IP directed broadcast
[vpp.git] / src / vnet / ip / ip4_forward.c
index 6d5f07b..000710e 100644 (file)
@@ -39,6 +39,7 @@
 
 #include <vnet/vnet.h>
 #include <vnet/ip/ip.h>
+#include <vnet/ip/ip_frag.h>
 #include <vnet/ethernet/ethernet.h>    /* for ethernet_header_t */
 #include <vnet/ethernet/arp_packet.h>  /* for ethernet_arp_header_t */
 #include <vnet/ppp/ppp.h>
@@ -113,14 +114,14 @@ VLIB_REGISTER_NODE (ip4_lookup_node) =
 
 VLIB_NODE_FUNCTION_MULTIARCH (ip4_lookup_node, ip4_lookup);
 
-always_inline uword
+static uword
 ip4_load_balance (vlib_main_t * vm,
                  vlib_node_runtime_t * node, vlib_frame_t * frame)
 {
   vlib_combined_counter_main_t *cm = &load_balance_main.lbm_via_counters;
   u32 n_left_from, n_left_to_next, *from, *to_next;
   ip_lookup_next_t next;
-  u32 thread_index = vlib_get_thread_index ();
+  u32 thread_index = vm->thread_index;
 
   from = vlib_frame_vector_args (frame);
   n_left_from = frame->n_vectors;
@@ -339,6 +340,45 @@ ip4_interface_first_address (ip4_main_t * im, u32 sw_if_index,
   return result;
 }
 
+static void
+ip4_add_subnet_bcast_route (u32 fib_index,
+                            fib_prefix_t *pfx,
+                            u32 sw_if_index)
+{
+  vnet_sw_interface_flags_t iflags;
+
+  iflags = vnet_sw_interface_get_flags(vnet_get_main(), sw_if_index);
+
+  fib_table_entry_special_remove(fib_index,
+                                 pfx,
+                                 FIB_SOURCE_INTERFACE);
+
+  if (iflags & VNET_SW_INTERFACE_FLAG_DIRECTED_BCAST)
+    {
+      fib_table_entry_update_one_path (fib_index, pfx,
+                                       FIB_SOURCE_INTERFACE,
+                                       FIB_ENTRY_FLAG_NONE,
+                                       DPO_PROTO_IP4,
+                                       /* No next-hop address */
+                                       &ADJ_BCAST_ADDR,
+                                       sw_if_index,
+                                       // invalid FIB index
+                                       ~0,
+                                       1,
+                                       // no out-label stack
+                                       NULL,
+                                       FIB_ROUTE_PATH_FLAG_NONE);
+    }
+  else
+    {
+        fib_table_entry_special_add(fib_index,
+                                    pfx,
+                                    FIB_SOURCE_INTERFACE,
+                                    (FIB_ENTRY_FLAG_DROP |
+                                     FIB_ENTRY_FLAG_LOOSE_URPF_EXEMPT));
+    }
+}
+
 static void
 ip4_add_interface_routes (u32 sw_if_index,
                          ip4_main_t * im, u32 fib_index,
@@ -384,11 +424,7 @@ ip4_add_interface_routes (u32 sw_if_index,
                                      FIB_ENTRY_FLAG_LOOSE_URPF_EXEMPT));
       net_pfx.fp_addr.ip4.as_u32 |= ~im->fib_masks[pfx.fp_len];
       if (net_pfx.fp_addr.ip4.as_u32 != pfx.fp_addr.ip4.as_u32)
-        fib_table_entry_special_add(fib_index,
-                                    &net_pfx,
-                                    FIB_SOURCE_INTERFACE,
-                                    (FIB_ENTRY_FLAG_DROP |
-                                     FIB_ENTRY_FLAG_LOOSE_URPF_EXEMPT));
+        ip4_add_subnet_bcast_route(fib_index, &net_pfx, sw_if_index);
     }
   else if (pfx.fp_len == 31)
     {
@@ -636,6 +672,45 @@ ip4_add_del_interface_address (vlib_main_t * vm,
     (vm, sw_if_index, address, address_length, is_del);
 }
 
