Commit Graph

107 Commits

Author SHA1 Message Date
Robert Watson
78b5071407 Update stats in struct tcpstat using two new macros, TCPSTAT_ADD() and
TCPSTAT_INC(), rather than directly manipulating the fields across the
kernel.  This will make it easier to change the implementation of
these statistics, such as using per-CPU versions of the data structures.

MFC after:	3 days
2009-04-11 22:07:19 +00:00
Robert Watson
ad71fe3c35 Correct a number of evolved problems with inp_vflag and inp_flags:
certain flags that should have been in inp_flags ended up in inp_vflag,
meaning that they were inconsistently locked, and in one case,
interpreted.  Move the following flags from inp_vflag to gaps in the
inp_flags space (and clean up the inp_flags constants to make gaps
more obvious to future takers):

  INP_TIMEWAIT
  INP_SOCKREF
  INP_ONESBCAST
  INP_DROPPED

Some aspects of this change have no effect on kernel ABI at all, as these
are UDP/TCP/IP-internal uses; however, netstat and sockstat detect
INP_TIMEWAIT when listing TCP sockets, so any MFC will need to take this
into account.

MFC after:      1 week (or after dependencies are MFC'd)
Reviewed by:    bz
2009-03-15 09:58:31 +00:00
Lawrence Stewart
24cb0f2232 Add TCP Appropriate Byte Counting (RFC 3465) support to kernel.
The new behaviour is on by default, and can be disabled by setting the
net.inet.tcp.rfc3465 sysctl to 0 to obtain previous behaviour.

The patch changes struct tcpcb in sys/netinet/tcp_var.h which breaks
the ABI. Bump __FreeBSD_version to 800061 accordingly. User space tools
that rely on the size of struct tcpcb (e.g. sockstat) need to be recompiled.

Reviewed by:	rpaulo, gnn
Approved by:	gnn, kmacy (mentors)
Sponsored by:	FreeBSD Foundation
2009-01-15 06:44:22 +00:00
Bjoern A. Zeeb
4b79449e2f Rather than using hidden includes (with cicular dependencies),
directly include only the header files needed. This reduces the
unneeded spamming of various headers into lots of files.

For now, this leaves us with very few modules including vnet.h
and thus needing to depend on opt_route.h.

Reviewed by:	brooks, gnn, des, zec, imp
Sponsored by:	The FreeBSD Foundation
2008-12-02 21:37:28 +00:00
Marko Zec
8b615593fc Step 1.5 of importing the network stack virtualization infrastructure
from the vimage project, as per plan established at devsummit 08/08:
http://wiki.freebsd.org/Image/Notes200808DevSummit

Introduce INIT_VNET_*() initializer macros, VNET_FOREACH() iterator
macros, and CURVNET_SET() context setting macros, all currently
resolving to NOPs.

Prepare for virtualization of selected SYSCTL objects by introducing a
family of SYSCTL_V_*() macros, currently resolving to their global
counterparts, i.e. SYSCTL_V_INT() == SYSCTL_INT().

Move selected #defines from sys/sys/vimage.h to newly introduced header
files specific to virtualized subsystems (sys/net/vnet.h,
sys/netinet/vinet.h etc.).

All the changes are verified to have zero functional impact at this
point in time by doing MD5 comparision between pre- and post-change
object files(*).

(*) netipsec/keysock.c did not validate depending on compile time options.

Implemented by:	julian, bz, brooks, zec
Reviewed by:	julian, bz, brooks, kris, rwatson, ...
Approved by:	julian (mentor)
Obtained from:	//depot/projects/vimage-commit2/...
X-MFC after:	never
Sponsored by:	NLnet Foundation, The FreeBSD Foundation
2008-10-02 15:37:58 +00:00
Bjoern A. Zeeb
603724d3ab Commit step 1 of the vimage project, (network stack)
virtualization work done by Marko Zec (zec@).

This is the first in a series of commits over the course
of the next few weeks.

Mark all uses of global variables to be virtualized
with a V_ prefix.
Use macros to map them back to their global names for
now, so this is a NOP change only.

We hope to have caught at least 85-90% of what is needed
so we do not invalidate a lot of outstanding patches again.

