xref: /linux/net/tls/tls_main.c (revision 6af91e3d2cfc8bb579b1aa2d22cd91f8c34acdf6)
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 #include "tls.h"
49 
50 MODULE_AUTHOR("Mellanox Technologies");
51 MODULE_DESCRIPTION("Transport Layer Security Support");
52 MODULE_LICENSE("Dual BSD/GPL");
53 MODULE_ALIAS_TCP_ULP("tls");
54 
55 enum {
56 	TLSV4,
57 	TLSV6,
58 	TLS_NUM_PROTS,
59 };
60 
61 #define CHECK_CIPHER_DESC(cipher,ci)				\
62 	static_assert(cipher ## _IV_SIZE <= TLS_MAX_IV_SIZE);		\
63 	static_assert(cipher ## _SALT_SIZE <= TLS_MAX_SALT_SIZE);		\
64 	static_assert(cipher ## _REC_SEQ_SIZE <= TLS_MAX_REC_SEQ_SIZE);	\
65 	static_assert(cipher ## _TAG_SIZE == TLS_TAG_SIZE);		\
66 	static_assert(sizeof_field(struct ci, iv) == cipher ## _IV_SIZE);	\
67 	static_assert(sizeof_field(struct ci, key) == cipher ## _KEY_SIZE);	\
68 	static_assert(sizeof_field(struct ci, salt) == cipher ## _SALT_SIZE);	\
69 	static_assert(sizeof_field(struct ci, rec_seq) == cipher ## _REC_SEQ_SIZE);
70 
71 #define __CIPHER_DESC(ci) \
72 	.iv_offset = offsetof(struct ci, iv), \
73 	.key_offset = offsetof(struct ci, key), \
74 	.salt_offset = offsetof(struct ci, salt), \
75 	.rec_seq_offset = offsetof(struct ci, rec_seq), \
76 	.crypto_info = sizeof(struct ci)
77 
78 #define CIPHER_DESC(cipher,ci,algname,_offloadable) [cipher - TLS_CIPHER_MIN] = {	\
79 	.nonce = cipher ## _IV_SIZE, \
80 	.iv = cipher ## _IV_SIZE, \
81 	.key = cipher ## _KEY_SIZE, \
82 	.salt = cipher ## _SALT_SIZE, \
83 	.tag = cipher ## _TAG_SIZE, \
84 	.rec_seq = cipher ## _REC_SEQ_SIZE, \
85 	.cipher_name = algname,	\
86 	.offloadable = _offloadable, \
87 	__CIPHER_DESC(ci), \
88 }
89 
90 #define CIPHER_DESC_NONCE0(cipher,ci,algname,_offloadable) [cipher - TLS_CIPHER_MIN] = { \
91 	.nonce = 0, \
92 	.iv = cipher ## _IV_SIZE, \
93 	.key = cipher ## _KEY_SIZE, \
94 	.salt = cipher ## _SALT_SIZE, \
95 	.tag = cipher ## _TAG_SIZE, \
96 	.rec_seq = cipher ## _REC_SEQ_SIZE, \
97 	.cipher_name = algname,	\
98 	.offloadable = _offloadable, \
99 	__CIPHER_DESC(ci), \
100 }
101 
102 const struct tls_cipher_desc tls_cipher_desc[TLS_CIPHER_MAX + 1 - TLS_CIPHER_MIN] = {
103 	CIPHER_DESC(TLS_CIPHER_AES_GCM_128, tls12_crypto_info_aes_gcm_128, "gcm(aes)", true),
104 	CIPHER_DESC(TLS_CIPHER_AES_GCM_256, tls12_crypto_info_aes_gcm_256, "gcm(aes)", true),
105 	CIPHER_DESC(TLS_CIPHER_AES_CCM_128, tls12_crypto_info_aes_ccm_128, "ccm(aes)", false),
106 	CIPHER_DESC_NONCE0(TLS_CIPHER_CHACHA20_POLY1305, tls12_crypto_info_chacha20_poly1305, "rfc7539(chacha20,poly1305)", false),
107 	CIPHER_DESC(TLS_CIPHER_SM4_GCM, tls12_crypto_info_sm4_gcm, "gcm(sm4)", false),
108 	CIPHER_DESC(TLS_CIPHER_SM4_CCM, tls12_crypto_info_sm4_ccm, "ccm(sm4)", false),
109 	CIPHER_DESC(TLS_CIPHER_ARIA_GCM_128, tls12_crypto_info_aria_gcm_128, "gcm(aria)", false),
110 	CIPHER_DESC(TLS_CIPHER_ARIA_GCM_256, tls12_crypto_info_aria_gcm_256, "gcm(aria)", false),
111 };
112 
113 CHECK_CIPHER_DESC(TLS_CIPHER_AES_GCM_128, tls12_crypto_info_aes_gcm_128);
114 CHECK_CIPHER_DESC(TLS_CIPHER_AES_GCM_256, tls12_crypto_info_aes_gcm_256);
115 CHECK_CIPHER_DESC(TLS_CIPHER_AES_CCM_128, tls12_crypto_info_aes_ccm_128);
116 CHECK_CIPHER_DESC(TLS_CIPHER_CHACHA20_POLY1305, tls12_crypto_info_chacha20_poly1305);
117 CHECK_CIPHER_DESC(TLS_CIPHER_SM4_GCM, tls12_crypto_info_sm4_gcm);
118 CHECK_CIPHER_DESC(TLS_CIPHER_SM4_CCM, tls12_crypto_info_sm4_ccm);
119 CHECK_CIPHER_DESC(TLS_CIPHER_ARIA_GCM_128, tls12_crypto_info_aria_gcm_128);
120 CHECK_CIPHER_DESC(TLS_CIPHER_ARIA_GCM_256, tls12_crypto_info_aria_gcm_256);
121 
122 static const struct proto *saved_tcpv6_prot;
123 static DEFINE_MUTEX(tcpv6_prot_mutex);
124 static const struct proto *saved_tcpv4_prot;
125 static DEFINE_MUTEX(tcpv4_prot_mutex);
126 static struct proto tls_prots[TLS_NUM_PROTS][TLS_NUM_CONFIG][TLS_NUM_CONFIG];
127 static struct proto_ops tls_proto_ops[TLS_NUM_PROTS][TLS_NUM_CONFIG][TLS_NUM_CONFIG];
128 static void build_protos(struct proto prot[TLS_NUM_CONFIG][TLS_NUM_CONFIG],
129 			 const struct proto *base);
130 
131 void update_sk_prot(struct sock *sk, struct tls_context *ctx)
132 {
133 	int ip_ver = sk->sk_family == AF_INET6 ? TLSV6 : TLSV4;
