2006-12-02 23:09:06 -07:00
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/* IRC extension for IP connection tracking, Version 1.21
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* (C) 2000-2002 by Harald Welte <laforge@gnumonks.org>
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* based on RR's ip_conntrack_ftp.c
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2013-04-06 07:24:29 -06:00
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* (C) 2006-2012 Patrick McHardy <kaber@trash.net>
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2006-12-02 23:09:06 -07:00
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version
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* 2 of the License, or (at your option) any later version.
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*/
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#include <linux/module.h>
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#include <linux/moduleparam.h>
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#include <linux/skbuff.h>
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#include <linux/in.h>
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2007-07-07 23:39:38 -06:00
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#include <linux/ip.h>
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2006-12-02 23:09:06 -07:00
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#include <linux/tcp.h>
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#include <linux/netfilter.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 02:04:11 -06:00
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#include <linux/slab.h>
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2006-12-02 23:09:06 -07:00
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#include <net/netfilter/nf_conntrack.h>
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#include <net/netfilter/nf_conntrack_expect.h>
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#include <net/netfilter/nf_conntrack_helper.h>
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#include <linux/netfilter/nf_conntrack_irc.h>
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#define MAX_PORTS 8
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static unsigned short ports[MAX_PORTS];
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2008-01-31 05:08:10 -07:00
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static unsigned int ports_c;
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2006-12-02 23:09:06 -07:00
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static unsigned int max_dcc_channels = 8;
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static unsigned int dcc_timeout __read_mostly = 300;
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/* This is slow, but it's simple. --RR */
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static char *irc_buffer;
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static DEFINE_SPINLOCK(irc_buffer_lock);
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2007-10-15 01:53:15 -06:00
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unsigned int (*nf_nat_irc_hook)(struct sk_buff *skb,
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2006-12-02 23:09:06 -07:00
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enum ip_conntrack_info ctinfo,
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2012-08-26 11:14:04 -06:00
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unsigned int protoff,
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2006-12-02 23:09:06 -07:00
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unsigned int matchoff,
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unsigned int matchlen,
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struct nf_conntrack_expect *exp) __read_mostly;
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EXPORT_SYMBOL_GPL(nf_nat_irc_hook);
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MODULE_AUTHOR("Harald Welte <laforge@netfilter.org>");
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MODULE_DESCRIPTION("IRC (DCC) connection tracking helper");
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MODULE_LICENSE("GPL");
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MODULE_ALIAS("ip_conntrack_irc");
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2008-11-17 08:01:42 -07:00
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MODULE_ALIAS_NFCT_HELPER("irc");
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2006-12-02 23:09:06 -07:00
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module_param_array(ports, ushort, &ports_c, 0400);
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MODULE_PARM_DESC(ports, "port numbers of IRC servers");
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module_param(max_dcc_channels, uint, 0400);
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MODULE_PARM_DESC(max_dcc_channels, "max number of expected DCC channels per "
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"IRC session");
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module_param(dcc_timeout, uint, 0400);
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MODULE_PARM_DESC(dcc_timeout, "timeout on for unestablished DCC channels");
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2008-04-14 03:15:42 -06:00
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static const char *const dccprotos[] = {
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2006-12-02 23:09:06 -07:00
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"SEND ", "CHAT ", "MOVE ", "TSEND ", "SCHAT "
