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/skmsg.h> 43 #include <linux/netdevice.h> 44 45 #include <net/tcp.h> 46 #include <net/strparser.h> 47 #include <crypto/aead.h> 48 #include <uapi/linux/tls.h> 49 50 51 /* Maximum data size carried in a TLS record */ 52 #define TLS_MAX_PAYLOAD_SIZE ((size_t)1 << 14) 53 54 #define TLS_HEADER_SIZE 5 55 #define TLS_NONCE_OFFSET TLS_HEADER_SIZE 56 57 #define TLS_CRYPTO_INFO_READY(info) ((info)->cipher_type) 58 59 #define TLS_RECORD_TYPE_DATA 0x17 60 61 #define TLS_AAD_SPACE_SIZE 13 62 #define TLS_DEVICE_NAME_MAX 32 63 64 #define MAX_IV_SIZE 16 65 66 /* For AES-CCM, the full 16-bytes of IV is made of '4' fields of given sizes. 67 * 68 * IV[16] = b0[1] || implicit nonce[4] || explicit nonce[8] || length[3] 69 * 70 * The field 'length' is encoded in field 'b0' as '(length width - 1)'. 71 * Hence b0 contains (3 - 1) = 2. 72 */ 73 #define TLS_AES_CCM_IV_B0_BYTE 2 74 75 /* 76 * This structure defines the routines for Inline TLS driver. 77 * The following routines are optional and filled with a 78 * null pointer if not defined. 79 * 80 * @name: Its the name of registered Inline tls device 81 * @dev_list: Inline tls device list 82 * int (*feature)(struct tls_device *device); 83 * Called to return Inline TLS driver capability 84 * 85 * int (*hash)(struct tls_device *device, struct sock *sk); 86 * This function sets Inline driver for listen and program 87 * device specific functioanlity as required 88 * 89 * void (*unhash)(struct tls_device *device, struct sock *sk); 90 * This function cleans listen state set by Inline TLS driver 91 * 92 * void (*release)(struct kref *kref); 93 * Release the registered device and allocated resources 94 * @kref: Number of reference to tls_device 95 */ 96 struct tls_device { 97 char name[TLS_DEVICE_NAME_MAX]; 98 struct list_head dev_list; 99 int (*feature)(struct tls_device *device); 100 int (*hash)(struct tls_device *device, struct sock *sk); 101 void (*unhash)(struct tls_device *device, struct sock *sk); 102 void (*release)(struct kref *kref); 103 struct kref kref; 104 }; 105 106 enum { 107 TLS_BASE, 108 TLS_SW, 109 #ifdef CONFIG_TLS_DEVICE 110 TLS_HW, 111 #endif 112 TLS_HW_RECORD, 113 TLS_NUM_CONFIG, 114 }; 115 116 /* TLS records are maintained in 'struct tls_rec'. It stores the memory pages 117 * allocated or mapped for each TLS record. After encryption, the records are 118 * stores in a linked list. 119 */ 120 struct tls_rec { 121 struct list_head list; 122 int tx_ready; 123 int tx_flags; 124 int inplace_crypto; 125 126 struct sk_msg msg_plaintext; 127 struct sk_msg msg_encrypted; 128 129 /* AAD | msg_plaintext.sg.data | sg_tag */ 130 struct scatterlist sg_aead_in[2]; 131 /* AAD | msg_encrypted.sg.data (data contains overhead for hdr & iv & tag) */ 132 struct scatterlist sg_aead_out[2]; 133 134 char content_type; 135 struct scatterlist sg_content_type; 136 137 char aad_space[TLS_AAD_SPACE_SIZE]; 138 u8 iv_data[MAX_IV_SIZE]; 139 struct aead_request aead_req; 140 u8 aead_req_ctx[]; 141 }; 142 143 struct tls_msg { 144 struct strp_msg rxm; 145 u8 control; 146 }; 147 148 struct tx_work { 149 struct delayed_work work; 150 struct sock *sk; 151 }; 152 153 struct tls_sw_context_tx { 154 struct crypto_aead *aead_send; 155 struct crypto_wait async_wait; 156 struct