sctp: improve heartbeat timer computation
PR: 278666
Reviewed by: Albin Hellqvist
MFC after: 3 days
Pull Request: https://reviews.freebsd.org/D45107

sctp: store cookie secret change time as time_t
Reported by: Coverity Scan
CID: 1492349
CID: 1493281
MFC after: 3 days

sockets: garbage collect SS_ISCONFIRMING

Fixes: 8df32b19dee92b5eaa4b488ae78dca6accfcb38e

sctp: don't call sctp_ulp_notify() recursively

This does not work with the new locking scheme.

MFC after: 3 days

sctp: cleanup locking for notifications

All notifications are now queued via sctp_ulp_notify(). Do
the locking of the inp read lock there and validate this in all
functions being used.
This is one step in avoiding race conditions when closing the
read end of an SCTP socket.

MFC after: 3 days

sctp: make sure all SCTP RESET notifications use sctp_ulp_notify()

While there, improve consistency of the notification related code.
No functional change intended.

MFC after: 3 days

sctp: cleanup SCTP AUTH related notification

This makes consistent use of the parameters and ensures that
all SCTP AUTH related notifications are using sctp_ulp_notify().

No functional change intended.

MFC after: 3 days

sctp: cleanup

In particular, don't use a socket level flag, use the inp level one.
After adding appropriate locking, this will close a race condition.

MFC after: 1 week

sctp: cleanup cdefs.h include

sys: Remove $FreeBSD$: one-line .c pattern

Remove /^[\s*]*__FBSDID\("\$FreeBSD\$"\);?\s*\n/

sctp: cleanup

Do not put a variable in the stcb for passing it to a function.
Just use a parameter of the function. No functional change intended.

MFC after: 1 week

sctp: add an assert

This enforces a condition mentioned in a comment.

MFC after: 1 week

sctp: improve consistency

MFC after: 1 week

sctp: remove redundant check

This is already checked by the caller.

MFC after: 1 week

sctp: keep sb_acc and sb_ccc in sync

PR: 260116
MFC after: 1 week

sctp: improve consistency

This is simplifying a patch to address PR 260116.

PR: 260116
MFC after: 1 week

sctp: update zero checksum support

Implement support for the error detection method identifier.
MFC after: 2 weeks

sctp: initial implementation of draft-tuexen-tsvwg-sctp-zero-checksum

sctp: improve delivery of stream reset notifications

Two functions are not called via sctp_ulp_notify() and therefore
need additional checks when being called.

Reported by: syzbot+eb888d3a5a6c54413de5@syzkaller.appspotmail.com
MFC after: 3 days

netinet*: remove PRC_ constants and streamline ICMP processing

In the original design of the network stack from the protocol control
input method pr_ctlinput was used notify the protocols about two very
different kinds of events: internal system events and receival of an
ICMP messages from outside. These events were coded with PRC_ codes.
Today these methods are removed from the protosw(9) and are isolated
to IPv4 and IPv6 stacks and are called only from icmp*_input(). The
PRC_ codes now just create a shim layer between ICMP codes and errors
or actions taken by protocols.

- Change ipproto_ctlinput_t to pass just pointer to ICMP header. This
allows protocols to not deduct it from the internal IP header.
- Change ip6proto_ctlinput_t to pass just struct ip6ctlparam pointer.
It has all the information needed to the protocols. In the structure,
change ip6c_finaldst fields to sockaddr_in6. The reason is that
icmp6_input() already has this address wrapped in sockaddr, and the
protocols want this address as sockaddr.
- For UDP tunneling control input, as well as for IPSEC control input,
change the prototypes to accept a transparent union of either ICMP
header pointer or struct ip6ctlparam pointer.
- In icmp_input() and icmp6_input() do only validation of ICMP header and
count bad packets. The translation of ICMP codes to errors/actions is
done by protocols.
- Provide icmp_errmap() and icmp6_errmap() as substitute to inetctlerrmap,
inet6ctlerrmap arrays.
- In protocol ctlinput methods either trust what icmp_errmap() recommend,
or do our own logic based on the ICMP header.

Differential revision: https://reviews.freebsd.org/D36731

sctp: improve handling of sctp inpcb flags

Use an atomic operation when the inp is not write locked.

Reported by: syzbot+bf27083e9a3f8fde8b4d@syzkaller.appspotmail.com
MFC after: 3 days

sctp: more sb_cc related cleanups

No functional change intended. It allows a simpler patch for PR 260116.

MFC after: 3 days

sctp: use sb_avail() when accessing sb_acc for reading

This is a cleanup to simplify a patch for PR 260116.

PR: 260116
MFC after: 3 days

sctp: cleanup, no functional change intended

MFC after: 3 days

sctp: improve path verification

When sending path confirmation heartbeats, do not take HB.interval
into account when the path is still reachable.

Thanks to Alexander Funke for finding the issue and suggesting a fix.

MFC after: 3 days

sctp: improve consistency

No functional change intended.

MFC after: 3 days

sockets: use socket buffer mutexes in struct socket directly

Since c67f3b8b78e the sockbuf mutexes belong to the containing socket,
and socket buffers just point to it. In 74a68313b50 macros that access
this mutex directly were added. Go over the core socket code and
eliminate code that reaches the mutex by dereferencing the sockbuf
compatibility pointer.

This change requires a KPI change, as some functions were given the
sockbuf pointer only without any hint if it is a receive or send buffer.

This change doesn't cover the whole kernel, many protocols still use
compatibility pointers internally. However, it allows operation of a
protocol that doesn't use them.

Reviewed by: markj
Differential revision: https://reviews.freebsd.org/D35152

sctp: improve locking

While there, do some cleanup.

Reported by: syzbot+f475e054c454310bc26d@syzkaller.appspotmail.com
MFC after: 3 day

sctp: cleanup

MFC after: 3 days

sctp: improve stopping of timers

Reported by: syzbot+c9c70062320aaad19de7@syzkaller.appspotmail.com
MFC after: 3 days

sctp: cleanup

MFC after: 3 days

sctp: don't wakeup 1-to-1 listening sockets for data or notifications

Reported by: syzbot+ec9279d306a4ff0215f8@syzkaller.appspotmail.com
Reported by: syzbot+31d54f6d486333493dd4@syzkaller.appspotmail.com
MFC after: 3 days

udp: allow udp_tun_func_t() to indicate it did not eat the packet

Allow udp tunnel functions to indicate they have not taken ownership of
the packet, and that normal UDP processing should continue.

This is especially useful for scenarios where the kernel has taken
ownership of a socket that was originally created by userspace. It
allows the tunnel function to pass through certain packets for userspace
processing.

The primary user of this is if_ovpn, when it receives messages from
unknown peers (which might be a new client).

Reviewed by: tuexen
Sponsored by: Rubicon Communications, LLC ("Netgate")
Differential Revision: https://reviews.freebsd.org/D34883

sctp: fix typos

Thanks to David Sanders for fixing the typos in the userland stack.

MFC after: 3 days

sctp: get rid of stcb send lock

Just use the stcb lock instead to simplify locking.

Reported by: syzbot+d00b202063150f85b110@syzkaller.appspotmail.com
Reported by: syzbot+87f268a0a6d2d6383306@syzkaller.appspotmail.com
MFC after: 3 days

sctp: retire sctp_mtu_size_reset()

Thanks to Timo Voelker for making me aware that sctp_mtu_size_reset()
is very similar to sctp_pathmtu_adjustment().

MFC after: 3 days

sctp: cleanup the SCTP_MAXSEG socket option.

This patch makes the handling of the SCTP_MAXSEG socket option
compliant with RFC 6458 (SCTP socket API) and fixes an issue
found by syzkaller.

Reported by: syzbot+a2791b89ab99121e3333@syzkaller.appspotmail.com
MFC after: 3 days

sctp: cleanup, on functional change intended.

MFC after: 3 days

sctp: improve consistency, no functional change intended

sctp: add some asserts, no functional changes intended

This might help in narrowing down
https://syzkaller.appspot.com/bug?id=fbd79abaec55f5aede63937182f4247006ea883b

netinet: Fix a common typo in source code comments

- s/writting/writing/

MFC after: 3 days

sctp: Simplify stream scheduler usage

Callers are getting the stcb send lock, so just KASSERT that.
No need to signal this when calling stream scheduler functions.
No functional change intended.

MFC after: 1 week

sctp: improve consistency when calling stream scheduler

Hold always the stcb send lock when calling sctp_ss_init() and
sctp_ss_remove_from_stream().

MFC after: 1 week

sctp: Allow blocking on I/O locks even with non-blocking sockets

There are two flags to request a non-blocking receive on a socket:
MSG_NBIO and MSG_DONTWAIT. They are handled a bit differently in that
soreceive_generic() and soreceive_stream() will block on the socket I/O
lock when MSG_NBIO is set, but not if MSG_DONTWAIT is set. In general,
MSG_NBIO seems to mean, "don't block if there is no data to receive" and
MSG_DONTWAIT means "don't go to sleep for any reason".

SCTP's soreceive implementation did not allow blocking on the I/O lock
if either flag is set, but this violates an assumption in
aio_process_sb(), which specifies MSG_NBIO but nonetheless
expects to make progress if data is available to read. Change
sctp_sorecvmsg() to block on the I/O lock only if MSG_DONTWAIT
is not set.

Reported by: syzbot+c7d22dbbb9aef509421d@syzkaller.appspotmail.com
Reviewed by: tuexen
MFC after: 1 week
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D31915

sctp: minor cleanups, no functional change intended

socket: Rename sb(un)lock() and interlock with listen(2)

In preparation for moving sockbuf locks into the containing socket,
provide alternative macros for the sockbuf I/O locks:
SOCK_IO_SEND_(UN)LOCK() and SOCK_IO_RECV_(UN)LOCK(). These operate on a
socket rather than a socket buffer. Note that these locks are used only
to prevent concurrent readers and writters from interleaving I/O.

When locking for I/O, return an error if the socket is a listening
socket. Currently the check is racy since the sockbuf sx locks are
destroyed during the transition to a listening socket, but that will no
longer be true after some follow-up changes.

Modify a few places to check for errors from
sblock()/SOCK_IO_(SEND|RECV)_LOCK() where they were not before. In
particular, add checks to sendfile() and sorflush().

Reviewed by: tuexen, gallatin
MFC after: 1 month
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D31657

sctp: improve input validation of mapped addresses in sctp_connectx()
MFC after: 3 days

sctp: Fix errno in case of association setup failures

Do not report always ETIMEDOUT, but only when appropriate. In
other cases report ECONNABORTED.

MFC after: 3 days

sctp: provide consistent stream information in case of early errors

While there, make sure the function is called correctly.

MFC after: 3 days

sctp: provide sac_error also for ABORT chunk being sent

Thanks to Florent Castelli for bringing this issue up for the
userland stack and providing an initial patch.

MFC: 3 days

sctp: initialize sequence numbers for ECN correctly

MFC after: 3 days
Reported by: Junseok Yang (for the userland stack)

Consistently use the SOCKBUF_MTX() and SOCK_MTX() macros

This makes it easier to change the socket locking protocols. No
functional change intended.

