xref: /linux/net/tls/tls_sw.c (revision 9a6b55ac)
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/sched/signal.h>
39 #include <linux/module.h>
40 #include <crypto/aead.h>
41 
42 #include <net/strparser.h>
43 #include <net/tls.h>
44 
45 static int __skb_nsg(struct sk_buff *skb, int offset, int len,
46                      unsigned int recursion_level)
47 {
48         int start = skb_headlen(skb);
49         int i, chunk = start - offset;
50         struct sk_buff *frag_iter;
51         int elt = 0;
52 
53         if (unlikely(recursion_level >= 24))
54                 return -EMSGSIZE;
55 
56         if (chunk > 0) {
57                 if (chunk > len)
58                         chunk = len;
59                 elt++;
60                 len -= chunk;
61                 if (len == 0)
62                         return elt;
63                 offset += chunk;
64         }
65 
66         for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
67                 int end;
68 
69                 WARN_ON(start > offset + len);
70 
71                 end = start + skb_frag_size(&skb_shinfo(skb)->frags[i]);
72                 chunk = end - offset;
73                 if (chunk > 0) {
74                         if (chunk > len)
75                                 chunk = len;
76                         elt++;
77                         len -= chunk;
78                         if (len == 0)
79                                 return elt;
80                         offset += chunk;
81                 }
82                 start = end;
83         }
84 
85         if (unlikely(skb_has_frag_list(skb))) {
86                 skb_walk_frags(skb, frag_iter) {
87                         int end, ret;
88 
89                         WARN_ON(start > offset + len);
90 
91                         end = start + frag_iter->len;
92                         chunk = end - offset;
93                         if (chunk > 0) {
94                                 if (chunk > len)
95                                         chunk = len;
96                                 ret = __skb_nsg(frag_iter, offset - start, chunk,
97                                                 recursion_level + 1);
98                                 if (unlikely(ret < 0))
99                                         return ret;
100                                 elt += ret;
101                                 len -= chunk;
102                                 if (len == 0)
103                                         return elt;
104                                 offset += chunk;
105                         }
106                         start = end;
107                 }
108         }
109         BUG_ON(len);
110         return elt;
111 }
112 
113 /* Return the number of scatterlist elements required to completely map the
114  * skb, or -EMSGSIZE if the recursion depth is exceeded.
115  */
116 static int skb_nsg(struct sk_buff *skb, int offset, int len)
117 {
118         return __skb_nsg(skb, offset, len, 0);
119 }
120 
121 static int padding_length(struct tls_sw_context_rx *ctx,
122 			  struct tls_prot_info *prot, struct sk_buff *skb)
123 {
124 	struct strp_msg *rxm = strp_msg(skb);
125 	int sub = 0;
126 
127 	/* Determine zero-padding length */
128 	if (prot->version == TLS_1_3_VERSION) {
129 		char content_type = 0;
130 		int err;
131 		int back = 17;
132 
133 		while (content_type == 0) {
134 			if (back > rxm->full_len - prot->prepend_size)
135 				return -EBADMSG;
136 			err = skb_copy_bits(skb,
137 					    rxm->offset + rxm->full_len - back,
138 					    &content_type, 1);
139 			if (err)
140 				return err;
141 			if (content_type)
142 				break;
143 			sub++;
144 			back++;
145 		}
146 		ctx->control = content_type;
147 	}
148 	return sub;
149 }
150 
151 static void tls_decrypt_done(struct crypto_async_request *req, int err)
152 {
153 	struct aead_request *aead_req = (struct aead_request *)req;
154 	struct scatterlist *sgout = aead_req->dst;
155 	struct scatterlist *sgin = aead_req->src;
156 	struct tls_sw_context_rx *ctx;
157 	struct tls_context *tls_ctx;
158 	struct tls_prot_info *prot;
159 	struct scatterlist *sg;
160 	struct sk_buff *skb;
161 	unsigned int pages;
162 	int pending;
163 
164 	skb = (struct sk_buff *)req->data;
165 	tls_ctx = tls_get_ctx(skb->sk);
166 	ctx = tls_sw_ctx_rx(tls_ctx);
167 	prot = &tls_ctx->prot_info;
168 
169 	/* Propagate if there was an err */
170 	if (err) {
171 		if (err == -EBADMSG)
172 			TLS_INC_STATS(sock_net(skb->sk),
173 				      LINUX_MIB_TLSDECRYPTERROR);
174 		ctx->async_wait.err = err;
175 		tls_err_abort(skb->sk, err);
176 	} else {
177 		struct strp_msg *rxm = strp_msg(skb);
178 		int pad;
179 
180 		pad = padding_length(ctx, prot, skb);
181 		if (pad < 0) {
182 			ctx->async_wait.err = pad;
183 			tls_err_abort(skb->sk, pad);
184 		} else {
185 			rxm->full_len -= pad;
186 			rxm->offset += prot->prepend_size;
187 			rxm->full_len -= prot->overhead_size;
188 		}
189 	}
190 
191 	/* After using skb->sk to propagate sk through crypto async callback
192 	 * we need to NULL it again.
193 	 */
194 	skb->sk = NULL;
195 
196 
197 	/* Free the destination pages if skb was not decrypted inplace */
198 	if (sgout != sgin) {
199 		/* Skip the first S/G entry as it points to AAD */
200 		for_each_sg(sg_next(sgout), sg, UINT_MAX, pages) {
201 			if (!sg)
202 				break;
203 			put_page(sg_page(sg));
204 		}
205 	}
206 
207 	kfree(aead_req);
208 
209 	pending = atomic_dec_return(&ctx->decrypt_pending);
210 
211 	if (!pending && READ_ONCE(ctx->async_notify))
212 		complete(&ctx->async_wait.completion);
213 }
214 
215 static int tls_do_decryption(struct sock *sk,
216 			     struct sk_buff *skb,
217 			     struct scatterlist *sgin,
218 			     struct scatterlist *sgout,
219 			     char *iv_recv,
220 			     size_t data_len,
221 			     struct aead_request *aead_req,
222 			     bool async)
223 {
224 	struct tls_context *tls_ctx = tls_get_ctx(sk);
225 	struct tls_prot_info *prot = &tls_ctx->prot_info;
226 	struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
227 	int ret;
228 
229 	aead_request_set_tfm(aead_req, ctx->aead_recv);
230 	aead_request_set_ad(aead_req, prot->aad_size);
231 	aead_request_set_crypt(aead_req, sgin, sgout,
232 			       data_len + prot->tag_size,
233 			       (u8 *)iv_recv);
234 
235 	if (async) {
236 		/* Using skb->sk to push sk through to crypto async callback
237 		 * handler. This allows propagating errors up to the socket
238 		 * if needed. It _must_ be cleared in the async handler
239 		 * before consume_skb is called. We _know_ skb->sk is NULL
240 		 * because it is a clone from strparser.
241 		 */
242 		skb->sk = sk;
243 		aead_request_set_callback(aead_req,
244 					  CRYPTO_TFM_REQ_MAY_BACKLOG,
245 					  tls_decrypt_done, skb);
246 		atomic_inc(&ctx->decrypt_pending);
247 	} else {
248 		aead_request_set_callback(aead_req,
249 					  CRYPTO_TFM_REQ_MAY_BACKLOG,
250 					  crypto_req_done, &ctx->async_wait);
251 	}
252 
253 	ret = crypto_aead_decrypt(aead_req);
254 	if (ret == -EINPROGRESS) {
255 		if (async)
256 			return ret;
257 
258 		ret = crypto_wait_req(ret, &ctx->async_wait);
259 	} else if (ret == -EBADMSG) {
260 		TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSDECRYPTERROR);
261 	}
262 
263 	if (async)
264 		atomic_dec(&ctx->decrypt_pending);
265 
266 	return ret;
267 }
268 
269 static void tls_trim_both_msgs(struct sock *sk, int target_size)
270 {
271 	struct tls_context *tls_ctx = tls_get_ctx(sk);
272 	struct tls_prot_info *prot = &tls_ctx->prot_info;
273 	struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
274 	struct tls_rec *rec = ctx->open_rec;
275 
276 	sk_msg_trim(sk, &rec->msg_plaintext, target_size);
277 	if (target_size > 0)
278 		target_size += prot->overhead_size;
279 	sk_msg_trim(sk, &rec->msg_encrypted, target_size);
280 }
281 
282 static int tls_alloc_encrypted_msg(struct sock *sk, int len)
283 {
284 	struct tls_context *tls_ctx = tls_get_ctx(sk);
285 	struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
286 	struct tls_rec *rec = ctx->open_rec;
287 	struct sk_msg *msg_en = &rec->msg_encrypted;
288 
289 	return sk_msg_alloc(sk, msg_en, len, 0);
290 }
291 
292 static int tls_clone_plaintext_msg(struct sock *sk, int required)
293 {
294 	struct tls_context *tls_ctx = tls_get_ctx(sk);
295 	struct tls_prot_info *prot = &tls_ctx->prot_info;
296 	struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
297 	struct tls_rec *rec = ctx->open_rec;
298 	struct sk_msg *msg_pl = &rec->msg_plaintext;
299 	struct sk_msg *msg_en = &rec->msg_encrypted;
300 	int skip, len;
301 
302 	/* We add page references worth len bytes from encrypted sg
303 	 * at the end of plaintext sg. It is guaranteed that msg_en
304 	 * has enough required room (ensured by caller).
305 	 */
306 	len = required - msg_pl->sg.size;
307 
308 	/* Skip initial bytes in msg_en's data to be able to use
309 	 * same offset of both plain and encrypted data.
310 	 */
311 	skip = prot->prepend_size + msg_pl->sg.size;
312 
313 	return sk_msg_clone(sk, msg_pl, msg_en, skip, len);
314 }
315 
316 static struct tls_rec *tls_get_rec(struct sock *sk)
317 {
318 	struct tls_context *tls_ctx = tls_get_ctx(sk);
319 	struct tls_prot_info *prot = &tls_ctx->prot_info;
320 	struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
321 	struct sk_msg *msg_pl, *msg_en;
322 	struct tls_rec *rec;
323 	int mem_size;
324 
325 	mem_size = sizeof(struct tls_rec) + crypto_aead_reqsize(ctx->aead_send);
326 
327 	rec = kzalloc(mem_size, sk->sk_allocation);
328 	if (!rec)
329 		return NULL;
330 
331 	msg_pl = &rec->msg_plaintext;
332 	msg_en = &rec->msg_encrypted;
333 
334 	sk_msg_init(msg_pl);
335 	sk_msg_init(msg_en);
336 
337 	sg_init_table(rec->sg_aead_in, 2);
338 	sg_set_buf(&rec->sg_aead_in[0], rec->aad_space, prot->aad_size);
339 	sg_unmark_end(&rec->sg_aead_in[1]);
340 
341 	sg_init_table(rec->sg_aead_out, 2);
342 	sg_set_buf(&rec->sg_aead_out[0], rec->aad_space, prot->aad_size);
343 	sg_unmark_end(&rec->sg_aead_out[1]);
344 
345 	return rec;
346 }
347 
348 static void tls_free_rec(struct sock *sk, struct tls_rec *rec)
349 {
350 	sk_msg_free(sk, &rec->msg_encrypted);
351 	sk_msg_free(sk, &rec->msg_plaintext);
352 	kfree(rec);
353 }
354 
355 static void tls_free_open_rec(struct sock *sk)
356 {
357 	struct tls_context *tls_ctx = tls_get_ctx(sk);
358 	struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
359 	struct tls_rec *rec = ctx->open_rec;
360 
361 	if (rec) {
362 		tls_free_rec(sk, rec);
363 		ctx->open_rec = NULL;
364 	}
365 }
366 
367 int tls_tx_records(struct sock *sk, int flags)
368 {
369 	struct tls_context *tls_ctx = tls_get_ctx(sk);
370 	struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
371 	struct tls_rec *rec, *tmp;
372 	struct sk_msg *msg_en;
373 	int tx_flags, rc = 0;
374 
375 	if (tls_is_partially_sent_record(tls_ctx)) {
376 		rec = list_first_entry(&ctx->tx_list,
377 				       struct tls_rec, list);
378 
379 		if (flags == -1)
380 			tx_flags = rec->tx_flags;
381 		else
382 			tx_flags = flags;
383 
384 		rc = tls_push_partial_record(sk, tls_ctx, tx_flags);
385 		if (rc)
386 			goto tx_err;
387 
388 		/* Full record has been transmitted.
