New functions to retrieve current certificate or private key
from an SSL_CTX.

Constify SSL_get_private_key().
(cherry picked from commit a25f9adc)

(cherry picked from commit 60aeb187)

(cherry picked from commit fdeaf55b)

PR#3106

If pointer comparison for current certificate fails check
to see if a match using X509_cmp succeeds for the current
certificate: this is useful for cases where the certificate
pointer is not available.
(cherry picked from commit 6856b288a6e66edd23907b7fa264f42e05ac9fc7)

PR#3169

This patch, which currently applies successfully against master and
1_0_2, adds the following functions:

SSL_[CTX_]select_current_cert() - set the current certificate without
disturbing the existing structure.

SSL_[CTX_]get0_chain_certs() - get the current certificate's chain.

SSL_[CTX_]clear_chain_certs() - clear the current certificate's chain.

The patch also adds these functions to, and fixes some existing errors
in, SSL_CTX_add1_chain_cert.pod.
(cherry picked from commit 2f56c9c015dbca45379c9a725915b3b8e765a119)

PR#3172
(cherry picked from commit 4f055e34c3598cad00fca097d812fa3e6436d967)

PR: 3165
Submitted by: Daniel Richard G.
(cherry picked from commit 2df9ec01)

PR: 3165

PR: 3165
(cherry picked from commit d1cf23ac)

(cherry picked from commit 16bc45ba)

(cherry picked from commit 08b433540416c5bc9a874ba0343e35ba490c65f1)

(cherry picked from commit 01be36ef70525e81fc358d2e559bdd0a0d9427a5)

(cherry picked from commit 7040d73d22987532faa503630d6616cf2788c975)

Add function to retrieve the signature from a CMS_SignerInfo structure:
applications can then read or modify it.
(cherry picked from commit e8df6cec4c09b9a94c4c07abcf0402d31ec82cc1)

Original definition depended on __LONG_MAX__ that is not guaranteed to
be present. As we don't support platforms with int narrower that 32 bits
it's appropriate to make defition inconditional.

PR: 3165
(cherry picked from commit 96180cac)

PR: 3165
(cherry picked from commit d24d1d7d)

Enable PSK ciphersuites with AES or DES3 in FIPS mode.
(cherry picked from commit e0ffd129)

<christian@python.org>.

(cherry picked from commit 96e16bdd)

(cherry picked from commit c557f921)

(cherry picked from commit abf840e4)

(cherry picked from commit 27f3b65f)

Extend SSL_CONF to return command value types.

Add certificate and key options.

Update documentation.
(cherry picked from commit ec2f7e56)

(cherry picked from commit 13af1451)

Don't require a public key in tls1_set_ec_id if compression status is
not needed. This fixes a bug where SSL_OP_SINGLE_ECDH_USE wouldn't work.

Add -ecdh_single option to set SSL_OP_SINGLE_ECDH_USE on the command line.

PR: 2809

DTLS/SCTP requires DATA and FORWARD-TSN chunks to be protected with
SCTP-AUTH.  It is checked if this has been activated successfully for
the local and remote peer. Due to a bug, however, the
gauth_number_of_chunks field of the authchunks struct is missing on
FreeBSD, and was therefore not considered in the OpenSSL implementation.
This patch sets the corresponding pointer for the check correctly
whether or not this bug is present.

PR: 2808

With DTLS/SCTP the SCTP extension SCTP-AUTH is used to protect DATA and
FORWARD-TSN chunks. The key for this extension is derived from the
master secret and changed with the next ChangeCipherSpec, whenever a new
key has been negotiated. The following Finished then already uses the
new key.  Unfortunately, the ChangeCipherSpec and Finished are part of
the same flight as the ClientKeyExchange, which is necessary for the
computation of the new secret. Hence, these messages are sent
immediately following each other, leaving the server very little time to
compute the new secret and pass it to SCTP before the finished arrives.
So the Finished is likely to be discarded by SCTP and a retransmission
becomes necessary. To prevent this issue, the Finished of the client is
still sent with the old key.

Instead, send random bytes, unless SSL_SEND_{CLIENT,SERVER}RANDOM_MODE
is set.

This is a forward-port of commits:
  4af79303
  f4c93b46
  3da721da
  25832701

While the gmt_unix_time record was added in an ostensible attempt to
mitigate the dangers of a bad RNG, its presence leaks the host's view
of the current time in the clear.  This minor leak can help
fingerprint TLS instances across networks and protocols... and what's
worse, it's doubtful thet the gmt_unix_time record does any good at
all for its intended purpose, since:

    * It's quite possible to open two TLS connections in one second.

    * If the PRNG output is prone to repeat itself, ephemeral
      handshakes (and who knows what else besides) are broken.