xref: /linux/net/tls/tls_main.c (revision 79b6bb73f888933cbcd20b0ef3976cde67951b72)
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 #include <linux/inet_diag.h>
43 
44 #include <net/snmp.h>
45 #include <net/tls.h>
46 #include <net/tls_toe.h>
47 
48 MODULE_AUTHOR("Mellanox Technologies");
49 MODULE_DESCRIPTION("Transport Layer Security Support");
50 MODULE_LICENSE("Dual BSD/GPL");
51 MODULE_ALIAS_TCP_ULP("tls");
52 
53 enum {
54 	TLSV4,
55 	TLSV6,
56 	TLS_NUM_PROTS,
57 };
58 
59 static struct proto *saved_tcpv6_prot;
60 static DEFINE_MUTEX(tcpv6_prot_mutex);
61 static struct proto *saved_tcpv4_prot;
62 static DEFINE_MUTEX(tcpv4_prot_mutex);
63 static struct proto tls_prots[TLS_NUM_PROTS][TLS_NUM_CONFIG][TLS_NUM_CONFIG];
64 static struct proto_ops tls_sw_proto_ops;
65 static void build_protos(struct proto prot[TLS_NUM_CONFIG][TLS_NUM_CONFIG],
66 			 struct proto *base);
67 
68 void update_sk_prot(struct sock *sk, struct tls_context *ctx)
69 {
70 	int ip_ver = sk->sk_family == AF_INET6 ? TLSV6 : TLSV4;
71 
72 	sk->sk_prot = &tls_prots[ip_ver][ctx->tx_conf][ctx->rx_conf];
73 }
74 
75 int wait_on_pending_writer(struct sock *sk, long *timeo)
76 {
77 	int rc = 0;
78 	DEFINE_WAIT_FUNC(wait, woken_wake_function);
79 
80 	add_wait_queue(sk_sleep(sk), &wait);
81 	while (1) {
82 		if (!*timeo) {
83 			rc = -EAGAIN;
84 			break;
85 		}
86 
87 		if (signal_pending(current)) {
88 			rc = sock_intr_errno(*timeo);
89 			break;
90 		}
91 
92 		if (sk_wait_event(sk, timeo, !sk->sk_write_pending, &wait))
93 			break;
94 	}
95 	remove_wait_queue(sk_sleep(sk), &wait);
96 	return rc;
97 }
98 
99 int tls_push_sg(struct sock *sk,
100 		struct tls_context *ctx,
101 		struct scatterlist *sg,
102 		u16 first_offset,
103 		int flags)
104 {
105 	int sendpage_flags = flags | MSG_SENDPAGE_NOTLAST;
106 	int ret = 0;
107 	struct page *p;
108 	size_t size;
109 	int offset = first_offset;
110 
111 	size = sg->length - offset;
112 	offset += sg->offset;
113 
114 	ctx->in_tcp_sendpages = true;
115 	while (1) {
116 		if (sg_is_last(sg))
117 			sendpage_flags = flags;
118 
119 		/* is sending application-limited? */
120 		tcp_rate_check_app_limited(sk);
121 		p = sg_page(sg);
122 retry:
123 		ret = do_tcp_sendpages(sk, p, offset, size, sendpage_flags);
124 
125 		if (ret != size) {
126 			if (ret > 0) {
127 				offset += ret;
128 				size -= ret;
129 				goto retry;
130 			}
131 
132 			offset -= sg->offset;
133 			ctx->partially_sent_offset = offset;
134 			ctx->partially_sent_record = (void *)sg;
135 			ctx->in_tcp_sendpages = false;
136 			return ret;
137 		}
138 
139 		put_page(p);
140 		sk_mem_uncharge(sk, sg->length);
141 		sg = sg_next(sg);
142 		if (!sg)
143 			break;
144 
145 		offset = sg->offset;
146 		size = sg->length;
147 	}