134 
135 	WRITE_ONCE(sk->sk_prot,
136 		   &tls_prots[ip_ver][ctx->tx_conf][ctx->rx_conf]);
137 	WRITE_ONCE(sk->sk_socket->ops,
138 		   &tls_proto_ops[ip_ver][ctx->tx_conf][ctx->rx_conf]);
139 }
140 
141 int wait_on_pending_writer(struct sock *sk, long *timeo)
142 {
143 	DEFINE_WAIT_FUNC(wait, woken_wake_function);
144 	int ret, rc = 0;
145 
146 	add_wait_queue(sk_sleep(sk), &wait);
147 	while (1) {
148 		if (!*timeo) {
149 			rc = -EAGAIN;
150 			break;
151 		}
152 
153 		if (signal_pending(current)) {
154 			rc = sock_intr_errno(*timeo);
155 			break;
156 		}
157 
158 		ret = sk_wait_event(sk, timeo,
159 				    !READ_ONCE(sk->sk_write_pending), &wait);
160 		if (ret) {
161 			if (ret < 0)
162 				rc = ret;
163 			break;
164 		}
165 	}
166 	remove_wait_queue(sk_sleep(sk), &wait);
167 	return rc;
168 }
169 
170 int tls_push_sg(struct sock *sk,
171 		struct tls_context *ctx,
172 		struct scatterlist *sg,
173 		u16 first_offset,
174 		int flags)
175 {
176 	struct bio_vec bvec;
177 	struct msghdr msg = {
178 		.msg_flags = MSG_SPLICE_PAGES | flags,
179 	};
180 	int ret = 0;
181 	struct page *p;
182 	size_t size;
183 	int offset = first_offset;
184 
185 	size = sg->length - offset;
186 	offset += sg->offset;
187 
188 	ctx->splicing_pages = true;
189 	while (1) {
190 		/* is sending application-limited? */
191 		tcp_rate_check_app_limited(sk);
192 		p = sg_page(sg);
193 retry:
194 		bvec_set_page(&bvec, p, size, offset);
195 		iov_iter_bvec(&msg.msg_iter, ITER_SOURCE, &bvec, 1, size);
196 
197 		ret = tcp_sendmsg_locked(sk, &msg, size);
198 
199 		if (ret != size) {
200 			if (ret > 0) {
201 				offset += ret;
202 				size -= ret;
203 				goto retry;
204 			}
205 
206 			offset -= sg->offset;
207 			ctx->partially_sent_offset = offset;
208 			ctx->partially_sent_record = (void *)sg;
209 			ctx->splicing_pages = false;
210 			return ret;
211 		}
212 
213 		put_page(p);
214 		sk_mem_uncharge(sk, sg->length);
215 		sg = sg_next(sg);
216 		if (!sg)
217 			break;
218 
219 		offset = sg->offset;
220 		size = sg->length;
221 	}
222 
223 	ctx->splicing_pages = false;
224 
225 	return 0;
226 }
227 
228 static int tls_handle_open_record(struct sock *sk, int flags)
229 {
230 	struct tls_context *ctx = tls_get_ctx(sk);
231 
232 	if (tls_is_pending_open_record(ctx))
233 		return ctx->push_pending_record(sk, flags);
234 
235 	return 0;
236 }
237 
238 int tls_process_cmsg(struct sock *sk, struct msghdr *msg,
239 		     unsigned char *record_type)
240 {
241 	struct cmsghdr *cmsg;
242 	int rc = -EINVAL;
243 
244 	for_each_cmsghdr(cmsg, msg) {
245 		if (!CMSG_OK(msg, cmsg))
246 			return -EINVAL;
247 		if (cmsg->cmsg_level != SOL_TLS)
248 			continue;
249 
250 		switch (cmsg->cmsg_type) {
251 		case TLS_SET_RECORD_TYPE:
252 			if (cmsg->cmsg_len < CMSG_LEN(sizeof(*record_type)))
253 				return -EINVAL;
254 
255 			if (msg->msg_flags & MSG_MORE)
256 				return -EINVAL;
257 
258 			rc = tls_handle_open_record(sk, msg->msg_flags);
259 			if (rc)
260 				return rc;
261 
262 			*record_type = *(unsigned char *)CMSG_DATA(cmsg);
263 			rc = 0;
264 			break;
265 		default:
266 			return -EINVAL;
267 		}
268 	}
269 
270 	return rc;
271 }
272 
273 int tls_push_partial_record(struct sock *sk, struct tls_context *ctx,
274 			    int flags)
275 {
276 	struct scatterlist *sg;
277 	u16 offset;
278 
279 	sg = ctx->partially_sent_record;
280 	offset = ctx->partially_sent_offset;
281 
282 	ctx->partially_sent_record = NULL;
283 	return tls_push_sg(sk, ctx, sg, offset, flags);
284 }
285 
286 void tls_free_partial_record(struct sock *sk, struct tls_context *ctx)
287 {
288 	struct scatterlist *sg;
289 
290 	for (sg = ctx->partially_sent_record; sg; sg = sg_next(sg)) {
291 		put_page(sg_page(sg));
292 		sk_mem_uncharge(sk, sg->length);
293 	}
294 	ctx->partially_sent_record = NULL;
295 }
296 
297 static void tls_write_space(struct sock *sk)
298 {
299 	struct tls_context *ctx = tls_get_ctx(sk);
300 
301 	/* If splicing_pages call lower protocol write space handler
302 	 * to ensure we wake up any waiting operations there. For example
303 	 * if splicing pages where to call sk_wait_event.
