Commit Graph

55 Commits

Author SHA1 Message Date
Joe Marcus Clarke
b07fbc17e9 Add Cisco Skinny Station protocol support to libalias, natd, and ppp.
Skinny is the protocol used by Cisco IP phones to talk to Cisco Call
Managers.  With this code, one can use a Cisco IP phone behind a FreeBSD
NAT gateway.

Currently, having the Call Manager behind the NAT gateway is not supported.
More information on enabling Skinny support in libalias, natd, and ppp
can be found in those applications' manpages.

PR:		55843
Reviewed by:	ru
Approved by:	ru
MFC after:	30 days
2003-09-23 07:41:55 +00:00
Ruslan Ermilov
8e75a37bb0 Fixed -Wpointer-arith warning.
Submitted by:	Stefan Farfeleder
PR:		bin/56653
2003-09-09 23:50:57 +00:00
Ruslan Ermilov
234dfc904a A new API function PacketAliasRedirectDynamic() can be used
to mark a fully specified static link as dynamic; i.e. make
it a one-time link.
2003-06-01 23:15:00 +00:00
Ruslan Ermilov
f1a529f3da Make the PacketAliasSetAddress() function call optional. If it
is not called, and no static rules match an outgoing packet, the
latter retains its source IP address.  This is in support of the
"static NAT only" mode.
2003-06-01 22:49:59 +00:00
Luigi Rizzo
90780c4b05 Move IPFW2 definition before including ip_fw.h
Make indentation of new parts consistent with the style used for this file.
2002-07-18 05:18:41 +00:00
Luigi Rizzo
b3063f064c Fix a bug caused by dereferencing an invalid pointer when
no punch_fw was used.
Fix another couple of bugs which prevented rules from being
installed properly.

On passing, use IPFW2 instead of NEW_IPFW to compile the new code,
and slightly simplify the instruction generation code.
2002-07-08 22:57:35 +00:00
Brian Somers
27cc91fbf8 Remove trailing whitespace 2002-07-01 11:19:40 +00:00
Luigi Rizzo
9758b77ff1 The new ipfw code.
This code makes use of variable-size kernel representation of rules
(exactly the same concept of BPF instructions, as used in the BSDI's
firewall), which makes firewall operation a lot faster, and the
code more readable and easier to extend and debug.

The interface with the rest of the system is unchanged, as witnessed
by this commit. The only extra kernel files that I am touching
are if_fw.h and ip_dummynet.c, which is quite tied to ipfw. In
userland I only had to touch those programs which manipulate the
internal representation of firewall rules).

The code is almost entirely new (and I believe I have written the
vast majority of those sections which were taken from the former
ip_fw.c), so rather than modifying the old ip_fw.c I decided to
create a new file, sys/netinet/ip_fw2.c .  Same for the user
interface, which is in sbin/ipfw/ipfw2.c (it still compiles to
/sbin/ipfw).  The old files are still there, and will be removed
in due time.

I have not renamed the header file because it would have required
touching a one-line change to a number of kernel files.

In terms of user interface, the new "ipfw" is supposed to accepts
the old syntax for ipfw rules (and produce the same output with
"ipfw show". Only a couple of the old options (out of some 30 of
them) has not been implemented, but they will be soon.

On the other hand, the new code has some very powerful extensions.
First, you can put "or" connectives between match fields (and soon
also between options), and write things like

ipfw add allow ip from { 1.2.3.4/27 or 5.6.7.8/30 } 10-23,25,1024-3000 to any

This should make rulesets slightly more compact (and lines longer!),
by condensing 2 or more of the old rules into single ones.

Also, as an example of how easy the rules can be extended, I have
implemented an 'address set' match pattern, where you can specify
an IP address in a format like this:

        10.20.30.0/26{18,44,33,22,9}

which will match the set of hosts listed in braces belonging to the
subnet 10.20.30.0/26 . The match is done using a bitmap, so it is
essentially a constant time operation requiring a handful of CPU
instructions (and a very small amount of memmory -- for a full /24
subnet, the instruction only consumes 40 bytes).

Again, in this commit I have focused on functionality and tried
to minimize changes to the other parts of the system. Some performance
improvement can be achieved with minor changes to the interface of
ip_fw_chk_t. This will be done later when this code is settled.