MFC after: 1 week
Sponsored by: The FreeBSD Foundation

sctp: update the vtag for INIT and INIT-ACK chunks

This is needed in case of responding with an ABORT to an INIT-ACK.

sctp: fix handling of RTO.initial of 1 ms

MFC after: 3 days
Reported by: syzbot+5eb0e009147050056ce9@syzkaller.appspotmail.com

sctp: avoid integer overflow when starting the HB timer

MFC after: 3 days
Reported by: syzbot+14b9d7c3c64208fae62f@syzkaller.appspotmail.com

sctp: small cleanup, no functional change intended.

MFC after: 3 days

sctp: improve consistency

No functional change intended.

MFC: 1 week

Remove dead stores reported by clang static code analysis

MFC after: 3 days

net: clean up empty lines in .c and .h files

Improve the handling of concurrent send() calls for SCTP sockets,
especially when having the explicit EOR mode enabled.

Reported by: Megan2013678@protonmail.com
Reported by: syzbot+bc02585076c3cc977f9b@syzkaller.appspotmail.com
MFC after: 3 days

Enter epoch earlier. This is needed because we are exiting it also
in error cases.

MFC after: 1 week

Add reference counts for inp/stcb/net when timers are running.
This avoids a use-after-free reported for the userland stack.
Thanks to Taylor Brandstetter for suggesting a patch for
the userland stack.

MFC after: 1 week

Improve the locking of address lists by adding some asserts and
rearranging the addition of address such that the lock is not
given up during checking and adding.

MFC after: 1 week

Fix a bug introduced in https://svnweb.freebsd.org/changeset/base/362173

Reported by: syzbot+f3a6fccfa6ae9d3ded29@syzkaller.appspotmail.com
MFC after: 1 week

Fix the build for an INET6 only configuration.

The fix from the last commit is actually needed twice...

MFC after: 1 week

Set a variable also in the case of an INET6 only kernel

MFC after: 1 week

Cleanup the adding and deleting of addresses via sctp_bindx().

There is no need to use the association identifier, so remove it.
While there, cleanup the code a bit.

MFC after: 1 week

Remove last argument of sctp_addr_mgmt_ep_sa(), since it is not used.

MFC after: 1 week

Allow the self reference to be NULL in case the timer was stopped.

Submitted by: Timo Voelker
MFC after: 1 week

Cleanups, no functional change.

MFC after: 1 week

Non-functional changes due to upstream cleanup.

MFC after: 1 week

Whitespace cleanups and removal of a stale comment.

MFC after: 1 week

Retire SCTP_SO_LOCK_TESTING.

This was intended to test the locking used in the MacOS X kernel on a
FreeBSD system, to make use of WITNESS and other debugging infrastructure.
This hasn't been used for ages, to take it out to reduce the #ifdef
complexity.

MFC after: 1 week

Remove redundant assignment.

MFC after: 3 days

Fix logical condition by looking at usecs.

This issue was found by cpp-check running on the userland stack.

MFC after: 3 days

Whitespace change.

MFC after: 3 days

Ensure that the SCTP iterator runs with an stcb and inp, which belong to
each other.

Reported by: syzbot+82d39d14f2f765e38db0@syzkaller.appspotmail.com
MFC after: 3 days

Ensure that we have a path when starting the T3 RXT timer.

Reported by: syzbot+f2321629047f89486fa3@syzkaller.appspotmail.com
MFC after: 3 days

Do more argument validation under INVARIANTS when starting/stopping
an SCTP timer.

MFC after: 1 week

Handle integer overflows correctly when converting msecs and secs to
ticks and vice versa.
These issues were caught by recently added panic() calls on INVARIANTS
systems.

Reported by: syzbot+b44787b4be7096cd1590@syzkaller.appspotmail.com
Reported by: syzbot+35f82d22805c1e899685@syzkaller.appspotmail.com
MFC after: 1 week

Remove an optimization, which was incorrect a couple of times and
therefore doesn't seem worth to be there.
In this case COOKIE where not retransmitted anymore, when the
socket was already closed.

MFC after: 1 week

Improve consistency in debug output.

MFC after: 1 week

Use consistent debug output.

MFC after: 1 week

Don't restore the vnet too early in error cases.

MFC after: 1 week

Only call panic when building with INVARIANTS.

MFC after: 1 week

Another cleanup of the timer code. Also be more pedantic about the
parameters of the timer start and stop routines. Several inconsistencies
have been fixed in earlier commits. Now they will be catched when running
an INVARIANTS system.

MFC after: 1 week

More timer cleanups, no functional change.

MFC after: 1 week

Consistently provide arguments for timer start and stop routines.
This is another step in cleaning up timer handling.
MFC after: 1 week

Cleanup the stream reset and asconf timer.

MFC after: 1 week

The MTU candidates MUST be a multiple of 4, so make them so.

MFC after: 1 week

Handle the timers in a consistent sequence according to the definition
of the timer type.
Just a cleanup, no functional change intended.

MFC after: 1 week

Epochify SCTP.

Revert https://svnweb.freebsd.org/changeset/base/357761

This was suggested by cem@

Don't start an SCTP timer using a net, which has been removed.

Submitted by: Taylor Brandstetter
MFC after: 1 week

Use an int instead of a bool variable, since bool is not supported
on all platforms the stack is running on in userland.

Cleanup timer handling.

Submitted by: Taylor Brandstetter
MFC after: 1 week

Remove unused timer.

Submitted by: Taylor Brandstetter

Ensure that we don't miss a trigger for kicking off the SCTP iterator.

Reported by: nwhitehorn@
MFC after: 1 week

Separate out SCTP related dtrace code.
This is based on work done by markj@.

Discussed with: markj@
MFC after: 3 days

Cleanup the RTO calculation and perform some consistency checks
before computing the RTO.
This should fix an overflow issue reported by Felix Weinrank in
https://github.com/sctplab/usrsctp/issues/375
for the userland stack and found by running a fuzz tester.

MFC after: 3 days

Fix build issues for the userland stack on Raspbian.

Don't free read control entries, which are still on the stream queue when
adding them the the read queue fails

MFC after: 1 week

Improve input validation for the IPPROTO_SCTP level socket options
SCTP_CONNECT_X and SCTP_CONNECT_X_DELAYED.

Some issues where found by running syzkaller.

MFC after: 3 days

Fix an SCTP related locking issue. Don't report that the TCB_SEND_LOCK
is owned, when it is not.

This issue was found by running syzkaller.
MFC after: 1 week

Fix build issue for the userland stack.
Joint work with rrs@.

MFC after: 1 week

Fix a signed/unsigned bug when receiving SCTP messages.
This is joint work with rrs@.

Reported by: syzbot+6b8a4bc8cc828e9d9790@syzkaller.appspotmail.com
MFC after: 1 week

Fix a locking issue when reporing outbount messages.

MFC after: 3 days

Whitespace changes and fixing a typo. No functional change.

Approved by: re (kib@)
MFC after: 1 week

Add support for send, receive and state-change DTrace providers for
SCTP. They are based on what is specified in the Solaris DTrace manual
for Solaris 11.4.

Reviewed by: 0mp, dteske, markj
Relnotes: yes
Differential Revision: https://reviews.freebsd.org/D16839

Whitespace change.

Refactor the SHUTDOWN_PENDING state handling.

This is not a functional change but a preperation for the upcoming
DTrace support. It is necessary to change the state in one
logical operation, even if it involves clearing the sub state
SHUTDOWN_PENDING.

MFC after: 1 month

Use the stacb instead of the asoc in state macros.

This is not a functional change. Just a preparation for upcoming
dtrace state change provider support.

Use consistently the macors to modify the assoc state.

No functional change.

Whitespace changes due to changes in ident.

Revert https://svnweb.freebsd.org/changeset/base/336503
since I also ran the export script with different parameters.

Whitespace changes due to change if ident.

Use correct mask.
Introduced in https://svnweb.freebsd.org/changeset/base/333603.
Thanks to Irene Ruengler for testing and reporting the issue.

MFC after: 1 week
X-MFC-with: 333603

Only fillin data srucuture when actually stored.

netinet silence warnings

Ensure that the MTU's used are multiple of 4.

The length of SCTP packets is always a multiple of 4. Therefore,
ensure that the MTUs used are also a multiple of 4.

Thanks to Irene Ruengeler for providing an earlier version of this
patch.

MFC after: 1 week

Fix two typos reported by N. J. Mann, which were introduced in
https://svnweb.freebsd.org/changeset/base/333382 by me.

MFC after: 3 days

When reporting ERROR or ABORT chunks, don't use more data
that is guaranteed to be contigous.
Thanks to Felix Weinrank for finding and reporting this bug
by fuzzing the usrsctp stack.

MFC after: 3 days

Don't provide a (meaningless) cmsg when proving a notification
in a recvmsg() call.

MFC after: 1 week

Unbreak compilation when using SCTP_DETAILED_STR_STATS option.

MFC after: 1 week

sys: further adoption of SPDX licensing ID tags.

Mainly focus on files that use BSD 3-Clause license.

The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.

Special thanks to Wind River for providing access to "The Duke of
Highlander" tool: an older (2014) run over FreeBSD tree was useful as a
starting point.

Allow the setting of the MTU for future paths using an SCTP socket option.
This functionality was missing.

MFC after: 1 week

Code cleanup, not functional change.

This avoids taking a pointer of a packed structure which allows simpler
compilation of the userland stack.

MFC after: 1 week

Protect the address workqueue timer by a mutex.

MFC after: 1 week

Remove code not used on any platform currently supported.

MFC after: 1 week

Use memset/memcpy instead of bzero/bcopy.

Just use one variant instead of both. Use the memset/memcpy
ones since they cause less problems in crossplatform deployment.

MFC after: 1 week

Fix the accounting and add code to detect errors in accounting.
Joint work with rrs@
MFC after: 1 week

Improve compilation on platforms different from FreeBSD.

This code was missing socket unlock and socket buffer lock, but it
worked since right now these two locks are the same.

Allow SCTP to use the hostcache.

This patch allows the MTU stored in the hostcache to be used as an
initial value for SCTP paths. When an ICMP PTB message is received,
store the MTU in the hostcache.

MFC after: 1 week

Use consistently uint32_t for mtu values.

This does not change functionality, but this cleanup is need for further
improvements of ICMP handling.

MFC after: 1 week

Whitespace changes.

The toolchain for processing the sources has been updated. No functional
change.

MFC after: 3 days

Ensure that the reported ppid and tsn are taken from the first fragment.

This fixes a bug where the wrong ppid was reported, if
* I-DATA was used on the first fragement was not received first
* DATA was used and different ppids where used.

Thanks to Julian Cordes for making me aware of the issue.

MFC after: 1 week

Cleanup the names of SSN, SID, TSN, FSN, PPID and MID.

This made a couple of bugs visible in handling SSN wrap-arounds
when using DATA chunks. Now bulk transfer seems to work fine...
This fixes the issue reported in
https://github.com/sctplab/usrsctp/issues/111

MFC after: 1 week

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.

MFC after: 3 days

When aborting an association, send the ABORT before notifying the upper
layer. For the kernel this doesn't matter, for the userland stack, it does.
While there, silence a clang warning when compiling it in userland.

Unbreak sctp_connectx().

