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authorIlpo Järvinen <ilpo.jarvinen@helsinki.fi>2008-12-16 01:15:11 -0800
committerDavid S. Miller <davem@davemloft.net>2008-12-16 01:15:11 -0800
commitb1879204dda06a92a4ff55b681c99ee185180003 (patch)
tree3045f326dcff6bb1ca3768803bfc62e98e69c6dc /net/ipv4/ipmr.c
parentc40cf519f0c0f0cb0579d853949ef517a8bb494d (diff)
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ipmr: merge common code
Also removes redundant skb->len < x check which can't be true once pskb_may_pull(skb, x) succeeded. $ diff-funcs pim_rcv ipmr.c ipmr.c pim_rcv_v1 --- ipmr.c:pim_rcv() +++ ipmr.c:pim_rcv_v1() @@ -1,22 +1,27 @@ -static int pim_rcv(struct sk_buff * skb) +int pim_rcv_v1(struct sk_buff * skb) { - struct pimreghdr *pim; + struct igmphdr *pim; struct iphdr *encap; struct net_device *reg_dev = NULL; if (!pskb_may_pull(skb, sizeof(*pim) + sizeof(*encap))) goto drop; - pim = (struct pimreghdr *)skb_transport_header(skb); - if (pim->type != ((PIM_VERSION<<4)|(PIM_REGISTER)) || - (pim->flags&PIM_NULL_REGISTER) || - (ip_compute_csum((void *)pim, sizeof(*pim)) != 0 && - csum_fold(skb_checksum(skb, 0, skb->len, 0)))) + pim = igmp_hdr(skb); + + if (!mroute_do_pim || + skb->len < sizeof(*pim) + sizeof(*encap) || + pim->group != PIM_V1_VERSION || pim->code != PIM_V1_REGISTER) goto drop; - /* check if the inner packet is destined to mcast group */ encap = (struct iphdr *)(skb_transport_header(skb) + - sizeof(struct pimreghdr)); + sizeof(struct igmphdr)); + /* + Check that: + a. packet is really destinted to a multicast group + b. packet is not a NULL-REGISTER + c. packet is not truncated + */ if (!ipv4_is_multicast(encap->daddr) || encap->tot_len == 0 || ntohs(encap->tot_len) + sizeof(*pim) > skb->len) @@ -40,9 +45,9 @@ skb->ip_summed = 0; skb->pkt_type = PACKET_HOST; dst_release(skb->dst); + skb->dst = NULL; reg_dev->stats.rx_bytes += skb->len; reg_dev->stats.rx_packets++; - skb->dst = NULL; nf_reset(skb); netif_rx(skb); dev_put(reg_dev); $ codiff net/ipv4/ipmr.o.old net/ipv4/ipmr.o.new net/ipv4/ipmr.c: pim_rcv_v1 | -283 pim_rcv | -284 2 functions changed, 567 bytes removed net/ipv4/ipmr.c: __pim_rcv | +307 1 function changed, 307 bytes added net/ipv4/ipmr.o.new: 3 functions changed, 307 bytes added, 567 bytes removed, diff: -260 (Tested on x86_64). It seems that pimlen arg could be left out as well and eq-sizedness of structs trapped with BUILD_BUG_ON but I don't think that's more than a cosmetic flaw since there aren't that many args anyway. Compile tested. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv4/ipmr.c')
-rw-r--r--net/ipv4/ipmr.c103
1 files changed, 39 insertions, 64 deletions
diff --git a/net/ipv4/ipmr.c b/net/ipv4/ipmr.c
index 244a624e0b18..14666449dc1c 100644
--- a/net/ipv4/ipmr.c
+++ b/net/ipv4/ipmr.c
@@ -1482,29 +1482,13 @@ dont_forward:
return 0;
}
-#ifdef CONFIG_IP_PIMSM_V1
-/*
- * Handle IGMP messages of PIMv1
- */
-
-int pim_rcv_v1(struct sk_buff * skb)
+#ifdef CONFIG_IP_PIMSM
+static int __pim_rcv(struct sk_buff *skb, unsigned int pimlen)
{
- struct igmphdr *pim;
- struct iphdr *encap;
