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/splice.h>
42 #include <crypto/aead.h>
43 
44 #include <net/strparser.h>
45 #include <net/tls.h>
46 
47 #include "tls.h"
48 
49 struct tls_decrypt_arg {
50 	struct_group(inargs,
51 	bool zc;
52 	bool async;
53 	u8 tail;
54 	);
55 
56 	struct sk_buff *skb;
57 };
58 
59 struct tls_decrypt_ctx {
60 	u8 iv[MAX_IV_SIZE];
61 	u8 aad[TLS_MAX_AAD_SIZE];
62 	u8 tail;
63 	struct scatterlist sg[];
64 };
65 
tls_err_abort(struct sock * sk,int err)66 noinline void tls_err_abort(struct sock *sk, int err)
67 {
68 	WARN_ON_ONCE(err >= 0);
69 	/* sk->sk_err should contain a positive error code. */
70 	sk->sk_err = -err;
71 	sk_error_report(sk);
72 }
73 
__skb_nsg(struct sk_buff * skb,int offset,int len,unsigned int recursion_level)74 static int __skb_nsg(struct sk_buff *skb, int offset, int len,
75                      unsigned int recursion_level)
76 {
77         int start = skb_headlen(skb);
78         int i, chunk = start - offset;
79         struct sk_buff *frag_iter;
80         int elt = 0;
81 
82         if (unlikely(recursion_level >= 24))
83                 return -EMSGSIZE;
84 
85         if (chunk > 0) {
86                 if (chunk > len)
87                         chunk = len;
88                 elt++;
89                 len -= chunk;
90                 if (len == 0)
91                         return elt;
92                 offset += chunk;
93         }
94 
95         for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
96                 int end;
97 
98                 WARN_ON(start > offset + len);
99 
100                 end = start + skb_frag_size(&skb_shinfo(skb)->frags[i]);
101                 chunk = end - offset;
102                 if (chunk > 0) {
103                         if (chunk > len)
104                                 chunk = len;
105                         elt++;
106                         len -= chunk;
107                         if (len == 0)
108                                 return elt;
109                         offset += chunk;
110                 }
111                 start = end;
112         }
113 
114         if (unlikely(skb_has_frag_list(skb))) {
115                 skb_walk_frags(skb, frag_iter) {
116                         int end, ret;
117 
118                         WARN_ON(start > offset + len);
119 
120                         end = start + frag_iter->len;
121                         chunk = end - offset;
122                         if (chunk > 0) {
123                                 if (chunk > len)
124                                         chunk = len;
125                                 ret = __skb_nsg(frag_iter, offset - start, chunk,
126                                                 recursion_level + 1);
127                                 if (unlikely(ret < 0))
128                                         return ret;
129                                 elt += ret;
130                                 len -= chunk;
131                                 if (len == 0)
132                                         return elt;
133                                 offset += chunk;
134                         }
135                         start = end;
136                 }
137         }
138         BUG_ON(len);
139         return elt;
140 }
141 
142 /* Return the number of scatterlist elements required to completely map the
143  * skb, or -EMSGSIZE if the recursion depth is exceeded.
144  */
skb_nsg(struct sk_buff * skb,int offset,int len)145 static int skb_nsg(struct sk_buff *skb, int offset, int len)
146 {
147         return __skb_nsg(skb, offset, len, 0);
148 }
149 
tls_padding_length(struct tls_prot_info * prot,struct sk_buff * skb,struct tls_decrypt_arg * darg)150 static int tls_padding_length(struct tls_prot_info *prot, struct sk_buff *skb,
151 			      struct tls_decrypt_arg *darg)
152 {
153 	struct strp_msg *rxm = strp_msg(skb);
154 	struct tls_msg *tlm = tls_msg(skb);
155 	int sub = 0;
156 
157 	/* Determine zero-padding length */
158 	if (prot->version == TLS_1_3_VERSION) {
159 		int offset = rxm->full_len - TLS_TAG_SIZE - 1;
160 		char content_type = darg->zc ? darg->tail : 0;
161 		int err;
162 
163 		while (content_type == 0) {
164 			if (offset < prot->prepend_size)
165 				return -EBADMSG;
166 			err = skb_copy_bits(skb, rxm->offset + offset,
167 					    &content_type, 1);
168 			if (err)
169 				return err;
170 			if (content_type)
171 				break;
172 			sub++;
173 			offset--;
174 		}
175 		tlm->control = content_type;
176 	}
177 	return sub;
178 }
179 
tls_decrypt_done(struct crypto_async_request * req,int err)180 static void tls_decrypt_done(struct crypto_async_request *req, int err)
181 {
182 	struct aead_request *aead_req = (struct aead_request *)req;
183 	struct scatterlist *sgout = aead_req->dst;
184 	struct scatterlist *sgin = aead_req->src;
185 	struct tls_sw_context_rx *ctx;
186 	struct tls_context *tls_ctx;
187 	struct scatterlist *sg;
188 	unsigned int pages;
189 	struct sock *sk;
190 
191 	sk = (struct sock *)req->data;
192 	tls_ctx = tls_get_ctx(sk);
193 	ctx = tls_sw_ctx_rx(tls_ctx);
194 
195 	/* Propagate if there was an err */
196 	if (err) {
197 		if (err == -EBADMSG)
198 			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSDECRYPTERROR);
199 		ctx->async_wait.err = err;
200 		tls_err_abort(sk, err);
201 	}
202 
203 	/* Free the destination pages if skb was not decrypted inplace */
204 	if (sgout != sgin) {
205 		/* Skip the first S/G entry as it points to AAD */
206 		for_each_sg(sg_next(sgout), sg, UINT_MAX, pages) {
207 			if (!sg)
208 				break;
209 			put_page(sg_page(sg));
210 		}
211 	}
212 
213 	kfree(aead_req);
214 
215 	spin_lock_bh(&ctx->decrypt_compl_lock);
216 	if (!atomic_dec_return(&ctx->decrypt_pending))
217 		complete(&ctx->async_wait.completion);
218 	spin_unlock_bh(&ctx->decrypt_compl_lock);
219 }
220 
tls_do_decryption(struct sock * sk,struct scatterlist * sgin,struct scatterlist * sgout,char * iv_recv,size_t data_len,struct aead_request * aead_req,struct tls_decrypt_arg * darg)221 static int tls_do_decryption(struct sock *sk,
222 			     struct scatterlist *sgin,
223 			     struct scatterlist *sgout,
224 			     char *iv_recv,
225 			     size_t data_len,
226 			     struct aead_request *aead_req,
227 			     struct tls_decrypt_arg *darg)
228 {
229 	struct tls_context *tls_ctx = tls_get_ctx(sk);
230 	struct tls_prot_info *prot = &tls_ctx->prot_info;
231 	struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
232 	int ret;
233 
234 	aead_request_set_tfm(aead_req, ctx->aead_recv);
235 	aead_request_set_ad(aead_req, prot->aad_size);
236 	aead_request_set_crypt(aead_req, sgin, sgout,
237 			       data_len + prot->tag_size,
238 			       (u8 *)iv_recv);
239 
240 	if (darg->async) {
241 		aead_request_set_callback(aead_req,
242 					  CRYPTO_TFM_REQ_MAY_BACKLOG,
243 					  tls_decrypt_done, sk);
244 		atomic_inc(&ctx->decrypt_pending);
245 	} else {
246 		aead_request_set_callback(aead_req,
247 					  CRYPTO_TFM_REQ_MAY_BACKLOG,
248 					  crypto_req_done, &ctx->async_wait);
249 	}
250 
251 	ret = crypto_aead_decrypt(aead_req);
252 	if (ret == -EINPROGRESS) {
253 		if (darg->async)
254 			return 0;
255 
256 		ret = crypto_wait_req(ret, &ctx->async_wait);
257 	}
258 	darg->async = false;
259 
260 	return ret;
261 }
262 
tls_trim_both_msgs(struct sock * sk,int target_size)263 static void tls_trim_both_msgs(struct sock *sk, int target_size)
264 {
265 	struct tls_context *tls_ctx = tls_get_ctx(sk);
266 	struct tls_prot_info *prot = &tls_ctx->prot_info;
267 	struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
268 	struct tls_rec *rec = ctx->open_rec;
269 
270 	sk_msg_trim(sk, &rec->msg_plaintext, target_size);
271 	if (target_size > 0)
272 		target_size += prot->overhead_size;
273 	sk_msg_trim(sk, &rec->msg_encrypted, target_size);
274 }
275 
tls_alloc_encrypted_msg(struct sock * sk,int len)276 static int tls_alloc_encrypted_msg(struct sock *sk, int len)
277 {
278 	struct tls_context *tls_ctx = tls_get_ctx(sk);
279 	struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
280 	struct tls_rec *rec = ctx->open_rec;
281 	struct sk_msg *msg_en = &rec->msg_encrypted;
282 
283 	return sk_msg_alloc(sk, msg_en, len, 0);
284 }
285 
tls_clone_plaintext_msg(struct sock * sk,int required)286 static int tls_clone_plaintext_msg(struct sock *sk, int required)
287 {
288 	struct tls_context *tls_ctx = tls_get_ctx(sk);
289 	struct tls_prot_info *prot = &tls_ctx->prot_info;
290 	struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
291 	struct tls_rec *rec = ctx->open_rec;
292 	struct sk_msg *msg_pl = &rec->msg_plaintext;
293 	struct sk_msg *msg_en = &rec->msg_encrypted;
294 	int skip, len;
295 
296 	/* We add page references worth len bytes from encrypted sg
297 	 * at the end of plaintext sg. It is guaranteed that msg_en
298 	 * has enough required room (ensured by caller).
299 	 */
300 	len = required - msg_pl->sg.size;
301 
302 	/* Skip initial bytes in msg_en's data to be able to use
303 	 * same offset of both plain and encrypted data.
304 	 */
305 	skip = prot->prepend_size + msg_pl->sg.size;
306 
307 	return sk_msg_clone(sk, msg_pl, msg_en, skip, len);
308 }
309 
tls_get_rec(struct sock * sk)310 static struct tls_rec *tls_get_rec(struct sock *sk)
311 {
312 	struct tls_context *tls_ctx = tls_get_ctx(sk);
313 	struct tls_prot_info *prot = &tls_ctx->prot_info;
314 	struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
315 	struct sk_msg *msg_pl, *msg_en;
316 	struct tls_rec *rec;
317 	int mem_size;
318 
319 	mem_size = sizeof(struct tls_rec) + crypto_aead_reqsize(ctx->aead_send);
320 
321 	rec = kzalloc(mem_size, sk->sk_allocation);
322 	if (!rec)
323 		return NULL;
324 
325 	msg_pl = &rec->msg_plaintext;
326 	msg_en = &rec->msg_encrypted;
327 
328 	sk_msg_init(msg_pl);
329 	sk_msg_init(msg_en);
330 
331 	sg_init_table(rec->sg_aead_in, 2);
332 	sg_set_buf(&rec->sg_aead_in[0], rec->aad_space, prot->aad_size);
333 	sg_unmark_end(&rec->sg_aead_in[1]);
334 
335 	sg_init_table(rec->sg_aead_out, 2);
336 	sg_set_buf(&rec->sg_aead_out[0], rec->aad_space, prot->aad_size);
337 	sg_unmark_end(&rec->sg_aead_out[1]);
338 
339 	return rec;
340 }
341 
tls_free_rec(struct sock * sk,struct tls_rec * rec)342 static void tls_free_rec(struct sock *sk, struct tls_rec *rec)
343 {
344 	sk_msg_free(sk, &rec->msg_encrypted);
345 	sk_msg_free(sk, &rec->msg_plaintext);
346 	kfree(rec);
347 }
348 
tls_free_open_rec(struct sock * sk)349 static void tls_free_open_rec(struct sock *sk)
350 {
351 	struct tls_context *tls_ctx = tls_get_ctx(sk);
352 	struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
353 	struct tls_rec *rec = ctx->open_rec;
354 
355 	if (rec) {
356 		tls_free_rec(sk, rec);
357 		ctx->open_rec = NULL;
358 	}
359 }
360 
tls_tx_records(struct sock * sk,int flags)361 int tls_tx_records(struct sock *sk, int flags)
362 {
363 	struct tls_context *tls_ctx = tls_get_ctx(sk);
364 	struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
365 	struct tls_rec *rec, *tmp;
366 	struct sk_msg *msg_en;
367 	int tx_flags, rc = 0;
368 
369 	if (tls_is_partially_sent_record(tls_ctx)) {
370 		rec = list_first_entry(&ctx->tx_list,
371 				       struct tls_rec, list);
372 
373 		if (flags == -1)
374 			tx_flags = rec->tx_flags;
375 		else
376 			tx_flags = flags;
377 
378 		rc = tls_push_partial_record(sk, tls_ctx, tx_flags);
379 		if (rc)
380 			goto tx_err;
381 
382 		/* Full record has been transmitted.
