Fix comments in ssltest.c: return value of 0 now means extension is
omitted and add_cb is not called for servers if the corresponding
extension is absent in ClientHello.

Test add_cb is not called if extension is not received.
Reviewed-by: NEmilia Käsper <emilia@openssl.org>

Reviewed-by: NEmilia Käsper <emilia@openssl.org>

Instead of SSL_CTX_set_custom_cli_ext and SSL_CTX_set_custom_srv_ext
use SSL_CTX_add_client_custom_ext and SSL_CTX_add_server_custom_ext.
Reviewed-by: NEmilia Käsper <emilia@openssl.org>

Support separate parse and add callback arguments.
Add new callback so an application can free extension data.
Change return value for send functions so < 0 is an error 0
omits extension and > 0 includes it. This is more consistent
with the behaviour of other functions in OpenSSL.

Modify parse_cb handling so <= 0 is an error.

Make SSL_CTX_set_custom_cli_ext and SSL_CTX_set_custom_cli_ext argument
order consistent.

NOTE: these changes WILL break existing code.

Remove (now inaccurate) in line documentation.
Reviewed-by: NEmilia Käsper <emilia@openssl.org>

Use "parse" and "add" for function and callback names instead of
"first" and "second".

Change arguments to callback so the extension type is unsigned int
and the buffer length is size_t. Note: this *will* break existing code.
Reviewed-by: NEmilia Käsper <emilia@openssl.org>

Reviewed-by: NEmilia Käsper <emilia@openssl.org>

Remove RFC5878 code. It is no longer needed for CT and has numerous bugs

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

The contract for custom extension callbacks has changed - all custom extension callbacks are triggered

Whitespace fixes

If multiple TLS extensions are expected but not received, the TLS extension and supplemental data 'generate' callbacks are the only chance for the receive-side to trigger a specific TLS alert during the handshake.

Removed logic which no-op'd TLS extension generate callbacks (as the generate callbacks need to always be called in order to trigger alerts), and updated the serverinfo-specific custom TLS extension callbacks to track which custom TLS extensions were received by the client, where no-ops for 'generate' callbacks are appropriate.

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.

Conflicts:
	ssl/ssltest.c

serverinfo rejects non-empty extensions.

Omit extension if no relevant serverinfo data.

Improve error-handling in serverinfo callback.

Cosmetic cleanups.

s_client documentation.

s_server documentation.

SSL_CTX_serverinfo documentation.

Cleaup -1 and NULL callback handling for custom extensions, add tests.

Cleanup ssl_rsa.c serverinfo code.

Whitespace cleanup.

Improve comments in ssl.h for serverinfo.

Whitespace.

Cosmetic cleanup.

Reject non-zero-len serverinfo extensions.

Whitespace.

Make it build.

Contributed by Trevor Perrin.

(cherry picked from commit cbf9b4aed3e209fe8a39e1d6f55aaf46d1369dc4)

Submitted by: Peter Sylvester <peter.sylvester@edelweb.fr>
Reviewed by: steve

Remove unnecessary code for srp and to add some comments to
s_client.

- the callback to provide a user during client connect is
no longer necessary since rfc 5054 a connection attempt
with an srp cipher and no user is terminated when the
cipher is acceptable

- comments to indicate in s_client the (non-)usefulness of
th primalaty tests for non known group parameters.

Fixes to make OpenSSL compile with no-rc4

Submitted by: steve@openssl.org

The original fix for PR#2125 broke compilation on some Unixware platforms:
revert and make conditional on VMS.

Submitted by: "Alon Bar-Lev" <alon.barlev@gmail.com>

Fix gcc-aix compilation issue.

deprecate the original (numeric-only) scheme, and replace with the
CRYPTO_THREADID object. This hides the platform-specifics and should reduce
the possibility for programming errors (where failing to explicitly check
both thread ID forms could create subtle, platform-specific bugs).

Thanks to Bodo, for invaluable review and feedback.

version some time soon.

to 'unsigned long' (ie. odd platforms/compilers), so a pointer-typed
version was added but it required portable code to check *both* modes to
determine equality. This commit maintains the availability of both thread
ID types, but deprecates the type-specific accessor APIs that invoke the
callbacks - instead a single type-independent API is used.  This simplifies
software that calls into this interface, and should also make it less
error-prone - as forgetting to call and compare *both* thread ID accessors
could have led to hard-to-debug/infrequent bugs (that might only affect
certain platforms or thread implementations). As the CHANGES note says,
there were corresponding deprecations and replacements in the
thread-related functions for BN_BLINDING and ERR too.

(draft-rescorla-tls-opaque-prf-input-00.txt), and do some cleanups and
bugfixes on the way.  In particular, this fixes the buffer bounds
checks in ssl_add_clienthello_tlsext() and in ssl_add_serverhello_tlsext().

Note that the opaque PRF Input TLS extension is not compiled by default;
see CHANGES.

Submitted by: Gisle Vanem

PR: 1191
Submitted by: Mika Kousa and Pasi Eronen of Nokia Corporation
Reviewed by: Nils Larsch