xref: /linux/net/tls/tls_main.c (revision ab52c59103002b49f2455371e4b9c56ba3ef1781)
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 	int rc = 0;
620 	int conf;
621 
622 	if (sockptr_is_null(optval) || (optlen < sizeof(*crypto_info)))
623 		return -EINVAL;
624 
625 	if (tx) {
626 		crypto_info = &ctx->crypto_send.info;
627 		alt_crypto_info = &ctx->crypto_recv.info;
628 	} else {
629 		crypto_info = &ctx->crypto_recv.info;
630 		alt_crypto_info = &ctx->crypto_send.info;
631 	}
632 
633 	/* Currently we don't support set crypto info more than one time */
634 	if (TLS_CRYPTO_INFO_READY(crypto_info))
635 		return -EBUSY;
636 
637 	rc = copy_from_sockptr(crypto_info, optval, sizeof(*crypto_info));
638 	if (rc) {
639 		rc = -EFAULT;
640 		goto err_crypto_info;
641 	}
642 
643 	rc = validate_crypto_info(crypto_info, alt_crypto_info);
644 	if (rc)
645 		goto err_crypto_info;
646 
647 	cipher_desc = get_cipher_desc(crypto_info->cipher_type);
648 	if (!cipher_desc) {
649 		rc = -EINVAL;
650 		goto err_crypto_info;
651 	}
652 
653 	if (optlen != cipher_desc->crypto_info) {
654 		rc = -EINVAL;
655 		goto err_crypto_info;
656 	}
657 
658 	rc = copy_from_sockptr_offset(crypto_info + 1, optval,
659 				      sizeof(*crypto_info),
660 				      optlen - sizeof(*crypto_info));
661 	if (rc) {
662 		rc = -EFAULT;
663 		goto err_crypto_info;
664 	}
665 
666 	if (tx) {
667 		rc = tls_set_device_offload(sk);
668 		conf = TLS_HW;
669 		if (!rc) {
670 			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSTXDEVICE);
671 			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSCURRTXDEVICE);
672 		} else {
673 			rc = tls_set_sw_offload(sk, 1);
674 			if (rc)
675 				goto err_crypto_info;
676 			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSTXSW);
677 			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSCURRTXSW);
678 			conf = TLS_SW;
679 		}
680 	} else {
681 		rc = tls_set_device_offload_rx(sk, ctx);
682 		conf = TLS_HW;
683 		if (!rc) {
684 			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSRXDEVICE);
685 			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSCURRRXDEVICE);
686 		} else {
687 			rc = tls_set_sw_offload(sk, 0);
688 			if (rc)
689 				goto err_crypto_info;
690 			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSRXSW);
691 			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSCURRRXSW);
692 			conf = TLS_SW;
693 		}
694 		tls_sw_strparser_arm(sk, ctx);
695 	}
696 
697 	if (tx)
698 		ctx->tx_conf = conf;
699 	else
700 		ctx->rx_conf = conf;
701 	update_sk_prot(sk, ctx);
702 	if (tx) {
703 		ctx->sk_write_space = sk->sk_write_space;
704 		sk->sk_write_space = tls_write_space;
705 	} else {
706 		struct tls_sw_context_rx *rx_ctx = tls_sw_ctx_rx(ctx);
707 
708 		tls_strp_check_rcv(&rx_ctx->strp);
709 	}
710 	return 0;
711 
712 err_crypto_info:
713 	memzero_explicit(crypto_info, sizeof(union tls_crypto_context));
714 	return rc;
715 }
716 
717 static int do_tls_setsockopt_tx_zc(struct sock *sk, sockptr_t optval,
718 				   unsigned int optlen)
