MFC r326233:

Add to ipfw support for sending an SCTP packet containing an ABORT chunk.
This is similar to the TCP case. where a TCP RST segment can be sent.

There is one limitation: When sending an ABORT in response to an incoming
packet, it should be tested if there is no ABORT chunk in the received
packet. Currently, it is only checked if the first chunk is an ABORT
chunk to avoid parsing the whole packet, which could result in a DOS attack.

Thanks to Timo Voelker for helping me to test this patch.

MFC r327200:

When adding support for sending SCTP packets containing an ABORT chunk
to ipfw in https://svnweb.freebsd.org/changeset/base/326233,
a dependency on the SCTP stack was added to ipfw by accident.

This was noted by Kevel Bowling in https://reviews.freebsd.org/D13594
where also a solution was suggested. This patch is based on Kevin's
suggestion, but implements the required SCTP checksum computation
without any dependency on other SCTP sources.

While there, do some cleanups and improve comments.

Thanks to Kevin Kevin Bowling for reporting the issue and suggesting
a fix.

MFC r326672:

Retire SCTP_WITH_NO_CSUM option.

This option was used in the early days to allow performance measurements
extrapolating the use of SCTP checksum offloading. Since this feature
is now available, get rid of this option.
This also un-breaks the LINT kernel. Thanks to markj@ for making me
aware of the problem.

Revert r330897:

This was intended to be a non-functional change. It wasn't. The commit
message was thus wrong. In addition it broke arm, and merged crypto
related code.

Revert with prejudice.

This revert skips files touched in r316370 since that commit was since
MFCed. This revert also skips files that require $FreeBSD$ property
changes.

Thank you to those who helped me get out of this mess including but not
limited to gonzo, kevans, rgrimes.

Requested by: gjb (re)

Partial merge of the SPDX changes

These changes are incomplete but are making it difficult
to determine what other changes can/should be merged.

No objections from: pfg

MFC r309607:

Whitespace changes.

The tools using to generate the sources has been updated and produces
different whitespaces. Commit this seperately to avoid intermixing
these with real code changes.

Copy head@r302406 to stable/11 as part of the 11.0-RELEASE cycle.
Prune svn:mergeinfo from the new branch, as nothing has been merged
here.

Additional commits post-branch will follow.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Use consistent text at the begining of the files.

MFC after: 3 days

Fix unused parameter warnings.
While there, fix some whitespace issues.

MFC after: 3 months.

1) Typo correction in comments and one spacing change.
2) Mass update to all copyrights.
MFC after: 3 Months

Fix the the SCTP_WITH_NO_CSUM option when used in combination with
interface supporting CRC offload. While at it, make use of the
feature that the loopback interface provides CRC offloading.

MFC after: 4 weeks

The proper fix for the delayed SCTP checksum is to
have the delayed function take an argument as to the offset
to the SCTP header. This allows it to work for V4 and V6.
This of course means changing all callers of the function
to either pass the header len, if they have it, or create
it (ip_hl << 2 or sizeof(ip6_hdr)).
PR: 144529
MFC after: 2 weeks

This commit fixes the issue with alias_sctp.c. No
longer do we require SCTP to be in the kernel for the
lib to be able to handle SCTP. We do this by moving
the CRC32c checksum into libkern/crc32.c and then adjusting
all routines to use the common methods. Note that this
will improve the performance of iSCSI since they were
using the old single 256 bit table lookup versus the
slicing 8 algorithm (which gives a 4x speed up in
CRC32c calculation :-D)

Reviewed by:rwatson, gnn, scottl, paolo
MFC after: 4 week? (assuming we MFC the alias_sctp changes)

Add SCTP NAT support.

Submitted by: CAIA (http://caia.swin.edu.au)

- Cleanup checksum code.
- Prepare for CRC offloading, add MIB counters (RS/MT).
- Bugfix: Disable CRC computation for IPv6 addresses with local scope (MT).
- Bugfix: Handle close() with SO_LINGER correctly when notifications
are generated during the close() call(MT).
- Bugfix: Generate DRY event when sender is dry during subscription.
Only for 1-to-1 style sockets (RS/MT)
- Bugfix: Put vtags for the correct amount of time into time-wait (MT).
- Bugfix: Clear vtag entries correctly on expiration (MT).
- Bugfix: shutdown() indicates ENOTCONN when called for unconnected
1-to-1 style sockets (MT).
- Bugfix: In sctp Auth code (PL).
- Add support for devices that support SCTP csum offload (igb).
- Add missing sctp_associd to mib sysctl xsctp_tcb structure (RS)
Obtained from: With help from Peter Lei and Michael Tuexen

1) Adds the rest of the VIMAGE change macros
2) Adds some __UserSpace__ on some of the common defines that
the user space code needs
3) Fixes a bug when we send up data to a user that failed. We
need to a) trim off the data chunk headers, if present, and
b) make sure the frag bit is communicated properly for the
msgs coming off the stream queues... i.e. we see if some
of the msg has been taken.

Obtained from: jeli contributed the VIMAGE changes on this pass Thanks Julain!

- Copyright change, cisco's silly tool wants it to say:
"Copyright (c) 2001-2007, by Cisco Systems,"
instead of
*Copyright (c) 2001-2007, Cisco Systems,"

- Also fix a few straglers that were still in 2006.

- most all includes (#include <>) migrate to the sctp_os_bsd.h file
- Finally all splxx() are removed
- Count error fixed in mapping array which might
cause a wrong cumack generation.
- Invariants around panic for case D + printf when no invariants.
- one-to-one model race condition fixed by using
a pre-formed connection and then completing the
work so accept won't happen on a non-formed
association.
- Some additional paranoia checks in sctp_output.
- Locks that were missing in the accept code.

Approved by: gnn

Ok, here it is, we finally add SCTP to current. Note that this
work is not just mine, but it is also the works of Peter Lei
and Michael Tuexen. They both are my two key other developers
working on the project.. and they need ata-boy's too:
****
peterlei@cisco.com
tuexen@fh-muenster.de
****
I did do a make sysent which updated the
syscall's and sysproto.. I hope that is correct... without
it you don't build since we have new syscalls for SCTP :-0

So go out and look at the NOTES, add
option SCTP (make sure inet and inet6 are present too)
and play with SCTP.

I will see about comitting some test tools I have after I
figure out where I should place them. I also have a
lib (libsctp.a) that adds some of the missing socketapi
functions that I need to put into lib's.. I will talk
to George about this :-)

There may still be some 64 bit issues in here, none of
us have a 64 bit processor to test with yet.. Michael
may have a MAC but thats another beast too..

If you have a mac and want to use SCTP contact Michael
he maintains a web site with a loadable module with
this code :-)

Reviewed by: gnn
Approved by: gnn