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 struct cipher_context { 213 char *iv; 214 char *rec_seq; 215 }; 216 217 union tls_crypto_context { 218 struct tls_crypto_info info; 219 union { 220 struct tls12_crypto_info_aes_gcm_128 aes_gcm_128; 221 struct tls12_crypto_info_aes_gcm_256 aes_gcm_256; 222 }; 223 }; 224 225 struct tls_prot_info { 226 u16 version; 227 u16 cipher_type; 228 u16 prepend_size; 229 u16 tag_size; 230 u16 overhead_size; 231 u16 iv_size; 232 u16 salt_size; 233 u16 rec_seq_size; 234 u16 aad_size; 235 u16 tail_size; 236 }; 237 238 struct tls_context { 239 /* read-only cache line */ 240 struct tls_prot_info prot_info; 241 242 u8 tx_conf:3; 243 u8 rx_conf:3; 244 245 int (*push_pending_record)(struct sock *sk, int flags); 246 void (*sk_write_space)(struct sock *sk); 247 248 void *priv_ctx_tx; 249 void *priv_ctx_rx; 250 251 struct net_device *netdev; 252 253 /* rw cache line */ 254 struct cipher_context tx; 255 struct cipher_context rx; 256 257 struct scatterlist *partially_sent_record; 258 u16 partially_sent_offset; 259 260 bool in_tcp_sendpages; 261 bool pending_open_record_frags; 262 unsigned long flags; 263 264 /* cache cold stuff */ 265 void (*sk_destruct)(struct sock *sk); 266 void (*sk_proto_close)(struct sock *sk, long timeout); 267 268 int (*setsockopt)(struct sock *sk, int level, 269 int optname, char __user *optval, 270 unsigned int optlen); 271 int (*getsockopt)(struct sock *sk, int level, 272 int optname, char __user *optval, 273 int __user *optlen); 274 int (*hash)(struct sock *sk); 275 void (*unhash)(struct sock *sk); 276 277 union tls_crypto_context crypto_send; 278 union tls_crypto_context crypto_recv; 279 280 struct list_head list; 281 refcount_t refcount; 282 }; 283 284 enum tls_offload_ctx_dir { 285 TLS_OFFLOAD_CTX_DIR_RX, 286 TLS_OFFLOAD_CTX_DIR_TX, 287 }; 288 289 struct tlsdev_ops { 290 int (*tls_dev_add)(struct net_device *netdev, struct sock *sk, 291 enum tls_offload_ctx_dir direction, 292 struct tls_crypto_info *crypto_info, 293 u32 start_offload_tcp_sn); 294 void (*tls_dev_del)(struct net_device *netdev, 295 struct tls_context *ctx, 296 enum tls_offload_ctx_dir direction); 297 void (*tls_dev_resync_rx)(struct net_device *netdev, 298 struct sock *sk, u32 seq, u64 rcd_sn); 299 }; 300 301 struct tls_offload_context_rx { 302 /* sw must be the first member of tls_offload_context_rx */ 303 struct tls_sw_context_rx sw; 304 atomic64_t resync_req; 305 u8 driver_state[] __aligned(8); 306 /* The TLS layer reserves room for driver specific state 307 * Currently the belief is that there is not enough 308 * driver specific state to justify another layer of indirection 309 */ 310 #define TLS_DRIVER_STATE_SIZE_RX 8 311 }; 312 313 #define TLS_OFFLOAD_CONTEXT_SIZE_RX \ 314 (sizeof(struct tls_offload_context_rx) + TLS_DRIVER_STATE_SIZE_RX) 315 316 int wait_on_pending_writer(struct sock *sk, long *timeo); 317 int tls_sk_query(struct sock *sk, int optname, char __user *optval, 318 int __user *optlen); 319 int tls_sk_attach(struct sock *sk, int optname, char __user *optval, 320 unsigned int optlen); 321 322 int tls_set_sw_offload(struct sock *sk, struct tls_context *ctx, int tx); 323 int tls_sw_sendmsg(struct sock *sk, struct msghdr *msg, size_t size); 324 int tls_sw_sendpage(struct sock *sk, struct page *page, 325 int offset, size_t size, int flags); 326 void tls_sw_close(struct sock *sk, long timeout); 327 void tls_sw_free_resources_tx(struct sock *sk); 328 void tls_sw_free_resources_rx(struct sock *sk); 329 void tls_sw_release_resources_rx(struct sock *sk); 330 int tls_sw_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, 331 int nonblock, int flags, int *addr_len); 332 bool tls_sw_stream_read(const struct sock *sk); 333 ssize_t tls_sw_splice_read(struct socket *sock, loff_t *ppos, 334 struct pipe_inode_info *pipe, 335 size_t len, unsigned int flags); 336 337 int tls_set_device_offload(struct sock *sk, struct tls_context *ctx); 338 int