xref: /openbmc/linux/net/tls/tls_main.c (revision 3b2e6a93)
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 		rc = -EINVAL;
558 		goto out;
559 	}
560 
561 	if (tx) {
562 		crypto_info = &ctx->crypto_send.info;
563 		alt_crypto_info = &ctx->crypto_recv.info;
564 	} else {
565 		crypto_info = &ctx->crypto_recv.info;
566 		alt_crypto_info = &ctx->crypto_send.info;
567 	}
568 
569 	/* Currently we don't support set crypto info more than one time */
570 	if (TLS_CRYPTO_INFO_READY(crypto_info)) {
571 		rc = -EBUSY;
572 		goto out;
573 	}
574 
575 	rc = copy_from_sockptr(crypto_info, optval, sizeof(*crypto_info));
576 	if (rc) {
577 		rc = -EFAULT;
578 		goto err_crypto_info;
579 	}
580 
581 	/* check version */
582 	if (crypto_info->version != TLS_1_2_VERSION &&
583 	    crypto_info->version != TLS_1_3_VERSION) {
584 		rc = -EINVAL;
585 		goto err_crypto_info;
586 	}
587 
588 	/* Ensure that TLS version and ciphers are same in both directions */
589 	if (TLS_CRYPTO_INFO_READY(alt_crypto_info)) {
590 		if (alt_crypto_info->version != crypto_info->version ||
591 		    alt_crypto_info->cipher_type != crypto_info->cipher_type) {
592 			rc = -EINVAL;
593 			goto err_crypto_info;
594 		}
595 	}
596 
597 	switch (crypto_info->cipher_type) {
598 	case TLS_CIPHER_AES_GCM_128:
599 		optsize = sizeof(struct tls12_crypto_info_aes_gcm_128);
600 		break;
601 	case TLS_CIPHER_AES_GCM_256: {
602 		optsize = sizeof(struct tls12_crypto_info_aes_gcm_256);
603 		break;
604 	}
605 	case TLS_CIPHER_AES_CCM_128:
606 		optsize = sizeof(struct tls12_crypto_info_aes_ccm_128);
607 		break;
608 	case TLS_CIPHER_CHACHA20_POLY1305:
609 		optsize = sizeof(struct tls12_crypto_info_chacha20_poly1305);
610 		break;
611 	case TLS_CIPHER_SM4_GCM:
612 		optsize = sizeof(struct tls12_crypto_info_sm4_gcm);
613 		break;
614 	case TLS_CIPHER_SM4_CCM:
615 		optsize = sizeof(struct tls12_crypto_info_sm4_ccm);
616 		break;
617 	default:
618 		rc = -EINVAL;
619 		goto err_crypto_info;
620 	}
621 
622 	if (optlen != optsize) {
623 		rc = -EINVAL;
624 		goto err_crypto_info;
625 	}
626 
627 	rc = copy_from_sockptr_offset(crypto_info + 1, optval,
628 				      sizeof(*crypto_info),
629 				      optlen - sizeof(*crypto_info));
630 	if (rc) {
631 		rc = -EFAULT;
632 		goto err_crypto_info;
633 	}
634 
635 	if (tx) {
636 		rc = tls_set_device_offload(sk, ctx);
637 		conf = TLS_HW;
638 		if (!rc) {
639 			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSTXDEVICE);
640 			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSCURRTXDEVICE);
641 		} else {
642 			rc = tls_set_sw_offload(sk, ctx, 1);
643 			if (rc)
644 				goto err_crypto_info;
645 			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSTXSW);
646 			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSCURRTXSW);
647 			conf = TLS_SW;
648 		}
649 	} else {
650 		rc = tls_set_device_offload_rx(sk, ctx);
651 		conf = TLS_HW;
652 		if (!rc) {
653 			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSRXDEVICE);
654 			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSCURRRXDEVICE);
655 		} else {
656 			rc = tls_set_sw_offload(sk, ctx, 0);
657 			if (rc)
