aboutsummaryrefslogtreecommitdiffstats
path: root/src/plugins/wireguard/wireguard_output_tun.c
blob: 4d85a5912d68059cb8a4c0c26e334dce24bf9007 (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
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
/*
 * Copyright (c) 2020 Doc.ai and/or its affiliates.
 * Copyright (c) 2020 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.
 */

#include <vlib/vlib.h>
#include <vnet/vnet.h>
#include <vppinfra/error.h>

#include <wireguard/wireguard.h>
#include <wireguard/wireguard_send.h>

#define foreach_wg_output_error                                               \
  _ (NONE, "No error")                                                        \
  _ (PEER, "Peer error")                                                      \
  _ (KEYPAIR, "Keypair error")                                                \
  _ (TOO_BIG, "packet too big")                                               \
  _ (CRYPTO_ENGINE_ERROR, "crypto engine error (packet dropped)")

typedef enum
{
#define _(sym,str) WG_OUTPUT_ERROR_##sym,
  foreach_wg_output_error
#undef _
    WG_OUTPUT_N_ERROR,
} wg_output_error_t;

static char *wg_output_error_strings[] = {
#define _(sym,string) string,
  foreach_wg_output_error
#undef _
};

typedef enum
{
  WG_OUTPUT_NEXT_ERROR,
  WG_OUTPUT_NEXT_HANDOFF,
  WG_OUTPUT_NEXT_INTERFACE_OUTPUT,
  WG_OUTPUT_N_NEXT,
} wg_output_next_t;

typedef struct
{
  index_t peer;
  u8 header[sizeof (ip6_udp_header_t)];
  u8 is_ip4;
} wg_output_tun_trace_t;

typedef struct
{
  index_t peer;
  u32 next_index;
} wg_output_tun_post_trace_t;

u8 *
format_ip4_udp_header (u8 * s, va_list * args)
{
  ip4_udp_header_t *hdr4 = va_arg (*args, ip4_udp_header_t *);

  s = format (s, "%U:$U", format_ip4_header, &hdr4->ip4, format_udp_header,
	      &hdr4->udp);
  return (s);
}

u8 *
format_ip6_udp_header (u8 *s, va_list *args)
{
  ip6_udp_header_t *hdr6 = va_arg (*args, ip6_udp_header_t *);

  s = format (s, "%U:$U", format_ip6_header, &hdr6->ip6, format_udp_header,
	      &hdr6->udp);
  return (s);
}

/* packet trace format function */
static u8 *
format_wg_output_tun_trace (u8 * s, va_list * args)
{
  CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
  CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);

  wg_output_tun_trace_t *t = va_arg (*args, wg_output_tun_trace_t *);

  s = format (s, "peer: %d\n", t->peer);
  s = format (s, "  Encrypted packet: ");

  s = t->is_ip4 ? format (s, "%U", format_ip4_udp_header, t->header) :
		  format (s, "%U", format_ip6_udp_header, t->header);
  return s;
}

/* post node - packet trace format function */
static u8 *
format_wg_output_tun_post_trace (u8 *s, va_list *args)
{
  CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
  CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);

  wg_output_tun_post_trace_t *t = va_arg (*args, wg_output_tun_post_trace_t *);

  s = format (s, "peer: %d\n", t->peer);
  s = format (s, "  wg-post: next node index %u", t->next_index);
  return s;
}

static_always_inline void
wg_prepare_sync_enc_op (vlib_main_t *vm, vnet_crypto_op_t **crypto_ops,
			u8 *src, u32 src_len, u8 *dst, u8 *aad, u32 aad_len,
			u64 nonce, vnet_crypto_key_index_t key_index, u32 bi,
			u8 *iv)
{
  vnet_crypto_op_t _op, *op = &_op;
  u8 src_[] = {};

  clib_memset (iv, 0, 4);
  clib_memcpy (iv + 4, &nonce, sizeof (nonce));

