2 * esp_decrypt.c : IPSec ESP decrypt node
4 * Copyright (c) 2015 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/api_errno.h>
20 #include <vnet/ip/ip.h>
21 #include <vnet/l2/l2_input.h>
23 #include <vnet/ipsec/ipsec.h>
24 #include <vnet/ipsec/esp.h>
25 #include <vnet/ipsec/ipsec_io.h>
26 #include <vnet/ipsec/ipsec_tun.h>
28 #include <vnet/gre/gre.h>
30 #define foreach_esp_decrypt_next \
31 _(DROP, "error-drop") \
32 _(IP4_INPUT, "ip4-input-no-checksum") \
33 _(IP6_INPUT, "ip6-input") \
34 _(L2_INPUT, "l2-input") \
37 #define _(v, s) ESP_DECRYPT_NEXT_##v,
40 foreach_esp_decrypt_next
46 #define foreach_esp_decrypt_error \
47 _(RX_PKTS, "ESP pkts received") \
48 _(DECRYPTION_FAILED, "ESP decryption failed") \
49 _(INTEG_ERROR, "Integrity check failed") \
50 _(CRYPTO_ENGINE_ERROR, "crypto engine error (packet dropped)") \
51 _(REPLAY, "SA replayed packet") \
52 _(RUNT, "undersized packet") \
53 _(NO_BUFFERS, "no buffers (packet dropped)") \
54 _(OVERSIZED_HEADER, "buffer with oversized header (dropped)") \
55 _(NO_TAIL_SPACE, "no enough buffer tail space (dropped)") \
56 _(TUN_NO_PROTO, "no tunnel protocol") \
57 _(UNSUP_PAYLOAD, "unsupported payload") \
62 #define _(sym,str) ESP_DECRYPT_ERROR_##sym,
63 foreach_esp_decrypt_error
66 } esp_decrypt_error_t;
68 static char *esp_decrypt_error_strings[] = {
69 #define _(sym,string) string,
70 foreach_esp_decrypt_error
79 ipsec_crypto_alg_t crypto_alg;
80 ipsec_integ_alg_t integ_alg;
81 } esp_decrypt_trace_t;
83 /* packet trace format function */
85 format_esp_decrypt_trace (u8 * s, va_list * args)
87 CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
88 CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
89 esp_decrypt_trace_t *t = va_arg (*args, esp_decrypt_trace_t *);
93 "esp: crypto %U integrity %U pkt-seq %d sa-seq %u sa-seq-hi %u",
94 format_ipsec_crypto_alg, t->crypto_alg, format_ipsec_integ_alg,
95 t->integ_alg, t->seq, t->sa_seq, t->sa_seq_hi);
108 ipsec_sa_flags_t flags;
115 u32 free_buffer_index;
121 } esp_decrypt_packet_data_t;
123 STATIC_ASSERT_SIZEOF (esp_decrypt_packet_data_t, 4 * sizeof (u64));
125 #define ESP_ENCRYPT_PD_F_FD_TRANSPORT (1 << 2)
127 static_always_inline void
128 esp_process_ops (vlib_main_t * vm, vlib_node_runtime_t * node,
129 vnet_crypto_op_t * ops, vlib_buffer_t * b[], u16 * nexts,
132 vnet_crypto_op_t *op = ops;
133 u32 n_fail, n_ops = vec_len (ops);
138 n_fail = n_ops - vnet_crypto_process_ops (vm, op, n_ops);
142 ASSERT (op - ops < n_ops);
143 if (op->status != VNET_CRYPTO_OP_STATUS_COMPLETED)
145 u32 err, bi = op->user_data;
146 if (op->status == VNET_CRYPTO_OP_STATUS_FAIL_BAD_HMAC)
149 err = ESP_DECRYPT_ERROR_CRYPTO_ENGINE_ERROR;
150 b[bi]->error = node->errors[err];
151 nexts[bi] = ESP_DECRYPT_NEXT_DROP;
158 static_always_inline void
159 esp_process_chained_ops (vlib_main_t * vm, vlib_node_runtime_t * node,
160 vnet_crypto_op_t * ops, vlib_buffer_t * b[],
161 u16 * nexts, vnet_crypto_op_chunk_t * chunks, int e)
164 vnet_crypto_op_t *op = ops;
165 u32 n_fail, n_ops = vec_len (ops);
170 n_fail = n_ops - vnet_crypto_process_chained_ops (vm, op, chunks, n_ops);
174 ASSERT (op - ops < n_ops);
175 if (op->status != VNET_CRYPTO_OP_STATUS_COMPLETED)
