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 *);
83 "esp: sa-index %d spi %u (0x%08x) seq %u crypto %U integrity %U%s",
84 t->sa_index, t->spi, t->spi, t->seq, format_ipsec_crypto_alg,
85 t->crypto_alg, format_ipsec_integ_alg, t->integ_alg,
86 t->udp_encap ? " udp-encap-enabled" : "");
90 /* pad packet in input buffer */
91 static_always_inline u8 *
92 esp_add_footer_and_icv (vlib_buffer_t * b, u8 block_size, u8 icv_sz)
94 static const u8 pad_data[ESP_MAX_BLOCK_SIZE] = {
95 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08,
96 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x00, 0x00,
99 u16 min_length = b->current_length + sizeof (esp_footer_t);
100 u16 new_length = round_pow2 (min_length, block_size);
101 u8 pad_bytes = new_length - min_length;
102 esp_footer_t *f = (esp_footer_t *) (vlib_buffer_get_current (b) +
103 new_length - sizeof (esp_footer_t));
106 clib_memcpy_fast ((u8 *) f - pad_bytes, pad_data, ESP_MAX_BLOCK_SIZE);
108 f->pad_length = pad_bytes;
109 b->current_length = new_length + icv_sz;
110 return &f->next_header;
113 static_always_inline void
114 esp_update_ip4_hdr (ip4_header_t * ip4, u16 len, int is_transport, int is_udp)
119 len = clib_net_to_host_u16 (len);
120 old_len = ip4->length;
124 u8 prot = is_udp ? IP_PROTOCOL_UDP : IP_PROTOCOL_IPSEC_ESP;
126 sum = ip_csum_update (ip4->checksum, ip4->protocol,
127 prot, ip4_header_t, protocol);
128 ip4->protocol = prot;
130 sum = ip_csum_update (sum, old_len, len, ip4_header_t, length);
133 sum = ip_csum_update (ip4->checksum, old_len, len, ip4_header_t, length);
136 ip4->checksum = ip_csum_fold (sum);
139 static_always_inline void
140 esp_fill_udp_hdr (ipsec_sa_t * sa, udp_header_t * udp, u16 len)
142 clib_memcpy_fast (udp, &sa->udp_hdr, sizeof (udp_header_t));
143 udp->length = clib_net_to_host_u16 (len);
146 static_always_inline u8
147 ext_hdr_is_pre_esp (u8 nexthdr)
149 #ifdef CLIB_HAVE_VEC128
150 static const u8x16 ext_hdr_types = {
151 IP_PROTOCOL_IP6_HOP_BY_HOP_OPTIONS,
152 IP_PROTOCOL_IPV6_ROUTE,
153 IP_PROTOCOL_IPV6_FRAGMENTATION,
156 return !u8x16_is_all_zero (ext_hdr_types == u8x16_splat (nexthdr));
158 return ((nexthdr ^ IP_PROTOCOL_IP6_HOP_BY_HOP_OPTIONS) |
159 (nexthdr ^ IP_PROTOCOL_IPV6_ROUTE) |
160 (nexthdr ^ IP_PROTOCOL_IPV6_FRAGMENTATION) != 0);
164 static_always_inline u8
165 esp_get_ip6_hdr_len (ip6_header_t * ip6)
167 /* this code assumes that HbH, route and frag headers will be before
168 others, if that is not the case, they will end up encrypted */
170 u8 len = sizeof (ip6_header_t);
173 /* if next packet doesn't have ext header */
174 if (ext_hdr_is_pre_esp (ip6->protocol) == 0)
177 p = (void *) (ip6 + 1);
178 len += ip6_ext_header_len (p);
180 while (ext_hdr_is_pre_esp (p->next_hdr))
182 len += ip6_ext_header_len (p);
183 p = ip6_ext_next_header (p);
189 static_always_inline int
190 esp_trailer_icv_overflow (vlib_node_runtime_t * node, vlib_buffer_t * b,
191 u16 * next, u16 buffer_data_size)
193 if (b->current_data + b->current_length <= buffer_data_size)
196 b->current_length -= buffer_data_size - b->current_data;
197 b->error = node->errors[ESP_ENCRYPT_ERROR_NO_TRAILER_SPACE];
198 next[0] = ESP_ENCRYPT_NEXT_DROP;
202 static_always_inline void
203 esp_process_ops (vlib_main_t * vm, vlib_node_runtime_t * node,
