FD.io VPP  v19.04.4-rc0-5-ge88582fac
Vector Packet Processing
ip_neighbor.c
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1 /*
2  * src/vnet/ip/ip_neighboor.c: ip neighbor generic handling
3  *
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:
8  *
9  * http://www.apache.org/licenses/LICENSE-2.0
10  *
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.
16  */
17 
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>
23 
24 /*
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
31  */
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
37 
38 typedef struct
39 {
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 */
47 
49 
50 int
51 ip_neighbor_add (const ip46_address_t * ip,
52  ip46_type_t type,
53  const mac_address_t * mac,
55  ip_neighbor_flags_t flags, u32 * stats_index)
56 {
57  fib_protocol_t fproto;
58  vnet_link_t linkt;
59  int rv;
60 
61  /*
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.
65  */
66  if (IP46_TYPE_IP6 == type)
67  {
69  sw_if_index, &ip->ip6, mac, flags);
70  fproto = FIB_PROTOCOL_IP6;
71  linkt = VNET_LINK_IP6;
72  }
73  else
74  {
75  ethernet_arp_ip4_over_ethernet_address_t a = {
76  .ip4 = ip->ip4,
77  .mac = *mac,
78  };
79 
80  rv =
81  vnet_arp_set_ip4_over_ethernet (vnet_get_main (), sw_if_index, &a,
82  flags);
83  fproto = FIB_PROTOCOL_IP4;
84  linkt = VNET_LINK_IP4;
85  }
86 
87  if (0 == rv && stats_index)
88  *stats_index = adj_nbr_find (fproto, linkt, ip, sw_if_index);
89 
90  return (rv);
91 }
92 
93 int
94 ip_neighbor_del (const ip46_address_t * ip, ip46_type_t type, u32 sw_if_index)
95 {
96  int rv;
97 
98  if (IP46_TYPE_IP6 == type)
99  {
101  sw_if_index, &ip->ip6);
102  }
103  else
104  {
105  ethernet_arp_ip4_over_ethernet_address_t a = {
106  .ip4 = ip->ip4,
107  };
108 
109  rv =
110  vnet_arp_unset_ip4_over_ethernet (vnet_get_main (), sw_if_index, &a);
111  }
112 
113  return (rv);
114 }
115 
116 void
118 {
120 
121  cfg->mode = arg->mode;
122 
123  if (arg->mode)
124  {
125  cfg->scan_interval = arg->scan_interval ?
127  cfg->max_proc_time = arg->max_proc_time ?
129  cfg->scan_int_delay = arg->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 ?
135  }
136  else
138 }
139 
141 ip_neighbor_scan (vlib_main_t * vm, f64 start_time, u32 start_idx,
142  u8 is_ip6, u8 delete_stale, u8 * update_count)
143 {
144  vnet_main_t *vnm = vnet_get_main ();
149  ip6_neighbor_t *n6;
150  u32 curr_idx = start_idx;
151  u32 loop_count = 0;
152  f64 delta, update_time;
153 
154  if (!is_ip6)
155  {
156  if (pool_is_free_index (np4, start_idx))
157  curr_idx = pool_next_index (np4, start_idx);
158  }
159  else
160  {
161  if (pool_is_free_index (np6, start_idx))
162  curr_idx = pool_next_index (np6, start_idx);
163  }
164 
165  while (curr_idx != ~0)
166  {
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)))
171  break;
172 
173  if (!is_ip6)
174  {
175  n4 = pool_elt_at_index (np4, curr_idx);
176  if (n4->flags & IP_NEIGHBOR_FLAG_STATIC)
177  goto next_neighbor;
178  update_time = n4->time_last_updated;
179  }
180  else
181  {
182  n6 = pool_elt_at_index (np6, curr_idx);
183  if (n6->flags & IP_NEIGHBOR_FLAG_STATIC)
184  goto next_neighbor;
185  update_time = n6->time_last_updated;
186  }
187 
188  delta = start_time - update_time;
189  if (delete_stale && (delta >= cfg->stale_threshold))
190  {
191  update_count[0]++;
192  /* delete stale neighbor */
193  if (!is_ip6)
194  {
195  ethernet_arp_ip4_over_ethernet_address_t delme = {
196  .ip4.as_u32 = n4->ip4_address.as_u32,
197  .mac = n4->mac,
198  };
199 
201  }
202  else
203  {
205  (vm, n6->key.sw_if_index, &n6->key.ip6_address);
206  }
207  }
208  else if (delta >= cfg->scan_interval)
209  {
210  update_count[0]++;
211  /* probe neighbor */
212  if (!is_ip6)
