Revise DTLS code. There was a *lot* of code duplication in the
DTLS code that generates records. This makes it harder to maintain and
sometimes a TLS update is omitted by accident from the DTLS code.

Specifically almost all of the record generation functions have code like
this:

some_pointer = buffer + HANDSHAKE_HEADER_LENGTH;
... Record creation stuff ...
set_handshake_header(ssl, SSL_MT_SOMETHING, message_len);

...

write_handshake_message(ssl);

Where the "Record creation stuff" is identical between SSL/TLS and DTLS or
in some cases has very minor differences.

By adding a few fields to SSL3_ENC to include the header length, some flags
and function pointers for handshake header setting and handshake writing the
code can cope with both cases.

Note: although this passes "make test" and some simple DTLS tests there may
be some minor differences in the DTLS code that have to be accounted for.

Submitted by: Robin Seggelmann <seggelmann@fh-muenster.de>

Fix possible DTLS timer deadlock.

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.

Submitted by: Robin Seggelmann <seggelmann@fh-muenster.de>
Reviewed by: steve

Support for TLS/DTLS heartbeats.

Submitted by: Robin Seggelmann <seggelmann@fh-muenster.de>
Reviewed by: steve

Add SCTP support for DTLS (RFC 6083).

Submitted by: Robin Seggelmann <seggelmann@fh-muenster.de>
Reviewed by: steve

Fix DTLS session resumption timer bug.

is picked up.

Submitted By: Robin Seggelmann <seggelmann@fh-muenster.de>

Support for abbreviated handshakes when renegotiating.

Submitted by: steve@openssl.org

More robust fix and workaround for PR#1949. Don't try to work out if there
is any write pending data as this can be unreliable: always flush.

Submitted by: Robin Seggelmann <seggelmann@fh-muenster.de>

Add extension support to DTLS code mainly using existing implementation for
TLS.

Submitted by: Robin Seggelmann <seggelmann@fh-muenster.de>
Approved by: steve@openssl.org

Add Renegotiation extension to DTLS, fix DTLS ClientHello processing bug.

Fix from 0.9.8-stable.

OPENSSL_NO_DEPRECATED, etc. Steve, please double-check the CMS stuff...

HelloVerifyRequest.

Submitted by: Victor B. Wagner <vitus@cryptocom.ru>

ciphersuite selection code in HEAD

Submitted by: Victor Duchovni

This change resolves a number of problems and obviates multiple kludges.
A new feature is that you can now say "AES256" or "AES128" (not just
"AES", which enables both).

In some cases the ciphersuite list generated from a given string is
affected by this change.  I hope this is just in those cases where the
previous behaviour did not make sense.

pointer and make the SSL_METHOD parameter in SSL_CTX_new,
SSL_CTX_set_ssl_version and SSL_set_ssl_method const.

for locking code. The CRYPTO_LOCK_SSL_METHOD lock is now no longer used.

    	./configure no-deprecated [no-dsa] [no-dh] [no-ec] [no-rsa]
    	make depend all test
work again

PR: 1159

with the SSL_OP_NO_SSLv2 option.

move some functions from exported header <openssl/dtl1.h> into "ssl_locl.h";
fix silly indentation (a TAB is *not* always 4 spaces)