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 /* 64 * This structure defines the routines for Inline TLS driver. 65 * The following routines are optional and filled with a 66 * null pointer if not defined. 67 * 68 * @name: Its the name of registered Inline tls device 69 * @dev_list: Inline tls device list 70 * int (*feature)(struct tls_device *device); 71 * Called to return Inline TLS driver capability 72 * 73 * int (*hash)(struct tls_device *device, struct sock *sk); 74 * This function sets Inline driver for listen and program 75 * device specific functioanlity as required 76 * 77 * void (*unhash)(struct tls_device *device, struct sock *sk); 78 * This function cleans listen state set by Inline TLS driver 79 * 80 * void (*release)(struct kref *kref); 81 * Release the registered device and allocated resources 82 * @kref: Number of reference to tls_device 83 */ 84 struct tls_device { 85 char name[TLS_DEVICE_NAME_MAX]; 86 struct list_head dev_list; 87 int (*feature)(struct tls_device *device); 88 int (*hash)(struct tls_device *device, struct sock *sk); 89 void (*unhash)(struct tls_device *device, struct sock *sk); 90 void (*release)(struct kref *kref); 91 struct kref kref; 92 }; 93 94 enum { 95 TLS_BASE, 96 TLS_SW, 97 #ifdef CONFIG_TLS_DEVICE 98 TLS_HW, 99 #endif 100 TLS_HW_RECORD, 101 TLS_NUM_CONFIG, 102 }; 103 104 /* TLS records are maintained in 'struct tls_rec'. It stores the memory pages 105 * allocated or mapped for each TLS record. After encryption, the records are 106 * stores in a linked list. 107 */ 108 struct tls_rec { 109 struct list_head list; 110 int tx_ready; 111 int tx_flags; 112 int inplace_crypto; 113 114 struct sk_msg msg_plaintext; 115 struct sk_msg msg_encrypted; 116 117 /* AAD | msg_plaintext.sg.data | sg_tag */ 118 struct scatterlist sg_aead_in[2]; 119 /* AAD | msg_encrypted.sg.data (data contains overhead for hdr & iv & tag) */ 120 struct scatterlist sg_aead_out[2]; 121 122 char content_type; 123 struct scatterlist sg_content_type; 124 125 char aad_space[TLS_AAD_SPACE_SIZE]; 126 u8 iv_data[TLS_CIPHER_AES_GCM_128_IV_SIZE + 127 TLS_CIPHER_AES_GCM_128_SALT_SIZE]; 128 struct aead_request aead_req; 129 u8 aead_req_ctx[]; 130 }; 131 132 struct tls_msg { 133 struct strp_msg rxm; 134 u8 control; 135 }; 136 137 struct tx_work { 138 struct delayed_work work; 139 struct sock *sk; 140 }; 141 142 struct tls_sw_context_tx { 143 struct crypto_aead *aead_send; 144 struct crypto_wait async_wait; 145 struct tx_work tx_work; 146 struct tls_rec *open_rec; 147 struct list_head tx_list; 148 atomic_t encrypt_pending; 149 int async_notify; 150 int async_capable; 151 152 #define BIT_TX_SCHEDULED 0 153 unsigned long tx_bitmask; 154 }; 155 156 struct tls_sw_context_rx { 157 struct crypto_aead *aead_recv; 158 struct crypto_wait async_wait; 159 struct strparser strp; 160 struct sk_buff_head rx_list; /* list of decrypted 'data' records */ 161 void (*saved_data_ready)(struct sock *sk); 162 163 struct sk_buff *recv_pkt; 164 u8 control; 165 int async_capable; 166 bool decrypted; 167 atomic_t decrypt_pending; 168 bool async_notify; 169 }; 170 171 struct tls_record_info { 172 struct list_head list; 173 u32 end_seq; 174 int len; 175 int num_frags; 176 skb_frag_t frags[MAX_SKB_FRAGS]; 177 }; 178 179 struct tls_offload_context_tx { 180 struct crypto_aead *aead_send; 181 spinlock_t lock; /* protects records list */ 182 struct list_head records_list; 183 struct tls_record_info *open_record; 184 struct tls_record_info *retransmit_hint; 185 u64 hint_record_sn; 186 u64 unacked_record_sn; 187 188 struct scatterlist sg_tx_data[MAX_SKB_FRAGS]; 189 void (*sk_destruct)(struct sock *sk); 190 u8 driver_state[]; 191 /* The TLS layer reserves room for driver specific state 