tx_work tx_work; 157 struct tls_rec *open_rec; 158 struct list_head tx_list; 159 atomic_t encrypt_pending; 160 int async_notify; 161 int async_capable; 162 163 #define BIT_TX_SCHEDULED 0 164 unsigned long tx_bitmask; 165 }; 166 167 struct tls_sw_context_rx { 168 struct crypto_aead *aead_recv; 169 struct crypto_wait async_wait; 170 struct strparser strp; 171 struct sk_buff_head rx_list; /* list of decrypted 'data' records */ 172 void (*saved_data_ready)(struct sock *sk); 173 174 struct sk_buff *recv_pkt; 175 u8 control; 176 int async_capable; 177 bool decrypted; 178 atomic_t decrypt_pending; 179 bool async_notify; 180 }; 181 182 struct tls_record_info { 183 struct list_head list; 184 u32 end_seq; 185 int len; 186 int num_frags; 187 skb_frag_t frags[MAX_SKB_FRAGS]; 188 }; 189 190 struct tls_offload_context_tx { 191 struct crypto_aead *aead_send; 192 spinlock_t lock; /* protects records list */ 193 struct list_head records_list; 194 struct tls_record_info *open_record; 195 struct tls_record_info *retransmit_hint; 196 u64 hint_record_sn; 197 u64 unacked_record_sn; 198 199 struct scatterlist sg_tx_data[MAX_SKB_FRAGS]; 200 void (*sk_destruct)(struct sock *sk); 201 u8 driver_state[] __aligned(8); 202 /* The TLS layer reserves room for driver specific state 203 * Currently the belief is that there is not enough 204 * driver specific state to justify another layer of indirection 205 */ 206 #define TLS_DRIVER_STATE_SIZE_TX 16 207 }; 208 209 #define TLS_OFFLOAD_CONTEXT_SIZE_TX \ 210 (sizeof(struct tls_offload_context_tx) + TLS_DRIVER_STATE_SIZE_TX) 211 212 enum tls_context_flags { 213 TLS_RX_SYNC_RUNNING = 0, 214 }; 215 216 struct cipher_context { 217 char *iv; 218 char *rec_seq; 219 }; 220 221 union tls_crypto_context { 222 struct tls_crypto_info info; 223 union { 224 struct tls12_crypto_info_aes_gcm_128 aes_gcm_128; 225 struct tls12_crypto_info_aes_gcm_256 aes_gcm_256; 226 }; 227 }; 228 229 struct tls_prot_info { 230 u16 version; 231 u16 cipher_type; 232 u16 prepend_size; 233 u16 tag_size; 234 u16 overhead_size; 235 u16 iv_size; 236 u16 salt_size; 237 u16 rec_seq_size; 238 u16 aad_size; 239 u16 tail_size; 240 }; 241 242 struct tls_context { 243 /* read-only cache line */ 244 struct tls_prot_info prot_info; 245 246 u8 tx_conf:3; 247 u8 rx_conf:3; 248 249 int (*push_pending_record)(struct sock *sk, int flags); 250 void (*sk_write_space)(struct sock *sk); 251 252 void *priv_ctx_tx; 253 void *priv_ctx_rx; 254 255 struct net_device *netdev; 256 257 /* rw cache line */ 258 struct cipher_context tx; 259 struct cipher_context rx; 260 261 struct scatterlist *partially_sent_record; 262 u16 partially_sent_offset; 263 264 bool in_tcp_sendpages; 265 bool pending_open_record_frags; 266 unsigned long flags; 267 268 /* cache cold stuff */ 269 void (*sk_destruct)(struct sock *sk); 270 void (*sk_proto_close)(struct sock *sk, long timeout); 271 272 int (*setsockopt)(struct sock *sk, int level, 273 int optname, char __user *optval, 274 unsigned int optlen); 275 int (*getsockopt)(struct sock *sk, int level, 276 int optname, char __user *optval, 277 int __user *optlen); 278 int (*hash)(struct sock *sk); 279 void (*unhash)(struct sock *sk); 280 281 union tls_crypto_context crypto_send; 282 union tls_crypto_context crypto_recv; 283 284 struct list_head list; 