tls_device_sendmsg(struct sock *sk, struct msghdr *msg, size_t size); 339 int tls_device_sendpage(struct sock *sk, struct page *page, 340 int offset, size_t size, int flags); 341 void tls_device_free_resources_tx(struct sock *sk); 342 void tls_device_init(void); 343 void tls_device_cleanup(void); 344 int tls_tx_records(struct sock *sk, int flags); 345 346 struct tls_record_info *tls_get_record(struct tls_offload_context_tx *context, 347 u32 seq, u64 *p_record_sn); 348 349 static inline bool tls_record_is_start_marker(struct tls_record_info *rec) 350 { 351 return rec->len == 0; 352 } 353 354 static inline u32 tls_record_start_seq(struct tls_record_info *rec) 355 { 356 return rec->end_seq - rec->len; 357 } 358 359 int tls_push_sg(struct sock *sk, struct tls_context *ctx, 360 struct scatterlist *sg, u16 first_offset, 361 int flags); 362 int tls_push_partial_record(struct sock *sk, struct tls_context *ctx, 363 int flags); 364 bool tls_free_partial_record(struct sock *sk, struct tls_context *ctx); 365 366 static inline struct tls_msg *tls_msg(struct sk_buff *skb) 367 { 368 return (struct tls_msg *)strp_msg(skb); 369 } 370 371 static inline bool tls_is_partially_sent_record(struct tls_context *ctx) 372 { 373 return !!ctx->partially_sent_record; 374 } 375 376 static inline int tls_complete_pending_work(struct sock *sk, 377 struct tls_context *ctx, 378 int flags, long *timeo) 379 { 380 int rc = 0; 381 382 if (unlikely(sk->sk_write_pending)) 383 rc = wait_on_pending_writer(sk, timeo); 384 385 if (!rc && tls_is_partially_sent_record(ctx)) 386 rc = tls_push_partial_record(sk, ctx, flags); 387 388 return rc; 389 } 390 391 static inline bool tls_is_pending_open_record(struct tls_context *tls_ctx) 392 { 393 return tls_ctx->pending_open_record_frags; 394 } 395 396 static inline bool is_tx_ready(struct tls_sw_context_tx *ctx) 397 { 398 struct tls_rec *rec; 399 400 rec = list_first_entry(&ctx->tx_list, struct tls_rec, list); 401 if (!rec) 402 return false; 403 404 return READ_ONCE(rec->tx_ready); 405 } 406 407 struct sk_buff * 408 tls_validate_xmit_skb(struct sock *sk, struct net_device *dev, 409 struct sk_buff *skb); 410 411 static inline bool tls_is_sk_tx_device_offloaded(struct sock *sk) 412 { 413 #ifdef CONFIG_SOCK_VALIDATE_XMIT 414 return sk_fullsock(sk) && 415 (smp_load_acquire(&sk->sk_validate_xmit_skb) == 416 &tls_validate_xmit_skb); 417 #else 418 return false; 419 #endif 420 } 421 422 static inline void tls_err_abort(struct sock *sk, int err) 423 { 424 sk->sk_err = err; 425 sk->sk_error_report(sk); 426 } 427 428 static inline bool tls_bigint_increment(unsigned char *seq, int len) 429 { 430 int i; 431 432 for (i = len - 1; i >= 0; i--) { 433 ++seq[i]; 434 if (seq[i] != 0) 435 break; 436 } 437 438 return (i == -1); 439 } 440 441 static inline struct tls_context *tls_get_ctx(const struct sock *sk) 442 { 443 struct inet_connection_sock *icsk = inet_csk(sk); 444 445 return icsk->icsk_ulp_data; 446 } 447 448 static inline void tls_advance_record_sn(struct sock *sk, 449 struct tls_prot_info *prot, 450 struct cipher_context *ctx) 451 { 452 if (tls_bigint_increment(ctx->rec_seq, prot->rec_seq_size)) 453 tls_err_abort(sk, EBADMSG); 454 455 if (prot->version != TLS_1_3_VERSION) 456 tls_bigint_increment(ctx->iv + TLS_CIPHER_AES_GCM_128_SALT_SIZE, 457 prot->iv_size); 458 } 459 460 static inline void tls_fill_prepend(struct tls_context *ctx, 461 char *buf, 462 size_t plaintext_len, 463 unsigned char record_type, 464 int version) 465 { 466 struct tls_prot_info *prot = &ctx->prot_info; 467 size_t pkt_len, iv_size = prot->iv_size; 468 469 pkt_len = plaintext_len + prot->tag_size; 470 if (version != TLS_1_3_VERSION) { 471 pkt_len += iv_size; 472 473 memcpy(buf + TLS_NONCE_OFFSET, 474 ctx->tx.iv + TLS_CIPHER_AES_GCM_128_SALT_SIZE, iv_size); 475 } 476 477 /* we cover nonce explicit here as well, so buf should be of 478 * size KTLS_DTLS_HEADER_SIZE + KTLS_DTLS_NONCE_EXPLICIT_SIZE 479 */ 480 buf[0] = version == TLS_1_3_VERSION ? 