  vec_add2_aligned (crypto_ops[0], op, 1, CLIB_CACHE_LINE_BYTES);
  vnet_crypto_op_init (op, VNET_CRYPTO_OP_CHACHA20_POLY1305_ENC);

  op->tag_len = NOISE_AUTHTAG_LEN;
  op->tag = dst + src_len;
  op->src = !src ? src_ : src;
  op->len = src_len;
  op->dst = dst;
  op->key_index = key_index;
  op->aad = aad;
  op->aad_len = aad_len;
  op->iv = iv;
  op->user_data = bi;
}

static_always_inline void
wg_output_process_ops (vlib_main_t *vm, vlib_node_runtime_t *node,
		       vnet_crypto_op_t *ops, vlib_buffer_t *b[], u16 *nexts,
		       u16 drop_next)
{
  u32 n_fail, n_ops = vec_len (ops);
  vnet_crypto_op_t *op = ops;

  if (n_ops == 0)
    return;

  n_fail = n_ops - vnet_crypto_process_ops (vm, op, n_ops);

  while (n_fail)
    {
      ASSERT (op - ops < n_ops);

      if (op->status != VNET_CRYPTO_OP_STATUS_COMPLETED)
	{
	  u32 bi = op->user_data;
	  b[bi]->error = node->errors[WG_OUTPUT_ERROR_CRYPTO_ENGINE_ERROR];
	  nexts[bi] = drop_next;
	  n_fail--;
	}
      op++;
    }
}

static_always_inline void
wg_output_tun_add_to_frame (vlib_main_t *vm, vnet_crypto_async_frame_t *f,
			    u32 key_index, u32 crypto_len,
			    i16 crypto_start_offset, u32 buffer_index,
			    u16 next_node, u8 *iv, u8 *tag, u8 flags)
{
  vnet_crypto_async_frame_elt_t *fe;
  u16 index;

  ASSERT (f->n_elts < VNET_CRYPTO_FRAME_SIZE);

  index = f->n_elts;
  fe = &f->elts[index];
  f->n_elts++;
  fe->key_index = key_index;
  fe->crypto_total_length = crypto_len;
  fe->crypto_start_offset = crypto_start_offset;
  fe->iv = iv;
  fe->tag = tag;
  fe->flags = flags;
  f->buffer_indices[index] = buffer_index;
  f->next_node_index[index] = next_node;
}

static_always_inline enum noise_state_crypt
wq_output_tun_process (vlib_main_t *vm, vnet_crypto_op_t **crypto_ops,
		       noise_remote_t *r, uint32_t *r_idx, uint64_t *nonce,
		       uint8_t *src, size_t srclen, uint8_t *dst, u32 bi,
		       u8 *iv, f64 time)
{
  noise_keypair_t *kp;
  enum noise_state_crypt ret = SC_FAILED;

  if ((kp = r->r_current) == NULL)
    goto error;

  /* We confirm that our values are within our tolerances. We want:
   *  - a valid keypair
   *  - our keypair to be less than REJECT_AFTER_TIME seconds old
   *  - our receive counter to be less than REJECT_AFTER_MESSAGES
   *  - our send counter to be less than REJECT_AFTER_MESSAGES
   */
  if (!kp->kp_valid ||
      wg_birthdate_has_expired_opt (kp->kp_birthdate, REJECT_AFTER_TIME,
				    time) ||
      kp->kp_ctr.c_recv >= REJECT_AFTER_MESSAGES ||
      ((*nonce = noise_counter_send (&kp->kp_ctr)) > REJECT_AFTER_MESSAGES))
    goto error;

  /* We encrypt into the same buffer, so the caller must ensure that buf
   * has NOISE_AUTHTAG_LEN bytes to store the MAC. The nonce and index
   * are passed back out to the caller through the provided data pointer. */
  *r_idx = kp->kp_remote_index;

  wg_prepare_sync_enc_op (vm, crypto_ops, src, srclen, dst, NULL, 0, *nonce,
			  kp->kp_send_index, bi, iv);