383 		 * Remove the head of tx_list
384 		 */
385 		list_del(&rec->list);
386 		sk_msg_free(sk, &rec->msg_plaintext);
387 		kfree(rec);
388 	}
389 
390 	/* Tx all ready records */
391 	list_for_each_entry_safe(rec, tmp, &ctx->tx_list, list) {
392 		if (READ_ONCE(rec->tx_ready)) {
393 			if (flags == -1)
394 				tx_flags = rec->tx_flags;
395 			else
396 				tx_flags = flags;
397 
398 			msg_en = &rec->msg_encrypted;
399 			rc = tls_push_sg(sk, tls_ctx,
400 					 &msg_en->sg.data[msg_en->sg.curr],
401 					 0, tx_flags);
402 			if (rc)
403 				goto tx_err;
404 
405 			list_del(&rec->list);
406 			sk_msg_free(sk, &rec->msg_plaintext);
407 			kfree(rec);
408 		} else {
409 			break;
410 		}
411 	}
412 
413 tx_err:
414 	if (rc < 0 && rc != -EAGAIN)
415 		tls_err_abort(sk, -EBADMSG);
416 
417 	return rc;
418 }
419 
tls_encrypt_done(struct crypto_async_request * req,int err)420 static void tls_encrypt_done(struct crypto_async_request *req, int err)
421 {
422 	struct aead_request *aead_req = (struct aead_request *)req;
423 	struct sock *sk = req->data;
424 	struct tls_context *tls_ctx = tls_get_ctx(sk);
425 	struct tls_prot_info *prot = &tls_ctx->prot_info;
426 	struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
427 	struct scatterlist *sge;
428 	struct sk_msg *msg_en;
429 	struct tls_rec *rec;
430 	bool ready = false;
431 	int pending;
432 
433 	rec = container_of(aead_req, struct tls_rec, aead_req);
434 	msg_en = &rec->msg_encrypted;
435 
436 	sge = sk_msg_elem(msg_en, msg_en->sg.curr);
437 	sge->offset -= prot->prepend_size;
438 	sge->length += prot->prepend_size;
439 
440 	/* Check if error is previously set on socket */
441 	if (err || sk->sk_err) {
442 		rec = NULL;
443 
444 		/* If err is already set on socket, return the same code */
445 		if (sk->sk_err) {
446 			ctx->async_wait.err = -sk->sk_err;
447 		} else {
448 			ctx->async_wait.err = err;
449 			tls_err_abort(sk, err);
450 		}
451 	}
452 
453 	if (rec) {
454 		struct tls_rec *first_rec;
455 
456 		/* Mark the record as ready for transmission */
457 		smp_store_mb(rec->tx_ready, true);
458 
459 		/* If received record is at head of tx_list, schedule tx */
460 		first_rec = list_first_entry(&ctx->tx_list,
461 					     struct tls_rec, list);
462 		if (rec == first_rec)
463 			ready = true;
464 	}
465 
466 	spin_lock_bh(&ctx->encrypt_compl_lock);
467 	pending = atomic_dec_return(&ctx->encrypt_pending);
468 
469 	if (!pending && ctx->async_notify)
470 		complete(&ctx->async_wait.completion);
471 	spin_unlock_bh(&ctx->encrypt_compl_lock);
472 
473 	if (!ready)
474 		return;
475 
476 	/* Schedule the transmission */
477 	if (!test_and_set_bit(BIT_TX_SCHEDULED, &ctx->tx_bitmask))
478 		schedule_delayed_work(&ctx->tx_work.work, 1);
479 }
480 
tls_do_encryption(struct sock * sk,struct tls_context * tls_ctx,struct tls_sw_context_tx * ctx,struct aead_request * aead_req,size_t data_len,u32 start)481 static int tls_do_encryption(struct sock *sk,
482 			     struct tls_context *tls_ctx,
483 			     struct tls_sw_context_tx *ctx,
484 			     struct aead_request *aead_req,
485 			     size_t data_len, u32 start)
486 {
487 	struct tls_prot_info *prot = &tls_ctx->prot_info;
488 	struct tls_rec *rec = ctx->open_rec;
489 	struct sk_msg *msg_en = &rec->msg_encrypted;
490 	struct scatterlist *sge = sk_msg_elem(msg_en, start);
491 	int rc, iv_offset = 0;
492 
493 	/* For CCM based ciphers, first byte of IV is a constant */
494 	switch (prot->cipher_type) {
495 	case TLS_CIPHER_AES_CCM_128:
496 		rec->iv_data[0] = TLS_AES_CCM_IV_B0_BYTE;
497 		iv_offset = 1;
498 		break;
499 	case TLS_CIPHER_SM4_CCM:
500 		rec->iv_data[0] = TLS_SM4_CCM_IV_B0_BYTE;
501 		iv_offset = 1;
502 		break;
503 	}
504 
505 	memcpy(&rec->iv_data[iv_offset], tls_ctx->tx.iv,
506 	       prot->iv_size + prot->salt_size);
507 
508 	tls_xor_iv_with_seq(prot, rec->iv_data + iv_offset,
509 			    tls_ctx->tx.rec_seq);
510 
511 	sge->offset += prot->prepend_size;
512 	sge->length -= prot->prepend_size;
513 
514 	msg_en->sg.curr = start;
515 
516 	aead_request_set_tfm(aead_req, ctx->aead_send);
517 	aead_request_set_ad(aead_req, prot->aad_size);
518 	aead_request_set_crypt(aead_req, rec->sg_aead_in,
519 			       rec->sg_aead_out,
520 			       data_len, rec->iv_data);
521 
522 	aead_request_set_callback(aead_req, CRYPTO_TFM_REQ_MAY_BACKLOG,
523 				  tls_encrypt_done, sk);
524 
525 	/* Add the record in tx_list */
526 	list_add_tail((struct list_head *)&rec->list, &ctx->tx_list);
527 	atomic_inc(&ctx->encrypt_pending);
528 
529 	rc = crypto_aead_encrypt(aead_req);
530 	if (!rc || rc != -EINPROGRESS) {
531 		atomic_dec(&ctx->encrypt_pending);
532 		sge->offset -= prot->prepend_size;
533 		sge->length += prot->prepend_size;
534 	}
535 
536 	if (!rc) {
537 		WRITE_ONCE(rec->tx_ready, true);
538 	} else if (rc != -EINPROGRESS) {
539 		list_del(&rec->list);
540 		return rc;
541 	}
542 
543 	/* Unhook the record from context if encryption is not failure */
544 	ctx->open_rec = NULL;
545 	tls_advance_record_sn(sk, prot, &tls_ctx->tx);
546 	return rc;
547 }
548 
tls_split_open_record(struct sock * sk,struct tls_rec * from,struct tls_rec ** to,struct sk_msg * msg_opl,struct sk_msg * msg_oen,u32 split_point,u32 tx_overhead_size,u32 * orig_end)549 static int tls_split_open_record(struct sock *sk, struct tls_rec *from,
550 				 struct tls_rec **to, struct sk_msg *msg_opl,
551 				 struct sk_msg *msg_oen, u32 split_point,
552 				 u32 tx_overhead_size, u32 *orig_end)
553 {
554 	u32 i, j, bytes = 0, apply = msg_opl->apply_bytes;
555 	struct scatterlist *sge, *osge, *nsge;
556 	u32 orig_size = msg_opl->sg.size;
557 	struct scatterlist tmp = { };
558 	struct sk_msg *msg_npl;
559 	struct tls_rec *new;
560 	int ret;
561 
562 	new = tls_get_rec(sk);
563 	if (!new)
564 		return -ENOMEM;
565 	ret = sk_msg_alloc(sk, &new->msg_encrypted, msg_opl->sg.size +
566 			   tx_overhead_size, 0);
567 	if (ret < 0) {
568 		tls_free_rec(sk, new);
569 		return ret;
570 	}
571 
572 	*orig_end = msg_opl->sg.end;
573 	i = msg_opl->sg.start;
574 	sge = sk_msg_elem(msg_opl, i);
575 	while (apply && sge->length) {
576 		if (sge->length > apply) {
577 			u32 len = sge->length - apply;
578 
579 			get_page(sg_page(sge));
580 			sg_set_page(&tmp, sg_page(sge), len,
581 				    sge->offset + apply);
582 			sge->length = apply;
583 			bytes += apply;
584 			apply = 0;
585 		} else {
586 			apply -= sge->length;
587 			bytes += sge->length;
588 		}
589 
590 		sk_msg_iter_var_next(i);
591 		if (i == msg_opl->sg.end)
592 			break;
593 		sge = sk_msg_elem(msg_opl, i);
594 	}
595 
596 	msg_opl->sg.end = i;
597 	msg_opl->sg.curr = i;
598 	msg_opl->sg.copybreak = 0;
599 	msg_opl->apply_bytes = 0;
600 	msg_opl->sg.size = bytes;
601 
602 	msg_npl = &new->msg_plaintext;
603 	msg_npl->apply_bytes = apply;
604 	msg_npl->sg.size = orig_size - bytes;
605 
606 	j = msg_npl->sg.start;
607 	nsge = sk_msg_elem(msg_npl, j);
608 	if (tmp.length) {
609 		memcpy(nsge, &tmp, sizeof(*nsge));
610 		sk_msg_iter_var_next(j);
611 		nsge = sk_msg_elem(msg_npl, j);
612 	}
613 
614 	osge = sk_msg_elem(msg_opl, i);
615 	while (osge->length) {
616 		memcpy(nsge, osge, sizeof(*nsge));
617 		sg_unmark_end(nsge);
618 		sk_msg_iter_var_next(i);
619 		sk_msg_iter_var_next(j);
620 		if (i == *orig_end)
621 			break;
622 		osge = sk_msg_elem(msg_opl, i);
623 		nsge = sk_msg_elem(msg_npl, j);
624 	}
625 
626 	msg_npl->sg.end = j;
627 	msg_npl->sg.curr = j;
628 	msg_npl->sg.copybreak = 0;
629 
630 	*to = new;
631 	return 0;
632 }
633 
tls_merge_open_record(struct sock * sk,struct tls_rec * to,struct tls_rec * from,u32 orig_end)634 static void tls_merge_open_record(struct sock *sk, struct tls_rec *to,
635 				  struct tls_rec *from, u32 orig_end)
636 {
637 	struct sk_msg *msg_npl = &from->msg_plaintext;
638 	struct sk_msg *msg_opl = &to->msg_plaintext;
639 	struct scatterlist *osge, *nsge;
640 	u32 i, j;
641 
642 	i = msg_opl->sg.end;
643 	sk_msg_iter_var_prev(i);
644 	j = msg_npl->sg.start;
645 
646 	osge = sk_msg_elem(msg_opl, i);
647 	nsge = sk_msg_elem(msg_npl, j);
648 
649 	if (sg_page(osge) == sg_page(nsge) &&
650 	    osge->offset + osge->length == nsge->offset) {
651 		osge->length += nsge->length;
652 		put_page(sg_page(nsge));
653 	}
654 
655 	msg_opl->sg.end = orig_end;
656 	msg_opl->sg.curr = orig_end;
657 	msg_opl->sg.copybreak = 0;
658 	msg_opl->apply_bytes = msg_opl->sg.size + msg_npl->sg.size;
659 	msg_opl->sg.size += msg_npl->sg.size;
660 
661 	sk_msg_free(sk, &to->msg_encrypted);
662 	sk_msg_xfer_full(&to->msg_encrypted, &from->msg_encrypted);
663 
664 	kfree(from);
665 }
666 
tls_push_record(struct sock * sk,int flags,unsigned char record_type)667 static int tls_push_record(struct sock *sk, int flags,
668 			   unsigned char record_type)
669 {
670 	struct tls_context *tls_ctx = tls_get_ctx(sk);
671 	struct tls_prot_info *prot = &tls_ctx->prot_info;
672 	struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
673 	struct tls_rec *rec = ctx->open_rec, *tmp = NULL;
674 	u32 i, split_point, orig_end;
675 	struct sk_msg *msg_pl, *msg_en;
676 	struct aead_request *req;
677 	bool split;
678 	int rc;
679 
680 	if (!rec)
681 		return 0;
682 
683 	msg_pl = &rec->msg_plaintext;
684 	msg_en = &rec->msg_encrypted;
685 
686 	split_point = msg_pl->apply_bytes;
687 	split = split_point && split_point < msg_pl->sg.size;
688 	if (unlikely((!split &&
689 		      msg_pl->sg.size +
690 		      prot->overhead_size > msg_en->sg.size) ||
691 		     (split &&
692 		      split_point +
693 		      prot->overhead_size > msg_en->sg.size))) {
694 		split = true;
695 		split_point = msg_en->sg.size;
696 	}
697 	if (split) {
698 		rc = tls_split_open_record(sk, rec, &tmp, msg_pl, msg_en,
699 					   split_point, prot->overhead_size,
700 					   &orig_end);
701 		if (rc < 0)
702 			return rc;
703 		/* This can happen if above tls_split_open_record allocates
704 		 * a single large encryption buffer instead of two smaller
705 		 * ones. In this case adjust pointers and continue without
706 		 * split.
