dbba51b69d212b449ec398aa2cdd26aa221ceb05
[sfrench/cifs-2.6.git] / net / tls / tls_sw.c
1 /*
2  * Copyright (c) 2016-2017, Mellanox Technologies. All rights reserved.
3  * Copyright (c) 2016-2017, Dave Watson <davejwatson@fb.com>. All rights reserved.
4  * Copyright (c) 2016-2017, Lance Chao <lancerchao@fb.com>. All rights reserved.
5  * Copyright (c) 2016, Fridolin Pokorny <fridolin.pokorny@gmail.com>. All rights reserved.
6  * Copyright (c) 2016, Nikos Mavrogiannopoulos <nmav@gnutls.org>. All rights reserved.
7  * Copyright (c) 2018, Covalent IO, Inc. http://covalent.io
8  *
9  * This software is available to you under a choice of one of two
10  * licenses.  You may choose to be licensed under the terms of the GNU
11  * General Public License (GPL) Version 2, available from the file
12  * COPYING in the main directory of this source tree, or the
13  * OpenIB.org BSD license below:
14  *
15  *     Redistribution and use in source and binary forms, with or
16  *     without modification, are permitted provided that the following
17  *     conditions are met:
18  *
19  *      - Redistributions of source code must retain the above
20  *        copyright notice, this list of conditions and the following
21  *        disclaimer.
22  *
23  *      - Redistributions in binary form must reproduce the above
24  *        copyright notice, this list of conditions and the following
25  *        disclaimer in the documentation and/or other materials
26  *        provided with the distribution.
27  *
28  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
29  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
30  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
31  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
32  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
33  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
34  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
35  * SOFTWARE.
36  */
37
38 #include <linux/sched/signal.h>
39 #include <linux/module.h>
40 #include <crypto/aead.h>
41
42 #include <net/strparser.h>
43 #include <net/tls.h>
44
45 static int __skb_nsg(struct sk_buff *skb, int offset, int len,
46                      unsigned int recursion_level)
47 {
48         int start = skb_headlen(skb);
49         int i, chunk = start - offset;
50         struct sk_buff *frag_iter;
51         int elt = 0;
52
53         if (unlikely(recursion_level >= 24))
54                 return -EMSGSIZE;
55
56         if (chunk > 0) {
57                 if (chunk > len)
58                         chunk = len;
59                 elt++;
60                 len -= chunk;
61                 if (len == 0)
62                         return elt;
63                 offset += chunk;
64         }
65
66         for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
67                 int end;
68
69                 WARN_ON(start > offset + len);
70
71                 end = start + skb_frag_size(&skb_shinfo(skb)->frags[i]);
72                 chunk = end - offset;
73                 if (chunk > 0) {
74                         if (chunk > len)
75                                 chunk = len;
76                         elt++;
77                         len -= chunk;
78                         if (len == 0)
79                                 return elt;
80                         offset += chunk;
81                 }
82                 start = end;
83         }
84
85         if (unlikely(skb_has_frag_list(skb))) {
86                 skb_walk_frags(skb, frag_iter) {
87                         int end, ret;
88
89                         WARN_ON(start > offset + len);
90
91                         end = start + frag_iter->len;
92                         chunk = end - offset;
93                         if (chunk > 0) {
94                                 if (chunk > len)
95                                         chunk = len;
96                                 ret = __skb_nsg(frag_iter, offset - start, chunk,
97                                                 recursion_level + 1);
98                                 if (unlikely(ret < 0))
99                                         return ret;
100                                 elt += ret;
101                                 len -= chunk;
102                                 if (len == 0)
103                                         return elt;
104                                 offset += chunk;
105                         }
106                         start = end;
107                 }
108         }
109         BUG_ON(len);
110         return elt;
111 }
112
113 /* Return the number of scatterlist elements required to completely map the
114  * skb, or -EMSGSIZE if the recursion depth is exceeded.
115  */
116 static int skb_nsg(struct sk_buff *skb, int offset, int len)
117 {
118         return __skb_nsg(skb, offset, len, 0);
119 }
120
121 static int padding_length(struct tls_sw_context_rx *ctx,
122                           struct tls_prot_info *prot, struct sk_buff *skb)
123 {
124         struct strp_msg *rxm = strp_msg(skb);
125         int sub = 0;
126
127         /* Determine zero-padding length */
128         if (prot->version == TLS_1_3_VERSION) {
129                 char content_type = 0;
130                 int err;
131                 int back = 17;
132
133                 while (content_type == 0) {
134                         if (back > rxm->full_len - prot->prepend_size)
135                                 return -EBADMSG;
136                         err = skb_copy_bits(skb,
137                                             rxm->offset + rxm->full_len - back,
138                                             &content_type, 1);
139                         if (err)
140                                 return err;
141                         if (content_type)
142                                 break;
143                         sub++;
144                         back++;
145                 }
146                 ctx->control = content_type;
147         }
148         return sub;
149 }
150
151 static void tls_decrypt_done(struct crypto_async_request *req, int err)
152 {
153         struct aead_request *aead_req = (struct aead_request *)req;
154         struct scatterlist *sgout = aead_req->dst;
155         struct scatterlist *sgin = aead_req->src;
156         struct tls_sw_context_rx *ctx;
157         struct tls_context *tls_ctx;
158         struct tls_prot_info *prot;
159         struct scatterlist *sg;
160         struct sk_buff *skb;
161         unsigned int pages;
162         int pending;
163
164         skb = (struct sk_buff *)req->data;
165         tls_ctx = tls_get_ctx(skb->sk);
166         ctx = tls_sw_ctx_rx(tls_ctx);
167         prot = &tls_ctx->prot_info;
168
169         /* Propagate if there was an err */
170         if (err) {
171                 if (err == -EBADMSG)
172                         TLS_INC_STATS(sock_net(skb->sk),
173                                       LINUX_MIB_TLSDECRYPTERROR);
174                 ctx->async_wait.err = err;
175                 tls_err_abort(skb->sk, err);
176         } else {
177                 struct strp_msg *rxm = strp_msg(skb);
178                 int pad;
179
180                 pad = padding_length(ctx, prot, skb);
181                 if (pad < 0) {
182                         ctx->async_wait.err = pad;
183                         tls_err_abort(skb->sk, pad);
184                 } else {
185                         rxm->full_len -= pad;
186                         rxm->offset += prot->prepend_size;
187                         rxm->full_len -= prot->overhead_size;
188                 }
189         }
190
191         /* After using skb->sk to propagate sk through crypto async callback
192          * we need to NULL it again.
193          */
194         skb->sk = NULL;
195
196
197         /* Free the destination pages if skb was not decrypted inplace */
198         if (sgout != sgin) {
199                 /* Skip the first S/G entry as it points to AAD */
200                 for_each_sg(sg_next(sgout), sg, UINT_MAX, pages) {
201                         if (!sg)
202                                 break;
203                         put_page(sg_page(sg));
204                 }
205         }
206
207         kfree(aead_req);
208
209         pending = atomic_dec_return(&ctx->decrypt_pending);
210
211         if (!pending && READ_ONCE(ctx->async_notify))
212                 complete(&ctx->async_wait.completion);
213 }
214
215 static int tls_do_decryption(struct sock *sk,
216                              struct sk_buff *skb,
217                              struct scatterlist *sgin,
218                              struct scatterlist *sgout,
219                              char *iv_recv,
220                              size_t data_len,
221                              struct aead_request *aead_req,
222                              bool async)
223 {
224         struct tls_context *tls_ctx = tls_get_ctx(sk);
225         struct tls_prot_info *prot = &tls_ctx->prot_info;
226         struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
227         int ret;
228
229         aead_request_set_tfm(aead_req, ctx->aead_recv);
230         aead_request_set_ad(aead_req, prot->aad_size);
231         aead_request_set_crypt(aead_req, sgin, sgout,
232                                data_len + prot->tag_size,
233                                (u8 *)iv_recv);
234
235         if (async) {
236                 /* Using skb->sk to push sk through to crypto async callback
237                  * handler. This allows propagating errors up to the socket
238                  * if needed. It _must_ be cleared in the async handler
239                  * before consume_skb is called. We _know_ skb->sk is NULL
240                  * because it is a clone from strparser.
241                  */
242                 skb->sk = sk;
243                 aead_request_set_callback(aead_req,
244                                           CRYPTO_TFM_REQ_MAY_BACKLOG,
245                                           tls_decrypt_done, skb);
246                 atomic_inc(&ctx->decrypt_pending);
247         } else {
248                 aead_request_set_callback(aead_req,
249                                           CRYPTO_TFM_REQ_MAY_BACKLOG,
250                                           crypto_req_done, &ctx->async_wait);
251         }
252
253         ret = crypto_aead_decrypt(aead_req);
254         if (ret == -EINPROGRESS) {
255                 if (async)
256                         return ret;
257
258                 ret = crypto_wait_req(ret, &ctx->async_wait);
259         } else if (ret == -EBADMSG) {
260                 TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSDECRYPTERROR);
261         }
262
263         if (async)
264                 atomic_dec(&ctx->decrypt_pending);
265
266         return ret;
267 }
268
269 static void tls_trim_both_msgs(struct sock *sk, int target_size)
270 {
271         struct tls_context *tls_ctx = tls_get_ctx(sk);
272         struct tls_prot_info *prot = &tls_ctx->prot_info;
273         struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
274         struct tls_rec *rec = ctx->open_rec;
275
276         sk_msg_trim(sk, &rec->msg_plaintext, target_size);
277         if (target_size > 0)
278                 target_size += prot->overhead_size;
279         sk_msg_trim(sk, &rec->msg_encrypted, target_size);
280 }
281
282 static int tls_alloc_encrypted_msg(struct sock *sk, int len)
283 {
284         struct tls_context *tls_ctx = tls_get_ctx(sk);
285         struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
286         struct tls_rec *rec = ctx->open_rec;
287         struct sk_msg *msg_en = &rec->msg_encrypted;
288
289         return sk_msg_alloc(sk, msg_en, len, 0);
290 }
291
292 static int tls_clone_plaintext_msg(struct sock *sk, int required)
293 {
294         struct tls_context *tls_ctx = tls_get_ctx(sk);
295         struct tls_prot_info *prot = &tls_ctx->prot_info;
296         struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
297         struct tls_rec *rec = ctx->open_rec;
298         struct sk_msg *msg_pl = &rec->msg_plaintext;
299         struct sk_msg *msg_en = &rec->msg_encrypted;
300         int skip, len;
301
302         /* We add page references worth len bytes from encrypted sg
303          * at the end of plaintext sg. It is guaranteed that msg_en
304          * has enough required room (ensured by caller).
305          */
306         len = required - msg_pl->sg.size;
307
308         /* Skip initial bytes in msg_en's data to be able to use
309          * same offset of both plain and encrypted data.