  /* If our values are still within tolerances, but we are approaching
   * the tolerances, we notify the caller with ESTALE that they should
   * establish a new keypair. The current keypair can continue to be used
   * until the tolerances are hit. We notify if:
   *  - our send counter is valid and not less than REKEY_AFTER_MESSAGES
   *  - we're the initiator and our keypair is older than
   *    REKEY_AFTER_TIME seconds */
  ret = SC_KEEP_KEY_FRESH;
  if ((kp->kp_valid && *nonce >= REKEY_AFTER_MESSAGES) ||
      (kp->kp_is_initiator && wg_birthdate_has_expired_opt (
				kp->kp_birthdate, REKEY_AFTER_TIME, time)))
    goto error;

  ret = SC_OK;
error:
  return ret;
}

static_always_inline enum noise_state_crypt
wg_add_to_async_frame (vlib_main_t *vm, wg_per_thread_data_t *ptd,
		       vnet_crypto_async_frame_t **async_frame,
		       vlib_buffer_t *b, u8 *payload, u32 payload_len, u32 bi,
		       u16 next, u16 async_next, noise_remote_t *r,
		       uint32_t *r_idx, uint64_t *nonce, u8 *iv, f64 time)
{
  wg_post_data_t *post = wg_post_data (b);
  u8 flag = 0;
  noise_keypair_t *kp;

  post->next_index = next;

  /* crypto */
  enum noise_state_crypt ret = SC_FAILED;

  if ((kp = r->r_current) == NULL)
    goto error;

  /* We confirm that our values are within our tolerances. We want:
   *  - a valid keypair
   *  - our keypair to be less than REJECT_AFTER_TIME seconds old
   *  - our receive counter to be less than REJECT_AFTER_MESSAGES
   *  - our send counter to be less than REJECT_AFTER_MESSAGES
   */
  if (!kp->kp_valid ||
      wg_birthdate_has_expired_opt (kp->kp_birthdate, REJECT_AFTER_TIME,
				    time) ||
      kp->kp_ctr.c_recv >= REJECT_AFTER_MESSAGES ||
      ((*nonce = noise_counter_send (&kp->kp_ctr)) > REJECT_AFTER_MESSAGES))
    goto error;

  /* We encrypt into the same buffer, so the caller must ensure that buf
   * has NOISE_AUTHTAG_LEN bytes to store the MAC. The nonce and index
   * are passed back out to the caller through the provided data pointer. */
  *r_idx = kp->kp_remote_index;

  clib_memset (iv, 0, 4);
  clib_memcpy (iv + 4, nonce, sizeof (*nonce));

  /* get a frame for this op if we don't yet have one or it's full  */
  if (NULL == *async_frame || vnet_crypto_async_frame_is_full (*async_frame))
    {
      *async_frame = vnet_crypto_async_get_frame (
	vm, VNET_CRYPTO_OP_CHACHA20_POLY1305_TAG16_AAD0_ENC);
      /* Save the frame to the list we'll submit at the end */
      vec_add1 (ptd->async_frames, *async_frame);
    }

  /* this always succeeds because we know the frame is not full */
  wg_output_tun_add_to_frame (vm, *async_frame, kp->kp_send_index, payload_len,
			      payload - b->data, bi, async_next, iv,
			      payload + payload_len, flag);

  /* If our values are still within tolerances, but we are approaching
   * the tolerances, we notify the caller with ESTALE that they should
   * establish a new keypair. The current keypair can continue to be used
   * until the tolerances are hit. We notify if:
   *  - our send counter is valid and not less than REKEY_AFTER_MESSAGES
   *  - we're the initiator and our keypair is older than
   *    REKEY_AFTER_TIME seconds */
  ret = SC_KEEP_KEY_FRESH;
  if ((kp->kp_valid && *nonce >= REKEY_AFTER_MESSAGES) ||
      (kp->kp_is_initiator && wg_birthdate_has_expired_opt (
				kp->kp_birthdate, REKEY_AFTER_TIME, time)))
    goto error;

  ret = SC_OK;
error:
  return ret;
}

static_always_inline void
wg_calc_checksum (vlib_main_t *vm, vlib_buffer_t *b)
{
  int bogus = 0;
  u8 ip_ver_out = (*((u8 *) vlib_buffer_get_current (b)) >> 4);