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};
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#define MINMATCHLEN 5
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/* tries to get the ip_addr and port out of a dcc command
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* return value: -1 on failure, 0 on success
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* data pointer to first byte of DCC command data
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* data_end pointer to last byte of dcc command data
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* ip returns parsed ip of dcc command
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* port returns parsed port of dcc command
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* ad_beg_p returns pointer to first byte of addr data
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* ad_end_p returns pointer to last byte of addr data
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*/
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2009-03-28 09:38:30 -06:00
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static int parse_dcc(char *data, const char *data_end, __be32 *ip,
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2006-12-02 23:09:06 -07:00
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u_int16_t *port, char **ad_beg_p, char **ad_end_p)
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{
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2008-09-07 19:21:24 -06:00
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char *tmp;
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2006-12-02 23:09:06 -07:00
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/* at least 12: "AAAAAAAA P\1\n" */
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while (*data++ != ' ')
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if (data > data_end - 12)
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return -1;
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2008-09-07 19:21:24 -06:00
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/* Make sure we have a newline character within the packet boundaries
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* because simple_strtoul parses until the first invalid character. */
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for (tmp = data; tmp <= data_end; tmp++)
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if (*tmp == '\n')
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break;
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if (tmp > data_end || *tmp != '\n')
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return -1;
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2006-12-02 23:09:06 -07:00
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*ad_beg_p = data;
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2009-03-28 09:38:30 -06:00
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*ip = cpu_to_be32(simple_strtoul(data, &data, 10));
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2006-12-02 23:09:06 -07:00
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/* skip blanks between ip and port */
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while (*data == ' ') {
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if (data >= data_end)
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return -1;
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data++;
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}
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*port = simple_strtoul(data, &data, 10);
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*ad_end_p = data;
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return 0;
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}
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2007-10-15 01:53:15 -06:00
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static int help(struct sk_buff *skb, unsigned int protoff,
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2006-12-02 23:09:06 -07:00
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struct nf_conn *ct, enum ip_conntrack_info ctinfo)
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{
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unsigned int dataoff;
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2008-04-14 03:15:42 -06:00
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const struct iphdr *iph;
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const struct tcphdr *th;
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struct tcphdr _tcph;
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const char *data_limit;
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char *data, *ib_ptr;
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2006-12-02 23:09:06 -07:00
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int dir = CTINFO2DIR(ctinfo);
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struct nf_conntrack_expect *exp;
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struct nf_conntrack_tuple *tuple;
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2009-03-28 09:38:30 -06:00
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__be32 dcc_ip;
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2006-12-02 23:09:06 -07:00
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u_int16_t dcc_port;
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__be16 port;
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int i, ret = NF_ACCEPT;
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char *addr_beg_p, *addr_end_p;
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typeof(nf_nat_irc_hook) nf_nat_irc;
