summaryrefslogtreecommitdiffstats
path: root/src/vnet/srv6/sr_steering.c
blob: 57fe21f674641277595951f299d9b9899104c99b (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
/*
 * sr_steering.c: ipv6 segment routing steering into SR policy
 *
 * Copyright (c) 2016 Cisco and/or its affiliates.
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at:
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

/**
 * @file
 * @brief Packet steering into SR Policies
 *
 * This file is in charge of handling the FIB appropiatly to steer packets
 * through SR Policies as defined in 'sr_policy_rewrite.c'. Notice that here
 * we are only doing steering. SR policy application is done in
 * sr_policy_rewrite.c
 *
 * Supports:
 *  - Steering of IPv6 traffic Destination Address based
 *  - Steering of IPv4 traffic Destination Address based
 *  - Steering of L2 frames, interface based (sw interface)
 */

#include <vlib/vlib.h>
#include <vnet/vnet.h>
#include <vnet/srv6/sr.h>
#include <vnet/ip/ip.h>
#include <vnet/srv6/sr_packet.h>
#include <vnet/ip/ip6_packet.h>
#include <vnet/fib/ip6_fib.h>
#include <vnet/dpo/dpo.h>

#include <vppinfra/error.h>
#include <vppinfra/elog.h>

/**
 * @brief Steer traffic L2 and L3 traffic through a given SR policy
 *
 * @param is_del
 * @param bsid is the bindingSID of the SR Policy (alt to sr_policy_index)
 * @param sr_policy is the index of the SR Policy (alt to bsid)
 * @param table_id is the VRF where to install the FIB entry for the BSID
 * @param prefix is the IPv4/v6 address for L3 traffic type
 * @param mask_width is the mask for L3 traffic type
 * @param sw_if_index is the incoming interface for L2 traffic
 * @param traffic_type describes the type of traffic
 *
 * @return 0 if correct, else error
 */
int
sr_steering_policy (int is_del, ip6_address_t * bsid, u32 sr_policy_index,
		    u32 table_id, ip46_address_t * prefix, u32 mask_width,
		    u32 sw_if_index, u8 traffic_type)
{
  ip6_sr_main_t *sm = &sr_main;
  sr_steering_key_t key;
  ip6_sr_steering_policy_t *steer_pl;
  fib_prefix_t pfx = { 0 };

  ip6_sr_policy_t *sr_policy = 0;
  uword *p = 0;

  memset (&key, 0, sizeof (sr_steering_key_t));

  /* Compute the steer policy key */
  if (traffic_type == SR_STEER_IPV4 || traffic_type == SR_STEER_IPV6)
    {
      key.l3.prefix.as_u64[0] = prefix->as_u64[0];
      key.l3.prefix.as_u64[1] = prefix->as_u64[1];
      key.l3.mask_width = mask_width;
      key.l3.fib_table = (table_id != (u32) ~ 0 ? table_id : 0);
    }
  else if (traffic_type == SR_STEER_L2)
    {
      key.l2.sw_if_index = sw_if_index;

      /* Sanitise the SW_IF_INDEX */
      if (pool_is_free_index (sm->vnet_main->interface_main.sw_interfaces,
			      sw_if_index))
	return -3;

      vnet_sw_interface_t *sw =
	vnet_get_sw_interface (sm->vnet_main, sw_if_index);
      if (sw->type != VNET_SW_INTERFACE_TYPE_HARDWARE)
	return -3;
    }
  else
    return -1;

  key.traffic_type = traffic_type;

  /* Search for the item */
  p = mhash_get (&sm->sr_steer_policies_hash, &key);

  if (p)
    {
      /* Retrieve Steer Policy function */
      steer_pl = pool_elt_at_index (sm->steer_policies, p[0]);

      if (is_del)
	{
	  if (steer_pl->classify.traffic_type == SR_STEER_IPV6)
	    {
	      /* Remove FIB entry */
	      pfx.fp_proto = FIB_PROTOCOL_IP6;
	      pfx.fp_len = steer_pl->classify.l3.mask_width;
	      pfx.fp_addr.ip6 = steer_pl->classify.l3.prefix.ip6;