  /* IPv6 UDP checksum is mandatory */
  if (ip_ver_out == 6)
    {
      ip6_header_t *ip6 =
	(ip6_header_t *) ((u8 *) vlib_buffer_get_current (b));
      udp_header_t *udp = ip6_next_header (ip6);
      udp->checksum = ip6_tcp_udp_icmp_compute_checksum (vm, b, ip6, &bogus);
    }
}

/* is_ip4 - inner header flag */
always_inline uword
wg_output_tun_inline (vlib_main_t *vm, vlib_node_runtime_t *node,
		      vlib_frame_t *frame, u8 is_ip4, u16 async_next_node)
{
  wg_main_t *wmp = &wg_main;
  wg_per_thread_data_t *ptd =
    vec_elt_at_index (wmp->per_thread_data, vm->thread_index);
  u32 *from = vlib_frame_vector_args (frame);
  u32 n_left_from = frame->n_vectors;
  ip4_udp_wg_header_t *hdr4_out = NULL;
  ip6_udp_wg_header_t *hdr6_out = NULL;
  message_data_t *message_data_wg = NULL;
  vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b = bufs;
  vnet_crypto_op_t **crypto_ops = &ptd->crypto_ops;
  u16 nexts[VLIB_FRAME_SIZE], *next = nexts;
  vlib_buffer_t *sync_bufs[VLIB_FRAME_SIZE];
  u32 thread_index = vm->thread_index;
  u16 n_sync = 0;
  const u16 drop_next = WG_OUTPUT_NEXT_ERROR;
  const u8 is_async = wg_op_mode_is_set_ASYNC ();
  vnet_crypto_async_frame_t *async_frame = NULL;
  u16 n_async = 0;
  u16 noop_nexts[VLIB_FRAME_SIZE], *noop_next = noop_nexts, n_noop = 0;
  u16 err = !0;
  u32 sync_bi[VLIB_FRAME_SIZE];
  u32 noop_bi[VLIB_FRAME_SIZE];

  vlib_get_buffers (vm, from, bufs, n_left_from);
  vec_reset_length (ptd->crypto_ops);
  vec_reset_length (ptd->async_frames);

  wg_peer_t *peer = NULL;
  u32 adj_index = 0;
  u32 last_adj_index = ~0;
  index_t peeri = INDEX_INVALID;

  f64 time = clib_time_now (&vm->clib_time) + vm->time_offset;

  while (n_left_from > 0)
    {
      u8 iph_offset = 0;
      u8 is_ip4_out = 1;
      u8 *plain_data;
      u16 plain_data_len;

      if (n_left_from > 2)
	{
	  u8 *p;
	  vlib_prefetch_buffer_header (b[2], LOAD);
	  p = vlib_buffer_get_current (b[1]);
	  CLIB_PREFETCH (p, CLIB_CACHE_LINE_BYTES, LOAD);
	  CLIB_PREFETCH (vlib_buffer_get_tail (b[1]), CLIB_CACHE_LINE_BYTES,
			 LOAD);
	}

      noop_next[0] = WG_OUTPUT_NEXT_ERROR;
      err = WG_OUTPUT_NEXT_ERROR;

      adj_index = vnet_buffer (b[0])->ip.adj_index[VLIB_TX];

      if (PREDICT_FALSE (last_adj_index != adj_index))
	{
	  peeri = wg_peer_get_by_adj_index (adj_index);
	  if (peeri == INDEX_INVALID)
	    {
	      b[0]->error = node->errors[WG_OUTPUT_ERROR_PEER];
	      goto out;
	    }
	  peer = wg_peer_get (peeri);
	}

