Commit Graph

247 Commits

Author SHA1 Message Date
Sam Leffler
3d0b255a9a o add missing inpcb locking in tcp_respond
o replace spl's with lock assertions

Supported by:	FreeBSD Foundation
2003-11-11 17:54:47 +00:00
Sam Leffler
383df78dc8 use Giant-less callouts when debug_mpsafenet is non-zero
Supported by:	FreeBSD Foundation
2003-11-10 23:29:33 +00:00
Jeffrey Hsu
1ce43e2348 Mark TCP syncache timer as not Giant-free ready yet. 2003-11-10 20:42:04 +00:00
Hajimu UMEMOTO
0f9ade718d - cleanup SP refcnt issue.
- share policy-on-socket for listening socket.
- don't copy policy-on-socket at all.  secpolicy no longer contain
  spidx, which saves a lot of memory.
- deep-copy pcb policy if it is an ipsec policy.  assign ID field to
  all SPD entries.  make it possible for racoon to grab SPD entry on
  pcb.
- fixed the order of searching SA table for packets.
- fixed to get a security association header.  a mode is always needed
  to compare them.
- fixed that the incorrect time was set to
  sadb_comb_{hard|soft}_usetime.
- disallow port spec for tunnel mode policy (as we don't reassemble).
- an user can define a policy-id.
- clear enc/auth key before freeing.
- fixed that the kernel crashed when key_spdacquire() was called
  because key_spdacquire() had been implemented imcopletely.
- preparation for 64bit sequence number.
- maintain ordered list of SA, based on SA id.
- cleanup secasvar management; refcnt is key.c responsibility;
  alloc/free is keydb.c responsibility.
- cleanup, avoid double-loop.
- use hash for spi-based lookup.
- mark persistent SP "persistent".
  XXX in theory refcnt should do the right thing, however, we have
  "spdflush" which would touch all SPs.  another solution would be to
  de-register persistent SPs from sptree.
- u_short -> u_int16_t
- reduce kernel stack usage by auto variable secasindex.
- clarify function name confusion.  ipsec_*_policy ->
  ipsec_*_pcbpolicy.
- avoid variable name confusion.
  (struct inpcbpolicy *)pcb_sp, spp (struct secpolicy **), sp (struct
  secpolicy *)
- count number of ipsec encapsulations on ipsec4_output, so that we
  can tell ip_output() how to handle the packet further.
- When the value of the ul_proto is ICMP or ICMPV6, the port field in
  "src" of the spidx specifies ICMP type, and the port field in "dst"
  of the spidx specifies ICMP code.
- avoid from applying IPsec transport mode to the packets when the
  kernel forwards the packets.

Tested by:	nork
Obtained from:	KAME
2003-11-04 16:02:05 +00:00
Mike Silbersack
184dcdc7c8 Change all SYSCTLS which are readonly and have a related TUNABLE
from CTLFLAG_RD to CTLFLAG_RDTUN so that sysctl(8) can provide
more useful error messages.
2003-10-21 18:28:36 +00:00
Sam Leffler
c06eb4e293 Change instances of callout_init that specify MPSAFE behaviour to
use CALLOUT_MPSAFE instead of "1" for the second parameter.  This
does not change the behaviour; it just makes the intent more clear.
2003-08-19 17:51:11 +00:00
Hartmut Brandt
a9ca5bdbd0 The syncache has made use of TCPDEBUG problematic, because the SYN
segments are lost for the application. This broke, for example,
ports/benchmarks/dbs which needs the SYN segment to filter the
contents of the trace buffer for the connection it is interested in.

This patch makes the SYN segments available again. Unfortunately they
are now associated with the listening socket instead of the new one, so
a change to applications is required, but without this patch it wouldn't
work altogether.

