xref: /linux/net/tls/tls_main.c (revision dd5b2498d845f925904cb2afabb6ba11bfc317c5)
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 static void tls_write_space(struct sock *sk)
212 {
213 	struct tls_context *ctx = tls_get_ctx(sk);
214 
215 	/* If in_tcp_sendpages call lower protocol write space handler
216 	 * to ensure we wake up any waiting operations there. For example
217 	 * if do_tcp_sendpages where to call sk_wait_event.
218 	 */
219 	if (ctx->in_tcp_sendpages) {
220 		ctx->sk_write_space(sk);
221 		return;
222 	}
223 
224 #ifdef CONFIG_TLS_DEVICE
225 	if (ctx->tx_conf == TLS_HW)
226 		tls_device_write_space(sk, ctx);
227 	else
228 #endif
229 		tls_sw_write_space(sk, ctx);
230 
231 	ctx->sk_write_space(sk);
232 }
233 
234 static void tls_ctx_free(struct tls_context *ctx)
235 {
236 	if (!ctx)
237 		return;
238 
239 	memzero_explicit(&ctx->crypto_send, sizeof(ctx->crypto_send));
240 	memzero_explicit(&ctx->crypto_recv, sizeof(ctx->crypto_recv));
241 	kfree(ctx);
242 }
243 
244 static void tls_sk_proto_close(struct sock *sk, long timeout)
245 {
246 	struct tls_context *ctx = tls_get_ctx(sk);
247 	long timeo = sock_sndtimeo(sk, 0);
248 	void (*sk_proto_close)(struct sock *sk, long timeout);
249 	bool free_ctx = false;
250 
251 	lock_sock(sk);
252 	sk_proto_close = ctx->sk_proto_close;
253 
254 	if (ctx->tx_conf == TLS_HW_RECORD && ctx->rx_conf == TLS_HW_RECORD)
255 		goto skip_tx_cleanup;
256 
257 	if (ctx->tx_conf == TLS_BASE && ctx->rx_conf == TLS_BASE) {
258 		free_ctx = true;
259 		goto skip_tx_cleanup;
260 	}
261 
262 	if (!tls_complete_pending_work(sk, ctx, 0, &timeo))
263 		tls_handle_open_record(sk, 0);
264 
265 	/* We need these for tls_sw_fallback handling of other packets */
266 	if (ctx->tx_conf == TLS_SW) {
267 		kfree(ctx->tx.rec_seq);
268 		kfree(ctx->tx.iv);
269 		tls_sw_free_resources_tx(sk);
270 	}
271 
272 	if (ctx->rx_conf == TLS_SW) {
273 		kfree(ctx->rx.rec_seq);
274 		kfree(ctx->rx.iv);
275 		tls_sw_free_resources_rx(sk);
276 	}
277 
278 #ifdef CONFIG_TLS_DEVICE
279 	if (ctx->rx_conf == TLS_HW)
280 		tls_device_offload_cleanup_rx(sk);
281 
282 	if (ctx->tx_conf != TLS_HW && ctx->rx_conf != TLS_HW) {
283 #else
284 	{
285 #endif
286 		tls_ctx_free(ctx);
287 		ctx = NULL;
288 	}
289 
290 skip_tx_cleanup:
291 	release_sock(sk);
292 	sk_proto_close(sk, timeout);
293 	/* free ctx for TLS_HW_RECORD, used by tcp_set_state
294 	 * for sk->sk_prot->unhash [tls_hw_unhash]
295 	 */
296 	if (free_ctx)
297 		tls_ctx_free(ctx);
298 }
299 
300 static int do_tls_getsockopt_tx(struct sock *sk, char __user *optval,
301 				int __user *optlen)
302 {
303 	int rc = 0;
304 	struct tls_context *ctx = tls_get_ctx(sk);
305 	struct tls_crypto_info *crypto_info;
306 	int len;
307 
308 	if (get_user(len, optlen))
309 		return -EFAULT;
310 
311 	if (!optval || (len < sizeof(*crypto_info))) {