      if (!peer || wg_peer_is_dead (peer))
	{
	  b[0]->error = node->errors[WG_OUTPUT_ERROR_PEER];
	  goto out;
	}
      if (PREDICT_FALSE (~0 == peer->output_thread_index))
	{
	  /* this is the first packet to use this peer, claim the peer
	   * for this thread.
	   */
	  clib_atomic_cmp_and_swap (&peer->output_thread_index, ~0,
				    wg_peer_assign_thread (thread_index));
	}

      if (PREDICT_FALSE (thread_index != peer->output_thread_index))
	{
	  noop_next[0] = WG_OUTPUT_NEXT_HANDOFF;
	  err = WG_OUTPUT_NEXT_HANDOFF;
	  goto next;
	}

      if (PREDICT_FALSE (!peer->remote.r_current))
	{
	  wg_send_handshake_from_mt (peeri, false);
	  b[0]->error = node->errors[WG_OUTPUT_ERROR_KEYPAIR];
	  goto out;
	}

      iph_offset = vnet_buffer (b[0])->ip.save_rewrite_length;
      plain_data_len = vlib_buffer_length_in_chain (vm, b[0]) - iph_offset;
      u8 *iv_data = b[0]->pre_data;

      size_t encrypted_packet_len = message_data_len (plain_data_len);

      /*
       * Ensure there is enough space to write the encrypted data
       * into the packet
       */
      if (PREDICT_FALSE (encrypted_packet_len >= WG_DEFAULT_DATA_SIZE) ||
	  PREDICT_FALSE ((iph_offset + encrypted_packet_len) >=
			 vlib_buffer_get_default_data_size (vm)))
	{
	  b[0]->error = node->errors[WG_OUTPUT_ERROR_TOO_BIG];
	  goto out;
	}

      /*
       * Move the buffer to fit ethernet header
       */
      if (b[0]->current_data + VLIB_BUFFER_PRE_DATA_SIZE <
	  sizeof (ethernet_header_t))
	{
	  vlib_buffer_move (vm, b[0], 0);
	}

      plain_data = vlib_buffer_get_current (b[0]) + iph_offset;

      is_ip4_out = ip46_address_is_ip4 (&peer->src.addr);
      if (is_ip4_out)
	{
	  hdr4_out = vlib_buffer_get_current (b[0]);
	  message_data_wg = &hdr4_out->wg;
	}
      else
	{
	  hdr6_out = vlib_buffer_get_current (b[0]);
	  message_data_wg = &hdr6_out->wg;
	}

      if (PREDICT_FALSE (last_adj_index != adj_index))
	{
	  wg_timers_any_authenticated_packet_sent_opt (peer, time);
	  wg_timers_data_sent_opt (peer, time);
	  wg_timers_any_authenticated_packet_traversal (peer);
	  last_adj_index = adj_index;
	}

      /* Here we are sure that can send packet to next node */
      next[0] = WG_OUTPUT_NEXT_INTERFACE_OUTPUT;

      enum noise_state_crypt state;

      if (is_async)
	{
	  state = wg_add_to_async_frame (
	    vm, ptd, &async_frame, b[0], plain_data, plain_data_len,
	    from[b - bufs], next[0], async_next_node, &peer->remote,
	    &message_data_wg->receiver_index, &message_data_wg->counter,
	    iv_data, time);
	}
      else
	{
	  state = wq_output_tun_process (
	    vm, crypto_ops, &peer->remote, &message_data_wg->receiver_index,
	    &message_data_wg->counter, plain_data, plain_data_len, plain_data,
	    n_sync, iv_data, time);
	}

