151 lines
3.9 KiB
C
151 lines
3.9 KiB
C
/*
|
|
* xfrm6_mode_tunnel.c - Tunnel mode encapsulation for IPv6.
|
|
*
|
|
* Copyright (C) 2002 USAGI/WIDE Project
|
|
* Copyright (c) 2004-2006 Herbert Xu <herbert@gondor.apana.org.au>
|
|
*/
|
|
|
|
#include <linux/gfp.h>
|
|
#include <linux/init.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/module.h>
|
|
#include <linux/skbuff.h>
|
|
#include <linux/stringify.h>
|
|
#include <net/dsfield.h>
|
|
#include <net/dst.h>
|
|
#include <net/inet_ecn.h>
|
|
#include <net/ip6_route.h>
|
|
#include <net/ipv6.h>
|
|
#include <net/xfrm.h>
|
|
|
|
static inline void ipip6_ecn_decapsulate(struct sk_buff *skb)
|
|
{
|
|
struct ipv6hdr *inner_iph = ipipv6_hdr(skb);
|
|
|
|
if (INET_ECN_is_ce(XFRM_MODE_SKB_CB(skb)->tos))
|
|
IP6_ECN_set_ce(skb, inner_iph);
|
|
}
|
|
|
|
/* Add encapsulation header.
|
|
*
|
|
* The top IP header will be constructed per RFC 2401.
|
|
*/
|
|
static int xfrm6_mode_tunnel_output(struct xfrm_state *x, struct sk_buff *skb)
|
|
{
|
|
struct dst_entry *dst = skb_dst(skb);
|
|
struct ipv6hdr *top_iph;
|
|
int dsfield;
|
|
|
|
skb_set_inner_network_header(skb, skb_network_offset(skb));
|
|
skb_set_inner_transport_header(skb, skb_transport_offset(skb));
|
|
|
|
skb_set_network_header(skb, -x->props.header_len);
|
|
skb->mac_header = skb->network_header +
|
|
offsetof(struct ipv6hdr, nexthdr);
|
|
skb->transport_header = skb->network_header + sizeof(*top_iph);
|
|
top_iph = ipv6_hdr(skb);
|
|
|
|
top_iph->version = 6;
|
|
|
|
memcpy(top_iph->flow_lbl, XFRM_MODE_SKB_CB(skb)->flow_lbl,
|
|
sizeof(top_iph->flow_lbl));
|
|
top_iph->nexthdr = xfrm_af2proto(skb_dst(skb)->ops->family);
|
|
|
|
if (x->props.extra_flags & XFRM_SA_XFLAG_DONT_ENCAP_DSCP)
|
|
dsfield = 0;
|
|
else
|
|
dsfield = XFRM_MODE_SKB_CB(skb)->tos;
|
|
dsfield = INET_ECN_encapsulate(dsfield, XFRM_MODE_SKB_CB(skb)->tos);
|
|
if (x->props.flags & XFRM_STATE_NOECN)
|
|
dsfield &= ~INET_ECN_MASK;
|
|
ipv6_change_dsfield(top_iph, 0, dsfield);
|
|
top_iph->hop_limit = ip6_dst_hoplimit(xfrm_dst_child(dst));
|
|
top_iph->saddr = *(struct in6_addr *)&x->props.saddr;
|
|
top_iph->daddr = *(struct in6_addr *)&x->id.daddr;
|
|
return 0;
|
|
}
|
|
|
|
#define for_each_input_rcu(head, handler) \
|
|
for (handler = rcu_dereference(head); \
|
|
handler != NULL; \
|
|
handler = rcu_dereference(handler->next))
|
|
|
|
|
|
static int xfrm6_mode_tunnel_input(struct xfrm_state *x, struct sk_buff *skb)
|
|
{
|
|
int err = -EINVAL;
|
|
|
|
if (XFRM_MODE_SKB_CB(skb)->protocol != IPPROTO_IPV6)
|
|
goto out;
|
|
if (!pskb_may_pull(skb, sizeof(struct ipv6hdr)))
|
|
goto out;
|
|
|
|
err = skb_unclone(skb, GFP_ATOMIC);
|
|
if (err)
|
|
goto out;
|
|
|
|
if (x->props.flags & XFRM_STATE_DECAP_DSCP)
|
|
ipv6_copy_dscp(ipv6_get_dsfield(ipv6_hdr(skb)),
|
|
ipipv6_hdr(skb));
|
|
if (!(x->props.flags & XFRM_STATE_NOECN))
|
|
ipip6_ecn_decapsulate(skb);
|
|
|
|
skb_reset_network_header(skb);
|
|
skb_mac_header_rebuild(skb);
|
|
eth_hdr(skb)->h_proto = skb->protocol;
|
|
|
|
err = 0;
|
|
|
|
out:
|
|
return err;
|
|
}
|
|
|
|
static struct sk_buff *xfrm6_mode_tunnel_gso_segment(struct xfrm_state *x,
|
|
struct sk_buff *skb,
|
|
netdev_features_t features)
|
|
{
|
|
__skb_push(skb, skb->mac_len);
|
|
return skb_mac_gso_segment(skb, features);
|
|
}
|
|
|
|
static void xfrm6_mode_tunnel_xmit(struct xfrm_state *x, struct sk_buff *skb)
|
|
{
|
|
struct xfrm_offload *xo = xfrm_offload(skb);
|
|
|
|
if (xo->flags & XFRM_GSO_SEGMENT)
|
|
skb->transport_header = skb->network_header + sizeof(struct ipv6hdr);
|
|
|
|
skb_reset_mac_len(skb);
|
|
pskb_pull(skb, skb->mac_len + x->props.header_len);
|
|
}
|
|
|
|
static struct xfrm_mode xfrm6_tunnel_mode = {
|
|
.input2 = xfrm6_mode_tunnel_input,
|
|
.input = xfrm_prepare_input,
|
|
.output2 = xfrm6_mode_tunnel_output,
|
|
.output = xfrm6_prepare_output,
|
|
.gso_segment = xfrm6_mode_tunnel_gso_segment,
|
|
.xmit = xfrm6_mode_tunnel_xmit,
|
|
.owner = THIS_MODULE,
|
|
.encap = XFRM_MODE_TUNNEL,
|
|
.flags = XFRM_MODE_FLAG_TUNNEL,
|
|
};
|
|
|
|
static int __init xfrm6_mode_tunnel_init(void)
|
|
{
|
|
return xfrm_register_mode(&xfrm6_tunnel_mode, AF_INET6);
|
|
}
|
|
|
|
static void __exit xfrm6_mode_tunnel_exit(void)
|
|
{
|
|
int err;
|
|
|
|
err = xfrm_unregister_mode(&xfrm6_tunnel_mode, AF_INET6);
|
|
BUG_ON(err);
|
|
}
|
|
|
|
module_init(xfrm6_mode_tunnel_init);
|
|
module_exit(xfrm6_mode_tunnel_exit);
|
|
MODULE_LICENSE("GPL");
|
|
MODULE_ALIAS_XFRM_MODE(AF_INET6, XFRM_MODE_TUNNEL);
|