- struct net_device *reg_dev = NULL;
-
- if (!pskb_may_pull(skb, sizeof(*pim) + sizeof(*encap)))
- goto drop;
+ struct net_device *reg_dev = NULL;
+ struct iphdr *encap;
- pim = igmp_hdr(skb);
-
- if (!mroute_do_pim ||
- skb->len < sizeof(*pim) + sizeof(*encap) ||
- pim->group != PIM_V1_VERSION || pim->code != PIM_V1_REGISTER)
- goto drop;
-
- encap = (struct iphdr *)(skb_transport_header(skb) +
- sizeof(struct igmphdr));
+ encap = (struct iphdr *)(skb_transport_header(skb) + pimlen);
/*
Check that:
a. packet is really destinted to a multicast group
@@ -1513,8 +1497,8 @@ int pim_rcv_v1(struct sk_buff * skb)
*/
if (!ipv4_is_multicast(encap->daddr) ||
encap->tot_len == 0 ||
- ntohs(encap->tot_len) + sizeof(*pim) > skb->len)
- goto drop;
+ ntohs(encap->tot_len) + pimlen > skb->len)
+ return 1;
read_lock(&mrt_lock);
if (reg_vif_num >= 0)
@@ -1524,7 +1508,7 @@ int pim_rcv_v1(struct sk_buff * skb)
read_unlock(&mrt_lock);
if (reg_dev == NULL)
- goto drop;
+ return 1;
skb->mac_header = skb->network_header;
skb_pull(skb, (u8*)encap - skb->data);
@@ -1540,9 +1524,33 @@ int pim_rcv_v1(struct sk_buff * skb)
nf_reset(skb);
netif_rx(skb);
dev_put(reg_dev);
+
return 0;
- drop:
- kfree_skb(skb);
+}
+#endif
+
+#ifdef CONFIG_IP_PIMSM_V1
+/*
+ * Handle IGMP messages of PIMv1
+ */
+
+int pim_rcv_v1(struct sk_buff * skb)
+{
+ struct igmphdr *pim;
+
+ if (!pskb_may_pull(skb, sizeof(*pim) + sizeof(struct iphdr)))
+ goto drop;
+
+ pim = igmp_hdr(skb);
+
+ if (!mroute_do_pim ||
+ pim->group != PIM_V1_VERSION || pim->code != PIM_V1_REGISTER)
+ goto drop;
+
+ if (__pim_rcv(skb, sizeof(*pim))) {
+drop:
+ kfree_skb(skb);
+ }
return 0;
}
#endif
@@ -1551,10 +1559,8 @@ int pim_rcv_v1(struct sk_buff * skb)
static int pim_rcv(struct sk_buff * skb)
{
struct pimreghdr *pim;
- struct iphdr *encap;
- struct net_device *reg_dev = NULL;
- if (!pskb_may_pull(skb, sizeof(*pim) + sizeof(*encap)))
+ if (!pskb_may_pull(skb, sizeof(*pim) + sizeof(struct iphdr)))
goto drop;
pim = (struct pimreghdr *)skb_transport_header(skb);
@@ -1564,41 +1570,10 @@ static int pim_rcv(struct sk_buff * skb)
csum_fold(skb_checksum(skb, 0, skb->len, 0))))
goto drop;
- /* check if the inner packet is destined to mcast group */
- encap = (struct iphdr *)(skb_transport_header(skb) +
- sizeof(struct pimreghdr));
- if (!ipv4_is_multicast(encap->daddr) ||
- encap->tot_len == 0 ||
- ntohs(encap->tot_len) + sizeof(*pim) > skb->len)
- goto drop;
-
- read_lock(&mrt_lock);
- if (reg_vif_num >= 0)
- reg_dev = vif_table[reg_vif_num].dev;
- if (reg_dev)
- dev_hold(reg_dev);
- read_unlock(&mrt_lock);
-
- if (reg_dev == NULL)
- goto drop;
-
- skb->mac_header = skb->network_header;
- skb_pull(skb, (u8*)encap - skb->data);
- skb_reset_network_header(skb);
- skb->dev = reg_dev;
- skb->protocol = htons(ETH_P_IP);
- skb->ip_summed = 0;
- skb->pkt_type = PACKET_HOST;
- dst_release(skb->dst);
- reg_dev->stats.rx_bytes += skb->len;
- reg_dev->stats.rx_packets++;
- skb->dst = NULL;
- nf_reset(skb);
- netif_rx(skb);
- dev_put(reg_dev);
- return 0;
- drop:
- kfree_skb(skb);
+ if (__pim_rcv(skb, sizeof(*pim))) {
+drop:
+ kfree_skb(skb);
+ }
return 0;
}
#endif