658 				goto err_crypto_info;
659 			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSRXSW);
660 			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSCURRRXSW);
661 			conf = TLS_SW;
662 		}
663 		tls_sw_strparser_arm(sk, ctx);
664 	}
665 
666 	if (tx)
667 		ctx->tx_conf = conf;
668 	else
669 		ctx->rx_conf = conf;
670 	update_sk_prot(sk, ctx);
671 	if (tx) {
672 		ctx->sk_write_space = sk->sk_write_space;
673 		sk->sk_write_space = tls_write_space;
674 	}
675 	goto out;
676 
677 err_crypto_info:
678 	memzero_explicit(crypto_info, sizeof(union tls_crypto_context));
679 out:
680 	return rc;
681 }
682 
683 static int do_tls_setsockopt(struct sock *sk, int optname, sockptr_t optval,
684 			     unsigned int optlen)
685 {
686 	int rc = 0;
687 
688 	switch (optname) {
689 	case TLS_TX:
690 	case TLS_RX:
691 		lock_sock(sk);
692 		rc = do_tls_setsockopt_conf(sk, optval, optlen,
693 					    optname == TLS_TX);
694 		release_sock(sk);
695 		break;
696 	default:
697 		rc = -ENOPROTOOPT;
698 		break;
699 	}
700 	return rc;
701 }
702 
703 static int tls_setsockopt(struct sock *sk, int level, int optname,
704 			  sockptr_t optval, unsigned int optlen)
705 {
706 	struct tls_context *ctx = tls_get_ctx(sk);
707 
708 	if (level != SOL_TLS)
709 		return ctx->sk_proto->setsockopt(sk, level, optname, optval,
710 						 optlen);
711 
712 	return do_tls_setsockopt(sk, optname, optval, optlen);
713 }
714 
715 struct tls_context *tls_ctx_create(struct sock *sk)
716 {
717 	struct inet_connection_sock *icsk = inet_csk(sk);
718 	struct tls_context *ctx;
719 
720 	ctx = kzalloc(sizeof(*ctx), GFP_ATOMIC);
721 	if (!ctx)
722 		return NULL;
723 
724 	mutex_init(&ctx->tx_lock);
725 	rcu_assign_pointer(icsk->icsk_ulp_data, ctx);
726 	ctx->sk_proto = READ_ONCE(sk->sk_prot);
727 	ctx->sk = sk;
728 	return ctx;
729 }
730 
731 static void build_proto_ops(struct proto_ops ops[TLS_NUM_CONFIG][TLS_NUM_CONFIG],
732 			    const struct proto_ops *base)
733 {
734 	ops[TLS_BASE][TLS_BASE] = *base;
735 
736 	ops[TLS_SW  ][TLS_BASE] = ops[TLS_BASE][TLS_BASE];
737 	ops[TLS_SW  ][TLS_BASE].sendpage_locked	= tls_sw_sendpage_locked;
738 
739 	ops[TLS_BASE][TLS_SW  ] = ops[TLS_BASE][TLS_BASE];
740 	ops[TLS_BASE][TLS_SW  ].splice_read	= tls_sw_splice_read;
741 
742 	ops[TLS_SW  ][TLS_SW  ] = ops[TLS_SW  ][TLS_BASE];
743 	ops[TLS_SW  ][TLS_SW  ].splice_read	= tls_sw_splice_read;
744 
745 #ifdef CONFIG_TLS_DEVICE
746 	ops[TLS_HW  ][TLS_BASE] = ops[TLS_BASE][TLS_BASE];
747 	ops[TLS_HW  ][TLS_BASE].sendpage_locked	= NULL;
748 
749 	ops[TLS_HW  ][TLS_SW  ] = ops[TLS_BASE][TLS_SW  ];
750 	ops[TLS_HW  ][TLS_SW  ].sendpage_locked	= NULL;
751 
752 	ops[TLS_BASE][TLS_HW  ] = ops[TLS_BASE][TLS_SW  ];
753 
754 	ops[TLS_SW  ][TLS_HW  ] = ops[TLS_SW  ][TLS_SW  ];
755 
756 	ops[TLS_HW  ][TLS_HW  ] = ops[TLS_HW  ][TLS_SW  ];
757 	ops[TLS_HW  ][TLS_HW  ].sendpage_locked	= NULL;
758 #endif
759 #ifdef CONFIG_TLS_TOE
760 	ops[TLS_HW_RECORD][TLS_HW_RECORD] = *base;
761 #endif
762 }
763 
764 static void tls_build_proto(struct sock *sk)
765 {
766 	int ip_ver = sk->sk_family == AF_INET6 ? TLSV6 : TLSV4;
767 	struct proto *prot = READ_ONCE(sk->sk_prot);
768 
