xref: /linux/net/tls/tls_sw.c (revision a4a755c422242c27cb0f7900ac00cf33ac17b1ce)
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  * Copyright (c) 2016-2017, Lance Chao <lancerchao@fb.com>. All rights reserved.
5  * Copyright (c) 2016, Fridolin Pokorny <fridolin.pokorny@gmail.com>. All rights reserved.
6  * Copyright (c) 2016, Nikos Mavrogiannopoulos <nmav@gnutls.org>. All rights reserved.
7  * Copyright (c) 2018, Covalent IO, Inc. http://covalent.io
8  *
9  * This software is available to you under a choice of one of two
10  * licenses.  You may choose to be licensed under the terms of the GNU
11  * General Public License (GPL) Version 2, available from the file
12  * COPYING in the main directory of this source tree, or the
13  * OpenIB.org BSD license below:
14  *
15  *     Redistribution and use in source and binary forms, with or
16  *     without modification, are permitted provided that the following
17  *     conditions are met:
18  *
19  *      - Redistributions of source code must retain the above
20  *        copyright notice, this list of conditions and the following
21  *        disclaimer.
22  *
23  *      - Redistributions in binary form must reproduce the above
24  *        copyright notice, this list of conditions and the following
25  *        disclaimer in the documentation and/or other materials
26  *        provided with the distribution.
27  *
28  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
29  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
30  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
31  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
32  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
33  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
34  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
35  * SOFTWARE.
36  */
37 
38 #include <linux/bug.h>
39 #include <linux/sched/signal.h>
40 #include <linux/module.h>
41 #include <linux/kernel.h>
42 #include <linux/splice.h>
43 #include <crypto/aead.h>
44 
45 #include <net/strparser.h>
46 #include <net/tls.h>
47 #include <trace/events/sock.h>
48 
49 #include "tls.h"
50 
51 struct tls_decrypt_arg {
52 	struct_group(inargs,
53 	bool zc;
54 	bool async;
55 	bool async_done;
56 	u8 tail;
57 	);
58 
59 	struct sk_buff *skb;
60 };
61 
62 struct tls_decrypt_ctx {
63 	struct sock *sk;
64 	u8 iv[TLS_MAX_IV_SIZE];
65 	u8 aad[TLS_MAX_AAD_SIZE];
66 	u8 tail;
67 	bool free_sgout;
68 	struct scatterlist sg[];
69 };
70 
71 noinline void tls_err_abort(struct sock *sk, int err)
72 {
73 	WARN_ON_ONCE(err >= 0);
74 	/* sk->sk_err should contain a positive error code. */
75 	WRITE_ONCE(sk->sk_err, -err);
76 	/* Paired with smp_rmb() in tcp_poll() */
77 	smp_wmb();
78 	sk_error_report(sk);
79 }
80 
81 static int __skb_nsg(struct sk_buff *skb, int offset, int len,
82                      unsigned int recursion_level)
83 {
84         int start = skb_headlen(skb);
85         int i, chunk = start - offset;
86         struct sk_buff *frag_iter;
87         int elt = 0;
88 
89         if (unlikely(recursion_level >= 24))
90                 return -EMSGSIZE;
91 
92         if (chunk > 0) {
93                 if (chunk > len)
94                         chunk = len;
95                 elt++;
96                 len -= chunk;
97                 if (len == 0)
98                         return elt;
99                 offset += chunk;
100         }
101 
102         for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
103                 int end;
104 
105                 WARN_ON(start > offset + len);
106 
107                 end = start + skb_frag_size(&skb_shinfo(skb)->frags[i]);
108                 chunk = end - offset;
109                 if (chunk > 0) {
110                         if (chunk > len)
111                                 chunk = len;
112                         elt++;
113                         len -= chunk;
114                         if (len == 0)
115                                 return elt;
116                         offset += chunk;
117                 }
118                 start = end;
119         }
120 
121         if (unlikely(skb_has_frag_list(skb))) {
122                 skb_walk_frags(skb, frag_iter) {
123                         int end, ret;
124 
125                         WARN_ON(start > offset + len);
126 
127                         end = start + frag_iter->len;
128                         chunk = end - offset;
129                         if (chunk > 0) {
130                                 if (chunk > len)
131                                         chunk = len;
132                                 ret = __skb_nsg(frag_iter, offset - start, chunk,
133                                                 recursion_level + 1);
134                                 if (unlikely(ret < 0))
135                                         return ret;
136                                 elt += ret;
137                                 len -= chunk;
138                                 if (len == 0)
139                                         return elt;
140                                 offset += chunk;
141                         }
142                         start = end;
143                 }
144         }
145         BUG_ON(len);
146         return elt;
147 }
148 
149 /* Return the number of scatterlist elements required to completely map the
150  * skb, or -EMSGSIZE if the recursion depth is exceeded.
151  */
152 static int skb_nsg(struct sk_buff *skb, int offset, int len)
153 {
154         return __skb_nsg(skb, offset, len, 0);
155 }
156 
157 static int tls_padding_length(struct tls_prot_info *prot, struct sk_buff *skb,
158 			      struct tls_decrypt_arg *darg)
159 {
160 	struct strp_msg *rxm = strp_msg(skb);
161 	struct tls_msg *tlm = tls_msg(skb);
162 	int sub = 0;
163 
164 	/* Determine zero-padding length */
165 	if (prot->version == TLS_1_3_VERSION) {
166 		int offset = rxm->full_len - TLS_TAG_SIZE - 1;
167 		char content_type = darg->zc ? darg->tail : 0;
168 		int err;
169 
170 		while (content_type == 0) {
171 			if (offset < prot->prepend_size)
172 				return -EBADMSG;
173 			err = skb_copy_bits(skb, rxm->offset + offset,
174 					    &content_type, 1);
175 			if (err)
176 				return err;
177 			if (content_type)
178 				break;
179 			sub++;
180 			offset--;
181 		}
182 		tlm->control = content_type;
183 	}
184 	return sub;
185 }
186 
187 static void tls_decrypt_done(void *data, int err)
188 {
189 	struct aead_request *aead_req = data;
190 	struct crypto_aead *aead = crypto_aead_reqtfm(aead_req);
191 	struct scatterlist *sgout = aead_req->dst;
192 	struct tls_sw_context_rx *ctx;
193 	struct tls_decrypt_ctx *dctx;
194 	struct tls_context *tls_ctx;
195 	struct scatterlist *sg;
196 	unsigned int pages;
197 	struct sock *sk;
198 	int aead_size;
199 
200 	/* If requests get too backlogged crypto API returns -EBUSY and calls
201 	 * ->complete(-EINPROGRESS) immediately followed by ->complete(0)
202 	 * to make waiting for backlog to flush with crypto_wait_req() easier.
203 	 * First wait converts -EBUSY -> -EINPROGRESS, and the second one
204 	 * -EINPROGRESS -> 0.
205 	 * We have a single struct crypto_async_request per direction, this
206 	 * scheme doesn't help us, so just ignore the first ->complete().
207 	 */
208 	if (err == -EINPROGRESS)
209 		return;
210 
211 	aead_size = sizeof(*aead_req) + crypto_aead_reqsize(aead);
212 	aead_size = ALIGN(aead_size, __alignof__(*dctx));
213 	dctx = (void *)((u8 *)aead_req + aead_size);
214 
215 	sk = dctx->sk;
216 	tls_ctx = tls_get_ctx(sk);
217 	ctx = tls_sw_ctx_rx(tls_ctx);
218 
219 	/* Propagate if there was an err */
220 	if (err) {
221 		if (err == -EBADMSG)
222 			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSDECRYPTERROR);
223 		ctx->async_wait.err = err;
224 		tls_err_abort(sk, err);
225 	}
226 
227 	/* Free the destination pages if skb was not decrypted inplace */
228 	if (dctx->free_sgout) {
229 		/* Skip the first S/G entry as it points to AAD */
230 		for_each_sg(sg_next(sgout), sg, UINT_MAX, pages) {
231 			if (!sg)
232 				break;
233 			put_page(sg_page(sg));
234 		}
235 	}
236 
237 	kfree(aead_req);
238 
239 	if (atomic_dec_and_test(&ctx->decrypt_pending))
240 		complete(&ctx->async_wait.completion);
241 }
242 
243 static int tls_decrypt_async_wait(struct tls_sw_context_rx *ctx)
244 {
245 	if (!atomic_dec_and_test(&ctx->decrypt_pending))
246 		crypto_wait_req(-EINPROGRESS, &ctx->async_wait);
247 	atomic_inc(&ctx->decrypt_pending);
248 
249 	return ctx->async_wait.err;
250 }
251 
252 static int tls_do_decryption(struct sock *sk,
253 			     struct scatterlist *sgin,
254 			     struct scatterlist *sgout,
255 			     char *iv_recv,
256 			     size_t data_len,
257 			     struct aead_request *aead_req,
258 			     struct tls_decrypt_arg *darg)
259 {
260 	struct tls_context *tls_ctx = tls_get_ctx(sk);
261 	struct tls_prot_info *prot = &tls_ctx->prot_info;
262 	struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
263 	int ret;
264 
265 	aead_request_set_tfm(aead_req, ctx->aead_recv);
266 	aead_request_set_ad(aead_req, prot->aad_size);
267 	aead_request_set_crypt(aead_req, sgin, sgout,
268 			       data_len + prot->tag_size,
269 			       (u8 *)iv_recv);
270 
271 	if (darg->async) {
272 		aead_request_set_callback(aead_req,
273 					  CRYPTO_TFM_REQ_MAY_BACKLOG,
274 					  tls_decrypt_done, aead_req);
275 		DEBUG_NET_WARN_ON_ONCE(atomic_read(&ctx->decrypt_pending) < 1);
276 		atomic_inc(&ctx->decrypt_pending);
277 	} else {
278 		DECLARE_CRYPTO_WAIT(wait);
279 
280 		aead_request_set_callback(aead_req,
281 					  CRYPTO_TFM_REQ_MAY_BACKLOG,
282 					  crypto_req_done, &wait);
283 		ret = crypto_aead_decrypt(aead_req);
284 		if (ret == -EINPROGRESS || ret == -EBUSY)
285 			ret = crypto_wait_req(ret, &wait);
286 		return ret;
287 	}
288 
289 	ret = crypto_aead_decrypt(aead_req);
290 	if (ret == -EINPROGRESS)
291 		return 0;
292 
293 	if (ret == -EBUSY) {
294 		ret = tls_decrypt_async_wait(ctx);
295 		darg->async_done = true;
296 		/* all completions have run, we're not doing async anymore */
297 		darg->async = false;
298 		return ret;
299 	}
300 
301 	atomic_dec(&ctx->decrypt_pending);
302 	darg->async = false;
303 
304 	return ret;
305 }
306 
307 static void tls_trim_both_msgs(struct sock *sk, int target_size)
308 {
309 	struct tls_context *tls_ctx = tls_get_ctx(sk);
310 	struct tls_prot_info *prot = &tls_ctx->prot_info;
311 	struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
312 	struct tls_rec *rec = ctx->open_rec;
313 
314 	sk_msg_trim(sk, &rec->msg_plaintext, target_size);
315 	if (target_size > 0)
316 		target_size += prot->overhead_size;
317 	sk_msg_trim(sk, &rec->msg_encrypted, target_size);
318 }
319 
320 static int tls_alloc_encrypted_msg(struct sock *sk, int len)
321 {
322 	struct tls_context *tls_ctx = tls_get_ctx(sk);
323 	struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
324 	struct tls_rec *rec = ctx->open_rec;
325 	struct sk_msg *msg_en = &rec->msg_encrypted;
326 
327 	return sk_msg_alloc(sk, msg_en, len, 0);
328 }
329 
330 static int tls_clone_plaintext_msg(struct sock *sk, int required)
331 {
332 	struct tls_context *tls_ctx = tls_get_ctx(sk);
333 	struct tls_prot_info *prot = &tls_ctx->prot_info;
334 	struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
335 	struct tls_rec *rec = ctx->open_rec;
336 	struct sk_msg *msg_pl = &rec->msg_plaintext;
337 	struct sk_msg *msg_en = &rec->msg_encrypted;
338 	int skip, len;
339 
340 	/* We add page references worth len bytes from encrypted sg
341 	 * at the end of plaintext sg. It is guaranteed that msg_en
342 	 * has enough required room (ensured by caller).
343 	 */
344 	len = required - msg_pl->sg.size;
345 
346 	/* Skip initial bytes in msg_en's data to be able to use
347 	 * same offset of both plain and encrypted data.