177 u32 err, bi = op->user_data;
178 if (op->status == VNET_CRYPTO_OP_STATUS_FAIL_BAD_HMAC)
181 err = ESP_DECRYPT_ERROR_CRYPTO_ENGINE_ERROR;
182 b[bi]->error = node->errors[err];
183 nexts[bi] = ESP_DECRYPT_NEXT_DROP;
191 esp_remove_tail (vlib_main_t * vm, vlib_buffer_t * b, vlib_buffer_t * last,
194 vlib_buffer_t *before_last = b;
196 if (last->current_length > tail)
198 last->current_length -= tail;
201 ASSERT (b->flags & VLIB_BUFFER_NEXT_PRESENT);
203 while (b->flags & VLIB_BUFFER_NEXT_PRESENT)
206 b = vlib_get_buffer (vm, b->next_buffer);
208 before_last->current_length -= tail - last->current_length;
209 vlib_buffer_free_one (vm, before_last->next_buffer);
210 before_last->flags &= ~VLIB_BUFFER_NEXT_PRESENT;
213 /* ICV is splitted in last two buffers so move it to the last buffer and
214 return pointer to it */
215 static_always_inline u8 *
216 esp_move_icv (vlib_main_t * vm, vlib_buffer_t * first,
217 esp_decrypt_packet_data_t * pd, u16 icv_sz, u16 * dif)
219 vlib_buffer_t *before_last, *bp;
220 u16 last_sz = pd->lb->current_length;
221 u16 first_sz = icv_sz - last_sz;
223 bp = before_last = first;
224 while (bp->flags & VLIB_BUFFER_NEXT_PRESENT)
227 bp = vlib_get_buffer (vm, bp->next_buffer);
230 u8 *lb_curr = vlib_buffer_get_current (pd->lb);
231 memmove (lb_curr + first_sz, lb_curr, last_sz);
232 clib_memcpy_fast (lb_curr, vlib_buffer_get_tail (before_last) - first_sz,
234 before_last->current_length -= first_sz;
237 pd->lb = before_last;
239 pd->free_buffer_index = before_last->next_buffer;
240 before_last->flags &= ~VLIB_BUFFER_NEXT_PRESENT;
244 static_always_inline int
245 esp_insert_esn (vlib_main_t * vm, ipsec_sa_t * sa,
246 esp_decrypt_packet_data_t * pd, vnet_crypto_op_t * op,
247 u16 * len, vlib_buffer_t * b, u8 * payload)
249 if (!ipsec_sa_is_set_USE_ESN (sa))
252 /* shift ICV by 4 bytes to insert ESN */
253 u32 seq_hi = clib_host_to_net_u32 (sa->seq_hi);
254 u8 tmp[ESP_MAX_ICV_SIZE], sz = sizeof (sa->seq_hi);
258 u16 space_left = vlib_buffer_space_left_at_end (vm, pd->lb);
259 if (space_left >= sz)
261 clib_memcpy_fast (vlib_buffer_get_tail (pd->lb), &seq_hi, sz);
267 len[0] = b->current_length;
271 clib_memcpy_fast (tmp, payload + len[0], ESP_MAX_ICV_SIZE);
272 clib_memcpy_fast (payload + len[0], &seq_hi, sz);
273 clib_memcpy_fast (payload + len[0] + sz, tmp, ESP_MAX_ICV_SIZE);
280 static_always_inline u8 *
281 esp_move_icv_esn (vlib_main_t * vm, vlib_buffer_t * first,
282 esp_decrypt_packet_data_t * pd, u16 icv_sz, ipsec_sa_t * sa,
283 u8 * extra_esn, vnet_crypto_op_t * op)
286 u8 *digest = esp_move_icv (vm, first, pd, icv_sz, &dif);
290 if (ipsec_sa_is_set_USE_ESN (sa))
292 u8 sz = sizeof (sa->seq_hi);
293 u32 seq_hi = clib_host_to_net_u32 (sa->seq_hi);
294 u16 space_left = vlib_buffer_space_left_at_end (vm, pd->lb);
296 if (space_left >= sz)
298 clib_memcpy_fast (vlib_buffer_get_tail (pd->lb), &seq_hi, sz);
303 /* no space for ESN at the tail, use the next buffer
305 ASSERT (pd->icv_removed);
306 vlib_buffer_t *tmp = vlib_get_buffer (vm, pd->free_buffer_index);
307 clib_memcpy_fast (vlib_buffer_get_current (tmp) - sz, &seq_hi, sz);
315 esp_decrypt_inline (vlib_main_t * vm,
