xref: /kernel/linux/linux-5.10/net/tls/tls_sw.c (revision 8c2ecf20)
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
47noinline void tls_err_abort(struct sock *sk, int err)
48{
49	WARN_ON_ONCE(err >= 0);
50	/* sk->sk_err should contain a positive error code. */
51	sk->sk_err = -err;
52	sk->sk_error_report(sk);
53}
54
55static int __skb_nsg(struct sk_buff *skb, int offset, int len,
56                     unsigned int recursion_level)
57{
58        int start = skb_headlen(skb);
59        int i, chunk = start - offset;
60        struct sk_buff *frag_iter;
61        int elt = 0;
62
63        if (unlikely(recursion_level >= 24))
64                return -EMSGSIZE;
65
66        if (chunk > 0) {
67                if (chunk > len)
68                        chunk = len;
69                elt++;
70                len -= chunk;
71                if (len == 0)
72                        return elt;
73                offset += chunk;
74        }
75
76        for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
77                int end;
78
79                WARN_ON(start > offset + len);
80
81                end = start + skb_frag_size(&skb_shinfo(skb)->frags[i]);
82                chunk = end - offset;
83                if (chunk > 0) {
84                        if (chunk > len)
85                                chunk = len;
86                        elt++;
87                        len -= chunk;
88                        if (len == 0)
89                                return elt;
90                        offset += chunk;
91                }
92                start = end;
93        }
94
95        if (unlikely(skb_has_frag_list(skb))) {
96                skb_walk_frags(skb, frag_iter) {
97                        int end, ret;
98
99                        WARN_ON(start > offset + len);
100
101                        end = start + frag_iter->len;
102                        chunk = end - offset;
103                        if (chunk > 0) {
104                                if (chunk > len)
105                                        chunk = len;
106                                ret = __skb_nsg(frag_iter, offset - start, chunk,
107                                                recursion_level + 1);
108                                if (unlikely(ret < 0))
109                                        return ret;
110                                elt += ret;
111                                len -= chunk;
112                                if (len == 0)
113                                        return elt;
114                                offset += chunk;
115                        }
116                        start = end;
117                }
118        }
119        BUG_ON(len);
120        return elt;
121}
122
123/* Return the number of scatterlist elements required to completely map the
124 * skb, or -EMSGSIZE if the recursion depth is exceeded.
125 */
126static int skb_nsg(struct sk_buff *skb, int offset, int len)
127{
128        return __skb_nsg(skb, offset, len, 0);
129}
130
131static int padding_length(struct tls_sw_context_rx *ctx,
132			  struct tls_prot_info *prot, struct sk_buff *skb)
133{
134	struct strp_msg *rxm = strp_msg(skb);
135	int sub = 0;
136
137	/* Determine zero-padding length */
138	if (prot->version == TLS_1_3_VERSION) {
139		char content_type = 0;
140		int err;
141		int back = 17;
142
143		while (content_type == 0) {
144			if (back > rxm->full_len - prot->prepend_size)
145				return -EBADMSG;
146			err = skb_copy_bits(skb,
147					    rxm->offset + rxm->full_len - back,
148					    &content_type, 1);
149			if (err)
150				return err;
151			if (content_type)
152				break;
153			sub++;
154			back++;
155		}
156		ctx->control = content_type;
157	}
158	return sub;
159}
160
161static void tls_decrypt_done(struct crypto_async_request *req, int err)
162{
163	struct aead_request *aead_req = (struct aead_request *)req;
164	struct scatterlist *sgout = aead_req->dst;
165	struct scatterlist *sgin = aead_req->src;
166	struct tls_sw_context_rx *ctx;
167	struct tls_context *tls_ctx;
168	struct tls_prot_info *prot;
169	struct scatterlist *sg;
170	struct sk_buff *skb;
171	unsigned int pages;
172	int pending;
173
174	skb = (struct sk_buff *)req->data;
175	tls_ctx = tls_get_ctx(skb->sk);
176	ctx = tls_sw_ctx_rx(tls_ctx);
177	prot = &tls_ctx->prot_info;
178
179	/* Propagate if there was an err */
180	if (err) {
181		if (err == -EBADMSG)
182			TLS_INC_STATS(sock_net(skb->sk),
183				      LINUX_MIB_TLSDECRYPTERROR);
184		ctx->async_wait.err = err;
185		tls_err_abort(skb->sk, err);
186	} else {
187		struct strp_msg *rxm = strp_msg(skb);
188		int pad;
189
190		pad = padding_length(ctx, prot, skb);
191		if (pad < 0) {
192			ctx->async_wait.err = pad;
193			tls_err_abort(skb->sk, pad);
194		} else {
195			rxm->full_len -= pad;
196			rxm->offset += prot->prepend_size;
197			rxm->full_len -= prot->overhead_size;
198		}
199	}
200
201	/* After using skb->sk to propagate sk through crypto async callback
202	 * we need to NULL it again.
203	 */
204	skb->sk = NULL;
205
206
207	/* Free the destination pages if skb was not decrypted inplace */
208	if (sgout != sgin) {
209		/* Skip the first S/G entry as it points to AAD */
210		for_each_sg(sg_next(sgout), sg, UINT_MAX, pages) {
211			if (!sg)
212				break;
213			put_page(sg_page(sg));
214		}
215	}
216
217	kfree(aead_req);
218
219	spin_lock_bh(&ctx->decrypt_compl_lock);
220	pending = atomic_dec_return(&ctx->decrypt_pending);
221
222	if (!pending && ctx->async_notify)
223		complete(&ctx->async_wait.completion);
224	spin_unlock_bh(&ctx->decrypt_compl_lock);
225}
226
227static int tls_do_decryption(struct sock *sk,
228			     struct sk_buff *skb,
229			     struct scatterlist *sgin,
230			     struct scatterlist *sgout,
231			     char *iv_recv,
232			     size_t data_len,
233			     struct aead_request *aead_req,
234			     bool async)
235{
236	struct tls_context *tls_ctx = tls_get_ctx(sk);
237	struct tls_prot_info *prot = &tls_ctx->prot_info;
238	struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
239	int ret;
240
241	aead_request_set_tfm(aead_req, ctx->aead_recv);
242	aead_request_set_ad(aead_req, prot->aad_size);
243	aead_request_set_crypt(aead_req, sgin, sgout,
244			       data_len + prot->tag_size,
245			       (u8 *)iv_recv);
246
247	if (async) {
248		/* Using skb->sk to push sk through to crypto async callback
249		 * handler. This allows propagating errors up to the socket
250		 * if needed. It _must_ be cleared in the async handler
251		 * before consume_skb is called. We _know_ skb->sk is NULL
252		 * because it is a clone from strparser.
253		 */
254		skb->sk = sk;
255		aead_request_set_callback(aead_req,
256					  CRYPTO_TFM_REQ_MAY_BACKLOG,
257					  tls_decrypt_done, skb);
258		atomic_inc(&ctx->decrypt_pending);
259	} else {
260		aead_request_set_callback(aead_req,
261					  CRYPTO_TFM_REQ_MAY_BACKLOG,
262					  crypto_req_done, &ctx->async_wait);
263	}
264
265	ret = crypto_aead_decrypt(aead_req);
266	if (ret == -EINPROGRESS) {
267		if (async)
268			return ret;
269
270		ret = crypto_wait_req(ret, &ctx->async_wait);
271	}
272
273	if (async)
274		atomic_dec(&ctx->decrypt_pending);
275
276	return ret;
277}
278
279static void tls_trim_both_msgs(struct sock *sk, int target_size)
280{
281	struct tls_context *tls_ctx = tls_get_ctx(sk);
282	struct tls_prot_info *prot = &tls_ctx->prot_info;
283	struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
284	struct tls_rec *rec = ctx->open_rec;
285
286	sk_msg_trim(sk, &rec->msg_plaintext, target_size);
287	if (target_size > 0)
288		target_size += prot->overhead_size;
289	sk_msg_trim(sk, &rec->msg_encrypted, target_size);
290}
291
292static int tls_alloc_encrypted_msg(struct sock *sk, int len)
293{
294	struct tls_context *tls_ctx = tls_get_ctx(sk);
295	struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
296	struct tls_rec *rec = ctx->open_rec;
297	struct sk_msg *msg_en = &rec->msg_encrypted;
298
299	return sk_msg_alloc(sk, msg_en, len, 0);
300}
301
302static int tls_clone_plaintext_msg(struct sock *sk, int required)
303{
304	struct tls_context *tls_ctx = tls_get_ctx(sk);
305	struct tls_prot_info *prot = &tls_ctx->prot_info;
306	struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
307	struct tls_rec *rec = ctx->open_rec;
308	struct sk_msg *msg_pl = &rec->msg_plaintext;
309	struct sk_msg *msg_en = &rec->msg_encrypted;
310	int skip, len;
311
312	/* We add page references worth len bytes from encrypted sg
313	 * at the end of plaintext sg. It is guaranteed that msg_en
314	 * has enough required room (ensured by caller).
315	 */
316	len = required - msg_pl->sg.size;
317
318	/* Skip initial bytes in msg_en's data to be able to use
319	 * same offset of both plain and encrypted data.
320	 */
321	skip = prot->prepend_size + msg_pl->sg.size;
322
323	return sk_msg_clone(sk, msg_pl, msg_en, skip, len);
324}
325
326static struct tls_rec *tls_get_rec(struct sock *sk)
327{
328	struct tls_context *tls_ctx = tls_get_ctx(sk);
329	struct tls_prot_info *prot = &tls_ctx->prot_info;
330	struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
331	struct sk_msg *msg_pl, *msg_en;
332	struct tls_rec *rec;
333	int mem_size;
334
335	mem_size = sizeof(struct tls_rec) + crypto_aead_reqsize(ctx->aead_send);
336
337	rec = kzalloc(mem_size, sk->sk_allocation);
338	if (!rec)
339		return NULL;
340
341	msg_pl = &rec->msg_plaintext;
342	msg_en = &rec->msg_encrypted;
343
344	sk_msg_init(msg_pl);
345	sk_msg_init(msg_en);
346
347	sg_init_table(rec->sg_aead_in, 2);
348	sg_set_buf(&rec->sg_aead_in[0], rec->aad_space, prot->aad_size);
349	sg_unmark_end(&rec->sg_aead_in[1]);
350
351	sg_init_table(rec->sg_aead_out, 2);
352	sg_set_buf(&rec->sg_aead_out[0], rec->aad_space, prot->aad_size);
353	sg_unmark_end(&rec->sg_aead_out[1]);
354
355	return rec;
356}
357
358static void tls_free_rec(struct sock *sk, struct tls_rec *rec)
359{
360	sk_msg_free(sk, &rec->msg_encrypted);
361	sk_msg_free(sk, &rec->msg_plaintext);
362	kfree(rec);
363}
364
365static void tls_free_open_rec(struct sock *sk)
366{
367	struct tls_context *tls_ctx = tls_get_ctx(sk);
368	struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
369	struct tls_rec *rec = ctx->open_rec;
370
371	if (rec) {
372		tls_free_rec(sk, rec);
373		ctx->open_rec = NULL;
374	}
375}
376
377int tls_tx_records(struct sock *sk, int flags)
378{
379	struct tls_context *tls_ctx = tls_get_ctx(sk);
380	struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
381	struct tls_rec *rec, *tmp;
382	struct sk_msg *msg_en;
383	int tx_flags, rc = 0;
384
385	if (tls_is_partially_sent_record(tls_ctx)) {
386		rec = list_first_entry(&ctx->tx_list,
387				       struct tls_rec, list);
388
389		if (flags == -1)
390			tx_flags = rec->tx_flags;
391		else
392			tx_flags = flags;
393
394		rc = tls_push_partial_record(sk, tls_ctx, tx_flags);
395		if (rc)
396			goto tx_err;
397
398		/* Full record has been transmitted.