213  ip4_probe_neighbor (vm, &n4->ip4_address, n4->sw_if_index, 1);
214  else
216  n6->key.sw_if_index, 1);
217  }
218 
219  next_neighbor:
220  loop_count++;
221 
222  if (!is_ip6)
223  curr_idx = pool_next_index (np4, curr_idx);
224  else
225  curr_idx = pool_next_index (np6, curr_idx);
226  }
227 
228  return curr_idx;
229 }
230 
231 static uword
234 {
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 */
242  u8 update;
243 
244  cfg->mode = IP_SCAN_DISABLED;
247 
248  while (1)
249  {
251  vlib_process_get_events (vm, &event_data);
252  vec_reset_length (event_data);
253 
254  start = vlib_time_now (vm);
255  update = 0;
256 
257  if ((ip4_nidx == 0) && (ip6_nidx == 0)) /* starting a fresh scan */
258  next_scan = start + cfg->scan_interval;
259 
260  if ((cfg->mode & IP_SCAN_V4_NEIGHBORS) == 0)
261  ip4_nidx = ~0; /* disable ip4 neighbor scan */
262 
263  if ((cfg->mode & IP_SCAN_V6_NEIGHBORS) == 0)
264  ip6_nidx = ~0; /* disable ip6 neighbor scan */
265 
266  if (ip4_nidx != ~0) /* scan ip4 neighbors */
267  ip4_nidx = ip_neighbor_scan (vm, start, ip4_nidx, /* ip4 */ 0,
268  purge4, &update);
269 
270  if (ip6_nidx != ~0) /* scan ip6 neighbors */
271  ip6_nidx = ip_neighbor_scan (vm, start, ip6_nidx, /* ip6 */ 1,
272  purge6, &update);
273 
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;
280  }
281  else /* scan incomplete */
282  timeout = cfg->scan_int_delay;
283 
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;
288 
289  }
290  return 0;
291 }
292 
293 /* *INDENT-OFF* */
295  .function = neighbor_scan_process,
296  .type = VLIB_NODE_TYPE_PROCESS,
297  .name = "ip-neighbor-scan-process",
298 };
299 /* *INDENT-ON* */
300 
301 static clib_error_t *
303  vlib_cli_command_t * cmd)
304 {
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;
309 
310  clib_memset (&arg, 0, sizeof (arg));
312 
313  /* Get a line of input. */
314  if (!unformat_user (input, unformat_line_input, line_input))
315  {
317  return error;
318  }
319 
320  while (unformat_check_input (line_input) != UNFORMAT_END_OF_INPUT)
321  {
322  if (unformat (line_input, "ip4"))
324 
325  else if (unformat (line_input, "ip6"))
327 
328  else if (unformat (line_input, "both"))
330 
331  else if (unformat (line_input, "disable"))
332  arg.mode = IP_SCAN_DISABLED;
333 
334  else if (unformat (line_input, "interval %d", &interval))
335  arg.scan_interval = interval;
336 
337  else if (unformat (line_input, "max-time %d", &time))
338  arg.max_proc_time = time;
339 
340  else if (unformat (line_input, "max-update %d", &update))
341  arg.max_update = update;
342 
343  else if (unformat (line_input, "delay %d", &delay))
344  arg.scan_int_delay = delay;
345 
346  else if (unformat (line_input, "stale %d", &stale))
347  arg.stale_threshold = stale;
348 
349  else
350  {
351  error = clib_error_return (0, "unknown input '%U'",
352  format_unformat_error, line_input);
353  goto done;
354  }
355  }
356 
357  if (interval > 255)
358  {
359  error = clib_error_return (0, "interval cannot exceed 255 minutes.");
360  goto done;
361  }
362  if (time > 255)
363  {
364  error = clib_error_return (0, "max-time cannot exceed 255 usec.");
365  goto done;
366  }
367  if (update > 255)
368  {
369  error = clib_error_return (0, "max-update cannot exceed 255.");
370  goto done;
371  }
372  if (delay > 255)
373  {
374  error = clib_error_return (0, "delay cannot exceed 255 msec.");
375  goto done;
376  }
377  if (stale > 255)
378  {
379  error = clib_error_return (0, "stale cannot exceed 255 minutes.");
380  goto done;
381  }
382 
384 
385 done:
386  unformat_free (line_input);
387 
388  return error;
389 }
390 
391 /*?
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.
394  *
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.