389 		 * Remove the head of tx_list
390 		 */
391 		list_del(&rec->list);
392 		sk_msg_free(sk, &rec->msg_plaintext);
393 		kfree(rec);
394 	}
395 
396 	/* Tx all ready records */
397 	list_for_each_entry_safe(rec, tmp, &ctx->tx_list, list) {
398 		if (READ_ONCE(rec->tx_ready)) {
399 			if (flags == -1)
400 				tx_flags = rec->tx_flags;
401 			else
402 				tx_flags = flags;
403 
404 			msg_en = &rec->msg_encrypted;
405 			rc = tls_push_sg(sk, tls_ctx,
406 					 &msg_en->sg.data[msg_en->sg.curr],
407 					 0, tx_flags);
408 			if (rc)
409 				goto tx_err;
410 
411 			list_del(&rec->list);
412 			sk_msg_free(sk, &rec->msg_plaintext);
413 			kfree(rec);
414 		} else {
415 			break;
416 		}
417 	}
418 
419 tx_err:
420 	if (rc < 0 && rc != -EAGAIN)
421 		tls_err_abort(sk, EBADMSG);
422 
423 	return rc;
424 }
425 
426 static void tls_encrypt_done(struct crypto_async_request *req, int err)
427 {
428 	struct aead_request *aead_req = (struct aead_request *)req;
429 	struct sock *sk = req->data;
430 	struct tls_context *tls_ctx = tls_get_ctx(sk);
431 	struct tls_prot_info *prot = &tls_ctx->prot_info;
432 	struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
433 	struct scatterlist *sge;
434 	struct sk_msg *msg_en;
435 	struct tls_rec *rec;
436 	bool ready = false;
437 	int pending;
438 
439 	rec = container_of(aead_req, struct tls_rec, aead_req);
440 	msg_en = &rec->msg_encrypted;
441 
442 	sge = sk_msg_elem(msg_en, msg_en->sg.curr);
443 	sge->offset -= prot->prepend_size;
444 	sge->length += prot->prepend_size;
445 
446 	/* Check if error is previously set on socket */
447 	if (err || sk->sk_err) {
448 		rec = NULL;
449 
450 		/* If err is already set on socket, return the same code */
451 		if (sk->sk_err) {
452 			ctx->async_wait.err = sk->sk_err;
453 		} else {
454 			ctx->async_wait.err = err;
455 			tls_err_abort(sk, err);
456 		}
457 	}
458 
459 	if (rec) {
460 		struct tls_rec *first_rec;
461 
462 		/* Mark the record as ready for transmission */
463 		smp_store_mb(rec->tx_ready, true);
464 
465 		/* If received record is at head of tx_list, schedule tx */
466 		first_rec = list_first_entry(&ctx->tx_list,
467 					     struct tls_rec, list);
468 		if (rec == first_rec)
469 			ready = true;
470 	}
471 
472 	pending = atomic_dec_return(&ctx->encrypt_pending);
473 
474 	if (!pending && READ_ONCE(ctx->async_notify))
475 		complete(&ctx->async_wait.completion);
476 
477 	if (!ready)
478 		return;
479 
480 	/* Schedule the transmission */
481 	if (!test_and_set_bit(BIT_TX_SCHEDULED, &ctx->tx_bitmask))
482 		schedule_delayed_work(&ctx->tx_work.work, 1);
483 }
484 
485 static int tls_do_encryption(struct sock *sk,
486 			     struct tls_context *tls_ctx,
487 			     struct tls_sw_context_tx *ctx,
488 			     struct aead_request *aead_req,
489 			     size_t data_len, u32 start)
490 {
491 	struct tls_prot_info *prot = &tls_ctx->prot_info;
492 	struct tls_rec *rec = ctx->open_rec;
493 	struct sk_msg *msg_en = &rec->msg_encrypted;
494 	struct scatterlist *sge = sk_msg_elem(msg_en, start);
495 	int rc, iv_offset = 0;
496 
497 	/* For CCM based ciphers, first byte of IV is a constant */
498 	if (prot->cipher_type == TLS_CIPHER_AES_CCM_128) {
499 		rec->iv_data[0] = TLS_AES_CCM_IV_B0_BYTE;
500 		iv_offset = 1;
501 	}
502 
503 	memcpy(&rec->iv_data[iv_offset], tls_ctx->tx.iv,
504 	       prot->iv_size + prot->salt_size);
505 
506 	xor_iv_with_seq(prot->version, rec->iv_data, tls_ctx->tx.rec_seq);
507 
508 	sge->offset += prot->prepend_size;
509 	sge->length -= prot->prepend_size;
510 
511 	msg_en->sg.curr = start;
512 
513 	aead_request_set_tfm(aead_req, ctx->aead_send);
514 	aead_request_set_ad(aead_req, prot->aad_size);
515 	aead_request_set_crypt(aead_req, rec->sg_aead_in,
516 			       rec->sg_aead_out,
517 			       data_len, rec->iv_data);
518 
519 	aead_request_set_callback(aead_req, CRYPTO_TFM_REQ_MAY_BACKLOG,
520 				  tls_encrypt_done, sk);
521 
522 	/* Add the record in tx_list */
523 	list_add_tail((struct list_head *)&rec->list, &ctx->tx_list);
524 	atomic_inc(&ctx->encrypt_pending);
525 
526 	rc = crypto_aead_encrypt(aead_req);
527 	if (!rc || rc != -EINPROGRESS) {
528 		atomic_dec(&ctx->encrypt_pending);
529 		sge->offset -= prot->prepend_size;
530 		sge->length += prot->prepend_size;
531 	}
532 
533 	if (!rc) {
534 		WRITE_ONCE(rec->tx_ready, true);
535 	} else if (rc != -EINPROGRESS) {
536 		list_del(&rec->list);
537 		return rc;
538 	}
539 
540 	/* Unhook the record from context if encryption is not failure */
541 	ctx->open_rec = NULL;
542 	tls_advance_record_sn(sk, prot, &tls_ctx->tx);
543 	return rc;
544 }
545 
546 static int tls_split_open_record(struct sock *sk, struct tls_rec *from,
547 				 struct tls_rec **to, struct sk_msg *msg_opl,
548 				 struct sk_msg *msg_oen, u32 split_point,
549 				 u32 tx_overhead_size, u32 *orig_end)
550 {
551 	u32 i, j, bytes = 0, apply = msg_opl->apply_bytes;
552 	struct scatterlist *sge, *osge, *nsge;
553 	u32 orig_size = msg_opl->sg.size;
554 	struct scatterlist tmp = { };
555 	struct sk_msg *msg_npl;
556 	struct tls_rec *new;
557 	int ret;
558 
559 	new = tls_get_rec(sk);
560 	if (!new)
561 		return -ENOMEM;
562 	ret = sk_msg_alloc(sk, &new->msg_encrypted, msg_opl->sg.size +
563 			   tx_overhead_size, 0);
564 	if (ret < 0) {
565 		tls_free_rec(sk, new);
566 		return ret;
567 	}
568 
569 	*orig_end = msg_opl->sg.end;
570 	i = msg_opl->sg.start;
571 	sge = sk_msg_elem(msg_opl, i);
572 	while (apply && sge->length) {
573 		if (sge->length > apply) {
574 			u32 len = sge->length - apply;
575 
576 			get_page(sg_page(sge));
577 			sg_set_page(&tmp, sg_page(sge), len,
578 				    sge->offset + apply);
579 			sge->length = apply;
580 			bytes += apply;
581 			apply = 0;
582 		} else {
583 			apply -= sge->length;
584 			bytes += sge->length;
585 		}
586 
587 		sk_msg_iter_var_next(i);
588 		if (i == msg_opl->sg.end)
589 			break;
590 		sge = sk_msg_elem(msg_opl, i);
591 	}
592 
593 	msg_opl->sg.end = i;
594 	msg_opl->sg.curr = i;
595 	msg_opl->sg.copybreak = 0;
596 	msg_opl->apply_bytes = 0;
597 	msg_opl->sg.size = bytes;
598 
599 	msg_npl = &new->msg_plaintext;
600 	msg_npl->apply_bytes = apply;
601 	msg_npl->sg.size = orig_size - bytes;
602 
603 	j = msg_npl->sg.start;
604 	nsge = sk_msg_elem(msg_npl, j);
605 	if (tmp.length) {
606 		memcpy(nsge, &tmp, sizeof(*nsge));
607 		sk_msg_iter_var_next(j);
608 		nsge = sk_msg_elem(msg_npl, j);
609 	}
610 
611 	osge = sk_msg_elem(msg_opl, i);
612 	while (osge->length) {
613 		memcpy(nsge, osge, sizeof(*nsge));
614 		sg_unmark_end(nsge);
615 		sk_msg_iter_var_next(i);
616 		sk_msg_iter_var_next(j);
617 		if (i == *orig_end)
618 			break;
619 		osge = sk_msg_elem(msg_opl, i);
620 		nsge = sk_msg_elem(msg_npl, j);
621 	}
622 
623 	msg_npl->sg.end = j;
624 	msg_npl->sg.curr = j;
625 	msg_npl->sg.copybreak = 0;
626 
627 	*to = new;
628 	return 0;
629 }
630 
631 static void tls_merge_open_record(struct sock *sk, struct tls_rec *to,
632 				  struct tls_rec *from, u32 orig_end)
633 {
634 	struct sk_msg *msg_npl = &from->msg_plaintext;
635 	struct sk_msg *msg_opl = &to->msg_plaintext;
636 	struct scatterlist *osge, *nsge;
637 	u32 i, j;
638 
639 	i = msg_opl->sg.end;
640 	sk_msg_iter_var_prev(i);
641 	j = msg_npl->sg.start;
642 
643 	osge = sk_msg_elem(msg_opl, i);
644 	nsge = sk_msg_elem(msg_npl, j);
645 
646 	if (sg_page(osge) == sg_page(nsge) &&
647 	    osge->offset + osge->length == nsge->offset) {
648 		osge->length += nsge->length;
649 		put_page(sg_page(nsge));
650 	}
651 
652 	msg_opl->sg.end = orig_end;
653 	msg_opl->sg.curr = orig_end;
654 	msg_opl->sg.copybreak = 0;
655 	msg_opl->apply_bytes = msg_opl->sg.size + msg_npl->sg.size;
656 	msg_opl->sg.size += msg_npl->sg.size;
657 
658 	sk_msg_free(sk, &to->msg_encrypted);
659 	sk_msg_xfer_full(&to->msg_encrypted, &from->msg_encrypted);
660 
661 	kfree(from);
662 }
663 
664 static int tls_push_record(struct sock *sk, int flags,
665 			   unsigned char record_type)
666 {
667 	struct tls_context *tls_ctx = tls_get_ctx(sk);
668 	struct tls_prot_info *prot = &tls_ctx->prot_info;
669 	struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
670 	struct tls_rec *rec = ctx->open_rec, *tmp = NULL;
671 	u32 i, split_point, uninitialized_var(orig_end);
672 	struct sk_msg *msg_pl, *msg_en;
673 	struct aead_request *req;
674 	bool split;
675 	int rc;
676 
677 	if (!rec)
678 		return 0;
679 
680 	msg_pl = &rec->msg_plaintext;
681 	msg_en = &rec->msg_encrypted;
682 
683 	split_point = msg_pl->apply_bytes;
684 	split = split_point && split_point < msg_pl->sg.size;
685 	if (split) {
686 		rc = tls_split_open_record(sk, rec, &tmp, msg_pl, msg_en,
687 					   split_point, prot->overhead_size,
688 					   &orig_end);
689 		if (rc < 0)
690 			return rc;
691 		sk_msg_trim(sk, msg_en, msg_pl->sg.size +
692 			    prot->overhead_size);
693 	}
694 
695 	rec->tx_flags = flags;
696 	req = &rec->aead_req;
697 
698 	i = msg_pl->sg.end;
699 	sk_msg_iter_var_prev(i);
700 
701 	rec->content_type = record_type;
702 	if (prot->version == TLS_1_3_VERSION) {
703 		/* Add content type to end of message.  No padding added */
704 		sg_set_buf(&rec->sg_content_type, &rec->content_type, 1);
705 		sg_mark_end(&rec->sg_content_type);
706 		sg_chain(msg_pl->sg.data, msg_pl->sg.end + 1,
