xref: /openbmc/linux/net/tls/tls_main.c (revision fbb6b31a)
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 const struct proto *saved_tcpv6_prot;
60 static DEFINE_MUTEX(tcpv6_prot_mutex);
61 static const 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_proto_ops[TLS_NUM_PROTS][TLS_NUM_CONFIG][TLS_NUM_CONFIG];
65 static void build_protos(struct proto prot[TLS_NUM_CONFIG][TLS_NUM_CONFIG],
66 			 const 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 	WRITE_ONCE(sk->sk_prot,
73 		   &tls_prots[ip_ver][ctx->tx_conf][ctx->rx_conf]);
74 	WRITE_ONCE(sk->sk_socket->ops,
75 		   &tls_proto_ops[ip_ver][ctx->tx_conf][ctx->rx_conf]);
76 }
77 
78 int wait_on_pending_writer(struct sock *sk, long *timeo)
79 {
80 	int rc = 0;
81 	DEFINE_WAIT_FUNC(wait, woken_wake_function);
82 
83 	add_wait_queue(sk_sleep(sk), &wait);
84 	while (1) {
85 		if (!*timeo) {
86 			rc = -EAGAIN;
87 			break;
88 		}
89 
90 		if (signal_pending(current)) {
91 			rc = sock_intr_errno(*timeo);
92 			break;
93 		}
94 
95 		if (sk_wait_event(sk, timeo, !sk->sk_write_pending, &wait))
96 			break;
97 	}
98 	remove_wait_queue(sk_sleep(sk), &wait);
99 	return rc;
100 }
101 
102 int tls_push_sg(struct sock *sk,
103 		struct tls_context *ctx,
104 		struct scatterlist *sg,
105 		u16 first_offset,
106 		int flags)
107 {
108 	int sendpage_flags = flags | MSG_SENDPAGE_NOTLAST;
109 	int ret = 0;
110 	struct page *p;
111 	size_t size;
112 	int offset = first_offset;
113 
114 	size = sg->length - offset;
115 	offset += sg->offset;
116 
117 	ctx->in_tcp_sendpages = true;
118 	while (1) {
119 		if (sg_is_last(sg))
120 			sendpage_flags = flags;
121 
122 		/* is sending application-limited? */
123 		tcp_rate_check_app_limited(sk);
124 		p = sg_page(sg);
125 retry:
126 		ret = do_tcp_sendpages(sk, p, offset, size, sendpage_flags);
127 
128 		if (ret != size) {
129 			if (ret > 0) {
130 				offset += ret;
131 				size -= ret;
132 				goto retry;
133 			}
134 
135 			offset -= sg->offset;
136 			ctx->partially_sent_offset = offset;
137 			ctx->partially_sent_record = (void *)sg;
138 			ctx->in_tcp_sendpages = false;
139 			return ret;
140 		}
141 
142 		put_page(p);
143 		sk_mem_uncharge(sk, sg->length);
144 		sg = sg_next(sg);
145 		if (!sg)
146 			break;
147 
148 		offset = sg->offset;
149 		size = sg->length;
150 	}
151 
152 	ctx->in_tcp_sendpages = false;
153 
154 	return 0;
155 }
156 
157 static int tls_handle_open_record(struct sock *sk, int flags)
158 {
159 	struct tls_context *ctx = tls_get_ctx(sk);
160 
161 	if (tls_is_pending_open_record(ctx))
162 		return ctx->push_pending_record(sk, flags);
163 
164 	return 0;
165 }
166 
167 int tls_proccess_cmsg(struct sock *sk, struct msghdr *msg,
168 		      unsigned char *record_type)
169 {
170 	struct cmsghdr *cmsg;
171 	int rc = -EINVAL;
172 
173 	for_each_cmsghdr(cmsg, msg) {
174 		if (!CMSG_OK(msg, cmsg))
175 			return -EINVAL;
176 		if (cmsg->cmsg_level != SOL_TLS)
177 			continue;
178 
179 		switch (cmsg->cmsg_type) {
180 		case TLS_SET_RECORD_TYPE:
181 			if (cmsg->cmsg_len < CMSG_LEN(sizeof(*record_type)))
182 				return -EINVAL;
183 
184 			if (msg->msg_flags & MSG_MORE)
185 				return -EINVAL;
186 
187 			rc = tls_handle_open_record(sk, msg->msg_flags);
188 			if (rc)
189 				return rc;
190 
191 			*record_type = *(unsigned char *)CMSG_DATA(cmsg);
192 			rc = 0;
193 			break;
194 		default:
195 			return -EINVAL;
196 		}
197 	}
198 
199 	return rc;
200 }
201 
202 int tls_push_partial_record(struct sock *sk, struct tls_context *ctx,
203 			    int flags)
204 {
205 	struct scatterlist *sg;
206 	u16 offset;
207 
208 	sg = ctx->partially_sent_record;
209 	offset = ctx->partially_sent_offset;
210 
211 	ctx->partially_sent_record = NULL;
212 	return tls_push_sg(sk, ctx, sg, offset, flags);
213 }
214 
215 void tls_free_partial_record(struct sock *sk, struct tls_context *ctx)
216 {
217 	struct scatterlist *sg;
218 
219 	for (sg = ctx->partially_sent_record; sg; sg = sg_next(sg)) {
220 		put_page(sg_page(sg));
221 		sk_mem_uncharge(sk, sg->length);
222 	}
223 	ctx->partially_sent_record = NULL;
224 }
225 
226 static void tls_write_space(struct sock *sk)
227 {
228 	struct tls_context *ctx = tls_get_ctx(sk);
229 
230 	/* If in_tcp_sendpages call lower protocol write space handler
231 	 * to ensure we wake up any waiting operations there. For example
232 	 * if do_tcp_sendpages where to call sk_wait_event.