310          */
311         skip = prot->prepend_size + msg_pl->sg.size;
312
313         return sk_msg_clone(sk, msg_pl, msg_en, skip, len);
314 }
315
316 static struct tls_rec *tls_get_rec(struct sock *sk)
317 {
318         struct tls_context *tls_ctx = tls_get_ctx(sk);
319         struct tls_prot_info *prot = &tls_ctx->prot_info;
320         struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
321         struct sk_msg *msg_pl, *msg_en;
322         struct tls_rec *rec;
323         int mem_size;
324
325         mem_size = sizeof(struct tls_rec) + crypto_aead_reqsize(ctx->aead_send);
326
327         rec = kzalloc(mem_size, sk->sk_allocation);
328         if (!rec)
329                 return NULL;
330
331         msg_pl = &rec->msg_plaintext;
332         msg_en = &rec->msg_encrypted;
333
334         sk_msg_init(msg_pl);
335         sk_msg_init(msg_en);
336
337         sg_init_table(rec->sg_aead_in, 2);
338         sg_set_buf(&rec->sg_aead_in[0], rec->aad_space, prot->aad_size);
339         sg_unmark_end(&rec->sg_aead_in[1]);
340
341         sg_init_table(rec->sg_aead_out, 2);
342         sg_set_buf(&rec->sg_aead_out[0], rec->aad_space, prot->aad_size);
343         sg_unmark_end(&rec->sg_aead_out[1]);
344
345         return rec;
346 }
347
348 static void tls_free_rec(struct sock *sk, struct tls_rec *rec)
349 {
350         sk_msg_free(sk, &rec->msg_encrypted);
351         sk_msg_free(sk, &rec->msg_plaintext);
352         kfree(rec);
353 }
354
355 static void tls_free_open_rec(struct sock *sk)
356 {
357         struct tls_context *tls_ctx = tls_get_ctx(sk);
358         struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
359         struct tls_rec *rec = ctx->open_rec;
360
361         if (rec) {
362                 tls_free_rec(sk, rec);
363                 ctx->open_rec = NULL;
364         }
365 }
366
367 int tls_tx_records(struct sock *sk, int flags)
368 {
369         struct tls_context *tls_ctx = tls_get_ctx(sk);
370         struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
371         struct tls_rec *rec, *tmp;
372         struct sk_msg *msg_en;
373         int tx_flags, rc = 0;
374
375         if (tls_is_partially_sent_record(tls_ctx)) {
376                 rec = list_first_entry(&ctx->tx_list,
377                                        struct tls_rec, list);
378
379                 if (flags == -1)
380                         tx_flags = rec->tx_flags;
381                 else
382                         tx_flags = flags;
383
384                 rc = tls_push_partial_record(sk, tls_ctx, tx_flags);
385                 if (rc)
386                         goto tx_err;
387
388                 /* Full record has been transmitted.
389                  * Remove the head of tx_list
390                  */
391                 list_del(&rec->list);
392                 sk_msg_free(sk, &rec->msg_plaintext);
393                 kfree(rec);
394         }
395
396         /* Tx all ready records */
397         list_for_each_entry_safe(rec, tmp, &ctx->tx_list, list) {
398                 if (READ_ONCE(rec->tx_ready)) {
399                         if (flags == -1)
400                                 tx_flags = rec->tx_flags;
401                         else
402                                 tx_flags = flags;
403
404                         msg_en = &rec->msg_encrypted;
405                         rc = tls_push_sg(sk, tls_ctx,
406                                          &msg_en->sg.data[msg_en->sg.curr],
407                                          0, tx_flags);
408                         if (rc)
409                                 goto tx_err;
410
411                         list_del(&rec->list);
412                         sk_msg_free(sk, &rec->msg_plaintext);
413                         kfree(rec);
414                 } else {
415                         break;
416                 }
417         }
418
419 tx_err:
420         if (rc < 0 && rc != -EAGAIN)
421                 tls_err_abort(sk, EBADMSG);
422
423         return rc;
424 }
425
426 static void tls_encrypt_done(struct crypto_async_request *req, int err)
427 {
428         struct aead_request *aead_req = (struct aead_request *)req;
429         struct sock *sk = req->data;
430         struct tls_context *tls_ctx = tls_get_ctx(sk);
431         struct tls_prot_info *prot = &tls_ctx->prot_info;
432         struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
433         struct scatterlist *sge;
434         struct sk_msg *msg_en;
435         struct tls_rec *rec;
436         bool ready = false;
437         int pending;
438
439         rec = container_of(aead_req, struct tls_rec, aead_req);
440         msg_en = &rec->msg_encrypted;
441
442         sge = sk_msg_elem(msg_en, msg_en->sg.curr);
443         sge->offset -= prot->prepend_size;
444         sge->length += prot->prepend_size;
445
446         /* Check if error is previously set on socket */
447         if (err || sk->sk_err) {
448                 rec = NULL;
449
450                 /* If err is already set on socket, return the same code */
451                 if (sk->sk_err) {
452                         ctx->async_wait.err = sk->sk_err;
453                 } else {
454                         ctx->async_wait.err = err;
455                         tls_err_abort(sk, err);
456                 }
457         }
458
459         if (rec) {
460                 struct tls_rec *first_rec;
461
462                 /* Mark the record as ready for transmission */
463                 smp_store_mb(rec->tx_ready, true);
464
465                 /* If received record is at head of tx_list, schedule tx */
466                 first_rec = list_first_entry(&ctx->tx_list,
467                                              struct tls_rec, list);
468                 if (rec == first_rec)
469                         ready = true;
470         }
471
472         pending = atomic_dec_return(&ctx->encrypt_pending);
473
474         if (!pending && READ_ONCE(ctx->async_notify))
475                 complete(&ctx->async_wait.completion);
476
477         if (!ready)
478                 return;
479
480         /* Schedule the transmission */
481         if (!test_and_set_bit(BIT_TX_SCHEDULED, &ctx->tx_bitmask))
482                 schedule_delayed_work(&ctx->tx_work.work, 1);
483 }
484
485 static int tls_do_encryption(struct sock *sk,
486                              struct tls_context *tls_ctx,
487                              struct tls_sw_context_tx *ctx,
488                              struct aead_request *aead_req,
489                              size_t data_len, u32 start)
490 {
491         struct tls_prot_info *prot = &tls_ctx->prot_info;
492         struct tls_rec *rec = ctx->open_rec;
493         struct sk_msg *msg_en = &rec->msg_encrypted;
494         struct scatterlist *sge = sk_msg_elem(msg_en, start);
495         int rc, iv_offset = 0;
496
497         /* For CCM based ciphers, first byte of IV is a constant */
498         if (prot->cipher_type == TLS_CIPHER_AES_CCM_128) {
499                 rec->iv_data[0] = TLS_AES_CCM_IV_B0_BYTE;
500                 iv_offset = 1;
501         }
502
503         memcpy(&rec->iv_data[iv_offset], tls_ctx->tx.iv,
504                prot->iv_size + prot->salt_size);
505
506         xor_iv_with_seq(prot->version, rec->iv_data, tls_ctx->tx.rec_seq);
507
508         sge->offset += prot->prepend_size;
509         sge->length -= prot->prepend_size;
510
511         msg_en->sg.curr = start;
512
513         aead_request_set_tfm(aead_req, ctx->aead_send);
514         aead_request_set_ad(aead_req, prot->aad_size);
515         aead_request_set_crypt(aead_req, rec->sg_aead_in,
516                                rec->sg_aead_out,
517                                data_len, rec->iv_data);
518
519         aead_request_set_callback(aead_req, CRYPTO_TFM_REQ_MAY_BACKLOG,
520                                   tls_encrypt_done, sk);
521
522         /* Add the record in tx_list */
523         list_add_tail((struct list_head *)&rec->list, &ctx->tx_list);
524         atomic_inc(&ctx->encrypt_pending);
525
526         rc = crypto_aead_encrypt(aead_req);
527         if (!rc || rc != -EINPROGRESS) {
528                 atomic_dec(&ctx->encrypt_pending);
529                 sge->offset -= prot->prepend_size;
530                 sge->length += prot->prepend_size;
531         }
532
533         if (!rc) {
534                 WRITE_ONCE(rec->tx_ready, true);
535         } else if (rc != -EINPROGRESS) {
536                 list_del(&rec->list);
537                 return rc;
538         }
539
540         /* Unhook the record from context if encryption is not failure */
541         ctx->open_rec = NULL;
542         tls_advance_record_sn(sk, prot, &tls_ctx->tx);
543         return rc;
544 }
545
546 static int tls_split_open_record(struct sock *sk, struct tls_rec *from,
547                                  struct tls_rec **to, struct sk_msg *msg_opl,
548                                  struct sk_msg *msg_oen, u32 split_point,
549                                  u32 tx_overhead_size, u32 *orig_end)
550 {
551         u32 i, j, bytes = 0, apply = msg_opl->apply_bytes;
552         struct scatterlist *sge, *osge, *nsge;
553         u32 orig_size = msg_opl->sg.size;
554         struct scatterlist tmp = { };
555         struct sk_msg *msg_npl;
556         struct tls_rec *new;
557         int ret;
558
559         new = tls_get_rec(sk);
560         if (!new)
561                 return -ENOMEM;
562         ret = sk_msg_alloc(sk, &new->msg_encrypted, msg_opl->sg.size +
563                            tx_overhead_size, 0);
564         if (ret < 0) {
565                 tls_free_rec(sk, new);
566                 return ret;
567         }
568
569         *orig_end = msg_opl->sg.end;
570         i = msg_opl->sg.start;
571         sge = sk_msg_elem(msg_opl, i);
572         while (apply && sge->length) {
573                 if (sge->length > apply) {
574                         u32 len = sge->length - apply;
575
576                         get_page(sg_page(sge));
577                         sg_set_page(&tmp, sg_page(sge), len,
578                                     sge->offset + apply);
579                         sge->length = apply;
580                         bytes += apply;
581                         apply = 0;
582                 } else {
583                         apply -= sge->length;
584                         bytes += sge->length;
585                 }
586
587                 sk_msg_iter_var_next(i);
588                 if (i == msg_opl->sg.end)
589                         break;
590                 sge = sk_msg_elem(msg_opl, i);
591         }
592
593         msg_opl->sg.end = i;
594         msg_opl->sg.curr = i;
595         msg_opl->sg.copybreak = 0;
596         msg_opl->apply_bytes = 0;
597         msg_opl->sg.size = bytes;
598
599         msg_npl = &new->msg_plaintext;
600         msg_npl->apply_bytes = apply;
601         msg_npl->sg.size = orig_size - bytes;
602
603         j = msg_npl->sg.start;
604         nsge = sk_msg_elem(msg_npl, j);
605         if (tmp.length) {
606                 memcpy(nsge, &tmp, sizeof(*nsge));
607                 sk_msg_iter_var_next(j);
608                 nsge = sk_msg_elem(msg_npl, j);
609         }
610
611         osge = sk_msg_elem(msg_opl, i);
612         while (osge->length) {
613                 memcpy(nsge, osge, sizeof(*nsge));
614                 sg_unmark_end(nsge);
615                 sk_msg_iter_var_next(i);
616                 sk_msg_iter_var_next(j);
617                 if (i == *orig_end)
618                         break;
619                 osge = sk_msg_elem(msg_opl, i);
620                 nsge = sk_msg_elem(msg_npl, j);
621         }
622
623         msg_npl->sg.end = j;
624         msg_npl->sg.curr = j;
625         msg_npl->sg.copybreak = 0;
626
627         *to = new;
628         return 0;
629 }
630
631 static void tls_merge_open_record(struct sock *sk, struct tls_rec *to,
632                                   struct tls_rec *from, u32 orig_end)
633 {
634         struct sk_msg *msg_npl = &from->msg_plaintext;
635         struct sk_msg *msg_opl = &to->msg_plaintext;
636         struct scatterlist *osge, *nsge;
637         u32 i, j;
638
639         i = msg_opl->sg.end;
640         sk_msg_iter_var_prev(i);
641         j = msg_npl->sg.start;
642
643         osge = sk_msg_elem(msg_opl, i);
644         nsge = sk_msg_elem(msg_npl, j);
645
646         if (sg_page(osge) == sg_page(nsge) &&
647             osge->offset + osge->length == nsge->offset) {
648                 osge->length += nsge->length;
649                 put_page(sg_page(nsge));
650         }
651
652         msg_opl->sg.end = orig_end;
653         msg_opl->sg.curr = orig_end;
654         msg_opl->sg.copybreak = 0;
655         msg_opl->apply_bytes = msg_opl->sg.size + msg_npl->sg.size;
656         msg_opl->sg.size += msg_npl->sg.size;
657
658         sk_msg_free(sk, &to->msg_encrypted);
659         sk_msg_xfer_full(&to->msg_encrypted, &from->msg_encrypted);
660
661         kfree(from);
662 }
663
664 static int tls_push_record(struct sock *sk, int flags,
665                            unsigned char record_type)
666 {
667         struct tls_context *tls_ctx = tls_get_ctx(sk);
668         struct tls_prot_info *prot = &tls_ctx->prot_info;
669         struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
670         struct tls_rec *rec = ctx->open_rec, *tmp = NULL;
671         u32 i, split_point, uninitialized_var(orig_end);
672         struct sk_msg *msg_pl, *msg_en;
673         struct aead_request *req;
674         bool split;
675         int rc;
676
677         if (!rec)
678                 return 0;
679
680         msg_pl = &rec->msg_plaintext;
681         msg_en = &rec->msg_encrypted;
682
683         split_point = msg_pl->apply_bytes;
684         split = split_point && split_point < msg_pl->sg.size;
685         if (split) {
686                 rc = tls_split_open_record(sk, rec, &tmp, msg_pl, msg_en,
687                                            split_point, prot->overhead_size,
688                                            &orig_end);
689                 if (rc < 0)
690                         return rc;
691                 sk_msg_trim(sk, msg_en, msg_pl->sg.size +
692                             prot->overhead_size);
693         }
694
695         rec->tx_flags = flags;
696         req = &rec->aead_req;
697
698         i = msg_pl->sg.end;
699         sk_msg_iter_var_prev(i);
700
701         rec->content_type = record_type;
702         if (prot->version == TLS_1_3_VERSION) {
703                 /* Add content type to end of message.  No padding added */
704                 sg_set_buf(&rec->sg_content_type, &rec->content_type, 1);
705                 sg_mark_end(&rec->sg_content_type);
706                 sg_chain(msg_pl->sg.data, msg_pl->sg.end + 1,
707                          &rec->sg_content_type);
708         } else {
709                 sg_mark_end(sk_msg_elem(msg_pl, i));
710         }
711
712         i = msg_pl->sg.start;
713         sg_chain(rec->sg_aead_in, 2, rec->inplace_crypto ?
