2019-06-04 08:11:33 +00:00
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// SPDX-License-Identifier: GPL-2.0-only
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2005-04-16 22:20:36 +00:00
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/*
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* IPv6 packet mangling table, a port of the IPv4 mangle table to IPv6
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*
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* Copyright (C) 2000-2001 by Harald Welte <laforge@gnumonks.org>
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* Copyright (C) 2000-2004 Netfilter Core Team <coreteam@netfilter.org>
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*/
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#include <linux/module.h>
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#include <linux/netfilter_ipv6/ip6_tables.h>
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include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files. percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.
percpu.h -> slab.h dependency is about to be removed. Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability. As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.
http://userweb.kernel.org/~tj/misc/slabh-sweep.py
The script does the followings.
* Scan files for gfp and slab usages and update includes such that
only the necessary includes are there. ie. if only gfp is used,
gfp.h, if slab is used, slab.h.
* When the script inserts a new include, it looks at the include
blocks and try to put the new include such that its order conforms
to its surrounding. It's put in the include block which contains
core kernel includes, in the same order that the rest are ordered -
alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
doesn't seem to be any matching order.
* If the script can't find a place to put a new include (mostly
because the file doesn't have fitting include block), it prints out
an error message indicating which .h file needs to be added to the
file.
The conversion was done in the following steps.
1. The initial automatic conversion of all .c files updated slightly
over 4000 files, deleting around 700 includes and adding ~480 gfp.h
and ~3000 slab.h inclusions. The script emitted errors for ~400
files.
2. Each error was manually checked. Some didn't need the inclusion,
some needed manual addition while adding it to implementation .h or
embedding .c file was more appropriate for others. This step added
inclusions to around 150 files.
3. The script was run again and the output was compared to the edits
from #2 to make sure no file was left behind.
4. Several build tests were done and a couple of problems were fixed.
e.g. lib/decompress_*.c used malloc/free() wrappers around slab
APIs requiring slab.h to be added manually.
5. The script was run on all .h files but without automatically
editing them as sprinkling gfp.h and slab.h inclusions around .h
files could easily lead to inclusion dependency hell. Most gfp.h
inclusion directives were ignored as stuff from gfp.h was usually
wildly available and often used in preprocessor macros. Each
slab.h inclusion directive was examined and added manually as
necessary.
6. percpu.h was updated not to include slab.h.
7. Build test were done on the following configurations and failures
were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
distributed build env didn't work with gcov compiles) and a few
more options had to be turned off depending on archs to make things
build (like ipr on powerpc/64 which failed due to missing writeq).
* x86 and x86_64 UP and SMP allmodconfig and a custom test config.
* powerpc and powerpc64 SMP allmodconfig
* sparc and sparc64 SMP allmodconfig
* ia64 SMP allmodconfig
* s390 SMP allmodconfig
* alpha SMP allmodconfig
* um on x86_64 SMP allmodconfig
8. percpu.h modifications were reverted so that it could be applied as
a separate patch and serve as bisection point.
Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.
Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-24 08:04:11 +00:00
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#include <linux/slab.h>
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2013-01-29 12:48:58 +00:00
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#include <net/ipv6.h>
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2005-04-16 22:20:36 +00:00
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MODULE_LICENSE("GPL");
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MODULE_AUTHOR("Netfilter Core Team <coreteam@netfilter.org>");
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MODULE_DESCRIPTION("ip6tables mangle table");
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2007-11-20 02:53:30 +00:00
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#define MANGLE_VALID_HOOKS ((1 << NF_INET_PRE_ROUTING) | \
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(1 << NF_INET_LOCAL_IN) | \
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(1 << NF_INET_FORWARD) | \
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(1 << NF_INET_LOCAL_OUT) | \
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(1 << NF_INET_POST_ROUTING))
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2005-04-16 22:20:36 +00:00
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2009-08-24 12:56:30 +00:00
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static const struct xt_table packet_mangler = {
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2005-04-16 22:20:36 +00:00
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.name = "mangle",
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.valid_hooks = MANGLE_VALID_HOOKS,
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.me = THIS_MODULE,
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2009-06-13 04:25:44 +00:00
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.af = NFPROTO_IPV6,
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2009-06-17 11:57:48 +00:00
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.priority = NF_IP6_PRI_MANGLE,
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2005-04-16 22:20:36 +00:00
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};
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2008-10-08 09:35:02 +00:00
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static unsigned int
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2021-10-11 15:15:13 +00:00
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ip6t_mangle_out(void *priv, struct sk_buff *skb, const struct nf_hook_state *state)
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2005-04-16 22:20:36 +00:00
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{
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struct in6_addr saddr, daddr;
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2023-10-11 07:59:34 +00:00
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unsigned int ret, verdict;
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u32 flowlabel, mark;
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u8 hop_limit;
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2013-04-05 06:41:11 +00:00
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int err;
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2005-04-16 22:20:36 +00:00
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2006-11-09 23:19:14 +00:00
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/* save source/dest address, mark, hoplimit, flowlabel, priority, */
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2007-10-15 07:53:15 +00:00
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memcpy(&saddr, &ipv6_hdr(skb)->saddr, sizeof(saddr));
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memcpy(&daddr, &ipv6_hdr(skb)->daddr, sizeof(daddr));
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mark = skb->mark;
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hop_limit = ipv6_hdr(skb)->hop_limit;
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2005-04-16 22:20:36 +00:00
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/* flowlabel and prio (includes version, which shouldn't change either */
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2007-10-15 07:53:15 +00:00
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flowlabel = *((u_int32_t *)ipv6_hdr(skb));
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2005-04-16 22:20:36 +00:00
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2021-10-11 15:15:13 +00:00
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ret = ip6t_do_table(priv, skb, state);
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2023-10-11 07:59:34 +00:00
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verdict = ret & NF_VERDICT_MASK;
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2005-04-16 22:20:36 +00:00
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2023-10-11 07:59:34 +00:00
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if (verdict != NF_DROP && verdict != NF_STOLEN &&
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2013-01-29 12:48:58 +00:00
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(!ipv6_addr_equal(&ipv6_hdr(skb)->saddr, &saddr) ||
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!ipv6_addr_equal(&ipv6_hdr(skb)->daddr, &daddr) ||
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2009-11-23 22:17:06 +00:00
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skb->mark != mark ||
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2011-04-18 00:06:15 +00:00
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ipv6_hdr(skb)->hop_limit != hop_limit ||
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2013-04-05 06:41:11 +00:00
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flowlabel != *((u_int32_t *)ipv6_hdr(skb)))) {
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netfilter: use actual socket sk rather than skb sk when routing harder
If netfilter changes the packet mark when mangling, the packet is
rerouted using the route_me_harder set of functions. Prior to this
commit, there's one big difference between route_me_harder and the
ordinary initial routing functions, described in the comment above
__ip_queue_xmit():
/* Note: skb->sk can be different from sk, in case of tunnels */
int __ip_queue_xmit(struct sock *sk, struct sk_buff *skb, struct flowi *fl,
That function goes on to correctly make use of sk->sk_bound_dev_if,
rather than skb->sk->sk_bound_dev_if. And indeed the comment is true: a
tunnel will receive a packet in ndo_start_xmit with an initial skb->sk.
It will make some transformations to that packet, and then it will send
the encapsulated packet out of a *new* socket. That new socket will
basically always have a different sk_bound_dev_if (otherwise there'd be
a routing loop). So for the purposes of routing the encapsulated packet,
the routing information as it pertains to the socket should come from
that socket's sk, rather than the packet's original skb->sk. For that
reason __ip_queue_xmit() and related functions all do the right thing.
One might argue that all tunnels should just call skb_orphan(skb) before
transmitting the encapsulated packet into the new socket. But tunnels do
*not* do this -- and this is wisely avoided in skb_scrub_packet() too --
because features like TSQ rely on skb->destructor() being called when
that buffer space is truely available again. Calling skb_orphan(skb) too
early would result in buffers filling up unnecessarily and accounting
info being all wrong. Instead, additional routing must take into account
the new sk, just as __ip_queue_xmit() notes.