285 refcount_t refcount; 286 }; 287 288 enum tls_offload_ctx_dir { 289 TLS_OFFLOAD_CTX_DIR_RX, 290 TLS_OFFLOAD_CTX_DIR_TX, 291 }; 292 293 struct tlsdev_ops { 294 int (*tls_dev_add)(struct net_device *netdev, struct sock *sk, 295 enum tls_offload_ctx_dir direction, 296 struct tls_crypto_info *crypto_info, 297 u32 start_offload_tcp_sn); 298 void (*tls_dev_del)(struct net_device *netdev, 299 struct tls_context *ctx, 300 enum tls_offload_ctx_dir direction); 301 void (*tls_dev_resync_rx)(struct net_device *netdev, 302 struct sock *sk, u32 seq, u64 rcd_sn); 303 }; 304 305 struct tls_offload_context_rx { 306 /* sw must be the first member of tls_offload_context_rx */ 307 struct tls_sw_context_rx sw; 308 atomic64_t resync_req; 309 u8 driver_state[] __aligned(8); 310 /* The TLS layer reserves room for driver specific state 311 * Currently the belief is that there is not enough 312 * driver specific state to justify another layer of indirection 313 */ 314 #define TLS_DRIVER_STATE_SIZE_RX 8 315 }; 316 317 #define TLS_OFFLOAD_CONTEXT_SIZE_RX \ 318 (sizeof(struct tls_offload_context_rx) + TLS_DRIVER_STATE_SIZE_RX) 319 320 int wait_on_pending_writer(struct sock *sk, long *timeo); 321 int tls_sk_query(struct sock *sk, int optname, char __user *optval, 322 int __user *optlen); 323 int tls_sk_attach(struct sock *sk, int optname, char __user *optval, 324 unsigned int optlen); 325 326 int tls_set_sw_offload(struct sock *sk, struct tls_context *ctx, int tx); 327 int tls_sw_sendmsg(struct sock *sk, struct msghdr *msg, size_t size); 328 int tls_sw_sendpage(struct sock *sk, struct page *page, 329 int offset, size_t size, int flags); 330 void tls_sw_close(struct sock *sk, long timeout); 331 void tls_sw_free_resources_tx(struct sock *sk); 332 void tls_sw_free_resources_rx(struct sock *sk); 333 void tls_sw_release_resources_rx(struct sock *sk); 334 int tls_sw_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, 335 int nonblock, int flags, int *addr_len); 336 bool tls_sw_stream_read(const struct sock *sk); 337 ssize_t tls_sw_splice_read(struct socket *sock, loff_t *ppos, 338 struct pipe_inode_info *pipe, 339 size_t len, unsigned int flags); 340 341 int tls_set_device_offload(struct sock *sk, struct tls_context *ctx); 342 int tls_device_sendmsg(struct sock *sk, struct msghdr *msg, size_t size); 343 int tls_device_sendpage(struct sock *sk, struct page *page, 344 int offset, size_t size, int flags); 345 void tls_device_free_resources_tx(struct sock *sk); 346 void tls_device_init(void); 347 void tls_device_cleanup(void); 348 int tls_tx_records(struct sock *sk, int flags); 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 int tls_push_sg(struct sock *sk, struct tls_context *ctx, 364 struct scatterlist *sg, u16 first_offset, 365 int flags); 366 int tls_push_partial_record(struct sock *sk, struct tls_context *ctx, 367 int flags); 368 bool tls_free_partial_record(struct sock *sk, struct tls_context *ctx); 369 370 static inline struct tls_msg *tls_msg(struct sk_buff *skb) 371 { 372 return (struct tls_msg *)strp_msg(skb); 373 } 374 375 static inline bool tls_is_partially_sent_record(struct tls_context *ctx) 376 { 377 return !!ctx->partially_sent_record; 378 } 379 380 static inline int tls_complete_pending_work(struct sock *sk, 381 struct tls_context *ctx, 