714                  &msg_en->sg.data[i] : &msg_pl->sg.data[i]);
715
716         i = msg_en->sg.end;
717         sk_msg_iter_var_prev(i);
718         sg_mark_end(sk_msg_elem(msg_en, i));
719
720         i = msg_en->sg.start;
721         sg_chain(rec->sg_aead_out, 2, &msg_en->sg.data[i]);
722
723         tls_make_aad(rec->aad_space, msg_pl->sg.size + prot->tail_size,
724                      tls_ctx->tx.rec_seq, prot->rec_seq_size,
725                      record_type, prot->version);
726
727         tls_fill_prepend(tls_ctx,
728                          page_address(sg_page(&msg_en->sg.data[i])) +
729                          msg_en->sg.data[i].offset,
730                          msg_pl->sg.size + prot->tail_size,
731                          record_type, prot->version);
732
733         tls_ctx->pending_open_record_frags = false;
734
735         rc = tls_do_encryption(sk, tls_ctx, ctx, req,
736                                msg_pl->sg.size + prot->tail_size, i);
737         if (rc < 0) {
738                 if (rc != -EINPROGRESS) {
739                         tls_err_abort(sk, EBADMSG);
740                         if (split) {
741                                 tls_ctx->pending_open_record_frags = true;
742                                 tls_merge_open_record(sk, rec, tmp, orig_end);
743                         }
744                 }
745                 ctx->async_capable = 1;
746                 return rc;
747         } else if (split) {
748                 msg_pl = &tmp->msg_plaintext;
749                 msg_en = &tmp->msg_encrypted;
750                 sk_msg_trim(sk, msg_en, msg_pl->sg.size + prot->overhead_size);
751                 tls_ctx->pending_open_record_frags = true;
752                 ctx->open_rec = tmp;
753         }
754
755         return tls_tx_records(sk, flags);
756 }
757
758 static int bpf_exec_tx_verdict(struct sk_msg *msg, struct sock *sk,
759                                bool full_record, u8 record_type,
760                                size_t *copied, int flags)
761 {
762         struct tls_context *tls_ctx = tls_get_ctx(sk);
763         struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
764         struct sk_msg msg_redir = { };
765         struct sk_psock *psock;
766         struct sock *sk_redir;
767         struct tls_rec *rec;
768         bool enospc, policy;
769         int err = 0, send;
770         u32 delta = 0;
771
772         policy = !(flags & MSG_SENDPAGE_NOPOLICY);
773         psock = sk_psock_get(sk);
774         if (!psock || !policy) {
775                 err = tls_push_record(sk, flags, record_type);
776                 if (err) {
777                         *copied -= sk_msg_free(sk, msg);
778                         tls_free_open_rec(sk);
779                 }
780                 return err;
781         }
782 more_data:
783         enospc = sk_msg_full(msg);
784         if (psock->eval == __SK_NONE) {
785                 delta = msg->sg.size;
786                 psock->eval = sk_psock_msg_verdict(sk, psock, msg);
787                 if (delta < msg->sg.size)
788                         delta -= msg->sg.size;
789                 else
790                         delta = 0;
791         }
792         if (msg->cork_bytes && msg->cork_bytes > msg->sg.size &&
793             !enospc && !full_record) {
794                 err = -ENOSPC;
795                 goto out_err;
796         }
797         msg->cork_bytes = 0;
798         send = msg->sg.size;
799         if (msg->apply_bytes && msg->apply_bytes < send)
800                 send = msg->apply_bytes;
801
802         switch (psock->eval) {
803         case __SK_PASS:
804                 err = tls_push_record(sk, flags, record_type);
805                 if (err < 0) {
806                         *copied -= sk_msg_free(sk, msg);
807                         tls_free_open_rec(sk);
808                         goto out_err;
809                 }
810                 break;
811         case __SK_REDIRECT:
812                 sk_redir = psock->sk_redir;
813                 memcpy(&msg_redir, msg, sizeof(*msg));
814                 if (msg->apply_bytes < send)
815                         msg->apply_bytes = 0;
816                 else
817                         msg->apply_bytes -= send;
818                 sk_msg_return_zero(sk, msg, send);
819                 msg->sg.size -= send;
820                 release_sock(sk);
821                 err = tcp_bpf_sendmsg_redir(sk_redir, &msg_redir, send, flags);
822                 lock_sock(sk);
823                 if (err < 0) {
824                         *copied -= sk_msg_free_nocharge(sk, &msg_redir);
825                         msg->sg.size = 0;
826                 }
827                 if (msg->sg.size == 0)
828                         tls_free_open_rec(sk);
829                 break;
830         case __SK_DROP:
831         default:
832                 sk_msg_free_partial(sk, msg, send);
833                 if (msg->apply_bytes < send)
834                         msg->apply_bytes = 0;
835                 else
836                         msg->apply_bytes -= send;
837                 if (msg->sg.size == 0)
838                         tls_free_open_rec(sk);
839                 *copied -= (send + delta);
840                 err = -EACCES;
841         }
842
843         if (likely(!err)) {
844                 bool reset_eval = !ctx->open_rec;
845
846                 rec = ctx->open_rec;
847                 if (rec) {
848                         msg = &rec->msg_plaintext;
849                         if (!msg->apply_bytes)
850                                 reset_eval = true;
851                 }
852                 if (reset_eval) {
853                         psock->eval = __SK_NONE;
854                         if (psock->sk_redir) {
855                                 sock_put(psock->sk_redir);
856                                 psock->sk_redir = NULL;
857                         }
858                 }
859                 if (rec)
860                         goto more_data;
861         }
862  out_err:
863         sk_psock_put(sk, psock);
864         return err;
865 }
866
867 static int tls_sw_push_pending_record(struct sock *sk, int flags)
868 {
869         struct tls_context *tls_ctx = tls_get_ctx(sk);
870         struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
871         struct tls_rec *rec = ctx->open_rec;
872         struct sk_msg *msg_pl;
873         size_t copied;
874
875         if (!rec)
876                 return 0;
877
878         msg_pl = &rec->msg_plaintext;
879         copied = msg_pl->sg.size;
880         if (!copied)
881                 return 0;
882
883         return bpf_exec_tx_verdict(msg_pl, sk, true, TLS_RECORD_TYPE_DATA,
884                                    &copied, flags);
885 }
886
887 int tls_sw_sendmsg(struct sock *sk, struct msghdr *msg, size_t size)
888 {
889         long timeo = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT);
890         struct tls_context *tls_ctx = tls_get_ctx(sk);
891         struct tls_prot_info *prot = &tls_ctx->prot_info;
892         struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
893         bool async_capable = ctx->async_capable;
894         unsigned char record_type = TLS_RECORD_TYPE_DATA;
895         bool is_kvec = iov_iter_is_kvec(&msg->msg_iter);
896         bool eor = !(msg->msg_flags & MSG_MORE);
897         size_t try_to_copy, copied = 0;
898         struct sk_msg *msg_pl, *msg_en;
899         struct tls_rec *rec;
900         int required_size;
901         int num_async = 0;
902         bool full_record;
903         int record_room;
904         int num_zc = 0;
905         int orig_size;
906         int ret = 0;
907
908         if (msg->msg_flags & ~(MSG_MORE | MSG_DONTWAIT | MSG_NOSIGNAL))
909                 return -ENOTSUPP;
910
911         mutex_lock(&tls_ctx->tx_lock);
912         lock_sock(sk);
913
914         if (unlikely(msg->msg_controllen)) {
915                 ret = tls_proccess_cmsg(sk, msg, &record_type);
916                 if (ret) {
917                         if (ret == -EINPROGRESS)
918                                 num_async++;
919                         else if (ret != -EAGAIN)
920                                 goto send_end;
921                 }
922         }
923
924         while (msg_data_left(msg)) {
925                 if (sk->sk_err) {
926                         ret = -sk->sk_err;
927                         goto send_end;
928                 }
929
930                 if (ctx->open_rec)
931                         rec = ctx->open_rec;
932                 else
933                         rec = ctx->open_rec = tls_get_rec(sk);
934                 if (!rec) {
935                         ret = -ENOMEM;
936                         goto send_end;
937                 }
938
939                 msg_pl = &rec->msg_plaintext;
940                 msg_en = &rec->msg_encrypted;
941
942                 orig_size = msg_pl->sg.size;
943                 full_record = false;
944                 try_to_copy = msg_data_left(msg);
945                 record_room = TLS_MAX_PAYLOAD_SIZE - msg_pl->sg.size;
946                 if (try_to_copy >= record_room) {
947                         try_to_copy = record_room;
948                         full_record = true;
949                 }
950
951                 required_size = msg_pl->sg.size + try_to_copy +
952                                 prot->overhead_size;
953
954                 if (!sk_stream_memory_free(sk))
955                         goto wait_for_sndbuf;
956
957 alloc_encrypted:
958                 ret = tls_alloc_encrypted_msg(sk, required_size);
959                 if (ret) {
960                         if (ret != -ENOSPC)
961                                 goto wait_for_memory;
962
963                         /* Adjust try_to_copy according to the amount that was
964                          * actually allocated. The difference is due
965                          * to max sg elements limit
966                          */
967                         try_to_copy -= required_size - msg_en->sg.size;
968                         full_record = true;
969                 }
970
971                 if (!is_kvec && (full_record || eor) && !async_capable) {
972                         u32 first = msg_pl->sg.end;
973
974                         ret = sk_msg_zerocopy_from_iter(sk, &msg->msg_iter,
975                                                         msg_pl, try_to_copy);
976                         if (ret)
977                                 goto fallback_to_reg_send;
978
979                         rec->inplace_crypto = 0;
980
981                         num_zc++;
982                         copied += try_to_copy;
983
984                         sk_msg_sg_copy_set(msg_pl, first);
985                         ret = bpf_exec_tx_verdict(msg_pl, sk, full_record,
986                                                   record_type, &copied,
987                                                   msg->msg_flags);
988                         if (ret) {
989                                 if (ret == -EINPROGRESS)
990                                         num_async++;
991                                 else if (ret == -ENOMEM)
992                                         goto wait_for_memory;
993                                 else if (ctx->open_rec && ret == -ENOSPC)
994                                         goto rollback_iter;
995                                 else if (ret != -EAGAIN)
996                                         goto send_end;
997                         }
998                         continue;
999 rollback_iter:
1000                         copied -= try_to_copy;
1001                         sk_msg_sg_copy_clear(msg_pl, first);
1002                         iov_iter_revert(&msg->msg_iter,
1003                                         msg_pl->sg.size - orig_size);
1004 fallback_to_reg_send:
1005                         sk_msg_trim(sk, msg_pl, orig_size);
1006                 }
1007
1008                 required_size = msg_pl->sg.size + try_to_copy;
1009
1010                 ret = tls_clone_plaintext_msg(sk, required_size);
1011                 if (ret) {
1012                         if (ret != -ENOSPC)
1013                                 goto send_end;
1014
1015                         /* Adjust try_to_copy according to the amount that was
1016                          * actually allocated. The difference is due
1017                          * to max sg elements limit
1018                          */
1019                         try_to_copy -= required_size - msg_pl->sg.size;
1020                         full_record = true;
1021                         sk_msg_trim(sk, msg_en,
1022                                     msg_pl->sg.size + prot->overhead_size);
1023                 }
1024
1025                 if (try_to_copy) {
1026                         ret = sk_msg_memcopy_from_iter(sk, &msg->msg_iter,
1027                                                        msg_pl, try_to_copy);
1028                         if (ret < 0)
1029                                 goto trim_sgl;
1030                 }
1031
1032                 /* Open records defined only if successfully copied, otherwise
1033                  * we would trim the sg but not reset the open record frags.
