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/secure_seq.h>
16 #include <net/netfilter/nf_nat.h>
17 #include <net/netfilter/nf_nat_core.h>
18 #include <net/netfilter/nf_nat_rule.h>
19 #include <net/netfilter/nf_nat_protocol.h>
21 bool nf_nat_proto_in_range(const struct nf_conntrack_tuple
*tuple
,
22 enum nf_nat_manip_type maniptype
,
23 const union nf_conntrack_man_proto
*min
,
24 const union nf_conntrack_man_proto
*max
)
28 if (maniptype
== IP_NAT_MANIP_SRC
)
29 port
= tuple
->src
.u
.all
;
31 port
= tuple
->dst
.u
.all
;
33 return ntohs(port
) >= ntohs(min
->all
) &&
34 ntohs(port
) <= ntohs(max
->all
);
36 EXPORT_SYMBOL_GPL(nf_nat_proto_in_range
);
38 void nf_nat_proto_unique_tuple(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
== IP_NAT_MANIP_SRC
)
49 portptr
= &tuple
->src
.u
.all
;
51 portptr
= &tuple
->dst
.u
.all
;
53 /* If no range specified... */
54 if (!(range
->flags
& IP_NAT_RANGE_PROTO_SPECIFIED
)) {
55 /* If it's dst rewrite, can't change port */
56 if (maniptype
== IP_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
.all
);
74 range_size
= ntohs(range
->max
.all
) - min
+ 1;
77 if (range
->flags
& IP_NAT_RANGE_PROTO_RANDOM
)
78 off
= secure_ipv4_port_ephemeral(tuple
->src
.u3
.ip
, tuple
->dst
.u3
.ip
,
79 maniptype
== IP_NAT_MANIP_SRC
85 for (i
= 0; ; ++off
) {
86 *portptr
= htons(min
+ off
% range_size
);
87 if (++i
!= range_size
&& nf_nat_used_tuple(tuple
, ct
))
89 if (!(range
->flags
& IP_NAT_RANGE_PROTO_RANDOM
))
95 EXPORT_SYMBOL_GPL(nf_nat_proto_unique_tuple
);
97 #if defined(CONFIG_NF_CT_NETLINK) || defined(CONFIG_NF_CT_NETLINK_MODULE)
98 int nf_nat_proto_range_to_nlattr(struct sk_buff
*skb
,
99 const struct nf_nat_range
*range
)
101 NLA_PUT_BE16(skb
, CTA_PROTONAT_PORT_MIN
, range
->min
.all
);
102 NLA_PUT_BE16(skb
, CTA_PROTONAT_PORT_MAX
, range
->max
.all
);
108 EXPORT_SYMBOL_GPL(nf_nat_proto_nlattr_to_range
);
110 int nf_nat_proto_nlattr_to_range(struct nlattr
*tb
[],
111 struct nf_nat_range
*range
)
113 if (tb
[CTA_PROTONAT_PORT_MIN
]) {
114 range
->min
.all
= nla_get_be16(tb
[CTA_PROTONAT_PORT_MIN
]);
115 range
->max
.all
= range
->min
.tcp
.port
;
116 range
->flags
|= IP_NAT_RANGE_PROTO_SPECIFIED
;
118 if (tb
[CTA_PROTONAT_PORT_MAX
]) {
119 range
->max
.all
= nla_get_be16(tb
[CTA_PROTONAT_PORT_MAX
]);
120 range
->flags
|= IP_NAT_RANGE_PROTO_SPECIFIED
;
124 EXPORT_SYMBOL_GPL(nf_nat_proto_range_to_nlattr
);