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Diffstat (limited to 'net/ipv4/route.c')
-rw-r--r--net/ipv4/route.c81
1 files changed, 62 insertions, 19 deletions
diff --git a/net/ipv4/route.c b/net/ipv4/route.c
index 76ca4e75f785..85f184e429c6 100644
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c
@@ -1152,7 +1152,7 @@ static void ipv4_link_failure(struct sk_buff *skb)
dst_set_expires(&rt->dst, 0);
}
-static int ip_rt_bug(struct sock *sk, struct sk_buff *skb)
+static int ip_rt_bug(struct net *net, struct sock *sk, struct sk_buff *skb)
{
pr_debug("%s: %pI4 -> %pI4, %s\n",
__func__, &ip_hdr(skb)->saddr, &ip_hdr(skb)->daddr,
@@ -1651,6 +1651,48 @@ out:
return err;
}
+#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.
+ */
+static int ip_multipath_icmp_hash(struct sk_buff *skb)
+{
+ const struct iphdr *outer_iph = ip_hdr(skb);
+ struct icmphdr _icmph;
+ const struct icmphdr *icmph;
+ struct iphdr _inner_iph;
+ const struct iphdr *inner_iph;
+
+ if (unlikely((outer_iph->frag_off & htons(IP_OFFSET)) != 0))
+ goto standard_hash;
+
+ icmph = skb_header_pointer(skb, outer_iph->ihl * 4, sizeof(_icmph),
+ &_icmph);
+ if (!icmph)
+ goto standard_hash;
+
+ if (icmph->type != ICMP_DEST_UNREACH &&
+ icmph->type != ICMP_REDIRECT &&
+ icmph->type != ICMP_TIME_EXCEEDED &&
+ icmph->type != ICMP_PARAMETERPROB) {
+ goto standard_hash;
+ }
+
+ inner_iph = skb_header_pointer(skb,
+ outer_iph->ihl * 4 + sizeof(_icmph),
+ sizeof(_inner_iph), &_inner_iph);
+ if (!inner_iph)
+ goto standard_hash;
+
+ return fib_multipath_hash(inner_iph->daddr, inner_iph->saddr);
+
+standard_hash:
+ return fib_multipath_hash(outer_iph->saddr, outer_iph->daddr);
+}
+
+#endif /* CONFIG_IP_ROUTE_MULTIPATH */
+
static int ip_mkroute_input(struct sk_buff *skb,
struct fib_result *res,
const struct flowi4 *fl4,
@@ -1658,8 +1700,15 @@ static int ip_mkroute_input(struct sk_buff *skb,
__be32 daddr, __be32 saddr, u32 tos)
{
#ifdef CONFIG_IP_ROUTE_MULTIPATH
- if (res->fi && res->fi->fib_nhs > 1)
- fib_select_multipath(res);
+ if (res->fi && res->fi->fib_nhs > 1) {
+ int h;
+
+ 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
/* create a routing cache entry */
@@ -2026,7 +2075,8 @@ add:
* Major route resolver routine.
*/
-struct rtable *__ip_route_output_key(struct net *net, struct flowi4 *fl4)
+struct rtable *__ip_route_output_key_hash(struct net *net, struct flowi4 *fl4,
+ int mp_hash)
{
struct net_device *dev_out = NULL;
__u8 tos = RT_FL_TOS(fl4);
@@ -2146,7 +2196,8 @@ struct rtable *__ip_route_output_key(struct net *net, struct flowi4 *fl4)
if (err) {
res.fi = NULL;
res.table = NULL;
- if (fl4->flowi4_oif) {
+ if (fl4->flowi4_oif &&
+ !netif_index_is_l3_master(net, fl4->flowi4_oif)) {
/* Apparently, routing tables are wrong. Assume,
that the destination is on link.
@@ -2188,18 +2239,7 @@ struct rtable *__ip_route_output_key(struct net *net, struct flowi4 *fl4)
goto make_route;
}
-#ifdef CONFIG_IP_ROUTE_MULTIPATH
- if (res.fi->fib_nhs > 1 && fl4->flowi4_oif == 0)
- fib_select_multipath(&res);
- else
-#endif
- if (!res.prefixlen &&
- res.table->tb_num_default > 1 &&
- res.type == RTN_UNICAST && !fl4->flowi4_oif)
- fib_select_default(fl4, &res);
-
- if (!fl4->saddr)
- fl4->saddr = FIB_RES_PREFSRC(net, res);
+ fib_select_path(net, &res, fl4, mp_hash);
dev_out = FIB_RES_DEV(res);
fl4->flowi4_oif = dev_out->ifindex;
@@ -2212,7 +2252,7 @@ out:
rcu_read_unlock();
return rth;
}
-EXPORT_SYMBOL_GPL(__ip_route_output_key);
+EXPORT_SYMBOL_GPL(__ip_route_output_key_hash);
static struct dst_entry *ipv4_blackhole_dst_check(struct dst_entry *dst, u32 cookie)
{
@@ -2264,7 +2304,7 @@ struct dst_entry *ipv4_blackhole_route(struct net *net, struct dst_entry *dst_or
new->__use = 1;
new->input = dst_discard;
- new->output = dst_discard_sk;
+ new->output = dst_discard_out;
new->dev = ort->dst.dev;
if (new->dev)
@@ -2468,6 +2508,9 @@ static int inet_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh)
fl4.flowi4_oif = tb[RTA_OIF] ? nla_get_u32(tb[RTA_OIF]) : 0;
fl4.flowi4_mark = mark;
+ if (netif_index_is_l3_master(net, fl4.flowi4_oif))
+ fl4.flowi4_flags = FLOWI_FLAG_L3MDEV_SRC | FLOWI_FLAG_SKIP_NH_OIF;
+
if (iif) {
struct net_device *dev;