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") \
37 _ (12, CHACHA20_POLY1305, "chacha20-poly1305")
41 #define _(v, f, s) IPSEC_CRYPTO_ALG_##f = v,
42 foreach_ipsec_crypto_alg
45 } __clib_packed ipsec_crypto_alg_t;
47 #define IPSEC_CRYPTO_ALG_IS_GCM(_alg) \
48 (((_alg == IPSEC_CRYPTO_ALG_AES_GCM_128) || \
49 (_alg == IPSEC_CRYPTO_ALG_AES_GCM_192) || \
50 (_alg == IPSEC_CRYPTO_ALG_AES_GCM_256)))
52 #define IPSEC_CRYPTO_ALG_IS_CTR(_alg) \
53 (((_alg == IPSEC_CRYPTO_ALG_AES_CTR_128) || \
54 (_alg == IPSEC_CRYPTO_ALG_AES_CTR_192) || \
55 (_alg == IPSEC_CRYPTO_ALG_AES_CTR_256)))
57 #define IPSEC_CRYPTO_ALG_CTR_AEAD_OTHERS(_alg) \
58 (_alg == IPSEC_CRYPTO_ALG_CHACHA20_POLY1305)
60 #define foreach_ipsec_integ_alg \
62 _ (1, MD5_96, "md5-96") /* RFC2403 */ \
63 _ (2, SHA1_96, "sha1-96") /* RFC2404 */ \
64 _ (3, SHA_256_96, "sha-256-96") /* draft-ietf-ipsec-ciph-sha-256-00 */ \
65 _ (4, SHA_256_128, "sha-256-128") /* RFC4868 */ \
66 _ (5, SHA_384_192, "sha-384-192") /* RFC4868 */ \
67 _ (6, SHA_512_256, "sha-512-256") /* RFC4868 */
71 #define _(v, f, s) IPSEC_INTEG_ALG_##f = v,
72 foreach_ipsec_integ_alg
75 } __clib_packed ipsec_integ_alg_t;
79 IPSEC_PROTOCOL_AH = 0,
80 IPSEC_PROTOCOL_ESP = 1
81 } __clib_packed ipsec_protocol_t;
83 #define IPSEC_KEY_MAX_LEN 128
84 typedef struct ipsec_key_t_
87 u8 data[IPSEC_KEY_MAX_LEN];
91 * Enable extended sequence numbers
93 * IPsec tunnel mode if non-zero, else transport mode
94 * IPsec tunnel mode is IPv6 if non-zero,
95 * else IPv4 tunnel only valid if is_tunnel is non-zero
96 * enable UDP encapsulation for NAT traversal
98 #define foreach_ipsec_sa_flags \
100 _ (1, USE_ESN, "esn") \
101 _ (2, USE_ANTI_REPLAY, "anti-replay") \
102 _ (4, IS_TUNNEL, "tunnel") \
103 _ (8, IS_TUNNEL_V6, "tunnel-v6") \
104 _ (16, UDP_ENCAP, "udp-encap") \
105 _ (32, IS_PROTECT, "Protect") \
106 _ (64, IS_INBOUND, "inbound") \
107 _ (128, IS_AEAD, "aead") \
108 _ (256, IS_CTR, "ctr") \
109 _ (512, IS_ASYNC, "async") \
110 _ (1024, NO_ALGO_NO_DROP, "no-algo-no-drop")
112 typedef enum ipsec_sad_flags_t_
114 #define _(v, f, s) IPSEC_SA_FLAG_##f = v,
115 foreach_ipsec_sa_flags
117 } __clib_packed ipsec_sa_flags_t;
119 STATIC_ASSERT (sizeof (ipsec_sa_flags_t) == 2, "IPSEC SA flags != 2 byte");
123 CLIB_CACHE_LINE_ALIGN_MARK (cacheline0);
126 ipsec_sa_flags_t flags;
143 vnet_crypto_key_index_t crypto_key_index;
144 vnet_crypto_key_index_t integ_key_index;
146 /* Union data shared by sync and async ops, updated when mode is
152 vnet_crypto_op_id_t crypto_enc_op_id:16;
153 vnet_crypto_op_id_t crypto_dec_op_id:16;
154 vnet_crypto_op_id_t integ_op_id:16;
159 vnet_crypto_async_op_id_t crypto_async_enc_op_id:16;
160 vnet_crypto_async_op_id_t crypto_async_dec_op_id:16;
161 vnet_crypto_key_index_t linked_key_index;
167 CLIB_CACHE_LINE_ALIGN_MARK (cacheline1);
171 ip4_header_t ip4_hdr;
172 ip6_header_t ip6_hdr;
174 udp_header_t udp_hdr;
176 /* Salt used in CTR modes (incl. GCM) - stored in network byte order */
179 ipsec_protocol_t protocol;
180 tunnel_encap_decap_flags_t tunnel_flags;
183 /* data accessed by dataplane code should be above this comment */
184 CLIB_CACHE_LINE_ALIGN_MARK (cacheline2);
186 /* Elements with u64 size multiples */
191 vnet_crypto_op_id_t crypto_enc_op_id:16;
192 vnet_crypto_op_id_t crypto_dec_op_id:16;
193 vnet_crypto_op_id_t integ_op_id:16;
202 vnet_crypto_async_op_id_t crypto_async_enc_op_id:16;
