The function tls_process_key_exchange() is too long. This commit moves
the PSK preamble processing out to a separate function.
Reviewed-by: NRichard Levitte <levitte@openssl.org>

Narrow the scope of the local vars in preparation for split up this
function.
Reviewed-by: NRichard Levitte <levitte@openssl.org>

If the SSL_SESS_CACHE_NO_INTERNAL_STORE cache mode is used then we weren't
removing sessions from the external cache, e.g. if an alert occurs the
session is supposed to be automatically removed.
Reviewed-by: NRichard Levitte <levitte@openssl.org>

Reviewed-by: NRich Salz <rsalz@openssl.org>

Reviewed-by: NRichard Levitte <levitte@openssl.org>

Reviewed-by: NRichard Levitte <levitte@openssl.org>

Continuing previous commit to break up the
tls_construct_client_key_exchange() function. This splits out the SRP
code.
Reviewed-by: NRichard Levitte <levitte@openssl.org>

Continuing previous commit to break up the
tls_construct_client_key_exchange() function. This splits out the GOST
code.
Reviewed-by: NRichard Levitte <levitte@openssl.org>

Continuing previous commit to break up the
tls_construct_client_key_exchange() function. This splits out the ECDHE
code.
Reviewed-by: NRichard Levitte <levitte@openssl.org>

Continuing previous commit to break up the
tls_construct_client_key_exchange() function. This splits out the DHE
code.
Reviewed-by: NRichard Levitte <levitte@openssl.org>

The tls_construct_client_key_exchange() function is too long. This splits
out the construction of the PSK pre-amble into a separate function as well
as the RSA construction.
Reviewed-by: NRichard Levitte <levitte@openssl.org>

This is in preparation for splitting up this over long function.
Reviewed-by: NRichard Levitte <levitte@openssl.org>

The static function key_exchange_expected() used to return -1 on error.
Commit 361a1191 changed that so that it can never fail. This means that
some tidy up can be done to simplify error handling in callers of that
function.
Reviewed-by: NEmilia Käsper <emilia@openssl.org>

In TLS if the server sends a CertificateRequest and the client does not
provide one, if the server cannot continue it should send a
HandshakeFailure alert. In SSLv3 the same should happen, but instead we
were sending an UnexpectedMessage alert. This is incorrect - the message
isn't unexpected - it is valid for the client not to send one - its just
that we cannot continue without one.
Reviewed-by: NEmilia Käsper <emilia@openssl.org>

Move the preparation of the client certificate to be post processing work
after reading the CertificateRequest message rather than pre processing
work prior to writing the Certificate message. As part of preparing the
client certificate we may discover that we do not have one available. If
we are also talking SSLv3 then we won't send the Certificate message at
all. However, if we don't discover this until we are about to send the
Certificate message it is too late and we send an empty one anyway. This
is wrong for SSLv3.
Reviewed-by: NEmilia Käsper <emilia@openssl.org>

Reviewed-by: NRichard Levitte <levitte@openssl.org>

The set0 setters take ownership of their arguments, so the values should
be set to NULL to avoid a double-free in the cleanup block should
ssl_security(SSL_SECOP_TMP_DH) fail. Found by BoringSSL's WeakDH test.
Reviewed-by: NKurt Roeckx <kurt@openssl.org>
Reviewed-by: NRich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/1299)

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

Reviewed-by: NKurt Roeckx <kurt@openssl.org>
Reviewed-by: NMatt Caswell <matt@openssl.org>

The ssl3_init_finished_mac() function can fail, in which case we need to
propagate the error up through the stack.

RT#3198
Reviewed-by: NRich Salz <rsalz@openssl.org>

The write BIO for handshake messages is bufferred so that we only write
out to the network when we have a complete flight. There was some
complexity in the buffering logic so that we switched buffering on and
off at various points through out the handshake. The only real reason to
do this was historically it complicated the state machine when you wanted
to flush because you had to traverse through the "flush" state (in order
to cope with NBIO). Where we knew up front that there was only going to
be one message in the flight we switched off buffering to avoid that.

In the new state machine there is no longer a need for a flush state so
it is simpler just to have buffering on for the whole handshake. This
also gives us the added benefit that we can simply call flush after every
flight even if it only has one message in it. This means that BIO authors
can implement their own buffering strategies and not have to be aware of
the state of the SSL object (previously they would have to switch off
their own buffering during the handshake because they could not rely on
a flush being received when they really needed to write data out). This
last point addresses GitHub Issue #322.
Reviewed-by: NAndy Polyakov <appro@openssl.org>

Reviewed-by: NRichard Levitte <levitte@openssl.org>
Reviewed-by: NKurt Roeckx <kurt@openssl.org>

Fix various references to s3_clnt.c and s3_srvr.c which don't exist
any more.

GitHub Issue #765
Reviewed-by: NRichard Levitte <levitte@openssl.org>

Per RFC 4507, section 3.3:

   This message [NewSessionTicket] MUST be sent if the
   server included a SessionTicket extension in the ServerHello.  This
   message MUST NOT be sent if the server did not include a
   SessionTicket extension in the ServerHello.

The presence of the NewSessionTicket message should be determined
entirely from the ServerHello without probing.

