2 * src/vnet/ip/ip_neighboor.c: ip neighbor generic handling
4 * Copyright (c) 2018 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/vnet.h>
19 #include <vnet/ip/ip.h>
20 #include <vnet/ip/ip6_neighbor.h>
21 #include <vnet/ip/ip_neighbor.h>
22 #include <vnet/ethernet/arp.h>
25 * IP neighbor scan parameter defaults are as follows:
26 * - Scan interval : 60 sec
27 * - Max processing allowed per run : 20 usec
28 * - Max probe/delete operations per run : 10
29 * - Scan interrupt delay to resume scan : 1 msec
30 * - Neighbor stale threashold : 4 x scan-interval
32 #define IP_NEIGHBOR_DEF_SCAN_INTERVAL (60.0)
33 #define IP_NEIGHBOR_DEF_MAX_PROC_TIME (20e-6)
34 #define IP_NEIGHBOR_DEF_SCAN_INT_DELAY (1e-3)
35 #define IP_NEIGHBOR_DEF_STALE (4*IP_NEIGHBOR_DEF_SCAN_INTERVAL)
36 #define IP_NEIGHBOR_DEF_MAX_UPDATE 10
40 f64 scan_interval; /* Periodic scan interval */
41 f64 max_proc_time; /* Max processing time allowed per run */
42 f64 scan_int_delay; /* Scan interrupt delay to resume scan */
43 f64 stale_threshold; /* IP neighbor stale threshod */
44 u8 max_update; /* Max probe/delete actions allowed per run */
45 u8 mode; /* IP neighbor scan mode */
46 } ip_neighbor_scan_config_t;
48 static ip_neighbor_scan_config_t ip_neighbor_scan_conf;
51 ip_neighbor_add (const ip46_address_t * ip,
53 const mac_address_t * mac,
55 ip_neighbor_flags_t flags, u32 * stats_index)
57 fib_protocol_t fproto;
62 * there's no validation here of the ND/ARP entry being added.
63 * The expectation is that the FIB will ensure that nothing bad
64 * will come of adding bogus entries.
66 if (IP46_TYPE_IP6 == type)
68 rv = vnet_set_ip6_ethernet_neighbor (vlib_get_main (),
69 sw_if_index, &ip->ip6, mac, flags);
70 fproto = FIB_PROTOCOL_IP6;
71 linkt = VNET_LINK_IP6;
75 ethernet_arp_ip4_over_ethernet_address_t a = {
81 vnet_arp_set_ip4_over_ethernet (vnet_get_main (), sw_if_index, &a,
83 fproto = FIB_PROTOCOL_IP4;
84 linkt = VNET_LINK_IP4;
87 if (0 == rv && stats_index)
88 *stats_index = adj_nbr_find (fproto, linkt, ip, sw_if_index);
94 ip_neighbor_del (const ip46_address_t * ip, ip46_type_t type, u32 sw_if_index)
98 if (IP46_TYPE_IP6 == type)
100 rv = vnet_unset_ip6_ethernet_neighbor (vlib_get_main (),
101 sw_if_index, &ip->ip6);
105 ethernet_arp_ip4_over_ethernet_address_t a = {
110 vnet_arp_unset_ip4_over_ethernet (vnet_get_main (), sw_if_index, &a);
117 ip_neighbor_scan_enable_disable (ip_neighbor_scan_arg_t * arg)
119 ip_neighbor_scan_config_t *cfg = &ip_neighbor_scan_conf;
121 cfg->mode = arg->mode;
125 cfg->scan_interval = arg->scan_interval ?
126 arg->scan_interval * 60.0 : IP_NEIGHBOR_DEF_SCAN_INTERVAL;
127 cfg->max_proc_time = arg->max_proc_time ?
128 arg->max_proc_time * 1e-6 : IP_NEIGHBOR_DEF_MAX_PROC_TIME;
129 cfg->scan_int_delay = arg->scan_int_delay ?
130 arg->scan_int_delay * 1e-3 : IP_NEIGHBOR_DEF_SCAN_INT_DELAY;
131 cfg->stale_threshold = arg->stale_threshold ?
132 arg->stale_threshold * 60.0 : cfg->scan_interval * 4;
133 cfg->max_update = arg->max_update ?
