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: Andy 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: Andy Polyakov <appro@openssl.org>

Add the ability to peek at a message from the DTLS read BIO. This is needed
for the DTLSv1_listen rewrite.

Reviewed-by: Andy Polyakov <appro@openssl.org>

The openssl rehash command is not available on some platforms including
Windows. This change skips the associated tests if rehash is not available.

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

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

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

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

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

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

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

Get rid of the third field that is no longer needed.

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

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

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

Fix comment, add another overflow check, tidy style

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

BUF_strndup was calling strlen through BUF_strlcpy, and ended up reading
past the input if the input was not a C string.

Make it explicitly part of BUF_strndup's contract to never read more
than |siz| input bytes. This augments the standard strndup contract to
be safer.

The commit also adds a check for siz overflow and some brief documentation
for BUF_strndup().

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

For all release branches.  It adds travis build support. If you don't
have a config file it uses the default (because we enabled travis for the
project), which uses ruby/rake/rakefiles, and you get confusing "build
still failing" messages.

Reviewed-by: Andy Polyakov <appro@openssl.org>

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

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

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

Move various functions tagged onto t_x509.c to more appropriate places.

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

Reviewed-by: Rich Salz <rsalz@openssl.org>
Reviewed-by: Emilia Käsper <emilia@openssl.org>

Reviewed-by: Rich Salz <rsalz@openssl.org>
Reviewed-by: Emilia Käsper <emilia@openssl.org>

Reviewed-by: Rich Salz <rsalz@openssl.org>
Reviewed-by: Emilia Käsper <emilia@openssl.org>

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

If we use BIO_new_file(), on Windows it'll jump through hoops to work
around their unusual charset/Unicode handling. it'll convert a UTF-8
filename to UCS-16LE and attempt to use _wfopen().

If you use BIO_read_filename(), it doesn't do this. Shouldn't it be
consistent?

It would certainly be nice if SSL_use_certificate_chain_file() worked.

Also made BIO_C_SET_FILENAME work (rsalz)

Signed-off-by: Rich Salz <rsalz@akamai.com>
Reviewed-by: Andy Polyakov <appro@openssl.org>