MFC r295549:
Loopback addresses are 127.0.0.0/8, not 127.0.0.1/32.

MFC r295668:
Improve the teardown of the SCTP stack.

MFC r295670:
Whitespace changes.

MFC r295708:
Address a warning reported by D5245 / PVS.

MFC r295709:
Code cleanup which will silence a warning in PVS / D5245.

MFC r295710:
Add protection code for issues reported by PVS / D5245.

MFC r295771:
Fix reporting of mapped addressed in getpeername() and getsockname() for
IPv6 SCTP sockets.
This bugs were found because of an issue reported by PVS / D5245.

MFC r295772:
Add some protection code.

MFC r295773:
Add protection code.

MFC r295805:
Use the SCTP level pointer, not the interface level.

MFC r295929:
Don't leak an address in an error path.

Approved by: re (marius)

MFC r294995:
Always look in the TCP pool.
This fixes issues with a restarting peer when the listening
1-to-1 style socket is closed.

MFC r295021:
Remove debug output which was committed by accident.
Thanks to Oliver Pinter for reporting.

MFC r295069:
Ignore peer addresses in a consistent way also when checking for
new addresses during restart. If this is not done, restart doesn't
work when the local socket is IPv4 only and the peer uses
IPv4 and IPv6 addresses.

MFC r295070:
Don't change the remote UDP encapsulation port for SCTP packets
containing an INIT chunk.

MFC r295072:
Don't allow a remote encapsulation port change during the
SCTP restart procedure.

MFC r295075:
Update the path mtu when turning on/off UDP encapsulation for SCTP.

MFC r295077:
Add missing parentheses. This was reported by ccaughie via GitHub
for the userland stack.

Approved by: re (kib)

MFC r294057:
Fix a bug in INIT handling on accepted 1-to-1 style sockets when the
listener is closed.
This fix allows the following packetdrill test to pass:
// Setup a connected, blocking 1-to-1 style socket
+0.0 socket(..., SOCK_STREAM, IPPROTO_SCTP) = 3
// Check the handshake with en empty(!) cookie
+0.0 bind(3, ..., ...) = 0
+0.0 listen(3, 1) = 0
+0.0 < sctp: INIT[flgs=0, tag=1, a_rwnd=1500, os=1, is=1, tsn=1]
+0.0 > sctp: INIT_ACK[flgs=0, tag=2, a_rwnd=..., os=..., is=..., tsn=1, ...]
+0.0 < sctp: COOKIE_ECHO[flgs=0, len=..., val=...]
+0.0 > sctp: COOKIE_ACK[flgs=0]
+0.0 accept(3, ..., ...) = 4
+0.0 close(3) = 0
// Inject an INIT chunk and expect an INIT-ACK
+0.0 < sctp: INIT[flgs=0, tag=3, a_rwnd=1500, os=1, is=1, tsn=1]
+0.0 > sctp: INIT_ACK[flgs=0, tag=..., a_rwnd=..., os=..., is=..., tsn=..., ...]

MFC r291904:
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 r291141:
Fix the handling of IPSec policies in the SCTP stack. At least
make sure they are not leaked...

MFC r291140:
Revert part of r291137 which seems correct, bit does not fix the
resource problem I'm currently hunting down.

MFC r291137:
Don't send SHUTDOWN chunk when the association is in a front state
and the applications calls shutdown(..., SHUT_WR) or
shutdown(..., SHUT_RDWR).

MFC r289570:
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 r285925:
Provide consistent error causes whenever an ABORT chunk is sent.

MFC r284515:
Add FIB support for SCTP.
This fixes https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=200379

PR: 200379

MFC r283664:

Retire SCTP_DONT_DO_PRIVADDR_SCOPE which was never defined.

MFC r283650:

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

MFC r280459:

Fix two bugs which resulted in a screwed up end point list:
* Use a save way to walk throught a list while manipulting it.
* Have to appropiate locks in place.
Joint work with rrs@

MFC r279859:

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

MFC r277031

Remove dead code.

