diff options
Diffstat (limited to 'net/ipv4/route.c')
| -rw-r--r-- | net/ipv4/route.c | 92 |
1 files changed, 70 insertions, 22 deletions
diff --git a/net/ipv4/route.c b/net/ipv4/route.c index 8471dd116771..5dda1ef81c7e 100644 --- a/net/ipv4/route.c +++ b/net/ipv4/route.c @@ -1734,45 +1734,97 @@ out: } #ifdef CONFIG_IP_ROUTE_MULTIPATH - /* To make ICMP packets follow the right flow, the multipath hash is - * calculated from the inner IP addresses in reverse order. + * calculated from the inner IP addresses. */ -static int ip_multipath_icmp_hash(struct sk_buff *skb) +static void ip_multipath_l3_keys(const struct sk_buff *skb, + struct flow_keys *hash_keys) { const struct iphdr *outer_iph = ip_hdr(skb); - struct icmphdr _icmph; + const struct iphdr *inner_iph; const struct icmphdr *icmph; struct iphdr _inner_iph; - const struct iphdr *inner_iph; + struct icmphdr _icmph; + + hash_keys->addrs.v4addrs.src = outer_iph->saddr; + hash_keys->addrs.v4addrs.dst = outer_iph->daddr; + if (likely(outer_iph->protocol != IPPROTO_ICMP)) + return; if (unlikely((outer_iph->frag_off & htons(IP_OFFSET)) != 0)) - goto standard_hash; + return; icmph = skb_header_pointer(skb, outer_iph->ihl * 4, sizeof(_icmph), &_icmph); if (!icmph) - goto standard_hash; + return; if (icmph->type != ICMP_DEST_UNREACH && icmph->type != ICMP_REDIRECT && icmph->type != ICMP_TIME_EXCEEDED && - icmph->type != ICMP_PARAMETERPROB) { - goto standard_hash; - } + icmph->type != ICMP_PARAMETERPROB) + return; inner_iph = skb_header_pointer(skb, outer_iph->ihl * 4 + sizeof(_icmph), sizeof(_inner_iph), &_inner_iph); if (!inner_iph) - goto standard_hash; + return; + hash_keys->addrs.v4addrs.src = inner_iph->saddr; + hash_keys->addrs.v4addrs.dst = inner_iph->daddr; +} - return fib_multipath_hash(inner_iph->daddr, inner_iph->saddr); +/* if skb is set it will be used and fl4 can be NULL */ +int fib_multipath_hash(const struct fib_info *fi, const struct flowi4 *fl4, + const struct sk_buff *skb) +{ + struct net *net = fi->fib_net; + struct flow_keys hash_keys; + u32 mhash; -standard_hash: - return fib_multipath_hash(outer_iph->saddr, outer_iph->daddr); -} + switch (net->ipv4.sysctl_fib_multipath_hash_policy) { + case 0: + memset(&hash_keys, 0, sizeof(hash_keys)); + hash_keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS; + if (skb) { + ip_multipath_l3_keys(skb, &hash_keys); + } else { + hash_keys.addrs.v4addrs.src = fl4->saddr; + hash_keys.addrs.v4addrs.dst = fl4->daddr; + } + break; + case 1: + /* skb is currently provided only when forwarding */ + if (skb) { + unsigned int flag = FLOW_DISSECTOR_F_STOP_AT_ENCAP; + struct flow_keys keys; + + /* short-circuit if we already have L4 hash present */ + if (skb->l4_hash) + return skb_get_hash_raw(skb) >> 1; + memset(&hash_keys, 0, sizeof(hash_keys)); + skb_flow_dissect_flow_keys(skb, &keys, flag); + hash_keys.addrs.v4addrs.src = keys.addrs.v4addrs.src; + hash_keys.addrs.v4addrs.dst = keys.addrs.v4addrs.dst; + hash_keys.ports.src = keys.ports.src; + hash_keys.ports.dst = keys.ports.dst; + hash_keys.basic.ip_proto = keys.basic.ip_proto; + } else { + memset(&hash_keys, 0, sizeof(hash_keys)); + hash_keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS; + hash_keys.addrs.v4addrs.src = fl4->saddr; + hash_keys.addrs.v4addrs.dst = fl4->daddr; + hash_keys.ports.src = fl4->fl4_sport; + hash_keys.ports.dst = fl4->fl4_dport; + hash_keys.basic.ip_proto = fl4->flowi4_proto; + } + break; + } + mhash = flow_hash_from_keys(&hash_keys); + return mhash >> 1; +} +EXPORT_SYMBOL_GPL(fib_multipath_hash); #endif /* CONFIG_IP_ROUTE_MULTIPATH */ static int ip_mkroute_input(struct sk_buff *skb, @@ -1782,12 +1834,8 @@ static int ip_mkroute_input(struct sk_buff *skb, { #ifdef CONFIG_IP_ROUTE_MULTIPATH if (res->fi && res->fi->fib_nhs > 1) { - int h; + int h = fib_multipath_hash(res->fi, NULL, skb); - if (unlikely(ip_hdr(skb)->protocol == IPPROTO_ICMP)) - h = ip_multipath_icmp_hash(skb); - else - h = fib_multipath_hash(saddr, daddr); fib_select_multipath(res, h); } #endif @@ -2203,7 +2251,7 @@ add: */ struct rtable *__ip_route_output_key_hash(struct net *net, struct flowi4 *fl4, - int mp_hash) + const struct sk_buff *skb) { struct net_device *dev_out = NULL; __u8 tos = RT_FL_TOS(fl4); @@ -2365,7 +2413,7 @@ struct rtable *__ip_route_output_key_hash(struct net *net, struct flowi4 *fl4, goto make_route; } - fib_select_path(net, &res, fl4, mp_hash); + fib_select_path(net, &res, fl4, skb); dev_out = FIB_RES_DEV(res); fl4->flowi4_oif = dev_out->ifindex; |