1 /* 2 * Copyright (c) 2016-2017, Mellanox Technologies. All rights reserved. 3 * Copyright (c) 2016-2017, Dave Watson <davejwatson@fb.com>. All rights reserved. 4 * 5 * This software is available to you under a choice of one of two 6 * licenses. You may choose to be licensed under the terms of the GNU 7 * General Public License (GPL) Version 2, available from the file 8 * COPYING in the main directory of this source tree, or the 9 * OpenIB.org BSD license below: 10 * 11 * Redistribution and use in source and binary forms, with or 12 * without modification, are permitted provided that the following 13 * conditions are met: 14 * 15 * - Redistributions of source code must retain the above 16 * copyright notice, this list of conditions and the following 17 * disclaimer. 18 * 19 * - Redistributions in binary form must reproduce the above 20 * copyright notice, this list of conditions and the following 21 * disclaimer in the documentation and/or other materials 22 * provided with the distribution. 23 * 24 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 25 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 26 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 27 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS 28 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN 29 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN 30 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE 31 * SOFTWARE. 32 */ 33 34 #ifndef _TLS_OFFLOAD_H 35 #define _TLS_OFFLOAD_H 36 37 #include <linux/types.h> 38 #include <asm/byteorder.h> 39 #include <linux/crypto.h> 40 #include <linux/socket.h> 41 #include <linux/tcp.h> 42 #include <linux/mutex.h> 43 #include <linux/netdevice.h> 44 #include <linux/rcupdate.h> 45 46 #include <net/net_namespace.h> 47 #include <net/tcp.h> 48 #include <net/strparser.h> 49 #include <crypto/aead.h> 50 #include <uapi/linux/tls.h> 51 52 struct tls_rec; 53 54 struct tls_cipher_size_desc { 55 unsigned int iv; 56 unsigned int key; 57 unsigned int salt; 58 unsigned int tag; 59 unsigned int rec_seq; 60 }; 61 62 extern const struct tls_cipher_size_desc tls_cipher_size_desc[]; 63 64 /* Maximum data size carried in a TLS record */ 65 #define TLS_MAX_PAYLOAD_SIZE ((size_t)1 << 14) 66 67 #define TLS_HEADER_SIZE 5 68 #define TLS_NONCE_OFFSET TLS_HEADER_SIZE 69 70 #define TLS_CRYPTO_INFO_READY(info) ((info)->cipher_type) 71 72 #define TLS_RECORD_TYPE_DATA 0x17 73 74 #define TLS_AAD_SPACE_SIZE 13 75 76 #define MAX_IV_SIZE 16 77 #define TLS_TAG_SIZE 16 78 #define TLS_MAX_REC_SEQ_SIZE 8 79 #define TLS_MAX_AAD_SIZE TLS_AAD_SPACE_SIZE 80 81 /* For CCM mode, the full 16-bytes of IV is made of '4' fields of given sizes. 82 * 83 * IV[16] = b0[1] || implicit nonce[4] || explicit nonce[8] || length[3] 84 * 85 * The field 'length' is encoded in field 'b0' as '(length width - 1)'. 86 * Hence b0 contains (3 - 1) = 2. 