233 	 */
234 	if (ctx->in_tcp_sendpages) {
235 		ctx->sk_write_space(sk);
236 		return;
237 	}
238 
239 #ifdef CONFIG_TLS_DEVICE
240 	if (ctx->tx_conf == TLS_HW)
241 		tls_device_write_space(sk, ctx);
242 	else
243 #endif
244 		tls_sw_write_space(sk, ctx);
245 
246 	ctx->sk_write_space(sk);
247 }
248 
249 /**
250  * tls_ctx_free() - free TLS ULP context
251  * @sk:  socket to with @ctx is attached
252  * @ctx: TLS context structure
253  *
254  * Free TLS context. If @sk is %NULL caller guarantees that the socket
255  * to which @ctx was attached has no outstanding references.
256  */
257 void tls_ctx_free(struct sock *sk, struct tls_context *ctx)
258 {
259 	if (!ctx)
260 		return;
261 
262 	memzero_explicit(&ctx->crypto_send, sizeof(ctx->crypto_send));
263 	memzero_explicit(&ctx->crypto_recv, sizeof(ctx->crypto_recv));
264 	mutex_destroy(&ctx->tx_lock);
265 
266 	if (sk)
267 		kfree_rcu(ctx, rcu);
268 	else
269 		kfree(ctx);
270 }
271 
272 static void tls_sk_proto_cleanup(struct sock *sk,
273 				 struct tls_context *ctx, long timeo)
274 {
275 	if (unlikely(sk->sk_write_pending) &&
276 	    !wait_on_pending_writer(sk, &timeo))
277 		tls_handle_open_record(sk, 0);
278 
279 	/* We need these for tls_sw_fallback handling of other packets */
280 	if (ctx->tx_conf == TLS_SW) {
281 		kfree(ctx->tx.rec_seq);
282 		kfree(ctx->tx.iv);
283 		tls_sw_release_resources_tx(sk);
284 		TLS_DEC_STATS(sock_net(sk), LINUX_MIB_TLSCURRTXSW);
285 	} else if (ctx->tx_conf == TLS_HW) {
286 		tls_device_free_resources_tx(sk);
287 		TLS_DEC_STATS(sock_net(sk), LINUX_MIB_TLSCURRTXDEVICE);
288 	}
289 
290 	if (ctx->rx_conf == TLS_SW) {
291 		tls_sw_release_resources_rx(sk);
292 		TLS_DEC_STATS(sock_net(sk), LINUX_MIB_TLSCURRRXSW);
293 	} else if (ctx->rx_conf == TLS_HW) {
294 		tls_device_offload_cleanup_rx(sk);
295 		TLS_DEC_STATS(sock_net(sk), LINUX_MIB_TLSCURRRXDEVICE);
296 	}
297 }
298 
299 static void tls_sk_proto_close(struct sock *sk, long timeout)
300 {
301 	struct inet_connection_sock *icsk = inet_csk(sk);
302 	struct tls_context *ctx = tls_get_ctx(sk);
303 	long timeo = sock_sndtimeo(sk, 0);
304 	bool free_ctx;
305 
306 	if (ctx->tx_conf == TLS_SW)
307 		tls_sw_cancel_work_tx(ctx);
308 
309 	lock_sock(sk);
310 	free_ctx = ctx->tx_conf != TLS_HW && ctx->rx_conf != TLS_HW;
311 
312 	if (ctx->tx_conf != TLS_BASE || ctx->rx_conf != TLS_BASE)
313 		tls_sk_proto_cleanup(sk, ctx, timeo);
314 
315 	write_lock_bh(&sk->sk_callback_lock);
316 	if (free_ctx)
317 		rcu_assign_pointer(icsk->icsk_ulp_data, NULL);
318 	WRITE_ONCE(sk->sk_prot, ctx->sk_proto);
319 	if (sk->sk_write_space == tls_write_space)
320 		sk->sk_write_space = ctx->sk_write_space;
321 	write_unlock_bh(&sk->sk_callback_lock);
322 	release_sock(sk);
323 	if (ctx->tx_conf == TLS_SW)
324 		tls_sw_free_ctx_tx(ctx);
325 	if (ctx->rx_conf == TLS_SW || ctx->rx_conf == TLS_HW)
326 		tls_sw_strparser_done(ctx);
327 	if (ctx->rx_conf == TLS_SW)
328 		tls_sw_free_ctx_rx(ctx);
329 	ctx->sk_proto->close(sk, timeout);
330 
331 	if (free_ctx)
332 		tls_ctx_free(sk, ctx);
333 }
334 
335 static int do_tls_getsockopt_conf(struct sock *sk, char __user *optval,
