Commit Graph

88 Commits

Author SHA1 Message Date
Robert Watson
430c635447 Correct a bug introduced with reduced TCP state handling; make
sure that the MAC label on TCP responses during TIMEWAIT is
properly set from either the socket (if available), or the mbuf
that it's responding to.

Unfortunately, this is made somewhat difficult by the TCP code,
as tcp_twstart() calls tcp_twrespond() after discarding the socket
but without a reference to the mbuf that causes the "response".
Passing both the socket and the mbuf works arounds this--eventually
it might be good to make sure the mbuf always gets passed in in
"response" scenarios but working through this provided to
complicate things too much.

Approved by:	re (scottl)
Reviewed by:	hsu
Obtained from:	TrustedBSD Project
Sponsored by:	DARPA, Network Associates Laboratories
2003-05-07 05:26:27 +00:00
Jeffrey Hsu
48d2549c3e Observe conservation of packets when entering Fast Recovery while
doing Limited Transmit.  Only artificially inflate the congestion
window by 1 segment instead of the usual 3 to take into account
the 2 already sent by Limited Transmit.

Approved in principle by:	Mark Allman <mallman@grc.nasa.gov>,
Hari Balakrishnan <hari@nms.lcs.mit.edu>, Sally Floyd <floyd@icir.org>
2003-04-01 21:16:46 +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
Jonathan Lemon
340c35de6a Add a TCP TIMEWAIT state which uses less space than a fullblown TCP
control block.  Allow the socket and tcpcb structures to be freed
earlier than inpcb.  Update code to understand an inp w/o a socket.

Reviewed by: hsu, silby, jayanth
Sponsored by: DARPA, NAI Labs
2003-02-19 22:32:43 +00:00
Jonathan Lemon
7990938421 Convert tcp_fillheaders(tp, ...) -> tcpip_fillheaders(inp, ...) so the
routine does not require a tcpcb to operate.  Since we no longer keep
template mbufs around, move pseudo checksum out of this routine, and
merge it with the length update.

Sponsored by: DARPA, NAI Labs
2003-02-19 22:18:06 +00:00
Jeffrey Hsu
cb942153c8 Fix NewReno.
Reviewed by: Tom Henderson <thomas.r.henderson@boeing.com>
2003-01-13 11:01:20 +00:00
Matthew Dillon
1fcc99b5de Implement TCP bandwidth delay product window limiting, similar to (but
not meant to duplicate) TCP/Vegas.  Add four sysctls and default the
implementation to 'off'.

net.inet.tcp.inflight_enable	enable algorithm (defaults to 0=off)
net.inet.tcp.inflight_debug	debugging (defaults to 1=on)
net.inet.tcp.inflight_min	minimum window limit
net.inet.tcp.inflight_max	maximum window limit

MFC after:	1 week
2002-08-17 18:26:02 +00:00
Matthew Dillon
d65bf08af3 Add the tcps_sndrexmitbad statistic, keep track of late acks that caused
unnecessary retransmissions.
2002-07-19 18:29:38 +00:00
Jeffrey Hsu
3ce144ea88 Notify functions can destroy the pcb, so they have to return an
indication of whether this happenned so the calling function
knows whether or not to unlock the pcb.

Submitted by:	Jennifer Yang (yangjihui@yahoo.com)
Bug reported by:  Sid Carter (sidcarter@symonds.net)
2002-06-14 08:35:21 +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
f76fcf6d4c Lock up inpcb.
Submitted by:	Jennifer Yang <yangjihui@yahoo.com>
2002-06-10 20:05:46 +00:00
Alfred Perlstein
4d77a549fe Remove __P. 2002-03-19 21:25:46 +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
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
Jayanth Vijayaraghavan
c24d5dae7a Add a flag TF_LASTIDLE, that forces a previously idle connection
to send all its data, especially when the data is less than one MSS.
This fixes an issue where the stack was delaying the sending
of data, eventhough there was enough window to send all the data and
the sending of data was emptying the socket buffer.

