2 * esp_encrypt.c : IPSec ESP encrypt 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/udp/udp.h>
23 #include <vnet/crypto/crypto.h>
25 #include <vnet/ipsec/ipsec.h>
26 #include <vnet/ipsec/esp.h>
28 #define foreach_esp_encrypt_next \
29 _(DROP, "error-drop") \
30 _(IP4_LOOKUP, "ip4-lookup") \
31 _(IP6_LOOKUP, "ip6-lookup") \
32 _(INTERFACE_OUTPUT, "interface-output")
34 #define _(v, s) ESP_ENCRYPT_NEXT_##v,
37 foreach_esp_encrypt_next
42 #define foreach_esp_encrypt_error \
43 _(RX_PKTS, "ESP pkts received") \
44 _(SEQ_CYCLED, "sequence number cycled (packet dropped)") \
45 _(CRYPTO_ENGINE_ERROR, "crypto engine error (packet dropped)") \
46 _(CHAINED_BUFFER, "chained buffers (packet dropped)") \
47 _(NO_TRAILER_SPACE, "no trailer space (packet dropped)")
51 #define _(sym,str) ESP_ENCRYPT_ERROR_##sym,
52 foreach_esp_encrypt_error
55 } esp_encrypt_error_t;
57 static char *esp_encrypt_error_strings[] = {
58 #define _(sym,string) string,
59 foreach_esp_encrypt_error
69 ipsec_crypto_alg_t crypto_alg;
70 ipsec_integ_alg_t integ_alg;
71 } esp_encrypt_trace_t;
73 /* packet trace format function */
75 format_esp_encrypt_trace (u8 * s, va_list * args)
77 CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
78 CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
79 esp_encrypt_trace_t *t = va_arg (*args, esp_encrypt_trace_t *);
81 s = format (s, "esp: sa-index %d spi %u seq %u crypto %U integrity %U%s",
82 t->sa_index, t->spi, t->seq,
83 format_ipsec_crypto_alg, t->crypto_alg,
84 format_ipsec_integ_alg, t->integ_alg,
85 t->udp_encap ? " udp-encap-enabled" : "");
89 /* pad packet in input buffer */
90 static_always_inline u8 *
91 esp_add_footer_and_icv (vlib_buffer_t * b, u8 block_size, u8 icv_sz)
93 static const u8 pad_data[ESP_MAX_BLOCK_SIZE] = {
94 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08,
95 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x00, 0x00,
98 u16 min_length = b->current_length + sizeof (esp_footer_t);
99 u16 new_length = round_pow2 (min_length, block_size);
100 u8 pad_bytes = new_length - min_length;
101 esp_footer_t *f = (esp_footer_t *) (vlib_buffer_get_current (b) +
102 new_length - sizeof (esp_footer_t));
105 clib_memcpy_fast ((u8 *) f - pad_bytes, pad_data, ESP_MAX_BLOCK_SIZE);
107 f->pad_length = pad_bytes;
108 b->current_length = new_length + icv_sz;
109 return &f->next_header;
112 static_always_inline void
113 esp_update_ip4_hdr (ip4_header_t * ip4, u16 len, int is_transport, int is_udp)
118 len = clib_net_to_host_u16 (len);
119 old_len = ip4->length;
123 u8 prot = is_udp ? IP_PROTOCOL_UDP : IP_PROTOCOL_IPSEC_ESP;
125 sum = ip_csum_update (ip4->checksum, ip4->protocol,
126 prot, ip4_header_t, protocol);
127 ip4->protocol = prot;
129 sum = ip_csum_update (sum, old_len, len, ip4_header_t, length);
132 sum = ip_csum_update (ip4->checksum, old_len, len, ip4_header_t, length);
135 ip4->checksum = ip_csum_fold (sum);
138 static_always_inline void
139 esp_fill_udp_hdr (ipsec_sa_t * sa, udp_header_t * udp, u16 len)
