xfrm6: handling fragment
RFC4301 Section 7.1 says:
"7.1. Tunnel Mode SAs that Carry Initial and Non-Initial Fragments
All implementations MUST support tunnel mode SAs that are configured
to pass traffic without regard to port field (or ICMP type/code or
Mobility Header type) values. If the SA will carry traffic for
specified protocols, the selector set for the SA MUST specify the
port fields (or ICMP type/code or Mobility Header type) as ANY. An
SA defined in this fashion will carry all traffic including initial
and non-initial fragments for the indicated Local/Remote addresses
and specified Next Layer protocol(s)."
But for IPv6, fragment is treated as a protocol. This change catches
protocol transported in fragmented packet. In IPv4, there is no
problem.
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv6/xfrm6_policy.c b/net/ipv6/xfrm6_policy.c
index 08e4cbb..604bc0a 100644
--- a/net/ipv6/xfrm6_policy.c
+++ b/net/ipv6/xfrm6_policy.c
@@ -144,6 +144,7 @@
static inline void
_decode_session6(struct sk_buff *skb, struct flowi *fl, int reverse)
{
+ int onlyproto = 0;
u16 offset = skb_network_header_len(skb);
struct ipv6hdr *hdr = ipv6_hdr(skb);
struct ipv6_opt_hdr *exthdr;
@@ -159,6 +160,8 @@
exthdr = (struct ipv6_opt_hdr *)(nh + offset);
switch (nexthdr) {
+ case NEXTHDR_FRAGMENT:
+ onlyproto = 1;
case NEXTHDR_ROUTING:
case NEXTHDR_HOP:
case NEXTHDR_DEST:
@@ -172,7 +175,7 @@
case IPPROTO_TCP:
case IPPROTO_SCTP:
case IPPROTO_DCCP:
- if (pskb_may_pull(skb, nh + offset + 4 - skb->data)) {
+ if (!onlyproto && pskb_may_pull(skb, nh + offset + 4 - skb->data)) {
__be16 *ports = (__be16 *)exthdr;
fl->fl_ip_sport = ports[!!reverse];
@@ -182,7 +185,7 @@
return;
case IPPROTO_ICMPV6:
- if (pskb_may_pull(skb, nh + offset + 2 - skb->data)) {
+ if (!onlyproto && pskb_may_pull(skb, nh + offset + 2 - skb->data)) {
u8 *icmp = (u8 *)exthdr;
fl->fl_icmp_type = icmp[0];
@@ -193,7 +196,7 @@
#if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
case IPPROTO_MH:
- if (pskb_may_pull(skb, nh + offset + 3 - skb->data)) {
+ if (!onlyproto && pskb_may_pull(skb, nh + offset + 3 - skb->data)) {
struct ip6_mh *mh;
mh = (struct ip6_mh *)exthdr;