Reported by: Coverity
CID: 748665

MFC r277030:

Remove dead code.

Reported by: Coverity
CID: 748666

MFC r275869:

Add a missing break.

Reported by: Coverity
CID: 1232014

MFC r275358 r275483 r276982 - Removing M_FLOWID by hps@

r275358:
Start process of removing the use of the deprecated "M_FLOWID" flag
from the FreeBSD network code. The flag is still kept around in the
"sys/mbuf.h" header file, but does no longer have any users. Instead
the "m_pkthdr.rsstype" field in the mbuf structure is now used to
decide the meaning of the "m_pkthdr.flowid" field. To modify the
"m_pkthdr.rsstype" field please use the existing "M_HASHTYPE_XXX"
macros as defined in the "sys/mbuf.h" header file.

This patch introduces new behaviour in the transmit direction.
Previously network drivers checked if "M_FLOWID" was set in "m_flags"
before using the "m_pkthdr.flowid" field. This check has now now been
replaced by checking if "M_HASHTYPE_GET(m)" is different from
"M_HASHTYPE_NONE". In the future more hashtypes will be added, for
example hashtypes for hardware dedicated flows.

"M_HASHTYPE_OPAQUE" indicates that the "m_pkthdr.flowid" value is
valid and has no particular type. This change removes the need for an
"if" statement in TCP transmit code checking for the presence of a
valid flowid value. The "if" statement mentioned above is now a direct
variable assignment which is then later checked by the respective
network drivers like before.

r275483:
Remove M_FLOWID from SCTP code.

r276982:
Remove no longer used "M_FLOWID" flag from mbuf.h and update the netisr
manpage.

Note: The FreeBSD version has been bumped.

Reviewed by: hps, tuexen
Sponsored by: Limelight Networks

MFC r271643:
Chunk IDs are 8 bit entities, not 16 bit.
Thanks to Peter Kasting from Google for drawing
my attention to it.

MFC r271665:
The MTU is handled as a 32-bit entity within the SCTP stack.
This was reported by Peter Kasting from Google.

MFC r271670:
Make a type conversion explicit. When compiling this code on
Windows as part of the SCTP userland stack, this fixes a
warning reported by Peter Kasting from Google.

MFC r271672:
Small cleanup which addresses a warning regaring the truncation
of a 64-bit entity to a 32-bit entity. This issue was reported by
Peter Kasting from Google.

MFC r271673:
Use a consistent type for the number of HMAC algorithms.
This fixes a bug which resulted in a warning on the userland
stack, when compiled on Windows.
Thanks to Peter Kasting from Google for reporting the issue and
provinding a potential fix.

MFC r271674:
Add a explict cast to silence a warning when building
the userland stack on Windows.
This issue was reported by Peter Kasting from Google.

Approved by: re (kib)

MFC r270673:
Announce SCTP support in the kern.features sysctl variables.

MFC r270859:
Enable SCTP support. It runs perfectly fine on a Wandboard quad.

MFC r271204 with manual intervention:
Fix the handling of sysctl variables when used with VIMAGE.
While there do some cleanup of the code.

MFC r271209:
Fix a leak of an address, if the address is scheduled for removal
and the stack is torn down.
Thanks to Peter Bostroem and Jiayang Liu from Google for reporting the
issue.

MFC r271219:
Use SYSCTL_PROC instead of SYSCTL_VNET_PROC.
Suggested by: glebius@

MFC r271221:
Use union sctp_sockstore instead of struct sockaddr_storage. This
eliminates 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 r271228:
Address another warnings reported by Patrick Laimbock when compiling
in userspace. While there, improve consistency.

MFC r271230:
Address warnings generated by the clang analyzer.

Approved by: re (kib)

MFC r269858:

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

MFC r269527:

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

MFC r269481:

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 r269475:

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 r269448:

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 r269436, r269445:

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.

