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>
22 #include <vnet/ipsec/ipsec.h>
23 #include <vnet/ipsec/esp.h>
24 #include <vnet/ipsec/ipsec_io.h>
26 #define foreach_esp_decrypt_next \
27 _(DROP, "error-drop") \
28 _(IP4_INPUT, "ip4-input-no-checksum") \
29 _(IP6_INPUT, "ip6-input") \
30 _(IPSEC_GRE_INPUT, "ipsec-gre-input")
32 #define _(v, s) ESP_DECRYPT_NEXT_##v,
35 foreach_esp_decrypt_next
41 #define foreach_esp_decrypt_error \
42 _(RX_PKTS, "ESP pkts received") \
43 _(NO_BUFFER, "No buffer (packed dropped)") \
44 _(DECRYPTION_FAILED, "ESP decryption failed") \
45 _(INTEG_ERROR, "Integrity check failed") \
46 _(REPLAY, "SA replayed packet") \
47 _(NOT_IP, "Not IP packet (dropped)")
52 #define _(sym,str) ESP_DECRYPT_ERROR_##sym,
53 foreach_esp_decrypt_error
56 } esp_decrypt_error_t;
58 static char *esp_decrypt_error_strings[] = {
59 #define _(sym,string) string,
60 foreach_esp_decrypt_error
66 ipsec_crypto_alg_t crypto_alg;
67 ipsec_integ_alg_t integ_alg;
68 } esp_decrypt_trace_t;
70 /* packet trace format function */
72 format_esp_decrypt_trace (u8 * s, va_list * args)
74 CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
75 CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
76 esp_decrypt_trace_t *t = va_arg (*args, esp_decrypt_trace_t *);
78 s = format (s, "esp: crypto %U integrity %U",
79 format_ipsec_crypto_alg, t->crypto_alg,
80 format_ipsec_integ_alg, t->integ_alg);
85 esp_decrypt_cbc (vlib_main_t * vm, ipsec_sa_t * sa,
86 u8 * in, u8 * out, size_t in_len, u8 * key, u8 * iv)
88 vnet_crypto_op_t _op, *op = &_op;
91 if (PREDICT_FALSE (sa->crypto_dec_op_type == VNET_CRYPTO_OP_NONE))
94 op->op = sa->crypto_dec_op_type;
101 vnet_crypto_process_ops (vm, op, 1);
105 esp_decrypt_inline (vlib_main_t * vm,
106 vlib_node_runtime_t * node, vlib_frame_t * from_frame,
109 ipsec_main_t *im = &ipsec_main;
110 u32 *from = vlib_frame_vector_args (from_frame);
111 u32 n_left_from = from_frame->n_vectors;
112 u32 new_bufs[VLIB_FRAME_SIZE];
113 vlib_buffer_t *i_bufs[VLIB_FRAME_SIZE], **ib = i_bufs;
114 vlib_buffer_t *o_bufs[VLIB_FRAME_SIZE], **ob = o_bufs;
115 u16 nexts[VLIB_FRAME_SIZE], *next = nexts;
116 u32 n_alloc, thread_index = vm->thread_index;
118 n_alloc = vlib_buffer_alloc (vm, new_bufs, n_left_from);
119 if (n_alloc != n_left_from)
121 vlib_node_increment_counter (vm, node->node_index,
122 ESP_DECRYPT_ERROR_NO_BUFFER,
123 n_left_from - n_alloc);
126 n_left_from = n_alloc;
129 vlib_get_buffers (vm, from, ib, n_left_from);
130 vlib_get_buffers (vm, new_bufs, ob, n_left_from);
132 while (n_left_from > 0)
138 ip4_header_t *ih4 = 0, *oh4 = 0;
139 ip6_header_t *ih6 = 0, *oh6 = 0;
142 next[0] = ESP_DECRYPT_NEXT_DROP;
144 esp0 = vlib_buffer_get_current (ib[0]);
145 sa_index0 = vnet_buffer (ib[0])->ipsec.sad_index;
146 sa0 = pool_elt_at_index (im->sad, sa_index0);
147 seq = clib_host_to_net_u32 (esp0->seq);
149 /* anti-replay check */
150 if (ipsec_sa_is_set_USE_ANTI_REPLAY (sa0))
154 if (PREDICT_TRUE (ipsec_sa_is_set_USE_EXTENDED_SEQ_NUM (sa0)))
155 rv = esp_replay_check_esn (sa0, seq);