336 				  int __user *optlen, int tx)
337 {
338 	int rc = 0;
339 	struct tls_context *ctx = tls_get_ctx(sk);
340 	struct tls_crypto_info *crypto_info;
341 	struct cipher_context *cctx;
342 	int len;
343 
344 	if (get_user(len, optlen))
345 		return -EFAULT;
346 
347 	if (!optval || (len < sizeof(*crypto_info))) {
348 		rc = -EINVAL;
349 		goto out;
350 	}
351 
352 	if (!ctx) {
353 		rc = -EBUSY;
354 		goto out;
355 	}
356 
357 	/* get user crypto info */
358 	if (tx) {
359 		crypto_info = &ctx->crypto_send.info;
360 		cctx = &ctx->tx;
361 	} else {
362 		crypto_info = &ctx->crypto_recv.info;
363 		cctx = &ctx->rx;
364 	}
365 
366 	if (!TLS_CRYPTO_INFO_READY(crypto_info)) {
367 		rc = -EBUSY;
368 		goto out;
369 	}
370 
371 	if (len == sizeof(*crypto_info)) {
372 		if (copy_to_user(optval, crypto_info, sizeof(*crypto_info)))
373 			rc = -EFAULT;
374 		goto out;
375 	}
376 
377 	switch (crypto_info->cipher_type) {
378 	case TLS_CIPHER_AES_GCM_128: {
379 		struct tls12_crypto_info_aes_gcm_128 *
380 		  crypto_info_aes_gcm_128 =
381 		  container_of(crypto_info,
382 			       struct tls12_crypto_info_aes_gcm_128,
383 			       info);
384 
385 		if (len != sizeof(*crypto_info_aes_gcm_128)) {
386 			rc = -EINVAL;
387 			goto out;
388 		}
389 		lock_sock(sk);
390 		memcpy(crypto_info_aes_gcm_128->iv,
391 		       cctx->iv + TLS_CIPHER_AES_GCM_128_SALT_SIZE,
392 		       TLS_CIPHER_AES_GCM_128_IV_SIZE);
393 		memcpy(crypto_info_aes_gcm_128->rec_seq, cctx->rec_seq,
394 		       TLS_CIPHER_AES_GCM_128_REC_SEQ_SIZE);
395 		release_sock(sk);
396 		if (copy_to_user(optval,
397 				 crypto_info_aes_gcm_128,
398 				 sizeof(*crypto_info_aes_gcm_128)))
399 			rc = -EFAULT;
400 		break;
401 	}
402 	case TLS_CIPHER_AES_GCM_256: {
403 		struct tls12_crypto_info_aes_gcm_256 *
404 		  crypto_info_aes_gcm_256 =
405 		  container_of(crypto_info,
406 			       struct tls12_crypto_info_aes_gcm_256,
407 			       info);
408 
409 		if (len != sizeof(*crypto_info_aes_gcm_256)) {
410 			rc = -EINVAL;
411 			goto out;
412 		}
413 		lock_sock(sk);
414 		memcpy(crypto_info_aes_gcm_256->iv,
415 		       cctx->iv + TLS_CIPHER_AES_GCM_256_SALT_SIZE,
416 		       TLS_CIPHER_AES_GCM_256_IV_SIZE);
417 		memcpy(crypto_info_aes_gcm_256->rec_seq, cctx->rec_seq,
418 		       TLS_CIPHER_AES_GCM_256_REC_SEQ_SIZE);
419 		release_sock(sk);
420 		if (copy_to_user(optval,
421 				 crypto_info_aes_gcm_256,
422 				 sizeof(*crypto_info_aes_gcm_256)))
423 			rc = -EFAULT;
424 		break;
425 	}
426 	case TLS_CIPHER_AES_CCM_128: {
427 		struct tls12_crypto_info_aes_ccm_128 *aes_ccm_128 =
428 			container_of(crypto_info,
429 				struct tls12_crypto_info_aes_ccm_128, info);
430 
431 		if (len != sizeof(*aes_ccm_128)) {
432 			rc = -EINVAL;
433 			goto out;
434 		}
435 		lock_sock(sk);
436 		memcpy(aes_ccm_128->iv,
437 		       cctx->iv + TLS_CIPHER_AES_CCM_128_SALT_SIZE,
438 		       TLS_CIPHER_AES_CCM_128_IV_SIZE);
439 		memcpy(aes_ccm_128->rec_seq, cctx->rec_seq,
440 		       TLS_CIPHER_AES_CCM_128_REC_SEQ_SIZE);
441 		release_sock(sk);
442 		if (copy_to_user(optval, aes_ccm_128, sizeof(*aes_ccm_128)))
443 			rc = -EFAULT;