348 	 */
349 	skip = prot->prepend_size + msg_pl->sg.size;
350 
351 	return sk_msg_clone(sk, msg_pl, msg_en, skip, len);
352 }
353 
354 static struct tls_rec *tls_get_rec(struct sock *sk)
355 {
356 	struct tls_context *tls_ctx = tls_get_ctx(sk);
357 	struct tls_prot_info *prot = &tls_ctx->prot_info;
358 	struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
359 	struct sk_msg *msg_pl, *msg_en;
360 	struct tls_rec *rec;
361 	int mem_size;
362 
363 	mem_size = sizeof(struct tls_rec) + crypto_aead_reqsize(ctx->aead_send);
364 
365 	rec = kzalloc(mem_size, sk->sk_allocation);
366 	if (!rec)
367 		return NULL;
368 
369 	msg_pl = &rec->msg_plaintext;
370 	msg_en = &rec->msg_encrypted;
371 
372 	sk_msg_init(msg_pl);
373 	sk_msg_init(msg_en);
374 
375 	sg_init_table(rec->sg_aead_in, 2);
376 	sg_set_buf(&rec->sg_aead_in[0], rec->aad_space, prot->aad_size);
377 	sg_unmark_end(&rec->sg_aead_in[1]);
378 
379 	sg_init_table(rec->sg_aead_out, 2);
380 	sg_set_buf(&rec->sg_aead_out[0], rec->aad_space, prot->aad_size);
381 	sg_unmark_end(&rec->sg_aead_out[1]);
382 
383 	rec->sk = sk;
384 
385 	return rec;
386 }
387 
388 static void tls_free_rec(struct sock *sk, struct tls_rec *rec)
389 {
390 	sk_msg_free(sk, &rec->msg_encrypted);
391 	sk_msg_free(sk, &rec->msg_plaintext);
392 	kfree(rec);
393 }
394 
395 static void tls_free_open_rec(struct sock *sk)
396 {
397 	struct tls_context *tls_ctx = tls_get_ctx(sk);
398 	struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
399 	struct tls_rec *rec = ctx->open_rec;
400 
401 	if (rec) {
402 		tls_free_rec(sk, rec);
403 		ctx->open_rec = NULL;
404 	}
405 }
406 
407 int tls_tx_records(struct sock *sk, int flags)
408 {
409 	struct tls_context *tls_ctx = tls_get_ctx(sk);
410 	struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
411 	struct tls_rec *rec, *tmp;
412 	struct sk_msg *msg_en;
413 	int tx_flags, rc = 0;
414 
415 	if (tls_is_partially_sent_record(tls_ctx)) {
416 		rec = list_first_entry(&ctx->tx_list,
417 				       struct tls_rec, list);
418 
419 		if (flags == -1)
420 			tx_flags = rec->tx_flags;
421 		else
422 			tx_flags = flags;
423 
424 		rc = tls_push_partial_record(sk, tls_ctx, tx_flags);
425 		if (rc)
426 			goto tx_err;
427 
428 		/* Full record has been transmitted.
429 		 * Remove the head of tx_list
430 		 */
431 		list_del(&rec->list);
432 		sk_msg_free(sk, &rec->msg_plaintext);
433 		kfree(rec);
434 	}
435 
436 	/* Tx all ready records */
437 	list_for_each_entry_safe(rec, tmp, &ctx->tx_list, list) {
438 		if (READ_ONCE(rec->tx_ready)) {
439 			if (flags == -1)
440 				tx_flags = rec->tx_flags;
441 			else
442 				tx_flags = flags;
443 
444 			msg_en = &rec->msg_encrypted;
445 			rc = tls_push_sg(sk, tls_ctx,
446 					 &msg_en->sg.data[msg_en->sg.curr],
447 					 0, tx_flags);
448 			if (rc)
449 				goto tx_err;
450 
451 			list_del(&rec->list);
452 			sk_msg_free(sk, &rec->msg_plaintext);
453 			kfree(rec);
454 		} else {
455 			break;
456 		}
457 	}
458 
459 tx_err:
460 	if (rc < 0 && rc != -EAGAIN)
461 		tls_err_abort(sk, -EBADMSG);
462 
463 	return rc;
464 }
465 
466 static void tls_encrypt_done(void *data, int err)
467 {
468 	struct tls_sw_context_tx *ctx;
469 	struct tls_context *tls_ctx;
470 	struct tls_prot_info *prot;
471 	struct tls_rec *rec = data;
472 	struct scatterlist *sge;
473 	struct sk_msg *msg_en;
474 	struct sock *sk;
475 
476 	if (err == -EINPROGRESS) /* see the comment in tls_decrypt_done() */
477 		return;
478 
479 	msg_en = &rec->msg_encrypted;
480 
481 	sk = rec->sk;
482 	tls_ctx = tls_get_ctx(sk);
483 	prot = &tls_ctx->prot_info;
484 	ctx = tls_sw_ctx_tx(tls_ctx);
485 
486 	sge = sk_msg_elem(msg_en, msg_en->sg.curr);
487 	sge->offset -= prot->prepend_size;
488 	sge->length += prot->prepend_size;
489 
490 	/* Check if error is previously set on socket */
491 	if (err || sk->sk_err) {
492 		rec = NULL;
493 
494 		/* If err is already set on socket, return the same code */
495 		if (sk->sk_err) {
496 			ctx->async_wait.err = -sk->sk_err;
497 		} else {
498 			ctx->async_wait.err = err;
499 			tls_err_abort(sk, err);
500 		}
501 	}
502 
503 	if (rec) {
504 		struct tls_rec *first_rec;
505 
506 		/* Mark the record as ready for transmission */
507 		smp_store_mb(rec->tx_ready, true);
508 
509 		/* If received record is at head of tx_list, schedule tx */
510 		first_rec = list_first_entry(&ctx->tx_list,
511 					     struct tls_rec, list);
512 		if (rec == first_rec) {
513 			/* Schedule the transmission */
514 			if (!test_and_set_bit(BIT_TX_SCHEDULED,
515 					      &ctx->tx_bitmask))
516 				schedule_delayed_work(&ctx->tx_work.work, 1);
517 		}
518 	}
519 
520 	if (atomic_dec_and_test(&ctx->encrypt_pending))
521 		complete(&ctx->async_wait.completion);
522 }
523 
524 static int tls_encrypt_async_wait(struct tls_sw_context_tx *ctx)
525 {
526 	if (!atomic_dec_and_test(&ctx->encrypt_pending))
527 		crypto_wait_req(-EINPROGRESS, &ctx->async_wait);
528 	atomic_inc(&ctx->encrypt_pending);
529 
530 	return ctx->async_wait.err;
531 }
532 
533 static int tls_do_encryption(struct sock *sk,
534 			     struct tls_context *tls_ctx,
535 			     struct tls_sw_context_tx *ctx,
536 			     struct aead_request *aead_req,
537 			     size_t data_len, u32 start)
538 {
539 	struct tls_prot_info *prot = &tls_ctx->prot_info;
540 	struct tls_rec *rec = ctx->open_rec;
541 	struct sk_msg *msg_en = &rec->msg_encrypted;
542 	struct scatterlist *sge = sk_msg_elem(msg_en, start);
543 	int rc, iv_offset = 0;
544 
545 	/* For CCM based ciphers, first byte of IV is a constant */
546 	switch (prot->cipher_type) {
547 	case TLS_CIPHER_AES_CCM_128:
548 		rec->iv_data[0] = TLS_AES_CCM_IV_B0_BYTE;
549 		iv_offset = 1;
550 		break;
551 	case TLS_CIPHER_SM4_CCM:
552 		rec->iv_data[0] = TLS_SM4_CCM_IV_B0_BYTE;
553 		iv_offset = 1;
554 		break;
555 	}
556 
557 	memcpy(&rec->iv_data[iv_offset], tls_ctx->tx.iv,
558 	       prot->iv_size + prot->salt_size);
559 
560 	tls_xor_iv_with_seq(prot, rec->iv_data + iv_offset,
561 			    tls_ctx->tx.rec_seq);
562 
563 	sge->offset += prot->prepend_size;
564 	sge->length -= prot->prepend_size;
565 
566 	msg_en->sg.curr = start;
567 
568 	aead_request_set_tfm(aead_req, ctx->aead_send);
569 	aead_request_set_ad(aead_req, prot->aad_size);
570 	aead_request_set_crypt(aead_req, rec->sg_aead_in,
571 			       rec->sg_aead_out,
572 			       data_len, rec->iv_data);
573 
574 	aead_request_set_callback(aead_req, CRYPTO_TFM_REQ_MAY_BACKLOG,
575 				  tls_encrypt_done, rec);
576 
577 	/* Add the record in tx_list */
578 	list_add_tail((struct list_head *)&rec->list, &ctx->tx_list);
579 	DEBUG_NET_WARN_ON_ONCE(atomic_read(&ctx->encrypt_pending) < 1);
580 	atomic_inc(&ctx->encrypt_pending);
581 
582 	rc = crypto_aead_encrypt(aead_req);
583 	if (rc == -EBUSY) {
584 		rc = tls_encrypt_async_wait(ctx);
585 		rc = rc ?: -EINPROGRESS;
586 	}
587 	if (!rc || rc != -EINPROGRESS) {
588 		atomic_dec(&ctx->encrypt_pending);
589 		sge->offset -= prot->prepend_size;
590 		sge->length += prot->prepend_size;
591 	}
592 
593 	if (!rc) {
594 		WRITE_ONCE(rec->tx_ready, true);
595 	} else if (rc != -EINPROGRESS) {
596 		list_del(&rec->list);
597 		return rc;
598 	}
599 
600 	/* Unhook the record from context if encryption is not failure */
601 	ctx->open_rec = NULL;
602 	tls_advance_record_sn(sk, prot, &tls_ctx->tx);
603 	return rc;
604 }
605 
606 static int tls_split_open_record(struct sock *sk, struct tls_rec *from,
607 				 struct tls_rec **to, struct sk_msg *msg_opl,
608 				 struct sk_msg *msg_oen, u32 split_point,
609 				 u32 tx_overhead_size, u32 *orig_end)
610 {
611 	u32 i, j, bytes = 0, apply = msg_opl->apply_bytes;
612 	struct scatterlist *sge, *osge, *nsge;
613 	u32 orig_size = msg_opl->sg.size;
614 	struct scatterlist tmp = { };
615 	struct sk_msg *msg_npl;
616 	struct tls_rec *new;
617 	int ret;
618 
619 	new = tls_get_rec(sk);
620 	if (!new)
621 		return -ENOMEM;
622 	ret = sk_msg_alloc(sk, &new->msg_encrypted, msg_opl->sg.size +
623 			   tx_overhead_size, 0);
624 	if (ret < 0) {
625 		tls_free_rec(sk, new);
626 		return ret;
627 	}
628 
629 	*orig_end = msg_opl->sg.end;
630 	i = msg_opl->sg.start;
631 	sge = sk_msg_elem(msg_opl, i);
632 	while (apply && sge->length) {
633 		if (sge->length > apply) {
634 			u32 len = sge->length - apply;
635 
636 			get_page(sg_page(sge));
637 			sg_set_page(&tmp, sg_page(sge), len,
638 				    sge->offset + apply);
639 			sge->length = apply;
640 			bytes += apply;
641 			apply = 0;
642 		} else {
643 			apply -= sge->length;
644 			bytes += sge->length;
645 		}
646 
647 		sk_msg_iter_var_next(i);
648 		if (i == msg_opl->sg.end)
649 			break;
650 		sge = sk_msg_elem(msg_opl, i);
651 	}
652 
653 	msg_opl->sg.end = i;
654 	msg_opl->sg.curr = i;
655 	msg_opl->sg.copybreak = 0;
656 	msg_opl->apply_bytes = 0;
657 	msg_opl->sg.size = bytes;
658 
659 	msg_npl = &new->msg_plaintext;
660 	msg_npl->apply_bytes = apply;
661 	msg_npl->sg.size = orig_size - bytes;
662 
663 	j = msg_npl->sg.start;
664 	nsge = sk_msg_elem(msg_npl, j);
665 	if (tmp.length) {
666 		memcpy(nsge, &tmp, sizeof(*nsge));
667 		sk_msg_iter_var_next(j);
668 		nsge = sk_msg_elem(msg_npl, j);
669 	}
670 
671 	osge = sk_msg_elem(msg_opl, i);
672 	while (osge->length) {
673 		memcpy(nsge, osge, sizeof(*nsge));
674 		sg_unmark_end(nsge);
675 		sk_msg_iter_var_next(i);
676 		sk_msg_iter_var_next(j);
677 		if (i == *orig_end)
678 			break;
679 		osge = sk_msg_elem(msg_opl, i);
680 		nsge = sk_msg_elem(msg_npl, j);
681 	}
682 
683 	msg_npl->sg.end = j;
684 	msg_npl->sg.curr = j;
685 	msg_npl->sg.copybreak = 0;
686 
687 	*to = new;
688 	return 0;
689 }
690 
691 static void tls_merge_open_record(struct sock *sk, struct tls_rec *to,
692 				  struct tls_rec *from, u32 orig_end)
693 {
694 	struct sk_msg *msg_npl = &from->msg_plaintext;
695 	struct sk_msg *msg_opl = &to->msg_plaintext;
696 	struct scatterlist *osge, *nsge;
697 	u32 i, j;
698 
699 	i = msg_opl->sg.end;
700 	sk_msg_iter_var_prev(i);
701 	j = msg_npl->sg.start;
702 
703 	osge = sk_msg_elem(msg_opl, i);
704 	nsge = sk_msg_elem(msg_npl, j);
705 
706 	if (sg_page(osge) == sg_page(nsge) &&
707 	    osge->offset + osge->length == nsge->offset) {
708 		osge->length += nsge->length;
709 		put_page(sg_page(nsge));
710 	}
711 
712 	msg_opl->sg.end = orig_end;
713 	msg_opl->sg.curr = orig_end;
714 	msg_opl->sg.copybreak = 0;
715 	msg_opl->apply_bytes = msg_opl->sg.size + msg_npl->sg.size;
716 	msg_opl->sg.size += msg_npl->sg.size;
717 
718 	sk_msg_free(sk, &to->msg_encrypted);
719 	sk_msg_xfer_full(&to->msg_encrypted, &from->msg_encrypted);
720 
721 	kfree(from);
722 }
723 
724 static int tls_push_record(struct sock *sk, int flags,
725 			   unsigned char record_type)
726 {
727 	struct tls_context *tls_ctx = tls_get_ctx(sk);
728 	struct tls_prot_info *prot = &tls_ctx->prot_info;
729 	struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
730 	struct tls_rec *rec = ctx->open_rec, *tmp = NULL;
731 	u32 i, split_point, orig_end;
732 	struct sk_msg *msg_pl, *msg_en;
733 	struct aead_request *req;
734 	bool split;
735 	int rc;
736 
737 	if (!rec)
738 		return 0;
739 
740 	msg_pl = &rec->msg_plaintext;
741 	msg_en = &rec->msg_encrypted;
742 
743 	split_point = msg_pl->apply_bytes;
744 	split = split_point && split_point < msg_pl->sg.size;
745 	if (unlikely((!split &&
746 		      msg_pl->sg.size +
747 		      prot->overhead_size > msg_en->sg.size) ||
748 		     (split &&
749 		      split_point +
750 		      prot->overhead_size > msg_en->sg.size))) {
751 		split = true;
752 		split_point = msg_en->sg.size;
753 	}
754 	if (split) {
755 		rc = tls_split_open_record(sk, rec, &tmp, msg_pl, msg_en,
756 					   split_point, prot->overhead_size,
757 					   &orig_end);
758 		if (rc < 0)
759 			return rc;
760 		/* This can happen if above tls_split_open_record allocates
761 		 * a single large encryption buffer instead of two smaller
762 		 * ones. In this case adjust pointers and continue without
763 		 * split.