382 int flags, long *timeo) 383 { 384 int rc = 0; 385 386 if (unlikely(sk->sk_write_pending)) 387 rc = wait_on_pending_writer(sk, timeo); 388 389 if (!rc && tls_is_partially_sent_record(ctx)) 390 rc = tls_push_partial_record(sk, ctx, flags); 391 392 return rc; 393 } 394 395 static inline bool tls_is_pending_open_record(struct tls_context *tls_ctx) 396 { 397 return tls_ctx->pending_open_record_frags; 398 } 399 400 static inline bool is_tx_ready(struct tls_sw_context_tx *ctx) 401 { 402 struct tls_rec *rec; 403 404 rec = list_first_entry(&ctx->tx_list, struct tls_rec, list); 405 if (!rec) 406 return false; 407 408 return READ_ONCE(rec->tx_ready); 409 } 410 411 struct sk_buff * 412 tls_validate_xmit_skb(struct sock *sk, struct net_device *dev, 413 struct sk_buff *skb); 414 415 static inline bool tls_is_sk_tx_device_offloaded(struct sock *sk) 416 { 417 #ifdef CONFIG_SOCK_VALIDATE_XMIT 418 return sk_fullsock(sk) && 419 (smp_load_acquire(&sk->sk_validate_xmit_skb) == 420 &tls_validate_xmit_skb); 421 #else 422 return false; 423 #endif 424 } 425 426 static inline void tls_err_abort(struct sock *sk, int err) 427 { 428 sk->sk_err = err; 429 sk->sk_error_report(sk); 430 } 431 432 static inline bool tls_bigint_increment(unsigned char *seq, int len) 433 { 434 int i; 435 436 for (i = len - 1; i >= 0; i--) { 437 ++seq[i]; 438 if (seq[i] != 0) 439 break; 440 } 441 442 return (i == -1); 443 } 444 445 static inline struct tls_context *tls_get_ctx(const struct sock *sk) 446 { 447 struct inet_connection_sock *icsk = inet_csk(sk); 448 449 return icsk->icsk_ulp_data; 450 } 451 452 static inline void tls_advance_record_sn(struct sock *sk, 453 struct tls_prot_info *prot, 454 struct cipher_context *ctx) 455 { 456 if (tls_bigint_increment(ctx->rec_seq, prot->rec_seq_size)) 457 tls_err_abort(sk, EBADMSG); 458 459 if (prot->version != TLS_1_3_VERSION) 460 tls_bigint_increment(ctx->iv + TLS_CIPHER_AES_GCM_128_SALT_SIZE, 461 prot->iv_size); 462 } 463 464 static inline void tls_fill_prepend(struct tls_context *ctx, 465 char *buf, 466 size_t plaintext_len, 467 unsigned char record_type, 468 int version) 469 { 470 struct tls_prot_info *prot = &ctx->prot_info; 471 size_t pkt_len, iv_size = prot->iv_size; 472 473 pkt_len = plaintext_len + prot->tag_size; 474 if (version != TLS_1_3_VERSION) { 475 pkt_len += iv_size; 476 477 memcpy(buf + TLS_NONCE_OFFSET, 478 ctx->tx.iv + TLS_CIPHER_AES_GCM_128_SALT_SIZE, iv_size); 479 } 480 481 /* we cover nonce explicit here as well, so buf should be of 482 * size KTLS_DTLS_HEADER_SIZE + KTLS_DTLS_NONCE_EXPLICIT_SIZE 483 */ 484 buf[0] = version == TLS_1_3_VERSION ? 485 TLS_RECORD_TYPE_DATA : record_type; 486 /* Note that VERSION must be TLS_1_2 for both TLS1.2 and TLS1.3 */ 487 buf[1] = TLS_1_2_VERSION_MINOR; 488 buf[2] = TLS_1_2_VERSION_MAJOR; 489 /* we can use IV for nonce explicit according to spec */ 490 buf[3] = pkt_len >> 8; 491 buf[4] = pkt_len & 0xFF; 492 } 493 494 static inline void tls_make_aad(char *buf, 495 size_t size, 496 char *record_sequence, 497 int record_sequence_size, 498 unsigned char record_type, 499 int version) 500 { 501 if (version != TLS_1_3_VERSION) { 502 memcpy(buf, record_sequence, record_sequence_size); 503 buf += 8; 504 } else { 505 size += TLS_CIPHER_AES_GCM_128_TAG_SIZE; 506 } 507 508 buf[0] = version == TLS_1_3_VERSION ? 