Commit Graph

237 Commits

Author SHA1 Message Date
Crist J. Clark
010dabb047 Add a 'verrevpath' option that verifies the interface that a packet
comes in on is the same interface that we would route out of to get to
the packet's source address. Essentially automates an anti-spoofing
check using the information in the routing table.

Experimental. The usage and rule format for the feature may still be
subject to change.
2003-03-15 01:13:00 +00:00
Maxim Konovalov
45f6135194 o Partially revert rev. 1.103, fix 'ipfw show': dynamically adjust a
width of fields for packets and bytes counters.

PR:		bin/47196
Reviewed by:	-audit
Not objected by: luigi, des

o Use %llu instead of deprecated %qu convert specification for ipfw
packets and bytes counters.

Noted by:	des
MFC after:	1 month
2003-03-13 10:51:53 +00:00
Ruslan Ermilov
8b5381e069 /modules is gone long ago, use the safe equivalents. 2003-03-03 22:46:36 +00:00
Christian Brueffer
16b3d3546d Correct examples for stateful inspection
PR:		47817
Submitted by:	Simon L.Nielsen <simon@nitro.dk>
Reviewed by:	ceri, luigi
2003-02-04 01:33:25 +00:00
Matthew Dillon
6690be9efa It turns out that we do not need to add a new ioctl to unbreak a
default-to-deny firewall.  Simply turning off IPFW via a preexisting
sysctl does the job.  To make it more apparent (since nobody picked up
on this in a week's worth of flames), the boolean sysctl's have been
integrated into the /sbin/ipfw command set in an obvious and straightforward
manner.  For example, you can now do 'ipfw disable firewall' or
'ipfw enable firewall'.  This is far easier to remember then the
net.inet.ip.fw.enable sysctl.

Reviewed by:	imp
MFC after:	3 days
2003-01-12 03:31:10 +00:00
Giorgos Keramidas
c41a3921ef Fix a reference to the order of SYNOPSIS lines.
Submitted by:	Olivier Cherrier <Olivier.Cherrier@cediti.be>
		on freebsd-net
MFC after:	3 days
2003-01-05 00:09:23 +00:00
Jens Schweikhardt
9d5abbddbf Correct typos, mostly s/ a / an / where appropriate. Some whitespace cleanup,
especially in troff files.
2003-01-01 18:49:04 +00:00
Kelly Yancey
ca6e3cb0e4 Make preprocessor support more generic by passing all command-line options
after -p except for the last (the ruleset file to process) to the
preprocessor for interpretation.  This allows command-line options besides
-U and -D to be passed to cpp(1) and m4(1) as well as making it easier to
use other preprocessors.

Sponsored By:	NTT Multimedia Communications Labs
MFC after:	1 week
2002-12-23 20:08:21 +00:00
Giorgos Keramidas
3d2209ae92 Align timestamps when -t is used in ipfw and ipfw2.
PR:		kern/44843
Approved by:	re (jhb)
2002-11-26 22:53:14 +00:00
Luigi Rizzo
12b5dc6a39 Fix a kernel panic with rules of the type
prob 0.5 pipe NN ....

due to the generation of an invalid ipfw instruction sequence.
No ABI change, but you need to upgrade /sbin/ipfw to generate the
correct code.

Approved by: re
2002-11-26 19:58:12 +00:00
Luigi Rizzo
99652d0eb2 Update documentation to match the behaviour of ipfw with respect
to net.inet.ip.fw.one_pass.
Add to notes to explain the exact behaviour of "prob xxx" and "log"
options.

Virtually approved by: re (mentioned in rev.1.19 of ip_fw2.c)
2002-11-26 19:51:40 +00:00
Maxim Konovalov
a54587ad70 Kill EOL whitespaces, style(9) fix. 2002-11-06 15:09:34 +00:00
Maxim Konovalov
d6abaeebeb Fix UID/GID options parsing.
PR:		bin/42579
Submitted by:	Belousov Oleg <oleg@belousov.com>
Approved by:	luigi
MFC after:	2 weeks
2002-11-06 14:57:18 +00:00
Luigi Rizzo
4d5fe224c6 Misc fixes from Chris Pepper, plus additional explainations on
dummynet operation.

