isisd: implement draft-ietf-isis-ext-eth and support p2p over LAN on BSD

Signed-off-by: Christian Franke <chris@opensourcerouting.org>

isisd/isis_bpf.c

@@ -212,16 +212,11 @@ isis_sock_init (struct isis_circuit *circuit)
       goto end;
     }
 
-  if (circuit->circ_type == CIRCUIT_T_BROADCAST)
+  if (if_is_broadcast(circuit->interface))
     {
       circuit->tx = isis_send_pdu_bcast;
       circuit->rx = isis_recv_pdu_bcast;
     }
-  else if (circuit->circ_type == CIRCUIT_T_P2P)
-    {
-      circuit->tx = isis_send_pdu_p2p;
-      circuit->rx = isis_recv_pdu_p2p;
-    }
   else
     {
       zlog_warn ("isis_sock_init(): unknown circuit type");
@@ -283,23 +278,6 @@ isis_recv_pdu_bcast (struct isis_circuit *circuit, u_char * ssnpa)
   return ISIS_OK;
 }
 
-int
-isis_recv_pdu_p2p (struct isis_circuit *circuit, u_char * ssnpa)
-{
-  int bytesread;
-
-  bytesread = stream_read (circuit->rcv_stream, circuit->fd, 
-                           circuit->interface->mtu);
-
-  if (bytesread < 0)
-    {
-      zlog_warn ("isis_recv_pdu_p2p(): read () failed: %s", safe_strerror (errno));
-      return ISIS_WARNING;
-    }
-
-  return ISIS_OK;
-}
-
 int
 isis_send_pdu_bcast (struct isis_circuit *circuit, int level)
 {
@@ -327,7 +305,8 @@ isis_send_pdu_bcast (struct isis_circuit *circuit, int level)
   else
     memcpy (eth->ether_dhost, ALL_L2_ISS, ETHER_ADDR_LEN);
   memcpy (eth->ether_shost, circuit->u.bc.snpa, ETHER_ADDR_LEN);
-  eth->ether_type = htons (stream_get_endp (circuit->snd_stream) + LLC_LEN);
+  size_t frame_size = stream_get_endp(circuit->snd_stream) + LLC_LEN;
+  eth->ether_type = htons(isis_ethertype(frame_size));
 
   /*
    * Then the LLC
@@ -354,10 +333,4 @@ isis_send_pdu_bcast (struct isis_circuit *circuit, int level)
   return ISIS_OK;
 }
 
-int
-isis_send_pdu_p2p (struct isis_circuit *circuit, int level)
-{
-  return ISIS_OK;
-}
-
 #endif /* ISIS_METHOD == ISIS_METHOD_BPF */

isisd/isis_constants.h

@@ -171,4 +171,14 @@
 #define ETH_ALEN 6
 #endif
 
+#define MAX_LLC_LEN 0x5ff
+#define ETHERTYPE_EXT_LLC 0x8870
+
+static inline uint16_t isis_ethertype(size_t len)
+{
+  if (len > MAX_LLC_LEN)
+    return ETHERTYPE_EXT_LLC;
+  return len;
+}
+
 #endif /* ISIS_CONSTANTS_H */

isisd/isis_pfpacket.c

@@ -371,7 +371,9 @@ isis_send_pdu_bcast (struct isis_circuit *circuit, int level)
   stream_set_getp (circuit->snd_stream, 0);
   memset (&sa, 0, sizeof (struct sockaddr_ll));
   sa.sll_family = AF_PACKET;
-  sa.sll_protocol = htons (stream_get_endp (circuit->snd_stream) + LLC_LEN);
+
+  size_t frame_size = stream_get_endp(circuit->snd_stream) + LLC_LEN;
+  sa.sll_protocol = htons(isis_ethertype(frame_size));
   sa.sll_ifindex = circuit->interface->ifindex;
   sa.sll_halen = ETH_ALEN;
   /* RFC5309 section 4.1 recommends ALL_ISS */
@@ -418,7 +420,6 @@ isis_send_pdu_p2p (struct isis_circuit *circuit, int level)
   stream_set_getp (circuit->snd_stream, 0);
   memset (&sa, 0, sizeof (struct sockaddr_ll));
   sa.sll_family = AF_PACKET;
-  sa.sll_protocol = htons (stream_get_endp (circuit->snd_stream) + LLC_LEN);
   sa.sll_ifindex = circuit->interface->ifindex;
   sa.sll_halen = ETH_ALEN;
   if (level == 1)