141 clib_memcpy_fast (udp, &sa->udp_hdr, sizeof (udp_header_t));
142 udp->length = clib_net_to_host_u16 (len);
145 static_always_inline u8
146 ext_hdr_is_pre_esp (u8 nexthdr)
148 #ifdef CLIB_HAVE_VEC128
149 static const u8x16 ext_hdr_types = {
150 IP_PROTOCOL_IP6_HOP_BY_HOP_OPTIONS,
151 IP_PROTOCOL_IPV6_ROUTE,
152 IP_PROTOCOL_IPV6_FRAGMENTATION,
155 return !u8x16_is_all_zero (ext_hdr_types == u8x16_splat (nexthdr));
157 return ((nexthdr ^ IP_PROTOCOL_IP6_HOP_BY_HOP_OPTIONS) |
158 (nexthdr ^ IP_PROTOCOL_IPV6_ROUTE) |
159 (nexthdr ^ IP_PROTOCOL_IPV6_FRAGMENTATION) != 0);
163 static_always_inline u8
164 esp_get_ip6_hdr_len (ip6_header_t * ip6)
166 /* this code assumes that HbH, route and frag headers will be before
167 others, if that is not the case, they will end up encrypted */
169 u8 len = sizeof (ip6_header_t);
172 /* if next packet doesn't have ext header */
173 if (ext_hdr_is_pre_esp (ip6->protocol) == 0)
176 p = (void *) (ip6 + 1);
177 len += ip6_ext_header_len (p);
179 while (ext_hdr_is_pre_esp (p->next_hdr))
181 len += ip6_ext_header_len (p);
182 p = ip6_ext_next_header (p);
188 static_always_inline int
189 esp_trailer_icv_overflow (vlib_node_runtime_t * node, vlib_buffer_t * b,
190 u16 * next, u16 buffer_data_size)
192 if (b->current_data + b->current_length <= buffer_data_size)
195 b->current_length -= buffer_data_size - b->current_data;
196 b->error = node->errors[ESP_ENCRYPT_ERROR_NO_TRAILER_SPACE];
197 next[0] = ESP_ENCRYPT_NEXT_DROP;
201 static_always_inline void
202 esp_process_ops (vlib_main_t * vm, vlib_node_runtime_t * node,
203 vnet_crypto_op_t * ops, vlib_buffer_t * b[], u16 * nexts)
205 u32 n_fail, n_ops = vec_len (ops);
206 vnet_crypto_op_t *op = ops;
211 n_fail = n_ops - vnet_crypto_process_ops (vm, op, n_ops);
215 ASSERT (op - ops < n_ops);
217 if (op->status != VNET_CRYPTO_OP_STATUS_COMPLETED)
219 u32 bi = op->user_data;
220 b[bi]->error = node->errors[ESP_ENCRYPT_ERROR_CRYPTO_ENGINE_ERROR];
221 nexts[bi] = ESP_ENCRYPT_NEXT_DROP;
232 } __clib_packed esp_gcm_nonce_t;
234 STATIC_ASSERT_SIZEOF (esp_gcm_nonce_t, 12);
237 esp_encrypt_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
238 vlib_frame_t * frame, int is_ip6, int is_tun)
240 ipsec_main_t *im = &ipsec_main;
241 ipsec_per_thread_data_t *ptd = vec_elt_at_index (im->ptd, vm->thread_index);
242 u32 *from = vlib_frame_vector_args (frame);
243 u32 n_left = frame->n_vectors;
244 vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b = bufs;
245 u16 nexts[VLIB_FRAME_SIZE], *next = nexts;
246 esp_gcm_nonce_t nonces[VLIB_FRAME_SIZE], *nonce = nonces;
247 u32 thread_index = vm->thread_index;
248 u16 buffer_data_size = vlib_buffer_get_default_data_size (vm);
249 u32 current_sa_index = ~0, current_sa_packets = 0;
250 u32 current_sa_bytes = 0, spi = 0;
251 u8 block_sz = 0, iv_sz = 0, icv_sz = 0;
254 vlib_get_buffers (vm, from, b, n_left);
255 vec_reset_length (ptd->crypto_ops);
256 vec_reset_length (ptd->integ_ops);
263 u8 *payload, *next_hdr_ptr;
270 vlib_prefetch_buffer_header (b[2], LOAD);