204 vnet_crypto_op_t * ops, vlib_buffer_t * b[], u16 * nexts)
206 u32 n_fail, n_ops = vec_len (ops);
207 vnet_crypto_op_t *op = ops;
212 n_fail = n_ops - vnet_crypto_process_ops (vm, op, n_ops);
216 ASSERT (op - ops < n_ops);
218 if (op->status != VNET_CRYPTO_OP_STATUS_COMPLETED)
220 u32 bi = op->user_data;
221 b[bi]->error = node->errors[ESP_ENCRYPT_ERROR_CRYPTO_ENGINE_ERROR];
222 nexts[bi] = ESP_ENCRYPT_NEXT_DROP;
233 } __clib_packed esp_gcm_nonce_t;
235 STATIC_ASSERT_SIZEOF (esp_gcm_nonce_t, 12);
238 esp_encrypt_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
239 vlib_frame_t * frame, int is_ip6, int is_tun)
241 ipsec_main_t *im = &ipsec_main;
242 ipsec_per_thread_data_t *ptd = vec_elt_at_index (im->ptd, vm->thread_index);
243 u32 *from = vlib_frame_vector_args (frame);
244 u32 n_left = frame->n_vectors;
245 vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b = bufs;
246 u16 nexts[VLIB_FRAME_SIZE], *next = nexts;
247 esp_gcm_nonce_t nonces[VLIB_FRAME_SIZE], *nonce = nonces;
248 u32 thread_index = vm->thread_index;
249 u16 buffer_data_size = vlib_buffer_get_default_data_size (vm);
250 u32 current_sa_index = ~0, current_sa_packets = 0;
251 u32 current_sa_bytes = 0, spi = 0;
252 u8 block_sz = 0, iv_sz = 0, icv_sz = 0;
255 vlib_get_buffers (vm, from, b, n_left);
256 vec_reset_length (ptd->crypto_ops);
257 vec_reset_length (ptd->integ_ops);
264 u8 *payload, *next_hdr_ptr;
271 vlib_prefetch_buffer_header (b[2], LOAD);
272 p = vlib_buffer_get_current (b[1]);
273 CLIB_PREFETCH (p, CLIB_CACHE_LINE_BYTES, LOAD);
274 p -= CLIB_CACHE_LINE_BYTES;
275 CLIB_PREFETCH (p, CLIB_CACHE_LINE_BYTES, LOAD);
280 /* we are on a ipsec tunnel's feature arc */
282 sa_index0 = *(u32 *) vnet_feature_next_with_data (&next0, b[0],
288 sa_index0 = vnet_buffer (b[0])->ipsec.sad_index;
290 if (sa_index0 != current_sa_index)
292 if (current_sa_packets)
293 vlib_increment_combined_counter (&ipsec_sa_counters, thread_index,
297 current_sa_packets = current_sa_bytes = 0;
299 sa0 = pool_elt_at_index (im->sad, sa_index0);
300 current_sa_index = sa_index0;
301 spi = clib_net_to_host_u32 (sa0->spi);
302 block_sz = sa0->crypto_block_size;
303 icv_sz = sa0->integ_icv_size;
304 iv_sz = sa0->crypto_iv_size;
307 if (vlib_buffer_chain_linearize (vm, b[0]) != 1)
309 b[0]->error = node->errors[ESP_ENCRYPT_ERROR_CHAINED_BUFFER];
310 next[0] = ESP_ENCRYPT_NEXT_DROP;
314 if (PREDICT_FALSE (esp_seq_advance (sa0)))
316 b[0]->error = node->errors[ESP_ENCRYPT_ERROR_SEQ_CYCLED];
317 next[0] = ESP_ENCRYPT_NEXT_DROP;
324 if (ipsec_sa_is_set_IS_TUNNEL (sa0))
326 payload = vlib_buffer_get_current (b[0]);
327 next_hdr_ptr = esp_add_footer_and_icv (b[0], block_sz, icv_sz);
328 payload_len = b[0]->current_length;
330 if (esp_trailer_icv_overflow (node, b[0], next, buffer_data_size))
334 hdr_len += sizeof (*esp);
335 esp = (esp_header_t *) (payload - hdr_len);
337 /* optional UDP header */
338 if (ipsec_sa_is_set_UDP_ENCAP (sa0))
340 hdr_len += sizeof (udp_header_t);
341 esp_fill_udp_hdr (sa0, (udp_header_t *) (payload - hdr_len),
342 payload_len + hdr_len);
346 if (ipsec_sa_is_set_IS_TUNNEL_V6 (sa0))
349 u16 len = sizeof (ip6_header_t);
351 ip6 = (ip6_header_t *) (payload - hdr_len);
352 clib_memcpy_fast (ip6, &sa0->ip6_hdr, len);
353 *next_hdr_ptr = (is_ip6 ?