398  *
399  * @cliexpar
400  * Example of enabling IP neighbor scan:
401  * @cliexcmd{ip neighbor-scan enable}
402 ?*/
403 /* *INDENT-OFF* */
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>]",
408  .is_mp_safe = 1,
409 };
410 /* *INDENT-ON* */
411 
412 static u8 *
413 format_ip_scan_mode (u8 * s, va_list * args)
414 {
415  u8 mode = va_arg (*args, u32);
416  switch (mode)
417  {
419  return format (s, "IPv4");
421  return format (s, "IPv6");
423  return format (s, "IPv4 and IPv6");
424  }
425  return format (s, "unknown");
426 }
427 
428 static clib_error_t *
430  vlib_cli_command_t * cmd)
431 {
433 
434  if (cfg->mode == 0)
435  vlib_cli_output (vm,
436  "IP neighbor scan disabled - current time is %.4f sec",
437  vlib_time_now (vm));
438  else
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",
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);
449  return 0;
450 }
451 
452 /*?
453  * The '<em>show ip scan-neighbor</em>' command can be used to show the current
454  * periodic IP neighbor scan parameters
455  *
456  * @cliexpar
457  * Example of showing IP neighbor scan current parameters:
458  * @cliexcmd{show ip neighbor-scan}
459 ?*/
460 /* *INDENT-OFF* */
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",
465  .is_mp_safe = 1,
466 };
467 /* *INDENT-ON* */
468 
469 /*
470  * fd.io coding-style-patch-verification: ON
471  *
472  * Local Variables:
473  * eval: (c-set-style "gnu")
474  * End:
475  */
ip_neighbor_flags_t flags
Definition: arp.h:31
u32 sw_if_index
Definition: ipsec_gre.api:37
int vnet_arp_set_ip4_over_ethernet(vnet_main_t *vnm, u32 sw_if_index, const ethernet_arp_ip4_over_ethernet_address_t *a, ip_neighbor_flags_t flags)
Definition: arp.c:1966
#define pool_next_index(P, I)
Return next occupied pool index after i, useful for safe iteration.
Definition: pool.h:522
u32 flags
Definition: vhost_user.h:115
#define IP_NEIGHBOR_DEF_MAX_UPDATE
Definition: ip_neighbor.c:36
static f64 vlib_process_wait_for_event_or_clock(vlib_main_t *vm, f64 dt)
Suspend a cooperative multi-tasking thread Waits for an event, or for the indicated number of seconds...
Definition: node_funcs.h:673
a
Definition: bitmap.h:538
int vnet_arp_unset_ip4_over_ethernet(vnet_main_t *vnm, u32 sw_if_index, const ethernet_arp_ip4_over_ethernet_address_t *a)
Control Plane hook to remove an ARP entry.
Definition: arp.c:1553
vnet_main_t * vnet_get_main(void)
Definition: misc.c:47
int ip_neighbor_add(const ip46_address_t *ip, ip46_type_t type, const mac_address_t *mac, u32 sw_if_index, ip_neighbor_flags_t flags, u32 *stats_index)
Definition: ip_neighbor.c:51
clib_memset(h->entries, 0, sizeof(h->entries[0]) *entries)
static f64 vlib_time_now(vlib_main_t *vm)
Definition: main.h:255
#define IP_SCAN_V6_NEIGHBORS
Definition: ip_neighbor.h:23
uword unformat_user(unformat_input_t *input, unformat_function_t *func,...)
Definition: unformat.c:983
u8 * format(u8 *s, const char *fmt,...)
Definition: format.c:424
#define IP_SCAN_V46_NEIGHBORS
Definition: ip_neighbor.h:24
static ip_neighbor_scan_config_t ip_neighbor_scan_conf
Definition: ip_neighbor.c:48
unsigned char u8
Definition: types.h:56
#define IP_NEIGHBOR_DEF_SCAN_INTERVAL
Definition: ip_neighbor.c:32
enum fib_protocol_t_ fib_protocol_t
Protocol Type.
#define vec_reset_length(v)
Reset vector length to zero NULL-pointer tolerant.
double f64
Definition: types.h:142
int ip_neighbor_del(const ip46_address_t *ip, ip46_type_t type, u32 sw_if_index)
Definition: ip_neighbor.c:94
ip6_neighbor_t * ip6_neighbors_pool(void)
Definition: ip6_neighbor.c:990
#define static_always_inline
Definition: clib.h:99
void ip_neighbor_scan_enable_disable(ip_neighbor_scan_arg_t *arg)
Definition: ip_neighbor.c:117
static uword vlib_process_get_events(vlib_main_t *vm, uword **data_vector)
Return the first event type which has occurred and a vector of per-event data of that type...
Definition: node_funcs.h:516
enum ip_neighbor_flags_t_ ip_neighbor_flags_t
#define clib_error_return(e, args...)
