diff --git a/net/sctp/ipv6.c b/net/sctp/ipv6.c index 321f175055bf..3a571d6614f9 100644 --- a/net/sctp/ipv6.c +++ b/net/sctp/ipv6.c @@ -80,6 +80,9 @@ #include +static inline int sctp_v6_addr_match_len(union sctp_addr *s1, + union sctp_addr *s2); + /* Event handler for inet6 address addition/deletion events. * The sctp_local_addr_list needs to be protocted by a spin lock since * multiple notifiers (say IPv4 and IPv6) may be running at the same @@ -244,8 +247,14 @@ static struct dst_entry *sctp_v6_get_dst(struct sctp_association *asoc, union sctp_addr *daddr, union sctp_addr *saddr) { - struct dst_entry *dst; + struct dst_entry *dst = NULL; struct flowi6 fl6; + struct sctp_bind_addr *bp; + struct sctp_sockaddr_entry *laddr; + union sctp_addr *baddr = NULL; + __u8 matchlen = 0; + __u8 bmatchlen; + sctp_scope_t scope; memset(&fl6, 0, sizeof(fl6)); ipv6_addr_copy(&fl6.daddr, &daddr->v6.sin6_addr); @@ -261,6 +270,39 @@ static struct dst_entry *sctp_v6_get_dst(struct sctp_association *asoc, } dst = ip6_route_output(&init_net, NULL, &fl6); + if (!asoc || saddr) + goto out; + + if (dst->error) { + dst_release(dst); + dst = NULL; + bp = &asoc->base.bind_addr; + scope = sctp_scope(daddr); + /* Walk through the bind address list and try to get a dst that + * matches a bind address as the source address. + */ + rcu_read_lock(); + list_for_each_entry_rcu(laddr, &bp->address_list, list) { + if (!laddr->valid) + continue; + if ((laddr->state == SCTP_ADDR_SRC) && + (laddr->a.sa.sa_family == AF_INET6) && + (scope <= sctp_scope(&laddr->a))) { + bmatchlen = sctp_v6_addr_match_len(daddr, + &laddr->a); + if (!baddr || (matchlen < bmatchlen)) { + baddr = &laddr->a; + matchlen = bmatchlen; + } + } + } + rcu_read_unlock(); + if (baddr) { + ipv6_addr_copy(&fl6.saddr, &baddr->v6.sin6_addr); + dst = ip6_route_output(&init_net, NULL, &fl6); + } + } +out: if (!dst->error) { struct rt6_info *rt; rt = (struct rt6_info *)dst;