444 		break;
445 	}
446 	case TLS_CIPHER_CHACHA20_POLY1305: {
447 		struct tls12_crypto_info_chacha20_poly1305 *chacha20_poly1305 =
448 			container_of(crypto_info,
449 				struct tls12_crypto_info_chacha20_poly1305,
450 				info);
451 
452 		if (len != sizeof(*chacha20_poly1305)) {
453 			rc = -EINVAL;
454 			goto out;
455 		}
456 		lock_sock(sk);
457 		memcpy(chacha20_poly1305->iv,
458 		       cctx->iv + TLS_CIPHER_CHACHA20_POLY1305_SALT_SIZE,
459 		       TLS_CIPHER_CHACHA20_POLY1305_IV_SIZE);
460 		memcpy(chacha20_poly1305->rec_seq, cctx->rec_seq,
461 		       TLS_CIPHER_CHACHA20_POLY1305_REC_SEQ_SIZE);
462 		release_sock(sk);
463 		if (copy_to_user(optval, chacha20_poly1305,
464 				sizeof(*chacha20_poly1305)))
465 			rc = -EFAULT;
466 		break;
467 	}
468 	case TLS_CIPHER_SM4_GCM: {
469 		struct tls12_crypto_info_sm4_gcm *sm4_gcm_info =
470 			container_of(crypto_info,
471 				struct tls12_crypto_info_sm4_gcm, info);
472 
473 		if (len != sizeof(*sm4_gcm_info)) {
474 			rc = -EINVAL;
475 			goto out;
476 		}
477 		lock_sock(sk);
478 		memcpy(sm4_gcm_info->iv,
479 		       cctx->iv + TLS_CIPHER_SM4_GCM_SALT_SIZE,
480 		       TLS_CIPHER_SM4_GCM_IV_SIZE);
481 		memcpy(sm4_gcm_info->rec_seq, cctx->rec_seq,
482 		       TLS_CIPHER_SM4_GCM_REC_SEQ_SIZE);
483 		release_sock(sk);
484 		if (copy_to_user(optval, sm4_gcm_info, sizeof(*sm4_gcm_info)))
485 			rc = -EFAULT;
486 		break;
487 	}
488 	case TLS_CIPHER_SM4_CCM: {
489 		struct tls12_crypto_info_sm4_ccm *sm4_ccm_info =
490 			container_of(crypto_info,
491 				struct tls12_crypto_info_sm4_ccm, info);
492 
493 		if (len != sizeof(*sm4_ccm_info)) {
494 			rc = -EINVAL;
495 			goto out;
496 		}
497 		lock_sock(sk);
498 		memcpy(sm4_ccm_info->iv,
499 		       cctx->iv + TLS_CIPHER_SM4_CCM_SALT_SIZE,
500 		       TLS_CIPHER_SM4_CCM_IV_SIZE);
501 		memcpy(sm4_ccm_info->rec_seq, cctx->rec_seq,
502 		       TLS_CIPHER_SM4_CCM_REC_SEQ_SIZE);
503 		release_sock(sk);
504 		if (copy_to_user(optval, sm4_ccm_info, sizeof(*sm4_ccm_info)))
505 			rc = -EFAULT;
506 		break;
507 	}
508 	default:
509 		rc = -EINVAL;
510 	}
511 
512 out:
513 	return rc;
514 }
515 
516 static int do_tls_getsockopt(struct sock *sk, int optname,
517 			     char __user *optval, int __user *optlen)
518 {
519 	int rc = 0;
520 
521 	switch (optname) {
522 	case TLS_TX:
523 	case TLS_RX:
524 		rc = do_tls_getsockopt_conf(sk, optval, optlen,
525 					    optname == TLS_TX);
526 		break;
527 	default:
528 		rc = -ENOPROTOOPT;
529 		break;
530 	}
531 	return rc;
532 }
533 
534 static int tls_getsockopt(struct sock *sk, int level, int optname,
535 			  char __user *optval, int __user *optlen)
536 {
537 	struct tls_context *ctx = tls_get_ctx(sk);
538 
539 	if (level != SOL_TLS)
540 		return ctx->sk_proto->getsockopt(sk, level,
541 						 optname, optval, optlen);
542 
543 	return do_tls_getsockopt(sk, optname, optval, optlen);
544 }
545 
546 static int do_tls_setsockopt_conf(struct sock *sk, sockptr_t optval,
547 				  unsigned int optlen, int tx)
548 {
549 	struct tls_crypto_info *crypto_info;
550 	struct tls_crypto_info *alt_crypto_info;
551 	struct tls_context *ctx = tls_get_ctx(sk);