+void
+ip4_directed_broadcast (u32 sw_if_index, u8 enable)
+{
+  ip_interface_address_t *ia;
+  ip4_main_t *im;
+
+  im = &ip4_main;
+
+  /*
+   * when directed broadcast is enabled, the subnet braodcast route will forward
+   * packets using an adjacency with a broadcast MAC. otherwise it drops
+   */
+  /* *INDENT-OFF* */
+  foreach_ip_interface_address(&im->lookup_main, ia,
+                               sw_if_index, 0,
+     ({
+       if (ia->address_length <= 30)
+         {
+           ip4_address_t *ipa;
+
+           ipa = ip_interface_address_get_address (&im->lookup_main, ia);
+
+           fib_prefix_t pfx = {
+             .fp_len = 32,
+             .fp_proto = FIB_PROTOCOL_IP4,
+             .fp_addr = {
+               .ip4.as_u32 = (ipa->as_u32 | ~im->fib_masks[ia->address_length]),
+             },
+           };
+
+           ip4_add_subnet_bcast_route
+             (fib_table_get_index_for_sw_if_index(FIB_PROTOCOL_IP4,
+                                                  sw_if_index),
+              &pfx, sw_if_index);
+         }
+     }));
+  /* *INDENT-ON* */
+}
+
 /* Built-in ip4 unicast rx feature path definition */
 /* *INDENT-OFF* */
 VNET_FEATURE_ARC_INIT (ip4_unicast, static) =
@@ -1917,7 +1992,8 @@ VLIB_INIT_FUNCTION (arp_notrace_init);
 
 /* Send an ARP request to see if given destination is reachable on given interface. */
 clib_error_t *
-ip4_probe_neighbor (vlib_main_t * vm, ip4_address_t * dst, u32 sw_if_index)
+ip4_probe_neighbor (vlib_main_t * vm, ip4_address_t * dst, u32 sw_if_index,
+                   u8 refresh)
 {
   vnet_main_t *vnm = vnet_get_main ();
   ip4_main_t *im = &ip4_main;
@@ -1930,6 +2006,7 @@ ip4_probe_neighbor (vlib_main_t * vm, ip4_address_t * dst, u32 sw_if_index)
   vlib_buffer_t *b;
   adj_index_t ai;
   u32 bi = 0;
+  u8 unicast_rewrite = 0;
 
   si = vnet_get_sw_interface (vnm, sw_if_index);
 
@@ -1957,6 +2034,9 @@ ip4_probe_neighbor (vlib_main_t * vm, ip4_address_t * dst, u32 sw_if_index)
                                       &im->ip4_arp_request_packet_template,
                                       &bi);
 
+  if (!h)
+    return clib_error_return (0, "ARP request packet allocation failed");
+
   hi = vnet_get_sup_hw_interface (vnm, sw_if_index);
   if (PREDICT_FALSE (!hi->hw_address))
     {
@@ -1987,14 +2067,24 @@ ip4_probe_neighbor (vlib_main_t * vm, ip4_address_t * dst, u32 sw_if_index)
   /* Peer has been previously resolved, retrieve glean adj instead */
   if (adj->lookup_next_index == IP_LOOKUP_NEXT_REWRITE)
     {
-      adj_unlock (ai);
-      ai = adj_glean_add_or_lock (FIB_PROTOCOL_IP4,
-                                 VNET_LINK_IP4, sw_if_index, &nh);
-      adj = adj_get (ai);
+      if (refresh)
+       unicast_rewrite = 1;
+      else
+       {
+         adj_unlock (ai);
+         ai = adj_glean_add_or_lock (FIB_PROTOCOL_IP4,
+                                     VNET_LINK_IP4, sw_if_index, &nh);
+         adj = adj_get (ai);
+       }
     }
 
