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 <net/tcp.h> 43 #include <net/strparser.h> 44 #include <crypto/aead.h> 45 #include <uapi/linux/tls.h> 46 47 48 /* Maximum data size carried in a TLS record */ 49 #define TLS_MAX_PAYLOAD_SIZE ((size_t)1 << 14) 50 51 #define TLS_HEADER_SIZE 5 52 #define TLS_NONCE_OFFSET TLS_HEADER_SIZE 53 54 #define TLS_CRYPTO_INFO_READY(info) ((info)->cipher_type) 55 56 #define TLS_RECORD_TYPE_DATA 0x17 57 58 #define TLS_AAD_SPACE_SIZE 13 59 #define TLS_DEVICE_NAME_MAX 32 60 61 /* 62 * This structure defines the routines for Inline TLS driver. 63 * The following routines are optional and filled with a 64 * null pointer if not defined. 65 * 66 * @name: Its the name of registered Inline tls device 67 * @dev_list: Inline tls device list 68 * int (*feature)(struct tls_device *device); 69 * Called to return Inline TLS driver capability 70 * 71 * int (*hash)(struct tls_device *device, struct sock *sk); 72 * This function sets Inline driver for listen and program 73 * device specific functioanlity as required 74 * 75 * void (*unhash)(struct tls_device *device, struct sock *sk); 76 * This function cleans listen state set by Inline TLS driver 77 */ 78 struct tls_device { 79 char name[TLS_DEVICE_NAME_MAX]; 80 struct list_head dev_list; 81 int (*feature)(struct tls_device *device); 82 int (*hash)(struct tls_device *device, struct sock *sk); 83 void (*unhash)(struct tls_device *device, struct sock *sk); 84 }; 85 86 enum { 87 TLS_BASE, 88 TLS_SW, 89 #ifdef CONFIG_TLS_DEVICE 90 TLS_HW, 91 #endif 92 TLS_HW_RECORD, 93 TLS_NUM_CONFIG, 94 }; 95 96 /* TLS records are maintained in 'struct tls_rec'. It stores the memory pages 97 * allocated or mapped for each TLS record. After encryption, the records are 98 * stores in a linked list. 99 */ 100 struct tls_rec { 101 struct list_head list; 102 int tx_ready; 103 int tx_flags; 104 struct scatterlist sg_plaintext_data[MAX_SKB_FRAGS]; 105 struct scatterlist sg_encrypted_data[MAX_SKB_FRAGS]; 106 107 /* AAD | sg_plaintext_data | sg_tag */ 108 struct scatterlist sg_aead_in[2]; 109 /* AAD | sg_encrypted_data (data contain overhead for hdr&iv&tag) */ 110 struct scatterlist sg_aead_out[2]; 111 112 unsigned int sg_plaintext_size; 113 unsigned int sg_encrypted_size; 114 int sg_plaintext_num_elem; 115 int sg_encrypted_num_elem; 116 117 char aad_space[TLS_AAD_SPACE_SIZE]; 118 struct aead_request aead_req; 119 u8 aead_req_ctx[]; 120 }; 121 122 struct tx_work { 123 struct delayed_work work; 124 struct sock *sk; 125 }; 126 127 struct tls_sw_context_tx { 128 struct crypto_aead *aead_send; 129 struct crypto_wait async_wait; 130 struct tx_work tx_work; 131 struct tls_rec *open_rec; 132 struct list_head tx_list; 133 atomic_t encrypt_pending; 134 int async_notify; 135 136 #define BIT_TX_SCHEDULED 0 137 unsigned long tx_bitmask; 138 }; 139 140 struct tls_sw_context_rx { 141 struct crypto_aead *aead_recv; 142 struct crypto_wait async_wait; 143 144 struct strparser strp; 145 void (*saved_data_ready)(struct sock *sk); 146 unsigned int (*sk_poll)(struct file *file, struct socket *sock, 147 struct poll_table_struct *wait); 148 struct sk_buff *recv_pkt; 149 u8 control; 150 bool decrypted; 151 atomic_t decrypt_pending; 152 bool async_notify; 153 }; 154 155 struct tls_record_info { 156 struct list_head list; 157 u32 end_seq; 158 int len; 159 int num_frags; 160 skb_frag_t frags[MAX_SKB_FRAGS]; 161 }; 162 163 struct tls_offload_context_tx { 164 struct crypto_aead *aead_send; 165 spinlock_t lock; /* protects records list */ 166 struct list_head records_list; 167 struct tls_record_info *open_record; 168 struct tls_record_info *retransmit_hint; 169 u64 hint_record_sn; 170 u64 unacked_record_sn; 171 172 struct scatterlist sg_tx_data[MAX_SKB_FRAGS]; 173 void (*sk_destruct)(struct sock *sk); 174 u8 driver_state[]; 175 /* The TLS layer reserves room for driver specific state 176 * Currently the belief is that there is not enough 177 * driver specific state to justify another layer of indirection 178 */ 179 #define TLS_DRIVER_STATE_SIZE (max_t(size_t, 8, sizeof(void *))) 180 }; 181 182 #define TLS_OFFLOAD_CONTEXT_SIZE_TX \ 183 (ALIGN(sizeof(struct tls_offload_context_tx), sizeof(void *)) + \ 184 TLS_DRIVER_STATE_SIZE) 185 186 enum { 187 TLS_PENDING_CLOSED_RECORD 188 }; 189 190 struct cipher_context { 191 u16 prepend_size; 192 u16 tag_size; 193 u16 overhead_size; 194 u16 iv_size; 195 char *iv; 196 u16 rec_seq_size; 197 char *rec_seq; 198 }; 199 200 union tls_crypto_context { 201 struct tls_crypto_info info; 202 struct tls12_crypto_info_aes_gcm_128 aes_gcm_128; 203 }; 204 205 struct tls_context { 206 union tls_crypto_context crypto_send; 207 union tls_crypto_context crypto_recv; 208 209 struct list_head list; 210 struct net_device *netdev; 211 refcount_t refcount; 212 213 void *priv_ctx_tx; 214 void *priv_ctx_rx; 215 216 u8 tx_conf:3; 217 u8 rx_conf:3; 218 219 struct cipher_context tx; 220 struct cipher_context rx; 221 222 struct scatterlist *partially_sent_record; 223 u16 partially_sent_offset; 224 225 unsigned long flags; 226 bool in_tcp_sendpages; 227 228 u16 pending_open_record_frags; 229 int (*push_pending_record)(struct sock *sk, int flags); 230 231 void (*sk_write_space)(struct sock *sk); 232 void (*sk_destruct)(struct sock *sk); 233 void (*sk_proto_close)(struct sock *sk, long timeout); 234 235 int (*setsockopt)(struct sock *sk, int level, 236 int optname, char __user *optval, 237 unsigned int optlen); 238 int (*getsockopt)(struct sock *sk, int level, 239 int optname, char __user *optval, 240 int __user *optlen); 241 int (*hash)(struct sock *sk); 242 void (*unhash)(struct sock *sk); 243 }; 244 245 struct tls_offload_context_rx { 246 /* sw must be the first member of tls_offload_context_rx */ 247 struct tls_sw_context_rx sw; 248 atomic64_t resync_req; 249 u8 driver_state[]; 250 /* The TLS layer reserves room for driver specific state 251 * Currently the belief is that there is not enough 252 * driver specific state to justify another layer of indirection 253 */ 254 }; 255 256 #define TLS_OFFLOAD_CONTEXT_SIZE_RX \ 257 (ALIGN(sizeof(struct tls_offload_context_rx), sizeof(void *)) + \ 258 TLS_DRIVER_STATE_SIZE) 259 260 int wait_on_pending_writer(struct sock *sk, long *timeo); 261 int tls_sk_query(struct sock *sk, int optname, char __user *optval, 262 int __user *optlen); 263 int tls_sk_attach(struct sock *sk, int optname, char __user *optval, 264 unsigned int optlen); 265 266 int tls_set_sw_offload(struct sock *sk, struct tls_context *ctx, int tx); 267 int tls_sw_sendmsg(struct sock *sk, struct msghdr *msg, size_t size); 268 int tls_sw_sendpage(struct sock *sk, struct page *page, 269 int offset, size_t size, int flags); 270 void tls_sw_close(struct sock *sk, long timeout); 271 void tls_sw_free_resources_tx(struct sock *sk); 272 void tls_sw_free_resources_rx(struct sock *sk); 273 void tls_sw_release_resources_rx(struct sock *sk); 274 int