312 		rc = -EINVAL;
313 		goto out;
314 	}
315 
316 	if (!ctx) {
317 		rc = -EBUSY;
318 		goto out;
319 	}
320 
321 	/* get user crypto info */
322 	crypto_info = &ctx->crypto_send.info;
323 
324 	if (!TLS_CRYPTO_INFO_READY(crypto_info)) {
325 		rc = -EBUSY;
326 		goto out;
327 	}
328 
329 	if (len == sizeof(*crypto_info)) {
330 		if (copy_to_user(optval, crypto_info, sizeof(*crypto_info)))
331 			rc = -EFAULT;
332 		goto out;
333 	}
334 
335 	switch (crypto_info->cipher_type) {
336 	case TLS_CIPHER_AES_GCM_128: {
337 		struct tls12_crypto_info_aes_gcm_128 *
338 		  crypto_info_aes_gcm_128 =
339 		  container_of(crypto_info,
340 			       struct tls12_crypto_info_aes_gcm_128,
341 			       info);
342 
343 		if (len != sizeof(*crypto_info_aes_gcm_128)) {
344 			rc = -EINVAL;
345 			goto out;
346 		}
347 		lock_sock(sk);
348 		memcpy(crypto_info_aes_gcm_128->iv,
349 		       ctx->tx.iv + TLS_CIPHER_AES_GCM_128_SALT_SIZE,
350 		       TLS_CIPHER_AES_GCM_128_IV_SIZE);
351 		memcpy(crypto_info_aes_gcm_128->rec_seq, ctx->tx.rec_seq,
352 		       TLS_CIPHER_AES_GCM_128_REC_SEQ_SIZE);
353 		release_sock(sk);
354 		if (copy_to_user(optval,
355 				 crypto_info_aes_gcm_128,
356 				 sizeof(*crypto_info_aes_gcm_128)))
357 			rc = -EFAULT;
358 		break;
359 	}
360 	case TLS_CIPHER_AES_GCM_256: {
361 		struct tls12_crypto_info_aes_gcm_256 *
362 		  crypto_info_aes_gcm_256 =
363 		  container_of(crypto_info,
364 			       struct tls12_crypto_info_aes_gcm_256,
365 			       info);
366 
367 		if (len != sizeof(*crypto_info_aes_gcm_256)) {
368 			rc = -EINVAL;
369 			goto out;
370 		}
371 		lock_sock(sk);
372 		memcpy(crypto_info_aes_gcm_256->iv,
373 		       ctx->tx.iv + TLS_CIPHER_AES_GCM_256_SALT_SIZE,
374 		       TLS_CIPHER_AES_GCM_256_IV_SIZE);
375 		memcpy(crypto_info_aes_gcm_256->rec_seq, ctx->tx.rec_seq,
376 		       TLS_CIPHER_AES_GCM_256_REC_SEQ_SIZE);
377 		release_sock(sk);
378 		if (copy_to_user(optval,
379 				 crypto_info_aes_gcm_256,
380 				 sizeof(*crypto_info_aes_gcm_256)))
381 			rc = -EFAULT;
382 		break;
383 	}
384 	default:
385 		rc = -EINVAL;
386 	}
387 
388 out:
389 	return rc;
390 }
391 
392 static int do_tls_getsockopt(struct sock *sk, int optname,
393 			     char __user *optval, int __user *optlen)
394 {
395 	int rc = 0;
396 
397 	switch (optname) {
398 	case TLS_TX:
399 		rc = do_tls_getsockopt_tx(sk, optval, optlen);
400 		break;
401 	default:
402 		rc = -ENOPROTOOPT;
403 		break;
404 	}
405 	return rc;
406 }
407 
408 static int tls_getsockopt(struct sock *sk, int level, int optname,
409 			  char __user *optval, int __user *optlen)
410 {
411 	struct tls_context *ctx = tls_get_ctx(sk);
412 
413 	if (level != SOL_TLS)
414 		return ctx->getsockopt(sk, level, optname, optval, optlen);
415 
416 	return do_tls_getsockopt(sk, optname, optval, optlen);