552 	size_t optsize;
553 	int rc = 0;
554 	int conf;
555 
556 	if (sockptr_is_null(optval) || (optlen < sizeof(*crypto_info)))
557 		return -EINVAL;
558 
559 	if (tx) {
560 		crypto_info = &ctx->crypto_send.info;
561 		alt_crypto_info = &ctx->crypto_recv.info;
562 	} else {
563 		crypto_info = &ctx->crypto_recv.info;
564 		alt_crypto_info = &ctx->crypto_send.info;
565 	}
566 
567 	/* Currently we don't support set crypto info more than one time */
568 	if (TLS_CRYPTO_INFO_READY(crypto_info))
569 		return -EBUSY;
570 
571 	rc = copy_from_sockptr(crypto_info, optval, sizeof(*crypto_info));
572 	if (rc) {
573 		rc = -EFAULT;
574 		goto err_crypto_info;
575 	}
576 
577 	/* check version */
578 	if (crypto_info->version != TLS_1_2_VERSION &&
579 	    crypto_info->version != TLS_1_3_VERSION) {
580 		rc = -EINVAL;
581 		goto err_crypto_info;
582 	}
583 
584 	/* Ensure that TLS version and ciphers are same in both directions */
585 	if (TLS_CRYPTO_INFO_READY(alt_crypto_info)) {
586 		if (alt_crypto_info->version != crypto_info->version ||
587 		    alt_crypto_info->cipher_type != crypto_info->cipher_type) {
588 			rc = -EINVAL;
589 			goto err_crypto_info;
590 		}
591 	}
592 
593 	switch (crypto_info->cipher_type) {
594 	case TLS_CIPHER_AES_GCM_128:
595 		optsize = sizeof(struct tls12_crypto_info_aes_gcm_128);
596 		break;
597 	case TLS_CIPHER_AES_GCM_256: {
598 		optsize = sizeof(struct tls12_crypto_info_aes_gcm_256);
599 		break;
600 	}
601 	case TLS_CIPHER_AES_CCM_128:
602 		optsize = sizeof(struct tls12_crypto_info_aes_ccm_128);
603 		break;
604 	case TLS_CIPHER_CHACHA20_POLY1305:
605 		optsize = sizeof(struct tls12_crypto_info_chacha20_poly1305);
606 		break;
607 	case TLS_CIPHER_SM4_GCM:
608 		optsize = sizeof(struct tls12_crypto_info_sm4_gcm);
609 		break;
610 	case TLS_CIPHER_SM4_CCM:
611 		optsize = sizeof(struct tls12_crypto_info_sm4_ccm);
612 		break;
613 	default:
614 		rc = -EINVAL;
615 		goto err_crypto_info;
616 	}
617 
618 	if (optlen != optsize) {
619 		rc = -EINVAL;
620 		goto err_crypto_info;
621 	}
622 
623 	rc = copy_from_sockptr_offset(crypto_info + 1, optval,
624 				      sizeof(*crypto_info),
625 				      optlen - sizeof(*crypto_info));
626 	if (rc) {
627 		rc = -EFAULT;
628 		goto err_crypto_info;
629 	}
630 
631 	if (tx) {
632 		rc = tls_set_device_offload(sk, ctx);
633 		conf = TLS_HW;
634 		if (!rc) {
635 			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSTXDEVICE);
636 			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSCURRTXDEVICE);
637 		} else {
638 			rc = tls_set_sw_offload(sk, ctx, 1);
639 			if (rc)
640 				goto err_crypto_info;
641 			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSTXSW);
642 			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSCURRTXSW);
643 			conf = TLS_SW;
644 		}
645 	} else {
646 		rc = tls_set_device_offload_rx(sk, ctx);
647 		conf = TLS_HW;
648 		if (!rc) {
649 			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSRXDEVICE);
650 			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSCURRRXDEVICE);
651 		} else {
652 			rc = tls_set_sw_offload(sk, ctx, 0);
653 			if (rc)
654 				goto err_crypto_info;