Definition: error.h:99
#define IP_SCAN_V4_NEIGHBORS
Definition: ip_neighbor.h:22
unsigned int u32
Definition: types.h:88
clib_error_t * ip6_probe_neighbor(vlib_main_t *vm, ip6_address_t *dst, u32 sw_if_index, u8 refresh)
Definition: ip6_forward.c:1486
#define IP_NEIGHBOR_DEF_MAX_PROC_TIME
Definition: ip_neighbor.c:33
unformat_function_t unformat_line_input
Definition: format.h:282
#define pool_elt_at_index(p, i)
Returns pointer to element at given index.
Definition: pool.h:514
static clib_error_t * show_ip_neighbor_scan(vlib_main_t *vm, unformat_input_t *input, vlib_cli_command_t *cmd)
Definition: ip_neighbor.c:429
ip4_address_t ip4_address
Definition: arp.h:27
mac_address_t mac
Definition: arp.h:29
struct _unformat_input_t unformat_input_t
u32 sw_if_index
Definition: arp.h:26
ethernet_arp_ip4_entry_t * ip4_neighbors_pool(void)
Definition: arp.c:1387
#define IP_SCAN_DISABLED
Definition: ip_neighbor.h:21
clib_error_t * ip4_probe_neighbor(vlib_main_t *vm, ip4_address_t *dst, u32 sw_if_index, u8 refresh)
Definition: ip4_forward.c:1996
#define VLIB_REGISTER_NODE(x,...)
Definition: node.h:169
#define UNFORMAT_END_OF_INPUT
Definition: format.h:144
vlib_main_t * vm
Definition: buffer.c:312
static vlib_node_registration_t neighbor_scan_process_node
(constructor) VLIB_REGISTER_NODE (neighbor_scan_process_node)
Definition: ip_neighbor.c:294
#define pool_is_free_index(P, I)
Use free bitmap to query whether given index is free.
Definition: pool.h:283
static_always_inline u32 ip_neighbor_scan(vlib_main_t *vm, f64 start_time, u32 start_idx, u8 is_ip6, u8 delete_stale, u8 *update_count)
Definition: ip_neighbor.c:141
vl_api_vxlan_gbp_api_tunnel_mode_t mode
Definition: vxlan_gbp.api:44
#define VLIB_CLI_COMMAND(x,...)
Definition: cli.h:155
ip6_address_t ip6_address
Definition: ip6_neighbor.h:28
enum vnet_link_t_ vnet_link_t
Link Type: A description of the protocol of packets on the link.
ip46_type_t
Definition: ip6_packet.h:70
#define CLIB_TIME_MAX
Definition: time.h:212
int vnet_set_ip6_ethernet_neighbor(vlib_main_t *vm, u32 sw_if_index, const ip6_address_t *a, const mac_address_t *mac, ip_neighbor_flags_t flags)
Definition: ip6_neighbor.c:772
static uword neighbor_scan_process(vlib_main_t *vm, vlib_node_runtime_t *rt, vlib_frame_t *f)
Definition: ip_neighbor.c:232
static vlib_main_t * vlib_get_main(void)
Definition: global_funcs.h:23
f64 time_last_updated
Definition: arp.h:33
static u8 * format_ip_scan_mode(u8 *s, va_list *args)
Definition: ip_neighbor.c:413
int vnet_unset_ip6_ethernet_neighbor(vlib_main_t *vm, u32 sw_if_index, const ip6_address_t *a)
Definition: ip6_neighbor.c:924
ip6_neighbor_key_t key
Definition: ip6_neighbor.h:35
u64 uword
Definition: types.h:112
static void unformat_free(unformat_input_t *i)
Definition: format.h:162
u8 * format_unformat_error(u8 *s, va_list *va)
Definition: unformat.c:91
ip_neighbor_flags_t flags
Definition: ip6_neighbor.h:37
vl_api_mac_address_t mac
Definition: gbp.api:120
void vlib_cli_output(vlib_main_t *vm, char *fmt,...)
Definition: cli.c:762
static clib_error_t * ip_neighbor_scan_cli(vlib_main_t *vm, unformat_input_t *input, vlib_cli_command_t *cmd)
Definition: ip_neighbor.c:302
#define IP_NEIGHBOR_DEF_SCAN_INT_DELAY
Definition: ip_neighbor.c:34
uword unformat(unformat_input_t *i, const char *fmt,...)
Definition: unformat.c:972
static uword unformat_check_input(unformat_input_t *i)
Definition: format.h:170
Definition: arp.h:24
adj_index_t adj_nbr_find(fib_protocol_t nh_proto, vnet_link_t link_type, const ip46_address_t *nh_addr, u32 sw_if_index)
Lookup neighbor adjancency.
Definition: adj_nbr.c:99