316 vlib_node_runtime_t * node, vlib_frame_t * from_frame,
317 int is_ip6, int is_tun)
319 ipsec_main_t *im = &ipsec_main;
320 u32 thread_index = vm->thread_index;
322 ipsec_per_thread_data_t *ptd = vec_elt_at_index (im->ptd, thread_index);
323 u32 *from = vlib_frame_vector_args (from_frame);
324 u32 n_left = from_frame->n_vectors;
325 vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b = bufs;
326 u16 nexts[VLIB_FRAME_SIZE], *next = nexts;
327 esp_decrypt_packet_data_t pkt_data[VLIB_FRAME_SIZE], *pd = pkt_data;
328 esp_decrypt_packet_data_t cpd = { };
329 u32 current_sa_index = ~0, current_sa_bytes = 0, current_sa_pkts = 0;
330 const u8 esp_sz = sizeof (esp_header_t);
332 vnet_crypto_op_t _op, *op = &_op;
333 vnet_crypto_op_chunk_t *ch;
334 vnet_crypto_op_t **crypto_ops = &ptd->crypto_ops;
335 vnet_crypto_op_t **integ_ops = &ptd->integ_ops;
337 vlib_get_buffers (vm, from, b, n_left);
338 vec_reset_length (ptd->crypto_ops);
339 vec_reset_length (ptd->integ_ops);
340 vec_reset_length (ptd->chained_crypto_ops);
341 vec_reset_length (ptd->chained_integ_ops);
342 vec_reset_length (ptd->chunks);
343 clib_memset_u16 (nexts, -1, n_left);
352 vlib_prefetch_buffer_header (b[2], LOAD);
353 p = vlib_buffer_get_current (b[1]);
354 CLIB_PREFETCH (p, CLIB_CACHE_LINE_BYTES, LOAD);
355 p -= CLIB_CACHE_LINE_BYTES;
356 CLIB_PREFETCH (p, CLIB_CACHE_LINE_BYTES, LOAD);
359 u32 n_bufs = vlib_buffer_chain_linearize (vm, b[0]);
362 b[0]->error = node->errors[ESP_DECRYPT_ERROR_NO_BUFFERS];
363 next[0] = ESP_DECRYPT_NEXT_DROP;
367 if (vnet_buffer (b[0])->ipsec.sad_index != current_sa_index)
370 vlib_increment_combined_counter (&ipsec_sa_counters, thread_index,
374 current_sa_bytes = current_sa_pkts = 0;
376 current_sa_index = vnet_buffer (b[0])->ipsec.sad_index;
377 sa0 = pool_elt_at_index (im->sad, current_sa_index);
378 cpd.icv_sz = sa0->integ_icv_size;
379 cpd.iv_sz = sa0->crypto_iv_size;
380 cpd.flags = sa0->flags;
381 cpd.sa_index = current_sa_index;
384 if (PREDICT_FALSE (~0 == sa0->decrypt_thread_index))
386 /* this is the first packet to use this SA, claim the SA
387 * for this thread. this could happen simultaneously on
389 clib_atomic_cmp_and_swap (&sa0->decrypt_thread_index, ~0,
390 ipsec_sa_assign_thread (thread_index));
393 if (PREDICT_TRUE (thread_index != sa0->decrypt_thread_index))
395 next[0] = ESP_DECRYPT_NEXT_HANDOFF;
399 /* store packet data for next round for easier prefetch */
400 pd->sa_data = cpd.sa_data;
401 pd->current_data = b[0]->current_data;
402 pd->hdr_sz = pd->current_data - vnet_buffer (b[0])->l3_hdr_offset;
403 payload = b[0]->data + pd->current_data;
404 pd->seq = clib_host_to_net_u32 (((esp_header_t *) payload)->seq);
405 pd->free_buffer_index = 0;
411 /* find last buffer in the chain */
412 while (pd->lb->flags & VLIB_BUFFER_NEXT_PRESENT)
413 pd->lb = vlib_get_buffer (vm, pd->lb->next_buffer);
415 crypto_ops = &ptd->chained_crypto_ops;
416 integ_ops = &ptd->chained_integ_ops;
418 pd->current_length = b[0]->current_length;
420 /* anti-reply check */
421 if (ipsec_sa_anti_replay_check (sa0, pd->seq))
423 b[0]->error = node->errors[ESP_DECRYPT_ERROR_REPLAY];
424 next[0] = ESP_DECRYPT_NEXT_DROP;
428 if (pd->current_length < cpd.icv_sz + esp_sz + cpd.iv_sz)