655 			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSRXSW);
656 			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSCURRRXSW);
657 			conf = TLS_SW;
658 		}
659 		tls_sw_strparser_arm(sk, ctx);
660 	}
661 
662 	if (tx)
663 		ctx->tx_conf = conf;
664 	else
665 		ctx->rx_conf = conf;
666 	update_sk_prot(sk, ctx);
667 	if (tx) {
668 		ctx->sk_write_space = sk->sk_write_space;
669 		sk->sk_write_space = tls_write_space;
670 	}
671 	return 0;
672 
673 err_crypto_info:
674 	memzero_explicit(crypto_info, sizeof(union tls_crypto_context));
675 	return rc;
676 }
677 
678 static int do_tls_setsockopt(struct sock *sk, int optname, sockptr_t optval,
679 			     unsigned int optlen)
680 {
681 	int rc = 0;
682 
683 	switch (optname) {
684 	case TLS_TX:
685 	case TLS_RX:
686 		lock_sock(sk);
687 		rc = do_tls_setsockopt_conf(sk, optval, optlen,
688 					    optname == TLS_TX);
689 		release_sock(sk);
690 		break;
691 	default:
692 		rc = -ENOPROTOOPT;
693 		break;
694 	}
695 	return rc;
696 }
697 
698 static int tls_setsockopt(struct sock *sk, int level, int optname,
699 			  sockptr_t optval, unsigned int optlen)
700 {
701 	struct tls_context *ctx = tls_get_ctx(sk);
702 
703 	if (level != SOL_TLS)
704 		return ctx->sk_proto->setsockopt(sk, level, optname, optval,
705 						 optlen);
706 
707 	return do_tls_setsockopt(sk, optname, optval, optlen);
708 }
709 
710 struct tls_context *tls_ctx_create(struct sock *sk)
711 {
712 	struct inet_connection_sock *icsk = inet_csk(sk);
713 	struct tls_context *ctx;
714 
715 	ctx = kzalloc(sizeof(*ctx), GFP_ATOMIC);
716 	if (!ctx)
717 		return NULL;
718 
719 	mutex_init(&ctx->tx_lock);
720 	rcu_assign_pointer(icsk->icsk_ulp_data, ctx);
721 	ctx->sk_proto = READ_ONCE(sk->sk_prot);
722 	ctx->sk = sk;
723 	return ctx;
724 }
725 
726 static void build_proto_ops(struct proto_ops ops[TLS_NUM_CONFIG][TLS_NUM_CONFIG],
727 			    const struct proto_ops *base)
728 {
729 	ops[TLS_BASE][TLS_BASE] = *base;
730 
731 	ops[TLS_SW  ][TLS_BASE] = ops[TLS_BASE][TLS_BASE];
732 	ops[TLS_SW  ][TLS_BASE].sendpage_locked	= tls_sw_sendpage_locked;
733 
734 	ops[TLS_BASE][TLS_SW  ] = ops[TLS_BASE][TLS_BASE];
735 	ops[TLS_BASE][TLS_SW  ].splice_read	= tls_sw_splice_read;
736 
737 	ops[TLS_SW  ][TLS_SW  ] = ops[TLS_SW  ][TLS_BASE];
738 	ops[TLS_SW  ][TLS_SW  ].splice_read	= tls_sw_splice_read;
739 
740 #ifdef CONFIG_TLS_DEVICE
741 	ops[TLS_HW  ][TLS_BASE] = ops[TLS_BASE][TLS_BASE];
742 	ops[TLS_HW  ][TLS_BASE].sendpage_locked	= NULL;
743 
744 	ops[TLS_HW  ][TLS_SW  ] = ops[TLS_BASE][TLS_SW  ];
745 	ops[TLS_HW  ][TLS_SW  ].sendpage_locked	= NULL;
746 
747 	ops[TLS_BASE][TLS_HW  ] = ops[TLS_BASE][TLS_SW  ];
748 
749 	ops[TLS_SW  ][TLS_HW  ] = ops[TLS_SW  ][TLS_SW  ];
750 
751 	ops[TLS_HW  ][TLS_HW  ] = ops[TLS_HW  ][TLS_SW  ];
752 	ops[TLS_HW  ][TLS_HW  ].sendpage_locked	= NULL;
753 #endif
754 #ifdef CONFIG_TLS_TOE
755 	ops[TLS_HW_RECORD][TLS_HW_RECORD] = *base;
756 #endif
757 }
758 
759 static void tls_build_proto(struct sock *sk)
760 {
761 	int ip_ver = sk->sk_family == AF_INET6 ? TLSV6 : TLSV4;
762 	struct proto *prot = READ_ONCE(sk->sk_prot);
763 
