xref: /openbmc/linux/net/tls/tls_main.c (revision 3557b3fd)
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 static 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_close(struct sock *sk, long timeout)
265 {
266 	struct tls_context *ctx = tls_get_ctx(sk);
267 	long timeo = sock_sndtimeo(sk, 0);
268 	void (*sk_proto_close)(struct sock *sk, long timeout);
269 	bool free_ctx = false;
270 
271 	lock_sock(sk);
272 	sk_proto_close = ctx->sk_proto_close;
273 
274 	if (ctx->tx_conf == TLS_HW_RECORD && ctx->rx_conf == TLS_HW_RECORD)
275 		goto skip_tx_cleanup;
276 
277 	if (ctx->tx_conf == TLS_BASE && ctx->rx_conf == TLS_BASE) {
278 		free_ctx = true;
279 		goto skip_tx_cleanup;
280 	}
281 
282 	if (!tls_complete_pending_work(sk, ctx, 0, &timeo))
283 		tls_handle_open_record(sk, 0);
284 
285 	/* We need these for tls_sw_fallback handling of other packets */
286 	if (ctx->tx_conf == TLS_SW) {
287 		kfree(ctx->tx.rec_seq);
288 		kfree(ctx->tx.iv);
289 		tls_sw_free_resources_tx(sk);
290 #ifdef CONFIG_TLS_DEVICE
291 	} else if (ctx->tx_conf == TLS_HW) {
292 		tls_device_free_resources_tx(sk);
293 #endif
294 	}
295 
296 	if (ctx->rx_conf == TLS_SW) {
297 		kfree(ctx->rx.rec_seq);
298 		kfree(ctx->rx.iv);
299 		tls_sw_free_resources_rx(sk);
300 	}
301 
302 #ifdef CONFIG_TLS_DEVICE
303 	if (ctx->rx_conf == TLS_HW)
304 		tls_device_offload_cleanup_rx(sk);
305 
306 	if (ctx->tx_conf != TLS_HW && ctx->rx_conf != TLS_HW) {
307 #else
308 	{
309 #endif
310 		tls_ctx_free(ctx);
311 		ctx = NULL;
312 	}
313 
314 skip_tx_cleanup:
315 	release_sock(sk);
316 	sk_proto_close(sk, timeout);
317 	/* free ctx for TLS_HW_RECORD, used by tcp_set_state
318 	 * for sk->sk_prot->unhash [tls_hw_unhash]
319 	 */
320 	if (free_ctx)
321 		tls_ctx_free(ctx);
322 }
323 
324 static int do_tls_getsockopt_tx(struct sock *sk, char __user *optval,
325 				int __user *optlen)
326 {
327 	int rc = 0;
328 	struct tls_context *ctx = tls_get_ctx(sk);
329 	struct tls_crypto_info *crypto_info;
330 	int len;
331 
332 	if (get_user(len, optlen))
333 		return -EFAULT;
334 
335 	if (!optval || (len < sizeof(*crypto_info))) {
336 		rc = -EINVAL;
337 		goto out;
338 	}
339 
340 	if (!ctx) {
341 		rc = -EBUSY;
342 		goto out;
343 	}
344 
345 	/* get user crypto info */
346 	crypto_info = &ctx->crypto_send.info;
347 
348 	if (!TLS_CRYPTO_INFO_READY(crypto_info)) {
349 		rc = -EBUSY;
350 		goto out;
351 	}
352 
353 	if (len == sizeof(*crypto_info)) {
354 		if (copy_to_user(optval, crypto_info, sizeof(*crypto_info)))
355 			rc = -EFAULT;
356 		goto out;
357 	}
358 
359 	switch (crypto_info->cipher_type) {
360 	case TLS_CIPHER_AES_GCM_128: {
361 		struct tls12_crypto_info_aes_gcm_128 *
362 		  crypto_info_aes_gcm_128 =
363 		  container_of(crypto_info,
364 			       struct tls12_crypto_info_aes_gcm_128,
365 			       info);
366 
367 		if (len != sizeof(*crypto_info_aes_gcm_128)) {
368 			rc = -EINVAL;
369 			goto out;
370 		}
371 		lock_sock(sk);
372 		memcpy(crypto_info_aes_gcm_128->iv,
373 		       ctx->tx.iv + TLS_CIPHER_AES_GCM_128_SALT_SIZE,
374 		       TLS_CIPHER_AES_GCM_128_IV_SIZE);
375 		memcpy(crypto_info_aes_gcm_128->rec_seq, ctx->tx.rec_seq,
376 		       TLS_CIPHER_AES_GCM_128_REC_SEQ_SIZE);
377 		release_sock(sk);
378 		if (copy_to_user(optval,
379 				 crypto_info_aes_gcm_128,
380 				 sizeof(*crypto_info_aes_gcm_128)))
381 			rc = -EFAULT;
382 		break;
383 	}
384 	case TLS_CIPHER_AES_GCM_256: {
385 		struct tls12_crypto_info_aes_gcm_256 *
386 		  crypto_info_aes_gcm_256 =
387 		  container_of(crypto_info,
388 			       struct tls12_crypto_info_aes_gcm_256,
389 			       info);
390 
391 		if (len != sizeof(*crypto_info_aes_gcm_256)) {
392 			rc = -EINVAL;
393 			goto out;
394 		}
395 		lock_sock(sk);
396 		memcpy(crypto_info_aes_gcm_256->iv,
397 		       ctx->tx.iv + TLS_CIPHER_AES_GCM_256_SALT_SIZE,
398 		       TLS_CIPHER_AES_GCM_256_IV_SIZE);
399 		memcpy(crypto_info_aes_gcm_256->rec_seq, ctx->tx.rec_seq,
400 		       TLS_CIPHER_AES_GCM_256_REC_SEQ_SIZE);
401 		release_sock(sk);
402 		if (copy_to_user(optval,
403 				 crypto_info_aes_gcm_256,
404 				 sizeof(*crypto_info_aes_gcm_256)))
405 			rc = -EFAULT;
406 		break;
407 	}
408 	default:
409 		rc = -EINVAL;
410 	}
411 
412 out:
413 	return rc;
414 }
415 
416 static int do_tls_getsockopt(struct sock *sk, int optname,
417 			     char __user *optval, int __user *optlen)
418 {
419 	int rc = 0;
420 
421 	switch (optname) {
422 	case TLS_TX:
423 		rc = do_tls_getsockopt_tx(sk, optval, optlen);
424 		break;
425 	default:
426 		rc = -ENOPROTOOPT;
427 		break;
428 	}
429 	return rc;
430 }
431 
432 static int tls_getsockopt(struct sock *sk, int level, int optname,
433 			  char __user *optval, int __user *optlen)
434 {
435 	struct tls_context *ctx = tls_get_ctx(sk);
436 
437 	if (level != SOL_TLS)
438 		return ctx->getsockopt(sk, level, optname, optval, optlen);
439 
440 	return do_tls_getsockopt(sk, optname, optval, optlen);
441 }
442 
443 static int do_tls_setsockopt_conf(struct sock *sk, char __user *optval,
444 				  unsigned int optlen, int tx)
445 {
446 	struct tls_crypto_info *crypto_info;
447 	struct tls_crypto_info *alt_crypto_info;
448 	struct tls_context *ctx = tls_get_ctx(sk);
449 	size_t optsize;
450 	int rc = 0;
451 	int conf;
452 
453 	if (!optval || (optlen < sizeof(*crypto_info))) {
454 		rc = -EINVAL;
455 		goto out;
456 	}
457 
458 	if (tx) {
459 		crypto_info = &ctx->crypto_send.info;
460 		alt_crypto_info = &ctx->crypto_recv.info;
461 	} else {
462 		crypto_info = &ctx->crypto_recv.info;
463 		alt_crypto_info = &ctx->crypto_send.info;
464 	}
465 
466 	/* Currently we don't support set crypto info more than one time */
467 	if (TLS_CRYPTO_INFO_READY(crypto_info)) {
468 		rc = -EBUSY;
469 		goto out;
470 	}
471 
472 	rc = copy_from_user(crypto_info, optval, sizeof(*crypto_info));
473 	if (rc) {
474 		rc = -EFAULT;
475 		goto err_crypto_info;
476 	}
477 
478 	/* check version */
479 	if (crypto_info->version != TLS_1_2_VERSION &&
480 	    crypto_info->version != TLS_1_3_VERSION) {
481 		rc = -ENOTSUPP;
482 		goto err_crypto_info;
483 	}
484 
485 	/* Ensure that TLS version and ciphers are same in both directions */
486 	if (TLS_CRYPTO_INFO_READY(alt_crypto_info)) {
487 		if (alt_crypto_info->version != crypto_info->version ||
488 		    alt_crypto_info->cipher_type != crypto_info->cipher_type) {
489 			rc = -EINVAL;
490 			goto err_crypto_info;
491 		}
492 	}
493 
494 	switch (crypto_info->cipher_type) {
495 	case TLS_CIPHER_AES_GCM_128:
496 		optsize = sizeof(struct tls12_crypto_info_aes_gcm_128);
497 		break;
498 	case TLS_CIPHER_AES_GCM_256: {
499 		optsize = sizeof(struct tls12_crypto_info_aes_gcm_256);
500 		break;
501 	}
502 	case TLS_CIPHER_AES_CCM_128:
503 		optsize = sizeof(struct tls12_crypto_info_aes_ccm_128);
504 		break;
505 	default:
506 		rc = -EINVAL;
507 		goto err_crypto_info;
508 	}
509 
510 	if (optlen != optsize) {
511 		rc = -EINVAL;
512 		goto err_crypto_info;
513 	}
514 
515 	rc = copy_from_user(crypto_info + 1, optval + sizeof(*crypto_info),
516 			    optlen - sizeof(*crypto_info));
517 	if (rc) {
518 		rc = -EFAULT;
519 		goto err_crypto_info;
520 	}
521 
522 	if (tx) {
523 #ifdef CONFIG_TLS_DEVICE
524 		rc = tls_set_device_offload(sk, ctx);
525 		conf = TLS_HW;
526 		if (rc) {
527 #else
528 		{
529 #endif
530 			rc = tls_set_sw_offload(sk, ctx, 1);
531 			conf = TLS_SW;
532 		}
533 	} else {
534 #ifdef CONFIG_TLS_DEVICE
535 		rc = tls_set_device_offload_rx(sk, ctx);
536 		conf = TLS_HW;
537 		if (rc) {
538 #else
539 		{
540 #endif
541 			rc = tls_set_sw_offload(sk, ctx, 0);
542 			conf = TLS_SW;
543 		}
544 	}
545 
546 	if (rc)
547 		goto err_crypto_info;
548 
549 	if (tx)
550 		ctx->tx_conf = conf;
551 	else
552 		ctx->rx_conf = conf;
553 	update_sk_prot(sk, ctx);
554 	if (tx) {
555 		ctx->sk_write_space = sk->sk_write_space;
556 		sk->sk_write_space = tls_write_space;
557 	} else {
558 		sk->sk_socket->ops = &tls_sw_proto_ops;
559 	}
560 	goto out;
561 
562 err_crypto_info:
563 	memzero_explicit(crypto_info, sizeof(union tls_crypto_context));
564 out:
565 	return rc;
566 }
567 
568 static int do_tls_setsockopt(struct sock *sk, int optname,
569 			     char __user *optval, unsigned int optlen)
570 {
571 	int rc = 0;
572 
573 	switch (optname) {
574 	case TLS_TX:
575 	case TLS_RX:
576 		lock_sock(sk);
577 		rc = do_tls_setsockopt_conf(sk, optval, optlen,
578 					    optname == TLS_TX);
579 		release_sock(sk);
580 		break;
581 	default:
582 		rc = -ENOPROTOOPT;
583 		break;
584 	}
585 	return rc;
586 }
587 
588 static int tls_setsockopt(struct sock *sk, int level, int optname,
589 			  char __user *optval, unsigned int optlen)
590 {
591 	struct tls_context *ctx = tls_get_ctx(sk);
592 
593 	if (level != SOL_TLS)
594 		return ctx->setsockopt(sk, level, optname, optval, optlen);
595 
596 	return do_tls_setsockopt(sk, optname, optval, optlen);
597 }
598 
599 static struct tls_context *create_ctx(struct sock *sk)
600 {
601 	struct inet_connection_sock *icsk = inet_csk(sk);
602 	struct tls_context *ctx;
603 
604 	ctx = kzalloc(sizeof(*ctx), GFP_ATOMIC);
605 	if (!ctx)
606 		return NULL;
607 
608 	icsk->icsk_ulp_data = ctx;
609 	ctx->setsockopt = sk->sk_prot->setsockopt;
610 	ctx->getsockopt = sk->sk_prot->getsockopt;
611 	ctx->sk_proto_close = sk->sk_prot->close;
612 	return ctx;
613 }
614 
615 static void tls_build_proto(struct sock *sk)
616 {
617 	int ip_ver = sk->sk_family == AF_INET6 ? TLSV6 : TLSV4;
618 
619 	/* Build IPv6 TLS whenever the address of tcpv6 _prot changes */
620 	if (ip_ver == TLSV6 &&
621 	    unlikely(sk->sk_prot != smp_load_acquire(&saved_tcpv6_prot))) {
622 		mutex_lock(&tcpv6_prot_mutex);
623 		if (likely(sk->sk_prot != saved_tcpv6_prot)) {
624 			build_protos(tls_prots[TLSV6], sk->sk_prot);
625 			smp_store_release(&saved_tcpv6_prot, sk->sk_prot);
626 		}
627 		mutex_unlock(&tcpv6_prot_mutex);
628 	}
629 
630 	if (ip_ver == TLSV4 &&
631 	    unlikely(sk->sk_prot != smp_load_acquire(&saved_tcpv4_prot))) {
632 		mutex_lock(&tcpv4_prot_mutex);
633 		if (likely(sk->sk_prot != saved_tcpv4_prot)) {
634 			build_protos(tls_prots[TLSV4], sk->sk_prot);
635 			smp_store_release(&saved_tcpv4_prot, sk->sk_prot);
636 		}
637 		mutex_unlock(&tcpv4_prot_mutex);
638 	}
639 }
640 
641 static void tls_hw_sk_destruct(struct sock *sk)
642 {
643 	struct tls_context *ctx = tls_get_ctx(sk);
644 	struct inet_connection_sock *icsk = inet_csk(sk);
645 
646 	ctx->sk_destruct(sk);
647 	/* Free ctx */
648 	kfree(ctx);
649 	icsk->icsk_ulp_data = NULL;
650 }
651 
652 static int tls_hw_prot(struct sock *sk)
653 {
654 	struct tls_context *ctx;
655 	struct tls_device *dev;
656 	int rc = 0;
657 
658 	spin_lock_bh(&device_spinlock);
659 	list_for_each_entry(dev, &device_list, dev_list) {
660 		if (dev->feature && dev->feature(dev)) {
661 			ctx = create_ctx(sk);
662 			if (!ctx)
663 				goto out;
664 
665 			spin_unlock_bh(&device_spinlock);
666 			tls_build_proto(sk);
667 			ctx->hash = sk->sk_prot->hash;
668 			ctx->unhash = sk->sk_prot->unhash;
669 			ctx->sk_proto_close = sk->sk_prot->close;
670 			ctx->sk_destruct = sk->sk_destruct;
671 			sk->sk_destruct = tls_hw_sk_destruct;
672 			ctx->rx_conf = TLS_HW_RECORD;
673 			ctx->tx_conf = TLS_HW_RECORD;
674 			update_sk_prot(sk, ctx);
675 			spin_lock_bh(&device_spinlock);
676 			rc = 1;
677 			break;
678 		}
679 	}
680 out:
681 	spin_unlock_bh(&device_spinlock);
682 	return rc;
683 }
684 
685 static void tls_hw_unhash(struct sock *sk)
686 {
687 	struct tls_context *ctx = tls_get_ctx(sk);
688 	struct tls_device *dev;
689 
690 	spin_lock_bh(&device_spinlock);
691 	list_for_each_entry(dev, &device_list, dev_list) {
692 		if (dev->unhash) {
693 			kref_get(&dev->kref);
694 			spin_unlock_bh(&device_spinlock);
695 			dev->unhash(dev, sk);
696 			kref_put(&dev->kref, dev->release);
697 			spin_lock_bh(&device_spinlock);
698 		}
699 	}
700 	spin_unlock_bh(&device_spinlock);
701 	ctx->unhash(sk);
702 }
703 
704 static int tls_hw_hash(struct sock *sk)
705 {
706 	struct tls_context *ctx = tls_get_ctx(sk);
707 	struct tls_device *dev;
708 	int err;
709 
710 	err = ctx->hash(sk);
711 	spin_lock_bh(&device_spinlock);
712 	list_for_each_entry(dev, &device_list, dev_list) {
713 		if (dev->hash) {
714 			kref_get(&dev->kref);
715 			spin_unlock_bh(&device_spinlock);
716 			err |= dev->hash(dev, sk);
717 			kref_put(&dev->kref, dev->release);
718 			spin_lock_bh(&device_spinlock);
719 		}
720 	}
721 	spin_unlock_bh(&device_spinlock);
722 
723 	if (err)
724 		tls_hw_unhash(sk);
725 	return err;
726 }
727 
728 static void build_protos(struct proto prot[TLS_NUM_CONFIG][TLS_NUM_CONFIG],
729 			 struct proto *base)
730 {
731 	prot[TLS_BASE][TLS_BASE] = *base;
732 	prot[TLS_BASE][TLS_BASE].setsockopt	= tls_setsockopt;
733 	prot[TLS_BASE][TLS_BASE].getsockopt	= tls_getsockopt;
734 	prot[TLS_BASE][TLS_BASE].close		= tls_sk_proto_close;
735 
736 	prot[TLS_SW][TLS_BASE] = prot[TLS_BASE][TLS_BASE];
737 	prot[TLS_SW][TLS_BASE].sendmsg		= tls_sw_sendmsg;
738 	prot[TLS_SW][TLS_BASE].sendpage		= tls_sw_sendpage;
739 
740 	prot[TLS_BASE][TLS_SW] = prot[TLS_BASE][TLS_BASE];
741 	prot[TLS_BASE][TLS_SW].recvmsg		  = tls_sw_recvmsg;
742 	prot[TLS_BASE][TLS_SW].stream_memory_read = tls_sw_stream_read;
743 	prot[TLS_BASE][TLS_SW].close		  = tls_sk_proto_close;
744 
745 	prot[TLS_SW][TLS_SW] = prot[TLS_SW][TLS_BASE];
746 	prot[TLS_SW][TLS_SW].recvmsg		= tls_sw_recvmsg;
747 	prot[TLS_SW][TLS_SW].stream_memory_read	= tls_sw_stream_read;
748 	prot[TLS_SW][TLS_SW].close		= tls_sk_proto_close;
749 