1034                  */
1035                 tls_ctx->pending_open_record_frags = true;
1036                 copied += try_to_copy;
1037                 if (full_record || eor) {
1038                         ret = bpf_exec_tx_verdict(msg_pl, sk, full_record,
1039                                                   record_type, &copied,
1040                                                   msg->msg_flags);
1041                         if (ret) {
1042                                 if (ret == -EINPROGRESS)
1043                                         num_async++;
1044                                 else if (ret == -ENOMEM)
1045                                         goto wait_for_memory;
1046                                 else if (ret != -EAGAIN) {
1047                                         if (ret == -ENOSPC)
1048                                                 ret = 0;
1049                                         goto send_end;
1050                                 }
1051                         }
1052                 }
1053
1054                 continue;
1055
1056 wait_for_sndbuf:
1057                 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1058 wait_for_memory:
1059                 ret = sk_stream_wait_memory(sk, &timeo);
1060                 if (ret) {
1061 trim_sgl:
1062                         if (ctx->open_rec)
1063                                 tls_trim_both_msgs(sk, orig_size);
1064                         goto send_end;
1065                 }
1066
1067                 if (ctx->open_rec && msg_en->sg.size < required_size)
1068                         goto alloc_encrypted;
1069         }
1070
1071         if (!num_async) {
1072                 goto send_end;
1073         } else if (num_zc) {
1074                 /* Wait for pending encryptions to get completed */
1075                 smp_store_mb(ctx->async_notify, true);
1076
1077                 if (atomic_read(&ctx->encrypt_pending))
1078                         crypto_wait_req(-EINPROGRESS, &ctx->async_wait);
1079                 else
1080                         reinit_completion(&ctx->async_wait.completion);
1081
1082                 WRITE_ONCE(ctx->async_notify, false);
1083
1084                 if (ctx->async_wait.err) {
1085                         ret = ctx->async_wait.err;
1086                         copied = 0;
1087                 }
1088         }
1089
1090         /* Transmit if any encryptions have completed */
1091         if (test_and_clear_bit(BIT_TX_SCHEDULED, &ctx->tx_bitmask)) {
1092                 cancel_delayed_work(&ctx->tx_work.work);
1093                 tls_tx_records(sk, msg->msg_flags);
1094         }
1095
1096 send_end:
1097         ret = sk_stream_error(sk, msg->msg_flags, ret);
1098
1099         release_sock(sk);
1100         mutex_unlock(&tls_ctx->tx_lock);
1101         return copied ? copied : ret;
1102 }
1103
1104 static int tls_sw_do_sendpage(struct sock *sk, struct page *page,
1105                               int offset, size_t size, int flags)
1106 {
1107         long timeo = sock_sndtimeo(sk, flags & MSG_DONTWAIT);
1108         struct tls_context *tls_ctx = tls_get_ctx(sk);
1109         struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
1110         struct tls_prot_info *prot = &tls_ctx->prot_info;
1111         unsigned char record_type = TLS_RECORD_TYPE_DATA;
1112         struct sk_msg *msg_pl;
1113         struct tls_rec *rec;
1114         int num_async = 0;
1115         size_t copied = 0;
1116         bool full_record;
1117         int record_room;
1118         int ret = 0;
1119         bool eor;
1120
1121         eor = !(flags & (MSG_MORE | MSG_SENDPAGE_NOTLAST));
1122         sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);
1123
1124         /* Call the sk_stream functions to manage the sndbuf mem. */
1125         while (size > 0) {
1126                 size_t copy, required_size;
1127
1128                 if (sk->sk_err) {
1129                         ret = -sk->sk_err;
1130                         goto sendpage_end;
1131                 }
1132
1133                 if (ctx->open_rec)
1134                         rec = ctx->open_rec;
1135                 else
1136                         rec = ctx->open_rec = tls_get_rec(sk);
1137                 if (!rec) {
1138                         ret = -ENOMEM;
1139                         goto sendpage_end;
1140                 }
1141
1142                 msg_pl = &rec->msg_plaintext;
1143
1144                 full_record = false;
1145                 record_room = TLS_MAX_PAYLOAD_SIZE - msg_pl->sg.size;
1146                 copy = size;
1147                 if (copy >= record_room) {
1148                         copy = record_room;
1149                         full_record = true;
1150                 }
1151
1152                 required_size = msg_pl->sg.size + copy + prot->overhead_size;
1153
1154                 if (!sk_stream_memory_free(sk))
1155                         goto wait_for_sndbuf;
1156 alloc_payload:
1157                 ret = tls_alloc_encrypted_msg(sk, required_size);
1158                 if (ret) {
1159                         if (ret != -ENOSPC)
1160                                 goto wait_for_memory;
1161
1162                         /* Adjust copy according to the amount that was
1163                          * actually allocated. The difference is due
1164                          * to max sg elements limit
1165                          */
1166                         copy -= required_size - msg_pl->sg.size;
1167                         full_record = true;
1168                 }
1169
1170                 sk_msg_page_add(msg_pl, page, copy, offset);
1171                 sk_mem_charge(sk, copy);
1172
1173                 offset += copy;
1174                 size -= copy;
1175                 copied += copy;
1176
1177                 tls_ctx->pending_open_record_frags = true;
1178                 if (full_record || eor || sk_msg_full(msg_pl)) {
1179                         rec->inplace_crypto = 0;
1180                         ret = bpf_exec_tx_verdict(msg_pl, sk, full_record,
1181                                                   record_type, &copied, flags);
1182                         if (ret) {
1183                                 if (ret == -EINPROGRESS)
1184                                         num_async++;
1185                                 else if (ret == -ENOMEM)
1186                                         goto wait_for_memory;
1187                                 else if (ret != -EAGAIN) {
1188                                         if (ret == -ENOSPC)
1189                                                 ret = 0;
1190                                         goto sendpage_end;
1191                                 }
1192                         }
1193                 }
1194                 continue;
1195 wait_for_sndbuf:
1196                 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1197 wait_for_memory:
1198                 ret = sk_stream_wait_memory(sk, &timeo);
1199                 if (ret) {
1200                         if (ctx->open_rec)
1201                                 tls_trim_both_msgs(sk, msg_pl->sg.size);
1202                         goto sendpage_end;
1203                 }
1204
1205                 if (ctx->open_rec)
1206                         goto alloc_payload;
1207         }
1208
1209         if (num_async) {
1210                 /* Transmit if any encryptions have completed */
1211                 if (test_and_clear_bit(BIT_TX_SCHEDULED, &ctx->tx_bitmask)) {
1212                         cancel_delayed_work(&ctx->tx_work.work);
1213                         tls_tx_records(sk, flags);
1214                 }
1215         }
1216 sendpage_end:
1217         ret = sk_stream_error(sk, flags, ret);
1218         return copied ? copied : ret;
1219 }
1220
1221 int tls_sw_sendpage_locked(struct sock *sk, struct page *page,
1222                            int offset, size_t size, int flags)
1223 {
1224         if (flags & ~(MSG_MORE | MSG_DONTWAIT | MSG_NOSIGNAL |
1225                       MSG_SENDPAGE_NOTLAST | MSG_SENDPAGE_NOPOLICY |
1226                       MSG_NO_SHARED_FRAGS))
1227                 return -ENOTSUPP;
1228
1229         return tls_sw_do_sendpage(sk, page, offset, size, flags);
1230 }
1231
1232 int tls_sw_sendpage(struct sock *sk, struct page *page,
1233                     int offset, size_t size, int flags)
1234 {
1235         struct tls_context *tls_ctx = tls_get_ctx(sk);
1236         int ret;
1237
1238         if (flags & ~(MSG_MORE | MSG_DONTWAIT | MSG_NOSIGNAL |
1239                       MSG_SENDPAGE_NOTLAST | MSG_SENDPAGE_NOPOLICY))
1240                 return -ENOTSUPP;
1241
1242         mutex_lock(&tls_ctx->tx_lock);
1243         lock_sock(sk);
1244         ret = tls_sw_do_sendpage(sk, page, offset, size, flags);
1245         release_sock(sk);
1246         mutex_unlock(&tls_ctx->tx_lock);
1247         return ret;
1248 }
1249
1250 static struct sk_buff *tls_wait_data(struct sock *sk, struct sk_psock *psock,
1251                                      int flags, long timeo, int *err)
1252 {
1253         struct tls_context *tls_ctx = tls_get_ctx(sk);
1254         struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
1255         struct sk_buff *skb;
1256         DEFINE_WAIT_FUNC(wait, woken_wake_function);
1257
1258         while (!(skb = ctx->recv_pkt) && sk_psock_queue_empty(psock)) {
1259                 if (sk->sk_err) {
1260                         *err = sock_error(sk);
1261                         return NULL;
1262                 }
1263
1264                 if (sk->sk_shutdown & RCV_SHUTDOWN)
1265                         return NULL;
1266
1267                 if (sock_flag(sk, SOCK_DONE))
1268                         return NULL;
1269
1270                 if ((flags & MSG_DONTWAIT) || !timeo) {
1271                         *err = -EAGAIN;
1272                         return NULL;
1273                 }
1274
1275                 add_wait_queue(sk_sleep(sk), &wait);
1276                 sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk);
1277                 sk_wait_event(sk, &timeo,
1278                               ctx->recv_pkt != skb ||
1279                               !sk_psock_queue_empty(psock),
1280                               &wait);
1281                 sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk);
1282                 remove_wait_queue(sk_sleep(sk), &wait);
1283
1284                 /* Handle signals */
1285                 if (signal_pending(current)) {
1286                         *err = sock_intr_errno(timeo);
1287                         return NULL;
1288                 }
1289         }
1290
1291         return skb;
1292 }
1293
1294 static int tls_setup_from_iter(struct sock *sk, struct iov_iter *from,
1295                                int length, int *pages_used,
1296                                unsigned int *size_used,
1297                                struct scatterlist *to,
1298                                int to_max_pages)
1299 {
1300         int rc = 0, i = 0, num_elem = *pages_used, maxpages;
1301         struct page *pages[MAX_SKB_FRAGS];
1302         unsigned int size = *size_used;
1303         ssize_t copied, use;
1304         size_t offset;
1305
1306         while (length > 0) {
1307                 i = 0;
1308                 maxpages = to_max_pages - num_elem;
1309                 if (maxpages == 0) {
1310                         rc = -EFAULT;
1311                         goto out;
1312                 }
1313                 copied = iov_iter_get_pages(from, pages,
1314                                             length,
1315                                             maxpages, &offset);
1316                 if (copied <= 0) {
1317                         rc = -EFAULT;
1318                         goto out;
1319                 }
1320
1321                 iov_iter_advance(from, copied);
1322
1323                 length -= copied;
1324                 size += copied;
1325                 while (copied) {
1326                         use = min_t(int, copied, PAGE_SIZE - offset);
1327
1328                         sg_set_page(&to[num_elem],
1329                                     pages[i], use, offset);
1330                         sg_unmark_end(&to[num_elem]);
1331                         /* We do not uncharge memory from this API */
1332
1333                         offset = 0;
1334                         copied -= use;
1335
1336                         i++;
1337                         num_elem++;
1338                 }
1339         }
1340         /* Mark the end in the last sg entry if newly added */
1341         if (num_elem > *pages_used)
1342                 sg_mark_end(&to[num_elem - 1]);
1343 out:
1344         if (rc)
1345                 iov_iter_revert(from, size - *size_used);
1346         *size_used = size;
1347         *pages_used = num_elem;
1348
1349         return rc;
1350 }
1351
1352 /* This function decrypts the input skb into either out_iov or in out_sg
1353  * or in skb buffers itself. The input parameter 'zc' indicates if
1354  * zero-copy mode needs to be tried or not. With zero-copy mode, either
1355  * out_iov or out_sg must be non-NULL. In case both out_iov and out_sg are
1356  * NULL, then the decryption happens inside skb buffers itself, i.e.
