The function signatures for Xtables extensions have grown over time.
It involves a lot of typing/replication, and also a bit of stack space
even if they are not used. Realize an NFWS2008 idea and pack them into
structs. The skb remains outside of the struct so gcc can continue to
apply its optimizations.
This patch does this for match extensions' match functions.
A few ambiguities have also been addressed. The "offset" parameter for
example has been renamed to "fragoff" (there are so many different
offsets already) and "protoff" to "thoff" (there is more than just one
protocol here, so clarify).
Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
It used to be that {ip,ip6,etc}_tables called extension->checkentry
themselves, but this can be moved into the xtables core.
Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Rule dumping is performed in two steps: first userspace gets the
ruleset size using getsockopt(SO_GET_INFO) and allocates memory,
then it calls getsockopt(SO_GET_ENTRIES) to actually dump the
ruleset. When another process changes the ruleset in between the
sizes from the first getsockopt call doesn't match anymore and
the kernel aborts. Unfortunately it returns EAGAIN, as for multiple
other possible errors, so userspace can't distinguish this case
from real errors.
Return EAGAIN so userspace can retry the operation.
Fixes (with current iptables SVN version) netfilter bugzilla #104.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Introduce per-sock inlines: sock_net(), sock_net_set()
and per-inet_timewait_sock inlines: twsk_net(), twsk_net_set().
Without CONFIG_NET_NS, no namespace other than &init_net exists.
Let's explicitly define them to help compiler optimizations.
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
__FUNCTION__ is gcc-specific, use __func__
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
CHECK net/ipv4/netfilter/ip_tables.c
net/ipv4/netfilter/ip_tables.c:1453:8: warning: incorrect type in argument 3 (different signedness)
net/ipv4/netfilter/ip_tables.c:1453:8: expected int *size
net/ipv4/netfilter/ip_tables.c:1453:8: got unsigned int [usertype] *size
net/ipv4/netfilter/ip_tables.c:1458:44: warning: incorrect type in argument 3 (different signedness)
net/ipv4/netfilter/ip_tables.c:1458:44: expected int *size
net/ipv4/netfilter/ip_tables.c:1458:44: got unsigned int [usertype] *size
net/ipv4/netfilter/ip_tables.c:1603:2: warning: incorrect type in argument 2 (different signedness)
net/ipv4/netfilter/ip_tables.c:1603:2: expected unsigned int *i
net/ipv4/netfilter/ip_tables.c:1603:2: got int *<noident>
net/ipv4/netfilter/ip_tables.c:1627:8: warning: incorrect type in argument 3 (different signedness)
net/ipv4/netfilter/ip_tables.c:1627:8: expected int *size
net/ipv4/netfilter/ip_tables.c:1627:8: got unsigned int *size
net/ipv4/netfilter/ip_tables.c:1634:40: warning: incorrect type in argument 3 (different signedness)
net/ipv4/netfilter/ip_tables.c:1634:40: expected int *size
net/ipv4/netfilter/ip_tables.c:1634:40: got unsigned int *size
net/ipv4/netfilter/ip_tables.c:1653:8: warning: incorrect type in argument 5 (different signedness)
net/ipv4/netfilter/ip_tables.c:1653:8: expected unsigned int *i
net/ipv4/netfilter/ip_tables.c:1653:8: got int *<noident>
net/ipv4/netfilter/ip_tables.c:1666:2: warning: incorrect type in argument 2 (different signedness)
net/ipv4/netfilter/ip_tables.c:1666:2: expected unsigned int *i
net/ipv4/netfilter/ip_tables.c:1666:2: got int *<noident>
CHECK net/ipv4/netfilter/arp_tables.c
net/ipv4/netfilter/arp_tables.c:1285:40: warning: incorrect type in argument 3 (different signedness)
net/ipv4/netfilter/arp_tables.c:1285:40: expected int *size
net/ipv4/netfilter/arp_tables.c:1285:40: got unsigned int *size