417 }
418 
419 static int do_tls_setsockopt_conf(struct sock *sk, char __user *optval,
420 				  unsigned int optlen, int tx)
421 {
422 	struct tls_crypto_info *crypto_info;
423 	struct tls_crypto_info *alt_crypto_info;
424 	struct tls_context *ctx = tls_get_ctx(sk);
425 	size_t optsize;
426 	int rc = 0;
427 	int conf;
428 
429 	if (!optval || (optlen < sizeof(*crypto_info))) {
430 		rc = -EINVAL;
431 		goto out;
432 	}
433 
434 	if (tx) {
435 		crypto_info = &ctx->crypto_send.info;
436 		alt_crypto_info = &ctx->crypto_recv.info;
437 	} else {
438 		crypto_info = &ctx->crypto_recv.info;
439 		alt_crypto_info = &ctx->crypto_send.info;
440 	}
441 
442 	/* Currently we don't support set crypto info more than one time */
443 	if (TLS_CRYPTO_INFO_READY(crypto_info)) {
444 		rc = -EBUSY;
445 		goto out;
446 	}
447 
448 	rc = copy_from_user(crypto_info, optval, sizeof(*crypto_info));
449 	if (rc) {
450 		rc = -EFAULT;
451 		goto err_crypto_info;
452 	}
453 
454 	/* check version */
455 	if (crypto_info->version != TLS_1_2_VERSION &&
456 	    crypto_info->version != TLS_1_3_VERSION) {
457 		rc = -ENOTSUPP;
458 		goto err_crypto_info;
459 	}
460 
461 	/* Ensure that TLS version and ciphers are same in both directions */
462 	if (TLS_CRYPTO_INFO_READY(alt_crypto_info)) {
463 		if (alt_crypto_info->version != crypto_info->version ||
464 		    alt_crypto_info->cipher_type != crypto_info->cipher_type) {
465 			rc = -EINVAL;
466 			goto err_crypto_info;
467 		}
468 	}
469 
470 	switch (crypto_info->cipher_type) {
471 	case TLS_CIPHER_AES_GCM_128:
472 		optsize = sizeof(struct tls12_crypto_info_aes_gcm_128);
473 		break;
474 	case TLS_CIPHER_AES_GCM_256: {
475 		optsize = sizeof(struct tls12_crypto_info_aes_gcm_256);
476 		break;
477 	}
478 	case TLS_CIPHER_AES_CCM_128:
479 		optsize = sizeof(struct tls12_crypto_info_aes_ccm_128);
480 		break;
481 	default:
482 		rc = -EINVAL;
483 		goto err_crypto_info;
484 	}
485 
486 	if (optlen != optsize) {
487 		rc = -EINVAL;
488 		goto err_crypto_info;
489 	}
490 
491 	rc = copy_from_user(crypto_info + 1, optval + sizeof(*crypto_info),
492 			    optlen - sizeof(*crypto_info));
493 	if (rc) {
494 		rc = -EFAULT;
495 		goto err_crypto_info;
496 	}
497 
498 	if (tx) {
499 #ifdef CONFIG_TLS_DEVICE
500 		rc = tls_set_device_offload(sk, ctx);
501 		conf = TLS_HW;
502 		if (rc) {
503 #else
504 		{
505 #endif
506 			rc = tls_set_sw_offload(sk, ctx, 1);
507 			conf = TLS_SW;
508 		}
509 	} else {
510 #ifdef CONFIG_TLS_DEVICE
511 		rc = tls_set_device_offload_rx(sk, ctx);
512 		conf = TLS_HW;
513 		if (rc) {
514 #else
515 		{
516 #endif
517 			rc = tls_set_sw_offload(sk, ctx, 0);
518 			conf = TLS_SW;
519 		}
520 	}
521 
522 	if (rc)
523 		goto err_crypto_info;
524 
525 	if (tx)
526 		ctx->tx_conf = conf;
527 	else
528 		ctx->rx_conf = conf;