203 vnet_crypto_async_op_id_t crypto_async_dec_op_id:16;
204 vnet_crypto_key_index_t linked_key_index;
213 /* elements with u32 size */
216 vnet_crypto_alg_t integ_calg;
217 vnet_crypto_alg_t crypto_calg;
220 ipsec_crypto_alg_t crypto_alg;
221 ipsec_integ_alg_t integ_alg;
223 ipsec_key_t integ_key;
224 ipsec_key_t crypto_key;
227 STATIC_ASSERT_OFFSET_OF (ipsec_sa_t, cacheline1, CLIB_CACHE_LINE_BYTES);
228 STATIC_ASSERT_OFFSET_OF (ipsec_sa_t, cacheline2, 2 * CLIB_CACHE_LINE_BYTES);
233 extern ipsec_sa_t *ipsec_sa_pool;
236 * Ensure that the IPsec data does not overlap with the IP data in
237 * the buffer meta data
239 STATIC_ASSERT (STRUCT_OFFSET_OF (vnet_buffer_opaque_t, ipsec.sad_index) ==
240 STRUCT_OFFSET_OF (vnet_buffer_opaque_t, ip.save_protocol),
241 "IPSec data is overlapping with IP data");
245 ipsec_sa_is_set_##v (const ipsec_sa_t *sa) { \
246 return (sa->flags & IPSEC_SA_FLAG_##v); \
248 foreach_ipsec_sa_flags
252 ipsec_sa_set_##v (ipsec_sa_t *sa) { \
253 return (sa->flags |= IPSEC_SA_FLAG_##v); \
255 foreach_ipsec_sa_flags
259 ipsec_sa_unset_##v (ipsec_sa_t *sa) { \
260 return (sa->flags &= ~IPSEC_SA_FLAG_##v); \
262 foreach_ipsec_sa_flags
266 * SA packet & bytes counters
268 extern vlib_combined_counter_main_t ipsec_sa_counters;
269 extern vlib_simple_counter_main_t ipsec_sa_lost_counters;
271 extern void ipsec_mk_key (ipsec_key_t * key, const u8 * data, u8 len);
274 ipsec_sa_add_and_lock (u32 id, u32 spi, ipsec_protocol_t proto,
275 ipsec_crypto_alg_t crypto_alg, const ipsec_key_t *ck,
276 ipsec_integ_alg_t integ_alg, const ipsec_key_t *ik,
277 ipsec_sa_flags_t flags, u32 salt, u16 src_port,
278 u16 dst_port, const tunnel_t *tun, u32 *sa_out_index);
279 extern index_t ipsec_sa_find_and_lock (u32 id);
280 extern int ipsec_sa_unlock_id (u32 id);
281 extern void ipsec_sa_unlock (index_t sai);
282 extern void ipsec_sa_lock (index_t sai);
283 extern void ipsec_sa_clear (index_t sai);
284 extern void ipsec_sa_set_crypto_alg (ipsec_sa_t * sa,
285 ipsec_crypto_alg_t crypto_alg);
286 extern void ipsec_sa_set_integ_alg (ipsec_sa_t * sa,
287 ipsec_integ_alg_t integ_alg);
289 typedef walk_rc_t (*ipsec_sa_walk_cb_t) (ipsec_sa_t * sa, void *ctx);
290 extern void ipsec_sa_walk (ipsec_sa_walk_cb_t cd, void *ctx);
292 extern u8 *format_ipsec_replay_window (u8 *s, va_list *args);
293 extern u8 *format_ipsec_crypto_alg (u8 * s, va_list * args);
294 extern u8 *format_ipsec_integ_alg (u8 * s, va_list * args);
295 extern u8 *format_ipsec_sa (u8 * s, va_list * args);
296 extern u8 *format_ipsec_key (u8 * s, va_list * args);
297 extern uword unformat_ipsec_crypto_alg (unformat_input_t * input,
299 extern uword unformat_ipsec_integ_alg (unformat_input_t * input,
301 extern uword unformat_ipsec_key (unformat_input_t * input, va_list * args);
303 #define IPSEC_UDP_PORT_NONE ((u16)~0)
306 * Anti Replay definitions
309 #define IPSEC_SA_ANTI_REPLAY_WINDOW_SIZE (64)
310 #define IPSEC_SA_ANTI_REPLAY_WINDOW_MAX_INDEX (IPSEC_SA_ANTI_REPLAY_WINDOW_SIZE-1)
313 * sequence number less than the lower bound are outside of the window
314 * From RFC4303 Appendix A:
317 #define IPSEC_SA_ANTI_REPLAY_WINDOW_LOWER_BOUND(_tl) (_tl - IPSEC_SA_ANTI_REPLAY_WINDOW_SIZE + 1)
320 ipsec_sa_anti_replay_check (const ipsec_sa_t *sa, u32 seq)
322 if (ipsec_sa_is_set_USE_ANTI_REPLAY (sa) &&
323 sa->replay_window & (1ULL << (sa->seq - seq)))
331 * inputs need to be in host byte order.
