1 /*
2 * Copyright (c) 2016-2017, Mellanox Technologies. All rights reserved.
3 * Copyright (c) 2016-2017, Dave Watson <davejwatson@fb.com>. All rights reserved.
4 * Copyright (c) 2016-2017, Lance Chao <lancerchao@fb.com>. All rights reserved.
5 * Copyright (c) 2016, Fridolin Pokorny <fridolin.pokorny@gmail.com>. All rights reserved.
6 * Copyright (c) 2016, Nikos Mavrogiannopoulos <nmav@gnutls.org>. All rights reserved.
7 * Copyright (c) 2018, Covalent IO, Inc. http://covalent.io
8 *
9 * This software is available to you under a choice of one of two
10 * licenses. You may choose to be licensed under the terms of the GNU
11 * General Public License (GPL) Version 2, available from the file
12 * COPYING in the main directory of this source tree, or the
13 * OpenIB.org BSD license below:
14 *
15 * Redistribution and use in source and binary forms, with or
16 * without modification, are permitted provided that the following
17 * conditions are met:
18 *
19 * - Redistributions of source code must retain the above
20 * copyright notice, this list of conditions and the following
21 * disclaimer.
22 *
23 * - Redistributions in binary form must reproduce the above
24 * copyright notice, this list of conditions and the following
25 * disclaimer in the documentation and/or other materials
26 * provided with the distribution.
27 *
28 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
29 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
30 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
31 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
32 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
33 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
34 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
35 * SOFTWARE.
36 */
37
38 #include <linux/bug.h>
39 #include <linux/sched/signal.h>
40 #include <linux/module.h>
41 #include <linux/splice.h>
42 #include <crypto/aead.h>
43
44 #include <net/strparser.h>
45 #include <net/tls.h>
46
tls_err_abort(struct sock * sk,int err)47 noinline void tls_err_abort(struct sock *sk, int err)
48 {
49 WARN_ON_ONCE(err >= 0);
50 /* sk->sk_err should contain a positive error code. */
51 sk->sk_err = -err;
52 sk->sk_error_report(sk);
53 }
54
__skb_nsg(struct sk_buff * skb,int offset,int len,unsigned int recursion_level)55 static int __skb_nsg(struct sk_buff *skb, int offset, int len,
56 unsigned int recursion_level)
57 {
58 int start = skb_headlen(skb);
59 int i, chunk = start - offset;
60 struct sk_buff *frag_iter;
61 int elt = 0;
62
63 if (unlikely(recursion_level >= 24))
64 return -EMSGSIZE;
65
66 if (chunk > 0) {
67 if (chunk > len)
68 chunk = len;
69 elt++;
70 len -= chunk;
71 if (len == 0)
72 return elt;
73 offset += chunk;
74 }
75
76 for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
77 int end;
78
79 WARN_ON(start > offset + len);
80
81 end = start + skb_frag_size(&skb_shinfo(skb)->frags[i]);
82 chunk = end - offset;
83 if (chunk > 0) {
84 if (chunk > len)
85 chunk = len;
86 elt++;
87 len -= chunk;
88 if (len == 0)
89 return elt;
90 offset += chunk;
91 }
92 start = end;
93 }
94
95 if (unlikely(skb_has_frag_list(skb))) {
96 skb_walk_frags(skb, frag_iter) {
97 int end, ret;
98
99 WARN_ON(start > offset + len);
100
101 end = start + frag_iter->len;
102 chunk = end - offset;
103 if (chunk > 0) {
104 if (chunk > len)
105 chunk = len;
106 ret = __skb_nsg(frag_iter, offset - start, chunk,
107 recursion_level + 1);
108 if (unlikely(ret < 0))
109 return ret;
110 elt += ret;
111 len -= chunk;
112 if (len == 0)
113 return elt;
114 offset += chunk;
115 }
116 start = end;
117 }
118 }
119 BUG_ON(len);
120 return elt;
121 }
122
123 /* Return the number of scatterlist elements required to completely map the
124 * skb, or -EMSGSIZE if the recursion depth is exceeded.
125 */
skb_nsg(struct sk_buff * skb,int offset,int len)126 static int skb_nsg(struct sk_buff *skb, int offset, int len)
127 {
128 return __skb_nsg(skb, offset, len, 0);
129 }
130
padding_length(struct tls_sw_context_rx * ctx,struct tls_prot_info * prot,struct sk_buff * skb)131 static int padding_length(struct tls_sw_context_rx *ctx,
132 struct tls_prot_info *prot, struct sk_buff *skb)
133 {
134 struct strp_msg *rxm = strp_msg(skb);
135 int sub = 0;
136
137 /* Determine zero-padding length */
138 if (prot->version == TLS_1_3_VERSION) {
139 char content_type = 0;
140 int err;
141 int back = 17;
142
143 while (content_type == 0) {
144 if (back > rxm->full_len - prot->prepend_size)
145 return -EBADMSG;
146 err = skb_copy_bits(skb,
147 rxm->offset + rxm->full_len - back,
148 &content_type, 1);
149 if (err)
150 return err;
151 if (content_type)
152 break;
153 sub++;
154 back++;
155 }
156 ctx->control = content_type;
157 }
158 return sub;
159 }
160
tls_decrypt_done(struct crypto_async_request * req,int err)161 static void tls_decrypt_done(struct crypto_async_request *req, int err)
162 {
163 struct aead_request *aead_req = (struct aead_request *)req;
164 struct scatterlist *sgout = aead_req->dst;
165 struct scatterlist *sgin = aead_req->src;
166 struct tls_sw_context_rx *ctx;
167 struct tls_context *tls_ctx;
168 struct tls_prot_info *prot;
169 struct scatterlist *sg;
170 struct sk_buff *skb;
171 unsigned int pages;
172 int pending;
173
174 skb = (struct sk_buff *)req->data;
175 tls_ctx = tls_get_ctx(skb->sk);
176 ctx = tls_sw_ctx_rx(tls_ctx);
177 prot = &tls_ctx->prot_info;
178
179 /* Propagate if there was an err */
180 if (err) {
181 if (err == -EBADMSG)
182 TLS_INC_STATS(sock_net(skb->sk),
183 LINUX_MIB_TLSDECRYPTERROR);
184 ctx->async_wait.err = err;
185 tls_err_abort(skb->sk, err);
186 } else {
187 struct strp_msg *rxm = strp_msg(skb);
188 int pad;
189
190 pad = padding_length(ctx, prot, skb);
191 if (pad < 0) {
192 ctx->async_wait.err = pad;
193 tls_err_abort(skb->sk, pad);
194 } else {
195 rxm->full_len -= pad;
196 rxm->offset += prot->prepend_size;
197 rxm->full_len -= prot->overhead_size;
198 }
199 }
200
201 /* After using skb->sk to propagate sk through crypto async callback
202 * we need to NULL it again.
203 */
204 skb->sk = NULL;
205
206
207 /* Free the destination pages if skb was not decrypted inplace */
208 if (sgout != sgin) {
209 /* Skip the first S/G entry as it points to AAD */
210 for_each_sg(sg_next(sgout), sg, UINT_MAX, pages) {
211 if (!sg)
212 break;
213 put_page(sg_page(sg));
214 }
215 }
216
217 kfree(aead_req);
218
219 spin_lock_bh(&ctx->decrypt_compl_lock);
220 pending = atomic_dec_return(&ctx->decrypt_pending);
221
222 if (!pending && ctx->async_notify)
223 complete(&ctx->async_wait.completion);
224 spin_unlock_bh(&ctx->decrypt_compl_lock);
225 }
226
tls_do_decryption(struct sock * sk,struct sk_buff * skb,struct scatterlist * sgin,struct scatterlist * sgout,char * iv_recv,size_t data_len,struct aead_request * aead_req,bool async)227 static int tls_do_decryption(struct sock *sk,
228 struct sk_buff *skb,
229 struct scatterlist *sgin,
230 struct scatterlist *sgout,
231 char *iv_recv,
232 size_t data_len,
233 struct aead_request *aead_req,
234 bool async)
235 {
236 struct tls_context *tls_ctx = tls_get_ctx(sk);
237 struct tls_prot_info *prot = &tls_ctx->prot_info;
238 struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
239 int ret;
240
241 aead_request_set_tfm(aead_req, ctx->aead_recv);
242 aead_request_set_ad(aead_req, prot->aad_size);
243 aead_request_set_crypt(aead_req, sgin, sgout,
244 data_len + prot->tag_size,
245 (u8 *)iv_recv);
246
247 if (async) {
248 /* Using skb->sk to push sk through to crypto async callback
249 * handler. This allows propagating errors up to the socket
250 * if needed. It _must_ be cleared in the async handler
251 * before consume_skb is called. We _know_ skb->sk is NULL
252 * because it is a clone from strparser.
