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 #define TLS_MAX_REC_SEQ_SIZE 8 66 67 /* For AES-CCM, the full 16-bytes of IV is made of '4' fields of given sizes. 68 * 69 * IV[16] = b0[1] || implicit nonce[4] || explicit nonce[8] || length[3] 70 * 71 * The field 'length' is encoded in field 'b0' as '(length width - 1)'. 72 * Hence b0 contains (3 - 1) = 2. 73 */ 74 #define TLS_AES_CCM_IV_B0_BYTE 2 75 76 /* 77 * This structure defines the routines for Inline TLS driver. 78 * The following routines are optional and filled with a 79 * null pointer if not defined. 80 * 81 * @name: Its the name of registered Inline tls device 82 * @dev_list: Inline tls device list 83 * int (*feature)(struct tls_device *device); 84 * Called to return Inline TLS driver capability 85 * 86 * int (*hash)(struct tls_device *device, struct sock *sk); 87 * This function sets Inline driver for listen and program 88 * device specific functioanlity as required 89 * 90 * void (*unhash)(struct tls_device *device, struct sock *sk); 91 * This function cleans listen state set by Inline TLS driver 92 * 93 * void (*release)(struct kref *kref); 94 * Release the registered device and allocated resources 95 * @kref: Number of reference to tls_device 96 */ 97 struct tls_device { 98 char name[TLS_DEVICE_NAME_MAX]; 99 struct list_head dev_list; 100 int (*feature)(struct tls_device *device); 101 int (*hash)(struct tls_device *device, struct sock *sk); 102 void (*unhash)(struct tls_device *device, struct sock *sk); 103 void (*release)(struct kref *kref); 104 struct kref kref; 105 }; 106 107 enum { 108 TLS_BASE, 109 TLS_SW, 110 #ifdef CONFIG_TLS_DEVICE 111 TLS_HW, 112 #endif 113 TLS_HW_RECORD, 114 TLS_NUM_CONFIG, 115 }; 116 117 /* TLS records are maintained in 'struct tls_rec'. It stores the memory pages 118 * allocated or mapped for each TLS record. After encryption, the records are 119 * stores in a linked list. 120 */ 121 struct tls_rec { 122 struct list_head list; 123 int tx_ready; 124 int tx_flags; 125 int inplace_crypto; 126 127 struct sk_msg msg_plaintext; 128 struct sk_msg msg_encrypted; 129 130 /* AAD | msg_plaintext.sg.data | sg_tag */ 131 struct scatterlist sg_aead_in[2]; 132 /* AAD | msg_encrypted.sg.data (data contains overhead for hdr & iv & tag) */ 133 struct scatterlist sg_aead_out[2]; 134 135 char content_type; 136 struct scatterlist sg_content_type; 137 138 char aad_space[TLS_AAD_SPACE_SIZE]; 139 u8 iv_data[MAX_IV_SIZE]; 140 struct aead_request aead_req; 141 u8 aead_req_ctx[]; 142 }; 143 144 struct tls_msg { 145 struct strp_msg rxm; 146 u8 control; 147 }; 148 149 struct tx_work { 150 struct delayed_work work; 151 struct sock *sk; 152 }; 153 154 struct tls_sw_context_tx { 155 struct crypto_aead *aead_send; 156 struct crypto_wait async_wait; 157 struct tx_work tx_work; 158 struct tls_rec *open_rec; 159 struct list_head tx_list; 160 atomic_t encrypt_pending; 161 int async_notify; 162 int async_capable; 163 164 #define BIT_TX_SCHEDULED 0 165 unsigned long tx_bitmask; 166 }; 167 168 struct tls_sw_context_rx { 169 struct crypto_aead *aead_recv; 170 struct crypto_wait async_wait; 171 struct strparser strp; 172 struct sk_buff_head rx_list; /* list of decrypted 'data' records */ 173 void (*saved_data_ready)(struct