Check for link-local addresses in a specific function.

message.c

@@ -57,8 +57,6 @@ struct timeval unicast_flush_timeout = {0, 0};
 
 static const unsigned char v4prefix[16] =
     {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0xFF, 0xFF, 0, 0, 0, 0 };
-static const unsigned char ll_prefix[16] =
-    {0xFE, 0x80};
 
 static int
 network_prefix(int ae, int plen, unsigned int omitted,
@@ -135,7 +133,7 @@ parse_packet(const unsigned char *from, struct network *net,
     unsigned char router_id[8], v4_prefix[16], v6_prefix[16],
         v4_nh[16], v6_nh[16];
 
-    if(!in_prefix(from, ll_prefix, 64)) {
+    if(!linklocal(from)) {
         fprintf(stderr, "Received packet from non-local address %s.\n",
                 format_address(from));
         return;
@@ -1127,7 +1125,7 @@ send_ihu(struct neighbour *neigh, struct network *net)
            neigh->network->ifname,
            format_address(neigh->address));
 
-    ll = in_prefix(neigh->address, ll_prefix, 64);
+    ll = linklocal(neigh->address);
 
     if(unicast_neighbour != neigh) {
         start_message(net, MESSAGE_IHU, ll ? 14 : 22);

util.c

@@ -220,6 +220,9 @@ mask_prefix(unsigned char *restrict ret,
 static const unsigned char v4prefix[16] =
     {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0xFF, 0xFF, 0, 0, 0, 0 };
 
+static const unsigned char llprefix[16] =
+    {0xFE, 0x80};
+
 const char *
 format_address(const unsigned char *address)
 {
@@ -406,6 +409,12 @@ martian_prefix(const unsigned char *prefix, int plen)
           (plen >= 100 && (prefix[12] & 0xE0) == 0xE0)));
 }
 
+int
+linklocal(const unsigned char *address)
+{
+    return memcmp(address, llprefix, 8) == 0;
+}
+
 int
 v4mapped(const unsigned char *address)
 {

util.h

@@ -95,6 +95,7 @@ int parse_net(const char *net, unsigned char *prefix_r, unsigned char *plen_r,
 int parse_eui64(const char *eui, unsigned char *eui_r);
 int wait_for_fd(int direction, int fd, int msecs);
 int martian_prefix(const unsigned char *prefix, int plen) ATTRIBUTE ((pure));
+int linklocal(const unsigned char *address) ATTRIBUTE ((pure));
 int v4mapped(const unsigned char *address) ATTRIBUTE ((pure));
 void v4tov6(unsigned char *dst, const unsigned char *src);
 int daemonise(void);