134 cfg->max_update : IP_NEIGHBOR_DEF_MAX_UPDATE;
137 cfg->scan_interval = IP_NEIGHBOR_DEF_SCAN_INTERVAL;
140 static_always_inline u32
141 ip_neighbor_scan (vlib_main_t * vm, f64 start_time, u32 start_idx,
142 u8 is_ip6, u8 delete_stale, u8 * update_count)
144 vnet_main_t *vnm = vnet_get_main ();
145 ip_neighbor_scan_config_t *cfg = &ip_neighbor_scan_conf;
146 ethernet_arp_ip4_entry_t *np4 = ip4_neighbors_pool ();
147 ip6_neighbor_t *np6 = ip6_neighbors_pool ();
148 ethernet_arp_ip4_entry_t *n4;
150 u32 curr_idx = start_idx;
152 f64 delta, update_time;
156 if (pool_is_free_index (np4, start_idx))
157 curr_idx = pool_next_index (np4, start_idx);
161 if (pool_is_free_index (np6, start_idx))
162 curr_idx = pool_next_index (np6, start_idx);
165 while (curr_idx != ~0)
167 /* allow no more than 10 neighbor updates or 20 usec of scan */
168 if ((update_count[0] >= cfg->max_update) ||
169 (((loop_count % 100) == 0) &&
170 ((vlib_time_now (vm) - start_time) > cfg->max_proc_time)))
175 n4 = pool_elt_at_index (np4, curr_idx);
176 if (n4->flags & IP_NEIGHBOR_FLAG_STATIC)
178 update_time = n4->time_last_updated;
182 n6 = pool_elt_at_index (np6, curr_idx);
183 if (n6->flags & IP_NEIGHBOR_FLAG_STATIC)
185 update_time = n6->time_last_updated;
188 delta = start_time - update_time;
189 if (delete_stale && (delta >= cfg->stale_threshold))
192 /* delete stale neighbor */
195 ethernet_arp_ip4_over_ethernet_address_t delme = {
196 .ip4.as_u32 = n4->ip4_address.as_u32,
200 vnet_arp_unset_ip4_over_ethernet (vnm, n4->sw_if_index, &delme);
204 vnet_unset_ip6_ethernet_neighbor
205 (vm, n6->key.sw_if_index, &n6->key.ip6_address);
208 else if (delta >= cfg->scan_interval)
213 ip4_probe_neighbor (vm, &n4->ip4_address, n4->sw_if_index, 1);
215 ip6_probe_neighbor (vm, &n6->key.ip6_address,
216 n6->key.sw_if_index, 1);
223 curr_idx = pool_next_index (np4, curr_idx);
225 curr_idx = pool_next_index (np6, curr_idx);
232 neighbor_scan_process (vlib_main_t * vm,
233 vlib_node_runtime_t * rt, vlib_frame_t * f)
235 ip_neighbor_scan_config_t *cfg = &ip_neighbor_scan_conf;
236 f64 timeout = IP_NEIGHBOR_DEF_SCAN_INTERVAL;
237 f64 start, next_scan = CLIB_TIME_MAX;
238 u32 ip4_nidx = 0; /* ip4 neighbor pool index */
239 u32 ip6_nidx = 0; /* ip6 neighbor pool index */
240 uword *event_data = 0;
241 u8 purge4 = 0, purge6 = 0; /* flags to purge stale entry during scan */
244 cfg->mode = IP_SCAN_DISABLED;
245 cfg->scan_interval = IP_NEIGHBOR_DEF_SCAN_INTERVAL;
246 cfg->scan_int_delay = IP_NEIGHBOR_DEF_SCAN_INTERVAL;
250 vlib_process_wait_for_event_or_clock (vm, timeout);
251 vlib_process_get_events (vm, &event_data);
252 vec_reset_length (event_data);
254 start = vlib_time_now (vm);
257 if ((ip4_nidx == 0) && (ip6_nidx == 0)) /* starting a fresh scan */
258 next_scan = start + cfg->scan_interval;
260 if ((cfg->mode & IP_SCAN_V4_NEIGHBORS) == 0)
261 ip4_nidx = ~0; /* disable ip4 neighbor scan */
263 if ((cfg->mode & IP_SCAN_V6_NEIGHBORS) == 0)
264 ip6_nidx = ~0; /* disable ip6 neighbor scan */
266 if (ip4_nidx != ~0) /* scan ip4 neighbors */
267 ip4_nidx = ip_neighbor_scan (vm, start, ip4_nidx, /* ip4 */ 0,
270 if (ip6_nidx != ~0) /* scan ip6 neighbors */
271 ip6_nidx = ip_neighbor_scan (vm, start, ip6_nidx, /* ip6 */ 1,
274 if ((ip4_nidx == ~0) && (ip6_nidx == ~0))
275 { /* scan complete */
276 timeout = next_scan - vlib_time_now (vm);
277 ip4_nidx = ip6_nidx = 0;
278 purge4 = cfg->mode & IP_SCAN_V4_NEIGHBORS;
279 purge6 = cfg->mode & IP_SCAN_V6_NEIGHBORS;
281 else /* scan incomplete */
282 timeout = cfg->scan_int_delay;
284 if (timeout > cfg->scan_interval)
285 timeout = cfg->scan_interval;
286 else if (timeout < cfg->scan_int_delay)
287 timeout = cfg->scan_int_delay;
294 VLIB_REGISTER_NODE (neighbor_scan_process_node,static) = {
295 .function = neighbor_scan_process,
296 .type = VLIB_NODE_TYPE_PROCESS,
297 .name = "ip-neighbor-scan-process",
301 static clib_error_t *
302 ip_neighbor_scan_cli (vlib_main_t * vm, unformat_input_t * input,
303 vlib_cli_command_t * cmd)