sock *sk); 174 175 struct sk_buff *recv_pkt; 176 u8 control; 177 int async_capable; 178 bool decrypted; 179 atomic_t decrypt_pending; 180 bool async_notify; 181 }; 182 183 struct tls_record_info { 184 struct list_head list; 185 u32 end_seq; 186 int len; 187 int num_frags; 188 skb_frag_t frags[MAX_SKB_FRAGS]; 189 }; 190 191 struct tls_offload_context_tx { 192 struct crypto_aead *aead_send; 193 spinlock_t lock; /* protects records list */ 194 struct list_head records_list; 195 struct tls_record_info *open_record; 196 struct tls_record_info *retransmit_hint; 197 u64 hint_record_sn; 198 u64 unacked_record_sn; 199 200 struct scatterlist sg_tx_data[MAX_SKB_FRAGS]; 201 void (*sk_destruct)(struct sock *sk); 202 u8 driver_state[] __aligned(8); 203 /* The TLS layer reserves room for driver specific state 204 * Currently the belief is that there is not enough 205 * driver specific state to justify another layer of indirection 206 */ 207 #define TLS_DRIVER_STATE_SIZE_TX 16 208 }; 209 210 #define TLS_OFFLOAD_CONTEXT_SIZE_TX \ 211 (sizeof(struct tls_offload_context_tx) + TLS_DRIVER_STATE_SIZE_TX) 212 213 enum tls_context_flags { 214 TLS_RX_SYNC_RUNNING = 0, 215 }; 216 217 struct cipher_context { 218 char *iv; 219 char *rec_seq; 220 }; 221 222 union tls_crypto_context { 223 struct tls_crypto_info info; 224 union { 225 struct tls12_crypto_info_aes_gcm_128 aes_gcm_128; 226 struct tls12_crypto_info_aes_gcm_256 aes_gcm_256; 227 }; 228 }; 229 230 struct tls_prot_info { 231 u16 version; 232 u16 cipher_type; 233 u16 prepend_size; 234 u16 tag_size; 235 u16 overhead_size; 236 u16 iv_size; 237 u16 salt_size; 238 u16 rec_seq_size; 239 u16 aad_size; 240 u16 tail_size; 241 }; 242 243 struct tls_context { 244 /* read-only cache line */ 245 struct tls_prot_info prot_info; 246 247 u8 tx_conf:3; 248 u8 rx_conf:3; 249 250 int (*push_pending_record)(struct sock *sk, int flags); 251 void (*sk_write_space)(struct sock *sk); 252 253 void *priv_ctx_tx; 254 void *priv_ctx_rx; 255 256 struct net_device *netdev; 257 258 /* rw cache line */ 259 struct cipher_context tx; 260 struct cipher_context rx; 261 262 struct scatterlist *partially_sent_record; 263 u16 partially_sent_offset; 264 265 bool in_tcp_sendpages; 266 bool pending_open_record_frags; 267 unsigned long flags; 268 269 /* cache cold stuff */ 270 void (*sk_destruct)(struct sock *sk); 271 void (*sk_proto_close)(struct sock *sk, long timeout); 272 273 int (*setsockopt)(struct sock *sk, int level, 274 int optname, char __user *optval, 275 unsigned int optlen); 276 int (*getsockopt)(struct sock *sk, int level, 277 int optname, char __user *optval, 278 int __user *optlen); 279 int (*hash)(struct sock *sk); 280 void (*unhash)(struct sock *sk); 281 282 union tls_crypto_context crypto_send; 283 union tls_crypto_context crypto_recv; 284 285 struct list_head list; 286 refcount_t refcount; 287 }; 288 289 enum tls_offload_ctx_dir { 290 TLS_OFFLOAD_CTX_DIR_RX, 291 TLS_OFFLOAD_CTX_DIR_TX, 292 }; 293 294 struct tlsdev_ops { 295 int (*tls_dev_add)(struct net_device *netdev, struct sock *sk, 296 enum tls_offload_ctx_dir direction, 297 struct tls_crypto_info *crypto_info, 298 u32 start_offload_tcp_sn); 299 void (*tls_dev_del)(struct net_device *netdev, 300 struct