192 * Currently the belief is that there is not enough 193 * driver specific state to justify another layer of indirection 194 */ 195 #define TLS_DRIVER_STATE_SIZE (max_t(size_t, 8, sizeof(void *))) 196 }; 197 198 #define TLS_OFFLOAD_CONTEXT_SIZE_TX \ 199 (ALIGN(sizeof(struct tls_offload_context_tx), sizeof(void *)) + \ 200 TLS_DRIVER_STATE_SIZE) 201 202 struct cipher_context { 203 char *iv; 204 char *rec_seq; 205 }; 206 207 union tls_crypto_context { 208 struct tls_crypto_info info; 209 union { 210 struct tls12_crypto_info_aes_gcm_128 aes_gcm_128; 211 struct tls12_crypto_info_aes_gcm_256 aes_gcm_256; 212 }; 213 }; 214 215 struct tls_prot_info { 216 u16 version; 217 u16 cipher_type; 218 u16 prepend_size; 219 u16 tag_size; 220 u16 overhead_size; 221 u16 iv_size; 222 u16 rec_seq_size; 223 u16 aad_size; 224 u16 tail_size; 225 }; 226 227 struct tls_context { 228 struct tls_prot_info prot_info; 229 230 union tls_crypto_context crypto_send; 231 union tls_crypto_context crypto_recv; 232 233 struct list_head list; 234 struct net_device *netdev; 235 refcount_t refcount; 236 237 void *priv_ctx_tx; 238 void *priv_ctx_rx; 239 240 u8 tx_conf:3; 241 u8 rx_conf:3; 242 243 struct cipher_context tx; 244 struct cipher_context rx; 245 246 struct scatterlist *partially_sent_record; 247 u16 partially_sent_offset; 248 249 unsigned long flags; 250 bool in_tcp_sendpages; 251 bool pending_open_record_frags; 252 253 int (*push_pending_record)(struct sock *sk, int flags); 254 255 void (*sk_write_space)(struct sock *sk); 256 void (*sk_destruct)(struct sock *sk); 257 void (*sk_proto_close)(struct sock *sk, long timeout); 258 259 int (*setsockopt)(struct sock *sk, int level, 260 int optname, char __user *optval, 261 unsigned int optlen); 262 int (*getsockopt)(struct sock *sk, int level, 263 int optname, char __user *optval, 264 int __user *optlen); 265 int (*hash)(struct sock *sk); 266 void (*unhash)(struct sock *sk); 267 }; 268 269 struct tls_offload_context_rx { 270 /* sw must be the first member of tls_offload_context_rx */ 271 struct tls_sw_context_rx sw; 272 atomic64_t resync_req; 273 u8 driver_state[]; 274 /* The TLS layer reserves room for driver specific state 275 * Currently the belief is that there is not enough 276 * driver specific state to justify another layer of indirection 277 */ 278 }; 279 280 #define TLS_OFFLOAD_CONTEXT_SIZE_RX \ 281 (ALIGN(sizeof(struct tls_offload_context_rx), sizeof(void *)) + \ 282 TLS_DRIVER_STATE_SIZE) 283 284 int wait_on_pending_writer(struct sock *sk, long *timeo); 285 int tls_sk_query(struct sock *sk, int optname, char __user *optval, 286 int __user *optlen); 287 int tls_sk_attach(struct sock *sk, int optname, char __user *optval, 288 unsigned int optlen); 289 290 int tls_set_sw_offload(struct sock *sk, struct tls_context *ctx, int tx); 291 int tls_sw_sendmsg(struct sock *sk, struct msghdr *msg, size_t size); 292 int tls_sw_sendpage(struct sock *sk, struct page *page, 293 int offset, size_t size, int flags); 294 void tls_sw_close(struct sock *sk, long timeout); 295 void tls_sw_free_resources_tx(struct sock *sk); 296 void tls_sw_free_resources_rx(struct sock *sk); 297 void tls_sw_release_resources_rx(struct sock *sk); 298 int tls_sw_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, 299 int nonblock, int flags, int *addr_len); 300 bool tls_sw_stream_read(const struct sock *sk); 301 ssize_t tls_sw_splice_read(struct socket *sock, loff_t *ppos, 302 struct pipe_inode_info *pipe, 303 size_t len, unsigned int flags); 304 305 int tls_set_device_offload(struct sock *sk, struct tls_context *ctx); 306 int tls_device_sendmsg(struct sock *sk, struct msghdr *msg, size_t size); 307 int tls_device_sendpage(struct sock *sk, struct page *page, 308 int