net/icmpv6: Fix `icmpv6_neighbor` for link-local address

The netdev of link-local address cannot be auto decided, and the link-local address should always be reguarded as address on local network.

The problem we met:
When using `icmpv6_autoconfig` with multiple netdev, the `icmpv6_neighbor` may take out wrong netdev with ip address already set, then it may send solicitation with wrong address (`dev->d_ipv6draddr`) on wrong device, and regard the link-local address as conflict (because `dev->d_ipv6draddr` exists on this network).

Signed-off-by: Zhe Weng <wengzhe@xiaomi.com>

net/icmpv6/icmpv6.h

@@ -205,6 +205,8 @@ void icmpv6_input(FAR struct net_driver_s *dev, unsigned int iplen);
  *   ICMPv6 Neighbor Advertisement.
  *
  * Input Parameters:
+ *   dev      The suggested device driver structure to do the solicitation,
+ *            can be NULL for auto decision, must set for link-local ipaddr.
  *   ipaddr   The IPv6 address to be queried.
  *
  * Returned Value:
@@ -221,9 +223,10 @@ void icmpv6_input(FAR struct net_driver_s *dev, unsigned int iplen);
  ****************************************************************************/
 
 #ifdef CONFIG_NET_ICMPv6_NEIGHBOR
-int icmpv6_neighbor(const net_ipv6addr_t ipaddr);
+int icmpv6_neighbor(FAR struct net_driver_s *dev,
+                    const net_ipv6addr_t ipaddr);
 #else
-#  define icmpv6_neighbor(i) (0)
+#  define icmpv6_neighbor(d,i) (0)
 #endif
 
 /****************************************************************************

net/icmpv6/icmpv6_autoconfig.c

@@ -332,7 +332,7 @@ int icmpv6_autoconfig(FAR struct net_driver_s *dev)
    *    method must be employed.
    */
 
-  ret = icmpv6_neighbor(lladdr);
+  ret = icmpv6_neighbor(dev, lladdr);
   if (ret >= 0)
     {
       /* Hmmm... someone else responded to our Neighbor Solicitation.  We

net/icmpv6/icmpv6_neighbor.c

@@ -161,6 +161,8 @@ static uint16_t icmpv6_neighbor_eventhandler(FAR struct net_driver_s *dev,
  *   ICMPv6 Neighbor Advertisement.
  *
  * Input Parameters:
+ *   dev      The suggested device driver structure to do the solicitation,
+ *            can be NULL for auto decision, must set for link-local ipaddr.
  *   ipaddr   The IPv6 address to be queried.
  *
  * Returned Value:
@@ -176,9 +178,9 @@ static uint16_t icmpv6_neighbor_eventhandler(FAR struct net_driver_s *dev,
  *
  ****************************************************************************/
 
-int icmpv6_neighbor(const net_ipv6addr_t ipaddr)
+int icmpv6_neighbor(FAR struct net_driver_s *dev,
+                    const net_ipv6addr_t ipaddr)
 {
-  FAR struct net_driver_s *dev;
   struct icmpv6_notify_s notify;
   struct icmpv6_neighbor_s state;
   net_ipv6addr_t lookup;
@@ -202,7 +204,11 @@ int icmpv6_neighbor(const net_ipv6addr_t ipaddr)
 
   /* Get the device that can route this request */
 
-  dev = netdev_findby_ripv6addr(g_ipv6_unspecaddr, ipaddr);
+  if (!dev)
+    {
+      dev = netdev_findby_ripv6addr(g_ipv6_unspecaddr, ipaddr);
+    }
+
   if (!dev)
     {
       nerr("ERROR: Unreachable: %08lx\n", (unsigned long)ipaddr);
@@ -212,7 +218,8 @@ int icmpv6_neighbor(const net_ipv6addr_t ipaddr)
 
   /* Check if the destination address is on the local network. */
 
-  if (net_ipv6addr_maskcmp(ipaddr, dev->d_ipv6addr, dev->d_ipv6netmask))
+  if (net_ipv6addr_maskcmp(ipaddr, dev->d_ipv6addr, dev->d_ipv6netmask) ||
+      net_is_addr_linklocal(ipaddr))
     {
       /* Yes.. use the input address for the lookup */
 

net/icmpv6/icmpv6_sendmsg.c

@@ -338,7 +338,7 @@ ssize_t icmpv6_sendmsg(FAR struct socket *psock, FAR struct msghdr *msg,
 #ifdef CONFIG_NET_ICMPv6_NEIGHBOR
   /* Make sure that the IP address mapping is in the Neighbor Table */
 