PR:		kern/45966
2003-08-13 10:20:57 +00:00
Jeffrey Hsu
a12569ec4f Drop Giant around syncache timer processing. 2003-07-17 11:19:25 +00:00
Mike Silbersack
af9c7d06d5 Fix a comment which didn't match the new cookie behavior.
Submitted by:	Scott Renfro <scott@renfro.org>
MFC after:	1 day
2003-02-24 03:15:48 +00:00
Mike Silbersack
a432399c56 Improve the security and performance of syncookies:
Security improvements:
- Increase the size of each syncookie secret from 32 to 128 bits
  in order to make brute force attacks on the secrets much more
  difficult.
- Always return the lowest order dword from the MD5 hash; this
  allows us to expose 2 more bits of the cookie and makes ACK
  floods which seek to guess the cookie value more difficult.

Performance improvements:
- Increase the lifetime of each syncookie from 4 seconds to 16
  seconds.  This increases the usefulness of syncookies during
  an attack.
- From Yahoo!: Reduce the number of calls to MD5Update; this
  results in a ~17% increase in cookie generation time here.

Reviewed by:	hsu, jayanth, jlemon, nectar
MFC After:	15 seconds
2003-02-23 19:04:23 +00:00
Warner Losh
a163d034fa Back out M_* changes, per decision of the TRB.
Approved by: trb
2003-02-19 05:47:46 +00:00
Jeffrey Hsu
6d45d64a8f Properly document that syncache timer processing requires an
exclusive TCP protocol lock.
2003-02-12 00:42:12 +00:00
Mike Silbersack
d4d5315c23 Fix a bug with syncookies; previously, the syncache's MSS size was not
initialized until after a syncookie was generated.  As a result,
all connections resulting from a returned cookie would end up using
a MSS of ~512 bytes.  Now larger packets will be used where possible.

MFC after:	5 days
2003-01-29 03:49:49 +00:00
Alfred Perlstein
44956c9863 Remove M_TRYWAIT/M_WAITOK/M_WAIT. Callers should use 0.
Merge M_NOWAIT/M_DONTWAIT into a single flag M_NOWAIT.
2003-01-21 08:56:16 +00:00
Jeffrey Hsu
b21bf9a59b Validate inp before de-referencing it.
Submitted by:	pb
2003-01-05 07:56:24 +00:00
Pierre Beyssac
1ba7727b9e Remove forgotten INP_UNLOCK(inp) in my previous commit.
Reported by: hsu
2002-12-22 13:04:08 +00:00
Pierre Beyssac
87cd4001b5 In syncache_timer(), don't attempt to lock the inpcb structure
associated with the syncache entry: in case tcp_close() has been
called on the corresponding listening socket, the lock has been
destroyed as a side effect of in_pcbdetach(), causing a panic when
we attempt to lock on it.

Reviewed by:	hsu
2002-12-21 19:59:47 +00:00
Jeffrey Hsu
9a39fc9d73 Eliminate a goto.
Fix some line breaks.
2002-12-20 11:24:02 +00:00
Jeffrey Hsu
f320a1bfd2 Expand scope of TCP protocol lock to cover syncache data structures. 2002-12-20 00:24:19 +00:00
Alfred Perlstein
29f194457c Fix instances of macros with improperly parenthasized arguments.
Verified by: md5
2002-11-09 12:55:07 +00:00
Sam Leffler
b9234fafa0 Tie new "Fast IPsec" code into the build. This involves the usual
configuration stuff as well as conditional code in the IPv4 and IPv6
areas.  Everything is conditional on FAST_IPSEC which is mutually
exclusive with IPSEC (KAME IPsec implmentation).

As noted previously, don't use FAST_IPSEC with INET6 at the moment.

Reviewed by:	KAME, rwatson
Approved by:	silence
Supported by:	Vernier Networks
2002-10-16 02:25:05 +00:00
Sam Leffler
5d84645305 Replace aux mbufs with packet tags:
o instead of a list of mbufs use a list of m_tag structures a la openbsd
o for netgraph et. al. extend the stock openbsd m_tag to include a 32-bit
  ABI/module number cookie
o for openbsd compatibility define a well-known cookie MTAG_ABI_COMPAT and
  use this in defining openbsd-compatible m_tag_find and m_tag_get routines
o rewrite KAME use of aux mbufs in terms of packet tags
o eliminate the most heavily used aux mbufs by adding an additional struct
  inpcb parameter to ip_output and ip6_output to allow the IPsec code to
  locate the security policy to apply to outbound packets
o bump __FreeBSD_version so code can be conditionalized
o fixup ipfilter's call to ip_output based on __FreeBSD_version