1357  * zero-copy gets disabled and 'zc' is updated.
1358  */
1359
1360 static int decrypt_internal(struct sock *sk, struct sk_buff *skb,
1361                             struct iov_iter *out_iov,
1362                             struct scatterlist *out_sg,
1363                             int *chunk, bool *zc, bool async)
1364 {
1365         struct tls_context *tls_ctx = tls_get_ctx(sk);
1366         struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
1367         struct tls_prot_info *prot = &tls_ctx->prot_info;
1368         struct strp_msg *rxm = strp_msg(skb);
1369         int n_sgin, n_sgout, nsg, mem_size, aead_size, err, pages = 0;
1370         struct aead_request *aead_req;
1371         struct sk_buff *unused;
1372         u8 *aad, *iv, *mem = NULL;
1373         struct scatterlist *sgin = NULL;
1374         struct scatterlist *sgout = NULL;
1375         const int data_len = rxm->full_len - prot->overhead_size +
1376                              prot->tail_size;
1377         int iv_offset = 0;
1378
1379         if (*zc && (out_iov || out_sg)) {
1380                 if (out_iov)
1381                         n_sgout = iov_iter_npages(out_iov, INT_MAX) + 1;
1382                 else
1383                         n_sgout = sg_nents(out_sg);
1384                 n_sgin = skb_nsg(skb, rxm->offset + prot->prepend_size,
1385                                  rxm->full_len - prot->prepend_size);
1386         } else {
1387                 n_sgout = 0;
1388                 *zc = false;
1389                 n_sgin = skb_cow_data(skb, 0, &unused);
1390         }
1391
1392         if (n_sgin < 1)
1393                 return -EBADMSG;
1394
1395         /* Increment to accommodate AAD */
1396         n_sgin = n_sgin + 1;
1397
1398         nsg = n_sgin + n_sgout;
1399
1400         aead_size = sizeof(*aead_req) + crypto_aead_reqsize(ctx->aead_recv);
1401         mem_size = aead_size + (nsg * sizeof(struct scatterlist));
1402         mem_size = mem_size + prot->aad_size;
1403         mem_size = mem_size + crypto_aead_ivsize(ctx->aead_recv);
1404
1405         /* Allocate a single block of memory which contains
1406          * aead_req || sgin[] || sgout[] || aad || iv.
1407          * This order achieves correct alignment for aead_req, sgin, sgout.
1408          */
1409         mem = kmalloc(mem_size, sk->sk_allocation);
1410         if (!mem)
1411                 return -ENOMEM;
1412
1413         /* Segment the allocated memory */
1414         aead_req = (struct aead_request *)mem;
1415         sgin = (struct scatterlist *)(mem + aead_size);
1416         sgout = sgin + n_sgin;
1417         aad = (u8 *)(sgout + n_sgout);
1418         iv = aad + prot->aad_size;
1419
1420         /* For CCM based ciphers, first byte of nonce+iv is always '2' */
1421         if (prot->cipher_type == TLS_CIPHER_AES_CCM_128) {
1422                 iv[0] = 2;
1423                 iv_offset = 1;
1424         }
1425
1426         /* Prepare IV */
1427         err = skb_copy_bits(skb, rxm->offset + TLS_HEADER_SIZE,
1428                             iv + iv_offset + prot->salt_size,
1429                             prot->iv_size);
1430         if (err < 0) {
1431                 kfree(mem);
1432                 return err;
1433         }
1434         if (prot->version == TLS_1_3_VERSION)
1435                 memcpy(iv + iv_offset, tls_ctx->rx.iv,
1436                        crypto_aead_ivsize(ctx->aead_recv));
1437         else
1438                 memcpy(iv + iv_offset, tls_ctx->rx.iv, prot->salt_size);
1439
1440         xor_iv_with_seq(prot->version, iv, tls_ctx->rx.rec_seq);
1441
1442         /* Prepare AAD */
1443         tls_make_aad(aad, rxm->full_len - prot->overhead_size +
1444                      prot->tail_size,
1445                      tls_ctx->rx.rec_seq, prot->rec_seq_size,
1446                      ctx->control, prot->version);
1447
1448         /* Prepare sgin */
1449         sg_init_table(sgin, n_sgin);
1450         sg_set_buf(&sgin[0], aad, prot->aad_size);
1451         err = skb_to_sgvec(skb, &sgin[1],
1452                            rxm->offset + prot->prepend_size,
1453                            rxm->full_len - prot->prepend_size);
1454         if (err < 0) {
1455                 kfree(mem);
1456                 return err;
1457         }
1458
1459         if (n_sgout) {
1460                 if (out_iov) {
1461                         sg_init_table(sgout, n_sgout);
1462                         sg_set_buf(&sgout[0], aad, prot->aad_size);
1463
1464                         *chunk = 0;
1465                         err = tls_setup_from_iter(sk, out_iov, data_len,
1466                                                   &pages, chunk, &sgout[1],
1467                                                   (n_sgout - 1));
1468                         if (err < 0)
1469                                 goto fallback_to_reg_recv;
1470                 } else if (out_sg) {
1471                         memcpy(sgout, out_sg, n_sgout * sizeof(*sgout));
1472                 } else {
1473                         goto fallback_to_reg_recv;
1474                 }
1475         } else {
1476 fallback_to_reg_recv:
1477                 sgout = sgin;
1478                 pages = 0;
1479                 *chunk = data_len;
1480                 *zc = false;
1481         }
1482
1483         /* Prepare and submit AEAD request */
1484         err = tls_do_decryption(sk, skb, sgin, sgout, iv,
1485                                 data_len, aead_req, async);
1486         if (err == -EINPROGRESS)
1487                 return err;
1488
1489         /* Release the pages in case iov was mapped to pages */
1490         for (; pages > 0; pages--)
1491                 put_page(sg_page(&sgout[pages]));
1492
1493         kfree(mem);
1494         return err;
1495 }
1496
1497 static int decrypt_skb_update(struct sock *sk, struct sk_buff *skb,
1498                               struct iov_iter *dest, int *chunk, bool *zc,
1499                               bool async)
1500 {
1501         struct tls_context *tls_ctx = tls_get_ctx(sk);
1502         struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
1503         struct tls_prot_info *prot = &tls_ctx->prot_info;
1504         struct strp_msg *rxm = strp_msg(skb);
1505         int pad, err = 0;
1506
1507         if (!ctx->decrypted) {
1508                 if (tls_ctx->rx_conf == TLS_HW) {
1509                         err = tls_device_decrypted(sk, tls_ctx, skb, rxm);
1510                         if (err < 0)
1511                                 return err;
1512                 }
1513
1514                 /* Still not decrypted after tls_device */
1515                 if (!ctx->decrypted) {
1516                         err = decrypt_internal(sk, skb, dest, NULL, chunk, zc,
1517                                                async);
1518                         if (err < 0) {
1519                                 if (err == -EINPROGRESS)
1520                                         tls_advance_record_sn(sk, prot,
1521                                                               &tls_ctx->rx);
1522
1523                                 return err;
1524                         }
1525                 } else {
1526                         *zc = false;
1527                 }
1528
1529                 pad = padding_length(ctx, prot, skb);
1530                 if (pad < 0)
1531                         return pad;
1532
1533                 rxm->full_len -= pad;
1534                 rxm->offset += prot->prepend_size;
1535                 rxm->full_len -= prot->overhead_size;
1536                 tls_advance_record_sn(sk, prot, &tls_ctx->rx);
1537                 ctx->decrypted = 1;
1538                 ctx->saved_data_ready(sk);
1539         } else {
1540                 *zc = false;
1541         }
1542
1543         return err;
1544 }
1545
1546 int decrypt_skb(struct sock *sk, struct sk_buff *skb,
1547                 struct scatterlist *sgout)
1548 {
1549         bool zc = true;
1550         int chunk;
1551
1552         return decrypt_internal(sk, skb, NULL, sgout, &chunk, &zc, false);
1553 }
1554
1555 static bool tls_sw_advance_skb(struct sock *sk, struct sk_buff *skb,
1556                                unsigned int len)
1557 {
1558         struct tls_context *tls_ctx = tls_get_ctx(sk);
1559         struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
1560
1561         if (skb) {
1562                 struct strp_msg *rxm = strp_msg(skb);
1563
1564                 if (len < rxm->full_len) {
1565                         rxm->offset += len;
1566                         rxm->full_len -= len;
1567                         return false;
1568                 }
1569                 consume_skb(skb);
1570         }
1571
1572         /* Finished with message */
1573         ctx->recv_pkt = NULL;
1574         __strp_unpause(&ctx->strp);
1575
1576         return true;
1577 }
1578
1579 /* This function traverses the rx_list in tls receive context to copies the
1580  * decrypted records into the buffer provided by caller zero copy is not
1581  * true. Further, the records are removed from the rx_list if it is not a peek
1582  * case and the record has been consumed completely.