707 			 &rec->sg_content_type);
708 	} else {
709 		sg_mark_end(sk_msg_elem(msg_pl, i));
710 	}
711 
712 	i = msg_pl->sg.start;
713 	sg_chain(rec->sg_aead_in, 2, &msg_pl->sg.data[i]);
714 
715 	i = msg_en->sg.end;
716 	sk_msg_iter_var_prev(i);
717 	sg_mark_end(sk_msg_elem(msg_en, i));
718 
719 	i = msg_en->sg.start;
720 	sg_chain(rec->sg_aead_out, 2, &msg_en->sg.data[i]);
721 
722 	tls_make_aad(rec->aad_space, msg_pl->sg.size + prot->tail_size,
723 		     tls_ctx->tx.rec_seq, prot->rec_seq_size,
724 		     record_type, prot->version);
725 
726 	tls_fill_prepend(tls_ctx,
727 			 page_address(sg_page(&msg_en->sg.data[i])) +
728 			 msg_en->sg.data[i].offset,
729 			 msg_pl->sg.size + prot->tail_size,
730 			 record_type, prot->version);
731 
732 	tls_ctx->pending_open_record_frags = false;
733 
734 	rc = tls_do_encryption(sk, tls_ctx, ctx, req,
735 			       msg_pl->sg.size + prot->tail_size, i);
736 	if (rc < 0) {
737 		if (rc != -EINPROGRESS) {
738 			tls_err_abort(sk, EBADMSG);
739 			if (split) {
740 				tls_ctx->pending_open_record_frags = true;
741 				tls_merge_open_record(sk, rec, tmp, orig_end);
742 			}
743 		}
744 		ctx->async_capable = 1;
745 		return rc;
746 	} else if (split) {
747 		msg_pl = &tmp->msg_plaintext;
748 		msg_en = &tmp->msg_encrypted;
749 		sk_msg_trim(sk, msg_en, msg_pl->sg.size + prot->overhead_size);
750 		tls_ctx->pending_open_record_frags = true;
751 		ctx->open_rec = tmp;
752 	}
753 
754 	return tls_tx_records(sk, flags);
755 }
756 
757 static int bpf_exec_tx_verdict(struct sk_msg *msg, struct sock *sk,
758 			       bool full_record, u8 record_type,
759 			       size_t *copied, int flags)
760 {
761 	struct tls_context *tls_ctx = tls_get_ctx(sk);
762 	struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
763 	struct sk_msg msg_redir = { };
764 	struct sk_psock *psock;
765 	struct sock *sk_redir;
766 	struct tls_rec *rec;
767 	bool enospc, policy;
768 	int err = 0, send;
769 	u32 delta = 0;
770 
771 	policy = !(flags & MSG_SENDPAGE_NOPOLICY);
772 	psock = sk_psock_get(sk);
773 	if (!psock || !policy) {
774 		err = tls_push_record(sk, flags, record_type);
775 		if (err) {
776 			*copied -= sk_msg_free(sk, msg);
777 			tls_free_open_rec(sk);
778 		}
779 		return err;
780 	}
781 more_data:
782 	enospc = sk_msg_full(msg);
783 	if (psock->eval == __SK_NONE) {
784 		delta = msg->sg.size;
785 		psock->eval = sk_psock_msg_verdict(sk, psock, msg);
786 		if (delta < msg->sg.size)
787 			delta -= msg->sg.size;
788 		else
789 			delta = 0;
790 	}
791 	if (msg->cork_bytes && msg->cork_bytes > msg->sg.size &&
792 	    !enospc && !full_record) {
793 		err = -ENOSPC;
794 		goto out_err;
795 	}
796 	msg->cork_bytes = 0;
797 	send = msg->sg.size;
798 	if (msg->apply_bytes && msg->apply_bytes < send)
799 		send = msg->apply_bytes;
800 
801 	switch (psock->eval) {
802 	case __SK_PASS:
803 		err = tls_push_record(sk, flags, record_type);
804 		if (err < 0) {
805 			*copied -= sk_msg_free(sk, msg);
806 			tls_free_open_rec(sk);
807 			goto out_err;
808 		}
809 		break;
810 	case __SK_REDIRECT:
811 		sk_redir = psock->sk_redir;
812 		memcpy(&msg_redir, msg, sizeof(*msg));
813 		if (msg->apply_bytes < send)
814 			msg->apply_bytes = 0;
815 		else
816 			msg->apply_bytes -= send;
817 		sk_msg_return_zero(sk, msg, send);
818 		msg->sg.size -= send;
819 		release_sock(sk);
820 		err = tcp_bpf_sendmsg_redir(sk_redir, &msg_redir, send, flags);
821 		lock_sock(sk);
822 		if (err < 0) {
823 			*copied -= sk_msg_free_nocharge(sk, &msg_redir);
824 			msg->sg.size = 0;
825 		}
826 		if (msg->sg.size == 0)
827 			tls_free_open_rec(sk);
828 		break;
829 	case __SK_DROP:
830 	default:
831 		sk_msg_free_partial(sk, msg, send);
832 		if (msg->apply_bytes < send)
833 			msg->apply_bytes = 0;
834 		else
835 			msg->apply_bytes -= send;
836 		if (msg->sg.size == 0)
837 			tls_free_open_rec(sk);
838 		*copied -= (send + delta);
839 		err = -EACCES;
840 	}
841 
842 	if (likely(!err)) {
843 		bool reset_eval = !ctx->open_rec;
844 
845 		rec = ctx->open_rec;
846 		if (rec) {
847 			msg = &rec->msg_plaintext;
848 			if (!msg->apply_bytes)
849 				reset_eval = true;
850 		}
851 		if (reset_eval) {
852 			psock->eval = __SK_NONE;
853 			if (psock->sk_redir) {
854 				sock_put(psock->sk_redir);
855 				psock->sk_redir = NULL;
856 			}
857 		}
858 		if (rec)
859 			goto more_data;
860 	}
861  out_err:
862 	sk_psock_put(sk, psock);
863 	return err;
864 }
865 
866 static int tls_sw_push_pending_record(struct sock *sk, int flags)
867 {
868 	struct tls_context *tls_ctx = tls_get_ctx(sk);
869 	struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
870 	struct tls_rec *rec = ctx->open_rec;
871 	struct sk_msg *msg_pl;
872 	size_t copied;
873 
874 	if (!rec)
875 		return 0;
876 
877 	msg_pl = &rec->msg_plaintext;
878 	copied = msg_pl->sg.size;
879 	if (!copied)
880 		return 0;
881 
882 	return bpf_exec_tx_verdict(msg_pl, sk, true, TLS_RECORD_TYPE_DATA,
883 				   &copied, flags);
884 }
885 
886 int tls_sw_sendmsg(struct sock *sk, struct msghdr *msg, size_t size)
887 {
888 	long timeo = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT);
889 	struct tls_context *tls_ctx = tls_get_ctx(sk);
890 	struct tls_prot_info *prot = &tls_ctx->prot_info;
891 	struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
892 	bool async_capable = ctx->async_capable;
893 	unsigned char record_type = TLS_RECORD_TYPE_DATA;
894 	bool is_kvec = iov_iter_is_kvec(&msg->msg_iter);
895 	bool eor = !(msg->msg_flags & MSG_MORE);
896 	size_t try_to_copy, copied = 0;
897 	struct sk_msg *msg_pl, *msg_en;
898 	struct tls_rec *rec;
899 	int required_size;
900 	int num_async = 0;
901 	bool full_record;
902 	int record_room;
903 	int num_zc = 0;
904 	int orig_size;
905 	int ret = 0;
906 
907 	if (msg->msg_flags & ~(MSG_MORE | MSG_DONTWAIT | MSG_NOSIGNAL))
908 		return -EOPNOTSUPP;
909 
910 	mutex_lock(&tls_ctx->tx_lock);
911 	lock_sock(sk);
912 
913 	if (unlikely(msg->msg_controllen)) {
914 		ret = tls_proccess_cmsg(sk, msg, &record_type);
915 		if (ret) {
916 			if (ret == -EINPROGRESS)
917 				num_async++;
918 			else if (ret != -EAGAIN)
919 				goto send_end;
920 		}
921 	}
922 
923 	while (msg_data_left(msg)) {
924 		if (sk->sk_err) {
925 			ret = -sk->sk_err;
926 			goto send_end;
927 		}
928 
929 		if (ctx->open_rec)
930 			rec = ctx->open_rec;
931 		else
932 			rec = ctx->open_rec = tls_get_rec(sk);
933 		if (!rec) {
934 			ret = -ENOMEM;
935 			goto send_end;
936 		}
937 
938 		msg_pl = &rec->msg_plaintext;
939 		msg_en = &rec->msg_encrypted;
940 
941 		orig_size = msg_pl->sg.size;
942 		full_record = false;
943 		try_to_copy = msg_data_left(msg);
944 		record_room = TLS_MAX_PAYLOAD_SIZE - msg_pl->sg.size;
945 		if (try_to_copy >= record_room) {
946 			try_to_copy = record_room;
947 			full_record = true;
948 		}
949 
950 		required_size = msg_pl->sg.size + try_to_copy +
951 				prot->overhead_size;
952 
953 		if (!sk_stream_memory_free(sk))
954 			goto wait_for_sndbuf;
955 
956 alloc_encrypted:
957 		ret = tls_alloc_encrypted_msg(sk, required_size);
958 		if (ret) {
959 			if (ret != -ENOSPC)
960 				goto wait_for_memory;
961 
962 			/* Adjust try_to_copy according to the amount that was
963 			 * actually allocated. The difference is due
964 			 * to max sg elements limit
965 			 */
966 			try_to_copy -= required_size - msg_en->sg.size;
967 			full_record = true;
968 		}
969 
970 		if (!is_kvec && (full_record || eor) && !async_capable) {
971 			u32 first = msg_pl->sg.end;
972 
973 			ret = sk_msg_zerocopy_from_iter(sk, &msg->msg_iter,
974 							msg_pl, try_to_copy);
975 			if (ret)
976 				goto fallback_to_reg_send;
977 
978 			num_zc++;
979 			copied += try_to_copy;
980 
981 			sk_msg_sg_copy_set(msg_pl, first);
982 			ret = bpf_exec_tx_verdict(msg_pl, sk, full_record,
983 						  record_type, &copied,
984 						  msg->msg_flags);
985 			if (ret) {
986 				if (ret == -EINPROGRESS)
987 					num_async++;
988 				else if (ret == -ENOMEM)
989 					goto wait_for_memory;
990 				else if (ctx->open_rec && ret == -ENOSPC)
991 					goto rollback_iter;
992 				else if (ret != -EAGAIN)
993 					goto send_end;
994 			}
995 			continue;
996 rollback_iter:
997 			copied -= try_to_copy;
998 			sk_msg_sg_copy_clear(msg_pl, first);
999 			iov_iter_revert(&msg->msg_iter,
1000 					msg_pl->sg.size - orig_size);
1001 fallback_to_reg_send:
1002 			sk_msg_trim(sk, msg_pl, orig_size);
1003 		}
1004 
1005 		required_size = msg_pl->sg.size + try_to_copy;
1006 
1007 		ret = tls_clone_plaintext_msg(sk, required_size);
1008 		if (ret) {
1009 			if (ret != -ENOSPC)
1010 				goto send_end;
1011 
1012 			/* Adjust try_to_copy according to the amount that was
1013 			 * actually allocated. The difference is due
1014 			 * to max sg elements limit
1015 			 */
1016 			try_to_copy -= required_size - msg_pl->sg.size;
1017 			full_record = true;
1018 			sk_msg_trim(sk, msg_en,
1019 				    msg_pl->sg.size + prot->overhead_size);
1020 		}
1021 
1022 		if (try_to_copy) {
1023 			ret = sk_msg_memcopy_from_iter(sk, &msg->msg_iter,
1024 						       msg_pl, try_to_copy);
1025 			if (ret < 0)
1026 				goto trim_sgl;
1027 		}
1028 
1029 		/* Open records defined only if successfully copied, otherwise
1030 		 * we would trim the sg but not reset the open record frags.
