaster secret value.

PR: 2963 and a number of others

PR: 2963 and a number of others