MFC r269396:

Remove the asconf_auth_nochk sysctl. This was off by default and only
existed to be able to test with non-compliant peers a long time ago.

MFC r268534:

Bugfix: When a remote address was added to an endpoint,
a source address was selected and cached, but it was not
stored that is was cached. This resulted in selecting
different source addresses for the INIT-ACK and COOKIE-ACK
when possible.
Thanks to Niu Zhixiong for reporting the issue.

MFC r268526:

Integrate upstream changes.

MFC r267674:

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 r265455:

Remove unused code. This is triggered by the bugreport of Sylvestre Ledru
which deal with useless code in the user land stack:
https://bugzilla.mozilla.org/show_bug.cgi?id=1003929

MFC r263922:

Handle an edge case of address management similar to TCP.
This needs to be reconsidered when the address handling
will be reimplemented.
The patch is from rrs@.

MFC r263237:

* 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 r258574:

Only initialize some mutexes for the default VNET.

In r208160, sctp_it_ctl was made a global variable, across all VNETs.
However, sctp_init() is called for every VNET that is created. This results
in the same global mutexes which are part of sctp_it_ctl being initialized. This can result
in crashes if many jails are created.

To reproduce the problem:
(1) Take a GENERIC kernel config, and add options for: VIMAGE, WITNESS,
INVARIANTS.
(2) Run this command in a loop:
jail -l -u root -c path=/ name=foo persist vnet && jexec foo ifconfig lo0 127.0.0.1/8 && jail -r foo

(see http://lists.freebsd.org/pipermail/freebsd-current/2010-November/021280.html )

Witness will warn about the same mutex being initialized.

Fix the problem by only initializing these mutexes in the default VNET.

MFC r258765:

In
http://svnweb.freebsd.org/changeset/base/258221
I introduced a bug which initialized global locks
whenever the SCTP stack initialized. This was fixed in
http://svnweb.freebsd.org/changeset/base/258574
by rodrigc@. He just initialized the locks for
the default vnet. This fix reverts to the old
behaviour before r258221, which explicitly makes
sure it is only called once, because this works also on
other platforms.

Approved by: re@ (gjb)

MFC r256556:
Remove a buggy comparision when setting manually the path MTU.
After fixing, the comparision would have become redundant.
Thanks to Andrew Galante for reporting the issue.

MFC r257272:
Fix compilation if SCTP_DONT_DO_PRIVADDR_SCOPE is defined.
The issue was reported by Andrew Galante.

MFC r257274:
Fix the value of *optlen when calling getsockopt() for
SCTP_REMOTE_UDP_ENCAPS_PORT.
This issue was reported by Andrew Galante.

MFC r257359:
Terminate a debug output with a \n.

MFC r257555:
Changes from upstream to improve compilation when INET or INET6
or none of them is defined.

MFC r257574:
Unlock the lock before destroying it.
This issue was reported by Andrew Galante.

MFC r257800:
Use htons()/ntohs() appropriately.
These issues were reported by Andrew Galante.

MFC r257803:
Make sure that we don't try to build an ASCONF-ACK chunk
larger than what fits in the the mbuf cluster.
This issue was reported by Andrew Galante.

MFC r257804:
Get rid of the artification limitation enforced by
SCTP_AUTH_RANDOM_SIZE_MAX.
This was suggested by Andrew Galante.

MFC r258221:
Cleanups which result in fixes which have been made upstream
and where partially suggested by Andrew Galante.
There is no functional change in FreeBSD.

MFC r258224:
When determining if an address belongs to an stcb, take the address family
into account for wildcard bound endpoints.

MFC r258228:
Remove a stray write operation.

MFC r258235:
Use SCTP_PR_SCTP_TTL when the user provides a positive
timetolive in sctp_sendmsg().

Approved by: re@

MFC r284515:
Add FIB support for SCTP.
This fixes https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=200379

PR: 200379

MFC r283664:

Retire SCTP_DONT_DO_PRIVADDR_SCOPE which was never defined.