354 IP_PROTOCOL_IPV6 : IP_PROTOCOL_IP_IN_IP);
355 len = payload_len + hdr_len - len;
356 ip6->payload_length = clib_net_to_host_u16 (len);
361 u16 len = sizeof (ip4_header_t);
363 ip4 = (ip4_header_t *) (payload - hdr_len);
364 clib_memcpy_fast (ip4, &sa0->ip4_hdr, len);
365 *next_hdr_ptr = (is_ip6 ?
366 IP_PROTOCOL_IPV6 : IP_PROTOCOL_IP_IN_IP);
367 len = payload_len + hdr_len;
368 esp_update_ip4_hdr (ip4, len, /* is_transport */ 0, 0);
374 next[0] = dpo->dpoi_next_node;
375 vnet_buffer (b[0])->ip.adj_index[VLIB_TX] = dpo->dpoi_index;
378 else /* transport mode */
380 u8 *l2_hdr, l2_len, *ip_hdr, ip_len;
381 udp_header_t *udp = 0;
382 u8 *old_ip_hdr = vlib_buffer_get_current (b[0]);
385 esp_get_ip6_hdr_len ((ip6_header_t *) old_ip_hdr) :
386 ip4_header_bytes ((ip4_header_t *) old_ip_hdr);
388 vlib_buffer_advance (b[0], ip_len);
389 payload = vlib_buffer_get_current (b[0]);
390 next_hdr_ptr = esp_add_footer_and_icv (b[0], block_sz, icv_sz);
391 payload_len = b[0]->current_length;
393 if (esp_trailer_icv_overflow (node, b[0], next, buffer_data_size))
397 hdr_len += sizeof (*esp);
398 esp = (esp_header_t *) (payload - hdr_len);
400 /* optional UDP header */
401 if (ipsec_sa_is_set_UDP_ENCAP (sa0))
403 hdr_len += sizeof (udp_header_t);
404 udp = (udp_header_t *) (payload - hdr_len);
409 ip_hdr = payload - hdr_len;
414 l2_len = vnet_buffer (b[0])->ip.save_rewrite_length;
416 l2_hdr = payload - hdr_len;
418 /* copy l2 and ip header */
419 clib_memcpy_le32 (l2_hdr, old_ip_hdr - l2_len, l2_len);
424 clib_memcpy_le64 (ip_hdr, old_ip_hdr, ip_len);
428 ip6_header_t *ip6 = (ip6_header_t *) (ip_hdr);
429 *next_hdr_ptr = ip6->protocol;
430 ip6->protocol = IP_PROTOCOL_IPSEC_ESP;
431 ip6->payload_length =
432 clib_host_to_net_u16 (payload_len + hdr_len - l2_len -
438 ip4_header_t *ip4 = (ip4_header_t *) (ip_hdr);
439 *next_hdr_ptr = ip4->protocol;
440 len = payload_len + hdr_len - l2_len;
443 esp_update_ip4_hdr (ip4, len, /* is_transport */ 1, 1);
444 esp_fill_udp_hdr (sa0, udp, len - ip_len);
447 esp_update_ip4_hdr (ip4, len, /* is_transport */ 1, 0);
451 next[0] = ESP_ENCRYPT_NEXT_INTERFACE_OUTPUT;
455 esp->seq = clib_net_to_host_u32 (sa0->seq);
457 if (sa0->crypto_enc_op_id)
459 vnet_crypto_op_t *op;
460 vec_add2_aligned (ptd->crypto_ops, op, 1, CLIB_CACHE_LINE_BYTES);
461 vnet_crypto_op_init (op, sa0->crypto_enc_op_id);
462 op->src = op->dst = payload;
463 op->key_index = sa0->crypto_key_index;
464 op->len = payload_len - icv_sz;