148 
149 	ctx->in_tcp_sendpages = false;
150 
151 	return 0;
152 }
153 
154 static int tls_handle_open_record(struct sock *sk, int flags)
155 {
156 	struct tls_context *ctx = tls_get_ctx(sk);
157 
158 	if (tls_is_pending_open_record(ctx))
159 		return ctx->push_pending_record(sk, flags);
160 
161 	return 0;
162 }
163 
164 int tls_proccess_cmsg(struct sock *sk, struct msghdr *msg,
165 		      unsigned char *record_type)
166 {
167 	struct cmsghdr *cmsg;
168 	int rc = -EINVAL;
169 
170 	for_each_cmsghdr(cmsg, msg) {
171 		if (!CMSG_OK(msg, cmsg))
172 			return -EINVAL;
173 		if (cmsg->cmsg_level != SOL_TLS)
174 			continue;
175 
176 		switch (cmsg->cmsg_type) {
177 		case TLS_SET_RECORD_TYPE:
178 			if (cmsg->cmsg_len < CMSG_LEN(sizeof(*record_type)))
179 				return -EINVAL;
180 
181 			if (msg->msg_flags & MSG_MORE)
182 				return -EINVAL;
183 
184 			rc = tls_handle_open_record(sk, msg->msg_flags);
185 			if (rc)
186 				return rc;
187 
188 			*record_type = *(unsigned char *)CMSG_DATA(cmsg);
189 			rc = 0;
190 			break;
191 		default:
192 			return -EINVAL;
193 		}
194 	}
195 
196 	return rc;
197 }
198 
199 int tls_push_partial_record(struct sock *sk, struct tls_context *ctx,
200 			    int flags)
201 {
202 	struct scatterlist *sg;
203 	u16 offset;
204 
205 	sg = ctx->partially_sent_record;
206 	offset = ctx->partially_sent_offset;
207 
208 	ctx->partially_sent_record = NULL;
209 	return tls_push_sg(sk, ctx, sg, offset, flags);
210 }
211 
212 bool tls_free_partial_record(struct sock *sk, struct tls_context *ctx)
213 {
214 	struct scatterlist *sg;
215 
216 	sg = ctx->partially_sent_record;
217 	if (!sg)
218 		return false;
219 
220 	while (1) {
221 		put_page(sg_page(sg));
222 		sk_mem_uncharge(sk, sg->length);
223 
224 		if (sg_is_last(sg))
225 			break;
226 		sg++;
227 	}
228 	ctx->partially_sent_record = NULL;
229 	return true;
230 }
231 
232 static void tls_write_space(struct sock *sk)
233 {
234 	struct tls_context *ctx = tls_get_ctx(sk);
235 
236 	/* If in_tcp_sendpages call lower protocol write space handler
237 	 * to ensure we wake up any waiting operations there. For example
238 	 * if do_tcp_sendpages where to call sk_wait_event.
239 	 */
240 	if (ctx->in_tcp_sendpages) {
241 		ctx->sk_write_space(sk);
242 		return;
243 	}
244 
245 #ifdef CONFIG_TLS_DEVICE
246 	if (ctx->tx_conf == TLS_HW)
247 		tls_device_write_space(sk, ctx);
248 	else
249 #endif
250 		tls_sw_write_space(sk, ctx);
251 
252 	ctx->sk_write_space(sk);
253 }
254 
255 /**
256  * tls_ctx_free() - free TLS ULP context
257  * @sk:  socket to with @ctx is attached
258  * @ctx: TLS context structure
259  *
260  * Free TLS context. If @sk is %NULL caller guarantees that the socket
261  * to which @ctx was attached has no outstanding references.