MFC r283650:

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

MFC r280459:

Fix two bugs which resulted in a screwed up end point list:
* Use a save way to walk throught a list while manipulting it.
* Have to appropiate locks in place.
Joint work with rrs@

MFC r279859:

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

MFC r277031

Remove dead code.

Reported by: Coverity
CID: 748665

MFC r277030:

Remove dead code.

Reported by: Coverity
CID: 748666

MFC r275869:

Add a missing break.

Reported by: Coverity
CID: 1232014

MFC r275358 r275483 r276982 - Removing M_FLOWID by hps@

r275358:
Start process of removing the use of the deprecated "M_FLOWID" flag
from the FreeBSD network code. The flag is still kept around in the
"sys/mbuf.h" header file, but does no longer have any users. Instead
the "m_pkthdr.rsstype" field in the mbuf structure is now used to
decide the meaning of the "m_pkthdr.flowid" field. To modify the
"m_pkthdr.rsstype" field please use the existing "M_HASHTYPE_XXX"
macros as defined in the "sys/mbuf.h" header file.

This patch introduces new behaviour in the transmit direction.
Previously network drivers checked if "M_FLOWID" was set in "m_flags"
before using the "m_pkthdr.flowid" field. This check has now now been
replaced by checking if "M_HASHTYPE_GET(m)" is different from
"M_HASHTYPE_NONE". In the future more hashtypes will be added, for
example hashtypes for hardware dedicated flows.

"M_HASHTYPE_OPAQUE" indicates that the "m_pkthdr.flowid" value is
valid and has no particular type. This change removes the need for an
"if" statement in TCP transmit code checking for the presence of a
valid flowid value. The "if" statement mentioned above is now a direct
variable assignment which is then later checked by the respective
network drivers like before.

r275483:
Remove M_FLOWID from SCTP code.

r276982:
Remove no longer used "M_FLOWID" flag from mbuf.h and update the netisr
manpage.

Note: The FreeBSD version has been bumped.

Reviewed by: hps, tuexen
Sponsored by: Limelight Networks

MFC r271643:
Chunk IDs are 8 bit entities, not 16 bit.
Thanks to Peter Kasting from Google for drawing
my attention to it.

MFC r271665:
The MTU is handled as a 32-bit entity within the SCTP stack.
This was reported by Peter Kasting from Google.

MFC r271670:
Make a type conversion explicit. When compiling this code on
Windows as part of the SCTP userland stack, this fixes a
warning reported by Peter Kasting from Google.

MFC r271672:
Small cleanup which addresses a warning regaring the truncation
of a 64-bit entity to a 32-bit entity. This issue was reported by
Peter Kasting from Google.

MFC r271673:
Use a consistent type for the number of HMAC algorithms.
This fixes a bug which resulted in a warning on the userland
stack, when compiled on Windows.
Thanks to Peter Kasting from Google for reporting the issue and
provinding a potential fix.

MFC r271674:
Add a explict cast to silence a warning when building
the userland stack on Windows.
This issue was reported by Peter Kasting from Google.

Approved by: re (kib)

MFC r270673:
Announce SCTP support in the kern.features sysctl variables.

MFC r270859:
Enable SCTP support. It runs perfectly fine on a Wandboard quad.

MFC r271204 with manual intervention:
Fix the handling of sysctl variables when used with VIMAGE.
While there do some cleanup of the code.

MFC r271209:
Fix a leak of an address, if the address is scheduled for removal
and the stack is torn down.
Thanks to Peter Bostroem and Jiayang Liu from Google for reporting the
issue.

MFC r271219:
Use SYSCTL_PROC instead of SYSCTL_VNET_PROC.
Suggested by: glebius@

MFC r271221:
Use union sctp_sockstore instead of struct sockaddr_storage. This
eliminates 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 r271228:
Address another warnings reported by Patrick Laimbock when compiling
in userspace. While there, improve consistency.

MFC r271230:
Address warnings generated by the clang analyzer.