157 rv = esp_replay_check (sa0, seq);
159 if (PREDICT_FALSE (rv))
161 u32 tmp, off = n_alloc - n_left_from;
162 /* send original packet to drop node */
164 from[off] = new_bufs[off];
166 ib[0]->error = node->errors[ESP_DECRYPT_ERROR_REPLAY];
167 next[0] = ESP_DECRYPT_NEXT_DROP;
172 vlib_increment_combined_counter
173 (&ipsec_sa_counters, thread_index, sa_index0,
174 1, ib[0]->current_length);
176 if (PREDICT_TRUE (sa0->integ_alg != IPSEC_INTEG_ALG_NONE))
179 int icv_size = sa0->integ_trunc_size;
180 clib_memset (sig, 0, sizeof (sig));
181 u8 *icv = vlib_buffer_get_current (ib[0]) + ib[0]->current_length -
183 ib[0]->current_length -= icv_size;
185 hmac_calc (vm, sa0, (u8 *) esp0, ib[0]->current_length, sig);
187 if (PREDICT_FALSE (memcmp (icv, sig, icv_size)))
189 u32 tmp, off = n_alloc - n_left_from;
190 /* send original packet to drop node */
192 from[off] = new_bufs[off];
194 ib[0]->error = node->errors[ESP_DECRYPT_ERROR_INTEG_ERROR];
195 next[0] = ESP_DECRYPT_NEXT_DROP;
200 if (PREDICT_TRUE (ipsec_sa_is_set_USE_ANTI_REPLAY (sa0)))
202 if (PREDICT_TRUE (ipsec_sa_is_set_USE_EXTENDED_SEQ_NUM (sa0)))
203 esp_replay_advance_esn (sa0, seq);
205 esp_replay_advance (sa0, seq);
208 if ((sa0->crypto_alg >= IPSEC_CRYPTO_ALG_AES_CBC_128 &&
209 sa0->crypto_alg <= IPSEC_CRYPTO_ALG_AES_CBC_256) ||
210 (sa0->crypto_alg >= IPSEC_CRYPTO_ALG_DES_CBC &&
211 sa0->crypto_alg <= IPSEC_CRYPTO_ALG_3DES_CBC))
213 const int BLOCK_SIZE = sa0->crypto_block_size;
214 const int IV_SIZE = sa0->crypto_block_size;
219 (ib[0]->current_length - sizeof (esp_header_t) -
220 IV_SIZE) / BLOCK_SIZE;
222 ob[0]->current_data = sizeof (ethernet_header_t);
225 if (PREDICT_FALSE (!ipsec_sa_is_set_IS_TUNNEL (sa0) &&
226 !ipsec_sa_is_set_IS_TUNNEL_V6 (sa0)))
232 ip_hdr_size = sizeof (ip6_header_t);
233 ih6 = (ip6_header_t *) ((u8 *) esp0 - ip_hdr_size);
234 oh6 = vlib_buffer_get_current (ob[0]);
238 ip_hdr_size = sizeof (ip4_header_t);
239 if (ipsec_sa_is_set_UDP_ENCAP (sa0))
240 ih4 = (ip4_header_t *) ((u8 *) esp0 - ip_hdr_size -
241 sizeof (udp_header_t));
243 ih4 = (ip4_header_t *) ((u8 *) esp0 - ip_hdr_size);
244 oh4 = vlib_buffer_get_current (ob[0]);
248 esp_decrypt_cbc (vm, sa0, esp0->data + IV_SIZE,
249 (u8 *) vlib_buffer_get_current (ob[0]) +
250 ip_hdr_size, BLOCK_SIZE * blocks,
251 sa0->crypto_key.data, esp0->data);
253 ob[0]->current_length = (blocks * BLOCK_SIZE) - 2 + ip_hdr_size;
254 ob[0]->flags = VLIB_BUFFER_TOTAL_LENGTH_VALID;
255 f0 = (esp_footer_t *) ((u8 *) vlib_buffer_get_current (ob[0]) +
256 ob[0]->current_length);
257 ob[0]->current_length -= f0->pad_length;
260 if (PREDICT_TRUE (tunnel_mode))
262 if (PREDICT_TRUE (f0->next_header == IP_PROTOCOL_IP_IN_IP))
264 next[0] = ESP_DECRYPT_NEXT_IP4_INPUT;
265 oh4 = vlib_buffer_get_current (ob[0]);
267 else if (f0->next_header == IP_PROTOCOL_IPV6)
268 next[0] = ESP_DECRYPT_NEXT_IP6_INPUT;
271 vlib_node_increment_counter (vm, node->node_index,
272 ESP_DECRYPT_ERROR_DECRYPTION_FAILED,
281 u32 len = vlib_buffer_length_in_chain (vm, ob[0]);
284 next[0] = ESP_DECRYPT_NEXT_IP6_INPUT;