253 */
254 skb->sk = sk;
255 aead_request_set_callback(aead_req,
256 CRYPTO_TFM_REQ_MAY_BACKLOG,
257 tls_decrypt_done, skb);
258 atomic_inc(&ctx->decrypt_pending);
259 } else {
260 aead_request_set_callback(aead_req,
261 CRYPTO_TFM_REQ_MAY_BACKLOG,
262 crypto_req_done, &ctx->async_wait);
263 }
264
265 ret = crypto_aead_decrypt(aead_req);
266 if (ret == -EINPROGRESS) {
267 if (async)
268 return ret;
269
270 ret = crypto_wait_req(ret, &ctx->async_wait);
271 }
272
273 if (async)
274 atomic_dec(&ctx->decrypt_pending);
275
276 return ret;
277 }
278
tls_trim_both_msgs(struct sock * sk,int target_size)279 static void tls_trim_both_msgs(struct sock *sk, int target_size)
280 {
281 struct tls_context *tls_ctx = tls_get_ctx(sk);
282 struct tls_prot_info *prot = &tls_ctx->prot_info;
283 struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
284 struct tls_rec *rec = ctx->open_rec;
285
286 sk_msg_trim(sk, &rec->msg_plaintext, target_size);
287 if (target_size > 0)
288 target_size += prot->overhead_size;
289 sk_msg_trim(sk, &rec->msg_encrypted, target_size);
290 }
291
tls_alloc_encrypted_msg(struct sock * sk,int len)292 static int tls_alloc_encrypted_msg(struct sock *sk, int len)
293 {
294 struct tls_context *tls_ctx = tls_get_ctx(sk);
295 struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
296 struct tls_rec *rec = ctx->open_rec;
297 struct sk_msg *msg_en = &rec->msg_encrypted;
298
299 return sk_msg_alloc(sk, msg_en, len, 0);
300 }
301
tls_clone_plaintext_msg(struct sock * sk,int required)302 static int tls_clone_plaintext_msg(struct sock *sk, int required)
303 {
304 struct tls_context *tls_ctx = tls_get_ctx(sk);
305 struct tls_prot_info *prot = &tls_ctx->prot_info;
306 struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
307 struct tls_rec *rec = ctx->open_rec;
308 struct sk_msg *msg_pl = &rec->msg_plaintext;
309 struct sk_msg *msg_en = &rec->msg_encrypted;
310 int skip, len;
311
312 /* We add page references worth len bytes from encrypted sg
313 * at the end of plaintext sg. It is guaranteed that msg_en
314 * has enough required room (ensured by caller).
315 */
316 len = required - msg_pl->sg.size;
317
318 /* Skip initial bytes in msg_en's data to be able to use
319 * same offset of both plain and encrypted data.
320 */
321 skip = prot->prepend_size + msg_pl->sg.size;
322
323 return sk_msg_clone(sk, msg_pl, msg_en, skip, len);
324 }
325
tls_get_rec(struct sock * sk)326 static struct tls_rec *tls_get_rec(struct sock *sk)
327 {
328 struct tls_context *tls_ctx = tls_get_ctx(sk);
329 struct tls_prot_info *prot = &tls_ctx->prot_info;
330 struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
331 struct sk_msg *msg_pl, *msg_en;
332 struct tls_rec *rec;
333 int mem_size;
334
335 mem_size = sizeof(struct tls_rec) + crypto_aead_reqsize(ctx->aead_send);
336
337 rec = kzalloc(mem_size, sk->sk_allocation);
338 if (!rec)
339 return NULL;
340
341 msg_pl = &rec->msg_plaintext;
342 msg_en = &rec->msg_encrypted;
343
344 sk_msg_init(msg_pl);
345 sk_msg_init(msg_en);
346
347 sg_init_table(rec->sg_aead_in, 2);
348 sg_set_buf(&rec->sg_aead_in[0], rec->aad_space, prot->aad_size);
349 sg_unmark_end(&rec->sg_aead_in[1]);
350
351 sg_init_table(rec->sg_aead_out, 2);
352 sg_set_buf(&rec->sg_aead_out[0], rec->aad_space, prot->aad_size);
353 sg_unmark_end(&rec->sg_aead_out[1]);
354
355 return rec;
356 }
357
tls_free_rec(struct sock * sk,struct tls_rec * rec)358 static void tls_free_rec(struct sock *sk, struct tls_rec *rec)
359 {
360 sk_msg_free(sk, &rec->msg_encrypted);
361 sk_msg_free(sk, &rec->msg_plaintext);
362 kfree(rec);
363 }
364
tls_free_open_rec(struct sock * sk)365 static void tls_free_open_rec(struct sock *sk)
366 {
367 struct tls_context *tls_ctx = tls_get_ctx(sk);
368 struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
369 struct tls_rec *rec = ctx->open_rec;
370
371 if (rec) {
372 tls_free_rec(sk, rec);
373 ctx->open_rec = NULL;
374 }
375 }
376
tls_tx_records(struct sock * sk,int flags)377 int tls_tx_records(struct sock *sk, int flags)
378 {
379 struct tls_context *tls_ctx = tls_get_ctx(sk);
380 struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
381 struct tls_rec *rec, *tmp;
382 struct sk_msg *msg_en;
383 int tx_flags, rc = 0;
384
385 if (tls_is_partially_sent_record(tls_ctx)) {
386 rec = list_first_entry(&ctx->tx_list,
387 struct tls_rec, list);
388
389 if (flags == -1)
390 tx_flags = rec->tx_flags;
391 else
392 tx_flags = flags;
393
394 rc = tls_push_partial_record(sk, tls_ctx, tx_flags);
395 if (rc)
396 goto tx_err;
397
398 /* Full record has been transmitted.
