xref: /linux/net/tls/tls_main.c (revision 2c63221cd9e5c0dad0424029aeb1c40faada8330)
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 
271 	if (sk)
272 		kfree_rcu(ctx, rcu);
273 	else
274 		kfree(ctx);
275 }
276 
277 static void tls_sk_proto_cleanup(struct sock *sk,
278 				 struct tls_context *ctx, long timeo)
279 {
280 	if (unlikely(sk->sk_write_pending) &&
281 	    !wait_on_pending_writer(sk, &timeo))
282 		tls_handle_open_record(sk, 0);
283 
284 	/* We need these for tls_sw_fallback handling of other packets */
285 	if (ctx->tx_conf == TLS_SW) {
286 		kfree(ctx->tx.rec_seq);
287 		kfree(ctx->tx.iv);
288 		tls_sw_release_resources_tx(sk);
289 		TLS_DEC_STATS(sock_net(sk), LINUX_MIB_TLSCURRTXSW);
290 	} else if (ctx->tx_conf == TLS_HW) {
291 		tls_device_free_resources_tx(sk);
292 		TLS_DEC_STATS(sock_net(sk), LINUX_MIB_TLSCURRTXDEVICE);
293 	}
294 
295 	if (ctx->rx_conf == TLS_SW) {
296 		tls_sw_release_resources_rx(sk);
297 		TLS_DEC_STATS(sock_net(sk), LINUX_MIB_TLSCURRRXSW);
298 	} else if (ctx->rx_conf == TLS_HW) {
299 		tls_device_offload_cleanup_rx(sk);
300 		TLS_DEC_STATS(sock_net(sk), LINUX_MIB_TLSCURRRXDEVICE);
301 	}
302 }
303 
304 static void tls_sk_proto_close(struct sock *sk, long timeout)
305 {
306 	struct inet_connection_sock *icsk = inet_csk(sk);
307 	struct tls_context *ctx = tls_get_ctx(sk);
308 	long timeo = sock_sndtimeo(sk, 0);
309 	bool free_ctx;
310 
311 	if (ctx->tx_conf == TLS_SW)
312 		tls_sw_cancel_work_tx(ctx);
313 
314 	lock_sock(sk);
315 	free_ctx = ctx->tx_conf != TLS_HW && ctx->rx_conf != TLS_HW;
316 
317 	if (ctx->tx_conf != TLS_BASE || ctx->rx_conf != TLS_BASE)
318 		tls_sk_proto_cleanup(sk, ctx, timeo);
319 
320 	write_lock_bh(&sk->sk_callback_lock);
321 	if (free_ctx)
322 		rcu_assign_pointer(icsk->icsk_ulp_data, NULL);
323 	sk->sk_prot = ctx->sk_proto;
324 	if (sk->sk_write_space == tls_write_space)
325 		sk->sk_write_space = ctx->sk_write_space;
326 	write_unlock_bh(&sk->sk_callback_lock);
327 	release_sock(sk);
328 	if (ctx->tx_conf == TLS_SW)
329 		tls_sw_free_ctx_tx(ctx);
330 	if (ctx->rx_conf == TLS_SW || ctx->rx_conf == TLS_HW)
331 		tls_sw_strparser_done(ctx);
332 	if (ctx->rx_conf == TLS_SW)
333 		tls_sw_free_ctx_rx(ctx);
334 	ctx->sk_proto->close(sk, timeout);
335 
336 	if (free_ctx)
337 		tls_ctx_free(sk, ctx);
338 }
339 
340 static int do_tls_getsockopt_tx(struct sock *sk, char __user *optval,
341 				int __user *optlen)
342 {
343 	int rc = 0;
344 	struct tls_context *ctx = tls_get_ctx(sk);
345 	struct tls_crypto_info *crypto_info;
346 	int len;
347 
348 	if (get_user(len, optlen))
349 		return -EFAULT;
350 
351 	if (!optval || (len < sizeof(*crypto_info))) {
352 		rc = -EINVAL;
353 		goto out;
354 	}
