Allow set 31 to be used for rules other than 65535.
Set 31 is still special because rules belonging to it are not deleted
by the "ipfw flush" command, but must be deleted explicitly with
"ipfw delete set 31" or by individual rule numbers.
This implement a flexible form of "persistent rules" which you might
want to have available even after an "ipfw flush".
Note that this change does not violate POLA, because you could not
use set 31 in a ruleset before this change.
Suggested by: Paul Richards
introduced in the latest commits).
Also:
* update the 'ipfw -h' output;
* allow rules of the form "100 add allow ..." i.e. with the index first.
(requested by Paul Richards). This was an undocumented ipfw1 behaviour,
and it is left undocumented.
and minor code cleanups.
* make the code compile with WARNS=5 (at least on i386), mostly
by adding 'const' specifier and replacing "void *" with "char *"
in places where pointer arithmetic was used.
This also spotted a few places where invalid tests (e.g. uint < 0)
were used.
* support ranges in "list" and "show" commands. Now you can say
ipfw show 100-1000 4000-8000
which is very convenient when you have large rulesets.
* implement comments in ipfw commands. These are implemented in the
kernel as O_NOP commands (which always match) whose body contains
the comment string. In userland, a comment is a C++-style comment:
ipfw add allow ip from me to any // i can talk to everybody
The choice of '//' versus '#' is somewhat arbitrary, but because
the preprocessor/readfile part of ipfw used to strip away '#',
I did not want to change this behaviour.
If a rule only contains a comment
ipfw add 1000 // this rule is just a comment
then it is stored as a 'count' rule (this is also to remind
the user that scanning through a rule is expensive).
* improve handling of flags (still to be completed).
ipfw_main() was written thinking of 'one rule per ipfw invocation',
and so flags are set and never cleared. With readfile/preprocessor
support, this changes and certain flags should be reset on each
line. For the time being, only fix handling of '-a' which
differentiates the "list" and "show" commands.
* rework the preprocessor support -- ipfw_main() already had most
of the parsing code, so i have moved in there the only missing
bit (stripping away '#' and comments) and removed the parsing
from ipfw_readfile().
Also, add some more options (such as -c, -N, -S) to the readfile
section.
MFC after: 3 days
spaces and comma-separated lists of arguments;
* reword the description of address specifications, to include
previous and current changes for address sets and lists;
* document the new '-n' flag.
* update the section on differences between ipfw1 and ipfw2
(this is becoming boring!)
MFC after: 3 days
* Make the addr-set size optional (defaults to /24)
You can now write 1.2.3.0/24{56-80} or 1.2.3.0{56-80}
Also make the parser more strict.
* Support a new format for the list of addresses:
1.2.3.4,5.6.7.8/30,9.10.11.12/22,12.12.12.13, ...
which exploits the new capabilities of O_IP_SRC_MASK/O_IP_DST_MASK
* Allow spaces after commas to make lists of addresses more readable.
1.2.3.4, 5.6.7.8/30, 9.10.11.12/22, 12.12.12.13, ...
* ipfw will now accept full commands as a single argument and strip
extra leading/trailing whitespace as below:
ipfw "-q add allow ip from 1.2.3.4 to 5.6.7.8, 9.10.11.23 "
This should help in moving the body of ipfw into a library
that user programs can invoke.
* Cleanup some comments and data structures.
* Do not print rule counters for dynamic rules with ipfw -d list
(PR 51182)
* Improve 'ipfw -h' output (PR 46785)
* Add a '-n' flag to test the syntax of commands without actually
calling [gs]etsockopt() (PR 44238)
* Support the '-n' flag also with the preprocessors;
Manpage commit to follow.
MFC after: 3 days
Should work with both regular and fast ipsec (mutually exclusive).
See manpage for more details.
Submitted by: Ari Suutari (ari.suutari@syncrontech.com)
Revised by: sam
MFC after: 1 week
1.2.3.4/24{5,6,7,10-20,60-90}
for set of ip addresses.
Previously you needed to specify every address in the range, which
was unconvenient and lead to very long lines.
Internally the set is still stored in the same way, just the
input and output routines are modified.
Manpage update still missing.
Perhaps a similar preprocessing step would be useful for port ranges.
MFC after: 3 days
"ipid" options. This feature has been requested by several users.
On passing, fix some minor bugs in the parser. This change is fully
backward compatible so if you have an old /sbin/ipfw and a new
kernel you are not in trouble (but you need to update /sbin/ipfw
if you want to use the new features).
Document the changes in the manpage.
Now you can write things like
ipfw add skipto 1000 iplen 0-500
which some people were asking to give preferential treatment to
short packets.
The 'MFC after' is just set as a reminder, because I still need
to merge the Alpha/Sparc64 fixes for ipfw2 (which unfortunately
change the size of certain kernel structures; not that it matters
a lot since ipfw2 is entirely optional and not the default...)
PR: bin/48015
MFC after: 1 week
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.
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
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
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
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
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)
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
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)
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!
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.
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.
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.
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.