87 */ 88 #define TLS_AES_CCM_IV_B0_BYTE 2 89 #define TLS_SM4_CCM_IV_B0_BYTE 2 90 91 enum { 92 TLS_BASE, 93 TLS_SW, 94 TLS_HW, 95 TLS_HW_RECORD, 96 TLS_NUM_CONFIG, 97 }; 98 99 struct tx_work { 100 struct delayed_work work; 101 struct sock *sk; 102 }; 103 104 struct tls_sw_context_tx { 105 struct crypto_aead *aead_send; 106 struct crypto_wait async_wait; 107 struct tx_work tx_work; 108 struct tls_rec *open_rec; 109 struct list_head tx_list; 110 atomic_t encrypt_pending; 111 /* protect crypto_wait with encrypt_pending */ 112 spinlock_t encrypt_compl_lock; 113 int async_notify; 114 u8 async_capable:1; 115 116 #define BIT_TX_SCHEDULED 0 117 #define BIT_TX_CLOSING 1 118 unsigned long tx_bitmask; 119 }; 120 121 struct tls_strparser { 122 struct sock *sk; 123 124 u32 mark : 8; 125 u32 stopped : 1; 126 u32 copy_mode : 1; 127 u32 msg_ready : 1; 128 129 struct strp_msg stm; 130 131 struct sk_buff *anchor; 132 struct work_struct work; 133 }; 134 135 struct tls_sw_context_rx { 136 struct crypto_aead *aead_recv; 137 struct crypto_wait async_wait; 138 struct sk_buff_head rx_list; /* list of decrypted 'data' records */ 139 void (*saved_data_ready)(struct sock *sk); 140 141 u8 reader_present; 142 u8 async_capable:1; 143 u8 zc_capable:1; 144 u8 reader_contended:1; 145 146 struct tls_strparser strp; 147 148 atomic_t decrypt_pending; 149 /* protect crypto_wait with decrypt_pending*/ 150 spinlock_t decrypt_compl_lock; 151 struct sk_buff_head async_hold; 152 struct wait_queue_head wq; 153 }; 154 155 struct tls_record_info { 156 struct list_head list; 157 u32 end_seq; 158 int len; 159 int num_frags; 160 skb_frag_t frags[MAX_SKB_FRAGS]; 161 }; 162 163 struct tls_offload_context_tx { 164 struct crypto_aead *aead_send; 165 spinlock_t lock; /* protects records list */ 166 struct list_head records_list; 167 struct tls_record_info *open_record; 168 struct tls_record_info *retransmit_hint; 169 u64 hint_record_sn; 170 u64 unacked_record_sn; 171 172 struct scatterlist sg_tx_data[MAX_SKB_FRAGS]; 173 void (*sk_destruct)(struct sock *sk); 174 struct work_struct destruct_work; 175 struct tls_context *ctx; 176 u8 driver_state[] __aligned(8); 177 /* The TLS layer reserves room for driver specific state 178 * Currently the belief is that there is not enough 179 * driver specific state to justify another layer of indirection 180 */ 181 #define TLS_DRIVER_STATE_SIZE_TX 16 182 }; 183 184 #define TLS_OFFLOAD_CONTEXT_SIZE_TX \ 185 (sizeof(struct tls_offload_context_tx) + TLS_DRIVER_STATE_SIZE_TX) 186 187 enum tls_context_flags { 188 /* tls_device_down was called after the netdev went down, device state 189 * was released, and kTLS works in software, even though rx_conf is 190 * still TLS_HW (needed for transition). 191 */ 192 TLS_RX_DEV_DEGRADED = 0, 193 /* Unlike RX where resync is driven entirely by the core in TX only 194 * the driver knows when things went out of sync, so we need the flag 195 * to be atomic. 196 */ 197 TLS_TX_SYNC_SCHED = 1, 198 /* tls_dev_del was called for the RX side, device state was released, 199 * but tls_ctx->netdev might still be kept, because TX-side driver 200 * resources might not be released yet. Used to prevent the second 201 * tls_dev_del call in tls_device_down if it happens simultaneously. 