769 	/* Build IPv6 TLS whenever the address of tcpv6 _prot changes */
770 	if (ip_ver == TLSV6 &&
771 	    unlikely(prot != smp_load_acquire(&saved_tcpv6_prot))) {
772 		mutex_lock(&tcpv6_prot_mutex);
773 		if (likely(prot != saved_tcpv6_prot)) {
774 			build_protos(tls_prots[TLSV6], prot);
775 			build_proto_ops(tls_proto_ops[TLSV6],
776 					sk->sk_socket->ops);
777 			smp_store_release(&saved_tcpv6_prot, prot);
778 		}
779 		mutex_unlock(&tcpv6_prot_mutex);
780 	}
781 
782 	if (ip_ver == TLSV4 &&
783 	    unlikely(prot != smp_load_acquire(&saved_tcpv4_prot))) {
784 		mutex_lock(&tcpv4_prot_mutex);
785 		if (likely(prot != saved_tcpv4_prot)) {
786 			build_protos(tls_prots[TLSV4], prot);
787 			build_proto_ops(tls_proto_ops[TLSV4],
788 					sk->sk_socket->ops);
789 			smp_store_release(&saved_tcpv4_prot, prot);
790 		}
791 		mutex_unlock(&tcpv4_prot_mutex);
792 	}
793 }
794 
795 static void build_protos(struct proto prot[TLS_NUM_CONFIG][TLS_NUM_CONFIG],
796 			 const struct proto *base)
797 {
798 	prot[TLS_BASE][TLS_BASE] = *base;
799 	prot[TLS_BASE][TLS_BASE].setsockopt	= tls_setsockopt;
800 	prot[TLS_BASE][TLS_BASE].getsockopt	= tls_getsockopt;
801 	prot[TLS_BASE][TLS_BASE].close		= tls_sk_proto_close;
802 
803 	prot[TLS_SW][TLS_BASE] = prot[TLS_BASE][TLS_BASE];
804 	prot[TLS_SW][TLS_BASE].sendmsg		= tls_sw_sendmsg;
805 	prot[TLS_SW][TLS_BASE].sendpage		= tls_sw_sendpage;
806 
807 	prot[TLS_BASE][TLS_SW] = prot[TLS_BASE][TLS_BASE];
808 	prot[TLS_BASE][TLS_SW].recvmsg		  = tls_sw_recvmsg;
809 	prot[TLS_BASE][TLS_SW].sock_is_readable   = tls_sw_sock_is_readable;
810 	prot[TLS_BASE][TLS_SW].close		  = tls_sk_proto_close;
811 
812 	prot[TLS_SW][TLS_SW] = prot[TLS_SW][TLS_BASE];
813 	prot[TLS_SW][TLS_SW].recvmsg		= tls_sw_recvmsg;
814 	prot[TLS_SW][TLS_SW].sock_is_readable   = tls_sw_sock_is_readable;
815 	prot[TLS_SW][TLS_SW].close		= tls_sk_proto_close;
816 
817 #ifdef CONFIG_TLS_DEVICE
818 	prot[TLS_HW][TLS_BASE] = prot[TLS_BASE][TLS_BASE];
819 	prot[TLS_HW][TLS_BASE].sendmsg		= tls_device_sendmsg;
820 	prot[TLS_HW][TLS_BASE].sendpage		= tls_device_sendpage;
821 
822 	prot[TLS_HW][TLS_SW] = prot[TLS_BASE][TLS_SW];
823 	prot[TLS_HW][TLS_SW].sendmsg		= tls_device_sendmsg;
824 	prot[TLS_HW][TLS_SW].sendpage		= tls_device_sendpage;
825 
826 	prot[TLS_BASE][TLS_HW] = prot[TLS_BASE][TLS_SW];
827 
828 	prot[TLS_SW][TLS_HW] = prot[TLS_SW][TLS_SW];
829 
830 	prot[TLS_HW][TLS_HW] = prot[TLS_HW][TLS_SW];
831 #endif
832 #ifdef CONFIG_TLS_TOE
833 	prot[TLS_HW_RECORD][TLS_HW_RECORD] = *base;
834 	prot[TLS_HW_RECORD][TLS_HW_RECORD].hash		= tls_toe_hash;
835 	prot[TLS_HW_RECORD][TLS_HW_RECORD].unhash	= tls_toe_unhash;
836 #endif
837 }
838 
839 static int tls_init(struct sock *sk)
840 {
841 	struct tls_context *ctx;
842 	int rc = 0;
843 
844 	tls_build_proto(sk);
845 
846 #ifdef CONFIG_TLS_TOE
847 	if (tls_toe_bypass(sk))
848 		return 0;
849 #endif
850 
851 	/* The TLS ulp is currently supported only for TCP sockets
852 	 * in ESTABLISHED state.
853 	 * Supporting sockets in LISTEN state will require us
854 	 * to modify the accept implementation to clone rather then
855 	 * share the ulp context.