399 * Remove the head of tx_list
400 */
401 list_del(&rec->list);
402 sk_msg_free(sk, &rec->msg_plaintext);
403 kfree(rec);
404 }
405
406 /* Tx all ready records */
407 list_for_each_entry_safe(rec, tmp, &ctx->tx_list, list) {
408 if (READ_ONCE(rec->tx_ready)) {
409 if (flags == -1)
410 tx_flags = rec->tx_flags;
411 else
412 tx_flags = flags;
413
414 msg_en = &rec->msg_encrypted;
415 rc = tls_push_sg(sk, tls_ctx,
416 &msg_en->sg.data[msg_en->sg.curr],
417 0, tx_flags);
418 if (rc)
419 goto tx_err;
420
421 list_del(&rec->list);
422 sk_msg_free(sk, &rec->msg_plaintext);
423 kfree(rec);
424 } else {
425 break;
426 }
427 }
428
429 tx_err:
430 if (rc < 0 && rc != -EAGAIN)
431 tls_err_abort(sk, -EBADMSG);
432
433 return rc;
434 }
435
tls_encrypt_done(struct crypto_async_request * req,int err)436 static void tls_encrypt_done(struct crypto_async_request *req, int err)
437 {
438 struct aead_request *aead_req = (struct aead_request *)req;
439 struct sock *sk = req->data;
440 struct tls_context *tls_ctx = tls_get_ctx(sk);
441 struct tls_prot_info *prot = &tls_ctx->prot_info;
442 struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
443 struct scatterlist *sge;
444 struct sk_msg *msg_en;
445 struct tls_rec *rec;
446 bool ready = false;
447 int pending;
448
449 rec = container_of(aead_req, struct tls_rec, aead_req);
450 msg_en = &rec->msg_encrypted;
451
452 sge = sk_msg_elem(msg_en, msg_en->sg.curr);
453 sge->offset -= prot->prepend_size;
454 sge->length += prot->prepend_size;
455
456 /* Check if error is previously set on socket */
457 if (err || sk->sk_err) {
458 rec = NULL;
459
460 /* If err is already set on socket, return the same code */
461 if (sk->sk_err) {
462 ctx->async_wait.err = -sk->sk_err;
463 } else {
464 ctx->async_wait.err = err;
465 tls_err_abort(sk, err);
466 }
467 }
468
469 if (rec) {
470 struct tls_rec *first_rec;
471
472 /* Mark the record as ready for transmission */
473 smp_store_mb(rec->tx_ready, true);
474
475 /* If received record is at head of tx_list, schedule tx */
476 first_rec = list_first_entry(&ctx->tx_list,
477 struct tls_rec, list);
478 if (rec == first_rec)
479 ready = true;
480 }
481
482 spin_lock_bh(&ctx->encrypt_compl_lock);
483 pending = atomic_dec_return(&ctx->encrypt_pending);
484
485 if (!pending && ctx->async_notify)
486 complete(&ctx->async_wait.completion);
487 spin_unlock_bh(&ctx->encrypt_compl_lock);
488
489 if (!ready)
490 return;
491
492 /* Schedule the transmission */
493 if (!test_and_set_bit(BIT_TX_SCHEDULED, &ctx->tx_bitmask))
494 schedule_delayed_work(&ctx->tx_work.work, 1);
495 }
496
tls_do_encryption(struct sock * sk,struct tls_context * tls_ctx,struct tls_sw_context_tx * ctx,struct aead_request * aead_req,size_t data_len,u32 start)497 static int tls_do_encryption(struct sock *sk,
498 struct tls_context *tls_ctx,
499 struct tls_sw_context_tx *ctx,
500 struct aead_request *aead_req,
501 size_t data_len, u32 start)
502 {
503 struct tls_prot_info *prot = &tls_ctx->prot_info;
504 struct tls_rec *rec = ctx->open_rec;
505 struct sk_msg *msg_en = &rec->msg_encrypted;
506 struct scatterlist *sge = sk_msg_elem(msg_en, start);
507 int rc, iv_offset = 0;
508
509 /* For CCM based ciphers, first byte of IV is a constant */
510 if (prot->cipher_type == TLS_CIPHER_AES_CCM_128) {
511 rec->iv_data[0] = TLS_AES_CCM_IV_B0_BYTE;
512 iv_offset = 1;
513 }
514
515 memcpy(&rec->iv_data[iv_offset], tls_ctx->tx.iv,
516 prot->iv_size + prot->salt_size);
517
518 xor_iv_with_seq(prot->version, rec->iv_data + iv_offset, tls_ctx->tx.rec_seq);
519
520 sge->offset += prot->prepend_size;
521 sge->length -= prot->prepend_size;
522
523 msg_en->sg.curr = start;
524
525 aead_request_set_tfm(aead_req, ctx->aead_send);
526 aead_request_set_ad(aead_req, prot->aad_size);
527 aead_request_set_crypt(aead_req, rec->sg_aead_in,
528 rec->sg_aead_out,
529 data_len, rec->iv_data);
530
531 aead_request_set_callback(aead_req, CRYPTO_TFM_REQ_MAY_BACKLOG,
532 tls_encrypt_done, sk);
533
534 /* Add the record in tx_list */
535 list_add_tail((struct list_head *)&rec->list, &ctx->tx_list);
536 atomic_inc(&ctx->encrypt_pending);
537
538 rc = crypto_aead_encrypt(aead_req);
539 if (!rc || rc != -EINPROGRESS) {
540 atomic_dec(&ctx->encrypt_pending);
541 sge->offset -= prot->prepend_size;
542 sge->length += prot->prepend_size;
543 }
544
545 if (!rc) {
546 WRITE_ONCE(rec->tx_ready, true);
547 } else if (rc != -EINPROGRESS) {
548 list_del(&rec->list);
549 return rc;
550 }
551
552 /* Unhook the record from context if encryption is not failure */
553 ctx->open_rec = NULL;
554 tls_advance_record_sn(sk, prot, &tls_ctx->tx);
555 return rc;
556 }
557
tls_split_open_record(struct sock * sk,struct tls_rec * from,struct tls_rec ** to,struct sk_msg * msg_opl,struct sk_msg * msg_oen,u32 split_point,u32 tx_overhead_size,u32 * orig_end)558 static int tls_split_open_record(struct sock *sk, struct tls_rec *from,
559 struct tls_rec **to, struct sk_msg *msg_opl,
560 struct sk_msg *msg_oen, u32 split_point,
561 u32 tx_overhead_size, u32 *orig_end)
562 {
563 u32 i, j, bytes = 0, apply = msg_opl->apply_bytes;
564 struct scatterlist *sge, *osge, *nsge;
565 u32 orig_size = msg_opl->sg.size;
566 struct scatterlist tmp = { };
567 struct sk_msg *msg_npl;
568 struct tls_rec *new;
569 int ret;
570
571 new = tls_get_rec(sk);
572 if (!new)
573 return -ENOMEM;
574 ret = sk_msg_alloc(sk, &new->msg_encrypted, msg_opl->sg.size +
575 tx_overhead_size, 0);
576 if (ret < 0) {
577 tls_free_rec(sk, new);
578 return ret;
579 }
580
581 *orig_end = msg_opl->sg.end;
582 i = msg_opl->sg.start;
583 sge = sk_msg_elem(msg_opl, i);
584 while (apply && sge->length) {
585 if (sge->length > apply) {
586 u32 len = sge->length - apply;
587
588 get_page(sg_page(sge));
589 sg_set_page(&tmp, sg_page(sge), len,
590 sge->offset + apply);
591 sge->length = apply;
592 bytes += apply;
593 apply = 0;
594 } else {
595 apply -= sge->length;
596 bytes += sge->length;
597 }
598
599 sk_msg_iter_var_next(i);
600 if (i == msg_opl->sg.end)
601 break;
602 sge = sk_msg_elem(msg_opl, i);
603 }
604
605 msg_opl->sg.end = i;
606 msg_opl->sg.curr = i;
607 msg_opl->sg.copybreak = 0;
608 msg_opl->apply_bytes = 0;
609 msg_opl->sg.size = bytes;
610
611 msg_npl = &new->msg_plaintext;
612 msg_npl->apply_bytes = apply;
613 msg_npl->sg.size = orig_size - bytes;
614
615 j = msg_npl->sg.start;
616 nsge = sk_msg_elem(msg_npl, j);