333 * The function runs in two contexts. pre and post decrypt.
335 * 1 - determines if a packet is a replay - a simple check in the window
336 * 2 - returns the hi-seq number that should be used to decrypt.
338 * Checks whether the packet is a replay or falls out of window
340 * This funcion should be called even without anti-replay enabled to ensure
341 * the high sequence number is set.
344 ipsec_sa_anti_replay_and_sn_advance (const ipsec_sa_t *sa, u32 seq,
345 u32 hi_seq_used, bool post_decrypt,
348 ASSERT ((post_decrypt == false) == (hi_seq_req != 0));
350 if (!ipsec_sa_is_set_USE_ESN (sa))
353 /* no ESN, therefore the hi-seq is always 0 */
356 if (!ipsec_sa_is_set_USE_ANTI_REPLAY (sa))
359 if (PREDICT_TRUE (seq > sa->seq))
362 u32 diff = sa->seq - seq;
364 if (IPSEC_SA_ANTI_REPLAY_WINDOW_SIZE > diff)
365 return ((sa->replay_window & (1ULL << diff)) ? 1 : 0);
372 if (!ipsec_sa_is_set_USE_ANTI_REPLAY (sa))
374 /* there's no AR configured for this SA, but in order
375 * to know whether a packet has wrapped the hi ESN we need
376 * to know whether it is out of window. if we use the default
377 * lower bound then we are effectively forcing AR because
378 * out of window packets will get the increased hi seq number
379 * and will thus fail to decrypt. IOW we need a window to know
380 * if the SN has wrapped, but we don't want a window to check for
381 * anti replay. to resolve the contradiction we use a huge window.
382 * if the packet is not within 2^30 of the current SN, we'll consider
388 /* The packet's sequence number is larger that the SA's.
389 * that can't be a warp - unless we lost more than
390 * 2^32 packets ... how could we know? */
391 *hi_seq_req = sa->seq_hi;
394 /* The packet's SN is less than the SAs, so either the SN has
395 * wrapped or the SN is just old. */
396 if (sa->seq - seq > (1 << 30))
397 /* It's really really really old => it wrapped */
398 *hi_seq_req = sa->seq_hi + 1;
400 *hi_seq_req = sa->seq_hi;
405 * this is post-decrpyt and since it decrypted we accept it
409 if (PREDICT_TRUE (sa->seq >= (IPSEC_SA_ANTI_REPLAY_WINDOW_MAX_INDEX)))
412 * the last sequence number VPP recieved is more than one
413 * window size greater than zero.
414 * Case A from RFC4303 Appendix A.
416 if (seq < IPSEC_SA_ANTI_REPLAY_WINDOW_LOWER_BOUND (sa->seq))
419 * the received sequence number is lower than the lower bound
420 * of the window, this could mean either a replay packet or that
421 * the high sequence number has wrapped. if it decrypts corrently
422 * then it's the latter.
426 if (hi_seq_used == sa->seq_hi)
427 /* the high sequence number used to succesfully decrypt this
428 * packet is the same as the last-sequnence number of the SA.
429 * that means this packet did not cause a wrap.
430 * this packet is thus out of window and should be dropped */
433 /* The packet decrypted with a different high sequence number
434 * to the SA, that means it is the wrap packet and should be
440 /* pre-decrypt it might be the might that casues a wrap, we
441 * need to decrpyt to find out */
443 *hi_seq_req = sa->seq_hi + 1;
450 * the recieved sequence number greater than the low
454 *hi_seq_req = sa->seq_hi;
457 * The recieved seq number is within bounds of the window
458 * check if it's a duplicate
460 return (ipsec_sa_anti_replay_check (sa, seq));
463 * The received sequence number is greater than the window
464 * upper bound. this packet will move the window along, assuming
465 * it decrypts correctly.