750 #ifdef CONFIG_TLS_DEVICE
751 	prot[TLS_HW][TLS_BASE] = prot[TLS_BASE][TLS_BASE];
752 	prot[TLS_HW][TLS_BASE].sendmsg		= tls_device_sendmsg;
753 	prot[TLS_HW][TLS_BASE].sendpage		= tls_device_sendpage;
754 
755 	prot[TLS_HW][TLS_SW] = prot[TLS_BASE][TLS_SW];
756 	prot[TLS_HW][TLS_SW].sendmsg		= tls_device_sendmsg;
757 	prot[TLS_HW][TLS_SW].sendpage		= tls_device_sendpage;
758 
759 	prot[TLS_BASE][TLS_HW] = prot[TLS_BASE][TLS_SW];
760 
761 	prot[TLS_SW][TLS_HW] = prot[TLS_SW][TLS_SW];
762 
763 	prot[TLS_HW][TLS_HW] = prot[TLS_HW][TLS_SW];
764 #endif
765 
766 	prot[TLS_HW_RECORD][TLS_HW_RECORD] = *base;
767 	prot[TLS_HW_RECORD][TLS_HW_RECORD].hash		= tls_hw_hash;
768 	prot[TLS_HW_RECORD][TLS_HW_RECORD].unhash	= tls_hw_unhash;
769 	prot[TLS_HW_RECORD][TLS_HW_RECORD].close	= tls_sk_proto_close;
770 }
771 
772 static int tls_init(struct sock *sk)
773 {
774 	struct tls_context *ctx;
775 	int rc = 0;
776 
777 	if (tls_hw_prot(sk))
778 		goto out;
779 
780 	/* The TLS ulp is currently supported only for TCP sockets
781 	 * in ESTABLISHED state.
782 	 * Supporting sockets in LISTEN state will require us
783 	 * to modify the accept implementation to clone rather then
784 	 * share the ulp context.
785 	 */
786 	if (sk->sk_state != TCP_ESTABLISHED)
787 		return -ENOTSUPP;
788 
789 	/* allocate tls context */
790 	ctx = create_ctx(sk);
791 	if (!ctx) {
792 		rc = -ENOMEM;
793 		goto out;
794 	}
795 
796 	tls_build_proto(sk);
797 	ctx->tx_conf = TLS_BASE;
798 	ctx->rx_conf = TLS_BASE;
799 	update_sk_prot(sk, ctx);
800 out:
801 	return rc;
802 }
803 
804 void tls_register_device(struct tls_device *device)
805 {
806 	spin_lock_bh(&device_spinlock);
807 	list_add_tail(&device->dev_list, &device_list);
808 	spin_unlock_bh(&device_spinlock);
809 }
810 EXPORT_SYMBOL(tls_register_device);
811 
812 void tls_unregister_device(struct tls_device *device)
813 {
814 	spin_lock_bh(&device_spinlock);
815 	list_del(&device->dev_list);
816 	spin_unlock_bh(&device_spinlock);
817 }
818 EXPORT_SYMBOL(tls_unregister_device);
819 
820 static struct tcp_ulp_ops tcp_tls_ulp_ops __read_mostly = {
821 	.name			= "tls",
822 	.owner			= THIS_MODULE,
823 	.init			= tls_init,
824 };
825 
826 static int __init tls_register(void)
827 {
828 	tls_sw_proto_ops = inet_stream_ops;
829 	tls_sw_proto_ops.splice_read = tls_sw_splice_read;
830 
831 #ifdef CONFIG_TLS_DEVICE
832 	tls_device_init();
833 #endif
834 	tcp_register_ulp(&tcp_tls_ulp_ops);
835 
836 	return 0;
837 }
838 
839 static void __exit tls_unregister(void)
840 {
841 	tcp_unregister_ulp(&tcp_tls_ulp_ops);
842 #ifdef CONFIG_TLS_DEVICE
843 	tls_device_cleanup();
844 #endif
845 }
846 
847 module_init(tls_register);
848 module_exit(tls_unregister);
849