355 
356 	if (!ctx) {
357 		rc = -EBUSY;
358 		goto out;
359 	}
360 
361 	/* get user crypto info */
362 	crypto_info = &ctx->crypto_send.info;
363 
364 	if (!TLS_CRYPTO_INFO_READY(crypto_info)) {
365 		rc = -EBUSY;
366 		goto out;
367 	}
368 
369 	if (len == sizeof(*crypto_info)) {
370 		if (copy_to_user(optval, crypto_info, sizeof(*crypto_info)))
371 			rc = -EFAULT;
372 		goto out;
373 	}
374 
375 	switch (crypto_info->cipher_type) {
376 	case TLS_CIPHER_AES_GCM_128: {
377 		struct tls12_crypto_info_aes_gcm_128 *
378 		  crypto_info_aes_gcm_128 =
379 		  container_of(crypto_info,
380 			       struct tls12_crypto_info_aes_gcm_128,
381 			       info);
382 
383 		if (len != sizeof(*crypto_info_aes_gcm_128)) {
384 			rc = -EINVAL;
385 			goto out;
386 		}
387 		lock_sock(sk);
388 		memcpy(crypto_info_aes_gcm_128->iv,
389 		       ctx->tx.iv + TLS_CIPHER_AES_GCM_128_SALT_SIZE,
390 		       TLS_CIPHER_AES_GCM_128_IV_SIZE);
391 		memcpy(crypto_info_aes_gcm_128->rec_seq, ctx->tx.rec_seq,
392 		       TLS_CIPHER_AES_GCM_128_REC_SEQ_SIZE);
393 		release_sock(sk);
394 		if (copy_to_user(optval,
395 				 crypto_info_aes_gcm_128,
396 				 sizeof(*crypto_info_aes_gcm_128)))
397 			rc = -EFAULT;
398 		break;
399 	}
400 	case TLS_CIPHER_AES_GCM_256: {
401 		struct tls12_crypto_info_aes_gcm_256 *
402 		  crypto_info_aes_gcm_256 =
403 		  container_of(crypto_info,
404 			       struct tls12_crypto_info_aes_gcm_256,
405 			       info);
406 
407 		if (len != sizeof(*crypto_info_aes_gcm_256)) {
408 			rc = -EINVAL;
409 			goto out;
410 		}
411 		lock_sock(sk);
412 		memcpy(crypto_info_aes_gcm_256->iv,
413 		       ctx->tx.iv + TLS_CIPHER_AES_GCM_256_SALT_SIZE,
414 		       TLS_CIPHER_AES_GCM_256_IV_SIZE);
415 		memcpy(crypto_info_aes_gcm_256->rec_seq, ctx->tx.rec_seq,
416 		       TLS_CIPHER_AES_GCM_256_REC_SEQ_SIZE);
417 		release_sock(sk);
418 		if (copy_to_user(optval,
419 				 crypto_info_aes_gcm_256,
420 				 sizeof(*crypto_info_aes_gcm_256)))
421 			rc = -EFAULT;
422 		break;
423 	}
424 	default:
425 		rc = -EINVAL;
426 	}
427 
428 out:
429 	return rc;
430 }
431 
432 static int do_tls_getsockopt(struct sock *sk, int optname,
433 			     char __user *optval, int __user *optlen)
434 {
435 	int rc = 0;
436 
437 	switch (optname) {
438 	case TLS_TX:
439 		rc = do_tls_getsockopt_tx(sk, optval, optlen);
440 		break;
441 	default:
442 		rc = -ENOPROTOOPT;
443 		break;
444 	}
445 	return rc;
446 }
447 
448 static int tls_getsockopt(struct sock *sk, int level, int optname,
449 			  char __user *optval, int __user *optlen)
450 {
451 	struct tls_context *ctx = tls_get_ctx(sk);
452 
453 	if (level != SOL_TLS)
454 		return ctx->sk_proto->getsockopt(sk, level,
455 						 optname, optval, optlen);
