Later when introducing per chain rule caches, nft_rule_list_get() will
be removed. But nftnl_rule_list_cb() which it uses will be reused to
update each chain's rule cache from inside nftnl_chain_list_get(), so
move both into position.
Signed-off-by: Phil Sutter <phil@nwl.cc> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Phil Sutter [Thu, 20 Dec 2018 15:09:08 +0000 (16:09 +0100)]
nft: Simplify per table chain cache update
Previously, each table's chain cache was potentially unallocated until
nftnl_chain_list_cb() saw a chain for it. This means such callback had to
check the chain_cache pointer for each chain belonging to that table.
In addition to the above, nft_chain_list_get() had to cover for the
possibility that a given table didn't have any chains at all in kernel,
so check requested table's chain cache once more and allocate it if
NULL.
Instead, simply iterate over all tables and preallocate their chain
caches prior to requesting the chain list from kernel. The only caveat
is to flush the chain cache completely before retrying in case of EINTR.
Signed-off-by: Phil Sutter <phil@nwl.cc> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Phil Sutter [Thu, 20 Dec 2018 15:09:07 +0000 (16:09 +0100)]
nft: Reduce indenting level in flush_chain_cache()
Instead of doing all in one go, make two separate decisions:
1) If table has no chain cache, either continue or return depending on
whether we're flushing for a specific table.
2) With chain cache present, flushing strategy once more depends on
whether we're flushing for a specific table: If given, just remove
all rules and return. If not, free the cache and set to NULL (so that
it will be repopulated later), then continue the loop.
Signed-off-by: Phil Sutter <phil@nwl.cc> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Phil Sutter [Thu, 20 Dec 2018 15:09:05 +0000 (16:09 +0100)]
nft: Review is_*_compatible() routines
- Call to nft_table_builtin_find() in nft_is_table_compatible() is not
needed, as it is repeated in the latter call to nft_chain_list_get()
by nft_are_chains_compatible().
- Turn nft_is_chain_compatible(), nft_is_rule_compatible() and
nft_is_expr_compatible() into callbacks for use with respective
foreach functions.
- nft_are_chains_compatible() is not needed anymore due to foreach
function use.
Signed-off-by: Phil Sutter <phil@nwl.cc> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Phil Sutter [Thu, 20 Dec 2018 15:09:04 +0000 (16:09 +0100)]
xtables-restore: Review chain handling
There is no need to "delete" (actually, remove from cache) a chain if
noflush wasn't given: While handling the corresponding table line,
'table_flush' callback has already taken care of that.
This .chain_del indirection is not required since d1eb4d587297
("iptables-compat: chains are purge out already from table flush").
Streamlining the code further, move syntax checks to the top. If these
concede, there are three cases to distinguish:
A) Given chain name matches a builtin one in current table, so assume it
exists already and just set policy and counters.
B) Noflush was given and the (custom) chain exists already, flush it.
C) Custom chain was either flushed (noflush not given) or didn't exist
before, create it.
Signed-off-by: Phil Sutter <phil@nwl.cc> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Phil Sutter [Thu, 20 Dec 2018 15:09:03 +0000 (16:09 +0100)]
nft: Review unclear return points
When converting to per table chain caches, these two error returns were
marked for review but apparently forgotten. Make sure error condition is
propagated when returning at those points.
Fixes: c58ecf9f8bcb7 ("xtables: Introduce per table chain caches") Signed-off-by: Phil Sutter <phil@nwl.cc> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Phil Sutter [Thu, 20 Dec 2018 15:09:02 +0000 (16:09 +0100)]
nft: Simplify nftnl_rule_list_chain_save()
Since there are per table chain caches, The chain list passed to that
function is comprised of chains belonging to the right table only.
Therefore the table name check can safely be skipped.
Signed-off-by: Phil Sutter <phil@nwl.cc> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Baruch Siach [Sun, 2 Dec 2018 16:56:34 +0000 (18:56 +0200)]
include: extend the headers conflict workaround to in6.h
Commit 8d9d7e4b9ef ("include: fix build with kernel headers before 4.2")
introduced a kernel/user headers conflict workaround that allows build
of iptables with kernel headers older than 4.2. This minor extension
allows build with kernel headers older than 3.12, which is the version
that introduced explicit IP headers synchronization.