MFC after: 3 days

Ensure that sctp_it_ctl.cur_it does not point to a free object (during
a small time window).
Thanks to Byron Campen for reporting the issue and
suggesting a fix.

MFC after: 3 days

Fix a locking issue found by stress testing with tsctp.
The inp read lock neeeds to be held when considering control->do_not_ref_stcb.
MFC after: 3 days

Remove stream queue entry consistently from wheel.
While there, improve the handling of drain.

MFC after: 3 days

Don't modify a structure without holding a reference count on it.

MFC after: 3 days

Fix various bugs in relation to the I-DATA chunk support

This is joint work with rrs.

MFC after: 3 days

This patch fixes two bugs related to the SCTP message recovery
for messages which have been put on the send queue:
* Do not report any DATA or I-DATA chunk padding.
* Correctly deal with the I-DATA chunk header instead of the DATA
chunk header when the I-DATA extension is used.

Approved by: re (kib)
MFC after: 1 week

Fix a bug in the handling of non-blocking SCTP 1-to-1 sockets. When using
this code in the userland stack, it could result in a loop. This happened on iOS.
However, I was not able to reproduce this when using the code in the kernel.
Thanks to Eugen-Andrei Gavriloaie for reporting the issue and proving detailed
information to find the root of the problem.

Approved by: re (gjb)
MFC after: 1 week

Don't consider the socket when processing an incoming ICMP/ICMP6 packet,
which was triggered by an SCTP packet. Whether a socket exists, is just
not relevant.

Approved by: re (kib)
MFC after: 1 week

Use a separate MID counter for ordered und unordered messages for each
outgoing stream.

Thanks to Jens Hoelscher for reporting the issue.

MFC after: 1 week

Fix a bug introduced by the implementation of I-DATA support.
There was the requirement that two structures are in sync,
which is not valid anymore. Therefore don't rely on this
in the code anymore.
Thanks to Radek Malcic for reporting the issue. He found this
when using the userland stack.

MFC after: 1 week

netinet/sctp*: minor spelling fixes in comments.

No functional change.

Reviewed by: tuexen

Add the UDP encaps port as a parameter to sctp_add_remote_addr().

This is currently only a code change without any functional
change. But this allows to set the remote encapsulation port
in a more detailed way, which will be provided in a follow-up
commit.

MFC after: 1 week

Don't assign, just compare...

Add support for handling ICMP and ICMP6 messages sent in response
to SCTP/UDP/IP and SCTP/UDP/IPv6 packets.

Complete the UDP tunneling of ICMP msgs to those protocols
interested in having tunneled UDP and finding out about the
ICMP (tested by Michael Tuexen with SCTP.. soon to be using
this feature).

Differential Revision: http://reviews.freebsd.org/D5875

Remove a function, which is not used anymore.

Address issues found by the XCode code analyzer.

Put panic() calls under INVARIANTS.

A couple of minor changes that I missed that Michael had done, most noted
in these is the change to non-strict ordering for incoming data (this will
make pkt-drill test 14 fail but its expected).

This is work done by Michael Tuexen and myself at the IETF. This
adds the new I-Data (Interleaved Data) message. This allows a user
to be able to have complete freedom from Head Of Line blocking that
was previously there due to the in-ability to send multiple large
messages without the TSN's being in sequence. The code as been
tested with Michaels various packet drill scripts as well as
inter-networking between the IETF's location in Argentina and Germany.

Improve compilation on windows 64-bit (for the userland stack).

MFC after: 1 week

Add const to several constants. Thanks to Nicholas Nethercote for
providing the patch via
https://bugzilla.mozilla.org/show_bug.cgi?id=1255655

MFC after: 1 week

Whitespace changes.

Improve the teardown of the SCTP stack.

Obtained from: bz@
MFC after: 1 week

sctp_asconf_iterator_end() has an unused second argument; compiles
better if you add it.

Sponsored by: The FreeBSD Foundation

Try to prevent an address (assoc) leak in one way or another when
sctp_initiate_iterator() fails.

Sponsored by: The FreeBSD Foundation

Try to catch a couple of SCTP teardown race conditions.
Saw all the printfs already.

Note: not sure the atomics are needed but without them, the condition
would never trigger, and we'd still see panics (which could have been
due to the insert race). Will work my way backwards in case this stays
stable.

Sponsored by: The FreeBSD Foundation

Store the timer type for logging, because the timer can be freed
during processing the timerout.

MFC after: 3 days

Fix the allocation of outgoing streams:
* When processing a cookie, use the number of
streams announced in the INIT-ACK.
* When sending an INIT-ACK for an existing
association, use the value from the association,
not from the end-point.

MFC after: 1 week

When receiving an SCTP/UDP packet and the interface performed
the UDP checksum computation and signals that it was OK,
clear this bit when passing the packet to SCTP. Since the
bits indicating a valid UDP checksum and a valid SCTP
checksum are the same, the SCTP stack would assume
that also an SCTP checksum check has been performed.

MFC after: 1 week

Fix typos in field names of struct sctp_extrcvinfo.
Provide defines to allow applications to compile.
Thanks to Jens Hoelscher for making me aware of the typos.

MFC after: 1 week

Use __func__ instead of __FUNCTION__.

This allows to compile the userland stack without errors using gcc5.
Thanks to saghul for makeing me aware and providing the patch.

MFC after: 1 week

Add a NULL pointer check to silence the clang code analyzer.

MFC after: 1 week

Use 5 times RTO.Max as the default for the shutdown guard timer
as required by RFC 4960. The sysctl variable can be used to
overwrite this.

Discussed with: rrs
MFC after: 1 week

Fix the exporting of SCTP association states to userland. Without this,
associations in SHUTDOWN-PENDING were never reported correctly.

MFC after: 3 weeks

Provide consistent error causes whenever an ABORT chunk is sent.

MFC after: 1 week

Fix several problems with Stream Reset.
1) We were not handling (or sending) the IN_PROGRESS case if
the other side (or our side) was not able to reset (awaiting more data).
2) We would improperly send a stream-reset when we should not. Not
waiting until the TSN had been assigned when data was inqueue.

Reviewed by: tuexen

Add FIB support for SCTP.
This fixes https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=200379

MFC after: 3 days

Some more debug info cleanup.

MFC after: 3 days

Fix and cleanup the debug information. This has no user-visible changes.
Thanks to Irene Ruengeler for proving a patch.

MFC after: 3 days

Address some compiler warnings. No functional change.

MFC after: 3 days

Fix an accounting bug related to the per stream chunk counter.
While there, don't refer to a net articifically.

MFC after: 3 days

Keep track on the socket lock state. This fixes a bug showing up on
Mac OS X.

MFC after: 3 days

Add a SCTP socket option to limit the cwnd for each path.

MFC after: 1 month

Remove dead code.

Reported by: Coverity
CID: 1018052
MFC after: 1 week

Minimize the usage of SCTP_BUF_IS_EXTENDED.
This should help Robert...

Don't check twice that inp is not NULL.

Reported by: Coverity
CID: 748671
MFC after: 3 days

Fix the support of mapped IPv4 addresses.
Thanks to Mark Bonnekessel and Markus Boese for making me aware of the
problems.
MFC after: 1 week

This is the SCTP specific companion of
https://svnweb.freebsd.org/changeset/base/275358
which was provided by Hans Petter Selasky.

Do the renaming of sb_cc to sb_ccc in a way with less code changes by
using a macro.
This is an alternate approach to
https://svnweb.freebsd.org/changeset/base/275326
which is easier to handle upstream.

Discussed with: rrs, glebius

Merge from projects/sendfile:

o Introduce a notion of "not ready" mbufs in socket buffers. These
mbufs are now being populated by some I/O in background and are
referenced outside. This forces following implications:
- An mbuf which is "not ready" can't be taken out of the buffer.
- An mbuf that is behind a "not ready" in the queue neither.
- If sockbet buffer is flushed, then "not ready" mbufs shouln't be
freed.

o In struct sockbuf the sb_cc field is split into sb_ccc and sb_acc.
The sb_ccc stands for ""claimed character count", or "committed
character count". And the sb_acc is "available character count".
Consumers of socket buffer API shouldn't already access them directly,
but use sbused() and sbavail() respectively.
o Not ready mbufs are marked with M_NOTREADY, and ready but blocked ones
with M_BLOCKED.
o New field sb_fnrdy points to the first not ready mbuf, to avoid linear
search.
o New function sbready() is provided to activate certain amount of mbufs
in a socket buffer.

A special note on SCTP:
SCTP has its own sockbufs. Unfortunately, FreeBSD stack doesn't yet
allow protocol specific sockbufs. Thus, SCTP does some hacks to make
itself compatible with FreeBSD: it manages sockbufs on its own, but keeps
sb_cc updated to inform the stack of amount of data in them. The new
notion of "not ready" data isn't supported by SCTP. Instead, only a
mechanical substitute is done: s/sb_cc/sb_ccc/.
A proper solution would be to take away struct sockbuf from struct
socket and allow protocols to implement their own socket buffers, like
SCTP already does. This was discussed with rrs@.

Sponsored by: Netflix
Sponsored by: Nginx, Inc.

Add context pointer and source address to the UDP tunnel callback

These are needed for the forthcoming vxlan implementation. The context
pointer means we do not have to use a spare pointer field in the inpcb,
and the source address is required to populate vxlan's forwarding table.

While I highly doubt there is an out of tree consumer of the UDP
tunneling callback, this change may be a difficult to eventually MFC.

Phabricator: https://reviews.freebsd.org/D383
Reviewed by: gnn

Add a explict cast to silence a warning when building
the userland stack on Windows.
This issue was reported by Peter Kasting from Google.

MFC after: 3 days

Use union sctp_sockstore instead of struct sockaddr_storage. This
eliminiates some warnings when building in userland.
Thanks to Patrick Laimbock for reporting this issue.
Remove also some unnecessary casts.
There should be no functional change.

MFC after: 1 week

Add support for the SCTP_PR_STREAM_STATUS and SCTP_PR_ASSOC_STATUS
socket options. This includes managing the correspoing stat counters.
Add the SCTP_DETAILED_STR_STATS kernel option to control per policy
counters on every stream. The default is off and only an aggregated
counter is available. This is sufficient for the RTCWeb usecase.

MFC after: 1 week

Add support for the SCTP_AUTH_SUPPORTED and SCTP_ASCONF_SUPPORTED
socket options. Add also a sysctl to control the support of ASCONF.

MFC after: 1 week

Add support for the SCTP_RECONFIG_SUPPORTED and the corresponding
sysctl controlling the negotiation of the RE-CONFIG extension.

MFC after: 3 days

Add support for the SCTP_PKTDROP_SUPPORTED socket option and
the corresponding sysctl variable.
The default is off, since the specification is not an RFC yet.

MFC after: 1 week

Add SCTP socket option SCTP_NRSACK_SUPPORTED to control the
NRSACK extension. The default will still be off, since it
it not an RFC (yet).
Changing the sysctl name will be in a separate commit.

MFC after: 1 week

Add support for the SCTP_PR_SUPPORTED socket option as specified in
http://tools.ietf.org/html/draft-ietf-tsvwg-sctp-prpolicies
Add also a sysctl controlling the default of the end-points.