304 	 */
305 	if (ctx->splicing_pages) {
306 		ctx->sk_write_space(sk);
307 		return;
308 	}
309 
310 #ifdef CONFIG_TLS_DEVICE
311 	if (ctx->tx_conf == TLS_HW)
312 		tls_device_write_space(sk, ctx);
313 	else
314 #endif
315 		tls_sw_write_space(sk, ctx);
316 
317 	ctx->sk_write_space(sk);
318 }
319 
320 /**
321  * tls_ctx_free() - free TLS ULP context
322  * @sk:  socket to with @ctx is attached
323  * @ctx: TLS context structure
324  *
325  * Free TLS context. If @sk is %NULL caller guarantees that the socket
326  * to which @ctx was attached has no outstanding references.
327  */
328 void tls_ctx_free(struct sock *sk, struct tls_context *ctx)
329 {
330 	if (!ctx)
331 		return;
332 
333 	memzero_explicit(&ctx->crypto_send, sizeof(ctx->crypto_send));
334 	memzero_explicit(&ctx->crypto_recv, sizeof(ctx->crypto_recv));
335 	mutex_destroy(&ctx->tx_lock);
336 
337 	if (sk)
338 		kfree_rcu(ctx, rcu);
339 	else
340 		kfree(ctx);
341 }
342 
343 static void tls_sk_proto_cleanup(struct sock *sk,
344 				 struct tls_context *ctx, long timeo)
345 {
346 	if (unlikely(sk->sk_write_pending) &&
347 	    !wait_on_pending_writer(sk, &timeo))
348 		tls_handle_open_record(sk, 0);
349 
350 	/* We need these for tls_sw_fallback handling of other packets */
351 	if (ctx->tx_conf == TLS_SW) {
352 		tls_sw_release_resources_tx(sk);
353 		TLS_DEC_STATS(sock_net(sk), LINUX_MIB_TLSCURRTXSW);
354 	} else if (ctx->tx_conf == TLS_HW) {
355 		tls_device_free_resources_tx(sk);
356 		TLS_DEC_STATS(sock_net(sk), LINUX_MIB_TLSCURRTXDEVICE);
357 	}
358 
359 	if (ctx->rx_conf == TLS_SW) {
360 		tls_sw_release_resources_rx(sk);
361 		TLS_DEC_STATS(sock_net(sk), LINUX_MIB_TLSCURRRXSW);
362 	} else if (ctx->rx_conf == TLS_HW) {
363 		tls_device_offload_cleanup_rx(sk);
364 		TLS_DEC_STATS(sock_net(sk), LINUX_MIB_TLSCURRRXDEVICE);
365 	}
366 }
367 
368 static void tls_sk_proto_close(struct sock *sk, long timeout)
369 {
370 	struct inet_connection_sock *icsk = inet_csk(sk);
371 	struct tls_context *ctx = tls_get_ctx(sk);
372 	long timeo = sock_sndtimeo(sk, 0);
373 	bool free_ctx;
374 
375 	if (ctx->tx_conf == TLS_SW)
376 		tls_sw_cancel_work_tx(ctx);
377 
378 	lock_sock(sk);
379 	free_ctx = ctx->tx_conf != TLS_HW && ctx->rx_conf != TLS_HW;
380 
381 	if (ctx->tx_conf != TLS_BASE || ctx->rx_conf != TLS_BASE)
382 		tls_sk_proto_cleanup(sk, ctx, timeo);
383 
384 	write_lock_bh(&sk->sk_callback_lock);
385 	if (free_ctx)
386 		rcu_assign_pointer(icsk->icsk_ulp_data, NULL);
387 	WRITE_ONCE(sk->sk_prot, ctx->sk_proto);
388 	if (sk->sk_write_space == tls_write_space)
389 		sk->sk_write_space = ctx->sk_write_space;
390 	write_unlock_bh(&sk->sk_callback_lock);
391 	release_sock(sk);
392 	if (ctx->tx_conf == TLS_SW)
393 		tls_sw_free_ctx_tx(ctx);
394 	if (ctx->rx_conf == TLS_SW || ctx->rx_conf == TLS_HW)
395 		tls_sw_strparser_done(ctx);
396 	if (ctx->rx_conf == TLS_SW)
397 		tls_sw_free_ctx_rx(ctx);
398 	ctx->sk_proto->close(sk, timeout);
399 
400 	if (free_ctx)
401 		tls_ctx_free(sk, ctx);
402 }
403 
404 static __poll_t tls_sk_poll(struct file *file, struct socket *sock,
405 			    struct poll_table_struct *wait)
406 {
407 	struct tls_sw_context_rx *ctx;
408 	struct tls_context *tls_ctx;
409 	struct sock *sk = sock->sk;
410 	struct sk_psock *psock;
411 	__poll_t mask = 0;
412 	u8 shutdown;
413 	int state;
414 
415 	mask = tcp_poll(file, sock, wait);
416 
417 	state = inet_sk_state_load(sk);
418 	shutdown = READ_ONCE(sk->sk_shutdown);
419 	if (unlikely(state != TCP_ESTABLISHED || shutdown & RCV_SHUTDOWN))
420 		return mask;
421 
422 	tls_ctx = tls_get_ctx(sk);
423 	ctx = tls_sw_ctx_rx(tls_ctx);
424 	psock = sk_psock_get(sk);
425 
426 	if (skb_queue_empty_lockless(&ctx->rx_list) &&
427 	    !tls_strp_msg_ready(ctx) &&
428 	    sk_psock_queue_empty(psock))
429 		mask &= ~(EPOLLIN | EPOLLRDNORM);
430 
431 	if (psock)
432 		sk_psock_put(sk, psock);