Fixes: 8d9d7e4b9ef4 ("include: fix build with kernel headers before 4.2") Cc: Florian Westphal <fw@strlen.de> Signed-off-by: Baruch Siach <baruch@tkos.co.il> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Older versions of iptables allowed for negative realm values by accident
(they would be cast to unsigned). While this was clearly a bug, document
the fixed behaviour.
Signed-off-by: Phil Sutter <phil@nwl.cc> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Phil Sutter [Tue, 27 Nov 2018 19:07:11 +0000 (20:07 +0100)]
xtables: Don't use native nftables comments
The problem with converting libxt_comment into nftables comment is that
rules change when parsing from kernel due to comment match being moved
to the end of the match list. And since match ordering matters, the rule
may not be found anymore when checking or deleting. Apart from that,
iptables-nft didn't support multiple comments per rule anymore. This is
a compatibility issue without technical reason.
Leave conversion from nftables comment to libxt_comment in place so we
don't break running systems during an update.
Signed-off-by: Phil Sutter <phil@nwl.cc> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Baruch Siach [Sat, 17 Nov 2018 20:20:08 +0000 (22:20 +0200)]
xtables-monitor: fix build with musl libc
Commit 7c8791edac3 ("xtables-monitor: fix build with older glibc")
changed the code to use GNU style tcphdr fields. Unfortunately, musl
libc requires _GNU_SOURCE definition to expose these fields.
Fix the following build failure:
xtables-monitor.c: In function ‘trace_print_packet’:
xtables-monitor.c:406:43: error: ‘const struct tcphdr’ has no member named ‘source’
printf("SPORT=%d DPORT=%d ", ntohs(tcph->source), ntohs(tcph->dest));
^~
xtables-monitor.c:406:64: error: ‘const struct tcphdr’ has no member named ‘dest’
printf("SPORT=%d DPORT=%d ", ntohs(tcph->source), ntohs(tcph->dest));
^~
...
Baruch Siach [Fri, 16 Nov 2018 07:30:33 +0000 (09:30 +0200)]
include: fix build with kernel headers before 4.2
Commit 672accf1530 (include: update kernel netfilter header files)
updated linux/netfilter.h and brought with it the update from kernel
commit a263653ed798 (netfilter: don't pull include/linux/netfilter.h
from netns headers). This triggers conflict of headers that is fixed in
kernel commit 279c6c7fa64f (api: fix compatibility of linux/in.h with
netinet/in.h) included in kernel version 4.2. For earlier kernel headers
we need a workaround that prevents the headers conflict.
Fixes the following build failure:
In file included from .../sysroot/usr/include/netinet/ip.h:25:0,
from ../include/libiptc/ipt_kernel_headers.h:8,
from ../include/libiptc/libiptc.h:6,
from libip4tc.c:29:
.../sysroot/usr/include/linux/in.h:26:3: error: redeclaration of enumerator ‘IPPROTO_IP’
IPPROTO_IP = 0, /* Dummy protocol for TCP */
^
.../sysroot/usr/include/netinet/in.h:33:5: note: previous definition of ‘IPPROTO_IP’ was here
IPPROTO_IP = 0, /* Dummy protocol for TCP. */
^~~~~~~~~~
Phil Sutter [Thu, 15 Nov 2018 13:53:02 +0000 (14:53 +0100)]
xtables: Introduce per table chain caches
Being able to omit the previously obligatory table name check when
iterating over the chain cache might help restore performance with large
rulesets in xtables-save and -restore.
There is one subtle quirk in the code: flush_chain_cache() did free the
global chain cache if not called with a table name but didn't if a table
name was given even if it emptied the chain cache. In other places,
chain_cache being non-NULL prevented a cache update from happening, so
this patch establishes the same behaviour (for each individual chain
cache) since otherwise unexpected cache updates lead to weird problems.
