xref: /openbmc/linux/net/tls/tls_main.c (revision f2f4bf5a)
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 #include <linux/module.h>
35 
36 #include <net/tcp.h>
37 #include <net/inet_common.h>
38 #include <linux/highmem.h>
39 #include <linux/netdevice.h>
40 #include <linux/sched/signal.h>
41 #include <linux/inetdevice.h>
42 
43 #include <net/tls.h>
44 
45 MODULE_AUTHOR("Mellanox Technologies");
46 MODULE_DESCRIPTION("Transport Layer Security Support");
47 MODULE_LICENSE("Dual BSD/GPL");
48 MODULE_ALIAS_TCP_ULP("tls");
49 
50 enum {
51 	TLSV4,
52 	TLSV6,
53 	TLS_NUM_PROTS,
54 };
55 
56 static struct proto *saved_tcpv6_prot;
57 static DEFINE_MUTEX(tcpv6_prot_mutex);
58 static struct proto *saved_tcpv4_prot;
59 static DEFINE_MUTEX(tcpv4_prot_mutex);
60 static LIST_HEAD(device_list);
61 static DEFINE_SPINLOCK(device_spinlock);
62 static struct proto tls_prots[TLS_NUM_PROTS][TLS_NUM_CONFIG][TLS_NUM_CONFIG];
63 static struct proto_ops tls_sw_proto_ops;
64 static void build_protos(struct proto prot[TLS_NUM_CONFIG][TLS_NUM_CONFIG],
65 			 struct proto *base);
66 
67 static void update_sk_prot(struct sock *sk, struct tls_context *ctx)
68 {
69 	int ip_ver = sk->sk_family == AF_INET6 ? TLSV6 : TLSV4;
70 
71 	sk->sk_prot = &tls_prots[ip_ver][ctx->tx_conf][ctx->rx_conf];
72 }
73 
74 int wait_on_pending_writer(struct sock *sk, long *timeo)
75 {
76 	int rc = 0;
77 	DEFINE_WAIT_FUNC(wait, woken_wake_function);
78 
79 	add_wait_queue(sk_sleep(sk), &wait);
80 	while (1) {
81 		if (!*timeo) {
82 			rc = -EAGAIN;
83 			break;
84 		}
85 
86 		if (signal_pending(current)) {
87 			rc = sock_intr_errno(*timeo);
88 			break;
89 		}
90 
91 		if (sk_wait_event(sk, timeo, !sk->sk_write_pending, &wait))
92 			break;
93 	}
94 	remove_wait_queue(sk_sleep(sk), &wait);
95 	return rc;
96 }
97 
98 int tls_push_sg(struct sock *sk,
99 		struct tls_context *ctx,
100 		struct scatterlist *sg,
101 		u16 first_offset,
102 		int flags)
103 {
104 	int sendpage_flags = flags | MSG_SENDPAGE_NOTLAST;
105 	int ret = 0;
106 	struct page *p;
107 	size_t size;
108 	int offset = first_offset;
109 
110 	size = sg->length - offset;
111 	offset += sg->offset;
112 
113 	ctx->in_tcp_sendpages = true;
114 	while (1) {
115 		if (sg_is_last(sg))
116 			sendpage_flags = flags;
117 
118 		/* is sending application-limited? */
119 		tcp_rate_check_app_limited(sk);
120 		p = sg_page(sg);
121 retry:
122 		ret = do_tcp_sendpages(sk, p, offset, size, sendpage_flags);
123 
124 		if (ret != size) {
125 			if (ret > 0) {
126 				offset += ret;
127 				size -= ret;
128 				goto retry;
