Commit Graph

232 Commits

Author SHA1 Message Date
Maxim Konovalov
ac827533df o Teach sysctl_drop() how to deal with the sockets in TIME_WAIT state.
This is a special case because tcp_twstart() destroys a tcp control
block via tcp_discardcb() so we cannot call tcp_drop(struct *tcpcb) on
such connections.  Use tcp_twclose() instead.

MFC after:	5 days
2005-10-02 08:43:57 +00:00
Andre Oppermann
ffabe3dce8 In tcp_ctlinput() do not swap ip->ip_len a second time. It
has been done in icmp_input() already.

This fixes the ICMP_UNREACH_NEEDFRAG case where no MTU was
proposed in the ICMP reply.

PR:		kern/81813
Submitted by:	Vitezslav Novy <vita at fio.cz>
MFC after:	3 days
2005-09-10 07:43:29 +00:00
Andre Oppermann
e0aec68255 Use the correct mbuf type for MGET(). 2005-08-30 16:35:27 +00:00
Hajimu UMEMOTO
4dad226e45 recover the line which was wrongly disappeared during scope cleanup.
tcpdrop(8) should work for IPv6, again.
2005-08-01 12:08:49 +00:00
Hajimu UMEMOTO
a1f7e5f8ee scope cleanup. with this change
- most of the kernel code will not care about the actual encoding of
  scope zone IDs and won't touch "s6_addr16[1]" directly.
- similarly, most of the kernel code will not care about link-local
  scoped addresses as a special case.
- scope boundary check will be stricter.  For example, the current
  *BSD code allows a packet with src=::1 and dst=(some global IPv6
  address) to be sent outside of the node, if the application do:
    s = socket(AF_INET6);
    bind(s, "::1");
    sendto(s, some_global_IPv6_addr);
  This is clearly wrong, since ::1 is only meaningful within a single
  node, but the current implementation of the *BSD kernel cannot
  reject this attempt.

Submitted by:	JINMEI Tatuya <jinmei__at__isl.rdc.toshiba.co.jp>
Obtained from:	KAME
2005-07-25 12:31:43 +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
482ac96888 Fix for a bug in the change that defers sack option processing until
after PAWS checks. The symptom of this is an inconsistency in the cached
sack state, caused by the fact that the sack scoreboard was not being
updated for an ACK handled in the header prediction path.

Found by:	Andrey Chernov.
Submitted by:	Noritoshi Demizu, Raja Mukerji.
Approved by:	re
2005-07-01 22:54:18 +00:00
Robert Watson
e3d5315d01 Assert tcbinfo lock in tcp_drop() due to its call of tcp_close()
Assert tcbinfo lock in tcp_close() due to its call to in{,6}_detach()
Assert tcbinfo lock in tcp_drop_syn_sent() due to its call to tcp_drop()

MFC after:	7 days
2005-06-01 12:06:07 +00:00
Colin Percival
fe2eee8231 Fix two issues which were missed in FreeBSD-SA-05:08.kmem.
Reported by:	Uwe Doering
2005-05-07 00:41:36 +00:00
Andre Oppermann
9e4ca6315d If we don't get a suggested MTU during path MTU discovery
look up the packet size of the packet that generated the
response, step down the MTU by one step through ip_next_mtu()
and try again.

Suggested by:	dwmalone
2005-05-04 13:48:44 +00:00
Paul Saab
a6235da61e - Make the sack scoreboard logic use the TAILQ macros. This improves
code readability and facilitates some anticipated optimizations in
  tcp_sack_option().
- Remove tcp_print_holes() and TCP_SACK_DEBUG.

Submitted by:	Raja Mukerji.
Reviewed by:	Mohan Srinivasan, Noritoshi Demizu.
2005-04-21 20:11:01 +00:00
Andre Oppermann
1aedbd9c80 Move Path MTU discovery ICMP processing from icmp_input() to
tcp_ctlinput() and subject it to active tcpcb and sequence
number checking.  Previously any ICMP unreachable/needfrag
message would cause an update to the TCP hostcache.  Now only
ICMP PMTU messages belonging to an active TCP session with
the correct src/dst/port and sequence number will update the
hostcache and complete the path MTU discovery process.

Note that we don't entirely implement the recommended counter
measures of Section 7.2 of the paper.  However we close down
the possible degradation vector from trivially easy to really
complex and resource intensive.  In addition we have limited
the smallest acceptable MTU with net.inet.tcp.minmss sysctl
for some time already, further reducing the effect of any
degradation due to an attack.