719 {
720 	struct tls_context *ctx = tls_get_ctx(sk);
721 	unsigned int value;
722 
723 	if (sockptr_is_null(optval) || optlen != sizeof(value))
724 		return -EINVAL;
725 
726 	if (copy_from_sockptr(&value, optval, sizeof(value)))
727 		return -EFAULT;
728 
729 	if (value > 1)
730 		return -EINVAL;
731 
732 	ctx->zerocopy_sendfile = value;
733 
734 	return 0;
735 }
736 
737 static int do_tls_setsockopt_no_pad(struct sock *sk, sockptr_t optval,
738 				    unsigned int optlen)
739 {
740 	struct tls_context *ctx = tls_get_ctx(sk);
741 	u32 val;
742 	int rc;
743 
744 	if (ctx->prot_info.version != TLS_1_3_VERSION ||
745 	    sockptr_is_null(optval) || optlen < sizeof(val))
746 		return -EINVAL;
747 
748 	rc = copy_from_sockptr(&val, optval, sizeof(val));
749 	if (rc)
750 		return -EFAULT;
751 	if (val > 1)
752 		return -EINVAL;
753 	rc = check_zeroed_sockptr(optval, sizeof(val), optlen - sizeof(val));
754 	if (rc < 1)
755 		return rc == 0 ? -EINVAL : rc;
756 
757 	lock_sock(sk);
758 	rc = -EINVAL;
759 	if (ctx->rx_conf == TLS_SW || ctx->rx_conf == TLS_HW) {
760 		ctx->rx_no_pad = val;
761 		tls_update_rx_zc_capable(ctx);
762 		rc = 0;
763 	}
764 	release_sock(sk);
765 
766 	return rc;
767 }
768 
769 static int do_tls_setsockopt(struct sock *sk, int optname, sockptr_t optval,
770 			     unsigned int optlen)
771 {
772 	int rc = 0;
773 
774 	switch (optname) {
775 	case TLS_TX:
776 	case TLS_RX:
777 		lock_sock(sk);
778 		rc = do_tls_setsockopt_conf(sk, optval, optlen,
779 					    optname == TLS_TX);
780 		release_sock(sk);
781 		break;
782 	case TLS_TX_ZEROCOPY_RO:
783 		lock_sock(sk);
784 		rc = do_tls_setsockopt_tx_zc(sk, optval, optlen);
785 		release_sock(sk);
786 		break;
787 	case TLS_RX_EXPECT_NO_PAD:
788 		rc = do_tls_setsockopt_no_pad(sk, optval, optlen);
789 		break;
790 	default:
791 		rc = -ENOPROTOOPT;
792 		break;
793 	}
794 	return rc;
795 }
796 
797 static int tls_setsockopt(struct sock *sk, int level, int optname,
798 			  sockptr_t optval, unsigned int optlen)
799 {
800 	struct tls_context *ctx = tls_get_ctx(sk);
801 
802 	if (level != SOL_TLS)
803 		return ctx->sk_proto->setsockopt(sk, level, optname, optval,
804 						 optlen);
805 
806 	return do_tls_setsockopt(sk, optname, optval, optlen);
807 }
808 
809 struct tls_context *tls_ctx_create(struct sock *sk)
810 {
811 	struct inet_connection_sock *icsk = inet_csk(sk);
812 	struct tls_context *ctx;
813 
814 	ctx = kzalloc(sizeof(*ctx), GFP_ATOMIC);
815 	if (!ctx)
816 		return NULL;
817 
818 	mutex_init(&ctx->tx_lock);
819 	ctx->sk_proto = READ_ONCE(sk->sk_prot);
820 	ctx->sk = sk;
821 	/* Release semantic of rcu_assign_pointer() ensures that
822 	 * ctx->sk_proto is visible before changing sk->sk_prot in
823 	 * update_sk_prot(), and prevents reading uninitialized value in
824 	 * tls_{getsockopt, setsockopt}. Note that we do not need a
825 	 * read barrier in tls_{getsockopt,setsockopt} as there is an
826 	 * address dependency between sk->sk_proto->{getsockopt,setsockopt}
827 	 * and ctx->sk_proto.
