Allow setting of security level in cipher string using the
@SECLEVEL=N syntax.

Since ssltest needs to test low security ciphersuites and keys
set security level to zero so they aren't rejected.

Add a debugging security callback option to s_client/s_server. This will
print out each security parameter as it is accepted or rejected.

Security callback: selects which parameters are permitted including
sensible defaults based on bits of security.

The "parameters" which can be selected include: ciphersuites,
curves, key sizes, certificate signature algorithms, supported
signature algorithms, DH parameters, SSL/TLS version, session tickets
and compression.

In some cases prohibiting the use of a parameters will mean they are
not advertised to the peer: for example cipher suites and ECC curves.
In other cases it will abort the handshake: e.g DH parameters or the
peer key size.

Documentation to follow...

New function ssl_cipher_disabled.

Check for disabled client ciphers using ssl_cipher_disabled.

New function to return only supported ciphers.

New option to ciphers utility to print only supported ciphers.

Add auto DH parameter support. This is roughly equivalent to the
ECDH auto curve selection but for DH. An application can just call

SSL_CTX_set_auto_dh(ctx, 1);

and appropriate DH parameters will be used based on the size of the
server key.

Unlike ECDH there is no way a peer can indicate the range of DH parameters
it supports. Some peers cannot handle DH keys larger that 1024 bits for
example. In this case if you call:

SSL_CTX_set_auto_dh(ctx, 2);

Only 1024 bit DH parameters will be used.

If the server key is 7680 bits or more in size then 8192 bit DH parameters
will be used: these will be *very* slow.

The old export ciphersuites aren't supported but those are very
insecure anyway.

Add functions to return the "bits of security" for various public key
algorithms. Based on SP800-57.

(cherry picked from commit bc5ec653)

(cherry picked from commit 1f44dac24d1cb752b1a06be9091bb03a88a8598e)

Don't clear verification errors from the error queue unless
SSL_BUILD_CHAIN_FLAG_CLEAR_ERROR is set.

If errors occur during verification and SSL_BUILD_CHAIN_FLAG_IGNORE_ERROR
is set return 2 so applications can issue warnings.
(cherry picked from commit 2dd6976f)

Some CMS SignedData structure use a signature algorithm OID such
as SHA1WithRSA instead of the RSA algorithm OID. Workaround this
case by tolerating the signature if we recognise the OID.

Use a previously unused value as we will be updating multiple released
branches.
(cherry picked from commit 0737acd2)

Fix for the attack described in the paper "Recovering OpenSSL
ECDSA Nonces Using the FLUSH+RELOAD Cache Side-channel Attack"
by Yuval Yarom and Naomi Benger. Details can be obtained from:
http://eprint.iacr.org/2014/140

Thanks to Yuval Yarom and Naomi Benger for discovering this
flaw and to Yuval Yarom for supplying a fix.
(cherry picked from commit 2198be34)

Conflicts:

	CHANGES

(cherry picked from commit 7a3e67f029969620966b8a627b8485d83692cca5)

PR: 3275

The problem is that OpenSSH calls EVP_Cipher, which is not as
protective as EVP_CipherUpdate. Formally speaking we ought to
do more checks in *_cipher methods, including rejecting
lengths not divisible by block size (unless ciphertext stealing
is in place). But for now I implement check for zero length in
low-level based on precedent.

PR: 3087, 2775

Submitted by: Roumen Petrov

Submitted by: Roumen Petrov

(cherry picked from commit bdfc0e28)

Add option to set an alternative to the default hmacWithSHA1 PRF
for PKCS#8 private key encryptions. This is used automatically
by PKCS8_encrypt if the nid specified is a PRF.

Add option to pkcs8 utility.

Update docs.
(cherry picked from commit b60272b0)

(cherry picked from commit 124d2188)

Although the memory allocated by compression methods is fixed and
cannot grow over time it can cause warnings in some leak checking
tools. The function SSL_COMP_free_compression_methods() will free
and zero the list of supported compression methods. This should
*only* be called in a single threaded context when an application
is shutting down to avoid interfering with existing contexts
attempting to look up compression methods.
(cherry picked from commit 976c5830)

PR: 3271

(cherry picked from commit 3eddd1706a30cdf3dc9278692d8ee9038eac8a0d)