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>
12 #include <linux/netfilter.h>
13 #include <linux/export.h>
15 #include <net/netfilter/nf_nat.h>
16 #include <net/netfilter/nf_nat_core.h>
17 #include <net/netfilter/nf_nat_l3proto.h>
18 #include <net/netfilter/nf_nat_l4proto.h>
20 bool nf_nat_l4proto_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
== NF_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_l4proto_in_range
);
37 void nf_nat_l4proto_unique_tuple(const struct nf_nat_l3proto
*l3proto
,
38 struct nf_conntrack_tuple
*tuple
,
39 const struct nf_nat_range
*range
,
40 enum nf_nat_manip_type maniptype
,
41 const struct nf_conn
*ct
,
44 unsigned int range_size
, min
, i
;
48 if (maniptype
== NF_NAT_MANIP_SRC
)
49 portptr
= &tuple
->src
.u
.all
;
51 portptr
= &tuple
->dst
.u
.all
;
53 /* If no range specified... */
54 if (!(range
->flags
& NF_NAT_RANGE_PROTO_SPECIFIED
)) {
55 /* If it's dst rewrite, can't change port */
56 if (maniptype
== NF_NAT_MANIP_DST
)
59 if (ntohs(*portptr
) < 1024) {
60 /* Loose convention: >> 512 is credential passing */
61 if (ntohs(*portptr
) < 512) {
63 range_size
= 511 - min
+ 1;
66 range_size
= 1023 - min
+ 1;
70 range_size
= 65535 - 1024 + 1;
73 min
= ntohs(range
->min_proto
.all
);
74 range_size
= ntohs(range
->max_proto
.all
) - min
+ 1;
77 if (range
->flags
& NF_NAT_RANGE_PROTO_RANDOM
) {
78 off
= l3proto
->secure_port(tuple
, maniptype
== NF_NAT_MANIP_SRC
81 } else if (range
->flags
& NF_NAT_RANGE_PROTO_RANDOM_FULLY
) {
87 for (i
= 0; ; ++off
) {
88 *portptr
= htons(min
+ off
% range_size
);
89 if (++i
!= range_size
&& nf_nat_used_tuple(tuple
, ct
))
91 if (!(range
->flags
& NF_NAT_RANGE_PROTO_RANDOM_ALL
))
96 EXPORT_SYMBOL_GPL(nf_nat_l4proto_unique_tuple
);
98 #if IS_ENABLED(CONFIG_NF_CT_NETLINK)
99 int nf_nat_l4proto_nlattr_to_range(struct nlattr
*tb
[],
100 struct nf_nat_range
*range
)
102 if (tb
[CTA_PROTONAT_PORT_MIN
]) {
103 range
->min_proto
.all
= nla_get_be16(tb
[CTA_PROTONAT_PORT_MIN
]);
104 range
->max_proto
.all
= range
->min_proto
.all
;
105 range
->flags
|= NF_NAT_RANGE_PROTO_SPECIFIED
;
107 if (tb
[CTA_PROTONAT_PORT_MAX
]) {
108 range
->max_proto
.all
= nla_get_be16(tb
[CTA_PROTONAT_PORT_MAX
]);
109 range
->flags
|= NF_NAT_RANGE_PROTO_SPECIFIED
;
113 EXPORT_SYMBOL_GPL(nf_nat_l4proto_nlattr_to_range
);