So, this commit addresses the problem by fishing the correct sk out of
state->sk -- it's already set properly in the call to nf_hook() in
__ip_local_out(), which receives the sk as part of its normal
functionality. So we make sure to plumb state->sk through the various
route_me_harder functions, and then make correct use of it following the
example of __ip_queue_xmit().
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Reviewed-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2020-10-29 02:56:06 +00:00
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err = ip6_route_me_harder(state->net, state->sk, skb);
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2013-04-05 06:41:11 +00:00
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if (err < 0)
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ret = NF_DROP_ERR(err);
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}
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2005-04-16 22:20:36 +00:00
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return ret;
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}
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2009-06-13 04:46:36 +00:00
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/* The work comes in here from netfilter.c. */
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static unsigned int
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2015-09-18 19:33:06 +00:00
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ip6table_mangle_hook(void *priv, struct sk_buff *skb,
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2015-04-04 00:32:56 +00:00
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const struct nf_hook_state *state)
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2009-06-13 04:46:36 +00:00
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{
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2015-09-18 19:32:55 +00:00
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if (state->hook == NF_INET_LOCAL_OUT)
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2021-10-11 15:15:13 +00:00
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return ip6t_mangle_out(priv, skb, state);
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return ip6t_do_table(priv, skb, state);
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2009-06-13 04:46:36 +00:00
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}
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2009-06-17 11:57:48 +00:00
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static struct nf_hook_ops *mangle_ops __read_mostly;
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2021-08-03 14:47:19 +00:00
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static int ip6table_mangle_table_init(struct net *net)
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2008-01-31 12:04:13 +00:00
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{
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2009-06-17 20:14:54 +00:00
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struct ip6t_replace *repl;
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2016-02-25 09:08:35 +00:00
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int ret;
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2009-06-17 20:14:54 +00:00
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repl = ip6t_alloc_initial_table(&packet_mangler);
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if (repl == NULL)
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return -ENOMEM;
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2021-04-21 07:51:09 +00:00
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ret = ip6t_register_table(net, &packet_mangler, repl, mangle_ops);
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2009-06-17 20:14:54 +00:00
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kfree(repl);
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2016-02-25 09:08:35 +00:00
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return ret;
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2008-01-31 12:04:13 +00:00
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}
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2020-06-22 17:10:14 +00:00
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static void __net_exit ip6table_mangle_net_pre_exit(struct net *net)
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{
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2021-04-21 07:51:09 +00:00
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ip6t_unregister_table_pre_exit(net, "mangle");
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2020-06-22 17:10:14 +00:00
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}
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2008-01-31 12:04:13 +00:00
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static void __net_exit ip6table_mangle_net_exit(struct net *net)
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{
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2021-04-21 07:51:03 +00:00
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ip6t_unregister_table_exit(net, "mangle");
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2008-01-31 12:04:13 +00:00
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}
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static struct pernet_operations ip6table_mangle_net_ops = {
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2020-06-22 17:10:14 +00:00
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.pre_exit = ip6table_mangle_net_pre_exit,
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2008-01-31 12:04:13 +00:00
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.exit = ip6table_mangle_net_exit,
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};
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2006-03-29 00:37:06 +00:00
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static int __init ip6table_mangle_init(void)
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2005-04-16 22:20:36 +00:00
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{
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2021-08-03 14:47:19 +00:00
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int ret = xt_register_template(&packet_mangler,
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ip6table_mangle_table_init);
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if (ret < 0)
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return ret;
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2005-04-16 22:20:36 +00:00
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netfilter: xtables: don't hook tables by default
delay hook registration until the table is being requested inside a
namespace.
Historically, a particular table (iptables mangle, ip6tables filter, etc)
was registered on module load.
When netns support was added to iptables only the ip/ip6tables ruleset was
made namespace aware, not the actual hook points.
This means f.e. that when ipt_filter table/module is loaded on a system,
then each namespace on that system has an (empty) iptables filter ruleset.
In other words, if a namespace sends a packet, such skb is 'caught' by
netfilter machinery and fed to hooking points for that table (i.e. INPUT,
FORWARD, etc).
