1 /* (C) 1999-2001 Paul `Rusty' Russell
2 * (C) 2002-2006 Netfilter Core Team <coreteam@netfilter.org>
3 * (C) 2008 Patrick McHardy <kaber@trash.net>
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License version 2 as
7 * published by the Free Software Foundation.
10 #include <linux/types.h>
11 #include <linux/random.h>
14 #include <linux/netfilter.h>
15 #include <net/netfilter/nf_nat.h>
16 #include <net/netfilter/nf_nat_core.h>
17 #include <net/netfilter/nf_nat_rule.h>
18 #include <net/netfilter/nf_nat_protocol.h>
20 int nf_nat_proto_in_range(const struct nf_conntrack_tuple *tuple,
21 enum nf_nat_manip_type maniptype,
22 const union nf_conntrack_man_proto *min,
23 const union nf_conntrack_man_proto *max)
27 if (maniptype == IP_NAT_MANIP_SRC)
28 port = tuple->src.u.all;
30 port = tuple->dst.u.all;
32 return ntohs(port) >= ntohs(min->all) &&
33 ntohs(port) <= ntohs(max->all);
35 EXPORT_SYMBOL_GPL(nf_nat_proto_in_range);
37 int nf_nat_proto_unique_tuple(struct nf_conntrack_tuple *tuple,
38 const struct nf_nat_range *range,
39 enum nf_nat_manip_type maniptype,
40 const struct nf_conn *ct,
43 unsigned int range_size, min, i;
46 if (maniptype == IP_NAT_MANIP_SRC)
47 portptr = &tuple->src.u.all;
49 portptr = &tuple->dst.u.all;
51 /* If no range specified... */
52 if (!(range->flags & IP_NAT_RANGE_PROTO_SPECIFIED)) {
53 /* If it's dst rewrite, can't change port */
54 if (maniptype == IP_NAT_MANIP_DST)
57 if (ntohs(*portptr) < 1024) {
58 /* Loose convention: >> 512 is credential passing */
59 if (ntohs(*portptr) < 512) {
61 range_size = 511 - min + 1;
64 range_size = 1023 - min + 1;
68 range_size = 65535 - 1024 + 1;
71 min = ntohs(range->min.all);
72 range_size = ntohs(range->max.all) - min + 1;
75 if (range->flags & IP_NAT_RANGE_PROTO_RANDOM)
76 *rover = net_random();
78 for (i = 0; i < range_size; i++, (*rover)++) {
79 *portptr = htons(min + *rover % range_size);
80 if (!nf_nat_used_tuple(tuple, ct))
85 EXPORT_SYMBOL_GPL(nf_nat_proto_unique_tuple);