529 	update_sk_prot(sk, ctx);
530 	if (tx) {
531 		ctx->sk_write_space = sk->sk_write_space;
532 		sk->sk_write_space = tls_write_space;
533 	} else {
534 		sk->sk_socket->ops = &tls_sw_proto_ops;
535 	}
536 	goto out;
537 
538 err_crypto_info:
539 	memzero_explicit(crypto_info, sizeof(union tls_crypto_context));
540 out:
541 	return rc;
542 }
543 
544 static int do_tls_setsockopt(struct sock *sk, int optname,
545 			     char __user *optval, unsigned int optlen)
546 {
547 	int rc = 0;
548 
549 	switch (optname) {
550 	case TLS_TX:
551 	case TLS_RX:
552 		lock_sock(sk);
553 		rc = do_tls_setsockopt_conf(sk, optval, optlen,
554 					    optname == TLS_TX);
555 		release_sock(sk);
556 		break;
557 	default:
558 		rc = -ENOPROTOOPT;
559 		break;
560 	}
561 	return rc;
562 }
563 
564 static int tls_setsockopt(struct sock *sk, int level, int optname,
565 			  char __user *optval, unsigned int optlen)
566 {
567 	struct tls_context *ctx = tls_get_ctx(sk);
568 
569 	if (level != SOL_TLS)
570 		return ctx->setsockopt(sk, level, optname, optval, optlen);
571 
572 	return do_tls_setsockopt(sk, optname, optval, optlen);
573 }
574 
575 static struct tls_context *create_ctx(struct sock *sk)
576 {
577 	struct inet_connection_sock *icsk = inet_csk(sk);
578 	struct tls_context *ctx;
579 
580 	ctx = kzalloc(sizeof(*ctx), GFP_ATOMIC);
581 	if (!ctx)
582 		return NULL;
583 
584 	icsk->icsk_ulp_data = ctx;
585 	ctx->setsockopt = sk->sk_prot->setsockopt;
586 	ctx->getsockopt = sk->sk_prot->getsockopt;
587 	ctx->sk_proto_close = sk->sk_prot->close;
588 	return ctx;
589 }
590 
591 static void tls_build_proto(struct sock *sk)
592 {
593 	int ip_ver = sk->sk_family == AF_INET6 ? TLSV6 : TLSV4;
594 
595 	/* Build IPv6 TLS whenever the address of tcpv6 _prot changes */
596 	if (ip_ver == TLSV6 &&
597 	    unlikely(sk->sk_prot != smp_load_acquire(&saved_tcpv6_prot))) {
598 		mutex_lock(&tcpv6_prot_mutex);
599 		if (likely(sk->sk_prot != saved_tcpv6_prot)) {
600 			build_protos(tls_prots[TLSV6], sk->sk_prot);
601 			smp_store_release(&saved_tcpv6_prot, sk->sk_prot);
602 		}
603 		mutex_unlock(&tcpv6_prot_mutex);
604 	}
605 
606 	if (ip_ver == TLSV4 &&
607 	    unlikely(sk->sk_prot != smp_load_acquire(&saved_tcpv4_prot))) {
608 		mutex_lock(&tcpv4_prot_mutex);
609 		if (likely(sk->sk_prot != saved_tcpv4_prot)) {
610 			build_protos(tls_prots[TLSV4], sk->sk_prot);
611 			smp_store_release(&saved_tcpv4_prot, sk->sk_prot);
612 		}
613 		mutex_unlock(&tcpv4_prot_mutex);
614 	}
615 }
616 
617 static void tls_hw_sk_destruct(struct sock *sk)
618 {
619 	struct tls_context *ctx = tls_get_ctx(sk);
620 	struct inet_connection_sock *icsk = inet_csk(sk);
621 
622 	ctx->sk_destruct(sk);
623 	/* Free ctx */
624 	kfree(ctx);
625 	icsk->icsk_ulp_data = NULL;
626 }
627 
628 static int tls_hw_prot(struct sock *sk)
629 {