456 
457 	return do_tls_getsockopt(sk, optname, optval, optlen);
458 }
459 
460 static int do_tls_setsockopt_conf(struct sock *sk, char __user *optval,
461 				  unsigned int optlen, int tx)
462 {
463 	struct tls_crypto_info *crypto_info;
464 	struct tls_crypto_info *alt_crypto_info;
465 	struct tls_context *ctx = tls_get_ctx(sk);
466 	size_t optsize;
467 	int rc = 0;
468 	int conf;
469 
470 	if (!optval || (optlen < sizeof(*crypto_info))) {
471 		rc = -EINVAL;
472 		goto out;
473 	}
474 
475 	if (tx) {
476 		crypto_info = &ctx->crypto_send.info;
477 		alt_crypto_info = &ctx->crypto_recv.info;
478 	} else {
479 		crypto_info = &ctx->crypto_recv.info;
480 		alt_crypto_info = &ctx->crypto_send.info;
481 	}
482 
483 	/* Currently we don't support set crypto info more than one time */
484 	if (TLS_CRYPTO_INFO_READY(crypto_info)) {
485 		rc = -EBUSY;
486 		goto out;
487 	}
488 
489 	rc = copy_from_user(crypto_info, optval, sizeof(*crypto_info));
490 	if (rc) {
491 		rc = -EFAULT;
492 		goto err_crypto_info;
493 	}
494 
495 	/* check version */
496 	if (crypto_info->version != TLS_1_2_VERSION &&
497 	    crypto_info->version != TLS_1_3_VERSION) {
498 		rc = -ENOTSUPP;
499 		goto err_crypto_info;
500 	}
501 
502 	/* Ensure that TLS version and ciphers are same in both directions */
503 	if (TLS_CRYPTO_INFO_READY(alt_crypto_info)) {
504 		if (alt_crypto_info->version != crypto_info->version ||
505 		    alt_crypto_info->cipher_type != crypto_info->cipher_type) {
506 			rc = -EINVAL;
507 			goto err_crypto_info;
508 		}
509 	}
510 
511 	switch (crypto_info->cipher_type) {
512 	case TLS_CIPHER_AES_GCM_128:
513 		optsize = sizeof(struct tls12_crypto_info_aes_gcm_128);
514 		break;
515 	case TLS_CIPHER_AES_GCM_256: {
516 		optsize = sizeof(struct tls12_crypto_info_aes_gcm_256);
517 		break;
518 	}
519 	case TLS_CIPHER_AES_CCM_128:
520 		optsize = sizeof(struct tls12_crypto_info_aes_ccm_128);
521 		break;
522 	default:
523 		rc = -EINVAL;
524 		goto err_crypto_info;
525 	}
526 
527 	if (optlen != optsize) {
528 		rc = -EINVAL;
529 		goto err_crypto_info;
530 	}
531 
532 	rc = copy_from_user(crypto_info + 1, optval + sizeof(*crypto_info),
533 			    optlen - sizeof(*crypto_info));
534 	if (rc) {
535 		rc = -EFAULT;
536 		goto err_crypto_info;
537 	}
538 
539 	if (tx) {
540 		rc = tls_set_device_offload(sk, ctx);
541 		conf = TLS_HW;
542 		if (!rc) {
543 			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSTXDEVICE);
544 			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSCURRTXDEVICE);
545 		} else {
546 			rc = tls_set_sw_offload(sk, ctx, 1);
547 			if (rc)
548 				goto err_crypto_info;
549 			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSTXSW);
550 			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSCURRTXSW);
551 			conf = TLS_SW;
552 		}
553 	} else {
554 		rc = tls_set_device_offload_rx(sk, ctx);
555 		conf = TLS_HW;
556 		if (!rc) {
557 			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSRXDEVICE);
558 			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSCURRRXDEVICE);
559 		} else {
560 			rc = tls_set_sw_offload(sk, ctx, 0);
561 			if (rc)
562 				goto err_crypto_info;
563 			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSRXSW);
564 			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSCURRRXSW);
565 			conf = TLS_SW;
566 		}
567 		tls_sw_strparser_arm(sk, ctx);
568 	}
569 
570 	if (tx)
571 		ctx->tx_conf = conf;
572 	else
573 		ctx->rx_conf = conf;
574 	update_sk_prot(sk, ctx);
575 	if (tx) {
576 		ctx->sk_write_space = sk->sk_write_space;
577 		sk->sk_write_space = tls_write_space;
578 	} else {
579 		sk->sk_socket->ops = &tls_sw_proto_ops;
580 	}
581 	goto out;
582 
583 err_crypto_info:
584 	memzero_explicit(crypto_info, sizeof(union tls_crypto_context));
585 out:
586 	return rc;
587 }
588 
589 static int do_tls_setsockopt(struct sock *sk, int optname,
590 			     char __user *optval, unsigned int optlen)
591 {
592 	int rc = 0;
593 
594 	switch (optname) {
595 	case TLS_TX:
596 	case TLS_RX:
597 		lock_sock(sk);
598 		rc = do_tls_setsockopt_conf(sk, optval, optlen,
599 					    optname == TLS_TX);
600 		release_sock(sk);
601 		break;
602 	default:
603 		rc = -ENOPROTOOPT;
604 		break;
605 	}
606 	return rc;
607 }
608 
609 static int tls_setsockopt(struct sock *sk, int level, int optname,
610 			  char __user *optval, unsigned int optlen)
611 {
612 	struct tls_context *ctx = tls_get_ctx(sk);
613 
614 	if (level != SOL_TLS)
615 		return ctx->sk_proto->setsockopt(sk, level, optname, optval,
616 						 optlen);
617 
618 	return do_tls_setsockopt(sk, optname, optval, optlen);
619 }
620 
621 struct tls_context *tls_ctx_create(struct sock *sk)
622 {
623 	struct inet_connection_sock *icsk = inet_csk(sk);
624 	struct tls_context *ctx;
625 
626 	ctx = kzalloc(sizeof(*ctx), GFP_ATOMIC);
627 	if (!ctx)
628 		return NULL;
629 
630 	rcu_assign_pointer(icsk->icsk_ulp_data, ctx);
631 	ctx->sk_proto = sk->sk_prot;
632 	return ctx;
633 }
634 
635 static void tls_build_proto(struct sock *sk)
636 {
637 	int ip_ver = sk->sk_family == AF_INET6 ? TLSV6 : TLSV4;
638 
639 	/* Build IPv6 TLS whenever the address of tcpv6 _prot changes */
640 	if (ip_ver == TLSV6 &&
641 	    unlikely(sk->sk_prot != smp_load_acquire(&saved_tcpv6_prot))) {
642 		mutex_lock(&tcpv6_prot_mutex);
643 		if (likely(sk->sk_prot != saved_tcpv6_prot)) {
644 			build_protos(tls_prots[TLSV6], sk->sk_prot);