707 		 */
708 		if (!msg_pl->sg.size) {
709 			tls_merge_open_record(sk, rec, tmp, orig_end);
710 			msg_pl = &rec->msg_plaintext;
711 			msg_en = &rec->msg_encrypted;
712 			split = false;
713 		}
714 		sk_msg_trim(sk, msg_en, msg_pl->sg.size +
715 			    prot->overhead_size);
716 	}
717 
718 	rec->tx_flags = flags;
719 	req = &rec->aead_req;
720 
721 	i = msg_pl->sg.end;
722 	sk_msg_iter_var_prev(i);
723 
724 	rec->content_type = record_type;
725 	if (prot->version == TLS_1_3_VERSION) {
726 		/* Add content type to end of message.  No padding added */
727 		sg_set_buf(&rec->sg_content_type, &rec->content_type, 1);
728 		sg_mark_end(&rec->sg_content_type);
729 		sg_chain(msg_pl->sg.data, msg_pl->sg.end + 1,
730 			 &rec->sg_content_type);
731 	} else {
732 		sg_mark_end(sk_msg_elem(msg_pl, i));
733 	}
734 
735 	if (msg_pl->sg.end < msg_pl->sg.start) {
736 		sg_chain(&msg_pl->sg.data[msg_pl->sg.start],
737 			 MAX_SKB_FRAGS - msg_pl->sg.start + 1,
738 			 msg_pl->sg.data);
739 	}
740 
741 	i = msg_pl->sg.start;
742 	sg_chain(rec->sg_aead_in, 2, &msg_pl->sg.data[i]);
743 
744 	i = msg_en->sg.end;
745 	sk_msg_iter_var_prev(i);
746 	sg_mark_end(sk_msg_elem(msg_en, i));
747 
748 	i = msg_en->sg.start;
749 	sg_chain(rec->sg_aead_out, 2, &msg_en->sg.data[i]);
750 
751 	tls_make_aad(rec->aad_space, msg_pl->sg.size + prot->tail_size,
752 		     tls_ctx->tx.rec_seq, record_type, prot);
753 
754 	tls_fill_prepend(tls_ctx,
755 			 page_address(sg_page(&msg_en->sg.data[i])) +
756 			 msg_en->sg.data[i].offset,
757 			 msg_pl->sg.size + prot->tail_size,
758 			 record_type);
759 
760 	tls_ctx->pending_open_record_frags = false;
761 
762 	rc = tls_do_encryption(sk, tls_ctx, ctx, req,
763 			       msg_pl->sg.size + prot->tail_size, i);
764 	if (rc < 0) {
765 		if (rc != -EINPROGRESS) {
766 			tls_err_abort(sk, -EBADMSG);
767 			if (split) {
768 				tls_ctx->pending_open_record_frags = true;
769 				tls_merge_open_record(sk, rec, tmp, orig_end);
770 			}
771 		}
772 		ctx->async_capable = 1;
773 		return rc;
774 	} else if (split) {
775 		msg_pl = &tmp->msg_plaintext;
776 		msg_en = &tmp->msg_encrypted;
777 		sk_msg_trim(sk, msg_en, msg_pl->sg.size + prot->overhead_size);
778 		tls_ctx->pending_open_record_frags = true;
779 		ctx->open_rec = tmp;
780 	}
781 
782 	return tls_tx_records(sk, flags);
783 }
784 
bpf_exec_tx_verdict(struct sk_msg * msg,struct sock * sk,bool full_record,u8 record_type,ssize_t * copied,int flags)785 static int bpf_exec_tx_verdict(struct sk_msg *msg, struct sock *sk,
786 			       bool full_record, u8 record_type,
787 			       ssize_t *copied, int flags)
788 {
789 	struct tls_context *tls_ctx = tls_get_ctx(sk);
790 	struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
791 	struct sk_msg msg_redir = { };
792 	struct sk_psock *psock;
793 	struct sock *sk_redir;
794 	struct tls_rec *rec;
795 	bool enospc, policy, redir_ingress;
796 	int err = 0, send;
797 	u32 delta = 0;
798 
799 	policy = !(flags & MSG_SENDPAGE_NOPOLICY);
800 	psock = sk_psock_get(sk);
801 	if (!psock || !policy) {
802 		err = tls_push_record(sk, flags, record_type);
803 		if (err && sk->sk_err == EBADMSG) {
804 			*copied -= sk_msg_free(sk, msg);
805 			tls_free_open_rec(sk);
806 			err = -sk->sk_err;
807 		}
808 		if (psock)
809 			sk_psock_put(sk, psock);
810 		return err;
811 	}
812 more_data:
813 	enospc = sk_msg_full(msg);
814 	if (psock->eval == __SK_NONE) {
815 		delta = msg->sg.size;
816 		psock->eval = sk_psock_msg_verdict(sk, psock, msg);
817 		delta -= msg->sg.size;
818 	}
819 	if (msg->cork_bytes && msg->cork_bytes > msg->sg.size &&
820 	    !enospc && !full_record) {
821 		err = -ENOSPC;
822 		goto out_err;
823 	}
824 	msg->cork_bytes = 0;
825 	send = msg->sg.size;
826 	if (msg->apply_bytes && msg->apply_bytes < send)
827 		send = msg->apply_bytes;
828 
829 	switch (psock->eval) {
830 	case __SK_PASS:
831 		err = tls_push_record(sk, flags, record_type);
832 		if (err && sk->sk_err == EBADMSG) {
833 			*copied -= sk_msg_free(sk, msg);
834 			tls_free_open_rec(sk);
835 			err = -sk->sk_err;
836 			goto out_err;
837 		}
838 		break;
839 	case __SK_REDIRECT:
840 		redir_ingress = psock->redir_ingress;
841 		sk_redir = psock->sk_redir;
842 		memcpy(&msg_redir, msg, sizeof(*msg));
843 		if (msg->apply_bytes < send)
844 			msg->apply_bytes = 0;
845 		else
846 			msg->apply_bytes -= send;
847 		sk_msg_return_zero(sk, msg, send);
848 		msg->sg.size -= send;
849 		release_sock(sk);
850 		err = tcp_bpf_sendmsg_redir(sk_redir, redir_ingress,
851 					    &msg_redir, send, flags);
852 		lock_sock(sk);
853 		if (err < 0) {
854 			*copied -= sk_msg_free_nocharge(sk, &msg_redir);
855 			msg->sg.size = 0;
856 		}
857 		if (msg->sg.size == 0)
858 			tls_free_open_rec(sk);
859 		break;
860 	case __SK_DROP:
861 	default:
862 		sk_msg_free_partial(sk, msg, send);
863 		if (msg->apply_bytes < send)
864 			msg->apply_bytes = 0;
865 		else
866 			msg->apply_bytes -= send;
867 		if (msg->sg.size == 0)
868 			tls_free_open_rec(sk);
869 		*copied -= (send + delta);
870 		err = -EACCES;
871 	}
872 
873 	if (likely(!err)) {
874 		bool reset_eval = !ctx->open_rec;
875 
876 		rec = ctx->open_rec;
877 		if (rec) {
878 			msg = &rec->msg_plaintext;
879 			if (!msg->apply_bytes)
880 				reset_eval = true;
881 		}
882 		if (reset_eval) {
883 			psock->eval = __SK_NONE;
884 			if (psock->sk_redir) {
885 				sock_put(psock->sk_redir);
886 				psock->sk_redir = NULL;
887 			}
888 		}
889 		if (rec)
890 			goto more_data;
891 	}
892  out_err:
893 	sk_psock_put(sk, psock);
894 	return err;
895 }
896 
tls_sw_push_pending_record(struct sock * sk,int flags)897 static int tls_sw_push_pending_record(struct sock *sk, int flags)
898 {
899 	struct tls_context *tls_ctx = tls_get_ctx(sk);
900 	struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
901 	struct tls_rec *rec = ctx->open_rec;
902 	struct sk_msg *msg_pl;
903 	size_t copied;
904 
905 	if (!rec)
906 		return 0;
907 
908 	msg_pl = &rec->msg_plaintext;
909 	copied = msg_pl->sg.size;
910 	if (!copied)
911 		return 0;
912 
913 	return bpf_exec_tx_verdict(msg_pl, sk, true, TLS_RECORD_TYPE_DATA,
914 				   &copied, flags);
915 }
916 
tls_sw_sendmsg(struct sock * sk,struct msghdr * msg,size_t size)917 int tls_sw_sendmsg(struct sock *sk, struct msghdr *msg, size_t size)
918 {
919 	long timeo = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT);
920 	struct tls_context *tls_ctx = tls_get_ctx(sk);
921 	struct tls_prot_info *prot = &tls_ctx->prot_info;
922 	struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
923 	bool async_capable = ctx->async_capable;
924 	unsigned char record_type = TLS_RECORD_TYPE_DATA;
925 	bool is_kvec = iov_iter_is_kvec(&msg->msg_iter);
926 	bool eor = !(msg->msg_flags & MSG_MORE);
927 	size_t try_to_copy;
928 	ssize_t copied = 0;
929 	struct sk_msg *msg_pl, *msg_en;
930 	struct tls_rec *rec;
931 	int required_size;
932 	int num_async = 0;
933 	bool full_record;
934 	int record_room;
935 	int num_zc = 0;
936 	int orig_size;
937 	int ret = 0;
938 	int pending;
939 
940 	if (msg->msg_flags & ~(MSG_MORE | MSG_DONTWAIT | MSG_NOSIGNAL |
941 			       MSG_CMSG_COMPAT))
942 		return -EOPNOTSUPP;
943 
944 	mutex_lock(&tls_ctx->tx_lock);
945 	lock_sock(sk);
946 
947 	if (unlikely(msg->msg_controllen)) {
948 		ret = tls_process_cmsg(sk, msg, &record_type);
949 		if (ret) {
950 			if (ret == -EINPROGRESS)
951 				num_async++;
952 			else if (ret != -EAGAIN)
953 				goto send_end;
954 		}
955 	}
956 
957 	while (msg_data_left(msg)) {
958 		if (sk->sk_err) {
959 			ret = -sk->sk_err;
960 			goto send_end;
961 		}
962 
963 		if (ctx->open_rec)
964 			rec = ctx->open_rec;
965 		else
966 			rec = ctx->open_rec = tls_get_rec(sk);
967 		if (!rec) {
968 			ret = -ENOMEM;
969 			goto send_end;
970 		}
971 
972 		msg_pl = &rec->msg_plaintext;
973 		msg_en = &rec->msg_encrypted;
974 
975 		orig_size = msg_pl->sg.size;
976 		full_record = false;
977 		try_to_copy = msg_data_left(msg);
978 		record_room = TLS_MAX_PAYLOAD_SIZE - msg_pl->sg.size;
979 		if (try_to_copy >= record_room) {
980 			try_to_copy = record_room;
981 			full_record = true;
982 		}
983 
984 		required_size = msg_pl->sg.size + try_to_copy +
985 				prot->overhead_size;
986 
987 		if (!sk_stream_memory_free(sk))
988 			goto wait_for_sndbuf;
989 
990 alloc_encrypted:
991 		ret = tls_alloc_encrypted_msg(sk, required_size);
992 		if (ret) {
993 			if (ret != -ENOSPC)
994 				goto wait_for_memory;
995 
996 			/* Adjust try_to_copy according to the amount that was
997 			 * actually allocated. The difference is due
998 			 * to max sg elements limit
999 			 */
1000 			try_to_copy -= required_size - msg_en->sg.size;
1001 			full_record = true;
1002 		}
1003 
1004 		if (!is_kvec && (full_record || eor) && !async_capable) {
1005 			u32 first = msg_pl->sg.end;
1006 
1007 			ret = sk_msg_zerocopy_from_iter(sk, &msg->msg_iter,
1008 							msg_pl, try_to_copy);
1009 			if (ret)
1010 				goto fallback_to_reg_send;
1011 
1012 			num_zc++;
1013 			copied += try_to_copy;
1014 
1015 			sk_msg_sg_copy_set(msg_pl, first);
1016 			ret = bpf_exec_tx_verdict(msg_pl, sk, full_record,
1017 						  record_type, &copied,
1018 						  msg->msg_flags);
1019 			if (ret) {
1020 				if (ret == -EINPROGRESS)
1021 					num_async++;
1022 				else if (ret == -ENOMEM)
1023 					goto wait_for_memory;
1024 				else if (ctx->open_rec && ret == -ENOSPC)
1025 					goto rollback_iter;
1026 				else if (ret != -EAGAIN)
1027 					goto send_end;
1028 			}
1029 			continue;
1030 rollback_iter:
1031 			copied -= try_to_copy;
1032 			sk_msg_sg_copy_clear(msg_pl, first);
1033 			iov_iter_revert(&msg->msg_iter,
1034 					msg_pl->sg.size - orig_size);
1035 fallback_to_reg_send:
1036 			sk_msg_trim(sk, msg_pl, orig_size);
1037 		}
1038 
1039 		required_size = msg_pl->sg.size + try_to_copy;
1040 
1041 		ret = tls_clone_plaintext_msg(sk, required_size);
1042 		if (ret) {
1043 			if (ret != -ENOSPC)
1044 				goto send_end;
1045 
1046 			/* Adjust try_to_copy according to the amount that was
1047 			 * actually allocated. The difference is due
1048 			 * to max sg elements limit
1049 			 */
1050 			try_to_copy -= required_size - msg_pl->sg.size;
1051 			full_record = true;
1052 			sk_msg_trim(sk, msg_en,
1053 				    msg_pl->sg.size + prot->overhead_size);
1054 		}
1055 
1056 		if (try_to_copy) {
1057 			ret = sk_msg_memcopy_from_iter(sk, &msg->msg_iter,
1058 						       msg_pl, try_to_copy);
1059 			if (ret < 0)
1060 				goto trim_sgl;
1061 		}
1062 
1063 		/* Open records defined only if successfully copied, otherwise
1064 		 * we would trim the sg but not reset the open record frags.