630 	struct tls_context *ctx;
631 	struct tls_device *dev;
632 	int rc = 0;
633 
634 	spin_lock_bh(&device_spinlock);
635 	list_for_each_entry(dev, &device_list, dev_list) {
636 		if (dev->feature && dev->feature(dev)) {
637 			ctx = create_ctx(sk);
638 			if (!ctx)
639 				goto out;
640 
641 			spin_unlock_bh(&device_spinlock);
642 			tls_build_proto(sk);
643 			ctx->hash = sk->sk_prot->hash;
644 			ctx->unhash = sk->sk_prot->unhash;
645 			ctx->sk_proto_close = sk->sk_prot->close;
646 			ctx->sk_destruct = sk->sk_destruct;
647 			sk->sk_destruct = tls_hw_sk_destruct;
648 			ctx->rx_conf = TLS_HW_RECORD;
649 			ctx->tx_conf = TLS_HW_RECORD;
650 			update_sk_prot(sk, ctx);
651 			spin_lock_bh(&device_spinlock);
652 			rc = 1;
653 			break;
654 		}
655 	}
656 out:
657 	spin_unlock_bh(&device_spinlock);
658 	return rc;
659 }
660 
661 static void tls_hw_unhash(struct sock *sk)
662 {
663 	struct tls_context *ctx = tls_get_ctx(sk);
664 	struct tls_device *dev;
665 
666 	spin_lock_bh(&device_spinlock);
667 	list_for_each_entry(dev, &device_list, dev_list) {
668 		if (dev->unhash) {
669 			kref_get(&dev->kref);
670 			spin_unlock_bh(&device_spinlock);
671 			dev->unhash(dev, sk);
672 			kref_put(&dev->kref, dev->release);
673 			spin_lock_bh(&device_spinlock);
674 		}
675 	}
676 	spin_unlock_bh(&device_spinlock);
677 	ctx->unhash(sk);
678 }
679 
680 static int tls_hw_hash(struct sock *sk)
681 {
682 	struct tls_context *ctx = tls_get_ctx(sk);
683 	struct tls_device *dev;
684 	int err;
685 
686 	err = ctx->hash(sk);
687 	spin_lock_bh(&device_spinlock);
688 	list_for_each_entry(dev, &device_list, dev_list) {
689 		if (dev->hash) {
690 			kref_get(&dev->kref);
691 			spin_unlock_bh(&device_spinlock);
692 			err |= dev->hash(dev, sk);
693 			kref_put(&dev->kref, dev->release);
694 			spin_lock_bh(&device_spinlock);
695 		}
696 	}
697 	spin_unlock_bh(&device_spinlock);
698 
699 	if (err)
700 		tls_hw_unhash(sk);
701 	return err;
702 }
703 
704 static void build_protos(struct proto prot[TLS_NUM_CONFIG][TLS_NUM_CONFIG],
705 			 struct proto *base)
706 {
707 	prot[TLS_BASE][TLS_BASE] = *base;
708 	prot[TLS_BASE][TLS_BASE].setsockopt	= tls_setsockopt;
709 	prot[TLS_BASE][TLS_BASE].getsockopt	= tls_getsockopt;
710 	prot[TLS_BASE][TLS_BASE].close		= tls_sk_proto_close;
711 
712 	prot[TLS_SW][TLS_BASE] = prot[TLS_BASE][TLS_BASE];
713 	prot[TLS_SW][TLS_BASE].sendmsg		= tls_sw_sendmsg;
714 	prot[TLS_SW][TLS_BASE].sendpage		= tls_sw_sendpage;
715 
716 	prot[TLS_BASE][TLS_SW] = prot[TLS_BASE][TLS_BASE];
717 	prot[TLS_BASE][TLS_SW].recvmsg		  = tls_sw_recvmsg;
718 	prot[TLS_BASE][TLS_SW].stream_memory_read = tls_sw_stream_read;
719 	prot[TLS_BASE][TLS_SW].close		  = tls_sk_proto_close;
720 
721 	prot[TLS_SW][TLS_SW] = prot[TLS_SW][TLS_BASE];
722 	prot[TLS_SW][TLS_SW].recvmsg		= tls_sw_recvmsg;