465 op->user_data = b - bufs;
467 if (ipsec_sa_is_set_IS_AEAD (sa0))
470 * construct the AAD in a scratch space in front
473 op->aad = payload - hdr_len - sizeof (esp_aead_t);
475 esp_aad_fill (op, esp, sa0);
477 op->tag = payload + op->len;
480 u64 *iv = (u64 *) (payload - iv_sz);
481 nonce->salt = sa0->salt;
482 nonce->iv = *iv = clib_host_to_net_u64 (sa0->gcm_iv_counter++);
483 op->iv = (u8 *) nonce;
488 op->iv = payload - iv_sz;
489 op->flags = VNET_CRYPTO_OP_FLAG_INIT_IV;
493 if (sa0->integ_op_id)
495 vnet_crypto_op_t *op;
496 vec_add2_aligned (ptd->integ_ops, op, 1, CLIB_CACHE_LINE_BYTES);
497 vnet_crypto_op_init (op, sa0->integ_op_id);
498 op->src = payload - iv_sz - sizeof (esp_header_t);
499 op->digest = payload + payload_len - icv_sz;
500 op->key_index = sa0->integ_key_index;
501 op->digest_len = icv_sz;
502 op->len = payload_len - icv_sz + iv_sz + sizeof (esp_header_t);
503 op->user_data = b - bufs;
504 if (ipsec_sa_is_set_USE_ESN (sa0))
506 u32 seq_hi = clib_net_to_host_u32 (sa0->seq_hi);
507 clib_memcpy_fast (op->digest, &seq_hi, sizeof (seq_hi));
508 op->len += sizeof (seq_hi);
512 vlib_buffer_advance (b[0], 0LL - hdr_len);
514 current_sa_packets += 1;
515 current_sa_bytes += payload_len;
518 if (PREDICT_FALSE (b[0]->flags & VLIB_BUFFER_IS_TRACED))
520 esp_encrypt_trace_t *tr = vlib_add_trace (vm, node, b[0],
522 tr->sa_index = sa_index0;
524 tr->seq = sa0->seq - 1;
525 tr->udp_encap = ipsec_sa_is_set_UDP_ENCAP (sa0);
526 tr->crypto_alg = sa0->crypto_alg;
527 tr->integ_alg = sa0->integ_alg;
535 vlib_increment_combined_counter (&ipsec_sa_counters, thread_index,
536 current_sa_index, current_sa_packets,
538 esp_process_ops (vm, node, ptd->crypto_ops, bufs, nexts);
539 esp_process_ops (vm, node, ptd->integ_ops, bufs, nexts);
541 vlib_node_increment_counter (vm, node->node_index,
542 ESP_ENCRYPT_ERROR_RX_PKTS, frame->n_vectors);
544 vlib_buffer_enqueue_to_next (vm, node, from, nexts, frame->n_vectors);
545 return frame->n_vectors;
548 VLIB_NODE_FN (esp4_encrypt_node) (vlib_main_t * vm,
549 vlib_node_runtime_t * node,
550 vlib_frame_t * from_frame)
552 return esp_encrypt_inline (vm, node, from_frame, 0 /* is_ip6 */ , 0);
556 VLIB_REGISTER_NODE (esp4_encrypt_node) = {
557 .name = "esp4-encrypt",
558 .vector_size = sizeof (u32),
559 .format_trace = format_esp_encrypt_trace,
560 .type = VLIB_NODE_TYPE_INTERNAL,
562 .n_errors = ARRAY_LEN(esp_encrypt_error_strings),
563 .error_strings = esp_encrypt_error_strings,