	      fib_table_entry_delete (fib_table_find
				      (FIB_PROTOCOL_IP6,
				       steer_pl->classify.l3.fib_table),
				      &pfx, FIB_SOURCE_SR);
	    }
	  else if (steer_pl->classify.traffic_type == SR_STEER_IPV4)
	    {
	      /* Remove FIB entry */
	      pfx.fp_proto = FIB_PROTOCOL_IP4;
	      pfx.fp_len = steer_pl->classify.l3.mask_width;
	      pfx.fp_addr.ip4 = steer_pl->classify.l3.prefix.ip4;

	      fib_table_entry_delete (fib_table_find
				      (FIB_PROTOCOL_IP4,
				       steer_pl->classify.l3.fib_table), &pfx,
				      FIB_SOURCE_SR);
	    }
	  else if (steer_pl->classify.traffic_type == SR_STEER_L2)
	    {
	      /* Remove HW redirection */
	      vnet_feature_enable_disable ("device-input",
					   "sr-policy-rewrite-encaps-l2",
					   sw_if_index, 0, 0, 0);
	      sm->sw_iface_sr_policies[sw_if_index] = ~(u32) 0;

	      /* Remove promiscous mode from interface */
	      vnet_main_t *vnm = vnet_get_main ();
	      ethernet_main_t *em = &ethernet_main;
	      ethernet_interface_t *eif =
		ethernet_get_interface (em, sw_if_index);

	      if (!eif)
		goto cleanup_error_redirection;

	      ethernet_set_flags (vnm, sw_if_index, 0);
	    }

	  /* Delete SR steering policy entry */
	  pool_put (sm->steer_policies, steer_pl);
	  mhash_unset (&sm->sr_steer_policies_hash, &key, NULL);

	  /* If no more SR policies or steering policies */
	  if (!pool_elts (sm->sr_policies) && !pool_elts (sm->steer_policies))
	    {
	      fib_table_unlock (sm->fib_table_ip6, FIB_PROTOCOL_IP6);
	      fib_table_unlock (sm->fib_table_ip4, FIB_PROTOCOL_IP6);
	      sm->fib_table_ip6 = (u32) ~ 0;
	      sm->fib_table_ip4 = (u32) ~ 0;
	    }

	  return 0;
	}
      else			/* It means user requested to update an existing SR steering policy */
	{
	  /* Retrieve SR steering policy */
	  if (bsid)
	    {
	      p = mhash_get (&sm->sr_policies_index_hash, bsid);
	      if (p)
		sr_policy = pool_elt_at_index (sm->sr_policies, p[0]);
	      else
		return -2;
	    }
	  else
	    sr_policy = pool_elt_at_index (sm->sr_policies, sr_policy_index);

	  if (!sr_policy)
	    return -2;

	  steer_pl->sr_policy = sr_policy - sm->sr_policies;

	  /* Remove old FIB/hw redirection and create a new one */
	  if (steer_pl->classify.traffic_type == SR_STEER_IPV6)
	    {
	      /* Remove FIB entry */
	      pfx.fp_proto = FIB_PROTOCOL_IP6;
	      pfx.fp_len = steer_pl->classify.l3.mask_width;
	      pfx.fp_addr.ip6 = steer_pl->classify.l3.prefix.ip6;

	      fib_table_entry_delete (fib_table_find
				      (FIB_PROTOCOL_IP6,
				       steer_pl->classify.l3.fib_table),
				      &pfx, FIB_SOURCE_SR);

	      /* Create a new one */
	      goto update_fib;
	    }
	  else if (steer_pl->classify.traffic_type == SR_STEER_IPV4)
	    {
	      /* Remove FIB entry */
	      pfx.fp_proto = FIB_PROTOCOL_IP4;
	      pfx.fp_len = steer_pl->classify.l3.mask_width;
	      pfx.fp_addr.ip4 = steer_pl->classify.l3.prefix.ip4;

	      fib_table_entry_delete (fib_table_find
				      (FIB_PROTOCOL_IP4,
				       steer_pl->classify.l3.fib_table),
				      &pfx, FIB_SOURCE_SR);

	      /* Create a new one */
	      goto update_fib;
	    }
	  else if (steer_pl->classify.traffic_type == SR_STEER_L2)
	    {
	      /* Update L2-HW redirection */
	      goto update_fib;
	    }
	}
    }
  else
    /* delete; steering policy does not exist; complain */
  if (is_del)
    return -4;