764 		 */
765 		if (!msg_pl->sg.size) {
766 			tls_merge_open_record(sk, rec, tmp, orig_end);
767 			msg_pl = &rec->msg_plaintext;
768 			msg_en = &rec->msg_encrypted;
769 			split = false;
770 		}
771 		sk_msg_trim(sk, msg_en, msg_pl->sg.size +
772 			    prot->overhead_size);
773 	}
774 
775 	rec->tx_flags = flags;
776 	req = &rec->aead_req;
777 
778 	i = msg_pl->sg.end;
779 	sk_msg_iter_var_prev(i);
780 
781 	rec->content_type = record_type;
782 	if (prot->version == TLS_1_3_VERSION) {
783 		/* Add content type to end of message.  No padding added */
784 		sg_set_buf(&rec->sg_content_type, &rec->content_type, 1);
785 		sg_mark_end(&rec->sg_content_type);
786 		sg_chain(msg_pl->sg.data, msg_pl->sg.end + 1,
787 			 &rec->sg_content_type);
788 	} else {
789 		sg_mark_end(sk_msg_elem(msg_pl, i));
790 	}
791 
792 	if (msg_pl->sg.end < msg_pl->sg.start) {
793 		sg_chain(&msg_pl->sg.data[msg_pl->sg.start],
794 			 MAX_SKB_FRAGS - msg_pl->sg.start + 1,
795 			 msg_pl->sg.data);
796 	}
797 
798 	i = msg_pl->sg.start;
799 	sg_chain(rec->sg_aead_in, 2, &msg_pl->sg.data[i]);
800 
801 	i = msg_en->sg.end;
802 	sk_msg_iter_var_prev(i);
803 	sg_mark_end(sk_msg_elem(msg_en, i));
804 
805 	i = msg_en->sg.start;
806 	sg_chain(rec->sg_aead_out, 2, &msg_en->sg.data[i]);
807 
808 	tls_make_aad(rec->aad_space, msg_pl->sg.size + prot->tail_size,
809 		     tls_ctx->tx.rec_seq, record_type, prot);
810 
811 	tls_fill_prepend(tls_ctx,
812 			 page_address(sg_page(&msg_en->sg.data[i])) +
813 			 msg_en->sg.data[i].offset,
814 			 msg_pl->sg.size + prot->tail_size,
815 			 record_type);
816 
817 	tls_ctx->pending_open_record_frags = false;
818 
819 	rc = tls_do_encryption(sk, tls_ctx, ctx, req,
820 			       msg_pl->sg.size + prot->tail_size, i);
821 	if (rc < 0) {
822 		if (rc != -EINPROGRESS) {
823 			tls_err_abort(sk, -EBADMSG);
824 			if (split) {
825 				tls_ctx->pending_open_record_frags = true;
826 				tls_merge_open_record(sk, rec, tmp, orig_end);
827 			}
828 		}
829 		ctx->async_capable = 1;
830 		return rc;
831 	} else if (split) {
832 		msg_pl = &tmp->msg_plaintext;
833 		msg_en = &tmp->msg_encrypted;
834 		sk_msg_trim(sk, msg_en, msg_pl->sg.size + prot->overhead_size);
835 		tls_ctx->pending_open_record_frags = true;
836 		ctx->open_rec = tmp;
837 	}
838 
839 	return tls_tx_records(sk, flags);
840 }
841 
842 static int bpf_exec_tx_verdict(struct sk_msg *msg, struct sock *sk,
843 			       bool full_record, u8 record_type,
844 			       ssize_t *copied, int flags)
845 {
846 	struct tls_context *tls_ctx = tls_get_ctx(sk);
847 	struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
848 	struct sk_msg msg_redir = { };
849 	struct sk_psock *psock;
850 	struct sock *sk_redir;
851 	struct tls_rec *rec;
852 	bool enospc, policy, redir_ingress;
853 	int err = 0, send;
854 	u32 delta = 0;
855 
856 	policy = !(flags & MSG_SENDPAGE_NOPOLICY);
857 	psock = sk_psock_get(sk);
858 	if (!psock || !policy) {
859 		err = tls_push_record(sk, flags, record_type);
860 		if (err && err != -EINPROGRESS && sk->sk_err == EBADMSG) {
861 			*copied -= sk_msg_free(sk, msg);
862 			tls_free_open_rec(sk);
863 			err = -sk->sk_err;
864 		}
865 		if (psock)
866 			sk_psock_put(sk, psock);
867 		return err;
868 	}
869 more_data:
870 	enospc = sk_msg_full(msg);
871 	if (psock->eval == __SK_NONE) {
872 		delta = msg->sg.size;
873 		psock->eval = sk_psock_msg_verdict(sk, psock, msg);
874 		delta -= msg->sg.size;
875 	}
876 	if (msg->cork_bytes && msg->cork_bytes > msg->sg.size &&
877 	    !enospc && !full_record) {
878 		err = -ENOSPC;
879 		goto out_err;
880 	}
881 	msg->cork_bytes = 0;
882 	send = msg->sg.size;
883 	if (msg->apply_bytes && msg->apply_bytes < send)
884 		send = msg->apply_bytes;
885 
886 	switch (psock->eval) {
887 	case __SK_PASS:
888 		err = tls_push_record(sk, flags, record_type);
889 		if (err && err != -EINPROGRESS && sk->sk_err == EBADMSG) {
890 			*copied -= sk_msg_free(sk, msg);
891 			tls_free_open_rec(sk);
892 			err = -sk->sk_err;
893 			goto out_err;
894 		}
895 		break;
896 	case __SK_REDIRECT:
897 		redir_ingress = psock->redir_ingress;
898 		sk_redir = psock->sk_redir;
899 		memcpy(&msg_redir, msg, sizeof(*msg));
900 		if (msg->apply_bytes < send)
901 			msg->apply_bytes = 0;
902 		else
903 			msg->apply_bytes -= send;
904 		sk_msg_return_zero(sk, msg, send);
905 		msg->sg.size -= send;
906 		release_sock(sk);
907 		err = tcp_bpf_sendmsg_redir(sk_redir, redir_ingress,
908 					    &msg_redir, send, flags);
909 		lock_sock(sk);
910 		if (err < 0) {
911 			*copied -= sk_msg_free_nocharge(sk, &msg_redir);
912 			msg->sg.size = 0;
913 		}
914 		if (msg->sg.size == 0)
915 			tls_free_open_rec(sk);
916 		break;
917 	case __SK_DROP:
918 	default:
919 		sk_msg_free_partial(sk, msg, send);
920 		if (msg->apply_bytes < send)
921 			msg->apply_bytes = 0;
922 		else
923 			msg->apply_bytes -= send;
924 		if (msg->sg.size == 0)
925 			tls_free_open_rec(sk);
926 		*copied -= (send + delta);
927 		err = -EACCES;
928 	}
929 
930 	if (likely(!err)) {
931 		bool reset_eval = !ctx->open_rec;
932 
933 		rec = ctx->open_rec;
934 		if (rec) {
935 			msg = &rec->msg_plaintext;
936 			if (!msg->apply_bytes)
937 				reset_eval = true;
938 		}
939 		if (reset_eval) {
940 			psock->eval = __SK_NONE;
941 			if (psock->sk_redir) {
942 				sock_put(psock->sk_redir);
943 				psock->sk_redir = NULL;
944 			}
945 		}
946 		if (rec)
947 			goto more_data;
948 	}
949  out_err:
950 	sk_psock_put(sk, psock);
951 	return err;
952 }
953 
954 static int tls_sw_push_pending_record(struct sock *sk, int flags)
955 {
956 	struct tls_context *tls_ctx = tls_get_ctx(sk);
957 	struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
958 	struct tls_rec *rec = ctx->open_rec;
959 	struct sk_msg *msg_pl;
960 	size_t copied;
961 
962 	if (!rec)
963 		return 0;
964 
965 	msg_pl = &rec->msg_plaintext;
966 	copied = msg_pl->sg.size;
967 	if (!copied)
968 		return 0;
969 
970 	return bpf_exec_tx_verdict(msg_pl, sk, true, TLS_RECORD_TYPE_DATA,
971 				   &copied, flags);
972 }
973 
974 static int tls_sw_sendmsg_splice(struct sock *sk, struct msghdr *msg,
975 				 struct sk_msg *msg_pl, size_t try_to_copy,
976 				 ssize_t *copied)
977 {
978 	struct page *page = NULL, **pages = &page;
979 
980 	do {
981 		ssize_t part;
982 		size_t off;
983 
984 		part = iov_iter_extract_pages(&msg->msg_iter, &pages,
985 					      try_to_copy, 1, 0, &off);
986 		if (part <= 0)
987 			return part ?: -EIO;
988 
989 		if (WARN_ON_ONCE(!sendpage_ok(page))) {
990 			iov_iter_revert(&msg->msg_iter, part);
991 			return -EIO;
992 		}
993 
994 		sk_msg_page_add(msg_pl, page, part, off);
995 		msg_pl->sg.copybreak = 0;
996 		msg_pl->sg.curr = msg_pl->sg.end;
997 		sk_mem_charge(sk, part);
998 		*copied += part;
999 		try_to_copy -= part;
1000 	} while (try_to_copy && !sk_msg_full(msg_pl));
1001 
1002 	return 0;
1003 }
1004 
1005 static int tls_sw_sendmsg_locked(struct sock *sk, struct msghdr *msg,
1006 				 size_t size)
1007 {
1008 	long timeo = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT);
1009 	struct tls_context *tls_ctx = tls_get_ctx(sk);
1010 	struct tls_prot_info *prot = &tls_ctx->prot_info;
1011 	struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
1012 	bool async_capable = ctx->async_capable;
1013 	unsigned char record_type = TLS_RECORD_TYPE_DATA;
1014 	bool is_kvec = iov_iter_is_kvec(&msg->msg_iter);
1015 	bool eor = !(msg->msg_flags & MSG_MORE);
1016 	size_t try_to_copy;
1017 	ssize_t copied = 0;
1018 	struct sk_msg *msg_pl, *msg_en;
1019 	struct tls_rec *rec;
1020 	int required_size;
1021 	int num_async = 0;
1022 	bool full_record;
1023 	int record_room;
1024 	int num_zc = 0;
1025 	int orig_size;
1026 	int ret = 0;
1027 
1028 	if (!eor && (msg->msg_flags & MSG_EOR))
1029 		return -EINVAL;
1030 
1031 	if (unlikely(msg->msg_controllen)) {
1032 		ret = tls_process_cmsg(sk, msg, &record_type);
1033 		if (ret) {
1034 			if (ret == -EINPROGRESS)
1035 				num_async++;
1036 			else if (ret != -EAGAIN)
1037 				goto send_end;
1038 		}
1039 	}
1040 
1041 	while (msg_data_left(msg)) {
1042 		if (sk->sk_err) {
1043 			ret = -sk->sk_err;
1044 			goto send_end;
1045 		}
1046 
1047 		if (ctx->open_rec)
1048 			rec = ctx->open_rec;
1049 		else
1050 			rec = ctx->open_rec = tls_get_rec(sk);
1051 		if (!rec) {
1052 			ret = -ENOMEM;
1053 			goto send_end;
1054 		}
1055 
1056 		msg_pl = &rec->msg_plaintext;
1057 		msg_en = &rec->msg_encrypted;
1058 
1059 		orig_size = msg_pl->sg.size;
1060 		full_record = false;
1061 		try_to_copy = msg_data_left(msg);
1062 		record_room = TLS_MAX_PAYLOAD_SIZE - msg_pl->sg.size;
1063 		if (try_to_copy >= record_room) {
1064 			try_to_copy = record_room;
1065 			full_record = true;
1066 		}
1067 
1068 		required_size = msg_pl->sg.size + try_to_copy +
1069 				prot->overhead_size;
1070 
1071 		if (!sk_stream_memory_free(sk))
1072 			goto wait_for_sndbuf;
1073 
1074 alloc_encrypted:
1075 		ret = tls_alloc_encrypted_msg(sk, required_size);
1076 		if (ret) {
1077 			if (ret != -ENOSPC)
1078 				goto wait_for_memory;
1079 
1080 			/* Adjust try_to_copy according to the amount that was
1081 			 * actually allocated. The difference is due
1082 			 * to max sg elements limit
1083 			 */
1084 			try_to_copy -= required_size - msg_en->sg.size;
1085 			full_record = true;
1086 		}
1087 
1088 		if (try_to_copy && (msg->msg_flags & MSG_SPLICE_PAGES)) {
1089 			ret = tls_sw_sendmsg_splice(sk, msg, msg_pl,
1090 						    try_to_copy, &copied);
1091 			if (ret < 0)
1092 				goto send_end;
1093 			tls_ctx->pending_open_record_frags = true;
1094 
1095 			if (sk_msg_full(msg_pl))
1096 				full_record = true;
1097 
1098 			if (full_record || eor)
1099 				goto copied;
1100 			continue;
1101 		}
1102 
1103 		if (!is_kvec && (full_record || eor) && !async_capable) {
1104 			u32 first = msg_pl->sg.end;
1105 
1106 			ret = sk_msg_zerocopy_from_iter(sk, &msg->msg_iter,
1107 							msg_pl, try_to_copy);
1108 			if (ret)
1109 				goto fallback_to_reg_send;
1110 
1111 			num_zc++;
1112 			copied += try_to_copy;
1113 
1114 			sk_msg_sg_copy_set(msg_pl, first);
1115 			ret = bpf_exec_tx_verdict(msg_pl, sk, full_record,
1116 						  record_type, &copied,
1117 						  msg->msg_flags);
1118 			if (ret) {
1119 				if (ret == -EINPROGRESS)
1120 					num_async++;
1121 				else if (ret == -ENOMEM)
1122 					goto wait_for_memory;
1123 				else if (ctx->open_rec && ret == -ENOSPC)
1124 					goto rollback_iter;
1125 				else if (ret != -EAGAIN)
1126 					goto send_end;
1127 			}
1128 			continue;
1129 rollback_iter:
1130 			copied -= try_to_copy;
1131 			sk_msg_sg_copy_clear(msg_pl, first);
1132 			iov_iter_revert(&msg->msg_iter,
1133 					msg_pl->sg.size - orig_size);
1134 fallback_to_reg_send:
1135 			sk_msg_trim(sk, msg_pl, orig_size);
1136 		}
1137 
1138 		required_size = msg_pl->sg.size + try_to_copy;
1139 
1140 		ret = tls_clone_plaintext_msg(sk, required_size);
1141 		if (ret) {
1142 			if (ret != -ENOSPC)
1143 				goto send_end;
1144 
1145 			/* Adjust try_to_copy according to the amount that was
1146 			 * actually allocated. The difference is due
1147 			 * to max sg elements limit
1148 			 */
1149 			try_to_copy -= required_size - msg_pl->sg.size;
1150 			full_record = true;
1151 			sk_msg_trim(sk, msg_en,
1152 				    msg_pl->sg.size + prot->overhead_size);
1153 		}
1154 
1155 		if (try_to_copy) {
1156 			ret = sk_msg_memcopy_from_iter(sk, &msg->msg_iter,
1157 						       msg_pl, try_to_copy);
1158 			if (ret < 0)
1159 				goto trim_sgl;
1160 		}
1161 
1162 		/* Open records defined only if successfully copied, otherwise
1163 		 * we would trim the sg but not reset the open record frags.