617 if (tmp.length) {
618 memcpy(nsge, &tmp, sizeof(*nsge));
619 sk_msg_iter_var_next(j);
620 nsge = sk_msg_elem(msg_npl, j);
621 }
622
623 osge = sk_msg_elem(msg_opl, i);
624 while (osge->length) {
625 memcpy(nsge, osge, sizeof(*nsge));
626 sg_unmark_end(nsge);
627 sk_msg_iter_var_next(i);
628 sk_msg_iter_var_next(j);
629 if (i == *orig_end)
630 break;
631 osge = sk_msg_elem(msg_opl, i);
632 nsge = sk_msg_elem(msg_npl, j);
633 }
634
635 msg_npl->sg.end = j;
636 msg_npl->sg.curr = j;
637 msg_npl->sg.copybreak = 0;
638
639 *to = new;
640 return 0;
641 }
642
tls_merge_open_record(struct sock * sk,struct tls_rec * to,struct tls_rec * from,u32 orig_end)643 static void tls_merge_open_record(struct sock *sk, struct tls_rec *to,
644 struct tls_rec *from, u32 orig_end)
645 {
646 struct sk_msg *msg_npl = &from->msg_plaintext;
647 struct sk_msg *msg_opl = &to->msg_plaintext;
648 struct scatterlist *osge, *nsge;
649 u32 i, j;
650
651 i = msg_opl->sg.end;
652 sk_msg_iter_var_prev(i);
653 j = msg_npl->sg.start;
654
655 osge = sk_msg_elem(msg_opl, i);
656 nsge = sk_msg_elem(msg_npl, j);
657
658 if (sg_page(osge) == sg_page(nsge) &&
659 osge->offset + osge->length == nsge->offset) {
660 osge->length += nsge->length;
661 put_page(sg_page(nsge));
662 }
663
664 msg_opl->sg.end = orig_end;
665 msg_opl->sg.curr = orig_end;
666 msg_opl->sg.copybreak = 0;
667 msg_opl->apply_bytes = msg_opl->sg.size + msg_npl->sg.size;
668 msg_opl->sg.size += msg_npl->sg.size;
669
670 sk_msg_free(sk, &to->msg_encrypted);
671 sk_msg_xfer_full(&to->msg_encrypted, &from->msg_encrypted);
672
673 kfree(from);
674 }
675
tls_push_record(struct sock * sk,int flags,unsigned char record_type)676 static int tls_push_record(struct sock *sk, int flags,
677 unsigned char record_type)
678 {
679 struct tls_context *tls_ctx = tls_get_ctx(sk);
680 struct tls_prot_info *prot = &tls_ctx->prot_info;
681 struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
682 struct tls_rec *rec = ctx->open_rec, *tmp = NULL;
683 u32 i, split_point, orig_end;
684 struct sk_msg *msg_pl, *msg_en;
685 struct aead_request *req;
686 bool split;
687 int rc;
688
689 if (!rec)
690 return 0;
691
692 msg_pl = &rec->msg_plaintext;
693 msg_en = &rec->msg_encrypted;
694
695 split_point = msg_pl->apply_bytes;
696 split = split_point && split_point < msg_pl->sg.size;
697 if (unlikely((!split &&
698 msg_pl->sg.size +
699 prot->overhead_size > msg_en->sg.size) ||
700 (split &&
701 split_point +
702 prot->overhead_size > msg_en->sg.size))) {
703 split = true;
704 split_point = msg_en->sg.size;
705 }
706 if (split) {
707 rc = tls_split_open_record(sk, rec, &tmp, msg_pl, msg_en,
708 split_point, prot->overhead_size,
709 &orig_end);
710 if (rc < 0)
711 return rc;
712 /* This can happen if above tls_split_open_record allocates
713 * a single large encryption buffer instead of two smaller
714 * ones. In this case adjust pointers and continue without
715 * split.
716 */
717 if (!msg_pl->sg.size) {
718 tls_merge_open_record(sk, rec, tmp, orig_end);
719 msg_pl = &rec->msg_plaintext;
720 msg_en = &rec->msg_encrypted;
721 split = false;
722 }
723 sk_msg_trim(sk, msg_en, msg_pl->sg.size +
724 prot->overhead_size);
725 }
726
727 rec->tx_flags = flags;
728 req = &rec->aead_req;
729
730 i = msg_pl->sg.end;
731 sk_msg_iter_var_prev(i);
732
733 rec->content_type = record_type;
734 if (prot->version == TLS_1_3_VERSION) {
735 /* Add content type to end of message. No padding added */
736 sg_set_buf(&rec->sg_content_type, &rec->content_type, 1);
737 sg_mark_end(&rec->sg_content_type);
738 sg_chain(msg_pl->sg.data, msg_pl->sg.end + 1,
739 &rec->sg_content_type);
740 } else {
741 sg_mark_end(sk_msg_elem(msg_pl, i));
742 }
743
744 if (msg_pl->sg.end < msg_pl->sg.start) {
745 sg_chain(&msg_pl->sg.data[msg_pl->sg.start],
746 MAX_SKB_FRAGS - msg_pl->sg.start + 1,
747 msg_pl->sg.data);
748 }
749
750 i = msg_pl->sg.start;
751 sg_chain(rec->sg_aead_in, 2, &msg_pl->sg.data[i]);
752
753 i = msg_en->sg.end;
754 sk_msg_iter_var_prev(i);
755 sg_mark_end(sk_msg_elem(msg_en, i));
756
757 i = msg_en->sg.start;
758 sg_chain(rec->sg_aead_out, 2, &msg_en->sg.data[i]);
759
760 tls_make_aad(rec->aad_space, msg_pl->sg.size + prot->tail_size,
761 tls_ctx->tx.rec_seq, prot->rec_seq_size,
762 record_type, prot->version);
763
764 tls_fill_prepend(tls_ctx,
765 page_address(sg_page(&msg_en->sg.data[i])) +
766 msg_en->sg.data[i].offset,
767 msg_pl->sg.size + prot->tail_size,
768 record_type, prot->version);
769
770 tls_ctx->pending_open_record_frags = false;
771
772 rc = tls_do_encryption(sk, tls_ctx, ctx, req,
773 msg_pl->sg.size + prot->tail_size, i);
774 if (rc < 0) {
775 if (rc != -EINPROGRESS) {
776 tls_err_abort(sk, -EBADMSG);
777 if (split) {
778 tls_ctx->pending_open_record_frags = true;
779 tls_merge_open_record(sk, rec, tmp, orig_end);
780 }
781 }
782 ctx->async_capable = 1;
783 return rc;
784 } else if (split) {
785 msg_pl = &tmp->msg_plaintext;
786 msg_en = &tmp->msg_encrypted;
787 sk_msg_trim(sk, msg_en, msg_pl->sg.size + prot->overhead_size);
788 tls_ctx->pending_open_record_frags = true;
789 ctx->open_rec = tmp;
790 }
791
792 return tls_tx_records(sk, flags);
793 }
794
bpf_exec_tx_verdict(struct sk_msg * msg,struct sock * sk,bool full_record,u8 record_type,ssize_t * copied,int flags)795 static int bpf_exec_tx_verdict(struct sk_msg *msg, struct sock *sk,
796 bool full_record, u8 record_type,
797 ssize_t *copied, int flags)
798 {
799 struct tls_context *tls_ctx = tls_get_ctx(sk);
800 struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
801 struct sk_msg msg_redir = { };
802 struct sk_psock *psock;
803 struct sock *sk_redir;
804 struct tls_rec *rec;
805 bool enospc, policy;
806 int err = 0, send;
807 u32 delta = 0;
808
809 policy = !(flags & MSG_SENDPAGE_NOPOLICY);
810 psock = sk_psock_get(sk);
811 if (!psock || !policy) {
812 err = tls_push_record(sk, flags, record_type);
813 if (err && sk->sk_err == EBADMSG) {
814 *copied -= sk_msg_free(sk, msg);
815 tls_free_open_rec(sk);
816 err = -sk->sk_err;
817 }
818 if (psock)
819 sk_psock_put(sk, psock);
820 return err;
821 }
822 more_data:
823 enospc = sk_msg_full(msg);
824 if (psock->eval == __SK_NONE) {
825 delta = msg->sg.size;
826 psock->eval = sk_psock_msg_verdict(sk, psock, msg);
827 delta -= msg->sg.size;
828 }
829 if (msg->cork_bytes && msg->cork_bytes > msg->sg.size &&
830 !enospc && !full_record) {
831 err = -ENOSPC;