1065 		 */
1066 		tls_ctx->pending_open_record_frags = true;
1067 		copied += try_to_copy;
1068 		if (full_record || eor) {
1069 			ret = bpf_exec_tx_verdict(msg_pl, sk, full_record,
1070 						  record_type, &copied,
1071 						  msg->msg_flags);
1072 			if (ret) {
1073 				if (ret == -EINPROGRESS)
1074 					num_async++;
1075 				else if (ret == -ENOMEM)
1076 					goto wait_for_memory;
1077 				else if (ret != -EAGAIN) {
1078 					if (ret == -ENOSPC)
1079 						ret = 0;
1080 					goto send_end;
1081 				}
1082 			}
1083 		}
1084 
1085 		continue;
1086 
1087 wait_for_sndbuf:
1088 		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1089 wait_for_memory:
1090 		ret = sk_stream_wait_memory(sk, &timeo);
1091 		if (ret) {
1092 trim_sgl:
1093 			if (ctx->open_rec)
1094 				tls_trim_both_msgs(sk, orig_size);
1095 			goto send_end;
1096 		}
1097 
1098 		if (ctx->open_rec && msg_en->sg.size < required_size)
1099 			goto alloc_encrypted;
1100 	}
1101 
1102 	if (!num_async) {
1103 		goto send_end;
1104 	} else if (num_zc) {
1105 		/* Wait for pending encryptions to get completed */
1106 		spin_lock_bh(&ctx->encrypt_compl_lock);
1107 		ctx->async_notify = true;
1108 
1109 		pending = atomic_read(&ctx->encrypt_pending);
1110 		spin_unlock_bh(&ctx->encrypt_compl_lock);
1111 		if (pending)
1112 			crypto_wait_req(-EINPROGRESS, &ctx->async_wait);
1113 		else
1114 			reinit_completion(&ctx->async_wait.completion);
1115 
1116 		/* There can be no concurrent accesses, since we have no
1117 		 * pending encrypt operations
1118 		 */
1119 		WRITE_ONCE(ctx->async_notify, false);
1120 
1121 		if (ctx->async_wait.err) {
1122 			ret = ctx->async_wait.err;
1123 			copied = 0;
1124 		}
1125 	}
1126 
1127 	/* Transmit if any encryptions have completed */
1128 	if (test_and_clear_bit(BIT_TX_SCHEDULED, &ctx->tx_bitmask)) {
1129 		cancel_delayed_work(&ctx->tx_work.work);
1130 		tls_tx_records(sk, msg->msg_flags);
1131 	}
1132 
1133 send_end:
1134 	ret = sk_stream_error(sk, msg->msg_flags, ret);
1135 
1136 	release_sock(sk);
1137 	mutex_unlock(&tls_ctx->tx_lock);
1138 	return copied > 0 ? copied : ret;
1139 }
1140 
tls_sw_do_sendpage(struct sock * sk,struct page * page,int offset,size_t size,int flags)1141 static int tls_sw_do_sendpage(struct sock *sk, struct page *page,
1142 			      int offset, size_t size, int flags)
1143 {
1144 	long timeo = sock_sndtimeo(sk, flags & MSG_DONTWAIT);
1145 	struct tls_context *tls_ctx = tls_get_ctx(sk);
1146 	struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
1147 	struct tls_prot_info *prot = &tls_ctx->prot_info;
1148 	unsigned char record_type = TLS_RECORD_TYPE_DATA;
1149 	struct sk_msg *msg_pl;
1150 	struct tls_rec *rec;
1151 	int num_async = 0;
1152 	ssize_t copied = 0;
1153 	bool full_record;
1154 	int record_room;
1155 	int ret = 0;
1156 	bool eor;
1157 
1158 	eor = !(flags & MSG_SENDPAGE_NOTLAST);
1159 	sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);
1160 
1161 	/* Call the sk_stream functions to manage the sndbuf mem. */
1162 	while (size > 0) {
1163 		size_t copy, required_size;
1164 
1165 		if (sk->sk_err) {
1166 			ret = -sk->sk_err;
1167 			goto sendpage_end;
1168 		}
1169 
1170 		if (ctx->open_rec)
1171 			rec = ctx->open_rec;
1172 		else
1173 			rec = ctx->open_rec = tls_get_rec(sk);
1174 		if (!rec) {
1175 			ret = -ENOMEM;
1176 			goto sendpage_end;
1177 		}
1178 
1179 		msg_pl = &rec->msg_plaintext;
1180 
1181 		full_record = false;
1182 		record_room = TLS_MAX_PAYLOAD_SIZE - msg_pl->sg.size;
1183 		copy = size;
1184 		if (copy >= record_room) {
1185 			copy = record_room;
1186 			full_record = true;
1187 		}
1188 
1189 		required_size = msg_pl->sg.size + copy + prot->overhead_size;
1190 
1191 		if (!sk_stream_memory_free(sk))
1192 			goto wait_for_sndbuf;
1193 alloc_payload:
1194 		ret = tls_alloc_encrypted_msg(sk, required_size);
1195 		if (ret) {
1196 			if (ret != -ENOSPC)
1197 				goto wait_for_memory;
1198 
1199 			/* Adjust copy according to the amount that was
1200 			 * actually allocated. The difference is due
1201 			 * to max sg elements limit
1202 			 */
1203 			copy -= required_size - msg_pl->sg.size;
1204 			full_record = true;
1205 		}
1206 
1207 		sk_msg_page_add(msg_pl, page, copy, offset);
1208 		sk_mem_charge(sk, copy);
1209 
1210 		offset += copy;
1211 		size -= copy;
1212 		copied += copy;
1213 
1214 		tls_ctx->pending_open_record_frags = true;
1215 		if (full_record || eor || sk_msg_full(msg_pl)) {
1216 			ret = bpf_exec_tx_verdict(msg_pl, sk, full_record,
1217 						  record_type, &copied, flags);
1218 			if (ret) {
1219 				if (ret == -EINPROGRESS)
1220 					num_async++;
1221 				else if (ret == -ENOMEM)
1222 					goto wait_for_memory;
1223 				else if (ret != -EAGAIN) {
1224 					if (ret == -ENOSPC)
1225 						ret = 0;
1226 					goto sendpage_end;
1227 				}
1228 			}
1229 		}
1230 		continue;
1231 wait_for_sndbuf:
1232 		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1233 wait_for_memory:
1234 		ret = sk_stream_wait_memory(sk, &timeo);
1235 		if (ret) {
1236 			if (ctx->open_rec)
1237 				tls_trim_both_msgs(sk, msg_pl->sg.size);
1238 			goto sendpage_end;
1239 		}
1240 
1241 		if (ctx->open_rec)
1242 			goto alloc_payload;
1243 	}
1244 
1245 	if (num_async) {
1246 		/* Transmit if any encryptions have completed */
1247 		if (test_and_clear_bit(BIT_TX_SCHEDULED, &ctx->tx_bitmask)) {
1248 			cancel_delayed_work(&ctx->tx_work.work);
1249 			tls_tx_records(sk, flags);
1250 		}
1251 	}
1252 sendpage_end:
1253 	ret = sk_stream_error(sk, flags, ret);
1254 	return copied > 0 ? copied : ret;
1255 }
1256 
tls_sw_sendpage_locked(struct sock * sk,struct page * page,int offset,size_t size,int flags)1257 int tls_sw_sendpage_locked(struct sock *sk, struct page *page,
1258 			   int offset, size_t size, int flags)
1259 {
1260 	if (flags & ~(MSG_MORE | MSG_DONTWAIT | MSG_NOSIGNAL |
1261 		      MSG_SENDPAGE_NOTLAST | MSG_SENDPAGE_NOPOLICY |
1262 		      MSG_NO_SHARED_FRAGS))
1263 		return -EOPNOTSUPP;
1264 
1265 	return tls_sw_do_sendpage(sk, page, offset, size, flags);
1266 }
1267 
tls_sw_sendpage(struct sock * sk,struct page * page,int offset,size_t size,int flags)1268 int tls_sw_sendpage(struct sock *sk, struct page *page,
1269 		    int offset, size_t size, int flags)
1270 {
1271 	struct tls_context *tls_ctx = tls_get_ctx(sk);
1272 	int ret;
1273 
1274 	if (flags & ~(MSG_MORE | MSG_DONTWAIT | MSG_NOSIGNAL |
1275 		      MSG_SENDPAGE_NOTLAST | MSG_SENDPAGE_NOPOLICY))
1276 		return -EOPNOTSUPP;
1277 
1278 	mutex_lock(&tls_ctx->tx_lock);
1279 	lock_sock(sk);
1280 	ret = tls_sw_do_sendpage(sk, page, offset, size, flags);
1281 	release_sock(sk);
1282 	mutex_unlock(&tls_ctx->tx_lock);
1283 	return ret;
1284 }
1285 
1286 static int
tls_rx_rec_wait(struct sock * sk,struct sk_psock * psock,bool nonblock,bool released)1287 tls_rx_rec_wait(struct sock *sk, struct sk_psock *psock, bool nonblock,
1288 		bool released)
1289 {
1290 	struct tls_context *tls_ctx = tls_get_ctx(sk);
1291 	struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
1292 	DEFINE_WAIT_FUNC(wait, woken_wake_function);
1293 	long timeo;
1294 
1295 	timeo = sock_rcvtimeo(sk, nonblock);
1296 
1297 	while (!tls_strp_msg_ready(ctx)) {
1298 		if (!sk_psock_queue_empty(psock))
1299 			return 0;
1300 
1301 		if (sk->sk_err)
1302 			return sock_error(sk);
1303 
1304 		if (!skb_queue_empty(&sk->sk_receive_queue)) {
1305 			tls_strp_check_rcv(&ctx->strp);
1306 			if (tls_strp_msg_ready(ctx))
1307 				break;
1308 		}
1309 
1310 		if (sk->sk_shutdown & RCV_SHUTDOWN)
1311 			return 0;
1312 
1313 		if (sock_flag(sk, SOCK_DONE))
1314 			return 0;
1315 
1316 		if (!timeo)
1317 			return -EAGAIN;
1318 
1319 		released = true;
1320 		add_wait_queue(sk_sleep(sk), &wait);
1321 		sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk);
1322 		sk_wait_event(sk, &timeo,
1323 			      tls_strp_msg_ready(ctx) ||
1324 			      !sk_psock_queue_empty(psock),
1325 			      &wait);
1326 		sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk);
1327 		remove_wait_queue(sk_sleep(sk), &wait);
1328 
1329 		/* Handle signals */
1330 		if (signal_pending(current))
1331 			return sock_intr_errno(timeo);
1332 	}
1333 
1334 	tls_strp_msg_load(&ctx->strp, released);
1335 
1336 	return 1;
1337 }
1338 
tls_setup_from_iter(struct iov_iter * from,int length,int * pages_used,struct scatterlist * to,int to_max_pages)1339 static int tls_setup_from_iter(struct iov_iter *from,
1340 			       int length, int *pages_used,
1341 			       struct scatterlist *to,
1342 			       int to_max_pages)
1343 {
1344 	int rc = 0, i = 0, num_elem = *pages_used, maxpages;
1345 	struct page *pages[MAX_SKB_FRAGS];
1346 	unsigned int size = 0;
1347 	ssize_t copied, use;
1348 	size_t offset;
1349 
1350 	while (length > 0) {
1351 		i = 0;
1352 		maxpages = to_max_pages - num_elem;
1353 		if (maxpages == 0) {
1354 			rc = -EFAULT;
1355 			goto out;
1356 		}
1357 		copied = iov_iter_get_pages2(from, pages,
1358 					    length,
1359 					    maxpages, &offset);
1360 		if (copied <= 0) {
1361 			rc = -EFAULT;
1362 			goto out;
1363 		}
1364 
1365 		length -= copied;
1366 		size += copied;
1367 		while (copied) {
1368 			use = min_t(int, copied, PAGE_SIZE - offset);
1369 
1370 			sg_set_page(&to[num_elem],
1371 				    pages[i], use, offset);
1372 			sg_unmark_end(&to[num_elem]);
1373 			/* We do not uncharge memory from this API */
1374 
1375 			offset = 0;
1376 			copied -= use;
1377 
1378 			i++;
1379 			num_elem++;
1380 		}
1381 	}
1382 	/* Mark the end in the last sg entry if newly added */
1383 	if (num_elem > *pages_used)
1384 		sg_mark_end(&to[num_elem - 1]);
1385 out:
1386 	if (rc)
1387 		iov_iter_revert(from, size);
1388 	*pages_used = num_elem;
1389 
1390 	return rc;
1391 }
1392 
1393 static struct sk_buff *
tls_alloc_clrtxt_skb(struct sock * sk,struct sk_buff * skb,unsigned int full_len)1394 tls_alloc_clrtxt_skb(struct sock *sk, struct sk_buff *skb,
1395 		     unsigned int full_len)
1396 {
1397 	struct strp_msg *clr_rxm;
1398 	struct sk_buff *clr_skb;
1399 	int err;
1400 
1401 	clr_skb = alloc_skb_with_frags(0, full_len, TLS_PAGE_ORDER,
1402 				       &err, sk->sk_allocation);
1403 	if (!clr_skb)
1404 		return NULL;
1405 
1406 	skb_copy_header(clr_skb, skb);
1407 	clr_skb->len = full_len;
1408 	clr_skb->data_len = full_len;
1409 
1410 	clr_rxm = strp_msg(clr_skb);
1411 	clr_rxm->offset = 0;
1412 
1413 	return clr_skb;
1414 }
1415 
1416 /* Decrypt handlers
1417  *
1418  * tls_decrypt_sw() and tls_decrypt_device() are decrypt handlers.
1419  * They must transform the darg in/out argument are as follows:
1420  *       |          Input            |         Output
1421  * -------------------------------------------------------------------
1422  *    zc | Zero-copy decrypt allowed | Zero-copy performed
1423  * async | Async decrypt allowed     | Async crypto used / in progress
1424  *   skb |            *              | Output skb
1425  *
1426  * If ZC decryption was performed darg.skb will point to the input skb.
1427  */
1428 
1429 /* This function decrypts the input skb into either out_iov or in out_sg
1430  * or in skb buffers itself. The input parameter 'darg->zc' indicates if
1431  * zero-copy mode needs to be tried or not. With zero-copy mode, either
1432  * out_iov or out_sg must be non-NULL. In case both out_iov and out_sg are
1433  * NULL, then the decryption happens inside skb buffers itself, i.e.
1434  * zero-copy gets disabled and 'darg->zc' is updated.
1435  */
tls_decrypt_sg(struct sock * sk,struct iov_iter * out_iov,struct scatterlist * out_sg,struct tls_decrypt_arg * darg)1436 static int tls_decrypt_sg(struct sock *sk, struct iov_iter *out_iov,
1437 			  struct scatterlist *out_sg,
1438 			  struct tls_decrypt_arg *darg)
1439 {
1440 	struct tls_context *tls_ctx = tls_get_ctx(sk);
1441 	struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
1442 	struct tls_prot_info *prot = &tls_ctx->prot_info;
1443 	int n_sgin, n_sgout, aead_size, err, pages = 0;
1444 	struct sk_buff *skb = tls_strp_msg(ctx);
1445 	const struct strp_msg *rxm = strp_msg(skb);
1446 	const struct tls_msg *tlm = tls_msg(skb);
1447 	struct aead_request *aead_req;
1448 	struct scatterlist *sgin = NULL;
1449 	struct scatterlist *sgout = NULL;
1450 	const int data_len = rxm->full_len - prot->overhead_size;
1451 	int tail_pages = !!prot->tail_size;
1452 	struct tls_decrypt_ctx *dctx;
1453 	struct sk_buff *clear_skb;
1454 	int iv_offset = 0;
1455 	u8 *mem;
1456 
1457 	n_sgin = skb_nsg(skb, rxm->offset + prot->prepend_size,
1458 			 rxm->full_len - prot->prepend_size);
1459 	if (n_sgin < 1)
1460 		return n_sgin ?: -EBADMSG;
1461 
1462 	if (darg->zc && (out_iov || out_sg)) {
1463 		clear_skb = NULL;
1464 
1465 		if (out_iov)
1466 			n_sgout = 1 + tail_pages +
1467 				iov_iter_npages_cap(out_iov, INT_MAX, data_len);
1468 		else
1469 			n_sgout = sg_nents(out_sg);
1470 	} else {
1471 		darg->zc = false;
1472 
1473 		clear_skb = tls_alloc_clrtxt_skb(sk, skb, rxm->full_len);
1474 		if (!clear_skb)
1475 			return -ENOMEM;
1476 
1477 		n_sgout = 1 + skb_shinfo(clear_skb)->nr_frags;
1478 	}
1479 
1480 	/* Increment to accommodate AAD */
1481 	n_sgin = n_sgin + 1;
1482 
1483 	/* Allocate a single block of memory which contains
1484 	 *   aead_req || tls_decrypt_ctx.
1485 	 * Both structs are variable length.