tls_sw_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, 275 int nonblock, int flags, int *addr_len); 276 unsigned int tls_sw_poll(struct file *file, struct socket *sock, 277 struct poll_table_struct *wait); 278 ssize_t tls_sw_splice_read(struct socket *sock, loff_t *ppos, 279 struct pipe_inode_info *pipe, 280 size_t len, unsigned int flags); 281 282 int tls_set_device_offload(struct sock *sk, struct tls_context *ctx); 283 int tls_device_sendmsg(struct sock *sk, struct msghdr *msg, size_t size); 284 int tls_device_sendpage(struct sock *sk, struct page *page, 285 int offset, size_t size, int flags); 286 void tls_device_sk_destruct(struct sock *sk); 287 void tls_device_init(void); 288 void tls_device_cleanup(void); 289 int tls_tx_records(struct sock *sk, int flags); 290 291 struct tls_record_info *tls_get_record(struct tls_offload_context_tx *context, 292 u32 seq, u64 *p_record_sn); 293 294 static inline bool tls_record_is_start_marker(struct tls_record_info *rec) 295 { 296 return rec->len == 0; 297 } 298 299 static inline u32 tls_record_start_seq(struct tls_record_info *rec) 300 { 301 return rec->end_seq - rec->len; 302 } 303 304 void tls_sk_destruct(struct sock *sk, struct tls_context *ctx); 305 int tls_push_sg(struct sock *sk, struct tls_context *ctx, 306 struct scatterlist *sg, u16 first_offset, 307 int flags); 308 int tls_push_partial_record(struct sock *sk, struct tls_context *ctx, 309 int flags); 310 311 int tls_push_pending_closed_record(struct sock *sk, struct tls_context *ctx, 312 int flags, long *timeo); 313 314 static inline bool tls_is_pending_closed_record(struct tls_context *ctx) 315 { 316 return test_bit(TLS_PENDING_CLOSED_RECORD, &ctx->flags); 317 } 318 319 static inline int tls_complete_pending_work(struct sock *sk, 320 struct tls_context *ctx, 321 int flags, long *timeo) 322 { 323 int rc = 0; 324 325 if (unlikely(sk->sk_write_pending)) 326 rc = wait_on_pending_writer(sk, timeo); 327 328 if (!rc && tls_is_pending_closed_record(ctx)) 329 rc = tls_push_pending_closed_record(sk, ctx, flags, timeo); 330 331 return rc; 332 } 333 334 static inline bool tls_is_partially_sent_record(struct tls_context *ctx) 335 { 336 return !!ctx->partially_sent_record; 337 } 338 339 static inline bool tls_is_pending_open_record(struct tls_context *tls_ctx) 340 { 341 return tls_ctx->pending_open_record_frags; 342 } 343 344 static inline bool is_tx_ready(struct tls_sw_context_tx *ctx) 345 { 346 struct tls_rec *rec; 347 348 rec = list_first_entry(&ctx->tx_list, struct tls_rec, list); 349 if (!rec) 350 return false; 351 352 return READ_ONCE(rec->tx_ready); 353 } 354 355 struct sk_buff * 356 tls_validate_xmit_skb(struct sock *sk, struct net_device *dev, 357 struct sk_buff *skb); 358 359 static inline bool tls_is_sk_tx_device_offloaded(struct sock *sk) 360 { 361 #ifdef CONFIG_SOCK_VALIDATE_XMIT 362 return sk_fullsock(sk) & 363 (smp_load_acquire(&sk->sk_validate_xmit_skb) == 364 &tls_validate_xmit_skb); 365 #else 366 return false; 367 #endif 368 } 369 370 static inline void tls_err_abort(struct sock *sk, int err) 371 { 372 sk->sk_err = err; 373 sk->sk_error_report(sk); 374 } 375 376 static inline bool tls_bigint_increment(unsigned char *seq, int len) 377 { 378 int i; 379 380 for (i = len - 1; i >= 0; i--) { 381 ++seq[i]; 382 if (seq[i] != 0) 383 break; 384 } 385 386 return (i == -1); 387 } 388 389 static inline void tls_advance_record_sn(struct sock *sk, 390 struct cipher_context *ctx) 391 { 392 if (tls_bigint_increment(ctx->rec_seq, ctx->rec_seq_size)) 393 tls_err_abort(sk, EBADMSG); 394 tls_bigint_increment(ctx->iv + TLS_CIPHER_AES_GCM_128_SALT_SIZE, 395 ctx->iv_size); 396 } 397 398 static inline void tls_fill_prepend(struct tls_context *ctx, 399 char *buf, 400 size_t plaintext_len, 401 unsigned char record_type) 402 { 403 size_t pkt_len, iv_size = ctx->tx.iv_size; 404 405 pkt_len = plaintext_len + iv_size + ctx->tx.tag_size; 406 407 /* we cover nonce explicit here as well, so buf should be of 408 * size KTLS_DTLS_HEADER_SIZE + KTLS_DTLS_NONCE_EXPLICIT_SIZE 409 */ 410 buf[0] = record_type; 411 buf[1] = TLS_VERSION_MINOR(ctx->crypto_send.info.version); 412 buf[2] = TLS_VERSION_MAJOR(ctx->crypto_send.info.version); 413 /* we can use IV for nonce explicit according to spec */ 414 buf[3] = pkt_len >> 8; 415 buf[4] = pkt_len & 0xFF; 416 memcpy(buf + TLS_NONCE_OFFSET, 417 ctx->tx.iv + TLS_CIPHER_AES_GCM_128_SALT_SIZE, iv_size); 418 } 419 420 static inline void tls_make_aad(char *buf, 421 size_t size, 422 char *record_sequence, 423 int record_sequence_size, 424 unsigned char record_type) 425 { 426 memcpy(buf, record_sequence, record_sequence_size); 427 428 buf[8] = record_type; 429 buf[9] = TLS_1_2_VERSION_MAJOR; 430 buf[10] = TLS_1_2_VERSION_MINOR; 431 buf[11] = size >> 8; 432 buf[12] = size & 0xFF; 433 } 434 435 static inline struct tls_context *tls_get_ctx(const struct sock *sk) 436 { 437 struct inet_connection_sock *icsk = inet_csk(sk); 438 439 return icsk->icsk_ulp_data; 440 } 441 442 static inline struct tls_sw_context_rx *tls_sw_ctx_rx( 443 const struct tls_context *tls_ctx) 444 { 445 return (struct tls_sw_context_rx *)tls_ctx->priv_ctx_rx; 446 } 447 448 static inline struct tls_sw_context_tx *tls_sw_ctx_tx( 449 const struct tls_context *tls_ctx) 450 { 451 return (struct tls_sw_context_tx *)tls_ctx->priv_ctx_tx; 452 } 453 454 static inline struct tls_offload_context_tx * 455 tls_offload_ctx_tx(const struct tls_context *tls_ctx) 456 { 457 return (struct tls_offload_context_tx *)tls_ctx->priv_ctx_tx; 458 } 459 460 static inline struct tls_offload_context_rx * 461 tls_offload_ctx_rx(const struct tls_context *tls_ctx) 462 { 463 return (struct tls_offload_context_rx *)tls_ctx->priv_ctx_rx; 464 } 465 466 /* The TLS context is valid until sk_destruct is called */ 467 static inline void tls_offload_rx_resync_request(struct sock *sk, __be32 seq) 468 { 469 struct tls_context *tls_ctx = tls_get_ctx(sk); 470 struct tls_offload_context_rx *rx_ctx = tls_offload_ctx_rx(tls_ctx); 471 472 atomic64_set(&rx_ctx->resync_req, ((((uint64_t)seq) << 32) | 1)); 473 } 474 475 476 int tls_proccess_cmsg(struct sock *sk, struct msghdr *msg, 477 unsigned char *record_type); 478 void tls_register_device(struct tls_device *device); 479 void tls_unregister_device(struct tls_device *device); 480 int tls_device_decrypted(struct sock *sk, struct sk_buff *skb); 481 int decrypt_skb(struct sock *sk, struct sk_buff *skb, 482 struct scatterlist *sgout); 483 484 struct sk_buff *tls_validate_xmit_skb(struct sock *sk, 485 struct net_device *dev, 486 struct sk_buff *skb); 487 488 int tls_sw_fallback_init(struct sock *sk, 489 struct tls_offload_context_tx *offload_ctx, 490 struct tls_crypto_info *crypto_info); 491 492 int tls_set_device_offload_rx(struct sock *sk, struct tls_context *ctx); 493 494 void tls_device_offload_cleanup_rx(struct sock *sk); 495 void handle_device_resync(struct sock *sk, u32 seq, u64 rcd_sn); 496 497 #endif /* _TLS_OFFLOAD_H */ 498