1164 		 */
1165 		tls_ctx->pending_open_record_frags = true;
1166 		copied += try_to_copy;
1167 copied:
1168 		if (full_record || eor) {
1169 			ret = bpf_exec_tx_verdict(msg_pl, sk, full_record,
1170 						  record_type, &copied,
1171 						  msg->msg_flags);
1172 			if (ret) {
1173 				if (ret == -EINPROGRESS)
1174 					num_async++;
1175 				else if (ret == -ENOMEM)
1176 					goto wait_for_memory;
1177 				else if (ret != -EAGAIN) {
1178 					if (ret == -ENOSPC)
1179 						ret = 0;
1180 					goto send_end;
1181 				}
1182 			}
1183 		}
1184 
1185 		continue;
1186 
1187 wait_for_sndbuf:
1188 		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1189 wait_for_memory:
1190 		ret = sk_stream_wait_memory(sk, &timeo);
1191 		if (ret) {
1192 trim_sgl:
1193 			if (ctx->open_rec)
1194 				tls_trim_both_msgs(sk, orig_size);
1195 			goto send_end;
1196 		}
1197 
1198 		if (ctx->open_rec && msg_en->sg.size < required_size)
1199 			goto alloc_encrypted;
1200 	}
1201 
1202 	if (!num_async) {
1203 		goto send_end;
1204 	} else if (num_zc) {
1205 		int err;
1206 
1207 		/* Wait for pending encryptions to get completed */
1208 		err = tls_encrypt_async_wait(ctx);
1209 		if (err) {
1210 			ret = err;
1211 			copied = 0;
1212 		}
1213 	}
1214 
1215 	/* Transmit if any encryptions have completed */
1216 	if (test_and_clear_bit(BIT_TX_SCHEDULED, &ctx->tx_bitmask)) {
1217 		cancel_delayed_work(&ctx->tx_work.work);
1218 		tls_tx_records(sk, msg->msg_flags);
1219 	}
1220 
1221 send_end:
1222 	ret = sk_stream_error(sk, msg->msg_flags, ret);
1223 	return copied > 0 ? copied : ret;
1224 }
1225 
1226 int tls_sw_sendmsg(struct sock *sk, struct msghdr *msg, size_t size)
1227 {
1228 	struct tls_context *tls_ctx = tls_get_ctx(sk);
1229 	int ret;
1230 
1231 	if (msg->msg_flags & ~(MSG_MORE | MSG_DONTWAIT | MSG_NOSIGNAL |
1232 			       MSG_CMSG_COMPAT | MSG_SPLICE_PAGES | MSG_EOR |
1233 			       MSG_SENDPAGE_NOPOLICY))
1234 		return -EOPNOTSUPP;
1235 
1236 	ret = mutex_lock_interruptible(&tls_ctx->tx_lock);
1237 	if (ret)
1238 		return ret;
1239 	lock_sock(sk);
1240 	ret = tls_sw_sendmsg_locked(sk, msg, size);
1241 	release_sock(sk);
1242 	mutex_unlock(&tls_ctx->tx_lock);
1243 	return ret;
1244 }
1245 
1246 /*
1247  * Handle unexpected EOF during splice without SPLICE_F_MORE set.
1248  */
1249 void tls_sw_splice_eof(struct socket *sock)
1250 {
1251 	struct sock *sk = sock->sk;
1252 	struct tls_context *tls_ctx = tls_get_ctx(sk);
1253 	struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
1254 	struct tls_rec *rec;
1255 	struct sk_msg *msg_pl;
1256 	ssize_t copied = 0;
1257 	bool retrying = false;
1258 	int ret = 0;
1259 
1260 	if (!ctx->open_rec)
1261 		return;
1262 
1263 	mutex_lock(&tls_ctx->tx_lock);
1264 	lock_sock(sk);
1265 
1266 retry:
1267 	/* same checks as in tls_sw_push_pending_record() */
1268 	rec = ctx->open_rec;
1269 	if (!rec)
1270 		goto unlock;
1271 
1272 	msg_pl = &rec->msg_plaintext;
1273 	if (msg_pl->sg.size == 0)
1274 		goto unlock;
1275 
1276 	/* Check the BPF advisor and perform transmission. */
1277 	ret = bpf_exec_tx_verdict(msg_pl, sk, false, TLS_RECORD_TYPE_DATA,
1278 				  &copied, 0);
1279 	switch (ret) {
1280 	case 0:
1281 	case -EAGAIN:
1282 		if (retrying)
1283 			goto unlock;
1284 		retrying = true;
1285 		goto retry;
1286 	case -EINPROGRESS:
1287 		break;
1288 	default:
1289 		goto unlock;
1290 	}
1291 
1292 	/* Wait for pending encryptions to get completed */
1293 	if (tls_encrypt_async_wait(ctx))
1294 		goto unlock;
1295 
1296 	/* Transmit if any encryptions have completed */
1297 	if (test_and_clear_bit(BIT_TX_SCHEDULED, &ctx->tx_bitmask)) {
1298 		cancel_delayed_work(&ctx->tx_work.work);
1299 		tls_tx_records(sk, 0);
1300 	}
1301 
1302 unlock:
1303 	release_sock(sk);
1304 	mutex_unlock(&tls_ctx->tx_lock);
1305 }
1306 
1307 static int
1308 tls_rx_rec_wait(struct sock *sk, struct sk_psock *psock, bool nonblock,
1309 		bool released)
1310 {
1311 	struct tls_context *tls_ctx = tls_get_ctx(sk);
1312 	struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
1313 	DEFINE_WAIT_FUNC(wait, woken_wake_function);
1314 	int ret = 0;
1315 	long timeo;
1316 
1317 	timeo = sock_rcvtimeo(sk, nonblock);
1318 
1319 	while (!tls_strp_msg_ready(ctx)) {
1320 		if (!sk_psock_queue_empty(psock))
1321 			return 0;
1322 
1323 		if (sk->sk_err)
1324 			return sock_error(sk);
1325 
1326 		if (ret < 0)
1327 			return ret;
1328 
1329 		if (!skb_queue_empty(&sk->sk_receive_queue)) {
1330 			tls_strp_check_rcv(&ctx->strp);
1331 			if (tls_strp_msg_ready(ctx))
1332 				break;
1333 		}
1334 
1335 		if (sk->sk_shutdown & RCV_SHUTDOWN)
1336 			return 0;
1337 
1338 		if (sock_flag(sk, SOCK_DONE))
1339 			return 0;
1340 
1341 		if (!timeo)
1342 			return -EAGAIN;
1343 
1344 		released = true;
1345 		add_wait_queue(sk_sleep(sk), &wait);
1346 		sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk);
1347 		ret = sk_wait_event(sk, &timeo,
1348 				    tls_strp_msg_ready(ctx) ||
1349 				    !sk_psock_queue_empty(psock),
1350 				    &wait);
1351 		sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk);
1352 		remove_wait_queue(sk_sleep(sk), &wait);
1353 
1354 		/* Handle signals */
1355 		if (signal_pending(current))
1356 			return sock_intr_errno(timeo);
1357 	}
1358 
1359 	tls_strp_msg_load(&ctx->strp, released);
1360 
1361 	return 1;
1362 }
1363 
1364 static int tls_setup_from_iter(struct iov_iter *from,
1365 			       int length, int *pages_used,
1366 			       struct scatterlist *to,
1367 			       int to_max_pages)
1368 {
1369 	int rc = 0, i = 0, num_elem = *pages_used, maxpages;
1370 	struct page *pages[MAX_SKB_FRAGS];
1371 	unsigned int size = 0;
1372 	ssize_t copied, use;
1373 	size_t offset;
1374 
1375 	while (length > 0) {
1376 		i = 0;
1377 		maxpages = to_max_pages - num_elem;
1378 		if (maxpages == 0) {
1379 			rc = -EFAULT;
1380 			goto out;
1381 		}
1382 		copied = iov_iter_get_pages2(from, pages,
1383 					    length,
1384 					    maxpages, &offset);
1385 		if (copied <= 0) {
1386 			rc = -EFAULT;
1387 			goto out;
1388 		}
1389 
1390 		length -= copied;
1391 		size += copied;
1392 		while (copied) {
1393 			use = min_t(int, copied, PAGE_SIZE - offset);
1394 
1395 			sg_set_page(&to[num_elem],
1396 				    pages[i], use, offset);
1397 			sg_unmark_end(&to[num_elem]);
1398 			/* We do not uncharge memory from this API */
1399 
1400 			offset = 0;
1401 			copied -= use;
1402 
1403 			i++;
1404 			num_elem++;
1405 		}
1406 	}
1407 	/* Mark the end in the last sg entry if newly added */
1408 	if (num_elem > *pages_used)
1409 		sg_mark_end(&to[num_elem - 1]);
1410 out:
1411 	if (rc)
1412 		iov_iter_revert(from, size);
1413 	*pages_used = num_elem;
1414 
1415 	return rc;
1416 }
1417 
1418 static struct sk_buff *
1419 tls_alloc_clrtxt_skb(struct sock *sk, struct sk_buff *skb,
1420 		     unsigned int full_len)
1421 {
1422 	struct strp_msg *clr_rxm;
1423 	struct sk_buff *clr_skb;
1424 	int err;
1425 
1426 	clr_skb = alloc_skb_with_frags(0, full_len, TLS_PAGE_ORDER,
1427 				       &err, sk->sk_allocation);
1428 	if (!clr_skb)
1429 		return NULL;
1430 
1431 	skb_copy_header(clr_skb, skb);
1432 	clr_skb->len = full_len;
1433 	clr_skb->data_len = full_len;
1434 
1435 	clr_rxm = strp_msg(clr_skb);
1436 	clr_rxm->offset = 0;
1437 
1438 	return clr_skb;
1439 }
1440 
1441 /* Decrypt handlers
1442  *
1443  * tls_decrypt_sw() and tls_decrypt_device() are decrypt handlers.
1444  * They must transform the darg in/out argument are as follows:
1445  *       |          Input            |         Output
1446  * -------------------------------------------------------------------
1447  *    zc | Zero-copy decrypt allowed | Zero-copy performed
1448  * async | Async decrypt allowed     | Async crypto used / in progress
1449  *   skb |            *              | Output skb
1450  *
1451  * If ZC decryption was performed darg.skb will point to the input skb.