1583  */
1584 static int process_rx_list(struct tls_sw_context_rx *ctx,
1585                            struct msghdr *msg,
1586                            u8 *control,
1587                            bool *cmsg,
1588                            size_t skip,
1589                            size_t len,
1590                            bool zc,
1591                            bool is_peek)
1592 {
1593         struct sk_buff *skb = skb_peek(&ctx->rx_list);
1594         u8 ctrl = *control;
1595         u8 msgc = *cmsg;
1596         struct tls_msg *tlm;
1597         ssize_t copied = 0;
1598
1599         /* Set the record type in 'control' if caller didn't pass it */
1600         if (!ctrl && skb) {
1601                 tlm = tls_msg(skb);
1602                 ctrl = tlm->control;
1603         }
1604
1605         while (skip && skb) {
1606                 struct strp_msg *rxm = strp_msg(skb);
1607                 tlm = tls_msg(skb);
1608
1609                 /* Cannot process a record of different type */
1610                 if (ctrl != tlm->control)
1611                         return 0;
1612
1613                 if (skip < rxm->full_len)
1614                         break;
1615
1616                 skip = skip - rxm->full_len;
1617                 skb = skb_peek_next(skb, &ctx->rx_list);
1618         }
1619
1620         while (len && skb) {
1621                 struct sk_buff *next_skb;
1622                 struct strp_msg *rxm = strp_msg(skb);
1623                 int chunk = min_t(unsigned int, rxm->full_len - skip, len);
1624
1625                 tlm = tls_msg(skb);
1626
1627                 /* Cannot process a record of different type */
1628                 if (ctrl != tlm->control)
1629                         return 0;
1630
1631                 /* Set record type if not already done. For a non-data record,
1632                  * do not proceed if record type could not be copied.
1633                  */
1634                 if (!msgc) {
1635                         int cerr = put_cmsg(msg, SOL_TLS, TLS_GET_RECORD_TYPE,
1636                                             sizeof(ctrl), &ctrl);
1637                         msgc = true;
1638                         if (ctrl != TLS_RECORD_TYPE_DATA) {
1639                                 if (cerr || msg->msg_flags & MSG_CTRUNC)
1640                                         return -EIO;
1641
1642                                 *cmsg = msgc;
1643                         }
1644                 }
1645
1646                 if (!zc || (rxm->full_len - skip) > len) {
1647                         int err = skb_copy_datagram_msg(skb, rxm->offset + skip,
1648                                                     msg, chunk);
1649                         if (err < 0)
1650                                 return err;
1651                 }
1652
1653                 len = len - chunk;
1654                 copied = copied + chunk;
1655
1656                 /* Consume the data from record if it is non-peek case*/
1657                 if (!is_peek) {
1658                         rxm->offset = rxm->offset + chunk;
1659                         rxm->full_len = rxm->full_len - chunk;
1660
1661                         /* Return if there is unconsumed data in the record */
1662                         if (rxm->full_len - skip)
1663                                 break;
1664                 }
1665
1666                 /* The remaining skip-bytes must lie in 1st record in rx_list.
1667                  * So from the 2nd record, 'skip' should be 0.
1668                  */
1669                 skip = 0;
1670
1671                 if (msg)
1672                         msg->msg_flags |= MSG_EOR;
1673
1674                 next_skb = skb_peek_next(skb, &ctx->rx_list);
1675
1676                 if (!is_peek) {
1677                         skb_unlink(skb, &ctx->rx_list);
1678                         consume_skb(skb);
1679                 }
1680
1681                 skb = next_skb;
1682         }
1683
1684         *control = ctrl;
1685         return copied;
1686 }
1687
1688 int tls_sw_recvmsg(struct sock *sk,
1689                    struct msghdr *msg,
1690                    size_t len,
1691                    int nonblock,
1692                    int flags,
1693                    int *addr_len)
1694 {
1695         struct tls_context *tls_ctx = tls_get_ctx(sk);
1696         struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
1697         struct tls_prot_info *prot = &tls_ctx->prot_info;
1698         struct sk_psock *psock;
1699         unsigned char control = 0;
1700         ssize_t decrypted = 0;
1701         struct strp_msg *rxm;
1702         struct tls_msg *tlm;
1703         struct sk_buff *skb;
1704         ssize_t copied = 0;
1705         bool cmsg = false;
1706         int target, err = 0;
1707         long timeo;
1708         bool is_kvec = iov_iter_is_kvec(&msg->msg_iter);
1709         bool is_peek = flags & MSG_PEEK;
1710         int num_async = 0;
1711
1712         flags |= nonblock;
1713
1714         if (unlikely(flags & MSG_ERRQUEUE))
1715                 return sock_recv_errqueue(sk, msg, len, SOL_IP, IP_RECVERR);
1716
1717         psock = sk_psock_get(sk);
1718         lock_sock(sk);
1719
1720         /* Process pending decrypted records. It must be non-zero-copy */
1721         err = process_rx_list(ctx, msg, &control, &cmsg, 0, len, false,
1722                               is_peek);
1723         if (err < 0) {
1724                 tls_err_abort(sk, err);
1725                 goto end;
1726         } else {
1727                 copied = err;
1728         }
1729
1730         if (len <= copied)
1731                 goto recv_end;
1732
1733         target = sock_rcvlowat(sk, flags & MSG_WAITALL, len);
1734         len = len - copied;
1735         timeo = sock_rcvtimeo(sk, flags & MSG_DONTWAIT);
1736
1737         while (len && (decrypted + copied < target || ctx->recv_pkt)) {
1738                 bool retain_skb = false;
1739                 bool zc = false;
1740                 int to_decrypt;
1741                 int chunk = 0;
1742                 bool async_capable;
1743                 bool async = false;
1744
1745                 skb = tls_wait_data(sk, psock, flags, timeo, &err);
1746                 if (!skb) {
1747                         if (psock) {
1748                                 int ret = __tcp_bpf_recvmsg(sk, psock,
1749                                                             msg, len, flags);
1750
1751                                 if (ret > 0) {
1752                                         decrypted += ret;
1753                                         len -= ret;
1754                                         continue;
1755                                 }
1756                         }
1757                         goto recv_end;
1758                 } else {
1759                         tlm = tls_msg(skb);
1760                         if (prot->version == TLS_1_3_VERSION)
1761                                 tlm->control = 0;
1762                         else
1763                                 tlm->control = ctx->control;
1764                 }
1765
1766                 rxm = strp_msg(skb);
1767
1768                 to_decrypt = rxm->full_len - prot->overhead_size;
1769
1770                 if (to_decrypt <= len && !is_kvec && !is_peek &&
1771                     ctx->control == TLS_RECORD_TYPE_DATA &&
1772                     prot->version != TLS_1_3_VERSION)
1773                         zc = true;
1774
1775                 /* Do not use async mode if record is non-data */
1776                 if (ctx->control == TLS_RECORD_TYPE_DATA)
1777                         async_capable = ctx->async_capable;
1778                 else
1779                         async_capable = false;
1780
1781                 err = decrypt_skb_update(sk, skb, &msg->msg_iter,
1782                                          &chunk, &zc, async_capable);
1783                 if (err < 0 && err != -EINPROGRESS) {
1784                         tls_err_abort(sk, EBADMSG);
1785                         goto recv_end;
1786                 }
1787
1788                 if (err == -EINPROGRESS) {
1789                         async = true;
1790                         num_async++;
1791                 } else if (prot->version == TLS_1_3_VERSION) {
1792                         tlm->control = ctx->control;
1793                 }
1794
1795                 /* If the type of records being processed is not known yet,
1796                  * set it to record type just dequeued. If it is already known,
1797                  * but does not match the record type just dequeued, go to end.
1798                  * We always get record type here since for tls1.2, record type
1799                  * is known just after record is dequeued from stream parser.
1800                  * For tls1.3, we disable async.