  /* Retrieve SR policy */
  if (bsid)
    {
      p = mhash_get (&sm->sr_policies_index_hash, bsid);
      if (p)
	sr_policy = pool_elt_at_index (sm->sr_policies, p[0]);
      else
	return -2;
    }
  else
    sr_policy = pool_elt_at_index (sm->sr_policies, sr_policy_index);

  /* Create a new steering policy */
  pool_get (sm->steer_policies, steer_pl);
  memset (steer_pl, 0, sizeof (*steer_pl));

  if (traffic_type == SR_STEER_IPV4 || traffic_type == SR_STEER_IPV6)
    {
      clib_memcpy (&steer_pl->classify.l3.prefix, prefix,
		   sizeof (ip46_address_t));
      steer_pl->classify.l3.mask_width = mask_width;
      steer_pl->classify.l3.fib_table =
	(table_id != (u32) ~ 0 ? table_id : 0);
      steer_pl->classify.traffic_type = traffic_type;
    }
  else if (traffic_type == SR_STEER_L2)
    {
      steer_pl->classify.l2.sw_if_index = sw_if_index;
      steer_pl->classify.traffic_type = traffic_type;
    }
  else
    {
      /* Incorrect API usage. Should never get here */
      pool_put (sm->steer_policies, steer_pl);
      mhash_unset (&sm->sr_steer_policies_hash, &key, NULL);
      return -1;
    }
  steer_pl->sr_policy = sr_policy - sm->sr_policies;

  /* Create and store key */
  mhash_set (&sm->sr_steer_policies_hash, &key, steer_pl - sm->steer_policies,
	     NULL);

  if (traffic_type == SR_STEER_L2)
    {
      if (!sr_policy->is_encap)
	goto cleanup_error_encap;

      if (vnet_feature_enable_disable
	  ("device-input", "sr-pl-rewrite-encaps-l2", sw_if_index, 1, 0, 0))
	goto cleanup_error_redirection;

      /* Set promiscous mode on interface */
      vnet_main_t *vnm = vnet_get_main ();
      ethernet_main_t *em = &ethernet_main;
      ethernet_interface_t *eif = ethernet_get_interface (em, sw_if_index);

      if (!eif)
	goto cleanup_error_redirection;

      ethernet_set_flags (vnm, sw_if_index,
			  ETHERNET_INTERFACE_FLAG_ACCEPT_ALL);
    }
  else if (traffic_type == SR_STEER_IPV4)
    if (!sr_policy->is_encap)
      goto cleanup_error_encap;

update_fib:
  /* FIB API calls - Recursive route through the BindingSID */
  if (traffic_type == SR_STEER_IPV6)
    {
      pfx.fp_proto = FIB_PROTOCOL_IP6;
      pfx.fp_len = steer_pl->classify.l3.mask_width;
      pfx.fp_addr.ip6 = steer_pl->classify.l3.prefix.ip6;

      fib_table_entry_path_add (fib_table_find (FIB_PROTOCOL_IP6,
						(table_id !=
						 (u32) ~ 0 ?
						 table_id : 0)),
				&pfx, FIB_SOURCE_SR,
				FIB_ENTRY_FLAG_LOOSE_URPF_EXEMPT,
				DPO_PROTO_IP6,
				(ip46_address_t *) & sr_policy->bsid, ~0,
				sm->fib_table_ip6, 1, NULL,
				FIB_ROUTE_PATH_FLAG_NONE);
    }
  else if (traffic_type == SR_STEER_IPV4)
    {
      pfx.fp_proto = FIB_PROTOCOL_IP4;
      pfx.fp_len = steer_pl->classify.l3.mask_width;
      pfx.fp_addr.ip4 = steer_pl->classify.l3.prefix.ip4;

      fib_table_entry_path_add (fib_table_find (FIB_PROTOCOL_IP4,
						(table_id !=
						 (u32) ~ 0 ?
						 table_id : 0)),
				&pfx, FIB_SOURCE_SR,
				FIB_ENTRY_FLAG_LOOSE_URPF_EXEMPT,
				DPO_PROTO_IP6,
				(ip46_address_t *) & sr_policy->bsid, ~0,
				sm->fib_table_ip4, 1, NULL,
				FIB_ROUTE_PATH_FLAG_NONE);
    }
  else if (traffic_type == SR_STEER_L2)
    {
      if (sw_if_index < vec_len (sm->sw_iface_sr_policies))
	sm->sw_iface_sr_policies[sw_if_index] = steer_pl->sr_policy;
      else
	{
	  vec_resize (sm->sw_iface_sr_policies,
		      (pool_len (sm->vnet_main->interface_main.sw_interfaces)
		       - vec_len (sm->sw_iface_sr_policies)));
	  sm->sw_iface_sr_policies[sw_if_index] = steer_pl->sr_policy;
	}
    }