   /* Add encapsulation string for software interface (e.g. ethernet header). */
   vnet_rewrite_one_header (adj[0], h, sizeof (ethernet_header_t));
+  if (unicast_rewrite)
+    {
+      u16 *etype = vlib_buffer_get_current (b) - 2;
+      etype[0] = clib_host_to_net_u16 (ETHERNET_TYPE_ARP);
+    }
   vlib_buffer_advance (b, -adj->rewrite_header.data_bytes);
 
   {
@@ -2013,6 +2103,8 @@ typedef enum
 {
   IP4_REWRITE_NEXT_DROP,
   IP4_REWRITE_NEXT_ICMP_ERROR,
+  IP4_REWRITE_NEXT_FRAGMENT,
+  IP4_REWRITE_N_NEXT           /* Last */
 } ip4_rewrite_next_t;
 
 /**
@@ -2042,8 +2134,10 @@ ip4_mtu_check (vlib_buffer_t * b, u16 packet_len,
        }
       else
        {
-         /* Add support for fragmentation here */
-         *next = IP4_REWRITE_NEXT_DROP;
+         /* IP fragmentation */
+         ip_frag_set_vnet_buffer (b, 0, adj_packet_bytes,
+                                  IP4_FRAG_NEXT_IP4_LOOKUP, 0);
+         *next = IP4_REWRITE_NEXT_FRAGMENT;
        }
     }
 }
@@ -2062,7 +2156,7 @@ ip4_rewrite_inline (vlib_main_t * vm,
 
   n_left_from = frame->n_vectors;
   next_index = node->cached_next_index;
-  u32 thread_index = vlib_get_thread_index ();
+  u32 thread_index = vm->thread_index;
 
   while (n_left_from > 0)
     {
@@ -2501,6 +2595,16 @@ ip4_rewrite (vlib_main_t * vm,
     return ip4_rewrite_inline (vm, node, frame, 0, 0, 0);
 }
 
+static uword
+ip4_rewrite_bcast (vlib_main_t * vm,
+                  vlib_node_runtime_t * node, vlib_frame_t * frame)
+{
+  if (adj_are_counters_enabled ())
+    return ip4_rewrite_inline (vm, node, frame, 1, 0, 0);
+  else
+    return ip4_rewrite_inline (vm, node, frame, 0, 0, 0);
+}
+
 static uword
 ip4_midchain (vlib_main_t * vm,
              vlib_node_runtime_t * node, vlib_frame_t * frame)
@@ -2539,13 +2643,23 @@ VLIB_REGISTER_NODE (ip4_rewrite_node) = {
 
   .format_trace = format_ip4_rewrite_trace,
 
-  .n_next_nodes = 2,
+  .n_next_nodes = IP4_REWRITE_N_NEXT,
   .next_nodes = {
     [IP4_REWRITE_NEXT_DROP] = "ip4-drop",
     [IP4_REWRITE_NEXT_ICMP_ERROR] = "ip4-icmp-error",
+    [IP4_REWRITE_NEXT_FRAGMENT] = "ip4-frag",
   },
 };
-VLIB_NODE_FUNCTION_MULTIARCH (ip4_rewrite_node, ip4_rewrite)
+
+VLIB_REGISTER_NODE (ip4_rewrite_bcast_node) = {
+  .function = ip4_rewrite,
+  .name = "ip4-rewrite-bcast",
+  .vector_size = sizeof (u32),
+
+  .format_trace = format_ip4_rewrite_trace,
+  .sibling_of = "ip4-rewrite",
+};
+VLIB_NODE_FUNCTION_MULTIARCH (ip4_rewrite_bcast_node, ip4_rewrite_bcast)
 
 VLIB_REGISTER_NODE (ip4_rewrite_mcast_node) = {
   .function = ip4_rewrite_mcast,