399		 * Remove the head of tx_list
400		 */
401		list_del(&rec->list);
402		sk_msg_free(sk, &rec->msg_plaintext);
403		kfree(rec);
404	}
405
406	/* Tx all ready records */
407	list_for_each_entry_safe(rec, tmp, &ctx->tx_list, list) {
408		if (READ_ONCE(rec->tx_ready)) {
409			if (flags == -1)
410				tx_flags = rec->tx_flags;
411			else
412				tx_flags = flags;
413
414			msg_en = &rec->msg_encrypted;
415			rc = tls_push_sg(sk, tls_ctx,
416					 &msg_en->sg.data[msg_en->sg.curr],
417					 0, tx_flags);
418			if (rc)
419				goto tx_err;
420
421			list_del(&rec->list);
422			sk_msg_free(sk, &rec->msg_plaintext);
423			kfree(rec);
424		} else {
425			break;
426		}
427	}
428
429tx_err:
430	if (rc < 0 && rc != -EAGAIN)
431		tls_err_abort(sk, -EBADMSG);
432
433	return rc;
434}
435
436static void tls_encrypt_done(struct crypto_async_request *req, int err)
437{
438	struct aead_request *aead_req = (struct aead_request *)req;
439	struct sock *sk = req->data;
440	struct tls_context *tls_ctx = tls_get_ctx(sk);
441	struct tls_prot_info *prot = &tls_ctx->prot_info;
442	struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
443	struct scatterlist *sge;
444	struct sk_msg *msg_en;
445	struct tls_rec *rec;
446	int pending;
447
448	rec = container_of(aead_req, struct tls_rec, aead_req);
449	msg_en = &rec->msg_encrypted;
450
451	sge = sk_msg_elem(msg_en, msg_en->sg.curr);
452	sge->offset -= prot->prepend_size;
453	sge->length += prot->prepend_size;
454
455	/* Check if error is previously set on socket */
456	if (err || sk->sk_err) {
457		rec = NULL;
458
459		/* If err is already set on socket, return the same code */
460		if (sk->sk_err) {
461			ctx->async_wait.err = -sk->sk_err;
462		} else {
463			ctx->async_wait.err = err;
464			tls_err_abort(sk, err);
465		}
466	}
467
468	if (rec) {
469		struct tls_rec *first_rec;
470
471		/* Mark the record as ready for transmission */
472		smp_store_mb(rec->tx_ready, true);
473
474		/* If received record is at head of tx_list, schedule tx */
475		first_rec = list_first_entry(&ctx->tx_list,
476					     struct tls_rec, list);
477		if (rec == first_rec) {
478			/* Schedule the transmission */
479			if (!test_and_set_bit(BIT_TX_SCHEDULED,
480					      &ctx->tx_bitmask))
481				schedule_delayed_work(&ctx->tx_work.work, 1);
482		}
483	}
484
485	spin_lock_bh(&ctx->encrypt_compl_lock);
486	pending = atomic_dec_return(&ctx->encrypt_pending);
487
488	if (!pending && ctx->async_notify)
489		complete(&ctx->async_wait.completion);
490	spin_unlock_bh(&ctx->encrypt_compl_lock);
491}
492
493static int tls_do_encryption(struct sock *sk,
494			     struct tls_context *tls_ctx,
495			     struct tls_sw_context_tx *ctx,
496			     struct aead_request *aead_req,
497			     size_t data_len, u32 start)
498{
499	struct tls_prot_info *prot = &tls_ctx->prot_info;
500	struct tls_rec *rec = ctx->open_rec;
501	struct sk_msg *msg_en = &rec->msg_encrypted;
502	struct scatterlist *sge = sk_msg_elem(msg_en, start);
503	int rc, iv_offset = 0;
504
505	/* For CCM based ciphers, first byte of IV is a constant */
506	if (prot->cipher_type == TLS_CIPHER_AES_CCM_128) {
507		rec->iv_data[0] = TLS_AES_CCM_IV_B0_BYTE;
508		iv_offset = 1;
509	}
510
511	memcpy(&rec->iv_data[iv_offset], tls_ctx->tx.iv,
512	       prot->iv_size + prot->salt_size);
513
514	xor_iv_with_seq(prot->version, rec->iv_data + iv_offset, tls_ctx->tx.rec_seq);
515
516	sge->offset += prot->prepend_size;
517	sge->length -= prot->prepend_size;
518
519	msg_en->sg.curr = start;
520
521	aead_request_set_tfm(aead_req, ctx->aead_send);
522	aead_request_set_ad(aead_req, prot->aad_size);
523	aead_request_set_crypt(aead_req, rec->sg_aead_in,
524			       rec->sg_aead_out,
525			       data_len, rec->iv_data);
526
527	aead_request_set_callback(aead_req, CRYPTO_TFM_REQ_MAY_BACKLOG,
528				  tls_encrypt_done, sk);
529
530	/* Add the record in tx_list */
531	list_add_tail((struct list_head *)&rec->list, &ctx->tx_list);
532	atomic_inc(&ctx->encrypt_pending);
533
534	rc = crypto_aead_encrypt(aead_req);
535	if (!rc || rc != -EINPROGRESS) {
536		atomic_dec(&ctx->encrypt_pending);
537		sge->offset -= prot->prepend_size;
538		sge->length += prot->prepend_size;
539	}
540
541	if (!rc) {
542		WRITE_ONCE(rec->tx_ready, true);
543	} else if (rc != -EINPROGRESS) {
544		list_del(&rec->list);
545		return rc;
546	}
547
548	/* Unhook the record from context if encryption is not failure */
549	ctx->open_rec = NULL;
550	tls_advance_record_sn(sk, prot, &tls_ctx->tx);
551	return rc;
552}
553
554static int tls_split_open_record(struct sock *sk, struct tls_rec *from,
555				 struct tls_rec **to, struct sk_msg *msg_opl,
556				 struct sk_msg *msg_oen, u32 split_point,
557				 u32 tx_overhead_size, u32 *orig_end)
558{
559	u32 i, j, bytes = 0, apply = msg_opl->apply_bytes;
560	struct scatterlist *sge, *osge, *nsge;
561	u32 orig_size = msg_opl->sg.size;
562	struct scatterlist tmp = { };
563	struct sk_msg *msg_npl;
564	struct tls_rec *new;
565	int ret;
566
567	new = tls_get_rec(sk);
568	if (!new)
569		return -ENOMEM;
570	ret = sk_msg_alloc(sk, &new->msg_encrypted, msg_opl->sg.size +
571			   tx_overhead_size, 0);
572	if (ret < 0) {
573		tls_free_rec(sk, new);
574		return ret;
575	}
576
577	*orig_end = msg_opl->sg.end;
578	i = msg_opl->sg.start;
579	sge = sk_msg_elem(msg_opl, i);
580	while (apply && sge->length) {
581		if (sge->length > apply) {
582			u32 len = sge->length - apply;
583
584			get_page(sg_page(sge));
585			sg_set_page(&tmp, sg_page(sge), len,
586				    sge->offset + apply);
587			sge->length = apply;
588			bytes += apply;
589			apply = 0;
590		} else {
591			apply -= sge->length;
592			bytes += sge->length;
593		}
594
595		sk_msg_iter_var_next(i);
596		if (i == msg_opl->sg.end)
597			break;
598		sge = sk_msg_elem(msg_opl, i);
599	}
600
601	msg_opl->sg.end = i;
602	msg_opl->sg.curr = i;
603	msg_opl->sg.copybreak = 0;
604	msg_opl->apply_bytes = 0;
605	msg_opl->sg.size = bytes;
606
607	msg_npl = &new->msg_plaintext;
608	msg_npl->apply_bytes = apply;
609	msg_npl->sg.size = orig_size - bytes;
610
611	j = msg_npl->sg.start;
612	nsge = sk_msg_elem(msg_npl, j);
613	if (tmp.length) {
614		memcpy(nsge, &tmp, sizeof(*nsge));
615		sk_msg_iter_var_next(j);
616		nsge = sk_msg_elem(msg_npl, j);
617	}
618
619	osge = sk_msg_elem(msg_opl, i);
620	while (osge->length) {
621		memcpy(nsge, osge, sizeof(*nsge));
622		sg_unmark_end(nsge);
623		sk_msg_iter_var_next(i);
624		sk_msg_iter_var_next(j);
625		if (i == *orig_end)
626			break;
627		osge = sk_msg_elem(msg_opl, i);
628		nsge = sk_msg_elem(msg_npl, j);
629	}
630
631	msg_npl->sg.end = j;
632	msg_npl->sg.curr = j;
633	msg_npl->sg.copybreak = 0;
634
635	*to = new;
636	return 0;
637}
638
639static void tls_merge_open_record(struct sock *sk, struct tls_rec *to,
640				  struct tls_rec *from, u32 orig_end)
641{
642	struct sk_msg *msg_npl = &from->msg_plaintext;
643	struct sk_msg *msg_opl = &to->msg_plaintext;
644	struct scatterlist *osge, *nsge;
645	u32 i, j;
646
647	i = msg_opl->sg.end;
648	sk_msg_iter_var_prev(i);
649	j = msg_npl->sg.start;
650
651	osge = sk_msg_elem(msg_opl, i);
652	nsge = sk_msg_elem(msg_npl, j);
653
654	if (sg_page(osge) == sg_page(nsge) &&
655	    osge->offset + osge->length == nsge->offset) {
656		osge->length += nsge->length;
657		put_page(sg_page(nsge));
658	}
659
660	msg_opl->sg.end = orig_end;
661	msg_opl->sg.curr = orig_end;
662	msg_opl->sg.copybreak = 0;
663	msg_opl->apply_bytes = msg_opl->sg.size + msg_npl->sg.size;
664	msg_opl->sg.size += msg_npl->sg.size;
665
666	sk_msg_free(sk, &to->msg_encrypted);
667	sk_msg_xfer_full(&to->msg_encrypted, &from->msg_encrypted);
668
669	kfree(from);
670}
671
672static int tls_push_record(struct sock *sk, int flags,
673			   unsigned char record_type)
674{
675	struct tls_context *tls_ctx = tls_get_ctx(sk);
676	struct tls_prot_info *prot = &tls_ctx->prot_info;
677	struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
678	struct tls_rec *rec = ctx->open_rec, *tmp = NULL;
679	u32 i, split_point, orig_end;
680	struct sk_msg *msg_pl, *msg_en;
681	struct aead_request *req;
682	bool split;
683	int rc;
684
685	if (!rec)
686		return 0;
687
688	msg_pl = &rec->msg_plaintext;
689	msg_en = &rec->msg_encrypted;
690
691	split_point = msg_pl->apply_bytes;
692	split = split_point && split_point < msg_pl->sg.size;
693	if (unlikely((!split &&
694		      msg_pl->sg.size +
695		      prot->overhead_size > msg_en->sg.size) ||
696		     (split &&
697		      split_point +
698		      prot->overhead_size > msg_en->sg.size))) {
699		split = true;
700		split_point = msg_en->sg.size;
701	}
702	if (split) {
703		rc = tls_split_open_record(sk, rec, &tmp, msg_pl, msg_en,
704					   split_point, prot->overhead_size,
705					   &orig_end);
706		if (rc < 0)
707			return rc;
708		/* This can happen if above tls_split_open_record allocates
709		 * a single large encryption buffer instead of two smaller
710		 * ones. In this case adjust pointers and continue without
711		 * split.