1452  */
1453 
1454 /* This function decrypts the input skb into either out_iov or in out_sg
1455  * or in skb buffers itself. The input parameter 'darg->zc' indicates if
1456  * zero-copy mode needs to be tried or not. With zero-copy mode, either
1457  * out_iov or out_sg must be non-NULL. In case both out_iov and out_sg are
1458  * NULL, then the decryption happens inside skb buffers itself, i.e.
1459  * zero-copy gets disabled and 'darg->zc' is updated.
1460  */
1461 static int tls_decrypt_sg(struct sock *sk, struct iov_iter *out_iov,
1462 			  struct scatterlist *out_sg,
1463 			  struct tls_decrypt_arg *darg)
1464 {
1465 	struct tls_context *tls_ctx = tls_get_ctx(sk);
1466 	struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
1467 	struct tls_prot_info *prot = &tls_ctx->prot_info;
1468 	int n_sgin, n_sgout, aead_size, err, pages = 0;
1469 	struct sk_buff *skb = tls_strp_msg(ctx);
1470 	const struct strp_msg *rxm = strp_msg(skb);
1471 	const struct tls_msg *tlm = tls_msg(skb);
1472 	struct aead_request *aead_req;
1473 	struct scatterlist *sgin = NULL;
1474 	struct scatterlist *sgout = NULL;
1475 	const int data_len = rxm->full_len - prot->overhead_size;
1476 	int tail_pages = !!prot->tail_size;
1477 	struct tls_decrypt_ctx *dctx;
1478 	struct sk_buff *clear_skb;
1479 	int iv_offset = 0;
1480 	u8 *mem;
1481 
1482 	n_sgin = skb_nsg(skb, rxm->offset + prot->prepend_size,
1483 			 rxm->full_len - prot->prepend_size);
1484 	if (n_sgin < 1)
1485 		return n_sgin ?: -EBADMSG;
1486 
1487 	if (darg->zc && (out_iov || out_sg)) {
1488 		clear_skb = NULL;
1489 
1490 		if (out_iov)
1491 			n_sgout = 1 + tail_pages +
1492 				iov_iter_npages_cap(out_iov, INT_MAX, data_len);
1493 		else
1494 			n_sgout = sg_nents(out_sg);
1495 	} else {
1496 		darg->zc = false;
1497 
1498 		clear_skb = tls_alloc_clrtxt_skb(sk, skb, rxm->full_len);
1499 		if (!clear_skb)
1500 			return -ENOMEM;
1501 
1502 		n_sgout = 1 + skb_shinfo(clear_skb)->nr_frags;
1503 	}
1504 
1505 	/* Increment to accommodate AAD */
1506 	n_sgin = n_sgin + 1;
1507 
1508 	/* Allocate a single block of memory which contains
1509 	 *   aead_req || tls_decrypt_ctx.
1510 	 * Both structs are variable length.
1511 	 */
1512 	aead_size = sizeof(*aead_req) + crypto_aead_reqsize(ctx->aead_recv);
1513 	aead_size = ALIGN(aead_size, __alignof__(*dctx));
1514 	mem = kmalloc(aead_size + struct_size(dctx, sg, size_add(n_sgin, n_sgout)),
1515 		      sk->sk_allocation);
1516 	if (!mem) {
1517 		err = -ENOMEM;
1518 		goto exit_free_skb;
1519 	}
1520 
1521 	/* Segment the allocated memory */
1522 	aead_req = (struct aead_request *)mem;
1523 	dctx = (struct tls_decrypt_ctx *)(mem + aead_size);
1524 	dctx->sk = sk;
1525 	sgin = &dctx->sg[0];
1526 	sgout = &dctx->sg[n_sgin];
1527 
1528 	/* For CCM based ciphers, first byte of nonce+iv is a constant */
1529 	switch (prot->cipher_type) {
1530 	case TLS_CIPHER_AES_CCM_128:
1531 		dctx->iv[0] = TLS_AES_CCM_IV_B0_BYTE;
1532 		iv_offset = 1;
1533 		break;
1534 	case TLS_CIPHER_SM4_CCM:
1535 		dctx->iv[0] = TLS_SM4_CCM_IV_B0_BYTE;
1536 		iv_offset = 1;
1537 		break;
1538 	}
1539 
1540 	/* Prepare IV */
1541 	if (prot->version == TLS_1_3_VERSION ||
1542 	    prot->cipher_type == TLS_CIPHER_CHACHA20_POLY1305) {
1543 		memcpy(&dctx->iv[iv_offset], tls_ctx->rx.iv,
1544 		       prot->iv_size + prot->salt_size);
1545 	} else {
1546 		err = skb_copy_bits(skb, rxm->offset + TLS_HEADER_SIZE,
1547 				    &dctx->iv[iv_offset] + prot->salt_size,
1548 				    prot->iv_size);
1549 		if (err < 0)
1550 			goto exit_free;
1551 		memcpy(&dctx->iv[iv_offset], tls_ctx->rx.iv, prot->salt_size);
1552 	}
1553 	tls_xor_iv_with_seq(prot, &dctx->iv[iv_offset], tls_ctx->rx.rec_seq);
1554 
1555 	/* Prepare AAD */
1556 	tls_make_aad(dctx->aad, rxm->full_len - prot->overhead_size +
1557 		     prot->tail_size,
1558 		     tls_ctx->rx.rec_seq, tlm->control, prot);
1559 
1560 	/* Prepare sgin */
1561 	sg_init_table(sgin, n_sgin);
1562 	sg_set_buf(&sgin[0], dctx->aad, prot->aad_size);
1563 	err = skb_to_sgvec(skb, &sgin[1],
1564 			   rxm->offset + prot->prepend_size,
1565 			   rxm->full_len - prot->prepend_size);
1566 	if (err < 0)
1567 		goto exit_free;
1568 
1569 	if (clear_skb) {
1570 		sg_init_table(sgout, n_sgout);
1571 		sg_set_buf(&sgout[0], dctx->aad, prot->aad_size);
1572 
1573 		err = skb_to_sgvec(clear_skb, &sgout[1], prot->prepend_size,
1574 				   data_len + prot->tail_size);
1575 		if (err < 0)
1576 			goto exit_free;
1577 	} else if (out_iov) {
1578 		sg_init_table(sgout, n_sgout);
1579 		sg_set_buf(&sgout[0], dctx->aad, prot->aad_size);
1580 
1581 		err = tls_setup_from_iter(out_iov, data_len, &pages, &sgout[1],
1582 					  (n_sgout - 1 - tail_pages));
1583 		if (err < 0)
1584 			goto exit_free_pages;
1585 
1586 		if (prot->tail_size) {
1587 			sg_unmark_end(&sgout[pages]);
1588 			sg_set_buf(&sgout[pages + 1], &dctx->tail,
1589 				   prot->tail_size);
1590 			sg_mark_end(&sgout[pages + 1]);
1591 		}
1592 	} else if (out_sg) {
1593 		memcpy(sgout, out_sg, n_sgout * sizeof(*sgout));
1594 	}
1595 	dctx->free_sgout = !!pages;
1596 
1597 	/* Prepare and submit AEAD request */
1598 	err = tls_do_decryption(sk, sgin, sgout, dctx->iv,
1599 				data_len + prot->tail_size, aead_req, darg);
1600 	if (err) {
1601 		if (darg->async_done)
1602 			goto exit_free_skb;
1603 		goto exit_free_pages;
1604 	}
1605 
1606 	darg->skb = clear_skb ?: tls_strp_msg(ctx);
1607 	clear_skb = NULL;
1608 
1609 	if (unlikely(darg->async)) {
1610 		err = tls_strp_msg_hold(&ctx->strp, &ctx->async_hold);
1611 		if (err)
1612 			__skb_queue_tail(&ctx->async_hold, darg->skb);
1613 		return err;
1614 	}
1615 
1616 	if (unlikely(darg->async_done))
1617 		return 0;
1618 
1619 	if (prot->tail_size)
1620 		darg->tail = dctx->tail;
1621 
1622 exit_free_pages:
1623 	/* Release the pages in case iov was mapped to pages */
1624 	for (; pages > 0; pages--)
1625 		put_page(sg_page(&sgout[pages]));
1626 exit_free:
1627 	kfree(mem);
1628 exit_free_skb:
1629 	consume_skb(clear_skb);
1630 	return err;
1631 }
1632 
1633 static int
1634 tls_decrypt_sw(struct sock *sk, struct tls_context *tls_ctx,
1635 	       struct msghdr *msg, struct tls_decrypt_arg *darg)
1636 {
1637 	struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
1638 	struct tls_prot_info *prot = &tls_ctx->prot_info;
1639 	struct strp_msg *rxm;
1640 	int pad, err;
1641 
1642 	err = tls_decrypt_sg(sk, &msg->msg_iter, NULL, darg);
1643 	if (err < 0) {
1644 		if (err == -EBADMSG)
1645 			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSDECRYPTERROR);
1646 		return err;
1647 	}
1648 	/* keep going even for ->async, the code below is TLS 1.3 */
1649 
1650 	/* If opportunistic TLS 1.3 ZC failed retry without ZC */
1651 	if (unlikely(darg->zc && prot->version == TLS_1_3_VERSION &&
1652 		     darg->tail != TLS_RECORD_TYPE_DATA)) {
1653 		darg->zc = false;
1654 		if (!darg->tail)
1655 			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSRXNOPADVIOL);
1656 		TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSDECRYPTRETRY);
1657 		return tls_decrypt_sw(sk, tls_ctx, msg, darg);
1658 	}
1659 
1660 	pad = tls_padding_length(prot, darg->skb, darg);
1661 	if (pad < 0) {
1662 		if (darg->skb != tls_strp_msg(ctx))
1663 			consume_skb(darg->skb);
1664 		return pad;
1665 	}
1666 
1667 	rxm = strp_msg(darg->skb);
1668 	rxm->full_len -= pad;
1669 
1670 	return 0;
1671 }
1672 
1673 static int
1674 tls_decrypt_device(struct sock *sk, struct msghdr *msg,
1675 		   struct tls_context *tls_ctx, struct tls_decrypt_arg *darg)
1676 {
1677 	struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
1678 	struct tls_prot_info *prot = &tls_ctx->prot_info;
1679 	struct strp_msg *rxm;
1680 	int pad, err;
1681 
1682 	if (tls_ctx->rx_conf != TLS_HW)
1683 		return 0;
1684 
1685 	err = tls_device_decrypted(sk, tls_ctx);
1686 	if (err <= 0)
1687 		return err;
1688 
1689 	pad = tls_padding_length(prot, tls_strp_msg(ctx), darg);
1690 	if (pad < 0)
1691 		return pad;
1692 
1693 	darg->async = false;
1694 	darg->skb = tls_strp_msg(ctx);
1695 	/* ->zc downgrade check, in case TLS 1.3 gets here */
1696 	darg->zc &= !(prot->version == TLS_1_3_VERSION &&
1697 		      tls_msg(darg->skb)->control != TLS_RECORD_TYPE_DATA);
1698 
1699 	rxm = strp_msg(darg->skb);
1700 	rxm->full_len -= pad;
1701 
1702 	if (!darg->zc) {
1703 		/* Non-ZC case needs a real skb */
1704 		darg->skb = tls_strp_msg_detach(ctx);
1705 		if (!darg->skb)
1706 			return -ENOMEM;
1707 	} else {
1708 		unsigned int off, len;
1709 
1710 		/* In ZC case nobody cares about the output skb.
1711 		 * Just copy the data here. Note the skb is not fully trimmed.
1712 		 */
1713 		off = rxm->offset + prot->prepend_size;
1714 		len = rxm->full_len - prot->overhead_size;
1715 
1716 		err = skb_copy_datagram_msg(darg->skb, off, msg, len);
1717 		if (err)
1718 			return err;
1719 	}
1720 	return 1;
1721 }
1722 
1723 static int tls_rx_one_record(struct sock *sk, struct msghdr *msg,
1724 			     struct tls_decrypt_arg *darg)
1725 {
1726 	struct tls_context *tls_ctx = tls_get_ctx(sk);
1727 	struct tls_prot_info *prot = &tls_ctx->prot_info;
1728 	struct strp_msg *rxm;
1729 	int err;
1730 
1731 	err = tls_decrypt_device(sk, msg, tls_ctx, darg);
1732 	if (!err)
1733 		err = tls_decrypt_sw(sk, tls_ctx, msg, darg);
1734 	if (err < 0)
1735 		return err;
1736 
1737 	rxm = strp_msg(darg->skb);
1738 	rxm->offset += prot->prepend_size;
1739 	rxm->full_len -= prot->overhead_size;
1740 	tls_advance_record_sn(sk, prot, &tls_ctx->rx);
1741 
1742 	return 0;
1743 }
1744 
1745 int decrypt_skb(struct sock *sk, struct scatterlist *sgout)
1746 {
1747 	struct tls_decrypt_arg darg = { .zc = true, };
1748 
1749 	return tls_decrypt_sg(sk, NULL, sgout, &darg);
1750 }
1751 
1752 static int tls_record_content_type(struct msghdr *msg, struct tls_msg *tlm,
1753 				   u8 *control)
1754 {
1755 	int err;
1756 
1757 	if (!*control) {
1758 		*control = tlm->control;
1759 		if (!*control)
1760 			return -EBADMSG;
1761 
1762 		err = put_cmsg(msg, SOL_TLS, TLS_GET_RECORD_TYPE,
1763 			       sizeof(*control), control);
1764 		if (*control != TLS_RECORD_TYPE_DATA) {
1765 			if (err || msg->msg_flags & MSG_CTRUNC)
1766 				return -EIO;
1767 		}
1768 	} else if (*control != tlm->control) {
1769 		return 0;
1770 	}
1771 
1772 	return 1;
1773 }
1774 
1775 static void tls_rx_rec_done(struct tls_sw_context_rx *ctx)
1776 {
1777 	tls_strp_msg_done(&ctx->strp);
1778 }
1779 
1780 /* This function traverses the rx_list in tls receive context to copies the
1781  * decrypted records into the buffer provided by caller zero copy is not
1782  * true. Further, the records are removed from the rx_list if it is not a peek
1783  * case and the record has been consumed completely.
