The function ssl3_get_message gets a whole message from the underlying bio
and returns it to the state machine code. The new state machine code will
split this into two discrete steps: get the message header and get the
message body. This commit splits the existing function into these two
sub steps to facilitate the state machine implementation.
Reviewed-by: NTim Hudson <tjh@openssl.org>
Reviewed-by: NRichard Levitte <levitte@openssl.org>

RT#4081
Reviewed-by: NRich Salz <rsalz@openssl.org>
Reviewed-by: NRichard Levitte <levitte@openssl.org>

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

Change the sanity check in PACKET_buf_init to check for excessive length
buffers, which should catch the interesting cases where len has been cast
from a negative value whilst avoiding any undefined behaviour.

RT#4094
Reviewed-by: NRichard Levitte <levitte@openssl.org>

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

False positive: gcc (4.8) can't figure out the SSL_IS_DTLS logic.
Reviewed-by: NRichard Levitte <levitte@openssl.org>

PR#4035
Reviewed-by: NMatt Caswell <matt@openssl.org>

Note that this commit constifies a user callback parameter and therefore
will break compilation for applications using this callback. But unless
they are abusing write access to the buffer, the fix is trivial.
Reviewed-by: NAndy Polyakov <appro@openssl.org>

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

The function ssl_check_for_safari fingerprints the incoming extensions
to see whether it is one of the broken versions of safari. However it was
failing to reset the PACKET back to the same position it started in, hence
causing some extensions to be skipped incorrectly.
Reviewed-by: NEmilia Käsper <emilia@openssl.org>

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

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

RT#4069
Reviewed-by: NEmilia Käsper <emilia@openssl.org>
Reviewed-by: NMatt Caswell <matt@openssl.org>

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

The user callback takes a non-const pointer, so don't pass PACKET data
to it directly; rather, grab a local copy.
Reviewed-by: NMatt Caswell <matt@openssl.org>

Fix alerts.
Reviewed-by: NMatt Caswell <matt@openssl.org>

Move all packet parsing to the beginning of the method. This limits the
SSLv2 compatibility soup to the parsing, and makes the rest of the
processing uniform.

This is also needed for simpler EMS support: EMS servers need to do an
early scan for EMS to make resumption decisions. This'll be easier when
the entire ClientHello is parsed in the beginning.

As a side effect,
1) PACKETize ssl_get_prev_session and tls1_process_ticket; and
2) Delete dead code for SSL_OP_NETSCAPE_REUSE_CIPHER_CHANGE_BUG.
Reviewed-by: NMatt Caswell <matt@openssl.org>

Reviewed-by: NBen Laurie <ben@openssl.org>

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

This patch updates the "DEFAULT" cipherstring to be
"ALL:!COMPLEMENTOFDEFAULT:!eNULL". COMPLEMENTOFDEFAULT is now defined
internally by a flag on each ciphersuite indicating whether it should be
excluded from DEFAULT or not. This gives us control at an individual
ciphersuite level as to exactly what is in DEFAULT and what is not.

Finally all DES, RC4 and RC2 ciphersuites are added to COMPLEMENTOFDEFAULT
and hence removed from DEFAULT.
Reviewed-by: NTim Hudson <tjh@openssl.org>

Much related/similar work also done by
Ivan Nestlerode <ivan.nestlerode@sonos.com>

   +Replace FILE BIO's with dummy ops that fail.
   +Include <stdio.h> for sscanf() even with no-stdio (since the declaration
    is there). We rely on sscanf() to parse the OPENSSL_ia32cap environment
    variable, since it can be larger than a 'long'. And we don't rely on the
    availability of strtoull().
   +Remove OPENSSL_stderr(); not used.
   +Make OPENSSL_showfatal() do nothing (currently without stdio there's
    nothing we can do).
   +Remove file-based functionality from ssl/. The function
    prototypes were already gone, but not the functions themselves.
   +Remove unviable conf functionality via SYS_UEFI
   +Add fallback definition of BUFSIZ.
   +Remove functions taking FILE * from header files.
   +Add missing DECLARE_PEM_write_fp_const
   +Disable X509_LOOKUP_hash_dir(). X509_LOOKUP_file() was already compiled out,
    so remove its prototype.
   +Use OPENSSL_showfatal() in CRYPTO_destroy_dynlockid().
   +Eliminate SRP_VBASE_init() and supporting functions. Users will need to
    build the verifier manually instead.
   +Eliminate compiler warning for unused do_pk8pkey_fp().
   +Disable TEST_ENG_OPENSSL_PKEY.
   +Disable GOST engine as is uses [f]printf all over the place.
   +Eliminate compiler warning for unused send_fp_chars().
Signed-off-by: NRich Salz <rsalz@akamai.com>
Reviewed-by: NTim Hudson <tjh@openssl.org>

Reviewed-by: NTim Hudson <tjh@openssl.org>

RFC 5077 section 3.3 says:
If the server determines that it does not want to include a
ticket after it has included the SessionTicket extension in the
ServerHello, then it sends a zero-length ticket in the
NewSessionTicket handshake message.