Signed-off-by: Phil Sutter <phil@nwl.cc> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Baruch Siach [Fri, 16 Nov 2018 05:23:32 +0000 (07:23 +0200)]
xtables-monitor: fix build with older glibc
glibc older than 2.19 only expose BSD style fields of struct tcphdr when
_BSD_SOURCE is define. Current glibc however, warn that _BSD_SOURCE is
deprecated. Migrate to the GNU style of tcphdr fields to make the code
compatible with any glibc version.
Fix the following build failure:
xtables-monitor.c: In function 'trace_print_packet':
xtables-monitor.c:406:43: error: 'const struct tcphdr' has no member named 'th_sport'
printf("SPORT=%d DPORT=%d ", ntohs(tcph->th_sport), ntohs(tcph->th_dport));
^
xtables-monitor.c:406:66: error: 'const struct tcphdr' has no member named 'th_dport'
printf("SPORT=%d DPORT=%d ", ntohs(tcph->th_sport), ntohs(tcph->th_dport));
^
...
Adam Gołębiowski [Wed, 14 Nov 2018 06:35:28 +0000 (07:35 +0100)]
extensions: format-security fixes in libip[6]t_icmp
commit 61d6c3834de3 ("xtables: add 'printf' attribute to xlate_add")
introduced support for gcc feature to check format string against passed
argument. This commit adds missing bits to extenstions's libipt_icmp.c
and libip6t_icmp6.c that were causing build to fail.
Fixes: 61d6c3834de3 ("xtables: add 'printf' attribute to xlate_add") Signed-off-by: Adam Gołębiowski <adamg@pld-linux.org> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Build with musl libc fails because of conflicting struct ethhdr
definitions:
In file included from .../sysroot/usr/include/net/ethernet.h:10:0,
from ../iptables/nft-bridge.h:8,
from libebt_vlan.c:18:
.../sysroot/usr/include/netinet/if_ether.h:107:8: error: redefinition of ‘struct ethhdr’
struct ethhdr {
^~~~~~
In file included from libebt_vlan.c:16:0:
.../sysroot/usr/include/linux/if_ether.h:160:8: note: originally defined here
struct ethhdr {
^~~~~~
Include the userspace header first for the definition suppression logic
to do the right thing.
Signed-off-by: Baruch Siach <baruch@tkos.co.il> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Phil Sutter [Wed, 19 Sep 2018 14:25:58 +0000 (16:25 +0200)]
ip6tables-save: Merge into iptables-save.c
Both implementations were very similar already. Differences were mostly
in which libiptc functions were called. Therefore introduce struct
iptables_save_cb to point to the right functions for each variant.
Signed-off-by: Phil Sutter <phil@nwl.cc> Signed-off-by: Florian Westphal <fw@strlen.de>
Florian Westphal [Mon, 12 Nov 2018 13:40:41 +0000 (14:40 +0100)]
xtables: add 'printf' attribute to xlate_add
This allows gcc to check format string vs. passed arguments.
Fix the fallout from this as well, typical warning produced is:
libebt_mark_m.c:112:28: warning: format '%x' expects argument of type 'unsigned int', but argument 3 has type 'long unsigned int' [-Wformat=]
xt_xlate_add(xl, "and 0x%x %s0 ", info->mask, ...
~^ ~~~~~~~~~~
so add the required casts or fixup format strings as needed.
libxt_conntrack also passed an unneeded argument (port), so remove that.
In arptables-classic, the kernel will add dev->addr_len to the
arp header base address to obtain the correct location, but we cannot
do this in nf_tables, at least not at this time (we need a fixed offset
value).
but if user did not provide "--h-length 6" argument, then this won't
work even for ethernet, as the payload expression will be told to load
the first 4 bytes of arp header source mac address (sender hw address).
Fix this by pre-initialising arhlen to 6.
We also need to set up arhrd. Otherwise, src/dst mac can't be used:
arptables -A INPUT -i lo --destination-mac 11:22:33:44:55:66
arptables v1.8.1 (nf_tables): RULE_APPEND failed (Invalid argument): rule in chain INPUT
This means that matching won't work for AX25, NETROM etc, however,
arptables "classic" can't parse non-ethernet addresses, and makes
ETH_ALEN assumptions in several spots, so this should be fine from
compatibility point of view.
1. check both address and mask, not just first byte of mac
2. use add_addr() for this so mask is also handled via bitwise expr.
