BSD: Use MSG_DONTROUTE for unicast packets on FreeBSD

BSD systems cannot use SO_DONTROUTE, because it does not work properly
with multicast packets (perhaps it tries to find iface based on multicast
group address). But we can use MSG_DONTROUTE sendmsg() flag for unicast
packets. Works on FreeBSD, is ignored on OpenBSD and is broken on NetBSD
(i guess due to integrated routing table and ARP table).

1 files changed, 3 insertions, 0 deletions

diff --git a/lib/ip.h b/lib/ip.h
index 298b72a7..d876a707 100644
--- a/lib/ip.h
+++ b/lib/ip.h
@@ -309,6 +309,9 @@ static inline int ip6_is_v4mapped(ip6_addr a)
 #define ipa_is_link_local(x) 0
 #endif
 
+static inline int ip4_is_unicast(ip4_addr a)
+{ return _I(a) < 0xe0000000; }
+
 static inline int ipa_classify_net(ip_addr a)
 { return ipa_zero2(a) ? (IADDR_HOST | SCOPE_UNIVERSE) : ipa_classify(a); }