2 * ip/ip6_neighbor.c: IP6 neighbor handling
4 * Copyright (c) 2010 Cisco and/or its affiliates.
5 * Licensed under the Apache License, Version 2.0 (the "License");
6 * you may not use this file except in compliance with the License.
7 * You may obtain a copy of the License at:
9 * http://www.apache.org/licenses/LICENSE-2.0
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
18 #include <vnet/ip-neighbor/ip6_neighbor.h>
19 #include <vnet/util/throttle.h>
22 static throttle_t nd_throttle;
25 ip6_neighbor_probe_dst (const ip_adjacency_t * adj, const ip6_address_t * dst)
27 ip_interface_address_t *ia;
30 src = ip6_interface_address_matching_destination
31 (&ip6_main, dst, adj->rewrite_header.sw_if_index, &ia);
36 ip6_neighbor_probe (vlib_get_main (), vnet_get_main (), adj, src, dst);
40 ip6_neighbor_advertise (vlib_main_t * vm,
42 u32 sw_if_index, const ip6_address_t * addr)
44 vnet_hw_interface_t *hi = vnet_get_sup_hw_interface (vnm, sw_if_index);
45 ip6_main_t *i6m = &ip6_main;
46 u8 *rewrite, rewrite_len;
50 addr = ip6_interface_first_address (i6m, sw_if_index);
55 ("Sending unsolicitated NA IP6 address %U on sw_if_idex %d",
56 format_ip6_address, addr, sw_if_index);
58 /* Form unsolicited neighbor advertisement packet from NS pkt template */
61 icmp6_neighbor_solicitation_header_t *h =
62 vlib_packet_template_get_packet (vm,
63 &ip6_neighbor_packet_template,
68 ip6_set_reserved_multicast_address (&h->ip.dst_address,
69 IP6_MULTICAST_SCOPE_link_local,
70 IP6_MULTICAST_GROUP_ID_all_hosts);
71 h->ip.src_address = addr[0];
72 h->neighbor.icmp.type = ICMP6_neighbor_advertisement;
73 h->neighbor.target_address = addr[0];
74 h->neighbor.advertisement_flags = clib_host_to_net_u32
75 (ICMP6_NEIGHBOR_ADVERTISEMENT_FLAG_OVERRIDE);
76 h->link_layer_option.header.type =
77 ICMP6_NEIGHBOR_DISCOVERY_OPTION_target_link_layer_address;
78 clib_memcpy (h->link_layer_option.ethernet_address,
79 hi->hw_address, vec_len (hi->hw_address));
80 h->neighbor.icmp.checksum =
81 ip6_tcp_udp_icmp_compute_checksum (vm, 0, &h->ip, &bogus_length);
82 ASSERT (bogus_length == 0);
84 /* Setup MAC header with IP6 Etype and mcast DMAC */
85 vlib_buffer_t *b = vlib_get_buffer (vm, bi);
86 ip6_multicast_ethernet_address (dst_address,
87 IP6_MULTICAST_GROUP_ID_all_hosts);
89 ethernet_build_rewrite (vnm, sw_if_index, VNET_LINK_IP6, dst_address);
90 rewrite_len = vec_len (rewrite);
91 vlib_buffer_advance (b, -rewrite_len);
92 ethernet_header_t *e = vlib_buffer_get_current (b);