3. use the correct offsets.
4. add dissector so we can reverse translate the payload expressions
generated for this.
arptables classic doesn't have arptables-save, it only has a perl
script that attempts to emulate iptables-save. It supports no options,
and thus has no way to dump counters. Add -c option, like iptables to
enable this.
Florian Westphal [Mon, 12 Nov 2018 11:49:11 +0000 (12:49 +0100)]
ebtables: use extrapositioned negation consistently
in the iptables universe, we enforce extrapositioned negation:
! -i foo
"-i ! foo" is not even supported anymore.
At least make sure that ebtables prints the former syntax everywhere as
well so we don't have a mix of both ways.
Parsing of --option ! 42 will still work for backwards compat reasons.
iptables-tests: do not append xtables-multi to external commands
Lines starting by @ can be used to invoke an external command of any
kind. Do not add xtables-multi here since we may want to execute a
non-iptables command.
-j CONTINUE can be added, but it can't be removed:
extensions/libebt_standard.t: ERROR: line 5 (cannot find: ebtables -I INPUT -d de:ad:be:ef:00:00 -j CONTINUE)
This problem stems from silly ambiguity in ebtables-nft vs. iptables.
In iptables, you can do
iptables -A INPUT
(no -j)
in ebtables, you can do either
ebtables -A INPUT
or
ebtables -A INPUT -j CONTINUE
both are *supposed* to be the same (and they do the same even
in ebtables-nft on netlink side).
However, the temprary binary representation within ebtables-nft is not
the same: when parsing -j CONTINUE, we add a standard target, then omit
it later in _add_target().
When translating netlink representation to ebt binary one,
we do not add a standard target and instead just print '-j CONTINUE'
when listing rules.
So when doing
-I INPUT -j CONTINUE
-D INPUT -j CONTINUE
the -D operation fails because it has a standard target in the binary
representation, whereas the rule we obtained from translating
nftables netlink back to ebtables' binary represenation doesn't.
Phil Sutter [Wed, 31 Oct 2018 19:13:34 +0000 (20:13 +0100)]
xtables: Fix for matching rules with wildcard interfaces
Due to xtables_parse_interface() and parse_ifname() being misaligned
regarding interface mask setting, rules containing a wildcard interface
added with iptables-nft could neither be checked nor deleted.
As suggested, introduce extensions/iptables.t to hold checks for
built-in selectors. This file is picked up by iptables-test.py as-is.
The only limitation is that iptables is being used for it, so no
ip6tables-specific things can be tested with it (for now).
Signed-off-by: Phil Sutter <phil@nwl.cc> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Phil Sutter [Thu, 11 Oct 2018 11:30:38 +0000 (13:30 +0200)]
xtables: Remove target_maxnamelen field
This is a partial revert of commit 9f075031a1973 ("Combine
parse_target() and command_jump() implementations"): Upstream prefers to
reduce max chain name length of arptables by two characters instead of
the introduced struct xtables_globals field which requires to bump
library API version.
Fixes: 9f075031a1973 ("Combine parse_target() and command_jump() implementations") Signed-off-by: Phil Sutter <phil@nwl.cc> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Chenbo Feng [Tue, 2 Oct 2018 01:23:07 +0000 (18:23 -0700)]
extensions: libxt_quota: Allow setting the remaining quota
The current xt_quota module cannot track the current remaining quota
of a specific rule. Everytime an unrelated rule is updated in the same
iptables table, the quota will be reset. This is not a very useful
function for iptables that get changed at run time. This patch fixes the
above problem by adding a new field in the struct that records the
current remaining quota.
Fixed a print out bug in verbose print out wrt. inversion.
Signed-off-by: Chenbo Feng <fengc@google.com> Suggested-by: Maciej Żenczykowski <maze@google.com> Reviewed-by: Maciej Żenczykowski <maze@google.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Phil Sutter [Mon, 24 Sep 2018 17:25:24 +0000 (19:25 +0200)]
Combine parse_target() and command_jump() implementations
Merge these two functions from xtables, iptables, ip6tables and
arptables. Both functions were basically identical in the first three,
only the last one required a bit more attention.