offset, size_t size, int flags); 309 void tls_device_sk_destruct(struct sock *sk); 310 void tls_device_free_resources_tx(struct sock *sk); 311 void tls_device_init(void); 312 void tls_device_cleanup(void); 313 int tls_tx_records(struct sock *sk, int flags); 314 315 struct tls_record_info *tls_get_record(struct tls_offload_context_tx *context, 316 u32 seq, u64 *p_record_sn); 317 318 static inline bool tls_record_is_start_marker(struct tls_record_info *rec) 319 { 320 return rec->len == 0; 321 } 322 323 static inline u32 tls_record_start_seq(struct tls_record_info *rec) 324 { 325 return rec->end_seq - rec->len; 326 } 327 328 void tls_sk_destruct(struct sock *sk, struct tls_context *ctx); 329 int tls_push_sg(struct sock *sk, struct tls_context *ctx, 330 struct scatterlist *sg, u16 first_offset, 331 int flags); 332 int tls_push_partial_record(struct sock *sk, struct tls_context *ctx, 333 int flags); 334 bool tls_free_partial_record(struct sock *sk, struct tls_context *ctx); 335 336 static inline struct tls_msg *tls_msg(struct sk_buff *skb) 337 { 338 return (struct tls_msg *)strp_msg(skb); 339 } 340 341 static inline bool tls_is_partially_sent_record(struct tls_context *ctx) 342 { 343 return !!ctx->partially_sent_record; 344 } 345 346 static inline int tls_complete_pending_work(struct sock *sk, 347 struct tls_context *ctx, 348 int flags, long *timeo) 349 { 350 int rc = 0; 351 352 if (unlikely(sk->sk_write_pending)) 353 rc = wait_on_pending_writer(sk, timeo); 354 355 if (!rc && tls_is_partially_sent_record(ctx)) 356 rc = tls_push_partial_record(sk, ctx, flags); 357 358 return rc; 359 } 360 361 static inline bool tls_is_pending_open_record(struct tls_context *tls_ctx) 362 { 363 return tls_ctx->pending_open_record_frags; 364 } 365 366 static inline bool is_tx_ready(struct tls_sw_context_tx *ctx) 367 { 368 struct tls_rec *rec; 369 370 rec = list_first_entry(&ctx->tx_list, struct tls_rec, list); 371 if (!rec) 372 return false; 373 374 return READ_ONCE(rec->tx_ready); 375 } 376 377 struct sk_buff * 378 tls_validate_xmit_skb(struct sock *sk, struct net_device *dev, 379 struct sk_buff *skb); 380 381 static inline bool tls_is_sk_tx_device_offloaded(struct sock *sk) 382 { 383 #ifdef CONFIG_SOCK_VALIDATE_XMIT 384 return sk_fullsock(sk) && 385 (smp_load_acquire(&sk->sk_validate_xmit_skb) == 386 &tls_validate_xmit_skb); 387 #else 388 return false; 389 #endif 390 } 391 392 static inline void tls_err_abort(struct sock *sk, int err) 393 { 394 sk->sk_err = err; 395 sk->sk_error_report(sk); 396 } 397 398 static inline bool tls_bigint_increment(unsigned char *seq, int len) 399 { 400 int i; 401 402 for (i = len - 1; i >= 0; i--) { 403 ++seq[i]; 404 if (seq[i] != 0) 405 break; 406 } 407 408 return (i == -1); 409 } 410 411 static inline struct tls_context *tls_get_ctx(const struct sock *sk) 412 { 413 struct inet_connection_sock *icsk = inet_csk(sk); 414 415 return icsk->icsk_ulp_data; 416 } 417 418 static inline void tls_advance_record_sn(struct sock *sk, 419 struct cipher_context *ctx, 420 int version) 421 { 422 struct tls_context *tls_ctx = tls_get_ctx(sk); 423 struct tls_prot_info *prot = &tls_ctx->prot_info; 424 425 if (tls_bigint_increment(ctx->rec_seq, prot->rec_seq_size)) 426 tls_err_abort(sk, EBADMSG); 427 428 if (version != TLS_1_3_VERSION) { 429 tls_bigint_increment(ctx->iv + TLS_CIPHER_AES_GCM_128_SALT_SIZE, 430 prot->iv_size); 431 } 432 } 433 434 static inline void tls_fill_prepend(struct tls_context *ctx, 435 char *buf, 436 size_t plaintext_len, 437 unsigned char record_type, 438 int version) 439 { 440 struct tls_prot_info *prot = &ctx->prot_info; 441 size_t pkt_len, iv_size = prot->iv_size; 442 443 pkt_len = plaintext_len + prot->tag_size; 444 if (version != TLS_1_3_VERSION) { 445 pkt_len += iv_size; 446 447 memcpy(buf + TLS_NONCE_OFFSET, 448 ctx->tx.iv + TLS_CIPHER_AES_GCM_128_SALT_SIZE, iv_size); 449 } 450 451 /* we cover nonce explicit here as well, so buf should be of 452 * size KTLS_DTLS_HEADER_SIZE + KTLS_DTLS_NONCE_EXPLICIT_SIZE 453 */ 454 buf[0] = version == TLS_1_3_VERSION ? 