Obtained from:	//depot/projects/vimage-commit2/...
Reviewed by:	brooks, des, ed, mav, julian,
		jamie, kris, rwatson, zec, ...
		(various people I forgot, different versions)
		md5 (with a bit of help)
Sponsored by:	NLnet Foundation, The FreeBSD Foundation
X-MFC after:	never
V_Commit_Message_Reviewed_By:	more people than the patch
2008-08-17 23:27:27 +00:00
Tom Rhodes
41698ebf5b Document a few sysctls.
Reviewed by:	rwatson
2008-07-20 15:29:58 +00:00
Robert Watson
53640b0e3a When allocating temporary storage to hold a TCP/IP packet header
template, use an M_TEMP malloc(9) allocation rather than an mbuf
with mtod(9) and dtom(9).  This eliminates the last use of
dtom(9) in TCP.

MFC after:	3 weeks
2008-06-02 14:20:26 +00:00
Robert Watson
8501a69cc9 Convert pcbinfo and inpcb mutexes to rwlocks, and modify macros to
explicitly select write locking for all use of the inpcb mutex.
Update some pcbinfo lock assertions to assert locked rather than
write-locked, although in practice almost all uses of the pcbinfo
rwlock main exclusive, and all instances of inpcb lock acquisition
are exclusive.

This change should introduce (ideally) little functional change.
However, it lays the groundwork for significantly increased
parallelism in the TCP/IP code.

MFC after:	3 months
Tested by:	kris (superset of committered patch)
2008-04-17 21:38:18 +00:00
Mike Silbersack
4b421e2daa Add FBSDID to all files in netinet so that people can more
easily include file version information in bug reports.

Approved by:	re (kensmith)
2007-10-07 20:44:24 +00:00
Konstantin Belousov
586b4a0e50 Revert rev. 1.94. After recent tcp backouts, tcp_close() may return NULL.
Check the return value of tcp_close() being NULL before dereferencing it
in #ifdef TCPDEBUG block.

Reviewed by:	rwatson
Approved by:	re (gnn)
2007-09-24 14:46:27 +00:00
Mike Silbersack
e2f2059f68 Two changes:
- Reintegrate the ANSI C function declaration change
  from tcp_timer.c rev 1.92

- Reorganize the tcpcb structure so that it has a single
  pointer to the "tcp_timer" structure which contains all
  of the tcp timer callouts.  This change means that when
  the single tcp timer change is reintegrated, tcpcb will
  not change in size, and therefore the ABI between
  netstat and the kernel will not change.

Neither of these changes should have any functional
impact.

Reviewed by: bmah, rrs
Approved by: re (bmah)
2007-09-24 05:26:24 +00:00
Robert Watson
85d9437250 Back out tcp_timer.c:1.93 and associated changes that reimplemented the many
TCP timers as a single timer, but retain the API changes necessary to
reintroduce this change.  This will back out the source of at least two
reported problems: lock leaks in certain timer edge cases, and TCP timers
continuing to fire after a connection has closed (a bug previously fixed and
then reintroduced with the timer rewrite).

In a follow-up commit, some minor restylings and comment changes performed
after the TCP timer rewrite will be reapplied, and a further change to allow
the TCP timer rewrite to be added back without disturbing the ABI.  The new
design is believed to be a good thing, but the outstanding issues are
leading to significant stability/correctness problems that are holding
up 7.0.

This patch was generated by silby, but is being committed by proxy due to
poor network connectivity for silby this week.

Approved by:	re (kensmith)
Submitted by:	silby
Tested by:	rwatson, kris
Problems reported by:	peter, kris, others
2007-09-07 09:19:22 +00:00
Andre Oppermann
f58747375d Handle a race condition on >2 core machines in tcp_timer() when
a timer issues a shutdown and a simultaneous close on the socket
happens.  This race condition is inherent in the current socket/
inpcb life cycle system but can be handled well.

Reported by:	kris
Tested by:	kris (on 8-core machine)
2007-06-09 17:49:39 +00:00
Robert Watson
c214db75f2 In tcp_timer_2msl(), tp can never become NULL, so don't check it for
NULL before entering tcp_trace().