net/ipv4/netfilter/arp_tables.c:1543:44: warning: incorrect type in argument 3 (different signedness)
net/ipv4/netfilter/arp_tables.c:1543:44: expected int *size
net/ipv4/netfilter/arp_tables.c:1543:44: got unsigned int [usertype] *size
CHECK net/ipv6/netfilter/ip6_tables.c
net/ipv6/netfilter/ip6_tables.c:1481:8: warning: incorrect type in argument 3 (different signedness)
net/ipv6/netfilter/ip6_tables.c:1481:8: expected int *size
net/ipv6/netfilter/ip6_tables.c:1481:8: got unsigned int [usertype] *size
net/ipv6/netfilter/ip6_tables.c:1486:44: warning: incorrect type in argument 3 (different signedness)
net/ipv6/netfilter/ip6_tables.c:1486:44: expected int *size
net/ipv6/netfilter/ip6_tables.c:1486:44: got unsigned int [usertype] *size
net/ipv6/netfilter/ip6_tables.c:1631:2: warning: incorrect type in argument 2 (different signedness)
net/ipv6/netfilter/ip6_tables.c:1631:2: expected unsigned int *i
net/ipv6/netfilter/ip6_tables.c:1631:2: got int *<noident>
net/ipv6/netfilter/ip6_tables.c:1655:8: warning: incorrect type in argument 3 (different signedness)
net/ipv6/netfilter/ip6_tables.c:1655:8: expected int *size
net/ipv6/netfilter/ip6_tables.c:1655:8: got unsigned int *size
net/ipv6/netfilter/ip6_tables.c:1662:40: warning: incorrect type in argument 3 (different signedness)
net/ipv6/netfilter/ip6_tables.c:1662:40: expected int *size
net/ipv6/netfilter/ip6_tables.c:1662:40: got unsigned int *size
net/ipv6/netfilter/ip6_tables.c:1680:8: warning: incorrect type in argument 5 (different signedness)
net/ipv6/netfilter/ip6_tables.c:1680:8: expected unsigned int *i
net/ipv6/netfilter/ip6_tables.c:1680:8: got int *<noident>
net/ipv6/netfilter/ip6_tables.c:1693:2: warning: incorrect type in argument 2 (different signedness)
net/ipv6/netfilter/ip6_tables.c:1693:2: expected unsigned int *i
net/ipv6/netfilter/ip6_tables.c:1693:2: got int *<noident>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
When number of entries exceeds number of initial entries, foo-tables code
will pin table module. But during table unregister on netns stop,
that additional pin was forgotten.
Signed-off-by: Alexey Dobriyan <adobriyan@sw.ru>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
* Propagate netns from userspace down to xt_find_table_lock()
* Register ip6 tables in netns (modules still use init_net)
Signed-off-by: Alexey Dobriyan <adobriyan@sw.ru>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Typical table module registers xt_table structure (i.e. packet_filter)
and link it to list during it. We can't use one template for it because
corresponding list_head will become corrupted. We also can't unregister
with template because it wasn't changed at all and thus doesn't know in
which list it is.
So, we duplicate template at the very first step of table registration.
Table modules will save it for use during unregistration time and actual
filtering.
Do it at once to not screw bisection.
P.S.: renaming i.e. packet_filter => __packet_filter is temporary until
full netnsization of table modules is done.
Signed-off-by: Alexey Dobriyan <adobriyan@sw.ru>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
In fact all we want is per-netns set of rules, however doing that will
unnecessary complicate routines such as ipt_hook()/ipt_do_table, so
make full xt_table array per-netns.
Every user stubbed with init_net for a while.
Signed-off-by: Alexey Dobriyan <adobriyan@sw.ru>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Switch from 0/-E to ptr/PTR_ERR convention.
Signed-off-by: Alexey Dobriyan <adobriyan@sw.ru>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Jan Engelhardt <jengelh@computergmbh.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch removes inlines except those which are used
by packet matching code and thus are performance-critical.