262  */
263 void tls_ctx_free(struct sock *sk, struct tls_context *ctx)
264 {
265 	if (!ctx)
266 		return;
267 
268 	memzero_explicit(&ctx->crypto_send, sizeof(ctx->crypto_send));
269 	memzero_explicit(&ctx->crypto_recv, sizeof(ctx->crypto_recv));
270 	mutex_destroy(&ctx->tx_lock);
271 
272 	if (sk)
273 		kfree_rcu(ctx, rcu);
274 	else
275 		kfree(ctx);
276 }
277 
278 static void tls_sk_proto_cleanup(struct sock *sk,
279 				 struct tls_context *ctx, long timeo)
280 {
281 	if (unlikely(sk->sk_write_pending) &&
282 	    !wait_on_pending_writer(sk, &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_release_resources_tx(sk);
290 		TLS_DEC_STATS(sock_net(sk), LINUX_MIB_TLSCURRTXSW);
291 	} else if (ctx->tx_conf == TLS_HW) {
292 		tls_device_free_resources_tx(sk);
293 		TLS_DEC_STATS(sock_net(sk), LINUX_MIB_TLSCURRTXDEVICE);
294 	}
295 
296 	if (ctx->rx_conf == TLS_SW) {
297 		tls_sw_release_resources_rx(sk);
298 		TLS_DEC_STATS(sock_net(sk), LINUX_MIB_TLSCURRRXSW);
299 	} else if (ctx->rx_conf == TLS_HW) {
300 		tls_device_offload_cleanup_rx(sk);
301 		TLS_DEC_STATS(sock_net(sk), LINUX_MIB_TLSCURRRXDEVICE);
302 	}
303 }
304 
305 static void tls_sk_proto_close(struct sock *sk, long timeout)
306 {
307 	struct inet_connection_sock *icsk = inet_csk(sk);
308 	struct tls_context *ctx = tls_get_ctx(sk);
309 	long timeo = sock_sndtimeo(sk, 0);
310 	bool free_ctx;
311 
312 	if (ctx->tx_conf == TLS_SW)
313 		tls_sw_cancel_work_tx(ctx);
314 
315 	lock_sock(sk);
316 	free_ctx = ctx->tx_conf != TLS_HW && ctx->rx_conf != TLS_HW;
317 
318 	if (ctx->tx_conf != TLS_BASE || ctx->rx_conf != TLS_BASE)
319 		tls_sk_proto_cleanup(sk, ctx, timeo);
320 
321 	write_lock_bh(&sk->sk_callback_lock);
322 	if (free_ctx)
323 		rcu_assign_pointer(icsk->icsk_ulp_data, NULL);
324 	sk->sk_prot = ctx->sk_proto;
325 	if (sk->sk_write_space == tls_write_space)
326 		sk->sk_write_space = ctx->sk_write_space;
327 	write_unlock_bh(&sk->sk_callback_lock);
328 	release_sock(sk);
329 	if (ctx->tx_conf == TLS_SW)
330 		tls_sw_free_ctx_tx(ctx);
331 	if (ctx->rx_conf == TLS_SW || ctx->rx_conf == TLS_HW)
332 		tls_sw_strparser_done(ctx);
333 	if (ctx->rx_conf == TLS_SW)
334 		tls_sw_free_ctx_rx(ctx);
335 	ctx->sk_proto->close(sk, timeout);
336 
337 	if (free_ctx)
338 		tls_ctx_free(sk, ctx);
339 }
340 
341 static int do_tls_getsockopt_tx(struct sock *sk, char __user *optval,
342 				int __user *optlen)
343 {
344 	int rc = 0;
345 	struct tls_context *ctx = tls_get_ctx(sk);
346 	struct tls_crypto_info *crypto_info;
347 	int len;
348 
349 	if (get_user(len, optlen))
350 		return -EFAULT;
351 
352 	if (!optval || (len < sizeof(*crypto_info))) {
353 		rc = -EINVAL;
354 		goto out;
355 	}
356 
357 	if (!ctx) {
358 		rc = -EBUSY;
359 		goto out;
360 	}
361 
362 	/* get user crypto info */
363 	crypto_info = &ctx->crypto_send.info;
364 
365 	if (!TLS_CRYPTO_INFO_READY(crypto_info)) {
366 		rc = -EBUSY;
