Skip to contentSkip to conversation

bonding: Doesn't support IPv6

PATCH In review John 3 participants 4 messages Oct 29, 2011

Subsystems (3)
Networking Network drivers Bonding driver
lore
Share & tools
lore

John

author
#0 lore raw

PATCH 1/2 bonding: Doesn't support IPv6

drivers/net/bonding/bond_main.c +41 -12
@@ -3533,14 +3533,26 @@
 static int bond_xmit_hash_policy_l23(struct sk_buff *skb, int count)
 {
 	struct ethhdr *data = (struct ethhdr *)skb->data;
-	struct iphdr *iph = ip_hdr(skb);
 
-	if (skb->protocol == htons(ETH_P_IP)) {
+	if (skb->protocol == htons(ETH_P_IP) &&
+		skb_network_header_len(skb) >= sizeof(struct iphdr)) {
+		struct iphdr *iph = ip_hdr(skb);
 		return ((ntohl(iph->saddr ^ iph->daddr) & 0xffff) ^
 			(data->h_dest[5] ^ data->h_source[5])) % count;
+	} else if (skb->protocol == htons(ETH_P_IPV6) &&
+		skb_network_header_len(skb) >= sizeof(struct ipv6hdr)) {
+		struct ipv6hdr *ipv6h = ipv6_hdr(skb);
+		u32 v6hash =
+			(ipv6h->saddr.s6_addr32[1] ^ ipv6h->daddr.s6_addr32[1]) ^
+			(ipv6h->saddr.s6_addr32[2] ^ ipv6h->daddr.s6_addr32[2]) ^
+			(ipv6h->saddr.s6_addr32[3] ^ ipv6h->daddr.s6_addr32[3]);
+		v6hash = (v6hash >> 16) ^ (v6hash >> 8) ^ v6hash;
+		return (v6hash ^ data->h_dest[5] ^ data->h_source[5]) % count;
 	}
 
-	return (data->h_dest[5] ^ data->h_source[5]) % count;
+	if (skb_headlen(skb) >= 6)
+		return (data->h_dest[5] ^ data->h_source[5]) % count;
+	return 0;
 }
 
 /*

@@ -3551,22 +3563,39 @@
 static int bond_xmit_hash_policy_l34(struct sk_buff *skb, int count)
 {
 	struct ethhdr *data = (struct ethhdr *)skb->data;
-	struct iphdr *iph = ip_hdr(skb);
-	__be16 *layer4hdr = (__be16 *)((u32 *)iph + iph->ihl);
-	int layer4_xor = 0;
+	u32 layer4_xor = 0;
 
 	if (skb->protocol == htons(ETH_P_IP)) {
+		struct iphdr *iph = ip_hdr(skb);
+		__be16 *layer4hdr = (__be16 *)((u32 *)iph + iph->ihl);
+		if (iph->ihl * sizeof(u32) + sizeof(__be16) * 2 >
+			skb_headlen(skb) - skb_network_offset(skb)) goto SHORT_HEADER;
 		if (!(iph->frag_off & htons(IP_MF|IP_OFFSET)) &&
-		    (iph->protocol == IPPROTO_TCP ||
-		     iph->protocol == IPPROTO_UDP)) {
+			(iph->protocol == IPPROTO_TCP ||
+			iph->protocol == IPPROTO_UDP)) {
 			layer4_xor = ntohs((*layer4hdr ^ *(layer4hdr + 1)));
 		}
 		return (layer4_xor ^
 			((ntohl(iph->saddr ^ iph->daddr)) & 0xffff)) % count;
-
-	}
-
-	return (data->h_dest[5] ^ data->h_source[5]) % count;
+	} else if (skb->protocol == htons(ETH_P_IPV6)) {
+		struct ipv6hdr *ipv6h = ipv6_hdr(skb);
+		__be16 *layer4hdrv6 = (__be16 *)((u8 *)ipv6h + sizeof(*ipv6h));
+		if (sizeof(struct ipv6hdr) + sizeof(__be16) * 2 >
+			skb_headlen(skb) - skb_network_offset(skb)) goto SHORT_HEADER;
+		if (ipv6h->nexthdr == IPPROTO_TCP || ipv6h->nexthdr == IPPROTO_UDP) {
+			layer4_xor = (*layer4hdrv6 ^ *(layer4hdrv6 + 1));
+		}
+		layer4_xor ^=
+			(ipv6h->saddr.s6_addr32[1] ^ ipv6h->daddr.s6_addr32[1]) ^
+			(ipv6h->saddr.s6_addr32[2] ^ ipv6h->daddr.s6_addr32[2]) ^
+			(ipv6h->saddr.s6_addr32[3] ^ ipv6h->daddr.s6_addr32[3]);
+		return ((layer4_xor >> 16) ^ (layer4_xor >> 8) ^ layer4_xor) % count;
+	}
+
+	SHORT_HEADER:
+	if (skb_headlen(skb) >= 6)
+		return (data->h_dest[5] ^ data->h_source[5]) % count;
+	return 0;
 }
 
