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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 
update_sk_prot(struct sock * sk,struct tls_context * ctx)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 
wait_on_pending_writer(struct sock * sk,long * timeo)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 
tls_push_sg(struct sock * sk,struct tls_context * ctx,struct scatterlist * sg,u16 first_offset,int flags)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 
tls_handle_open_record(struct sock * sk,int flags)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 
tls_proccess_cmsg(struct sock * sk,struct msghdr * msg,unsigned char * record_type)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 
tls_push_partial_record(struct sock * sk,struct tls_context * ctx,int flags)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 
tls_free_partial_record(struct sock * sk,struct tls_context * ctx)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 
tls_write_space(struct sock * sk)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  */
tls_ctx_free(struct sock * sk,struct tls_context * ctx)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 
tls_sk_proto_cleanup(struct sock * sk,struct tls_context * ctx,long timeo)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 
tls_sk_proto_close(struct sock * sk,long timeout)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 
do_tls_getsockopt_conf(struct sock * sk,char __user * optval,int __user * optlen,int tx)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 	default:
427 		rc = -EINVAL;
428 	}
429 
430 out:
431 	return rc;
432 }
433 
do_tls_getsockopt(struct sock * sk,int optname,char __user * optval,int __user * optlen)434 static int do_tls_getsockopt(struct sock *sk, int optname,
435 			     char __user *optval, int __user *optlen)
436 {
437 	int rc = 0;
438 
439 	switch (optname) {
440 	case TLS_TX:
441 	case TLS_RX:
442 		rc = do_tls_getsockopt_conf(sk, optval, optlen,
443 					    optname == TLS_TX);
444 		break;
445 	default:
446 		rc = -ENOPROTOOPT;
447 		break;
448 	}
449 	return rc;
450 }
451 
tls_getsockopt(struct sock * sk,int level,int optname,char __user * optval,int __user * optlen)452 static int tls_getsockopt(struct sock *sk, int level, int optname,
453 			  char __user *optval, int __user *optlen)
454 {
455 	struct tls_context *ctx = tls_get_ctx(sk);
456 
457 	if (level != SOL_TLS)
458 		return ctx->sk_proto->getsockopt(sk, level,
459 						 optname, optval, optlen);
460 
461 	return do_tls_getsockopt(sk, optname, optval, optlen);
462 }
463 
do_tls_setsockopt_conf(struct sock * sk,sockptr_t optval,unsigned int optlen,int tx)464 static int do_tls_setsockopt_conf(struct sock *sk, sockptr_t optval,
465 				  unsigned int optlen, int tx)
466 {
467 	struct tls_crypto_info *crypto_info;
468 	struct tls_crypto_info *alt_crypto_info;
469 	struct tls_context *ctx = tls_get_ctx(sk);
470 	size_t optsize;
471 	int rc = 0;
472 	int conf;
473 
474 	if (sockptr_is_null(optval) || (optlen < sizeof(*crypto_info))) {
475 		rc = -EINVAL;
476 		goto out;
477 	}
478 
479 	if (tx) {