MFC after: 1 week

Cleanup the ECN configuration handling and provide an SCTP socket
option for controlling ECN on future associations and get the
status on current associations.
A simialar pattern will be used for controlling SCTP extensions in
upcoming commits.

Cleanup sctp_send_initiate() and sctp_send_initiate_ack() to be
in sync as much as possible. This simplifies upcoming changes.

Initialize notification strucuture. This was missed in an earlier commit

MFC after: 3 days

Initialize SCTP cmsg's and notification's buffer before copying out
to userland.

Submitted by: tuexen
Security: CVE-2014-3953
Security: FreeBSD-SA-14:17.kmem

Honor jails for unbound SCTP sockets when selecting source addresses,
reporting IP-addresses to the peer during the handshake, adding
addresses to the host, reporting the addresses via the sysctl
interface (used by netstat, for example) and reporting the
addresses to the application via socket options.
This issue was reported by Bernd Walter.

MFC after: 3 days

Send also a packet containing an ABORT chunk in response to an OOTB packet
containing a COOKIE-ECHO chunk.

MFC after: 3 days

Send the correct error cause, when a DATA chunk with no user data
is received. This bug was reported by Irene Ruengeler.

MFC after: 3 days

* Provide information in error causes in ASCII instead of
proprietary binary format.
* Add support for a diagnostic information error cause.
The code is sysctlable and the default is 0, which
means it is not sent.

This is joint work with rrs@.

MFC after: 1 week

Address some warnings which showed up on the userland version.

MFC after: 1 week

Use htons()/ntohs() appropriately.
These issues were reported by Andrew Galante.

MFC after: 3 days

Changes from upstream to improve compilation when INET or INET6
or none of them is defined.

MFC after: 3 days

Remove redundant field pr_sctp_on.

MFC after: 1 week

Use LIST_EMPTY when appropriate.

MFC after: 1 week

Remove redundant checks.

MFC after: 2 weeks

Set errno to ETIMEDOUT if an SCTP association times out during
setup.

MFC after: 1 week

Fix a potential race in returning setting errno when an
association goes down.
Reported by Mozilla in
https://bugzilla.mozilla.org/show_bug.cgi?id=845513

MFC after: 3 days

Cleanup the handling of address scopes. Announce in the INIT/INIT-ACK
only the supported address types. While there, do some whitespace
cleanups.

MFC after: 1 week

Fix a copy and paste error.

MFC after: 3 days

Mechanically substitute flags from historic mbuf allocator with
malloc(9) flags within sys.

Exceptions:

- sys/contrib not touched
- sys/mbuf.h edited manually

Add support for SCTP/UDP/IPV6.
This completes the support of
http://tools.ietf.org/html/draft-ietf-tsvwg-sctp-udp-encaps

MFC after: 1 week

Get the accounting working. We now have counters how many
chunks for each SCTP outgoing stream are in the send and
sent queue.
While there, improve the naming of NR-SACK related constants
recently introduced.

MFC after: 1 week

Add per outgoing stream accounting for chunks in the send
and sent queue. This provides no functional change, but is
a preparation for an upcoming stream reset improvement.
Done with rrs@.

MFC after: 1 week

Fix possible spurious sbunlock in sctp_sorecvmsg.

Reviewed by: tuexen
Approved by: trasz (mentor)
MFC after: 3 days

Move from early SSN assignment to late SSN assignment.
This doesn't change functionality, but makes upcoming change
much easier.
Developed with rrs@ at the IETF 85.

MFC after: 1 week

Use ntohs() and htons() in correct order. However, this doesn't change
functionality.

Switch the entire IPv4 stack to keep the IP packet header
in network byte order. Any host byte order processing is
done in local variables and host byte order values are
never[1] written to a packet.

After this change a packet processed by the stack isn't
modified at all[2] except for TTL.

After this change a network stack hacker doesn't need to
scratch his head trying to figure out what is the byte order
at the given place in the stack.

[1] One exception still remains. The raw sockets convert host
byte order before pass a packet to an application. Probably
this would remain for ages for compatibility.

[2] The ip_input() still subtructs header len from ip->ip_len,
but this is planned to be fixed soon.

Reviewed by: luigi, Maxim Dounin <mdounin mdounin.ru>
Tested by: ray, Olivier Cochard-Labbe <olivier cochard.me>

Small cleanups. No functional change.

MFC after: 10 days

Using %p in a format string requires a void *.

MFC after: 10 days

Whitespace change.

MFC after: 3 days

Fix a typo which results in RTT to be off by a factor of 10, if the RTT is
larger than 1 second.

MFC after: 3 days

Fix a refcount bug when freeing an association.
While there: Change code to be consistent.
Discussed with rrs@.
MFC after: 3 days

#ifdef INET and INET6 consistently. This also fixes a bug, where
it was done wrong.

MFC after: 3 days

Provide the correct notification type (SCTP_SEND_FAILED_EVENT)
for unsent messages.

MFC after: 3 days

Pass the src and dst address of a received packet explicitly around.

MFC after: 3 days

Whitespace cleanup.

MFC after: 3 days

Cleanup the UDP decapsulation code.

MFC after: 3 days

Pass flowid explicitly through the stack instead of taking it from
the mbuf chain at different places.
While there: Fix several bugs related to VRFs.

MFC after: 3 days

Small cleanup.

MFC after: 3 days

Remove an unused parameter.

MFC after: 3 days

Use consistent text at the begining of the files.

MFC after: 3 days

Support SCTP_REMOTE_ERROR notification.

MFC after: 3 days

Provide in the SCTP_SEND_FAILED and SCTP_SEND_FAILED_EVENT notifications
the correct ssf_error or ssfe_error as required by RFC 6458.

MFC after: 3 days

Remove unused constants.

MFC after: 3 days

Use ECONNABORTED in cases where the ABORT was sent to the peer.

MFC after: 3 days

Ensure the user can read COMM_LOST notifications on 1-to-1 style sockets.

MFC after: 3 days

Provide in the association change notification the received ABORT chunk
if case of SCTP_COMM_LOST or SCTP_CANT_STR_ASSOC as required by RFC 6458.

MFC after: 3 days

Only provide the supported features in the SCTP_ASSOC_CHANGE notif
if the state is SCTP_COMM_UP or SCTP_RESTART.
While there, do some cleanups.

MFC after: 3 days

Address clang warnings.

MFC after: 3 days

Add support for the sac_info field in struct sctp_assoc_change
as required by RFC 6458.

MFC after: 3 days

Remove debug code.

MFC after: 3 days

Add support for SCTP_SEND_FAILED_EVENT as required by RFC 6458.

MFC after: 3 days

Provide the flags in the SCTP stream reconfig related notification
as specified in RFC 6525.

MFC after: 3 days

Add support for SCTP_STREAM_CHANGE_EVENT, SCTP_ASSOC_RESET_EVENT as
required by RFC 6525. This also fixes SCTP_STREAM_RESET_EVENT.

MFC after: 3 days

Use SCTP_PRINTF() instead of printf() in all SCTP sources.

MFC after: 3 days

Fix a type in an SCTP AUTH related notification. Keep the old name
for backwards compatibility.
Spotted by Irene Ruengeler.

MFC after: 3 days

Use the flags defined in RFC 6525 in the stream reset event.

Fix check used by stream reset related events.

MFC after: 3 days

Fix reported errno.

MFC after: 3 days

Make stream our stream reset implementation
compliant to RFC6525.

MFC after: 1 month

Small cleanup of the code. No functional change (in FreeBSD kernel).

MFC after: 1 week.

Two cleanups. No functional change.

Add an SCTP sysctl "blackhole", similar to the one for TCP.
If set to 1, no ABORT is sent back in response to an incoming
INIT. If set to 2, no ABORT is sent back in response to
an out of the blue packet. If set to 0 (the default), ABORTs
are sent.
Discussed with rrs@.

MFC after: 1 month.

Use NULL instead of 0.

MFC after: 1 month.

Address issues found by clang. While there, fix also some style
issues.

MFC after: 3 months.

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

MFC after: 3 months.

Add support for the SCTP_REMOTE_UDP_ENCAPS_PORT socket option.
Retire the the now unused sctp_udp_tunneling_for_client_enable
sysctl variable.

MFC after: 3 months.

Update the inp stored in a HB-timer when moving an stcb to a new inp.
Use only this stored inp when processing a HB timeout.
This fixes a bug which results in a crash.

MFC after: 3 days.

Cleanup the iterator code, remove code that is never executed.

Approved by: re
MFC after: 1 month.

Fix the enabling/disabling of Heartbeats and path MTU
discovery when using the SCTP_PEER_ADDR_PARAMS socket option.
Approved by: re
MFC after: 1 month.

Make sure that SCTP rejects broadcast, multicast and wildcard addresses
as remote addresses.

Approved by: re
MFC after: 1 month.

Ensure that 1-to-1 style SCTP sockets can only be connected once.
Allow implicit setup also for 1-to-1 style sockets as described
in the latest version of the socket API ID.

Approved by: re
MFC after: 1 month

Fix the handling of the flowlabel and DSCP value in the SCTP_PEER_ADDR_PARAMS
socket option.
Honor the net.inet6.ip6.auto_flowlabel sysctl setting.

Approved by: re (bz)
MFC after: 1 month.

Add support for the spp_dscp field in the SCTP_PEER_ADDR_PARAMS
socket option. Backwards compatibility is provided by still
supporting the spp_ipv4_tos field.

Approved by: re@
MFC after: 2 months.

The result of a joint work between rrs@ and myself at the IETF:
* Decouple the path supervision using a separate HB timer per path.
* Add support for potentially failed state.
* Bring back RTO.min to 1 second.
* Accept packets on IP-addresses already announced via an ASCONF
* While there: do some cleanups.

Approved by: re@
MFC after: 2 months.

Add support for the newly added SCTP API.
In particular add support for:
* SCTP_SNDINFO, SCTP_PRINFO, SCTP_AUTHINFO, SCTP_DSTADDRV4, and
SCTP_DSTADDRV6 cmsgs.
* SCTP_NXTINFO and SCTP_RCVINFO cmgs.
* SCTP_EVENT, SCTP_RECVRCVINFO, SCTP_RECVNXTINFO and SCTP_DEFAULT_SNDINFO
socket option.
* Special association ids (SCTP_FUTURE_ASSOC, ...)
* sctp_recvv() and sctp_sendv() functions.

MFC after: 1 month.

Get rid of unused functions.

MFC after: 1 week.

Fix a locking issue showing up on Mac OS X when subscribing to
authentication events. DTLS/SCTP renegotiations trigger the bug.

MFC after: 2 weeks.

Remove code with any effect.

Some more cleanups related to an kernel without INET.

MFC after: 1 week

Improve compilation of SCTP code without INET support.
Some bugs where fixed while doing this:
* ASCONF-ACK messages might use wrong port number when using
IPv6.
* Checking for additional addresses takes the correct address
into account and also does not do more comparisons than
necessary.

This patch is based on one received from bz@ who was
sponsored by The FreeBSD Foundation and iXsystems.

MFC after: 1 week

Tunes and fixes the new DC-CC to seem to hit the
right mix. Still may need some tweaks but it
appears to almost not give away too much to an
RFC2581 flow, but can really minimize the amount of
buffers used in the net.

