static int ip6_tnl_rcv(struct sk_buff *skb, __u16 protocol,
__u8 ipproto,
void (*dscp_ecn_decapsulate)(struct ip6_tnl *t,
struct ipv6hdr *ipv6h,
struct sk_buff *skb))
{
struct ip6_tnl *t;
struct ipv6hdr *ipv6h = ipv6_hdr(skb);
read_lock(&ip6_tnl_lock);
if ((t = ip6_tnl_lookup(dev_net(skb->dev), &ipv6h->saddr,
&ipv6h->daddr)) != NULL) {
if (t->parms.proto != ipproto && t->parms.proto != 0) {
read_unlock(&ip6_tnl_lock);
goto discard;
}
if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) {
read_unlock(&ip6_tnl_lock);
goto discard;
}
if (!ip6_tnl_rcv_ctl(t)) {
t->dev->stats.rx_dropped++;
read_unlock(&ip6_tnl_lock);
goto discard;
}
secpath_reset(skb);
skb->mac_header = skb->network_header;
skb_reset_network_header(skb);
skb->protocol = htons(protocol);
skb->pkt_type = PACKET_HOST;
memset(skb->cb, 0, sizeof(struct inet6_skb_parm));
skb->dev = t->dev;
dst_release(skb->dst);
skb->dst = NULL;
nf_reset(skb);
dscp_ecn_decapsulate(t, ipv6h, skb);
t->dev->stats.rx_packets++;
t->dev->stats.rx_bytes += skb->len;
netif_rx(skb);
read_unlock(&ip6_tnl_lock);
return 0;
}
read_unlock(&ip6_tnl_lock);
return 1;
discard:
kfree_skb(skb);
return 0;
}
static int
ip6_tnl_err(struct sk_buff *skb, __u8 ipproto, struct inet6_skb_parm *opt,
u8 *type, u8 *code, int *msg, __u32 *info, int offset)
{
struct ipv6hdr *ipv6h = (struct ipv6hdr *) skb->data;
struct ip6_tnl *t;
int rel_msg = 0;
u8 rel_type = ICMPV6_DEST_UNREACH;
u8 rel_code = ICMPV6_ADDR_UNREACH;
__u32 rel_info = 0;
__u16 len;
int err = -ENOENT;
/* If the packet doesn't contain the original IPv6 header we are
in trouble since we might need the source address for further
processing of the error. */
read_lock(&ip6_tnl_lock);
if ((t = ip6_tnl_lookup(dev_net(skb->dev), &ipv6h->daddr,
&ipv6h->saddr)) == NULL)
goto out;
if (t->parms.proto != ipproto && t->parms.proto != 0)
goto out;
err = 0;
switch (*type) {
__u32 teli;
struct ipv6_tlv_tnl_enc_lim *tel;
__u32 mtu;
case ICMPV6_DEST_UNREACH:
if (net_ratelimit())
printk(KERN_WARNING
"%s: Path to destination invalid "
"or inactive!\n", t->parms.name);
rel_msg = 1;
break;
case ICMPV6_TIME_EXCEED:
if ((*code) == ICMPV6_EXC_HOPLIMIT) {
if (net_ratelimit())
printk(KERN_WARNING
"%s: Too small hop limit or "
"routing loop in tunnel!\n",
t->parms.name);
rel_msg = 1;
}
break;
case ICMPV6_PARAMPROB:
teli = 0;
if ((*code) == ICMPV6_HDR_FIELD)
teli = parse_tlv_tnl_enc_lim(skb, skb->data);
if (teli && teli == *info - 2) {
tel = (struct ipv6_tlv_tnl_enc_lim *) &skb->data[teli];
if (tel->encap_limit == 0) {
if (net_ratelimit())
printk(KERN_WARNING
"%s: Too small encapsulation "
"limit or routing loop in "
"tunnel!\n", t->parms.name);
rel_msg = 1;
}
} else if (net_ratelimit()) {
printk(KERN_WARNING
"%s: Recipient unable to parse tunneled "
"packet!\n ", t->parms.name);
}
break;
case ICMPV6_PKT_TOOBIG:
mtu = *info - offset;
if (mtu < IPV6_MIN_MTU)
mtu = IPV6_MIN_MTU;
t->dev->mtu = mtu;
if ((len = sizeof (*ipv6h) + ntohs(ipv6h->payload_len)) > mtu) {
rel_type = ICMPV6_PKT_TOOBIG;
rel_code = 0;
rel_info = mtu;
rel_msg = 1;
}
break;
}
*type = rel_type;
*code = rel_code;
*info = rel_info;
*msg = rel_msg;
out:
read_unlock(&ip6_tnl_lock);
return err;
}