Before:
$ size */*/*/ip*tables*.o
text data bss dec hex filename
6402 500 16 6918 1b06 net/ipv4/netfilter/ip_tables.o
7130 500 16 7646 1dde net/ipv6/netfilter/ip6_tables.o
After:
$ size */*/*/ip*tables*.o
text data bss dec hex filename
6307 500 16 6823 1aa7 net/ipv4/netfilter/ip_tables.o
7010 500 16 7526 1d66 net/ipv6/netfilter/ip6_tables.o
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Parenthesize macro parameters.
Signed-off-by: Jan Engelhardt <jengelh@computergmbh.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Use raw_smp_processor_id() in do_add_counters() as in ip_tables.c.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fix leakage of local variable on stack. This already got fixed in
ip_tables silently by the compat patches.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Reformat ip_tables.c and ip6_tables.c in order to eliminate non-functional
differences and minimize diff output.
This allows to get a view of the real differences using:
sed -e 's/IP6T/IPT/g' \
-e 's/IP6/IP/g' \
-e 's/INET6/INET/g' \
-e 's/ip6t/ipt/g' \
-e 's/ip6/ip/g' \
-e 's/ipv6/ip/g' \
-e 's/icmp6/icmp/g' \
net/ipv6/netfilter/ip6_tables.c | \
diff -wup /dev/stdin net/ipv4/netfilter/ip_tables.c
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Resync get_entries() with ip_tables.c by moving the checks from the
setsockopt handler to the function itself.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
More resyncing with ip_tables.c as preparation for compat support.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Consistently use vmalloc_node for all counter allocations.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Resync with ip_tables.c as preparation for compat support.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
We're not multiplying the size with the number of CPUs anymore, so the
check is obsolete.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Instead of using a big array of NR_CPUS entries, we can compute the size
needed at runtime, using nr_cpu_ids
This should save some ram (especially on David's machines where NR_CPUS=4096 :
32 KB can be saved per table, and 64KB for dynamically allocated ones (because
of slab/slub alignements) )
In particular, the 'bootstrap' tables are not any more static (in data
section) but on stack as their size is now very small.
This also should reduce the size used on stack in compat functions
(get_info() declares an automatic variable, that could be bigger than kernel
stack size for big NR_CPUS)
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
The IPv4 and IPv6 hook values are identical, yet some code tries to figure
out the "correct" value by looking at the address family. Introduce NF_INET_*
values for both IPv4 and IPv6. The old values are kept in a #ifndef __KERNEL__
section for userspace compatibility.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
With all the users of the double pointers removed, this patch mops up by
finally replacing all occurances of sk_buff ** in the netfilter API by
sk_buff *.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
So I've had a deadlock reported to me. I've found that the sequence of
events goes like this:
1) process A (modprobe) runs to remove ip_tables.ko
2) process B (iptables-restore) runs and calls setsockopt on a netfilter socket,
increasing the ip_tables socket_ops use count
3) process A acquires a file lock on the file ip_tables.ko, calls remove_module
in the kernel, which in turn executes the ip_tables module cleanup routine,
which calls nf_unregister_sockopt
4) nf_unregister_sockopt, seeing that the use count is non-zero, puts the
calling process into uninterruptible sleep, expecting the process using the
socket option code to wake it up when it exits the kernel
4) the user of the socket option code (process B) in do_ipt_get_ctl, calls
ipt_find_table_lock, which in this case calls request_module to load
ip_tables_nat.ko
5) request_module forks a copy of modprobe (process C) to load the module and
blocks until modprobe exits.
6) Process C. forked by request_module process the dependencies of
ip_tables_nat.ko, of which ip_tables.ko is one.
7) Process C attempts to lock the request module and all its dependencies, it
blocks when it attempts to lock ip_tables.ko (which was previously locked in
step 3)
Theres not really any great permanent solution to this that I can see, but I've
developed a two part solution that corrects the problem
Part 1) Modifies the nf_sockopt registration code so that, instead of using a
use counter internal to the nf_sockopt_ops structure, we instead use a pointer
to the registering modules owner to do module reference counting when nf_sockopt
calls a modules set/get routine. This prevents the deadlock by preventing set 4
from happening.