Previously the client would fail upon attempting to allocate a
zero-length buffer. Now, we have the client ignore the empty ticket and
keep the existing session.
Reviewed-by: NMatt Caswell <matt@openssl.org>

Previously you could only set both the default path and file locations
together. This adds the ability to set one without the other.
Reviewed-by: NAndy Polyakov <appro@openssl.org>

Add a sanity check that the cookie_len returned by app_gen_cookie_cb is
valid.
Reviewed-by: NAndy Polyakov <appro@openssl.org>

The old implementation of DTLSv1_listen which has now been replaced still
had a few vestiges scattered throughout the code. This commit removes them.
Reviewed-by: NAndy Polyakov <appro@openssl.org>

The existing implementation of DTLSv1_listen() is fundamentally flawed. This
function is used in DTLS solutions to listen for new incoming connections
from DTLS clients. A client will send an initial ClientHello. The server
will respond with a HelloVerifyRequest containing a unique cookie. The
client the responds with a second ClientHello - which this time contains the
cookie.

Once the cookie has been verified then DTLSv1_listen() returns to user code,
which is typically expected to continue the handshake with a call to (for
example) SSL_accept().

Whilst listening for incoming ClientHellos, the underlying BIO is usually in
an unconnected state. Therefore ClientHellos can come in from *any* peer.
The arrival of the first ClientHello without the cookie, and the second one
with it, could be interspersed with other intervening messages from
different clients.

The whole purpose of this mechanism is as a defence against DoS attacks. The
idea is to avoid allocating state on the server until the client has
verified that it is capable of receiving messages at the address it claims
to come from. However the existing DTLSv1_listen() implementation completely
fails to do this. It attempts to super-impose itself on the standard state
machine and reuses all of this code. However the standard state machine
expects to operate in a stateful manner with a single client, and this can
cause various problems.

A second more minor issue is that the return codes from this function are
quite confused, with no distinction made between fatal and non-fatal errors.
Most user code treats all errors as non-fatal, and simply retries the call
to DTLSv1_listen().

This commit completely rewrites the implementation of DTLSv1_listen() and
provides a stand alone implementation that does not rely on the existing
state machine. It also provides more consistent return codes.
Reviewed-by: NAndy Polyakov <appro@openssl.org>

Get rid of the third field that is no longer needed.
Reviewed-by: NRich Salz <rsalz@openssl.org>

Since SSLv3, a CipherSuite is always 2 bytes. The only place where we
need 3-byte ciphers is SSLv2-compatible ClientHello processing.

So, remove the ssl_put_cipher_by_char indirection.
Reviewed-by: NRich Salz <rsalz@openssl.org>

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

It's unused, and the same functionality can be achieved with saving a
copy of the struct.
Reviewed-by: NRich Salz <rsalz@openssl.org>

The bookmark API results in a lot of boilerplate error checking that can
be much more easily achieved with a simple struct copy. It also lays the
path for removing the third PACKET field.
Reviewed-by: NRich Salz <rsalz@openssl.org>

Make sure it's valid very early.
Signed-off-by: NRich Salz <rsalz@openssl.org>
Reviewed-by: NRichard Levitte <levitte@openssl.org>

Simplify encrypted premaster secret reading by using new methods in the
PACKET API.

Don't overwrite the packet buffer. RSA decrypt accepts truncated
ciphertext with leading zeroes omitted, so it's even possible that by
crafting a valid ciphertext with several leading zeroes, this could
cause a few bytes out-of-bounds write. The write is harmless because of
the size of the underlying message buffer, but nevertheless we shouldn't
write into the packet.
Reviewed-by: NMatt Caswell <matt@openssl.org>

Reviewed-by: NRich Salz <rsalz@openssl.org>
MR #1128

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

For server use a PSK identity hint value in the CERT structure which
is inherited when SSL_new is called and which allows applications to
set hints on a per-SSL basis. The previous version of
SSL_use_psk_identity_hint tried (wrongly) to use the SSL_SESSION structure.

PR#4039
Reviewed-by: NMatt Caswell <matt@openssl.org>

-Wincompatible-pointer-types-discards-qualifiers (the latter did not require
any code changes).
Reviewed-by: NRich Salz <rsalz@openssl.org>

Reviewed-by: NDr Stephen Henson <steve@openssl.org>

Use each once in s3_srvr.c to show how they work.

Also fix a bug introduced in c3fc7eea
and made apparent by this change:
ssl3_get_next_proto wasn't updating next_proto_negotiated_len
Reviewed-by: NMatt Caswell <matt@openssl.org>