MFC after: 3 months

Improvements to CC modules:
1) Add four new points that allow you to get more information
to cc algo's
2) Fix the case where user changes module on a existing TCB, in
such a case, the initialization module needs to be called on all nets.
3) Move htcp_cc structure to a union that other modules can use.
4) Add 5th point for get/set socket options for cc_module specific options

MFC after: 2 months

* Cleanup the code computing the retransmission timeout.
* Fix an initialization bug for the scaled variance of the RTO.

MFC after: 3 months.

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

Fix several bugs in the stream schedulers.
From Robin Seggelmann.

MFC after: 3 months.

Make sure that changing the ECN sysctl does not affect
exisiting associations and endpoints.

MFC after: 3 months.

1) Allow a chunk to track the cwnd it was at when sent.
2) Add separate max-bursts for retransmit and hb. These
are set to sysctlable values but not settable via the
socket api. This makes sure we don't blast out HB's or
fast-retransmits.
3) Determine on the first data transmission on a net if
its local-lan (by being under or over a RTT). This
can later be used to think about different algorithms
based on locallan vs big-i (experimental)
4) The cwnd should NOT be allowed to grow when an ECNEcho
is seen (TCP has this same bug). We fix this in SCTP
so an ECNe being seen prevents an advance of cwnd.
5) CWR's should not be sent multiple times to the
same network, instead just updating the TSN being
transmitted if needed.

MFC after: 1 Month

More ECN fixes:
1) We now remove ECN-Nonce since it will no longer continue as a I-D
2) Eliminate last_tsn_echo, this tied us to an assoc not the net
and thus we were not doing m-homing on the ECN-Echo senders side right.
3) Increment the count going out even if the TSN in lower in the pending
ECN-Echo, this way the receiver knows exactly how many packets were
marked even with network re-ordering
4) Fix so we DO NOT stop doing delayed sack if a ECN Echo is in queue
MFC after: 1 month

Fixes to ECN in SCTP.
1) ECN was on an association basis, this is incorrect and
will not work with CMT or for that matter if the user
is sending to multiple addresses. This commit makes
ECN on a per path basis.
2) Adopt the new format for the ECN internet draft. This also
maintains compatability with old format chunks as well.
3) Keep track of the real time of a RTT down to micro seconds.
For some future conditional features (for like a data center
this is good information to have).
MFC after: 1 month

Keep track of the real last RTT on each net.
This will be used for Data Center congestion
control, we won't want to engage it in the
ECN code unless we KNOW that the RTT is less
than 500us.

MFC after: 1 week

Add stream scheduling support.
This work is based on a patch received from Robin Seggelmann.

MFC after: 3 months.

Remove unnecessary checking of variable.

MFC after: 3 months.

Cleanup the management of CC functions.

MFC after: 3 months.

Code cleanup: Use LIST_FOREACH, LIST_FOREACH_SAFE, TAILQ_FOREACH,
TAILQ_FOREACH_SAFE where appropriate.
No functional change.

MFC after: 3 months.

Bugfix: Do correct accounting using the MIB counters when an
association is aborted via sctp_abort_association().

MFC after: 3 days.

Don't print an empty line when printing mapping arrays.

MFC after: 3 days.

Fix a bug which resulted in kevent() reporting an event twice on
1-to-1 style sockets when an ABORT was received.

MFC after: 3 days.

Do not have the MTU table twice in the code. Therefore move the
function from the timer code to util, rename it appropriately and
also fix a bug in sctp_get_prev_mtu(), where calling it with a
value existing in the MTU table did not return a smaller one.

MFC after: 3 days.

Not only stop all timers when entering the SHUTDOWN_SENT state,
but also when entering the SHUTDOWN_ACK_SEND state.

MFC after: 3 days.

A new jail(8) with a configuration file, to replace the work currently done
by /etc/rc.d/jail.

Remove old debug code.

MFC after: 2 weeks.

Remove unused variable/assignment.

MFC after: 3 weeks.

Delay the assignment of a path for DATA chunk until they hit
the sent_queue. Honor a given path when the SCTP_ADDR_OVER
flag is set.

MFC after: 2 weeks.

Fix some CLANG warnings. One clang warning is left
due to the fact that its bogus.. nam->sa_family will
not change from AF_INET6 to AF_INET (but clang
thinks it does ;-D)

Fix the switching on/off of CMT using sysctl and socket option.
Fix the switching on/off of PF and NR-SACKs using sysctl.
Add minor improvement in handling malloc failures.
Improve the address checks when sending.

MFC after: 4 weeks

This fixes a crash in SCTP. It was possible to have a
large number of packets queued to a crashing process.
In a specific case you may get 2 ABORT's back (from
say two packets in flight). If the aborts happened to
be processed at the same time its possible to have
one free the association while the other is trying
to report all the outbound packets. When this occured
it could lead to a crash.

MFC after: 3 days

Fix a rece condition in the shutdown handling.
The race condition resulted in a panic.

MFC after: 3 days

MFC 209029

3 Fixes -
a) There was a case where a ICMP message could cause
us to return leaving a stuck lock on an stcb.
b) The iterator needed some tweaks to fix its lock
ordering.
c) The ITERATOR_LOCK is no longer needed in the freeing
of a stcb. Now that the timer based one is gone we don't
have a multiple resume situation. Add to that that there
was somewhere a path out of the freeing of an assoc that
did NOT release the iterator_lock.. it was time to clean
this old code up and in the process fix the lock bug.

Approved by: re (bz)

3 Fixes -
a) There was a case where a ICMP message could cause
us to return leaving a stuck lock on an stcb.
b) The iterator needed some tweaks to fix its lock
ordering.
c) The ITERATOR_LOCK is no longer needed in the freeing
of a stcb. Now that the timer based one is gone we don't
have a multiple resume situation. Add to that that there
was somewhere a path out of the freeing of an assoc that
did NOT release the iterator_lock.. it was time to clean
this old code up and in the process fix the lock bug.

MFC after: 1 week

MFC:
Fix a number of bugs and race conditions.
r208160: Bring back of the iterator thread. It now properly handles VNETS
having only one thread. The old timer based code was full of
LOR's and other issues.

r208852: Cleanup bug. Basically when an un-accepted socket was hanging on a
closed listener, we would leak the inp never cleaning it up

r208853: Enhance the use under invarients of the audit for locks function
and fix a bug where a close collision with a cookie being processed
would cause a crash.

r208854: Use the proper increment macros when working with the
sent_queue_retran_cnt

r208855: Align comments properly, Fix a bug where we were NOT looking at the
resend markings for control chunks and also not decrementing the
retran count which caused extra calls to retransmission. Alos add
a valid no locks call to the output routine.

r208856: Spacing issues in auth/bsd addr.

r208857: Get rid of a windows ifdef that somehow leaked in

r208863: Missing error leg returns in some failure cases

r208864: LOR fix between the iterator and sctp_inpcb_close

r208874: Don't call the sctp_inpcb_free from abort an association since you
don't know what locks you hold and a timer will take care of the
situation when the gone flag is set

r208875: sctp_inpcb_free bug - a socket under the right situation could get
stuck (from the accept queue) and never start the proper cleanup
timer)

r208876: Further enhance invariant lock validation, Fix a bug where a closed
socket and a INIT-ACK could collide and cause a crash

r208878: Clear up another bug in sctp_inpcb_free where we would end up due
to a race in freeing hit a destroy of a contended lock.

r208879: Optimize the cleanup and make some additional fixes in the sysctl
code so that it won't reference a GONE INP and crash us

r208883 & r208891: Fix so we don't open a hole between a sock lock and a call
to socantrcvmore.. we could before hit a race that would kill the
socket underneath us leading to a crash

r208897: CUM-ACK calculation was messed up. So basically large message got
broken from the original NR_sack integration.

r208902: Make sure that we don't move a bit to the NR array that is behind
the cum-ack

r208952: Use both bit maps to calculte the cum-ack.

r208953: Fix bug having to do with freeing an sctp_inpcb_free().
1) make sure not to remove the flag until you get the lock again.
2) make sure all log_closing calls hold the lock.
3) Release all the locks when everthing is done and call callout_drain
not callout_stop..

r208970: Fix some places on user allocation of a new sctp_inpcb where we run
out of resource that we make sure to NULL the so_pcb pointer.
Approved by: re - (bz@freebsd.org)

Ok, yet another bug in killing off all the hundreds
of apitesters.. Basically we end up with attempting
to destroy a lock thats contended on. A cookie echo
arrives at the same time that the close is happening.
The close gets the lock but the cookie echo has already
passed the check for the gone flag and is then locked
waiting on the create lock.. when we go to destroy it
bam. For now we do the timer destroy for all calls
to close.. We can probably optimize this later so that
we check whats being contended on and if there is contention
then do the timer thing. but this is probably safest since
the inp has been removed from all lists and references and
only the timer can find it.. once the locks are released all
other places will instantly see the GONE flag and bail (thats
what the change in sctp_input is one place that was lacking
the bail code).

MFC after: 1 week

Fix a bug in sctp_abort_assoc(). DON'T call the sctp_inpcb_free
when the gone flag is set. You don't know what locks the
caller has set and there is already a kill timer running.

MFC after: 1 week

Purge out a Windows def that somehow slipped
past the scrubber.

MFC after: 1 Week

This adds back the Iterator to the sctp
code base. We now properly have ONE thread
that services all VNET's. Also we purge out
the old timer based iterator code which had
multiple LOR's and other issues.

MFC after: 3 days

MFC 206758, 206840, 206891, 206892, 207099, 207191, 207197
* Fix a bug where SACKs are not sent when they should.
* Get delayed SACK working again.
* Really print the nr_mapping array when it should be printed.
* Update highest_tsn variables when sliding mapping arrays.
* Sending a FWDTSN chunk should not affect the retran count.
* Cleanups.

* Fix compilation when using SCTP_AUDITING_ENABLED.
* Fix delaying of SACK by taking out old optimization code
which does not optimize anymore.
* Fix fast retransmission of chunks abandoned by the
"number of retransmissions" policy.

MFC after: 3 days.

Really print the nr_mapping array when it should be printed.`

MFC after: 3 days.

MFC of 206281

Final MFC of all the IETF hack a-thon.. head and stable are
now in sync ;-)

MFC of 206137

This is Part III of the great IETF hack-a-thon to fix
the NR-Sack code. (the last one on the cpu options
was a lull.. i.e MFC 205629).. still 2 more to go.

MFC of 205627

Part II (more to follow) of the great IETF hack-a-thon to
fix the NR-Sack code.

MFC of 204096

One of Michaels changes to fix some sign issues and
some minor locking.

MFC of 205502

The firste of Michael and my long fight at the IETF to
get the NR sack code fixed and aligned.

MFC 202521

More stray ifdef's that had worked their way into the
code base somehow (yes thats ifdef Windows going out.. our
stack runs on windows .. big thanks for that goes to
Kozuka-san and Bruce Cran ;-D)

Fix a off-by-one bug in zeroing out the mapping arrays.
Fix sctp_print_mapping_array().