  return 0;

cleanup_error_encap:
  pool_put (sm->steer_policies, steer_pl);
  mhash_unset (&sm->sr_steer_policies_hash, &key, NULL);
  return -5;

cleanup_error_redirection:
  pool_put (sm->steer_policies, steer_pl);
  mhash_unset (&sm->sr_steer_policies_hash, &key, NULL);
  return -3;
}

static clib_error_t *
sr_steer_policy_command_fn (vlib_main_t * vm, unformat_input_t * input,
			    vlib_cli_command_t * cmd)
{
  vnet_main_t *vnm = vnet_get_main ();

  int is_del = 0;

  ip46_address_t prefix;
  u32 dst_mask_width = 0;
  u32 sw_if_index = (u32) ~ 0;
  u8 traffic_type = 0;
  u32 fib_table = (u32) ~ 0;

  ip6_address_t bsid;
  u32 sr_policy_index = (u32) ~ 0;

  u8 sr_policy_set = 0;

  memset (&prefix, 0, sizeof (ip46_address_t));

  int rv;
  while (unformat_check_input (input) != UNFORMAT_END_OF_INPUT)
    {
      if (unformat (input, "del"))
	is_del = 1;
      else if (!traffic_type
	       && unformat (input, "l3 %U/%d", unformat_ip6_address,
			    &prefix.ip6, &dst_mask_width))
	traffic_type = SR_STEER_IPV6;
      else if (!traffic_type
	       && unformat (input, "l3 %U/%d", unformat_ip4_address,
			    &prefix.ip4, &dst_mask_width))
	traffic_type = SR_STEER_IPV4;
      else if (!traffic_type
	       && unformat (input, "l2 %U", unformat_vnet_sw_interface, vnm,
			    &sw_if_index))
	traffic_type = SR_STEER_L2;
      else if (!sr_policy_set
	       && unformat (input, "via sr policy index %d",
			    &sr_policy_index))
	sr_policy_set = 1;
      else if (!sr_policy_set
	       && unformat (input, "via sr policy bsid %U",
			    unformat_ip6_address, &bsid))
	sr_policy_set = 1;
      else if (fib_table == (u32) ~ 0
	       && unformat (input, "fib-table %d", &fib_table));
      else
	break;
    }

  if (!traffic_type)
    return clib_error_return (0, "No L2/L3 traffic specified");
  if (!sr_policy_set)
    return clib_error_return (0, "No SR policy specified");

  /* Make sure that the prefixes are clean */
  if (traffic_type == SR_STEER_IPV4)
    {
      u32 mask =
	(dst_mask_width ? (0xFFFFFFFFu >> (32 - dst_mask_width)) : 0);
      prefix.ip4.as_u32 &= mask;
    }
  else if (traffic_type == SR_STEER_IPV6)
    {
      ip6_address_t mask;
      ip6_address_mask_from_width (&mask, dst_mask_width);
      ip6_address_mask (&prefix.ip6, &mask);
    }

  rv =
    sr_steering_policy (is_del, (sr_policy_index == ~(u32) 0 ? &bsid : NULL),
			sr_policy_index, fib_table, &prefix, dst_mask_width,
			sw_if_index, traffic_type);

  switch (rv)
    {
    case 0:
      break;
    case 1:
      return 0;
    case -1:
      return clib_error_return (0, "Incorrect API usage.");
    case -2:
      return clib_error_return (0,
				"The requested SR policy could not be located. Review the BSID/index.");
    case -3:
      return clib_error_return (0,
				"Unable to do SW redirect. Incorrect interface.");
    case -4:
      return clib_error_return (0,
				"The requested SR steering policy could not be deleted.");
    case -5:
      return clib_error_return (0,
				"The SR policy is not an encapsulation one.");
    default:
      return clib_error_return (0, "BUG: sr steer policy returns %d", rv);
    }
  return 0;
}

