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 struct strparser strp; 149 struct sk_buff_head rx_list; /* list of decrypted 'data' records */ 150 void (*saved_data_ready)(struct sock *sk); 151 152 struct sk_buff *recv_pkt; 153 u8 control; 154 int async_capable; 155 bool decrypted; 156 atomic_t decrypt_pending; 157 bool async_notify; 158 }; 159 160 struct tls_record_info { 161 struct list_head list; 162 u32 end_seq; 163 int len; 164 int num_frags; 165 skb_frag_t frags[MAX_SKB_FRAGS]; 166 }; 167 168 struct tls_offload_context_tx { 169 struct crypto_aead *aead_send; 170 spinlock_t lock; /* protects records list */ 171 struct list_head records_list; 172 struct tls_record_info *open_record; 173 struct tls_record_info *retransmit_hint; 174 u64 hint_record_sn; 175 u64 unacked_record_sn; 176 177 struct scatterlist sg_tx_data[MAX_SKB_FRAGS]; 178 void (*sk_destruct)(struct sock *sk); 179 u8 driver_state[]; 180 /* The TLS layer reserves room for driver specific state 181 * Currently the belief is that there is not enough 182 * driver specific state to justify another layer of indirection 183 */ 184 #define TLS_DRIVER_STATE_SIZE (max_t(size_t, 8, sizeof(void *))) 185 }; 186 187 #define TLS_OFFLOAD_CONTEXT_SIZE_TX \ 188 (ALIGN(sizeof(struct tls_offload_context_tx), sizeof(void *)) + \ 189 TLS_DRIVER_STATE_SIZE) 190 191 enum { 192 TLS_PENDING_CLOSED_RECORD 193 }; 194 195 struct cipher_context { 196 u16 prepend_size; 197 u16 tag_size; 198 u16 overhead_size; 199 u16 iv_size; 200 char *iv; 201 u16 rec_seq_size; 202 char *rec_seq; 203 }; 204 205 union tls_crypto_context { 206 struct tls_crypto_info info; 207 struct tls12_crypto_info_aes_gcm_128 aes_gcm_128; 208 }; 209 210 struct tls_context { 211 union tls_crypto_context crypto_send; 212 union tls_crypto_context crypto_recv; 213 214 struct list_head list; 215 struct net_device *netdev; 216 refcount_t refcount; 217 218 void *priv_ctx_tx; 219 void *priv_ctx_rx; 220 221 u8 tx_conf:3; 222 u8 rx_conf:3; 223 224 struct cipher_context tx; 225 struct cipher_context rx; 226 227 struct scatterlist *partially_sent_record; 228 u16 partially_sent_offset; 229 230 unsigned long flags; 231 bool in_tcp_sendpages; 232 bool pending_open_record_frags; 233 234 int (*push_pending_record)(struct sock *sk, int flags); 235 236 void (*sk_write_space)(struct sock *sk); 237 void (*sk_destruct)(struct sock *sk); 238 void (*sk_proto_close)(struct sock *sk, long timeout); 239 240 int (*setsockopt)(struct sock *sk, int level, 241 int optname, char __user *optval, 242 unsigned int optlen); 243 int (*getsockopt)(struct sock *sk, int level, 244 int optname, char __user *optval, 245 int __user *optlen); 246 int (*hash)(struct sock *sk); 247 void (*unhash)(struct sock *sk); 248 }; 249 250 struct tls_offload_context_rx { 251 /* sw must be the first member of tls_offload_context_rx */ 252 struct tls_sw_context_rx sw; 253 atomic64_t resync_req; 254 u8 driver_state[]; 255 /* The TLS layer reserves room for driver specific state 256 * Currently the belief is that there is not enough 257 * driver specific state to justify another layer of indirection 258 */ 259 }; 260 261 #define TLS_OFFLOAD_CONTEXT_SIZE_RX \ 262 (ALIGN(sizeof(struct tls_offload_context_rx), sizeof(void *)) + \ 263 TLS_DRIVER_STATE_SIZE) 264 265 int wait_on_pending_writer(struct sock *sk, long *timeo); 266 int tls_sk_query(struct sock *sk, int optname, char __user *optval, 267 int __user *optlen); 268 int tls_sk_attach(struct sock *sk, int optname, char __user *optval, 269 unsigned int optlen); 270 271 int tls_set_sw_offload(struct sock *sk, struct tls_context *ctx, int tx); 272 int tls_sw_sendmsg(struct sock *sk, struct msghdr *msg, size_t size); 273 int tls_sw_sendpage(struct sock *sk, struct page *page, 274 int offset, size_t size, int flags); 275 void tls_sw_close(struct sock *sk, long timeout); 276 void tls_sw_free_resources_tx(struct sock *sk); 277 void tls_sw_free_resources_rx(struct sock *sk); 278 void tls_sw_release_resources_rx(struct sock *sk); 279 int tls_sw_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, 280 int nonblock, int flags, int *addr_len); 281 bool tls_sw_stream_read(const struct sock *sk); 282 ssize_t tls_sw_splice_read(struct socket *sock, loff_t *ppos, 283 struct pipe_inode_info *pipe, 284 size_t len, unsigned int flags); 285 286 int tls_set_device_offload(struct sock *sk, struct tls_context *ctx); 287 int tls_device_sendmsg(struct sock *sk, struct msghdr *msg, size_t size); 288 int tls_device_sendpage(struct sock *sk, struct page *page, 289 int offset, size_t size, int flags); 290 void tls_device_sk_destruct(struct sock *sk); 291 void tls_device_init(void); 292 void tls_device_cleanup(void); 293 int tls_tx_records(struct sock *sk, int flags); 294 295 struct tls_record_info *tls_get_record(struct tls_offload_context_tx *context, 296 u32 seq, u64 *p_record_sn); 297 298 static inline bool tls_record_is_start_marker(struct tls_record_info *rec) 299 { 300 return rec->len == 0; 301 } 302 303 static inline u32 tls_record_start_seq(struct tls_record_info *rec) 304 { 305 return rec->end_seq - rec->len; 306 } 307 308 void tls_sk_destruct(struct sock *sk, struct tls_context *ctx); 309 int tls_push_sg(struct sock *sk, struct tls_context *ctx, 310 struct scatterlist *sg, u16 first_offset, 311 int flags); 312 int tls_push_partial_record(struct sock *sk, struct tls_context *ctx, 313 int flags); 314 315 int tls_push_pending_closed_record(struct sock *sk, struct tls_context *ctx, 316 int flags, long *timeo); 317 318 static inline bool tls_is_pending_closed_record(struct tls_context *ctx) 319 { 320 return test_bit(TLS_PENDING_CLOSED_RECORD, &ctx->flags); 321 } 322 323 static inline int tls_complete_pending_work(struct sock *sk, 324 struct tls_context *ctx, 325 int flags, long *timeo) 326 { 327 int rc = 0; 328 329 if (unlikely(sk->sk_write_pending)) 330 rc = wait_on_pending_writer(sk, timeo); 331 332 if (!rc && tls_is_pending_closed_record(ctx)) 333 rc = tls_push_pending_closed_record(sk, ctx, flags, timeo); 334 335 return rc; 336 } 337 338 static inline bool tls_is_partially_sent_record(struct tls_context *ctx) 339 { 340 return !!ctx->partially_sent_record; 341 } 342 343 static inline bool tls_is_pending_open_record(struct tls_context *tls_ctx) 344 { 345 return tls_ctx->pending_open_record_frags; 346 } 347 348 static inline bool is_tx_ready(struct tls_sw_context_tx *ctx) 349 { 350 struct tls_rec *rec; 351 352 rec = list_first_entry(&ctx->tx_list, struct tls_rec, list); 353 if (!rec) 354 return false; 355 356 return READ_ONCE(rec->tx_ready); 357 } 358 359 struct sk_buff * 360 tls_validate_xmit_skb(struct sock *sk, struct net_device *dev, 361 struct sk_buff *skb); 362 363 static inline bool tls_is_sk_tx_device_offloaded(struct sock *sk) 364 { 365 #ifdef CONFIG_SOCK_VALIDATE_XMIT 366 return sk_fullsock(sk) & 367 (smp_load_acquire(&sk->sk_validate_xmit_skb) == 368 &tls_validate_xmit_skb); 369 #else 370 return false; 371 #endif 372 } 373 374 static inline void tls_err_abort(struct sock *sk, int err) 375 { 376 sk->sk_err = err; 377 sk->sk_error_report(sk); 378 } 379 380 static inline bool tls_bigint_increment(unsigned char *seq, int len) 381 { 382 int i; 383 384 for (i = len - 1; i >= 0; i--) { 385 ++seq[i]; 386 if (seq[i] != 0) 387 break; 388 } 389 390 return (i == -1); 391 } 392 393 static inline void tls_advance_record_sn(struct sock *sk, 394 struct cipher_context *ctx) 395 { 396 if (tls_bigint_increment(ctx->rec_seq, ctx->rec_seq_size)) 397 tls_err_abort(sk, EBADMSG); 398 tls_bigint_increment(ctx->iv + TLS_CIPHER_AES_GCM_128_SALT_SIZE, 399 ctx->iv_size); 400 } 401 402 static inline void tls_fill_prepend(struct tls_context *ctx, 403 char *buf, 404 size_t plaintext_len, 405 unsigned char record_type) 406 { 407 size_t pkt_len, iv_size = ctx->tx.iv_size; 408 409 pkt_len = plaintext_len + iv_size + ctx->tx.tag_size; 410 411 /* we cover nonce explicit here as well, so buf should be of 412 * size KTLS_DTLS_HEADER_SIZE + KTLS_DTLS_NONCE_EXPLICIT_SIZE 413 */ 414 buf[0] = record_type; 415 buf[1] = TLS_VERSION_MINOR(ctx->crypto_send.info.version); 416 buf[2] = TLS_VERSION_MAJOR(ctx->crypto_send.info.version); 417 /* we can use IV for nonce explicit according to spec */ 418 buf[3] = pkt_len >> 8; 419 buf[4] = pkt_len & 0xFF; 420 memcpy(buf + TLS_NONCE_OFFSET, 421 ctx->tx.iv + TLS_CIPHER_AES_GCM_128_SALT_SIZE, iv_size); 422 } 423 424 static inline void tls_make_aad(char *buf, 425 size_t size, 426 char *record_sequence, 427 int record_sequence_size, 428 unsigned char record_type) 429 { 430 memcpy(buf, record_sequence, record_sequence_size); 431 432 buf[8] = record_type; 433 buf[9] = TLS_1_2_VERSION_MAJOR; 434 buf[10] = TLS_1_2_VERSION_MINOR; 435 buf[11] = size >> 8; 436 buf[12] = size & 0xFF; 437 } 438 439 static inline struct tls_context *tls_get_ctx(const struct sock *sk) 440 { 441 struct inet_connection_sock *icsk = inet_csk(sk); 442 443 return icsk->icsk_ulp_data; 444 } 445 446 static inline struct tls_sw_context_rx *tls_sw_ctx_rx( 447 const struct tls_context *tls_ctx) 448 { 449 return (struct tls_sw_context_rx *)tls_ctx->priv_ctx_rx; 450 } 451 452 static inline struct tls_sw_context_tx *tls_sw_ctx_tx( 453 const struct tls_context *tls_ctx) 454 { 455 return (struct tls_sw_context_tx *)tls_ctx->priv_ctx_tx; 456 } 457 458 static inline struct tls_offload_context_tx * 459 tls_offload_ctx_tx(const struct tls_context *tls_ctx) 460 { 461 return (struct tls_offload_context_tx *)tls_ctx->priv_ctx_tx; 462 } 463 464 static inline bool tls_sw_has_ctx_tx(const struct sock *sk) 465 { 466 struct tls_context *ctx = tls_get_ctx(sk); 467 468 if (!ctx) 469 return false; 470 return !!tls_sw_ctx_tx(ctx); 471 } 472 473 static inline struct tls_offload_context_rx * 474 tls_offload_ctx_rx(const struct tls_context *tls_ctx) 475 { 476 return (struct tls_offload_context_rx *)tls_ctx->priv_ctx_rx; 477 } 478 479 /* The TLS context is valid until sk_destruct is called */ 480 static inline void tls_offload_rx_resync_request(struct sock *sk, __be32 seq) 481 { 482 struct tls_context *tls_ctx = tls_get_ctx(sk); 483 struct tls_offload_context_rx *rx_ctx = tls_offload_ctx_rx(tls_ctx); 484 485 atomic64_set(&rx_ctx->resync_req, ((((uint64_t)seq) << 32) | 1)); 486 } 487 488 489 int tls_proccess_cmsg(struct sock *sk, struct msghdr *msg, 490 unsigned char *record_type); 491 void tls_register_device(struct tls_device *device); 492 void tls_unregister_device(struct tls_device *device); 493 int tls_device_decrypted(struct sock *sk, struct sk_buff *skb); 494 int decrypt_skb(struct sock *sk, struct sk_buff *skb, 495 struct scatterlist *sgout); 496 497 struct sk_buff *tls_validate_xmit_skb(struct sock *sk, 498 struct net_device *dev, 499 struct sk_buff *skb); 500 501 int tls_sw_fallback_init(struct sock *sk, 502 struct tls_offload_context_tx *offload_ctx, 503 struct tls_crypto_info *crypto_info); 504 505 int tls_set_device_offload_rx(struct sock *sk, struct tls_context *ctx); 506 507 void tls_device_offload_cleanup_rx(struct sock *sk); 508 void handle_device_resync(struct sock *sk, u32 seq, u64 rcd_sn); 509 510 #endif /* _TLS_OFFLOAD_H */ 511