93 clib_memcpy (e->dst_address, rewrite, rewrite_len);
96 /* Send unsolicited ND advertisement packet out the specified interface */
97 vnet_buffer (b)->sw_if_index[VLIB_RX] =
98 vnet_buffer (b)->sw_if_index[VLIB_TX] = sw_if_index;
99 vlib_frame_t *f = vlib_get_frame_to_node (vm, hi->output_node_index);
100 u32 *to_next = vlib_frame_vector_args (f);
103 vlib_put_frame_to_node (vm, hi->output_node_index, f);
110 IP6_NBR_NEXT_REPLY_TX,
112 } ip6_discover_neighbor_next_t;
117 IP6_NBR_ERROR_REQUEST_SENT,
118 IP6_NBR_ERROR_NO_SOURCE_ADDRESS,
119 IP6_NBR_ERROR_NO_BUFFERS,
120 } ip6_discover_neighbor_error_t;
123 ip6_discover_neighbor_inline (vlib_main_t * vm,
124 vlib_node_runtime_t * node,
125 vlib_frame_t * frame, int is_glean)
127 vnet_main_t *vnm = vnet_get_main ();
128 u32 *from, *to_next_drop;
129 uword n_left_from, n_left_to_next_drop;
131 u32 thread_index = vm->thread_index;
133 if (node->flags & VLIB_NODE_FLAG_TRACE)
134 ip6_forward_next_trace (vm, node, frame, VLIB_TX);
136 seed = throttle_seed (&nd_throttle, thread_index, vlib_time_now (vm));
138 from = vlib_frame_vector_args (frame);
139 n_left_from = frame->n_vectors;
141 while (n_left_from > 0)
143 vlib_get_next_frame (vm, node, IP6_NBR_NEXT_DROP,
144 to_next_drop, n_left_to_next_drop);
146 while (n_left_from > 0 && n_left_to_next_drop > 0)
148 u32 pi0, adj_index0, sw_if_index0, drop0, r0;
149 vnet_hw_interface_t *hw_if0;
150 vlib_buffer_t *p0, *b0;
151 ip_adjacency_t *adj0;
157 p0 = vlib_get_buffer (vm, pi0);
159 adj_index0 = vnet_buffer (p0)->ip.adj_index[VLIB_TX];
161 ip0 = vlib_buffer_get_current (p0);
163 adj0 = adj_get (adj_index0);
167 ip0->dst_address.as_u64[0] =
168 adj0->sub_type.nbr.next_hop.ip6.as_u64[0];
169 ip0->dst_address.as_u64[1] =
170 adj0->sub_type.nbr.next_hop.ip6.as_u64[1];
173 sw_if_index0 = adj0->rewrite_header.sw_if_index;
174 vnet_buffer (p0)->sw_if_index[VLIB_TX] = sw_if_index0;
176 /* combine the address and interface for a hash */
177 r0 = ip6_address_hash_to_u64 (&ip0->dst_address) ^ sw_if_index0;
179 drop0 = throttle_check (&nd_throttle, thread_index, r0, seed);
183 to_next_drop[0] = pi0;
185 n_left_to_next_drop -= 1;
187 hw_if0 = vnet_get_sup_hw_interface (vnm, sw_if_index0);
189 /* If the interface is link-down, drop the pkt */
190 if (!(hw_if0->flags & VNET_HW_INTERFACE_FLAG_LINK_UP))
193 if (!ip6_link_is_enabled (sw_if_index0))
197 * the adj has been updated to a rewrite but the node the DPO that got
198 * us here hasn't - yet. no big deal. we'll drop while we wait.