Problem found by Yoshihiro Tsuchiya (tsuchiya@flab.fujitsu.co.jp)

Submitted by: Jayanth Vijayaraghavan
2001-10-05 21:33:38 +00:00
Julian Elischer
f0ffb944d2 Patches from Keiichi SHIMA <keiichi@iij.ad.jp>
to make ip use the standard protosw structure again.

Obtained from: Well, KAME I guess.
2001-09-03 20:03:55 +00:00
Mike Silbersack
b0e3ad758b Much delayed but now present: RFC 1948 style sequence numbers
In order to ensure security and functionality, RFC 1948 style
initial sequence number generation has been implemented.  Barring
any major crypographic breakthroughs, this algorithm should be
unbreakable.  In addition, the problems with TIME_WAIT recycling
which affect our currently used algorithm are not present.

Reviewed by: jesper
2001-08-22 00:58:16 +00:00
Mike Silbersack
2d610a5028 Temporary feature: Runtime tuneable tcp initial sequence number
generation scheme.  Users may now select between the currently used
OpenBSD algorithm and the older random positive increment method.

While the OpenBSD algorithm is more secure, it also breaks TIME_WAIT
handling; this is causing trouble for an increasing number of folks.

To switch between generation schemes, one sets the sysctl
net.inet.tcp.tcp_seq_genscheme.  0 = random positive increments,
1 = the OpenBSD algorithm.  1 is still the default.

Once a secure _and_ compatible algorithm is implemented, this sysctl
will be removed.

Reviewed by: jlemon
Tested by: numerous subscribers of -net
2001-07-08 02:20:47 +00:00
Mike Silbersack
08517d530e Eliminate the allocation of a tcp template structure for each
connection.  The information contained in a tcptemp can be
reconstructed from a tcpcb when needed.

Previously, tcp templates required the allocation of one
mbuf per connection.  On large systems, this change should
free up a large number of mbufs.

Reviewed by:	bmilekic, jlemon, ru
MFC after: 2 weeks
2001-06-23 03:21:46 +00:00
Kris Kennaway
f0a04f3f51 Randomize the TCP initial sequence numbers more thoroughly.
Obtained from:	OpenBSD
Reviewed by:	jesper, peter, -developers
2001-04-17 18:08:01 +00:00
Jonathan Lemon
c693a045de Remove in_pcbnotify and use in_pcblookup_hash to find the cb directly.
For TCP, verify that the sequence number in the ICMP packet falls within
the tcp receive window before performing any actions indicated by the
icmp packet.

Clean up some layering violations (access to tcp internals from in_pcb)
2001-02-26 21:19:47 +00:00
Jesper Skriver
694a9ff95b Remove tcp_drop_all_states, which is unneeded after jlemon removed it
from tcp_subr.c in rev 1.92
2001-02-25 17:20:19 +00:00
Poul-Henning Kamp
90fcbbd635 Remove unneeded loop increment in src/sys/netinet/in_pcb.c:in_pcbnotify
Add new PRC_UNREACH_ADMIN_PROHIB in sys/sys/protosw.h

Remove condition on TCP in src/sys/netinet/ip_icmp.c:icmp_input

In src/sys/netinet/ip_icmp.c:icmp_input set code = PRC_UNREACH_ADMIN_PROHIB
or PRC_UNREACH_HOST for all unreachables except ICMP_UNREACH_NEEDFRAG

Rename sysctl icmp_admin_prohib_like_rst to icmp_unreach_like_rst
to reflect the fact that we also react on ICMP unreachables that
are not administrative prohibited.  Also update the comments to
reflect this.

In sys/netinet/tcp_subr.c:tcp_ctlinput add code to treat
PRC_UNREACH_ADMIN_PROHIB and PRC_UNREACH_HOST different.

