2 * Copyright (c) 2015 Cisco and/or its affiliates.
3 * Licensed under the Apache License, Version 2.0 (the "License");
4 * you may not use this file except in compliance with the License.
5 * You may obtain a copy of the License at:
7 * http://www.apache.org/licenses/LICENSE-2.0
9 * Unless required by applicable law or agreed to in writing, software
10 * distributed under the License is distributed on an "AS IS" BASIS,
11 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 * See the License for the specific language governing permissions and
13 * limitations under the License.
15 #ifndef __IPSEC_SPD_SA_H__
16 #define __IPSEC_SPD_SA_H__
18 #include <vlib/vlib.h>
19 #include <vnet/crypto/crypto.h>
20 #include <vnet/ip/ip.h>
21 #include <vnet/fib/fib_node.h>
22 #include <vnet/tunnel/tunnel.h>
24 #define foreach_ipsec_crypto_alg \
26 _ (1, AES_CBC_128, "aes-cbc-128") \
27 _ (2, AES_CBC_192, "aes-cbc-192") \
28 _ (3, AES_CBC_256, "aes-cbc-256") \
29 _ (4, AES_CTR_128, "aes-ctr-128") \
30 _ (5, AES_CTR_192, "aes-ctr-192") \
31 _ (6, AES_CTR_256, "aes-ctr-256") \
32 _ (7, AES_GCM_128, "aes-gcm-128") \
33 _ (8, AES_GCM_192, "aes-gcm-192") \
34 _ (9, AES_GCM_256, "aes-gcm-256") \
35 _ (10, DES_CBC, "des-cbc") \
36 _ (11, 3DES_CBC, "3des-cbc")
40 #define _(v, f, s) IPSEC_CRYPTO_ALG_##f = v,
41 foreach_ipsec_crypto_alg
44 } __clib_packed ipsec_crypto_alg_t;
46 #define IPSEC_CRYPTO_ALG_IS_GCM(_alg) \
47 (((_alg == IPSEC_CRYPTO_ALG_AES_GCM_128) || \
48 (_alg == IPSEC_CRYPTO_ALG_AES_GCM_192) || \
49 (_alg == IPSEC_CRYPTO_ALG_AES_GCM_256)))
51 #define IPSEC_CRYPTO_ALG_IS_CTR(_alg) \
52 (((_alg == IPSEC_CRYPTO_ALG_AES_CTR_128) || \
53 (_alg == IPSEC_CRYPTO_ALG_AES_CTR_192) || \
54 (_alg == IPSEC_CRYPTO_ALG_AES_CTR_256)))
56 #define foreach_ipsec_integ_alg \
58 _ (1, MD5_96, "md5-96") /* RFC2403 */ \
59 _ (2, SHA1_96, "sha1-96") /* RFC2404 */ \
60 _ (3, SHA_256_96, "sha-256-96") /* draft-ietf-ipsec-ciph-sha-256-00 */ \
61 _ (4, SHA_256_128, "sha-256-128") /* RFC4868 */ \
62 _ (5, SHA_384_192, "sha-384-192") /* RFC4868 */ \
63 _ (6, SHA_512_256, "sha-512-256") /* RFC4868 */
67 #define _(v, f, s) IPSEC_INTEG_ALG_##f = v,
68 foreach_ipsec_integ_alg
71 } __clib_packed ipsec_integ_alg_t;
75 IPSEC_PROTOCOL_AH = 0,
76 IPSEC_PROTOCOL_ESP = 1
77 } __clib_packed ipsec_protocol_t;
79 #define IPSEC_KEY_MAX_LEN 128
80 typedef struct ipsec_key_t_
83 u8 data[IPSEC_KEY_MAX_LEN];
87 * Enable extended sequence numbers
89 * IPsec tunnel mode if non-zero, else transport mode
90 * IPsec tunnel mode is IPv6 if non-zero,
91 * else IPv4 tunnel only valid if is_tunnel is non-zero
92 * enable UDP encapsulation for NAT traversal
94 #define foreach_ipsec_sa_flags \
96 _ (1, USE_ESN, "esn") \
97 _ (2, USE_ANTI_REPLAY, "anti-replay") \
98 _ (4, IS_TUNNEL, "tunnel") \
99 _ (8, IS_TUNNEL_V6, "tunnel-v6") \
100 _ (16, UDP_ENCAP, "udp-encap") \
101 _ (32, IS_PROTECT, "Protect") \
102 _ (64, IS_INBOUND, "inbound") \
103 _ (128, IS_AEAD, "aead") \
104 _ (256, IS_CTR, "ctr") \
105 _ (512, IS_ASYNC, "async")
107 typedef enum ipsec_sad_flags_t_
109 #define _(v, f, s) IPSEC_SA_FLAG_##f = v,
110 foreach_ipsec_sa_flags
112 } __clib_packed ipsec_sa_flags_t;
114 STATIC_ASSERT (sizeof (ipsec_sa_flags_t) == 2, "IPSEC SA flags != 2 byte");
118 CLIB_CACHE_LINE_ALIGN_MARK (cacheline0);
121 ipsec_sa_flags_t flags;
