Reviewed-by: NRichard Levitte <levitte@openssl.org>

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 2ee798880a246d648ecddadc5b91367bee4a5d98)

but used in the code.

test for them!

Check if IDEA is being built or not.
This is part of a large change submitted by Markus Friedl <markus@openbsd.org>

Important SSL 2.0 bugfixes (bugs found while implementing msg_callback).

reveal whether illegal block cipher padding was found or a MAC
verification error occured.

In ssl/s2_pkt.c, verify that the purported number of padding bytes is in
the legal range.

missed any.

This compiles and runs on Linux, and external applications have no
problems with it.  The definite test will be to build this on VMS.

as a shared library without RSA.  Use #ifndef NO_SSL2 instead of
NO_RSA in ssl/s2*.c.

Submitted by: Kris Kennaway <kris@hub.freebsd.org>
Modified by Ulf Möller

SSL_MODE_ENABLE_PARTIAL_WRITE, SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER.

Submitted by:
Reviewed by:
PR: