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 aad_space[TLS_AAD_SPACE_SIZE]; 123 struct aead_request aead_req; 124 u8 aead_req_ctx[]; 125 }; 126 127 struct tx_work { 128 struct delayed_work work; 129 struct sock *sk; 130 }; 131 132 struct tls_sw_context_tx { 133 struct crypto_aead *aead_send; 134 struct crypto_wait async_wait; 135 struct tx_work tx_work; 136 struct tls_rec *open_rec; 137 struct list_head tx_list; 138 atomic_t encrypt_pending; 139 int async_notify; 140 141 #define BIT_TX_SCHEDULED 0 142 unsigned long tx_bitmask; 143 }; 144 145 struct tls_sw_context_rx { 146 struct crypto_aead *aead_recv; 147 struct crypto_wait async_wait; 148 149 struct strparser strp; 150 void (*saved_data_ready)(struct sock *sk); 151 152 struct sk_buff *recv_pkt; 153 u8 control; 154 bool decrypted; 155 atomic_t decrypt_pending; 156 bool async_notify; 157 }; 158 159 struct tls_record_info { 160 struct list_head list; 161 u32 end_seq; 162 int len; 163 int num_frags; 164 skb_frag_t frags[MAX_SKB_FRAGS]; 165 }; 166 167 struct tls_offload_context_tx { 168 struct crypto_aead *aead_send; 169 spinlock_t lock; /* protects records list */ 170 struct list_head records_list; 171 struct tls_record_info *open_record; 172 struct tls_record_info *retransmit_hint; 173 u64 hint_record_sn; 174 u64 unacked_record_sn; 175 176 struct scatterlist sg_tx_data[MAX_SKB_FRAGS]; 177 void (*sk_destruct)(struct sock *sk); 178 u8 driver_state[]; 179 /* The TLS layer reserves room for driver specific state 180 * Currently the belief is that there is not enough 181 * driver specific state to justify another layer of indirection 182 */ 183 #define TLS_DRIVER_STATE_SIZE (max_t(size_t, 8, sizeof(void *))) 184 }; 185 186 #define TLS_OFFLOAD_CONTEXT_SIZE_TX \ 187 (ALIGN(sizeof(struct tls_offload_context_tx), sizeof(void *)) + \ 188 TLS_DRIVER_STATE_SIZE) 189 190 enum { 191 TLS_PENDING_CLOSED_RECORD 192 }; 193 194 struct cipher_context { 195 u16 prepend_size; 196 u16 tag_size; 197 u16 overhead_size; 198 u16 iv_size; 199 char *iv; 200 u16 rec_seq_size; 201 char *rec_seq; 202 }; 203 204 union tls_crypto_context { 205 struct tls_crypto_info info; 206 struct tls12_crypto_info_aes_gcm_128 aes_gcm_128; 207 }; 208 209 struct tls_context { 210 union tls_crypto_context crypto_send; 211 union tls_crypto_context crypto_recv; 212 213 struct list_head list; 214 struct net_device *netdev; 215 refcount_t refcount; 216 217 void *priv_ctx_tx; 218 void *priv_ctx_rx; 219 220 u8 tx_conf:3; 221 u8 rx_conf:3; 222 223 struct cipher_context tx; 224 struct cipher_context rx; 225 226 struct scatterlist *partially_sent_record; 227 u16 partially_sent_offset; 228 229 unsigned long flags; 230 bool in_tcp_sendpages; 231 bool pending_open_record_frags; 232 233 int (*push_pending_record)(struct sock *sk, int flags); 234 235 void (*sk_write_space)(struct sock *sk); 236 void (*sk_destruct)(struct sock *sk); 237 void (*sk_proto_close)(struct sock *sk, long timeout); 238 239 int (*setsockopt)(struct sock *sk, int level, 240 int optname, char __user *optval, 241 unsigned int optlen); 242 int (*getsockopt)(struct sock *sk, int level, 243 int optname, char __user *optval, 244 int __user *optlen); 245 int (*hash)(struct sock *sk); 246 void (*unhash)(struct sock *sk); 247 }; 248 249 struct tls_offload_context_rx { 250 /* sw must be the first member of tls_offload_context_rx */ 251 struct tls_sw_context_rx sw; 252 atomic64_t resync_req; 253 u8 driver_state[]; 254 /* The TLS layer reserves room for driver specific state 255 * Currently the belief is that there is not enough 256 * driver specific state to justify another layer of indirection 257 */ 258 }; 259 260 #define TLS_OFFLOAD_CONTEXT_SIZE_RX \ 261 (ALIGN(sizeof(struct tls_offload_context_rx), sizeof(void *)) + \ 262 TLS_DRIVER_STATE_SIZE) 263 264 int wait_on_pending_writer(struct sock *sk, long *timeo); 265 int tls_sk_query(struct sock *sk, int optname, char __user *optval, 266 int __user *optlen); 267 int tls_sk_attach(struct sock *sk, int optname, char __user *optval, 268 unsigned int optlen); 269 270 int tls_set_sw_offload(struct sock *sk, struct tls_context *ctx, int tx); 271 int tls_sw_sendmsg(struct sock *sk, struct msghdr *msg, size_t size); 272 int tls_sw_sendpage(struct sock *sk, struct page *page, 273 int offset, size_t size, int flags); 274 void tls_sw_close(struct sock *sk, long timeout); 275 void tls_sw_free_resources_tx(struct sock *sk); 276 void tls_sw_free_resources_rx(struct sock *sk); 277 void tls_sw_release_resources_rx(struct sock *sk); 278 int tls_sw_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, 279 int nonblock, int flags, int *addr_len); 280 bool tls_sw_stream_read(const struct sock *sk); 281 ssize_t tls_sw_splice_read(struct socket *sock, loff_t *ppos, 282 struct pipe_inode_info *pipe, 283 size_t len, unsigned int flags); 284 285 int tls_set_device_offload(struct sock *sk, struct tls_context *ctx); 286 int tls_device_sendmsg(struct sock *sk, struct msghdr *msg, size_t size); 287 int tls_device_sendpage(struct sock *sk, struct page *page, 288 int offset, size_t size, int flags); 289 void tls_device_sk_destruct(struct sock *sk); 290 void tls_device_init(void); 291 void tls_device_cleanup(void); 292 int tls_tx_records(struct sock *sk, int flags); 293 294 struct tls_record_info *tls_get_record(struct tls_offload_context_tx *context, 295 u32 seq, u64 *p_record_sn); 296 297 static inline bool tls_record_is_start_marker(struct tls_record_info *rec) 298 { 299 return rec->len == 0; 300 } 301 302 static inline u32 tls_record_start_seq(struct tls_record_info *rec) 303 { 304 return rec->end_seq - rec->len; 305 } 306 307 void tls_sk_destruct(struct sock *sk, struct tls_context *ctx); 308 int tls_push_sg(struct sock *sk, struct tls_context *ctx, 309 struct scatterlist *sg, u16 first_offset, 310 int flags); 311 int tls_push_partial_record(struct sock *sk, struct tls_context *ctx, 312 int flags); 313 314 int tls_push_pending_closed_record(struct sock *sk, struct tls_context *ctx, 315 int flags, long *timeo); 316 317 static inline bool tls_is_pending_closed_record(struct tls_context *ctx) 318 { 319 return test_bit(TLS_PENDING_CLOSED_RECORD, &ctx->flags); 320 } 321 322 static inline int tls_complete_pending_work(struct sock *sk, 323 struct tls_context *ctx, 324 int flags, long *timeo) 325 { 326 int rc = 0; 327 328 if (unlikely(sk->sk_write_pending)) 329 rc = wait_on_pending_writer(sk, timeo); 330 331 if (!rc && tls_is_pending_closed_record(ctx)) 332 rc = tls_push_pending_closed_record(sk, ctx, flags, timeo); 333 334 return rc; 335 } 336 337 static inline bool tls_is_partially_sent_record(struct tls_context *ctx) 338 { 339 return !!ctx->partially_sent_record; 340 } 341 342 static inline bool tls_is_pending_open_record(struct tls_context *tls_ctx) 343 { 344 return tls_ctx->pending_open_record_frags; 345 } 346 347 static inline bool is_tx_ready(struct tls_sw_context_tx *ctx) 348 { 349 struct tls_rec *rec; 350 351 rec = list_first_entry(&ctx->tx_list, struct tls_rec, list); 352 if (!rec) 353 return false; 354 355 return READ_ONCE(rec->tx_ready); 356 } 357 358 struct sk_buff * 359 tls_validate_xmit_skb(struct sock *sk, struct net_device *dev, 360 struct sk_buff *skb); 361 362 static inline bool tls_is_sk_tx_device_offloaded(struct sock *sk) 363 { 364 #ifdef CONFIG_SOCK_VALIDATE_XMIT 365 return sk_fullsock(sk) & 366 (smp_load_acquire(&sk->sk_validate_xmit_skb) == 367 &tls_validate_xmit_skb); 368 #else 369 return false; 370 #endif 371 } 372 373 static inline void tls_err_abort(struct sock *sk, int err) 374 { 375 sk->sk_err = err; 376 sk->sk_error_report(sk); 377 } 378 379 static inline bool tls_bigint_increment(unsigned char *seq, int len) 380 { 381 int i; 382 383 for (i = len - 1; i >= 0; i--) { 384 ++seq[i]; 