[IPV6]: Allow to replace skbuff by TLV parser.
In receiving Mobile IPv6 home address option which is a TLV carried by
destination options header, kernel will try to mangle source adderss
of packet. Think of cloned skbuff it is required to replace it by the
parser just like routing header case.
This is a framework to achieve that to allow TLV parser to replace
inbound skbuff pointer.
Signed-off-by: Masahide NAKAMURA <nakam@linux-ipv6.org>
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv6/exthdrs.c b/net/ipv6/exthdrs.c
index 50ff49e..1cdd0f0 100644
--- a/net/ipv6/exthdrs.c
+++ b/net/ipv6/exthdrs.c
@@ -102,7 +102,7 @@
struct tlvtype_proc {
int type;
- int (*func)(struct sk_buff *skb, int offset);
+ int (*func)(struct sk_buff **skbp, int offset);
};
/*********************
@@ -111,8 +111,10 @@
/* An unknown option is detected, decide what to do */
-static int ip6_tlvopt_unknown(struct sk_buff *skb, int optoff)
+static int ip6_tlvopt_unknown(struct sk_buff **skbp, int optoff)
{
+ struct sk_buff *skb = *skbp;
+
switch ((skb->nh.raw[optoff] & 0xC0) >> 6) {
case 0: /* ignore */
return 1;
@@ -137,8 +139,9 @@
/* Parse tlv encoded option header (hop-by-hop or destination) */
-static int ip6_parse_tlv(struct tlvtype_proc *procs, struct sk_buff *skb)
+static int ip6_parse_tlv(struct tlvtype_proc *procs, struct sk_buff **skbp)
{
+ struct sk_buff *skb = *skbp;
struct tlvtype_proc *curr;
int off = skb->h.raw - skb->nh.raw;
int len = ((skb->h.raw[1]+1)<<3);
@@ -168,13 +171,13 @@
/* type specific length/alignment
checks will be performed in the
func(). */
- if (curr->func(skb, off) == 0)
+ if (curr->func(skbp, off) == 0)
return 0;
break;
}
}
if (curr->type < 0) {
- if (ip6_tlvopt_unknown(skb, off) == 0)
+ if (ip6_tlvopt_unknown(skbp, off) == 0)
return 0;
}
break;
@@ -213,7 +216,8 @@
opt->lastopt = skb->h.raw - skb->nh.raw;
opt->dst1 = skb->h.raw - skb->nh.raw;
- if (ip6_parse_tlv(tlvprocdestopt_lst, skb)) {
+ if (ip6_parse_tlv(tlvprocdestopt_lst, skbp)) {
+ skb = *skbp;
skb->h.raw += ((skb->h.raw[1]+1)<<3);
opt->nhoff = opt->dst1;
return 1;
@@ -517,8 +521,10 @@
/* Router Alert as of RFC 2711 */
-static int ipv6_hop_ra(struct sk_buff *skb, int optoff)
+static int ipv6_hop_ra(struct sk_buff **skbp, int optoff)
{
+ struct sk_buff *skb = *skbp;
+
if (skb->nh.raw[optoff+1] == 2) {
IP6CB(skb)->ra = optoff;
return 1;
@@ -531,8 +537,9 @@
/* Jumbo payload */
-static int ipv6_hop_jumbo(struct sk_buff *skb, int optoff)
+static int ipv6_hop_jumbo(struct sk_buff **skbp, int optoff)
{
+ struct sk_buff *skb = *skbp;
u32 pkt_len;
if (skb->nh.raw[optoff+1] != 4 || (optoff&3) != 2) {
@@ -581,8 +588,9 @@
{ -1, }
};
-int ipv6_parse_hopopts(struct sk_buff *skb)
+int ipv6_parse_hopopts(struct sk_buff **skbp)
{
+ struct sk_buff *skb = *skbp;
struct inet6_skb_parm *opt = IP6CB(skb);
/*
@@ -598,7 +606,8 @@
}
opt->hop = sizeof(struct ipv6hdr);
- if (ip6_parse_tlv(tlvprochopopt_lst, skb)) {
+ if (ip6_parse_tlv(tlvprochopopt_lst, skbp)) {
+ skb = *skbp;
skb->h.raw += (skb->h.raw[1]+1)<<3;
opt->nhoff = sizeof(struct ipv6hdr);
return 1;