565 .n_next_nodes = ESP_ENCRYPT_N_NEXT,
567 #define _(s,n) [ESP_ENCRYPT_NEXT_##s] = n,
568 foreach_esp_encrypt_next
574 VLIB_NODE_FN (esp6_encrypt_node) (vlib_main_t * vm,
575 vlib_node_runtime_t * node,
576 vlib_frame_t * from_frame)
578 return esp_encrypt_inline (vm, node, from_frame, 1 /* is_ip6 */ , 0);
582 VLIB_REGISTER_NODE (esp6_encrypt_node) = {
583 .name = "esp6-encrypt",
584 .vector_size = sizeof (u32),
585 .format_trace = format_esp_encrypt_trace,
586 .type = VLIB_NODE_TYPE_INTERNAL,
588 .n_errors = ARRAY_LEN(esp_encrypt_error_strings),
589 .error_strings = esp_encrypt_error_strings,
591 .n_next_nodes = ESP_ENCRYPT_N_NEXT,
593 #define _(s,n) [ESP_ENCRYPT_NEXT_##s] = n,
594 foreach_esp_encrypt_next
600 VLIB_NODE_FN (esp4_encrypt_tun_node) (vlib_main_t * vm,
601 vlib_node_runtime_t * node,
602 vlib_frame_t * from_frame)
604 return esp_encrypt_inline (vm, node, from_frame, 0 /* is_ip6 */ , 1);
608 VLIB_REGISTER_NODE (esp4_encrypt_tun_node) = {
609 .name = "esp4-encrypt-tun",
610 .vector_size = sizeof (u32),
611 .format_trace = format_esp_encrypt_trace,
612 .type = VLIB_NODE_TYPE_INTERNAL,
614 .n_errors = ARRAY_LEN(esp_encrypt_error_strings),
615 .error_strings = esp_encrypt_error_strings,
619 [ESP_ENCRYPT_NEXT_DROP] = "ip4-drop",
623 VNET_FEATURE_INIT (esp4_encrypt_tun_feat_node, static) =
625 .arc_name = "ip4-output",
626 .node_name = "esp4-encrypt-tun",
627 .runs_before = VNET_FEATURES ("adj-midchain-tx"),
630 VNET_FEATURE_INIT (esp4_ethernet_encrypt_tun_feat_node, static) =
632 .arc_name = "ethernet-output",
633 .node_name = "esp4-encrypt-tun",
634 .runs_before = VNET_FEATURES ("adj-midchain-tx", "adj-midchain-tx-no-count"),
638 VLIB_NODE_FN (esp6_encrypt_tun_node) (vlib_main_t * vm,
639 vlib_node_runtime_t * node,
640 vlib_frame_t * from_frame)
642 return esp_encrypt_inline (vm, node, from_frame, 1 /* is_ip6 */ , 1);
646 VLIB_REGISTER_NODE (esp6_encrypt_tun_node) = {
647 .name = "esp6-encrypt-tun",
648 .vector_size = sizeof (u32),
649 .format_trace = format_esp_encrypt_trace,
650 .type = VLIB_NODE_TYPE_INTERNAL,
652 .n_errors = ARRAY_LEN(esp_encrypt_error_strings),
653 .error_strings = esp_encrypt_error_strings,
657 [ESP_ENCRYPT_NEXT_DROP] = "ip6-drop",
661 VNET_FEATURE_INIT (esp6_encrypt_tun_feat_node, static) =
663 .arc_name = "ip6-output",
664 .node_name = "esp6-encrypt-tun",
665 .runs_before = VNET_FEATURES ("adj-midchain-tx"),
670 * fd.io coding-style-patch-verification: ON
673 * eval: (c-set-style "gnu")