1031 		 */
1032 		tls_ctx->pending_open_record_frags = true;
1033 		copied += try_to_copy;
1034 		if (full_record || eor) {
1035 			ret = bpf_exec_tx_verdict(msg_pl, sk, full_record,
1036 						  record_type, &copied,
1037 						  msg->msg_flags);
1038 			if (ret) {
1039 				if (ret == -EINPROGRESS)
1040 					num_async++;
1041 				else if (ret == -ENOMEM)
1042 					goto wait_for_memory;
1043 				else if (ret != -EAGAIN) {
1044 					if (ret == -ENOSPC)
1045 						ret = 0;
1046 					goto send_end;
1047 				}
1048 			}
1049 		}
1050 
1051 		continue;
1052 
1053 wait_for_sndbuf:
1054 		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1055 wait_for_memory:
1056 		ret = sk_stream_wait_memory(sk, &timeo);
1057 		if (ret) {
1058 trim_sgl:
1059 			if (ctx->open_rec)
1060 				tls_trim_both_msgs(sk, orig_size);
1061 			goto send_end;
1062 		}
1063 
1064 		if (ctx->open_rec && msg_en->sg.size < required_size)
1065 			goto alloc_encrypted;
1066 	}
1067 
1068 	if (!num_async) {
1069 		goto send_end;
1070 	} else if (num_zc) {
1071 		/* Wait for pending encryptions to get completed */
1072 		smp_store_mb(ctx->async_notify, true);
1073 
1074 		if (atomic_read(&ctx->encrypt_pending))
1075 			crypto_wait_req(-EINPROGRESS, &ctx->async_wait);
1076 		else
1077 			reinit_completion(&ctx->async_wait.completion);
1078 
1079 		WRITE_ONCE(ctx->async_notify, false);
1080 
1081 		if (ctx->async_wait.err) {
1082 			ret = ctx->async_wait.err;
1083 			copied = 0;
1084 		}
1085 	}
1086 
1087 	/* Transmit if any encryptions have completed */
1088 	if (test_and_clear_bit(BIT_TX_SCHEDULED, &ctx->tx_bitmask)) {
1089 		cancel_delayed_work(&ctx->tx_work.work);
1090 		tls_tx_records(sk, msg->msg_flags);
1091 	}
1092 
1093 send_end:
1094 	ret = sk_stream_error(sk, msg->msg_flags, ret);
1095 
1096 	release_sock(sk);
1097 	mutex_unlock(&tls_ctx->tx_lock);
1098 	return copied ? copied : ret;
1099 }
1100 
1101 static int tls_sw_do_sendpage(struct sock *sk, struct page *page,
1102 			      int offset, size_t size, int flags)
1103 {
1104 	long timeo = sock_sndtimeo(sk, flags & MSG_DONTWAIT);
1105 	struct tls_context *tls_ctx = tls_get_ctx(sk);
1106 	struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
1107 	struct tls_prot_info *prot = &tls_ctx->prot_info;
1108 	unsigned char record_type = TLS_RECORD_TYPE_DATA;
1109 	struct sk_msg *msg_pl;
1110 	struct tls_rec *rec;
1111 	int num_async = 0;
1112 	size_t copied = 0;
1113 	bool full_record;
1114 	int record_room;
1115 	int ret = 0;
1116 	bool eor;
1117 
1118 	eor = !(flags & (MSG_MORE | MSG_SENDPAGE_NOTLAST));
1119 	sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);
1120 
1121 	/* Call the sk_stream functions to manage the sndbuf mem. */
1122 	while (size > 0) {
1123 		size_t copy, required_size;
1124 
1125 		if (sk->sk_err) {
1126 			ret = -sk->sk_err;
1127 			goto sendpage_end;
1128 		}
1129 
1130 		if (ctx->open_rec)
1131 			rec = ctx->open_rec;
1132 		else
1133 			rec = ctx->open_rec = tls_get_rec(sk);
1134 		if (!rec) {
1135 			ret = -ENOMEM;
1136 			goto sendpage_end;
1137 		}
1138 
1139 		msg_pl = &rec->msg_plaintext;
1140 
1141 		full_record = false;
1142 		record_room = TLS_MAX_PAYLOAD_SIZE - msg_pl->sg.size;
1143 		copy = size;
1144 		if (copy >= record_room) {
1145 			copy = record_room;
1146 			full_record = true;
1147 		}
1148 
1149 		required_size = msg_pl->sg.size + copy + prot->overhead_size;
1150 
1151 		if (!sk_stream_memory_free(sk))
1152 			goto wait_for_sndbuf;
1153 alloc_payload:
1154 		ret = tls_alloc_encrypted_msg(sk, required_size);
1155 		if (ret) {
1156 			if (ret != -ENOSPC)
1157 				goto wait_for_memory;
1158 
1159 			/* Adjust copy according to the amount that was
1160 			 * actually allocated. The difference is due
1161 			 * to max sg elements limit
1162 			 */
1163 			copy -= required_size - msg_pl->sg.size;
1164 			full_record = true;
1165 		}
1166 
1167 		sk_msg_page_add(msg_pl, page, copy, offset);
1168 		sk_mem_charge(sk, copy);
1169 
1170 		offset += copy;
1171 		size -= copy;
1172 		copied += copy;
1173 
1174 		tls_ctx->pending_open_record_frags = true;
1175 		if (full_record || eor || sk_msg_full(msg_pl)) {
1176 			ret = bpf_exec_tx_verdict(msg_pl, sk, full_record,
1177 						  record_type, &copied, flags);
1178 			if (ret) {
1179 				if (ret == -EINPROGRESS)
1180 					num_async++;
1181 				else if (ret == -ENOMEM)
1182 					goto wait_for_memory;
1183 				else if (ret != -EAGAIN) {
1184 					if (ret == -ENOSPC)
1185 						ret = 0;
1186 					goto sendpage_end;
1187 				}
1188 			}
1189 		}
1190 		continue;
1191 wait_for_sndbuf:
1192 		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1193 wait_for_memory:
1194 		ret = sk_stream_wait_memory(sk, &timeo);
1195 		if (ret) {
1196 			if (ctx->open_rec)
1197 				tls_trim_both_msgs(sk, msg_pl->sg.size);
1198 			goto sendpage_end;
1199 		}
1200 
1201 		if (ctx->open_rec)
1202 			goto alloc_payload;
1203 	}
1204 
1205 	if (num_async) {
1206 		/* Transmit if any encryptions have completed */
1207 		if (test_and_clear_bit(BIT_TX_SCHEDULED, &ctx->tx_bitmask)) {
1208 			cancel_delayed_work(&ctx->tx_work.work);
1209 			tls_tx_records(sk, flags);
1210 		}
1211 	}
1212 sendpage_end:
1213 	ret = sk_stream_error(sk, flags, ret);
1214 	return copied ? copied : ret;
1215 }
1216 
1217 int tls_sw_sendpage_locked(struct sock *sk, struct page *page,
1218 			   int offset, size_t size, int flags)
1219 {
1220 	if (flags & ~(MSG_MORE | MSG_DONTWAIT | MSG_NOSIGNAL |
1221 		      MSG_SENDPAGE_NOTLAST | MSG_SENDPAGE_NOPOLICY |
1222 		      MSG_NO_SHARED_FRAGS))
1223 		return -EOPNOTSUPP;
1224 
1225 	return tls_sw_do_sendpage(sk, page, offset, size, flags);
1226 }
1227 
1228 int tls_sw_sendpage(struct sock *sk, struct page *page,
1229 		    int offset, size_t size, int flags)
1230 {
1231 	struct tls_context *tls_ctx = tls_get_ctx(sk);
1232 	int ret;
1233 
1234 	if (flags & ~(MSG_MORE | MSG_DONTWAIT | MSG_NOSIGNAL |
1235 		      MSG_SENDPAGE_NOTLAST | MSG_SENDPAGE_NOPOLICY))
1236 		return -EOPNOTSUPP;
1237 
1238 	mutex_lock(&tls_ctx->tx_lock);
1239 	lock_sock(sk);
1240 	ret = tls_sw_do_sendpage(sk, page, offset, size, flags);
1241 	release_sock(sk);
1242 	mutex_unlock(&tls_ctx->tx_lock);
1243 	return ret;
1244 }
1245 
1246 static struct sk_buff *tls_wait_data(struct sock *sk, struct sk_psock *psock,
1247 				     int flags, long timeo, int *err)
1248 {
1249 	struct tls_context *tls_ctx = tls_get_ctx(sk);
1250 	struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
1251 	struct sk_buff *skb;
1252 	DEFINE_WAIT_FUNC(wait, woken_wake_function);
1253 
1254 	while (!(skb = ctx->recv_pkt) && sk_psock_queue_empty(psock)) {
1255 		if (sk->sk_err) {
1256 			*err = sock_error(sk);
1257 			return NULL;
1258 		}
1259 
1260 		if (sk->sk_shutdown & RCV_SHUTDOWN)
1261 			return NULL;
1262 
1263 		if (sock_flag(sk, SOCK_DONE))
1264 			return NULL;
1265 
1266 		if ((flags & MSG_DONTWAIT) || !timeo) {
1267 			*err = -EAGAIN;
1268 			return NULL;
1269 		}
1270 
1271 		add_wait_queue(sk_sleep(sk), &wait);
1272 		sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk);
1273 		sk_wait_event(sk, &timeo,
1274 			      ctx->recv_pkt != skb ||
1275 			      !sk_psock_queue_empty(psock),
1276 			      &wait);
1277 		sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk);
1278 		remove_wait_queue(sk_sleep(sk), &wait);
1279 
1280 		/* Handle signals */
1281 		if (signal_pending(current)) {
1282 			*err = sock_intr_errno(timeo);
1283 			return NULL;
1284 		}
1285 	}
1286 
1287 	return skb;
1288 }
1289 
1290 static int tls_setup_from_iter(struct sock *sk, struct iov_iter *from,
1291 			       int length, int *pages_used,
1292 			       unsigned int *size_used,
1293 			       struct scatterlist *to,
1294 			       int to_max_pages)
1295 {
1296 	int rc = 0, i = 0, num_elem = *pages_used, maxpages;
1297 	struct page *pages[MAX_SKB_FRAGS];
1298 	unsigned int size = *size_used;
1299 	ssize_t copied, use;
1300 	size_t offset;
1301 
1302 	while (length > 0) {
1303 		i = 0;
1304 		maxpages = to_max_pages - num_elem;
1305 		if (maxpages == 0) {
1306 			rc = -EFAULT;
1307 			goto out;
1308 		}
1309 		copied = iov_iter_get_pages(from, pages,
1310 					    length,
1311 					    maxpages, &offset);
1312 		if (copied <= 0) {
1313 			rc = -EFAULT;
1314 			goto out;
1315 		}
1316 
1317 		iov_iter_advance(from, copied);
1318 
1319 		length -= copied;
1320 		size += copied;
1321 		while (copied) {
1322 			use = min_t(int, copied, PAGE_SIZE - offset);
1323 
1324 			sg_set_page(&to[num_elem],
1325 				    pages[i], use, offset);
1326 			sg_unmark_end(&to[num_elem]);
1327 			/* We do not uncharge memory from this API */
1328 
1329 			offset = 0;
1330 			copied -= use;
1331 
1332 			i++;
1333 			num_elem++;
1334 		}
1335 	}
1336 	/* Mark the end in the last sg entry if newly added */
1337 	if (num_elem > *pages_used)
1338 		sg_mark_end(&to[num_elem - 1]);
1339 out:
1340 	if (rc)
1341 		iov_iter_revert(from, size - *size_used);
1342 	*size_used = size;
1343 	*pages_used = num_elem;
1344 
1345 	return rc;
1346 }
1347 
1348 /* This function decrypts the input skb into either out_iov or in out_sg
1349  * or in skb buffers itself. The input parameter 'zc' indicates if
1350  * zero-copy mode needs to be tried or not. With zero-copy mode, either
1351  * out_iov or out_sg must be non-NULL. In case both out_iov and out_sg are
1352  * NULL, then the decryption happens inside skb buffers itself, i.e.