271 p = vlib_buffer_get_current (b[1]);
272 CLIB_PREFETCH (p, CLIB_CACHE_LINE_BYTES, LOAD);
273 p -= CLIB_CACHE_LINE_BYTES;
274 CLIB_PREFETCH (p, CLIB_CACHE_LINE_BYTES, LOAD);
279 /* we are on a ipsec tunnel's feature arc */
281 sa_index0 = *(u32 *) vnet_feature_next_with_data (&next0, b[0],
287 sa_index0 = vnet_buffer (b[0])->ipsec.sad_index;
289 if (sa_index0 != current_sa_index)
291 if (current_sa_packets)
292 vlib_increment_combined_counter (&ipsec_sa_counters, thread_index,
296 current_sa_packets = current_sa_bytes = 0;
298 sa0 = pool_elt_at_index (im->sad, sa_index0);
299 current_sa_index = sa_index0;
300 spi = clib_net_to_host_u32 (sa0->spi);
301 block_sz = sa0->crypto_block_size;
302 icv_sz = sa0->integ_icv_size;
303 iv_sz = sa0->crypto_iv_size;
306 if (vlib_buffer_chain_linearize (vm, b[0]) != 1)
308 b[0]->error = node->errors[ESP_ENCRYPT_ERROR_CHAINED_BUFFER];
309 next[0] = ESP_ENCRYPT_NEXT_DROP;
313 if (PREDICT_FALSE (esp_seq_advance (sa0)))
315 b[0]->error = node->errors[ESP_ENCRYPT_ERROR_SEQ_CYCLED];
316 next[0] = ESP_ENCRYPT_NEXT_DROP;
323 if (ipsec_sa_is_set_IS_TUNNEL (sa0))
325 payload = vlib_buffer_get_current (b[0]);
326 next_hdr_ptr = esp_add_footer_and_icv (b[0], block_sz, icv_sz);
327 payload_len = b[0]->current_length;
329 if (esp_trailer_icv_overflow (node, b[0], next, buffer_data_size))
333 hdr_len += sizeof (*esp);
334 esp = (esp_header_t *) (payload - hdr_len);
336 /* optional UDP header */
337 if (ipsec_sa_is_set_UDP_ENCAP (sa0))
339 hdr_len += sizeof (udp_header_t);
340 esp_fill_udp_hdr (sa0, (udp_header_t *) (payload - hdr_len),
341 payload_len + hdr_len);
345 if (ipsec_sa_is_set_IS_TUNNEL_V6 (sa0))
348 u16 len = sizeof (ip6_header_t);
350 ip6 = (ip6_header_t *) (payload - hdr_len);
351 clib_memcpy_fast (ip6, &sa0->ip6_hdr, len);
352 *next_hdr_ptr = (is_ip6 ?
353 IP_PROTOCOL_IPV6 : IP_PROTOCOL_IP_IN_IP);
354 len = payload_len + hdr_len - len;
355 ip6->payload_length = clib_net_to_host_u16 (len);
360 u16 len = sizeof (ip4_header_t);
362 ip4 = (ip4_header_t *) (payload - hdr_len);
363 clib_memcpy_fast (ip4, &sa0->ip4_hdr, len);
364 *next_hdr_ptr = (is_ip6 ?
365 IP_PROTOCOL_IPV6 : IP_PROTOCOL_IP_IN_IP);
366 len = payload_len + hdr_len;
367 esp_update_ip4_hdr (ip4, len, /* is_transport */ 0, 0);
370 dpo = sa0->dpo + IPSEC_PROTOCOL_ESP;
373 next[0] = dpo->dpoi_next_node;
374 vnet_buffer (b[0])->ip.adj_index[VLIB_TX] = dpo->dpoi_index;
377 else /* transport mode */
379 u8 *l2_hdr, l2_len, *ip_hdr, ip_len;
380 udp_header_t *udp = 0;
381 u8 *old_ip_hdr = vlib_buffer_get_current (b[0]);
384 esp_get_ip6_hdr_len ((ip6_header_t *) old_ip_hdr) :
385 ip4_header_bytes ((ip4_header_t *) old_ip_hdr);
387 vlib_buffer_advance (b[0], ip_len);
388 payload = vlib_buffer_get_current (b[0]);
389 next_hdr_ptr = esp_add_footer_and_icv (b[0], block_sz, icv_sz);
390 payload_len = b[0]->current_length;
392 if (esp_trailer_icv_overflow (node, b[0], next, buffer_data_size))
396 hdr_len += sizeof (*esp);
397 esp = (esp_header_t *) (payload - hdr_len);