473 * the last sequence number VPP recieved is within one window
474 * size of zero, i.e. 0 < TL < WINDOW_SIZE, the lower bound is thus a
475 * large sequence number.
476 * Note that the check below uses unsiged integer arthimetic, so the
477 * RHS will be a larger number.
478 * Case B from RFC4303 Appendix A.
480 if (seq < IPSEC_SA_ANTI_REPLAY_WINDOW_LOWER_BOUND (sa->seq))
483 * the sequence number is less than the lower bound.
488 * the packet is within the window upper bound.
489 * check for duplicates.
492 *hi_seq_req = sa->seq_hi;
493 return (ipsec_sa_anti_replay_check (sa, seq));
498 * the packet is less the window lower bound or greater than
499 * the higher bound, depending on how you look at it...
500 * We're assuming, given that the last sequence number received,
501 * TL < WINDOW_SIZE, that a largeer seq num is more likely to be
502 * a packet that moves the window forward, than a packet that has
503 * wrapped the high sequence again. If it were the latter then
504 * we've lost close to 2^32 packets.
507 *hi_seq_req = sa->seq_hi;
514 * the packet seq number is between the lower bound (a large nubmer)
515 * and MAX_SEQ_NUM. This is in the window since the window upper bound
517 * However, since TL is the other side of 0 to the received
518 * packet, the SA has moved on to a higher sequence number.
521 *hi_seq_req = sa->seq_hi - 1;
522 return (ipsec_sa_anti_replay_check (sa, seq));
532 ipsec_sa_anti_replay_window_shift (ipsec_sa_t *sa, u32 inc)
536 if (inc < IPSEC_SA_ANTI_REPLAY_WINDOW_SIZE)
538 if (sa->seq > IPSEC_SA_ANTI_REPLAY_WINDOW_SIZE)
541 * count how many holes there are in the portion
542 * of the window that we will right shift of the end
543 * as a result of this increments
545 u64 mask = (((u64) 1 << inc) - 1) << (BITS (u64) - inc);
546 u64 old = sa->replay_window & mask;
547 /* the number of packets we saw in this section of the window */
548 u64 seen = count_set_bits (old);
551 * the number we missed is the size of the window section
552 * minus the number we saw.
556 sa->replay_window = ((sa->replay_window) << inc) | 1;
560 /* holes in the replay window are lost packets */
561 n_lost = BITS (u64) - count_set_bits (sa->replay_window);
563 /* any sequence numbers that now fall outside the window
564 * are forever lost */
565 n_lost += inc - IPSEC_SA_ANTI_REPLAY_WINDOW_SIZE;
567 sa->replay_window = 1;
574 * Anti replay window advance
575 * inputs need to be in host byte order.
576 * This function both advances the anti-replay window and the sequence number
577 * We always need to move on the SN but the window updates are only needed
579 * However, updating the window is trivial, so we do it anyway to save
583 ipsec_sa_anti_replay_advance (ipsec_sa_t *sa, u32 thread_index, u32 seq,
589 if (ipsec_sa_is_set_USE_ESN (sa))
591 int wrap = hi_seq - sa->seq_hi;
593 if (wrap == 0 && seq > sa->seq)
596 n_lost = ipsec_sa_anti_replay_window_shift (sa, pos);
601 pos = ~seq + sa->seq + 1;
602 n_lost = ipsec_sa_anti_replay_window_shift (sa, pos);
608 pos = ~seq + sa->seq + 1;
609 sa->replay_window |= (1ULL << pos);
614 sa->replay_window |= (1ULL << pos);
622 n_lost = ipsec_sa_anti_replay_window_shift (sa, pos);
628 sa->replay_window |= (1ULL << pos);
637 * Makes choice for thread_id should be assigned.
638 * if input ~0, gets random worker_id based on unix_time_now_nsec
641 ipsec_sa_assign_thread (u32 thread_id)
643 return ((thread_id) ? thread_id
644 : (unix_time_now_nsec () % vlib_num_workers ()) + 1);
647 always_inline ipsec_sa_t *
648 ipsec_sa_get (u32 sa_index)
650 return (pool_elt_at_index (ipsec_sa_pool, sa_index));
653 #endif /* __IPSEC_SPD_SA_H__ */
656 * fd.io coding-style-patch-verification: ON
659 * eval: (c-set-style "gnu")