Found with:	Coverity Prevent(tm)
CID:		1840
2007-05-27 17:52:02 +00:00
Andre Oppermann
2104448fe7 Move TIME_WAIT related functions and timer handling from files
other than repo copied tcp_subr.c into tcp_timewait.c#1.284:

 tcp_input.c#1.350 tcp_timewait() -> tcp_twcheck()

 tcp_timer.c#1.92 tcp_timer_2msl_reset() -> tcp_tw_2msl_reset()
 tcp_timer.c#1.92 tcp_timer_2msl_stop() -> tcp_tw_2msl_stop()
 tcp_timer.c#1.92 tcp_timer_2msl_tw() -> tcp_tw_2msl_scan()

This is a mechanical move with appropriate renames and making
them static if used only locally.

The tcp_tw_2msl_scan() cleanup function is still run from the
tcp_slowtimo() in tcp_timer.c.
2007-05-16 17:14:25 +00:00
Robert Watson
f2565d68a4 Move universally to ANSI C function declarations, with relatively
consistent style(9)-ish layout.
2007-05-10 15:58:48 +00:00
Andre Oppermann
37ba9d112a Fix two comments. 2007-05-06 13:38:25 +00:00
Andre Oppermann
b8152ba793 Change the TCP timer system from using the callout system five times
directly to a merged model where only one callout, the next to fire,
is registered.

Instead of callout_reset(9) and callout_stop(9) the new function
tcp_timer_activate() is used which then internally manages the callout.

The single new callout is a mutex callout on inpcb simplifying the
locking a bit.

tcp_timer() is the called function which handles all race conditions
in one place and then dispatches the individual timer functions.

Reviewed by:	rwatson (earlier version)
2007-04-11 09:45:16 +00:00
Andre Oppermann
5dd9dfefd6 Retire unused TCP_SACK_DEBUG. 2007-04-04 14:44:15 +00:00
Andre Oppermann
ad3f9ab320 ANSIfy function declarations and remove register keywords for variables.
Consistently apply style to all function declarations.
2007-03-21 19:37:55 +00:00
Andre Oppermann
6489fe6553 Match up SYSCTL declaration style. 2007-03-19 19:00:51 +00:00
Mohan Srinivasan
7c72af8770 Reap FIN_WAIT_2 connections marked SOCANTRCVMORE faster. This mitigate
potential issues where the peer does not close, potentially leaving
thousands of connections in FIN_WAIT_2. This is controlled by a new sysctl
fast_finwait2_recycle, which is disabled by default.

Reviewed by: gnn, silby.
2007-02-26 22:25:21 +00:00
Ruslan Ermilov
751dea2935 Back when we had T/TCP support, we used to apply different
timeouts for TCP and T/TCP connections in the TIME_WAIT
state, and we had two separate timed wait queues for them.
Now that is has gone, the timeout is always 2*MSL again,
and there is no reason to keep two queues (the first was
unused anyway!).

Also, reimplement the remaining queue using a TAILQ (it
was technically impossible before, with two queues).
2006-09-07 13:06:00 +00:00
Ruslan Ermilov
3c89486cc7 Remove a microoptimization for i386 that was a micropessimization for amd64. 2006-09-07 09:49:08 +00:00
Gleb Smirnoff
2c857a9be9 o Backout rev. 1.125 of in_pcb.c. It appeared to behave extremely
bad under high load. For example with 40k sockets and 25k tcptw
  entries, connect() syscall can run for seconds. Debugging showed
  that it iterates the cycle millions times and purges thousands of
  tcptw entries at a time.
  Besides practical unusability this change is architecturally
  wrong. First, in_pcblookup_local() is used in connect() and bind()
  syscalls. No stale entries purging shouldn't be done here. Second,
  it is a layering violation.
o Return back the tcptw purging cycle to tcp_timer_2msl_tw(),
  that was removed in rev. 1.78 by rwatson. The commit log of this
  revision tells nothing about the reason cycle was removed. Now
  we need this cycle, since major cleaner of stale tcptw structures
  is removed.
o Disable probably necessary, but now unused
  tcp_twrecycleable() function.