828 	 */
829 	rcu_assign_pointer(icsk->icsk_ulp_data, ctx);
830 	return ctx;
831 }
832 
833 static void build_proto_ops(struct proto_ops ops[TLS_NUM_CONFIG][TLS_NUM_CONFIG],
834 			    const struct proto_ops *base)
835 {
836 	ops[TLS_BASE][TLS_BASE] = *base;
837 
838 	ops[TLS_SW  ][TLS_BASE] = ops[TLS_BASE][TLS_BASE];
839 	ops[TLS_SW  ][TLS_BASE].splice_eof	= tls_sw_splice_eof;
840 
841 	ops[TLS_BASE][TLS_SW  ] = ops[TLS_BASE][TLS_BASE];
842 	ops[TLS_BASE][TLS_SW  ].splice_read	= tls_sw_splice_read;
843 	ops[TLS_BASE][TLS_SW  ].poll		= tls_sk_poll;
844 	ops[TLS_BASE][TLS_SW  ].read_sock	= tls_sw_read_sock;
845 
846 	ops[TLS_SW  ][TLS_SW  ] = ops[TLS_SW  ][TLS_BASE];
847 	ops[TLS_SW  ][TLS_SW  ].splice_read	= tls_sw_splice_read;
848 	ops[TLS_SW  ][TLS_SW  ].poll		= tls_sk_poll;
849 	ops[TLS_SW  ][TLS_SW  ].read_sock	= tls_sw_read_sock;
850 
851 #ifdef CONFIG_TLS_DEVICE
852 	ops[TLS_HW  ][TLS_BASE] = ops[TLS_BASE][TLS_BASE];
853 
854 	ops[TLS_HW  ][TLS_SW  ] = ops[TLS_BASE][TLS_SW  ];
855 
856 	ops[TLS_BASE][TLS_HW  ] = ops[TLS_BASE][TLS_SW  ];
857 
858 	ops[TLS_SW  ][TLS_HW  ] = ops[TLS_SW  ][TLS_SW  ];
859 
860 	ops[TLS_HW  ][TLS_HW  ] = ops[TLS_HW  ][TLS_SW  ];
861 #endif
862 #ifdef CONFIG_TLS_TOE
863 	ops[TLS_HW_RECORD][TLS_HW_RECORD] = *base;
864 #endif
865 }
866 
867 static void tls_build_proto(struct sock *sk)
868 {
869 	int ip_ver = sk->sk_family == AF_INET6 ? TLSV6 : TLSV4;
870 	struct proto *prot = READ_ONCE(sk->sk_prot);
871 
872 	/* Build IPv6 TLS whenever the address of tcpv6 _prot changes */
873 	if (ip_ver == TLSV6 &&
874 	    unlikely(prot != smp_load_acquire(&saved_tcpv6_prot))) {
875 		mutex_lock(&tcpv6_prot_mutex);
876 		if (likely(prot != saved_tcpv6_prot)) {
877 			build_protos(tls_prots[TLSV6], prot);
878 			build_proto_ops(tls_proto_ops[TLSV6],
879 					sk->sk_socket->ops);
880 			smp_store_release(&saved_tcpv6_prot, prot);
881 		}
882 		mutex_unlock(&tcpv6_prot_mutex);
883 	}
884 
885 	if (ip_ver == TLSV4 &&
886 	    unlikely(prot != smp_load_acquire(&saved_tcpv4_prot))) {
887 		mutex_lock(&tcpv4_prot_mutex);
888 		if (likely(prot != saved_tcpv4_prot)) {
889 			build_protos(tls_prots[TLSV4], prot);
890 			build_proto_ops(tls_proto_ops[TLSV4],
891 					sk->sk_socket->ops);
892 			smp_store_release(&saved_tcpv4_prot, prot);
893 		}
894 		mutex_unlock(&tcpv4_prot_mutex);
895 	}
896 }
897 
898 static void build_protos(struct proto prot[TLS_NUM_CONFIG][TLS_NUM_CONFIG],
899 			 const struct proto *base)
900 {
901 	prot[TLS_BASE][TLS_BASE] = *base;
902 	prot[TLS_BASE][TLS_BASE].setsockopt	= tls_setsockopt;
903 	prot[TLS_BASE][TLS_BASE].getsockopt	= tls_getsockopt;
904 	prot[TLS_BASE][TLS_BASE].close		= tls_sk_proto_close;
905 
906 	prot[TLS_SW][TLS_BASE] = prot[TLS_BASE][TLS_BASE];
907 	prot[TLS_SW][TLS_BASE].sendmsg		= tls_sw_sendmsg;
908 	prot[TLS_SW][TLS_BASE].splice_eof	= tls_sw_splice_eof;
909 
910 	prot[TLS_BASE][TLS_SW] = prot[TLS_BASE][TLS_BASE];
911 	prot[TLS_BASE][TLS_SW].recvmsg		  = tls_sw_recvmsg;
912 	prot[TLS_BASE][TLS_SW].sock_is_readable   = tls_sw_sock_is_readable;
913 	prot[TLS_BASE][TLS_SW].close		  = tls_sk_proto_close;
914 
915 	prot[TLS_SW][TLS_SW] = prot[TLS_SW][TLS_BASE];
916 	prot[TLS_SW][TLS_SW].recvmsg		= tls_sw_recvmsg;