The code is meant to compile unmodified on RELENG_4 (once the
PACKET_TAG_* changes have been merged), for this reason
you will see #ifdef __FreeBSD_version in a couple of places.
This should minimize errors when (hopefully soon) it will be time
to do the MFC.
2002-06-27 23:02:18 +00:00
Brian Somers
e83aaae350 cmott@scientech.com -> cm@linktel.net
Requested by:	Charles Mott <cmott@scientech.com>
2001-11-03 11:34:09 +00:00
Matthew Dillon
e2505aa676 Add __FBSDID's to libalias 2001-09-30 21:03:33 +00:00
Brian Somers
f68e0a68d8 Make the copyright consistent.
Previously approved by:	Charles Mott <cmott@scientech.com>
2001-08-20 22:57:33 +00:00
Brian Somers
f987e1bd0f Add BSD-style copyright headers
Approved by: Charles Mott <cmott@scientech.com>
2001-06-04 15:09:51 +00:00
Ruslan Ermilov
79ec1c507a Add an integer field to keep protocol-specific flags with links.
For FTP control connection, keep the CRLF end-of-line termination
status in there.

Fixed the bug when the first FTP command in a session was ignored.

PR:		24048
MFC after:	1 week
2001-05-30 14:24:35 +00:00
Brian Somers
71593f95e0 Make header files conform to style(9).
Reviewed by (*): bde

(*) alias_local.h only got a cursory glance.
2001-03-25 12:05:10 +00:00
Ruslan Ermilov
642cd09fb3 Added boolean argument to link searching functions, indicating
whether they should create a link if lookup has failed or not.
2000-10-30 17:24:12 +00:00
Ruslan Ermilov
03453c5e87 A significant rewrite of PPTP aliasing code.
PPTP links are no longer dropped by simple (and inappropriate in this
case) "inactivity timeout" procedure, only when requested through the
control connection.

It is now possible to have multiple PPTP servers running behind NAT.
Just redirect the incoming TCP traffic to port 1723, everything else
is done transparently.

Problems were reported and the fix was tested by:
		Michael Adler <Michael.Adler@compaq.com>,
		David Andersen <dga@lcs.mit.edu>
2000-10-30 12:39:41 +00:00
Ruslan Ermilov
f136389613 A failure to allocate memory for auxiliary TCP data is now fatal.
This fixes a null pointer dereference problem that is unlikely to
happen in normal circumstances.
2000-10-19 10:44:44 +00:00
Ruslan Ermilov
305d10699e Create aliasing links for incoming ICMP echo/timestamp requests.
This makes outgoing ICMP echo/timestamp replies to be de-aliased
with the right source IP, not exactly the primary aliasing IP.
2000-08-31 12:47:57 +00:00
Ruslan Ermilov
a05f06d79f Fixed PunchFW code segmentation violation bug.
Reported by:	Christian Schade <chris@cube.sax.de>
2000-08-14 15:24:47 +00:00
Ruslan Ermilov
b834663f47 Use queue(3) LIST_* macros for doubly-linked lists. 2000-08-14 14:18:16 +00:00
Archie Cobbs
642e43b39b Add address translation support for RTSP/RTP used by RealPlayer and
Quicktime streaming media applications.

Add a BUGS section to the man page.

Submitted by:	Erik Salander <erik@whistle.com>
2000-07-26 23:15:46 +00:00
Ruslan Ermilov
36e6576b44 Fixed PunchFWHole():
- ipfw always rejected rule with `neither in nor out' diagnostics.
- number of src/dst ports was not set properly.
2000-06-27 14:56:07 +00:00
Ruslan Ermilov
d15583713a - Removed PacketAliasPptp() API function.
- SHLIB_MAJOR++.
2000-06-20 13:07:52 +00:00
Ruslan Ermilov
55a39fc5a2 Added true support for PPTP aliasing. Some nice features include:
- Multiple PPTP clients behind NAT to the same or different servers.

- Single PPTP server behind NAT -- you just need to redirect TCP
  port 1723 to a local machine.  Multiple servers behind NAT is
  possible but would require a simple API change.

- No API changes!

For more information on how this works see comments at the start of
the alias_pptp.c.

PacketAliasPptp() is no longer necessary and will be removed soon.