433 
434 	return mask;
435 }
436 
437 static int do_tls_getsockopt_conf(struct sock *sk, char __user *optval,
438 				  int __user *optlen, int tx)
439 {
440 	int rc = 0;
441 	const struct tls_cipher_desc *cipher_desc;
442 	struct tls_context *ctx = tls_get_ctx(sk);
443 	struct tls_crypto_info *crypto_info;
444 	struct cipher_context *cctx;
445 	int len;
446 
447 	if (get_user(len, optlen))
448 		return -EFAULT;
449 
450 	if (!optval || (len < sizeof(*crypto_info))) {
451 		rc = -EINVAL;
452 		goto out;
453 	}
454 
455 	if (!ctx) {
456 		rc = -EBUSY;
457 		goto out;
458 	}
459 
460 	/* get user crypto info */
461 	if (tx) {
462 		crypto_info = &ctx->crypto_send.info;
463 		cctx = &ctx->tx;
464 	} else {
465 		crypto_info = &ctx->crypto_recv.info;
466 		cctx = &ctx->rx;
467 	}
468 
469 	if (!TLS_CRYPTO_INFO_READY(crypto_info)) {
470 		rc = -EBUSY;
471 		goto out;
472 	}
473 
474 	if (len == sizeof(*crypto_info)) {
475 		if (copy_to_user(optval, crypto_info, sizeof(*crypto_info)))
476 			rc = -EFAULT;
477 		goto out;
478 	}
479 
480 	cipher_desc = get_cipher_desc(crypto_info->cipher_type);
481 	if (!cipher_desc || len != cipher_desc->crypto_info) {
482 		rc = -EINVAL;
483 		goto out;
484 	}
485 
486 	memcpy(crypto_info_iv(crypto_info, cipher_desc),
487 	       cctx->iv + cipher_desc->salt, cipher_desc->iv);
488 	memcpy(crypto_info_rec_seq(crypto_info, cipher_desc),
489 	       cctx->rec_seq, cipher_desc->rec_seq);
490 
491 	if (copy_to_user(optval, crypto_info, cipher_desc->crypto_info))
492 		rc = -EFAULT;
493 
494 out:
495 	return rc;
496 }
497 
498 static int do_tls_getsockopt_tx_zc(struct sock *sk, char __user *optval,
499 				   int __user *optlen)
500 {
501 	struct tls_context *ctx = tls_get_ctx(sk);
502 	unsigned int value;
503 	int len;
504 
505 	if (get_user(len, optlen))
506 		return -EFAULT;
507 
508 	if (len != sizeof(value))
509 		return -EINVAL;
510 
511 	value = ctx->zerocopy_sendfile;
512 	if (copy_to_user(optval, &value, sizeof(value)))
513 		return -EFAULT;
514 
515 	return 0;
516 }
517 
518 static int do_tls_getsockopt_no_pad(struct sock *sk, char __user *optval,
519 				    int __user *optlen)
520 {
521 	struct tls_context *ctx = tls_get_ctx(sk);
522 	int value, len;
523 
524 	if (ctx->prot_info.version != TLS_1_3_VERSION)
525 		return -EINVAL;
526 
527 	if (get_user(len, optlen))
528 		return -EFAULT;
529 	if (len < sizeof(value))
530 		return -EINVAL;
531 
532 	value = -EINVAL;
533 	if (ctx->rx_conf == TLS_SW || ctx->rx_conf == TLS_HW)
534 		value = ctx->rx_no_pad;
535 	if (value < 0)
536 		return value;
537 
538 	if (put_user(sizeof(value), optlen))
539 		return -EFAULT;
540 	if (copy_to_user(optval, &value, sizeof(value)))
541 		return -EFAULT;
542 
543 	return 0;
544 }
545 
546 static int do_tls_getsockopt(struct sock *sk, int optname,
547 			     char __user *optval, int __user *optlen)
548 {
549 	int rc = 0;
550 
551 	lock_sock(sk);
552 
553 	switch (optname) {
554 	case TLS_TX:
555 	case TLS_RX:
556 		rc = do_tls_getsockopt_conf(sk, optval, optlen,
557 					    optname == TLS_TX);
558 		break;
559 	case TLS_TX_ZEROCOPY_RO:
560 		rc = do_tls_getsockopt_tx_zc(sk, optval, optlen);
561 		break;
562 	case TLS_RX_EXPECT_NO_PAD:
563 		rc = do_tls_getsockopt_no_pad(sk, optval, optlen);
564 		break;
565 	default:
566 		rc = -ENOPROTOOPT;
567 		break;
568 	}
569 
570 	release_sock(sk);
571 
572 	return rc;
573 }
574 
575 static int tls_getsockopt(struct sock *sk, int level, int optname,
576 			  char __user *optval, int __user *optlen)
577 {
578 	struct tls_context *ctx = tls_get_ctx(sk);
579 
580 	if (level != SOL_TLS)
581 		return ctx->sk_proto->getsockopt(sk, level,
582 						 optname, optval, optlen);
583 
584 	return do_tls_getsockopt(sk, optname, optval, optlen);
585 }
586 
587 static int validate_crypto_info(const struct tls_crypto_info *crypto_info,