723 	prot[TLS_SW][TLS_SW].stream_memory_read	= tls_sw_stream_read;
724 	prot[TLS_SW][TLS_SW].close		= tls_sk_proto_close;
725 
726 #ifdef CONFIG_TLS_DEVICE
727 	prot[TLS_HW][TLS_BASE] = prot[TLS_BASE][TLS_BASE];
728 	prot[TLS_HW][TLS_BASE].sendmsg		= tls_device_sendmsg;
729 	prot[TLS_HW][TLS_BASE].sendpage		= tls_device_sendpage;
730 
731 	prot[TLS_HW][TLS_SW] = prot[TLS_BASE][TLS_SW];
732 	prot[TLS_HW][TLS_SW].sendmsg		= tls_device_sendmsg;
733 	prot[TLS_HW][TLS_SW].sendpage		= tls_device_sendpage;
734 
735 	prot[TLS_BASE][TLS_HW] = prot[TLS_BASE][TLS_SW];
736 
737 	prot[TLS_SW][TLS_HW] = prot[TLS_SW][TLS_SW];
738 
739 	prot[TLS_HW][TLS_HW] = prot[TLS_HW][TLS_SW];
740 #endif
741 
742 	prot[TLS_HW_RECORD][TLS_HW_RECORD] = *base;
743 	prot[TLS_HW_RECORD][TLS_HW_RECORD].hash		= tls_hw_hash;
744 	prot[TLS_HW_RECORD][TLS_HW_RECORD].unhash	= tls_hw_unhash;
745 	prot[TLS_HW_RECORD][TLS_HW_RECORD].close	= tls_sk_proto_close;
746 }
747 
748 static int tls_init(struct sock *sk)
749 {
750 	struct tls_context *ctx;
751 	int rc = 0;
752 
753 	if (tls_hw_prot(sk))
754 		goto out;
755 
756 	/* The TLS ulp is currently supported only for TCP sockets
757 	 * in ESTABLISHED state.
758 	 * Supporting sockets in LISTEN state will require us
759 	 * to modify the accept implementation to clone rather then
760 	 * share the ulp context.
761 	 */
762 	if (sk->sk_state != TCP_ESTABLISHED)
763 		return -ENOTSUPP;
764 
765 	/* allocate tls context */
766 	ctx = create_ctx(sk);
767 	if (!ctx) {
768 		rc = -ENOMEM;
769 		goto out;
770 	}
771 
772 	tls_build_proto(sk);
773 	ctx->tx_conf = TLS_BASE;
774 	ctx->rx_conf = TLS_BASE;
775 	update_sk_prot(sk, ctx);
776 out:
777 	return rc;
778 }
779 
780 void tls_register_device(struct tls_device *device)
781 {
782 	spin_lock_bh(&device_spinlock);
783 	list_add_tail(&device->dev_list, &device_list);
784 	spin_unlock_bh(&device_spinlock);
785 }
786 EXPORT_SYMBOL(tls_register_device);
787 
788 void tls_unregister_device(struct tls_device *device)
789 {
790 	spin_lock_bh(&device_spinlock);
791 	list_del(&device->dev_list);
792 	spin_unlock_bh(&device_spinlock);
793 }
794 EXPORT_SYMBOL(tls_unregister_device);
795 
796 static struct tcp_ulp_ops tcp_tls_ulp_ops __read_mostly = {
797 	.name			= "tls",
798 	.owner			= THIS_MODULE,
799 	.init			= tls_init,
800 };
801 
802 static int __init tls_register(void)
803 {
804 	tls_sw_proto_ops = inet_stream_ops;
805 	tls_sw_proto_ops.splice_read = tls_sw_splice_read;
806 
807 #ifdef CONFIG_TLS_DEVICE
808 	tls_device_init();
809 #endif
810 	tcp_register_ulp(&tcp_tls_ulp_ops);
811 
812 	return 0;
813 }
814 
815 static void __exit tls_unregister(void)
816 {
817 	tcp_unregister_ulp(&tcp_tls_ulp_ops);
818 #ifdef CONFIG_TLS_DEVICE
819 	tls_device_cleanup();
820 #endif
821 }
822 
823 module_init(tls_register);
824 module_exit(tls_unregister);
825