Submitted by:	Erik Salander <erik@whistle.com>
Reviewed by:	ru
Rewritten by:	ru
Reviewed by:	Erik Salander <erik@whistle.com>
2000-06-20 11:41:48 +00:00
Ruslan Ermilov
7652512976 - Added support for passive mode FTP by aliasing 227 replies.
It does mean that it is now possible to run passive-mode FTP
  server behind NAT.

- SECURITY: FTP aliasing engine now ensures that:
  o the segment preceding a PORT/227 segment terminates with a \r\n;
  o the IP address in the PORT/227 matches the source IP address of
    the packet;
  o the port number in the PORT command or 277 reply is greater than
    or equal to 1024.

Submitted by:	Erik Salander <erik@whistle.com>
Reviewed by:	ru
2000-06-14 16:09:35 +00:00
Brian Somers
151682eadc Revert the default behaviour for incoming connections so
that they (once again) go to the target machine rather than
the alias address.

PR:		18354
Submitted by:	ru
2000-05-11 07:52:21 +00:00
Ruslan Ermilov
8060760500 Replace PacketAliasRedirectPptp() (which had nothing specific
to PPTP) with more generic PacketAliasRedirectProto().

Major number is not bumped because it is believed that noone
has started using PacketAliasRedirectPptp() yet.
2000-04-28 13:44:49 +00:00
Ruslan Ermilov
6d20a77450 Load Sharing using IP Network Address Translation (RFC 2391, LSNAT).
LSNAT links are first created by either PacketAliasRedirectPort() or
PacketAliasRedirectAddress() and then set up by one or more calls to
PacketAliasAddServer().
2000-04-27 17:37:03 +00:00
Ruslan Ermilov
483d2f2296 Add support for multiple PPTP sessions:
- new API function: PacketAliasRedirectPptp()
- new mode bit: PKT_ALIAS_DENY_PPTP

Please see manual page for details.
2000-04-18 10:18:21 +00:00
Ruslan Ermilov
b5e819ec23 Apply TCP_EXPIRE_CONNECTED (86400 seconds) timeout only to established
connections, after SYN packets were seen from both ends.  Before this,
it would get applied right after the first SYN packet was seen (either
from client or server).  With broken TCP connection attempts, when the
remote end does not respond with SYNACK nor with RST, this resulted in
having a useless (ie, no actual TCP connection associated with it) TCP
link with 86400 seconds TTL, wasting system memory.  With high rate of
such broken connection attempts (for example, remote end simply blocks
these connection attempts with ipfw(8) without sending RST back), this
could result in a denial-of-service.

PR:		bin/17963
2000-04-14 15:34:55 +00:00
Ruslan Ermilov
f167e54283 Make partially specified permanent links without `dst_addr'
but with `dst_port' work for outgoing packets.

This case was not handled properly when I first fixed this
in revision 1.17.

This change is also required for the upcoming improved PPTP
support patches -- that is how I found the problem.

Before this change:

# natd -v -a aliasIP \
  -redirect_port tcp localIP:localPORT publicIP:publicPORT 0:remotePORT

Out [TCP]  [TCP] localIP:localPORT -> remoteIP:remotePORT aliased to
           [TCP] aliasIP:localPORT -> remoteIP:remotePORT

After this change:

# natd -v -a aliasIP \
  -redirect_port tcp localIP:localPORT publicIP:publicPORT 0:remotePORT

Out [TCP]  [TCP] localIP:localPORT -> remoteIP:remotePORT aliased to
           [TCP] publicIP:publicPORT -> remoteIP:remotePORT
2000-04-12 18:44:50 +00:00
Brian Somers
5dd44916b7 Allow PacketAliasSetTarget() to be passed the following:
INADDR_NONE:   Incoming packets go to the alias address (the default)
  INADDR_ANY:    Incoming packets are not NAT'd (direct access to the
                 internal network from outside)
  anything else: Incoming packets go to the specified address

Change a few inaddr::s_addr == 0 to inaddr::s_addr == INADDR_ANY
while I'm there.
2000-03-31 20:36:29 +00:00
Brian Somers
1c4e6d2544 When an incoming packet is received that is not specifically
redirected and when no target address has been specified, NAT
the destination address to the alias address rather than
allowing people direct access to your internal network from
outside.
2000-03-31 14:03:37 +00:00
Brian Somers
9da582e318 Make _FindLinkIn() static and only define GetDestPort when
NO_FW_PUNCH isn't defined.
2000-03-19 09:11:05 +00:00
Archie Cobbs
a9405f0edb Fix a '&&' that should have been a '&'.
Submitted by:	Erik Salander <erik@whistle.com>
1999-12-10 20:04:53 +00:00
Ruslan Ermilov
838d9af2c8 Properly handle the case when either the aliasing or source address of
the link are equal to the default aliasing address.  Do not zero them!