367 		goto out;
368 	}
369 
370 	if (len == sizeof(*crypto_info)) {
371 		if (copy_to_user(optval, crypto_info, sizeof(*crypto_info)))
372 			rc = -EFAULT;
373 		goto out;
374 	}
375 
376 	switch (crypto_info->cipher_type) {
377 	case TLS_CIPHER_AES_GCM_128: {
378 		struct tls12_crypto_info_aes_gcm_128 *
379 		  crypto_info_aes_gcm_128 =
380 		  container_of(crypto_info,
381 			       struct tls12_crypto_info_aes_gcm_128,
382 			       info);
383 
384 		if (len != sizeof(*crypto_info_aes_gcm_128)) {
385 			rc = -EINVAL;
386 			goto out;
387 		}
388 		lock_sock(sk);
389 		memcpy(crypto_info_aes_gcm_128->iv,
390 		       ctx->tx.iv + TLS_CIPHER_AES_GCM_128_SALT_SIZE,
391 		       TLS_CIPHER_AES_GCM_128_IV_SIZE);
392 		memcpy(crypto_info_aes_gcm_128->rec_seq, ctx->tx.rec_seq,
393 		       TLS_CIPHER_AES_GCM_128_REC_SEQ_SIZE);
394 		release_sock(sk);
395 		if (copy_to_user(optval,
396 				 crypto_info_aes_gcm_128,
397 				 sizeof(*crypto_info_aes_gcm_128)))
398 			rc = -EFAULT;
399 		break;
400 	}
401 	case TLS_CIPHER_AES_GCM_256: {
402 		struct tls12_crypto_info_aes_gcm_256 *
403 		  crypto_info_aes_gcm_256 =
404 		  container_of(crypto_info,
405 			       struct tls12_crypto_info_aes_gcm_256,
406 			       info);
407 
408 		if (len != sizeof(*crypto_info_aes_gcm_256)) {
409 			rc = -EINVAL;
410 			goto out;
411 		}
412 		lock_sock(sk);
413 		memcpy(crypto_info_aes_gcm_256->iv,
414 		       ctx->tx.iv + TLS_CIPHER_AES_GCM_256_SALT_SIZE,
415 		       TLS_CIPHER_AES_GCM_256_IV_SIZE);
416 		memcpy(crypto_info_aes_gcm_256->rec_seq, ctx->tx.rec_seq,
417 		       TLS_CIPHER_AES_GCM_256_REC_SEQ_SIZE);
418 		release_sock(sk);
419 		if (copy_to_user(optval,
420 				 crypto_info_aes_gcm_256,
421 				 sizeof(*crypto_info_aes_gcm_256)))
422 			rc = -EFAULT;
423 		break;
424 	}
425 	default:
426 		rc = -EINVAL;
427 	}
428 
429 out:
430 	return rc;
431 }
432 
433 static int do_tls_getsockopt(struct sock *sk, int optname,
434 			     char __user *optval, int __user *optlen)
435 {
436 	int rc = 0;
437 
438 	switch (optname) {
439 	case TLS_TX:
440 		rc = do_tls_getsockopt_tx(sk, optval, optlen);
441 		break;
442 	default:
443 		rc = -ENOPROTOOPT;
444 		break;
445 	}
446 	return rc;
447 }
448 
449 static int tls_getsockopt(struct sock *sk, int level, int optname,
450 			  char __user *optval, int __user *optlen)
451 {
452 	struct tls_context *ctx = tls_get_ctx(sk);
453 
454 	if (level != SOL_TLS)
455 		return ctx->sk_proto->getsockopt(sk, level,
456 						 optname, optval, optlen);
457 
458 	return do_tls_getsockopt(sk, optname, optval, optlen);
459 }
460 
461 static int do_tls_setsockopt_conf(struct sock *sk, char __user *optval,
462 				  unsigned int optlen, int tx)
463 {
464 	struct tls_crypto_info *crypto_info;
465 	struct tls_crypto_info *alt_crypto_info;
466 	struct tls_context *ctx = tls_get_ctx(sk);
467 	size_t optsize;
468 	int rc = 0;
469 	int conf;
