summaryrefslogtreecommitdiff
path: root/include/net/tls.h
blob: 6056ce5a2aa5fb666b395f8f21f7b501f2ef2dc3 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
/*
 * Copyright (c) 2016-2017, Mellanox Technologies. All rights reserved.
 * Copyright (c) 2016-2017, Dave Watson <davejwatson@fb.com>. All rights reserved.
 *
 * This software is available to you under a choice of one of two
 * licenses.  You may choose to be licensed under the terms of the GNU
 * General Public License (GPL) Version 2, available from the file
 * COPYING in the main directory of this source tree, or the
 * OpenIB.org BSD license below:
 *
 *     Redistribution and use in source and binary forms, with or
 *     without modification, are permitted provided that the following
 *     conditions are met:
 *
 *      - Redistributions of source code must retain the above
 *        copyright notice, this list of conditions and the following
 *        disclaimer.
 *
 *      - Redistributions in binary form must reproduce the above
 *        copyright notice, this list of conditions and the following
 *        disclaimer in the documentation and/or other materials
 *        provided with the distribution.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */

#ifndef _TLS_OFFLOAD_H
#define _TLS_OFFLOAD_H

#include <linux/types.h>
#include <asm/byteorder.h>
#include <linux/crypto.h>
#include <linux/socket.h>
#include <linux/tcp.h>
#include <linux/mutex.h>
#include <linux/netdevice.h>
#include <linux/rcupdate.h>

#include <net/net_namespace.h>
#include <net/tcp.h>
#include <net/strparser.h>
#include <crypto/aead.h>
#include <uapi/linux/tls.h>

struct tls_rec;

struct tls_cipher_size_desc {
	unsigned int iv;
	unsigned int key;
	unsigned int salt;
	unsigned int tag;
	unsigned int rec_seq;
};

extern const struct tls_cipher_size_desc tls_cipher_size_desc[];

/* Maximum data size carried in a TLS record */
#define TLS_MAX_PAYLOAD_SIZE		((size_t)1 << 14)

#define TLS_HEADER_SIZE			5
#define TLS_NONCE_OFFSET		TLS_HEADER_SIZE

#define TLS_CRYPTO_INFO_READY(info)	((info)->cipher_type)

#define TLS_RECORD_TYPE_ALERT		0x15
#define TLS_RECORD_TYPE_HANDSHAKE	0x16
#define TLS_RECORD_TYPE_DATA		0x17

#define TLS_AAD_SPACE_SIZE		13

#define MAX_IV_SIZE			16
#define TLS_TAG_SIZE			16
#define TLS_MAX_REC_SEQ_SIZE		8
#define TLS_MAX_AAD_SIZE		TLS_AAD_SPACE_SIZE

/* For CCM mode, the full 16-bytes of IV is made of '4' fields of given sizes.
 *
 * IV[16] = b0[1] || implicit nonce[4] || explicit nonce[8] || length[3]
 *
 * The field 'length' is encoded in field 'b0' as '(length width - 1)'.
 * Hence b0 contains (3 - 1) = 2.
 */
#define TLS_AES_CCM_IV_B0_BYTE		2
#define TLS_SM4_CCM_IV_B0_BYTE		2

enum {
	TLS_BASE,
	TLS_SW,
	TLS_HW,
	TLS_HW_RECORD,
	TLS_NUM_CONFIG,
};

struct tx_work {
	struct delayed_work work;
	struct sock *sk;
};

struct tls_sw_context_tx {
	struct crypto_aead *aead_send;
	struct crypto_wait async_wait;
	struct tx_work tx_work;
	struct tls_rec *open_rec;
	struct list_head tx_list;
	atomic_t encrypt_pending;
	/* protect crypto_wait with encrypt_pending */
	spinlock_t encrypt_compl_lock;
	int async_notify;
	u8 async_capable:1;