588 				const struct tls_crypto_info *alt_crypto_info)
589 {
590 	if (crypto_info->version != TLS_1_2_VERSION &&
591 	    crypto_info->version != TLS_1_3_VERSION)
592 		return -EINVAL;
593 
594 	switch (crypto_info->cipher_type) {
595 	case TLS_CIPHER_ARIA_GCM_128:
596 	case TLS_CIPHER_ARIA_GCM_256:
597 		if (crypto_info->version != TLS_1_2_VERSION)
598 			return -EINVAL;
599 		break;
600 	}
601 
602 	/* Ensure that TLS version and ciphers are same in both directions */
603 	if (TLS_CRYPTO_INFO_READY(alt_crypto_info)) {
604 		if (alt_crypto_info->version != crypto_info->version ||
605 		    alt_crypto_info->cipher_type != crypto_info->cipher_type)
606 			return -EINVAL;
607 	}
608 
609 	return 0;
610 }
611 
612 static int do_tls_setsockopt_conf(struct sock *sk, sockptr_t optval,
613 				  unsigned int optlen, int tx)
614 {
615 	struct tls_crypto_info *crypto_info;
616 	struct tls_crypto_info *alt_crypto_info;
617 	struct tls_context *ctx = tls_get_ctx(sk);
618 	const struct tls_cipher_desc *cipher_desc;
619 	union tls_crypto_context *crypto_ctx;
620 	int rc = 0;
621 	int conf;
622 
623 	if (sockptr_is_null(optval) || (optlen < sizeof(*crypto_info)))
624 		return -EINVAL;
625 
626 	if (tx) {
627 		crypto_ctx = &ctx->crypto_send;
628 		alt_crypto_info = &ctx->crypto_recv.info;
629 	} else {
630 		crypto_ctx = &ctx->crypto_recv;
631 		alt_crypto_info = &ctx->crypto_send.info;
632 	}
633 
634 	crypto_info = &crypto_ctx->info;
635 
636 	/* Currently we don't support set crypto info more than one time */
637 	if (TLS_CRYPTO_INFO_READY(crypto_info))
638 		return -EBUSY;
639 
640 	rc = copy_from_sockptr(crypto_info, optval, sizeof(*crypto_info));
641 	if (rc) {
642 		rc = -EFAULT;
643 		goto err_crypto_info;
644 	}
645 
646 	rc = validate_crypto_info(crypto_info, alt_crypto_info);
647 	if (rc)
648 		goto err_crypto_info;
649 
650 	cipher_desc = get_cipher_desc(crypto_info->cipher_type);
651 	if (!cipher_desc) {
652 		rc = -EINVAL;
653 		goto err_crypto_info;
654 	}
655 
656 	if (optlen != cipher_desc->crypto_info) {
657 		rc = -EINVAL;
658 		goto err_crypto_info;
659 	}
660 
661 	rc = copy_from_sockptr_offset(crypto_info + 1, optval,
662 				      sizeof(*crypto_info),
663 				      optlen - sizeof(*crypto_info));
664 	if (rc) {
665 		rc = -EFAULT;
666 		goto err_crypto_info;
667 	}
668 
669 	if (tx) {
670 		rc = tls_set_device_offload(sk);
671 		conf = TLS_HW;
672 		if (!rc) {
673 			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSTXDEVICE);
674 			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSCURRTXDEVICE);
675 		} else {
676 			rc = tls_set_sw_offload(sk, 1);
677 			if (rc)
678 				goto err_crypto_info;
679 			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSTXSW);
680 			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSCURRTXSW);
681 			conf = TLS_SW;
682 		}
683 	} else {
684 		rc = tls_set_device_offload_rx(sk, ctx);
685 		conf = TLS_HW;
686 		if (!rc) {
687 			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSRXDEVICE);
688 			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSCURRRXDEVICE);
689 		} else {
690 			rc = tls_set_sw_offload(sk, 0);
691 			if (rc)
692 				goto err_crypto_info;
693 			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSRXSW);
694 			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSCURRRXSW);
695 			conf = TLS_SW;
696 		}
697 		tls_sw_strparser_arm(sk, ctx);
698 	}
699 
700 	if (tx)
701 		ctx->tx_conf = conf;
702 	else
703 		ctx->rx_conf = conf;
704 	update_sk_prot(sk, ctx);
705 	if (tx) {
706 		ctx->sk_write_space = sk->sk_write_space;
707 		sk->sk_write_space = tls_write_space;
708 	} else {
709 		struct tls_sw_context_rx *rx_ctx = tls_sw_ctx_rx(ctx);
710 
711 		tls_strp_check_rcv(&rx_ctx->strp);
712 	}
713 	return 0;
714 
715 err_crypto_info:
716 	memzero_explicit(crypto_ctx, sizeof(*crypto_ctx));
717 	return rc;
718 }
719 