764 	/* Build IPv6 TLS whenever the address of tcpv6 _prot changes */
765 	if (ip_ver == TLSV6 &&
766 	    unlikely(prot != smp_load_acquire(&saved_tcpv6_prot))) {
767 		mutex_lock(&tcpv6_prot_mutex);
768 		if (likely(prot != saved_tcpv6_prot)) {
769 			build_protos(tls_prots[TLSV6], prot);
770 			build_proto_ops(tls_proto_ops[TLSV6],
771 					sk->sk_socket->ops);
772 			smp_store_release(&saved_tcpv6_prot, prot);
773 		}
774 		mutex_unlock(&tcpv6_prot_mutex);
775 	}
776 
777 	if (ip_ver == TLSV4 &&
778 	    unlikely(prot != smp_load_acquire(&saved_tcpv4_prot))) {
779 		mutex_lock(&tcpv4_prot_mutex);
780 		if (likely(prot != saved_tcpv4_prot)) {
781 			build_protos(tls_prots[TLSV4], prot);
782 			build_proto_ops(tls_proto_ops[TLSV4],
783 					sk->sk_socket->ops);
784 			smp_store_release(&saved_tcpv4_prot, prot);
785 		}
786 		mutex_unlock(&tcpv4_prot_mutex);
787 	}
788 }
789 
790 static void build_protos(struct proto prot[TLS_NUM_CONFIG][TLS_NUM_CONFIG],
791 			 const struct proto *base)
792 {
793 	prot[TLS_BASE][TLS_BASE] = *base;
794 	prot[TLS_BASE][TLS_BASE].setsockopt	= tls_setsockopt;
795 	prot[TLS_BASE][TLS_BASE].getsockopt	= tls_getsockopt;
796 	prot[TLS_BASE][TLS_BASE].close		= tls_sk_proto_close;
797 
798 	prot[TLS_SW][TLS_BASE] = prot[TLS_BASE][TLS_BASE];
799 	prot[TLS_SW][TLS_BASE].sendmsg		= tls_sw_sendmsg;
800 	prot[TLS_SW][TLS_BASE].sendpage		= tls_sw_sendpage;
801 
802 	prot[TLS_BASE][TLS_SW] = prot[TLS_BASE][TLS_BASE];
803 	prot[TLS_BASE][TLS_SW].recvmsg		  = tls_sw_recvmsg;
804 	prot[TLS_BASE][TLS_SW].sock_is_readable   = tls_sw_sock_is_readable;
805 	prot[TLS_BASE][TLS_SW].close		  = tls_sk_proto_close;
806 
807 	prot[TLS_SW][TLS_SW] = prot[TLS_SW][TLS_BASE];
808 	prot[TLS_SW][TLS_SW].recvmsg		= tls_sw_recvmsg;
809 	prot[TLS_SW][TLS_SW].sock_is_readable   = tls_sw_sock_is_readable;
810 	prot[TLS_SW][TLS_SW].close		= tls_sk_proto_close;
811 
812 #ifdef CONFIG_TLS_DEVICE
813 	prot[TLS_HW][TLS_BASE] = prot[TLS_BASE][TLS_BASE];
814 	prot[TLS_HW][TLS_BASE].sendmsg		= tls_device_sendmsg;
815 	prot[TLS_HW][TLS_BASE].sendpage		= tls_device_sendpage;
816 
817 	prot[TLS_HW][TLS_SW] = prot[TLS_BASE][TLS_SW];
818 	prot[TLS_HW][TLS_SW].sendmsg		= tls_device_sendmsg;
819 	prot[TLS_HW][TLS_SW].sendpage		= tls_device_sendpage;
820 
821 	prot[TLS_BASE][TLS_HW] = prot[TLS_BASE][TLS_SW];
822 
823 	prot[TLS_SW][TLS_HW] = prot[TLS_SW][TLS_SW];
824 
825 	prot[TLS_HW][TLS_HW] = prot[TLS_HW][TLS_SW];
826 #endif
827 #ifdef CONFIG_TLS_TOE
828 	prot[TLS_HW_RECORD][TLS_HW_RECORD] = *base;
829 	prot[TLS_HW_RECORD][TLS_HW_RECORD].hash		= tls_toe_hash;
830 	prot[TLS_HW_RECORD][TLS_HW_RECORD].unhash	= tls_toe_unhash;
831 #endif
832 }
833 
834 static int tls_init(struct sock *sk)
835 {
836 	struct tls_context *ctx;
837 	int rc = 0;
838 
839 	tls_build_proto(sk);
840 
841 #ifdef CONFIG_TLS_TOE
842 	if (tls_toe_bypass(sk))
843 		return 0;
844 #endif
845 
846 	/* The TLS ulp is currently supported only for TCP sockets
847 	 * in ESTABLISHED state.
848 	 * Supporting sockets in LISTEN state will require us
849 	 * to modify the accept implementation to clone rather then
850 	 * share the ulp context.