PR:		23986
Submitted by:	Jesper Skriver <jesper@skriver.dk>
2001-02-18 09:34:55 +00:00
Poul-Henning Kamp
442fad6798 Update the "icmp_admin_prohib_like_rst" code to check the tcp-window and
to be configurable with respect to acting only in SYN or in all TCP states.

PR:		23665
Submitted by:	Jesper Skriver <jesper@skriver.dk>
2000-12-24 10:57:21 +00:00
Poul-Henning Kamp
b11d7a4a2f We currently does not react to ICMP administratively prohibited
messages send by routers when they deny our traffic, this causes
a timeout when trying to connect to TCP ports/services on a remote
host, which is blocked by routers or firewalls.

rfc1122 (Requirements for Internet Hosts) section 3.2.2.1 actually
requi re that we treat such a message for a TCP session, that we
treat it like if we had recieved a RST.

quote begin.

            A Destination Unreachable message that is received MUST be
            reported to the transport layer.  The transport layer SHOULD
            use the information appropriately; for example, see Sections
            4.1.3.3, 4.2.3.9, and 4.2.4 below.  A transport protocol
            that has its own mechanism for notifying the sender that a
            port is unreachable (e.g., TCP, which sends RST segments)
            MUST nevertheless accept an ICMP Port Unreachable for the
            same purpose.

quote end.

I've written a small extension that implement this, it also create
a sysctl "net.inet.tcp.icmp_admin_prohib_like_rst" to control if
this new behaviour is activated.

When it's activated (set to 1) we'll treat a ICMP administratively
prohibited message (icmp type 3 code 9, 10 and 13) for a TCP
sessions, as if we recived a TCP RST, but only if the TCP session
is in SYN_SENT state.

The reason for only reacting when in SYN_SENT state, is that this
will solve the problem, and at the same time minimize the risk of
this being abused.

I suggest that we enable this new behaviour by default, but it
would be a change of current behaviour, so if people prefer to
leave it disabled by default, at least for now, this would be ok
for me, the attached diff actually have the sysctl set to 0 by
default.

PR:		23086
Submitted by:	Jesper Skriver <jesper@skriver.dk>
2000-12-16 19:42:06 +00:00
Jayanth Vijayaraghavan
e7f3269307 When a connection is being dropped due to a listen queue overflow,
delete the cloned route that is associated with the connection.
This does not exhaust the routing table memory when the system
is under a SYN flood attack. The route entry is not deleted if there
is any prior information cached in it.

Reviewed by: Peter Wemm,asmodai
2000-07-21 23:26:37 +00:00
Sheldon Hearn
571214d4fe Fix a comment which was broken in rev 1.36.
PR:		19947
Submitted by:	Tetsuya Isaki <isaki@net.ipc.hiroshima-u.ac.jp>
2000-07-18 16:43:29 +00:00
Jake Burkholder
e39756439c Back out the previous change to the queue(3) interface.
It was not discussed and should probably not happen.

Requested by:		msmith and others
2000-05-26 02:09:24 +00:00
Jake Burkholder
740a1973a6 Change the way that the queue(3) structures are declared; don't assume that
the type argument to *_HEAD and *_ENTRY is a struct.

Suggested by:	phk
Reviewed by:	phk
Approved by:	mdodd
2000-05-23 20:41:01 +00:00
Jonathan Lemon
46f5848237 Implement TCP NewReno, as documented in RFC 2582. This allows
better recovery for multiple packet losses in a single window.
The algorithm can be toggled via the sysctl net.inet.tcp.newreno,
which defaults to "on".

Submitted by:  Jayanth Vijayaraghavan <jayanth@yahoo-inc.com>
2000-05-06 03:31:09 +00:00
Yoshinobu Inoue
fb59c426ff tcp updates to support IPv6.
also a small patch to sys/nfs/nfs_socket.c, as max_hdr size change.