1353  * zero-copy gets disabled and 'zc' is updated.
1354  */
1355 
1356 static int decrypt_internal(struct sock *sk, struct sk_buff *skb,
1357 			    struct iov_iter *out_iov,
1358 			    struct scatterlist *out_sg,
1359 			    int *chunk, bool *zc, bool async)
1360 {
1361 	struct tls_context *tls_ctx = tls_get_ctx(sk);
1362 	struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
1363 	struct tls_prot_info *prot = &tls_ctx->prot_info;
1364 	struct strp_msg *rxm = strp_msg(skb);
1365 	int n_sgin, n_sgout, nsg, mem_size, aead_size, err, pages = 0;
1366 	struct aead_request *aead_req;
1367 	struct sk_buff *unused;
1368 	u8 *aad, *iv, *mem = NULL;
1369 	struct scatterlist *sgin = NULL;
1370 	struct scatterlist *sgout = NULL;
1371 	const int data_len = rxm->full_len - prot->overhead_size +
1372 			     prot->tail_size;
1373 	int iv_offset = 0;
1374 
1375 	if (*zc && (out_iov || out_sg)) {
1376 		if (out_iov)
1377 			n_sgout = iov_iter_npages(out_iov, INT_MAX) + 1;
1378 		else
1379 			n_sgout = sg_nents(out_sg);
1380 		n_sgin = skb_nsg(skb, rxm->offset + prot->prepend_size,
1381 				 rxm->full_len - prot->prepend_size);
1382 	} else {
1383 		n_sgout = 0;
1384 		*zc = false;
1385 		n_sgin = skb_cow_data(skb, 0, &unused);
1386 	}
1387 
1388 	if (n_sgin < 1)
1389 		return -EBADMSG;
1390 
1391 	/* Increment to accommodate AAD */
1392 	n_sgin = n_sgin + 1;
1393 
1394 	nsg = n_sgin + n_sgout;
1395 
1396 	aead_size = sizeof(*aead_req) + crypto_aead_reqsize(ctx->aead_recv);
1397 	mem_size = aead_size + (nsg * sizeof(struct scatterlist));
1398 	mem_size = mem_size + prot->aad_size;
1399 	mem_size = mem_size + crypto_aead_ivsize(ctx->aead_recv);
1400 
1401 	/* Allocate a single block of memory which contains
1402 	 * aead_req || sgin[] || sgout[] || aad || iv.
1403 	 * This order achieves correct alignment for aead_req, sgin, sgout.
1404 	 */
1405 	mem = kmalloc(mem_size, sk->sk_allocation);
1406 	if (!mem)
1407 		return -ENOMEM;
1408 
1409 	/* Segment the allocated memory */
1410 	aead_req = (struct aead_request *)mem;
1411 	sgin = (struct scatterlist *)(mem + aead_size);
1412 	sgout = sgin + n_sgin;
1413 	aad = (u8 *)(sgout + n_sgout);
1414 	iv = aad + prot->aad_size;
1415 
1416 	/* For CCM based ciphers, first byte of nonce+iv is always '2' */
1417 	if (prot->cipher_type == TLS_CIPHER_AES_CCM_128) {
1418 		iv[0] = 2;
1419 		iv_offset = 1;
1420 	}
1421 
1422 	/* Prepare IV */
1423 	err = skb_copy_bits(skb, rxm->offset + TLS_HEADER_SIZE,
1424 			    iv + iv_offset + prot->salt_size,
1425 			    prot->iv_size);
1426 	if (err < 0) {
1427 		kfree(mem);
1428 		return err;
1429 	}
1430 	if (prot->version == TLS_1_3_VERSION)
1431 		memcpy(iv + iv_offset, tls_ctx->rx.iv,
1432 		       crypto_aead_ivsize(ctx->aead_recv));
1433 	else
1434 		memcpy(iv + iv_offset, tls_ctx->rx.iv, prot->salt_size);
1435 
1436 	xor_iv_with_seq(prot->version, iv, tls_ctx->rx.rec_seq);
1437 
1438 	/* Prepare AAD */
1439 	tls_make_aad(aad, rxm->full_len - prot->overhead_size +
1440 		     prot->tail_size,
1441 		     tls_ctx->rx.rec_seq, prot->rec_seq_size,
1442 		     ctx->control, prot->version);
1443 
1444 	/* Prepare sgin */
1445 	sg_init_table(sgin, n_sgin);
1446 	sg_set_buf(&sgin[0], aad, prot->aad_size);
1447 	err = skb_to_sgvec(skb, &sgin[1],
1448 			   rxm->offset + prot->prepend_size,
1449 			   rxm->full_len - prot->prepend_size);
1450 	if (err < 0) {
1451 		kfree(mem);
1452 		return err;
1453 	}
1454 
1455 	if (n_sgout) {
1456 		if (out_iov) {
1457 			sg_init_table(sgout, n_sgout);
1458 			sg_set_buf(&sgout[0], aad, prot->aad_size);
1459 
1460 			*chunk = 0;
1461 			err = tls_setup_from_iter(sk, out_iov, data_len,
1462 						  &pages, chunk, &sgout[1],
1463 						  (n_sgout - 1));
1464 			if (err < 0)
1465 				goto fallback_to_reg_recv;
1466 		} else if (out_sg) {
1467 			memcpy(sgout, out_sg, n_sgout * sizeof(*sgout));
1468 		} else {
1469 			goto fallback_to_reg_recv;
1470 		}
1471 	} else {
1472 fallback_to_reg_recv:
1473 		sgout = sgin;
1474 		pages = 0;
1475 		*chunk = data_len;
1476 		*zc = false;
1477 	}
1478 
1479 	/* Prepare and submit AEAD request */
1480 	err = tls_do_decryption(sk, skb, sgin, sgout, iv,
1481 				data_len, aead_req, async);
1482 	if (err == -EINPROGRESS)
1483 		return err;
1484 
1485 	/* Release the pages in case iov was mapped to pages */
1486 	for (; pages > 0; pages--)
1487 		put_page(sg_page(&sgout[pages]));
1488 
1489 	kfree(mem);
1490 	return err;
1491 }
1492 
1493 static int decrypt_skb_update(struct sock *sk, struct sk_buff *skb,
1494 			      struct iov_iter *dest, int *chunk, bool *zc,
1495 			      bool async)
1496 {
1497 	struct tls_context *tls_ctx = tls_get_ctx(sk);
1498 	struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
1499 	struct tls_prot_info *prot = &tls_ctx->prot_info;
1500 	struct strp_msg *rxm = strp_msg(skb);
1501 	int pad, err = 0;
1502 
1503 	if (!ctx->decrypted) {
1504 		if (tls_ctx->rx_conf == TLS_HW) {
1505 			err = tls_device_decrypted(sk, tls_ctx, skb, rxm);
1506 			if (err < 0)
1507 				return err;
1508 		}
1509 
1510 		/* Still not decrypted after tls_device */
1511 		if (!ctx->decrypted) {
1512 			err = decrypt_internal(sk, skb, dest, NULL, chunk, zc,
1513 					       async);
1514 			if (err < 0) {
1515 				if (err == -EINPROGRESS)
1516 					tls_advance_record_sn(sk, prot,
1517 							      &tls_ctx->rx);
1518 
1519 				return err;
1520 			}
1521 		} else {
1522 			*zc = false;
1523 		}
1524 
1525 		pad = padding_length(ctx, prot, skb);
1526 		if (pad < 0)
1527 			return pad;
1528 
1529 		rxm->full_len -= pad;
1530 		rxm->offset += prot->prepend_size;
1531 		rxm->full_len -= prot->overhead_size;
1532 		tls_advance_record_sn(sk, prot, &tls_ctx->rx);
1533 		ctx->decrypted = 1;
1534 		ctx->saved_data_ready(sk);
1535 	} else {
1536 		*zc = false;
1537 	}
1538 
1539 	return err;
1540 }
1541 
1542 int decrypt_skb(struct sock *sk, struct sk_buff *skb,
1543 		struct scatterlist *sgout)
1544 {
1545 	bool zc = true;
1546 	int chunk;
1547 
1548 	return decrypt_internal(sk, skb, NULL, sgout, &chunk, &zc, false);
1549 }
1550 
1551 static bool tls_sw_advance_skb(struct sock *sk, struct sk_buff *skb,
1552 			       unsigned int len)
1553 {
1554 	struct tls_context *tls_ctx = tls_get_ctx(sk);
1555 	struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
1556 
1557 	if (skb) {
1558 		struct strp_msg *rxm = strp_msg(skb);
1559 
1560 		if (len < rxm->full_len) {
1561 			rxm->offset += len;
1562 			rxm->full_len -= len;
1563 			return false;
1564 		}
1565 		consume_skb(skb);
1566 	}
1567 
1568 	/* Finished with message */
1569 	ctx->recv_pkt = NULL;
1570 	__strp_unpause(&ctx->strp);
1571 
1572 	return true;
1573 }
1574 
1575 /* This function traverses the rx_list in tls receive context to copies the
1576  * decrypted records into the buffer provided by caller zero copy is not
1577  * true. Further, the records are removed from the rx_list if it is not a peek
1578  * case and the record has been consumed completely.