MFC after: 3 days
2002-10-28 07:03:56 +00:00
Maxime Henrion
7c697970f4 Fix ipfw2 panics on 64-bit platforms.
Quoting luigi:

In order to make the userland code fully 64-bit clean it may
be necessary to commit other changes that may or may not cause
a minor change in the ABI.

Reviewed by:	luigi
2002-10-24 18:04:44 +00:00
Sean Chittenden
927a76bb5e Increase the max dummynet hash size from 1024 to 65536. Default is still
1024.

Silence on:	-net, -ipfw 4weeks+
Reviewed by:	dd
Approved by:	knu (mentor)
MFC after:	3 weeks
2002-10-12 07:45:23 +00:00
Maxim Konovalov
3ec6f79c1e Do not dump core on 'ipfw add unreach': handling null strings in
fill_reject_code(). Please note ipfw/ipfw2.c is not affected.

PR:		bin/42304
Submitted by:	Andy@wantpackets.com
MFC after:	1 day
2002-09-25 11:22:36 +00:00
Maxim Konovalov
8bca894718 o Fix a typo.
o Remove EOL spaces.

Submitted by:	Harold Gutch <logix@foobar.franken.de> (typo patch)
Approved by:	luigi
MFC after:	3 days
2002-09-22 11:30:51 +00:00
Luigi Rizzo
4f531a5368 Store the port number in "fwd" rules in host format, same as ipfw1
has always done.

Technically, this is the wrong format, but it reduces the diffs in
-stable. Someday, when we get rid of ipfw1, I will put the port number
in the proper format both in kernel and userland.

MFC after: 3 days
(with re@ permission)
2002-09-12 00:45:32 +00:00
Marc Fonvieille
eea54e1396 Typo: s/o packet/on packet/
PR:		docs/42543
Submitted by:	Michael Lyngbøl <lyngbol@bifrost.lyngbol.dk>
2002-09-08 09:01:08 +00:00
Tom Rhodes
ce66ddb763 s/filesystem/file system/g as discussed on -developers 2002-08-21 18:11:48 +00:00
Luigi Rizzo
f0ac20f7d2 Whoops, the manpage lied... ipfw2 has always accepted addr:mask
specifications.
2002-08-21 05:57:41 +00:00
Luigi Rizzo
5a155b405e One more (hopefully the last one) step in cleaning up the syntax,
following Julian's good suggestion: since you can specify any match
pattern as an option, rules now have the following format:

	[<proto> from <src> to <dst>] [options]

i.e. the first part is now entirely optional (and left there just
for compatibility with ipfw1 rulesets).

Add a "-c" flag to show/list rules in the compact form
(i.e. without the "ip from any to any" part) when possible.
The default is to include it so that scripts processing ipfw's
canonical output will still work.
Note that as part of this cleanup (and to remove ambiguity), MAC
fields now can only be specified in the options part.

Update the manpage to reflect the syntax.

Clarify the behaviour when a match is attempted on fields which
are not present in the packet, e.g. port numbers on non TCP/UDP
packets, and the "not" operator is specified. E.g.

	ipfw add allow not src-port 80

will match also ICMP packets because they do not have port numbers, so
"src-port 80" will fail and "not src-port 80" will succeed. For such
cases it is advised to insert further options to prevent undesired results
(e.g. in the case above, "ipfw add allow proto tcp not src-port 80").

We definitely need to rewrite the parser using lex and yacc!
2002-08-19 12:36:54 +00:00
Luigi Rizzo
e706181ba6 Major cleanup of the parser and printing routines in an attempt to
render the syntax less ambiguous.