Reviewed by: freebsd-arch, cvs-committers
Obtained from: KAME project
2000-01-09 19:17:30 +00:00
Peter Wemm
664a31e496 Change #ifdef KERNEL to #ifdef _KERNEL in the public headers. "KERNEL"
is an application space macro and the applications are supposed to be free
to use it as they please (but cannot).  This is consistant with the other
BSD's who made this change quite some time ago.  More commits to come.
1999-12-29 04:46:21 +00:00
Yoshinobu Inoue
6a800098cc IPSEC support in the kernel.
pr_input() routines prototype is also changed to support IPSEC and IPV6
chained protocol headers.

Reviewed by: freebsd-arch, cvs-committers
Obtained from: KAME project
1999-12-22 19:13:38 +00:00
Yoshinobu Inoue
76429de41a KAME related header files additions and merges.
(only those which don't affect c source files so much)

Reviewed by: cvs-committers
Obtained from: KAME project
1999-11-05 14:41:39 +00:00
Jonathan Lemon
9b8b58e033 Restructure TCP timeout handling:
- eliminate the fast/slow timeout lists for TCP and instead use a
    callout entry for each timer.
  - increase the TCP timer granularity to HZ
  - implement "bad retransmit" recovery, as presented in
    "On Estimating End-to-End Network Path Properties", by Allman and Paxson.

Submitted by:	jlemon, wollmann
1999-08-30 21:17:07 +00:00
Peter Wemm
c3aac50f28 $Id$ -> $FreeBSD$ 1999-08-28 01:08:13 +00:00
Doug Rabson
ce02431ffa * Change sysctl from using linker_set to construct its tree using SLISTs.
This makes it possible to change the sysctl tree at runtime.

* Change KLD to find and register any sysctl nodes contained in the loaded
  file and to unregister them when the file is unloaded.

Reviewed by: Archie Cobbs <archie@whistle.com>,
	Peter Wemm <peter@netplex.com.au> (well they looked at it anyway)
1999-02-16 10:49:55 +00:00
Bill Fenner
b0acefa8d4 Add a flag, passed to pru_send routines, PRUS_MORETOCOME. This
flag means that there is more data to be put into the socket buffer.
Use it in TCP to reduce the interaction between mbuf sizes and the
Nagle algorithm.

Based on:	"Justin C. Walker" <justin@apple.com>'s description of Apple's
		fix for this problem.
1999-01-20 17:32:01 +00:00
Doug Rabson
6effc71332 Re-implement tcp and ip fragment reassembly to not store pointers in the
ip header which can't work on alpha since pointers are too big.

Reviewed by: Garrett Wollman <wollman@khavrinen.lcs.mit.edu>
1998-08-24 07:47:39 +00:00
Garrett Wollman
cfe8b629f1 Yow! Completely change the way socket options are handled, eliminating
another specialized mbuf type in the process.  Also clean up some
of the cruft surrounding IPFW, multicast routing, RSVP, and other
ill-explored corners.
1998-08-23 03:07:17 +00:00
Bruce Evans
07a4df4fee Declare tcp_seq and tcp_cc as fixed-size types. Half fixed type
mismatches exposed by this (the prototype for tcp_respond() didn't
match the  function definition lexically, and still depends on a
gcc feature to match if ints have more than 32 bits).
1998-07-13 11:09:52 +00:00
John Hay
a910fdcb88 Only make struct xtcpcb visable if _NETINET_IN_PCB_H_ and _SYS_SOCKETVAR_H_
are defined.
Reviewed by:	bde
1998-06-27 07:30:45 +00:00
Garrett Wollman
98271db4d5 Convert socket structures to be type-stable and add a version number.
Define a parameter which indicates the maximum number of sockets in a
system, and use this to size the zone allocators used for sockets and
for certain PCBs.

Convert PF_LOCAL PCB structures to be type-stable and add a version number.

Define an external format for infomation about socket structures and use
it in several places.

Define a mechanism to get all PF_LOCAL and PF_INET PCB lists through
sysctl(3) without blocking network interrupts for an unreasonable
length of time.  This probably still has some bugs and/or race
conditions, but it seems to work well enough on my machines.