Reviewed by:	julian, luigi (silent), -arch, -net, darren
Approved by:	julian, silence from everyone else
Obtained from:	openbsd (mostly)
MFC after:	1 month
2002-10-16 01:54:46 +00:00
Mike Silbersack
a9ce5e05b5 Handle PMTU discovery in syn-ack packets slightly differently;
rely on syncache flags instead of directly accessing the route
entry.

MFC after:	3 days
2002-08-05 22:34:15 +00:00
Robert Watson
c488362e1a Introduce support for Mandatory Access Control and extensible
kernel access control.

Instrument the TCP socket code for packet generation and delivery:
label outgoing mbufs with the label of the socket, and check socket and
mbuf labels before permitting delivery to a socket.  Assign labels
to newly accepted connections when the syncache/cookie code has done
its business.  Also set peer labels as convenient.  Currently,
MAC policies cannot influence the PCB matching algorithm, so cannot
implement polyinstantiation.  Note that there is at least one case
where a PCB is not available due to the TCP packet not being associated
with any socket, so we don't label in that case, but need to handle
it in a special manner.

Obtained from:	TrustedBSD Project
Sponsored by:	DARPA, NAI Labs
2002-07-31 19:06:49 +00:00
Jonathan Lemon
0080a004d7 One possible code path for syncache_respond() is:
syncache_respond(A), ip_output(), ip_input(), tcp_input(), syncache_badack(B)

Which winds up deleting a different entry from the syncache.  Handle
this by not utilizing the next entry in the timer chain until after
syncache_respond() completes.  The case of A == B should not be possible.

Problem found by: Don Bowman <don@sandvine.com>
2002-06-28 19:12:38 +00:00
Mike Silbersack
eb5afeba22 Re-commit w/fix:
Ensure that the syn cache's syn-ack packets contain the same
  ip_tos, ip_ttl, and DF bits as all other tcp packets.

  PR:             39141
  MFC after:      2 weeks

This time, make sure that ipv4 specific code (aka all of the above)
is only run in the ipv4 case.
2002-06-14 03:08:05 +00:00
Mike Silbersack
70d2b17029 Back out ip_tos/ip_ttl/DF "fix", it just panic'd my box. :)
Pointy-hat to:	silby
2002-06-14 02:43:20 +00:00
Mike Silbersack
21c3b2fc69 Ensure that the syn cache's syn-ack packets contain the same
ip_tos, ip_ttl, and DF bits as all other tcp packets.

PR:		39141
MFC after:	2 weeks
2002-06-14 02:36:34 +00:00
Jeffrey Hsu
e98d6424af Every array elt is initialized in the following loop, so remove
unnecessary M_ZERO.
2002-06-10 23:48:37 +00:00
Jeffrey Hsu
f76fcf6d4c Lock up inpcb.
Submitted by:	Jennifer Yang <yangjihui@yahoo.com>
2002-06-10 20:05:46 +00:00
Robert Watson
f83c7ad731 Modify the arguments to syncache_socket() to include the mbuf (m) that
results in the syncache entry being turned into a socket.  While it's
not used in the main tree, this is required in the MAC tree so that
labels can be propagated from the mbuf to the socket.  This is also
useful if you're doing things like transparent IP connection hijacking
and you want to use the syncache/cookie mechanism, but we won't go
there.

Obtained from:	TrustedBSD Project
Sponsored by:	DARPA, NAI Labs
2002-05-14 18:57:55 +00:00
Jeff Roberson
69c2d429c1 Switch vm_zone.h with uma.h. Change over to uma interfaces. 2002-03-20 05:48:55 +00:00
Jeff Roberson
8355f576a9 This is the first part of the new kernel memory allocator. This replaces
malloc(9) and vm_zone with a slab like allocator.