tls_context *ctx, 301 enum tls_offload_ctx_dir direction); 302 void (*tls_dev_resync_rx)(struct net_device *netdev, 303 struct sock *sk, u32 seq, u8 *rcd_sn); 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 atomic64_t resync_req; 310 u8 driver_state[] __aligned(8); 311 /* The TLS layer reserves room for driver specific state 312 * Currently the belief is that there is not enough 313 * driver specific state to justify another layer of indirection 314 */ 315 #define TLS_DRIVER_STATE_SIZE_RX 8 316 }; 317 318 #define TLS_OFFLOAD_CONTEXT_SIZE_RX \ 319 (sizeof(struct tls_offload_context_rx) + TLS_DRIVER_STATE_SIZE_RX) 320 321 int wait_on_pending_writer(struct sock *sk, long *timeo); 322 int tls_sk_query(struct sock *sk, int optname, char __user *optval, 323 int __user *optlen); 324 int tls_sk_attach(struct sock *sk, int optname, char __user *optval, 325 unsigned int optlen); 326 327 int tls_set_sw_offload(struct sock *sk, struct tls_context *ctx, int tx); 328 int tls_sw_sendmsg(struct sock *sk, struct msghdr *msg, size_t size); 329 int tls_sw_sendpage(struct sock *sk, struct page *page, 330 int offset, size_t size, int flags); 331 void tls_sw_close(struct sock *sk, long timeout); 332 void tls_sw_free_resources_tx(struct sock *sk); 333 void tls_sw_free_resources_rx(struct sock *sk); 334 void tls_sw_release_resources_rx(struct sock *sk); 335 int tls_sw_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, 336 int nonblock, int flags, int *addr_len); 337 bool tls_sw_stream_read(const struct sock *sk); 338 ssize_t tls_sw_splice_read(struct socket *sock, loff_t *ppos, 339 struct pipe_inode_info *pipe, 340 size_t len, unsigned int flags); 341 342 int tls_set_device_offload(struct sock *sk, struct tls_context *ctx); 343 int tls_device_sendmsg(struct sock *sk, struct msghdr *msg, size_t size); 344 int tls_device_sendpage(struct sock *sk, struct page *page, 345 int offset, size_t size, int flags); 346 void tls_device_free_resources_tx(struct sock *sk); 347 void tls_device_init(void); 348 void tls_device_cleanup(void); 349 int tls_tx_records(struct sock *sk, int flags); 350 351 struct tls_record_info *tls_get_record(struct tls_offload_context_tx *context, 352 u32 seq, u64 *p_record_sn); 353 354 static inline bool tls_record_is_start_marker(struct tls_record_info *rec) 355 { 356 return rec->len == 0; 357 } 358 359 static inline u32 tls_record_start_seq(struct tls_record_info *rec) 360 { 361 return rec->end_seq - rec->len; 362 } 363 364 int tls_push_sg(struct sock *sk, struct tls_context *ctx, 365 struct scatterlist *sg, u16 first_offset, 366 int flags); 367 int tls_push_partial_record(struct sock *sk, struct tls_context *ctx, 368 int flags); 369 bool tls_free_partial_record(struct sock *sk, struct tls_context *ctx); 370 371 static inline struct tls_msg *tls_msg(struct sk_buff *skb) 372 { 373 return (struct tls_msg *)strp_msg(skb); 374 } 375 376 static inline bool tls_is_partially_sent_record(struct tls_context *ctx) 377 { 378 return !!ctx->partially_sent_record; 379 } 380 381 static inline int tls_complete_pending_work(struct sock *sk, 382 struct tls_context *ctx, 383 int flags, long *timeo) 384 { 385 int rc = 0; 386 387 if (unlikely(sk->sk_write_pending)) 388 rc = wait_on_pending_writer(sk, timeo); 389 390 if (!rc && tls_is_partially_sent_record(ctx)) 391 rc = tls_push_partial_record(sk, ctx, flags); 392 393 return rc; 394 } 395 396 static inline bool tls_is_pending_open_record(struct tls_context *tls_ctx) 397 { 398 return tls_ctx->pending_open_record_frags; 399 } 400 401 static inline bool is_tx_ready(struct tls_sw_context_tx *ctx) 402 { 403 struct tls_rec *rec; 404 405 rec = list_first_entry(&ctx->tx_list, struct tls_rec, list); 406 if (!rec) 407 return false; 408 409 return READ_ONCE(rec->tx_ready); 410 } 411 412 struct sk_buff * 413 tls_validate_xmit_skb(struct sock *sk, struct net_device *dev, 414 struct sk_buff *skb); 415 416 static inline bool tls_is_sk_tx_device_offloaded(struct sock *sk) 417 { 418 #ifdef CONFIG_SOCK_VALIDATE_XMIT 419 return sk_fullsock(sk) && 420 (smp_load_acquire(&sk->sk_validate_xmit_skb) == 421 &tls_validate_xmit_skb); 422 #else 423 return false; 424 #endif 425 } 426 427 static inline void tls_err_abort(struct sock *sk, int err) 428 { 429 sk->sk_err = err; 430 sk->sk_error_report(sk); 431 } 432 433 static inline bool tls_bigint_increment(unsigned char *seq, int len) 434 { 435 int i; 436 437 for (i = len - 1; i >= 0; i--) { 438 ++seq[i]; 439 if (seq[i] != 0) 440 break; 441 } 442 443 return (i == -1); 444 } 445 446 static inline struct tls_context *tls_get_ctx(const struct sock *sk) 447 { 448 struct inet_connection_sock *icsk = inet_csk(sk); 449 450 return icsk->icsk_ulp_data; 451 } 452 453 static inline void tls_advance_record_sn(struct sock *sk, 454 struct tls_prot_info *prot, 455 struct cipher_context *ctx) 456 { 457 if (tls_bigint_increment(ctx->rec_seq, prot->rec_seq_size)) 458 tls_err_abort(sk, EBADMSG); 459 460 if (prot->version != TLS_1_3_VERSION) 461 tls_bigint_increment(ctx->iv + TLS_CIPHER_AES_GCM_128_SALT_SIZE, 462 prot->iv_size); 463 } 464 465 static inline void tls_fill_prepend(struct tls_context *ctx, 466 char *buf, 467 size_t plaintext_len, 468 unsigned char record_type, 469 int version) 470 { 471 struct tls_prot_info *prot = &ctx->prot_info; 472 size_t pkt_len, iv_size = prot->iv_size; 473 474 pkt_len = plaintext_len + prot->tag_size; 475 if (version != TLS_1_3_VERSION) { 476 pkt_len += iv_size; 477 478 memcpy(buf + TLS_NONCE_OFFSET, 479 ctx->tx.iv + TLS_CIPHER_AES_GCM_128_SALT_SIZE, iv_size); 480 } 481 482 /* we cover nonce explicit here as well, so buf should be of 483 * size KTLS_DTLS_HEADER_SIZE + KTLS_DTLS_NONCE_EXPLICIT_SIZE 484 */ 485 buf[0] = version == TLS_1_3_VERSION ? 486 TLS_RECORD_TYPE_DATA : record_type; 487 /* Note that VERSION must be TLS_1_2 for both TLS1.2 and TLS1.3 */ 488 buf[1] = TLS_1_2_VERSION_MINOR; 489 buf[2] = TLS_1_2_VERSION_MAJOR; 490 /* we can use IV for nonce explicit according to spec */ 491 buf[3] = pkt_len >> 8; 492 buf[4] = pkt_len & 0xFF; 493 } 494 495 static inline void tls_make_aad(char *buf, 496 size_t size, 497 char *record_sequence, 498 int record_sequence_size, 499 unsigned char record_type, 500 int version) 501 { 502 if (version != TLS_1_3_VERSION) { 503 memcpy(buf, record_sequence, record_sequence_size); 504 buf += 8; 505 } else { 506 size += TLS_CIPHER_AES_GCM_128_TAG_SIZE; 507 } 508 509 buf[0] = version == TLS_1_3_VERSION ? 