net/ipv6: Refactor fib6_rule_action

Move source address lookup from fib6_rule_action to a helper. It will be
used in a later patch by a second variant for fib6_rule_action.

Signed-off-by: David Ahern <dsahern@gmail.com>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

diff --git a/net/ipv6/fib6_rules.c b/net/ipv6/fib6_rules.c
index 6547fc6491a63af0ccbab6fd4ca04c8c64c8622b..d040c4bff3a096a5e78dfaf2488c34cd3159e891 100644 (file)
--- a/net/ipv6/fib6_rules.c
+++ b/net/ipv6/fib6_rules.c
@@ -96,6 +96,31 @@ struct dst_entry *fib6_rule_lookup(struct net *net, struct flowi6 *fl6,
        return &net->ipv6.ip6_null_entry->dst;
 }
 
+static int fib6_rule_saddr(struct net *net, struct fib_rule *rule, int flags,
+                          struct flowi6 *flp6, const struct net_device *dev)
+{
+       struct fib6_rule *r = (struct fib6_rule *)rule;
+
+       /* If we need to find a source address for this traffic,
+        * we check the result if it meets requirement of the rule.
+        */
+       if ((rule->flags & FIB_RULE_FIND_SADDR) &&
+           r->src.plen && !(flags & RT6_LOOKUP_F_HAS_SADDR)) {
+               struct in6_addr saddr;
+
+               if (ipv6_dev_get_saddr(net, dev, &flp6->daddr,
+                                      rt6_flags2srcprefs(flags), &saddr))
+                       return -EAGAIN;
+
+               if (!ipv6_prefix_equal(&saddr, &r->src.addr, r->src.plen))
+                       return -EAGAIN;
+
+               flp6->saddr = saddr;
+       }
+
+       return 0;
+}
+
 static int fib6_rule_action(struct fib_rule *rule, struct flowi *flp,
                            int flags, struct fib_lookup_arg *arg)
 {
@@ -134,27 +159,12 @@ static int fib6_rule_action(struct fib_rule *rule, struct flowi *flp,
 
        rt = lookup(net, table, flp6, arg->lookup_data, flags);
        if (rt != net->ipv6.ip6_null_entry) {
-               struct fib6_rule *r = (struct fib6_rule *)rule;
-
-               /*
-                * If we need to find a source address for this traffic,
-                * we check the result if it meets requirement of the rule.
-                */
-               if ((rule->flags & FIB_RULE_FIND_SADDR) &&
-                   r->src.plen && !(flags & RT6_LOOKUP_F_HAS_SADDR)) {
-                       struct in6_addr saddr;
-
-                       if (ipv6_dev_get_saddr(net,
-                                              ip6_dst_idev(&rt->dst)->dev,
-                                              &flp6->daddr,
-                                              rt6_flags2srcprefs(flags),
-                                              &saddr))
-                               goto again;
-                       if (!ipv6_prefix_equal(&saddr, &r->src.addr,
-                                              r->src.plen))
-                               goto again;
-                       flp6->saddr = saddr;
-               }
+               err = fib6_rule_saddr(net, rule, flags, flp6,
+                                     ip6_dst_idev(&rt->dst)->dev);
+
+               if (err == -EAGAIN)
+                       goto again;
+
                err = rt->dst.error;
                if (err != -EAGAIN)
                        goto out;