1486 	 */
1487 	aead_size = sizeof(*aead_req) + crypto_aead_reqsize(ctx->aead_recv);
1488 	mem = kmalloc(aead_size + struct_size(dctx, sg, n_sgin + n_sgout),
1489 		      sk->sk_allocation);
1490 	if (!mem) {
1491 		err = -ENOMEM;
1492 		goto exit_free_skb;
1493 	}
1494 
1495 	/* Segment the allocated memory */
1496 	aead_req = (struct aead_request *)mem;
1497 	dctx = (struct tls_decrypt_ctx *)(mem + aead_size);
1498 	sgin = &dctx->sg[0];
1499 	sgout = &dctx->sg[n_sgin];
1500 
1501 	/* For CCM based ciphers, first byte of nonce+iv is a constant */
1502 	switch (prot->cipher_type) {
1503 	case TLS_CIPHER_AES_CCM_128:
1504 		dctx->iv[0] = TLS_AES_CCM_IV_B0_BYTE;
1505 		iv_offset = 1;
1506 		break;
1507 	case TLS_CIPHER_SM4_CCM:
1508 		dctx->iv[0] = TLS_SM4_CCM_IV_B0_BYTE;
1509 		iv_offset = 1;
1510 		break;
1511 	}
1512 
1513 	/* Prepare IV */
1514 	if (prot->version == TLS_1_3_VERSION ||
1515 	    prot->cipher_type == TLS_CIPHER_CHACHA20_POLY1305) {
1516 		memcpy(&dctx->iv[iv_offset], tls_ctx->rx.iv,
1517 		       prot->iv_size + prot->salt_size);
1518 	} else {
1519 		err = skb_copy_bits(skb, rxm->offset + TLS_HEADER_SIZE,
1520 				    &dctx->iv[iv_offset] + prot->salt_size,
1521 				    prot->iv_size);
1522 		if (err < 0)
1523 			goto exit_free;
1524 		memcpy(&dctx->iv[iv_offset], tls_ctx->rx.iv, prot->salt_size);
1525 	}
1526 	tls_xor_iv_with_seq(prot, &dctx->iv[iv_offset], tls_ctx->rx.rec_seq);
1527 
1528 	/* Prepare AAD */
1529 	tls_make_aad(dctx->aad, rxm->full_len - prot->overhead_size +
1530 		     prot->tail_size,
1531 		     tls_ctx->rx.rec_seq, tlm->control, prot);
1532 
1533 	/* Prepare sgin */
1534 	sg_init_table(sgin, n_sgin);
1535 	sg_set_buf(&sgin[0], dctx->aad, prot->aad_size);
1536 	err = skb_to_sgvec(skb, &sgin[1],
1537 			   rxm->offset + prot->prepend_size,
1538 			   rxm->full_len - prot->prepend_size);
1539 	if (err < 0)
1540 		goto exit_free;
1541 
1542 	if (clear_skb) {
1543 		sg_init_table(sgout, n_sgout);
1544 		sg_set_buf(&sgout[0], dctx->aad, prot->aad_size);
1545 
1546 		err = skb_to_sgvec(clear_skb, &sgout[1], prot->prepend_size,
1547 				   data_len + prot->tail_size);
1548 		if (err < 0)
1549 			goto exit_free;
1550 	} else if (out_iov) {
1551 		sg_init_table(sgout, n_sgout);
1552 		sg_set_buf(&sgout[0], dctx->aad, prot->aad_size);
1553 
1554 		err = tls_setup_from_iter(out_iov, data_len, &pages, &sgout[1],
1555 					  (n_sgout - 1 - tail_pages));
1556 		if (err < 0)
1557 			goto exit_free_pages;
1558 
1559 		if (prot->tail_size) {
1560 			sg_unmark_end(&sgout[pages]);
1561 			sg_set_buf(&sgout[pages + 1], &dctx->tail,
1562 				   prot->tail_size);
1563 			sg_mark_end(&sgout[pages + 1]);
1564 		}
1565 	} else if (out_sg) {
1566 		memcpy(sgout, out_sg, n_sgout * sizeof(*sgout));
1567 	}
1568 
1569 	/* Prepare and submit AEAD request */
1570 	err = tls_do_decryption(sk, sgin, sgout, dctx->iv,
1571 				data_len + prot->tail_size, aead_req, darg);
1572 	if (err)
1573 		goto exit_free_pages;
1574 
1575 	darg->skb = clear_skb ?: tls_strp_msg(ctx);
1576 	clear_skb = NULL;
1577 
1578 	if (unlikely(darg->async)) {
1579 		err = tls_strp_msg_hold(&ctx->strp, &ctx->async_hold);
1580 		if (err)
1581 			__skb_queue_tail(&ctx->async_hold, darg->skb);
1582 		return err;
1583 	}
1584 
1585 	if (prot->tail_size)
1586 		darg->tail = dctx->tail;
1587 
1588 exit_free_pages:
1589 	/* Release the pages in case iov was mapped to pages */
1590 	for (; pages > 0; pages--)
1591 		put_page(sg_page(&sgout[pages]));
1592 exit_free:
1593 	kfree(mem);
1594 exit_free_skb:
1595 	consume_skb(clear_skb);
1596 	return err;
1597 }
1598 
1599 static int
tls_decrypt_sw(struct sock * sk,struct tls_context * tls_ctx,struct msghdr * msg,struct tls_decrypt_arg * darg)1600 tls_decrypt_sw(struct sock *sk, struct tls_context *tls_ctx,
1601 	       struct msghdr *msg, struct tls_decrypt_arg *darg)
1602 {
1603 	struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
1604 	struct tls_prot_info *prot = &tls_ctx->prot_info;
1605 	struct strp_msg *rxm;
1606 	int pad, err;
1607 
1608 	err = tls_decrypt_sg(sk, &msg->msg_iter, NULL, darg);
1609 	if (err < 0) {
1610 		if (err == -EBADMSG)
1611 			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSDECRYPTERROR);
1612 		return err;
1613 	}
1614 	/* keep going even for ->async, the code below is TLS 1.3 */
1615 
1616 	/* If opportunistic TLS 1.3 ZC failed retry without ZC */
1617 	if (unlikely(darg->zc && prot->version == TLS_1_3_VERSION &&
1618 		     darg->tail != TLS_RECORD_TYPE_DATA)) {
1619 		darg->zc = false;
1620 		if (!darg->tail)
1621 			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSRXNOPADVIOL);
1622 		TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSDECRYPTRETRY);
1623 		return tls_decrypt_sw(sk, tls_ctx, msg, darg);
1624 	}
1625 
1626 	pad = tls_padding_length(prot, darg->skb, darg);
1627 	if (pad < 0) {
1628 		if (darg->skb != tls_strp_msg(ctx))
1629 			consume_skb(darg->skb);
1630 		return pad;
1631 	}
1632 
1633 	rxm = strp_msg(darg->skb);
1634 	rxm->full_len -= pad;
1635 
1636 	return 0;
1637 }
1638 
1639 static int
tls_decrypt_device(struct sock * sk,struct msghdr * msg,struct tls_context * tls_ctx,struct tls_decrypt_arg * darg)1640 tls_decrypt_device(struct sock *sk, struct msghdr *msg,
1641 		   struct tls_context *tls_ctx, struct tls_decrypt_arg *darg)
1642 {
1643 	struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
1644 	struct tls_prot_info *prot = &tls_ctx->prot_info;
1645 	struct strp_msg *rxm;
1646 	int pad, err;
1647 
1648 	if (tls_ctx->rx_conf != TLS_HW)
1649 		return 0;
1650 
1651 	err = tls_device_decrypted(sk, tls_ctx);
1652 	if (err <= 0)
1653 		return err;
1654 
1655 	pad = tls_padding_length(prot, tls_strp_msg(ctx), darg);
1656 	if (pad < 0)
1657 		return pad;
1658 
1659 	darg->async = false;
1660 	darg->skb = tls_strp_msg(ctx);
1661 	/* ->zc downgrade check, in case TLS 1.3 gets here */
1662 	darg->zc &= !(prot->version == TLS_1_3_VERSION &&
1663 		      tls_msg(darg->skb)->control != TLS_RECORD_TYPE_DATA);
1664 
1665 	rxm = strp_msg(darg->skb);
1666 	rxm->full_len -= pad;
1667 
1668 	if (!darg->zc) {
1669 		/* Non-ZC case needs a real skb */
1670 		darg->skb = tls_strp_msg_detach(ctx);
1671 		if (!darg->skb)
1672 			return -ENOMEM;
1673 	} else {
1674 		unsigned int off, len;
1675 
1676 		/* In ZC case nobody cares about the output skb.
1677 		 * Just copy the data here. Note the skb is not fully trimmed.
1678 		 */
1679 		off = rxm->offset + prot->prepend_size;
1680 		len = rxm->full_len - prot->overhead_size;
1681 
1682 		err = skb_copy_datagram_msg(darg->skb, off, msg, len);
1683 		if (err)
1684 			return err;
1685 	}
1686 	return 1;
1687 }
1688 
tls_rx_one_record(struct sock * sk,struct msghdr * msg,struct tls_decrypt_arg * darg)1689 static int tls_rx_one_record(struct sock *sk, struct msghdr *msg,
1690 			     struct tls_decrypt_arg *darg)
1691 {
1692 	struct tls_context *tls_ctx = tls_get_ctx(sk);
1693 	struct tls_prot_info *prot = &tls_ctx->prot_info;
1694 	struct strp_msg *rxm;
1695 	int err;
1696 
1697 	err = tls_decrypt_device(sk, msg, tls_ctx, darg);
1698 	if (!err)
1699 		err = tls_decrypt_sw(sk, tls_ctx, msg, darg);
1700 	if (err < 0)
1701 		return err;
1702 
1703 	rxm = strp_msg(darg->skb);
1704 	rxm->offset += prot->prepend_size;
1705 	rxm->full_len -= prot->overhead_size;
1706 	tls_advance_record_sn(sk, prot, &tls_ctx->rx);
1707 
1708 	return 0;
1709 }
1710 
decrypt_skb(struct sock * sk,struct scatterlist * sgout)1711 int decrypt_skb(struct sock *sk, struct scatterlist *sgout)
1712 {
1713 	struct tls_decrypt_arg darg = { .zc = true, };
1714 
1715 	return tls_decrypt_sg(sk, NULL, sgout, &darg);
1716 }
1717 
tls_record_content_type(struct msghdr * msg,struct tls_msg * tlm,u8 * control)1718 static int tls_record_content_type(struct msghdr *msg, struct tls_msg *tlm,
1719 				   u8 *control)
1720 {
1721 	int err;
1722 
1723 	if (!*control) {
1724 		*control = tlm->control;
1725 		if (!*control)
1726 			return -EBADMSG;
1727 
1728 		err = put_cmsg(msg, SOL_TLS, TLS_GET_RECORD_TYPE,
1729 			       sizeof(*control), control);
1730 		if (*control != TLS_RECORD_TYPE_DATA) {
1731 			if (err || msg->msg_flags & MSG_CTRUNC)
1732 				return -EIO;
1733 		}
1734 	} else if (*control != tlm->control) {
1735 		return 0;
1736 	}
1737 
1738 	return 1;
1739 }
1740 
tls_rx_rec_done(struct tls_sw_context_rx * ctx)1741 static void tls_rx_rec_done(struct tls_sw_context_rx *ctx)
1742 {
1743 	tls_strp_msg_done(&ctx->strp);
1744 }
1745 
1746 /* This function traverses the rx_list in tls receive context to copies the
1747  * decrypted records into the buffer provided by caller zero copy is not
1748  * true. Further, the records are removed from the rx_list if it is not a peek
1749  * case and the record has been consumed completely.
1750  */
process_rx_list(struct tls_sw_context_rx * ctx,struct msghdr * msg,u8 * control,size_t skip,size_t len,bool is_peek)1751 static int process_rx_list(struct tls_sw_context_rx *ctx,
1752 			   struct msghdr *msg,
1753 			   u8 *control,
1754 			   size_t skip,
1755 			   size_t len,
1756 			   bool is_peek)
1757 {
1758 	struct sk_buff *skb = skb_peek(&ctx->rx_list);
1759 	struct tls_msg *tlm;
1760 	ssize_t copied = 0;
1761 	int err;
1762 
1763 	while (skip && skb) {
1764 		struct strp_msg *rxm = strp_msg(skb);
1765 		tlm = tls_msg(skb);
1766 
1767 		err = tls_record_content_type(msg, tlm, control);
1768 		if (err <= 0)
1769 			goto out;
1770 
1771 		if (skip < rxm->full_len)
1772 			break;
1773 
1774 		skip = skip - rxm->full_len;
1775 		skb = skb_peek_next(skb, &ctx->rx_list);
1776 	}
1777 
1778 	while (len && skb) {
1779 		struct sk_buff *next_skb;
1780 		struct strp_msg *rxm = strp_msg(skb);
1781 		int chunk = min_t(unsigned int, rxm->full_len - skip, len);
1782 
1783 		tlm = tls_msg(skb);
1784 
1785 		err = tls_record_content_type(msg, tlm, control);
1786 		if (err <= 0)
1787 			goto out;
1788 
1789 		err = skb_copy_datagram_msg(skb, rxm->offset + skip,
1790 					    msg, chunk);
1791 		if (err < 0)
1792 			goto out;
1793 
1794 		len = len - chunk;
1795 		copied = copied + chunk;
1796 
1797 		/* Consume the data from record if it is non-peek case*/
1798 		if (!is_peek) {
1799 			rxm->offset = rxm->offset + chunk;
1800 			rxm->full_len = rxm->full_len - chunk;
1801 
1802 			/* Return if there is unconsumed data in the record */
1803 			if (rxm->full_len - skip)
1804 				break;
1805 		}
1806 
1807 		/* The remaining skip-bytes must lie in 1st record in rx_list.
1808 		 * So from the 2nd record, 'skip' should be 0.