385 if (seq[i] != 0) 386 break; 387 } 388 389 return (i == -1); 390 } 391 392 static inline void tls_advance_record_sn(struct sock *sk, 393 struct cipher_context *ctx) 394 { 395 if (tls_bigint_increment(ctx->rec_seq, ctx->rec_seq_size)) 396 tls_err_abort(sk, EBADMSG); 397 tls_bigint_increment(ctx->iv + TLS_CIPHER_AES_GCM_128_SALT_SIZE, 398 ctx->iv_size); 399 } 400 401 static inline void tls_fill_prepend(struct tls_context *ctx, 402 char *buf, 403 size_t plaintext_len, 404 unsigned char record_type) 405 { 406 size_t pkt_len, iv_size = ctx->tx.iv_size; 407 408 pkt_len = plaintext_len + iv_size + ctx->tx.tag_size; 409 410 /* we cover nonce explicit here as well, so buf should be of 411 * size KTLS_DTLS_HEADER_SIZE + KTLS_DTLS_NONCE_EXPLICIT_SIZE 412 */ 413 buf[0] = record_type; 414 buf[1] = TLS_VERSION_MINOR(ctx->crypto_send.info.version); 415 buf[2] = TLS_VERSION_MAJOR(ctx->crypto_send.info.version); 416 /* we can use IV for nonce explicit according to spec */ 417 buf[3] = pkt_len >> 8; 418 buf[4] = pkt_len & 0xFF; 419 memcpy(buf + TLS_NONCE_OFFSET, 420 ctx->tx.iv + TLS_CIPHER_AES_GCM_128_SALT_SIZE, iv_size); 421 } 422 423 static inline void tls_make_aad(char *buf, 424 size_t size, 425 char *record_sequence, 426 int record_sequence_size, 427 unsigned char record_type) 428 { 429 memcpy(buf, record_sequence, record_sequence_size); 430 431 buf[8] = record_type; 432 buf[9] = TLS_1_2_VERSION_MAJOR; 433 buf[10] = TLS_1_2_VERSION_MINOR; 434 buf[11] = size >> 8; 435 buf[12] = size & 0xFF; 436 } 437 438 static inline struct tls_context *tls_get_ctx(const struct sock *sk) 439 { 440 struct inet_connection_sock *icsk = inet_csk(sk); 441 442 return icsk->icsk_ulp_data; 443 } 444 445 static inline struct tls_sw_context_rx *tls_sw_ctx_rx( 446 const struct tls_context *tls_ctx) 447 { 448 return (struct tls_sw_context_rx *)tls_ctx->priv_ctx_rx; 449 } 450 451 static inline struct tls_sw_context_tx *tls_sw_ctx_tx( 452 const struct tls_context *tls_ctx) 453 { 454 return (struct tls_sw_context_tx *)tls_ctx->priv_ctx_tx; 455 } 456 457 static inline struct tls_offload_context_tx * 458 tls_offload_ctx_tx(const struct tls_context *tls_ctx) 459 { 460 return (struct tls_offload_context_tx *)tls_ctx->priv_ctx_tx; 461 } 462 463 static inline bool tls_sw_has_ctx_tx(const struct sock *sk) 464 { 465 struct tls_context *ctx = tls_get_ctx(sk); 466 467 if (!ctx) 468 return false; 469 return !!tls_sw_ctx_tx(ctx); 470 } 471 472 static inline struct tls_offload_context_rx * 473 tls_offload_ctx_rx(const struct tls_context *tls_ctx) 474 { 475 return (struct tls_offload_context_rx *)tls_ctx->priv_ctx_rx; 476 } 477 478 /* The TLS context is valid until sk_destruct is called */ 479 static inline void tls_offload_rx_resync_request(struct sock *sk, __be32 seq) 480 { 481 struct tls_context *tls_ctx = tls_get_ctx(sk); 482 struct tls_offload_context_rx *rx_ctx = tls_offload_ctx_rx(tls_ctx); 483 484 atomic64_set(&rx_ctx->resync_req, ((((uint64_t)seq) << 32) | 1)); 485 } 486 487 488 int tls_proccess_cmsg(struct sock *sk, struct msghdr *msg, 489 unsigned char *record_type); 490 void tls_register_device(struct tls_device *device); 491 void tls_unregister_device(struct tls_device *device); 492 int tls_device_decrypted(struct sock *sk, struct sk_buff *skb); 493 int decrypt_skb(struct sock *sk, struct sk_buff *skb, 494 struct scatterlist *sgout); 495 496 struct sk_buff *tls_validate_xmit_skb(struct sock *sk, 497 struct net_device *dev, 498 struct sk_buff *skb); 499 500 int tls_sw_fallback_init(struct sock *sk, 501 struct tls_offload_context_tx *offload_ctx, 502 struct tls_crypto_info *crypto_info); 503 504 int tls_set_device_offload_rx(struct sock *sk, struct tls_context *ctx); 505 506 void tls_device_offload_cleanup_rx(struct sock *sk); 507 void handle_device_resync(struct sock *sk, u32 seq, u64 rcd_sn); 508 509 #endif /* _TLS_OFFLOAD_H */ 510