Reviewed by:	ru
2006-09-06 13:56:35 +00:00
Mohan Srinivasan
464469c713 Fixes an edge case bug in timewait handling where ticks rolling over causing
the timewait expiry to be exactly 0 corrupts the timewait queues (and that entry).
Reviewed by:	silby
2006-08-11 21:15:23 +00:00
Robert Watson
d8ab0ec661 When entering a timer on a tcpcb, don't continue processing if it has been
dropped.  This prevents a bug introduced during the socket/pcb refcounting
work from occuring, in which occasionally the retransmit timer may fire
after a connection has been reset, resulting in the resulting R|A TCP
packet having a source port of 0, as the port reservation has been
released.

While here, fixing up some RUNLOCK->WUNLOCK bugs.

MFC after:	1 month
2006-06-03 19:37:08 +00:00
Gleb Smirnoff
ffb761f624 - Backout one line from 1.78. The tp can be freed by tcp_drop().
- Style next line.

Coverity ID:	912
2006-05-16 10:51:26 +00:00
Robert Watson
3127286870 Only return (tw) from tcp_twclose() if reuse is passed, otherwise
return NULL.  In principle this shouldn't change the behavior, but
avoids returning a potentially invalid/inappropriate pointer to
the caller.

Found with:	Coverity Prevent (tm)
Submitted by:	pjd
MFC after:	3 months
2006-05-05 06:50:23 +00:00
Robert Watson
623dce13c6 Update TCP for infrastructural changes to the socket/pcb refcount model,
pru_abort(), pru_detach(), and in_pcbdetach():

- Universally support and enforce the invariant that so_pcb is
  never NULL, converting dozens of unnecessary NULL checks into
  assertions, and eliminating dozens of unnecessary error handling
  cases in protocol code.

- In some cases, eliminate unnecessary pcbinfo locking, as it is no
  longer required to ensure so_pcb != NULL.  For example, the receive
  code no longer requires the pcbinfo lock, and the send code only
  requires it if building a new connection on an otherwise unconnected
  socket triggered via sendto() with an address.  This should
  significnatly reduce tcbinfo lock contention in the receive and send
  cases.

- In order to support the invariant that so_pcb != NULL, it is now
  necessary for the TCP code to not discard the tcpcb any time a
  connection is dropped, but instead leave the tcpcb until the socket
  is shutdown.  This case is handled by setting INP_DROPPED, to
  substitute for using a NULL so_pcb to indicate that the connection
  has been dropped.  This requires the inpcb lock, but not the pcbinfo
  lock.

- Unlike all other protocols in the tree, TCP may need to retain access
  to the socket after the file descriptor has been closed.  Set
  SS_PROTOREF in tcp_detach() in order to prevent the socket from being
  freed, and add a flag, INP_SOCKREF, so that the TCP code knows whether
  or not it needs to free the socket when the connection finally does
  close.  The typical case where this occurs is if close() is called on
  a TCP socket before all sent data in the send socket buffer has been
  transmitted or acknowledged.  If INP_SOCKREF is found when the
  connection is dropped, we release the inpcb, tcpcb, and socket instead
  of flagging INP_DROPPED.

- Abort and detach protocol switch methods no longer return failures,
  nor attempt to free sockets, as the socket layer does this.

- Annotate the existence of a long-standing race in the TCP timer code,
  in which timers are stopped but not drained when the socket is freed,
  as waiting for drain may lead to deadlocks, or have to occur in a
  context where waiting is not permitted.  This race has been handled
  by testing to see if the tcpcb pointer in the inpcb is NULL (and vice
  versa), which is not normally permitted, but may be true of a inpcb
  and tcpcb have been freed.  Add a counter to test how often this race
  has actually occurred, and a large comment for each instance where
  we compare potentially freed memory with NULL.  This will have to be
  fixed in the near future, but requires is to further address how to
  handle the timer shutdown shutdown issue.

- Several TCP calls no longer potentially free the passed inpcb/tcpcb,
  so no longer need to return a pointer to indicate whether the argument
  passed in is still valid.

- Un-macroize debugging and locking setup for various protocol switch
  methods for TCP, as it lead to more obscurity, and as locking becomes
  more customized to the methods, offers less benefit.

