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/ip-neighbor/ip_neighbor.api_enum.h>
20 #include <vnet/util/throttle.h>
21 #include <vnet/fib/fib_sas.h>
22 #include <vnet/ip/ip_sas.h>
25 static throttle_t nd_throttle;
27 VLIB_REGISTER_LOG_CLASS (ip6_neighbor_log, static) = {
29 .subclass_name = "neighbor",
32 #define log_debug(fmt, ...) \
33 vlib_log_debug (ip6_neighbor_log.class, fmt, __VA_ARGS__)
35 ip6_neighbor_probe_dst (u32 sw_if_index, u32 thread_index,
36 const ip6_address_t *dst)
40 if (fib_sas6_get (sw_if_index, dst, &src) ||
41 ip6_sas_by_sw_if_index (sw_if_index, dst, &src))
42 ip6_neighbor_probe (vlib_get_main (), vnet_get_main (), sw_if_index,
43 thread_index, &src, dst);
47 ip6_neighbor_advertise (vlib_main_t *vm, vnet_main_t *vnm, u32 sw_if_index,
48 u32 thread_index, const ip6_address_t *addr)
50 vnet_hw_interface_t *hi = vnet_get_sup_hw_interface (vnm, sw_if_index);
51 ip6_main_t *i6m = &ip6_main;
52 u8 *rewrite, rewrite_len;
56 addr = ip6_interface_first_address (i6m, sw_if_index);
60 log_debug ("Sending unsolicitated NA IP6 address %U on sw_if_idex %d",
61 format_ip6_address, addr, sw_if_index);
63 /* Form unsolicited neighbor advertisement packet from NS pkt template */
66 icmp6_neighbor_solicitation_header_t *h =
67 vlib_packet_template_get_packet (vm,
68 &ip6_neighbor_packet_template,
73 ip6_set_reserved_multicast_address (&h->ip.dst_address,
74 IP6_MULTICAST_SCOPE_link_local,
75 IP6_MULTICAST_GROUP_ID_all_hosts);
76 h->ip.src_address = addr[0];
77 h->neighbor.icmp.type = ICMP6_neighbor_advertisement;
78 h->neighbor.target_address = addr[0];
79 h->neighbor.advertisement_flags = clib_host_to_net_u32
80 (ICMP6_NEIGHBOR_ADVERTISEMENT_FLAG_OVERRIDE);
81 h->link_layer_option.header.type =
82 ICMP6_NEIGHBOR_DISCOVERY_OPTION_target_link_layer_address;
83 clib_memcpy (h->link_layer_option.ethernet_address,
84 hi->hw_address, vec_len (hi->hw_address));
85 h->neighbor.icmp.checksum =
86 ip6_tcp_udp_icmp_compute_checksum (vm, 0, &h->ip, &bogus_length);
87 ASSERT (bogus_length == 0);
89 /* Setup MAC header with IP6 Etype and mcast DMAC */
90 vlib_buffer_t *b = vlib_get_buffer (vm, bi);
91 ip6_multicast_ethernet_address (dst_address,
92 IP6_MULTICAST_GROUP_ID_all_hosts);
94 ethernet_build_rewrite (vnm, sw_if_index, VNET_LINK_IP6, dst_address);
95 rewrite_len = vec_len (rewrite);
96 vlib_buffer_advance (b, -rewrite_len);
97 ethernet_header_t *e = vlib_buffer_get_current (b);
98 clib_memcpy (e->dst_address, rewrite, rewrite_len);
101 /* Send unsolicited ND advertisement packet out the specified interface */
102 vnet_buffer (b)->sw_if_index[VLIB_RX] =
103 vnet_buffer (b)->sw_if_index[VLIB_TX] = sw_if_index;
104 vlib_frame_t *f = vlib_get_frame_to_node (vm, hi->output_node_index);
105 u32 *to_next = vlib_frame_vector_args (f);
108 vlib_put_frame_to_node (vm, hi->output_node_index, f);
110 vlib_increment_simple_counter (
111 &ip_neighbor_counters[AF_IP6].ipnc[VLIB_TX][IP_NEIGHBOR_CTR_GRAT],
112 thread_index, sw_if_index, 1);
119 IP6_NBR_NEXT_REPLY_TX,
121 } ip6_discover_neighbor_next_t;
124 ip6_discover_neighbor_inline (vlib_main_t * vm,
125 vlib_node_runtime_t * node,
126 vlib_frame_t * frame, int is_glean)
128 vnet_main_t *vnm = vnet_get_main ();
129 u32 *from, *to_next_drop;
130 uword n_left_from, n_left_to_next_drop;
132 u32 thread_index = vm->thread_index;
134 if (node->flags & VLIB_NODE_FLAG_TRACE)
135 ip6_forward_next_trace (vm, node, frame, VLIB_TX);
137 seed = throttle_seed (&nd_throttle, thread_index, vlib_time_now (vm));
139 from = vlib_frame_vector_args (frame);