Approved by: re (kib)

MFC r269858:

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

MFC r269527:

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

MFC r269481:

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 r269475:

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 r269448:

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 r269436, r269445:

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.

MFC r269396:

Remove the asconf_auth_nochk sysctl. This was off by default and only
existed to be able to test with non-compliant peers a long time ago.

MFC r268534:

Bugfix: When a remote address was added to an endpoint,
a source address was selected and cached, but it was not
stored that is was cached. This resulted in selecting
different source addresses for the INIT-ACK and COOKIE-ACK
when possible.
Thanks to Niu Zhixiong for reporting the issue.

MFC r268526:

Integrate upstream changes.

MFC r267674:

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 r265455:

Remove unused code. This is triggered by the bugreport of Sylvestre Ledru
which deal with useless code in the user land stack:
https://bugzilla.mozilla.org/show_bug.cgi?id=1003929

MFC r263922:

Handle an edge case of address management similar to TCP.
This needs to be reconsidered when the address handling
will be reimplemented.
The patch is from rrs@.

MFC r263237:

* 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 r258574:

Only initialize some mutexes for the default VNET.

In r208160, sctp_it_ctl was made a global variable, across all VNETs.
However, sctp_init() is called for every VNET that is created. This results
in the same global mutexes which are part of sctp_it_ctl being initialized. This can result
in crashes if many jails are created.

To reproduce the problem:
(1) Take a GENERIC kernel config, and add options for: VIMAGE, WITNESS,
INVARIANTS.
(2) Run this command in a loop:
jail -l -u root -c path=/ name=foo persist vnet && jexec foo ifconfig lo0 127.0.0.1/8 && jail -r foo

(see http://lists.freebsd.org/pipermail/freebsd-current/2010-November/021280.html )

Witness will warn about the same mutex being initialized.

Fix the problem by only initializing these mutexes in the default VNET.

MFC r258765:

In
http://svnweb.freebsd.org/changeset/base/258221
I introduced a bug which initialized global locks
whenever the SCTP stack initialized. This was fixed in
http://svnweb.freebsd.org/changeset/base/258574
by rodrigc@. He just initialized the locks for
the default vnet. This fix reverts to the old
behaviour before r258221, which explicitly makes
sure it is only called once, because this works also on
other platforms.

Approved by: re@ (gjb)

MFC r256556:
Remove a buggy comparision when setting manually the path MTU.
After fixing, the comparision would have become redundant.
Thanks to Andrew Galante for reporting the issue.

MFC r257272:
Fix compilation if SCTP_DONT_DO_PRIVADDR_SCOPE is defined.
The issue was reported by Andrew Galante.

MFC r257274:
Fix the value of *optlen when calling getsockopt() for
SCTP_REMOTE_UDP_ENCAPS_PORT.
This issue was reported by Andrew Galante.

MFC r257359:
Terminate a debug output with a \n.

MFC r257555:
Changes from upstream to improve compilation when INET or INET6
or none of them is defined.

MFC r257574:
Unlock the lock before destroying it.
This issue was reported by Andrew Galante.

MFC r257800:
Use htons()/ntohs() appropriately.
These issues were reported by Andrew Galante.

MFC r257803:
Make sure that we don't try to build an ASCONF-ACK chunk
larger than what fits in the the mbuf cluster.
This issue was reported by Andrew Galante.

MFC r257804:
Get rid of the artification limitation enforced by
SCTP_AUTH_RANDOM_SIZE_MAX.
This was suggested by Andrew Galante.

MFC r258221:
Cleanups which result in fixes which have been made upstream
and where partially suggested by Andrew Galante.
There is no functional change in FreeBSD.

MFC r258224:
When determining if an address belongs to an stcb, take the address family
into account for wildcard bound endpoints.

MFC r258228:
Remove a stray write operation.

MFC r258235:
Use SCTP_PR_SCTP_TTL when the user provides a positive
timetolive in sctp_sendmsg().

Approved by: re@