Reviewed by:	arch@
2002-03-19 09:11:49 +00:00
Robert Watson
16aae019a0 NAI DBA update 2002-03-14 16:53:39 +00:00
Hajimu UMEMOTO
b7d6d9526c - Set inc_isipv6 in tcp6_usr_connect().
- When making a pcb from a sync cache, do not forget to copy inc_isipv6.

Obtained from:	KAME
MFC After:	1 week
2002-02-28 17:11:10 +00:00
Jonathan Lemon
6b33ceb8e3 When expanding a syncache entry into a socket, inherit the socket options
from the current listen socket instead of the cached (and possibly stale)
TCB pointer.
2002-02-20 16:47:11 +00:00
Jonathan Lemon
0cab7c4b08 When a duplicate SYN arrives which matches an entry in the syncache,
update our lazy reference to the inpcb structure, as it may have changed.

Found by: dima
2002-02-12 02:03:50 +00:00
Julian Elischer
079b7badea Pre-KSE/M3 commit.
this is a low-functionality change that changes the kernel to access the main
thread of a process via the linked list of threads rather than
assuming that it is embedded in the process. It IS still embeded there
but remove all teh code that assumes that in preparation for the next commit
which will actually move it out.

Reviewed by: peter@freebsd.org, gallatin@cs.duke.edu, benno rice,
2002-02-07 20:58:47 +00:00
Jonathan Lemon
d9b7cc1c8d The ENDPTS_EQ macro was comparing the one of the fports to itself. Fix.
Submitted by: emy@boostworks.com
2002-01-22 17:54:28 +00:00
Jonathan Lemon
45a0329051 If syncookies are disabled (net.inet.tcp.syncookies) then use the faster
arc4random() routine to generate ISNs instead of creating them with MD5().

Suggested by: silby
2001-12-21 04:41:08 +00:00
Jonathan Lemon
e579ba1aea When storing an int value in a void *, use intptr_t as the cast type
(instead of int) to keep the 64 bit platforms happy.
2001-12-19 15:57:43 +00:00
Jonathan Lemon
a9c9684163 Extend the SYN DoS defense by adding syncookies to the syncache.
All TCP ISNs that are sent out are valid cookies, which allows entries
in the syncache to be dropped and still have the ACK accepted later.
As all entries pass through the syncache, there is no sudden switchover
from cache -> cookies when the cache is full; instead, syncache entries
simply have a reduced lifetime.  More details may be found in the
"Resisting DoS attacks with a SYN cache" paper in the Usenix BSDCon 2002
conference proceedings.

Sponsored by: DARPA, NAI Labs
2001-12-19 06:12:14 +00:00
Jonathan Lemon
04cad5adb1 Undo one of my last minute changes; move sc_iss up earlier so it
is initialized in case we take the T/TCP path.
2001-12-13 04:05:26 +00:00
Matthew Dillon
262c1c1a4e Fix a bug with transmitter restart after receiving a 0 window. The
receiver was not sending an immediate ack with delayed acks turned on
when the input buffer is drained, preventing the transmitter from
restarting immediately.

Propogate the TCP_NODELAY option to accept()ed sockets.  (Helps tbench and
is a good idea anyway).

Some cleanup.  Identify additonal issues in comments.

MFC after:	1 day
2001-12-02 08:49:29 +00:00
Seigo Tanimura
df89626872 Clear a new syncache entry first, followed by filling in values. This
fixes route breakage due to uncleared gabage on my box.
2001-11-27 11:55:28 +00:00
Bruce Evans
419d3454b1 Fixed a buffer overrun. In my kernel configuration, tcp_syncache happens
to be followed by nfsnodehashtbl, so bzeroing callouts beyond the end of
tcp_syncache soon caused a null pointer panic when nfsnodehashtbl was
accessed.
2001-11-23 12:31:27 +00:00
Jonathan Lemon
be2ac88c59 Introduce a syncache, which enables FreeBSD to withstand a SYN flood
DoS in an improved fashion over the existing code.

Reviewed by: silby  (in a previous iteration)
Sponsored by: DARPA, NAI Labs
2001-11-22 04:50:44 +00:00