138 vnet_crypto_key_index_t crypto_key_index;
139 vnet_crypto_key_index_t integ_key_index;
141 /* Union data shared by sync and async ops, updated when mode is
147 vnet_crypto_op_id_t crypto_enc_op_id:16;
148 vnet_crypto_op_id_t crypto_dec_op_id:16;
149 vnet_crypto_op_id_t integ_op_id:16;
154 vnet_crypto_async_op_id_t crypto_async_enc_op_id:16;
155 vnet_crypto_async_op_id_t crypto_async_dec_op_id:16;
156 vnet_crypto_key_index_t linked_key_index;
162 CLIB_CACHE_LINE_ALIGN_MARK (cacheline1);
166 ip4_header_t ip4_hdr;
167 ip6_header_t ip6_hdr;
169 udp_header_t udp_hdr;
171 /* Salt used in CTR modes (incl. GCM) - stored in network byte order */
174 ipsec_protocol_t protocol;
175 tunnel_encap_decap_flags_t tunnel_flags;
178 /* data accessed by dataplane code should be above this comment */
179 CLIB_CACHE_LINE_ALIGN_MARK (cacheline2);
181 /* Elements with u64 size multiples */
186 vnet_crypto_op_id_t crypto_enc_op_id:16;
187 vnet_crypto_op_id_t crypto_dec_op_id:16;
188 vnet_crypto_op_id_t integ_op_id:16;
197 vnet_crypto_async_op_id_t crypto_async_enc_op_id:16;
198 vnet_crypto_async_op_id_t crypto_async_dec_op_id:16;
199 vnet_crypto_key_index_t linked_key_index;
208 /* elements with u32 size */
211 vnet_crypto_alg_t integ_calg;
212 vnet_crypto_alg_t crypto_calg;
215 ipsec_crypto_alg_t crypto_alg;
216 ipsec_integ_alg_t integ_alg;
218 ipsec_key_t integ_key;
219 ipsec_key_t crypto_key;
222 STATIC_ASSERT_OFFSET_OF (ipsec_sa_t, cacheline1, CLIB_CACHE_LINE_BYTES);
223 STATIC_ASSERT_OFFSET_OF (ipsec_sa_t, cacheline2, 2 * CLIB_CACHE_LINE_BYTES);
228 extern ipsec_sa_t *ipsec_sa_pool;
231 * Ensure that the IPsec data does not overlap with the IP data in
232 * the buffer meta data
234 STATIC_ASSERT (STRUCT_OFFSET_OF (vnet_buffer_opaque_t, ipsec.sad_index) ==
235 STRUCT_OFFSET_OF (vnet_buffer_opaque_t, ip.save_protocol),
236 "IPSec data is overlapping with IP data");
240 ipsec_sa_is_set_##v (const ipsec_sa_t *sa) { \
241 return (sa->flags & IPSEC_SA_FLAG_##v); \
243 foreach_ipsec_sa_flags
247 ipsec_sa_set_##v (ipsec_sa_t *sa) { \
248 return (sa->flags |= IPSEC_SA_FLAG_##v); \
250 foreach_ipsec_sa_flags
254 ipsec_sa_unset_##v (ipsec_sa_t *sa) { \
255 return (sa->flags &= ~IPSEC_SA_FLAG_##v); \
257 foreach_ipsec_sa_flags
261 * SA packet & bytes counters
263 extern vlib_combined_counter_main_t ipsec_sa_counters;
265 extern void ipsec_mk_key (ipsec_key_t * key, const u8 * data, u8 len);
268 ipsec_sa_add_and_lock (u32 id, u32 spi, ipsec_protocol_t proto,
269 ipsec_crypto_alg_t crypto_alg, const ipsec_key_t *ck,
270 ipsec_integ_alg_t integ_alg, const ipsec_key_t *ik,
271 ipsec_sa_flags_t flags, u32 salt, u16 src_port,
272 u16 dst_port, const tunnel_t *tun, u32 *sa_out_index);
273 extern index_t ipsec_sa_find_and_lock (u32 id);
274 extern int ipsec_sa_unlock_id (u32 id);
275 extern void ipsec_sa_unlock (index_t sai);
276 extern void ipsec_sa_lock (index_t sai);
277 extern void ipsec_sa_clear (index_t sai);
278 extern void ipsec_sa_set_crypto_alg (ipsec_sa_t * sa,
279 ipsec_crypto_alg_t crypto_alg);
280 extern void ipsec_sa_set_integ_alg (ipsec_sa_t * sa,
281 ipsec_integ_alg_t integ_alg);
283 typedef walk_rc_t (*ipsec_sa_walk_cb_t) (ipsec_sa_t * sa, void *ctx);
284 extern void ipsec_sa_walk (ipsec_sa_walk_cb_t cd, void *ctx);
286 extern u8 *format_ipsec_replay_window (u8 *s, va_list *args);