480 		crypto_info = &ctx->crypto_send.info;
481 		alt_crypto_info = &ctx->crypto_recv.info;
482 	} else {
483 		crypto_info = &ctx->crypto_recv.info;
484 		alt_crypto_info = &ctx->crypto_send.info;
485 	}
486 
487 	/* Currently we don't support set crypto info more than one time */
488 	if (TLS_CRYPTO_INFO_READY(crypto_info)) {
489 		rc = -EBUSY;
490 		goto out;
491 	}
492 
493 	rc = copy_from_sockptr(crypto_info, optval, sizeof(*crypto_info));
494 	if (rc) {
495 		rc = -EFAULT;
496 		goto err_crypto_info;
497 	}
498 
499 	/* check version */
500 	if (crypto_info->version != TLS_1_2_VERSION &&
501 	    crypto_info->version != TLS_1_3_VERSION) {
502 		rc = -EINVAL;
503 		goto err_crypto_info;
504 	}
505 
506 	/* Ensure that TLS version and ciphers are same in both directions */
507 	if (TLS_CRYPTO_INFO_READY(alt_crypto_info)) {
508 		if (alt_crypto_info->version != crypto_info->version ||
509 		    alt_crypto_info->cipher_type != crypto_info->cipher_type) {
510 			rc = -EINVAL;
511 			goto err_crypto_info;
512 		}
513 	}
514 
515 	switch (crypto_info->cipher_type) {
516 	case TLS_CIPHER_AES_GCM_128:
517 		optsize = sizeof(struct tls12_crypto_info_aes_gcm_128);
518 		break;
519 	case TLS_CIPHER_AES_GCM_256: {
520 		optsize = sizeof(struct tls12_crypto_info_aes_gcm_256);
521 		break;
522 	}
523 	case TLS_CIPHER_AES_CCM_128:
524 		optsize = sizeof(struct tls12_crypto_info_aes_ccm_128);
525 		break;
526 	default:
527 		rc = -EINVAL;
528 		goto err_crypto_info;
529 	}
530 
531 	if (optlen != optsize) {
532 		rc = -EINVAL;
533 		goto err_crypto_info;
534 	}
535 
536 	rc = copy_from_sockptr_offset(crypto_info + 1, optval,
537 				      sizeof(*crypto_info),
538 				      optlen - sizeof(*crypto_info));
539 	if (rc) {
540 		rc = -EFAULT;
541 		goto err_crypto_info;
542 	}
543 
544 	if (tx) {
545 		rc = tls_set_device_offload(sk, ctx);
546 		conf = TLS_HW;
547 		if (!rc) {
548 			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSTXDEVICE);
549 			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSCURRTXDEVICE);
550 		} else {
551 			rc = tls_set_sw_offload(sk, ctx, 1);
552 			if (rc)
553 				goto err_crypto_info;
554 			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSTXSW);
555 			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSCURRTXSW);
556 			conf = TLS_SW;
557 		}
558 	} else {
559 		rc = tls_set_device_offload_rx(sk, ctx);
560 		conf = TLS_HW;
561 		if (!rc) {
562 			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSRXDEVICE);
563 			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSCURRRXDEVICE);
564 		} else {
565 			rc = tls_set_sw_offload(sk, ctx, 0);
566 			if (rc)
567 				goto err_crypto_info;
568 			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSRXSW);
569 			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSCURRRXSW);
570 			conf = TLS_SW;
571 		}
572 		tls_sw_strparser_arm(sk, ctx);
573 	}
574 
575 	if (tx)
576 		ctx->tx_conf = conf;
577 	else
578 		ctx->rx_conf = conf;
579 	update_sk_prot(sk, ctx);
580 	if (tx) {
581 		ctx->sk_write_space = sk->sk_write_space;
582 		sk->sk_write_space = tls_write_space;
583 	}
584 	goto out;
585 