      if (PREDICT_FALSE (state == SC_KEEP_KEY_FRESH))
	{
	  wg_send_handshake_from_mt (peeri, false);
	}
      else if (PREDICT_FALSE (state == SC_FAILED))
	{
	  // TODO: Maybe wrong
	  wg_send_handshake_from_mt (peeri, false);
	  wg_peer_update_flags (peeri, WG_PEER_ESTABLISHED, false);
	  noop_next[0] = WG_OUTPUT_NEXT_ERROR;
	  goto out;
	}

      err = WG_OUTPUT_NEXT_INTERFACE_OUTPUT;

      if (is_ip4_out)
	{
	  hdr4_out->wg.header.type = MESSAGE_DATA;
	  hdr4_out->udp.length = clib_host_to_net_u16 (encrypted_packet_len +
						       sizeof (udp_header_t));
	  b[0]->current_length =
	    (encrypted_packet_len + sizeof (ip4_udp_header_t));
	  ip4_header_set_len_w_chksum (
	    &hdr4_out->ip4, clib_host_to_net_u16 (b[0]->current_length));
	}
      else
	{
	  hdr6_out->wg.header.type = MESSAGE_DATA;
	  hdr6_out->ip6.payload_length = hdr6_out->udp.length =
	    clib_host_to_net_u16 (encrypted_packet_len +
				  sizeof (udp_header_t));
	  b[0]->current_length =
	    (encrypted_packet_len + sizeof (ip6_udp_header_t));
	}

    out:
      if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
			 && (b[0]->flags & VLIB_BUFFER_IS_TRACED)))
	{
	  wg_output_tun_trace_t *t =
	    vlib_add_trace (vm, node, b[0], sizeof (*t));

	  t->peer = peeri;
	  t->is_ip4 = is_ip4_out;
	  if (hdr4_out)
	    clib_memcpy (t->header, hdr4_out, sizeof (ip4_udp_header_t));
	  else if (hdr6_out)
	    clib_memcpy (t->header, hdr6_out, sizeof (ip6_udp_header_t));
	}

    next:
      if (PREDICT_FALSE (err != WG_OUTPUT_NEXT_INTERFACE_OUTPUT))
	{
	  noop_bi[n_noop] = from[b - bufs];
	  n_noop++;
	  noop_next++;
	  goto next_left;
	}
      if (!is_async)
	{
	  sync_bi[n_sync] = from[b - bufs];
	  sync_bufs[n_sync] = b[0];
	  n_sync += 1;
	  next += 1;
	}
      else
	{
	  n_async++;
	}
    next_left:
      n_left_from -= 1;
      b += 1;
    }

  if (n_sync)
    {
      /* wg-output-process-ops */
      wg_output_process_ops (vm, node, ptd->crypto_ops, sync_bufs, nexts,
			     drop_next);

      int n_left_from_sync_bufs = n_sync;
      while (n_left_from_sync_bufs > 0)
	{
	  n_left_from_sync_bufs--;
	  wg_calc_checksum (vm, sync_bufs[n_left_from_sync_bufs]);
	}

      vlib_buffer_enqueue_to_next (vm, node, sync_bi, nexts, n_sync);
    }
  if (n_async)
    {
      /* submit all of the open frames */
      vnet_crypto_async_frame_t **async_frame;

      vec_foreach (async_frame, ptd->async_frames)
	{
	  if (PREDICT_FALSE (
		vnet_crypto_async_submit_open_frame (vm, *async_frame) < 0))
	    {
	      u32 n_drop = (*async_frame)->n_elts;
	      u32 *bi = (*async_frame)->buffer_indices;
	      u16 index = n_noop;
	      while (n_drop--)
		{
		  noop_bi[index] = bi[0];
		  vlib_buffer_t *b = vlib_get_buffer (vm, bi[0]);
		  noop_nexts[index] = drop_next;
		  b->error = node->errors[WG_OUTPUT_ERROR_CRYPTO_ENGINE_ERROR];
		  bi++;
		  index++;
		}
	      n_noop += (*async_frame)->n_elts;