Now rules can be in one of these two forms

	<action> <protocol> from <src> to <dst> [options]
	<action> MAC dst-mac src-mac mac-type [options]

however you can now specify MAC and IP header fields as options e.g.

	ipfw add allow all from any to any mac-type arp
	ipfw add allow all from any to any { dst-ip me or src-ip me }

which makes complex expressions a lot easier to write and parse.
The "all from any to any" part is there just for backward compatibility.

Manpage updated accordingly.
2002-08-19 04:52:15 +00:00
Luigi Rizzo
654399a477 Complete list of differences between ipfw1 and ipfw2. 2002-08-16 14:27:22 +00:00
Luigi Rizzo
99e5e64504 sys/netinet/ip_fw2.c:
Implement the M_SKIP_FIREWALL bit in m_flags to avoid loops
    for firewall-generated packets (the constant has to go in sys/mbuf.h).

    Better comments on keepalive generation, and enforce dyn_rst_lifetime
    and dyn_fin_lifetime to be less than dyn_keepalive_period.

    Enforce limits (up to 64k) on the number of dynamic buckets, and
    retry allocation with smaller sizes.

    Raise default number of dynamic rules to 4096.

    Improved handling of set of rules -- now you can atomically
    enable/disable multiple sets, move rules from one set to another,
    and swap sets.

sbin/ipfw/ipfw2.c:

    userland support for "noerror" pipe attribute.

    userland support for sets of rules.

    minor improvements on rule parsing and printing.

sbin/ipfw/ipfw.8:

    more documentation on ipfw2 extensions, differences from ipfw1
    (so we can use the same manpage for both), stateful rules,
    and some additional examples.
    Feedback and more examples needed here.
2002-08-16 10:31:47 +00:00
Luigi Rizzo
8ed2d7497b Fix one parsing bug introduced by last commit, and correct parsing
and printing of or-blocks in address, ports and options lists.
2002-08-10 15:10:15 +00:00
Luigi Rizzo
ac4ed01f56 Major revision of the ipfw manpage, trying to make it up-to-date
with ipfw2 extensions and give examples of use of the new features.

This is just a preliminary commit, where i simply added the basic
syntax for the extensions, and clean up the page (e.g. by listing
things in alphabetical rather than random order).
I would appreciate feedback and possible corrections/extensions
by interested parties.

Still missing are a more detailed description of stateful rules
(with keepalives), interaction with of stateful rules and natd (don't do
that!), examples of use with the recently introduced rule sets.

There is an issue related to the MFC: RELENG_4 still has ipfw as a
default, and ipfw2 is optional. We have two options here: MFC this
page as ipfw(8) adding a large number of "SORRY NOT IN IPFW" notes,
or create a new ipfw2(8) manpage just for -stable users.  I am all
for the first approach, but of course am listening to your comments.
2002-08-10 15:04:40 +00:00
Luigi Rizzo
43405724ec One bugfix and one new feature.
The bugfix (ipfw2.c) makes the handling of port numbers with
a dash in the name, e.g. ftp-data, consistent with old ipfw:
use \\ before the - to consider it as part of the name and not
a range separator.

The new feature (all this description will go in the manpage):

each rule now belongs to one of 32 different sets, which can
be optionally specified in the following form:

	ipfw add 100 set 23 allow ip from any to any

If "set N" is not specified, the rule belongs to set 0.

Individual sets can be disabled, enabled, and deleted with the commands:

	ipfw disable set N
	ipfw enable set N
	ipfw delete set N

Enabling/disabling of a set is atomic. Rules belonging to a disabled
set are skipped during packet matching, and they are not listed
unless you use the '-S' flag in the show/list commands.
Note that dynamic rules, once created, are always active until
they expire or their parent rule is deleted.
Set 31 is reserved for the default rule and cannot be disabled.