200 if (IP_LOOKUP_NEXT_REWRITE == adj0->lookup_next_index)
205 p0->error = node->errors[IP6_NBR_ERROR_DROP];
210 * Choose source address based on destination lookup
213 if (!ip6_src_address_for_packet (sw_if_index0,
214 &ip0->dst_address, &src))
216 /* There is no address on the interface */
217 p0->error = node->errors[IP6_NBR_ERROR_NO_SOURCE_ADDRESS];
221 b0 = ip6_neighbor_probe (vm, vnm, adj0, &src, &ip0->dst_address);
223 if (PREDICT_TRUE (NULL != b0))
225 clib_memcpy_fast (b0->opaque2, p0->opaque2,
226 sizeof (p0->opaque2));
227 b0->flags |= p0->flags & VLIB_BUFFER_IS_TRACED;
228 b0->trace_handle = p0->trace_handle;
229 p0->error = node->errors[IP6_NBR_ERROR_REQUEST_SENT];
233 /* There is no address on the interface */
234 p0->error = node->errors[IP6_NBR_ERROR_NO_BUFFERS];
239 vlib_put_next_frame (vm, node, IP6_NBR_NEXT_DROP, n_left_to_next_drop);
242 return frame->n_vectors;
246 ip6_discover_neighbor (vlib_main_t * vm,
247 vlib_node_runtime_t * node, vlib_frame_t * frame)
249 return (ip6_discover_neighbor_inline (vm, node, frame, 0));
253 ip6_glean (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame)
255 return (ip6_discover_neighbor_inline (vm, node, frame, 1));
258 static char *ip6_discover_neighbor_error_strings[] = {
259 [IP6_NBR_ERROR_DROP] = "address overflow drops",
260 [IP6_NBR_ERROR_REQUEST_SENT] = "neighbor solicitations sent",
261 [IP6_NBR_ERROR_NO_SOURCE_ADDRESS] = "no source address for ND solicitation",
262 [IP6_NBR_ERROR_NO_BUFFERS] = "no buffers",
266 VLIB_REGISTER_NODE (ip6_glean_node) =
268 .function = ip6_glean,
270 .vector_size = sizeof (u32),
271 .format_trace = format_ip6_forward_next_trace,
272 .n_errors = ARRAY_LEN (ip6_discover_neighbor_error_strings),
273 .error_strings = ip6_discover_neighbor_error_strings,
274 .n_next_nodes = IP6_NBR_N_NEXT,
277 [IP6_NBR_NEXT_DROP] = "ip6-drop",
278 [IP6_NBR_NEXT_REPLY_TX] = "ip6-rewrite-mcast",
281 VLIB_REGISTER_NODE (ip6_discover_neighbor_node) =
283 .function = ip6_discover_neighbor,
284 .name = "ip6-discover-neighbor",
285 .vector_size = sizeof (u32),
286 .format_trace = format_ip6_forward_next_trace,
287 .n_errors = ARRAY_LEN (ip6_discover_neighbor_error_strings),
288 .error_strings = ip6_discover_neighbor_error_strings,
289 .n_next_nodes = IP6_NBR_N_NEXT,
292 [IP6_NBR_NEXT_DROP] = "ip6-drop",
293 [IP6_NBR_NEXT_REPLY_TX] = "ip6-rewrite-mcast",
298 /* Template used to generate IP6 neighbor solicitation packets. */
299 vlib_packet_template_t ip6_neighbor_packet_template;
301 static clib_error_t *
302 ip6_neighbor_init (vlib_main_t * vm)
304 icmp6_neighbor_solicitation_header_t p;
306 clib_memset (&p, 0, sizeof (p));
308 p.ip.ip_version_traffic_class_and_flow_label =
309 clib_host_to_net_u32 (0x6 << 28);
310 p.ip.payload_length =
311 clib_host_to_net_u16 (sizeof (p) -
313 (icmp6_neighbor_solicitation_header_t, neighbor));
314 p.ip.protocol = IP_PROTOCOL_ICMP6;
315 p.ip.hop_limit = 255;
316 ip6_set_solicited_node_multicast_address (&p.ip.dst_address, 0);
318 p.neighbor.icmp.type = ICMP6_neighbor_solicitation;
320 p.link_layer_option.header.type =
321 ICMP6_NEIGHBOR_DISCOVERY_OPTION_source_link_layer_address;
322 p.link_layer_option.header.n_data_u64s =
323 sizeof (p.link_layer_option) / sizeof (u64);
325 vlib_packet_template_init (vm,
326 &ip6_neighbor_packet_template, &p, sizeof (p),
327 /* alloc chunk size */ 8,
328 "ip6 neighbor discovery");
333 VLIB_INIT_FUNCTION (ip6_neighbor_init);
335 static clib_error_t *
336 ip6_nd_main_loop_enter (vlib_main_t * vm)
338 vlib_thread_main_t *tm = &vlib_thread_main;
340 throttle_init (&nd_throttle, tm->n_vlib_mains, 1e-3);
345 VLIB_MAIN_LOOP_ENTER_FUNCTION (ip6_nd_main_loop_enter);
348 * fd.io coding-style-patch-verification: ON
351 * eval: (c-set-style "gnu")