	      vnet_crypto_async_reset_frame (*async_frame);
	      vnet_crypto_async_free_frame (vm, *async_frame);
	    }
	}
    }
  if (n_noop)
    {
      vlib_buffer_enqueue_to_next (vm, node, noop_bi, noop_nexts, n_noop);
    }

  return frame->n_vectors;
}

always_inline uword
wg_output_tun_post (vlib_main_t *vm, vlib_node_runtime_t *node,
		    vlib_frame_t *frame)
{
  vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b = bufs;
  u16 nexts[VLIB_FRAME_SIZE], *next = nexts;
  u32 *from = vlib_frame_vector_args (frame);
  u32 n_left = frame->n_vectors;

  index_t peeri = ~0;

  vlib_get_buffers (vm, from, b, n_left);

  if (n_left >= 4)
    {
      vlib_prefetch_buffer_header (b[0], LOAD);
      vlib_prefetch_buffer_header (b[1], LOAD);
      vlib_prefetch_buffer_header (b[2], LOAD);
      vlib_prefetch_buffer_header (b[3], LOAD);
    }

  while (n_left > 8)
    {
      vlib_prefetch_buffer_header (b[4], LOAD);
      vlib_prefetch_buffer_header (b[5], LOAD);
      vlib_prefetch_buffer_header (b[6], LOAD);
      vlib_prefetch_buffer_header (b[7], LOAD);

      next[0] = (wg_post_data (b[0]))->next_index;
      next[1] = (wg_post_data (b[1]))->next_index;
      next[2] = (wg_post_data (b[2]))->next_index;
      next[3] = (wg_post_data (b[3]))->next_index;

      wg_calc_checksum (vm, b[0]);
      wg_calc_checksum (vm, b[1]);
      wg_calc_checksum (vm, b[2]);
      wg_calc_checksum (vm, b[3]);

      if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE))
	{
	  if (b[0]->flags & VLIB_BUFFER_IS_TRACED)
	    {
	      wg_output_tun_post_trace_t *tr =
		vlib_add_trace (vm, node, b[0], sizeof (*tr));
	      peeri = wg_peer_get_by_adj_index (
		vnet_buffer (b[0])->ip.adj_index[VLIB_TX]);
	      tr->peer = peeri;
	      tr->next_index = next[0];
	    }
	  if (b[1]->flags & VLIB_BUFFER_IS_TRACED)
	    {
	      wg_output_tun_post_trace_t *tr =
		vlib_add_trace (vm, node, b[1], sizeof (*tr));
	      peeri = wg_peer_get_by_adj_index (
		vnet_buffer (b[1])->ip.adj_index[VLIB_TX]);
	      tr->next_index = next[1];
	    }
	  if (b[2]->flags & VLIB_BUFFER_IS_TRACED)
	    {
	      wg_output_tun_post_trace_t *tr =
		vlib_add_trace (vm, node, b[2], sizeof (*tr));
	      peeri = wg_peer_get_by_adj_index (
		vnet_buffer (b[2])->ip.adj_index[VLIB_TX]);
	      tr->next_index = next[2];
	    }
	  if (b[3]->flags & VLIB_BUFFER_IS_TRACED)
	    {
	      wg_output_tun_post_trace_t *tr =
		vlib_add_trace (vm, node, b[3], sizeof (*tr));
	      peeri = wg_peer_get_by_adj_index (
		vnet_buffer (b[3])->ip.adj_index[VLIB_TX]);
	      tr->next_index = next[3];
	    }
	}

      b += 4;
      next += 4;
      n_left -= 4;
    }

  while (n_left > 0)
    {
      wg_calc_checksum (vm, b[0]);

      next[0] = (wg_post_data (b[0]))->next_index;
      if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE) &&
			 (b[0]->flags & VLIB_BUFFER_IS_TRACED)))
	{
	  wg_output_tun_post_trace_t *tr =
	    vlib_add_trace (vm, node, b[0], sizeof (*tr));
	  peeri = wg_peer_get_by_adj_index (
	    vnet_buffer (b[0])->ip.adj_index[VLIB_TX]);
	  tr->next_index = next[0];
	}

      b += 1;
      next += 1;
      n_left -= 1;
    }

  vlib_buffer_enqueue_to_next (vm, node, from, nexts, frame->n_vectors);
  return frame->n_vectors;
}