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/* If packet is coming from IRC server */
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if (dir == IP_CT_DIR_REPLY)
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return NF_ACCEPT;
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/* Until there's been traffic both ways, don't look in packets. */
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2011-05-19 07:44:27 -06:00
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if (ctinfo != IP_CT_ESTABLISHED && ctinfo != IP_CT_ESTABLISHED_REPLY)
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2006-12-02 23:09:06 -07:00
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return NF_ACCEPT;
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/* Not a full tcp header? */
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2007-10-15 01:53:15 -06:00
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th = skb_header_pointer(skb, protoff, sizeof(_tcph), &_tcph);
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2006-12-02 23:09:06 -07:00
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if (th == NULL)
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return NF_ACCEPT;
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/* No data? */
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dataoff = protoff + th->doff*4;
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2007-10-15 01:53:15 -06:00
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if (dataoff >= skb->len)
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2006-12-02 23:09:06 -07:00
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return NF_ACCEPT;
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spin_lock_bh(&irc_buffer_lock);
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2007-10-15 01:53:15 -06:00
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ib_ptr = skb_header_pointer(skb, dataoff, skb->len - dataoff,
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2006-12-02 23:09:06 -07:00
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irc_buffer);
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BUG_ON(ib_ptr == NULL);
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data = ib_ptr;
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2007-10-15 01:53:15 -06:00
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data_limit = ib_ptr + skb->len - dataoff;
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2006-12-02 23:09:06 -07:00
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/* strlen("\1DCC SENT t AAAAAAAA P\1\n")=24
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* 5+MINMATCHLEN+strlen("t AAAAAAAA P\1\n")=14 */
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while (data < data_limit - (19 + MINMATCHLEN)) {
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if (memcmp(data, "\1DCC ", 5)) {
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data++;
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continue;
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}
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data += 5;
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/* we have at least (19+MINMATCHLEN)-5 bytes valid data left */
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|
2007-10-15 01:53:15 -06:00
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iph = ip_hdr(skb);
|
2008-10-31 01:54:29 -06:00
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pr_debug("DCC found in master %pI4:%u %pI4:%u\n",
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&iph->saddr, ntohs(th->source),
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&iph->daddr, ntohs(th->dest));
|
2006-12-02 23:09:06 -07:00
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for (i = 0; i < ARRAY_SIZE(dccprotos); i++) {
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if (memcmp(data, dccprotos[i], strlen(dccprotos[i]))) {
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/* no match */
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continue;
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}
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data += strlen(dccprotos[i]);
|
2007-07-07 23:39:38 -06:00
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pr_debug("DCC %s detected\n", dccprotos[i]);
|
2006-12-02 23:09:06 -07:00
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/* we have at least
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* (19+MINMATCHLEN)-5-dccprotos[i].matchlen bytes valid
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* data left (== 14/13 bytes) */
|
2008-04-14 03:15:42 -06:00
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if (parse_dcc(data, data_limit, &dcc_ip,
|
2006-12-02 23:09:06 -07:00
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&dcc_port, &addr_beg_p, &addr_end_p)) {
|
2007-07-07 23:39:38 -06:00
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pr_debug("unable to parse dcc command\n");
|
2006-12-02 23:09:06 -07:00
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continue;
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}
|
2009-03-28 09:38:30 -06:00
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pr_debug("DCC bound ip/port: %pI4:%u\n",
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&dcc_ip, dcc_port);
|
2006-12-02 23:09:06 -07:00
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/* dcc_ip can be the internal OR external (NAT'ed) IP */
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tuple = &ct->tuplehash[dir].tuple;
|
2009-03-28 09:38:30 -06:00