832 goto out_err;
833 }
834 msg->cork_bytes = 0;
835 send = msg->sg.size;
836 if (msg->apply_bytes && msg->apply_bytes < send)
837 send = msg->apply_bytes;
838
839 switch (psock->eval) {
840 case __SK_PASS:
841 err = tls_push_record(sk, flags, record_type);
842 if (err && sk->sk_err == EBADMSG) {
843 *copied -= sk_msg_free(sk, msg);
844 tls_free_open_rec(sk);
845 err = -sk->sk_err;
846 goto out_err;
847 }
848 break;
849 case __SK_REDIRECT:
850 sk_redir = psock->sk_redir;
851 memcpy(&msg_redir, msg, sizeof(*msg));
852 if (msg->apply_bytes < send)
853 msg->apply_bytes = 0;
854 else
855 msg->apply_bytes -= send;
856 sk_msg_return_zero(sk, msg, send);
857 msg->sg.size -= send;
858 release_sock(sk);
859 err = tcp_bpf_sendmsg_redir(sk_redir, &msg_redir, send, flags);
860 lock_sock(sk);
861 if (err < 0) {
862 *copied -= sk_msg_free_nocharge(sk, &msg_redir);
863 msg->sg.size = 0;
864 }
865 if (msg->sg.size == 0)
866 tls_free_open_rec(sk);
867 break;
868 case __SK_DROP:
869 default:
870 sk_msg_free_partial(sk, msg, send);
871 if (msg->apply_bytes < send)
872 msg->apply_bytes = 0;
873 else
874 msg->apply_bytes -= send;
875 if (msg->sg.size == 0)
876 tls_free_open_rec(sk);
877 *copied -= (send + delta);
878 err = -EACCES;
879 }
880
881 if (likely(!err)) {
882 bool reset_eval = !ctx->open_rec;
883
884 rec = ctx->open_rec;
885 if (rec) {
886 msg = &rec->msg_plaintext;
887 if (!msg->apply_bytes)
888 reset_eval = true;
889 }
890 if (reset_eval) {
891 psock->eval = __SK_NONE;
892 if (psock->sk_redir) {
893 sock_put(psock->sk_redir);
894 psock->sk_redir = NULL;
895 }
896 }
897 if (rec)
898 goto more_data;
899 }
900 out_err:
901 sk_psock_put(sk, psock);
902 return err;
903 }
904
tls_sw_push_pending_record(struct sock * sk,int flags)905 static int tls_sw_push_pending_record(struct sock *sk, int flags)
906 {
907 struct tls_context *tls_ctx = tls_get_ctx(sk);
908 struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
909 struct tls_rec *rec = ctx->open_rec;
910 struct sk_msg *msg_pl;
911 size_t copied;
912
913 if (!rec)
914 return 0;
915
916 msg_pl = &rec->msg_plaintext;
917 copied = msg_pl->sg.size;
918 if (!copied)
919 return 0;
920
921 return bpf_exec_tx_verdict(msg_pl, sk, true, TLS_RECORD_TYPE_DATA,
922 &copied, flags);
923 }
924
tls_sw_sendmsg(struct sock * sk,struct msghdr * msg,size_t size)925 int tls_sw_sendmsg(struct sock *sk, struct msghdr *msg, size_t size)
926 {
927 long timeo = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT);
928 struct tls_context *tls_ctx = tls_get_ctx(sk);
929 struct tls_prot_info *prot = &tls_ctx->prot_info;
930 struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
931 bool async_capable = ctx->async_capable;
932 unsigned char record_type = TLS_RECORD_TYPE_DATA;
933 bool is_kvec = iov_iter_is_kvec(&msg->msg_iter);
934 bool eor = !(msg->msg_flags & MSG_MORE);
935 size_t try_to_copy;
936 ssize_t copied = 0;
937 struct sk_msg *msg_pl, *msg_en;
938 struct tls_rec *rec;
939 int required_size;
940 int num_async = 0;
941 bool full_record;
942 int record_room;
943 int num_zc = 0;
944 int orig_size;
945 int ret = 0;
946 int pending;
947
948 if (msg->msg_flags & ~(MSG_MORE | MSG_DONTWAIT | MSG_NOSIGNAL |
949 MSG_CMSG_COMPAT))
950 return -EOPNOTSUPP;
951
952 mutex_lock(&tls_ctx->tx_lock);
953 lock_sock(sk);
954
955 if (unlikely(msg->msg_controllen)) {
956 ret = tls_proccess_cmsg(sk, msg, &record_type);
957 if (ret) {
958 if (ret == -EINPROGRESS)
959 num_async++;
960 else if (ret != -EAGAIN)
961 goto send_end;
962 }
963 }
964
965 while (msg_data_left(msg)) {
966 if (sk->sk_err) {
967 ret = -sk->sk_err;
968 goto send_end;
969 }
970
971 if (ctx->open_rec)
972 rec = ctx->open_rec;
973 else
974 rec = ctx->open_rec = tls_get_rec(sk);
975 if (!rec) {
976 ret = -ENOMEM;
977 goto send_end;
978 }
979
980 msg_pl = &rec->msg_plaintext;
981 msg_en = &rec->msg_encrypted;
982
983 orig_size = msg_pl->sg.size;
984 full_record = false;
985 try_to_copy = msg_data_left(msg);
986 record_room = TLS_MAX_PAYLOAD_SIZE - msg_pl->sg.size;
987 if (try_to_copy >= record_room) {
988 try_to_copy = record_room;
989 full_record = true;
990 }
991
992 required_size = msg_pl->sg.size + try_to_copy +
993 prot->overhead_size;
994
995 if (!sk_stream_memory_free(sk))
996 goto wait_for_sndbuf;
997
998 alloc_encrypted:
999 ret = tls_alloc_encrypted_msg(sk, required_size);
1000 if (ret) {
1001 if (ret != -ENOSPC)
1002 goto wait_for_memory;
1003
1004 /* Adjust try_to_copy according to the amount that was
1005 * actually allocated. The difference is due
1006 * to max sg elements limit
1007 */
1008 try_to_copy -= required_size - msg_en->sg.size;
1009 full_record = true;
1010 }
1011
1012 if (!is_kvec && (full_record || eor) && !async_capable) {
1013 u32 first = msg_pl->sg.end;
1014
1015 ret = sk_msg_zerocopy_from_iter(sk, &msg->msg_iter,
1016 msg_pl, try_to_copy);
1017 if (ret)
1018 goto fallback_to_reg_send;
1019
1020 num_zc++;
1021 copied += try_to_copy;
1022
1023 sk_msg_sg_copy_set(msg_pl, first);
1024 ret = bpf_exec_tx_verdict(msg_pl, sk, full_record,
1025 record_type, &copied,
1026 msg->msg_flags);
1027 if (ret) {
1028 if (ret == -EINPROGRESS)
1029 num_async++;
1030 else if (ret == -ENOMEM)
1031 goto wait_for_memory;
1032 else if (ctx->open_rec && ret == -ENOSPC)
1033 goto rollback_iter;
1034 else if (ret != -EAGAIN)
1035 goto send_end;
1036 }
1037 continue;
1038 rollback_iter:
1039 copied -= try_to_copy;
1040 sk_msg_sg_copy_clear(msg_pl, first);
1041 iov_iter_revert(&msg->msg_iter,
1042 msg_pl->sg.size - orig_size);
1043 fallback_to_reg_send:
1044 sk_msg_trim(sk, msg_pl, orig_size);
1045 }
1046
1047 required_size = msg_pl->sg.size + try_to_copy;
1048
1049 ret = tls_clone_plaintext_msg(sk, required_size);
1050 if (ret) {
1051 if (ret != -ENOSPC)
1052 goto send_end;
1053
1054 /* Adjust try_to_copy according to the amount that was
1055 * actually allocated. The difference is due
1056 * to max sg elements limit
1057 */
1058 try_to_copy -= required_size - msg_pl->sg.size;
1059 full_record = true;
1060 sk_msg_trim(sk, msg_en,
1061 msg_pl->sg.size + prot->overhead_size);
1062 }
1063
1064 if (try_to_copy) {
1065 ret = sk_msg_memcopy_from_iter(sk, &msg->msg_iter,
1066 msg_pl, try_to_copy);
1067 if (ret < 0)
1068 goto trim_sgl;
1069 }
1070
1071 /* Open records defined only if successfully copied, otherwise
1072 * we would trim the sg but not reset the open record frags.