917 	prot[TLS_SW][TLS_SW].sock_is_readable   = tls_sw_sock_is_readable;
918 	prot[TLS_SW][TLS_SW].close		= tls_sk_proto_close;
919 
920 #ifdef CONFIG_TLS_DEVICE
921 	prot[TLS_HW][TLS_BASE] = prot[TLS_BASE][TLS_BASE];
922 	prot[TLS_HW][TLS_BASE].sendmsg		= tls_device_sendmsg;
923 	prot[TLS_HW][TLS_BASE].splice_eof	= tls_device_splice_eof;
924 
925 	prot[TLS_HW][TLS_SW] = prot[TLS_BASE][TLS_SW];
926 	prot[TLS_HW][TLS_SW].sendmsg		= tls_device_sendmsg;
927 	prot[TLS_HW][TLS_SW].splice_eof		= tls_device_splice_eof;
928 
929 	prot[TLS_BASE][TLS_HW] = prot[TLS_BASE][TLS_SW];
930 
931 	prot[TLS_SW][TLS_HW] = prot[TLS_SW][TLS_SW];
932 
933 	prot[TLS_HW][TLS_HW] = prot[TLS_HW][TLS_SW];
934 #endif
935 #ifdef CONFIG_TLS_TOE
936 	prot[TLS_HW_RECORD][TLS_HW_RECORD] = *base;
937 	prot[TLS_HW_RECORD][TLS_HW_RECORD].hash		= tls_toe_hash;
938 	prot[TLS_HW_RECORD][TLS_HW_RECORD].unhash	= tls_toe_unhash;
939 #endif
940 }
941 
942 static int tls_init(struct sock *sk)
943 {
944 	struct tls_context *ctx;
945 	int rc = 0;
946 
947 	tls_build_proto(sk);
948 
949 #ifdef CONFIG_TLS_TOE
950 	if (tls_toe_bypass(sk))
951 		return 0;
952 #endif
953 
954 	/* The TLS ulp is currently supported only for TCP sockets
955 	 * in ESTABLISHED state.
956 	 * Supporting sockets in LISTEN state will require us
957 	 * to modify the accept implementation to clone rather then
958 	 * share the ulp context.
959 	 */
960 	if (sk->sk_state != TCP_ESTABLISHED)
961 		return -ENOTCONN;
962 
963 	/* allocate tls context */
964 	write_lock_bh(&sk->sk_callback_lock);
965 	ctx = tls_ctx_create(sk);
966 	if (!ctx) {
967 		rc = -ENOMEM;
968 		goto out;
969 	}
970 
971 	ctx->tx_conf = TLS_BASE;
972 	ctx->rx_conf = TLS_BASE;
973 	update_sk_prot(sk, ctx);
974 out:
975 	write_unlock_bh(&sk->sk_callback_lock);
976 	return rc;
977 }
978 
979 static void tls_update(struct sock *sk, struct proto *p,
980 		       void (*write_space)(struct sock *sk))
981 {
982 	struct tls_context *ctx;
983 
984 	WARN_ON_ONCE(sk->sk_prot == p);
985 
986 	ctx = tls_get_ctx(sk);
987 	if (likely(ctx)) {
988 		ctx->sk_write_space = write_space;
989 		ctx->sk_proto = p;
990 	} else {
991 		/* Pairs with lockless read in sk_clone_lock(). */
992 		WRITE_ONCE(sk->sk_prot, p);
993 		sk->sk_write_space = write_space;
994 	}
995 }
996 
997 static u16 tls_user_config(struct tls_context *ctx, bool tx)
998 {
999 	u16 config = tx ? ctx->tx_conf : ctx->rx_conf;
1000 
1001 	switch (config) {
1002 	case TLS_BASE:
1003 		return TLS_CONF_BASE;
1004 	case TLS_SW:
1005 		return TLS_CONF_SW;
1006 	case TLS_HW:
1007 		return TLS_CONF_HW;
1008 	case TLS_HW_RECORD:
1009 		return TLS_CONF_HW_RECORD;
1010 	}
1011 	return 0;
1012 }
1013 
1014 static int tls_get_info(struct sock *sk, struct sk_buff *skb)
1015 {
1016 	u16 version, cipher_type;
1017 	struct tls_context *ctx;
1018 	struct nlattr *start;
1019 	int err;
1020 
1021 	start = nla_nest_start_noflag(skb, INET_ULP_INFO_TLS);
1022 	if (!start)
1023 		return -EMSGSIZE;
1024 
1025 	rcu_read_lock();
1026 	ctx = rcu_dereference(inet_csk(sk)->icsk_ulp_data);
1027 	if (!ctx) {
1028 		err = 0;
1029 		goto nla_failure;
1030 	}
1031 	version = ctx->prot_info.version;
1032 	if (version) {
1033 		err = nla_put_u16(skb, TLS_INFO_VERSION, version);
1034 		if (err)