202 */ 203 TLS_RX_DEV_CLOSED = 2, 204 }; 205 206 struct cipher_context { 207 char *iv; 208 char *rec_seq; 209 }; 210 211 union tls_crypto_context { 212 struct tls_crypto_info info; 213 union { 214 struct tls12_crypto_info_aes_gcm_128 aes_gcm_128; 215 struct tls12_crypto_info_aes_gcm_256 aes_gcm_256; 216 struct tls12_crypto_info_chacha20_poly1305 chacha20_poly1305; 217 struct tls12_crypto_info_sm4_gcm sm4_gcm; 218 struct tls12_crypto_info_sm4_ccm sm4_ccm; 219 }; 220 }; 221 222 struct tls_prot_info { 223 u16 version; 224 u16 cipher_type; 225 u16 prepend_size; 226 u16 tag_size; 227 u16 overhead_size; 228 u16 iv_size; 229 u16 salt_size; 230 u16 rec_seq_size; 231 u16 aad_size; 232 u16 tail_size; 233 }; 234 235 struct tls_context { 236 /* read-only cache line */ 237 struct tls_prot_info prot_info; 238 239 u8 tx_conf:3; 240 u8 rx_conf:3; 241 u8 zerocopy_sendfile:1; 242 u8 rx_no_pad:1; 243 244 int (*push_pending_record)(struct sock *sk, int flags); 245 void (*sk_write_space)(struct sock *sk); 246 247 void *priv_ctx_tx; 248 void *priv_ctx_rx; 249 250 struct net_device __rcu *netdev; 251 252 /* rw cache line */ 253 struct cipher_context tx; 254 struct cipher_context rx; 255 256 struct scatterlist *partially_sent_record; 257 u16 partially_sent_offset; 258 259 bool in_tcp_sendpages; 260 bool pending_open_record_frags; 261 262 struct mutex tx_lock; /* protects partially_sent_* fields and 263 * per-type TX fields 264 */ 265 unsigned long flags; 266 267 /* cache cold stuff */ 268 struct proto *sk_proto; 269 struct sock *sk; 270 271 void (*sk_destruct)(struct sock *sk); 272 273 union tls_crypto_context crypto_send; 274 union tls_crypto_context crypto_recv; 275 276 struct list_head list; 277 refcount_t refcount; 278 struct rcu_head rcu; 279 }; 280 281 enum tls_offload_ctx_dir { 282 TLS_OFFLOAD_CTX_DIR_RX, 283 TLS_OFFLOAD_CTX_DIR_TX, 284 }; 285 286 struct tlsdev_ops { 287 int (*tls_dev_add)(struct net_device *netdev, struct sock *sk, 288 enum tls_offload_ctx_dir direction, 289 struct tls_crypto_info *crypto_info, 290 u32 start_offload_tcp_sn); 291 void (*tls_dev_del)(struct net_device *netdev, 292 struct tls_context *ctx, 293 enum tls_offload_ctx_dir direction); 294 int (*tls_dev_resync)(struct net_device *netdev, 295 struct sock *sk, u32 seq, u8 *rcd_sn, 296 enum tls_offload_ctx_dir direction); 297 }; 298 299 enum tls_offload_sync_type { 300 TLS_OFFLOAD_SYNC_TYPE_DRIVER_REQ = 0, 301 TLS_OFFLOAD_SYNC_TYPE_CORE_NEXT_HINT = 1, 302 TLS_OFFLOAD_SYNC_TYPE_DRIVER_REQ_ASYNC = 2, 303 }; 304 305 #define TLS_DEVICE_RESYNC_NH_START_IVAL 2 306 #define TLS_DEVICE_RESYNC_NH_MAX_IVAL 128 307 308 #define TLS_DEVICE_RESYNC_ASYNC_LOGMAX 13 309 struct tls_offload_resync_async { 310 atomic64_t req; 311 u16 loglen; 312 u16 rcd_delta; 313 u32 log[TLS_DEVICE_RESYNC_ASYNC_LOGMAX]; 314 }; 315 316 struct tls_offload_context_rx { 317 /* sw must be the first member of tls_offload_context_rx */ 318 struct tls_sw_context_rx sw; 319 enum tls_offload_sync_type resync_type; 320 /* this member is set regardless of resync_type, to avoid branches */ 321 u8 resync_nh_reset:1; 322 /* CORE_NEXT_HINT-only member, but use the hole here */ 323 u8 resync_nh_do_now:1; 324 union { 325 /* TLS_OFFLOAD_SYNC_TYPE_DRIVER_REQ */ 326 struct { 327 atomic64_t resync_req; 328 }; 329 /* TLS_OFFLOAD_SYNC_TYPE_CORE_NEXT_HINT */ 330 struct { 331 u32 decrypted_failed; 332 u32 decrypted_tgt; 333 } resync_nh; 334 /* TLS_OFFLOAD_SYNC_TYPE_DRIVER_REQ_ASYNC */ 335 struct { 336 struct tls_offload_resync_async *resync_async; 337 }; 338 }; 339 u8 driver_state[] __aligned(8); 340 /* The TLS layer reserves room for driver specific state 341 * Currently the belief is that there is not enough 342 * driver specific state to justify another layer of indirection 343 */ 344 #define TLS_DRIVER_STATE_SIZE_RX 8 345 }; 346 347 #define TLS_OFFLOAD_CONTEXT_SIZE_RX \ 348 (sizeof(struct tls_offload_context_rx) + TLS_DRIVER_STATE_SIZE_RX) 349 350 struct tls_record_info *tls_get_record(struct tls_offload_context_tx *context, 351 u32 seq, u64 *p_record_sn); 352 353 static inline bool tls_record_is_start_marker(struct tls_record_info *rec) 354 { 355 return rec->len == 0; 356 } 357 358 static inline u32 tls_record_start_seq(struct tls_record_info *rec) 359 { 360 return rec->end_seq - rec->len; 361 } 362 363 struct sk_buff * 364 tls_validate_xmit_skb(struct sock *sk, struct net_device *dev, 365 struct sk_buff *skb); 366 struct sk_buff * 367 tls_validate_xmit_skb_sw(struct sock *sk, struct net_device *dev, 368 struct sk_buff *skb); 369 370 static inline bool tls_is_sk_tx_device_offloaded(struct sock *sk) 371 { 372 #ifdef CONFIG_SOCK_VALIDATE_XMIT 373 return sk_fullsock(sk) && 374 (smp_load_acquire(&sk->sk_validate_xmit_skb) == 375 &tls_validate_xmit_skb); 376 #else 377 return false; 378 #endif 379 } 380 381 static inline struct tls_context *tls_get_ctx(const struct sock *sk) 382 { 383 struct inet_connection_sock *icsk = inet_csk(sk); 384 385 /* Use RCU on icsk_ulp_data only for sock diag code, 386 * TLS data path doesn't need rcu_dereference(). 387 */ 388 return (__force void *)icsk->icsk_ulp_data; 389 } 390 391 static inline struct tls_sw_context_rx *tls_sw_ctx_rx( 392 const struct tls_context *tls_ctx) 393 { 394 return (struct tls_sw_context_rx *)tls_ctx->priv_ctx_rx; 395 } 396 397 static inline struct tls_sw_context_tx *tls_sw_ctx_tx( 398 const struct tls_context *tls_ctx) 399 { 400 return (struct tls_sw_context_tx *)tls_ctx->priv_ctx_tx; 401 } 402 403 static inline struct tls_offload_context_tx * 404 tls_offload_ctx_tx(const struct tls_context *tls_ctx) 405 { 406 return (struct tls_offload_context_tx *)tls_ctx->priv_ctx_tx; 407 } 408 409 static inline bool tls_sw_has_ctx_tx(const struct sock *sk) 410 { 411 struct tls_context *ctx = tls_get_ctx(sk); 412 413 if (!ctx) 414 return false; 415 return !!tls_sw_ctx_tx(ctx); 416 } 417 418 static inline bool tls_sw_has_ctx_rx(const struct sock *sk) 419 { 420 struct tls_context *ctx = tls_get_ctx(sk); 421 422 if (!ctx) 423 return false; 424 return !!tls_sw_ctx_rx(ctx); 