 /*
#1 lore raw

2011/10/29 John <[email protected]>:

Quoted 2 lines
drivers/net/bonding/bond_main.c   2011-10-27 11:26:20.000000000 -0700 renamed from drivers/net/bonding/bond_main.c   2011-04-19 11:18:48.000000000 -0700 +0 -0

[...]

Quoted 1 line

+               v6hash = (v6hash >> 16) ^ (v6hash >> 8) ^ v6hash;

This XORs in only 3 of 4 bytes, and assuming count > 256 (its unlikely you have more than 256 slaves in bond) the most significant byte is wasted. It should be:

v6hash ^= v6hash >> 16;
v6hash ^= v6hash >> 8;

Same for IPv4 part.

OTOH, if that was your intention, then the description in your mail was wrong.

Best Regards,
Michał Mirosław

#2 lore raw
Quoted 10 lines · Michał Mirosław

2011/10/29 John <[email protected]>:

Quoted 2 lines
drivers/net/bonding/bond_main.c 2011-10-27 11:26:20.000000000 -0700 renamed from drivers/net/bonding/bond_main.c 2011-04-19 11:18:48.000000000 -0700 +0 -0

[...]

Quoted 1 line

+ v6hash = (v6hash >> 16) ^ (v6hash >> 8) ^ v6hash;

This XORs in only 3 of 4 bytes, and assuming count > 256 (its unlikely you have more than 256 slaves in bond) the most significant byte is wasted. It should be:

Quoted 7 lines

v6hash ^= v6hash >> 16;
v6hash ^= v6hash >> 8;

Same for IPv4 part.

OTOH, if that was your intention, then the description in your mail was wrong.

Same end result :)

#3 lore raw
Quoted 14 lines · Eric Dumazet
Quoted 13 lines · Michał Mirosław

2011/10/29 John <[email protected]>:

Quoted 2 lines
drivers/net/bonding/bond_main.c 2011-10-27 11:26:20.000000000 -0700 renamed from drivers/net/bonding/bond_main.c 2011-04-19 11:18:48.000000000 -0700 +0 -0

[...]

Quoted 1 line

+ v6hash = (v6hash >> 16) ^ (v6hash >> 8) ^ v6hash;

This XORs in only 3 of 4 bytes, and assuming count > 256 (its unlikely you have more than 256 slaves in bond) the most significant byte is wasted. It should be:

v6hash ^= v6hash >> 16;
v6hash ^= v6hash >> 8;

Quoted 7 lines
Quoted 4 lines

Same for IPv4 part.

OTOH, if that was your intention, then the description in your mail was wrong.

Same end result :)

Oh well, not exactly, there was a reason for using two different C instructions ;)

ALso the modulo is expensive...