/* *INDENT-OFF* */
VLIB_CLI_COMMAND (sr_steer_policy_command, static) = {
  .path = "sr steer",
  .short_help = "sr steer (del) [l3 <ip_addr/mask>|l2 <sf_if>]"
    "via sr policy [index <sr_policy_index>|bsid <bsid_ip6_addr>]"
    "(fib-table <fib_table_index>)",
  .long_help =
    "\tSteer a L2 or L3 traffic through an existing SR policy.\n"
    "\tExamples:\n"
    "\t\tsr steer l3 2001::/64 via sr_policy index 5\n"
    "\t\tsr steer l3 2001::/64 via sr_policy bsid 2010::9999:1\n"
    "\t\tsr steer l2 GigabitEthernet0/5/0 via sr_policy index 5\n"
    "\t\tsr steer del l3 2001::/64 via sr_policy index 5\n",
  .function = sr_steer_policy_command_fn,
};
/* *INDENT-ON* */

static clib_error_t *
show_sr_steering_policies_command_fn (vlib_main_t * vm,
				      unformat_input_t * input,
				      vlib_cli_command_t * cmd)
{
  ip6_sr_main_t *sm = &sr_main;
  ip6_sr_steering_policy_t **steer_policies = 0;
  ip6_sr_steering_policy_t *steer_pl;

  vnet_main_t *vnm = vnet_get_main ();

  ip6_sr_policy_t *pl = 0;
  int i;

  vlib_cli_output (vm, "SR steering policies:");
  /* *INDENT-OFF* */
  pool_foreach (steer_pl, sm->steer_policies, ({vec_add1(steer_policies, steer_pl);}));
  /* *INDENT-ON* */
  vlib_cli_output (vm, "Traffic\t\tSR policy BSID");
  for (i = 0; i < vec_len (steer_policies); i++)
    {
      steer_pl = steer_policies[i];
      pl = pool_elt_at_index (sm->sr_policies, steer_pl->sr_policy);
      if (steer_pl->classify.traffic_type == SR_STEER_L2)
	{
	  vlib_cli_output (vm, "L2 %U\t%U",
			   format_vnet_sw_if_index_name, vnm,
			   steer_pl->classify.l2.sw_if_index,
			   format_ip6_address, &pl->bsid);
	}
      else if (steer_pl->classify.traffic_type == SR_STEER_IPV4)
	{
	  vlib_cli_output (vm, "L3 %U/%d\t%U",
			   format_ip4_address,
			   &steer_pl->classify.l3.prefix.ip4,
			   steer_pl->classify.l3.mask_width,
			   format_ip6_address, &pl->bsid);
	}
      else if (steer_pl->classify.traffic_type == SR_STEER_IPV6)
	{
	  vlib_cli_output (vm, "L3 %U/%d\t%U",
			   format_ip6_address,
			   &steer_pl->classify.l3.prefix.ip6,
			   steer_pl->classify.l3.mask_width,
			   format_ip6_address, &pl->bsid);
	}
    }
  return 0;
}

/* *INDENT-OFF* */
VLIB_CLI_COMMAND (show_sr_steering_policies_command, static) = {
  .path = "show sr steering policies",
  .short_help = "show sr steering policies",
  .function = show_sr_steering_policies_command_fn,
};
/* *INDENT-ON* */

clib_error_t *
sr_steering_init (vlib_main_t * vm)
{
  ip6_sr_main_t *sm = &sr_main;

  /* Init memory for function keys */
  mhash_init (&sm->sr_steer_policies_hash, sizeof (uword),
	      sizeof (sr_steering_key_t));

  sm->sw_iface_sr_policies = 0;

  sm->vnet_main = vnet_get_main ();

  return 0;
}

/* *INDENT-OFF* */
VLIB_INIT_FUNCTION (sr_steering_init);
/* *INDENT-ON* */

/* *INDENT-OFF* */
VNET_FEATURE_INIT (sr_pl_rewrite_encaps_l2, static) =
{
  .arc_name = "device-input",
  .node_name = "sr-pl-rewrite-encaps-l2",
  .runs_before = VNET_FEATURES ("ethernet-input"),
};
/* *INDENT-ON* */

/*
* fd.io coding-style-patch-verification: ON
*
* Local Variables:
* eval: (c-set-style "gnu")
* End:
*/