399 /* optional UDP header */
400 if (ipsec_sa_is_set_UDP_ENCAP (sa0))
402 hdr_len += sizeof (udp_header_t);
403 udp = (udp_header_t *) (payload - hdr_len);
408 ip_hdr = payload - hdr_len;
411 l2_len = vnet_buffer (b[0])->ip.save_rewrite_length;
413 l2_hdr = payload - hdr_len;
415 /* copy l2 and ip header */
416 clib_memcpy_le32 (l2_hdr, old_ip_hdr - l2_len, l2_len);
417 clib_memcpy_le64 (ip_hdr, old_ip_hdr, ip_len);
421 ip6_header_t *ip6 = (ip6_header_t *) (ip_hdr);
422 *next_hdr_ptr = ip6->protocol;
423 ip6->protocol = IP_PROTOCOL_IPSEC_ESP;
424 ip6->payload_length =
425 clib_host_to_net_u16 (payload_len + hdr_len - l2_len -
431 ip4_header_t *ip4 = (ip4_header_t *) (ip_hdr);
432 *next_hdr_ptr = ip4->protocol;
433 len = payload_len + hdr_len - l2_len;
436 esp_update_ip4_hdr (ip4, len, /* is_transport */ 1, 1);
437 esp_fill_udp_hdr (sa0, udp, len - ip_len);
440 esp_update_ip4_hdr (ip4, len, /* is_transport */ 1, 0);
443 next[0] = ESP_ENCRYPT_NEXT_INTERFACE_OUTPUT;
447 esp->seq = clib_net_to_host_u32 (sa0->seq);
449 if (sa0->crypto_enc_op_id)
451 vnet_crypto_op_t *op;
452 vec_add2_aligned (ptd->crypto_ops, op, 1, CLIB_CACHE_LINE_BYTES);
453 vnet_crypto_op_init (op, sa0->crypto_enc_op_id);
454 op->src = op->dst = payload;
455 op->key_index = sa0->crypto_key_index;
456 op->len = payload_len - icv_sz;
457 op->user_data = b - bufs;
459 if (ipsec_sa_is_set_IS_AEAD (sa0))
462 * construct the AAD in a scratch space in front
465 op->aad = payload - hdr_len - sizeof (esp_aead_t);
467 esp_aad_fill (op, esp, sa0);
469 op->tag = payload + op->len;
472 u64 *iv = (u64 *) (payload - iv_sz);
473 nonce->salt = sa0->salt;
474 nonce->iv = *iv = clib_host_to_net_u64 (sa0->gcm_iv_counter++);
475 op->iv = (u8 *) nonce;
480 op->iv = payload - iv_sz;
481 op->flags = VNET_CRYPTO_OP_FLAG_INIT_IV;
485 if (sa0->integ_op_id)
487 vnet_crypto_op_t *op;
488 vec_add2_aligned (ptd->integ_ops, op, 1, CLIB_CACHE_LINE_BYTES);
489 vnet_crypto_op_init (op, sa0->integ_op_id);
490 op->src = payload - iv_sz - sizeof (esp_header_t);
491 op->digest = payload + payload_len - icv_sz;
492 op->key_index = sa0->integ_key_index;
493 op->digest_len = icv_sz;
494 op->len = payload_len - icv_sz + iv_sz + sizeof (esp_header_t);
495 op->user_data = b - bufs;
496 if (ipsec_sa_is_set_USE_ESN (sa0))
498 u32 seq_hi = clib_net_to_host_u32 (sa0->seq_hi);
499 clib_memcpy_fast (op->digest, &seq_hi, sizeof (seq_hi));
500 op->len += sizeof (seq_hi);
504 vlib_buffer_advance (b[0], 0LL - hdr_len);
506 current_sa_packets += 1;
507 current_sa_bytes += payload_len;
510 if (PREDICT_FALSE (b[0]->flags & VLIB_BUFFER_IS_TRACED))
512 esp_encrypt_trace_t *tr = vlib_add_trace (vm, node, b[0],
514 tr->sa_index = sa_index0;
516 tr->seq = sa0->seq - 1;
517 tr->udp_encap = ipsec_sa_is_set_UDP_ENCAP (sa0);
518 tr->crypto_alg = sa0->crypto_alg;
519 tr->integ_alg = sa0->integ_alg;
527 vlib_increment_combined_counter (&ipsec_sa_counters, thread_index,
528 current_sa_index, current_sa_packets,
530 esp_process_ops (vm, node, ptd->crypto_ops, bufs, nexts);