712		 */
713		if (!msg_pl->sg.size) {
714			tls_merge_open_record(sk, rec, tmp, orig_end);
715			msg_pl = &rec->msg_plaintext;
716			msg_en = &rec->msg_encrypted;
717			split = false;
718		}
719		sk_msg_trim(sk, msg_en, msg_pl->sg.size +
720			    prot->overhead_size);
721	}
722
723	rec->tx_flags = flags;
724	req = &rec->aead_req;
725
726	i = msg_pl->sg.end;
727	sk_msg_iter_var_prev(i);
728
729	rec->content_type = record_type;
730	if (prot->version == TLS_1_3_VERSION) {
731		/* Add content type to end of message.  No padding added */
732		sg_set_buf(&rec->sg_content_type, &rec->content_type, 1);
733		sg_mark_end(&rec->sg_content_type);
734		sg_chain(msg_pl->sg.data, msg_pl->sg.end + 1,
735			 &rec->sg_content_type);
736	} else {
737		sg_mark_end(sk_msg_elem(msg_pl, i));
738	}
739
740	if (msg_pl->sg.end < msg_pl->sg.start) {
741		sg_chain(&msg_pl->sg.data[msg_pl->sg.start],
742			 MAX_SKB_FRAGS - msg_pl->sg.start + 1,
743			 msg_pl->sg.data);
744	}
745
746	i = msg_pl->sg.start;
747	sg_chain(rec->sg_aead_in, 2, &msg_pl->sg.data[i]);
748
749	i = msg_en->sg.end;
750	sk_msg_iter_var_prev(i);
751	sg_mark_end(sk_msg_elem(msg_en, i));
752
753	i = msg_en->sg.start;
754	sg_chain(rec->sg_aead_out, 2, &msg_en->sg.data[i]);
755
756	tls_make_aad(rec->aad_space, msg_pl->sg.size + prot->tail_size,
757		     tls_ctx->tx.rec_seq, prot->rec_seq_size,
758		     record_type, prot->version);
759
760	tls_fill_prepend(tls_ctx,
761			 page_address(sg_page(&msg_en->sg.data[i])) +
762			 msg_en->sg.data[i].offset,
763			 msg_pl->sg.size + prot->tail_size,
764			 record_type, prot->version);
765
766	tls_ctx->pending_open_record_frags = false;
767
768	rc = tls_do_encryption(sk, tls_ctx, ctx, req,
769			       msg_pl->sg.size + prot->tail_size, i);
770	if (rc < 0) {
771		if (rc != -EINPROGRESS) {
772			tls_err_abort(sk, -EBADMSG);
773			if (split) {
774				tls_ctx->pending_open_record_frags = true;
775				tls_merge_open_record(sk, rec, tmp, orig_end);
776			}
777		}
778		ctx->async_capable = 1;
779		return rc;
780	} else if (split) {
781		msg_pl = &tmp->msg_plaintext;
782		msg_en = &tmp->msg_encrypted;
783		sk_msg_trim(sk, msg_en, msg_pl->sg.size + prot->overhead_size);
784		tls_ctx->pending_open_record_frags = true;
785		ctx->open_rec = tmp;
786	}
787
788	return tls_tx_records(sk, flags);
789}
790
791static int bpf_exec_tx_verdict(struct sk_msg *msg, struct sock *sk,
792			       bool full_record, u8 record_type,
793			       ssize_t *copied, int flags)
794{
795	struct tls_context *tls_ctx = tls_get_ctx(sk);
796	struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
797	struct sk_msg msg_redir = { };
798	struct sk_psock *psock;
799	struct sock *sk_redir;
800	struct tls_rec *rec;
801	bool enospc, policy;
802	int err = 0, send;
803	u32 delta = 0;
804
805	policy = !(flags & MSG_SENDPAGE_NOPOLICY);
806	psock = sk_psock_get(sk);
807	if (!psock || !policy) {
808		err = tls_push_record(sk, flags, record_type);
809		if (err && err != -EINPROGRESS && sk->sk_err == EBADMSG) {
810			*copied -= sk_msg_free(sk, msg);
811			tls_free_open_rec(sk);
812			err = -sk->sk_err;
813		}
814		if (psock)
815			sk_psock_put(sk, psock);
816		return err;
817	}
818more_data:
819	enospc = sk_msg_full(msg);
820	if (psock->eval == __SK_NONE) {
821		delta = msg->sg.size;
822		psock->eval = sk_psock_msg_verdict(sk, psock, msg);
823		delta -= msg->sg.size;
824	}
825	if (msg->cork_bytes && msg->cork_bytes > msg->sg.size &&
826	    !enospc && !full_record) {
827		err = -ENOSPC;
828		goto out_err;
829	}
830	msg->cork_bytes = 0;
831	send = msg->sg.size;
832	if (msg->apply_bytes && msg->apply_bytes < send)
833		send = msg->apply_bytes;
834
835	switch (psock->eval) {
836	case __SK_PASS:
837		err = tls_push_record(sk, flags, record_type);
838		if (err && err != -EINPROGRESS && sk->sk_err == EBADMSG) {
839			*copied -= sk_msg_free(sk, msg);
840			tls_free_open_rec(sk);
841			err = -sk->sk_err;
842			goto out_err;
843		}
844		break;
845	case __SK_REDIRECT:
846		sk_redir = psock->sk_redir;
847		memcpy(&msg_redir, msg, sizeof(*msg));
848		if (msg->apply_bytes < send)
849			msg->apply_bytes = 0;
850		else
851			msg->apply_bytes -= send;
852		sk_msg_return_zero(sk, msg, send);
853		msg->sg.size -= send;
854		release_sock(sk);
855		err = tcp_bpf_sendmsg_redir(sk_redir, &msg_redir, send, flags);
856		lock_sock(sk);
857		if (err < 0) {
858			*copied -= sk_msg_free_nocharge(sk, &msg_redir);
859			msg->sg.size = 0;
860		}
861		if (msg->sg.size == 0)
862			tls_free_open_rec(sk);
863		break;
864	case __SK_DROP:
865	default:
866		sk_msg_free_partial(sk, msg, send);
867		if (msg->apply_bytes < send)
868			msg->apply_bytes = 0;
869		else
870			msg->apply_bytes -= send;
871		if (msg->sg.size == 0)
872			tls_free_open_rec(sk);
873		*copied -= (send + delta);
874		err = -EACCES;
875	}
876
877	if (likely(!err)) {
878		bool reset_eval = !ctx->open_rec;
879
880		rec = ctx->open_rec;
881		if (rec) {
882			msg = &rec->msg_plaintext;
883			if (!msg->apply_bytes)
884				reset_eval = true;
885		}
886		if (reset_eval) {
887			psock->eval = __SK_NONE;
888			if (psock->sk_redir) {
889				sock_put(psock->sk_redir);
890				psock->sk_redir = NULL;
891			}
892		}
893		if (rec)
894			goto more_data;
895	}
896 out_err:
897	sk_psock_put(sk, psock);
898	return err;
899}
900
901static int tls_sw_push_pending_record(struct sock *sk, int flags)
902{
903	struct tls_context *tls_ctx = tls_get_ctx(sk);
904	struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
905	struct tls_rec *rec = ctx->open_rec;
906	struct sk_msg *msg_pl;
907	size_t copied;
908
909	if (!rec)
910		return 0;
911
912	msg_pl = &rec->msg_plaintext;
913	copied = msg_pl->sg.size;
914	if (!copied)
915		return 0;
916
917	return bpf_exec_tx_verdict(msg_pl, sk, true, TLS_RECORD_TYPE_DATA,
918				   &copied, flags);
919}
920
921int tls_sw_sendmsg(struct sock *sk, struct msghdr *msg, size_t size)
922{
923	long timeo = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT);
924	struct tls_context *tls_ctx = tls_get_ctx(sk);
925	struct tls_prot_info *prot = &tls_ctx->prot_info;
926	struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
927	bool async_capable = ctx->async_capable;
928	unsigned char record_type = TLS_RECORD_TYPE_DATA;
929	bool is_kvec = iov_iter_is_kvec(&msg->msg_iter);
930	bool eor = !(msg->msg_flags & MSG_MORE);
931	size_t try_to_copy;
932	ssize_t copied = 0;
933	struct sk_msg *msg_pl, *msg_en;
934	struct tls_rec *rec;
935	int required_size;
936	int num_async = 0;
937	bool full_record;
938	int record_room;
939	int num_zc = 0;
940	int orig_size;
941	int ret = 0;
942	int pending;
943
944	if (msg->msg_flags & ~(MSG_MORE | MSG_DONTWAIT | MSG_NOSIGNAL |
945			       MSG_CMSG_COMPAT))
946		return -EOPNOTSUPP;
947
948	ret = mutex_lock_interruptible(&tls_ctx->tx_lock);
949	if (ret)
950		return ret;
951	lock_sock(sk);
952
953	if (unlikely(msg->msg_controllen)) {
954		ret = tls_proccess_cmsg(sk, msg, &record_type);
955		if (ret) {
956			if (ret == -EINPROGRESS)
957				num_async++;
958			else if (ret != -EAGAIN)
959				goto send_end;
960		}
961	}
962
963	while (msg_data_left(msg)) {
964		if (sk->sk_err) {
965			ret = -sk->sk_err;
966			goto send_end;
967		}
968
969		if (ctx->open_rec)
970			rec = ctx->open_rec;
971		else
972			rec = ctx->open_rec = tls_get_rec(sk);
973		if (!rec) {
974			ret = -ENOMEM;
975			goto send_end;
976		}
977
978		msg_pl = &rec->msg_plaintext;
979		msg_en = &rec->msg_encrypted;
980
981		orig_size = msg_pl->sg.size;
982		full_record = false;
983		try_to_copy = msg_data_left(msg);
984		record_room = TLS_MAX_PAYLOAD_SIZE - msg_pl->sg.size;
985		if (try_to_copy >= record_room) {
986			try_to_copy = record_room;
987			full_record = true;
988		}
989
990		required_size = msg_pl->sg.size + try_to_copy +
991				prot->overhead_size;
992
993		if (!sk_stream_memory_free(sk))
994			goto wait_for_sndbuf;
995
996alloc_encrypted:
997		ret = tls_alloc_encrypted_msg(sk, required_size);
998		if (ret) {
999			if (ret != -ENOSPC)
1000				goto wait_for_memory;
1001
1002			/* Adjust try_to_copy according to the amount that was
1003			 * actually allocated. The difference is due
1004			 * to max sg elements limit
1005			 */
1006			try_to_copy -= required_size - msg_en->sg.size;
1007			full_record = true;
1008		}
1009
1010		if (!is_kvec && (full_record || eor) && !async_capable) {
1011			u32 first = msg_pl->sg.end;
1012
1013			ret = sk_msg_zerocopy_from_iter(sk, &msg->msg_iter,
1014							msg_pl, try_to_copy);
1015			if (ret)
1016				goto fallback_to_reg_send;
1017
1018			num_zc++;
1019			copied += try_to_copy;
1020
1021			sk_msg_sg_copy_set(msg_pl, first);
1022			ret = bpf_exec_tx_verdict(msg_pl, sk, full_record,
1023						  record_type, &copied,
1024						  msg->msg_flags);
1025			if (ret) {
1026				if (ret == -EINPROGRESS)
1027					num_async++;
1028				else if (ret == -ENOMEM)
1029					goto wait_for_memory;
1030				else if (ctx->open_rec && ret == -ENOSPC)
1031					goto rollback_iter;
1032				else if (ret != -EAGAIN)
1033					goto send_end;
1034			}
1035			continue;
1036rollback_iter:
1037			copied -= try_to_copy;
1038			sk_msg_sg_copy_clear(msg_pl, first);
1039			iov_iter_revert(&msg->msg_iter,
1040					msg_pl->sg.size - orig_size);
1041fallback_to_reg_send:
1042			sk_msg_trim(sk, msg_pl, orig_size);
1043		}
1044
1045		required_size = msg_pl->sg.size + try_to_copy;
1046
1047		ret = tls_clone_plaintext_msg(sk, required_size);
1048		if (ret) {
1049			if (ret != -ENOSPC)
1050				goto send_end;
1051
1052			/* Adjust try_to_copy according to the amount that was
1053			 * actually allocated. The difference is due
1054			 * to max sg elements limit
1055			 */
1056			try_to_copy -= required_size - msg_pl->sg.size;
1057			full_record = true;
1058			sk_msg_trim(sk, msg_en,
1059				    msg_pl->sg.size + prot->overhead_size);
1060		}
1061
1062		if (try_to_copy) {
1063			ret = sk_msg_memcopy_from_iter(sk, &msg->msg_iter,
1064						       msg_pl, try_to_copy);
1065			if (ret < 0)
1066				goto trim_sgl;
1067		}
1068
1069		/* Open records defined only if successfully copied, otherwise
1070		 * we would trim the sg but not reset the open record frags.