1579  */
1580 static int process_rx_list(struct tls_sw_context_rx *ctx,
1581 			   struct msghdr *msg,
1582 			   u8 *control,
1583 			   bool *cmsg,
1584 			   size_t skip,
1585 			   size_t len,
1586 			   bool zc,
1587 			   bool is_peek)
1588 {
1589 	struct sk_buff *skb = skb_peek(&ctx->rx_list);
1590 	u8 ctrl = *control;
1591 	u8 msgc = *cmsg;
1592 	struct tls_msg *tlm;
1593 	ssize_t copied = 0;
1594 
1595 	/* Set the record type in 'control' if caller didn't pass it */
1596 	if (!ctrl && skb) {
1597 		tlm = tls_msg(skb);
1598 		ctrl = tlm->control;
1599 	}
1600 
1601 	while (skip && skb) {
1602 		struct strp_msg *rxm = strp_msg(skb);
1603 		tlm = tls_msg(skb);
1604 
1605 		/* Cannot process a record of different type */
1606 		if (ctrl != tlm->control)
1607 			return 0;
1608 
1609 		if (skip < rxm->full_len)
1610 			break;
1611 
1612 		skip = skip - rxm->full_len;
1613 		skb = skb_peek_next(skb, &ctx->rx_list);
1614 	}
1615 
1616 	while (len && skb) {
1617 		struct sk_buff *next_skb;
1618 		struct strp_msg *rxm = strp_msg(skb);
1619 		int chunk = min_t(unsigned int, rxm->full_len - skip, len);
1620 
1621 		tlm = tls_msg(skb);
1622 
1623 		/* Cannot process a record of different type */
1624 		if (ctrl != tlm->control)
1625 			return 0;
1626 
1627 		/* Set record type if not already done. For a non-data record,
1628 		 * do not proceed if record type could not be copied.
1629 		 */
1630 		if (!msgc) {
1631 			int cerr = put_cmsg(msg, SOL_TLS, TLS_GET_RECORD_TYPE,
1632 					    sizeof(ctrl), &ctrl);
1633 			msgc = true;
1634 			if (ctrl != TLS_RECORD_TYPE_DATA) {
1635 				if (cerr || msg->msg_flags & MSG_CTRUNC)
1636 					return -EIO;
1637 
1638 				*cmsg = msgc;
1639 			}
1640 		}
1641 
1642 		if (!zc || (rxm->full_len - skip) > len) {
1643 			int err = skb_copy_datagram_msg(skb, rxm->offset + skip,
1644 						    msg, chunk);
1645 			if (err < 0)
1646 				return err;
1647 		}
1648 
1649 		len = len - chunk;
1650 		copied = copied + chunk;
1651 
1652 		/* Consume the data from record if it is non-peek case*/
1653 		if (!is_peek) {
1654 			rxm->offset = rxm->offset + chunk;
1655 			rxm->full_len = rxm->full_len - chunk;
1656 
1657 			/* Return if there is unconsumed data in the record */
1658 			if (rxm->full_len - skip)
1659 				break;
1660 		}
1661 
1662 		/* The remaining skip-bytes must lie in 1st record in rx_list.
1663 		 * So from the 2nd record, 'skip' should be 0.
1664 		 */
1665 		skip = 0;
1666 
1667 		if (msg)
1668 			msg->msg_flags |= MSG_EOR;
1669 
1670 		next_skb = skb_peek_next(skb, &ctx->rx_list);
1671 
1672 		if (!is_peek) {
1673 			skb_unlink(skb, &ctx->rx_list);
1674 			consume_skb(skb);
1675 		}
1676 
1677 		skb = next_skb;
1678 	}
1679 
1680 	*control = ctrl;
1681 	return copied;
1682 }
1683 
1684 int tls_sw_recvmsg(struct sock *sk,
1685 		   struct msghdr *msg,
1686 		   size_t len,
1687 		   int nonblock,
1688 		   int flags,
1689 		   int *addr_len)
1690 {
1691 	struct tls_context *tls_ctx = tls_get_ctx(sk);
1692 	struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
1693 	struct tls_prot_info *prot = &tls_ctx->prot_info;
1694 	struct sk_psock *psock;
1695 	unsigned char control = 0;
1696 	ssize_t decrypted = 0;
1697 	struct strp_msg *rxm;
1698 	struct tls_msg *tlm;
1699 	struct sk_buff *skb;
1700 	ssize_t copied = 0;
1701 	bool cmsg = false;
1702 	int target, err = 0;
1703 	long timeo;
1704 	bool is_kvec = iov_iter_is_kvec(&msg->msg_iter);
1705 	bool is_peek = flags & MSG_PEEK;
1706 	int num_async = 0;
1707 
1708 	flags |= nonblock;
1709 
1710 	if (unlikely(flags & MSG_ERRQUEUE))
1711 		return sock_recv_errqueue(sk, msg, len, SOL_IP, IP_RECVERR);
1712 
1713 	psock = sk_psock_get(sk);
1714 	lock_sock(sk);
1715 
1716 	/* Process pending decrypted records. It must be non-zero-copy */
1717 	err = process_rx_list(ctx, msg, &control, &cmsg, 0, len, false,
1718 			      is_peek);
1719 	if (err < 0) {
1720 		tls_err_abort(sk, err);
1721 		goto end;
1722 	} else {
1723 		copied = err;
1724 	}
1725 
1726 	if (len <= copied)
1727 		goto recv_end;
1728 
1729 	target = sock_rcvlowat(sk, flags & MSG_WAITALL, len);
1730 	len = len - copied;
1731 	timeo = sock_rcvtimeo(sk, flags & MSG_DONTWAIT);
1732 
1733 	while (len && (decrypted + copied < target || ctx->recv_pkt)) {
1734 		bool retain_skb = false;
1735 		bool zc = false;
1736 		int to_decrypt;
1737 		int chunk = 0;
1738 		bool async_capable;
1739 		bool async = false;
1740 
1741 		skb = tls_wait_data(sk, psock, flags, timeo, &err);
1742 		if (!skb) {
1743 			if (psock) {
1744 				int ret = __tcp_bpf_recvmsg(sk, psock,
1745 							    msg, len, flags);
1746 
1747 				if (ret > 0) {
1748 					decrypted += ret;
1749 					len -= ret;
1750 					continue;
1751 				}
1752 			}
1753 			goto recv_end;
1754 		} else {
1755 			tlm = tls_msg(skb);
1756 			if (prot->version == TLS_1_3_VERSION)
1757 				tlm->control = 0;
1758 			else
1759 				tlm->control = ctx->control;
1760 		}
1761 
1762 		rxm = strp_msg(skb);
1763 
1764 		to_decrypt = rxm->full_len - prot->overhead_size;
1765 
1766 		if (to_decrypt <= len && !is_kvec && !is_peek &&
1767 		    ctx->control == TLS_RECORD_TYPE_DATA &&
1768 		    prot->version != TLS_1_3_VERSION)
1769 			zc = true;
1770 
1771 		/* Do not use async mode if record is non-data */
1772 		if (ctx->control == TLS_RECORD_TYPE_DATA)
1773 			async_capable = ctx->async_capable;
1774 		else
1775 			async_capable = false;
1776 
1777 		err = decrypt_skb_update(sk, skb, &msg->msg_iter,
1778 					 &chunk, &zc, async_capable);
1779 		if (err < 0 && err != -EINPROGRESS) {
1780 			tls_err_abort(sk, EBADMSG);
1781 			goto recv_end;
1782 		}
1783 
1784 		if (err == -EINPROGRESS) {
1785 			async = true;
1786 			num_async++;
1787 		} else if (prot->version == TLS_1_3_VERSION) {
1788 			tlm->control = ctx->control;
1789 		}
1790 
1791 		/* If the type of records being processed is not known yet,
1792 		 * set it to record type just dequeued. If it is already known,
1793 		 * but does not match the record type just dequeued, go to end.
1794 		 * We always get record type here since for tls1.2, record type
1795 		 * is known just after record is dequeued from stream parser.
1796 		 * For tls1.3, we disable async.
1797 		 */
1798 
1799 		if (!control)
1800 			control = tlm->control;
1801 		else if (control != tlm->control)
1802 			goto recv_end;
1803 
1804 		if (!cmsg) {
1805 			int cerr;
1806 
1807 			cerr = put_cmsg(msg, SOL_TLS, TLS_GET_RECORD_TYPE,
1808 					sizeof(control), &control);
1809 			cmsg = true;
1810 			if (control != TLS_RECORD_TYPE_DATA) {
1811 				if (cerr || msg->msg_flags & MSG_CTRUNC) {
1812 					err = -EIO;
1813 					goto recv_end;
1814 				}
1815 			}
1816 		}
1817 
1818 		if (async)
1819 			goto pick_next_record;
1820 
1821 		if (!zc) {
1822 			if (rxm->full_len > len) {
1823 				retain_skb = true;
1824 				chunk = len;
1825 			} else {
1826 				chunk = rxm->full_len;
1827 			}
1828 
1829 			err = skb_copy_datagram_msg(skb, rxm->offset,
1830 						    msg, chunk);
1831 			if (err < 0)
1832 				goto recv_end;
1833 
1834 			if (!is_peek) {
1835 				rxm->offset = rxm->offset + chunk;
1836 				rxm->full_len = rxm->full_len - chunk;
1837 			}
1838 		}
1839 
1840 pick_next_record:
1841 		if (chunk > len)
1842 			chunk = len;
1843 
1844 		decrypted += chunk;
1845 		len -= chunk;
1846 
1847 		/* For async or peek case, queue the current skb */
1848 		if (async || is_peek || retain_skb) {
1849 			skb_queue_tail(&ctx->rx_list, skb);
1850 			skb = NULL;
1851 		}
1852 
1853 		if (tls_sw_advance_skb(sk, skb, chunk)) {
1854 			/* Return full control message to
1855 			 * userspace before trying to parse
1856 			 * another message type
1857 			 */
1858 			msg->msg_flags |= MSG_EOR;
1859 			if (ctx->control != TLS_RECORD_TYPE_DATA)
1860 				goto recv_end;
1861 		} else {
1862 			break;
1863 		}
1864 	}
1865 
1866 recv_end:
1867 	if (num_async) {
1868 		/* Wait for all previously submitted records to be decrypted */
