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 44 #include <net/tcp.h> 45 #include <net/strparser.h> 46 #include <crypto/aead.h> 47 #include <uapi/linux/tls.h> 48 49 50 /* Maximum data size carried in a TLS record */ 51 #define TLS_MAX_PAYLOAD_SIZE ((size_t)1 << 14) 52 53 #define TLS_HEADER_SIZE 5 54 #define TLS_NONCE_OFFSET TLS_HEADER_SIZE 55 56 #define TLS_CRYPTO_INFO_READY(info) ((info)->cipher_type) 57 58 #define TLS_RECORD_TYPE_DATA 0x17 59 60 #define TLS_AAD_SPACE_SIZE 13 61 #define TLS_DEVICE_NAME_MAX 32 62 63 #define MAX_IV_SIZE 16 64 65 /* For AES-CCM, the full 16-bytes of IV is made of '4' fields of given sizes. 66 * 67 * IV[16] = b0[1] || implicit nonce[4] || explicit nonce[8] || length[3] 68 * 69 * The field 'length' is encoded in field 'b0' as '(length width - 1)'. 70 * Hence b0 contains (3 - 1) = 2. 71 */ 72 #define TLS_AES_CCM_IV_B0_BYTE 2 73 74 /* 75 * This structure defines the routines for Inline TLS driver. 76 * The following routines are optional and filled with a 77 * null pointer if not defined. 78 * 79 * @name: Its the name of registered Inline tls device 80 * @dev_list: Inline tls device list 81 * int (*feature)(struct tls_device *device); 82 * Called to return Inline TLS driver capability 83 * 84 * int (*hash)(struct tls_device *device, struct sock *sk); 85 * This function sets Inline driver for listen and program 86 * device specific functioanlity as required 87 * 88 * void (*unhash)(struct tls_device *device, struct sock *sk); 89 * This function cleans listen state set by Inline TLS driver 90 * 91 * void (*release)(struct kref *kref); 92 * Release the registered device and allocated resources 93 * @kref: Number of reference to tls_device 94 */ 95 struct tls_device { 96 char name[TLS_DEVICE_NAME_MAX]; 97 struct list_head dev_list; 98 int (*feature)(struct tls_device *device); 99 int (*hash)(struct tls_device *device, struct sock *sk); 100 void (*unhash)(struct tls_device *device, struct sock *sk); 101 void (*release)(struct kref *kref); 102 struct kref kref; 103 }; 104 105 enum { 106 TLS_BASE, 107 TLS_SW, 108 #ifdef CONFIG_TLS_DEVICE 109 TLS_HW, 110 #endif 111 TLS_HW_RECORD, 112 TLS_NUM_CONFIG, 113 }; 114 115 /* TLS records are maintained in 'struct tls_rec'. It stores the memory pages 116 * allocated or mapped for each TLS record. After encryption, the records are 117 * stores in a linked list. 118 */ 119 struct tls_rec { 120 struct list_head list; 121 int tx_ready; 122 int tx_flags; 123 int inplace_crypto; 124 125 struct sk_msg msg_plaintext; 126 struct sk_msg msg_encrypted; 127 128 /* AAD | msg_plaintext.sg.data | sg_tag */ 129 struct scatterlist sg_aead_in[2]; 130 /* AAD | msg_encrypted.sg.data (data contains overhead for hdr & iv & tag) */ 131 struct scatterlist sg_aead_out[2]; 132 133 char content_type; 134 struct scatterlist sg_content_type; 135 136 char aad_space[TLS_AAD_SPACE_SIZE]; 137 u8 iv_data[MAX_IV_SIZE]; 138 struct aead_request aead_req; 139 u8 aead_req_ctx[]; 140 }; 141 142 struct tls_msg { 143 struct strp_msg rxm; 144 u8 control; 145 }; 146 147 struct tx_work { 148 struct delayed_work work; 149 struct sock *sk; 150 }; 151 152 struct tls_sw_context_tx { 153 struct crypto_aead *aead_send; 154 struct crypto_wait async_wait; 155 struct tx_work tx_work; 156 struct tls_rec *open_rec; 157 struct list_head tx_list; 158 atomic_t encrypt_pending; 159 int async_notify; 160 int async_capable; 161 162 #define BIT_TX_SCHEDULED 0 163 unsigned long tx_bitmask; 164 }; 165 166 struct tls_sw_context_rx { 167 struct crypto_aead *aead_recv; 168 struct crypto_wait async_wait; 169 struct strparser strp; 170 struct sk_buff_head rx_list; /* list of decrypted 'data' records */ 171 void (*saved_data_ready)(struct sock *sk); 172 173 struct sk_buff *recv_pkt; 174 u8 control; 175 int async_capable; 176 bool decrypted; 177 atomic_t decrypt_pending; 178 bool async_notify; 179 }; 180 181 struct tls_record_info { 182 struct list_head list; 183 u32 end_seq; 184 int len; 185 int