305 unformat_input_t _line_input, *line_input = &_line_input;
306 clib_error_t *error = 0;
307 u32 interval = 0, time = 0, update = 0, delay = 0, stale = 0;
308 ip_neighbor_scan_arg_t arg;
310 clib_memset (&arg, 0, sizeof (arg));
311 arg.mode = IP_SCAN_V46_NEIGHBORS;
313 /* Get a line of input. */
314 if (!unformat_user (input, unformat_line_input, line_input))
316 ip_neighbor_scan_enable_disable (&arg);
320 while (unformat_check_input (line_input) != UNFORMAT_END_OF_INPUT)
322 if (unformat (line_input, "ip4"))
323 arg.mode = IP_SCAN_V4_NEIGHBORS;
325 else if (unformat (line_input, "ip6"))
326 arg.mode = IP_SCAN_V6_NEIGHBORS;
328 else if (unformat (line_input, "both"))
329 arg.mode = IP_SCAN_V46_NEIGHBORS;
331 else if (unformat (line_input, "disable"))
332 arg.mode = IP_SCAN_DISABLED;
334 else if (unformat (line_input, "interval %d", &interval))
335 arg.scan_interval = interval;
337 else if (unformat (line_input, "max-time %d", &time))
338 arg.max_proc_time = time;
340 else if (unformat (line_input, "max-update %d", &update))
341 arg.max_update = update;
343 else if (unformat (line_input, "delay %d", &delay))
344 arg.scan_int_delay = delay;
346 else if (unformat (line_input, "stale %d", &stale))
347 arg.stale_threshold = stale;
351 error = clib_error_return (0, "unknown input '%U'",
352 format_unformat_error, line_input);
359 error = clib_error_return (0, "interval cannot exceed 255 minutes.");
364 error = clib_error_return (0, "max-time cannot exceed 255 usec.");
369 error = clib_error_return (0, "max-update cannot exceed 255.");
374 error = clib_error_return (0, "delay cannot exceed 255 msec.");
379 error = clib_error_return (0, "stale cannot exceed 255 minutes.");
383 ip_neighbor_scan_enable_disable (&arg);
386 unformat_free (line_input);
392 * The '<em>ip scan-neighbor</em>' command can be used to enable and disable
393 * periodic IP neighbor scan and change various scan parameneters.
395 * @note The default parameters used for IP neighbor scan should work fine
396 * under normal conditions. They should not be changed from the default unless
397 * properly tested to work as desied.
400 * Example of enabling IP neighbor scan:
401 * @cliexcmd{ip neighbor-scan enable}
404 VLIB_CLI_COMMAND (ip_scan_neighbor_command, static) = {
405 .path = "ip scan-neighbor",
406 .function = ip_neighbor_scan_cli,
407 .short_help = "ip scan-neighbor [ip4|ip6|both|disable] [interval <n-min>] [max-time <n-usec>] [max-update <n>] [delay <n-msec>] [stale <n-min>]",
413 format_ip_scan_mode (u8 * s, va_list * args)
415 u8 mode = va_arg (*args, u32);
418 case IP_SCAN_V4_NEIGHBORS:
419 return format (s, "IPv4");
420 case IP_SCAN_V6_NEIGHBORS:
421 return format (s, "IPv6");
422 case IP_SCAN_V46_NEIGHBORS:
423 return format (s, "IPv4 and IPv6");
425 return format (s, "unknown");
428 static clib_error_t *
429 show_ip_neighbor_scan (vlib_main_t * vm, unformat_input_t * input,
430 vlib_cli_command_t * cmd)
432 ip_neighbor_scan_config_t *cfg = &ip_neighbor_scan_conf;
436 "IP neighbor scan disabled - current time is %.4f sec",
439 vlib_cli_output (vm, "IP neighbor scan enabled for %U neighbors - "
440 "current time is %.4f sec\n "
441 "Full_scan_interval: %f min "
442 "Stale_purge_threshod: %f min\n "
443 "Max_process_time: %f usec Max_updates %d "
444 "Delay_to_resume_after_max_limit: %f msec",
445 format_ip_scan_mode, cfg->mode,
446 vlib_time_now (vm), cfg->scan_interval / 60.0,
447 cfg->stale_threshold / 60.0, cfg->max_proc_time / 1e-6,
448 cfg->max_update, cfg->scan_int_delay / 1e-3);
453 * The '<em>show ip scan-neighbor</em>' command can be used to show the current
454 * periodic IP neighbor scan parameters
457 * Example of showing IP neighbor scan current parameters:
458 * @cliexcmd{show ip neighbor-scan}
461 VLIB_CLI_COMMAND (show_ip_scan_neighbor_command, static) = {
462 .path = "show ip scan-neighbor",
463 .function = show_ip_neighbor_scan,
464 .short_help = "show ip scan-neighbor",
470 * fd.io coding-style-patch-verification: ON
473 * eval: (c-set-style "gnu")