1071		 */
1072		tls_ctx->pending_open_record_frags = true;
1073		copied += try_to_copy;
1074		if (full_record || eor) {
1075			ret = bpf_exec_tx_verdict(msg_pl, sk, full_record,
1076						  record_type, &copied,
1077						  msg->msg_flags);
1078			if (ret) {
1079				if (ret == -EINPROGRESS)
1080					num_async++;
1081				else if (ret == -ENOMEM)
1082					goto wait_for_memory;
1083				else if (ret != -EAGAIN) {
1084					if (ret == -ENOSPC)
1085						ret = 0;
1086					goto send_end;
1087				}
1088			}
1089		}
1090
1091		continue;
1092
1093wait_for_sndbuf:
1094		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1095wait_for_memory:
1096		ret = sk_stream_wait_memory(sk, &timeo);
1097		if (ret) {
1098trim_sgl:
1099			if (ctx->open_rec)
1100				tls_trim_both_msgs(sk, orig_size);
1101			goto send_end;
1102		}
1103
1104		if (ctx->open_rec && msg_en->sg.size < required_size)
1105			goto alloc_encrypted;
1106	}
1107
1108	if (!num_async) {
1109		goto send_end;
1110	} else if (num_zc) {
1111		/* Wait for pending encryptions to get completed */
1112		spin_lock_bh(&ctx->encrypt_compl_lock);
1113		ctx->async_notify = true;
1114
1115		pending = atomic_read(&ctx->encrypt_pending);
1116		spin_unlock_bh(&ctx->encrypt_compl_lock);
1117		if (pending)
1118			crypto_wait_req(-EINPROGRESS, &ctx->async_wait);
1119		else
1120			reinit_completion(&ctx->async_wait.completion);
1121
1122		/* There can be no concurrent accesses, since we have no
1123		 * pending encrypt operations
1124		 */
1125		WRITE_ONCE(ctx->async_notify, false);
1126
1127		if (ctx->async_wait.err) {
1128			ret = ctx->async_wait.err;
1129			copied = 0;
1130		}
1131	}
1132
1133	/* Transmit if any encryptions have completed */
1134	if (test_and_clear_bit(BIT_TX_SCHEDULED, &ctx->tx_bitmask)) {
1135		cancel_delayed_work(&ctx->tx_work.work);
1136		tls_tx_records(sk, msg->msg_flags);
1137	}
1138
1139send_end:
1140	ret = sk_stream_error(sk, msg->msg_flags, ret);
1141
1142	release_sock(sk);
1143	mutex_unlock(&tls_ctx->tx_lock);
1144	return copied > 0 ? copied : ret;
1145}
1146
1147static int tls_sw_do_sendpage(struct sock *sk, struct page *page,
1148			      int offset, size_t size, int flags)
1149{
1150	long timeo = sock_sndtimeo(sk, flags & MSG_DONTWAIT);
1151	struct tls_context *tls_ctx = tls_get_ctx(sk);
1152	struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
1153	struct tls_prot_info *prot = &tls_ctx->prot_info;
1154	unsigned char record_type = TLS_RECORD_TYPE_DATA;
1155	struct sk_msg *msg_pl;
1156	struct tls_rec *rec;
1157	int num_async = 0;
1158	ssize_t copied = 0;
1159	bool full_record;
1160	int record_room;
1161	int ret = 0;
1162	bool eor;
1163
1164	eor = !(flags & MSG_SENDPAGE_NOTLAST);
1165	sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);
1166
1167	/* Call the sk_stream functions to manage the sndbuf mem. */
1168	while (size > 0) {
1169		size_t copy, required_size;
1170
1171		if (sk->sk_err) {
1172			ret = -sk->sk_err;
1173			goto sendpage_end;
1174		}
1175
1176		if (ctx->open_rec)
1177			rec = ctx->open_rec;
1178		else
1179			rec = ctx->open_rec = tls_get_rec(sk);
1180		if (!rec) {
1181			ret = -ENOMEM;
1182			goto sendpage_end;
1183		}
1184
1185		msg_pl = &rec->msg_plaintext;
1186
1187		full_record = false;
1188		record_room = TLS_MAX_PAYLOAD_SIZE - msg_pl->sg.size;
1189		copy = size;
1190		if (copy >= record_room) {
1191			copy = record_room;
1192			full_record = true;
1193		}
1194
1195		required_size = msg_pl->sg.size + copy + prot->overhead_size;
1196
1197		if (!sk_stream_memory_free(sk))
1198			goto wait_for_sndbuf;
1199alloc_payload:
1200		ret = tls_alloc_encrypted_msg(sk, required_size);
1201		if (ret) {
1202			if (ret != -ENOSPC)
1203				goto wait_for_memory;
1204
1205			/* Adjust copy according to the amount that was
1206			 * actually allocated. The difference is due
1207			 * to max sg elements limit
1208			 */
1209			copy -= required_size - msg_pl->sg.size;
1210			full_record = true;
1211		}
1212
1213		sk_msg_page_add(msg_pl, page, copy, offset);
1214		msg_pl->sg.copybreak = 0;
1215		msg_pl->sg.curr = msg_pl->sg.end;
1216		sk_mem_charge(sk, copy);
1217
1218		offset += copy;
1219		size -= copy;
1220		copied += copy;
1221
1222		tls_ctx->pending_open_record_frags = true;
1223		if (full_record || eor || sk_msg_full(msg_pl)) {
1224			ret = bpf_exec_tx_verdict(msg_pl, sk, full_record,
1225						  record_type, &copied, flags);
1226			if (ret) {
1227				if (ret == -EINPROGRESS)
1228					num_async++;
1229				else if (ret == -ENOMEM)
1230					goto wait_for_memory;
1231				else if (ret != -EAGAIN) {
1232					if (ret == -ENOSPC)
1233						ret = 0;
1234					goto sendpage_end;
1235				}
1236			}
1237		}
1238		continue;
1239wait_for_sndbuf:
1240		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1241wait_for_memory:
1242		ret = sk_stream_wait_memory(sk, &timeo);
1243		if (ret) {
1244			if (ctx->open_rec)
1245				tls_trim_both_msgs(sk, msg_pl->sg.size);
1246			goto sendpage_end;
1247		}
1248
1249		if (ctx->open_rec)
1250			goto alloc_payload;
1251	}
1252
1253	if (num_async) {
1254		/* Transmit if any encryptions have completed */
1255		if (test_and_clear_bit(BIT_TX_SCHEDULED, &ctx->tx_bitmask)) {
1256			cancel_delayed_work(&ctx->tx_work.work);
1257			tls_tx_records(sk, flags);
1258		}
1259	}
1260sendpage_end:
1261	ret = sk_stream_error(sk, flags, ret);
1262	return copied > 0 ? copied : ret;
1263}
1264
1265int tls_sw_sendpage_locked(struct sock *sk, struct page *page,
1266			   int offset, size_t size, int flags)
1267{
1268	if (flags & ~(MSG_MORE | MSG_DONTWAIT | MSG_NOSIGNAL |
1269		      MSG_SENDPAGE_NOTLAST | MSG_SENDPAGE_NOPOLICY |
1270		      MSG_NO_SHARED_FRAGS))
1271		return -EOPNOTSUPP;
1272
1273	return tls_sw_do_sendpage(sk, page, offset, size, flags);
1274}
1275
1276int tls_sw_sendpage(struct sock *sk, struct page *page,
1277		    int offset, size_t size, int flags)
1278{
1279	struct tls_context *tls_ctx = tls_get_ctx(sk);
1280	int ret;
1281
1282	if (flags & ~(MSG_MORE | MSG_DONTWAIT | MSG_NOSIGNAL |
1283		      MSG_SENDPAGE_NOTLAST | MSG_SENDPAGE_NOPOLICY))
1284		return -EOPNOTSUPP;
1285
1286	ret = mutex_lock_interruptible(&tls_ctx->tx_lock);
1287	if (ret)
1288		return ret;
1289	lock_sock(sk);
1290	ret = tls_sw_do_sendpage(sk, page, offset, size, flags);
1291	release_sock(sk);
1292	mutex_unlock(&tls_ctx->tx_lock);
1293	return ret;
1294}
1295
1296static struct sk_buff *tls_wait_data(struct sock *sk, struct sk_psock *psock,
1297				     bool nonblock, long timeo, int *err)
1298{
1299	struct tls_context *tls_ctx = tls_get_ctx(sk);
1300	struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
1301	struct sk_buff *skb;
1302	DEFINE_WAIT_FUNC(wait, woken_wake_function);
1303
1304	while (!(skb = ctx->recv_pkt) && sk_psock_queue_empty(psock)) {
1305		if (sk->sk_err) {
1306			*err = sock_error(sk);
1307			return NULL;
1308		}
1309
1310		if (!skb_queue_empty(&sk->sk_receive_queue)) {
1311			__strp_unpause(&ctx->strp);
1312			if (ctx->recv_pkt)
1313				return ctx->recv_pkt;
1314		}
1315
1316		if (sk->sk_shutdown & RCV_SHUTDOWN)
1317			return NULL;
1318
1319		if (sock_flag(sk, SOCK_DONE))
1320			return NULL;
1321
1322		if (nonblock || !timeo) {
1323			*err = -EAGAIN;
1324			return NULL;
1325		}
1326
1327		add_wait_queue(sk_sleep(sk), &wait);
1328		sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk);
1329		sk_wait_event(sk, &timeo,
1330			      ctx->recv_pkt != skb ||
1331			      !sk_psock_queue_empty(psock),
1332			      &wait);
1333		sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk);
1334		remove_wait_queue(sk_sleep(sk), &wait);
1335
1336		/* Handle signals */
1337		if (signal_pending(current)) {
1338			*err = sock_intr_errno(timeo);
1339			return NULL;
1340		}
1341	}
1342
1343	return skb;
1344}
1345
1346static int tls_setup_from_iter(struct sock *sk, struct iov_iter *from,
1347			       int length, int *pages_used,
1348			       unsigned int *size_used,
1349			       struct scatterlist *to,
1350			       int to_max_pages)
1351{
1352	int rc = 0, i = 0, num_elem = *pages_used, maxpages;
1353	struct page *pages[MAX_SKB_FRAGS];
1354	unsigned int size = *size_used;
1355	ssize_t copied, use;
1356	size_t offset;
1357
1358	while (length > 0) {
1359		i = 0;
1360		maxpages = to_max_pages - num_elem;
1361		if (maxpages == 0) {
1362			rc = -EFAULT;
1363			goto out;
1364		}
1365		copied = iov_iter_get_pages(from, pages,
1366					    length,
1367					    maxpages, &offset);
1368		if (copied <= 0) {
1369			rc = -EFAULT;
1370			goto out;
1371		}
1372
1373		iov_iter_advance(from, copied);
1374
1375		length -= copied;
1376		size += copied;
1377		while (copied) {
1378			use = min_t(int, copied, PAGE_SIZE - offset);
1379
1380			sg_set_page(&to[num_elem],
1381				    pages[i], use, offset);
1382			sg_unmark_end(&to[num_elem]);
1383			/* We do not uncharge memory from this API */
1384
1385			offset = 0;
1386			copied -= use;
1387
1388			i++;
1389			num_elem++;
1390		}
1391	}
1392	/* Mark the end in the last sg entry if newly added */
1393	if (num_elem > *pages_used)
1394		sg_mark_end(&to[num_elem - 1]);
1395out:
1396	if (rc)
1397		iov_iter_revert(from, size - *size_used);
1398	*size_used = size;
1399	*pages_used = num_elem;
1400
1401	return rc;
1402}
1403
1404/* This function decrypts the input skb into either out_iov or in out_sg
1405 * or in skb buffers itself. The input parameter 'zc' indicates if
1406 * zero-copy mode needs to be tried or not. With zero-copy mode, either
1407 * out_iov or out_sg must be non-NULL. In case both out_iov and out_sg are
1408 * NULL, then the decryption happens inside skb buffers itself, i.e.
1409 * zero-copy gets disabled and 'zc' is updated.
1410 */
1411
1412static int decrypt_internal(struct sock *sk, struct sk_buff *skb,
1413			    struct iov_iter *out_iov,
1414			    struct scatterlist *out_sg,
1415			    int *chunk, bool *zc, bool async)
1416{
1417	struct tls_context *tls_ctx = tls_get_ctx(sk);
1418	struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
1419	struct tls_prot_info *prot = &tls_ctx->prot_info;
1420	struct strp_msg *rxm = strp_msg(skb);
1421	int n_sgin, n_sgout, nsg, mem_size, aead_size, err, pages = 0;
1422	struct aead_request *aead_req;
1423	struct sk_buff *unused;
1424	u8 *aad, *iv, *mem = NULL;
1425	struct scatterlist *sgin = NULL;
1426	struct scatterlist *sgout = NULL;
1427	const int data_len = rxm->full_len - prot->overhead_size +
1428			     prot->tail_size;
1429	int iv_offset = 0;
1430
1431	if (*zc && (out_iov || out_sg)) {
1432		if (out_iov)
1433			n_sgout = iov_iter_npages(out_iov, INT_MAX) + 1;
1434		else
1435			n_sgout = sg_nents(out_sg);
1436		n_sgin = skb_nsg(skb, rxm->offset + prot->prepend_size,
1437				 rxm->full_len - prot->prepend_size);
1438	} else {
1439		n_sgout = 0;
1440		*zc = false;
1441		n_sgin = skb_cow_data(skb, 0, &unused);
1442	}
1443
1444	if (n_sgin < 1)
1445		return -EBADMSG;
1446
1447	/* Increment to accommodate AAD */
1448	n_sgin = n_sgin + 1;
1449
1450	nsg = n_sgin + n_sgout;
1451
1452	aead_size = sizeof(*aead_req) + crypto_aead_reqsize(ctx->aead_recv);
1453	mem_size = aead_size + (nsg * sizeof(struct scatterlist));
1454	mem_size = mem_size + prot->aad_size;
1455	mem_size = mem_size + crypto_aead_ivsize(ctx->aead_recv);
1456
1457	/* Allocate a single block of memory which contains
1458	 * aead_req || sgin[] || sgout[] || aad || iv.
1459	 * This order achieves correct alignment for aead_req, sgin, sgout.
1460	 */
1461	mem = kmalloc(mem_size, sk->sk_allocation);
1462	if (!mem)
1463		return -ENOMEM;
1464
1465	/* Segment the allocated memory */
1466	aead_req = (struct aead_request *)mem;
1467	sgin = (struct scatterlist *)(mem + aead_size);
1468	sgout = sgin + n_sgin;
1469	aad = (u8 *)(sgout + n_sgout);
1470	iv = aad + prot->aad_size;
1471
1472	/* For CCM based ciphers, first byte of nonce+iv is always '2' */
1473	if (prot->cipher_type == TLS_CIPHER_AES_CCM_128) {
1474		iv[0] = 2;
1475		iv_offset = 1;
1476	}
1477
1478	/* Prepare IV */
1479	err = skb_copy_bits(skb, rxm->offset + TLS_HEADER_SIZE,
1480			    iv + iv_offset + prot->salt_size,
1481			    prot->iv_size);
1482	if (err < 0) {
1483		kfree(mem);
1484		return err;
1485	}
1486	if (prot->version == TLS_1_3_VERSION)
1487		memcpy(iv + iv_offset, tls_ctx->rx.iv,
1488		       prot->iv_size + prot->salt_size);
1489	else
1490		memcpy(iv + iv_offset, tls_ctx->rx.iv, prot->salt_size);
1491
1492	xor_iv_with_seq(prot->version, iv + iv_offset, tls_ctx->rx.rec_seq);
1493
1494	/* Prepare AAD */
1495	tls_make_aad(aad, rxm->full_len - prot->overhead_size +
1496		     prot->tail_size,
1497		     tls_ctx->rx.rec_seq, prot->rec_seq_size,
1498		     ctx->control, prot->version);
1499
1500	/* Prepare sgin */
1501	sg_init_table(sgin, n_sgin);
1502	sg_set_buf(&sgin[0], aad, prot->aad_size);
1503	err = skb_to_sgvec(skb, &sgin[1],
1504			   rxm->offset + prot->prepend_size,
1505			   rxm->full_len - prot->prepend_size);
1506	if (err < 0) {
1507		kfree(mem);
1508		return err;
1509	}
1510
1511	if (n_sgout) {
1512		if (out_iov) {
1513			sg_init_table(sgout, n_sgout);
1514			sg_set_buf(&sgout[0], aad, prot->aad_size);
1515
1516			*chunk = 0;
1517			err = tls_setup_from_iter(sk, out_iov, data_len,
1518						  &pages, chunk, &sgout[1],
1519						  (n_sgout - 1));
1520			if (err < 0)
1521				goto fallback_to_reg_recv;
1522		} else if (out_sg) {
1523			memcpy(sgout, out_sg, n_sgout * sizeof(*sgout));
1524		} else {
1525			goto fallback_to_reg_recv;
1526		}
1527	} else {
1528fallback_to_reg_recv:
1529		sgout = sgin;
1530		pages = 0;
1531		*chunk = data_len;
1532		*zc = false;
1533	}
1534
1535	/* Prepare and submit AEAD request */
1536	err = tls_do_decryption(sk, skb, sgin, sgout, iv,
1537				data_len, aead_req, async);
1538	if (err == -EINPROGRESS)
1539		return err;
1540
1541	/* Release the pages in case iov was mapped to pages */
1542	for (; pages > 0; pages--)
1543		put_page(sg_page(&sgout[pages]));
1544
1545	kfree(mem);
1546	return err;
1547}
1548
1549static int decrypt_skb_update(struct sock *sk, struct sk_buff *skb,
1550			      struct iov_iter *dest, int *chunk, bool *zc,
1551			      bool async)
1552{
1553	struct tls_context *tls_ctx = tls_get_ctx(sk);
1554	struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
1555	struct tls_prot_info *prot = &tls_ctx->prot_info;
1556	struct strp_msg *rxm = strp_msg(skb);
1557	int pad, err = 0;
1558
1559	if (!ctx->decrypted) {
1560		if (tls_ctx->rx_conf == TLS_HW) {
1561			err = tls_device_decrypted(sk, tls_ctx, skb, rxm);
1562			if (err < 0)
1563				return err;
1564		}
1565
1566		/* Still not decrypted after tls_device */
1567		if (!ctx->decrypted) {
1568			err = decrypt_internal(sk, skb, dest, NULL, chunk, zc,
1569					       async);
1570			if (err < 0) {
1571				if (err == -EINPROGRESS)
1572					tls_advance_record_sn(sk, prot,
1573							      &tls_ctx->rx);
1574				else if (err == -EBADMSG)
1575					TLS_INC_STATS(sock_net(sk),
1576						      LINUX_MIB_TLSDECRYPTERROR);
1577				return err;
1578			}
1579		} else {
1580			*zc = false;
1581		}
1582
1583		pad = padding_length(ctx, prot, skb);
1584		if (pad < 0)
1585			return pad;
1586
1587		rxm->full_len -= pad;
1588		rxm->offset += prot->prepend_size;
1589		rxm->full_len -= prot->overhead_size;
1590		tls_advance_record_sn(sk, prot, &tls_ctx->rx);
1591		ctx->decrypted = 1;
1592		ctx->saved_data_ready(sk);
1593	} else {
1594		*zc = false;
1595	}
1596
1597	return err;
1598}
1599
1600int decrypt_skb(struct sock *sk, struct sk_buff *skb,
1601		struct scatterlist *sgout)
1602{
1603	bool zc = true;
1604	int chunk;
1605
1606	return decrypt_internal(sk, skb, NULL, sgout, &chunk, &zc, false);
1607}
1608
1609static bool tls_sw_advance_skb(struct sock *sk, struct sk_buff *skb,
1610			       unsigned int len)
1611{
1612	struct tls_context *tls_ctx = tls_get_ctx(sk);
1613	struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
1614
1615	if (skb) {
1616		struct strp_msg *rxm = strp_msg(skb);
1617
1618		if (len < rxm->full_len) {
1619			rxm->offset += len;
1620			rxm->full_len -= len;
1621			return false;
1622		}
1623		consume_skb(skb);
1624	}
1625
1626	/* Finished with message */
1627	ctx->recv_pkt = NULL;
1628	__strp_unpause(&ctx->strp);
1629
1630	return true;
1631}
1632
1633/* This function traverses the rx_list in tls receive context to copies the
1634 * decrypted records into the buffer provided by caller zero copy is not
1635 * true. Further, the records are removed from the rx_list if it is not a peek
1636 * case and the record has been consumed completely.
1637 */
1638static int process_rx_list(struct tls_sw_context_rx *ctx,
1639			   struct msghdr *msg,
1640			   u8 *control,
1641			   bool *cmsg,
1642			   size_t skip,
1643			   size_t len,
1644			   bool zc,
1645			   bool is_peek)
1646{
1647	struct sk_buff *skb = skb_peek(&ctx->rx_list);
1648	u8 ctrl = *control;
1649	u8 msgc = *cmsg;
1650	struct tls_msg *tlm;
1651	ssize_t copied = 0;
1652
1653	/* Set the record type in 'control' if caller didn't pass it */
1654	if (!ctrl && skb) {
1655		tlm = tls_msg(skb);
1656		ctrl = tlm->control;
1657	}
1658
1659	while (skip && skb) {
1660		struct strp_msg *rxm = strp_msg(skb);
1661		tlm = tls_msg(skb);
1662
1663		/* Cannot process a record of different type */
1664		if (ctrl != tlm->control)
1665			return 0;
1666
1667		if (skip < rxm->full_len)
1668			break;
1669
1670		skip = skip - rxm->full_len;
1671		skb = skb_peek_next(skb, &ctx->rx_list);
1672	}
1673
1674	while (len && skb) {
1675		struct sk_buff *next_skb;
1676		struct strp_msg *rxm = strp_msg(skb);
1677		int chunk = min_t(unsigned int, rxm->full_len - skip, len);
1678
1679		tlm = tls_msg(skb);
1680
1681		/* Cannot process a record of different type */
1682		if (ctrl != tlm->control)
1683			return 0;
1684
1685		/* Set record type if not already done. For a non-data record,
1686		 * do not proceed if record type could not be copied.
1687		 */
1688		if (!msgc) {
1689			int cerr = put_cmsg(msg, SOL_TLS, TLS_GET_RECORD_TYPE,
1690					    sizeof(ctrl), &ctrl);
1691			msgc = true;
1692			if (ctrl != TLS_RECORD_TYPE_DATA) {
1693				if (cerr || msg->msg_flags & MSG_CTRUNC)
1694					return -EIO;
1695
1696				*cmsg = msgc;
1697			}
1698		}
1699
1700		if (!zc || (rxm->full_len - skip) > len) {
1701			int err = skb_copy_datagram_msg(skb, rxm->offset + skip,
1702						    msg, chunk);
1703			if (err < 0)
1704				return err;
1705		}
1706
1707		len = len - chunk;
1708		copied = copied + chunk;
1709
1710		/* Consume the data from record if it is non-peek case*/
1711		if (!is_peek) {
1712			rxm->offset = rxm->offset + chunk;
1713			rxm->full_len = rxm->full_len - chunk;
1714
1715			/* Return if there is unconsumed data in the record */
1716			if (rxm->full_len - skip)
1717				break;
1718		}
1719
1720		/* The remaining skip-bytes must lie in 1st record in rx_list.
1721		 * So from the 2nd record, 'skip' should be 0.
1722		 */
1723		skip = 0;
1724
1725		if (msg)
1726			msg->msg_flags |= MSG_EOR;
1727
1728		next_skb = skb_peek_next(skb, &ctx->rx_list);
1729
1730		if (!is_peek) {
1731			skb_unlink(skb, &ctx->rx_list);
1732			consume_skb(skb);
1733		}
1734
1735		skb = next_skb;
1736	}
1737
1738	*control = ctrl;
1739	return copied;
1740}
1741
1742int tls_sw_recvmsg(struct sock *sk,
1743		   struct msghdr *msg,
1744		   size_t len,
1745		   int nonblock,
1746		   int flags,
1747		   int *addr_len)
1748{
1749	struct tls_context *tls_ctx = tls_get_ctx(sk);
1750	struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
1751	struct tls_prot_info *prot = &tls_ctx->prot_info;
1752	struct sk_psock *psock;
1753	unsigned char control = 0;
1754	ssize_t decrypted = 0;
1755	struct strp_msg *rxm;
1756	struct tls_msg *tlm;
1757	struct sk_buff *skb;
1758	ssize_t copied = 0;
1759	bool cmsg = false;
1760	int target, err = 0;
1761	long timeo;
1762	bool is_kvec = iov_iter_is_kvec(&msg->msg_iter);
1763	bool is_peek = flags & MSG_PEEK;
1764	bool bpf_strp_enabled;
1765	int num_async = 0;
1766	int pending;
1767
1768	flags |= nonblock;
1769
1770	if (unlikely(flags & MSG_ERRQUEUE))
1771		return sock_recv_errqueue(sk, msg, len, SOL_IP, IP_RECVERR);
1772
1773	psock = sk_psock_get(sk);
1774	lock_sock(sk);
1775	bpf_strp_enabled = sk_psock_strp_enabled(psock);
1776
1777	/* Process pending decrypted records. It must be non-zero-copy */
1778	err = process_rx_list(ctx, msg, &control, &cmsg, 0, len, false,
1779			      is_peek);
1780	if (err < 0) {
1781		tls_err_abort(sk, err);
1782		goto end;
1783	} else {
1784		copied = err;
1785	}
1786
1787	if (len <= copied)
1788		goto recv_end;
1789
1790	target = sock_rcvlowat(sk, flags & MSG_WAITALL, len);
1791	len = len - copied;
1792	timeo = sock_rcvtimeo(sk, flags & MSG_DONTWAIT);
1793
1794	while (len && (decrypted + copied < target || ctx->recv_pkt)) {
1795		bool retain_skb = false;
1796		bool zc = false;
1797		int to_decrypt;
1798		int chunk = 0;
1799		bool async_capable;
1800		bool async = false;
1801
1802		skb = tls_wait_data(sk, psock, flags & MSG_DONTWAIT, timeo, &err);
1803		if (!skb) {
1804			if (psock) {
1805				int ret = __tcp_bpf_recvmsg(sk, psock,
1806							    msg, len, flags);
1807
1808				if (ret > 0) {
1809					decrypted += ret;
1810					len -= ret;
1811					continue;
1812				}
1813			}
1814			goto recv_end;
1815		} else {
1816			tlm = tls_msg(skb);
1817			if (prot->version == TLS_1_3_VERSION)
1818				tlm->control = 0;
1819			else
1820				tlm->control = ctx->control;
1821		}
1822
1823		rxm = strp_msg(skb);
1824
1825		to_decrypt = rxm->full_len - prot->overhead_size;
1826
1827		if (to_decrypt <= len && !is_kvec && !is_peek &&
1828		    ctx->control == TLS_RECORD_TYPE_DATA &&
1829		    prot->version != TLS_1_3_VERSION &&
1830		    !bpf_strp_enabled)
1831			zc = true;
1832
1833		/* Do not use async mode if record is non-data */
1834		if (ctx->control == TLS_RECORD_TYPE_DATA && !bpf_strp_enabled)
1835			async_capable = ctx->async_capable;
1836		else
1837			async_capable = false;
1838
1839		err = decrypt_skb_update(sk, skb, &msg->msg_iter,
1840					 &chunk, &zc, async_capable);
1841		if (err < 0 && err != -EINPROGRESS) {
1842			tls_err_abort(sk, -EBADMSG);
1843			goto recv_end;
1844		}
1845
1846		if (err == -EINPROGRESS) {
1847			async = true;
1848			num_async++;
1849		} else if (prot->version == TLS_1_3_VERSION) {
1850			tlm->control = ctx->control;
1851		}
1852
1853		/* If the type of records being processed is not known yet,
1854		 * set it to record type just dequeued. If it is already known,
1855		 * but does not match the record type just dequeued, go to end.
1856		 * We always get record type here since for tls1.2, record type
1857		 * is known just after record is dequeued from stream parser.
1858		 * For tls1.3, we disable async.
1859		 */
1860
1861		if (!control)
1862			control = tlm->control;
1863		else if (control != tlm->control)
1864			goto recv_end;
1865
1866		if (!cmsg) {
1867			int cerr;
1868
1869			cerr = put_cmsg(msg, SOL_TLS, TLS_GET_RECORD_TYPE,
1870					sizeof(control), &control);
1871			cmsg = true;
1872			if (control != TLS_RECORD_TYPE_DATA) {
1873				if (cerr || msg->msg_flags & MSG_CTRUNC) {
1874					err = -EIO;
1875					goto recv_end;
1876				}
1877			}
1878		}
1879
1880		if (async)
1881			goto pick_next_record;
1882
1883		if (!zc) {
1884			if (bpf_strp_enabled) {
1885				err = sk_psock_tls_strp_read(psock, skb);
1886				if (err != __SK_PASS) {
1887					rxm->offset = rxm->offset + rxm->full_len;
1888					rxm->full_len = 0;
1889					if (err == __SK_DROP)
1890						consume_skb(skb);
1891					ctx->recv_pkt = NULL;
1892					__strp_unpause(&ctx->strp);
1893					continue;
1894				}
1895			}
1896
1897			if (rxm->full_len > len) {
1898				retain_skb = true;
1899				chunk = len;
1900			} else {
1901				chunk = rxm->full_len;
1902			}
1903
1904			err = skb_copy_datagram_msg(skb, rxm->offset,
1905						    msg, chunk);
1906			if (err < 0)
1907				goto recv_end;
1908
1909			if (!is_peek) {
1910				rxm->offset = rxm->offset + chunk;
1911				rxm->full_len = rxm->full_len - chunk;
1912			}
1913		}
1914
1915pick_next_record:
1916		if (chunk > len)
1917			chunk = len;
1918
1919		decrypted += chunk;
1920		len -= chunk;
1921
1922		/* For async or peek case, queue the current skb */
1923		if (async || is_peek || retain_skb) {
1924			skb_queue_tail(&ctx->rx_list, skb);
1925			skb = NULL;
1926		}
1927
1928		if (tls_sw_advance_skb(sk, skb, chunk)) {
1929			/* Return full control message to
1930			 * userspace before trying to parse
1931			 * another message type
1932			 */
1933			msg->msg_flags |= MSG_EOR;
1934			if (control != TLS_RECORD_TYPE_DATA)
1935				goto recv_end;
1936		} else {
1937			break;
1938		}
1939	}
1940
1941recv_end:
1942	if (num_async) {
1943		/* Wait for all previously submitted records to be decrypted */
1944		spin_lock_bh(&ctx->decrypt_compl_lock);
1945		ctx->async_notify = true;
1946		pending = atomic_read(&ctx->decrypt_pending);
1947		spin_unlock_bh(&ctx->decrypt_compl_lock);
1948		if (pending) {
1949			err = crypto_wait_req(-EINPROGRESS, &ctx->async_wait);
1950			if (err) {
1951				/* one of async decrypt failed */
1952				tls_err_abort(sk, err);
1953				copied = 0;
1954				decrypted = 0;
1955				goto end;
1956			}
1957		} else {
1958			reinit_completion(&ctx->async_wait.completion);
1959		}
1960
1961		/* There can be no concurrent accesses, since we have no
1962		 * pending decrypt operations
1963		 */
1964		WRITE_ONCE(ctx->async_notify, false);
1965
1966		/* Drain records from the rx_list & copy if required */
1967		if (is_peek || is_kvec)
1968			err = process_rx_list(ctx, msg, &control, &cmsg, copied,