#define BIT_TX_SCHEDULED	0
#define BIT_TX_CLOSING		1
	unsigned long tx_bitmask;
};

struct tls_strparser {
	struct sock *sk;

	u32 mark : 8;
	u32 stopped : 1;
	u32 copy_mode : 1;
	u32 msg_ready : 1;

	struct strp_msg stm;

	struct sk_buff *anchor;
	struct work_struct work;
};

struct tls_sw_context_rx {
	struct crypto_aead *aead_recv;
	struct crypto_wait async_wait;
	struct sk_buff_head rx_list;	/* list of decrypted 'data' records */
	void (*saved_data_ready)(struct sock *sk);

	u8 reader_present;
	u8 async_capable:1;
	u8 zc_capable:1;
	u8 reader_contended:1;

	struct tls_strparser strp;

	atomic_t decrypt_pending;
	/* protect crypto_wait with decrypt_pending*/
	spinlock_t decrypt_compl_lock;
	struct sk_buff_head async_hold;
	struct wait_queue_head wq;
};

struct tls_record_info {
	struct list_head list;
	u32 end_seq;
	int len;
	int num_frags;
	skb_frag_t frags[MAX_SKB_FRAGS];
};

struct tls_offload_context_tx {
	struct crypto_aead *aead_send;
	spinlock_t lock;	/* protects records list */
	struct list_head records_list;
	struct tls_record_info *open_record;
	struct tls_record_info *retransmit_hint;
	u64 hint_record_sn;
	u64 unacked_record_sn;

	struct scatterlist sg_tx_data[MAX_SKB_FRAGS];
	void (*sk_destruct)(struct sock *sk);
	struct work_struct destruct_work;
	struct tls_context *ctx;
	u8 driver_state[] __aligned(8);
	/* The TLS layer reserves room for driver specific state
	 * Currently the belief is that there is not enough
	 * driver specific state to justify another layer of indirection
	 */
#define TLS_DRIVER_STATE_SIZE_TX	16
};

#define TLS_OFFLOAD_CONTEXT_SIZE_TX                                            \
	(sizeof(struct tls_offload_context_tx) + TLS_DRIVER_STATE_SIZE_TX)

enum tls_context_flags {
	/* tls_device_down was called after the netdev went down, device state
	 * was released, and kTLS works in software, even though rx_conf is
	 * still TLS_HW (needed for transition).
	 */
	TLS_RX_DEV_DEGRADED = 0,
	/* Unlike RX where resync is driven entirely by the core in TX only
	 * the driver knows when things went out of sync, so we need the flag
	 * to be atomic.
	 */
	TLS_TX_SYNC_SCHED = 1,
	/* tls_dev_del was called for the RX side, device state was released,
	 * but tls_ctx->netdev might still be kept, because TX-side driver
	 * resources might not be released yet. Used to prevent the second
	 * tls_dev_del call in tls_device_down if it happens simultaneously.
	 */
	TLS_RX_DEV_CLOSED = 2,
};

struct cipher_context {
	char *iv;
	char *rec_seq;
};

union tls_crypto_context {
	struct tls_crypto_info info;
	union {
		struct tls12_crypto_info_aes_gcm_128 aes_gcm_128;
		struct tls12_crypto_info_aes_gcm_256 aes_gcm_256;
		struct tls12_crypto_info_chacha20_poly1305 chacha20_poly1305;
		struct tls12_crypto_info_sm4_gcm sm4_gcm;
		struct tls12_crypto_info_sm4_ccm sm4_ccm;
	};
};

struct tls_prot_info {
	u16 version;
	u16 cipher_type;
	u16 prepend_size;
	u16 tag_size;
	u16 overhead_size;
	u16 iv_size;
	u16 salt_size;
	u16 rec_seq_size;
	u16 aad_size;
	u16 tail_size;
};

struct tls_context {
	/* read-only cache line */
	struct tls_prot_info prot_info;

	u8 tx_conf:3;
	u8 rx_conf:3;
	u8 zerocopy_sendfile:1;
	u8 rx_no_pad:1;

	int (*push_pending_record)(struct sock *sk, int flags);
	void (*sk_write_space)(struct sock *sk);

	void *priv_ctx_tx;
	void *priv_ctx_rx;

	struct net_device __rcu *netdev;

	/* rw cache line */
	struct cipher_context tx;
	struct cipher_context rx;

	struct scatterlist *partially_sent_record;
	u16 partially_sent_offset;

	bool in_tcp_sendpages;
	bool pending_open_record_frags;

	struct mutex tx_lock; /* protects partially_sent_* fields and
			       * per-type TX fields
			       */
	unsigned long flags;