num_frags; 186 skb_frag_t frags[MAX_SKB_FRAGS]; 187 }; 188 189 struct tls_offload_context_tx { 190 struct crypto_aead *aead_send; 191 spinlock_t lock; /* protects records list */ 192 struct list_head records_list; 193 struct tls_record_info *open_record; 194 struct tls_record_info *retransmit_hint; 195 u64 hint_record_sn; 196 u64 unacked_record_sn; 197 198 struct scatterlist sg_tx_data[MAX_SKB_FRAGS]; 199 void (*sk_destruct)(struct sock *sk); 200 u8 driver_state[]; 201 /* The TLS layer reserves room for driver specific state 202 * Currently the belief is that there is not enough 203 * driver specific state to justify another layer of indirection 204 */ 205 #define TLS_DRIVER_STATE_SIZE (max_t(size_t, 8, sizeof(void *))) 206 }; 207 208 #define TLS_OFFLOAD_CONTEXT_SIZE_TX \ 209 (ALIGN(sizeof(struct tls_offload_context_tx), sizeof(void *)) + \ 210 TLS_DRIVER_STATE_SIZE) 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 struct tls_prot_info prot_info; 244 245 union tls_crypto_context crypto_send; 246 union tls_crypto_context crypto_recv; 247 248 struct list_head list; 249 struct net_device *netdev; 250 refcount_t refcount; 251 252 void *priv_ctx_tx; 253 void *priv_ctx_rx; 254 255 u8 tx_conf:3; 256 u8 rx_conf:3; 257 258 struct cipher_context tx; 259 struct cipher_context rx; 260 261 struct scatterlist *partially_sent_record; 262 u16 partially_sent_offset; 263 264 unsigned long flags; 265 bool in_tcp_sendpages; 266 bool pending_open_record_frags; 267 268 int (*push_pending_record)(struct sock *sk, int flags); 269 270 void (*sk_write_space)(struct sock *sk); 271 void (*sk_destruct)(struct sock *sk); 272 void (*sk_proto_close)(struct sock *sk, long timeout); 273 274 int (*setsockopt)(struct sock *sk, int level, 275 int optname, char __user *optval, 276 unsigned int optlen); 277 int (*getsockopt)(struct sock *sk, int level, 278 int optname, char __user *optval, 279 int __user *optlen); 280 int (*hash)(struct sock *sk); 281 void (*unhash)(struct sock *sk); 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[]; 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 }; 311 312 #define TLS_OFFLOAD_CONTEXT_SIZE_RX \ 313 (ALIGN(sizeof(struct tls_offload_context_rx), sizeof(void *)) + \ 314 TLS_DRIVER_STATE_SIZE) 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 cipher_context *ctx, 450 int version) 451 { 452 struct tls_context *tls_ctx = tls_get_ctx(sk); 453 struct tls_prot_info *prot = &tls_ctx->prot_info; 454 455 if (tls_bigint_increment(ctx->rec_seq, prot->rec_seq_size)) 456 tls_err_abort(sk, EBADMSG); 457 458 if (version != TLS_1_3_VERSION) { 459 tls_bigint_increment(ctx->iv + TLS_CIPHER_AES_GCM_128_SALT_SIZE, 460 prot->iv_size); 461 } 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 /* The TLS context is valid until sk_destruct is called */ 564 static inline void tls_offload_rx_resync_request(struct sock *sk, __be32 seq) 565 { 566 struct tls_context *tls_ctx = tls_get_ctx(sk); 567 struct tls_offload_context_rx *rx_ctx = tls_offload_ctx_rx(tls_ctx); 568 569 atomic64_set(&rx_ctx->resync_req, ((u64)ntohl(seq) << 32) | 1); 570 } 571 572 573 int tls_proccess_cmsg(struct sock *sk, struct msghdr *msg, 574 unsigned char *record_type); 575 void tls_register_device(struct tls_device *device); 576 void tls_unregister_device(struct tls_device *device); 577 int tls_device_decrypted(struct sock *sk, struct sk_buff *skb); 578 int decrypt_skb(struct sock *sk, struct sk_buff *skb, 579 struct scatterlist *sgout); 580 581 struct sk_buff *tls_validate_xmit_skb(struct sock *sk, 582 struct net_device *dev, 583 struct sk_buff *skb); 584 585 int tls_sw_fallback_init(struct sock *sk, 586 struct tls_offload_context_tx *offload_ctx, 587 struct tls_crypto_info *crypto_info); 588 589 int tls_set_device_offload_rx(struct sock *sk, struct tls_context *ctx); 590 591 void tls_device_offload_cleanup_rx(struct sock *sk); 592 void handle_device_resync(struct sock *sk, u32 seq, u64 rcd_sn); 593 594 #endif /* _TLS_OFFLOAD_H */ 595