RT#4389
Reviewed-by: NEmilia Käsper <emilia@openssl.org>
Reviewed-by: NMatt Caswell <matt@openssl.org>

The tls_client_key_exchange_post_work() frees the pms on error. It also
calls ssl_generate_master_secret() which also free the pms. If an error
occurs after ssl_generate_master_secret() has been called then a double
free can occur.
Reviewed-by: NAndy Polyakov <appro@openssl.org>

Reviewed-by: NRichard Levitte <levitte@openssl.org>
Reviewed-by: NRich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/952)

If we fail halfway through constructing the peer_tmp EVP_PKEY but we have
already stored it in s->s3->peer_tmp then if anything tries to use it then
it will likely fail. This was causing s_client to core dump in the
sslskewith0p test. s_client was trying to print out the connection
parameters that it had negotiated so far. Arguably s_client should not do
that if the connection has failed...but given it is existing functionality
it's easier to fix libssl.
Reviewed-by: NViktor Dukhovni <viktor@openssl.org>

Move the dh_st structure into an internal header file and provide
relevant accessors for the internal fields.
Reviewed-by: NRichard Levitte <levitte@openssl.org>

Suppress CT callbacks with aNULL or PSK ciphersuites that involve
no certificates.  Ditto when the certificate chain is validated via
DANE-TA(2) or DANE-EE(3) TLSA records.  Also skip SCT processing
when the chain is fails verification.

Move and consolidate CT callbacks from libcrypto to libssl.  We
also simplify the interface to SSL_{,CTX_}_enable_ct() which can
specify either a permissive mode that just collects information or
a strict mode that requires at least one valid SCT or else asks to
abort the connection.

Simplified SCT processing and options in s_client(1) which now has
just a simple pair of "-noct" vs. "-ct" options, the latter enables
the permissive callback so that we can complete the handshake and
report all relevant information.  When printing SCTs, print the
validation status if set and not valid.
Signed-off-by: NRob Percival <robpercival@google.com>
Reviewed-by: NEmilia Käsper <emilia@openssl.org>

The original check for != SSL_VERIFY_NONE can give surprising results
when flags SSL_VERIFY_PEER is not set, but other flags are.  Note
that SSL_VERIFY_NONE (0) is not a flag bit, it is rather the absense
of all other flag bits.
Signed-off-by: NRob Percival <robpercival@google.com>
Reviewed-by: NEmilia Käsper <emilia@openssl.org>

Free up parsed X509_NAME structure if the CertificateRequest message
contains excess data.

The security impact is considered insignificant. This is a client side
only leak and a large number of connections to malicious servers would
be needed to have a significant impact.

This was found by libFuzzer.
Reviewed-by: NEmilia Käsper <emilia@openssl.org>
Reviewed-by: NStephen Henson <steve@openssl.org>

This reverts commit 620d540b.
It wasn't reviewed.
Reviewed-by: NRich Salz <rsalz@openssl.org>

Reviewed-by: NRichard Levitte <levitte@openssl.org>
Reviewed-by: NRich Salz <rsalz@openssl.org>

We now send the highest supported version by the client, even if the session
uses an older version.

This fixes 2 problems:
- When you try to reuse a session but the other side doesn't reuse it and
  uses a different protocol version the connection will fail.
- When you're trying to reuse a session with an old version you might be
  stuck trying to reuse the old version while both sides support a newer
  version
Signed-off-by: NKurt Roeckx <kurt@roeckx.be>
Reviewed-by: NViktor Dukhovni <viktor@openssl.org>

GH: #852, MR: #2452

Don't have #error statements in header files, but instead wrap
the contents of that file in #ifndef OPENSSL_NO_xxx
This means it is now always safe to include the header file.
Reviewed-by: NRichard Levitte <levitte@openssl.org>

Reviewed-by: NViktor Dukhovni <viktor@openssl.org>

MR: #1595

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

Disabled by default, but can be enabled by setting the
ct_validation_callback on a SSL or SSL_CTX.
Reviewed-by: NBen Laurie <ben@openssl.org>
Reviewed-by: NRich Salz <rsalz@openssl.org>

Add -DBIO_DEBUG to --strict-warnings.
Remove comments about outdated debugging ifdef guards.
Remove md_rand ifdef guarding an assert; it doesn't seem used.
Remove the conf guards in conf_api since we use OPENSSL_assert, not assert.
For pkcs12 stuff put OPENSSL_ in front of the macro name.
Merge TLS_DEBUG into SSL_DEBUG.
Various things just turned on/off asserts, mainly for checking non-NULL
arguments, which is now removed: camellia, bn_ctx, crypto/modes.
Remove some old debug code, that basically just printed things to stderr:
  DEBUG_PRINT_UNKNOWN_CIPHERSUITES, DEBUG_ZLIB, OPENSSL_RI_DEBUG,
  RL_DEBUG, RSA_DEBUG, SCRYPT_DEBUG.
Remove OPENSSL_SSL_DEBUG_BROKEN_PROTOCOL.
Reviewed-by: NRichard Levitte <levitte@openssl.org>

Remove support for static ECDH ciphersuites. They require ECDH keys
in certificates and don't support forward secrecy.
Reviewed-by: NViktor Dukhovni <viktor@openssl.org>