All sets are enabled by default. The enable/disable status of the sets
can be shown with the command

	ipfw show sets

Hopefully, this feature will make life easier to those who want to
have atomic ruleset addition/deletion/tests. Examples:

To add a set of rules atomically:

	ipfw disable set 18
	ipfw add ... set 18 ...		# repeat as needed
	ipfw enable set 18

To delete a set of rules atomically

	ipfw disable set 18
	ipfw delete set 18
	ipfw enable set 18

To test a ruleset and disable it and regain control if something
goes wrong:

	ipfw disable set 18
	ipfw add ... set 18 ...         # repeat as needed
	ipfw enable set 18 ; echo "done "; sleep 30 && ipfw disable set 18

    here if everything goes well, you press control-C before
    the "sleep" terminates, and your ruleset will be left
    active. Otherwise, e.g. if you cannot access your box,
    the ruleset will be disabled after the sleep terminates.

I think there is only one more thing that one might want, namely
a command to assign all rules in set X to set Y, so one can
test a ruleset using the above mechanisms, and once it is
considered acceptable, make it part of an existing ruleset.
2002-08-10 04:37:32 +00:00
Luigi Rizzo
b985a624a3 Fix generation of check-state rules, which i broke in last commit. 2002-08-04 05:16:19 +00:00
Luigi Rizzo
6136001211 Forgot this one: properly initialize an address set when the set
size is less than 32 bits (/28 mask or more).
Also remove a debugging fprintf().
2002-07-31 22:42:08 +00:00
Luigi Rizzo
52bc23ab8a Two bugfixes:
+ the header file contains two different opcodes (O_IPOPTS and O_IPOPT)
    for what is the same thing, and sure enough i used one in the kernel
    and the other one in userland. Be consistent!

  + "keep-state" and "limit" must be the last match pattern in a rule,
    so no matter how you enter them move them to the end of the rule.
2002-07-31 22:31:47 +00:00
Sheldon Hearn
b7563355f3 Add SEE ALSO references to papers handling RED. 2002-07-25 09:37:11 +00:00
Luigi Rizzo
0a7197a83c A bunch of minor fixes:
* accept "icmptype" as an alias for "icmptypes";
* remove an extra whitespace after "log" rules;
* print correctly the "limit" masks;
* correct a typo in parsing dummynet arguments (this caused a coredump);
* do not allow specifying both "check-state" and "limit", they are
  (and have always been) mutually exclusive;
* remove an extra print of the rule before installing it;
* make stdout buffered -- otherwise, if you log its output with syslog,
  you will see one entry for each printf(). Rather unpleasant.
2002-07-13 15:57:23 +00:00
Bruce Evans
bb89ddf57b Uncommented WARNS=0. ipfw2.c is full of printf format errors that are
fatal on alphas.

Fixed setting of WARNS.  WARNS should never be set unconditionally, since
this breaks testing of different WARNS values by setting it at a higher
level (e.g., on the command line).
2002-07-11 17:33:37 +00:00
Bruce Evans
006559a292 Fixed some world breakage caused by not updating clients when <timeconv.h>
was split off from <time.h>.  This became fatal here when -Werror was
reenabled.
2002-07-08 19:49:52 +00:00
Philippe Charnier
e1205e80e5 The .Nm utility 2002-07-06 19:34:18 +00:00
Luigi Rizzo
5e43aef891 Implement the last 2-3 missing instructions for ipfw,
now it should support all the instructions of the old ipfw.

Fix some bugs in the user interface, /sbin/ipfw.

Please check this code against your rulesets, so i can fix the
remaining bugs (if any, i think they will be mostly in /sbin/ipfw).

Once we have done a bit of testing, this code is ready to be MFC'ed,
together with a bunch of other changes (glue to ipfw, and also the
removal of some global variables) which have been in -current for
a couple of weeks now.