287 extern u8 *format_ipsec_crypto_alg (u8 * s, va_list * args);
288 extern u8 *format_ipsec_integ_alg (u8 * s, va_list * args);
289 extern u8 *format_ipsec_sa (u8 * s, va_list * args);
290 extern u8 *format_ipsec_key (u8 * s, va_list * args);
291 extern uword unformat_ipsec_crypto_alg (unformat_input_t * input,
293 extern uword unformat_ipsec_integ_alg (unformat_input_t * input,
295 extern uword unformat_ipsec_key (unformat_input_t * input, va_list * args);
297 #define IPSEC_UDP_PORT_NONE ((u16)~0)
300 * Anti Replay definitions
303 #define IPSEC_SA_ANTI_REPLAY_WINDOW_SIZE (64)
304 #define IPSEC_SA_ANTI_REPLAY_WINDOW_MAX_INDEX (IPSEC_SA_ANTI_REPLAY_WINDOW_SIZE-1)
307 * sequence number less than the lower bound are outside of the window
308 * From RFC4303 Appendix A:
311 #define IPSEC_SA_ANTI_REPLAY_WINDOW_LOWER_BOUND(_tl) (_tl - IPSEC_SA_ANTI_REPLAY_WINDOW_SIZE + 1)
314 ipsec_sa_anti_replay_check (const ipsec_sa_t *sa, u32 seq)
316 if (ipsec_sa_is_set_USE_ANTI_REPLAY (sa) &&
317 sa->replay_window & (1ULL << (sa->seq - seq)))
325 * inputs need to be in host byte order.
327 * The function runs in two contexts. pre and post decrypt.
329 * 1 - determines if a packet is a replay - a simple check in the window
330 * 2 - returns the hi-seq number that should be used to decrypt.
332 * Checks whether the packet is a replay or falls out of window
334 * This funcion should be called even without anti-replay enabled to ensure
335 * the high sequence number is set.
338 ipsec_sa_anti_replay_and_sn_advance (const ipsec_sa_t *sa, u32 seq,
339 u32 hi_seq_used, bool post_decrypt,
342 ASSERT ((post_decrypt == false) == (hi_seq_req != 0));
344 if (!ipsec_sa_is_set_USE_ESN (sa))
347 /* no ESN, therefore the hi-seq is always 0 */
350 if (!ipsec_sa_is_set_USE_ANTI_REPLAY (sa))
353 if (PREDICT_TRUE (seq > sa->seq))
356 u32 diff = sa->seq - seq;
358 if (IPSEC_SA_ANTI_REPLAY_WINDOW_SIZE > diff)
359 return ((sa->replay_window & (1ULL << diff)) ? 1 : 0);
366 if (!ipsec_sa_is_set_USE_ANTI_REPLAY (sa))
368 /* there's no AR configured for this SA, but in order
369 * to know whether a packet has wrapped the hi ESN we need
370 * to know whether it is out of window. if we use the default
371 * lower bound then we are effectively forcing AR because
372 * out of window packets will get the increased hi seq number
373 * and will thus fail to decrypt. IOW we need a window to know
374 * if the SN has wrapped, but we don't want a window to check for
375 * anti replay. to resolve the contradiction we use a huge window.
376 * if the packet is not within 2^30 of the current SN, we'll consider
382 /* The packet's sequence number is larger that the SA's.
383 * that can't be a warp - unless we lost more than
384 * 2^32 packets ... how could we know? */
385 *hi_seq_req = sa->seq_hi;
388 /* The packet's SN is less than the SAs, so either the SN has
389 * wrapped or the SN is just old. */
390 if (sa->seq - seq > (1 << 30))
391 /* It's really really really old => it wrapped */
392 *hi_seq_req = sa->seq_hi + 1;
394 *hi_seq_req = sa->seq_hi;
399 * this is post-decrpyt and since it decrypted we accept it
403 if (PREDICT_TRUE (sa->seq >= (IPSEC_SA_ANTI_REPLAY_WINDOW_MAX_INDEX)))
406 * the last sequence number VPP recieved is more than one
407 * window size greater than zero.
408 * Case A from RFC4303 Appendix A.