586 err_crypto_info:
587 	memzero_explicit(crypto_info, sizeof(union tls_crypto_context));
588 out:
589 	return rc;
590 }
591 
do_tls_setsockopt(struct sock * sk,int optname,sockptr_t optval,unsigned int optlen)592 static int do_tls_setsockopt(struct sock *sk, int optname, sockptr_t optval,
593 			     unsigned int optlen)
594 {
595 	int rc = 0;
596 
597 	switch (optname) {
598 	case TLS_TX:
599 	case TLS_RX:
600 		lock_sock(sk);
601 		rc = do_tls_setsockopt_conf(sk, optval, optlen,
602 					    optname == TLS_TX);
603 		release_sock(sk);
604 		break;
605 	default:
606 		rc = -ENOPROTOOPT;
607 		break;
608 	}
609 	return rc;
610 }
611 
tls_setsockopt(struct sock * sk,int level,int optname,sockptr_t optval,unsigned int optlen)612 static int tls_setsockopt(struct sock *sk, int level, int optname,
613 			  sockptr_t optval, unsigned int optlen)
614 {
615 	struct tls_context *ctx = tls_get_ctx(sk);
616 
617 	if (level != SOL_TLS)
618 		return ctx->sk_proto->setsockopt(sk, level, optname, optval,
619 						 optlen);
620 
621 	return do_tls_setsockopt(sk, optname, optval, optlen);
622 }
623 
tls_ctx_create(struct sock * sk)624 struct tls_context *tls_ctx_create(struct sock *sk)
625 {
626 	struct inet_connection_sock *icsk = inet_csk(sk);
627 	struct tls_context *ctx;
628 
629 	ctx = kzalloc(sizeof(*ctx), GFP_ATOMIC);
630 	if (!ctx)
631 		return NULL;
632 
633 	mutex_init(&ctx->tx_lock);
634 	rcu_assign_pointer(icsk->icsk_ulp_data, ctx);
635 	ctx->sk_proto = READ_ONCE(sk->sk_prot);
636 	ctx->sk = sk;
637 	return ctx;
638 }
639 
build_proto_ops(struct proto_ops ops[TLS_NUM_CONFIG][TLS_NUM_CONFIG],const struct proto_ops * base)640 static void build_proto_ops(struct proto_ops ops[TLS_NUM_CONFIG][TLS_NUM_CONFIG],
641 			    const struct proto_ops *base)
642 {
643 	ops[TLS_BASE][TLS_BASE] = *base;
644 
645 	ops[TLS_SW  ][TLS_BASE] = ops[TLS_BASE][TLS_BASE];
646 	ops[TLS_SW  ][TLS_BASE].sendpage_locked	= tls_sw_sendpage_locked;
647 
648 	ops[TLS_BASE][TLS_SW  ] = ops[TLS_BASE][TLS_BASE];
649 	ops[TLS_BASE][TLS_SW  ].splice_read	= tls_sw_splice_read;
650 
651 	ops[TLS_SW  ][TLS_SW  ] = ops[TLS_SW  ][TLS_BASE];
652 	ops[TLS_SW  ][TLS_SW  ].splice_read	= tls_sw_splice_read;
653 
654 #ifdef CONFIG_TLS_DEVICE
655 	ops[TLS_HW  ][TLS_BASE] = ops[TLS_BASE][TLS_BASE];
656 	ops[TLS_HW  ][TLS_BASE].sendpage_locked	= NULL;
657 
658 	ops[TLS_HW  ][TLS_SW  ] = ops[TLS_BASE][TLS_SW  ];
659 	ops[TLS_HW  ][TLS_SW  ].sendpage_locked	= NULL;
660 
661 	ops[TLS_BASE][TLS_HW  ] = ops[TLS_BASE][TLS_SW  ];
662 
663 	ops[TLS_SW  ][TLS_HW  ] = ops[TLS_SW  ][TLS_SW  ];
664 
665 	ops[TLS_HW  ][TLS_HW  ] = ops[TLS_HW  ][TLS_SW  ];
666 	ops[TLS_HW  ][TLS_HW  ].sendpage_locked	= NULL;
667 #endif
668 #ifdef CONFIG_TLS_TOE
669 	ops[TLS_HW_RECORD][TLS_HW_RECORD] = *base;
670 #endif
671 }
672 
tls_build_proto(struct sock * sk)673 static void tls_build_proto(struct sock *sk)
674 {
675 	int ip_ver = sk->sk_family == AF_INET6 ? TLSV6 : TLSV4;
676 	struct proto *prot = READ_ONCE(sk->sk_prot);
677 
678 	/* Build IPv6 TLS whenever the address of tcpv6 _prot changes */
679 	if (ip_ver == TLSV6 &&
680 	    unlikely(prot != smp_load_acquire(&saved_tcpv6_prot))) {
681 		mutex_lock(&tcpv6_prot_mutex);
682 		if (likely(prot != saved_tcpv6_prot)) {
683 			build_protos(tls_prots[TLSV6], prot);
684 			build_proto_ops(tls_proto_ops[TLSV6],
685 					sk->sk_socket->ops);
686 			smp_store_release(&saved_tcpv6_prot, prot);
687 		}
688 		mutex_unlock(&tcpv6_prot_mutex);
689 	}
690 
691 	if (ip_ver == TLSV4 &&
692 	    unlikely(prot != smp_load_acquire(&saved_tcpv4_prot))) {
693 		mutex_lock(&tcpv4_prot_mutex);
694 		if (likely(prot != saved_tcpv4_prot)) {
695 			build_protos(tls_prots[TLSV4], prot);
696 			build_proto_ops(tls_proto_ops[TLSV4],
697 					sk->sk_socket->ops);
698 			smp_store_release(&saved_tcpv4_prot, prot);
699 		}
700 		mutex_unlock(&tcpv4_prot_mutex);
701 	}
702 }
703 
build_protos(struct proto prot[TLS_NUM_CONFIG][TLS_NUM_CONFIG],const struct proto * base)704 static void build_protos(struct proto prot[TLS_NUM_CONFIG][TLS_NUM_CONFIG],
705 			 const struct proto *base)
706 {
707 	prot[TLS_BASE][TLS_BASE] = *base;
708 	prot[TLS_BASE][TLS_BASE].setsockopt	= tls_setsockopt;
709 	prot[TLS_BASE][TLS_BASE].getsockopt	= tls_getsockopt;
710 	prot[TLS_BASE][TLS_BASE].close		= tls_sk_proto_close;
711 
712 	prot[TLS_SW][TLS_BASE] = prot[TLS_BASE][TLS_BASE];
713 	prot[TLS_SW][TLS_BASE].sendmsg		= tls_sw_sendmsg;
714 	prot[TLS_SW][TLS_BASE].sendpage		= tls_sw_sendpage;
715 
716 	prot[TLS_BASE][TLS_SW] = prot[TLS_BASE][TLS_BASE];
717 	prot[TLS_BASE][TLS_SW].recvmsg		  = tls_sw_recvmsg;
718 	prot[TLS_BASE][TLS_SW].stream_memory_read = tls_sw_stream_read;
719 	prot[TLS_BASE][TLS_SW].close		  = tls_sk_proto_close;
720 
721 	prot[TLS_SW][TLS_SW] = prot[TLS_SW][TLS_BASE];
722 	prot[TLS_SW][TLS_SW].recvmsg		= tls_sw_recvmsg;
723 	prot[TLS_SW][TLS_SW].stream_memory_read	= tls_sw_stream_read;
724 	prot[TLS_SW][TLS_SW].close		= tls_sk_proto_close;
725 
726 #ifdef CONFIG_TLS_DEVICE
727 	prot[TLS_HW][TLS_BASE] = prot[TLS_BASE][TLS_BASE];
728 	prot[TLS_HW][TLS_BASE].sendmsg		= tls_device_sendmsg;
729 	prot[TLS_HW][TLS_BASE].sendpage		= tls_device_sendpage;
730 
731 	prot[TLS_HW][TLS_SW] = prot[TLS_BASE][TLS_SW];
732 	prot[TLS_HW][TLS_SW].sendmsg		= tls_device_sendmsg;
733 	prot[TLS_HW][TLS_SW].sendpage		= tls_device_sendpage;
734 
735 	prot[TLS_BASE][TLS_HW] = prot[TLS_BASE][TLS_SW];
736 
737 	prot[TLS_SW][TLS_HW] = prot[TLS_SW][TLS_SW];
738 
739 	prot[TLS_HW][TLS_HW] = prot[TLS_HW][TLS_SW];
740 #endif
741 #ifdef CONFIG_TLS_TOE
742 	prot[TLS_HW_RECORD][TLS_HW_RECORD] = *base;
743 	prot[TLS_HW_RECORD][TLS_HW_RECORD].hash		= tls_toe_hash;
744 	prot[TLS_HW_RECORD][TLS_HW_RECORD].unhash	= tls_toe_unhash;
745 #endif
746 }
747 
tls_init(struct sock * sk)748 static int tls_init(struct sock *sk)
749 {
750 	struct tls_context *ctx;
751 	int rc = 0;
752 
753 	tls_build_proto(sk);
754 
755 #ifdef CONFIG_TLS_TOE
756 	if (tls_toe_bypass(sk))
757 		return 0;
758 #endif
759 
760 	/* The TLS ulp is currently supported only for TCP sockets
761 	 * in ESTABLISHED state.
762 	 * Supporting sockets in LISTEN state will require us
763 	 * to modify the accept implementation to clone rather then
764 	 * share the ulp context.