425 } 426 427 static inline struct tls_offload_context_rx * 428 tls_offload_ctx_rx(const struct tls_context *tls_ctx) 429 { 430 return (struct tls_offload_context_rx *)tls_ctx->priv_ctx_rx; 431 } 432 433 static inline void *__tls_driver_ctx(struct tls_context *tls_ctx, 434 enum tls_offload_ctx_dir direction) 435 { 436 if (direction == TLS_OFFLOAD_CTX_DIR_TX) 437 return tls_offload_ctx_tx(tls_ctx)->driver_state; 438 else 439 return tls_offload_ctx_rx(tls_ctx)->driver_state; 440 } 441 442 static inline void * 443 tls_driver_ctx(const struct sock *sk, enum tls_offload_ctx_dir direction) 444 { 445 return __tls_driver_ctx(tls_get_ctx(sk), direction); 446 } 447 448 #define RESYNC_REQ BIT(0) 449 #define RESYNC_REQ_ASYNC BIT(1) 450 /* The TLS context is valid until sk_destruct is called */ 451 static inline void tls_offload_rx_resync_request(struct sock *sk, __be32 seq) 452 { 453 struct tls_context *tls_ctx = tls_get_ctx(sk); 454 struct tls_offload_context_rx *rx_ctx = tls_offload_ctx_rx(tls_ctx); 455 456 atomic64_set(&rx_ctx->resync_req, ((u64)ntohl(seq) << 32) | RESYNC_REQ); 457 } 458 459 /* Log all TLS record header TCP sequences in [seq, seq+len] */ 460 static inline void 461 tls_offload_rx_resync_async_request_start(struct sock *sk, __be32 seq, u16 len) 462 { 463 struct tls_context *tls_ctx = tls_get_ctx(sk); 464 struct tls_offload_context_rx *rx_ctx = tls_offload_ctx_rx(tls_ctx); 465 466 atomic64_set(&rx_ctx->resync_async->req, ((u64)ntohl(seq) << 32) | 467 ((u64)len << 16) | RESYNC_REQ | RESYNC_REQ_ASYNC); 468 rx_ctx->resync_async->loglen = 0; 469 rx_ctx->resync_async->rcd_delta = 0; 470 } 471 472 static inline void 473 tls_offload_rx_resync_async_request_end(struct sock *sk, __be32 seq) 474 { 475 struct tls_context *tls_ctx = tls_get_ctx(sk); 476 struct tls_offload_context_rx *rx_ctx = tls_offload_ctx_rx(tls_ctx); 477 478 atomic64_set(&rx_ctx->resync_async->req, 479 ((u64)ntohl(seq) << 32) | RESYNC_REQ); 480 } 481 482 static inline void 483 tls_offload_rx_resync_set_type(struct sock *sk, enum tls_offload_sync_type type) 484 { 485 struct tls_context *tls_ctx = tls_get_ctx(sk); 486 487 tls_offload_ctx_rx(tls_ctx)->resync_type = type; 488 } 489 490 /* Driver's seq tracking has to be disabled until resync succeeded */ 491 static inline bool tls_offload_tx_resync_pending(struct sock *sk) 492 { 493 struct tls_context *tls_ctx = tls_get_ctx(sk); 494 bool ret; 495 496 ret = test_bit(TLS_TX_SYNC_SCHED, &tls_ctx->flags); 497 smp_mb__after_atomic(); 498 return ret; 499 } 500 501 struct sk_buff *tls_encrypt_skb(struct sk_buff *skb); 502 503 #ifdef CONFIG_TLS_DEVICE 504 void tls_device_sk_destruct(struct sock *sk); 505 void tls_offload_tx_resync_request(struct sock *sk, u32 got_seq, u32 exp_seq); 506 507 static inline bool tls_is_sk_rx_device_offloaded(struct sock *sk) 508 { 509 if (!sk_fullsock(sk) || 510 smp_load_acquire(&sk->sk_destruct) != tls_device_sk_destruct) 511 return false; 512 return tls_get_ctx(sk)->rx_conf == TLS_HW; 513 } 514 #endif 515 #endif /* _TLS_OFFLOAD_H */ 516