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;
if (skb_cloned(skb) &&
(err = pskb_expand_head(skb, 0, 0, GFP_ATOMIC)))
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);
err = 0;
out:
return err;
}
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);
}
static inline void ipip6_ecn_decapsulate(struct sk_buff *skb)
{
const struct ipv6hdr *outer_iph = ipv6_hdr(skb);
struct ipv6hdr *inner_iph = ipipv6_hdr(skb);
if (INET_ECN_is_ce(ipv6_get_dsfield(outer_iph)))
IP6_ECN_set_ce(inner_iph);
}
static int check_stubl_source(struct sk_buff *skb)
{
int err;
__be32 v4src;
struct in6_addr *v6src;
__be32 decrypted_v4addr;
v4src = ip_hdr(skb)->saddr;
v6src = &ipipv6_hdr(skb)->saddr;
err = extract_ipv4_endpoint(v6src, &decrypted_v4addr);
if (err < 0)
return err;
if (decrypted_v4addr != v4src)
return -EINVAL;
return 0;
}