MFC after: 7 days
2002-07-05 22:43:06 +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
Luigi Rizzo
ed81aa8668 Handle symbolic names for common ethernet types (ip, arp etc.)
Remove custom definitions (IP_FW_TCPF_SYN etc.) of TCP header flags
which are the same as the original ones (TH_SYN etc.)
2002-05-13 10:19:59 +00:00
Luigi Rizzo
d61ee39cd5 Main functional change is the implementation of matching of MAC header
fields as discussed in the commit to ip_fw.c:1.186

On top of this, a ton of non functional changes to clean up the code,
write functions to replace sections of code that were replicated
multiple times (e.g. the printing or matching of flags and options),
splitting long sections of inlined code into separate functions,
and the like.

I have tested the code quite a bit, but some typos (using one variable
in place of another) might have escaped.

The "embedded manpage" is a bit inconsistent, but i am leaving fixing
it for later. The current format makes no sense, it is over 40 lines
long and practically unreadable. We can either split it into sections
( ipfw -h options  , ipfw -h pipe , ipfw -h queue ...)
or remove it altogether and refer to the manpage.
2002-05-12 20:52:21 +00:00
Luigi Rizzo
4f1e3c3c4c Fix a couple of problems which could cause panics at runtime:
+ setting a bandwidth too large for a pipe (above 2Gbit/s) could
   cause the internal representation (which is int) to wrap to a
   negative number, causing an infinite loop in the kernel;

 + (see PR bin/35628): when configuring RED parameters for a queue,
   the values are not passed to the kernel resulting in panics at
   runtime (part of the problem here is also that the kernel does
   not check for valid parameters being passed, but this will be
   fixed in a separate commit).

These are both critical fixes which need to be merged into 4.6-RELEASE.

MFC after: 1 day
2002-05-05 21:34:10 +00:00
Crist J. Clark
0f56b10c4b Enlighten those who read the FINE POINTS of the documentation a bit
more on how ipfw(8) deals with tiny fragments. While we're at it, add
a quick log message to even let people know we dropped a packet. (Note
that the second FINE POINT is somewhat redundant given the first, but
since the code is there, leave the docs for it.)

MFC after:	1 day
2002-05-01 06:29:16 +00:00
Matthew Dillon
170ac683f2 I've been meaning to do this for a while. Add an underscore to the
time_to_xxx() and xxx_to_time() functions.  e.g. _time_to_xxx()
instead of time_to_xxx(), to make it more obvious that these are
stopgap functions & placemarkers and not meant to create a defacto
standard.  They will eventually be replaced when a real standard
comes out of committee.
2002-01-19 23:20:02 +00:00
Ruslan Ermilov
6bfa982817 mdoc(7) police: tidy up the markup in revision 1.96. 2002-01-10 15:41:06 +00:00
Robert Watson
e036a58dab o Note that packets diverted using a 'divert' socket, and then
reinserted by a userland process, will lose a number of packet
  attributes, including their source interface.  This may affect
  the behavior of later rules, and while not strictly a BUG, may
  cause unexpected behavior if not clearly documented.  A similar
  note for natd(8) might be desirable.
2002-01-03 01:00:23 +00:00
Yaroslav Tykhiy
c1201321e4 Move the discussion of how many times a packet will pass through
ipfirewall(4) to the IMPLEMENTATION NOTES section because it
considers kernel internals and may confuse newbies if placed
at the very beginning of the manpage (where it used to be previously.)

Not objected by:	luigi
2002-01-02 20:48:21 +00:00
Yaroslav Tykhiy
5b20d7fa96 Clarify the "show" ipfw(8) command.
PR:		docs/31263
Permitted by:	luigi
2002-01-02 20:16:15 +00:00
Yaroslav Tykhiy
a66dbdf331 Fix a typo: wierd -> weird 2002-01-02 19:46:14 +00:00
Julian Elischer
116f97b066 Fix documentation to match reality 2001-12-28 22:24:26 +00:00