509 TLS_RECORD_TYPE_DATA : record_type; 510 buf[1] = TLS_1_2_VERSION_MAJOR; 511 buf[2] = TLS_1_2_VERSION_MINOR; 512 buf[3] = size >> 8; 513 buf[4] = size & 0xFF; 514 } 515 516 static inline void xor_iv_with_seq(int version, char *iv, char *seq) 517 { 518 int i; 519 520 if (version == TLS_1_3_VERSION) { 521 for (i = 0; i < 8; i++) 522 iv[i + 4] ^= seq[i]; 523 } 524 } 525 526 527 static inline struct tls_sw_context_rx *tls_sw_ctx_rx( 528 const struct tls_context *tls_ctx) 529 { 530 return (struct tls_sw_context_rx *)tls_ctx->priv_ctx_rx; 531 } 532 533 static inline struct tls_sw_context_tx *tls_sw_ctx_tx( 534 const struct tls_context *tls_ctx) 535 { 536 return (struct tls_sw_context_tx *)tls_ctx->priv_ctx_tx; 537 } 538 539 static inline struct tls_offload_context_tx * 540 tls_offload_ctx_tx(const struct tls_context *tls_ctx) 541 { 542 return (struct tls_offload_context_tx *)tls_ctx->priv_ctx_tx; 543 } 544 545 static inline bool tls_sw_has_ctx_tx(const struct sock *sk) 546 { 547 struct tls_context *ctx = tls_get_ctx(sk); 548 549 if (!ctx) 550 return false; 551 return !!tls_sw_ctx_tx(ctx); 552 } 553 554 void tls_sw_write_space(struct sock *sk, struct tls_context *ctx); 555 void tls_device_write_space(struct sock *sk, struct tls_context *ctx); 556 557 static inline struct tls_offload_context_rx * 558 tls_offload_ctx_rx(const struct tls_context *tls_ctx) 559 { 560 return (struct tls_offload_context_rx *)tls_ctx->priv_ctx_rx; 561 } 562 563 #if IS_ENABLED(CONFIG_TLS_DEVICE) 564 static inline void *__tls_driver_ctx(struct tls_context *tls_ctx, 565 enum tls_offload_ctx_dir direction) 566 { 567 if (direction == TLS_OFFLOAD_CTX_DIR_TX) 568 return tls_offload_ctx_tx(tls_ctx)->driver_state; 569 else 570 return tls_offload_ctx_rx(tls_ctx)->driver_state; 571 } 572 573 static inline void * 574 tls_driver_ctx(const struct sock *sk, enum tls_offload_ctx_dir direction) 575 { 576 return __tls_driver_ctx(tls_get_ctx(sk), direction); 577 } 578 #endif 579 580 /* The TLS context is valid until sk_destruct is called */ 581 static inline void tls_offload_rx_resync_request(struct sock *sk, __be32 seq) 582 { 583 struct tls_context *tls_ctx = tls_get_ctx(sk); 584 struct tls_offload_context_rx *rx_ctx = tls_offload_ctx_rx(tls_ctx); 585 586 atomic64_set(&rx_ctx->resync_req, ((u64)ntohl(seq) << 32) | 1); 587 } 588 589 590 int tls_proccess_cmsg(struct sock *sk, struct msghdr *msg, 591 unsigned char *record_type); 592 void tls_register_device(struct tls_device *device); 593 void tls_unregister_device(struct tls_device *device); 594 int tls_device_decrypted(struct sock *sk, struct sk_buff *skb); 595 int decrypt_skb(struct sock *sk, struct sk_buff *skb, 596 struct scatterlist *sgout); 597 struct sk_buff *tls_encrypt_skb(struct sk_buff *skb); 598 599 struct sk_buff *tls_validate_xmit_skb(struct sock *sk, 600 struct net_device *dev, 601 struct sk_buff *skb); 602 603 int tls_sw_fallback_init(struct sock *sk, 604 struct tls_offload_context_tx *offload_ctx, 605 struct tls_crypto_info *crypto_info); 606 607 int tls_set_device_offload_rx(struct sock *sk, struct tls_context *ctx); 608 609 void tls_device_offload_cleanup_rx(struct sock *sk); 610 void handle_device_resync(struct sock *sk, u32 seq, u64 rcd_sn); 611 612 #endif /* _TLS_OFFLOAD_H */ 613