410 if (seq < IPSEC_SA_ANTI_REPLAY_WINDOW_LOWER_BOUND (sa->seq))
413 * the received sequence number is lower than the lower bound
414 * of the window, this could mean either a replay packet or that
415 * the high sequence number has wrapped. if it decrypts corrently
416 * then it's the latter.
420 if (hi_seq_used == sa->seq_hi)
421 /* the high sequence number used to succesfully decrypt this
422 * packet is the same as the last-sequnence number of the SA.
423 * that means this packet did not cause a wrap.
424 * this packet is thus out of window and should be dropped */
427 /* The packet decrypted with a different high sequence number
428 * to the SA, that means it is the wrap packet and should be
434 /* pre-decrypt it might be the might that casues a wrap, we
435 * need to decrpyt to find out */
437 *hi_seq_req = sa->seq_hi + 1;
444 * the recieved sequence number greater than the low
448 *hi_seq_req = sa->seq_hi;
451 * The recieved seq number is within bounds of the window
452 * check if it's a duplicate
454 return (ipsec_sa_anti_replay_check (sa, seq));
457 * The received sequence number is greater than the window
458 * upper bound. this packet will move the window along, assuming
459 * it decrypts correctly.
467 * the last sequence number VPP recieved is within one window
468 * size of zero, i.e. 0 < TL < WINDOW_SIZE, the lower bound is thus a
469 * large sequence number.
470 * Note that the check below uses unsiged integer arthimetic, so the
471 * RHS will be a larger number.
472 * Case B from RFC4303 Appendix A.
474 if (seq < IPSEC_SA_ANTI_REPLAY_WINDOW_LOWER_BOUND (sa->seq))
477 * the sequence number is less than the lower bound.
482 * the packet is within the window upper bound.
483 * check for duplicates.
486 *hi_seq_req = sa->seq_hi;
487 return (ipsec_sa_anti_replay_check (sa, seq));
492 * the packet is less the window lower bound or greater than
493 * the higher bound, depending on how you look at it...
494 * We're assuming, given that the last sequence number received,
495 * TL < WINDOW_SIZE, that a largeer seq num is more likely to be
496 * a packet that moves the window forward, than a packet that has
497 * wrapped the high sequence again. If it were the latter then
498 * we've lost close to 2^32 packets.
501 *hi_seq_req = sa->seq_hi;
508 * the packet seq number is between the lower bound (a large nubmer)
509 * and MAX_SEQ_NUM. This is in the window since the window upper bound
511 * However, since TL is the other side of 0 to the received
512 * packet, the SA has moved on to a higher sequence number.
515 *hi_seq_req = sa->seq_hi - 1;
516 return (ipsec_sa_anti_replay_check (sa, seq));
526 * Anti replay window advance
527 * inputs need to be in host byte order.
528 * This function both advances the anti-replay window and the sequence number
529 * We always need to move on the SN but the window updates are only needed
531 * However, updating the window is trivial, so we do it anyway to save
535 ipsec_sa_anti_replay_advance (ipsec_sa_t *sa, u32 seq, u32 hi_seq)
539 if (ipsec_sa_is_set_USE_ESN (sa))
541 int wrap = hi_seq - sa->seq_hi;
543 if (wrap == 0 && seq > sa->seq)
546 if (pos < IPSEC_SA_ANTI_REPLAY_WINDOW_SIZE)
547 sa->replay_window = ((sa->replay_window) << pos) | 1;
549 sa->replay_window = 1;
554 pos = ~seq + sa->seq + 1;
555 if (pos < IPSEC_SA_ANTI_REPLAY_WINDOW_SIZE)
556 sa->replay_window = ((sa->replay_window) << pos) | 1;
558 sa->replay_window = 1;
564 pos = ~seq + sa->seq + 1;
565 sa->replay_window |= (1ULL << pos);
570 sa->replay_window |= (1ULL << pos);
578 if (pos < IPSEC_SA_ANTI_REPLAY_WINDOW_SIZE)
579 sa->replay_window = ((sa->replay_window) << pos) | 1;
581 sa->replay_window = 1;
587 sa->replay_window |= (1ULL << pos);
594 * Makes choice for thread_id should be assigned.
595 * if input ~0, gets random worker_id based on unix_time_now_nsec
598 ipsec_sa_assign_thread (u32 thread_id)
600 return ((thread_id) ? thread_id
601 : (unix_time_now_nsec () % vlib_num_workers ()) + 1);
604 always_inline ipsec_sa_t *
605 ipsec_sa_get (u32 sa_index)
607 return (pool_elt_at_index (ipsec_sa_pool, sa_index));
610 #endif /* __IPSEC_SPD_SA_H__ */
613 * fd.io coding-style-patch-verification: ON
616 * eval: (c-set-style "gnu")