430 b[0]->error = node->errors[ESP_DECRYPT_ERROR_RUNT];
431 next[0] = ESP_DECRYPT_NEXT_DROP;
435 len = pd->current_length - cpd.icv_sz;
436 current_sa_pkts += 1;
437 current_sa_bytes += vlib_buffer_length_in_chain (vm, b[0]);
439 if (PREDICT_TRUE (sa0->integ_op_id != VNET_CRYPTO_OP_NONE))
441 vnet_crypto_op_init (op, sa0->integ_op_id);
442 op->key_index = sa0->integ_key_index;
444 op->flags = VNET_CRYPTO_OP_FLAG_HMAC_CHECK;
445 op->user_data = b - bufs;
446 op->digest = payload + len;
447 op->digest_len = cpd.icv_sz;
452 /* buffer is chained */
453 vlib_buffer_t *cb = b[0];
454 op->len = pd->current_length;
456 /* special case when ICV is splitted and needs to be reassembled
457 * first -> move it to the last buffer. Also take into account
458 * that ESN needs to be added after encrypted data and may or
459 * may not fit in the tail.*/
460 if (pd->lb->current_length < cpd.icv_sz)
464 esp_move_icv_esn (vm, b[0], pd, cpd.icv_sz, sa0,
469 /* esn is in the last buffer, that was unlinked from
471 op->len = b[0]->current_length;
477 /* we now have a single buffer of crypto data, adjust
478 * the length (second buffer contains only ICV) */
479 integ_ops = &ptd->integ_ops;
480 crypto_ops = &ptd->crypto_ops;
481 len = b[0]->current_length;
487 op->digest = vlib_buffer_get_tail (pd->lb) - cpd.icv_sz;
489 op->flags |= VNET_CRYPTO_OP_FLAG_CHAINED_BUFFERS;
490 op->chunk_index = vec_len (ptd->chunks);
491 vec_add2 (ptd->chunks, ch, 1);
492 ch->len = pd->current_length;
494 cb = vlib_get_buffer (vm, cb->next_buffer);
498 vec_add2 (ptd->chunks, ch, 1);
500 ch->src = vlib_buffer_get_current (cb);
504 ch->len = cb->current_length;
506 ch->len = cb->current_length - cpd.icv_sz;
507 if (ipsec_sa_is_set_USE_ESN (sa0))
509 u32 seq_hi = clib_host_to_net_u32 (sa0->seq_hi);
510 u8 tmp[ESP_MAX_ICV_SIZE], sz = sizeof (sa0->seq_hi);
512 vlib_buffer_t *tmp_b;
513 u16 space_left = vlib_buffer_space_left_at_end
519 /* use pre-data area from the last bufer
520 that was removed from the chain */
523 pd->free_buffer_index);
524 esn = tmp_b->data - sz;
528 /* no space, need to allocate new buffer */
530 if (1 != vlib_buffer_alloc (vm, &tmp_bi, 1))
532 b[0]->error = node->errors
533 [ESP_DECRYPT_ERROR_NO_BUFFERS];
534 next[0] = ESP_DECRYPT_NEXT_DROP;
537 tmp_b = vlib_get_buffer (vm, tmp_bi);
539 pd->free_buffer_index = tmp_bi;
541 clib_memcpy_fast (esn, &seq_hi, sz);
543 vec_add2 (ptd->chunks, ch, 1);
552 clib_memcpy_fast (vlib_buffer_get_tail
553 (pd->lb), &seq_hi, sz);
557 clib_memcpy_fast (tmp, op->digest,
559 clib_memcpy_fast (op->digest, &seq_hi, sz);
560 clib_memcpy_fast (op->digest + sz, tmp,
570 ch->len = cb->current_length;
572 if (!(cb->flags & VLIB_BUFFER_NEXT_PRESENT))
575 cb = vlib_get_buffer (vm, cb->next_buffer);
579 esp_insert_esn (vm, sa0, pd, op, &len, b[0], payload);
581 vec_add_aligned (integ_ops[0], op, 1, CLIB_CACHE_LINE_BYTES);
587 if (sa0->crypto_dec_op_id != VNET_CRYPTO_OP_NONE)
589 vnet_crypto_op_init (op, sa0->crypto_dec_op_id);
590 op->key_index = sa0->crypto_key_index;
593 if (ipsec_sa_is_set_IS_AEAD (sa0))
600 * construct the AAD and the nonce (Salt || IV) in a scratch
601 * space in front of the IP header.