1784  */
1785 static int process_rx_list(struct tls_sw_context_rx *ctx,
1786 			   struct msghdr *msg,
1787 			   u8 *control,
1788 			   size_t skip,
1789 			   size_t len,
1790 			   bool is_peek,
1791 			   bool *more)
1792 {
1793 	struct sk_buff *skb = skb_peek(&ctx->rx_list);
1794 	struct tls_msg *tlm;
1795 	ssize_t copied = 0;
1796 	int err;
1797 
1798 	while (skip && skb) {
1799 		struct strp_msg *rxm = strp_msg(skb);
1800 		tlm = tls_msg(skb);
1801 
1802 		err = tls_record_content_type(msg, tlm, control);
1803 		if (err <= 0)
1804 			goto more;
1805 
1806 		if (skip < rxm->full_len)
1807 			break;
1808 
1809 		skip = skip - rxm->full_len;
1810 		skb = skb_peek_next(skb, &ctx->rx_list);
1811 	}
1812 
1813 	while (len && skb) {
1814 		struct sk_buff *next_skb;
1815 		struct strp_msg *rxm = strp_msg(skb);
1816 		int chunk = min_t(unsigned int, rxm->full_len - skip, len);
1817 
1818 		tlm = tls_msg(skb);
1819 
1820 		err = tls_record_content_type(msg, tlm, control);
1821 		if (err <= 0)
1822 			goto more;
1823 
1824 		err = skb_copy_datagram_msg(skb, rxm->offset + skip,
1825 					    msg, chunk);
1826 		if (err < 0)
1827 			goto more;
1828 
1829 		len = len - chunk;
1830 		copied = copied + chunk;
1831 
1832 		/* Consume the data from record if it is non-peek case*/
1833 		if (!is_peek) {
1834 			rxm->offset = rxm->offset + chunk;
1835 			rxm->full_len = rxm->full_len - chunk;
1836 
1837 			/* Return if there is unconsumed data in the record */
1838 			if (rxm->full_len - skip)
1839 				break;
1840 		}
1841 
1842 		/* The remaining skip-bytes must lie in 1st record in rx_list.
1843 		 * So from the 2nd record, 'skip' should be 0.
1844 		 */
1845 		skip = 0;
1846 
1847 		if (msg)
1848 			msg->msg_flags |= MSG_EOR;
1849 
1850 		next_skb = skb_peek_next(skb, &ctx->rx_list);
1851 
1852 		if (!is_peek) {
1853 			__skb_unlink(skb, &ctx->rx_list);
1854 			consume_skb(skb);
1855 		}
1856 
1857 		skb = next_skb;
1858 	}
1859 	err = 0;
1860 
1861 out:
1862 	return copied ? : err;
1863 more:
1864 	if (more)
1865 		*more = true;
1866 	goto out;
1867 }
1868 
1869 static bool
1870 tls_read_flush_backlog(struct sock *sk, struct tls_prot_info *prot,
1871 		       size_t len_left, size_t decrypted, ssize_t done,
1872 		       size_t *flushed_at)
1873 {
1874 	size_t max_rec;
1875 
1876 	if (len_left <= decrypted)
1877 		return false;
1878 
1879 	max_rec = prot->overhead_size - prot->tail_size + TLS_MAX_PAYLOAD_SIZE;
1880 	if (done - *flushed_at < SZ_128K && tcp_inq(sk) > max_rec)
1881 		return false;
1882 
1883 	*flushed_at = done;
1884 	return sk_flush_backlog(sk);
1885 }
1886 
1887 static int tls_rx_reader_acquire(struct sock *sk, struct tls_sw_context_rx *ctx,
1888 				 bool nonblock)
1889 {
1890 	long timeo;
1891 	int ret;
1892 
1893 	timeo = sock_rcvtimeo(sk, nonblock);
1894 
1895 	while (unlikely(ctx->reader_present)) {
1896 		DEFINE_WAIT_FUNC(wait, woken_wake_function);
1897 
1898 		ctx->reader_contended = 1;
1899 
1900 		add_wait_queue(&ctx->wq, &wait);
1901 		ret = sk_wait_event(sk, &timeo,
1902 				    !READ_ONCE(ctx->reader_present), &wait);
1903 		remove_wait_queue(&ctx->wq, &wait);
1904 
1905 		if (timeo <= 0)
1906 			return -EAGAIN;
1907 		if (signal_pending(current))
1908 			return sock_intr_errno(timeo);
1909 		if (ret < 0)
1910 			return ret;
1911 	}
1912 
1913 	WRITE_ONCE(ctx->reader_present, 1);
1914 
1915 	return 0;
1916 }
1917 
1918 static int tls_rx_reader_lock(struct sock *sk, struct tls_sw_context_rx *ctx,
1919 			      bool nonblock)
1920 {
1921 	int err;
1922 
1923 	lock_sock(sk);
1924 	err = tls_rx_reader_acquire(sk, ctx, nonblock);
1925 	if (err)
1926 		release_sock(sk);
1927 	return err;
1928 }
1929 
1930 static void tls_rx_reader_release(struct sock *sk, struct tls_sw_context_rx *ctx)
1931 {
1932 	if (unlikely(ctx->reader_contended)) {
1933 		if (wq_has_sleeper(&ctx->wq))
1934 			wake_up(&ctx->wq);
1935 		else
1936 			ctx->reader_contended = 0;
1937 
1938 		WARN_ON_ONCE(!ctx->reader_present);
1939 	}
1940 
1941 	WRITE_ONCE(ctx->reader_present, 0);
1942 }
1943 
1944 static void tls_rx_reader_unlock(struct sock *sk, struct tls_sw_context_rx *ctx)
1945 {
1946 	tls_rx_reader_release(sk, ctx);
1947 	release_sock(sk);
1948 }
1949 
1950 int tls_sw_recvmsg(struct sock *sk,
1951 		   struct msghdr *msg,
1952 		   size_t len,
1953 		   int flags,
1954 		   int *addr_len)
1955 {
1956 	struct tls_context *tls_ctx = tls_get_ctx(sk);
1957 	struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
1958 	struct tls_prot_info *prot = &tls_ctx->prot_info;
1959 	ssize_t decrypted = 0, async_copy_bytes = 0;
1960 	struct sk_psock *psock;
1961 	unsigned char control = 0;
1962 	size_t flushed_at = 0;
1963 	struct strp_msg *rxm;
1964 	struct tls_msg *tlm;
1965 	ssize_t copied = 0;
1966 	ssize_t peeked = 0;
1967 	bool async = false;
1968 	int target, err;
1969 	bool is_kvec = iov_iter_is_kvec(&msg->msg_iter);
1970 	bool is_peek = flags & MSG_PEEK;
1971 	bool rx_more = false;
1972 	bool released = true;
1973 	bool bpf_strp_enabled;
1974 	bool zc_capable;
1975 
1976 	if (unlikely(flags & MSG_ERRQUEUE))
1977 		return sock_recv_errqueue(sk, msg, len, SOL_IP, IP_RECVERR);
1978 
1979 	err = tls_rx_reader_lock(sk, ctx, flags & MSG_DONTWAIT);
1980 	if (err < 0)
1981 		return err;
1982 	psock = sk_psock_get(sk);
1983 	bpf_strp_enabled = sk_psock_strp_enabled(psock);
1984 
1985 	/* If crypto failed the connection is broken */
1986 	err = ctx->async_wait.err;
1987 	if (err)
1988 		goto end;
1989 
1990 	/* Process pending decrypted records. It must be non-zero-copy */
1991 	err = process_rx_list(ctx, msg, &control, 0, len, is_peek, &rx_more);
1992 	if (err < 0)
1993 		goto end;
1994 
1995 	copied = err;
1996 	if (len <= copied || (copied && control != TLS_RECORD_TYPE_DATA) || rx_more)
1997 		goto end;
1998 
1999 	target = sock_rcvlowat(sk, flags & MSG_WAITALL, len);
2000 	len = len - copied;
2001 
2002 	zc_capable = !bpf_strp_enabled && !is_kvec && !is_peek &&
2003 		ctx->zc_capable;
2004 	decrypted = 0;
2005 	while (len && (decrypted + copied < target || tls_strp_msg_ready(ctx))) {
2006 		struct tls_decrypt_arg darg;
2007 		int to_decrypt, chunk;
2008 
2009 		err = tls_rx_rec_wait(sk, psock, flags & MSG_DONTWAIT,
2010 				      released);
2011 		if (err <= 0) {
2012 			if (psock) {
2013 				chunk = sk_msg_recvmsg(sk, psock, msg, len,
2014 						       flags);
2015 				if (chunk > 0) {
2016 					decrypted += chunk;
2017 					len -= chunk;
2018 					continue;
2019 				}
2020 			}
2021 			goto recv_end;
2022 		}
2023 
2024 		memset(&darg.inargs, 0, sizeof(darg.inargs));
2025 
2026 		rxm = strp_msg(tls_strp_msg(ctx));
2027 		tlm = tls_msg(tls_strp_msg(ctx));
2028 
2029 		to_decrypt = rxm->full_len - prot->overhead_size;
2030 
2031 		if (zc_capable && to_decrypt <= len &&
2032 		    tlm->control == TLS_RECORD_TYPE_DATA)
2033 			darg.zc = true;
2034 
2035 		/* Do not use async mode if record is non-data */
2036 		if (tlm->control == TLS_RECORD_TYPE_DATA && !bpf_strp_enabled)
2037 			darg.async = ctx->async_capable;
2038 		else
2039 			darg.async = false;
2040 
2041 		err = tls_rx_one_record(sk, msg, &darg);
2042 		if (err < 0) {
2043 			tls_err_abort(sk, -EBADMSG);
2044 			goto recv_end;
2045 		}
2046 
2047 		async |= darg.async;
2048 
2049 		/* If the type of records being processed is not known yet,
2050 		 * set it to record type just dequeued. If it is already known,
2051 		 * but does not match the record type just dequeued, go to end.
2052 		 * We always get record type here since for tls1.2, record type
2053 		 * is known just after record is dequeued from stream parser.
2054 		 * For tls1.3, we disable async.