MFC after: 1 week

* Fix some race condition in SACK/NR-SACK processing.
* Fix handling of mapping arrays when draining mbufs or processing
FORWARD-TSN chunks.
* Cleanup code (no duplicate code anymore for SACKs and NR-SACKs).
Part of this code was developed together with rrs.
MFC after: 2 weeks.

Fix for NR-Sack code. The code was NOT working properly when
enabled. Basically most of the operations were incorrect causing
bad sacks when you enabled nr-sack. The fixes range across
4 files and unifiy most of the processing so that we only test
nr_sack flags to decide which type of sack to generate.

Optimization left for this is to combine the sack generation
code and make it capable of generating either sack thus shrinking
out a routine.

Reviewed by: tuexen@freebsd.org

Fixes a bug where SACKs in the face of
mapping_array expansion would break. Basically
once we expanded the array we no longer had both
mapping arrays in sync which the sack processing code depends on.
This would mean we were randomly referring to memory that was probably
not there. This mostly just gave us bad sack results going back to the peer.
If INVARIENTS was on of course we would hit the panic routine in the sack_check
call.

We also add a print routine for the place where one would panic in
invarients so one can see what the main mapping array holds.

Reviewed by: tuexen@freebsd.org
MFC after: 2 weeks

* Fix another u_long -> uint32_t issue.
* Remove an unused global variable.
* Fix an issue reported by Bruce Cran related to reusing SCTP socket which
where connected.

MFC after: 1 week

MFC a number of changes from head for ISP (203478,203463,203444,202418,201758,
201408,201325,200089,198822,197373,197372,197214,196162). Since one of those
changes was a semicolon cleanup from somebody else, this touches a lot more.

Pulls out another leaked windows ifdef that somehow
made its way through the scrubber.

MFC 199459

Get rid of unused fields addr_over which is never really used,
only copied around.

MFC 199369

Do not hold the lock longer than necessary.

Remove extraneous semicolons, no functional changes.

Submitted by: Marc Balmer <marc@msys.ch>
MFC after: 1 week

MFC 197288,197326,197327,197328,197342,197914,197929,
197955,199365,199370,199371,199373,199866
This MFCs all SCTP/VNET relevant fixes from head.

Approved by: rrs (mentor)

Get rid of unused fields addr_over which is never really used,
only copied around.

Approved by: rrs (mentor)

Do not hold the lock longer than necessary.

Approved by: rrs (mentor)
MFC after: 1 month

Get SCTP working in combination with VIMAGE.
Contains code from bz.
Approved by: rrs (mentor)
MFC after: 1 month.

Fix a bug in the handling of unreliable messages which
results in stalled associations.

Approved by: re, rrs (mentor)

Fix a bug in the handling of unreliable messages
which results in stalled associations.

Approved by: re, rrs (mentor)
MFC after: immediately

MFC r196260.
* Fix a bug where PR-SCTP settings are ignore when using implicit
association setup.
* Fix a bug where message with illegal stream ids are not deleted.
* Fix a crash when reporting back unsent messages from the send_queue.
* Fix a bug related to INIT retransmission when the socket is already
closed.
* Fix a bug where associations were stalled when partial delivery API
was enabled.
* Fix a bug where the receive buffer size was smaller than the
partial_delivery_point.

Approved by: re, rrs (mentor)

* Fix a bug where PR-SCTP settings are ignore when using implicit
association setup.
* Fix a bug where message with illegal stream ids are not deleted.
* Fix a crash when reporting back unsent messages from the send_queue.
* Fix a bug related to INIT retransmission when the socket is already
closed.
* Fix a bug where associations were stalled when partial delivery API
was enabled.
* Fix a bug where the receive buffer size was smaller than the
partial_delivery_point.

Approved by: re, rrs (mentor)
MFC after: One day.

Turns out that when a receiver forwards through its TNS's the
processing code holds the read lock (when processing a
FWD-TSN for pr-sctp). If it finds stranded data that
can be given to the application, it calls sctp_add_to_readq().
The readq function also grabs this lock. So if INVAR is on
we get a double recurse on a non-recursive lock and panic.

This fix will change it so that readq() function gets a
flag to tell if the lock is held, if so then it does not
get the lock.

Approved by: re@freebsd.org (Kostik Belousov)
MFC after: 1 week

Add a missing unlock for the inp lock when
returning early from sctp_add_to_readq().

Approved by: re, rrs (mentor)
MFC after: 2 weeks.

Fix a small memory leak from the nr-sack code - the mapping array
was not being freed at term of association. Also get rid of
the MICHAELS_EXP code.

Many bug fixes (from the IETF hack-fest):
- PR-SCTP had major issues when skipping through a multi-part message.
o Did not look at socket buffer.
o Did not properly handle the reassmebly queue.
o The MARKED segments could interfere and un-skip a chunk causing
a problem with the proper FWD-TSN.
o No FR of FWD-TSN's was being done.
- NR-Sack code was basically disabled. It needed fixes that
never got into the real code.
- CMT code had issues when the two paths were NOT the same b/w. We
found a few small bugs, but also the critcal one here was not
dividing the rwnd amongst the paths.

Obtained from: Michael Tuexen and myself at the IETF hack-fest ;-)

Fixes several PR-SCTP releated bugs.
- When sending large PR-SCTP messages over a
lossy link we would incorrectly calculate the fwd-tsn
- When receiving large multipart pr-sctp packets we would
incorrectly send back a SACK that would renege improperly
on already received packets thus causing unneeded retransmissions.

Add the add-stream capability. Still needs more
testing..

MFC after: 1 month

Fix INET only build breakage with SCTP - pointy hat to me :-)

- 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

Code from the hack-session known as the IETF (and a
bit of debugging afterwards):
- Fix protection code for notification generation.
- Decouple associd from vtag
- Allow vtags to have less strigent requirements in non-uniqueness.
o don't pre-hash them when you issue one in a cookie.
o Allow duplicates and use addresses and ports to
discriminate amongst the duplicates during lookup.
- Add support for the NAT draft draft-ietf-behave-sctpnat-00, this
is still experimental and needs more extensive testing with the
Jason Butt ipfw changes.
- Support for the SENDER_DRY event to get DTLS in OpenSSL working
with a set of patches from Michael Tuexen (hopefully heading to OpenSSL soon).
- Update the support of SCTP-AUTH by Peter Lei.
- Use macros for refcounting.
- Fix MTU for UDP encapsulation.
- Fix reporting back of unsent data.
- Update assoc send counter handling to be consistent with endpoint sent counter.
- Fix a bug in PR-SCTP.
- Fix so we only send another FWD-TSN when a SACK arrives IF and only
if the adv-peer-ack point progressed. However we still make sure
a timer is running if we do have an adv_peer_ack point.
- Fix PR-SCTP bug where chunks were retransmitted if they are sent
unreliable but not abandoned yet.

With the help of: Michael Teuxen and Peter Lei :-)
MFC after: 4 weeks

-Improvement: Add '\n' on debug output in sctp_lower_sosend().
-Improvement: panic() on INVARIANTS kernels if memory allocation
fails for a tagblock in sctp_add_vtag_to_timewait().
-Bugfix: Protect code in sctp_is_in_timewait() by
SCTP_INP_INFO_WLOCK/SCTP_INP_INFO_WUNLOCK.
-Cleanup: Get rid of unused variable now in sctp_init_asoc().
-Bugfix: Reuse the correct vtag in sctp_add_vtag_to_timewait().
-Cleanup: Get rid of unused constant SCTP_TIME_WAIT_SHORT
in sctp_constants.h.
-Improvement: Use all hash buckets of the vtag hash table.
-Cleanup: Get rid of then unused constant SCTP_STACK_VTAG_HASH_SIZE_A.
-Bugfix: Handle SHUTDOWN;SACK packet correctly.
-Bugfix: Last TSN in a gap ack block was not being "ack'd"
in the internal scoreboard.
Obtained from: (with help from Michael Tuexen)

- Import the HEAD csup code which is the basis for the cvsmode work.

The flags value was not always being copied out in the recv routine like it
should be.
Obtained from: Michael Tuexen

- Make strict-sacks be the default.
- Change it so that without INVARIANTs there are
no panics in SCTP.
- sctp_timer changes so that we have a recovery mechanism
when the sent list is out of order.

Adds support for the SCTP_PORT_REUSE option
Fixes a refcount bug found in the process

Obtained from: With the help of Michael Tuexen

- Out with some printfs.
- Fix a initialization of last_tsn_used
- Fix handling of mapped IPv4 addresses
Obtained from: Michael Tuexen and I :-)
MFC after: 1 week

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!

- Macro-izes the packed declaration in all headers.
- Vimage prep - these are major restructures to move
all global variables to be accessed via a macro or two.
The variables all go into a single structure.
- Asconf address addition tweaks (add_or_del Interfaces)
- Fix rwnd calcualtion to be more conservative.
- Support SACK_IMMEDIATE flag to skip delayed sack
by demand of peer.
- Comment updates in the sack mapping calculations
- Invarients panic added.
- Pre-support for UDP tunneling (we can do this on
MAC but will need added support from UDP to
get a "pipe" of UDP packets in.
- clear trace buffer sysctl added when local tracing on.

Note the majority of this huge patch is all the vimage prep stuff :-)

- sctputil.c - If debug is on, the INPKILL timer can deref a freed value.
Change so that we save off a type field for display and
NULL inp just for good measure.

- sctp_output.c - Fix it so in sending to the loopback we use the
src address of the inbound INIT. We don't want
to do this for non local addresses since otherwise
we might be ingressed filtered so we need to use
the best src address and list the address sent to.

Obtained from: time bug - Neil Wilson
MFC after: 1 week

- Adds support for the multi-asconf (From Kozuka-san)
- Adds some prepwork (Not all yet) for vimage in particular
support the delete the sctppcbinfo.xx structs. There is
still a leak in here if it were to be called plus we stil
need the regrouping (From Me and Michael Tuexen)
- Adds support for UDP tunneling. For BSD there is no
socket yet setup so its disabled, but major argument
changes are in here to emcompass the passing of the port
number (zero when you don't have a udp tunnel, the default
for BSD). Will add some hooks in UDP here shortly (discussed
with Robert) that will allow easy tunneling. (Mainly from
Peter Lei and Michael Tuexen with some BSD work from me :-D)
- Some ease for windows, evidently leave is reserved by their
compile move label leave: -> out:

MFC after: 1 week

- Define changes in sctp.h
- Bug in CA that does not get us incrementing the PBA properly which
made us more conservative.
- comment updated in sctp_input.c
- memsets added before we log
- added arg to hmac id's
MFC after: 2 weeks

Allow SCTP to compile without INET6.
PR: 116816
Obtained from tuexen@fh-muenster.de:
MFC after: 2 weeks

Correct two problems relating to sorflush(), which is called to flush
read socket buffers in shutdown() and close():

- Call socantrcvmore() before sblock() to dislodge any threads that
might be sleeping (potentially indefinitely) while holding sblock(),
such as a thread blocked in recv().

- Flag the sblock() call as non-interruptible so that a signal
delivered to the thread calling sorflush() doesn't cause sblock() to
fail. The sblock() is required to ensure that all other socket
consumer threads have, in fact, left, and do not enter, the socket
buffer until we're done flushin it.