1073 */
1074 tls_ctx->pending_open_record_frags = true;
1075 copied += try_to_copy;
1076 if (full_record || eor) {
1077 ret = bpf_exec_tx_verdict(msg_pl, sk, full_record,
1078 record_type, &copied,
1079 msg->msg_flags);
1080 if (ret) {
1081 if (ret == -EINPROGRESS)
1082 num_async++;
1083 else if (ret == -ENOMEM)
1084 goto wait_for_memory;
1085 else if (ret != -EAGAIN) {
1086 if (ret == -ENOSPC)
1087 ret = 0;
1088 goto send_end;
1089 }
1090 }
1091 }
1092
1093 continue;
1094
1095 wait_for_sndbuf:
1096 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1097 wait_for_memory:
1098 ret = sk_stream_wait_memory(sk, &timeo);
1099 if (ret) {
1100 trim_sgl:
1101 if (ctx->open_rec)
1102 tls_trim_both_msgs(sk, orig_size);
1103 goto send_end;
1104 }
1105
1106 if (ctx->open_rec && msg_en->sg.size < required_size)
1107 goto alloc_encrypted;
1108 }
1109
1110 if (!num_async) {
1111 goto send_end;
1112 } else if (num_zc) {
1113 /* Wait for pending encryptions to get completed */
1114 spin_lock_bh(&ctx->encrypt_compl_lock);
1115 ctx->async_notify = true;
1116
1117 pending = atomic_read(&ctx->encrypt_pending);
1118 spin_unlock_bh(&ctx->encrypt_compl_lock);
1119 if (pending)
1120 crypto_wait_req(-EINPROGRESS, &ctx->async_wait);
1121 else
1122 reinit_completion(&ctx->async_wait.completion);
1123
1124 /* There can be no concurrent accesses, since we have no
1125 * pending encrypt operations
1126 */
1127 WRITE_ONCE(ctx->async_notify, false);
1128
1129 if (ctx->async_wait.err) {
1130 ret = ctx->async_wait.err;
1131 copied = 0;
1132 }
1133 }
1134
1135 /* Transmit if any encryptions have completed */
1136 if (test_and_clear_bit(BIT_TX_SCHEDULED, &ctx->tx_bitmask)) {
1137 cancel_delayed_work(&ctx->tx_work.work);
1138 tls_tx_records(sk, msg->msg_flags);
1139 }
1140
1141 send_end:
1142 ret = sk_stream_error(sk, msg->msg_flags, ret);
1143
1144 release_sock(sk);
1145 mutex_unlock(&tls_ctx->tx_lock);
1146 return copied > 0 ? copied : ret;
1147 }
1148
tls_sw_do_sendpage(struct sock * sk,struct page * page,int offset,size_t size,int flags)1149 static int tls_sw_do_sendpage(struct sock *sk, struct page *page,
1150 int offset, size_t size, int flags)
1151 {
1152 long timeo = sock_sndtimeo(sk, flags & MSG_DONTWAIT);
1153 struct tls_context *tls_ctx = tls_get_ctx(sk);
1154 struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
1155 struct tls_prot_info *prot = &tls_ctx->prot_info;
1156 unsigned char record_type = TLS_RECORD_TYPE_DATA;
1157 struct sk_msg *msg_pl;
1158 struct tls_rec *rec;
1159 int num_async = 0;
1160 ssize_t copied = 0;
1161 bool full_record;
1162 int record_room;
1163 int ret = 0;
1164 bool eor;
1165
1166 eor = !(flags & MSG_SENDPAGE_NOTLAST);
1167 sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);
1168
1169 /* Call the sk_stream functions to manage the sndbuf mem. */
1170 while (size > 0) {
1171 size_t copy, required_size;
1172
1173 if (sk->sk_err) {
1174 ret = -sk->sk_err;
1175 goto sendpage_end;
1176 }
1177
1178 if (ctx->open_rec)
1179 rec = ctx->open_rec;
1180 else
1181 rec = ctx->open_rec = tls_get_rec(sk);
1182 if (!rec) {
1183 ret = -ENOMEM;
1184 goto sendpage_end;
1185 }
1186
1187 msg_pl = &rec->msg_plaintext;
1188
1189 full_record = false;
1190 record_room = TLS_MAX_PAYLOAD_SIZE - msg_pl->sg.size;
1191 copy = size;
1192 if (copy >= record_room) {
1193 copy = record_room;
1194 full_record = true;
1195 }
1196
1197 required_size = msg_pl->sg.size + copy + prot->overhead_size;
1198
1199 if (!sk_stream_memory_free(sk))
1200 goto wait_for_sndbuf;
1201 alloc_payload:
1202 ret = tls_alloc_encrypted_msg(sk, required_size);
1203 if (ret) {
1204 if (ret != -ENOSPC)
1205 goto wait_for_memory;
1206
1207 /* Adjust copy according to the amount that was
1208 * actually allocated. The difference is due
1209 * to max sg elements limit
1210 */
1211 copy -= required_size - msg_pl->sg.size;
1212 full_record = true;
1213 }
1214
1215 sk_msg_page_add(msg_pl, page, copy, offset);
1216 sk_mem_charge(sk, copy);
1217
1218 offset += copy;
1219 size -= copy;
1220 copied += copy;
1221
1222 tls_ctx->pending_open_record_frags = true;
1223 if (full_record || eor || sk_msg_full(msg_pl)) {
1224 ret = bpf_exec_tx_verdict(msg_pl, sk, full_record,
1225 record_type, &copied, flags);
1226 if (ret) {
1227 if (ret == -EINPROGRESS)
1228 num_async++;
1229 else if (ret == -ENOMEM)
1230 goto wait_for_memory;
1231 else if (ret != -EAGAIN) {
1232 if (ret == -ENOSPC)
1233 ret = 0;
1234 goto sendpage_end;
1235 }
1236 }
1237 }
1238 continue;
1239 wait_for_sndbuf:
1240 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1241 wait_for_memory:
1242 ret = sk_stream_wait_memory(sk, &timeo);
1243 if (ret) {
1244 if (ctx->open_rec)
1245 tls_trim_both_msgs(sk, msg_pl->sg.size);
1246 goto sendpage_end;
1247 }
1248
1249 if (ctx->open_rec)
1250 goto alloc_payload;
1251 }
1252
1253 if (num_async) {
1254 /* Transmit if any encryptions have completed */
1255 if (test_and_clear_bit(BIT_TX_SCHEDULED, &ctx->tx_bitmask)) {
1256 cancel_delayed_work(&ctx->tx_work.work);
1257 tls_tx_records(sk, flags);
1258 }
1259 }
1260 sendpage_end:
1261 ret = sk_stream_error(sk, flags, ret);
1262 return copied > 0 ? copied : ret;
1263 }
1264
tls_sw_sendpage_locked(struct sock * sk,struct page * page,int offset,size_t size,int flags)1265 int tls_sw_sendpage_locked(struct sock *sk, struct page *page,
1266 int offset, size_t size, int flags)
1267 {
1268 if (flags & ~(MSG_MORE | MSG_DONTWAIT | MSG_NOSIGNAL |
1269 MSG_SENDPAGE_NOTLAST | MSG_SENDPAGE_NOPOLICY |
1270 MSG_NO_SHARED_FRAGS))
1271 return -EOPNOTSUPP;
1272
1273 return tls_sw_do_sendpage(sk, page, offset, size, flags);
1274 }
1275
tls_sw_sendpage(struct sock * sk,struct page * page,int offset,size_t size,int flags)1276 int tls_sw_sendpage(struct sock *sk, struct page *page,