2055 		 */
2056 		err = tls_record_content_type(msg, tls_msg(darg.skb), &control);
2057 		if (err <= 0) {
2058 			DEBUG_NET_WARN_ON_ONCE(darg.zc);
2059 			tls_rx_rec_done(ctx);
2060 put_on_rx_list_err:
2061 			__skb_queue_tail(&ctx->rx_list, darg.skb);
2062 			goto recv_end;
2063 		}
2064 
2065 		/* periodically flush backlog, and feed strparser */
2066 		released = tls_read_flush_backlog(sk, prot, len, to_decrypt,
2067 						  decrypted + copied,
2068 						  &flushed_at);
2069 
2070 		/* TLS 1.3 may have updated the length by more than overhead */
2071 		rxm = strp_msg(darg.skb);
2072 		chunk = rxm->full_len;
2073 		tls_rx_rec_done(ctx);
2074 
2075 		if (!darg.zc) {
2076 			bool partially_consumed = chunk > len;
2077 			struct sk_buff *skb = darg.skb;
2078 
2079 			DEBUG_NET_WARN_ON_ONCE(darg.skb == ctx->strp.anchor);
2080 
2081 			if (async) {
2082 				/* TLS 1.2-only, to_decrypt must be text len */
2083 				chunk = min_t(int, to_decrypt, len);
2084 				async_copy_bytes += chunk;
2085 put_on_rx_list:
2086 				decrypted += chunk;
2087 				len -= chunk;
2088 				__skb_queue_tail(&ctx->rx_list, skb);
2089 				if (unlikely(control != TLS_RECORD_TYPE_DATA))
2090 					break;
2091 				continue;
2092 			}
2093 
2094 			if (bpf_strp_enabled) {
2095 				released = true;
2096 				err = sk_psock_tls_strp_read(psock, skb);
2097 				if (err != __SK_PASS) {
2098 					rxm->offset = rxm->offset + rxm->full_len;
2099 					rxm->full_len = 0;
2100 					if (err == __SK_DROP)
2101 						consume_skb(skb);
2102 					continue;
2103 				}
2104 			}
2105 
2106 			if (partially_consumed)
2107 				chunk = len;
2108 
2109 			err = skb_copy_datagram_msg(skb, rxm->offset,
2110 						    msg, chunk);
2111 			if (err < 0)
2112 				goto put_on_rx_list_err;
2113 
2114 			if (is_peek) {
2115 				peeked += chunk;
2116 				goto put_on_rx_list;
2117 			}
2118 
2119 			if (partially_consumed) {
2120 				rxm->offset += chunk;
2121 				rxm->full_len -= chunk;
2122 				goto put_on_rx_list;
2123 			}
2124 
2125 			consume_skb(skb);
2126 		}
2127 
2128 		decrypted += chunk;
2129 		len -= chunk;
2130 
2131 		/* Return full control message to userspace before trying
2132 		 * to parse another message type
2133 		 */
2134 		msg->msg_flags |= MSG_EOR;
2135 		if (control != TLS_RECORD_TYPE_DATA)
2136 			break;
2137 	}
2138 
2139 recv_end:
2140 	if (async) {
2141 		int ret;
2142 
2143 		/* Wait for all previously submitted records to be decrypted */
2144 		ret = tls_decrypt_async_wait(ctx);
2145 		__skb_queue_purge(&ctx->async_hold);
2146 
2147 		if (ret) {
2148 			if (err >= 0 || err == -EINPROGRESS)
2149 				err = ret;
2150 			decrypted = 0;
2151 			goto end;
2152 		}
2153 
2154 		/* Drain records from the rx_list & copy if required */
2155 		if (is_peek)
2156 			err = process_rx_list(ctx, msg, &control, copied + peeked,
2157 					      decrypted - peeked, is_peek, NULL);
2158 		else
2159 			err = process_rx_list(ctx, msg, &control, 0,
2160 					      async_copy_bytes, is_peek, NULL);
2161 
2162 		/* we could have copied less than we wanted, and possibly nothing */
2163 		decrypted += max(err, 0) - async_copy_bytes;
2164 	}
2165 
2166 	copied += decrypted;
2167 
2168 end:
2169 	tls_rx_reader_unlock(sk, ctx);
2170 	if (psock)
2171 		sk_psock_put(sk, psock);
2172 	return copied ? : err;
2173 }
2174 
2175 ssize_t tls_sw_splice_read(struct socket *sock,  loff_t *ppos,
2176 			   struct pipe_inode_info *pipe,
2177 			   size_t len, unsigned int flags)
2178 {
2179 	struct tls_context *tls_ctx = tls_get_ctx(sock->sk);
2180 	struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
2181 	struct strp_msg *rxm = NULL;
2182 	struct sock *sk = sock->sk;
2183 	struct tls_msg *tlm;
2184 	struct sk_buff *skb;
2185 	ssize_t copied = 0;
2186 	int chunk;
2187 	int err;
2188 
2189 	err = tls_rx_reader_lock(sk, ctx, flags & SPLICE_F_NONBLOCK);
2190 	if (err < 0)
2191 		return err;
2192 
2193 	if (!skb_queue_empty(&ctx->rx_list)) {
2194 		skb = __skb_dequeue(&ctx->rx_list);
2195 	} else {
2196 		struct tls_decrypt_arg darg;
2197 
2198 		err = tls_rx_rec_wait(sk, NULL, flags & SPLICE_F_NONBLOCK,
2199 				      true);
2200 		if (err <= 0)
2201 			goto splice_read_end;
2202 
2203 		memset(&darg.inargs, 0, sizeof(darg.inargs));
2204 
2205 		err = tls_rx_one_record(sk, NULL, &darg);
2206 		if (err < 0) {
2207 			tls_err_abort(sk, -EBADMSG);
2208 			goto splice_read_end;
2209 		}
2210 
2211 		tls_rx_rec_done(ctx);
2212 		skb = darg.skb;
2213 	}
2214 
2215 	rxm = strp_msg(skb);
2216 	tlm = tls_msg(skb);
2217 
2218 	/* splice does not support reading control messages */
2219 	if (tlm->control != TLS_RECORD_TYPE_DATA) {
2220 		err = -EINVAL;
2221 		goto splice_requeue;
2222 	}
2223 
2224 	chunk = min_t(unsigned int, rxm->full_len, len);
2225 	copied = skb_splice_bits(skb, sk, rxm->offset, pipe, chunk, flags);
2226 	if (copied < 0)
2227 		goto splice_requeue;
2228 
2229 	if (chunk < rxm->full_len) {
2230 		rxm->offset += len;
2231 		rxm->full_len -= len;
2232 		goto splice_requeue;
2233 	}
2234 
2235 	consume_skb(skb);
2236 
2237 splice_read_end:
2238 	tls_rx_reader_unlock(sk, ctx);
2239 	return copied ? : err;
2240 
2241 splice_requeue:
2242 	__skb_queue_head(&ctx->rx_list, skb);
2243 	goto splice_read_end;
2244 }
2245 
2246 int tls_sw_read_sock(struct sock *sk, read_descriptor_t *desc,
2247 		     sk_read_actor_t read_actor)
2248 {
2249 	struct tls_context *tls_ctx = tls_get_ctx(sk);
2250 	struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
2251 	struct tls_prot_info *prot = &tls_ctx->prot_info;
2252 	struct strp_msg *rxm = NULL;
2253 	struct sk_buff *skb = NULL;
2254 	struct sk_psock *psock;
2255 	size_t flushed_at = 0;
2256 	bool released = true;
2257 	struct tls_msg *tlm;
2258 	ssize_t copied = 0;
2259 	ssize_t decrypted;
2260 	int err, used;
2261 
2262 	psock = sk_psock_get(sk);
2263 	if (psock) {
2264 		sk_psock_put(sk, psock);
2265 		return -EINVAL;
2266 	}
2267 	err = tls_rx_reader_acquire(sk, ctx, true);
2268 	if (err < 0)
2269 		return err;
2270 
2271 	/* If crypto failed the connection is broken */
2272 	err = ctx->async_wait.err;
2273 	if (err)
2274 		goto read_sock_end;
2275 
2276 	decrypted = 0;
2277 	do {
2278 		if (!skb_queue_empty(&ctx->rx_list)) {
2279 			skb = __skb_dequeue(&ctx->rx_list);
2280 			rxm = strp_msg(skb);
2281 			tlm = tls_msg(skb);
2282 		} else {
2283 			struct tls_decrypt_arg darg;
2284 
2285 			err = tls_rx_rec_wait(sk, NULL, true, released);
2286 			if (err <= 0)
2287 				goto read_sock_end;
2288 
2289 			memset(&darg.inargs, 0, sizeof(darg.inargs));
2290 
2291 			err = tls_rx_one_record(sk, NULL, &darg);
2292 			if (err < 0) {
2293 				tls_err_abort(sk, -EBADMSG);
2294 				goto read_sock_end;
2295 			}
2296 
2297 			released = tls_read_flush_backlog(sk, prot, INT_MAX,
2298 							  0, decrypted,
2299 							  &flushed_at);
2300 			skb = darg.skb;
2301 			rxm = strp_msg(skb);
2302 			tlm = tls_msg(skb);
2303 			decrypted += rxm->full_len;
2304 
2305 			tls_rx_rec_done(ctx);
2306 		}
2307 
2308 		/* read_sock does not support reading control messages */
2309 		if (tlm->control != TLS_RECORD_TYPE_DATA) {
2310 			err = -EINVAL;
2311 			goto read_sock_requeue;
2312 		}
2313 
2314 		used = read_actor(desc, skb, rxm->offset, rxm->full_len);
2315 		if (used <= 0) {
2316 			if (!copied)
2317 				err = used;
2318 			goto read_sock_requeue;
2319 		}
2320 		copied += used;
2321 		if (used < rxm->full_len) {
2322 			rxm->offset += used;
2323 			rxm->full_len -= used;
2324 			if (!desc->count)
2325 				goto read_sock_requeue;
2326 		} else {
2327 			consume_skb(skb);
2328 			if (!desc->count)
2329 				skb = NULL;
2330 		}
2331 	} while (skb);
2332 
2333 read_sock_end:
2334 	tls_rx_reader_release(sk, ctx);
2335 	return copied ? : err;
2336 
2337 read_sock_requeue:
2338 	__skb_queue_head(&ctx->rx_list, skb);
2339 	goto read_sock_end;
2340 }
2341 
2342 bool tls_sw_sock_is_readable(struct sock *sk)
2343 {
2344 	struct tls_context *tls_ctx = tls_get_ctx(sk);
2345 	struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
2346 	bool ingress_empty = true;
2347 	struct sk_psock *psock;
2348 
2349 	rcu_read_lock();
2350 	psock = sk_psock(sk);
2351 	if (psock)
2352 		ingress_empty = list_empty(&psock->ingress_msg);
2353 	rcu_read_unlock();
2354 
2355 	return !ingress_empty || tls_strp_msg_ready(ctx) ||
2356 		!skb_queue_empty(&ctx->rx_list);
2357 }
2358 
2359 int tls_rx_msg_size(struct tls_strparser *strp, struct sk_buff *skb)
2360 {
2361 	struct tls_context *tls_ctx = tls_get_ctx(strp->sk);
2362 	struct tls_prot_info *prot = &tls_ctx->prot_info;
2363 	char header[TLS_HEADER_SIZE + TLS_MAX_IV_SIZE];
2364 	size_t cipher_overhead;
2365 	size_t data_len = 0;
2366 	int ret;
2367 
2368 	/* Verify that we have a full TLS header, or wait for more data */
2369 	if (strp->stm.offset + prot->prepend_size > skb->len)
2370 		return 0;
2371 
2372 	/* Sanity-check size of on-stack buffer. */
2373 	if (WARN_ON(prot->prepend_size > sizeof(header))) {
2374 		ret = -EINVAL;
2375 		goto read_failure;
2376 	}
2377 
2378 	/* Linearize header to local buffer */
2379 	ret = skb_copy_bits(skb, strp->stm.offset, header, prot->prepend_size);
2380 	if (ret < 0)
2381 		goto read_failure;
2382 
2383 	strp->mark = header[0];
2384 
2385 	data_len = ((header[4] & 0xFF) | (header[3] << 8));
2386 
2387 	cipher_overhead = prot->tag_size;
2388 	if (prot->version != TLS_1_3_VERSION &&
2389 	    prot->cipher_type != TLS_CIPHER_CHACHA20_POLY1305)
2390 		cipher_overhead += prot->iv_size;
2391 
2392 	if (data_len > TLS_MAX_PAYLOAD_SIZE + cipher_overhead +
2393 	    prot->tail_size) {
2394 		ret = -EMSGSIZE;
2395 		goto read_failure;
2396 	}
2397 	if (data_len < cipher_overhead) {
2398 		ret = -EBADMSG;
2399 		goto read_failure;
2400 	}
2401 
2402 	/* Note that both TLS1.3 and TLS1.2 use TLS_1_2 version here */
2403 	if (header[1] != TLS_1_2_VERSION_MINOR ||
2404 	    header[2] != TLS_1_2_VERSION_MAJOR) {
2405 		ret = -EINVAL;
2406 		goto read_failure;
2407 	}
2408 
2409 	tls_device_rx_resync_new_rec(strp->sk, data_len + TLS_HEADER_SIZE,
2410 				     TCP_SKB_CB(skb)->seq + strp->stm.offset);
2411 	return data_len + TLS_HEADER_SIZE;
2412 
2413 read_failure:
2414 	tls_err_abort(strp->sk, ret);
2415 
2416 	return ret;
2417 }
2418 
2419 void tls_rx_msg_ready(struct tls_strparser *strp)
2420 {
2421 	struct tls_sw_context_rx *ctx;
2422 
2423 	ctx = container_of(strp, struct tls_sw_context_rx, strp);
2424 	ctx->saved_data_ready(strp->sk);
2425 }
2426 
2427 static void tls_data_ready(struct sock *sk)
2428 {
2429 	struct tls_context *tls_ctx = tls_get_ctx(sk);
2430 	struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
2431 	struct sk_psock *psock;
2432 	gfp_t alloc_save;
2433 
2434 	trace_sk_data_ready(sk);
2435 
2436 	alloc_save = sk->sk_allocation;
2437 	sk->sk_allocation = GFP_ATOMIC;
2438 	tls_strp_data_ready(&ctx->strp);
2439 	sk->sk_allocation = alloc_save;
2440 
2441 	psock = sk_psock_get(sk);
2442 	if (psock) {
2443 		if (!list_empty(&psock->ingress_msg))
2444 			ctx->saved_data_ready(sk);
2445 		sk_psock_put(sk, psock);
2446 	}
2447 }
2448 
2449 void tls_sw_cancel_work_tx(struct tls_context *tls_ctx)
2450 {
2451 	struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
2452 
2453 	set_bit(BIT_TX_CLOSING, &ctx->tx_bitmask);
2454 	set_bit(BIT_TX_SCHEDULED, &ctx->tx_bitmask);
2455 	cancel_delayed_work_sync(&ctx->tx_work.work);
2456 }
2457 
2458 void tls_sw_release_resources_tx(struct sock *sk)
2459 {
2460 	struct tls_context *tls_ctx = tls_get_ctx(sk);
2461 	struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
2462 	struct tls_rec *rec, *tmp;
2463 
2464 	/* Wait for any pending async encryptions to complete */
2465 	tls_encrypt_async_wait(ctx);
2466 
2467 	tls_tx_records(sk, -1);
2468 
2469 	/* Free up un-sent records in tx_list. First, free
2470 	 * the partially sent record if any at head of tx_list.