603 scratch = payload - esp_sz;
604 esp0 = (esp_header_t *) (scratch);
606 scratch -= (sizeof (*aad) + pd->hdr_sz);
609 esp_aad_fill (op, esp0, sa0);
612 * we don't need to refer to the ESP header anymore so we
613 * can overwrite it with the salt and use the IV where it is
614 * to form the nonce = (Salt + IV)
616 op->iv -= sizeof (sa0->salt);
617 clib_memcpy_fast (op->iv, &sa0->salt, sizeof (sa0->salt));
619 op->tag = payload + len;
622 op->src = op->dst = payload += cpd.iv_sz;
623 op->len = len - cpd.iv_sz;
624 op->user_data = b - bufs;
628 /* buffer is chained */
629 vlib_buffer_t *cb = b[0];
630 op->flags |= VNET_CRYPTO_OP_FLAG_CHAINED_BUFFERS;
631 op->chunk_index = vec_len (ptd->chunks);
632 vec_add2 (ptd->chunks, ch, 1);
633 ch->len = len - cpd.iv_sz + cpd.icv_sz;
634 ch->src = ch->dst = payload;
635 cb = vlib_get_buffer (vm, cb->next_buffer);
640 vec_add2 (ptd->chunks, ch, 1);
642 ch->src = ch->dst = vlib_buffer_get_current (cb);
645 if (ipsec_sa_is_set_IS_AEAD (sa0))
647 if (pd->lb->current_length < cpd.icv_sz)
651 esp_move_icv (vm, b[0], pd, cpd.icv_sz, &dif);
653 /* this chunk does not contain crypto data */
656 /* and fix previous chunk's length as it might have
658 ASSERT (op->n_chunks > 0);
662 ch[-1].len = pd->lb->current_length;
667 vlib_buffer_get_tail (pd->lb) - cpd.icv_sz;
671 ch->len = cb->current_length;
673 ch->len = cb->current_length - cpd.icv_sz;
676 ch->len = cb->current_length;
678 if (!(cb->flags & VLIB_BUFFER_NEXT_PRESENT))
681 cb = vlib_get_buffer (vm, cb->next_buffer);
685 vec_add_aligned (crypto_ops[0], op, 1, CLIB_CACHE_LINE_BYTES);
696 if (PREDICT_TRUE (~0 != current_sa_index))
697 vlib_increment_combined_counter (&ipsec_sa_counters, thread_index,
698 current_sa_index, current_sa_pkts,
701 esp_process_ops (vm, node, ptd->integ_ops, bufs, nexts,
702 ESP_DECRYPT_ERROR_INTEG_ERROR);
703 esp_process_chained_ops (vm, node, ptd->chained_integ_ops, bufs, nexts,
704 ptd->chunks, ESP_DECRYPT_ERROR_INTEG_ERROR);
706 esp_process_ops (vm, node, ptd->crypto_ops, bufs, nexts,
707 ESP_DECRYPT_ERROR_DECRYPTION_FAILED);
708 esp_process_chained_ops (vm, node, ptd->chained_crypto_ops, bufs, nexts,
709 ptd->chunks, ESP_DECRYPT_ERROR_DECRYPTION_FAILED);
711 /* Post decryption ronud - adjust packet data start and length and next
714 n_left = from_frame->n_vectors;
721 const u8 tun_flags = IPSEC_SA_FLAG_IS_TUNNEL |
722 IPSEC_SA_FLAG_IS_TUNNEL_V6;
726 void *data = b[1]->data + pd[1].current_data;
728 /* buffer metadata */
729 vlib_prefetch_buffer_header (b[1], LOAD);
732 CLIB_PREFETCH (data + pd[1].current_length - pd[1].icv_sz - 2,
733 CLIB_CACHE_LINE_BYTES, LOAD);
736 CLIB_PREFETCH (data - CLIB_CACHE_LINE_BYTES,
737 CLIB_CACHE_LINE_BYTES * 2, LOAD);
740 if (next[0] < ESP_DECRYPT_N_NEXT)
743 sa0 = vec_elt_at_index (im->sad, pd->sa_index);
746 * redo the anti-reply check
747 * in this frame say we have sequence numbers, s, s+1, s+1, s+1
748 * and s and s+1 are in the window. When we did the anti-replay
749 * check above we did so against the state of the window (W),
750 * after packet s-1. So each of the packets in the sequence will be
752 * This time s will be cheked against Ws-1, s+1 chceked against Ws
753 * (i.e. the window state is updated/advnaced)
754 * so this time the successive s+! packet will be dropped.
755 * This is a consequence of batching the decrypts. If the
756 * check-dcrypt-advance process was done for each packet it would
757 * be fine. But we batch the decrypts because it's much more efficient
758 * to do so in SW and if we offload to HW and the process is async.
760 * You're probably thinking, but this means an attacker can send the
761 * above sequence and cause VPP to perform decrpyts that will fail,
762 * and that's true. But if the attacker can determine s (a valid
763 * sequence number in the window) which is non-trivial, it can generate
764 * a sequence s, s+1, s+2, s+3, ... s+n and nothing will prevent any
765 * implementation, sequential or batching, from decrypting these.