To eliminate access to 'invflags' in variant-specific location, move the
call to set_option() into callers. This is actually consistent with
parsing of other options in them.
As with command_match(), use xt_params instead of the different
*_globals objects to refer to 'opts' and 'orig_opts'.
It was necessary to rename parse_target() as it otherwise clashes with a
static function of same name in libxt_SET.
In arptables, the maximum allowed target name is a bit larger, so
introduce xtables_globals.target_maxnamelen defining the value. It is
used in the shared xt_parse_target() implementation.
Implementation of command_jump() in arptables diverted from the others
for no obvious reason. The call to parse_target() was done outside of it
and a pointer to cs->arp was passed but not used inside.
Signed-off-by: Phil Sutter <phil@nwl.cc> Signed-off-by: Florian Westphal <fw@strlen.de>
Phil Sutter [Mon, 24 Sep 2018 17:25:23 +0000 (19:25 +0200)]
Combine command_match() implementations
This merges the basically identical implementations of command_match()
from xtables, iptables and ip6tables into one. The only required
adjustment was to make use of xt_params instead of the different
*_globals objects.
Signed-off-by: Phil Sutter <phil@nwl.cc> Signed-off-by: Florian Westphal <fw@strlen.de>
Phil Sutter [Mon, 24 Sep 2018 17:25:22 +0000 (19:25 +0200)]
libiptc: NULL-terminate errorname
In struct chain_head, field 'name' is of size TABLE_MAXNAMELEN, hence
copying its content into 'error_name' field of struct xt_error_target
which is two bytes shorter may overflow. Make sure this doesn't happen
by using strncpy() and set the last byte to zero.
Signed-off-by: Phil Sutter <phil@nwl.cc> Signed-off-by: Florian Westphal <fw@strlen.de>
Phil Sutter [Wed, 19 Sep 2018 13:17:07 +0000 (15:17 +0200)]
arptables: Fix incorrect strcmp() in nft_arp_rule_find()
Since nft_arp_rule_to_cs() may not set cs->jumpto, later call to
strcmp() may be passed a NULL pointer. Therefore check if the pointer is
valid before doing so.
Signed-off-by: Phil Sutter <phil@nwl.cc> Signed-off-by: Florian Westphal <fw@strlen.de>
Phil Sutter [Wed, 19 Sep 2018 13:17:06 +0000 (15:17 +0200)]
xtables: Don't read garbage in nft_ipv4_parse_payload()
The problem here is that get_frag() does not set 'inv' in any case, so
when later checking its value, garbage may be read. Sanitize this case
by setting 'inv' to false before calling get_frag().
Signed-off-by: Phil Sutter <phil@nwl.cc> Signed-off-by: Florian Westphal <fw@strlen.de>
Phil Sutter [Wed, 19 Sep 2018 13:17:05 +0000 (15:17 +0200)]
libxtables: Use posix_spawn() instead of vfork()
According to covscan, vfork() may lead to a deadlock in the parent
process. It suggests to use posix_spawn() instead. Since the latter
combines vfork() and exec() calls, use it for xtables_insmod().
Signed-off-by: Phil Sutter <phil@nwl.cc> Signed-off-by: Florian Westphal <fw@strlen.de>
Phil Sutter [Wed, 19 Sep 2018 13:17:03 +0000 (15:17 +0200)]
extensions: libebt_ip{, 6}: Drop pointless error checking
Since info->protocol is of type __u8, its value will never become -1.
Apart from that, xtables_parse_protocol() calls xt_params->exit_err() in
case of error, so this code is dead anyway.
Signed-off-by: Phil Sutter <phil@nwl.cc> Signed-off-by: Florian Westphal <fw@strlen.de>
Phil Sutter [Wed, 19 Sep 2018 13:17:00 +0000 (15:17 +0200)]
iptables: Use print_ifaces() from xtables
Move the function to xshared.c for common use between legacy and xtables
sources. While being at it, silence a covscan warning triggered by that
function as it couldn't verify input buffers won't exceed IFNAMSIZ.
Therefore use snprintf() when writing to the local buffer.
Signed-off-by: Phil Sutter <phil@nwl.cc> Signed-off-by: Florian Westphal <fw@strlen.de>