645 			smp_store_release(&saved_tcpv6_prot, sk->sk_prot);
646 		}
647 		mutex_unlock(&tcpv6_prot_mutex);
648 	}
649 
650 	if (ip_ver == TLSV4 &&
651 	    unlikely(sk->sk_prot != smp_load_acquire(&saved_tcpv4_prot))) {
652 		mutex_lock(&tcpv4_prot_mutex);
653 		if (likely(sk->sk_prot != saved_tcpv4_prot)) {
654 			build_protos(tls_prots[TLSV4], sk->sk_prot);
655 			smp_store_release(&saved_tcpv4_prot, sk->sk_prot);
656 		}
657 		mutex_unlock(&tcpv4_prot_mutex);
658 	}
659 }
660 
661 static void build_protos(struct proto prot[TLS_NUM_CONFIG][TLS_NUM_CONFIG],
662 			 struct proto *base)
663 {
664 	prot[TLS_BASE][TLS_BASE] = *base;
665 	prot[TLS_BASE][TLS_BASE].setsockopt	= tls_setsockopt;
666 	prot[TLS_BASE][TLS_BASE].getsockopt	= tls_getsockopt;
667 	prot[TLS_BASE][TLS_BASE].close		= tls_sk_proto_close;
668 
669 	prot[TLS_SW][TLS_BASE] = prot[TLS_BASE][TLS_BASE];
670 	prot[TLS_SW][TLS_BASE].sendmsg		= tls_sw_sendmsg;
671 	prot[TLS_SW][TLS_BASE].sendpage		= tls_sw_sendpage;
672 
673 	prot[TLS_BASE][TLS_SW] = prot[TLS_BASE][TLS_BASE];
674 	prot[TLS_BASE][TLS_SW].recvmsg		  = tls_sw_recvmsg;
675 	prot[TLS_BASE][TLS_SW].stream_memory_read = tls_sw_stream_read;
676 	prot[TLS_BASE][TLS_SW].close		  = tls_sk_proto_close;
677 
678 	prot[TLS_SW][TLS_SW] = prot[TLS_SW][TLS_BASE];
679 	prot[TLS_SW][TLS_SW].recvmsg		= tls_sw_recvmsg;
680 	prot[TLS_SW][TLS_SW].stream_memory_read	= tls_sw_stream_read;
681 	prot[TLS_SW][TLS_SW].close		= tls_sk_proto_close;
682 
683 #ifdef CONFIG_TLS_DEVICE
684 	prot[TLS_HW][TLS_BASE] = prot[TLS_BASE][TLS_BASE];
685 	prot[TLS_HW][TLS_BASE].sendmsg		= tls_device_sendmsg;
686 	prot[TLS_HW][TLS_BASE].sendpage		= tls_device_sendpage;
687 
688 	prot[TLS_HW][TLS_SW] = prot[TLS_BASE][TLS_SW];
689 	prot[TLS_HW][TLS_SW].sendmsg		= tls_device_sendmsg;
690 	prot[TLS_HW][TLS_SW].sendpage		= tls_device_sendpage;
691 
692 	prot[TLS_BASE][TLS_HW] = prot[TLS_BASE][TLS_SW];
693 
694 	prot[TLS_SW][TLS_HW] = prot[TLS_SW][TLS_SW];
695 
696 	prot[TLS_HW][TLS_HW] = prot[TLS_HW][TLS_SW];
697 #endif
698 #ifdef CONFIG_TLS_TOE
699 	prot[TLS_HW_RECORD][TLS_HW_RECORD] = *base;
700 	prot[TLS_HW_RECORD][TLS_HW_RECORD].hash		= tls_toe_hash;
701 	prot[TLS_HW_RECORD][TLS_HW_RECORD].unhash	= tls_toe_unhash;
702 #endif
703 }
704 
705 static int tls_init(struct sock *sk)
706 {
707 	struct tls_context *ctx;
708 	int rc = 0;
709 
710 	tls_build_proto(sk);
711 
712 #ifdef CONFIG_TLS_TOE
713 	if (tls_toe_bypass(sk))
714 		return 0;
715 #endif
716 
717 	/* The TLS ulp is currently supported only for TCP sockets
718 	 * in ESTABLISHED state.
719 	 * Supporting sockets in LISTEN state will require us
720 	 * to modify the accept implementation to clone rather then
721 	 * share the ulp context.