767 if (ipsec_sa_anti_replay_check (sa0, pd->seq))
769 b[0]->error = node->errors[ESP_DECRYPT_ERROR_REPLAY];
770 next[0] = ESP_DECRYPT_NEXT_DROP;
774 ipsec_sa_anti_replay_advance (sa0, pd->seq);
776 u8 pad_length = 0, next_header = 0;
777 u16 icv_sz = pd->icv_removed ? 0 : pd->icv_sz;
779 if (pd->free_buffer_index)
780 vlib_buffer_free_one (vm, pd->free_buffer_index);
782 if (pd->lb->current_length < sizeof (esp_footer_t) + icv_sz)
784 /* esp footer is either splitted in two buffers or in the before
787 vlib_buffer_t *before_last = b[0], *bp = b[0];
788 while (bp->flags & VLIB_BUFFER_NEXT_PRESENT)
791 bp = vlib_get_buffer (vm, bp->next_buffer);
793 u8 *bt = vlib_buffer_get_tail (before_last);
795 if (pd->lb->current_length == icv_sz)
797 esp_footer_t *f = (esp_footer_t *) (bt - sizeof (*f));
798 pad_length = f->pad_length;
799 next_header = f->next_header;
803 pad_length = (bt - 1)[0];
804 next_header = ((u8 *) vlib_buffer_get_current (pd->lb))[0];
810 (esp_footer_t *) (pd->lb->data + pd->lb->current_data +
811 pd->lb->current_length - sizeof (esp_footer_t) -
813 pad_length = f->pad_length;
814 next_header = f->next_header;
817 u16 adv = pd->iv_sz + esp_sz;
818 u16 tail = sizeof (esp_footer_t) + pad_length + icv_sz;
819 u16 tail_orig = sizeof (esp_footer_t) + pad_length + pd->icv_sz;
820 b[0]->flags &= ~VLIB_BUFFER_TOTAL_LENGTH_VALID;
822 if ((pd->flags & tun_flags) == 0 && !is_tun) /* transport mode */
824 u8 udp_sz = (is_ip6 == 0 && pd->flags & IPSEC_SA_FLAG_UDP_ENCAP) ?
825 sizeof (udp_header_t) : 0;
826 u16 ip_hdr_sz = pd->hdr_sz - udp_sz;
827 u8 *old_ip = b[0]->data + pd->current_data - ip_hdr_sz - udp_sz;
828 u8 *ip = old_ip + adv + udp_sz;
830 if (is_ip6 && ip_hdr_sz > 64)
831 memmove (ip, old_ip, ip_hdr_sz);
833 clib_memcpy_le64 (ip, old_ip, ip_hdr_sz);
835 b[0]->current_data = pd->current_data + adv - ip_hdr_sz;
836 b[0]->current_length += ip_hdr_sz - adv;
837 esp_remove_tail (vm, b[0], pd->lb, tail);
841 ip6_header_t *ip6 = (ip6_header_t *) ip;
842 u16 len = clib_net_to_host_u16 (ip6->payload_length);
843 len -= adv + tail_orig;
844 ip6->payload_length = clib_host_to_net_u16 (len);
845 ip6->protocol = next_header;
846 next[0] = ESP_DECRYPT_NEXT_IP6_INPUT;
850 ip4_header_t *ip4 = (ip4_header_t *) ip;
851 ip_csum_t sum = ip4->checksum;
852 u16 len = clib_net_to_host_u16 (ip4->length);
853 len = clib_host_to_net_u16 (len - adv - tail_orig - udp_sz);
854 sum = ip_csum_update (sum, ip4->protocol, next_header,
855 ip4_header_t, protocol);
856 sum = ip_csum_update (sum, ip4->length, len,
857 ip4_header_t, length);
858 ip4->checksum = ip_csum_fold (sum);
859 ip4->protocol = next_header;
861 next[0] = ESP_DECRYPT_NEXT_IP4_INPUT;
866 if (PREDICT_TRUE (next_header == IP_PROTOCOL_IP_IN_IP))
868 next[0] = ESP_DECRYPT_NEXT_IP4_INPUT;
869 b[0]->current_data = pd->current_data + adv;
870 b[0]->current_length = pd->current_length - adv;
871 esp_remove_tail (vm, b[0], pd->lb, tail);
873 else if (next_header == IP_PROTOCOL_IPV6)
875 next[0] = ESP_DECRYPT_NEXT_IP6_INPUT;
876 b[0]->current_data = pd->current_data + adv;