- Assert copyright on tcp_usrreq.c due to significant modifications that
  have been made as part of this work.

These changes significantly modify the memory management and connection
logic of our TCP implementation, and are (as such) High Risk Changes,
and likely to contain serious bugs.  Please report problems to the
current@ mailing list ASAP, ideally with simple test cases, and
optionally, packet traces.

MFC after:	3 months
2006-04-01 16:36:36 +00:00
Robert Watson
1c53f80637 Explicitly assert socket pointer is non-NULL in tcp_input() so as to
provide better debugging information.

Prefer explicit comparison to NULL for tcpcb pointers rather than
treating them as booleans.

MFC after:	1 month
2006-03-26 01:33:41 +00:00
Andre Oppermann
a4684d742d Make sysctl_msec_to_ticks(SYSCTL_HANDLER_ARGS) generally available instead
of being private to tcp_timer.c.

Sponsored by:	TCP/IP Optimization Fundraise 2005
MFC after:	3 days
2006-02-16 15:40:36 +00:00
Robert Watson
f59a9ebf10 Remove no-op spl's and most comment references to spls, as TCP locking
is believed to be basically done (modulo any remaining bugs).

MFC after:	3 days
2005-07-19 12:21:26 +00:00
Paul Saab
2cdbfa66ee Replace t_force with a t_flag (TF_FORCEDATA).
Submitted by:   Raja Mukerji.
Reviewed by:    Mohan, Silby, Andre Opperman.
2005-05-21 00:38:29 +00:00
Warner Losh
c398230b64 /* -> /*- for license, minor formatting changes 2005-01-07 01:45:51 +00:00
Robert Watson
db0aae38b6 Remove the now unused tcp_canceltimers() function. tcpcb timers are
now stopped as part of tcp_discardcb().

MFC after:	2 weeks
2004-12-23 01:25:59 +00:00
Robert Watson
950ab1e470 Remove an annotation of a minor race relating to the update of
multiple MIB entries using sysctl in short order, which might
result in unexpected values for tcp_maxidle being generated by
tcp_slowtimo.  In practice, this will not happen, or at least,
doesn't require an explicit comment.

MFC after:	2 weeks
2004-12-23 01:21:54 +00:00
Robert Watson
79a9e59c89 Assert the tcptw inpcb lock in tcp_timer_2msl_reset(), as fields in
the tcptw undergo non-atomic read-modify-writes.

MFC after:	2 weeks
2004-12-05 22:47:29 +00:00
Robert Watson
cce83ffb5a tcp_timewait() performs multiple non-atomic reads on the tcptw
structure, so assert the inpcb lock associated with the tcptw.
Also assert the tcbinfo lock, as tcp_timewait() may call
tcp_twclose() or tcp_2msl_rest(), which require it.  Since
tcp_timewait() is already called with that lock from tcp_input(),
this doesn't change current locking, merely documents reasons for
it.

In tcp_twstart(), assert the tcbinfo lock, as tcp_timer_2msl_rest()
is called, which requires that lock.

In tcp_twclose(), assert the tcbinfo lock, as tcp_timer_2msl_stop()
is called, which requires that lock.

Document the locking strategy for the time wait queues in tcp_timer.c,
which consists of protecting the time wait queues in the same manner
as the tcbinfo structure (using the tcbinfo lock).

In tcp_timer_2msl_reset(), assert the tcbinfo lock, as the time wait
queues are modified.

In tcp_timer_2msl_stop(), assert the tcbinfo lock, as the time wait
queues may be modified.

In tcp_timer_2msl_tw(), assert the tcbinfo lock, as the time wait
queues may be modified.

MFC after:	2 weeks
2004-11-23 17:21:30 +00:00
Robert Watson
b42ff86e73 De-spl tcp_slowtimo; tcp_maxidle assignment is subject to possible
but unlikely races that could be corrected by having tcp_keepcnt
and tcp_keepintvl modifications go through handler functions via
sysctl, but probably is not worth doing.  Updates to multiple
sysctls within evaluation of a single addition are unlikely.

Annotate that tcp_canceltimers() is currently unused.

De-spl tcp_timer_delack().

De-spl tcp_timer_2msl().