1277 int offset, size_t size, int flags)
1278 {
1279 struct tls_context *tls_ctx = tls_get_ctx(sk);
1280 int ret;
1281
1282 if (flags & ~(MSG_MORE | MSG_DONTWAIT | MSG_NOSIGNAL |
1283 MSG_SENDPAGE_NOTLAST | MSG_SENDPAGE_NOPOLICY))
1284 return -EOPNOTSUPP;
1285
1286 mutex_lock(&tls_ctx->tx_lock);
1287 lock_sock(sk);
1288 ret = tls_sw_do_sendpage(sk, page, offset, size, flags);
1289 release_sock(sk);
1290 mutex_unlock(&tls_ctx->tx_lock);
1291 return ret;
1292 }
1293
tls_wait_data(struct sock * sk,struct sk_psock * psock,bool nonblock,long timeo,int * err)1294 static struct sk_buff *tls_wait_data(struct sock *sk, struct sk_psock *psock,
1295 bool nonblock, long timeo, int *err)
1296 {
1297 struct tls_context *tls_ctx = tls_get_ctx(sk);
1298 struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
1299 struct sk_buff *skb;
1300 DEFINE_WAIT_FUNC(wait, woken_wake_function);
1301
1302 while (!(skb = ctx->recv_pkt) && sk_psock_queue_empty(psock)) {
1303 if (sk->sk_err) {
1304 *err = sock_error(sk);
1305 return NULL;
1306 }
1307
1308 if (!skb_queue_empty(&sk->sk_receive_queue)) {
1309 __strp_unpause(&ctx->strp);
1310 if (ctx->recv_pkt)
1311 return ctx->recv_pkt;
1312 }
1313
1314 if (sk->sk_shutdown & RCV_SHUTDOWN)
1315 return NULL;
1316
1317 if (sock_flag(sk, SOCK_DONE))
1318 return NULL;
1319
1320 if (nonblock || !timeo) {
1321 *err = -EAGAIN;
1322 return NULL;
1323 }
1324
1325 add_wait_queue(sk_sleep(sk), &wait);
1326 sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk);
1327 sk_wait_event(sk, &timeo,
1328 ctx->recv_pkt != skb ||
1329 !sk_psock_queue_empty(psock),
1330 &wait);
1331 sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk);
1332 remove_wait_queue(sk_sleep(sk), &wait);
1333
1334 /* Handle signals */
1335 if (signal_pending(current)) {
1336 *err = sock_intr_errno(timeo);
1337 return NULL;
1338 }
1339 }
1340
1341 return skb;
1342 }
1343
tls_setup_from_iter(struct sock * sk,struct iov_iter * from,int length,int * pages_used,unsigned int * size_used,struct scatterlist * to,int to_max_pages)1344 static int tls_setup_from_iter(struct sock *sk, struct iov_iter *from,
1345 int length, int *pages_used,
1346 unsigned int *size_used,
1347 struct scatterlist *to,
1348 int to_max_pages)
1349 {
1350 int rc = 0, i = 0, num_elem = *pages_used, maxpages;
1351 struct page *pages[MAX_SKB_FRAGS];
1352 unsigned int size = *size_used;
1353 ssize_t copied, use;
1354 size_t offset;
1355
1356 while (length > 0) {
1357 i = 0;
1358 maxpages = to_max_pages - num_elem;
1359 if (maxpages == 0) {
1360 rc = -EFAULT;
1361 goto out;
1362 }
1363 copied = iov_iter_get_pages(from, pages,
1364 length,
1365 maxpages, &offset);
1366 if (copied <= 0) {
1367 rc = -EFAULT;
1368 goto out;
1369 }
1370
1371 iov_iter_advance(from, copied);
1372
1373 length -= copied;
1374 size += copied;
1375 while (copied) {
1376 use = min_t(int, copied, PAGE_SIZE - offset);
1377
1378 sg_set_page(&to[num_elem],
1379 pages[i], use, offset);
1380 sg_unmark_end(&to[num_elem]);
1381 /* We do not uncharge memory from this API */
1382
1383 offset = 0;
1384 copied -= use;
1385
1386 i++;
1387 num_elem++;
1388 }
1389 }
1390 /* Mark the end in the last sg entry if newly added */
1391 if (num_elem > *pages_used)
1392 sg_mark_end(&to[num_elem - 1]);
1393 out:
1394 if (rc)
1395 iov_iter_revert(from, size - *size_used);
1396 *size_used = size;
1397 *pages_used = num_elem;
1398
1399 return rc;
1400 }
1401
1402 /* This function decrypts the input skb into either out_iov or in out_sg
1403 * or in skb buffers itself. The input parameter 'zc' indicates if
1404 * zero-copy mode needs to be tried or not. With zero-copy mode, either
1405 * out_iov or out_sg must be non-NULL. In case both out_iov and out_sg are
1406 * NULL, then the decryption happens inside skb buffers itself, i.e.
1407 * zero-copy gets disabled and 'zc' is updated.
1408 */
1409
decrypt_internal(struct sock * sk,struct sk_buff * skb,struct iov_iter * out_iov,struct scatterlist * out_sg,int * chunk,bool * zc,bool async)1410 static int decrypt_internal(struct sock *sk, struct sk_buff *skb,
1411 struct iov_iter *out_iov,
1412 struct scatterlist *out_sg,
1413 int *chunk, bool *zc, bool async)
1414 {
1415 struct tls_context *tls_ctx = tls_get_ctx(sk);
1416 struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
1417 struct tls_prot_info *prot = &tls_ctx->prot_info;
1418 struct strp_msg *rxm = strp_msg(skb);
1419 int n_sgin, n_sgout, nsg, mem_size, aead_size, err, pages = 0;
1420 struct aead_request *aead_req;
1421 struct sk_buff *unused;
1422 u8 *aad, *iv, *mem = NULL;
1423 struct scatterlist *sgin = NULL;
1424 struct scatterlist *sgout = NULL;
1425 const int data_len = rxm->full_len - prot->overhead_size +
1426 prot->tail_size;
1427 int iv_offset = 0;
1428
1429 if (*zc && (out_iov || out_sg)) {
1430 if (out_iov)
1431 n_sgout = iov_iter_npages(out_iov, INT_MAX) + 1;
1432 else
1433 n_sgout = sg_nents(out_sg);
1434 n_sgin = skb_nsg(skb, rxm->offset + prot->prepend_size,
1435 rxm->full_len - prot->prepend_size);
1436 } else {
1437 n_sgout = 0;
1438 *zc = false;
1439 n_sgin = skb_cow_data(skb, 0, &unused);
1440 }
1441
1442 if (n_sgin < 1)
1443 return -EBADMSG;
1444
1445 /* Increment to accommodate AAD */
1446 n_sgin = n_sgin + 1;
1447
1448 nsg = n_sgin + n_sgout;
1449
1450 aead_size = sizeof(*aead_req) + crypto_aead_reqsize(ctx->aead_recv);
1451 mem_size = aead_size + (nsg * sizeof(struct scatterlist));
1452 mem_size = mem_size + prot->aad_size;
1453 mem_size = mem_size + crypto_aead_ivsize(ctx->aead_recv);
1454
1455 /* Allocate a single block of memory which contains
1456 * aead_req || sgin[] || sgout[] || aad || iv.
1457 * This order achieves correct alignment for aead_req, sgin, sgout.
