Contributors: 11
| Author |
Tokens |
Token Proportion |
Commits |
Commit Proportion |
| Patrick McHardy |
257 |
63.61% |
4 |
25.00% |
| Daniel Borkmann |
67 |
16.58% |
1 |
6.25% |
| Flavio Leitner |
28 |
6.93% |
2 |
12.50% |
| Pablo Neira Ayuso |
23 |
5.69% |
2 |
12.50% |
| Arushi Singhal |
11 |
2.72% |
1 |
6.25% |
| Gao Feng |
7 |
1.73% |
1 |
6.25% |
| Florian Westphal |
4 |
0.99% |
1 |
6.25% |
| Herbert Xu |
2 |
0.50% |
1 |
6.25% |
| Stephen Hemminger |
2 |
0.50% |
1 |
6.25% |
| Thomas Gleixner |
2 |
0.50% |
1 |
6.25% |
| Kees Cook |
1 |
0.25% |
1 |
6.25% |
| Total |
404 |
|
16 |
|
// SPDX-License-Identifier: GPL-2.0-or-later
/* IRC extension for TCP NAT alteration.
*
* (C) 2000-2001 by Harald Welte <laforge@gnumonks.org>
* (C) 2004 Rusty Russell <rusty@rustcorp.com.au> IBM Corporation
* based on a copy of RR's ip_nat_ftp.c
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/tcp.h>
#include <linux/kernel.h>
#include <net/netfilter/nf_nat.h>
#include <net/netfilter/nf_nat_helper.h>
#include <net/netfilter/nf_conntrack_helper.h>
#include <net/netfilter/nf_conntrack_expect.h>
#include <linux/netfilter/nf_conntrack_irc.h>
#define NAT_HELPER_NAME "irc"
MODULE_AUTHOR("Harald Welte <laforge@gnumonks.org>");
MODULE_DESCRIPTION("IRC (DCC) NAT helper");
MODULE_LICENSE("GPL");
MODULE_ALIAS_NF_NAT_HELPER(NAT_HELPER_NAME);
static struct nf_conntrack_nat_helper nat_helper_irc =
NF_CT_NAT_HELPER_INIT(NAT_HELPER_NAME);
static unsigned int help(struct sk_buff *skb,
enum ip_conntrack_info ctinfo,
unsigned int protoff,
unsigned int matchoff,
unsigned int matchlen,
struct nf_conntrack_expect *exp)
{
char buffer[sizeof("4294967296 65635")];
struct nf_conn *ct = exp->master;
union nf_inet_addr newaddr;
u_int16_t port;
/* Reply comes from server. */
newaddr = ct->tuplehash[IP_CT_DIR_REPLY].tuple.dst.u3;
exp->saved_proto.tcp.port = exp->tuple.dst.u.tcp.port;
exp->dir = IP_CT_DIR_REPLY;
exp->expectfn = nf_nat_follow_master;
port = nf_nat_exp_find_port(exp,
ntohs(exp->saved_proto.tcp.port));
if (port == 0) {
nf_ct_helper_log(skb, ct, "all ports in use");
return NF_DROP;
}
/* strlen("\1DCC CHAT chat AAAAAAAA P\1\n")=27
* strlen("\1DCC SCHAT chat AAAAAAAA P\1\n")=28
* strlen("\1DCC SEND F AAAAAAAA P S\1\n")=26
* strlen("\1DCC MOVE F AAAAAAAA P S\1\n")=26
* strlen("\1DCC TSEND F AAAAAAAA P S\1\n")=27
*
* AAAAAAAAA: bound addr (1.0.0.0==16777216, min 8 digits,
* 255.255.255.255==4294967296, 10 digits)
* P: bound port (min 1 d, max 5d (65635))
* F: filename (min 1 d )
* S: size (min 1 d )
* 0x01, \n: terminators
*/
/* AAA = "us", ie. where server normally talks to. */
snprintf(buffer, sizeof(buffer), "%u %u", ntohl(newaddr.ip), port);
pr_debug("inserting '%s' == %pI4, port %u\n",
buffer, &newaddr.ip, port);
if (!nf_nat_mangle_tcp_packet(skb, ct, ctinfo, protoff, matchoff,
matchlen, buffer, strlen(buffer))) {
nf_ct_helper_log(skb, ct, "cannot mangle packet");
nf_ct_unexpect_related(exp);
return NF_DROP;
}
return NF_ACCEPT;
}
static void __exit nf_nat_irc_fini(void)
{
nf_nat_helper_unregister(&nat_helper_irc);
RCU_INIT_POINTER(nf_nat_irc_hook, NULL);
synchronize_rcu();
}
static int __init nf_nat_irc_init(void)
{
BUG_ON(nf_nat_irc_hook != NULL);
nf_nat_helper_register(&nat_helper_irc);
RCU_INIT_POINTER(nf_nat_irc_hook, help);
return 0;
}
/* Prior to 2.6.11, we had a ports param. No longer, but don't break users. */
static int warn_set(const char *val, const struct kernel_param *kp)
{
pr_info("kernel >= 2.6.10 only uses 'ports' for conntrack modules\n");
return 0;
}
module_param_call(ports, warn_set, NULL, NULL, 0);
module_init(nf_nat_irc_init);
module_exit(nf_nat_irc_fini);