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

Constify SSL_get_private_key().

PR#3106

Add callbacks supporting generation and retrieval of supplemental data entries, facilitating RFC 5878 (TLS auth extensions)
Removed prior audit proof logic - audit proof support was implemented using the generic TLS extension API
Tests exercising the new supplemental data registration and callback api can be found in ssltest.c.
Implemented changes to s_server and s_client to exercise supplemental data callbacks via the -auth argument, as well as additional flags to exercise supplemental data being sent only during renegotiation.

This change adds support for ALPN[1] in OpenSSL. ALPN is the IETF
blessed version of NPN and we'll be supporting both ALPN and NPN for
some time yet.

[1] https://tools.ietf.org/html/draft-ietf-tls-applayerprotoneg-00

Conflicts:
	ssl/ssl3.h
	ssl/t1_lib.c

Contributed by Trevor Perrin.

The only standard compression method is stateful and is incompatible with
DTLS.

Use the enc_flags field to determine whether we should use explicit IV,
signature algorithms or SHA256 default PRF instead of hard coding which
versions support each requirement.

new feature: if ctx==NULL in SSL_CTX_ctrl perform syntax checking only for some operations (currently curves and signature algorithms)

a ciphersuite to position the SCSV value in different places for testing
purposes.

client hello message. Previously this could only be retrieved on an initial
connection and it was impossible to determine the cipher IDs of any uknown
ciphersuites.

change the current certificate (in s->cert->key) to the one used and then
SSL_get_certificate and SSL_get_privatekey will automatically work.

right response is stapled. Also change SSL_get_certificate() so it
returns the certificate actually sent.  See
http://rt.openssl.org/Ticket/Display.html?id=2836.

perform sanity checks on server certificate type as soon as it is received instead of waiting until server key exchange

some invalid operations for testing purposes. Currently this can be used
to sign using digests the peer doesn't support, EC curves the peer
doesn't support and use certificates which don't match the type associated
with a ciphersuite.

by a certificate chain. Add additional tests to handle client
certificates: checks for matching certificate type and issuer name
comparison.

Print out results of checks for each candidate chain tested in
s_server/s_client.

that are disabled for this session (as opposed to always disabled by
configuration).

is required by client or server. An application can decide which
certificate chain to present based on arbitrary criteria: for example
supported signature algorithms. Add very simple example to s_server.
This fixes many of the problems and restrictions of the existing client
certificate callback: for example you can now clear existing certificates
and specify the whole chain.

the certificate can be used for (if anything). Set valid_flags field
in new tls1_check_chain function. Simplify ssl_set_cert_masks which used
to have similar checks in it.

Add new "cert_flags" field to CERT structure and include a "strict mode".
This enforces some TLS certificate requirements (such as only permitting
certificate signature algorithms contained in the supported algorithms
extension) which some implementations ignore: this option should be used
with caution as it could cause interoperability issues.

enabled instead of requiring an application to hard code a (possibly
inappropriate) parameter set and delve into EC internals we just
automatically use the preferred curve.

Tidy some code up.

Don't allocate a structure to handle ECC extensions when it is used for
default values.

Make supported curves configurable.

Add ctrls to retrieve shared curves: not fully integrated with rest of
ECC code yet.

Move new structure fields to end of structures.

certificate chain instead of an X509 structure.

This makes it easier to enhance code in future and the chain
output functions have access to the CERT_PKEY structure being
used.

The cipher definitions of these ciphersuites have been around since SSLeay
but were always disabled. Now OpenSSL supports DH certificates they can be
finally enabled.

Various additional changes were needed to make them work properly: many
unused fixed DH sections of code were untested.

Submitted by: Brian Carlstrom