720 static int do_tls_setsockopt_tx_zc(struct sock *sk, sockptr_t optval,
721 				   unsigned int optlen)
722 {
723 	struct tls_context *ctx = tls_get_ctx(sk);
724 	unsigned int value;
725 
726 	if (sockptr_is_null(optval) || optlen != sizeof(value))
727 		return -EINVAL;
728 
729 	if (copy_from_sockptr(&value, optval, sizeof(value)))
730 		return -EFAULT;
731 
732 	if (value > 1)
733 		return -EINVAL;
734 
735 	ctx->zerocopy_sendfile = value;
736 
737 	return 0;
738 }
739 
740 static int do_tls_setsockopt_no_pad(struct sock *sk, sockptr_t optval,
741 				    unsigned int optlen)
742 {
743 	struct tls_context *ctx = tls_get_ctx(sk);
744 	u32 val;
745 	int rc;
746 
747 	if (ctx->prot_info.version != TLS_1_3_VERSION ||
748 	    sockptr_is_null(optval) || optlen < sizeof(val))
749 		return -EINVAL;
750 
751 	rc = copy_from_sockptr(&val, optval, sizeof(val));
752 	if (rc)
753 		return -EFAULT;
754 	if (val > 1)
755 		return -EINVAL;
756 	rc = check_zeroed_sockptr(optval, sizeof(val), optlen - sizeof(val));
757 	if (rc < 1)
758 		return rc == 0 ? -EINVAL : rc;
759 
760 	lock_sock(sk);
761 	rc = -EINVAL;
762 	if (ctx->rx_conf == TLS_SW || ctx->rx_conf == TLS_HW) {
763 		ctx->rx_no_pad = val;
764 		tls_update_rx_zc_capable(ctx);
765 		rc = 0;
766 	}
767 	release_sock(sk);
768 
769 	return rc;
770 }
771 
772 static int do_tls_setsockopt(struct sock *sk, int optname, sockptr_t optval,
773 			     unsigned int optlen)
774 {
775 	int rc = 0;
776 
777 	switch (optname) {
778 	case TLS_TX:
779 	case TLS_RX:
780 		lock_sock(sk);
781 		rc = do_tls_setsockopt_conf(sk, optval, optlen,
782 					    optname == TLS_TX);
783 		release_sock(sk);
784 		break;
785 	case TLS_TX_ZEROCOPY_RO:
786 		lock_sock(sk);
787 		rc = do_tls_setsockopt_tx_zc(sk, optval, optlen);
788 		release_sock(sk);
789 		break;
790 	case TLS_RX_EXPECT_NO_PAD:
791 		rc = do_tls_setsockopt_no_pad(sk, optval, optlen);
792 		break;
793 	default:
794 		rc = -ENOPROTOOPT;
795 		break;
796 	}
797 	return rc;
798 }
799 
800 static int tls_setsockopt(struct sock *sk, int level, int optname,
801 			  sockptr_t optval, unsigned int optlen)
802 {
803 	struct tls_context *ctx = tls_get_ctx(sk);
804 
805 	if (level != SOL_TLS)
806 		return ctx->sk_proto->setsockopt(sk, level, optname, optval,
807 						 optlen);
808 
809 	return do_tls_setsockopt(sk, optname, optval, optlen);
810 }
811 
812 struct tls_context *tls_ctx_create(struct sock *sk)
813 {
814 	struct inet_connection_sock *icsk = inet_csk(sk);
815 	struct tls_context *ctx;
816 
817 	ctx = kzalloc(sizeof(*ctx), GFP_ATOMIC);
818 	if (!ctx)
819 		return NULL;
820 
821 	mutex_init(&ctx->tx_lock);
822 	ctx->sk_proto = READ_ONCE(sk->sk_prot);
823 	ctx->sk = sk;
824 	/* Release semantic of rcu_assign_pointer() ensures that
825 	 * ctx->sk_proto is visible before changing sk->sk_prot in
826 	 * update_sk_prot(), and prevents reading uninitialized value in
827 	 * tls_{getsockopt, setsockopt}. Note that we do not need a
828 	 * read barrier in tls_{getsockopt,setsockopt} as there is an
829 	 * address dependency between sk->sk_proto->{getsockopt,setsockopt}
830 	 * and ctx->sk_proto.
831 	 */
832 	rcu_assign_pointer(icsk->icsk_ulp_data, ctx);
833 	return ctx;
834 }
835 
836 static void build_proto_ops(struct proto_ops ops[TLS_NUM_CONFIG][TLS_NUM_CONFIG],
837 			    const struct proto_ops *base)
838 {
839 	ops[TLS_BASE][TLS_BASE] = *base;
840 
841 	ops[TLS_SW  ][TLS_BASE] = ops[TLS_BASE][TLS_BASE];
842 	ops[TLS_SW  ][TLS_BASE].splice_eof	= tls_sw_splice_eof;
843 
844 	ops[TLS_BASE][TLS_SW  ] = ops[TLS_BASE][TLS_BASE];
845 	ops[TLS_BASE][TLS_SW  ].splice_read	= tls_sw_splice_read;
846 	ops[TLS_BASE][TLS_SW  ].poll		= tls_sk_poll;
847 	ops[TLS_BASE][TLS_SW  ].read_sock	= tls_sw_read_sock;
848 
849 	ops[TLS_SW  ][TLS_SW  ] = ops[TLS_SW  ][TLS_BASE];
850 	ops[TLS_SW  ][TLS_SW  ].splice_read	= tls_sw_splice_read;