MFC after:	2 weeks
2004-11-23 16:45:07 +00:00
Andre Oppermann
c94c54e4df Remove RFC1644 T/TCP support from the TCP side of the network stack.
A complete rationale and discussion is given in this message
and the resulting discussion:

 http://docs.freebsd.org/cgi/mid.cgi?4177C8AD.6060706

Note that this commit removes only the functional part of T/TCP
from the tcp_* related functions in the kernel.  Other features
introduced with RFC1644 are left intact (socket layer changes,
sendmsg(2) on connection oriented protocols)  and are meant to
be reused by a simpler and less intrusive reimplemention of the
previous T/TCP functionality.

Discussed on:	-arch
2004-11-02 22:22:22 +00:00
Robert Watson
a4f757cd5d White space cleanup for netinet before branch:
- Trailing tab/space cleanup
- Remove spurious spaces between or before tabs

This change avoids touching files that Andre likely has in his working
set for PFIL hooks changes for IPFW/DUMMYNET.

Approved by:	re (scottl)
Submitted by:	Xin LI <delphij@frontfree.net>
2004-08-16 18:32:07 +00:00
Paul Saab
6d90faf3d8 Add support for TCP Selective Acknowledgements. The work for this
originated on RELENG_4 and was ported to -CURRENT.

The scoreboarding code was obtained from OpenBSD, and many
of the remaining changes were inspired by OpenBSD, but not
taken directly from there.

You can enable/disable sack using net.inet.tcp.do_sack. You can
also limit the number of sack holes that all senders can have in
the scoreboard with net.inet.tcp.sackhole_limit.

Reviewed by:	gnn
Obtained from:	Yahoo! (Mohan Srinivasan, Jayanth Vijayaraghavan)
2004-06-23 21:04:37 +00:00
Warner Losh
f36cfd49ad Remove advertising clause from University of California Regent's
license, per letter dated July 22, 1999 and email from Peter Wemm,
Alan Cox and Robert Watson.

Approved by: core, peter, alc, rwatson
2004-04-07 20:46:16 +00:00
Andre Oppermann
97d8d152c2 Introduce tcp_hostcache and remove the tcp specific metrics from
the routing table.  Move all usage and references in the tcp stack
from the routing table metrics to the tcp hostcache.

It caches measured parameters of past tcp sessions to provide better
initial start values for following connections from or to the same
source or destination.  Depending on the network parameters to/from
the remote host this can lead to significant speedups for new tcp
connections after the first one because they inherit and shortcut
the learning curve.

tcp_hostcache is designed for multiple concurrent access in SMP
environments with high contention and is hash indexed by remote
ip address.

It removes significant locking requirements from the tcp stack with
regard to the routing table.

Reviewed by:	sam (mentor), bms
Reviewed by:	-net, -current, core@kame.net (IPv6 parts)
Approved by:	re (scottl)
2003-11-20 20:07:39 +00:00
Sam Leffler
2a0746208b use local values instead of chasing pointers
Supported by:	FreeBSD Foundation
2003-11-08 22:57:13 +00:00
Jeffrey Hsu
9d11646de7 Unify the "send high" and "recover" variables as specified in the
lastest rev of the spec.  Use an explicit flag for Fast Recovery. [1]

Fix bug with exiting Fast Recovery on a retransmit timeout
diagnosed by Lu Guohan. [2]

Reviewed by:		Thomas Henderson <thomas.r.henderson@boeing.com>
Reported and tested by:	Lu Guohan <lguohan00@mails.tsinghua.edu.cn> [2]
Approved by:		Thomas Henderson <thomas.r.henderson@boeing.com>,
			Sally Floyd <floyd@acm.org> [1]
2003-07-15 21:49:53 +00:00
Jeffrey Hsu
f058535deb Compensate for decreasing the minimum retransmit timeout.
Reviewed by:	jlemon
2003-06-04 10:03:55 +00:00
Jonathan Lemon
607b0b0cc9 Remove a panic(); if the zone allocator can't provide more timewait
structures, reuse the oldest one.  Also move the expiry timer from
a per-structure callout to the tcp slow timer.

Sponsored by: DARPA, NAI Labs
2003-03-08 22:06:20 +00:00