1809 		 */
1810 		skip = 0;
1811 
1812 		if (msg)
1813 			msg->msg_flags |= MSG_EOR;
1814 
1815 		next_skb = skb_peek_next(skb, &ctx->rx_list);
1816 
1817 		if (!is_peek) {
1818 			__skb_unlink(skb, &ctx->rx_list);
1819 			consume_skb(skb);
1820 		}
1821 
1822 		skb = next_skb;
1823 	}
1824 	err = 0;
1825 
1826 out:
1827 	return copied ? : err;
1828 }
1829 
1830 static bool
tls_read_flush_backlog(struct sock * sk,struct tls_prot_info * prot,size_t len_left,size_t decrypted,ssize_t done,size_t * flushed_at)1831 tls_read_flush_backlog(struct sock *sk, struct tls_prot_info *prot,
1832 		       size_t len_left, size_t decrypted, ssize_t done,
1833 		       size_t *flushed_at)
1834 {
1835 	size_t max_rec;
1836 
1837 	if (len_left <= decrypted)
1838 		return false;
1839 
1840 	max_rec = prot->overhead_size - prot->tail_size + TLS_MAX_PAYLOAD_SIZE;
1841 	if (done - *flushed_at < SZ_128K && tcp_inq(sk) > max_rec)
1842 		return false;
1843 
1844 	*flushed_at = done;
1845 	return sk_flush_backlog(sk);
1846 }
1847 
tls_rx_reader_lock(struct sock * sk,struct tls_sw_context_rx * ctx,bool nonblock)1848 static int tls_rx_reader_lock(struct sock *sk, struct tls_sw_context_rx *ctx,
1849 			      bool nonblock)
1850 {
1851 	long timeo;
1852 	int err;
1853 
1854 	lock_sock(sk);
1855 
1856 	timeo = sock_rcvtimeo(sk, nonblock);
1857 
1858 	while (unlikely(ctx->reader_present)) {
1859 		DEFINE_WAIT_FUNC(wait, woken_wake_function);
1860 
1861 		ctx->reader_contended = 1;
1862 
1863 		add_wait_queue(&ctx->wq, &wait);
1864 		sk_wait_event(sk, &timeo,
1865 			      !READ_ONCE(ctx->reader_present), &wait);
1866 		remove_wait_queue(&ctx->wq, &wait);
1867 
1868 		if (timeo <= 0) {
1869 			err = -EAGAIN;
1870 			goto err_unlock;
1871 		}
1872 		if (signal_pending(current)) {
1873 			err = sock_intr_errno(timeo);
1874 			goto err_unlock;
1875 		}
1876 	}
1877 
1878 	WRITE_ONCE(ctx->reader_present, 1);
1879 
1880 	return 0;
1881 
1882 err_unlock:
1883 	release_sock(sk);
1884 	return err;
1885 }
1886 
tls_rx_reader_unlock(struct sock * sk,struct tls_sw_context_rx * ctx)1887 static void tls_rx_reader_unlock(struct sock *sk, struct tls_sw_context_rx *ctx)
1888 {
1889 	if (unlikely(ctx->reader_contended)) {
1890 		if (wq_has_sleeper(&ctx->wq))
1891 			wake_up(&ctx->wq);
1892 		else
1893 			ctx->reader_contended = 0;
1894 
1895 		WARN_ON_ONCE(!ctx->reader_present);
1896 	}
1897 
1898 	WRITE_ONCE(ctx->reader_present, 0);
1899 	release_sock(sk);
1900 }
1901 
tls_sw_recvmsg(struct sock * sk,struct msghdr * msg,size_t len,int flags,int * addr_len)1902 int tls_sw_recvmsg(struct sock *sk,
1903 		   struct msghdr *msg,
1904 		   size_t len,
1905 		   int flags,
1906 		   int *addr_len)
1907 {
1908 	struct tls_context *tls_ctx = tls_get_ctx(sk);
1909 	struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
1910 	struct tls_prot_info *prot = &tls_ctx->prot_info;
1911 	ssize_t decrypted = 0, async_copy_bytes = 0;
1912 	struct sk_psock *psock;
1913 	unsigned char control = 0;
1914 	size_t flushed_at = 0;
1915 	struct strp_msg *rxm;
1916 	struct tls_msg *tlm;
1917 	ssize_t copied = 0;
1918 	bool async = false;
1919 	int target, err;
1920 	bool is_kvec = iov_iter_is_kvec(&msg->msg_iter);
1921 	bool is_peek = flags & MSG_PEEK;
1922 	bool released = true;
1923 	bool bpf_strp_enabled;
1924 	bool zc_capable;
1925 
1926 	if (unlikely(flags & MSG_ERRQUEUE))
1927 		return sock_recv_errqueue(sk, msg, len, SOL_IP, IP_RECVERR);
1928 
1929 	psock = sk_psock_get(sk);
1930 	err = tls_rx_reader_lock(sk, ctx, flags & MSG_DONTWAIT);
1931 	if (err < 0)
1932 		return err;
1933 	bpf_strp_enabled = sk_psock_strp_enabled(psock);
1934 
1935 	/* If crypto failed the connection is broken */
1936 	err = ctx->async_wait.err;
1937 	if (err)
1938 		goto end;
1939 
1940 	/* Process pending decrypted records. It must be non-zero-copy */
1941 	err = process_rx_list(ctx, msg, &control, 0, len, is_peek);
1942 	if (err < 0)
1943 		goto end;
1944 
1945 	copied = err;
1946 	if (len <= copied)
1947 		goto end;
1948 
1949 	target = sock_rcvlowat(sk, flags & MSG_WAITALL, len);
1950 	len = len - copied;
1951 
1952 	zc_capable = !bpf_strp_enabled && !is_kvec && !is_peek &&
1953 		ctx->zc_capable;
1954 	decrypted = 0;
1955 	while (len && (decrypted + copied < target || tls_strp_msg_ready(ctx))) {
1956 		struct tls_decrypt_arg darg;
1957 		int to_decrypt, chunk;
1958 
1959 		err = tls_rx_rec_wait(sk, psock, flags & MSG_DONTWAIT,
1960 				      released);
1961 		if (err <= 0) {
1962 			if (psock) {
1963 				chunk = sk_msg_recvmsg(sk, psock, msg, len,
1964 						       flags);
1965 				if (chunk > 0) {
1966 					decrypted += chunk;
1967 					len -= chunk;
1968 					continue;
1969 				}
1970 			}
1971 			goto recv_end;
1972 		}
1973 
1974 		memset(&darg.inargs, 0, sizeof(darg.inargs));
1975 
1976 		rxm = strp_msg(tls_strp_msg(ctx));
1977 		tlm = tls_msg(tls_strp_msg(ctx));
1978 
1979 		to_decrypt = rxm->full_len - prot->overhead_size;
1980 
1981 		if (zc_capable && to_decrypt <= len &&
1982 		    tlm->control == TLS_RECORD_TYPE_DATA)
1983 			darg.zc = true;
1984 
1985 		/* Do not use async mode if record is non-data */
1986 		if (tlm->control == TLS_RECORD_TYPE_DATA && !bpf_strp_enabled)
1987 			darg.async = ctx->async_capable;
1988 		else
1989 			darg.async = false;
1990 
1991 		err = tls_rx_one_record(sk, msg, &darg);
1992 		if (err < 0) {
1993 			tls_err_abort(sk, -EBADMSG);
1994 			goto recv_end;
1995 		}
1996 
1997 		async |= darg.async;
1998 
1999 		/* If the type of records being processed is not known yet,
2000 		 * set it to record type just dequeued. If it is already known,
2001 		 * but does not match the record type just dequeued, go to end.
2002 		 * We always get record type here since for tls1.2, record type
2003 		 * is known just after record is dequeued from stream parser.
2004 		 * For tls1.3, we disable async.
2005 		 */
2006 		err = tls_record_content_type(msg, tls_msg(darg.skb), &control);
2007 		if (err <= 0) {
2008 			DEBUG_NET_WARN_ON_ONCE(darg.zc);
2009 			tls_rx_rec_done(ctx);
2010 put_on_rx_list_err:
2011 			__skb_queue_tail(&ctx->rx_list, darg.skb);
2012 			goto recv_end;
2013 		}
2014 
2015 		/* periodically flush backlog, and feed strparser */
2016 		released = tls_read_flush_backlog(sk, prot, len, to_decrypt,
2017 						  decrypted + copied,
2018 						  &flushed_at);
2019 
2020 		/* TLS 1.3 may have updated the length by more than overhead */
2021 		rxm = strp_msg(darg.skb);
2022 		chunk = rxm->full_len;
2023 		tls_rx_rec_done(ctx);
2024 
2025 		if (!darg.zc) {
2026 			bool partially_consumed = chunk > len;
2027 			struct sk_buff *skb = darg.skb;
2028 
2029 			DEBUG_NET_WARN_ON_ONCE(darg.skb == ctx->strp.anchor);
2030 
2031 			if (async) {
2032 				/* TLS 1.2-only, to_decrypt must be text len */
2033 				chunk = min_t(int, to_decrypt, len);
2034 				async_copy_bytes += chunk;
2035 put_on_rx_list:
2036 				decrypted += chunk;
2037 				len -= chunk;
2038 				__skb_queue_tail(&ctx->rx_list, skb);
2039 				continue;
2040 			}
2041 
2042 			if (bpf_strp_enabled) {
2043 				released = true;
2044 				err = sk_psock_tls_strp_read(psock, skb);
2045 				if (err != __SK_PASS) {
2046 					rxm->offset = rxm->offset + rxm->full_len;
2047 					rxm->full_len = 0;
2048 					if (err == __SK_DROP)
2049 						consume_skb(skb);
2050 					continue;
2051 				}
2052 			}
2053 
2054 			if (partially_consumed)
2055 				chunk = len;
2056 
2057 			err = skb_copy_datagram_msg(skb, rxm->offset,
2058 						    msg, chunk);
2059 			if (err < 0)
2060 				goto put_on_rx_list_err;
2061 
2062 			if (is_peek)
2063 				goto put_on_rx_list;
2064 
2065 			if (partially_consumed) {
2066 				rxm->offset += chunk;
2067 				rxm->full_len -= chunk;
2068 				goto put_on_rx_list;
2069 			}
2070 
2071 			consume_skb(skb);
2072 		}
2073 
2074 		decrypted += chunk;
2075 		len -= chunk;
2076 
2077 		/* Return full control message to userspace before trying
2078 		 * to parse another message type
2079 		 */
2080 		msg->msg_flags |= MSG_EOR;
2081 		if (control != TLS_RECORD_TYPE_DATA)
2082 			break;
2083 	}
2084 
2085 recv_end:
2086 	if (async) {
2087 		int ret, pending;
2088 
2089 		/* Wait for all previously submitted records to be decrypted */
2090 		spin_lock_bh(&ctx->decrypt_compl_lock);
2091 		reinit_completion(&ctx->async_wait.completion);
2092 		pending = atomic_read(&ctx->decrypt_pending);
2093 		spin_unlock_bh(&ctx->decrypt_compl_lock);
2094 		ret = 0;
2095 		if (pending)
2096 			ret = crypto_wait_req(-EINPROGRESS, &ctx->async_wait);
2097 		__skb_queue_purge(&ctx->async_hold);
2098 
2099 		if (ret) {
2100 			if (err >= 0 || err == -EINPROGRESS)
2101 				err = ret;
2102 			decrypted = 0;
2103 			goto end;
2104 		}
2105 
2106 		/* Drain records from the rx_list & copy if required */
2107 		if (is_peek || is_kvec)
2108 			err = process_rx_list(ctx, msg, &control, copied,
2109 					      decrypted, is_peek);
2110 		else
2111 			err = process_rx_list(ctx, msg, &control, 0,
2112 					      async_copy_bytes, is_peek);
2113 		decrypted = max(err, 0);
2114 	}
2115 
2116 	copied += decrypted;
2117 
2118 end:
2119 	tls_rx_reader_unlock(sk, ctx);
2120 	if (psock)
2121 		sk_psock_put(sk, psock);
2122 	return copied ? : err;
2123 }
2124 
tls_sw_splice_read(struct socket * sock,loff_t * ppos,struct pipe_inode_info * pipe,size_t len,unsigned int flags)2125 ssize_t tls_sw_splice_read(struct socket *sock,  loff_t *ppos,
2126 			   struct pipe_inode_info *pipe,
2127 			   size_t len, unsigned int flags)
2128 {
2129 	struct tls_context *tls_ctx = tls_get_ctx(sock->sk);
2130 	struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
2131 	struct strp_msg *rxm = NULL;
2132 	struct sock *sk = sock->sk;
2133 	struct tls_msg *tlm;
2134 	struct sk_buff *skb;
2135 	ssize_t copied = 0;
2136 	int chunk;
2137 	int err;
2138 
2139 	err = tls_rx_reader_lock(sk, ctx, flags & SPLICE_F_NONBLOCK);
2140 	if (err < 0)
2141 		return err;
2142 
2143 	if (!skb_queue_empty(&ctx->rx_list)) {
2144 		skb = __skb_dequeue(&ctx->rx_list);
2145 	} else {
2146 		struct tls_decrypt_arg darg;
2147 
2148 		err = tls_rx_rec_wait(sk, NULL, flags & SPLICE_F_NONBLOCK,
2149 				      true);
2150 		if (err <= 0)