2471 	 */
2472 	if (tls_ctx->partially_sent_record) {
2473 		tls_free_partial_record(sk, tls_ctx);
2474 		rec = list_first_entry(&ctx->tx_list,
2475 				       struct tls_rec, list);
2476 		list_del(&rec->list);
2477 		sk_msg_free(sk, &rec->msg_plaintext);
2478 		kfree(rec);
2479 	}
2480 
2481 	list_for_each_entry_safe(rec, tmp, &ctx->tx_list, list) {
2482 		list_del(&rec->list);
2483 		sk_msg_free(sk, &rec->msg_encrypted);
2484 		sk_msg_free(sk, &rec->msg_plaintext);
2485 		kfree(rec);
2486 	}
2487 
2488 	crypto_free_aead(ctx->aead_send);
2489 	tls_free_open_rec(sk);
2490 }
2491 
2492 void tls_sw_free_ctx_tx(struct tls_context *tls_ctx)
2493 {
2494 	struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
2495 
2496 	kfree(ctx);
2497 }
2498 
2499 void tls_sw_release_resources_rx(struct sock *sk)
2500 {
2501 	struct tls_context *tls_ctx = tls_get_ctx(sk);
2502 	struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
2503 
2504 	if (ctx->aead_recv) {
2505 		__skb_queue_purge(&ctx->rx_list);
2506 		crypto_free_aead(ctx->aead_recv);
2507 		tls_strp_stop(&ctx->strp);
2508 		/* If tls_sw_strparser_arm() was not called (cleanup paths)
2509 		 * we still want to tls_strp_stop(), but sk->sk_data_ready was
2510 		 * never swapped.
2511 		 */
2512 		if (ctx->saved_data_ready) {
2513 			write_lock_bh(&sk->sk_callback_lock);
2514 			sk->sk_data_ready = ctx->saved_data_ready;
2515 			write_unlock_bh(&sk->sk_callback_lock);
2516 		}
2517 	}
2518 }
2519 
2520 void tls_sw_strparser_done(struct tls_context *tls_ctx)
2521 {
2522 	struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
2523 
2524 	tls_strp_done(&ctx->strp);
2525 }
2526 
2527 void tls_sw_free_ctx_rx(struct tls_context *tls_ctx)
2528 {
2529 	struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
2530 
2531 	kfree(ctx);
2532 }
2533 
2534 void tls_sw_free_resources_rx(struct sock *sk)
2535 {
2536 	struct tls_context *tls_ctx = tls_get_ctx(sk);
2537 
2538 	tls_sw_release_resources_rx(sk);
2539 	tls_sw_free_ctx_rx(tls_ctx);
2540 }
2541 
2542 /* The work handler to transmitt the encrypted records in tx_list */
2543 static void tx_work_handler(struct work_struct *work)
2544 {
2545 	struct delayed_work *delayed_work = to_delayed_work(work);
2546 	struct tx_work *tx_work = container_of(delayed_work,
2547 					       struct tx_work, work);
2548 	struct sock *sk = tx_work->sk;
2549 	struct tls_context *tls_ctx = tls_get_ctx(sk);
2550 	struct tls_sw_context_tx *ctx;
2551 
2552 	if (unlikely(!tls_ctx))
2553 		return;
2554 
2555 	ctx = tls_sw_ctx_tx(tls_ctx);
2556 	if (test_bit(BIT_TX_CLOSING, &ctx->tx_bitmask))
2557 		return;
2558 
2559 	if (!test_and_clear_bit(BIT_TX_SCHEDULED, &ctx->tx_bitmask))
2560 		return;
2561 
2562 	if (mutex_trylock(&tls_ctx->tx_lock)) {
2563 		lock_sock(sk);
2564 		tls_tx_records(sk, -1);
2565 		release_sock(sk);
2566 		mutex_unlock(&tls_ctx->tx_lock);
2567 	} else if (!test_and_set_bit(BIT_TX_SCHEDULED, &ctx->tx_bitmask)) {
2568 		/* Someone is holding the tx_lock, they will likely run Tx
2569 		 * and cancel the work on their way out of the lock section.
2570 		 * Schedule a long delay just in case.
2571 		 */
2572 		schedule_delayed_work(&ctx->tx_work.work, msecs_to_jiffies(10));
2573 	}
2574 }
2575 
2576 static bool tls_is_tx_ready(struct tls_sw_context_tx *ctx)
2577 {
2578 	struct tls_rec *rec;
2579 
2580 	rec = list_first_entry_or_null(&ctx->tx_list, struct tls_rec, list);
2581 	if (!rec)
2582 		return false;
2583 
2584 	return READ_ONCE(rec->tx_ready);
2585 }
2586 
2587 void tls_sw_write_space(struct sock *sk, struct tls_context *ctx)
2588 {
2589 	struct tls_sw_context_tx *tx_ctx = tls_sw_ctx_tx(ctx);
2590 
2591 	/* Schedule the transmission if tx list is ready */
2592 	if (tls_is_tx_ready(tx_ctx) &&
2593 	    !test_and_set_bit(BIT_TX_SCHEDULED, &tx_ctx->tx_bitmask))
2594 		schedule_delayed_work(&tx_ctx->tx_work.work, 0);
2595 }
2596 
2597 void tls_sw_strparser_arm(struct sock *sk, struct tls_context *tls_ctx)
2598 {
2599 	struct tls_sw_context_rx *rx_ctx = tls_sw_ctx_rx(tls_ctx);
2600 
2601 	write_lock_bh(&sk->sk_callback_lock);
2602 	rx_ctx->saved_data_ready = sk->sk_data_ready;
2603 	sk->sk_data_ready = tls_data_ready;
2604 	write_unlock_bh(&sk->sk_callback_lock);
2605 }
2606 
2607 void tls_update_rx_zc_capable(struct tls_context *tls_ctx)
2608 {
2609 	struct tls_sw_context_rx *rx_ctx = tls_sw_ctx_rx(tls_ctx);
2610 
2611 	rx_ctx->zc_capable = tls_ctx->rx_no_pad ||
2612 		tls_ctx->prot_info.version != TLS_1_3_VERSION;
2613 }
2614 
2615 static struct tls_sw_context_tx *init_ctx_tx(struct tls_context *ctx, struct sock *sk)
2616 {
2617 	struct tls_sw_context_tx *sw_ctx_tx;
2618 
2619 	if (!ctx->priv_ctx_tx) {
2620 		sw_ctx_tx = kzalloc(sizeof(*sw_ctx_tx), GFP_KERNEL);
2621 		if (!sw_ctx_tx)
2622 			return NULL;
2623 	} else {
2624 		sw_ctx_tx = ctx->priv_ctx_tx;
2625 	}
2626 
2627 	crypto_init_wait(&sw_ctx_tx->async_wait);
2628 	atomic_set(&sw_ctx_tx->encrypt_pending, 1);
2629 	INIT_LIST_HEAD(&sw_ctx_tx->tx_list);
2630 	INIT_DELAYED_WORK(&sw_ctx_tx->tx_work.work, tx_work_handler);
2631 	sw_ctx_tx->tx_work.sk = sk;
2632 
2633 	return sw_ctx_tx;
2634 }
2635 
2636 static struct tls_sw_context_rx *init_ctx_rx(struct tls_context *ctx)
2637 {
2638 	struct tls_sw_context_rx *sw_ctx_rx;
2639 
2640 	if (!ctx->priv_ctx_rx) {
2641 		sw_ctx_rx = kzalloc(sizeof(*sw_ctx_rx), GFP_KERNEL);
2642 		if (!sw_ctx_rx)
2643 			return NULL;
2644 	} else {
2645 		sw_ctx_rx = ctx->priv_ctx_rx;
2646 	}
2647 
2648 	crypto_init_wait(&sw_ctx_rx->async_wait);
2649 	atomic_set(&sw_ctx_rx->decrypt_pending, 1);
2650 	init_waitqueue_head(&sw_ctx_rx->wq);
2651 	skb_queue_head_init(&sw_ctx_rx->rx_list);
2652 	skb_queue_head_init(&sw_ctx_rx->async_hold);
2653 
2654 	return sw_ctx_rx;
2655 }
2656 
2657 int init_prot_info(struct tls_prot_info *prot,
2658 		   const struct tls_crypto_info *crypto_info,
2659 		   const struct tls_cipher_desc *cipher_desc)
2660 {
2661 	u16 nonce_size = cipher_desc->nonce;
2662 
2663 	if (crypto_info->version == TLS_1_3_VERSION) {
2664 		nonce_size = 0;
2665 		prot->aad_size = TLS_HEADER_SIZE;
2666 		prot->tail_size = 1;
2667 	} else {
2668 		prot->aad_size = TLS_AAD_SPACE_SIZE;
2669 		prot->tail_size = 0;
2670 	}
2671 
2672 	/* Sanity-check the sizes for stack allocations. */
2673 	if (nonce_size > TLS_MAX_IV_SIZE || prot->aad_size > TLS_MAX_AAD_SIZE)
2674 		return -EINVAL;
2675 
2676 	prot->version = crypto_info->version;
2677 	prot->cipher_type = crypto_info->cipher_type;
2678 	prot->prepend_size = TLS_HEADER_SIZE + nonce_size;
2679 	prot->tag_size = cipher_desc->tag;
2680 	prot->overhead_size = prot->prepend_size + prot->tag_size + prot->tail_size;
2681 	prot->iv_size = cipher_desc->iv;
2682 	prot->salt_size = cipher_desc->salt;
2683 	prot->rec_seq_size = cipher_desc->rec_seq;
2684 
2685 	return 0;
2686 }
2687 
2688 int tls_set_sw_offload(struct sock *sk, int tx)
2689 {
2690 	struct tls_sw_context_tx *sw_ctx_tx = NULL;
2691 	struct tls_sw_context_rx *sw_ctx_rx = NULL;
2692 	const struct tls_cipher_desc *cipher_desc;
2693 	struct tls_crypto_info *crypto_info;
2694 	char *iv, *rec_seq, *key, *salt;
2695 	struct cipher_context *cctx;
2696 	struct tls_prot_info *prot;
2697 	struct crypto_aead **aead;
2698 	struct tls_context *ctx;
2699 	struct crypto_tfm *tfm;
2700 	int rc = 0;
2701 
2702 	ctx = tls_get_ctx(sk);
2703 	prot = &ctx->prot_info;
2704 
2705 	if (tx) {
2706 		ctx->priv_ctx_tx = init_ctx_tx(ctx, sk);
2707 		if (!ctx->priv_ctx_tx)
2708 			return -ENOMEM;
2709 
2710 		sw_ctx_tx = ctx->priv_ctx_tx;
2711 		crypto_info = &ctx->crypto_send.info;
2712 		cctx = &ctx->tx;
2713 		aead = &sw_ctx_tx->aead_send;
2714 	} else {
2715 		ctx->priv_ctx_rx = init_ctx_rx(ctx);
2716 		if (!ctx->priv_ctx_rx)
2717 			return -ENOMEM;
2718 
2719 		sw_ctx_rx = ctx->priv_ctx_rx;
2720 		crypto_info = &ctx->crypto_recv.info;
2721 		cctx = &ctx->rx;
2722 		aead = &sw_ctx_rx->aead_recv;
2723 	}
2724 
2725 	cipher_desc = get_cipher_desc(crypto_info->cipher_type);
2726 	if (!cipher_desc) {
2727 		rc = -EINVAL;
2728 		goto free_priv;
2729 	}
2730 
2731 	rc = init_prot_info(prot, crypto_info, cipher_desc);
2732 	if (rc)
2733 		goto free_priv;
2734 
2735 	iv = crypto_info_iv(crypto_info, cipher_desc);
2736 	key = crypto_info_key(crypto_info, cipher_desc);
2737 	salt = crypto_info_salt(crypto_info, cipher_desc);
2738 	rec_seq = crypto_info_rec_seq(crypto_info, cipher_desc);
2739 
2740 	memcpy(cctx->iv, salt, cipher_desc->salt);
2741 	memcpy(cctx->iv + cipher_desc->salt, iv, cipher_desc->iv);
2742 	memcpy(cctx->rec_seq, rec_seq, cipher_desc->rec_seq);
2743 
2744 	if (!*aead) {
2745 		*aead = crypto_alloc_aead(cipher_desc->cipher_name, 0, 0);
2746 		if (IS_ERR(*aead)) {
2747 			rc = PTR_ERR(*aead);
2748 			*aead = NULL;
2749 			goto free_priv;
2750 		}
2751 	}
2752 
2753 	ctx->push_pending_record = tls_sw_push_pending_record;
2754 
2755 	rc = crypto_aead_setkey(*aead, key, cipher_desc->key);
2756 	if (rc)
2757 		goto free_aead;
2758 
2759 	rc = crypto_aead_setauthsize(*aead, prot->tag_size);
2760 	if (rc)
2761 		goto free_aead;
2762 
2763 	if (sw_ctx_rx) {
2764 		tfm = crypto_aead_tfm(sw_ctx_rx->aead_recv);
2765 
2766 		tls_update_rx_zc_capable(ctx);
2767 		sw_ctx_rx->async_capable =
2768 			crypto_info->version != TLS_1_3_VERSION &&
2769 			!!(tfm->__crt_alg->cra_flags & CRYPTO_ALG_ASYNC);
2770 
2771 		rc = tls_strp_init(&sw_ctx_rx->strp, sk);
2772 		if (rc)
2773 			goto free_aead;
2774 	}
2775 
2776 	goto out;
2777 
2778 free_aead:
2779 	crypto_free_aead(*aead);
2780 	*aead = NULL;
2781 free_priv:
2782 	if (tx) {
2783 		kfree(ctx->priv_ctx_tx);
2784 		ctx->priv_ctx_tx = NULL;
2785 	} else {
2786 		kfree(ctx->priv_ctx_rx);
2787 		ctx->priv_ctx_rx = NULL;
2788 	}
2789 out:
2790 	return rc;
2791 }
2792