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_TX 16 206 }; 207 208 #define TLS_OFFLOAD_CONTEXT_SIZE_TX \ 209 (ALIGN(sizeof(struct tls_offload_context_tx), sizeof(void *)) + \ 210 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[]; 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 (ALIGN(sizeof(struct tls_offload_context_rx), sizeof(void *)) + \ 315 TLS_DRIVER_STATE_SIZE_RX) 316 317 int wait_on_pending_writer(struct sock *sk, long *timeo); 318 int tls_sk_query(struct sock *sk, int optname, char __user *optval, 319 int __user *optlen); 320 int tls_sk_attach(struct sock *sk, int optname, char __user *optval, 321 unsigned int optlen); 322 323 int tls_set_sw_offload(struct sock *sk, struct tls_context *ctx, int tx); 324 int tls_sw_sendmsg(struct sock *sk, struct msghdr *msg, size_t size); 325 int tls_sw_sendpage(struct sock *sk, struct page *page, 326 int offset, size_t size, int flags); 327 void tls_sw_close(struct sock *sk, long timeout); 328 void tls_sw_free_resources_tx(struct sock *sk); 329 void tls_sw_free_resources_rx(struct sock *sk); 330 void tls_sw_release_resources_rx(struct sock *sk); 331 int tls_sw_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, 332 int nonblock, int flags, int *addr_len); 333 bool tls_sw_stream_read(const struct sock *sk); 334 ssize_t tls_sw_splice_read(struct socket *sock, loff_t *ppos, 335 struct pipe_inode_info *pipe, 336 size_t len, unsigned int flags); 337 338 int tls_set_device_offload(struct sock *sk, struct tls_context *ctx); 339 int tls_device_sendmsg(struct sock *sk, struct msghdr *msg, size_t size); 340 int tls_device_sendpage(struct sock *sk, struct page *page, 341 int offset, size_t size, int flags); 342 void tls_device_free_resources_tx(struct sock *sk); 343 void tls_device_init(void); 344 void tls_device_cleanup(void); 345 int tls_tx_records(struct sock *sk, int flags); 346 347 struct tls_record_info *tls_get_record(struct tls_offload_context_tx *context, 348 u32 seq, u64 *p_record_sn); 349 350 static inline bool tls_record_is_start_marker(struct tls_record_info *rec) 351 { 352 return rec->len == 0; 353 } 354 355 static inline u32 tls_record_start_seq(struct tls_record_info *rec) 356 { 357 return rec->end_seq - rec->len; 358 } 359 360 int tls_push_sg(struct sock *sk, struct tls_context *ctx, 361 struct scatterlist *sg, u16 first_offset, 362 int flags); 363 int tls_push_partial_record(struct sock *sk, struct tls_context *ctx, 364 int flags); 365 bool tls_free_partial_record(struct sock *sk, struct tls_context *ctx); 366 367 static inline struct tls_msg *tls_msg(struct sk_buff *skb) 368 { 369 return (struct tls_msg *)strp_msg(skb); 370 } 371 372 static inline bool tls_is_partially_sent_record(struct tls_context *ctx) 373 { 374 return !!ctx->partially_sent_record; 375 } 376 377 static inline int tls_complete_pending_work(struct sock *sk, 378 struct tls_context *ctx, 379 int flags, long *timeo) 380 { 381 int rc = 0; 382 383 if (unlikely(sk->sk_write_pending)) 384 rc = wait_on_pending_writer(sk, timeo); 385 386 if (!rc && tls_is_partially_sent_record(ctx)) 387 rc = tls_push_partial_record(sk, ctx, flags); 388 389 return rc; 390 } 391 392 static inline bool tls_is_pending_open_record(struct tls_context *tls_ctx) 393 { 394 return tls_ctx->pending_open_record_frags; 395 } 396 397 static inline bool is_tx_ready(struct tls_sw_context_tx *ctx) 398 { 399 struct tls_rec *rec; 400 401 rec = list_first_entry(&ctx->tx_list, struct tls_rec, list); 402 if (!rec) 403 return false; 404 405 return READ_ONCE(rec->tx_ready); 406 } 407 408 struct sk_buff * 409 tls_validate_xmit_skb(struct sock *sk, struct net_device *dev, 410 struct sk_buff *skb); 411 412 static inline bool tls_is_sk_tx_device_offloaded(struct sock *sk) 413 { 414 #ifdef CONFIG_SOCK_VALIDATE_XMIT 415 return sk_fullsock(sk) && 416 (smp_load_acquire(&sk->sk_validate_xmit_skb) == 417 &tls_validate_xmit_skb); 418 #else 419 return false; 420 #endif 421 } 422 423 static inline void tls_err_abort(struct sock *sk, int err) 424 { 425 sk->sk_err = err; 426 sk->sk_error_report(sk); 427 } 428 429 static inline bool tls_bigint_increment(unsigned char *seq, int len) 430 { 431 int i; 432 433 for (i = len - 1; i >= 0; i--) { 434 ++seq[i]; 435 if (seq[i] != 0) 436 break; 437 } 438 439 return (i == -1); 440 } 441 442 static inline struct tls_context *tls_get_ctx(const struct sock *sk) 443 { 444 struct inet_connection_sock *icsk = inet_csk(sk); 445 446 return icsk->icsk_ulp_data; 