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if (tuple->src.u3.ip != dcc_ip &&
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tuple->dst.u3.ip != dcc_ip) {
|
2012-05-13 15:56:26 -06:00
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|
net_warn_ratelimited("Forged DCC command from %pI4: %pI4:%u\n",
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&tuple->src.u3.ip,
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&dcc_ip, dcc_port);
|
2006-12-02 23:09:06 -07:00
|
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|
continue;
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}
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|
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|
|
2007-07-07 23:30:49 -06:00
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|
exp = nf_ct_expect_alloc(ct);
|
2006-12-02 23:09:06 -07:00
|
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|
if (exp == NULL) {
|
2013-02-10 10:56:56 -07:00
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|
|
nf_ct_helper_log(skb, ct,
|
|
|
|
"cannot alloc expectation");
|
2006-12-02 23:09:06 -07:00
|
|
|
ret = NF_DROP;
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|
|
goto out;
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|
|
|
}
|
|
|
|
tuple = &ct->tuplehash[!dir].tuple;
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|
|
|
port = htons(dcc_port);
|
2008-03-25 21:09:15 -06:00
|
|
|
nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT,
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|
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tuple->src.l3num,
|
2007-07-07 23:30:49 -06:00
|
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NULL, &tuple->dst.u3,
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|
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IPPROTO_TCP, NULL, &port);
|
2006-12-02 23:09:06 -07:00
|
|
|
|
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|
|
nf_nat_irc = rcu_dereference(nf_nat_irc_hook);
|
2012-08-26 11:14:27 -06:00
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|
|
if (nf_nat_irc && ct->status & IPS_NAT_MASK)
|
2012-08-26 11:14:04 -06:00
|
|
|
ret = nf_nat_irc(skb, ctinfo, protoff,
|
2006-12-02 23:09:06 -07:00
|
|
|
addr_beg_p - ib_ptr,
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|
|
addr_end_p - addr_beg_p,
|
|
|
|
exp);
|
2013-02-10 10:56:56 -07:00
|
|
|
else if (nf_ct_expect_related(exp) != 0) {
|
|
|
|
nf_ct_helper_log(skb, ct,
|
|
|
|
"cannot add expectation");
|
2006-12-02 23:09:06 -07:00
|
|
|
ret = NF_DROP;
|
2013-02-10 10:56:56 -07:00
|
|
|
}
|
2007-07-07 23:30:49 -06:00
|
|
|
nf_ct_expect_put(exp);
|
2006-12-02 23:09:06 -07:00
|
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|
goto out;
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|
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}
|
|
|
|
}
|
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|
out:
|
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|
|
spin_unlock_bh(&irc_buffer_lock);
|
|
|
|
return ret;
|
|
|
|
}
|
|
|
|
|
|
|
|
static struct nf_conntrack_helper irc[MAX_PORTS] __read_mostly;
|
2008-03-25 21:09:15 -06:00
|
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|
static struct nf_conntrack_expect_policy irc_exp_policy;
|
2006-12-02 23:09:06 -07:00
|
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|
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|
static void nf_conntrack_irc_fini(void);
|
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|
|
|
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|
|
static int __init nf_conntrack_irc_init(void)
|
|
|
|
{
|
|
|
|
int i, ret;
|
|
|
|
|
|
|
|
if (max_dcc_channels < 1) {
|
2010-05-13 07:02:08 -06:00
|
|
|
printk(KERN_ERR "nf_ct_irc: max_dcc_channels must not be zero\n");
|
2006-12-02 23:09:06 -07:00
|
|
|
return -EINVAL;
|
|
|
|
}
|
|
|
|
|
2008-03-25 21:09:15 -06:00
|
|
|
irc_exp_policy.max_expected = max_dcc_channels;
|
|
|
|
irc_exp_policy.timeout = dcc_timeout;
|
|
|
|
|
2006-12-02 23:09:06 -07:00
|
|
|
irc_buffer = kmalloc(65536, GFP_KERNEL);
|
|
|
|
if (!irc_buffer)
|
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|
|
return -ENOMEM;
|
|
|
|
|
|
|
|
/* If no port given, default to standard irc port */
|
|
|
|
if (ports_c == 0)
|
|
|
|
ports[ports_c++] = IRC_PORT;
|
|
|
|
|
|
|
|
for (i = 0; i < ports_c; i++) {
|
|
|
|
irc[i].tuple.src.l3num = AF_INET;
|
|
|
|
irc[i].tuple.src.u.tcp.port = htons(ports[i]);
|
|
|
|
irc[i].tuple.dst.protonum = IPPROTO_TCP;
|
2008-03-25 21:09:15 -06:00
|
|
|
irc[i].expect_policy = &irc_exp_policy;
|
2006-12-02 23:09:06 -07:00
|
|
|
irc[i].me = THIS_MODULE;
|
|
|
|
irc[i].help = help;
|
|
|
|
|
|
|
|
if (ports[i] == IRC_PORT)
|
2012-01-15 08:34:08 -07:00
|
|
|
sprintf(irc[i].name, "irc");
|
2006-12-02 23:09:06 -07:00
|
|
|
else
|
2012-01-15 08:34:08 -07:00
|
|
|
sprintf(irc[i].name, "irc-%u", i);
|
2006-12-02 23:09:06 -07:00
|
|
|
|
|
|
|
ret = nf_conntrack_helper_register(&irc[i]);
|
|
|
|
if (ret) {
|
2010-05-13 07:02:08 -06:00
|
|
|
printk(KERN_ERR "nf_ct_irc: failed to register helper "
|
2006-12-02 23:09:06 -07:00
|
|
|
"for pf: %u port: %u\n",
|
|
|
|
irc[i].tuple.src.l3num, ports[i]);
|
|
|
|
nf_conntrack_irc_fini();
|
|
|
|
return ret;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
/* This function is intentionally _NOT_ defined as __exit, because
|
|
|
|
* it is needed by the init function */
|
|
|
|
static void nf_conntrack_irc_fini(void)
|
|
|
|
{
|
|
|
|
int i;
|
|
|
|
|
|
|
|
for (i = 0; i < ports_c; i++)
|
|
|
|
nf_conntrack_helper_unregister(&irc[i]);
|
|
|
|
kfree(irc_buffer);
|
|
|
|
}
|
|
|
|
|
|
|
|
module_init(nf_conntrack_irc_init);
|
|
|
|
module_exit(nf_conntrack_irc_fini);
|