722 	 */
723 	if (sk->sk_state != TCP_ESTABLISHED)
724 		return -ENOTSUPP;
725 
726 	/* allocate tls context */
727 	write_lock_bh(&sk->sk_callback_lock);
728 	ctx = tls_ctx_create(sk);
729 	if (!ctx) {
730 		rc = -ENOMEM;
731 		goto out;
732 	}
733 
734 	ctx->tx_conf = TLS_BASE;
735 	ctx->rx_conf = TLS_BASE;
736 	update_sk_prot(sk, ctx);
737 out:
738 	write_unlock_bh(&sk->sk_callback_lock);
739 	return rc;
740 }
741 
742 static void tls_update(struct sock *sk, struct proto *p)
743 {
744 	struct tls_context *ctx;
745 
746 	ctx = tls_get_ctx(sk);
747 	if (likely(ctx))
748 		ctx->sk_proto = p;
749 	else
750 		sk->sk_prot = p;
751 }
752 
753 static int tls_get_info(const struct sock *sk, struct sk_buff *skb)
754 {
755 	u16 version, cipher_type;
756 	struct tls_context *ctx;
757 	struct nlattr *start;
758 	int err;
759 
760 	start = nla_nest_start_noflag(skb, INET_ULP_INFO_TLS);
761 	if (!start)
762 		return -EMSGSIZE;
763 
764 	rcu_read_lock();
765 	ctx = rcu_dereference(inet_csk(sk)->icsk_ulp_data);
766 	if (!ctx) {
767 		err = 0;
768 		goto nla_failure;
769 	}
770 	version = ctx->prot_info.version;
771 	if (version) {
772 		err = nla_put_u16(skb, TLS_INFO_VERSION, version);
773 		if (err)
774 			goto nla_failure;
775 	}
776 	cipher_type = ctx->prot_info.cipher_type;
777 	if (cipher_type) {
778 		err = nla_put_u16(skb, TLS_INFO_CIPHER, cipher_type);
779 		if (err)
780 			goto nla_failure;
781 	}
782 	err = nla_put_u16(skb, TLS_INFO_TXCONF, tls_user_config(ctx, true));
783 	if (err)
784 		goto nla_failure;
785 
786 	err = nla_put_u16(skb, TLS_INFO_RXCONF, tls_user_config(ctx, false));
787 	if (err)
788 		goto nla_failure;
789 
790 	rcu_read_unlock();
791 	nla_nest_end(skb, start);
792 	return 0;
793 
794 nla_failure:
795 	rcu_read_unlock();
796 	nla_nest_cancel(skb, start);
797 	return err;
798 }
799 
800 static size_t tls_get_info_size(const struct sock *sk)
801 {
802 	size_t size = 0;
803 
804 	size += nla_total_size(0) +		/* INET_ULP_INFO_TLS */
805 		nla_total_size(sizeof(u16)) +	/* TLS_INFO_VERSION */
806 		nla_total_size(sizeof(u16)) +	/* TLS_INFO_CIPHER */
807 		nla_total_size(sizeof(u16)) +	/* TLS_INFO_RXCONF */
808 		nla_total_size(sizeof(u16)) +	/* TLS_INFO_TXCONF */
809 		0;
810 
811 	return size;
812 }
813 
814 static int __net_init tls_init_net(struct net *net)
815 {
816 	int err;
817 
818 	net->mib.tls_statistics = alloc_percpu(struct linux_tls_mib);
819 	if (!net->mib.tls_statistics)
820 		return -ENOMEM;
821 
822 	err = tls_proc_init(net);
823 	if (err)
824 		goto err_free_stats;
825 
826 	return 0;
827 err_free_stats:
828 	free_percpu(net->mib.tls_statistics);
829 	return err;
830 }
831 
832 static void __net_exit tls_exit_net(struct net *net)
833 {
834 	tls_proc_fini(net);
835 	free_percpu(net->mib.tls_statistics);
836 }
837 
838 static struct pernet_operations tls_proc_ops = {
839 	.init = tls_init_net,
840 	.exit = tls_exit_net,
841 };
842 
843 static struct tcp_ulp_ops tcp_tls_ulp_ops __read_mostly = {
844 	.name			= "tls",
845 	.owner			= THIS_MODULE,
846 	.init			= tls_init,
847 	.update			= tls_update,
848 	.get_info		= tls_get_info,
849 	.get_info_size		= tls_get_info_size,
850 };
851 
852 static int __init tls_register(void)
853 {
854 	int err;
855 
856 	err = register_pernet_subsys(&tls_proc_ops);
857 	if (err)
858 		return err;
859 
860 	tls_sw_proto_ops = inet_stream_ops;
861 	tls_sw_proto_ops.splice_read = tls_sw_splice_read;
862 
863 	tls_device_init();
864 	tcp_register_ulp(&tcp_tls_ulp_ops);
865 
866 	return 0;
867 }
868 
869 static void __exit tls_unregister(void)
870 {
871 	tcp_unregister_ulp(&tcp_tls_ulp_ops);
872 	tls_device_cleanup();
873 	unregister_pernet_subsys(&tls_proc_ops);
874 }
875 
876 module_init(tls_register);
877 module_exit(tls_unregister);
878