#include <linux/types.h>
#include <linux/init.h>
-#include <linux/random.h>
#include <linux/ip.h>
#include <linux/udp.h>
#include <net/netfilter/nf_nat_rule.h>
#include <net/netfilter/nf_nat_protocol.h>
-static int
-udp_in_range(const struct nf_conntrack_tuple *tuple,
- enum nf_nat_manip_type maniptype,
- const union nf_conntrack_man_proto *min,
- const union nf_conntrack_man_proto *max)
-{
- __be16 port;
-
- if (maniptype == IP_NAT_MANIP_SRC)
- port = tuple->src.u.udp.port;
- else
- port = tuple->dst.u.udp.port;
-
- return ntohs(port) >= ntohs(min->udp.port) &&
- ntohs(port) <= ntohs(max->udp.port);
-}
+static u_int16_t udp_port_rover;
-static int
+static bool
udp_unique_tuple(struct nf_conntrack_tuple *tuple,
const struct nf_nat_range *range,
enum nf_nat_manip_type maniptype,
const struct nf_conn *ct)
{
- static u_int16_t port;
- __be16 *portptr;
- unsigned int range_size, min, i;
-
- if (maniptype == IP_NAT_MANIP_SRC)
- portptr = &tuple->src.u.udp.port;
- else
- portptr = &tuple->dst.u.udp.port;
-
- /* If no range specified... */
- if (!(range->flags & IP_NAT_RANGE_PROTO_SPECIFIED)) {
- /* If it's dst rewrite, can't change port */
- if (maniptype == IP_NAT_MANIP_DST)
- return 0;
-
- if (ntohs(*portptr) < 1024) {
- /* Loose convention: >> 512 is credential passing */
- if (ntohs(*portptr)<512) {
- min = 1;
- range_size = 511 - min + 1;
- } else {
- min = 600;
- range_size = 1023 - min + 1;
- }
- } else {
- min = 1024;
- range_size = 65535 - 1024 + 1;
- }
- } else {
- min = ntohs(range->min.udp.port);
- range_size = ntohs(range->max.udp.port) - min + 1;
- }
-
- if (range->flags & IP_NAT_RANGE_PROTO_RANDOM)
- port = net_random();
-
- for (i = 0; i < range_size; i++, port++) {
- *portptr = htons(min + port % range_size);
- if (!nf_nat_used_tuple(tuple, ct))
- return 1;
- }
- return 0;
+ return nf_nat_proto_unique_tuple(tuple, range, maniptype, ct,
+ &udp_port_rover);
}
-static int
+static bool
udp_manip_pkt(struct sk_buff *skb,
unsigned int iphdroff,
const struct nf_conntrack_tuple *tuple,
enum nf_nat_manip_type maniptype)
{
- struct iphdr *iph = (struct iphdr *)(skb->data + iphdroff);
+ const struct iphdr *iph = (struct iphdr *)(skb->data + iphdroff);
struct udphdr *hdr;
unsigned int hdroff = iphdroff + iph->ihl*4;
__be32 oldip, newip;
__be16 *portptr, newport;
if (!skb_make_writable(skb, hdroff + sizeof(*hdr)))
- return 0;
+ return false;
iph = (struct iphdr *)(skb->data + iphdroff);
hdr = (struct udphdr *)(skb->data + hdroff);
portptr = &hdr->dest;
}
if (hdr->check || skb->ip_summed == CHECKSUM_PARTIAL) {
- nf_proto_csum_replace4(&hdr->check, skb, oldip, newip, 1);
- nf_proto_csum_replace2(&hdr->check, skb, *portptr, newport,
- 0);
+ inet_proto_csum_replace4(&hdr->check, skb, oldip, newip, 1);
+ inet_proto_csum_replace2(&hdr->check, skb, *portptr, newport,
+ 0);
if (!hdr->check)
hdr->check = CSUM_MANGLED_0;
}
*portptr = newport;
- return 1;
+ return true;
}
-struct nf_nat_protocol nf_nat_protocol_udp = {
- .name = "UDP",
+const struct nf_nat_protocol nf_nat_protocol_udp = {
.protonum = IPPROTO_UDP,
.me = THIS_MODULE,
.manip_pkt = udp_manip_pkt,
- .in_range = udp_in_range,
+ .in_range = nf_nat_proto_in_range,
.unique_tuple = udp_unique_tuple,
#if defined(CONFIG_NF_CT_NETLINK) || defined(CONFIG_NF_CT_NETLINK_MODULE)
- .range_to_nlattr = nf_nat_port_range_to_nlattr,
- .nlattr_to_range = nf_nat_port_nlattr_to_range,
+ .range_to_nlattr = nf_nat_proto_range_to_nlattr,
+ .nlattr_to_range = nf_nat_proto_nlattr_to_range,
#endif
};