	/* cache cold stuff */
	struct proto *sk_proto;
	struct sock *sk;

	void (*sk_destruct)(struct sock *sk);

	union tls_crypto_context crypto_send;
	union tls_crypto_context crypto_recv;

	struct list_head list;
	refcount_t refcount;
	struct rcu_head rcu;
};

enum tls_offload_ctx_dir {
	TLS_OFFLOAD_CTX_DIR_RX,
	TLS_OFFLOAD_CTX_DIR_TX,
};

struct tlsdev_ops {
	int (*tls_dev_add)(struct net_device *netdev, struct sock *sk,
			   enum tls_offload_ctx_dir direction,
			   struct tls_crypto_info *crypto_info,
			   u32 start_offload_tcp_sn);
	void (*tls_dev_del)(struct net_device *netdev,
			    struct tls_context *ctx,
			    enum tls_offload_ctx_dir direction);
	int (*tls_dev_resync)(struct net_device *netdev,
			      struct sock *sk, u32 seq, u8 *rcd_sn,
			      enum tls_offload_ctx_dir direction);
};

enum tls_offload_sync_type {
	TLS_OFFLOAD_SYNC_TYPE_DRIVER_REQ = 0,
	TLS_OFFLOAD_SYNC_TYPE_CORE_NEXT_HINT = 1,
	TLS_OFFLOAD_SYNC_TYPE_DRIVER_REQ_ASYNC = 2,
};

#define TLS_DEVICE_RESYNC_NH_START_IVAL		2
#define TLS_DEVICE_RESYNC_NH_MAX_IVAL		128

#define TLS_DEVICE_RESYNC_ASYNC_LOGMAX		13
struct tls_offload_resync_async {
	atomic64_t req;
	u16 loglen;
	u16 rcd_delta;
	u32 log[TLS_DEVICE_RESYNC_ASYNC_LOGMAX];
};

struct tls_offload_context_rx {
	/* sw must be the first member of tls_offload_context_rx */
	struct tls_sw_context_rx sw;
	enum tls_offload_sync_type resync_type;
	/* this member is set regardless of resync_type, to avoid branches */
	u8 resync_nh_reset:1;
	/* CORE_NEXT_HINT-only member, but use the hole here */
	u8 resync_nh_do_now:1;
	union {
		/* TLS_OFFLOAD_SYNC_TYPE_DRIVER_REQ */
		struct {
			atomic64_t resync_req;
		};
		/* TLS_OFFLOAD_SYNC_TYPE_CORE_NEXT_HINT */
		struct {
			u32 decrypted_failed;
			u32 decrypted_tgt;
		} resync_nh;
		/* TLS_OFFLOAD_SYNC_TYPE_DRIVER_REQ_ASYNC */
		struct {
			struct tls_offload_resync_async *resync_async;
		};
	};
	u8 driver_state[] __aligned(8);
	/* The TLS layer reserves room for driver specific state
	 * Currently the belief is that there is not enough
	 * driver specific state to justify another layer of indirection
	 */
#define TLS_DRIVER_STATE_SIZE_RX	8
};

#define TLS_OFFLOAD_CONTEXT_SIZE_RX					\
	(sizeof(struct tls_offload_context_rx) + TLS_DRIVER_STATE_SIZE_RX)

struct tls_record_info *tls_get_record(struct tls_offload_context_tx *context,
				       u32 seq, u64 *p_record_sn);

static inline bool tls_record_is_start_marker(struct tls_record_info *rec)
{
	return rec->len == 0;
}

static inline u32 tls_record_start_seq(struct tls_record_info *rec)
{
	return rec->end_seq - rec->len;
}

struct sk_buff *
tls_validate_xmit_skb(struct sock *sk, struct net_device *dev,
		      struct sk_buff *skb);
struct sk_buff *
tls_validate_xmit_skb_sw(struct sock *sk, struct net_device *dev,
			 struct sk_buff *skb);

static inline bool tls_is_sk_tx_device_offloaded(struct sock *sk)
{
#ifdef CONFIG_SOCK_VALIDATE_XMIT
	return sk_fullsock(sk) &&
	       (smp_load_acquire(&sk->sk_validate_xmit_skb) ==
	       &tls_validate_xmit_skb);
#else
	return false;
#endif
}

static inline struct tls_context *tls_get_ctx(const struct sock *sk)
{
	struct inet_connection_sock *icsk = inet_csk(sk);