VLIB_REGISTER_NODE (wg4_output_tun_post_node) = {
  .name = "wg4-output-tun-post-node",
  .vector_size = sizeof (u32),
  .format_trace = format_wg_output_tun_post_trace,
  .type = VLIB_NODE_TYPE_INTERNAL,
  .sibling_of = "wg4-output-tun",
  .n_errors = ARRAY_LEN (wg_output_error_strings),
  .error_strings = wg_output_error_strings,
};

VLIB_REGISTER_NODE (wg6_output_tun_post_node) = {
  .name = "wg6-output-tun-post-node",
  .vector_size = sizeof (u32),
  .format_trace = format_wg_output_tun_post_trace,
  .type = VLIB_NODE_TYPE_INTERNAL,
  .sibling_of = "wg6-output-tun",
  .n_errors = ARRAY_LEN (wg_output_error_strings),
  .error_strings = wg_output_error_strings,
};

VLIB_NODE_FN (wg4_output_tun_post_node)
(vlib_main_t *vm, vlib_node_runtime_t *node, vlib_frame_t *from_frame)
{
  return wg_output_tun_post (vm, node, from_frame);
}

VLIB_NODE_FN (wg6_output_tun_post_node)
(vlib_main_t *vm, vlib_node_runtime_t *node, vlib_frame_t *from_frame)
{
  return wg_output_tun_post (vm, node, from_frame);
}

VLIB_NODE_FN (wg4_output_tun_node)
(vlib_main_t *vm, vlib_node_runtime_t *node, vlib_frame_t *frame)
{
  return wg_output_tun_inline (vm, node, frame, /* is_ip4 */ 1,
			       wg_encrypt_async_next.wg4_post_next);
}

VLIB_NODE_FN (wg6_output_tun_node)
(vlib_main_t *vm, vlib_node_runtime_t *node, vlib_frame_t *frame)
{
  return wg_output_tun_inline (vm, node, frame, /* is_ip4 */ 0,
			       wg_encrypt_async_next.wg6_post_next);
}

/* *INDENT-OFF* */
VLIB_REGISTER_NODE (wg4_output_tun_node) =
{
  .name = "wg4-output-tun",
  .vector_size = sizeof (u32),
  .format_trace = format_wg_output_tun_trace,
  .type = VLIB_NODE_TYPE_INTERNAL,
  .n_errors = ARRAY_LEN (wg_output_error_strings),
  .error_strings = wg_output_error_strings,
  .n_next_nodes = WG_OUTPUT_N_NEXT,
  .next_nodes = {
        [WG_OUTPUT_NEXT_HANDOFF] = "wg4-output-tun-handoff",
        [WG_OUTPUT_NEXT_INTERFACE_OUTPUT] = "adj-midchain-tx",
        [WG_OUTPUT_NEXT_ERROR] = "error-drop",
  },
};

VLIB_REGISTER_NODE (wg6_output_tun_node) =
{
  .name = "wg6-output-tun",
  .vector_size = sizeof (u32),
  .format_trace = format_wg_output_tun_trace,
  .type = VLIB_NODE_TYPE_INTERNAL,
  .n_errors = ARRAY_LEN (wg_output_error_strings),
  .error_strings = wg_output_error_strings,
  .n_next_nodes = WG_OUTPUT_N_NEXT,
  .next_nodes = {
        [WG_OUTPUT_NEXT_HANDOFF] = "wg6-output-tun-handoff",
        [WG_OUTPUT_NEXT_INTERFACE_OUTPUT] = "adj-midchain-tx",
        [WG_OUTPUT_NEXT_ERROR] = "error-drop",
  },
};
/* *INDENT-ON* */

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