1969					      decrypted, false, is_peek);
1970		else
1971			err = process_rx_list(ctx, msg, &control, &cmsg, 0,
1972					      decrypted, true, is_peek);
1973		if (err < 0) {
1974			tls_err_abort(sk, err);
1975			copied = 0;
1976			goto end;
1977		}
1978	}
1979
1980	copied += decrypted;
1981
1982end:
1983	release_sock(sk);
1984	if (psock)
1985		sk_psock_put(sk, psock);
1986	return copied ? : err;
1987}
1988
1989ssize_t tls_sw_splice_read(struct socket *sock,  loff_t *ppos,
1990			   struct pipe_inode_info *pipe,
1991			   size_t len, unsigned int flags)
1992{
1993	struct tls_context *tls_ctx = tls_get_ctx(sock->sk);
1994	struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
1995	struct strp_msg *rxm = NULL;
1996	struct sock *sk = sock->sk;
1997	struct sk_buff *skb;
1998	ssize_t copied = 0;
1999	int err = 0;
2000	long timeo;
2001	int chunk;
2002	bool zc = false;
2003
2004	lock_sock(sk);
2005
2006	timeo = sock_rcvtimeo(sk, flags & SPLICE_F_NONBLOCK);
2007
2008	skb = tls_wait_data(sk, NULL, flags & SPLICE_F_NONBLOCK, timeo, &err);
2009	if (!skb)
2010		goto splice_read_end;
2011
2012	err = decrypt_skb_update(sk, skb, NULL, &chunk, &zc, false);
2013	if (err < 0) {
2014		tls_err_abort(sk, -EBADMSG);
2015		goto splice_read_end;
2016	}
2017
2018	/* splice does not support reading control messages */
2019	if (ctx->control != TLS_RECORD_TYPE_DATA) {
2020		err = -EINVAL;
2021		goto splice_read_end;
2022	}
2023
2024	rxm = strp_msg(skb);
2025
2026	chunk = min_t(unsigned int, rxm->full_len, len);
2027	copied = skb_splice_bits(skb, sk, rxm->offset, pipe, chunk, flags);
2028	if (copied < 0)
2029		goto splice_read_end;
2030
2031	if (likely(!(flags & MSG_PEEK)))
2032		tls_sw_advance_skb(sk, skb, copied);
2033
2034splice_read_end:
2035	release_sock(sk);
2036	return copied ? : err;
2037}
2038
2039bool tls_sw_stream_read(const struct sock *sk)
2040{
2041	struct tls_context *tls_ctx = tls_get_ctx(sk);
2042	struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
2043	bool ingress_empty = true;
2044	struct sk_psock *psock;
2045
2046	rcu_read_lock();
2047	psock = sk_psock(sk);
2048	if (psock)
2049		ingress_empty = list_empty(&psock->ingress_msg);
2050	rcu_read_unlock();
2051
2052	return !ingress_empty || ctx->recv_pkt ||
2053		!skb_queue_empty(&ctx->rx_list);
2054}
2055
2056static int tls_read_size(struct strparser *strp, struct sk_buff *skb)
2057{
2058	struct tls_context *tls_ctx = tls_get_ctx(strp->sk);
2059	struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
2060	struct tls_prot_info *prot = &tls_ctx->prot_info;
2061	char header[TLS_HEADER_SIZE + MAX_IV_SIZE];
2062	struct strp_msg *rxm = strp_msg(skb);
2063	size_t cipher_overhead;
2064	size_t data_len = 0;
2065	int ret;
2066
2067	/* Verify that we have a full TLS header, or wait for more data */
2068	if (rxm->offset + prot->prepend_size > skb->len)
2069		return 0;
2070
2071	/* Sanity-check size of on-stack buffer. */
2072	if (WARN_ON(prot->prepend_size > sizeof(header))) {
2073		ret = -EINVAL;
2074		goto read_failure;
2075	}
2076
2077	/* Linearize header to local buffer */
2078	ret = skb_copy_bits(skb, rxm->offset, header, prot->prepend_size);
2079
2080	if (ret < 0)
2081		goto read_failure;
2082
2083	ctx->control = header[0];
2084
2085	data_len = ((header[4] & 0xFF) | (header[3] << 8));
2086
2087	cipher_overhead = prot->tag_size;
2088	if (prot->version != TLS_1_3_VERSION)
2089		cipher_overhead += prot->iv_size;
2090
2091	if (data_len > TLS_MAX_PAYLOAD_SIZE + cipher_overhead +
2092	    prot->tail_size) {
2093		ret = -EMSGSIZE;
2094		goto read_failure;
2095	}
2096	if (data_len < cipher_overhead) {
2097		ret = -EBADMSG;
2098		goto read_failure;
2099	}
2100
2101	/* Note that both TLS1.3 and TLS1.2 use TLS_1_2 version here */
2102	if (header[1] != TLS_1_2_VERSION_MINOR ||
2103	    header[2] != TLS_1_2_VERSION_MAJOR) {
2104		ret = -EINVAL;
2105		goto read_failure;
2106	}
2107
2108	tls_device_rx_resync_new_rec(strp->sk, data_len + TLS_HEADER_SIZE,
2109				     TCP_SKB_CB(skb)->seq + rxm->offset);
2110	return data_len + TLS_HEADER_SIZE;
2111
2112read_failure:
2113	tls_err_abort(strp->sk, ret);
2114
2115	return ret;
2116}
2117
2118static void tls_queue(struct strparser *strp, struct sk_buff *skb)
2119{
2120	struct tls_context *tls_ctx = tls_get_ctx(strp->sk);
2121	struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
2122
2123	ctx->decrypted = 0;
2124
2125	ctx->recv_pkt = skb;
2126	strp_pause(strp);
2127
2128	ctx->saved_data_ready(strp->sk);
2129}
2130
2131static void tls_data_ready(struct sock *sk)
2132{
2133	struct tls_context *tls_ctx = tls_get_ctx(sk);
2134	struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
2135	struct sk_psock *psock;
2136
2137	strp_data_ready(&ctx->strp);
2138
2139	psock = sk_psock_get(sk);
2140	if (psock) {
2141		if (!list_empty(&psock->ingress_msg))
2142			ctx->saved_data_ready(sk);
2143		sk_psock_put(sk, psock);
2144	}
2145}
2146
2147void tls_sw_cancel_work_tx(struct tls_context *tls_ctx)
2148{
2149	struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
2150
2151	set_bit(BIT_TX_CLOSING, &ctx->tx_bitmask);
2152	set_bit(BIT_TX_SCHEDULED, &ctx->tx_bitmask);
2153	cancel_delayed_work_sync(&ctx->tx_work.work);
2154}
2155
2156void tls_sw_release_resources_tx(struct sock *sk)
2157{
2158	struct tls_context *tls_ctx = tls_get_ctx(sk);
2159	struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
2160	struct tls_rec *rec, *tmp;
2161	int pending;
2162
2163	/* Wait for any pending async encryptions to complete */
2164	spin_lock_bh(&ctx->encrypt_compl_lock);
2165	ctx->async_notify = true;
2166	pending = atomic_read(&ctx->encrypt_pending);
2167	spin_unlock_bh(&ctx->encrypt_compl_lock);
2168
2169	if (pending)
2170		crypto_wait_req(-EINPROGRESS, &ctx->async_wait);
2171
2172	tls_tx_records(sk, -1);
2173
2174	/* Free up un-sent records in tx_list. First, free
2175	 * the partially sent record if any at head of tx_list.
2176	 */
2177	if (tls_ctx->partially_sent_record) {
2178		tls_free_partial_record(sk, tls_ctx);
2179		rec = list_first_entry(&ctx->tx_list,
2180				       struct tls_rec, list);
2181		list_del(&rec->list);
2182		sk_msg_free(sk, &rec->msg_plaintext);
2183		kfree(rec);
2184	}
2185
2186	list_for_each_entry_safe(rec, tmp, &ctx->tx_list, list) {
2187		list_del(&rec->list);
2188		sk_msg_free(sk, &rec->msg_encrypted);
2189		sk_msg_free(sk, &rec->msg_plaintext);
2190		kfree(rec);
2191	}
2192
2193	crypto_free_aead(ctx->aead_send);
2194	tls_free_open_rec(sk);
2195}
2196
2197void tls_sw_free_ctx_tx(struct tls_context *tls_ctx)
2198{
2199	struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
2200
2201	kfree(ctx);
2202}
2203
2204void tls_sw_release_resources_rx(struct sock *sk)
2205{
2206	struct tls_context *tls_ctx = tls_get_ctx(sk);
2207	struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
2208
2209	kfree(tls_ctx->rx.rec_seq);
2210	kfree(tls_ctx->rx.iv);
2211
2212	if (ctx->aead_recv) {
2213		kfree_skb(ctx->recv_pkt);
2214		ctx->recv_pkt = NULL;
2215		skb_queue_purge(&ctx->rx_list);
2216		crypto_free_aead(ctx->aead_recv);
2217		strp_stop(&ctx->strp);
2218		/* If tls_sw_strparser_arm() was not called (cleanup paths)
2219		 * we still want to strp_stop(), but sk->sk_data_ready was
2220		 * never swapped.
2221		 */
2222		if (ctx->saved_data_ready) {
2223			write_lock_bh(&sk->sk_callback_lock);
2224			sk->sk_data_ready = ctx->saved_data_ready;
2225			write_unlock_bh(&sk->sk_callback_lock);
2226		}
2227	}
2228}
2229
2230void tls_sw_strparser_done(struct tls_context *tls_ctx)
2231{
2232	struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
2233
2234	strp_done(&ctx->strp);
2235}
2236
2237void tls_sw_free_ctx_rx(struct tls_context *tls_ctx)
2238{
2239	struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
2240
2241	kfree(ctx);
2242}
2243
2244void tls_sw_free_resources_rx(struct sock *sk)
2245{
2246	struct tls_context *tls_ctx = tls_get_ctx(sk);
2247
2248	tls_sw_release_resources_rx(sk);
2249	tls_sw_free_ctx_rx(tls_ctx);
2250}
2251
2252/* The work handler to transmitt the encrypted records in tx_list */
2253static void tx_work_handler(struct work_struct *work)
2254{
2255	struct delayed_work *delayed_work = to_delayed_work(work);
2256	struct tx_work *tx_work = container_of(delayed_work,
2257					       struct tx_work, work);
2258	struct sock *sk = tx_work->sk;
2259	struct tls_context *tls_ctx = tls_get_ctx(sk);
2260	struct tls_sw_context_tx *ctx;
2261
2262	if (unlikely(!tls_ctx))
2263		return;
2264
2265	ctx = tls_sw_ctx_tx(tls_ctx);
2266	if (test_bit(BIT_TX_CLOSING, &ctx->tx_bitmask))
2267		return;
2268
2269	if (!test_and_clear_bit(BIT_TX_SCHEDULED, &ctx->tx_bitmask))
2270		return;
2271
2272	if (mutex_trylock(&tls_ctx->tx_lock)) {
2273		lock_sock(sk);
2274		tls_tx_records(sk, -1);
2275		release_sock(sk);
2276		mutex_unlock(&tls_ctx->tx_lock);
2277	} else if (!test_and_set_bit(BIT_TX_SCHEDULED, &ctx->tx_bitmask)) {
2278		/* Someone is holding the tx_lock, they will likely run Tx
2279		 * and cancel the work on their way out of the lock section.
2280		 * Schedule a long delay just in case.