877 b[0]->current_length = pd->current_length - adv;
878 esp_remove_tail (vm, b[0], pd->lb, tail);
882 if (is_tun && next_header == IP_PROTOCOL_GRE)
886 b[0]->current_data = pd->current_data + adv;
887 b[0]->current_length = pd->current_length - adv - tail;
889 gre = vlib_buffer_get_current (b[0]);
891 vlib_buffer_advance (b[0], sizeof (*gre));
893 switch (clib_net_to_host_u16 (gre->protocol))
895 case GRE_PROTOCOL_teb:
896 vnet_update_l2_len (b[0]);
897 next[0] = ESP_DECRYPT_NEXT_L2_INPUT;
899 case GRE_PROTOCOL_ip4:
900 next[0] = ESP_DECRYPT_NEXT_IP4_INPUT;
902 case GRE_PROTOCOL_ip6:
903 next[0] = ESP_DECRYPT_NEXT_IP6_INPUT;
907 node->errors[ESP_DECRYPT_ERROR_UNSUP_PAYLOAD];
908 next[0] = ESP_DECRYPT_NEXT_DROP;
914 next[0] = ESP_DECRYPT_NEXT_DROP;
915 b[0]->error = node->errors[ESP_DECRYPT_ERROR_UNSUP_PAYLOAD];
921 if (ipsec_sa_is_set_IS_PROTECT (sa0))
924 * There are two encap possibilities
925 * 1) the tunnel and ths SA are prodiving encap, i.e. it's
926 * MAC | SA-IP | TUN-IP | ESP | PAYLOAD
927 * implying the SA is in tunnel mode (on a tunnel interface)
928 * 2) only the tunnel provides encap
929 * MAC | TUN-IP | ESP | PAYLOAD
930 * implying the SA is in transport mode.
932 * For 2) we need only strip the tunnel encap and we're good.
933 * since the tunnel and crypto ecnap (int the tun=protect
934 * object) are the same and we verified above that these match
935 * for 1) we need to strip the SA-IP outer headers, to
936 * reveal the tunnel IP and then check that this matches
937 * the configured tunnel.
939 const ipsec_tun_protect_t *itp;
941 itp = ipsec_tun_protect_get
942 (vnet_buffer (b[0])->ipsec.protect_index);
944 if (PREDICT_TRUE (next_header == IP_PROTOCOL_IP_IN_IP))
946 const ip4_header_t *ip4;
948 ip4 = vlib_buffer_get_current (b[0]);
950 if (!ip46_address_is_equal_v4 (&itp->itp_tun.src,
951 &ip4->dst_address) ||
952 !ip46_address_is_equal_v4 (&itp->itp_tun.dst,
955 next[0] = ESP_DECRYPT_NEXT_DROP;
957 node->errors[ESP_DECRYPT_ERROR_TUN_NO_PROTO];
960 else if (next_header == IP_PROTOCOL_IPV6)
962 const ip6_header_t *ip6;
964 ip6 = vlib_buffer_get_current (b[0]);
966 if (!ip46_address_is_equal_v6 (&itp->itp_tun.src,
967 &ip6->dst_address) ||
968 !ip46_address_is_equal_v6 (&itp->itp_tun.dst,
971 next[0] = ESP_DECRYPT_NEXT_DROP;
973 node->errors[ESP_DECRYPT_ERROR_TUN_NO_PROTO];
981 if (PREDICT_FALSE (b[0]->flags & VLIB_BUFFER_IS_TRACED))
983 esp_decrypt_trace_t *tr;
984 tr = vlib_add_trace (vm, node, b[0], sizeof (*tr));
985 sa0 = pool_elt_at_index (im->sad,
986 vnet_buffer (b[0])->ipsec.sad_index);
987 tr->crypto_alg = sa0->crypto_alg;
988 tr->integ_alg = sa0->integ_alg;
990 tr->sa_seq = sa0->last_seq;
991 tr->sa_seq_hi = sa0->seq_hi;
1001 n_left = from_frame->n_vectors;
1002 vlib_node_increment_counter (vm, node->node_index,
1003 ESP_DECRYPT_ERROR_RX_PKTS, n_left);
1005 vlib_buffer_enqueue_to_next (vm, node, from, nexts, n_left);
1010 VLIB_NODE_FN (esp4_decrypt_node) (vlib_main_t * vm,
1011 vlib_node_runtime_t * node,
1012 vlib_frame_t * from_frame)
1014 return esp_decrypt_inline (vm, node, from_frame, 0, 0);