470 
471 	if (!optval || (optlen < sizeof(*crypto_info))) {
472 		rc = -EINVAL;
473 		goto out;
474 	}
475 
476 	if (tx) {
477 		crypto_info = &ctx->crypto_send.info;
478 		alt_crypto_info = &ctx->crypto_recv.info;
479 	} else {
480 		crypto_info = &ctx->crypto_recv.info;
481 		alt_crypto_info = &ctx->crypto_send.info;
482 	}
483 
484 	/* Currently we don't support set crypto info more than one time */
485 	if (TLS_CRYPTO_INFO_READY(crypto_info)) {
486 		rc = -EBUSY;
487 		goto out;
488 	}
489 
490 	rc = copy_from_user(crypto_info, optval, sizeof(*crypto_info));
491 	if (rc) {
492 		rc = -EFAULT;
493 		goto err_crypto_info;
494 	}
495 
496 	/* check version */
497 	if (crypto_info->version != TLS_1_2_VERSION &&
498 	    crypto_info->version != TLS_1_3_VERSION) {
499 		rc = -ENOTSUPP;
500 		goto err_crypto_info;
501 	}
502 
503 	/* Ensure that TLS version and ciphers are same in both directions */
504 	if (TLS_CRYPTO_INFO_READY(alt_crypto_info)) {
505 		if (alt_crypto_info->version != crypto_info->version ||
506 		    alt_crypto_info->cipher_type != crypto_info->cipher_type) {
507 			rc = -EINVAL;
508 			goto err_crypto_info;
509 		}
510 	}
511 
512 	switch (crypto_info->cipher_type) {
513 	case TLS_CIPHER_AES_GCM_128:
514 		optsize = sizeof(struct tls12_crypto_info_aes_gcm_128);
515 		break;
516 	case TLS_CIPHER_AES_GCM_256: {
517 		optsize = sizeof(struct tls12_crypto_info_aes_gcm_256);
518 		break;
519 	}
520 	case TLS_CIPHER_AES_CCM_128:
521 		optsize = sizeof(struct tls12_crypto_info_aes_ccm_128);
522 		break;
523 	default:
524 		rc = -EINVAL;
525 		goto err_crypto_info;
526 	}
527 
528 	if (optlen != optsize) {
529 		rc = -EINVAL;
530 		goto err_crypto_info;
531 	}
532 
533 	rc = copy_from_user(crypto_info + 1, optval + sizeof(*crypto_info),
534 			    optlen - sizeof(*crypto_info));
535 	if (rc) {
536 		rc = -EFAULT;
537 		goto err_crypto_info;
538 	}
539 
540 	if (tx) {
541 		rc = tls_set_device_offload(sk, ctx);
542 		conf = TLS_HW;
543 		if (!rc) {
544 			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSTXDEVICE);
545 			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSCURRTXDEVICE);
546 		} else {
547 			rc = tls_set_sw_offload(sk, ctx, 1);
548 			if (rc)
549 				goto err_crypto_info;
550 			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSTXSW);
551 			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSCURRTXSW);
552 			conf = TLS_SW;
553 		}
554 	} else {
555 		rc = tls_set_device_offload_rx(sk, ctx);
556 		conf = TLS_HW;
557 		if (!rc) {
558 			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSRXDEVICE);
559 			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSCURRRXDEVICE);
560 		} else {
561 			rc = tls_set_sw_offload(sk, ctx, 0);
562 			if (rc)
563 				goto err_crypto_info;
564 			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSRXSW);
565 			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSCURRRXSW);