285 oh6->ip_version_traffic_class_and_flow_label =
286 ih6->ip_version_traffic_class_and_flow_label;
287 oh6->protocol = f0->next_header;
288 oh6->hop_limit = ih6->hop_limit;
289 oh6->src_address.as_u64[0] = ih6->src_address.as_u64[0];
290 oh6->src_address.as_u64[1] = ih6->src_address.as_u64[1];
291 oh6->dst_address.as_u64[0] = ih6->dst_address.as_u64[0];
292 oh6->dst_address.as_u64[1] = ih6->dst_address.as_u64[1];
293 len -= sizeof (ip6_header_t);
294 oh6->payload_length = clib_host_to_net_u16 (len);
298 next[0] = ESP_DECRYPT_NEXT_IP4_INPUT;
299 oh4->ip_version_and_header_length = 0x45;
301 oh4->fragment_id = 0;
302 oh4->flags_and_fragment_offset = 0;
304 oh4->protocol = f0->next_header;
305 oh4->src_address.as_u32 = ih4->src_address.as_u32;
306 oh4->dst_address.as_u32 = ih4->dst_address.as_u32;
307 oh4->length = clib_host_to_net_u16 (len);
308 oh4->checksum = ip4_header_checksum (oh4);
312 /* for IPSec-GRE tunnel next node is ipsec-gre-input */
314 ((vnet_buffer (ib[0])->ipsec.flags) &
315 IPSEC_FLAG_IPSEC_GRE_TUNNEL))
316 next[0] = ESP_DECRYPT_NEXT_IPSEC_GRE_INPUT;
318 vnet_buffer (ob[0])->sw_if_index[VLIB_TX] = (u32) ~ 0;
319 vnet_buffer (ob[0])->sw_if_index[VLIB_RX] =
320 vnet_buffer (ib[0])->sw_if_index[VLIB_RX];
324 if (PREDICT_FALSE (ib[0]->flags & VLIB_BUFFER_IS_TRACED))
328 ob[0]->flags |= VLIB_BUFFER_IS_TRACED;
329 ob[0]->trace_index = ib[0]->trace_index;
330 esp_decrypt_trace_t *tr =
331 vlib_add_trace (vm, node, ob[0], sizeof (*tr));
332 tr->crypto_alg = sa0->crypto_alg;
333 tr->integ_alg = sa0->integ_alg;
344 vlib_node_increment_counter (vm, node->node_index,
345 ESP_DECRYPT_ERROR_RX_PKTS, n_alloc);
347 vlib_buffer_enqueue_to_next (vm, node, new_bufs, nexts, n_alloc);
349 vlib_buffer_free (vm, from, from_frame->n_vectors);
353 VLIB_NODE_FN (esp4_decrypt_node) (vlib_main_t * vm,
354 vlib_node_runtime_t * node,
355 vlib_frame_t * from_frame)
357 return esp_decrypt_inline (vm, node, from_frame, 0 /* is_ip6 */ );
361 VLIB_REGISTER_NODE (esp4_decrypt_node) = {
362 .name = "esp4-decrypt",
363 .vector_size = sizeof (u32),
364 .format_trace = format_esp_decrypt_trace,
365 .type = VLIB_NODE_TYPE_INTERNAL,
367 .n_errors = ARRAY_LEN(esp_decrypt_error_strings),
368 .error_strings = esp_decrypt_error_strings,
370 .n_next_nodes = ESP_DECRYPT_N_NEXT,
372 #define _(s,n) [ESP_DECRYPT_NEXT_##s] = n,
373 foreach_esp_decrypt_next
379 VLIB_NODE_FN (esp6_decrypt_node) (vlib_main_t * vm,
380 vlib_node_runtime_t * node,
381 vlib_frame_t * from_frame)
383 return esp_decrypt_inline (vm, node, from_frame, 1 /* is_ip6 */ );
387 VLIB_REGISTER_NODE (esp6_decrypt_node) = {
388 .name = "esp6-decrypt",
389 .vector_size = sizeof (u32),
390 .format_trace = format_esp_decrypt_trace,
391 .type = VLIB_NODE_TYPE_INTERNAL,
393 .n_errors = ARRAY_LEN(esp_decrypt_error_strings),
394 .error_strings = esp_decrypt_error_strings,
396 .n_next_nodes = ESP_DECRYPT_N_NEXT,
398 #define _(s,n) [ESP_DECRYPT_NEXT_##s] = n,
399 foreach_esp_decrypt_next
406 * fd.io coding-style-patch-verification: ON
409 * eval: (c-set-style "gnu")