Security:	draft-gont-tcpm-icmp-attacks-03.txt Section 7.2
MFC after:	3 days
2005-04-21 14:29:34 +00:00
Andre Oppermann
1600372b6b Ignore ICMP Source Quench messages for TCP sessions. Source Quench is
ineffective, depreciated and can be abused to degrade the performance
of active TCP sessions if spoofed.

Replace a bogus call to tcp_quench() in tcp_output() with the direct
equivalent tcpcb variable assignment.

Security:	draft-gont-tcpm-icmp-attacks-03.txt Section 7.1
MFC after:	3 days
2005-04-21 12:37:12 +00:00
Paul Saab
e346eeff65 - If the reassembly queue limit was reached or if we couldn't allocate
a reassembly queue state structure, don't update (receiver) sack
  report.
- Similarly, if tcp_drain() is called, freeing up all items on the
  reassembly queue, clean the sack report.

Found, Submitted by:	Noritoshi Demizu <demizu at dd dot iij4u dot or dot jp>
Reviewed by:	Mohan Srinivasan (mohans at yahoo-inc dot com),
		Raja Mukerji (raja at moselle dot com).
2005-04-10 05:21:29 +00:00
Gleb Smirnoff
31199c8463 Use NET_CALLOUT_MPSAFE macro. 2005-03-01 12:01:17 +00:00
Maxim Konovalov
9945c0e21f o Add handling of an IPv4-mapped IPv6 address.
o Use SYSCTL_IN() macro instead of direct call of copyin(9).

Submitted by:	ume

o Move sysctl_drop() implementation to sys/netinet/tcp_subr.c where
most of tcp sysctls live.
o There are net.inet[6].tcp[6].getcred sysctls already, no needs in
a separate struct tcp_ident_mapping.

Suggested by:	ume
2005-02-14 07:37:51 +00:00
Hajimu UMEMOTO
6d0a982bdf teach scope of IPv6 address to net.inet6.tcp6.getcred.
MFC after:	1 week
2005-02-04 14:43:05 +00:00
Robert Watson
06456da2c6 Update an additional reference to the rate of ISN tick callouts that was
missed in tcp_subr.c:1.216: projected_offset must also reflect how often
the tcp_isn_tick() callout will fire.

MFC after:	2 weeks
Submitted by:	silby
2005-01-31 01:35:01 +00:00
Robert Watson
54082796aa Have tcp_isn_tick() fire 100 times a second, rather than HZ times a
second; since the default hz has changed to 1000 times a second,
this resulted in unecessary work being performed.

MFC after:		2 weeks
Discussed with:		phk, cperciva
General head nod:	silby
2005-01-30 23:30:28 +00:00
Warner Losh
c398230b64 /* -> /*- for license, minor formatting changes 2005-01-07 01:45:51 +00:00
Robert Watson
452d9f5b1c Attempt to consistently use () around return values in calls to
return() in newer code (sysctl, ISN, timewait).
2004-12-23 01:34:26 +00:00
Robert Watson
06da46b241 Remove an XXXRW comment relating to whether or not the TCP timers are
MPSAFE: they are now believed to be.

Correct a typo in a second comment.

MFC after:	2 weeks
2004-12-23 01:27:13 +00:00
Robert Watson
b9155d92b2 Assert inpcb lock in:
tcpip_fillheaders()
  tcp_discardcb()
  tcp_close()
  tcp_notify()
  tcp_new_isn()
  tcp_xmit_bandwidth_limit()

Fix a locking comment in tcp_twstart(): the pcbinfo will be locked (and
is asserted).

MFC after:	2 weeks
2004-12-05 22:27:53 +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
7258e91f0f Assert the inpcb lock in tcp_twstart(), which does both read-modify-write
on the tcpcb, but also calls into tcp_close() and tcp_twrespond().

Annotate that tcp_twrecycleable() requires the inpcb lock because it does
a series of non-atomic reads of the tcpcb, but is currently called
without the inpcb lock by the caller.  This is a bug.

Assert the inpcb lock in tcp_twclose() as it performs a read-modify-write
of the timewait structure/inpcb, and calls in_pcbdetach() which requires
the lock.

Assert the inpcb lock in tcp_twrespond(), as it performs multiple
non-atomic reads of the tcptw and inpcb structures, as well as calling
mac_create_mbuf_from_inpcb(), tcpip_fillheaders(), which require the
inpcb lock.