140 n_left_from = frame->n_vectors;
142 while (n_left_from > 0)
144 vlib_get_next_frame (vm, node, IP6_NBR_NEXT_DROP,
145 to_next_drop, n_left_to_next_drop);
147 while (n_left_from > 0 && n_left_to_next_drop > 0)
149 u32 pi0, adj_index0, sw_if_index0, drop0, r0;
150 vnet_hw_interface_t *hw_if0;
151 vlib_buffer_t *p0, *b0;
152 ip_adjacency_t *adj0;
158 p0 = vlib_get_buffer (vm, pi0);
160 adj_index0 = vnet_buffer (p0)->ip.adj_index[VLIB_TX];
162 ip0 = vlib_buffer_get_current (p0);
164 adj0 = adj_get (adj_index0);
168 ip0->dst_address.as_u64[0] =
169 adj0->sub_type.nbr.next_hop.ip6.as_u64[0];
170 ip0->dst_address.as_u64[1] =
171 adj0->sub_type.nbr.next_hop.ip6.as_u64[1];
174 sw_if_index0 = adj0->rewrite_header.sw_if_index;
175 vnet_buffer (p0)->sw_if_index[VLIB_TX] = sw_if_index0;
177 /* combine the address and interface for a hash */
178 r0 = ip6_address_hash_to_u64 (&ip0->dst_address) ^ sw_if_index0;
180 drop0 = throttle_check (&nd_throttle, thread_index, r0, seed);
184 to_next_drop[0] = pi0;
186 n_left_to_next_drop -= 1;
190 p0->error = node->errors[IP6_NEIGHBOR_ERROR_THROTTLED];
194 hw_if0 = vnet_get_sup_hw_interface (vnm, sw_if_index0);
196 /* If the interface is link-down, drop the pkt */
197 if (!(hw_if0->flags & VNET_HW_INTERFACE_FLAG_LINK_UP))
200 if (!ip6_link_is_enabled (sw_if_index0))
204 * the adj has been updated to a rewrite but the node the DPO that got
205 * us here hasn't - yet. no big deal. we'll drop while we wait.
207 if (IP_LOOKUP_NEXT_REWRITE == adj0->lookup_next_index)
212 p0->error = node->errors[IP6_NEIGHBOR_ERROR_DROP];
217 * Choose source address based on destination lookup
220 const ip6_address_t *ll = ip6_get_link_local_address (sw_if_index0);
223 /* There is no address on the interface */
224 p0->error = node->errors[IP6_NEIGHBOR_ERROR_NO_SOURCE_ADDRESS];
227 ip6_address_copy (&src, ll);
229 b0 = ip6_neighbor_probe (vm, vnm, sw_if_index0, thread_index, &src,
232 if (PREDICT_TRUE (NULL != b0))
234 clib_memcpy_fast (b0->opaque2, p0->opaque2,
235 sizeof (p0->opaque2));
236 b0->flags |= p0->flags & VLIB_BUFFER_IS_TRACED;
237 b0->trace_handle = p0->trace_handle;
238 p0->error = node->errors[IP6_NEIGHBOR_ERROR_REQUEST_SENT];
242 /* There is no address on the interface */
243 p0->error = node->errors[IP6_NEIGHBOR_ERROR_NO_BUFFERS];
248 vlib_put_next_frame (vm, node, IP6_NBR_NEXT_DROP, n_left_to_next_drop);
251 return frame->n_vectors;
255 ip6_discover_neighbor (vlib_main_t * vm,
256 vlib_node_runtime_t * node, vlib_frame_t * frame)
258 return (ip6_discover_neighbor_inline (vm, node, frame, 0));
262 ip6_glean (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame)
264 return (ip6_discover_neighbor_inline (vm, node, frame, 1));
267 VLIB_REGISTER_NODE (ip6_glean_node) =
269 .function = ip6_glean,
271 .vector_size = sizeof (u32),
272 .format_trace = format_ip6_forward_next_trace,
273 .n_errors = IP6_NEIGHBOR_N_ERROR,
274 .error_counters = ip6_neighbor_error_counters,
275 .n_next_nodes = IP6_NBR_N_NEXT,
278 [IP6_NBR_NEXT_DROP] = "ip6-drop",
279 [IP6_NBR_NEXT_REPLY_TX] = "ip6-rewrite-mcast",
282 VLIB_REGISTER_NODE (ip6_discover_neighbor_node) =
284 .function = ip6_discover_neighbor,
285 .name = "ip6-discover-neighbor",
286 .vector_size = sizeof (u32),
287 .format_trace = format_ip6_forward_next_trace,
288 .n_errors = IP6_NEIGHBOR_N_ERROR,
289 .error_counters = ip6_neighbor_error_counters,
290 .n_next_nodes = IP6_NBR_N_NEXT,
293 [IP6_NBR_NEXT_DROP] = "ip6-drop",
294 [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, THROTTLE_BITS, 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")