856 	 */
857 	if (sk->sk_state != TCP_ESTABLISHED)
858 		return -ENOTCONN;
859 
860 	/* allocate tls context */
861 	write_lock_bh(&sk->sk_callback_lock);
862 	ctx = tls_ctx_create(sk);
863 	if (!ctx) {
864 		rc = -ENOMEM;
865 		goto out;
866 	}
867 
868 	ctx->tx_conf = TLS_BASE;
869 	ctx->rx_conf = TLS_BASE;
870 	update_sk_prot(sk, ctx);
871 out:
872 	write_unlock_bh(&sk->sk_callback_lock);
873 	return rc;
874 }
875 
876 static void tls_update(struct sock *sk, struct proto *p,
877 		       void (*write_space)(struct sock *sk))
878 {
879 	struct tls_context *ctx;
880 
881 	ctx = tls_get_ctx(sk);
882 	if (likely(ctx)) {
883 		ctx->sk_write_space = write_space;
884 		ctx->sk_proto = p;
885 	} else {
886 		/* Pairs with lockless read in sk_clone_lock(). */
887 		WRITE_ONCE(sk->sk_prot, p);
888 		sk->sk_write_space = write_space;
889 	}
890 }
891 
892 static int tls_get_info(const struct sock *sk, struct sk_buff *skb)
893 {
894 	u16 version, cipher_type;
895 	struct tls_context *ctx;
896 	struct nlattr *start;
897 	int err;
898 
899 	start = nla_nest_start_noflag(skb, INET_ULP_INFO_TLS);
900 	if (!start)
901 		return -EMSGSIZE;
902 
903 	rcu_read_lock();
904 	ctx = rcu_dereference(inet_csk(sk)->icsk_ulp_data);
905 	if (!ctx) {
906 		err = 0;
907 		goto nla_failure;
908 	}
909 	version = ctx->prot_info.version;
910 	if (version) {
911 		err = nla_put_u16(skb, TLS_INFO_VERSION, version);
912 		if (err)
913 			goto nla_failure;
914 	}
915 	cipher_type = ctx->prot_info.cipher_type;
916 	if (cipher_type) {
917 		err = nla_put_u16(skb, TLS_INFO_CIPHER, cipher_type);
918 		if (err)
919 			goto nla_failure;
920 	}
921 	err = nla_put_u16(skb, TLS_INFO_TXCONF, tls_user_config(ctx, true));
922 	if (err)
923 		goto nla_failure;
924 
925 	err = nla_put_u16(skb, TLS_INFO_RXCONF, tls_user_config(ctx, false));
926 	if (err)
927 		goto nla_failure;
928 
929 	rcu_read_unlock();
930 	nla_nest_end(skb, start);
931 	return 0;
932 
933 nla_failure:
934 	rcu_read_unlock();
935 	nla_nest_cancel(skb, start);
936 	return err;
937 }
938 
939 static size_t tls_get_info_size(const struct sock *sk)
940 {
941 	size_t size = 0;
942 
943 	size += nla_total_size(0) +		/* INET_ULP_INFO_TLS */
944 		nla_total_size(sizeof(u16)) +	/* TLS_INFO_VERSION */
945 		nla_total_size(sizeof(u16)) +	/* TLS_INFO_CIPHER */
946 		nla_total_size(sizeof(u16)) +	/* TLS_INFO_RXCONF */
947 		nla_total_size(sizeof(u16)) +	/* TLS_INFO_TXCONF */
948 		0;
949 
950 	return size;
951 }
952 
953 static int __net_init tls_init_net(struct net *net)
954 {
955 	int err;
956 
957 	net->mib.tls_statistics = alloc_percpu(struct linux_tls_mib);
958 	if (!net->mib.tls_statistics)
959 		return -ENOMEM;
960 
961 	err = tls_proc_init(net);
962 	if (err)
963 		goto err_free_stats;
964 
965 	return 0;
966 err_free_stats:
967 	free_percpu(net->mib.tls_statistics);
968 	return err;
969 }
970 
971 static void __net_exit tls_exit_net(struct net *net)
972 {
973 	tls_proc_fini(net);
974 	free_percpu(net->mib.tls_statistics);
975 }
976 
977 static struct pernet_operations tls_proc_ops = {
978 	.init = tls_init_net,
979 	.exit = tls_exit_net,
980 };
981 
982 static struct tcp_ulp_ops tcp_tls_ulp_ops __read_mostly = {
983 	.name			= "tls",
984 	.owner			= THIS_MODULE,
985 	.init			= tls_init,
986 	.update			= tls_update,
987 	.get_info		= tls_get_info,
988 	.get_info_size		= tls_get_info_size,
989 };
990 
991 static int __init tls_register(void)
992 {
993 	int err;
994 
995 	err = register_pernet_subsys(&tls_proc_ops);
996 	if (err)
997 		return err;
998 
999 	tls_device_init();
1000 	tcp_register_ulp(&tcp_tls_ulp_ops);
1001 
1002 	return 0;
1003 }
1004 
1005 static void __exit tls_unregister(void)
1006 {
1007 	tcp_unregister_ulp(&tcp_tls_ulp_ops);
1008 	tls_device_cleanup();
1009 	unregister_pernet_subsys(&tls_proc_ops);
1010 }
1011 
1012 module_init(tls_register);
1013 module_exit(tls_unregister);
1014