This will fix the problem with non-working links added with the source
and/or aliasing address equal to the default aliasing address, but the
default aliasing address is set later, after the link has been set up,
like both natd(8) and ppp(8) do (for objective reasons).

Reviewed by:	Brian Somers <brian@FreeBSD.org>,
		Eivind Eklund <eivind@FreeBSD.org>,
		Charles Mott <cmott@srv.net>
1999-09-27 08:40:36 +00:00
Ruslan Ermilov
bd3ed4542d ReLink() partial links in FindLinkOut() in the same manner as we do it
in FindLinkIn().  This will make TcpMonitorIn()/TcpMonitorOut() happy.

Reviewed by:	eivind
1999-09-22 13:22:26 +00:00
Ruslan Ermilov
f3baa77e5e Restore previous version of FindLinkIn().
Instead, natd(8) should be fixed to call PacketAliasSetAddress()
as part of initialization, as required by libalias(3).
1999-09-21 14:44:32 +00:00
Ruslan Ermilov
02136bf8b0 - Make partially specified permanent links (without `dst_addr' and/or
`dst_port') work for outgoing packets.

- Make permanent links whose `alias_addr' matches the primary aliasing
  address `aliasAddress' work for incoming packets.

- Typo fixes.

Reviewed by:	brian, eivind
1999-09-21 08:40:20 +00:00
Brian Somers
32277d8b6d sys/errno.h -> errno.h 1999-09-21 01:26:49 +00:00
Bill Fumerola
a5a388c7ab Add $FreeBSD$ and spell Eklund properly.
Approved by:	brian (well, he approved adding $Id$)
1999-08-29 23:17:04 +00:00
Eivind Eklund
5164f52665 Make incoming packets work as keepalives, too. This should fix problems
for some games.

Notified of problem by:	tim@turbinegames.com
1999-05-20 20:20:24 +00:00
Brian Somers
4c32f5d217 Remove all diagnostics to stdout/stderr with #ifdef DEBUG
Statify functions in alias_nbt.c
1999-03-09 23:44:00 +00:00
Brian Somers
164928d385 Document PacketAliasPptp() and allow it to be disabled
by passing INADDR_NONE.
1999-03-07 18:13:23 +00:00
Brian Somers
7d96f4efd2 Version 3.0: January 1, 1999
- Transparent proxying support added.
    - PPTP redirecting support added based on patches
      contributed by Dru Nelson <dnelson@redwoodsoft.com>.

Submitted by: Charles Mott <cmott@srv.net>
1999-02-27 02:16:01 +00:00
Brian Somers
a2743da670 If we can't open alias.log, don't try to write to the
resulting NULL FILE *.
PR:	9403
1999-01-10 02:05:13 +00:00
Brian Somers
9feab75ab7 o Support a compile-time -DNO_FW_PUNCH for portability
(and those of us that don't want the functionality).
o Don't assume sizeof(long) == 4.
Ok'd by: Charles Mott <cmott@srv.net>
1998-04-19 21:42:07 +00:00
Brian Somers
0ffaca1078 1) in CleanupAliasData, don't nullify entry in linkTableOut
since there might be permanent entries still left after
   calls to DeleteLink (it will be nullified by DeleteLink
   if all entries are deleted, won't it ?)

2) in PacketAliasSetAddress, set the aliasing address
   even when PKT_ALIAS_RESET_ON_ADDR_CHANGE is in effect.
   Just don't clean up links in this case.

Submitted by: Ari Suutari <ari@suutari.iki.fi>
         via: Charles Mott <cmott@srv.net>
PR: 5041
1998-02-27 23:07:07 +00:00
Eivind Eklund
58ba5f4a30 Remove use of <osreldate.h>.
Screwed up by: myself
1998-01-11 18:34:38 +00:00
Alexander Langer
1e73fe2ae8 Sync with ipfw interface change: fw_pts is now part of a union (a
necessary evil due to the 108 byte setsockopt() limit).
1998-01-10 16:14:18 +00:00