Thanks to Eric Biederman, hooks are no longer global, but per namespace.
This means that we can avoid allocation of empty ruleset in a namespace and
defer hook registration until we need the functionality.
We register a tables hook entry points ONLY in the initial namespace.
When an iptables get/setockopt is issued inside a given namespace, we check
if the table is found in the per-namespace list.
If not, we attempt to find it in the initial namespace, and, if found,
create an empty default table in the requesting namespace and register the
needed hooks.
Hook points are destroyed only once namespace is deleted, there is no
'usage count' (it makes no sense since there is no 'remove table' operation
in xtables api).
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-02-25 09:08:36 +00:00
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mangle_ops = xt_hook_ops_alloc(&packet_mangler, ip6table_mangle_hook);
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2021-08-03 14:47:19 +00:00
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if (IS_ERR(mangle_ops)) {
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xt_unregister_template(&packet_mangler);
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netfilter: xtables: don't hook tables by default
delay hook registration until the table is being requested inside a
namespace.
Historically, a particular table (iptables mangle, ip6tables filter, etc)
was registered on module load.
When netns support was added to iptables only the ip/ip6tables ruleset was
made namespace aware, not the actual hook points.
This means f.e. that when ipt_filter table/module is loaded on a system,
then each namespace on that system has an (empty) iptables filter ruleset.
In other words, if a namespace sends a packet, such skb is 'caught' by
netfilter machinery and fed to hooking points for that table (i.e. INPUT,
FORWARD, etc).
Thanks to Eric Biederman, hooks are no longer global, but per namespace.
This means that we can avoid allocation of empty ruleset in a namespace and
defer hook registration until we need the functionality.
We register a tables hook entry points ONLY in the initial namespace.
When an iptables get/setockopt is issued inside a given namespace, we check
if the table is found in the per-namespace list.
If not, we attempt to find it in the initial namespace, and, if found,
create an empty default table in the requesting namespace and register the
needed hooks.
Hook points are destroyed only once namespace is deleted, there is no
'usage count' (it makes no sense since there is no 'remove table' operation
in xtables api).
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-02-25 09:08:36 +00:00
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return PTR_ERR(mangle_ops);
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2021-08-03 14:47:19 +00:00
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}
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netfilter: xtables: don't hook tables by default
delay hook registration until the table is being requested inside a
namespace.
Historically, a particular table (iptables mangle, ip6tables filter, etc)
was registered on module load.
When netns support was added to iptables only the ip/ip6tables ruleset was
made namespace aware, not the actual hook points.
This means f.e. that when ipt_filter table/module is loaded on a system,
then each namespace on that system has an (empty) iptables filter ruleset.
In other words, if a namespace sends a packet, such skb is 'caught' by
netfilter machinery and fed to hooking points for that table (i.e. INPUT,
FORWARD, etc).
Thanks to Eric Biederman, hooks are no longer global, but per namespace.
This means that we can avoid allocation of empty ruleset in a namespace and
defer hook registration until we need the functionality.
We register a tables hook entry points ONLY in the initial namespace.
When an iptables get/setockopt is issued inside a given namespace, we check
if the table is found in the per-namespace list.
If not, we attempt to find it in the initial namespace, and, if found,
create an empty default table in the requesting namespace and register the
needed hooks.
Hook points are destroyed only once namespace is deleted, there is no
'usage count' (it makes no sense since there is no 'remove table' operation
in xtables api).
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-02-25 09:08:36 +00:00
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2008-01-31 12:04:13 +00:00
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ret = register_pernet_subsys(&ip6table_mangle_net_ops);
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netfilter: xtables: don't hook tables by default
delay hook registration until the table is being requested inside a
namespace.
Historically, a particular table (iptables mangle, ip6tables filter, etc)
was registered on module load.
When netns support was added to iptables only the ip/ip6tables ruleset was
made namespace aware, not the actual hook points.
This means f.e. that when ipt_filter table/module is loaded on a system,
then each namespace on that system has an (empty) iptables filter ruleset.
In other words, if a namespace sends a packet, such skb is 'caught' by
netfilter machinery and fed to hooking points for that table (i.e. INPUT,
FORWARD, etc).