566 			conf = TLS_SW;
567 		}
568 		tls_sw_strparser_arm(sk, ctx);
569 	}
570 
571 	if (tx)
572 		ctx->tx_conf = conf;
573 	else
574 		ctx->rx_conf = conf;
575 	update_sk_prot(sk, ctx);
576 	if (tx) {
577 		ctx->sk_write_space = sk->sk_write_space;
578 		sk->sk_write_space = tls_write_space;
579 	} else {
580 		sk->sk_socket->ops = &tls_sw_proto_ops;
581 	}
582 	goto out;
583 
584 err_crypto_info:
585 	memzero_explicit(crypto_info, sizeof(union tls_crypto_context));
586 out:
587 	return rc;
588 }
589 
590 static int do_tls_setsockopt(struct sock *sk, int optname,
591 			     char __user *optval, unsigned int optlen)
592 {
593 	int rc = 0;
594 
595 	switch (optname) {
596 	case TLS_TX:
597 	case TLS_RX:
598 		lock_sock(sk);
599 		rc = do_tls_setsockopt_conf(sk, optval, optlen,
600 					    optname == TLS_TX);
601 		release_sock(sk);
602 		break;
603 	default:
604 		rc = -ENOPROTOOPT;
605 		break;
606 	}
607 	return rc;
608 }
609 
610 static int tls_setsockopt(struct sock *sk, int level, int optname,
611 			  char __user *optval, unsigned int optlen)
612 {
613 	struct tls_context *ctx = tls_get_ctx(sk);
614 
615 	if (level != SOL_TLS)
616 		return ctx->sk_proto->setsockopt(sk, level, optname, optval,
617 						 optlen);
618 
619 	return do_tls_setsockopt(sk, optname, optval, optlen);
620 }
621 
622 struct tls_context *tls_ctx_create(struct sock *sk)
623 {
624 	struct inet_connection_sock *icsk = inet_csk(sk);
625 	struct tls_context *ctx;
626 
627 	ctx = kzalloc(sizeof(*ctx), GFP_ATOMIC);
628 	if (!ctx)
629 		return NULL;
630 
631 	mutex_init(&ctx->tx_lock);
632 	rcu_assign_pointer(icsk->icsk_ulp_data, ctx);
633 	ctx->sk_proto = sk->sk_prot;
634 	return ctx;
635 }
636 
637 static void tls_build_proto(struct sock *sk)
638 {
639 	int ip_ver = sk->sk_family == AF_INET6 ? TLSV6 : TLSV4;
640 
641 	/* Build IPv6 TLS whenever the address of tcpv6 _prot changes */
642 	if (ip_ver == TLSV6 &&
643 	    unlikely(sk->sk_prot != smp_load_acquire(&saved_tcpv6_prot))) {
644 		mutex_lock(&tcpv6_prot_mutex);
645 		if (likely(sk->sk_prot != saved_tcpv6_prot)) {
646 			build_protos(tls_prots[TLSV6], sk->sk_prot);
647 			smp_store_release(&saved_tcpv6_prot, sk->sk_prot);
648 		}
649 		mutex_unlock(&tcpv6_prot_mutex);
650 	}
651 
652 	if (ip_ver == TLSV4 &&
653 	    unlikely(sk->sk_prot != smp_load_acquire(&saved_tcpv4_prot))) {
654 		mutex_lock(&tcpv4_prot_mutex);
655 		if (likely(sk->sk_prot != saved_tcpv4_prot)) {
656 			build_protos(tls_prots[TLSV4], sk->sk_prot);
657 			smp_store_release(&saved_tcpv4_prot, sk->sk_prot);
658 		}
659 		mutex_unlock(&tcpv4_prot_mutex);
660 	}
661 }
662 
663 static void build_protos(struct proto prot[TLS_NUM_CONFIG][TLS_NUM_CONFIG],
664 			 struct proto *base)
665 {
666 	prot[TLS_BASE][TLS_BASE] = *base;
667 	prot[TLS_BASE][TLS_BASE].setsockopt	= tls_setsockopt;
668 	prot[TLS_BASE][TLS_BASE].getsockopt	= tls_getsockopt;