1869 		smp_store_mb(ctx->async_notify, true);
1870 		if (atomic_read(&ctx->decrypt_pending)) {
1871 			err = crypto_wait_req(-EINPROGRESS, &ctx->async_wait);
1872 			if (err) {
1873 				/* one of async decrypt failed */
1874 				tls_err_abort(sk, err);
1875 				copied = 0;
1876 				decrypted = 0;
1877 				goto end;
1878 			}
1879 		} else {
1880 			reinit_completion(&ctx->async_wait.completion);
1881 		}
1882 		WRITE_ONCE(ctx->async_notify, false);
1883 
1884 		/* Drain records from the rx_list & copy if required */
1885 		if (is_peek || is_kvec)
1886 			err = process_rx_list(ctx, msg, &control, &cmsg, copied,
1887 					      decrypted, false, is_peek);
1888 		else
1889 			err = process_rx_list(ctx, msg, &control, &cmsg, 0,
1890 					      decrypted, true, is_peek);
1891 		if (err < 0) {
1892 			tls_err_abort(sk, err);
1893 			copied = 0;
1894 			goto end;
1895 		}
1896 	}
1897 
1898 	copied += decrypted;
1899 
1900 end:
1901 	release_sock(sk);
1902 	if (psock)
1903 		sk_psock_put(sk, psock);
1904 	return copied ? : err;
1905 }
1906 
1907 ssize_t tls_sw_splice_read(struct socket *sock,  loff_t *ppos,
1908 			   struct pipe_inode_info *pipe,
1909 			   size_t len, unsigned int flags)
1910 {
1911 	struct tls_context *tls_ctx = tls_get_ctx(sock->sk);
1912 	struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
1913 	struct strp_msg *rxm = NULL;
1914 	struct sock *sk = sock->sk;
1915 	struct sk_buff *skb;
1916 	ssize_t copied = 0;
1917 	int err = 0;
1918 	long timeo;
1919 	int chunk;
1920 	bool zc = false;
1921 
1922 	lock_sock(sk);
1923 
1924 	timeo = sock_rcvtimeo(sk, flags & MSG_DONTWAIT);
1925 
1926 	skb = tls_wait_data(sk, NULL, flags, timeo, &err);
1927 	if (!skb)
1928 		goto splice_read_end;
1929 
1930 	if (!ctx->decrypted) {
1931 		err = decrypt_skb_update(sk, skb, NULL, &chunk, &zc, false);
1932 
1933 		/* splice does not support reading control messages */
1934 		if (ctx->control != TLS_RECORD_TYPE_DATA) {
1935 			err = -EINVAL;
1936 			goto splice_read_end;
1937 		}
1938 
1939 		if (err < 0) {
1940 			tls_err_abort(sk, EBADMSG);
1941 			goto splice_read_end;
1942 		}
1943 		ctx->decrypted = 1;
1944 	}
1945 	rxm = strp_msg(skb);
1946 
1947 	chunk = min_t(unsigned int, rxm->full_len, len);
1948 	copied = skb_splice_bits(skb, sk, rxm->offset, pipe, chunk, flags);
1949 	if (copied < 0)
1950 		goto splice_read_end;
1951 
1952 	if (likely(!(flags & MSG_PEEK)))
1953 		tls_sw_advance_skb(sk, skb, copied);
1954 
1955 splice_read_end:
1956 	release_sock(sk);
1957 	return copied ? : err;
1958 }
1959 
1960 bool tls_sw_stream_read(const struct sock *sk)
1961 {
1962 	struct tls_context *tls_ctx = tls_get_ctx(sk);
1963 	struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
1964 	bool ingress_empty = true;
1965 	struct sk_psock *psock;
1966 
1967 	rcu_read_lock();
1968 	psock = sk_psock(sk);
1969 	if (psock)
1970 		ingress_empty = list_empty(&psock->ingress_msg);
1971 	rcu_read_unlock();
1972 
1973 	return !ingress_empty || ctx->recv_pkt ||
1974 		!skb_queue_empty(&ctx->rx_list);
1975 }
1976 
1977 static int tls_read_size(struct strparser *strp, struct sk_buff *skb)
1978 {
1979 	struct tls_context *tls_ctx = tls_get_ctx(strp->sk);
1980 	struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
1981 	struct tls_prot_info *prot = &tls_ctx->prot_info;
1982 	char header[TLS_HEADER_SIZE + MAX_IV_SIZE];
1983 	struct strp_msg *rxm = strp_msg(skb);
1984 	size_t cipher_overhead;
1985 	size_t data_len = 0;
1986 	int ret;
1987 
1988 	/* Verify that we have a full TLS header, or wait for more data */
1989 	if (rxm->offset + prot->prepend_size > skb->len)
1990 		return 0;
1991 
1992 	/* Sanity-check size of on-stack buffer. */
1993 	if (WARN_ON(prot->prepend_size > sizeof(header))) {
1994 		ret = -EINVAL;
1995 		goto read_failure;
1996 	}
1997 
1998 	/* Linearize header to local buffer */
1999 	ret = skb_copy_bits(skb, rxm->offset, header, prot->prepend_size);
2000 
2001 	if (ret < 0)
2002 		goto read_failure;
2003 
2004 	ctx->control = header[0];
2005 
2006 	data_len = ((header[4] & 0xFF) | (header[3] << 8));
2007 
2008 	cipher_overhead = prot->tag_size;
2009 	if (prot->version != TLS_1_3_VERSION)
2010 		cipher_overhead += prot->iv_size;
2011 
2012 	if (data_len > TLS_MAX_PAYLOAD_SIZE + cipher_overhead +
2013 	    prot->tail_size) {
2014 		ret = -EMSGSIZE;
2015 		goto read_failure;
2016 	}
2017 	if (data_len < cipher_overhead) {
2018 		ret = -EBADMSG;
2019 		goto read_failure;
2020 	}
2021 
2022 	/* Note that both TLS1.3 and TLS1.2 use TLS_1_2 version here */
2023 	if (header[1] != TLS_1_2_VERSION_MINOR ||
2024 	    header[2] != TLS_1_2_VERSION_MAJOR) {
2025 		ret = -EINVAL;
2026 		goto read_failure;
2027 	}
2028 
2029 	tls_device_rx_resync_new_rec(strp->sk, data_len + TLS_HEADER_SIZE,
2030 				     TCP_SKB_CB(skb)->seq + rxm->offset);
2031 	return data_len + TLS_HEADER_SIZE;
2032 
2033 read_failure:
2034 	tls_err_abort(strp->sk, ret);
2035 
2036 	return ret;
2037 }
2038 
2039 static void tls_queue(struct strparser *strp, struct sk_buff *skb)
2040 {
2041 	struct tls_context *tls_ctx = tls_get_ctx(strp->sk);
2042 	struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
2043 
2044 	ctx->decrypted = 0;
2045 
2046 	ctx->recv_pkt = skb;
2047 	strp_pause(strp);
2048 
2049 	ctx->saved_data_ready(strp->sk);
2050 }
2051 
2052 static void tls_data_ready(struct sock *sk)
2053 {
2054 	struct tls_context *tls_ctx = tls_get_ctx(sk);
2055 	struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
2056 	struct sk_psock *psock;
2057 
2058 	strp_data_ready(&ctx->strp);
2059 
2060 	psock = sk_psock_get(sk);
2061 	if (psock && !list_empty(&psock->ingress_msg)) {
2062 		ctx->saved_data_ready(sk);
2063 		sk_psock_put(sk, psock);
2064 	}
2065 }
2066 
2067 void tls_sw_cancel_work_tx(struct tls_context *tls_ctx)
2068 {
2069 	struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
2070 
2071 	set_bit(BIT_TX_CLOSING, &ctx->tx_bitmask);
2072 	set_bit(BIT_TX_SCHEDULED, &ctx->tx_bitmask);
2073 	cancel_delayed_work_sync(&ctx->tx_work.work);
2074 }
2075 
2076 void tls_sw_release_resources_tx(struct sock *sk)
2077 {
2078 	struct tls_context *tls_ctx = tls_get_ctx(sk);
2079 	struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
2080 	struct tls_rec *rec, *tmp;
2081 
2082 	/* Wait for any pending async encryptions to complete */
2083 	smp_store_mb(ctx->async_notify, true);
2084 	if (atomic_read(&ctx->encrypt_pending))
2085 		crypto_wait_req(-EINPROGRESS, &ctx->async_wait);
2086 
2087 	tls_tx_records(sk, -1);
2088 
2089 	/* Free up un-sent records in tx_list. First, free
2090 	 * the partially sent record if any at head of tx_list.
2091 	 */
2092 	if (tls_ctx->partially_sent_record) {
2093 		tls_free_partial_record(sk, tls_ctx);
2094 		rec = list_first_entry(&ctx->tx_list,
2095 				       struct tls_rec, list);
2096 		list_del(&rec->list);
2097 		sk_msg_free(sk, &rec->msg_plaintext);
2098 		kfree(rec);
2099 	}
2100 
2101 	list_for_each_entry_safe(rec, tmp, &ctx->tx_list, list) {
2102 		list_del(&rec->list);
2103 		sk_msg_free(sk, &rec->msg_encrypted);
2104 		sk_msg_free(sk, &rec->msg_plaintext);
2105 		kfree(rec);
2106 	}
2107 
2108 	crypto_free_aead(ctx->aead_send);
2109 	tls_free_open_rec(sk);
2110 }
2111 
2112 void tls_sw_free_ctx_tx(struct tls_context *tls_ctx)
2113 {
2114 	struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
2115 
2116 	kfree(ctx);
2117 }
2118 
2119 void tls_sw_release_resources_rx(struct sock *sk)
2120 {
2121 	struct tls_context *tls_ctx = tls_get_ctx(sk);
2122 	struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
2123 
2124 	kfree(tls_ctx->rx.rec_seq);
2125 	kfree(tls_ctx->rx.iv);
2126 
2127 	if (ctx->aead_recv) {
2128 		kfree_skb(ctx->recv_pkt);
2129 		ctx->recv_pkt = NULL;
2130 		skb_queue_purge(&ctx->rx_list);
2131 		crypto_free_aead(ctx->aead_recv);
2132 		strp_stop(&ctx->strp);
2133 		/* If tls_sw_strparser_arm() was not called (cleanup paths)
2134 		 * we still want to strp_stop(), but sk->sk_data_ready was
2135 		 * never swapped.