To implement the latter, change the 'flags' argument to sblock() to
accept two flags, SBL_WAIT and SBL_NOINTR, rather than one M_WAITOK
flag. When SBL_NOINTR is set, it forces a non-interruptible sx
acquisition, regardless of the setting of the disposition of SB_NOINTR
on the socket buffer; without this change it would be possible for
another thread to clear SB_NOINTR between when the socket buffer mutex
is released and sblock() is invoked.

Reviewed by: bz, kmacy
Reported by: Jos Backus <jos at catnook dot com>

- More fixes for lock misses on the transfer of data to
the sent_queue. Sometimes I wonder why any code
ever works :-)
- Fix the pad of the last mbuf routine, It was working improperly
on non-4 byte aligned chunks which could cause memory overruns.

MFC after: 1 week

- optimize the initialization of the SB max variables.
- Missing lock when sending data and moving it to the
outqueue.
- If a mbuf alloc fails during moving to outqueue the
reassembly of the old mbuf chain was incorrect.
- some_taken becomes a counter in sctputil.c instead of a set to 1.
- Fix a panic to be only under invarients and have a proper recovery.
- msg_flags needed to be set.to the value collected not or'd.

MFC after: 1 week

- Found a problem in non-blocking sends. When
sending, once the locks are all unlocked to
do the copy's in, its possible that other
events could then raise the number of bytes
outstanding pushing it so not all the message
would fit. This would then cause us to send
only part of the message. This fix makes it
so we keep a "reserved" amount that can be
kept in mind when making calculations to send.
- rcv msg args with a NULL/NULL for to/tolen will return an error incorrectly
for the 1-2-1 model.
- We were not doing 0 len return correctly and not setting cantrcv more
correctly. Previouly we "fixed" this area by taking out the socantrcv
since we then could not get the data out. The correct rix is to still
flag the socket but alow a by-pass route to continue to read until
all data is consumed.

MFC after: 1 week

- Fix a bug in sctp_calc_rwnd() which resulted in wrong rwnd predictions.
- Fix a signedness problem that shows up in some 64 bit platforms (macos).

MFC after: 1 week

- Change the Time Wait of vtags value to match the cookie-life
- Select a tag gains ability to optionally save new tags
off in the timewait system.
- When looking up associations do not give back a stcb that
is in the about-to-be-freed state, and instead continue
looking for other candiates.
- New function to query to see if value is in time-wait.
- Timewait had a time comparison error that caused very
few vtags to actually stay in time-wait.
- When setting tags in time-wait, we now use the time
requested NOT a fixed constant value.
- sstat now gets the proper associd when we do the query.
- When we process an association, we expect the tag chosen
(if we have one from a cookie) to be in time-wait. Before
we would NOT allow the assoc up by checking if its good.
In theory this should have caused almost all assoc not
to come up except for the time-comparison bug above (this
bug was hidden by the time comparison bug :-D).
- Don't save tags for nonce values in the time-wait cache
since these are used only during cookie collisions and do
not matter if they are unique or not.
MFC after: 1 week

- fix sctp_ifn initial refcount issue (prevents deletion)
- fix a bug during cookie collision that prevented an
association from coming up in a specific restart case.
- Fix it so the shutdown-pending flag gets removed (this is
more for correctness then needed) when we enter shutdown-sent
or shutdown-ack-sent states.
- Fix a bug that caused the receiver to sometimes NOT send
a SACK when a duplicate TSN arrived. Without this fix
it was possible for the association to fall down if the
- Deleted primary destination is also stored when SCTP_MOBILITY_BASE.
(Previously, it is stored when only SCTP_MOBILITY_FASTHANDOFF)
- Fix a locking issue where we might call send_initiate_ack() and
incorrectly state the lock held/not held. Also fix it so that
when we release the lock the inp cannot be deleted on us.
- Add the debug option that can cause the stack to panic instead
of aborting an assoc. This does not and should never show up
in options but is useful for debugging unexpected aborts.
- Add cumack_log sent to track sending cumack information for
the debug case where we are running a special log per assoc.
- Added extra () aroudn sctp_sbspace macro to avoid compile warnings.
MFC after: 1 week

Spelling fix for interupt -> interrupt

- We should return error = 0 and the upper processing would
return a zero length read. Otherwise we don't return the
right error indication.

Approved by: re@freebsd.org (gnn)

- Bug fix managing congestion parameter on immediate
retransmittion by handover event (fast mobility code)
- Fixed problem of mobility code which is caused by remaining
parameters in the deleted primary destination.
- Add a missing lock. When a peer sends an INIT, and while we
are processing it to send an INIT-ACK the socket is closed,
we did not hold a lock to keep the socket from going away.
Add protection for this case.
- Fix so that arwnd is alway uses the minimal rwnd if the user
has set the socket buffer smaller. Found this when the test
org decided to see what happens when you set in a rwnd of 10
bytes (which is not allowed per RFC .. 4k is minimum).
- Fixes so a cookie-echo ootb will NOT cause an abort to
be sent. This was happening in a MPI collision case.
- Examined all panics and unless there was no recovery, moved
any that were not already to INVARANTS.

Approved by: re@freebsd.org (gnn)

- fix (global) address handling in the presence of duplicates, the
last interface should own the address, but the current code
fumbles the handoff. This fixes that.
- move address related debugs to PCB4 and add additional ones to
help in debugging address problems.

Approved by: re@freebsd.org (K Smith)

- The address lock is changed to a rwlock. This
also involves macro changes to have a RLOCK and a WLOCK
and placing the correct version within the code.
- The INP-INFO lock is changed to a rwlock.
- When sctp_shutdown() is called on Mac OS X, the socket lock is held.
So call sctp_chunk_output with SCTP_SO_LOCKED and
not SCTP_SO_NOT_LOCKED.
- Add SCTP_IPI_ADDR_[RW]LOCK and SCTP_IPI_ADDR_[RW]UNLOCK for Mac OS X.
- u_int64_t -> uint64_t
- add missing addr unlock for error return path
Approved by: re@freebsd.org (K Smith)

- DF bit was on for COOKIE-ECHO chunks. This is
incorrect and should be OFF letting IP fragment
large cookie-echos.
- Rename sysctl variable logging to log_level.
- Fix description of sysctl variable stats.
- Add sysctl variable log to make sctp_log readable via sysctl
mechanism (this is by compile switch and targets non KTR platforms or
when someone wants to do performance wise tracing).
- Removed debug code

Approved by: re@freebsd.org (B Mah)

- Incorrect error EAGAIN returned for invalid send on a locked
stream (using EEOR mode). Changed to EINVAL (in sctp_output.c)
- Static analysis comments added
- fix in mobility code to return a value (static analysis found).
- sctp6_notify function made visible instead of
static (this is needed for Panda).

Approved by: re@freebsd.org (B Mah)

- send call has a reference to uio->uio_resid in
the recent send code, but uio may be NULL on sendfile
calls. Change to use sndlen variable.
- EMSGSIZE is not being returned in non-blocking mode
and needs a small tweak to look if the msg would
ever fit when returning EWOULDBLOCK.
- FWD-TSN has a bug in stream processing which could
cause a panic. This is a follow on to the codenomicon
fix.
- PDAPI level 1 and 2 do not work unless the reader
gets his returned buffer full. Fix so we can break
out when at level 1 or 2.
- Fix fast-handoff features to copy across properly on
accepted sockets
- Fix sctp_peeloff() system call when no true system call
exists to screen arguments for errors. In cases where a
real system call exists the system call itself does this.
- Fix raddr leak in recent add-ip code change for bundled
asconfs (even when non-bundled asconfs are received)
- Make sure ipi_addr lock is held when walking global addr
list. Need to change this lock type to a rwlock().
- Add don't wake flag on both input and output when the
socket is closing.
- When deleting an address verify the interface is correct
before allowing the delete to process. This protects panda
and unnumbered.
- Clean up old sysctl stuff and get rid of the old Open/Net
BSD structures.
- Add a function to watch the ranges in the sysctl sets.
- When appending in the reassembly queue, validate that
the assoc has not gone to about to be freed. If so
(in the middle) abort out. Note this especially effects
MAC I think due to the lock/unlock they do (or with
LOCK testing in place).
- Netstat patch to get rid of warnings.
- Make sure that no data gets queued to inactive/unconfirmed
destinations. This especially effect CMT but also makes a
impact on regular SCTP as well.
- During init collision when we detect seq number out
of sync we need to treat it like Case C and discard
the cookie (no invarient needed here).
- Atomic access to the random store.
- When we declare a vtag good, we need to shove it
into the time wait hash to prevent further use. When
the tag is put into the assoc hash, we need to remove it
from the twait hash (where it will surely be). This prevents
duplicate tag assignments.
- Move decr-ref count to better protect sysctl out of
data.
- ltrace error corrections in sctp6_usrreq.c
- Add hook for interface up/down to be sent to us.
- Make sysctl() exported structures independent of processor
architecture.
- Fix route and src addr cache clearing for delete address case.
- Make sure address marked SCTP_DEL_IP_ADDRESS is never selected
as src addr.
- in icmp handling fixed so we actually look at the icmp codes
to figure out what to do.
- Modified mobility code.
Reception of DELETE IP ADDRESS for a primary destination and
SET PRIMARY for a new primary destination is used for
retransmission trigger to the new primary destination.
Also, in this case, destination of chunks in send_queue are
changed to the new primary destination.
- Fix so that we disallow sending by mbuf to ever have EEOR
mode set upon it.

Approved by: re@freebsd.org (B Mah)

- Locking compatiability changes. This involves adding
additional flags to many function calls. The flags only
get used in BSD when we compile with lock testing. These
flags allow apple to escape the "giant" lock it holds on
the socket and have more fine-grained locking in the NKE.
It also allows us to test (with witness) the locking used
by apple via a compile switch (manually applied).