851 	ops[TLS_SW  ][TLS_SW  ].poll		= tls_sk_poll;
852 	ops[TLS_SW  ][TLS_SW  ].read_sock	= tls_sw_read_sock;
853 
854 #ifdef CONFIG_TLS_DEVICE
855 	ops[TLS_HW  ][TLS_BASE] = ops[TLS_BASE][TLS_BASE];
856 
857 	ops[TLS_HW  ][TLS_SW  ] = ops[TLS_BASE][TLS_SW  ];
858 
859 	ops[TLS_BASE][TLS_HW  ] = ops[TLS_BASE][TLS_SW  ];
860 
861 	ops[TLS_SW  ][TLS_HW  ] = ops[TLS_SW  ][TLS_SW  ];
862 
863 	ops[TLS_HW  ][TLS_HW  ] = ops[TLS_HW  ][TLS_SW  ];
864 #endif
865 #ifdef CONFIG_TLS_TOE
866 	ops[TLS_HW_RECORD][TLS_HW_RECORD] = *base;
867 #endif
868 }
869 
870 static void tls_build_proto(struct sock *sk)
871 {
872 	int ip_ver = sk->sk_family == AF_INET6 ? TLSV6 : TLSV4;
873 	struct proto *prot = READ_ONCE(sk->sk_prot);
874 
875 	/* Build IPv6 TLS whenever the address of tcpv6 _prot changes */
876 	if (ip_ver == TLSV6 &&
877 	    unlikely(prot != smp_load_acquire(&saved_tcpv6_prot))) {
878 		mutex_lock(&tcpv6_prot_mutex);
879 		if (likely(prot != saved_tcpv6_prot)) {
880 			build_protos(tls_prots[TLSV6], prot);
881 			build_proto_ops(tls_proto_ops[TLSV6],
882 					sk->sk_socket->ops);
883 			smp_store_release(&saved_tcpv6_prot, prot);
884 		}
885 		mutex_unlock(&tcpv6_prot_mutex);
886 	}
887 
888 	if (ip_ver == TLSV4 &&
889 	    unlikely(prot != smp_load_acquire(&saved_tcpv4_prot))) {
890 		mutex_lock(&tcpv4_prot_mutex);
891 		if (likely(prot != saved_tcpv4_prot)) {
892 			build_protos(tls_prots[TLSV4], prot);
893 			build_proto_ops(tls_proto_ops[TLSV4],
894 					sk->sk_socket->ops);
895 			smp_store_release(&saved_tcpv4_prot, prot);
896 		}
897 		mutex_unlock(&tcpv4_prot_mutex);
898 	}
899 }
900 
901 static void build_protos(struct proto prot[TLS_NUM_CONFIG][TLS_NUM_CONFIG],
902 			 const struct proto *base)
903 {
904 	prot[TLS_BASE][TLS_BASE] = *base;
905 	prot[TLS_BASE][TLS_BASE].setsockopt	= tls_setsockopt;
906 	prot[TLS_BASE][TLS_BASE].getsockopt	= tls_getsockopt;
907 	prot[TLS_BASE][TLS_BASE].close		= tls_sk_proto_close;
908 
909 	prot[TLS_SW][TLS_BASE] = prot[TLS_BASE][TLS_BASE];
910 	prot[TLS_SW][TLS_BASE].sendmsg		= tls_sw_sendmsg;
911 	prot[TLS_SW][TLS_BASE].splice_eof	= tls_sw_splice_eof;
912 
913 	prot[TLS_BASE][TLS_SW] = prot[TLS_BASE][TLS_BASE];
914 	prot[TLS_BASE][TLS_SW].recvmsg		  = tls_sw_recvmsg;
915 	prot[TLS_BASE][TLS_SW].sock_is_readable   = tls_sw_sock_is_readable;
916 	prot[TLS_BASE][TLS_SW].close		  = tls_sk_proto_close;
917 
918 	prot[TLS_SW][TLS_SW] = prot[TLS_SW][TLS_BASE];
919 	prot[TLS_SW][TLS_SW].recvmsg		= tls_sw_recvmsg;
920 	prot[TLS_SW][TLS_SW].sock_is_readable   = tls_sw_sock_is_readable;
921 	prot[TLS_SW][TLS_SW].close		= tls_sk_proto_close;
922 
923 #ifdef CONFIG_TLS_DEVICE
924 	prot[TLS_HW][TLS_BASE] = prot[TLS_BASE][TLS_BASE];
925 	prot[TLS_HW][TLS_BASE].sendmsg		= tls_device_sendmsg;
926 	prot[TLS_HW][TLS_BASE].splice_eof	= tls_device_splice_eof;
927 
928 	prot[TLS_HW][TLS_SW] = prot[TLS_BASE][TLS_SW];
929 	prot[TLS_HW][TLS_SW].sendmsg		= tls_device_sendmsg;
930 	prot[TLS_HW][TLS_SW].splice_eof		= tls_device_splice_eof;
931 
932 	prot[TLS_BASE][TLS_HW] = prot[TLS_BASE][TLS_SW];
933 
934 	prot[TLS_SW][TLS_HW] = prot[TLS_SW][TLS_SW];
935 
936 	prot[TLS_HW][TLS_HW] = prot[TLS_HW][TLS_SW];
937 #endif
938 #ifdef CONFIG_TLS_TOE
939 	prot[TLS_HW_RECORD][TLS_HW_RECORD] = *base;
940 	prot[TLS_HW_RECORD][TLS_HW_RECORD].hash		= tls_toe_hash;
941 	prot[TLS_HW_RECORD][TLS_HW_RECORD].unhash	= tls_toe_unhash;
942 #endif
943 }
944 
945 static int tls_init(struct sock *sk)
946 {
947 	struct tls_context *ctx;
948 	int rc = 0;
949 
950 	tls_build_proto(sk);
951 
952 #ifdef CONFIG_TLS_TOE
953 	if (tls_toe_bypass(sk))
954 		return 0;
955 #endif
956 
957 	/* The TLS ulp is currently supported only for TCP sockets
958 	 * in ESTABLISHED state.
959 	 * Supporting sockets in LISTEN state will require us
960 	 * to modify the accept implementation to clone rather then
961 	 * share the ulp context.