129 			}
130 
131 			offset -= sg->offset;
132 			ctx->partially_sent_offset = offset;
133 			ctx->partially_sent_record = (void *)sg;
134 			ctx->in_tcp_sendpages = false;
135 			return ret;
136 		}
137 
138 		put_page(p);
139 		sk_mem_uncharge(sk, sg->length);
140 		sg = sg_next(sg);
141 		if (!sg)
142 			break;
143 
144 		offset = sg->offset;
145 		size = sg->length;
146 	}
147 
148 	ctx->in_tcp_sendpages = false;
149 
150 	return 0;
151 }
152 
153 static int tls_handle_open_record(struct sock *sk, int flags)
154 {
155 	struct tls_context *ctx = tls_get_ctx(sk);
156 
157 	if (tls_is_pending_open_record(ctx))
158 		return ctx->push_pending_record(sk, flags);
159 
160 	return 0;
161 }
162 
163 int tls_proccess_cmsg(struct sock *sk, struct msghdr *msg,
164 		      unsigned char *record_type)
165 {
166 	struct cmsghdr *cmsg;
167 	int rc = -EINVAL;
168 
169 	for_each_cmsghdr(cmsg, msg) {
170 		if (!CMSG_OK(msg, cmsg))
171 			return -EINVAL;
172 		if (cmsg->cmsg_level != SOL_TLS)
173 			continue;
174 
175 		switch (cmsg->cmsg_type) {
176 		case TLS_SET_RECORD_TYPE:
177 			if (cmsg->cmsg_len < CMSG_LEN(sizeof(*record_type)))
178 				return -EINVAL;
179 
180 			if (msg->msg_flags & MSG_MORE)
181 				return -EINVAL;
182 
183 			rc = tls_handle_open_record(sk, msg->msg_flags);
184 			if (rc)
185 				return rc;
186 
187 			*record_type = *(unsigned char *)CMSG_DATA(cmsg);
188 			rc = 0;
189 			break;
190 		default:
191 			return -EINVAL;
192 		}
193 	}
194 
195 	return rc;
196 }
197 
198 int tls_push_partial_record(struct sock *sk, struct tls_context *ctx,
199 			    int flags)
200 {
201 	struct scatterlist *sg;
202 	u16 offset;
203 
204 	sg = ctx->partially_sent_record;
205 	offset = ctx->partially_sent_offset;
206 
207 	ctx->partially_sent_record = NULL;
208 	return tls_push_sg(sk, ctx, sg, offset, flags);
209 }
210 
211 bool tls_free_partial_record(struct sock *sk, struct tls_context *ctx)
212 {
213 	struct scatterlist *sg;
214 
215 	sg = ctx->partially_sent_record;
216 	if (!sg)
217 		return false;
218 
219 	while (1) {
220 		put_page(sg_page(sg));
221 		sk_mem_uncharge(sk, sg->length);
222 
223 		if (sg_is_last(sg))
224 			break;
225 		sg++;
226 	}
227 	ctx->partially_sent_record = NULL;
228 	return true;
229 }
230 
231 static void tls_write_space(struct sock *sk)
232 {
233 	struct tls_context *ctx = tls_get_ctx(sk);
234 
235 	/* If in_tcp_sendpages call lower protocol write space handler
236 	 * to ensure we wake up any waiting operations there. For example
237 	 * if do_tcp_sendpages where to call sk_wait_event.