531 esp_process_ops (vm, node, ptd->integ_ops, bufs, nexts);
533 vlib_node_increment_counter (vm, node->node_index,
534 ESP_ENCRYPT_ERROR_RX_PKTS, frame->n_vectors);
536 vlib_buffer_enqueue_to_next (vm, node, from, nexts, frame->n_vectors);
537 return frame->n_vectors;
540 VLIB_NODE_FN (esp4_encrypt_node) (vlib_main_t * vm,
541 vlib_node_runtime_t * node,
542 vlib_frame_t * from_frame)
544 return esp_encrypt_inline (vm, node, from_frame, 0 /* is_ip6 */ , 0);
548 VLIB_REGISTER_NODE (esp4_encrypt_node) = {
549 .name = "esp4-encrypt",
550 .vector_size = sizeof (u32),
551 .format_trace = format_esp_encrypt_trace,
552 .type = VLIB_NODE_TYPE_INTERNAL,
554 .n_errors = ARRAY_LEN(esp_encrypt_error_strings),
555 .error_strings = esp_encrypt_error_strings,
557 .n_next_nodes = ESP_ENCRYPT_N_NEXT,
559 #define _(s,n) [ESP_ENCRYPT_NEXT_##s] = n,
560 foreach_esp_encrypt_next
566 VLIB_NODE_FN (esp6_encrypt_node) (vlib_main_t * vm,
567 vlib_node_runtime_t * node,
568 vlib_frame_t * from_frame)
570 return esp_encrypt_inline (vm, node, from_frame, 1 /* is_ip6 */ , 0);
574 VLIB_REGISTER_NODE (esp6_encrypt_node) = {
575 .name = "esp6-encrypt",
576 .vector_size = sizeof (u32),
577 .format_trace = format_esp_encrypt_trace,
578 .type = VLIB_NODE_TYPE_INTERNAL,
580 .n_errors = ARRAY_LEN(esp_encrypt_error_strings),
581 .error_strings = esp_encrypt_error_strings,
583 .n_next_nodes = ESP_ENCRYPT_N_NEXT,
585 #define _(s,n) [ESP_ENCRYPT_NEXT_##s] = n,
586 foreach_esp_encrypt_next
592 VLIB_NODE_FN (esp4_encrypt_tun_node) (vlib_main_t * vm,
593 vlib_node_runtime_t * node,
594 vlib_frame_t * from_frame)
596 return esp_encrypt_inline (vm, node, from_frame, 0 /* is_ip6 */ , 1);
600 VLIB_REGISTER_NODE (esp4_encrypt_tun_node) = {
601 .name = "esp4-encrypt-tun",
602 .vector_size = sizeof (u32),
603 .format_trace = format_esp_encrypt_trace,
604 .type = VLIB_NODE_TYPE_INTERNAL,
606 .n_errors = ARRAY_LEN(esp_encrypt_error_strings),
607 .error_strings = esp_encrypt_error_strings,
611 [ESP_ENCRYPT_NEXT_DROP] = "ip4-drop",
615 VNET_FEATURE_INIT (esp4_encrypt_tun_feat_node, static) =
617 .arc_name = "ip4-output",
618 .node_name = "esp4-encrypt-tun",
619 .runs_before = VNET_FEATURES ("adj-midchain-tx"),
623 VLIB_NODE_FN (esp6_encrypt_tun_node) (vlib_main_t * vm,
624 vlib_node_runtime_t * node,
625 vlib_frame_t * from_frame)
627 return esp_encrypt_inline (vm, node, from_frame, 1 /* is_ip6 */ , 1);
631 VLIB_REGISTER_NODE (esp6_encrypt_tun_node) = {
632 .name = "esp6-encrypt-tun",
633 .vector_size = sizeof (u32),
634 .format_trace = format_esp_encrypt_trace,
635 .type = VLIB_NODE_TYPE_INTERNAL,
637 .n_errors = ARRAY_LEN(esp_encrypt_error_strings),
638 .error_strings = esp_encrypt_error_strings,
642 [ESP_ENCRYPT_NEXT_DROP] = "ip6-drop",
646 VNET_FEATURE_INIT (esp6_encrypt_tun_feat_node, static) =
648 .arc_name = "ip6-output",
649 .node_name = "esp6-encrypt-tun",
650 .runs_before = VNET_FEATURES ("adj-midchain-tx"),
655 * fd.io coding-style-patch-verification: ON
658 * eval: (c-set-style "gnu")