962 	 */
963 	if (sk->sk_state != TCP_ESTABLISHED)
964 		return -ENOTCONN;
965 
966 	/* allocate tls context */
967 	write_lock_bh(&sk->sk_callback_lock);
968 	ctx = tls_ctx_create(sk);
969 	if (!ctx) {
970 		rc = -ENOMEM;
971 		goto out;
972 	}
973 
974 	ctx->tx_conf = TLS_BASE;
975 	ctx->rx_conf = TLS_BASE;
976 	update_sk_prot(sk, ctx);
977 out:
978 	write_unlock_bh(&sk->sk_callback_lock);
979 	return rc;
980 }
981 
982 static void tls_update(struct sock *sk, struct proto *p,
983 		       void (*write_space)(struct sock *sk))
984 {
985 	struct tls_context *ctx;
986 
987 	WARN_ON_ONCE(sk->sk_prot == p);
988 
989 	ctx = tls_get_ctx(sk);
990 	if (likely(ctx)) {
991 		ctx->sk_write_space = write_space;
992 		ctx->sk_proto = p;
993 	} else {
994 		/* Pairs with lockless read in sk_clone_lock(). */
995 		WRITE_ONCE(sk->sk_prot, p);
996 		sk->sk_write_space = write_space;
997 	}
998 }
999 
1000 static u16 tls_user_config(struct tls_context *ctx, bool tx)
1001 {
1002 	u16 config = tx ? ctx->tx_conf : ctx->rx_conf;
1003 
1004 	switch (config) {
1005 	case TLS_BASE:
1006 		return TLS_CONF_BASE;
1007 	case TLS_SW:
1008 		return TLS_CONF_SW;
1009 	case TLS_HW:
1010 		return TLS_CONF_HW;
1011 	case TLS_HW_RECORD:
1012 		return TLS_CONF_HW_RECORD;
1013 	}
1014 	return 0;
1015 }
1016 
1017 static int tls_get_info(struct sock *sk, struct sk_buff *skb)
1018 {
1019 	u16 version, cipher_type;
1020 	struct tls_context *ctx;
1021 	struct nlattr *start;
1022 	int err;
1023 
1024 	start = nla_nest_start_noflag(skb, INET_ULP_INFO_TLS);
1025 	if (!start)
1026 		return -EMSGSIZE;
1027 
1028 	rcu_read_lock();
1029 	ctx = rcu_dereference(inet_csk(sk)->icsk_ulp_data);
1030 	if (!ctx) {
1031 		err = 0;
1032 		goto nla_failure;
1033 	}
1034 	version = ctx->prot_info.version;
1035 	if (version) {
1036 		err = nla_put_u16(skb, TLS_INFO_VERSION, version);
1037 		if (err)
1038 			goto nla_failure;
1039 	}
1040 	cipher_type = ctx->prot_info.cipher_type;
1041 	if (cipher_type) {
1042 		err = nla_put_u16(skb, TLS_INFO_CIPHER, cipher_type);
1043 		if (err)
1044 			goto nla_failure;
1045 	}
1046 	err = nla_put_u16(skb, TLS_INFO_TXCONF, tls_user_config(ctx, true));
1047 	if (err)
1048 		goto nla_failure;
1049 
1050 	err = nla_put_u16(skb, TLS_INFO_RXCONF, tls_user_config(ctx, false));
1051 	if (err)
1052 		goto nla_failure;
1053 
1054 	if (ctx->tx_conf == TLS_HW && ctx->zerocopy_sendfile) {
1055 		err = nla_put_flag(skb, TLS_INFO_ZC_RO_TX);
1056 		if (err)
1057 			goto nla_failure;
1058 	}
1059 	if (ctx->rx_no_pad) {
1060 		err = nla_put_flag(skb, TLS_INFO_RX_NO_PAD);
1061 		if (err)
1062 			goto nla_failure;
1063 	}
1064 
1065 	rcu_read_unlock();
1066 	nla_nest_end(skb, start);
1067 	return 0;
1068 
1069 nla_failure:
1070 	rcu_read_unlock();
1071 	nla_nest_cancel(skb, start);
1072 	return err;
1073 }
1074 
1075 static size_t tls_get_info_size(const struct sock *sk)
1076 {
1077 	size_t size = 0;
1078 
1079 	size += nla_total_size(0) +		/* INET_ULP_INFO_TLS */
1080 		nla_total_size(sizeof(u16)) +	/* TLS_INFO_VERSION */
1081 		nla_total_size(sizeof(u16)) +	/* TLS_INFO_CIPHER */
1082 		nla_total_size(sizeof(u16)) +	/* TLS_INFO_RXCONF */
1083 		nla_total_size(sizeof(u16)) +	/* TLS_INFO_TXCONF */
1084 		nla_total_size(0) +		/* TLS_INFO_ZC_RO_TX */
1085 		nla_total_size(0) +		/* TLS_INFO_RX_NO_PAD */
1086 		0;
1087 
1088 	return size;
1089 }
1090 
1091 static int __net_init tls_init_net(struct net *net)
1092 {
1093 	int err;
1094 
1095 	net->mib.tls_statistics = alloc_percpu(struct linux_tls_mib);
1096 	if (!net->mib.tls_statistics)
1097 		return -ENOMEM;
1098 
1099 	err = tls_proc_init(net);
1100 	if (err)
1101 		goto err_free_stats;
1102 
1103 	return 0;
1104 err_free_stats:
1105 	free_percpu(net->mib.tls_statistics);
1106 	return err;
1107 }
1108 
1109 static void __net_exit tls_exit_net(struct net *net)
1110 {
1111 	tls_proc_fini(net);
1112 	free_percpu(net->mib.tls_statistics);
1113 }
1114 
1115 static struct pernet_operations tls_proc_ops = {
1116 	.init = tls_init_net,
1117 	.exit = tls_exit_net,
1118 };
1119 
1120 static struct tcp_ulp_ops tcp_tls_ulp_ops __read_mostly = {
1121 	.name			= "tls",
1122 	.owner			= THIS_MODULE,
1123 	.init			= tls_init,
1124 	.update			= tls_update,
1125 	.get_info		= tls_get_info,
1126 	.get_info_size		= tls_get_info_size,
1127 };
1128 
1129 static int __init tls_register(void)
1130 {
1131 	int err;
1132 
1133 	err = register_pernet_subsys(&tls_proc_ops);
1134 	if (err)
1135 		return err;
1136 
1137 	err = tls_strp_dev_init();
1138 	if (err)
1139 		goto err_pernet;
1140 
1141 	err = tls_device_init();
1142 	if (err)
1143 		goto err_strp;
1144 
1145 	tcp_register_ulp(&tcp_tls_ulp_ops);
1146 
1147 	return 0;
1148 err_strp:
1149 	tls_strp_dev_exit();
1150 err_pernet:
1151 	unregister_pernet_subsys(&tls_proc_ops);
1152 	return err;
1153 }
1154 
1155 static void __exit tls_unregister(void)
1156 {
1157 	tcp_unregister_ulp(&tcp_tls_ulp_ops);
1158 	tls_strp_dev_exit();
1159 	tls_device_cleanup();
1160 	unregister_pernet_subsys(&tls_proc_ops);
1161 }
1162 
1163 module_init(tls_register);
1164 module_exit(tls_unregister);
1165