2151 			goto splice_read_end;
2152 
2153 		memset(&darg.inargs, 0, sizeof(darg.inargs));
2154 
2155 		err = tls_rx_one_record(sk, NULL, &darg);
2156 		if (err < 0) {
2157 			tls_err_abort(sk, -EBADMSG);
2158 			goto splice_read_end;
2159 		}
2160 
2161 		tls_rx_rec_done(ctx);
2162 		skb = darg.skb;
2163 	}
2164 
2165 	rxm = strp_msg(skb);
2166 	tlm = tls_msg(skb);
2167 
2168 	/* splice does not support reading control messages */
2169 	if (tlm->control != TLS_RECORD_TYPE_DATA) {
2170 		err = -EINVAL;
2171 		goto splice_requeue;
2172 	}
2173 
2174 	chunk = min_t(unsigned int, rxm->full_len, len);
2175 	copied = skb_splice_bits(skb, sk, rxm->offset, pipe, chunk, flags);
2176 	if (copied < 0)
2177 		goto splice_requeue;
2178 
2179 	if (chunk < rxm->full_len) {
2180 		rxm->offset += len;
2181 		rxm->full_len -= len;
2182 		goto splice_requeue;
2183 	}
2184 
2185 	consume_skb(skb);
2186 
2187 splice_read_end:
2188 	tls_rx_reader_unlock(sk, ctx);
2189 	return copied ? : err;
2190 
2191 splice_requeue:
2192 	__skb_queue_head(&ctx->rx_list, skb);
2193 	goto splice_read_end;
2194 }
2195 
tls_sw_sock_is_readable(struct sock * sk)2196 bool tls_sw_sock_is_readable(struct sock *sk)
2197 {
2198 	struct tls_context *tls_ctx = tls_get_ctx(sk);
2199 	struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
2200 	bool ingress_empty = true;
2201 	struct sk_psock *psock;
2202 
2203 	rcu_read_lock();
2204 	psock = sk_psock(sk);
2205 	if (psock)
2206 		ingress_empty = list_empty(&psock->ingress_msg);
2207 	rcu_read_unlock();
2208 
2209 	return !ingress_empty || tls_strp_msg_ready(ctx) ||
2210 		!skb_queue_empty(&ctx->rx_list);
2211 }
2212 
tls_rx_msg_size(struct tls_strparser * strp,struct sk_buff * skb)2213 int tls_rx_msg_size(struct tls_strparser *strp, struct sk_buff *skb)
2214 {
2215 	struct tls_context *tls_ctx = tls_get_ctx(strp->sk);
2216 	struct tls_prot_info *prot = &tls_ctx->prot_info;
2217 	char header[TLS_HEADER_SIZE + MAX_IV_SIZE];
2218 	size_t cipher_overhead;
2219 	size_t data_len = 0;
2220 	int ret;
2221 
2222 	/* Verify that we have a full TLS header, or wait for more data */
2223 	if (strp->stm.offset + prot->prepend_size > skb->len)
2224 		return 0;
2225 
2226 	/* Sanity-check size of on-stack buffer. */
2227 	if (WARN_ON(prot->prepend_size > sizeof(header))) {
2228 		ret = -EINVAL;
2229 		goto read_failure;
2230 	}
2231 
2232 	/* Linearize header to local buffer */
2233 	ret = skb_copy_bits(skb, strp->stm.offset, header, prot->prepend_size);
2234 	if (ret < 0)
2235 		goto read_failure;
2236 
2237 	strp->mark = header[0];
2238 
2239 	data_len = ((header[4] & 0xFF) | (header[3] << 8));
2240 
2241 	cipher_overhead = prot->tag_size;
2242 	if (prot->version != TLS_1_3_VERSION &&
2243 	    prot->cipher_type != TLS_CIPHER_CHACHA20_POLY1305)
2244 		cipher_overhead += prot->iv_size;
2245 
2246 	if (data_len > TLS_MAX_PAYLOAD_SIZE + cipher_overhead +
2247 	    prot->tail_size) {
2248 		ret = -EMSGSIZE;
2249 		goto read_failure;
2250 	}
2251 	if (data_len < cipher_overhead) {
2252 		ret = -EBADMSG;
2253 		goto read_failure;
2254 	}
2255 
2256 	/* Note that both TLS1.3 and TLS1.2 use TLS_1_2 version here */
2257 	if (header[1] != TLS_1_2_VERSION_MINOR ||
2258 	    header[2] != TLS_1_2_VERSION_MAJOR) {
2259 		ret = -EINVAL;
2260 		goto read_failure;
2261 	}
2262 
2263 	tls_device_rx_resync_new_rec(strp->sk, data_len + TLS_HEADER_SIZE,
2264 				     TCP_SKB_CB(skb)->seq + strp->stm.offset);
2265 	return data_len + TLS_HEADER_SIZE;
2266 
2267 read_failure:
2268 	tls_err_abort(strp->sk, ret);
2269 
2270 	return ret;
2271 }
2272 
tls_rx_msg_ready(struct tls_strparser * strp)2273 void tls_rx_msg_ready(struct tls_strparser *strp)
2274 {
2275 	struct tls_sw_context_rx *ctx;
2276 
2277 	ctx = container_of(strp, struct tls_sw_context_rx, strp);
2278 	ctx->saved_data_ready(strp->sk);
2279 }
2280 
tls_data_ready(struct sock * sk)2281 static void tls_data_ready(struct sock *sk)
2282 {
2283 	struct tls_context *tls_ctx = tls_get_ctx(sk);
2284 	struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
2285 	struct sk_psock *psock;
2286 
2287 	tls_strp_data_ready(&ctx->strp);
2288 
2289 	psock = sk_psock_get(sk);
2290 	if (psock) {
2291 		if (!list_empty(&psock->ingress_msg))
2292 			ctx->saved_data_ready(sk);
2293 		sk_psock_put(sk, psock);
2294 	}
2295 }
2296 
tls_sw_cancel_work_tx(struct tls_context * tls_ctx)2297 void tls_sw_cancel_work_tx(struct tls_context *tls_ctx)
2298 {
2299 	struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
2300 
2301 	set_bit(BIT_TX_CLOSING, &ctx->tx_bitmask);
2302 	set_bit(BIT_TX_SCHEDULED, &ctx->tx_bitmask);
2303 	cancel_delayed_work_sync(&ctx->tx_work.work);
2304 }
2305 
tls_sw_release_resources_tx(struct sock * sk)2306 void tls_sw_release_resources_tx(struct sock *sk)
2307 {
2308 	struct tls_context *tls_ctx = tls_get_ctx(sk);
2309 	struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
2310 	struct tls_rec *rec, *tmp;
2311 	int pending;
2312 
2313 	/* Wait for any pending async encryptions to complete */
2314 	spin_lock_bh(&ctx->encrypt_compl_lock);
2315 	ctx->async_notify = true;
2316 	pending = atomic_read(&ctx->encrypt_pending);
2317 	spin_unlock_bh(&ctx->encrypt_compl_lock);
2318 
2319 	if (pending)
2320 		crypto_wait_req(-EINPROGRESS, &ctx->async_wait);
2321 
2322 	tls_tx_records(sk, -1);
2323 
2324 	/* Free up un-sent records in tx_list. First, free
2325 	 * the partially sent record if any at head of tx_list.
2326 	 */
2327 	if (tls_ctx->partially_sent_record) {
2328 		tls_free_partial_record(sk, tls_ctx);
2329 		rec = list_first_entry(&ctx->tx_list,
2330 				       struct tls_rec, list);
2331 		list_del(&rec->list);
2332 		sk_msg_free(sk, &rec->msg_plaintext);
2333 		kfree(rec);
2334 	}
2335 
2336 	list_for_each_entry_safe(rec, tmp, &ctx->tx_list, list) {
2337 		list_del(&rec->list);
2338 		sk_msg_free(sk, &rec->msg_encrypted);
2339 		sk_msg_free(sk, &rec->msg_plaintext);
2340 		kfree(rec);
2341 	}
2342 
2343 	crypto_free_aead(ctx->aead_send);
2344 	tls_free_open_rec(sk);
2345 }
2346 
tls_sw_free_ctx_tx(struct tls_context * tls_ctx)2347 void tls_sw_free_ctx_tx(struct tls_context *tls_ctx)
2348 {
2349 	struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
2350 
2351 	kfree(ctx);
2352 }
2353 
tls_sw_release_resources_rx(struct sock * sk)2354 void tls_sw_release_resources_rx(struct sock *sk)
2355 {
2356 	struct tls_context *tls_ctx = tls_get_ctx(sk);
2357 	struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
2358 
2359 	kfree(tls_ctx->rx.rec_seq);
2360 	kfree(tls_ctx->rx.iv);
2361 
2362 	if (ctx->aead_recv) {
2363 		__skb_queue_purge(&ctx->rx_list);
2364 		crypto_free_aead(ctx->aead_recv);
2365 		tls_strp_stop(&ctx->strp);
2366 		/* If tls_sw_strparser_arm() was not called (cleanup paths)
2367 		 * we still want to tls_strp_stop(), but sk->sk_data_ready was
2368 		 * never swapped.
2369 		 */
2370 		if (ctx->saved_data_ready) {
2371 			write_lock_bh(&sk->sk_callback_lock);
2372 			sk->sk_data_ready = ctx->saved_data_ready;
2373 			write_unlock_bh(&sk->sk_callback_lock);
2374 		}
2375 	}
2376 }
2377 
tls_sw_strparser_done(struct tls_context * tls_ctx)2378 void tls_sw_strparser_done(struct tls_context *tls_ctx)
2379 {
2380 	struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
2381 
2382 	tls_strp_done(&ctx->strp);
2383 }
2384 
tls_sw_free_ctx_rx(struct tls_context * tls_ctx)2385 void tls_sw_free_ctx_rx(struct tls_context *tls_ctx)
2386 {
2387 	struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
2388 
2389 	kfree(ctx);
2390 }
2391 
tls_sw_free_resources_rx(struct sock * sk)2392 void tls_sw_free_resources_rx(struct sock *sk)
2393 {
2394 	struct tls_context *tls_ctx = tls_get_ctx(sk);
2395 
2396 	tls_sw_release_resources_rx(sk);
2397 	tls_sw_free_ctx_rx(tls_ctx);
2398 }
2399 
2400 /* The work handler to transmitt the encrypted records in tx_list */
tx_work_handler(struct work_struct * work)2401 static void tx_work_handler(struct work_struct *work)
2402 {
2403 	struct delayed_work *delayed_work = to_delayed_work(work);
2404 	struct tx_work *tx_work = container_of(delayed_work,
2405 					       struct tx_work, work);
2406 	struct sock *sk = tx_work->sk;
2407 	struct tls_context *tls_ctx = tls_get_ctx(sk);
2408 	struct tls_sw_context_tx *ctx;
2409 
2410 	if (unlikely(!tls_ctx))
2411 		return;
2412 
2413 	ctx = tls_sw_ctx_tx(tls_ctx);
2414 	if (test_bit(BIT_TX_CLOSING, &ctx->tx_bitmask))
2415 		return;
2416 
2417 	if (!test_and_clear_bit(BIT_TX_SCHEDULED, &ctx->tx_bitmask))
2418 		return;
2419 	mutex_lock(&tls_ctx->tx_lock);
2420 	lock_sock(sk);
2421 	tls_tx_records(sk, -1);
2422 	release_sock(sk);
2423 	mutex_unlock(&tls_ctx->tx_lock);
2424 }
2425 
tls_is_tx_ready(struct tls_sw_context_tx * ctx)2426 static bool tls_is_tx_ready(struct tls_sw_context_tx *ctx)
2427 {
2428 	struct tls_rec *rec;
2429 
2430 	rec = list_first_entry(&ctx->tx_list, struct tls_rec, list);
2431 	if (!rec)
2432 		return false;
2433 
2434 	return READ_ONCE(rec->tx_ready);
2435 }
2436 
tls_sw_write_space(struct sock * sk,struct tls_context * ctx)2437 void tls_sw_write_space(struct sock *sk, struct tls_context *ctx)
2438 {
2439 	struct tls_sw_context_tx *tx_ctx = tls_sw_ctx_tx(ctx);
2440 
2441 	/* Schedule the transmission if tx list is ready */
2442 	if (tls_is_tx_ready(tx_ctx) &&
2443 	    !test_and_set_bit(BIT_TX_SCHEDULED, &tx_ctx->tx_bitmask))
2444 		schedule_delayed_work(&tx_ctx->tx_work.work, 0);
2445 }
2446 
tls_sw_strparser_arm(struct sock * sk,struct tls_context * tls_ctx)2447 void tls_sw_strparser_arm(struct sock *sk, struct tls_context *tls_ctx)
2448 {
2449 	struct tls_sw_context_rx *rx_ctx = tls_sw_ctx_rx(tls_ctx);
2450 
2451 	write_lock_bh(&sk->sk_callback_lock);
2452 	rx_ctx->saved_data_ready = sk->sk_data_ready;
2453 	sk->sk_data_ready = tls_data_ready;
2454 	write_unlock_bh(&sk->sk_callback_lock);
2455 }
2456 
tls_update_rx_zc_capable(struct tls_context * tls_ctx)2457 void tls_update_rx_zc_capable(struct tls_context *tls_ctx)
2458 {
2459 	struct tls_sw_context_rx *rx_ctx = tls_sw_ctx_rx(tls_ctx);
2460 
2461 	rx_ctx->zc_capable = tls_ctx->rx_no_pad ||
2462 		tls_ctx->prot_info.version != TLS_1_3_VERSION;
2463 }
2464 