669 	prot[TLS_BASE][TLS_BASE].close		= tls_sk_proto_close;
670 
671 	prot[TLS_SW][TLS_BASE] = prot[TLS_BASE][TLS_BASE];
672 	prot[TLS_SW][TLS_BASE].sendmsg		= tls_sw_sendmsg;
673 	prot[TLS_SW][TLS_BASE].sendpage		= tls_sw_sendpage;
674 
675 	prot[TLS_BASE][TLS_SW] = prot[TLS_BASE][TLS_BASE];
676 	prot[TLS_BASE][TLS_SW].recvmsg		  = tls_sw_recvmsg;
677 	prot[TLS_BASE][TLS_SW].stream_memory_read = tls_sw_stream_read;
678 	prot[TLS_BASE][TLS_SW].close		  = tls_sk_proto_close;
679 
680 	prot[TLS_SW][TLS_SW] = prot[TLS_SW][TLS_BASE];
681 	prot[TLS_SW][TLS_SW].recvmsg		= tls_sw_recvmsg;
682 	prot[TLS_SW][TLS_SW].stream_memory_read	= tls_sw_stream_read;
683 	prot[TLS_SW][TLS_SW].close		= tls_sk_proto_close;
684 
685 #ifdef CONFIG_TLS_DEVICE
686 	prot[TLS_HW][TLS_BASE] = prot[TLS_BASE][TLS_BASE];
687 	prot[TLS_HW][TLS_BASE].sendmsg		= tls_device_sendmsg;
688 	prot[TLS_HW][TLS_BASE].sendpage		= tls_device_sendpage;
689 
690 	prot[TLS_HW][TLS_SW] = prot[TLS_BASE][TLS_SW];
691 	prot[TLS_HW][TLS_SW].sendmsg		= tls_device_sendmsg;
692 	prot[TLS_HW][TLS_SW].sendpage		= tls_device_sendpage;
693 
694 	prot[TLS_BASE][TLS_HW] = prot[TLS_BASE][TLS_SW];
695 
696 	prot[TLS_SW][TLS_HW] = prot[TLS_SW][TLS_SW];
697 
698 	prot[TLS_HW][TLS_HW] = prot[TLS_HW][TLS_SW];
699 #endif
700 #ifdef CONFIG_TLS_TOE
701 	prot[TLS_HW_RECORD][TLS_HW_RECORD] = *base;
702 	prot[TLS_HW_RECORD][TLS_HW_RECORD].hash		= tls_toe_hash;
703 	prot[TLS_HW_RECORD][TLS_HW_RECORD].unhash	= tls_toe_unhash;
704 #endif
705 }
706 
707 static int tls_init(struct sock *sk)
708 {
709 	struct tls_context *ctx;
710 	int rc = 0;
711 
712 	tls_build_proto(sk);
713 
714 #ifdef CONFIG_TLS_TOE
715 	if (tls_toe_bypass(sk))
716 		return 0;
717 #endif
718 
719 	/* The TLS ulp is currently supported only for TCP sockets
720 	 * in ESTABLISHED state.
721 	 * Supporting sockets in LISTEN state will require us
722 	 * to modify the accept implementation to clone rather then
723 	 * share the ulp context.
724 	 */
725 	if (sk->sk_state != TCP_ESTABLISHED)
726 		return -ENOTSUPP;
727 
728 	/* allocate tls context */
729 	write_lock_bh(&sk->sk_callback_lock);
730 	ctx = tls_ctx_create(sk);
731 	if (!ctx) {
732 		rc = -ENOMEM;
733 		goto out;
734 	}
735 
736 	ctx->tx_conf = TLS_BASE;
737 	ctx->rx_conf = TLS_BASE;
738 	update_sk_prot(sk, ctx);
739 out:
740 	write_unlock_bh(&sk->sk_callback_lock);
741 	return rc;
742 }
743 
744 static void tls_update(struct sock *sk, struct proto *p)
745 {
746 	struct tls_context *ctx;
747 
748 	ctx = tls_get_ctx(sk);
749 	if (likely(ctx))
750 		ctx->sk_proto = p;
751 	else
752 		sk->sk_prot = p;
753 }
754 
755 static int tls_get_info(const struct sock *sk, struct sk_buff *skb)
756 {
757 	u16 version, cipher_type;
758 	struct tls_context *ctx;
759 	struct nlattr *start;
760 	int err;
761 
762 	start = nla_nest_start_noflag(skb, INET_ULP_INFO_TLS);
763 	if (!start)
764 		return -EMSGSIZE;