MFC after:	2 weeks
2004-11-23 16:23:13 +00:00
Robert Watson
8263bab34d Assert inpcb lock in tcp_quench(), tcp_drop_syn_sent(), tcp_mtudisc(),
and tcp_drop(), due to read-modify-write of TCP state variables.

MFC after:	2 weeks
2004-11-23 16:06:15 +00:00
Robert Watson
8438db0f59 Assert the tcbinfo write lock in tcp_new_isn(), as the tcbinfo lock
protects access to the ISN state variables.

Acquire the tcbinfo write lock in tcp_isn_tick() to synchronize
timer-driven isn bumping.

Staticize internal ISN variables since they're not used outside of
tcp_subr.c.

MFC after:	2 weeks
2004-11-23 15:59:43 +00:00
SUZUKI Shinsuke
3d54848fc2 support TCP-MD5(IPv4) in KAME-IPSEC, too.
MFC after: 3 week
2004-11-08 18:49:51 +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
81158452be Push acquisition of the accept mutex out of sofree() into the caller
(sorele()/sotryfree()):

- This permits the caller to acquire the accept mutex before the socket
  mutex, avoiding sofree() having to drop the socket mutex and re-order,
  which could lead to races permitting more than one thread to enter
  sofree() after a socket is ready to be free'd.

- This also covers clearing of the so_pcb weak socket reference from
  the protocol to the socket, preventing races in clearing and
  evaluation of the reference such that sofree() might be called more
  than once on the same socket.

This appears to close a race I was able to easily trigger by repeatedly
opening and resetting TCP connections to a host, in which the
tcp_close() code called as a result of the RST raced with the close()
of the accepted socket in the user process resulting in simultaneous
attempts to de-allocate the same socket.  The new locking increases
the overhead for operations that may potentially free the socket, so we
will want to revise the synchronization strategy here as we normalize
the reference counting model for sockets.  The use of the accept mutex
in freeing of sockets that are not listen sockets is primarily
motivated by the potential need to remove the socket from the
incomplete connection queue on its parent (listen) socket, so cleaning
up the reference model here may allow us to substantially weaken the
synchronization requirements.

RELENG_5_3 candidate.

MFC after:	3 days
Reviewed by:	dwhite
Discussed with:	gnn, dwhite, green
Reported by:	Marc UBM Bocklet <ubm at u-boot-man dot de>
Reported by:	Vlad <marchenko at gmail dot com>
2004-10-18 22:19:43 +00:00
Paul Saab
a55db2b6e6 - Estimate the amount of data in flight in sack recovery and use it
to control the packets injected while in sack recovery (for both
  retransmissions and new data).
- Cleanups to the sack codepaths in tcp_output.c and tcp_sack.c.
- Add a new sysctl (net.inet.tcp.sack.initburst) that controls the
  number of sack retransmissions done upon initiation of sack recovery.

Submitted by:	Mohan Srinivasan <mohans@yahoo-inc.com>
2004-10-05 18:36:24 +00:00
John-Mark Gurney
b5d47ff592 fix up socket/ip layer violation... don't assume/know that
SO_DONTROUTE == IP_ROUTETOIF and SO_BROADCAST == IP_ALLOWBROADCAST...
2004-09-05 02:34:12 +00:00
Andre Oppermann
6f2d4ea6f8 For IPv6 access pointer to tcpcb only after we have checked it is valid.
Found by:	Coverity's automated analysis (via Ted Unangst)
2004-08-19 20:16:17 +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
David Malone
849112666a In tcp6_ctlinput, lock tcbinfo around the call to syncache_unreach
so that the locks held are the same as the IPv4 case.

Reviewed by:	rwatson
2004-08-12 18:19:36 +00:00
Andre Oppermann
420a281164 Backout removal of UMA_ZONE_NOFREE flag for all zones which are established
for structures with timers in them.  It might be that a timer might fire
even when the associated structure has already been free'd.  Having type-
stable storage in this case is beneficial for graceful failure handling and
debugging.

Discussed with:	bosko, tegge, rwatson
2004-08-11 20:30:08 +00:00
Andre Oppermann
4efb805c0c Remove the UMA_ZONE_NOFREE flag to all uma_zcreate() calls in the IP and
TCP code.  This flag would have prevented giving back excessive free slabs
to the global pool after a transient peak usage.
2004-08-11 17:08:31 +00:00
Robert Watson
f31f65a708 Pass pcbinfo structures to in6_pcbnotify() rather than pcbhead
structures, allowing in6_pcbnotify() to lock the pcbinfo and each
inpcb that it notifies of ICMPv6 events.  This prevents inpcb
assertions from firing when IPv6 generates and delievers event
notifications for inpcbs.