851 	 */
852 	if (sk->sk_state != TCP_ESTABLISHED)
853 		return -ENOTCONN;
854 
855 	/* allocate tls context */
856 	write_lock_bh(&sk->sk_callback_lock);
857 	ctx = tls_ctx_create(sk);
858 	if (!ctx) {
859 		rc = -ENOMEM;
860 		goto out;
861 	}
862 
863 	ctx->tx_conf = TLS_BASE;
864 	ctx->rx_conf = TLS_BASE;
865 	update_sk_prot(sk, ctx);
866 out:
867 	write_unlock_bh(&sk->sk_callback_lock);
868 	return rc;
869 }
870 
871 static void tls_update(struct sock *sk, struct proto *p,
872 		       void (*write_space)(struct sock *sk))
873 {
874 	struct tls_context *ctx;
875 
876 	ctx = tls_get_ctx(sk);
877 	if (likely(ctx)) {
878 		ctx->sk_write_space = write_space;
879 		ctx->sk_proto = p;
880 	} else {
881 		/* Pairs with lockless read in sk_clone_lock(). */
882 		WRITE_ONCE(sk->sk_prot, p);
883 		sk->sk_write_space = write_space;
884 	}
885 }
886 
887 static int tls_get_info(const struct sock *sk, struct sk_buff *skb)
888 {
889 	u16 version, cipher_type;
890 	struct tls_context *ctx;
891 	struct nlattr *start;
892 	int err;
893 
894 	start = nla_nest_start_noflag(skb, INET_ULP_INFO_TLS);
895 	if (!start)
896 		return -EMSGSIZE;
897 
898 	rcu_read_lock();
899 	ctx = rcu_dereference(inet_csk(sk)->icsk_ulp_data);
900 	if (!ctx) {
901 		err = 0;
902 		goto nla_failure;
903 	}
904 	version = ctx->prot_info.version;
905 	if (version) {
906 		err = nla_put_u16(skb, TLS_INFO_VERSION, version);
907 		if (err)
908 			goto nla_failure;
909 	}
910 	cipher_type = ctx->prot_info.cipher_type;
911 	if (cipher_type) {
912 		err = nla_put_u16(skb, TLS_INFO_CIPHER, cipher_type);
913 		if (err)
914 			goto nla_failure;
915 	}
916 	err = nla_put_u16(skb, TLS_INFO_TXCONF, tls_user_config(ctx, true));
917 	if (err)
918 		goto nla_failure;
919 
920 	err = nla_put_u16(skb, TLS_INFO_RXCONF, tls_user_config(ctx, false));
921 	if (err)
922 		goto nla_failure;
923 
924 	rcu_read_unlock();
925 	nla_nest_end(skb, start);
926 	return 0;
927 
928 nla_failure:
929 	rcu_read_unlock();
930 	nla_nest_cancel(skb, start);
931 	return err;
932 }
933 
934 static size_t tls_get_info_size(const struct sock *sk)
935 {
936 	size_t size = 0;
937 
938 	size += nla_total_size(0) +		/* INET_ULP_INFO_TLS */
939 		nla_total_size(sizeof(u16)) +	/* TLS_INFO_VERSION */
940 		nla_total_size(sizeof(u16)) +	/* TLS_INFO_CIPHER */
941 		nla_total_size(sizeof(u16)) +	/* TLS_INFO_RXCONF */
942 		nla_total_size(sizeof(u16)) +	/* TLS_INFO_TXCONF */
943 		0;
944 
945 	return size;
946 }
947 
948 static int __net_init tls_init_net(struct net *net)
949 {
950 	int err;
951 
952 	net->mib.tls_statistics = alloc_percpu(struct linux_tls_mib);
953 	if (!net->mib.tls_statistics)
954 		return -ENOMEM;
955 
956 	err = tls_proc_init(net);
957 	if (err)
958 		goto err_free_stats;
959 
960 	return 0;
961 err_free_stats:
962 	free_percpu(net->mib.tls_statistics);
963 	return err;
964 }
965 
966 static void __net_exit tls_exit_net(struct net *net)
967 {
968 	tls_proc_fini(net);
969 	free_percpu(net->mib.tls_statistics);
970 }
971 
972 static struct pernet_operations tls_proc_ops = {
973 	.init = tls_init_net,
974 	.exit = tls_exit_net,
975 };
976 
977 static struct tcp_ulp_ops tcp_tls_ulp_ops __read_mostly = {
978 	.name			= "tls",
979 	.owner			= THIS_MODULE,
980 	.init			= tls_init,
981 	.update			= tls_update,
982 	.get_info		= tls_get_info,
983 	.get_info_size		= tls_get_info_size,
984 };
985 
986 static int __init tls_register(void)
987 {
988 	int err;
989 
990 	err = register_pernet_subsys(&tls_proc_ops);
991 	if (err)
992 		return err;
993 
994 	tls_device_init();
995 	tcp_register_ulp(&tcp_tls_ulp_ops);
996 
997 	return 0;
998 }
999 
1000 static void __exit tls_unregister(void)
1001 {
1002 	tcp_unregister_ulp(&tcp_tls_ulp_ops);
1003 	tls_device_cleanup();
1004 	unregister_pernet_subsys(&tls_proc_ops);
1005 }
1006 
1007 module_init(tls_register);
1008 module_exit(tls_unregister);
1009