238 	 */
239 	if (ctx->in_tcp_sendpages) {
240 		ctx->sk_write_space(sk);
241 		return;
242 	}
243 
244 #ifdef CONFIG_TLS_DEVICE
245 	if (ctx->tx_conf == TLS_HW)
246 		tls_device_write_space(sk, ctx);
247 	else
248 #endif
249 		tls_sw_write_space(sk, ctx);
250 
251 	ctx->sk_write_space(sk);
252 }
253 
254 void tls_ctx_free(struct tls_context *ctx)
255 {
256 	if (!ctx)
257 		return;
258 
259 	memzero_explicit(&ctx->crypto_send, sizeof(ctx->crypto_send));
260 	memzero_explicit(&ctx->crypto_recv, sizeof(ctx->crypto_recv));
261 	kfree(ctx);
262 }
263 
264 static void tls_sk_proto_cleanup(struct sock *sk,
265 				 struct tls_context *ctx, long timeo)
266 {
267 	if (unlikely(sk->sk_write_pending) &&
268 	    !wait_on_pending_writer(sk, &timeo))
269 		tls_handle_open_record(sk, 0);
270 
271 	/* We need these for tls_sw_fallback handling of other packets */
272 	if (ctx->tx_conf == TLS_SW) {
273 		kfree(ctx->tx.rec_seq);
274 		kfree(ctx->tx.iv);
275 		tls_sw_release_resources_tx(sk);
276 #ifdef CONFIG_TLS_DEVICE
277 	} else if (ctx->tx_conf == TLS_HW) {
278 		tls_device_free_resources_tx(sk);
279 #endif
280 	}
281 
282 	if (ctx->rx_conf == TLS_SW)
283 		tls_sw_release_resources_rx(sk);
284 
285 #ifdef CONFIG_TLS_DEVICE
286 	if (ctx->rx_conf == TLS_HW)
287 		tls_device_offload_cleanup_rx(sk);
288 #endif
289 }
290 
291 static void tls_sk_proto_close(struct sock *sk, long timeout)
292 {
293 	struct inet_connection_sock *icsk = inet_csk(sk);
294 	struct tls_context *ctx = tls_get_ctx(sk);
295 	long timeo = sock_sndtimeo(sk, 0);
296 	bool free_ctx;
297 
298 	if (ctx->tx_conf == TLS_SW)
299 		tls_sw_cancel_work_tx(ctx);
300 
301 	lock_sock(sk);
302 	free_ctx = ctx->tx_conf != TLS_HW && ctx->rx_conf != TLS_HW;
303 
304 	if (ctx->tx_conf != TLS_BASE || ctx->rx_conf != TLS_BASE)
305 		tls_sk_proto_cleanup(sk, ctx, timeo);
306 
307 	write_lock_bh(&sk->sk_callback_lock);
308 	if (free_ctx)
309 		icsk->icsk_ulp_data = NULL;
310 	sk->sk_prot = ctx->sk_proto;
311 	if (sk->sk_write_space == tls_write_space)
312 		sk->sk_write_space = ctx->sk_write_space;
313 	write_unlock_bh(&sk->sk_callback_lock);
314 	release_sock(sk);
315 	if (ctx->tx_conf == TLS_SW)
316 		tls_sw_free_ctx_tx(ctx);
317 	if (ctx->rx_conf == TLS_SW || ctx->rx_conf == TLS_HW)
318 		tls_sw_strparser_done(ctx);
319 	if (ctx->rx_conf == TLS_SW)
320 		tls_sw_free_ctx_rx(ctx);
321 	ctx->sk_proto_close(sk, timeout);
322 
323 	if (free_ctx)
324 		tls_ctx_free(ctx);
325 }
326 
327 static int do_tls_getsockopt_tx(struct sock *sk, char __user *optval,
328 				int __user *optlen)
329 {
330 	int rc = 0;
331 	struct tls_context *ctx = tls_get_ctx(sk);
332 	struct tls_crypto_info *crypto_info;
333 	int len;
334 
335 	if (get_user(len, optlen))
336 		return -EFAULT;
337 
338 	if (!optval || (len < sizeof(*crypto_info))) {
339 		rc = -EINVAL;
340 		goto out;
341 	}
342 
343 	if (!ctx) {
344 		rc = -EBUSY;
345 		goto out;
346 	}
347 
348 	/* get user crypto info */
349 	crypto_info = &ctx->crypto_send.info;
350 
351 	if (!TLS_CRYPTO_INFO_READY(crypto_info)) {
352 		rc = -EBUSY;
353 		goto out;
354 	}
355 
356 	if (len == sizeof(*crypto_info)) {
357 		if (copy_to_user(optval, crypto_info, sizeof(*crypto_info)))
358 			rc = -EFAULT;
359 		goto out;
360 	}
361 
362 	switch (crypto_info->cipher_type) {
363 	case TLS_CIPHER_AES_GCM_128: {
364 		struct tls12_crypto_info_aes_gcm_128 *
365 		  crypto_info_aes_gcm_128 =
366 		  container_of(crypto_info,
367 			       struct tls12_crypto_info_aes_gcm_128,
368 			       info);
369 
370 		if (len != sizeof(*crypto_info_aes_gcm_128)) {
371 			rc = -EINVAL;
372 			goto out;
373 		}
374 		lock_sock(sk);
375 		memcpy(crypto_info_aes_gcm_128->iv,
376 		       ctx->tx.iv + TLS_CIPHER_AES_GCM_128_SALT_SIZE,
377 		       TLS_CIPHER_AES_GCM_128_IV_SIZE);
378 		memcpy(crypto_info_aes_gcm_128->rec_seq, ctx->tx.rec_seq,
379 		       TLS_CIPHER_AES_GCM_128_REC_SEQ_SIZE);
380 		release_sock(sk);
381 		if (copy_to_user(optval,
382 				 crypto_info_aes_gcm_128,
383 				 sizeof(*crypto_info_aes_gcm_128)))
384 			rc = -EFAULT;
385 		break;
386 	}
387 	case TLS_CIPHER_AES_GCM_256: {
388 		struct tls12_crypto_info_aes_gcm_256 *
389 		  crypto_info_aes_gcm_256 =
390 		  container_of(crypto_info,
391 			       struct tls12_crypto_info_aes_gcm_256,
392 			       info);
393 
394 		if (len != sizeof(*crypto_info_aes_gcm_256)) {
395 			rc = -EINVAL;
396 			goto out;
397 		}
398 		lock_sock(sk);
399 		memcpy(crypto_info_aes_gcm_256->iv,
400 		       ctx->tx.iv + TLS_CIPHER_AES_GCM_256_SALT_SIZE,
401 		       TLS_CIPHER_AES_GCM_256_IV_SIZE);
402 		memcpy(crypto_info_aes_gcm_256->rec_seq, ctx->tx.rec_seq,
403 		       TLS_CIPHER_AES_GCM_256_REC_SEQ_SIZE);
404 		release_sock(sk);
405 		if (copy_to_user(optval,
406 				 crypto_info_aes_gcm_256,
407 				 sizeof(*crypto_info_aes_gcm_256)))
408 			rc = -EFAULT;
409 		break;
410 	}
411 	default:
412 		rc = -EINVAL;
413 	}
414 
415 out:
416 	return rc;
417 }
418 
419 static int do_tls_getsockopt(struct sock *sk, int optname,
420 			     char __user *optval, int __user *optlen)
421 {
422 	int rc = 0;
423 
424 	switch (optname) {
425 	case TLS_TX:
426 		rc = do_tls_getsockopt_tx(sk, optval, optlen);
427 		break;
428 	default:
429 		rc = -ENOPROTOOPT;
430 		break;
431 	}
432 	return rc;
433 }
434 
435 static int tls_getsockopt(struct sock *sk, int level, int optname,
436 			  char __user *optval, int __user *optlen)
437 {
438 	struct tls_context *ctx = tls_get_ctx(sk);
439 
440 	if (level != SOL_TLS)
441 		return ctx->getsockopt(sk, level, optname, optval, optlen);
442 
443 	return do_tls_getsockopt(sk, optname, optval, optlen);
444 }
445 
446 static int do_tls_setsockopt_conf(struct sock *sk, char __user *optval,
447 				  unsigned int optlen, int tx)
448 {
449 	struct tls_crypto_info *crypto_info;
450 	struct tls_crypto_info *alt_crypto_info;
451 	struct tls_context *ctx = tls_get_ctx(sk);
452 	size_t optsize;
453 	int rc = 0;
454 	int conf;
455 
456 	if (!optval || (optlen < sizeof(*crypto_info))) {
457 		rc = -EINVAL;
458 		goto out;
459 	}
460 
461 	if (tx) {
462 		crypto_info = &ctx->crypto_send.info;