1017 VLIB_NODE_FN (esp4_decrypt_tun_node) (vlib_main_t * vm,
1018 vlib_node_runtime_t * node,
1019 vlib_frame_t * from_frame)
1021 return esp_decrypt_inline (vm, node, from_frame, 0, 1);
1024 VLIB_NODE_FN (esp6_decrypt_node) (vlib_main_t * vm,
1025 vlib_node_runtime_t * node,
1026 vlib_frame_t * from_frame)
1028 return esp_decrypt_inline (vm, node, from_frame, 1, 0);
1031 VLIB_NODE_FN (esp6_decrypt_tun_node) (vlib_main_t * vm,
1032 vlib_node_runtime_t * node,
1033 vlib_frame_t * from_frame)
1035 return esp_decrypt_inline (vm, node, from_frame, 1, 1);
1039 VLIB_REGISTER_NODE (esp4_decrypt_node) = {
1040 .name = "esp4-decrypt",
1041 .vector_size = sizeof (u32),
1042 .format_trace = format_esp_decrypt_trace,
1043 .type = VLIB_NODE_TYPE_INTERNAL,
1045 .n_errors = ARRAY_LEN(esp_decrypt_error_strings),
1046 .error_strings = esp_decrypt_error_strings,
1048 .n_next_nodes = ESP_DECRYPT_N_NEXT,
1050 [ESP_DECRYPT_NEXT_DROP] = "ip4-drop",
1051 [ESP_DECRYPT_NEXT_IP4_INPUT] = "ip4-input-no-checksum",
1052 [ESP_DECRYPT_NEXT_IP6_INPUT] = "ip6-input",
1053 [ESP_DECRYPT_NEXT_L2_INPUT] = "l2-input",
1054 [ESP_DECRYPT_NEXT_HANDOFF] = "esp4-decrypt-handoff",
1058 VLIB_REGISTER_NODE (esp6_decrypt_node) = {
1059 .name = "esp6-decrypt",
1060 .vector_size = sizeof (u32),
1061 .format_trace = format_esp_decrypt_trace,
1062 .type = VLIB_NODE_TYPE_INTERNAL,
1064 .n_errors = ARRAY_LEN(esp_decrypt_error_strings),
1065 .error_strings = esp_decrypt_error_strings,
1067 .n_next_nodes = ESP_DECRYPT_N_NEXT,
1069 [ESP_DECRYPT_NEXT_DROP] = "ip6-drop",
1070 [ESP_DECRYPT_NEXT_IP4_INPUT] = "ip4-input-no-checksum",
1071 [ESP_DECRYPT_NEXT_IP6_INPUT] = "ip6-input",
1072 [ESP_DECRYPT_NEXT_L2_INPUT] = "l2-input",
1073 [ESP_DECRYPT_NEXT_HANDOFF]= "esp6-decrypt-handoff",
1077 VLIB_REGISTER_NODE (esp4_decrypt_tun_node) = {
1078 .name = "esp4-decrypt-tun",
1079 .vector_size = sizeof (u32),
1080 .format_trace = format_esp_decrypt_trace,
1081 .type = VLIB_NODE_TYPE_INTERNAL,
1082 .n_errors = ARRAY_LEN(esp_decrypt_error_strings),
1083 .error_strings = esp_decrypt_error_strings,
1084 .n_next_nodes = ESP_DECRYPT_N_NEXT,
1086 [ESP_DECRYPT_NEXT_DROP] = "ip4-drop",
1087 [ESP_DECRYPT_NEXT_IP4_INPUT] = "ip4-input-no-checksum",
1088 [ESP_DECRYPT_NEXT_IP6_INPUT] = "ip6-input",
1089 [ESP_DECRYPT_NEXT_L2_INPUT] = "l2-input",
1090 [ESP_DECRYPT_NEXT_HANDOFF] = "esp4-decrypt-tun-handoff",
1094 VLIB_REGISTER_NODE (esp6_decrypt_tun_node) = {
1095 .name = "esp6-decrypt-tun",
1096 .vector_size = sizeof (u32),
1097 .format_trace = format_esp_decrypt_trace,
1098 .type = VLIB_NODE_TYPE_INTERNAL,
1099 .n_errors = ARRAY_LEN(esp_decrypt_error_strings),
1100 .error_strings = esp_decrypt_error_strings,
1101 .n_next_nodes = ESP_DECRYPT_N_NEXT,
1103 [ESP_DECRYPT_NEXT_DROP] = "ip6-drop",
1104 [ESP_DECRYPT_NEXT_IP4_INPUT] = "ip4-input-no-checksum",
1105 [ESP_DECRYPT_NEXT_IP6_INPUT] = "ip6-input",
1106 [ESP_DECRYPT_NEXT_L2_INPUT] = "l2-input",
1107 [ESP_DECRYPT_NEXT_HANDOFF]= "esp6-decrypt-tun-handoff",
1113 * fd.io coding-style-patch-verification: ON
1116 * eval: (c-set-style "gnu")