Part 2) Enhances the modprobe utilty so that by default it preforms non-blocking
remove operations (the same way rmmod does), and add an option to explicity
request blocking operation. So if you select blocking operation in modprobe you
can still cause the above deadlock, but only if you explicity try (and since
root can do any old stupid thing it would like.... :) ).
Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Lower ip6tables, arptables and ebtables printk severity similar to
Dan Aloni's patch for iptables.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
The TRACE target can be used to follow IP and IPv6 packets through
the ruleset.
Signed-off-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Signed-off-by: Patrick NcHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Switch the return type of match functions to boolean
Signed-off-by: Jan Engelhardt <jengelh@gmx.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Switch the return type of match functions to boolean
Signed-off-by: Jan Engelhardt <jengelh@gmx.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Switch the "hotdrop" variables to boolean
Signed-off-by: Jan Engelhardt <jengelh@gmx.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Now the skb->nh union has just one member, .raw, i.e. it is just like the
skb->mac union, strange, no? I'm just leaving it like that till the transport
layer is done with, when we'll rename skb->mac.raw to skb->mac_header (or
->mac_header_offset?), ditto for ->{h,nh}.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Use the x_tables functions directly to make it better visible which
parts are shared between ip_tables and ip6_tables.
Signed-off-by: Jan Engelhardt <jengelh@gmx.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
If we come to node we'd already marked as seen and it's not a part of path
(i.e. we don't have a loop right there), we already know that it isn't a
part of any loop, so we don't need to revisit it.
That speeds the things up if some chain is refered to from several places
and kills O(exp(table size)) worst-case behaviour (without sleeping,
at that, so if you manage to self-LART that way, you are SOL for a long
time)...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit 590bdf7fd2 introduced a regression
in match/target hook validation. mark_source_chains builds a bitmask
for each rule representing the hooks it can be reached from, which is
then used by the matches and targets to make sure they are only called
from valid hooks. The patch moved the match/target specific validation
before the mark_source_chains call, at which point the mask is always zero.
This patch returns back to the old order and moves the standard checks
to mark_source_chains. This allows to get rid of a special case for
standard targets as a nice side-effect.
Signed-off-by: Dmitry Mishin <dim@openvz.org>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
nexthdr is NEXTHDR_FRAGMENT, the nexthdr value from the fragment header
is hp->nexthdr.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
There is a number of issues in parsing user-provided table in
translate_table(). Malicious user with CAP_NET_ADMIN may crash system by
passing special-crafted table to the *_tables.
The first issue is that mark_source_chains() function is called before entry
content checks. In case of standard target, mark_source_chains() function
uses t->verdict field in order to determine new position. But the check, that
this field leads no further, than the table end, is in check_entry(), which
is called later, than mark_source_chains().
The second issue, that there is no check that target_offset points inside
entry. If so, *_ITERATE_MATCH macro will follow further, than the entry
ends. As a result, we'll have oops or memory disclosure.
And the third issue, that there is no check that the target is completely
inside entry. Results are the same, as in previous issue.
Signed-off-by: Dmitry Mishin <dim@openvz.org>
Acked-by: Kirill Korotaev <dev@openvz.org>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
As reported by Mark Dowd <Mark_Dowd@McAfee.com>, ip6_tables is susceptible
to a fragmentation attack causing false negatives on extension header matches.
When extension headers occur in the non-first fragment after the fragment
header (possibly with an incorrect nexthdr value in the fragment header)
a rule looking for this extension header will never match.
Drop fragments that are at offset 0 and don't contain the final protocol
header regardless of the ruleset, since this should not happen normally.
Since all extension headers are before the protocol header this makes sure
an extension header is either not present or in the first fragment, where
we can properly parse it.
With help from Yasuyuki KOZAKAI <yasuyuki.kozakai@toshiba.co.jp>.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Jan Engelhardt
Patrick McHardy