1035 			goto nla_failure;
1036 	}
1037 	cipher_type = ctx->prot_info.cipher_type;
1038 	if (cipher_type) {
1039 		err = nla_put_u16(skb, TLS_INFO_CIPHER, cipher_type);
1040 		if (err)
1041 			goto nla_failure;
1042 	}
1043 	err = nla_put_u16(skb, TLS_INFO_TXCONF, tls_user_config(ctx, true));
1044 	if (err)
1045 		goto nla_failure;
1046 
1047 	err = nla_put_u16(skb, TLS_INFO_RXCONF, tls_user_config(ctx, false));
1048 	if (err)
1049 		goto nla_failure;
1050 
1051 	if (ctx->tx_conf == TLS_HW && ctx->zerocopy_sendfile) {
1052 		err = nla_put_flag(skb, TLS_INFO_ZC_RO_TX);
1053 		if (err)
1054 			goto nla_failure;
1055 	}
1056 	if (ctx->rx_no_pad) {
1057 		err = nla_put_flag(skb, TLS_INFO_RX_NO_PAD);
1058 		if (err)
1059 			goto nla_failure;
1060 	}
1061 
1062 	rcu_read_unlock();
1063 	nla_nest_end(skb, start);
1064 	return 0;
1065 
1066 nla_failure:
1067 	rcu_read_unlock();
1068 	nla_nest_cancel(skb, start);
1069 	return err;
1070 }
1071 
1072 static size_t tls_get_info_size(const struct sock *sk)
1073 {
1074 	size_t size = 0;
1075 
1076 	size += nla_total_size(0) +		/* INET_ULP_INFO_TLS */
1077 		nla_total_size(sizeof(u16)) +	/* TLS_INFO_VERSION */
1078 		nla_total_size(sizeof(u16)) +	/* TLS_INFO_CIPHER */
1079 		nla_total_size(sizeof(u16)) +	/* TLS_INFO_RXCONF */
1080 		nla_total_size(sizeof(u16)) +	/* TLS_INFO_TXCONF */
1081 		nla_total_size(0) +		/* TLS_INFO_ZC_RO_TX */
1082 		nla_total_size(0) +		/* TLS_INFO_RX_NO_PAD */
1083 		0;
1084 
1085 	return size;
1086 }
1087 
1088 static int __net_init tls_init_net(struct net *net)
1089 {
1090 	int err;
1091 
1092 	net->mib.tls_statistics = alloc_percpu(struct linux_tls_mib);
1093 	if (!net->mib.tls_statistics)
1094 		return -ENOMEM;
1095 
1096 	err = tls_proc_init(net);
1097 	if (err)
1098 		goto err_free_stats;
1099 
1100 	return 0;
1101 err_free_stats:
1102 	free_percpu(net->mib.tls_statistics);
1103 	return err;
1104 }
1105 
1106 static void __net_exit tls_exit_net(struct net *net)
1107 {
1108 	tls_proc_fini(net);
1109 	free_percpu(net->mib.tls_statistics);
1110 }
1111 
1112 static struct pernet_operations tls_proc_ops = {
1113 	.init = tls_init_net,
1114 	.exit = tls_exit_net,
1115 };
1116 
1117 static struct tcp_ulp_ops tcp_tls_ulp_ops __read_mostly = {
1118 	.name			= "tls",
1119 	.owner			= THIS_MODULE,
1120 	.init			= tls_init,
1121 	.update			= tls_update,
1122 	.get_info		= tls_get_info,
1123 	.get_info_size		= tls_get_info_size,
1124 };
1125 
1126 static int __init tls_register(void)
1127 {
1128 	int err;
1129 
1130 	err = register_pernet_subsys(&tls_proc_ops);
1131 	if (err)
1132 		return err;
1133 
1134 	err = tls_strp_dev_init();
1135 	if (err)
1136 		goto err_pernet;
1137 
1138 	err = tls_device_init();
1139 	if (err)
1140 		goto err_strp;
1141 
1142 	tcp_register_ulp(&tcp_tls_ulp_ops);
1143 
1144 	return 0;
1145 err_strp:
1146 	tls_strp_dev_exit();
1147 err_pernet:
1148 	unregister_pernet_subsys(&tls_proc_ops);
1149 	return err;
1150 }
1151 
1152 static void __exit tls_unregister(void)
1153 {
1154 	tcp_unregister_ulp(&tcp_tls_ulp_ops);
1155 	tls_strp_dev_exit();
1156 	tls_device_cleanup();
1157 	unregister_pernet_subsys(&tls_proc_ops);
1158 }
1159 
1160 module_init(tls_register);
1161 module_exit(tls_unregister);
1162