-  ret = icmpv6_neighbor(inaddr->sin6_addr.s6_addr16);
+  ret = icmpv6_neighbor(dev, inaddr->sin6_addr.s6_addr16);
   if (ret < 0)
     {
       nerr("ERROR: Not reachable\n");

net/sixlowpan/sixlowpan_tcpsend.c

@@ -774,7 +774,7 @@ ssize_t psock_6lowpan_tcp_send(FAR struct socket *psock, FAR const void *buf,
 #ifdef CONFIG_NET_ICMPv6_NEIGHBOR
   /* Make sure that the IP address mapping is in the Neighbor Table */
 
-  ret = icmpv6_neighbor(conn->u.ipv6.raddr);
+  ret = icmpv6_neighbor(dev, conn->u.ipv6.raddr);
   if (ret < 0)
     {
       nerr("ERROR: Not reachable\n");

net/sixlowpan/sixlowpan_udpsend.c

@@ -213,7 +213,7 @@ ssize_t psock_6lowpan_udp_sendto(FAR struct socket *psock,
 #ifdef CONFIG_NET_ICMPv6_NEIGHBOR
   /* Make sure that the IP address mapping is in the Neighbor Table */
 
-  ret = icmpv6_neighbor(to6->sin6_addr.in6_u.u6_addr16);
+  ret = icmpv6_neighbor(dev, to6->sin6_addr.in6_u.u6_addr16);
   if (ret < 0)
     {
       nerr("ERROR: Not reachable\n");

net/tcp/tcp_conn.c

@@ -1494,7 +1494,7 @@ int tcp_connect(FAR struct tcp_conn_s *conn, FAR const struct sockaddr *addr)
     {
       /* Make sure that the IP address mapping is in the Neighbor Table */
 
-      ret = icmpv6_neighbor(conn->u.ipv6.raddr);
+      ret = icmpv6_neighbor(NULL, conn->u.ipv6.raddr);
     }
 #endif /* CONFIG_NET_ICMPv6_NEIGHBOR */
 

net/tcp/tcp_send_buffered.c

@@ -1299,7 +1299,7 @@ ssize_t psock_tcp_send(FAR struct socket *psock, FAR const void *buf,
     {
       /* Make sure that the IP address mapping is in the Neighbor Table */
 
-      ret = icmpv6_neighbor(conn->u.ipv6.raddr);
+      ret = icmpv6_neighbor(NULL, conn->u.ipv6.raddr);
     }
 #endif /* CONFIG_NET_ICMPv6_NEIGHBOR */
 

net/tcp/tcp_send_unbuffered.c

@@ -525,7 +525,7 @@ ssize_t psock_tcp_send(FAR struct socket *psock,
     {
       /* Make sure that the IP address mapping is in the Neighbor Table */
 
-      ret = icmpv6_neighbor(conn->u.ipv6.raddr);
+      ret = icmpv6_neighbor(NULL, conn->u.ipv6.raddr);
     }
 #endif /* CONFIG_NET_ICMPv6_NEIGHBOR */
 

net/tcp/tcp_sendfile.c

@@ -450,7 +450,7 @@ ssize_t tcp_sendfile(FAR struct socket *psock, FAR struct file *infile,
     {
       /* Make sure that the IP address mapping is in the Neighbor Table */
 
-      ret = icmpv6_neighbor(conn->u.ipv6.raddr);
+      ret = icmpv6_neighbor(NULL, conn->u.ipv6.raddr);
     }
 #endif /* CONFIG_NET_ICMPv6_NEIGHBOR */
 

net/udp/udp_sendto_buffered.c

@@ -651,7 +651,7 @@ ssize_t psock_udp_sendto(FAR struct socket *psock, FAR const void *buf,
 
       /* Make sure that the IP address mapping is in the Neighbor Table */
 
-      ret = icmpv6_neighbor(destipaddr);
+      ret = icmpv6_neighbor(NULL, destipaddr);
     }
 #endif /* CONFIG_NET_ICMPv6_NEIGHBOR */
 

net/udp/udp_sendto_unbuffered.c

@@ -382,7 +382,7 @@ ssize_t psock_udp_sendto(FAR struct socket *psock, FAR const void *buf,
 
       /* Make sure that the IP address mapping is in the Neighbor Table */
 
-      ret = icmpv6_neighbor(destipaddr);
+      ret = icmpv6_neighbor(NULL, destipaddr);
     }
 #endif /* CONFIG_NET_ICMPv6_NEIGHBOR */