765 	 */
766 	if (sk->sk_state != TCP_ESTABLISHED)
767 		return -ENOTCONN;
768 
769 	/* allocate tls context */
770 	write_lock_bh(&sk->sk_callback_lock);
771 	ctx = tls_ctx_create(sk);
772 	if (!ctx) {
773 		rc = -ENOMEM;
774 		goto out;
775 	}
776 
777 	ctx->tx_conf = TLS_BASE;
778 	ctx->rx_conf = TLS_BASE;
779 	update_sk_prot(sk, ctx);
780 out:
781 	write_unlock_bh(&sk->sk_callback_lock);
782 	return rc;
783 }
784 
tls_update(struct sock * sk,struct proto * p,void (* write_space)(struct sock * sk))785 static void tls_update(struct sock *sk, struct proto *p,
786 		       void (*write_space)(struct sock *sk))
787 {
788 	struct tls_context *ctx;
789 
790 	ctx = tls_get_ctx(sk);
791 	if (likely(ctx)) {
792 		ctx->sk_write_space = write_space;
793 		ctx->sk_proto = p;
794 	} else {
795 		/* Pairs with lockless read in sk_clone_lock(). */
796 		WRITE_ONCE(sk->sk_prot, p);
797 		sk->sk_write_space = write_space;
798 	}
799 }
800 
tls_get_info(const struct sock * sk,struct sk_buff * skb)801 static int tls_get_info(const struct sock *sk, struct sk_buff *skb)
802 {
803 	u16 version, cipher_type;
804 	struct tls_context *ctx;
805 	struct nlattr *start;
806 	int err;
807 
808 	start = nla_nest_start_noflag(skb, INET_ULP_INFO_TLS);
809 	if (!start)
810 		return -EMSGSIZE;
811 
812 	rcu_read_lock();
813 	ctx = rcu_dereference(inet_csk(sk)->icsk_ulp_data);
814 	if (!ctx) {
815 		err = 0;
816 		goto nla_failure;
817 	}
818 	version = ctx->prot_info.version;
819 	if (version) {
820 		err = nla_put_u16(skb, TLS_INFO_VERSION, version);
821 		if (err)
822 			goto nla_failure;
823 	}
824 	cipher_type = ctx->prot_info.cipher_type;
825 	if (cipher_type) {
826 		err = nla_put_u16(skb, TLS_INFO_CIPHER, cipher_type);
827 		if (err)
828 			goto nla_failure;
829 	}
830 	err = nla_put_u16(skb, TLS_INFO_TXCONF, tls_user_config(ctx, true));
831 	if (err)
832 		goto nla_failure;
833 
834 	err = nla_put_u16(skb, TLS_INFO_RXCONF, tls_user_config(ctx, false));
835 	if (err)
836 		goto nla_failure;
837 
838 	rcu_read_unlock();
839 	nla_nest_end(skb, start);
840 	return 0;
841 
842 nla_failure:
843 	rcu_read_unlock();
844 	nla_nest_cancel(skb, start);
845 	return err;
846 }
847 
tls_get_info_size(const struct sock * sk)848 static size_t tls_get_info_size(const struct sock *sk)
849 {
850 	size_t size = 0;
851 
852 	size += nla_total_size(0) +		/* INET_ULP_INFO_TLS */
853 		nla_total_size(sizeof(u16)) +	/* TLS_INFO_VERSION */
854 		nla_total_size(sizeof(u16)) +	/* TLS_INFO_CIPHER */
855 		nla_total_size(sizeof(u16)) +	/* TLS_INFO_RXCONF */
856 		nla_total_size(sizeof(u16)) +	/* TLS_INFO_TXCONF */
857 		0;
858 
859 	return size;
860 }
861 
tls_init_net(struct net * net)862 static int __net_init tls_init_net(struct net *net)
863 {
864 	int err;
865 
866 	net->mib.tls_statistics = alloc_percpu(struct linux_tls_mib);
867 	if (!net->mib.tls_statistics)
868 		return -ENOMEM;
869 
870 	err = tls_proc_init(net);
871 	if (err)
872 		goto err_free_stats;
873 
874 	return 0;
875 err_free_stats:
876 	free_percpu(net->mib.tls_statistics);
877 	return err;
878 }
879 
tls_exit_net(struct net * net)880 static void __net_exit tls_exit_net(struct net *net)
881 {
882 	tls_proc_fini(net);
883 	free_percpu(net->mib.tls_statistics);
884 }
885 
886 static struct pernet_operations tls_proc_ops = {
887 	.init = tls_init_net,
888 	.exit = tls_exit_net,
889 };
890 
891 static struct tcp_ulp_ops tcp_tls_ulp_ops __read_mostly = {
892 	.name			= "tls",
893 	.owner			= THIS_MODULE,
894 	.init			= tls_init,
895 	.update			= tls_update,
896 	.get_info		= tls_get_info,
897 	.get_info_size		= tls_get_info_size,
898 };
899 
tls_register(void)900 static int __init tls_register(void)
901 {
902 	int err;
903 
904 	err = register_pernet_subsys(&tls_proc_ops);
905 	if (err)
906 		return err;
907 
908 	tls_device_init();
909 	tcp_register_ulp(&tcp_tls_ulp_ops);
910 
911 	return 0;
912 }
913 
tls_unregister(void)914 static void __exit tls_unregister(void)
915 {
916 	tcp_unregister_ulp(&tcp_tls_ulp_ops);
917 	tls_device_cleanup();
918 	unregister_pernet_subsys(&tls_proc_ops);
919 }
920 
921 module_init(tls_register);
922 module_exit(tls_unregister);
923