463 		alt_crypto_info = &ctx->crypto_recv.info;
464 	} else {
465 		crypto_info = &ctx->crypto_recv.info;
466 		alt_crypto_info = &ctx->crypto_send.info;
467 	}
468 
469 	/* Currently we don't support set crypto info more than one time */
470 	if (TLS_CRYPTO_INFO_READY(crypto_info)) {
471 		rc = -EBUSY;
472 		goto out;
473 	}
474 
475 	rc = copy_from_user(crypto_info, optval, sizeof(*crypto_info));
476 	if (rc) {
477 		rc = -EFAULT;
478 		goto err_crypto_info;
479 	}
480 
481 	/* check version */
482 	if (crypto_info->version != TLS_1_2_VERSION &&
483 	    crypto_info->version != TLS_1_3_VERSION) {
484 		rc = -ENOTSUPP;
485 		goto err_crypto_info;
486 	}
487 
488 	/* Ensure that TLS version and ciphers are same in both directions */
489 	if (TLS_CRYPTO_INFO_READY(alt_crypto_info)) {
490 		if (alt_crypto_info->version != crypto_info->version ||
491 		    alt_crypto_info->cipher_type != crypto_info->cipher_type) {
492 			rc = -EINVAL;
493 			goto err_crypto_info;
494 		}
495 	}
496 
497 	switch (crypto_info->cipher_type) {
498 	case TLS_CIPHER_AES_GCM_128:
499 		optsize = sizeof(struct tls12_crypto_info_aes_gcm_128);
500 		break;
501 	case TLS_CIPHER_AES_GCM_256: {
502 		optsize = sizeof(struct tls12_crypto_info_aes_gcm_256);
503 		break;
504 	}
505 	case TLS_CIPHER_AES_CCM_128:
506 		optsize = sizeof(struct tls12_crypto_info_aes_ccm_128);
507 		break;
508 	default:
509 		rc = -EINVAL;
510 		goto err_crypto_info;
511 	}
512 
513 	if (optlen != optsize) {
514 		rc = -EINVAL;
515 		goto err_crypto_info;
516 	}
517 
518 	rc = copy_from_user(crypto_info + 1, optval + sizeof(*crypto_info),
519 			    optlen - sizeof(*crypto_info));
520 	if (rc) {
521 		rc = -EFAULT;
522 		goto err_crypto_info;
523 	}
524 
525 	if (tx) {
526 #ifdef CONFIG_TLS_DEVICE
527 		rc = tls_set_device_offload(sk, ctx);
528 		conf = TLS_HW;
529 		if (rc) {
530 #else
531 		{
532 #endif
533 			rc = tls_set_sw_offload(sk, ctx, 1);
534 			if (rc)
535 				goto err_crypto_info;
536 			conf = TLS_SW;
537 		}
538 	} else {
539 #ifdef CONFIG_TLS_DEVICE
540 		rc = tls_set_device_offload_rx(sk, ctx);
541 		conf = TLS_HW;
542 		if (rc) {
543 #else
544 		{
545 #endif
546 			rc = tls_set_sw_offload(sk, ctx, 0);
547 			if (rc)
548 				goto err_crypto_info;
549 			conf = TLS_SW;
550 		}
551 		tls_sw_strparser_arm(sk, ctx);
552 	}
553 
554 	if (tx)
555 		ctx->tx_conf = conf;
556 	else
557 		ctx->rx_conf = conf;
558 	update_sk_prot(sk, ctx);
559 	if (tx) {
560 		ctx->sk_write_space = sk->sk_write_space;
561 		sk->sk_write_space = tls_write_space;
562 	} else {
563 		sk->sk_socket->ops = &tls_sw_proto_ops;
564 	}
565 	goto out;
566 
567 err_crypto_info:
568 	memzero_explicit(crypto_info, sizeof(union tls_crypto_context));
569 out:
570 	return rc;
571 }
572 
573 static int do_tls_setsockopt(struct sock *sk, int optname,
574 			     char __user *optval, unsigned int optlen)
575 {
576 	int rc = 0;
577 
578 	switch (optname) {
579 	case TLS_TX:
580 	case TLS_RX:
581 		lock_sock(sk);
582 		rc = do_tls_setsockopt_conf(sk, optval, optlen,
583 					    optname == TLS_TX);
584 		release_sock(sk);
585 		break;
586 	default:
587 		rc = -ENOPROTOOPT;
588 		break;
589 	}
590 	return rc;
591 }
592 
593 static int tls_setsockopt(struct sock *sk, int level, int optname,
594 			  char __user *optval, unsigned int optlen)
595 {
596 	struct tls_context *ctx = tls_get_ctx(sk);
597 
598 	if (level != SOL_TLS)
599 		return ctx->setsockopt(sk, level, optname, optval, optlen);
600 
601 	return do_tls_setsockopt(sk, optname, optval, optlen);
602 }
603 
604 static struct tls_context *create_ctx(struct sock *sk)
605 {
606 	struct inet_connection_sock *icsk = inet_csk(sk);
607 	struct tls_context *ctx;
608 
609 	ctx = kzalloc(sizeof(*ctx), GFP_ATOMIC);
610 	if (!ctx)
611 		return NULL;
612 
613 	icsk->icsk_ulp_data = ctx;
614 	ctx->setsockopt = sk->sk_prot->setsockopt;
615 	ctx->getsockopt = sk->sk_prot->getsockopt;
616 	ctx->sk_proto_close = sk->sk_prot->close;
617 	ctx->unhash = sk->sk_prot->unhash;
618 	return ctx;
619 }
620 
621 static void tls_build_proto(struct sock *sk)
622 {
623 	int ip_ver = sk->sk_family == AF_INET6 ? TLSV6 : TLSV4;
624 
625 	/* Build IPv6 TLS whenever the address of tcpv6 _prot changes */
626 	if (ip_ver == TLSV6 &&
627 	    unlikely(sk->sk_prot != smp_load_acquire(&saved_tcpv6_prot))) {
628 		mutex_lock(&tcpv6_prot_mutex);
629 		if (likely(sk->sk_prot != saved_tcpv6_prot)) {
630 			build_protos(tls_prots[TLSV6], sk->sk_prot);
631 			smp_store_release(&saved_tcpv6_prot, sk->sk_prot);
632 		}
633 		mutex_unlock(&tcpv6_prot_mutex);
634 	}
635 
636 	if (ip_ver == TLSV4 &&
637 	    unlikely(sk->sk_prot != smp_load_acquire(&saved_tcpv4_prot))) {
638 		mutex_lock(&tcpv4_prot_mutex);
639 		if (likely(sk->sk_prot != saved_tcpv4_prot)) {
640 			build_protos(tls_prots[TLSV4], sk->sk_prot);
641 			smp_store_release(&saved_tcpv4_prot, sk->sk_prot);
642 		}
643 		mutex_unlock(&tcpv4_prot_mutex);
644 	}
645 }
646 
647 static void tls_hw_sk_destruct(struct sock *sk)
648 {
649 	struct tls_context *ctx = tls_get_ctx(sk);
650 	struct inet_connection_sock *icsk = inet_csk(sk);
651 
652 	ctx->sk_destruct(sk);
653 	/* Free ctx */
654 	tls_ctx_free(ctx);
655 	icsk->icsk_ulp_data = NULL;
656 }
657 
658 static int tls_hw_prot(struct sock *sk)
659 {
660 	struct tls_context *ctx;
661 	struct tls_device *dev;
662 	int rc = 0;
663 
664 	spin_lock_bh(&device_spinlock);
665 	list_for_each_entry(dev, &device_list, dev_list) {
666 		if (dev->feature && dev->feature(dev)) {
667 			ctx = create_ctx(sk);
668 			if (!ctx)
669 				goto out;
670 
671 			spin_unlock_bh(&device_spinlock);
672 			tls_build_proto(sk);
673 			ctx->hash = sk->sk_prot->hash;
674 			ctx->unhash = sk->sk_prot->unhash;
675 			ctx->sk_proto_close = sk->sk_prot->close;
676 			ctx->sk_destruct = sk->sk_destruct;
677 			sk->sk_destruct = tls_hw_sk_destruct;
678 			ctx->rx_conf = TLS_HW_RECORD;
679 			ctx->tx_conf = TLS_HW_RECORD;
680 			update_sk_prot(sk, ctx);
681 			spin_lock_bh(&device_spinlock);
682 			rc = 1;
683 			break;
684 		}
685 	}
686 out:
687 	spin_unlock_bh(&device_spinlock);
688 	return rc;
689 }
690 
691 static void tls_hw_unhash(struct sock *sk)
692 {
693 	struct tls_context *ctx = tls_get_ctx(sk);
694 	struct tls_device *dev;
695 
696 	spin_lock_bh(&device_spinlock);
697 	list_for_each_entry(dev, &device_list, dev_list) {
698 		if (dev->unhash) {
699 			kref_get(&dev->kref);
700 			spin_unlock_bh(&device_spinlock);
701 			dev->unhash(dev, sk);
702 			kref_put(&dev->kref, dev->release);
703 			spin_lock_bh(&device_spinlock);
704 		}
705 	}
706 	spin_unlock_bh(&device_spinlock);
707 	ctx->unhash(sk);
708 }
709 
710 static int tls_hw_hash(struct sock *sk)
711 {
712 	struct tls_context *ctx = tls_get_ctx(sk);
713 	struct tls_device *dev;
714 	int err;
715 
716 	err = ctx->hash(sk);
717 	spin_lock_bh(&device_spinlock);
718 	list_for_each_entry(dev, &device_list, dev_list) {
719 		if (dev->hash) {
720 			kref_get(&dev->kref);
721 			spin_unlock_bh(&device_spinlock);
722 			err |= dev->hash(dev, sk);
723 			kref_put(&dev->kref, dev->release);
724 			spin_lock_bh(&device_spinlock);
725 		}
726 	}
727 	spin_unlock_bh(&device_spinlock);
728 
729 	if (err)
730 		tls_hw_unhash(sk);
731 	return err;
732 }
733 
734 static void build_protos(struct proto prot[TLS_NUM_CONFIG][TLS_NUM_CONFIG],
735 			 struct proto *base)
736 {
737 	prot[TLS_BASE][TLS_BASE] = *base;
738 	prot[TLS_BASE][TLS_BASE].setsockopt	= tls_setsockopt;
739 	prot[TLS_BASE][TLS_BASE].getsockopt	= tls_getsockopt;
740 	prot[TLS_BASE][TLS_BASE].close		= tls_sk_proto_close;
741 
742 	prot[TLS_SW][TLS_BASE] = prot[TLS_BASE][TLS_BASE];
743 	prot[TLS_SW][TLS_BASE].sendmsg		= tls_sw_sendmsg;
744 	prot[TLS_SW][TLS_BASE].sendpage		= tls_sw_sendpage;
745 
746 	prot[TLS_BASE][TLS_SW] = prot[TLS_BASE][TLS_BASE];
747 	prot[TLS_BASE][TLS_SW].recvmsg		  = tls_sw_recvmsg;
748 	prot[TLS_BASE][TLS_SW].stream_memory_read = tls_sw_stream_read;
749 	prot[TLS_BASE][TLS_SW].close		  = tls_sk_proto_close;
750 
751 	prot[TLS_SW][TLS_SW] = prot[TLS_SW][TLS_BASE];
752 	prot[TLS_SW][TLS_SW].recvmsg		= tls_sw_recvmsg;
753 	prot[TLS_SW][TLS_SW].stream_memory_read	= tls_sw_stream_read;
754 	prot[TLS_SW][TLS_SW].close		= tls_sk_proto_close;
755 
756 #ifdef CONFIG_TLS_DEVICE
757 	prot[TLS_HW][TLS_BASE] = prot[TLS_BASE][TLS_BASE];
758 	prot[TLS_HW][TLS_BASE].sendmsg		= tls_device_sendmsg;
759 	prot[TLS_HW][TLS_BASE].sendpage		= tls_device_sendpage;
760 
761 	prot[TLS_HW][TLS_SW] = prot[TLS_BASE][TLS_SW];
762 	prot[TLS_HW][TLS_SW].sendmsg		= tls_device_sendmsg;
763 	prot[TLS_HW][TLS_SW].sendpage		= tls_device_sendpage;
764 
765 	prot[TLS_BASE][TLS_HW] = prot[TLS_BASE][TLS_SW];
766 
767 	prot[TLS_SW][TLS_HW] = prot[TLS_SW][TLS_SW];
768 
769 	prot[TLS_HW][TLS_HW] = prot[TLS_HW][TLS_SW];
770 #endif
771 
772 	prot[TLS_HW_RECORD][TLS_HW_RECORD] = *base;
773 	prot[TLS_HW_RECORD][TLS_HW_RECORD].hash		= tls_hw_hash;
774 	prot[TLS_HW_RECORD][TLS_HW_RECORD].unhash	= tls_hw_unhash;
775 }
776 
777 static int tls_init(struct sock *sk)
778 {
779 	struct tls_context *ctx;
780 	int rc = 0;
781 
782 	if (tls_hw_prot(sk))
783 		return 0;
784 
785 	/* The TLS ulp is currently supported only for TCP sockets
786 	 * in ESTABLISHED state.
787 	 * Supporting sockets in LISTEN state will require us
788 	 * to modify the accept implementation to clone rather then
789 	 * share the ulp context.
790 	 */
791 	if (sk->sk_state != TCP_ESTABLISHED)
792 		return -ENOTSUPP;
793 
794 	tls_build_proto(sk);
795 
796 	/* allocate tls context */
797 	write_lock_bh(&sk->sk_callback_lock);
798 	ctx = create_ctx(sk);
799 	if (!ctx) {
800 		rc = -ENOMEM;
801 		goto out;
802 	}
803 
804 	ctx->tx_conf = TLS_BASE;
805 	ctx->rx_conf = TLS_BASE;
806 	ctx->sk_proto = sk->sk_prot;
807 	update_sk_prot(sk, ctx);
808 out:
809 	write_unlock_bh(&sk->sk_callback_lock);
810 	return rc;
811 }
812 
813 static void tls_update(struct sock *sk, struct proto *p)
814 {
815 	struct tls_context *ctx;
816 
817 	ctx = tls_get_ctx(sk);
818 	if (likely(ctx)) {
819 		ctx->sk_proto_close = p->close;
820 		ctx->sk_proto = p;
821 	} else {
822 		sk->sk_prot = p;
823 	}
824 }
825 
826 void tls_register_device(struct tls_device *device)
827 {
828 	spin_lock_bh(&device_spinlock);
829 	list_add_tail(&device->dev_list, &device_list);
830 	spin_unlock_bh(&device_spinlock);
831 }
832 EXPORT_SYMBOL(tls_register_device);
833 
834 void tls_unregister_device(struct tls_device *device)
835 {
836 	spin_lock_bh(&device_spinlock);
837 	list_del(&device->dev_list);
838 	spin_unlock_bh(&device_spinlock);
839 }
840 EXPORT_SYMBOL(tls_unregister_device);
841 
842 static struct tcp_ulp_ops tcp_tls_ulp_ops __read_mostly = {
843 	.name			= "tls",
844 	.owner			= THIS_MODULE,
845 	.init			= tls_init,
846 	.update			= tls_update,
847 };
848 
849 static int __init tls_register(void)
850 {
851 	tls_sw_proto_ops = inet_stream_ops;
852 	tls_sw_proto_ops.splice_read = tls_sw_splice_read;
853 
854 #ifdef CONFIG_TLS_DEVICE
855 	tls_device_init();
856 #endif
857 	tcp_register_ulp(&tcp_tls_ulp_ops);
858 
859 	return 0;
860 }
861 
862 static void __exit tls_unregister(void)
863 {
864 	tcp_unregister_ulp(&tcp_tls_ulp_ops);
865 #ifdef CONFIG_TLS_DEVICE
866 	tls_device_cleanup();
867 #endif
868 }
869 
870 module_init(tls_register);
871 module_exit(tls_unregister);
872