2136 		 */
2137 		if (ctx->saved_data_ready) {
2138 			write_lock_bh(&sk->sk_callback_lock);
2139 			sk->sk_data_ready = ctx->saved_data_ready;
2140 			write_unlock_bh(&sk->sk_callback_lock);
2141 		}
2142 	}
2143 }
2144 
2145 void tls_sw_strparser_done(struct tls_context *tls_ctx)
2146 {
2147 	struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
2148 
2149 	strp_done(&ctx->strp);
2150 }
2151 
2152 void tls_sw_free_ctx_rx(struct tls_context *tls_ctx)
2153 {
2154 	struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
2155 
2156 	kfree(ctx);
2157 }
2158 
2159 void tls_sw_free_resources_rx(struct sock *sk)
2160 {
2161 	struct tls_context *tls_ctx = tls_get_ctx(sk);
2162 
2163 	tls_sw_release_resources_rx(sk);
2164 	tls_sw_free_ctx_rx(tls_ctx);
2165 }
2166 
2167 /* The work handler to transmitt the encrypted records in tx_list */
2168 static void tx_work_handler(struct work_struct *work)
2169 {
2170 	struct delayed_work *delayed_work = to_delayed_work(work);
2171 	struct tx_work *tx_work = container_of(delayed_work,
2172 					       struct tx_work, work);
2173 	struct sock *sk = tx_work->sk;
2174 	struct tls_context *tls_ctx = tls_get_ctx(sk);
2175 	struct tls_sw_context_tx *ctx;
2176 
2177 	if (unlikely(!tls_ctx))
2178 		return;
2179 
2180 	ctx = tls_sw_ctx_tx(tls_ctx);
2181 	if (test_bit(BIT_TX_CLOSING, &ctx->tx_bitmask))
2182 		return;
2183 
2184 	if (!test_and_clear_bit(BIT_TX_SCHEDULED, &ctx->tx_bitmask))
2185 		return;
2186 	mutex_lock(&tls_ctx->tx_lock);
2187 	lock_sock(sk);
2188 	tls_tx_records(sk, -1);
2189 	release_sock(sk);
2190 	mutex_unlock(&tls_ctx->tx_lock);
2191 }
2192 
2193 void tls_sw_write_space(struct sock *sk, struct tls_context *ctx)
2194 {
2195 	struct tls_sw_context_tx *tx_ctx = tls_sw_ctx_tx(ctx);
2196 
2197 	/* Schedule the transmission if tx list is ready */
2198 	if (is_tx_ready(tx_ctx) &&
2199 	    !test_and_set_bit(BIT_TX_SCHEDULED, &tx_ctx->tx_bitmask))
2200 		schedule_delayed_work(&tx_ctx->tx_work.work, 0);
2201 }
2202 
2203 void tls_sw_strparser_arm(struct sock *sk, struct tls_context *tls_ctx)
2204 {
2205 	struct tls_sw_context_rx *rx_ctx = tls_sw_ctx_rx(tls_ctx);
2206 
2207 	write_lock_bh(&sk->sk_callback_lock);
2208 	rx_ctx->saved_data_ready = sk->sk_data_ready;
2209 	sk->sk_data_ready = tls_data_ready;
2210 	write_unlock_bh(&sk->sk_callback_lock);
2211 
2212 	strp_check_rcv(&rx_ctx->strp);
2213 }
2214 
2215 int tls_set_sw_offload(struct sock *sk, struct tls_context *ctx, int tx)
2216 {
2217 	struct tls_context *tls_ctx = tls_get_ctx(sk);
2218 	struct tls_prot_info *prot = &tls_ctx->prot_info;
2219 	struct tls_crypto_info *crypto_info;
2220 	struct tls12_crypto_info_aes_gcm_128 *gcm_128_info;
2221 	struct tls12_crypto_info_aes_gcm_256 *gcm_256_info;
2222 	struct tls12_crypto_info_aes_ccm_128 *ccm_128_info;
2223 	struct tls_sw_context_tx *sw_ctx_tx = NULL;
2224 	struct tls_sw_context_rx *sw_ctx_rx = NULL;
2225 	struct cipher_context *cctx;
2226 	struct crypto_aead **aead;
2227 	struct strp_callbacks cb;
2228 	u16 nonce_size, tag_size, iv_size, rec_seq_size, salt_size;
2229 	struct crypto_tfm *tfm;
2230 	char *iv, *rec_seq, *key, *salt, *cipher_name;
2231 	size_t keysize;
2232 	int rc = 0;
2233 
2234 	if (!ctx) {
2235 		rc = -EINVAL;
2236 		goto out;
2237 	}
2238 
2239 	if (tx) {
2240 		if (!ctx->priv_ctx_tx) {
2241 			sw_ctx_tx = kzalloc(sizeof(*sw_ctx_tx), GFP_KERNEL);
2242 			if (!sw_ctx_tx) {
2243 				rc = -ENOMEM;
2244 				goto out;
2245 			}
2246 			ctx->priv_ctx_tx = sw_ctx_tx;
2247 		} else {
2248 			sw_ctx_tx =
2249 				(struct tls_sw_context_tx *)ctx->priv_ctx_tx;
2250 		}
2251 	} else {
2252 		if (!ctx->priv_ctx_rx) {
2253 			sw_ctx_rx = kzalloc(sizeof(*sw_ctx_rx), GFP_KERNEL);
2254 			if (!sw_ctx_rx) {
2255 				rc = -ENOMEM;
2256 				goto out;
2257 			}
2258 			ctx->priv_ctx_rx = sw_ctx_rx;
2259 		} else {
2260 			sw_ctx_rx =
2261 				(struct tls_sw_context_rx *)ctx->priv_ctx_rx;
2262 		}
2263 	}
2264 
2265 	if (tx) {
2266 		crypto_init_wait(&sw_ctx_tx->async_wait);
2267 		crypto_info = &ctx->crypto_send.info;
2268 		cctx = &ctx->tx;
2269 		aead = &sw_ctx_tx->aead_send;
2270 		INIT_LIST_HEAD(&sw_ctx_tx->tx_list);
2271 		INIT_DELAYED_WORK(&sw_ctx_tx->tx_work.work, tx_work_handler);
2272 		sw_ctx_tx->tx_work.sk = sk;
2273 	} else {
2274 		crypto_init_wait(&sw_ctx_rx->async_wait);
2275 		crypto_info = &ctx->crypto_recv.info;
2276 		cctx = &ctx->rx;
2277 		skb_queue_head_init(&sw_ctx_rx->rx_list);
2278 		aead = &sw_ctx_rx->aead_recv;
2279 	}
2280 
2281 	switch (crypto_info->cipher_type) {
2282 	case TLS_CIPHER_AES_GCM_128: {
2283 		nonce_size = TLS_CIPHER_AES_GCM_128_IV_SIZE;
2284 		tag_size = TLS_CIPHER_AES_GCM_128_TAG_SIZE;
2285 		iv_size = TLS_CIPHER_AES_GCM_128_IV_SIZE;
2286 		iv = ((struct tls12_crypto_info_aes_gcm_128 *)crypto_info)->iv;
2287 		rec_seq_size = TLS_CIPHER_AES_GCM_128_REC_SEQ_SIZE;
2288 		rec_seq =
2289 		 ((struct tls12_crypto_info_aes_gcm_128 *)crypto_info)->rec_seq;
2290 		gcm_128_info =
2291 			(struct tls12_crypto_info_aes_gcm_128 *)crypto_info;
2292 		keysize = TLS_CIPHER_AES_GCM_128_KEY_SIZE;
2293 		key = gcm_128_info->key;
2294 		salt = gcm_128_info->salt;
2295 		salt_size = TLS_CIPHER_AES_GCM_128_SALT_SIZE;
2296 		cipher_name = "gcm(aes)";
2297 		break;
2298 	}
2299 	case TLS_CIPHER_AES_GCM_256: {
2300 		nonce_size = TLS_CIPHER_AES_GCM_256_IV_SIZE;
2301 		tag_size = TLS_CIPHER_AES_GCM_256_TAG_SIZE;
2302 		iv_size = TLS_CIPHER_AES_GCM_256_IV_SIZE;
2303 		iv = ((struct tls12_crypto_info_aes_gcm_256 *)crypto_info)->iv;
2304 		rec_seq_size = TLS_CIPHER_AES_GCM_256_REC_SEQ_SIZE;
2305 		rec_seq =
2306 		 ((struct tls12_crypto_info_aes_gcm_256 *)crypto_info)->rec_seq;
2307 		gcm_256_info =
2308 			(struct tls12_crypto_info_aes_gcm_256 *)crypto_info;
2309 		keysize = TLS_CIPHER_AES_GCM_256_KEY_SIZE;
2310 		key = gcm_256_info->key;
2311 		salt = gcm_256_info->salt;
2312 		salt_size = TLS_CIPHER_AES_GCM_256_SALT_SIZE;
2313 		cipher_name = "gcm(aes)";
2314 		break;
2315 	}
2316 	case TLS_CIPHER_AES_CCM_128: {
2317 		nonce_size = TLS_CIPHER_AES_CCM_128_IV_SIZE;
2318 		tag_size = TLS_CIPHER_AES_CCM_128_TAG_SIZE;
2319 		iv_size = TLS_CIPHER_AES_CCM_128_IV_SIZE;
2320 		iv = ((struct tls12_crypto_info_aes_ccm_128 *)crypto_info)->iv;
2321 		rec_seq_size = TLS_CIPHER_AES_CCM_128_REC_SEQ_SIZE;
2322 		rec_seq =
2323 		((struct tls12_crypto_info_aes_ccm_128 *)crypto_info)->rec_seq;
2324 		ccm_128_info =
2325 		(struct tls12_crypto_info_aes_ccm_128 *)crypto_info;
2326 		keysize = TLS_CIPHER_AES_CCM_128_KEY_SIZE;
2327 		key = ccm_128_info->key;
2328 		salt = ccm_128_info->salt;
2329 		salt_size = TLS_CIPHER_AES_CCM_128_SALT_SIZE;
2330 		cipher_name = "ccm(aes)";
2331 		break;
2332 	}
2333 	default:
2334 		rc = -EINVAL;
2335 		goto free_priv;
2336 	}
2337 
2338 	/* Sanity-check the sizes for stack allocations. */
2339 	if (iv_size > MAX_IV_SIZE || nonce_size > MAX_IV_SIZE ||
2340 	    rec_seq_size > TLS_MAX_REC_SEQ_SIZE) {
2341 		rc = -EINVAL;
2342 		goto free_priv;
2343 	}
2344 
2345 	if (crypto_info->version == TLS_1_3_VERSION) {
2346 		nonce_size = 0;
2347 		prot->aad_size = TLS_HEADER_SIZE;
2348 		prot->tail_size = 1;
2349 	} else {
2350 		prot->aad_size = TLS_AAD_SPACE_SIZE;
2351 		prot->tail_size = 0;
2352 	}
2353 
2354 	prot->version = crypto_info->version;
2355 	prot->cipher_type = crypto_info->cipher_type;
2356 	prot->prepend_size = TLS_HEADER_SIZE + nonce_size;
2357 	prot->tag_size = tag_size;
2358 	prot->overhead_size = prot->prepend_size +
2359 			      prot->tag_size + prot->tail_size;
2360 	prot->iv_size = iv_size;
2361 	prot->salt_size = salt_size;
2362 	cctx->iv = kmalloc(iv_size + salt_size, GFP_KERNEL);
2363 	if (!cctx->iv) {
2364 		rc = -ENOMEM;
2365 		goto free_priv;
2366 	}
2367 	/* Note: 128 & 256 bit salt are the same size */
2368 	prot->rec_seq_size = rec_seq_size;
2369 	memcpy(cctx->iv, salt, salt_size);
2370 	memcpy(cctx->iv + salt_size, iv, iv_size);
2371 	cctx->rec_seq = kmemdup(rec_seq, rec_seq_size, GFP_KERNEL);
2372 	if (!cctx->rec_seq) {
2373 		rc = -ENOMEM;
2374 		goto free_iv;
2375 	}
2376 
2377 	if (!*aead) {
2378 		*aead = crypto_alloc_aead(cipher_name, 0, 0);
2379 		if (IS_ERR(*aead)) {
2380 			rc = PTR_ERR(*aead);
2381 			*aead = NULL;
2382 			goto free_rec_seq;
2383 		}
2384 	}
2385 
2386 	ctx->push_pending_record = tls_sw_push_pending_record;
2387 
2388 	rc = crypto_aead_setkey(*aead, key, keysize);
2389 
2390 	if (rc)
2391 		goto free_aead;
2392 
2393 	rc = crypto_aead_setauthsize(*aead, prot->tag_size);
2394 	if (rc)
2395 		goto free_aead;
2396 
2397 	if (sw_ctx_rx) {
2398 		tfm = crypto_aead_tfm(sw_ctx_rx->aead_recv);
2399 
2400 		if (crypto_info->version == TLS_1_3_VERSION)
2401 			sw_ctx_rx->async_capable = 0;
2402 		else
2403 			sw_ctx_rx->async_capable =
2404 				!!(tfm->__crt_alg->cra_flags &
2405 				   CRYPTO_ALG_ASYNC);
2406 
2407 		/* Set up strparser */
2408 		memset(&cb, 0, sizeof(cb));
2409 		cb.rcv_msg = tls_queue;
2410 		cb.parse_msg = tls_read_size;
2411 
2412 		strp_init(&sw_ctx_rx->strp, sk, &cb);
2413 	}
2414 
2415 	goto out;
2416 
2417 free_aead:
2418 	crypto_free_aead(*aead);
2419 	*aead = NULL;
2420 free_rec_seq:
2421 	kfree(cctx->rec_seq);
2422 	cctx->rec_seq = NULL;
2423 free_iv:
2424 	kfree(cctx->iv);
2425 	cctx->iv = NULL;
2426 free_priv:
2427 	if (tx) {
2428 		kfree(ctx->priv_ctx_tx);
2429 		ctx->priv_ctx_tx = NULL;
2430 	} else {
2431 		kfree(ctx->priv_ctx_rx);
2432 		ctx->priv_ctx_rx = NULL;
2433 	}
2434 out:
2435 	return rc;
2436 }
2437