765 
766 	rcu_read_lock();
767 	ctx = rcu_dereference(inet_csk(sk)->icsk_ulp_data);
768 	if (!ctx) {
769 		err = 0;
770 		goto nla_failure;
771 	}
772 	version = ctx->prot_info.version;
773 	if (version) {
774 		err = nla_put_u16(skb, TLS_INFO_VERSION, version);
775 		if (err)
776 			goto nla_failure;
777 	}
778 	cipher_type = ctx->prot_info.cipher_type;
779 	if (cipher_type) {
780 		err = nla_put_u16(skb, TLS_INFO_CIPHER, cipher_type);
781 		if (err)
782 			goto nla_failure;
783 	}
784 	err = nla_put_u16(skb, TLS_INFO_TXCONF, tls_user_config(ctx, true));
785 	if (err)
786 		goto nla_failure;
787 
788 	err = nla_put_u16(skb, TLS_INFO_RXCONF, tls_user_config(ctx, false));
789 	if (err)
790 		goto nla_failure;
791 
792 	rcu_read_unlock();
793 	nla_nest_end(skb, start);
794 	return 0;
795 
796 nla_failure:
797 	rcu_read_unlock();
798 	nla_nest_cancel(skb, start);
799 	return err;
800 }
801 
802 static size_t tls_get_info_size(const struct sock *sk)
803 {
804 	size_t size = 0;
805 
806 	size += nla_total_size(0) +		/* INET_ULP_INFO_TLS */
807 		nla_total_size(sizeof(u16)) +	/* TLS_INFO_VERSION */
808 		nla_total_size(sizeof(u16)) +	/* TLS_INFO_CIPHER */
809 		nla_total_size(sizeof(u16)) +	/* TLS_INFO_RXCONF */
810 		nla_total_size(sizeof(u16)) +	/* TLS_INFO_TXCONF */
811 		0;
812 
813 	return size;
814 }
815 
816 static int __net_init tls_init_net(struct net *net)
817 {
818 	int err;
819 
820 	net->mib.tls_statistics = alloc_percpu(struct linux_tls_mib);
821 	if (!net->mib.tls_statistics)
822 		return -ENOMEM;
823 
824 	err = tls_proc_init(net);
825 	if (err)
826 		goto err_free_stats;
827 
828 	return 0;
829 err_free_stats:
830 	free_percpu(net->mib.tls_statistics);
831 	return err;
832 }
833 
834 static void __net_exit tls_exit_net(struct net *net)
835 {
836 	tls_proc_fini(net);
837 	free_percpu(net->mib.tls_statistics);
838 }
839 
840 static struct pernet_operations tls_proc_ops = {
841 	.init = tls_init_net,
842 	.exit = tls_exit_net,
843 };
844 
845 static struct tcp_ulp_ops tcp_tls_ulp_ops __read_mostly = {
846 	.name			= "tls",
847 	.owner			= THIS_MODULE,
848 	.init			= tls_init,
849 	.update			= tls_update,
850 	.get_info		= tls_get_info,
851 	.get_info_size		= tls_get_info_size,
852 };
853 
854 static int __init tls_register(void)
855 {
856 	int err;
857 
858 	err = register_pernet_subsys(&tls_proc_ops);
859 	if (err)
860 		return err;
861 
862 	tls_sw_proto_ops = inet_stream_ops;
863 	tls_sw_proto_ops.splice_read = tls_sw_splice_read;
864 	tls_sw_proto_ops.sendpage_locked   = tls_sw_sendpage_locked,
865 
866 	tls_device_init();
867 	tcp_register_ulp(&tcp_tls_ulp_ops);
868 
869 	return 0;
870 }
871 
872 static void __exit tls_unregister(void)
873 {
874 	tcp_unregister_ulp(&tcp_tls_ulp_ops);
875 	tls_device_cleanup();
876 	unregister_pernet_subsys(&tls_proc_ops);
877 }
878 
879 module_init(tls_register);
880 module_exit(tls_unregister);
881