510 TLS_RECORD_TYPE_DATA : record_type; 511 buf[1] = TLS_1_2_VERSION_MAJOR; 512 buf[2] = TLS_1_2_VERSION_MINOR; 513 buf[3] = size >> 8; 514 buf[4] = size & 0xFF; 515 } 516 517 static inline void xor_iv_with_seq(int version, char *iv, char *seq) 518 { 519 int i; 520 521 if (version == TLS_1_3_VERSION) { 522 for (i = 0; i < 8; i++) 523 iv[i + 4] ^= seq[i]; 524 } 525 } 526 527 528 static inline struct tls_sw_context_rx *tls_sw_ctx_rx( 529 const struct tls_context *tls_ctx) 530 { 531 return (struct tls_sw_context_rx *)tls_ctx->priv_ctx_rx; 532 } 533 534 static inline struct tls_sw_context_tx *tls_sw_ctx_tx( 535 const struct tls_context *tls_ctx) 536 { 537 return (struct tls_sw_context_tx *)tls_ctx->priv_ctx_tx; 538 } 539 540 static inline struct tls_offload_context_tx * 541 tls_offload_ctx_tx(const struct tls_context *tls_ctx) 542 { 543 return (struct tls_offload_context_tx *)tls_ctx->priv_ctx_tx; 544 } 545 546 static inline bool tls_sw_has_ctx_tx(const struct sock *sk) 547 { 548 struct tls_context *ctx = tls_get_ctx(sk); 549 550 if (!ctx) 551 return false; 552 return !!tls_sw_ctx_tx(ctx); 553 } 554 555 void tls_sw_write_space(struct sock *sk, struct tls_context *ctx); 556 void tls_device_write_space(struct sock *sk, struct tls_context *ctx); 557 558 static inline struct tls_offload_context_rx * 559 tls_offload_ctx_rx(const struct tls_context *tls_ctx) 560 { 561 return (struct tls_offload_context_rx *)tls_ctx->priv_ctx_rx; 562 } 563 564 #if IS_ENABLED(CONFIG_TLS_DEVICE) 565 static inline void *__tls_driver_ctx(struct tls_context *tls_ctx, 566 enum tls_offload_ctx_dir direction) 567 { 568 if (direction == TLS_OFFLOAD_CTX_DIR_TX) 569 return tls_offload_ctx_tx(tls_ctx)->driver_state; 570 else 571 return tls_offload_ctx_rx(tls_ctx)->driver_state; 572 } 573 574 static inline void * 575 tls_driver_ctx(const struct sock *sk, enum tls_offload_ctx_dir direction) 576 { 577 return __tls_driver_ctx(tls_get_ctx(sk), direction); 578 } 579 #endif 580 581 /* The TLS context is valid until sk_destruct is called */ 582 static inline void tls_offload_rx_resync_request(struct sock *sk, __be32 seq) 583 { 584 struct tls_context *tls_ctx = tls_get_ctx(sk); 585 struct tls_offload_context_rx *rx_ctx = tls_offload_ctx_rx(tls_ctx); 586 587 atomic64_set(&rx_ctx->resync_req, ((u64)ntohl(seq) << 32) | 1); 588 } 589 590 591 int tls_proccess_cmsg(struct sock *sk, struct msghdr *msg, 592 unsigned char *record_type); 593 void tls_register_device(struct tls_device *device); 594 void tls_unregister_device(struct tls_device *device); 595 int tls_device_decrypted(struct sock *sk, struct sk_buff *skb); 596 int decrypt_skb(struct sock *sk, struct sk_buff *skb, 597 struct scatterlist *sgout); 598 struct sk_buff *tls_encrypt_skb(struct sk_buff *skb); 599 600 struct sk_buff *tls_validate_xmit_skb(struct sock *sk, 601 struct net_device *dev, 602 struct sk_buff *skb); 603 604 int tls_sw_fallback_init(struct sock *sk, 605 struct tls_offload_context_tx *offload_ctx, 606 struct tls_crypto_info *crypto_info); 607 608 int tls_set_device_offload_rx(struct sock *sk, struct tls_context *ctx); 609 610 void tls_device_offload_cleanup_rx(struct sock *sk); 611 void tls_device_rx_resync_new_rec(struct sock *sk, u32 seq); 612 613 #endif /* _TLS_OFFLOAD_H */ 614