1801                  */
1802
1803                 if (!control)
1804                         control = tlm->control;
1805                 else if (control != tlm->control)
1806                         goto recv_end;
1807
1808                 if (!cmsg) {
1809                         int cerr;
1810
1811                         cerr = put_cmsg(msg, SOL_TLS, TLS_GET_RECORD_TYPE,
1812                                         sizeof(control), &control);
1813                         cmsg = true;
1814                         if (control != TLS_RECORD_TYPE_DATA) {
1815                                 if (cerr || msg->msg_flags & MSG_CTRUNC) {
1816                                         err = -EIO;
1817                                         goto recv_end;
1818                                 }
1819                         }
1820                 }
1821
1822                 if (async)
1823                         goto pick_next_record;
1824
1825                 if (!zc) {
1826                         if (rxm->full_len > len) {
1827                                 retain_skb = true;
1828                                 chunk = len;
1829                         } else {
1830                                 chunk = rxm->full_len;
1831                         }
1832
1833                         err = skb_copy_datagram_msg(skb, rxm->offset,
1834                                                     msg, chunk);
1835                         if (err < 0)
1836                                 goto recv_end;
1837
1838                         if (!is_peek) {
1839                                 rxm->offset = rxm->offset + chunk;
1840                                 rxm->full_len = rxm->full_len - chunk;
1841                         }
1842                 }
1843
1844 pick_next_record:
1845                 if (chunk > len)
1846                         chunk = len;
1847
1848                 decrypted += chunk;
1849                 len -= chunk;
1850
1851                 /* For async or peek case, queue the current skb */
1852                 if (async || is_peek || retain_skb) {
1853                         skb_queue_tail(&ctx->rx_list, skb);
1854                         skb = NULL;
1855                 }
1856
1857                 if (tls_sw_advance_skb(sk, skb, chunk)) {
1858                         /* Return full control message to
1859                          * userspace before trying to parse
1860                          * another message type
1861                          */
1862                         msg->msg_flags |= MSG_EOR;
1863                         if (ctx->control != TLS_RECORD_TYPE_DATA)
1864                                 goto recv_end;
1865                 } else {
1866                         break;
1867                 }
1868         }
1869
1870 recv_end:
1871         if (num_async) {
1872                 /* Wait for all previously submitted records to be decrypted */
1873                 smp_store_mb(ctx->async_notify, true);
1874                 if (atomic_read(&ctx->decrypt_pending)) {
1875                         err = crypto_wait_req(-EINPROGRESS, &ctx->async_wait);
1876                         if (err) {
1877                                 /* one of async decrypt failed */
1878                                 tls_err_abort(sk, err);
1879                                 copied = 0;
1880                                 decrypted = 0;
1881                                 goto end;
1882                         }
1883                 } else {
1884                         reinit_completion(&ctx->async_wait.completion);
1885                 }
1886                 WRITE_ONCE(ctx->async_notify, false);
1887
1888                 /* Drain records from the rx_list & copy if required */
1889                 if (is_peek || is_kvec)
1890                         err = process_rx_list(ctx, msg, &control, &cmsg, copied,
1891                                               decrypted, false, is_peek);
1892                 else
1893                         err = process_rx_list(ctx, msg, &control, &cmsg, 0,
1894                                               decrypted, true, is_peek);
1895                 if (err < 0) {
1896                         tls_err_abort(sk, err);
1897                         copied = 0;
1898                         goto end;
1899                 }
1900         }
1901
1902         copied += decrypted;
1903
1904 end:
1905         release_sock(sk);
1906         if (psock)
1907                 sk_psock_put(sk, psock);
1908         return copied ? : err;
1909 }
1910
1911 ssize_t tls_sw_splice_read(struct socket *sock,  loff_t *ppos,
1912                            struct pipe_inode_info *pipe,
1913                            size_t len, unsigned int flags)
1914 {
1915         struct tls_context *tls_ctx = tls_get_ctx(sock->sk);
1916         struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
1917         struct strp_msg *rxm = NULL;
1918         struct sock *sk = sock->sk;
1919         struct sk_buff *skb;
1920         ssize_t copied = 0;
1921         int err = 0;
1922         long timeo;
1923         int chunk;
1924         bool zc = false;
1925
1926         lock_sock(sk);
1927
1928         timeo = sock_rcvtimeo(sk, flags & MSG_DONTWAIT);
1929
1930         skb = tls_wait_data(sk, NULL, flags, timeo, &err);
1931         if (!skb)
1932                 goto splice_read_end;
1933
1934         if (!ctx->decrypted) {
1935                 err = decrypt_skb_update(sk, skb, NULL, &chunk, &zc, false);
1936
1937                 /* splice does not support reading control messages */
1938                 if (ctx->control != TLS_RECORD_TYPE_DATA) {
1939                         err = -ENOTSUPP;
1940                         goto splice_read_end;
1941                 }
1942
1943                 if (err < 0) {
1944                         tls_err_abort(sk, EBADMSG);
1945                         goto splice_read_end;
1946                 }
1947                 ctx->decrypted = 1;
1948         }
1949         rxm = strp_msg(skb);
1950
1951         chunk = min_t(unsigned int, rxm->full_len, len);
1952         copied = skb_splice_bits(skb, sk, rxm->offset, pipe, chunk, flags);
1953         if (copied < 0)
1954                 goto splice_read_end;
1955
1956         if (likely(!(flags & MSG_PEEK)))
1957                 tls_sw_advance_skb(sk, skb, copied);
1958
1959 splice_read_end:
1960         release_sock(sk);
1961         return copied ? : err;
1962 }
1963
1964 bool tls_sw_stream_read(const struct sock *sk)
1965 {
1966         struct tls_context *tls_ctx = tls_get_ctx(sk);
1967         struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
1968         bool ingress_empty = true;
1969         struct sk_psock *psock;
1970
1971         rcu_read_lock();
1972         psock = sk_psock(sk);
1973         if (psock)
1974                 ingress_empty = list_empty(&psock->ingress_msg);
1975         rcu_read_unlock();
1976
1977         return !ingress_empty || ctx->recv_pkt ||
1978                 !skb_queue_empty(&ctx->rx_list);
1979 }
1980
1981 static int tls_read_size(struct strparser *strp, struct sk_buff *skb)
1982 {
1983         struct tls_context *tls_ctx = tls_get_ctx(strp->sk);
1984         struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
1985         struct tls_prot_info *prot = &tls_ctx->prot_info;
1986         char header[TLS_HEADER_SIZE + MAX_IV_SIZE];
1987         struct strp_msg *rxm = strp_msg(skb);
1988         size_t cipher_overhead;
1989         size_t data_len = 0;
1990         int ret;
1991
1992         /* Verify that we have a full TLS header, or wait for more data */
1993         if (rxm->offset + prot->prepend_size > skb->len)
1994                 return 0;
1995
1996         /* Sanity-check size of on-stack buffer. */
1997         if (WARN_ON(prot->prepend_size > sizeof(header))) {
1998                 ret = -EINVAL;
1999                 goto read_failure;
2000         }
2001
2002         /* Linearize header to local buffer */
2003         ret = skb_copy_bits(skb, rxm->offset, header, prot->prepend_size);
2004
2005         if (ret < 0)
2006                 goto read_failure;
2007
2008         ctx->control = header[0];
2009
2010         data_len = ((header[4] & 0xFF) | (header[3] << 8));
2011
2012         cipher_overhead = prot->tag_size;
2013         if (prot->version != TLS_1_3_VERSION)
2014                 cipher_overhead += prot->iv_size;
2015
2016         if (data_len > TLS_MAX_PAYLOAD_SIZE + cipher_overhead +
2017             prot->tail_size) {
2018                 ret = -EMSGSIZE;
2019                 goto read_failure;
2020         }
2021         if (data_len < cipher_overhead) {
2022                 ret = -EBADMSG;
2023                 goto read_failure;
2024         }
2025
2026         /* Note that both TLS1.3 and TLS1.2 use TLS_1_2 version here */
2027         if (header[1] != TLS_1_2_VERSION_MINOR ||
2028             header[2] != TLS_1_2_VERSION_MAJOR) {
2029                 ret = -EINVAL;
2030                 goto read_failure;
2031         }
2032
2033         tls_device_rx_resync_new_rec(strp->sk, data_len + TLS_HEADER_SIZE,
2034                                      TCP_SKB_CB(skb)->seq + rxm->offset);
2035         return data_len + TLS_HEADER_SIZE;
2036
2037 read_failure:
2038         tls_err_abort(strp->sk, ret);
2039
2040         return ret;
2041 }
2042
2043 static void tls_queue(struct strparser *strp, struct sk_buff *skb)
2044 {
2045         struct tls_context *tls_ctx = tls_get_ctx(strp->sk);
2046         struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
2047
2048         ctx->decrypted = 0;
2049
2050         ctx->recv_pkt = skb;
2051         strp_pause(strp);
2052
2053         ctx->saved_data_ready(strp->sk);
2054 }
2055
2056 static void tls_data_ready(struct sock *sk)
2057 {
2058         struct tls_context *tls_ctx = tls_get_ctx(sk);
2059         struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
2060         struct sk_psock *psock;
2061
2062         strp_data_ready(&ctx->strp);
2063
2064         psock = sk_psock_get(sk);
2065         if (psock && !list_empty(&psock->ingress_msg)) {
2066                 ctx->saved_data_ready(sk);
2067                 sk_psock_put(sk, psock);
2068         }
2069 }
2070
2071 void tls_sw_cancel_work_tx(struct tls_context *tls_ctx)
2072 {
2073         struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
2074
2075         set_bit(BIT_TX_CLOSING, &ctx->tx_bitmask);
2076         set_bit(BIT_TX_SCHEDULED, &ctx->tx_bitmask);
2077         cancel_delayed_work_sync(&ctx->tx_work.work);
2078 }
2079
2080 void tls_sw_release_resources_tx(struct sock *sk)
2081 {
2082         struct tls_context *tls_ctx = tls_get_ctx(sk);
2083         struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
2084         struct tls_rec *rec, *tmp;
2085
2086         /* Wait for any pending async encryptions to complete */
2087         smp_store_mb(ctx->async_notify, true);
2088         if (atomic_read(&ctx->encrypt_pending))
2089                 crypto_wait_req(-EINPROGRESS, &ctx->async_wait);
2090
2091         tls_tx_records(sk, -1);
2092
2093         /* Free up un-sent records in tx_list. First, free
2094          * the partially sent record if any at head of tx_list.
2095          */
2096         if (tls_free_partial_record(sk, tls_ctx)) {
2097                 rec = list_first_entry(&ctx->tx_list,
2098                                        struct tls_rec, list);
2099                 list_del(&rec->list);
2100                 sk_msg_free(sk, &rec->msg_plaintext);
2101                 kfree(rec);
2102         }
2103
2104         list_for_each_entry_safe(rec, tmp, &ctx->tx_list, list) {
2105                 list_del(&rec->list);
2106                 sk_msg_free(sk, &rec->msg_encrypted);
2107                 sk_msg_free(sk, &rec->msg_plaintext);
2108                 kfree(rec);
2109         }
2110
2111         crypto_free_aead(ctx->aead_send);
2112         tls_free_open_rec(sk);
2113 }
2114
2115 void tls_sw_free_ctx_tx(struct tls_context *tls_ctx)
2116 {
2117         struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
2118
2119         kfree(ctx);
2120 }
2121
2122 void tls_sw_release_resources_rx(struct sock *sk)
2123 {
2124         struct tls_context *tls_ctx = tls_get_ctx(sk);
2125         struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
2126
2127         kfree(tls_ctx->rx.rec_seq);
2128         kfree(tls_ctx->rx.iv);
2129
2130         if (ctx->aead_recv) {
2131                 kfree_skb(ctx->recv_pkt);
2132                 ctx->recv_pkt = NULL;
2133                 skb_queue_purge(&ctx->rx_list);
2134                 crypto_free_aead(ctx->aead_recv);
2135                 strp_stop(&ctx->strp);
2136                 /* If tls_sw_strparser_arm() was not called (cleanup paths)
2137                  * we still want to strp_stop(), but sk->sk_data_ready was
2138                  * never swapped.