Reported by:	kuriyama
Tested by:	kuriyama
2004-08-06 03:45:45 +00:00
Andre Oppermann
24a098ea9b o Move the inflight sysctls to their own sub-tree under net.inet.tcp to be
more consistent with the other sysctls around it.
2004-08-03 13:54:11 +00:00
Colin Percival
56f21b9d74 Rename suser_cred()'s PRISON_ROOT flag to SUSER_ALLOWJAIL. This is
somewhat clearer, but more importantly allows for a consistent naming
scheme for suser_cred flags.

The old name is still defined, but will be removed in a few days (unless I
hear any complaints...)

Discussed with:	rwatson, scottl
Requested by:	jhb
2004-07-26 07:24:04 +00:00
Jayanth Vijayaraghavan
04f0d9a0ea Let IN_FASTREOCOVERY macro decide if we are in recovery mode.
Nuke sackhole_limit for now. We need to add it back to limit the total
number of sack blocks in the system.
2004-07-19 22:37:33 +00:00
Paul Saab
76947e3222 Move the sack sysctl's under net.inet.tcp.sack
net.inet.tcp.do_sack -> net.inet.tcp.sack.enable
net.inet.tcp.sackhole_limit -> net.inet.tcp.sack.sackhole_limit

Requested by:	wollman
2004-06-23 21:34:07 +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
Robert Watson
d330008e3b If debug.mpsafenet is set, initialize TCP callouts as CALLOUT_MPSAFE. 2004-06-20 21:44:50 +00:00
Robert Watson
395a08c904 Extend coverage of SOCK_LOCK(so) to include so_count, the socket
reference count:

- Assert SOCK_LOCK(so) macros that directly manipulate so_count:
  soref(), sorele().

- Assert SOCK_LOCK(so) in macros/functions that rely on the state of
  so_count: sofree(), sotryfree().

- Acquire SOCK_LOCK(so) before calling these functions or macros in
  various contexts in the stack, both at the socket and protocol
  layers.

- In some cases, perform soisdisconnected() before sotryfree(), as
  this could result in frobbing of a non-present socket if
  sotryfree() actually frees the socket.

- Note that sofree()/sotryfree() will release the socket lock even if
  they don't free the socket.

Submitted by:	sam
Sponsored by:	FreeBSD Foundation
Obtained from:	BSD/OS
2004-06-12 20:47:32 +00:00
Robert Watson
c18b97c630 Switch to using the inpcb MAC label instead of socket MAC label when
labeling new mbufs created from sockets/inpcbs in IPv4.  This helps avoid
the need for socket layer locking in the lower level network paths
where inpcb locks are already frequently held where needed.  In
particular:

- Use the inpcb for label instead of socket in raw_append().
- Use the inpcb for label instead of socket in tcp_output().
- Use the inpcb for label instead of socket in tcp_respond().
- Use the inpcb for label instead of socket in tcp_twrespond().
- Use the inpcb for label instead of socket in syncache_respond().

While here, modify tcp_respond() to avoid assigning NULL to a stack
variable and centralize assertions about the inpcb when inp is
assigned.

Obtained from:	TrustedBSD Project
Sponsored by:	DARPA, McAfee Research
2004-05-04 02:11:47 +00:00
Mike Silbersack
c1537ef063 Enhance our RFC1948 implementation to perform better in some pathlogical
TIME_WAIT recycling cases I was able to generate with http testing tools.

In short, as the old algorithm relied on ticks to create the time offset
component of an ISN, two connections with the exact same host, port pair
that were generated between timer ticks would have the exact same sequence
number.  As a result, the second connection would fail to pass the TIME_WAIT
check on the server side, and the SYN would never be acknowledged.

I've "fixed" this by adding random positive increments to the time component
between clock ticks so that ISNs will *always* be increasing, no matter how
quickly the port is recycled.

Except in such contrived benchmarking situations, this problem should never
come up in normal usage...  until networks get faster.

No MFC planned, 4.x is missing other optimizations that are needed to even
create the situation in which such quick port recycling will occur.
2004-04-20 06:33:39 +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
Robert Watson
47f32f6fa6 Two missed in previous commit -- compare pointer with NULL rather than
using it as a boolean.
2004-04-05 00:52:05 +00:00
Robert Watson
24459934e9 Prefer NULL to 0 when checking pointer values as integers or booleans. 2004-04-05 00:49:07 +00:00