455 TLS_RECORD_TYPE_DATA : record_type; 456 /* Note that VERSION must be TLS_1_2 for both TLS1.2 and TLS1.3 */ 457 buf[1] = TLS_1_2_VERSION_MINOR; 458 buf[2] = TLS_1_2_VERSION_MAJOR; 459 /* we can use IV for nonce explicit according to spec */ 460 buf[3] = pkt_len >> 8; 461 buf[4] = pkt_len & 0xFF; 462 } 463 464 static inline void tls_make_aad(char *buf, 465 size_t size, 466 char *record_sequence, 467 int record_sequence_size, 468 unsigned char record_type, 469 int version) 470 { 471 if (version != TLS_1_3_VERSION) { 472 memcpy(buf, record_sequence, record_sequence_size); 473 buf += 8; 474 } else { 475 size += TLS_CIPHER_AES_GCM_128_TAG_SIZE; 476 } 477 478 buf[0] = version == TLS_1_3_VERSION ? 479 TLS_RECORD_TYPE_DATA : record_type; 480 buf[1] = TLS_1_2_VERSION_MAJOR; 481 buf[2] = TLS_1_2_VERSION_MINOR; 482 buf[3] = size >> 8; 483 buf[4] = size & 0xFF; 484 } 485 486 static inline void xor_iv_with_seq(int version, char *iv, char *seq) 487 { 488 int i; 489 490 if (version == TLS_1_3_VERSION) { 491 for (i = 0; i < 8; i++) 492 iv[i + 4] ^= seq[i]; 493 } 494 } 495 496 497 static inline struct tls_sw_context_rx *tls_sw_ctx_rx( 498 const struct tls_context *tls_ctx) 499 { 500 return (struct tls_sw_context_rx *)tls_ctx->priv_ctx_rx; 501 } 502 503 static inline struct tls_sw_context_tx *tls_sw_ctx_tx( 504 const struct tls_context *tls_ctx) 505 { 506 return (struct tls_sw_context_tx *)tls_ctx->priv_ctx_tx; 507 } 508 509 static inline struct tls_offload_context_tx * 510 tls_offload_ctx_tx(const struct tls_context *tls_ctx) 511 { 512 return (struct tls_offload_context_tx *)tls_ctx->priv_ctx_tx; 513 } 514 515 static inline bool tls_sw_has_ctx_tx(const struct sock *sk) 516 { 517 struct tls_context *ctx = tls_get_ctx(sk); 518 519 if (!ctx) 520 return false; 521 return !!tls_sw_ctx_tx(ctx); 522 } 523 524 void tls_sw_write_space(struct sock *sk, struct tls_context *ctx); 525 void tls_device_write_space(struct sock *sk, struct tls_context *ctx); 526 527 static inline struct tls_offload_context_rx * 528 tls_offload_ctx_rx(const struct tls_context *tls_ctx) 529 { 530 return (struct tls_offload_context_rx *)tls_ctx->priv_ctx_rx; 531 } 532 533 /* The TLS context is valid until sk_destruct is called */ 534 static inline void tls_offload_rx_resync_request(struct sock *sk, __be32 seq) 535 { 536 struct tls_context *tls_ctx = tls_get_ctx(sk); 537 struct tls_offload_context_rx *rx_ctx = tls_offload_ctx_rx(tls_ctx); 538 539 atomic64_set(&rx_ctx->resync_req, ((((uint64_t)seq) << 32) | 1)); 540 } 541 542 543 int tls_proccess_cmsg(struct sock *sk, struct msghdr *msg, 544 unsigned char *record_type); 545 void tls_register_device(struct tls_device *device); 546 void tls_unregister_device(struct tls_device *device); 547 int tls_device_decrypted(struct sock *sk, struct sk_buff *skb); 548 int decrypt_skb(struct sock *sk, struct sk_buff *skb, 549 struct scatterlist *sgout); 550 551 struct sk_buff *tls_validate_xmit_skb(struct sock *sk, 552 struct net_device *dev, 553 struct sk_buff *skb); 554 555 int tls_sw_fallback_init(struct sock *sk, 556 struct tls_offload_context_tx *offload_ctx, 557 struct tls_crypto_info *crypto_info); 558 559 int tls_set_device_offload_rx(struct sock *sk, struct tls_context *ctx); 560 561 void tls_device_offload_cleanup_rx(struct sock *sk); 562 void handle_device_resync(struct sock *sk, u32 seq, u64 rcd_sn); 563 564 #endif /* _TLS_OFFLOAD_H */ 565