Contributors: 17
| Author |
Tokens |
Token Proportion |
Commits |
Commit Proportion |
| Jozsef Kadlecsik |
266 |
42.49% |
1 |
3.12% |
| Joe Perches |
151 |
24.12% |
1 |
3.12% |
| Patrick McHardy |
61 |
9.74% |
6 |
18.75% |
| Yasuyuki Kozakai |
32 |
5.11% |
1 |
3.12% |
| Flavio Leitner |
28 |
4.47% |
2 |
6.25% |
| Pablo Neira Ayuso |
22 |
3.51% |
2 |
6.25% |
| Linus Torvalds (pre-git) |
20 |
3.19% |
6 |
18.75% |
| Harald Welte |
13 |
2.08% |
4 |
12.50% |
| Arushi Singhal |
11 |
1.76% |
1 |
3.12% |
| Florian Westphal |
7 |
1.12% |
1 |
3.12% |
| Martin Josefsson |
3 |
0.48% |
1 |
3.12% |
| Linus Torvalds |
3 |
0.48% |
1 |
3.12% |
| Stephen Hemminger |
2 |
0.32% |
1 |
3.12% |
| Herbert Xu |
2 |
0.32% |
1 |
3.12% |
| Thomas Gleixner |
2 |
0.32% |
1 |
3.12% |
| Rusty Russell |
2 |
0.32% |
1 |
3.12% |
| Kees Cook |
1 |
0.16% |
1 |
3.12% |
| Total |
626 |
|
32 |
|
// SPDX-License-Identifier: GPL-2.0-only
/* FTP extension for TCP NAT alteration. */
/* (C) 1999-2001 Paul `Rusty' Russell
* (C) 2002-2006 Netfilter Core Team <coreteam@netfilter.org>
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/inet.h>
#include <linux/tcp.h>
#include <linux/netfilter_ipv4.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_ftp.h>
#define NAT_HELPER_NAME "ftp"
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Rusty Russell <rusty@rustcorp.com.au>");
MODULE_DESCRIPTION("ftp NAT helper");
MODULE_ALIAS_NF_NAT_HELPER(NAT_HELPER_NAME);
/* FIXME: Time out? --RR */
static struct nf_conntrack_nat_helper nat_helper_ftp =
NF_CT_NAT_HELPER_INIT(NAT_HELPER_NAME);
static int nf_nat_ftp_fmt_cmd(struct nf_conn *ct, enum nf_ct_ftp_type type,
char *buffer, size_t buflen,
union nf_inet_addr *addr, u16 port)
{
switch (type) {
case NF_CT_FTP_PORT:
case NF_CT_FTP_PASV:
return snprintf(buffer, buflen, "%u,%u,%u,%u,%u,%u",
((unsigned char *)&addr->ip)[0],
((unsigned char *)&addr->ip)[1],
((unsigned char *)&addr->ip)[2],
((unsigned char *)&addr->ip)[3],
port >> 8,
port & 0xFF);
case NF_CT_FTP_EPRT:
if (nf_ct_l3num(ct) == NFPROTO_IPV4)
return snprintf(buffer, buflen, "|1|%pI4|%u|",
&addr->ip, port);
else
return snprintf(buffer, buflen, "|2|%pI6|%u|",
&addr->ip6, port);
case NF_CT_FTP_EPSV:
return snprintf(buffer, buflen, "|||%u|", port);
}
return 0;
}
/* So, this packet has hit the connection tracking matching code.
Mangle it, and change the expectation to match the new version. */
static unsigned int nf_nat_ftp(struct sk_buff *skb,
enum ip_conntrack_info ctinfo,
enum nf_ct_ftp_type type,
unsigned int protoff,
unsigned int matchoff,
unsigned int matchlen,
struct nf_conntrack_expect *exp)
{
union nf_inet_addr newaddr;
u_int16_t port;
int dir = CTINFO2DIR(ctinfo);
struct nf_conn *ct = exp->master;
char buffer[sizeof("|1||65535|") + INET6_ADDRSTRLEN];
unsigned int buflen;
pr_debug("type %i, off %u len %u\n", type, matchoff, matchlen);
/* Connection will come from wherever this packet goes, hence !dir */
newaddr = ct->tuplehash[!dir].tuple.dst.u3;
exp->saved_proto.tcp.port = exp->tuple.dst.u.tcp.port;
exp->dir = !dir;
/* When you see the packet, we need to NAT it the same as the
* this one. */
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, exp->master, "all ports in use");
return NF_DROP;
}
buflen = nf_nat_ftp_fmt_cmd(ct, type, buffer, sizeof(buffer),
&newaddr, port);
if (!buflen)
goto out;
pr_debug("calling nf_nat_mangle_tcp_packet\n");
if (!nf_nat_mangle_tcp_packet(skb, ct, ctinfo, protoff, matchoff,
matchlen, buffer, buflen))
goto out;
return NF_ACCEPT;
out:
nf_ct_helper_log(skb, ct, "cannot mangle packet");
nf_ct_unexpect_related(exp);
return NF_DROP;
}
static void __exit nf_nat_ftp_fini(void)
{
nf_nat_helper_unregister(&nat_helper_ftp);
RCU_INIT_POINTER(nf_nat_ftp_hook, NULL);
synchronize_rcu();
}
static int __init nf_nat_ftp_init(void)
{
BUG_ON(nf_nat_ftp_hook != NULL);
nf_nat_helper_register(&nat_helper_ftp);
RCU_INIT_POINTER(nf_nat_ftp_hook, nf_nat_ftp);
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_ftp_init);
module_exit(nf_nat_ftp_fini);