481 TLS_RECORD_TYPE_DATA : record_type; 482 /* Note that VERSION must be TLS_1_2 for both TLS1.2 and TLS1.3 */ 483 buf[1] = TLS_1_2_VERSION_MINOR; 484 buf[2] = TLS_1_2_VERSION_MAJOR; 485 /* we can use IV for nonce explicit according to spec */ 486 buf[3] = pkt_len >> 8; 487 buf[4] = pkt_len & 0xFF; 488 } 489 490 static inline void tls_make_aad(char *buf, 491 size_t size, 492 char *record_sequence, 493 int record_sequence_size, 494 unsigned char record_type, 495 int version) 496 { 497 if (version != TLS_1_3_VERSION) { 498 memcpy(buf, record_sequence, record_sequence_size); 499 buf += 8; 500 } else { 501 size += TLS_CIPHER_AES_GCM_128_TAG_SIZE; 502 } 503 504 buf[0] = version == TLS_1_3_VERSION ? 505 TLS_RECORD_TYPE_DATA : record_type; 506 buf[1] = TLS_1_2_VERSION_MAJOR; 507 buf[2] = TLS_1_2_VERSION_MINOR; 508 buf[3] = size >> 8; 509 buf[4] = size & 0xFF; 510 } 511 512 static inline void xor_iv_with_seq(int version, char *iv, char *seq) 513 { 514 int i; 515 516 if (version == TLS_1_3_VERSION) { 517 for (i = 0; i < 8; i++) 518 iv[i + 4] ^= seq[i]; 519 } 520 } 521 522 523 static inline struct tls_sw_context_rx *tls_sw_ctx_rx( 524 const struct tls_context *tls_ctx) 525 { 526 return (struct tls_sw_context_rx *)tls_ctx->priv_ctx_rx; 527 } 528 529 static inline struct tls_sw_context_tx *tls_sw_ctx_tx( 530 const struct tls_context *tls_ctx) 531 { 532 return (struct tls_sw_context_tx *)tls_ctx->priv_ctx_tx; 533 } 534 535 static inline struct tls_offload_context_tx * 536 tls_offload_ctx_tx(const struct tls_context *tls_ctx) 537 { 538 return (struct tls_offload_context_tx *)tls_ctx->priv_ctx_tx; 539 } 540 541 static inline bool tls_sw_has_ctx_tx(const struct sock *sk) 542 { 543 struct tls_context *ctx = tls_get_ctx(sk); 544 545 if (!ctx) 546 return false; 547 return !!tls_sw_ctx_tx(ctx); 548 } 549 550 void tls_sw_write_space(struct sock *sk, struct tls_context *ctx); 551 void tls_device_write_space(struct sock *sk, struct tls_context *ctx); 552 553 static inline struct tls_offload_context_rx * 554 tls_offload_ctx_rx(const struct tls_context *tls_ctx) 555 { 556 return (struct tls_offload_context_rx *)tls_ctx->priv_ctx_rx; 557 } 558 559 #if IS_ENABLED(CONFIG_TLS_DEVICE) 560 static inline void *__tls_driver_ctx(struct tls_context *tls_ctx, 561 enum tls_offload_ctx_dir direction) 562 { 563 if (direction == TLS_OFFLOAD_CTX_DIR_TX) 564 return tls_offload_ctx_tx(tls_ctx)->driver_state; 565 else 566 return tls_offload_ctx_rx(tls_ctx)->driver_state; 567 } 568 569 static inline void * 570 tls_driver_ctx(const struct sock *sk, enum tls_offload_ctx_dir direction) 571 { 572 return __tls_driver_ctx(tls_get_ctx(sk), direction); 573 } 574 #endif 575 576 /* The TLS context is valid until sk_destruct is called */ 577 static inline void tls_offload_rx_resync_request(struct sock *sk, __be32 seq) 578 { 579 struct tls_context *tls_ctx = tls_get_ctx(sk); 580 struct tls_offload_context_rx *rx_ctx = tls_offload_ctx_rx(tls_ctx); 581 582 atomic64_set(&rx_ctx->resync_req, ((u64)ntohl(seq) << 32) | 1); 583 } 584 585 586 int tls_proccess_cmsg(struct sock *sk, struct msghdr *msg, 587 unsigned char *record_type); 588 void tls_register_device(struct tls_device *device); 589 void tls_unregister_device(struct tls_device *device); 590 int tls_device_decrypted(struct sock *sk, struct sk_buff *skb); 591 int decrypt_skb(struct sock *sk, struct sk_buff *skb, 592 struct scatterlist *sgout); 593 594 struct sk_buff *tls_validate_xmit_skb(struct sock *sk, 595 struct net_device *dev, 596 struct sk_buff *skb); 597 598 int tls_sw_fallback_init(struct sock *sk, 599 struct tls_offload_context_tx *offload_ctx, 600 struct tls_crypto_info *crypto_info); 601 602 int tls_set_device_offload_rx(struct sock *sk, struct tls_context *ctx); 603 604 void tls_device_offload_cleanup_rx(struct sock *sk); 605 void handle_device_resync(struct sock *sk, u32 seq, u64 rcd_sn); 606 607 #endif /* _TLS_OFFLOAD_H */ 608