122 строки
3.3 KiB
C
122 строки
3.3 KiB
C
/*
|
|
* xfrm6_mode_transport.c - Transport mode encapsulation for IPv6.
|
|
*
|
|
* Copyright (C) 2002 USAGI/WIDE Project
|
|
* Copyright (c) 2004-2006 Herbert Xu <herbert@gondor.apana.org.au>
|
|
*/
|
|
|
|
#include <linux/init.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/module.h>
|
|
#include <linux/skbuff.h>
|
|
#include <linux/stringify.h>
|
|
#include <net/dst.h>
|
|
#include <net/ipv6.h>
|
|
#include <net/xfrm.h>
|
|
#include <net/protocol.h>
|
|
|
|
/* Add encapsulation header.
|
|
*
|
|
* The IP header and mutable extension headers will be moved forward to make
|
|
* space for the encapsulation header.
|
|
*/
|
|
static int xfrm6_transport_output(struct xfrm_state *x, struct sk_buff *skb)
|
|
{
|
|
struct ipv6hdr *iph;
|
|
u8 *prevhdr;
|
|
int hdr_len;
|
|
|
|
iph = ipv6_hdr(skb);
|
|
skb_set_inner_transport_header(skb, skb_transport_offset(skb));
|
|
|
|
hdr_len = x->type->hdr_offset(x, skb, &prevhdr);
|
|
skb_set_mac_header(skb, (prevhdr - x->props.header_len) - skb->data);
|
|
skb_set_network_header(skb, -x->props.header_len);
|
|
skb->transport_header = skb->network_header + hdr_len;
|
|
__skb_pull(skb, hdr_len);
|
|
memmove(ipv6_hdr(skb), iph, hdr_len);
|
|
return 0;
|
|
}
|
|
|
|
/* Remove encapsulation header.
|
|
*
|
|
* The IP header will be moved over the top of the encapsulation header.
|
|
*
|
|
* On entry, skb->h shall point to where the IP header should be and skb->nh
|
|
* shall be set to where the IP header currently is. skb->data shall point
|
|
* to the start of the payload.
|
|
*/
|
|
static int xfrm6_transport_input(struct xfrm_state *x, struct sk_buff *skb)
|
|
{
|
|
int ihl = skb->data - skb_transport_header(skb);
|
|
struct xfrm_offload *xo = xfrm_offload(skb);
|
|
|
|
if (skb->transport_header != skb->network_header) {
|
|
memmove(skb_transport_header(skb),
|
|
skb_network_header(skb), ihl);
|
|
skb->network_header = skb->transport_header;
|
|
}
|
|
ipv6_hdr(skb)->payload_len = htons(skb->len + ihl -
|
|
sizeof(struct ipv6hdr));
|
|
if (!xo || !(xo->flags & XFRM_GRO))
|
|
skb_reset_transport_header(skb);
|
|
return 0;
|
|
}
|
|
|
|
static struct sk_buff *xfrm4_transport_gso_segment(struct xfrm_state *x,
|
|
struct sk_buff *skb,
|
|
netdev_features_t features)
|
|
{
|
|
const struct net_offload *ops;
|
|
struct sk_buff *segs = ERR_PTR(-EINVAL);
|
|
struct xfrm_offload *xo = xfrm_offload(skb);
|
|
|
|
skb->transport_header += x->props.header_len;
|
|
ops = rcu_dereference(inet6_offloads[xo->proto]);
|
|
if (likely(ops && ops->callbacks.gso_segment))
|
|
segs = ops->callbacks.gso_segment(skb, features);
|
|
|
|
return segs;
|
|
}
|
|
|
|
static void xfrm6_transport_xmit(struct xfrm_state *x, struct sk_buff *skb)
|
|
{
|
|
struct xfrm_offload *xo = xfrm_offload(skb);
|
|
|
|
skb_reset_mac_len(skb);
|
|
pskb_pull(skb, skb->mac_len + sizeof(struct ipv6hdr) + x->props.header_len);
|
|
|
|
if (xo->flags & XFRM_GSO_SEGMENT) {
|
|
skb_reset_transport_header(skb);
|
|
skb->transport_header -= x->props.header_len;
|
|
}
|
|
}
|
|
|
|
|
|
static struct xfrm_mode xfrm6_transport_mode = {
|
|
.input = xfrm6_transport_input,
|
|
.output = xfrm6_transport_output,
|
|
.gso_segment = xfrm4_transport_gso_segment,
|
|
.xmit = xfrm6_transport_xmit,
|
|
.owner = THIS_MODULE,
|
|
.encap = XFRM_MODE_TRANSPORT,
|
|
};
|
|
|
|
static int __init xfrm6_transport_init(void)
|
|
{
|
|
return xfrm_register_mode(&xfrm6_transport_mode, AF_INET6);
|
|
}
|
|
|
|
static void __exit xfrm6_transport_exit(void)
|
|
{
|
|
int err;
|
|
|
|
err = xfrm_unregister_mode(&xfrm6_transport_mode, AF_INET6);
|
|
BUG_ON(err);
|
|
}
|
|
|
|
module_init(xfrm6_transport_init);
|
|
module_exit(xfrm6_transport_exit);
|
|
MODULE_LICENSE("GPL");
|
|
MODULE_ALIAS_XFRM_MODE(AF_INET6, XFRM_MODE_TRANSPORT);
|