2281		 */
2282		schedule_delayed_work(&ctx->tx_work.work, msecs_to_jiffies(10));
2283	}
2284}
2285
2286void tls_sw_write_space(struct sock *sk, struct tls_context *ctx)
2287{
2288	struct tls_sw_context_tx *tx_ctx = tls_sw_ctx_tx(ctx);
2289
2290	/* Schedule the transmission if tx list is ready */
2291	if (is_tx_ready(tx_ctx) &&
2292	    !test_and_set_bit(BIT_TX_SCHEDULED, &tx_ctx->tx_bitmask))
2293		schedule_delayed_work(&tx_ctx->tx_work.work, 0);
2294}
2295
2296void tls_sw_strparser_arm(struct sock *sk, struct tls_context *tls_ctx)
2297{
2298	struct tls_sw_context_rx *rx_ctx = tls_sw_ctx_rx(tls_ctx);
2299
2300	write_lock_bh(&sk->sk_callback_lock);
2301	rx_ctx->saved_data_ready = sk->sk_data_ready;
2302	sk->sk_data_ready = tls_data_ready;
2303	write_unlock_bh(&sk->sk_callback_lock);
2304
2305	strp_check_rcv(&rx_ctx->strp);
2306}
2307
2308int tls_set_sw_offload(struct sock *sk, struct tls_context *ctx, int tx)
2309{
2310	struct tls_context *tls_ctx = tls_get_ctx(sk);
2311	struct tls_prot_info *prot = &tls_ctx->prot_info;
2312	struct tls_crypto_info *crypto_info;
2313	struct tls12_crypto_info_aes_gcm_128 *gcm_128_info;
2314	struct tls12_crypto_info_aes_gcm_256 *gcm_256_info;
2315	struct tls12_crypto_info_aes_ccm_128 *ccm_128_info;
2316	struct tls_sw_context_tx *sw_ctx_tx = NULL;
2317	struct tls_sw_context_rx *sw_ctx_rx = NULL;
2318	struct cipher_context *cctx;
2319	struct crypto_aead **aead;
2320	struct strp_callbacks cb;
2321	u16 nonce_size, tag_size, iv_size, rec_seq_size, salt_size;
2322	struct crypto_tfm *tfm;
2323	char *iv, *rec_seq, *key, *salt, *cipher_name;
2324	size_t keysize;
2325	int rc = 0;
2326
2327	if (!ctx) {
2328		rc = -EINVAL;
2329		goto out;
2330	}
2331
2332	if (tx) {
2333		if (!ctx->priv_ctx_tx) {
2334			sw_ctx_tx = kzalloc(sizeof(*sw_ctx_tx), GFP_KERNEL);
2335			if (!sw_ctx_tx) {
2336				rc = -ENOMEM;
2337				goto out;
2338			}
2339			ctx->priv_ctx_tx = sw_ctx_tx;
2340		} else {
2341			sw_ctx_tx =
2342				(struct tls_sw_context_tx *)ctx->priv_ctx_tx;
2343		}
2344	} else {
2345		if (!ctx->priv_ctx_rx) {
2346			sw_ctx_rx = kzalloc(sizeof(*sw_ctx_rx), GFP_KERNEL);
2347			if (!sw_ctx_rx) {
2348				rc = -ENOMEM;
2349				goto out;
2350			}
2351			ctx->priv_ctx_rx = sw_ctx_rx;
2352		} else {
2353			sw_ctx_rx =
2354				(struct tls_sw_context_rx *)ctx->priv_ctx_rx;
2355		}
2356	}
2357
2358	if (tx) {
2359		crypto_init_wait(&sw_ctx_tx->async_wait);
2360		spin_lock_init(&sw_ctx_tx->encrypt_compl_lock);
2361		crypto_info = &ctx->crypto_send.info;
2362		cctx = &ctx->tx;
2363		aead = &sw_ctx_tx->aead_send;
2364		INIT_LIST_HEAD(&sw_ctx_tx->tx_list);
2365		INIT_DELAYED_WORK(&sw_ctx_tx->tx_work.work, tx_work_handler);
2366		sw_ctx_tx->tx_work.sk = sk;
2367	} else {
2368		crypto_init_wait(&sw_ctx_rx->async_wait);
2369		spin_lock_init(&sw_ctx_rx->decrypt_compl_lock);
2370		crypto_info = &ctx->crypto_recv.info;
2371		cctx = &ctx->rx;
2372		skb_queue_head_init(&sw_ctx_rx->rx_list);
2373		aead = &sw_ctx_rx->aead_recv;
2374	}
2375
2376	switch (crypto_info->cipher_type) {
2377	case TLS_CIPHER_AES_GCM_128: {
2378		nonce_size = TLS_CIPHER_AES_GCM_128_IV_SIZE;
2379		tag_size = TLS_CIPHER_AES_GCM_128_TAG_SIZE;
2380		iv_size = TLS_CIPHER_AES_GCM_128_IV_SIZE;
2381		iv = ((struct tls12_crypto_info_aes_gcm_128 *)crypto_info)->iv;
2382		rec_seq_size = TLS_CIPHER_AES_GCM_128_REC_SEQ_SIZE;
2383		rec_seq =
2384		 ((struct tls12_crypto_info_aes_gcm_128 *)crypto_info)->rec_seq;
2385		gcm_128_info =
2386			(struct tls12_crypto_info_aes_gcm_128 *)crypto_info;
2387		keysize = TLS_CIPHER_AES_GCM_128_KEY_SIZE;
2388		key = gcm_128_info->key;
2389		salt = gcm_128_info->salt;
2390		salt_size = TLS_CIPHER_AES_GCM_128_SALT_SIZE;
2391		cipher_name = "gcm(aes)";
2392		break;
2393	}
2394	case TLS_CIPHER_AES_GCM_256: {
2395		nonce_size = TLS_CIPHER_AES_GCM_256_IV_SIZE;
2396		tag_size = TLS_CIPHER_AES_GCM_256_TAG_SIZE;
2397		iv_size = TLS_CIPHER_AES_GCM_256_IV_SIZE;
2398		iv = ((struct tls12_crypto_info_aes_gcm_256 *)crypto_info)->iv;
2399		rec_seq_size = TLS_CIPHER_AES_GCM_256_REC_SEQ_SIZE;
2400		rec_seq =
2401		 ((struct tls12_crypto_info_aes_gcm_256 *)crypto_info)->rec_seq;
2402		gcm_256_info =
2403			(struct tls12_crypto_info_aes_gcm_256 *)crypto_info;
2404		keysize = TLS_CIPHER_AES_GCM_256_KEY_SIZE;
2405		key = gcm_256_info->key;
2406		salt = gcm_256_info->salt;
2407		salt_size = TLS_CIPHER_AES_GCM_256_SALT_SIZE;
2408		cipher_name = "gcm(aes)";
2409		break;
2410	}
2411	case TLS_CIPHER_AES_CCM_128: {
2412		nonce_size = TLS_CIPHER_AES_CCM_128_IV_SIZE;
2413		tag_size = TLS_CIPHER_AES_CCM_128_TAG_SIZE;
2414		iv_size = TLS_CIPHER_AES_CCM_128_IV_SIZE;
2415		iv = ((struct tls12_crypto_info_aes_ccm_128 *)crypto_info)->iv;
2416		rec_seq_size = TLS_CIPHER_AES_CCM_128_REC_SEQ_SIZE;
2417		rec_seq =
2418		((struct tls12_crypto_info_aes_ccm_128 *)crypto_info)->rec_seq;
2419		ccm_128_info =
2420		(struct tls12_crypto_info_aes_ccm_128 *)crypto_info;
2421		keysize = TLS_CIPHER_AES_CCM_128_KEY_SIZE;
2422		key = ccm_128_info->key;
2423		salt = ccm_128_info->salt;
2424		salt_size = TLS_CIPHER_AES_CCM_128_SALT_SIZE;
2425		cipher_name = "ccm(aes)";
2426		break;
2427	}
2428	default:
2429		rc = -EINVAL;
2430		goto free_priv;
2431	}
2432
2433	/* Sanity-check the sizes for stack allocations. */
2434	if (iv_size > MAX_IV_SIZE || nonce_size > MAX_IV_SIZE ||
2435	    rec_seq_size > TLS_MAX_REC_SEQ_SIZE) {
2436		rc = -EINVAL;
2437		goto free_priv;
2438	}
2439
2440	if (crypto_info->version == TLS_1_3_VERSION) {
2441		nonce_size = 0;
2442		prot->aad_size = TLS_HEADER_SIZE;
2443		prot->tail_size = 1;
2444	} else {
2445		prot->aad_size = TLS_AAD_SPACE_SIZE;
2446		prot->tail_size = 0;
2447	}
2448
2449	prot->version = crypto_info->version;
2450	prot->cipher_type = crypto_info->cipher_type;
2451	prot->prepend_size = TLS_HEADER_SIZE + nonce_size;
2452	prot->tag_size = tag_size;
2453	prot->overhead_size = prot->prepend_size +
2454			      prot->tag_size + prot->tail_size;
2455	prot->iv_size = iv_size;
2456	prot->salt_size = salt_size;
2457	cctx->iv = kmalloc(iv_size + salt_size, GFP_KERNEL);
2458	if (!cctx->iv) {
2459		rc = -ENOMEM;
2460		goto free_priv;
2461	}
2462	/* Note: 128 & 256 bit salt are the same size */
2463	prot->rec_seq_size = rec_seq_size;
2464	memcpy(cctx->iv, salt, salt_size);
2465	memcpy(cctx->iv + salt_size, iv, iv_size);
2466	cctx->rec_seq = kmemdup(rec_seq, rec_seq_size, GFP_KERNEL);
2467	if (!cctx->rec_seq) {
2468		rc = -ENOMEM;
2469		goto free_iv;
2470	}
2471
2472	if (!*aead) {
2473		*aead = crypto_alloc_aead(cipher_name, 0, 0);
2474		if (IS_ERR(*aead)) {
2475			rc = PTR_ERR(*aead);
2476			*aead = NULL;
2477			goto free_rec_seq;
2478		}
2479	}
2480
2481	ctx->push_pending_record = tls_sw_push_pending_record;
2482
2483	rc = crypto_aead_setkey(*aead, key, keysize);
2484
2485	if (rc)
2486		goto free_aead;
2487
2488	rc = crypto_aead_setauthsize(*aead, prot->tag_size);
2489	if (rc)
2490		goto free_aead;
2491
2492	if (sw_ctx_rx) {
2493		tfm = crypto_aead_tfm(sw_ctx_rx->aead_recv);
2494
2495		if (crypto_info->version == TLS_1_3_VERSION)
2496			sw_ctx_rx->async_capable = 0;
2497		else
2498			sw_ctx_rx->async_capable =
2499				!!(tfm->__crt_alg->cra_flags &
2500				   CRYPTO_ALG_ASYNC);
2501
2502		/* Set up strparser */
2503		memset(&cb, 0, sizeof(cb));
2504		cb.rcv_msg = tls_queue;
2505		cb.parse_msg = tls_read_size;
2506
2507		strp_init(&sw_ctx_rx->strp, sk, &cb);
2508	}
2509
2510	goto out;
2511
2512free_aead:
2513	crypto_free_aead(*aead);
2514	*aead = NULL;
2515free_rec_seq:
2516	kfree(cctx->rec_seq);
2517	cctx->rec_seq = NULL;
2518free_iv:
2519	kfree(cctx->iv);
2520	cctx->iv = NULL;
2521free_priv:
2522	if (tx) {
2523		kfree(ctx->priv_ctx_tx);
2524		ctx->priv_ctx_tx = NULL;
2525	} else {
2526		kfree(ctx->priv_ctx_rx);
2527		ctx->priv_ctx_rx = NULL;
2528	}
2529out:
2530	return rc;
2531}
2532