Thanks to Eric Biederman, hooks are no longer global, but per namespace.
This means that we can avoid allocation of empty ruleset in a namespace and
defer hook registration until we need the functionality.
We register a tables hook entry points ONLY in the initial namespace.
When an iptables get/setockopt is issued inside a given namespace, we check
if the table is found in the per-namespace list.
If not, we attempt to find it in the initial namespace, and, if found,
create an empty default table in the requesting namespace and register the
needed hooks.
Hook points are destroyed only once namespace is deleted, there is no
'usage count' (it makes no sense since there is no 'remove table' operation
in xtables api).
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-02-25 09:08:36 +00:00
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if (ret < 0) {
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2021-08-03 14:47:19 +00:00
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xt_unregister_template(&packet_mangler);
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netfilter: xtables: don't hook tables by default
delay hook registration until the table is being requested inside a
namespace.
Historically, a particular table (iptables mangle, ip6tables filter, etc)
was registered on module load.
When netns support was added to iptables only the ip/ip6tables ruleset was
made namespace aware, not the actual hook points.
This means f.e. that when ipt_filter table/module is loaded on a system,
then each namespace on that system has an (empty) iptables filter ruleset.
In other words, if a namespace sends a packet, such skb is 'caught' by
netfilter machinery and fed to hooking points for that table (i.e. INPUT,
FORWARD, etc).
Thanks to Eric Biederman, hooks are no longer global, but per namespace.
This means that we can avoid allocation of empty ruleset in a namespace and
defer hook registration until we need the functionality.
We register a tables hook entry points ONLY in the initial namespace.
When an iptables get/setockopt is issued inside a given namespace, we check
if the table is found in the per-namespace list.
If not, we attempt to find it in the initial namespace, and, if found,
create an empty default table in the requesting namespace and register the
needed hooks.
Hook points are destroyed only once namespace is deleted, there is no
'usage count' (it makes no sense since there is no 'remove table' operation
in xtables api).
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-02-25 09:08:36 +00:00
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kfree(mangle_ops);
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2008-01-31 12:04:13 +00:00
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return ret;
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2009-06-17 11:57:48 +00:00
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}
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2005-04-16 22:20:36 +00:00
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return ret;
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}
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2006-03-29 00:37:06 +00:00
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static void __exit ip6table_mangle_fini(void)
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2005-04-16 22:20:36 +00:00
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{
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2008-01-31 12:04:13 +00:00
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unregister_pernet_subsys(&ip6table_mangle_net_ops);
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2021-08-03 14:47:19 +00:00
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xt_unregister_template(&packet_mangler);
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netfilter: xtables: don't hook tables by default
delay hook registration until the table is being requested inside a
namespace.
Historically, a particular table (iptables mangle, ip6tables filter, etc)
was registered on module load.
When netns support was added to iptables only the ip/ip6tables ruleset was
made namespace aware, not the actual hook points.
This means f.e. that when ipt_filter table/module is loaded on a system,
then each namespace on that system has an (empty) iptables filter ruleset.
In other words, if a namespace sends a packet, such skb is 'caught' by
netfilter machinery and fed to hooking points for that table (i.e. INPUT,
FORWARD, etc).
Thanks to Eric Biederman, hooks are no longer global, but per namespace.
This means that we can avoid allocation of empty ruleset in a namespace and
defer hook registration until we need the functionality.
We register a tables hook entry points ONLY in the initial namespace.
When an iptables get/setockopt is issued inside a given namespace, we check
if the table is found in the per-namespace list.
If not, we attempt to find it in the initial namespace, and, if found,
create an empty default table in the requesting namespace and register the
needed hooks.
Hook points are destroyed only once namespace is deleted, there is no
'usage count' (it makes no sense since there is no 'remove table' operation
in xtables api).
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-02-25 09:08:36 +00:00
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kfree(mangle_ops);
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2005-04-16 22:20:36 +00:00
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}
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2006-03-29 00:37:06 +00:00
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module_init(ip6table_mangle_init);
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module_exit(ip6table_mangle_fini);
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