When tearing down a TCP connection, try injecting a RST segment
by pretending to peer has received the last packet as an out of
the blue packet.

This avoids conflics with definitions on Solaris 10.4.

This adds support for SCTP/UDP and TCP/UDP including ICMP
support.

Sponsored by:	Netflix, Inc.

When outbound HEARTBEAT chunks are observed, inject the appropriate
HEARTBEAT-ACK chunk when scripted.
While there, plug a memory leak and rename a variable for consistency.
This fixes https://github.com/nplab/packetdrill/issues/11

Current limitations:
* Chunk parameters are not yet supported.
* Error causes are not yet supported.
* Chunks can't be bundled with COOKIE-ECHO chunks.
* Chunk flags are not supported.
* Chunk lengths are not supported.
* Gap reports and duplicate TSNs are not supported for SACK chunks.
* SCTP related ICMP messages are not supported.
This version is only tested in a limited way, only on FreeBSD and
only in local mode.

This commit adds support for parsing SCTP packets and converting them
to strings. Currently only chunks, parameters and error causes specified
in RFC 4960 are supported. Support for other RFCs will be added in the
future.
Tested on FreeBSD (amd64 and arm) and Linux.

Signed-off-by: Michael Tuexen <tuexen@fh-muenster.de>

This commit adds support for UDPLite as specified in RFC 3828
and the corresponding socket options.
It is tested on FreeBSD 10.1 and Linux, the platforms supporting
UDPLite.

Signed-off-by: Michael Tuexen <tuexen@fh-muenster.de>

Initial commit for the packetdrill network stack testing tool:

  https://code.google.com/p/packetdrill/



Signed-off-by: Neal Cardwell <ncardwell@google.com>