Approved by: re@freebsd.org(B Mah)

- During shutdown pending, when the last sack came in and
the last message on the send stream was "null" but still
there, a state we allow, we could get hung and not clean
it up and wait for the shutdown guard timer to clear the
association without a graceful close. Fix this so that
that we properly clean up.
- Added support for Multiple ASCONF per new RFC. We only
(so far) accept input of these and cannot yet generate
a multi-asconf.
- Sysctl'd support for experimental Fast Handover feature. Always
disabled unless sysctl or socket option changes to enable.
- Error case in add-ip where the peer supports AUTH and ADD-IP
but does NOT require AUTH of ASCONF/ASCONF-ACK. We need to
ABORT in this case.
- According to the Kyoto summit of socket api developers
(Solaris, Linux, BSD). We need to have:
o non-eeor mode messages be atomic - Fixed
o Allow implicit setup of an assoc in 1-2-1 model if
using the sctp_**() send calls - Fixed
o Get rid of HAVE_XXX declarations - Done
o add a sctp_pr_policy in hole in sndrcvinfo structure - Done
o add a PR_SCTP_POLICY_VALID type flag - yet to-do in a future patch!
- Optimize sctp6 calls to reuse code in sctp_usrreq. Also optimize
when we close sending out the data and disabling Nagle.
- Change key concatenation order to match the auth RFC
- When sending OOTB shutdown_complete always do csum.
- Don't send PKT-DROP to a PKT-DROP
- For abort chunks just always checksums same for
shutdown-complete.
- inpcb_free front state had a bug where in queue
data could wedge an assoc. We need to just abandon
ones in front states (free_assoc).
- If a peer sends us a 64k abort, we would try to
assemble a response packet which may be larger than
64k. This then would be dropped by IP. Instead make
a "minimum" size for us 64k-2k (we want at least
2k for our initack). If we receive such an init
discard it early without all the processing.
- When we peel off we must increment the tcb ref count
to keep it from being freed from underneath us.
- handling fwd-tsn had bugs that caused memory overwrites
when given faulty data, fixed so can't happen and we
also stop at the first bad stream no.
- Fixed so comm-up generates the adaption indication.
- peeloff did not get the hmac params copied.
- fix it so we lock the addr list when doing src-addr selection
(in future we need to use a multi-reader/one writer lock here)
- During lowlevel output, we could end up with a _l_addr set
to null if the iterator is calling the output routine. This
means we would possibly crash when we gather the MTU info.
Fix so we only do the gather where we have a src address
cached.
- we need to be sure to set abort flag on conn state when
we receive an abort.
- peeloff could leak a socket. Moved code so the close will
find the socket if the peeloff fails (uipc_syscalls.c)

Approved by: re@freebsd.org(Ken Smith)

- Fix address add handling to clear cached routes and source addresses
when peer acks the add in case the routing table changes.
- Fix sctp_lower_sosend to send shutdown chunk for mbuf send
case when sndlen = 0 and sinfoflag = SCTP_EOF
- Fix sctp_lower_sosend for SCTP_ABORT mbuf send case with null data,
So that it does not send the "null" data mbuf out and cause
it to get freed twice.
- Fix so auto-asconf sysctl actually effect the socket's asconf state.
- Do not allow SCTP_AUTO_ASCONF option to be used on subset bound sockets.
- Memset bug in sctp_output.c (arguments were reversed) submitted
found and reported by Dave Jones (davej@codemonkey.org.uk).
- PD-API point needs to be invoked >= not just > to conform to socket api
draft this fixes sctp_indata.c in the two places need to be >=.
- move M_NOTIFICATION to use M_PROTO5.
- PEER_ADDR_PARAMS did not fail properly if you specify an address
that is not in the association with a valid assoc_id. This meant
you got or set the stcb level values instead of the destination
you thought you were going to get/set. Now validate if the
stcb is non-null and the net is NULL that the sa_family is
set and the address is unspecified otherwise return an error.
- The thread based iterator could crash if associations were freed
at the exact time it was running. rework the worker thread to
use the increment/decrement to prevent this and no longer use
the markers that the timer based iterator uses.
- Fix the memleak in sctp_add_addr_to_vrf() for the case when it is
detected that ifa is already pointing to a ifn.
- Fix it so that if someone is so insane that they drop the
send window below the minimal add mark, they still can send.
- Changed all state for associations to use mask safe macro.
- During front states in association freeing in sctp_inpcbfree, we
had a locking problem where locks were not in place where they
should have been.
- Free association calls were not testing the return value in
sctp_inpcb_free() properly... others should be cast void returns
where we don't care about the return value.
- If a reference count is held on an assoc, even from the "force free"
we should not do the actual free.. but instead let the timer
free it.
- When we enter sctp_input(), if the SCTP_ASOC_ABOUT_TO_BE_FREED
flag is set, we must NOT process the packet but handle it like
ootb. This is because while freeing an assoc we release the
locks to get all the higher order locks so we can purge all
the hash tables. This leaves a hole if a packet comes in
just at that point. Now sctp_common_input_processing() will
call the ootb code in such a case.
- Change MBUF M_NOTIFICATION to use M_PROTO5 (per Sam L). This makes
it so we don't have a conflict (I think this is a covertity change).
We made this change AFTER some conversation and looking to make sure
that M_PROTO5 does not have a problem between SCTP and the 802.11
stuff (which is the only other place its used).
- Fixed lock order reversal and missing atomic protection around
locked_tcb during association lookup and the 1-2-1 model.
- Added debug to source address selection.
- V6 output must always do checksum even for loopback.
- Remove more locks around inp that are not needed for an atomically
added/subtracted ref count.
- slight optimization in the way we zero the array in sctp_sack_check()
- It was possible to respond to a ABORT() with bad checksum with
a PKT-DROP. This lead to a PKT-DROP/ABORT war. Add code to NOT
send a PKT-DROP to any ABORT().
- Add an option for local logging (useful for macintosh or when
you need better performing during debugging). Note no commands
are here to get the log info, you must just use kgdb.
- The timer code needs to be aware of if it needs to call
sctp_sack_check() to slide the maps and adjust the cum-ack.
This is because it may be out of sync cum-ack wise.
- Added threshold managment logging.
- If the user picked just the right size, that just filled the send
window minus one mtu, we would enter a forever loop not copying and
at the same time not blocking. Change from < to <= solves this.
- Sysctl added to control the fragment interleave level which defaults
to 1.
- My rwnd control was not being used to control the rwnd properly (we
did not add and subtract to it :-() this is now fixed so we handle
small messages (1 byte etc) better to bring our rwnd down more
slowly.

Approved by: re@freebsd.org (Bruce Mah)

- Remove extra comment for 7.0 (no GIANT here).
- Remove unneeded WLOCK/UNLOCK of inp for getting TCB lock.
- Fix panic that may occur when freeing an assoc that has partial
delivery in progress (may dereference null socket pointer when
queuing partial delivery aborted notification)
- Some spacing and comment fixes.
- Fix address add handling to clear cached routes and source addresses
when peer acks the add in case the routing table changes.
Approved by: re@freebsd.org (Bruce Mah)

- change number assignments for SHA225-512 (match artisync
for bakeoff.. using the next sequential ones)
- In cookie processing 1-2-1, we did not increment the stcb
refcnt before releasing the tcb lock. We need to do this
to keep the tcb from being freed by a abort or ?? unlikely
but worth doing. Also get rid of unneed INP_WLOCK.
- extra receive info included the rcvinfo which killed the
padding/alignment. We now redefine all the fields properly
so they both align properly both to 128 bytes.
- A peeled off socket would not close without an error due to
its misguided idea that sctp_disconnect() was not supported
on it. This fixes it so it goes through the proper path.
- When an assoc was being deleted after abort (via a timer) a
small race condition exists where we might take a packet for
the old assoc (since we are waiting for a cleanup timer). This
state especially happens in mac. We now add a state in the asoc
so these can properly handle the packet as OOTB.
Approved by: re@freebsd.org(Ken Smith)

- take out a needless panic under invariants for sctp_output.c
- Fix addrs's error checking of sctp_sendx(3) when addrcnt is less than
SCTP_SMALL_IOVEC_SIZE
- re-add back inpcb_bind local address check bypass capability
- Fix it so sctp_opt_info is independant of assoc_id postion.
- Fix cookie life set to use MSEC_TO_TICKS() macro.
- asconf changes
o More comment changes/clarifications related to the old local address
"not" list which is now an explicit restricted list.

o Rename some functions for clarity:
- sctp_add/del_local_addr_assoc to xxx_local_addr_restricted()
- asconf related iterator functions to sctp_asconf_iterator_xxx()

o Fix bug when the same address is deleted and added (and removed from
the asconf queue) where the ifa is "freed" twice refcount wise,
possibly freeing it completely.

o Fix bug in output where the first ASCONF would not go out after the
last address is changed (e.g. only goes out when retransmitted).

o Fix bug where multiple ASCONFs can be bundled in the same packet with
the and with the same serial numbers.

o Fix asconf stcb iterator to not send ASCONF until after all work
queue entries have been processed.

o Change behavior so that when the last address is deleted (auto asconf
on a bound all endpoint) no action is taken until an address is
added; at that time, an ASCONF add+delete is sent (if the assoc
is still up).

o Fix local address counting so that address scoping is taken into
account.

o #ifdef SCTP_TIMER_BASED_ASCONF the old timer triggered sending
of ASCONF (after an RTO). The default now is to send
ASCONF immediately (except for the case of changing/deleting the
last usable address).
Approved by: re(ken smith)@freebsd.org

- added pre-checks to the bindx call.
- use proper tick gathering macro instead of ticks directly.
- Placed reasonable boundaries on sets that a user can do
that are converted to ticks from ms.
- Fix CMT_PF to always check to be sure CMT is on.
- Fix ticks use of CMT_PF.
- put back code to allow asconfs to be queued while INITs are in flight
and before the assoc is established.
- During window probes, an ack'd packet might be left with the window
probe mark on it causing it to be retransmitted. Change so that
the flight decrease macro clears the window_probe mark.
- Additional logging flight size/reading and ASOC LOG. This
is only enabled if you manually insert things into opt_sctp.h
since its a set of debug code only.
- Found an interesting SMP race in the way data was appended which
could cause a reader to lose a part of a message, had to
reorder when we marked the message was complete to after
the data was appended.
- bug in ADD-IP for the subset bound socket case when the peer has only
one address
- fix ASCONF implicit success/error handling case
- proper support of jails in Freebsd 6>
- copy out the timeval for the 64 bit sparc world on cookie-echo
alignment error crashes without this).
Approved by: re(Ken Smith)

- Modular congestion control, with RFC2581 being the default.
- CMT_PF states added (w/sysctl to turn the PF version on)
- sctp_input.c had a missing incr of cookie case when the
auth was bad. This meant a free was called without an
increment to refcnt, added increment like rest of code.
- There was a case, unlikely, when the scope of the destination
changed (this is a TSNH case). In that case, it would not free
the alloc'ed asoc (in sctp_input.c).
- When listed addresses found a colliding cookie/Init, then
the collided upon tcb was not unlocked in sctp_pcb.c
- Add error checking on arguments of sctp_sendx(3) to prevent it from
referencing a NULL pointer.
- Fix an error return of sctp_sendx(3), it was returing
ENOMEM not -1.
- Get assoc id was changed to use the sanctified socket api
method for getting a assoc id (PEER_ADDR_INFO instead of
PEER_ADDR_PARAMS).
- Fix it so a peeled off socket will get a proper error return
if it trys to send to a different address then it is connected to.
- Fix so that select_a_stream can avoid an endless loop that
could hang a caller.
- time_entered (state set time) was not being set in all cases
to the time we went established.
Approved by: re(ken smith)

- Consolidate the code that free's chunks to actually also
call the sctp_free_remote_address() function.
- Assure that when we allocate a chunk the whoTo is NULL,
also when we free it and place it into the cache we NULL
it (that way the consolidation code will always work).
- Fix a small race, when a empty data holder is left on the stream
out queue, and both sides do a shutdown, the empty data holder
would prevent us from sending a SHUTDOWN-ACK and at the same time we
never would cleanup the empty holder (since nothing was ever in queue).
We now add a utility function that a) cleans up empty holders and
b) properly determines if there are still pending data chunks on
the stream out wheel.
Approved by: re@freebsd.org (Ken Smith)

- Update bindx address checking to properly screen out address
per the socket api, adding port validation. We allow port 0
or the already bound port number and no others.

Approved by: re@freebsd.org (Ken Smith)