tls_set_sw_offload(struct sock * sk,struct tls_context * ctx,int tx)2465 int tls_set_sw_offload(struct sock *sk, struct tls_context *ctx, int tx)
2466 {
2467 	struct tls_context *tls_ctx = tls_get_ctx(sk);
2468 	struct tls_prot_info *prot = &tls_ctx->prot_info;
2469 	struct tls_crypto_info *crypto_info;
2470 	struct tls_sw_context_tx *sw_ctx_tx = NULL;
2471 	struct tls_sw_context_rx *sw_ctx_rx = NULL;
2472 	struct cipher_context *cctx;
2473 	struct crypto_aead **aead;
2474 	u16 nonce_size, tag_size, iv_size, rec_seq_size, salt_size;
2475 	struct crypto_tfm *tfm;
2476 	char *iv, *rec_seq, *key, *salt, *cipher_name;
2477 	size_t keysize;
2478 	int rc = 0;
2479 
2480 	if (!ctx) {
2481 		rc = -EINVAL;
2482 		goto out;
2483 	}
2484 
2485 	if (tx) {
2486 		if (!ctx->priv_ctx_tx) {
2487 			sw_ctx_tx = kzalloc(sizeof(*sw_ctx_tx), GFP_KERNEL);
2488 			if (!sw_ctx_tx) {
2489 				rc = -ENOMEM;
2490 				goto out;
2491 			}
2492 			ctx->priv_ctx_tx = sw_ctx_tx;
2493 		} else {
2494 			sw_ctx_tx =
2495 				(struct tls_sw_context_tx *)ctx->priv_ctx_tx;
2496 		}
2497 	} else {
2498 		if (!ctx->priv_ctx_rx) {
2499 			sw_ctx_rx = kzalloc(sizeof(*sw_ctx_rx), GFP_KERNEL);
2500 			if (!sw_ctx_rx) {
2501 				rc = -ENOMEM;
2502 				goto out;
2503 			}
2504 			ctx->priv_ctx_rx = sw_ctx_rx;
2505 		} else {
2506 			sw_ctx_rx =
2507 				(struct tls_sw_context_rx *)ctx->priv_ctx_rx;
2508 		}
2509 	}
2510 
2511 	if (tx) {
2512 		crypto_init_wait(&sw_ctx_tx->async_wait);
2513 		spin_lock_init(&sw_ctx_tx->encrypt_compl_lock);
2514 		crypto_info = &ctx->crypto_send.info;
2515 		cctx = &ctx->tx;
2516 		aead = &sw_ctx_tx->aead_send;
2517 		INIT_LIST_HEAD(&sw_ctx_tx->tx_list);
2518 		INIT_DELAYED_WORK(&sw_ctx_tx->tx_work.work, tx_work_handler);
2519 		sw_ctx_tx->tx_work.sk = sk;
2520 	} else {
2521 		crypto_init_wait(&sw_ctx_rx->async_wait);
2522 		spin_lock_init(&sw_ctx_rx->decrypt_compl_lock);
2523 		init_waitqueue_head(&sw_ctx_rx->wq);
2524 		crypto_info = &ctx->crypto_recv.info;
2525 		cctx = &ctx->rx;
2526 		skb_queue_head_init(&sw_ctx_rx->rx_list);
2527 		skb_queue_head_init(&sw_ctx_rx->async_hold);
2528 		aead = &sw_ctx_rx->aead_recv;
2529 	}
2530 
2531 	switch (crypto_info->cipher_type) {
2532 	case TLS_CIPHER_AES_GCM_128: {
2533 		struct tls12_crypto_info_aes_gcm_128 *gcm_128_info;
2534 
2535 		gcm_128_info = (void *)crypto_info;
2536 		nonce_size = TLS_CIPHER_AES_GCM_128_IV_SIZE;
2537 		tag_size = TLS_CIPHER_AES_GCM_128_TAG_SIZE;
2538 		iv_size = TLS_CIPHER_AES_GCM_128_IV_SIZE;
2539 		iv = gcm_128_info->iv;
2540 		rec_seq_size = TLS_CIPHER_AES_GCM_128_REC_SEQ_SIZE;
2541 		rec_seq = gcm_128_info->rec_seq;
2542 		keysize = TLS_CIPHER_AES_GCM_128_KEY_SIZE;
2543 		key = gcm_128_info->key;
2544 		salt = gcm_128_info->salt;
2545 		salt_size = TLS_CIPHER_AES_GCM_128_SALT_SIZE;
2546 		cipher_name = "gcm(aes)";
2547 		break;
2548 	}
2549 	case TLS_CIPHER_AES_GCM_256: {
2550 		struct tls12_crypto_info_aes_gcm_256 *gcm_256_info;
2551 
2552 		gcm_256_info = (void *)crypto_info;
2553 		nonce_size = TLS_CIPHER_AES_GCM_256_IV_SIZE;
2554 		tag_size = TLS_CIPHER_AES_GCM_256_TAG_SIZE;
2555 		iv_size = TLS_CIPHER_AES_GCM_256_IV_SIZE;
2556 		iv = gcm_256_info->iv;
2557 		rec_seq_size = TLS_CIPHER_AES_GCM_256_REC_SEQ_SIZE;
2558 		rec_seq = gcm_256_info->rec_seq;
2559 		keysize = TLS_CIPHER_AES_GCM_256_KEY_SIZE;
2560 		key = gcm_256_info->key;
2561 		salt = gcm_256_info->salt;
2562 		salt_size = TLS_CIPHER_AES_GCM_256_SALT_SIZE;
2563 		cipher_name = "gcm(aes)";
2564 		break;
2565 	}
2566 	case TLS_CIPHER_AES_CCM_128: {
2567 		struct tls12_crypto_info_aes_ccm_128 *ccm_128_info;
2568 
2569 		ccm_128_info = (void *)crypto_info;
2570 		nonce_size = TLS_CIPHER_AES_CCM_128_IV_SIZE;
2571 		tag_size = TLS_CIPHER_AES_CCM_128_TAG_SIZE;
2572 		iv_size = TLS_CIPHER_AES_CCM_128_IV_SIZE;
2573 		iv = ccm_128_info->iv;
2574 		rec_seq_size = TLS_CIPHER_AES_CCM_128_REC_SEQ_SIZE;
2575 		rec_seq = ccm_128_info->rec_seq;
2576 		keysize = TLS_CIPHER_AES_CCM_128_KEY_SIZE;
2577 		key = ccm_128_info->key;
2578 		salt = ccm_128_info->salt;
2579 		salt_size = TLS_CIPHER_AES_CCM_128_SALT_SIZE;
2580 		cipher_name = "ccm(aes)";
2581 		break;
2582 	}
2583 	case TLS_CIPHER_CHACHA20_POLY1305: {
2584 		struct tls12_crypto_info_chacha20_poly1305 *chacha20_poly1305_info;
2585 
2586 		chacha20_poly1305_info = (void *)crypto_info;
2587 		nonce_size = 0;
2588 		tag_size = TLS_CIPHER_CHACHA20_POLY1305_TAG_SIZE;
2589 		iv_size = TLS_CIPHER_CHACHA20_POLY1305_IV_SIZE;
2590 		iv = chacha20_poly1305_info->iv;
2591 		rec_seq_size = TLS_CIPHER_CHACHA20_POLY1305_REC_SEQ_SIZE;
2592 		rec_seq = chacha20_poly1305_info->rec_seq;
2593 		keysize = TLS_CIPHER_CHACHA20_POLY1305_KEY_SIZE;
2594 		key = chacha20_poly1305_info->key;
2595 		salt = chacha20_poly1305_info->salt;
2596 		salt_size = TLS_CIPHER_CHACHA20_POLY1305_SALT_SIZE;
2597 		cipher_name = "rfc7539(chacha20,poly1305)";
2598 		break;
2599 	}
2600 	case TLS_CIPHER_SM4_GCM: {
2601 		struct tls12_crypto_info_sm4_gcm *sm4_gcm_info;
2602 
2603 		sm4_gcm_info = (void *)crypto_info;
2604 		nonce_size = TLS_CIPHER_SM4_GCM_IV_SIZE;
2605 		tag_size = TLS_CIPHER_SM4_GCM_TAG_SIZE;
2606 		iv_size = TLS_CIPHER_SM4_GCM_IV_SIZE;
2607 		iv = sm4_gcm_info->iv;
2608 		rec_seq_size = TLS_CIPHER_SM4_GCM_REC_SEQ_SIZE;
2609 		rec_seq = sm4_gcm_info->rec_seq;
2610 		keysize = TLS_CIPHER_SM4_GCM_KEY_SIZE;
2611 		key = sm4_gcm_info->key;
2612 		salt = sm4_gcm_info->salt;
2613 		salt_size = TLS_CIPHER_SM4_GCM_SALT_SIZE;
2614 		cipher_name = "gcm(sm4)";
2615 		break;
2616 	}
2617 	case TLS_CIPHER_SM4_CCM: {
2618 		struct tls12_crypto_info_sm4_ccm *sm4_ccm_info;
2619 
2620 		sm4_ccm_info = (void *)crypto_info;
2621 		nonce_size = TLS_CIPHER_SM4_CCM_IV_SIZE;
2622 		tag_size = TLS_CIPHER_SM4_CCM_TAG_SIZE;
2623 		iv_size = TLS_CIPHER_SM4_CCM_IV_SIZE;
2624 		iv = sm4_ccm_info->iv;
2625 		rec_seq_size = TLS_CIPHER_SM4_CCM_REC_SEQ_SIZE;
2626 		rec_seq = sm4_ccm_info->rec_seq;
2627 		keysize = TLS_CIPHER_SM4_CCM_KEY_SIZE;
2628 		key = sm4_ccm_info->key;
2629 		salt = sm4_ccm_info->salt;
2630 		salt_size = TLS_CIPHER_SM4_CCM_SALT_SIZE;
2631 		cipher_name = "ccm(sm4)";
2632 		break;
2633 	}
2634 	case TLS_CIPHER_ARIA_GCM_128: {
2635 		struct tls12_crypto_info_aria_gcm_128 *aria_gcm_128_info;
2636 
2637 		aria_gcm_128_info = (void *)crypto_info;
2638 		nonce_size = TLS_CIPHER_ARIA_GCM_128_IV_SIZE;
2639 		tag_size = TLS_CIPHER_ARIA_GCM_128_TAG_SIZE;
2640 		iv_size = TLS_CIPHER_ARIA_GCM_128_IV_SIZE;
2641 		iv = aria_gcm_128_info->iv;
2642 		rec_seq_size = TLS_CIPHER_ARIA_GCM_128_REC_SEQ_SIZE;
2643 		rec_seq = aria_gcm_128_info->rec_seq;
2644 		keysize = TLS_CIPHER_ARIA_GCM_128_KEY_SIZE;
2645 		key = aria_gcm_128_info->key;
2646 		salt = aria_gcm_128_info->salt;
2647 		salt_size = TLS_CIPHER_ARIA_GCM_128_SALT_SIZE;
2648 		cipher_name = "gcm(aria)";
2649 		break;
2650 	}
2651 	case TLS_CIPHER_ARIA_GCM_256: {
2652 		struct tls12_crypto_info_aria_gcm_256 *gcm_256_info;
2653 
2654 		gcm_256_info = (void *)crypto_info;
2655 		nonce_size = TLS_CIPHER_ARIA_GCM_256_IV_SIZE;
2656 		tag_size = TLS_CIPHER_ARIA_GCM_256_TAG_SIZE;
2657 		iv_size = TLS_CIPHER_ARIA_GCM_256_IV_SIZE;
2658 		iv = gcm_256_info->iv;
2659 		rec_seq_size = TLS_CIPHER_ARIA_GCM_256_REC_SEQ_SIZE;
2660 		rec_seq = gcm_256_info->rec_seq;
2661 		keysize = TLS_CIPHER_ARIA_GCM_256_KEY_SIZE;
2662 		key = gcm_256_info->key;
2663 		salt = gcm_256_info->salt;
2664 		salt_size = TLS_CIPHER_ARIA_GCM_256_SALT_SIZE;
2665 		cipher_name = "gcm(aria)";
2666 		break;
2667 	}
2668 	default:
2669 		rc = -EINVAL;
2670 		goto free_priv;
2671 	}
2672 
2673 	if (crypto_info->version == TLS_1_3_VERSION) {
2674 		nonce_size = 0;
2675 		prot->aad_size = TLS_HEADER_SIZE;
2676 		prot->tail_size = 1;
2677 	} else {
2678 		prot->aad_size = TLS_AAD_SPACE_SIZE;
2679 		prot->tail_size = 0;
2680 	}
2681 
2682 	/* Sanity-check the sizes for stack allocations. */
2683 	if (iv_size > MAX_IV_SIZE || nonce_size > MAX_IV_SIZE ||
2684 	    rec_seq_size > TLS_MAX_REC_SEQ_SIZE || tag_size != TLS_TAG_SIZE ||
2685 	    prot->aad_size > TLS_MAX_AAD_SIZE) {
2686 		rc = -EINVAL;
2687 		goto free_priv;
2688 	}
2689 
2690 	prot->version = crypto_info->version;
2691 	prot->cipher_type = crypto_info->cipher_type;
2692 	prot->prepend_size = TLS_HEADER_SIZE + nonce_size;
2693 	prot->tag_size = tag_size;
2694 	prot->overhead_size = prot->prepend_size +
2695 			      prot->tag_size + prot->tail_size;
2696 	prot->iv_size = iv_size;
2697 	prot->salt_size = salt_size;
2698 	cctx->iv = kmalloc(iv_size + salt_size, GFP_KERNEL);
2699 	if (!cctx->iv) {
2700 		rc = -ENOMEM;
2701 		goto free_priv;
2702 	}
2703 	/* Note: 128 & 256 bit salt are the same size */
2704 	prot->rec_seq_size = rec_seq_size;
2705 	memcpy(cctx->iv, salt, salt_size);
2706 	memcpy(cctx->iv + salt_size, iv, iv_size);
2707 	cctx->rec_seq = kmemdup(rec_seq, rec_seq_size, GFP_KERNEL);
2708 	if (!cctx->rec_seq) {
2709 		rc = -ENOMEM;
2710 		goto free_iv;
2711 	}
2712 
2713 	if (!*aead) {
2714 		*aead = crypto_alloc_aead(cipher_name, 0, 0);
2715 		if (IS_ERR(*aead)) {
2716 			rc = PTR_ERR(*aead);
2717 			*aead = NULL;
2718 			goto free_rec_seq;
2719 		}
2720 	}
2721 
2722 	ctx->push_pending_record = tls_sw_push_pending_record;
2723 
2724 	rc = crypto_aead_setkey(*aead, key, keysize);
2725 
2726 	if (rc)
2727 		goto free_aead;
2728 
2729 	rc = crypto_aead_setauthsize(*aead, prot->tag_size);
2730 	if (rc)
2731 		goto free_aead;
2732 
2733 	if (sw_ctx_rx) {
2734 		tfm = crypto_aead_tfm(sw_ctx_rx->aead_recv);
2735 
2736 		tls_update_rx_zc_capable(ctx);
2737 		sw_ctx_rx->async_capable =
2738 			crypto_info->version != TLS_1_3_VERSION &&
2739 			!!(tfm->__crt_alg->cra_flags & CRYPTO_ALG_ASYNC);
2740 
2741 		rc = tls_strp_init(&sw_ctx_rx->strp, sk);
2742 		if (rc)
2743 			goto free_aead;
2744 	}
2745 
2746 	goto out;
2747 
2748 free_aead:
2749 	crypto_free_aead(*aead);
2750 	*aead = NULL;
2751 free_rec_seq:
2752 	kfree(cctx->rec_seq);
2753 	cctx->rec_seq = NULL;
2754 free_iv:
2755 	kfree(cctx->iv);
2756 	cctx->iv = NULL;
2757 free_priv:
2758 	if (tx) {
2759 		kfree(ctx->priv_ctx_tx);
2760 		ctx->priv_ctx_tx = NULL;
2761 	} else {
2762 		kfree(ctx->priv_ctx_rx);
2763 		ctx->priv_ctx_rx = NULL;
2764 	}
2765 out:
2766 	return rc;
2767 }
2768