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