It is now possible for `netstat' to get almost all of its information
via the sysctl(3) interface rather than reading kmem (changes to follow).
1998-05-15 20:11:40 +00:00
David Greenman
552b7df4c1 Ensure that TCP_REXMTVAL doesn't return a value less than t_rttmin. This
is believed to have been broken with the Brakmo/Peterson srtt
calculation changes. The result of this bug is that TCP connections
could time out extremely quickly (in 12 seconds).
Also backed out jdp's partial fix for this problem in rev 1.17 of
tcp_timer.c as it is obsoleted by this commit.
Bug was pointed out by Kevin Lehey <kml@roller.nas.nasa.gov>.

PR:	6068
1998-04-24 09:25:39 +00:00
Poul-Henning Kamp
8e5db87cdb Remove the last traces of TUBA.
Inspired by:	PR kern/3317
1998-04-06 06:52:47 +00:00
David Greenman
f498eeeead Changes to support the addition of a new sysctl variable:
net.inet.tcp.delack_enabled
Which defaults to 1 and can be set to 0 to disable TCP delayed-ack
processing (i.e. all acks are immediate).
1998-02-26 05:25:39 +00:00
David Greenman
c3229e05a3 Improved connection establishment performance by doing local port lookups via
a hashed port list. In the new scheme, in_pcblookup() goes away and is
replaced by a new routine, in_pcblookup_local() for doing the local port
check. Note that this implementation is space inefficient in that the PCB
struct is now too large to fit into 128 bytes. I might deal with this in the
future by using the new zone allocator, but I wanted these changes to be
extensively tested in their current form first.

Also:
1) Fixed off-by-one errors in the port lookup loops in in_pcbbind().
2) Got rid of some unneeded rehashing. Adding a new routine, in_pcbinshash()
   to do the initialial hash insertion.
3) Renamed in_pcblookuphash() to in_pcblookup_hash() for easier readability.
4) Added a new routine, in_pcbremlists() to remove the PCB from the various
   hash lists.
5) Added/deleted comments where appropriate.
6) Removed unnecessary splnet() locking. In general, the PCB functions should
   be called at splnet()...there are unfortunately a few exceptions, however.
7) Reorganized a few structs for better cache line behavior.
8) Killed my TCP_ACK_HACK kludge. It may come back in a different form in
   the future, however.

These changes have been tested on wcarchive for more than a month. In tests
done here, connection establishment overhead is reduced by more than 50
times, thus getting rid of one of the major networking scalability problems.

Still to do: make tcp_fastimo/tcp_slowtimo scale well for systems with a
large number of connections. tcp_fastimo is easy; tcp_slowtimo is difficult.

WARNING: Anything that knows about inpcb and tcpcb structs will have to be
         recompiled; at the very least, this includes netstat(1).
1998-01-27 09:15:13 +00:00
Garrett Wollman
a29f300e80 The long-awaited mega-massive-network-code- cleanup. Part I.
This commit includes the following changes:
1) Old-style (pr_usrreq()) protocols are no longer supported, the compatibility
glue for them is deleted, and the kernel will panic on boot if any are compiled
in.

2) Certain protocol entry points are modified to take a process structure,
so they they can easily tell whether or not it is possible to sleep, and
also to access credentials.

3) SS_PRIV is no more, and with it goes the SO_PRIVSTATE setsockopt()
call.  Protocols should use the process pointer they are now passed.

4) The PF_LOCAL and PF_ROUTE families have been updated to use the new
style, as has the `raw' skeleton family.

5) PF_LOCAL sockets now obey the process's umask when creating a socket
in the filesystem.

As a result, LINT is now broken.  I'm hoping that some enterprising hacker
with a bit more time will either make the broken bits work (should be
easy for netipx) or dike them out.
1997-04-27 20:01:29 +00:00