2139                  */
2140                 if (ctx->saved_data_ready) {
2141                         write_lock_bh(&sk->sk_callback_lock);
2142                         sk->sk_data_ready = ctx->saved_data_ready;
2143                         write_unlock_bh(&sk->sk_callback_lock);
2144                 }
2145         }
2146 }
2147
2148 void tls_sw_strparser_done(struct tls_context *tls_ctx)
2149 {
2150         struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
2151
2152         strp_done(&ctx->strp);
2153 }
2154
2155 void tls_sw_free_ctx_rx(struct tls_context *tls_ctx)
2156 {
2157         struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
2158
2159         kfree(ctx);
2160 }
2161
2162 void tls_sw_free_resources_rx(struct sock *sk)
2163 {
2164         struct tls_context *tls_ctx = tls_get_ctx(sk);
2165
2166         tls_sw_release_resources_rx(sk);
2167         tls_sw_free_ctx_rx(tls_ctx);
2168 }
2169
2170 /* The work handler to transmitt the encrypted records in tx_list */
2171 static void tx_work_handler(struct work_struct *work)
2172 {
2173         struct delayed_work *delayed_work = to_delayed_work(work);
2174         struct tx_work *tx_work = container_of(delayed_work,
2175                                                struct tx_work, work);
2176         struct sock *sk = tx_work->sk;
2177         struct tls_context *tls_ctx = tls_get_ctx(sk);
2178         struct tls_sw_context_tx *ctx;
2179
2180         if (unlikely(!tls_ctx))
2181                 return;
2182
2183         ctx = tls_sw_ctx_tx(tls_ctx);
2184         if (test_bit(BIT_TX_CLOSING, &ctx->tx_bitmask))
2185                 return;
2186
2187         if (!test_and_clear_bit(BIT_TX_SCHEDULED, &ctx->tx_bitmask))
2188                 return;
2189         mutex_lock(&tls_ctx->tx_lock);
2190         lock_sock(sk);
2191         tls_tx_records(sk, -1);
2192         release_sock(sk);
2193         mutex_unlock(&tls_ctx->tx_lock);
2194 }
2195
2196 void tls_sw_write_space(struct sock *sk, struct tls_context *ctx)
2197 {
2198         struct tls_sw_context_tx *tx_ctx = tls_sw_ctx_tx(ctx);
2199
2200         /* Schedule the transmission if tx list is ready */
2201         if (is_tx_ready(tx_ctx) &&
2202             !test_and_set_bit(BIT_TX_SCHEDULED, &tx_ctx->tx_bitmask))
2203                 schedule_delayed_work(&tx_ctx->tx_work.work, 0);
2204 }
2205
2206 void tls_sw_strparser_arm(struct sock *sk, struct tls_context *tls_ctx)
2207 {
2208         struct tls_sw_context_rx *rx_ctx = tls_sw_ctx_rx(tls_ctx);
2209
2210         write_lock_bh(&sk->sk_callback_lock);
2211         rx_ctx->saved_data_ready = sk->sk_data_ready;
2212         sk->sk_data_ready = tls_data_ready;
2213         write_unlock_bh(&sk->sk_callback_lock);
2214
2215         strp_check_rcv(&rx_ctx->strp);
2216 }
2217
2218 int tls_set_sw_offload(struct sock *sk, struct tls_context *ctx, int tx)
2219 {
2220         struct tls_context *tls_ctx = tls_get_ctx(sk);
2221         struct tls_prot_info *prot = &tls_ctx->prot_info;
2222         struct tls_crypto_info *crypto_info;
2223         struct tls12_crypto_info_aes_gcm_128 *gcm_128_info;
2224         struct tls12_crypto_info_aes_gcm_256 *gcm_256_info;
2225         struct tls12_crypto_info_aes_ccm_128 *ccm_128_info;
2226         struct tls_sw_context_tx *sw_ctx_tx = NULL;
2227         struct tls_sw_context_rx *sw_ctx_rx = NULL;
2228         struct cipher_context *cctx;
2229         struct crypto_aead **aead;
2230         struct strp_callbacks cb;
2231         u16 nonce_size, tag_size, iv_size, rec_seq_size, salt_size;
2232         struct crypto_tfm *tfm;
2233         char *iv, *rec_seq, *key, *salt, *cipher_name;
2234         size_t keysize;
2235         int rc = 0;
2236
2237         if (!ctx) {
2238                 rc = -EINVAL;
2239                 goto out;
2240         }
2241
2242         if (tx) {
2243                 if (!ctx->priv_ctx_tx) {
2244                         sw_ctx_tx = kzalloc(sizeof(*sw_ctx_tx), GFP_KERNEL);
2245                         if (!sw_ctx_tx) {
2246                                 rc = -ENOMEM;
2247                                 goto out;
2248                         }
2249                         ctx->priv_ctx_tx = sw_ctx_tx;
2250                 } else {
2251                         sw_ctx_tx =
2252                                 (struct tls_sw_context_tx *)ctx->priv_ctx_tx;
2253                 }
2254         } else {
2255                 if (!ctx->priv_ctx_rx) {
2256                         sw_ctx_rx = kzalloc(sizeof(*sw_ctx_rx), GFP_KERNEL);
2257                         if (!sw_ctx_rx) {
2258                                 rc = -ENOMEM;
2259                                 goto out;
2260                         }
2261                         ctx->priv_ctx_rx = sw_ctx_rx;
2262                 } else {
2263                         sw_ctx_rx =
2264                                 (struct tls_sw_context_rx *)ctx->priv_ctx_rx;
2265                 }
2266         }
2267
2268         if (tx) {
2269                 crypto_init_wait(&sw_ctx_tx->async_wait);
2270                 crypto_info = &ctx->crypto_send.info;
2271                 cctx = &ctx->tx;
2272                 aead = &sw_ctx_tx->aead_send;
2273                 INIT_LIST_HEAD(&sw_ctx_tx->tx_list);
2274                 INIT_DELAYED_WORK(&sw_ctx_tx->tx_work.work, tx_work_handler);
2275                 sw_ctx_tx->tx_work.sk = sk;
2276         } else {
2277                 crypto_init_wait(&sw_ctx_rx->async_wait);
2278                 crypto_info = &ctx->crypto_recv.info;
2279                 cctx = &ctx->rx;
2280                 skb_queue_head_init(&sw_ctx_rx->rx_list);
2281                 aead = &sw_ctx_rx->aead_recv;
2282         }
2283
2284         switch (crypto_info->cipher_type) {
2285         case TLS_CIPHER_AES_GCM_128: {
2286                 nonce_size = TLS_CIPHER_AES_GCM_128_IV_SIZE;
2287                 tag_size = TLS_CIPHER_AES_GCM_128_TAG_SIZE;
2288                 iv_size = TLS_CIPHER_AES_GCM_128_IV_SIZE;
2289                 iv = ((struct tls12_crypto_info_aes_gcm_128 *)crypto_info)->iv;
2290                 rec_seq_size = TLS_CIPHER_AES_GCM_128_REC_SEQ_SIZE;
2291                 rec_seq =
2292                  ((struct tls12_crypto_info_aes_gcm_128 *)crypto_info)->rec_seq;
2293                 gcm_128_info =
2294                         (struct tls12_crypto_info_aes_gcm_128 *)crypto_info;
2295                 keysize = TLS_CIPHER_AES_GCM_128_KEY_SIZE;
2296                 key = gcm_128_info->key;
2297                 salt = gcm_128_info->salt;
2298                 salt_size = TLS_CIPHER_AES_GCM_128_SALT_SIZE;
2299                 cipher_name = "gcm(aes)";
2300                 break;
2301         }
2302         case TLS_CIPHER_AES_GCM_256: {
2303                 nonce_size = TLS_CIPHER_AES_GCM_256_IV_SIZE;
2304                 tag_size = TLS_CIPHER_AES_GCM_256_TAG_SIZE;
2305                 iv_size = TLS_CIPHER_AES_GCM_256_IV_SIZE;
2306                 iv = ((struct tls12_crypto_info_aes_gcm_256 *)crypto_info)->iv;
2307                 rec_seq_size = TLS_CIPHER_AES_GCM_256_REC_SEQ_SIZE;
2308                 rec_seq =
2309                  ((struct tls12_crypto_info_aes_gcm_256 *)crypto_info)->rec_seq;
2310                 gcm_256_info =
2311                         (struct tls12_crypto_info_aes_gcm_256 *)crypto_info;
2312                 keysize = TLS_CIPHER_AES_GCM_256_KEY_SIZE;
2313                 key = gcm_256_info->key;
2314                 salt = gcm_256_info->salt;
2315                 salt_size = TLS_CIPHER_AES_GCM_256_SALT_SIZE;
2316                 cipher_name = "gcm(aes)";
2317                 break;
2318         }
2319         case TLS_CIPHER_AES_CCM_128: {
2320                 nonce_size = TLS_CIPHER_AES_CCM_128_IV_SIZE;
2321                 tag_size = TLS_CIPHER_AES_CCM_128_TAG_SIZE;
2322                 iv_size = TLS_CIPHER_AES_CCM_128_IV_SIZE;
2323                 iv = ((struct tls12_crypto_info_aes_ccm_128 *)crypto_info)->iv;
2324                 rec_seq_size = TLS_CIPHER_AES_CCM_128_REC_SEQ_SIZE;
2325                 rec_seq =
2326                 ((struct tls12_crypto_info_aes_ccm_128 *)crypto_info)->rec_seq;
2327                 ccm_128_info =
2328                 (struct tls12_crypto_info_aes_ccm_128 *)crypto_info;
2329                 keysize = TLS_CIPHER_AES_CCM_128_KEY_SIZE;
2330                 key = ccm_128_info->key;
2331                 salt = ccm_128_info->salt;
2332                 salt_size = TLS_CIPHER_AES_CCM_128_SALT_SIZE;
2333                 cipher_name = "ccm(aes)";
2334                 break;
2335         }
2336         default:
2337                 rc = -EINVAL;
2338                 goto free_priv;
2339         }
2340
2341         /* Sanity-check the sizes for stack allocations. */
2342         if (iv_size > MAX_IV_SIZE || nonce_size > MAX_IV_SIZE ||
2343             rec_seq_size > TLS_MAX_REC_SEQ_SIZE) {
2344                 rc = -EINVAL;
2345                 goto free_priv;
2346         }
2347
2348         if (crypto_info->version == TLS_1_3_VERSION) {
2349                 nonce_size = 0;
2350                 prot->aad_size = TLS_HEADER_SIZE;
2351                 prot->tail_size = 1;
2352         } else {
2353                 prot->aad_size = TLS_AAD_SPACE_SIZE;
2354                 prot->tail_size = 0;
2355         }
2356
2357         prot->version = crypto_info->version;
2358         prot->cipher_type = crypto_info->cipher_type;
2359         prot->prepend_size = TLS_HEADER_SIZE + nonce_size;
2360         prot->tag_size = tag_size;
2361         prot->overhead_size = prot->prepend_size +
2362                               prot->tag_size + prot->tail_size;
2363         prot->iv_size = iv_size;
2364         prot->salt_size = salt_size;
2365         cctx->iv = kmalloc(iv_size + salt_size, GFP_KERNEL);
2366         if (!cctx->iv) {
2367                 rc = -ENOMEM;
2368                 goto free_priv;
2369         }
2370         /* Note: 128 & 256 bit salt are the same size */
2371         prot->rec_seq_size = rec_seq_size;
2372         memcpy(cctx->iv, salt, salt_size);
2373         memcpy(cctx->iv + salt_size, iv, iv_size);
2374         cctx->rec_seq = kmemdup(rec_seq, rec_seq_size, GFP_KERNEL);
2375         if (!cctx->rec_seq) {
2376                 rc = -ENOMEM;
2377                 goto free_iv;
2378         }
2379
2380         if (!*aead) {
2381                 *aead = crypto_alloc_aead(cipher_name, 0, 0);
2382                 if (IS_ERR(*aead)) {
2383                         rc = PTR_ERR(*aead);
2384                         *aead = NULL;
2385                         goto free_rec_seq;
2386                 }
2387         }
2388
2389         ctx->push_pending_record = tls_sw_push_pending_record;
2390
2391         rc = crypto_aead_setkey(*aead, key, keysize);
2392
2393         if (rc)
2394                 goto free_aead;
2395
2396         rc = crypto_aead_setauthsize(*aead, prot->tag_size);
2397         if (rc)
2398                 goto free_aead;
2399
2400         if (sw_ctx_rx) {
2401                 tfm = crypto_aead_tfm(sw_ctx_rx->aead_recv);
2402
2403                 if (crypto_info->version == TLS_1_3_VERSION)
2404                         sw_ctx_rx->async_capable = 0;
2405                 else
2406                         sw_ctx_rx->async_capable =
2407                                 !!(tfm->__crt_alg->cra_flags &
2408                                    CRYPTO_ALG_ASYNC);
2409
2410                 /* Set up strparser */
2411                 memset(&cb, 0, sizeof(cb));
2412                 cb.rcv_msg = tls_queue;
2413                 cb.parse_msg = tls_read_size;
2414
2415                 strp_init(&sw_ctx_rx->strp, sk, &cb);
2416         }
2417
2418         goto out;
2419
2420 free_aead:
2421         crypto_free_aead(*aead);
2422         *aead = NULL;
2423 free_rec_seq:
2424         kfree(cctx->rec_seq);
2425         cctx->rec_seq = NULL;
2426 free_iv:
2427         kfree(cctx->iv);
2428         cctx->iv = NULL;
2429 free_priv:
2430         if (tx) {
2431                 kfree(ctx->priv_ctx_tx);
2432                 ctx->priv_ctx_tx = NULL;
2433         } else {
2434                 kfree(ctx->priv_ctx_rx);
2435                 ctx->priv_ctx_rx = NULL;
2436         }
2437 out:
2438         return rc;
2439 }