447 } 448 449 static inline void tls_advance_record_sn(struct sock *sk, 450 struct tls_prot_info *prot, 451 struct cipher_context *ctx) 452 { 453 if (tls_bigint_increment(ctx->rec_seq, prot->rec_seq_size)) 454 tls_err_abort(sk, EBADMSG); 455 456 if (prot->version != TLS_1_3_VERSION) 457 tls_bigint_increment(ctx->iv + TLS_CIPHER_AES_GCM_128_SALT_SIZE, 458 prot->iv_size); 459 } 460 461 static inline void tls_fill_prepend(struct tls_context *ctx, 462 char *buf, 463 size_t plaintext_len, 464 unsigned char record_type, 465 int version) 466 { 467 struct tls_prot_info *prot = &ctx->prot_info; 468 size_t pkt_len, iv_size = prot->iv_size; 469 470 pkt_len = plaintext_len + prot->tag_size; 471 if (version != TLS_1_3_VERSION) { 472 pkt_len += iv_size; 473 474 memcpy(buf + TLS_NONCE_OFFSET, 475 ctx->tx.iv + TLS_CIPHER_AES_GCM_128_SALT_SIZE, iv_size); 476 } 477 478 /* we cover nonce explicit here as well, so buf should be of 479 * size KTLS_DTLS_HEADER_SIZE + KTLS_DTLS_NONCE_EXPLICIT_SIZE 480 */ 481 buf[0] = version == TLS_1_3_VERSION ? 482 TLS_RECORD_TYPE_DATA : record_type; 483 /* Note that VERSION must be TLS_1_2 for both TLS1.2 and TLS1.3 */ 484 buf[1] = TLS_1_2_VERSION_MINOR; 485 buf[2] = TLS_1_2_VERSION_MAJOR; 486 /* we can use IV for nonce explicit according to spec */ 487 buf[3] = pkt_len >> 8; 488 buf[4] = pkt_len & 0xFF; 489 } 490 491 static inline void tls_make_aad(char *buf, 492 size_t size, 493 char *record_sequence, 494 int record_sequence_size, 495 unsigned char record_type, 496 int version) 497 { 498 if (version != TLS_1_3_VERSION) { 499 memcpy(buf, record_sequence, record_sequence_size); 500 buf += 8; 501 } else { 502 size += TLS_CIPHER_AES_GCM_128_TAG_SIZE; 503 } 504 505 buf[0] = version == TLS_1_3_VERSION ? 506 TLS_RECORD_TYPE_DATA : record_type; 507 buf[1] = TLS_1_2_VERSION_MAJOR; 508 buf[2] = TLS_1_2_VERSION_MINOR; 509 buf[3] = size >> 8; 510 buf[4] = size & 0xFF; 511 } 512 513 static inline void xor_iv_with_seq(int version, char *iv, char *seq) 514 { 515 int i; 516 517 if (version == TLS_1_3_VERSION) { 518 for (i = 0; i < 8; i++) 519 iv[i + 4] ^= seq[i]; 520 } 521 } 522 523 524 static inline struct tls_sw_context_rx *tls_sw_ctx_rx( 525 const struct tls_context *tls_ctx) 526 { 527 return (struct tls_sw_context_rx *)tls_ctx->priv_ctx_rx; 528 } 529 530 static inline struct tls_sw_context_tx *tls_sw_ctx_tx( 531 const struct tls_context *tls_ctx) 532 { 533 return (struct tls_sw_context_tx *)tls_ctx->priv_ctx_tx; 534 } 535 536 static inline struct tls_offload_context_tx * 537 tls_offload_ctx_tx(const struct tls_context *tls_ctx) 538 { 539 return (struct tls_offload_context_tx *)tls_ctx->priv_ctx_tx; 540 } 541 542 static inline bool tls_sw_has_ctx_tx(const struct sock *sk) 543 { 544 struct tls_context *ctx = tls_get_ctx(sk); 545 546 if (!ctx) 547 return false; 548 return !!tls_sw_ctx_tx(ctx); 549 } 550 551 void tls_sw_write_space(struct sock *sk, struct tls_context *ctx); 552 void tls_device_write_space(struct sock *sk, struct tls_context *ctx); 553 554 static inline struct tls_offload_context_rx * 555 tls_offload_ctx_rx(const struct tls_context *tls_ctx) 556 { 557 return (struct tls_offload_context_rx *)tls_ctx->priv_ctx_rx; 558 } 559 560 /* The TLS context is valid until sk_destruct is called */ 561 static inline void tls_offload_rx_resync_request(struct sock *sk, __be32 seq) 562 { 563 struct tls_context *tls_ctx = tls_get_ctx(sk); 564 struct tls_offload_context_rx *rx_ctx = tls_offload_ctx_rx(tls_ctx); 565 566 atomic64_set(&rx_ctx->resync_req, ((u64)ntohl(seq) << 32) | 1); 567 } 568 569 570 int tls_proccess_cmsg(struct sock *sk, struct msghdr *msg, 571 unsigned char *record_type); 572 void tls_register_device(struct tls_device *device); 573 void tls_unregister_device(struct tls_device *device); 574 int tls_device_decrypted(struct sock *sk, struct sk_buff *skb); 575 int decrypt_skb(struct sock *sk, struct sk_buff *skb, 576 struct scatterlist *sgout); 577 578 struct sk_buff *tls_validate_xmit_skb(struct sock *sk, 579 struct net_device *dev, 580 struct sk_buff *skb); 581 582 int tls_sw_fallback_init(struct sock *sk, 583 struct tls_offload_context_tx *offload_ctx, 584 struct tls_crypto_info *crypto_info); 585 586 int tls_set_device_offload_rx(struct sock *sk, struct tls_context *ctx); 587 588 void tls_device_offload_cleanup_rx(struct sock *sk); 589 void handle_device_resync(struct sock *sk, u32 seq, u64 rcd_sn); 590 591 #endif /* _TLS_OFFLOAD_H */ 592