	/* Use RCU on icsk_ulp_data only for sock diag code,
	 * TLS data path doesn't need rcu_dereference().
	 */
	return (__force void *)icsk->icsk_ulp_data;
}

static inline struct tls_sw_context_rx *tls_sw_ctx_rx(
		const struct tls_context *tls_ctx)
{
	return (struct tls_sw_context_rx *)tls_ctx->priv_ctx_rx;
}

static inline struct tls_sw_context_tx *tls_sw_ctx_tx(
		const struct tls_context *tls_ctx)
{
	return (struct tls_sw_context_tx *)tls_ctx->priv_ctx_tx;
}

static inline struct tls_offload_context_tx *
tls_offload_ctx_tx(const struct tls_context *tls_ctx)
{
	return (struct tls_offload_context_tx *)tls_ctx->priv_ctx_tx;
}

static inline bool tls_sw_has_ctx_tx(const struct sock *sk)
{
	struct tls_context *ctx = tls_get_ctx(sk);

	if (!ctx)
		return false;
	return !!tls_sw_ctx_tx(ctx);
}

static inline bool tls_sw_has_ctx_rx(const struct sock *sk)
{
	struct tls_context *ctx = tls_get_ctx(sk);

	if (!ctx)
		return false;
	return !!tls_sw_ctx_rx(ctx);
}

static inline struct tls_offload_context_rx *
tls_offload_ctx_rx(const struct tls_context *tls_ctx)
{
	return (struct tls_offload_context_rx *)tls_ctx->priv_ctx_rx;
}

static inline void *__tls_driver_ctx(struct tls_context *tls_ctx,
				     enum tls_offload_ctx_dir direction)
{
	if (direction == TLS_OFFLOAD_CTX_DIR_TX)
		return tls_offload_ctx_tx(tls_ctx)->driver_state;
	else
		return tls_offload_ctx_rx(tls_ctx)->driver_state;
}

static inline void *
tls_driver_ctx(const struct sock *sk, enum tls_offload_ctx_dir direction)
{
	return __tls_driver_ctx(tls_get_ctx(sk), direction);
}

#define RESYNC_REQ BIT(0)
#define RESYNC_REQ_ASYNC BIT(1)
/* The TLS context is valid until sk_destruct is called */
static inline void tls_offload_rx_resync_request(struct sock *sk, __be32 seq)
{
	struct tls_context *tls_ctx = tls_get_ctx(sk);
	struct tls_offload_context_rx *rx_ctx = tls_offload_ctx_rx(tls_ctx);

	atomic64_set(&rx_ctx->resync_req, ((u64)ntohl(seq) << 32) | RESYNC_REQ);
}

/* Log all TLS record header TCP sequences in [seq, seq+len] */
static inline void
tls_offload_rx_resync_async_request_start(struct sock *sk, __be32 seq, u16 len)
{
	struct tls_context *tls_ctx = tls_get_ctx(sk);
	struct tls_offload_context_rx *rx_ctx = tls_offload_ctx_rx(tls_ctx);

	atomic64_set(&rx_ctx->resync_async->req, ((u64)ntohl(seq) << 32) |
		     ((u64)len << 16) | RESYNC_REQ | RESYNC_REQ_ASYNC);
	rx_ctx->resync_async->loglen = 0;
	rx_ctx->resync_async->rcd_delta = 0;
}

static inline void
tls_offload_rx_resync_async_request_end(struct sock *sk, __be32 seq)
{
	struct tls_context *tls_ctx = tls_get_ctx(sk);
	struct tls_offload_context_rx *rx_ctx = tls_offload_ctx_rx(tls_ctx);

	atomic64_set(&rx_ctx->resync_async->req,
		     ((u64)ntohl(seq) << 32) | RESYNC_REQ);
}

static inline void
tls_offload_rx_resync_set_type(struct sock *sk, enum tls_offload_sync_type type)
{
	struct tls_context *tls_ctx = tls_get_ctx(sk);

	tls_offload_ctx_rx(tls_ctx)->resync_type = type;
}

/* Driver's seq tracking has to be disabled until resync succeeded */
static inline bool tls_offload_tx_resync_pending(struct sock *sk)
{
	struct tls_context *tls_ctx = tls_get_ctx(sk);
	bool ret;

	ret = test_bit(TLS_TX_SYNC_SCHED, &tls_ctx->flags);
	smp_mb__after_atomic();
	return ret;
}

struct sk_buff *tls_encrypt_skb(struct sk_buff *skb);

#ifdef CONFIG_TLS_DEVICE
void tls_device_sk_destruct(struct sock *sk);
void tls_offload_tx_resync_request(struct sock *sk, u32 got_seq, u32 exp_seq);

static inline bool tls_is_sk_rx_device_offloaded(struct sock *sk)
{
	if (!sk_fullsock(sk) ||
	    smp_load_acquire(&sk->sk_destruct) != tls_device_sk_destruct)
		return false;
	return tls_get_ctx(sk)->rx_conf == TLS_HW;
}
#endif
#endif /* _TLS_OFFLOAD_H */