104 lines
2.2 KiB
C
104 lines
2.2 KiB
C
#include <linux/errno.h>
|
|
#include <linux/ip.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/module.h>
|
|
#include <linux/skbuff.h>
|
|
#include <linux/socket.h>
|
|
#include <linux/types.h>
|
|
#include <net/checksum.h>
|
|
#include <net/ip.h>
|
|
#include <net/ip6_fib.h>
|
|
#include <net/lwtunnel.h>
|
|
#include <net/protocol.h>
|
|
#include <uapi/linux/ila.h>
|
|
#include "ila.h"
|
|
|
|
static __wsum get_csum_diff(struct ipv6hdr *ip6h, struct ila_params *p)
|
|
{
|
|
if (*(__be64 *)&ip6h->daddr == p->locator_match)
|
|
return p->csum_diff;
|
|
else
|
|
return compute_csum_diff8((__be32 *)&ip6h->daddr,
|
|
(__be32 *)&p->locator);
|
|
}
|
|
|
|
void update_ipv6_locator(struct sk_buff *skb, struct ila_params *p)
|
|
{
|
|
__wsum diff;
|
|
struct ipv6hdr *ip6h = ipv6_hdr(skb);
|
|
size_t nhoff = sizeof(struct ipv6hdr);
|
|
|
|
/* First update checksum */
|
|
switch (ip6h->nexthdr) {
|
|
case NEXTHDR_TCP:
|
|
if (likely(pskb_may_pull(skb, nhoff + sizeof(struct tcphdr)))) {
|
|
struct tcphdr *th = (struct tcphdr *)
|
|
(skb_network_header(skb) + nhoff);
|
|
|
|
diff = get_csum_diff(ip6h, p);
|
|
inet_proto_csum_replace_by_diff(&th->check, skb,
|
|
diff, true);
|
|
}
|
|
break;
|
|
case NEXTHDR_UDP:
|
|
if (likely(pskb_may_pull(skb, nhoff + sizeof(struct udphdr)))) {
|
|
struct udphdr *uh = (struct udphdr *)
|
|
(skb_network_header(skb) + nhoff);
|
|
|
|
if (uh->check || skb->ip_summed == CHECKSUM_PARTIAL) {
|
|
diff = get_csum_diff(ip6h, p);
|
|
inet_proto_csum_replace_by_diff(&uh->check, skb,
|
|
diff, true);
|
|
if (!uh->check)
|
|
uh->check = CSUM_MANGLED_0;
|
|
}
|
|
}
|
|
break;
|
|
case NEXTHDR_ICMP:
|
|
if (likely(pskb_may_pull(skb,
|
|
nhoff + sizeof(struct icmp6hdr)))) {
|
|
struct icmp6hdr *ih = (struct icmp6hdr *)
|
|
(skb_network_header(skb) + nhoff);
|
|
|
|
diff = get_csum_diff(ip6h, p);
|
|
inet_proto_csum_replace_by_diff(&ih->icmp6_cksum, skb,
|
|
diff, true);
|
|
}
|
|
break;
|
|
}
|
|
|
|
/* Now change destination address */
|
|
*(__be64 *)&ip6h->daddr = p->locator;
|
|
}
|
|
|
|
static int __init ila_init(void)
|
|
{
|
|
int ret;
|
|
|
|
ret = ila_lwt_init();
|
|
|
|
if (ret)
|
|
goto fail_lwt;
|
|
|
|
ret = ila_xlat_init();
|
|
if (ret)
|
|
goto fail_xlat;
|
|
|
|
return 0;
|
|
fail_xlat:
|
|
ila_lwt_fini();
|
|
fail_lwt:
|
|
return ret;
|
|
}
|
|
|
|
static void __exit ila_fini(void)
|
|
{
|
|
ila_xlat_fini();
|
|
ila_lwt_fini();
|
|
}
|
|
|
|
module_init(ila_init);
|
|
module_exit(ila_fini);
|
|
MODULE_AUTHOR("Tom Herbert <tom@herbertland.com>");
|
|
MODULE_LICENSE("GPL");
|