1458 */
1459 mem = kmalloc(mem_size, sk->sk_allocation);
1460 if (!mem)
1461 return -ENOMEM;
1462
1463 /* Segment the allocated memory */
1464 aead_req = (struct aead_request *)mem;
1465 sgin = (struct scatterlist *)(mem + aead_size);
1466 sgout = sgin + n_sgin;
1467 aad = (u8 *)(sgout + n_sgout);
1468 iv = aad + prot->aad_size;
1469
1470 /* For CCM based ciphers, first byte of nonce+iv is always '2' */
1471 if (prot->cipher_type == TLS_CIPHER_AES_CCM_128) {
1472 iv[0] = 2;
1473 iv_offset = 1;
1474 }
1475
1476 /* Prepare IV */
1477 err = skb_copy_bits(skb, rxm->offset + TLS_HEADER_SIZE,
1478 iv + iv_offset + prot->salt_size,
1479 prot->iv_size);
1480 if (err < 0) {
1481 kfree(mem);
1482 return err;
1483 }
1484 if (prot->version == TLS_1_3_VERSION)
1485 memcpy(iv + iv_offset, tls_ctx->rx.iv,
1486 crypto_aead_ivsize(ctx->aead_recv));
1487 else
1488 memcpy(iv + iv_offset, tls_ctx->rx.iv, prot->salt_size);
1489
1490 xor_iv_with_seq(prot->version, iv + iv_offset, tls_ctx->rx.rec_seq);
1491
1492 /* Prepare AAD */
1493 tls_make_aad(aad, rxm->full_len - prot->overhead_size +
1494 prot->tail_size,
1495 tls_ctx->rx.rec_seq, prot->rec_seq_size,
1496 ctx->control, prot->version);
1497
1498 /* Prepare sgin */
1499 sg_init_table(sgin, n_sgin);
1500 sg_set_buf(&sgin[0], aad, prot->aad_size);
1501 err = skb_to_sgvec(skb, &sgin[1],
1502 rxm->offset + prot->prepend_size,
1503 rxm->full_len - prot->prepend_size);
1504 if (err < 0) {
1505 kfree(mem);
1506 return err;
1507 }
1508
1509 if (n_sgout) {
1510 if (out_iov) {
1511 sg_init_table(sgout, n_sgout);
1512 sg_set_buf(&sgout[0], aad, prot->aad_size);
1513
1514 *chunk = 0;
1515 err = tls_setup_from_iter(sk, out_iov, data_len,
1516 &pages, chunk, &sgout[1],
1517 (n_sgout - 1));
1518 if (err < 0)
1519 goto fallback_to_reg_recv;
1520 } else if (out_sg) {
1521 memcpy(sgout, out_sg, n_sgout * sizeof(*sgout));
1522 } else {
1523 goto fallback_to_reg_recv;
1524 }
1525 } else {
1526 fallback_to_reg_recv:
1527 sgout = sgin;
1528 pages = 0;
1529 *chunk = data_len;
1530 *zc = false;
1531 }
1532
1533 /* Prepare and submit AEAD request */
1534 err = tls_do_decryption(sk, skb, sgin, sgout, iv,
1535 data_len, aead_req, async);
1536 if (err == -EINPROGRESS)
1537 return err;
1538
1539 /* Release the pages in case iov was mapped to pages */
1540 for (; pages > 0; pages--)
1541 put_page(sg_page(&sgout[pages]));
1542
1543 kfree(mem);
1544 return err;
1545 }
1546
decrypt_skb_update(struct sock * sk,struct sk_buff * skb,struct iov_iter * dest,int * chunk,bool * zc,bool async)1547 static int decrypt_skb_update(struct sock *sk, struct sk_buff *skb,
1548 struct iov_iter *dest, int *chunk, bool *zc,
1549 bool async)
1550 {
1551 struct tls_context *tls_ctx = tls_get_ctx(sk);
1552 struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
1553 struct tls_prot_info *prot = &tls_ctx->prot_info;
1554 struct strp_msg *rxm = strp_msg(skb);
1555 int pad, err = 0;
1556
1557 if (!ctx->decrypted) {
1558 if (tls_ctx->rx_conf == TLS_HW) {
1559 err = tls_device_decrypted(sk, tls_ctx, skb, rxm);
1560 if (err < 0)
1561 return err;
1562 }
1563
1564 /* Still not decrypted after tls_device */
1565 if (!ctx->decrypted) {
1566 err = decrypt_internal(sk, skb, dest, NULL, chunk, zc,
1567 async);
1568 if (err < 0) {
1569 if (err == -EINPROGRESS)
1570 tls_advance_record_sn(sk, prot,
1571 &tls_ctx->rx);
1572 else if (err == -EBADMSG)
1573 TLS_INC_STATS(sock_net(sk),
1574 LINUX_MIB_TLSDECRYPTERROR);
1575 return err;
1576 }
1577 } else {
1578 *zc = false;
1579 }
1580
1581 pad = padding_length(ctx, prot, skb);
1582 if (pad < 0)
1583 return pad;
1584
1585 rxm->full_len -= pad;
1586 rxm->offset += prot->prepend_size;
1587 rxm->full_len -= prot->overhead_size;
1588 tls_advance_record_sn(sk, prot, &tls_ctx->rx);
1589 ctx->decrypted = 1;
1590 ctx->saved_data_ready(sk);
1591 } else {
1592 *zc = false;
1593 }
1594
1595 return err;
1596 }
1597
decrypt_skb(struct sock * sk,struct sk_buff * skb,struct scatterlist * sgout)1598 int decrypt_skb(struct sock *sk, struct sk_buff *skb,
1599 struct scatterlist *sgout)
1600 {
1601 bool zc = true;
1602 int chunk;
1603
1604 return decrypt_internal(sk, skb, NULL, sgout, &chunk, &zc, false);
1605 }
1606
tls_sw_advance_skb(struct sock * sk,struct sk_buff * skb,unsigned int len)1607 static bool tls_sw_advance_skb(struct sock *sk, struct sk_buff *skb,
1608 unsigned int len)
1609 {
1610 struct tls_context *tls_ctx = tls_get_ctx(sk);
1611 struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
1612
1613 if (skb) {
1614 struct strp_msg *rxm = strp_msg(skb);
1615
1616 if (len < rxm->full_len) {
1617 rxm->offset += len;
1618 rxm->full_len -= len;
1619 return false;
1620 }
1621 consume_skb(skb);
1622 }
1623
1624 /* Finished with message */
1625 ctx->recv_pkt = NULL;
1626 __strp_unpause(&ctx->strp);
1627
1628 return true;
1629 }
1630
1631 /* This function traverses the rx_list in tls receive context to copies the
1632 * decrypted records into the buffer provided by caller zero copy is not
1633 * true. Further, the records are removed from the rx_list if it is not a peek
1634 * case and the record has been consumed completely.
1635 */
process_rx_list(struct tls_sw_context_rx * ctx,struct msghdr * msg,u8 * control,bool * cmsg,size_t skip,size_t len,bool zc,bool is_peek)1636 static int process_rx_list(struct tls_sw_context_rx *ctx,
1637 struct msghdr *msg,
1638 u8 *control,
1639 bool *cmsg,
1640 size_t skip,
1641 size_t len,
1642 bool zc,
1643 bool is_peek)
1644 {
1645 struct sk_buff *skb = skb_peek(&ctx->rx_list);
1646 u8 ctrl = *control;
1647 u8 msgc = *cmsg;
1648 struct tls_msg *tlm;
1649 ssize_t copied = 0;
1650
1651 /* Set the record type in 'control' if caller didn't pass it */
1652 if (!ctrl && skb) {
1653 tlm = tls_msg(skb);
1654 ctrl = tlm->control;
1655 }
1656
1657 while (skip && skb) {
1658 struct strp_msg *rxm = strp_msg(skb);
1659 tlm = tls_msg(skb);
1660
1661 /* Cannot process a record of different type */
1662 if (ctrl != tlm->control)
1663 return 0;
1664
1665 if (skip < rxm->full_len)
1666 break;
1667
1668 skip = skip - rxm->full_len;
1669 skb = skb_peek_next(skb, &ctx->rx_list);
1670 }
1671
1672 while (len && skb) {
1673 struct sk_buff *next_skb;
1674 struct strp_msg *rxm = strp_msg(skb);
1675 int chunk = min_t(unsigned int, rxm->full_len - skip, len);
1676
1677 tlm = tls_msg(skb);
1678
1679 /* Cannot process a record of different type */
1680 if (ctrl != tlm->control)
1681 return 0;
1682
1683 /* Set record type if not already done. For a non-data record,
1684 * do not proceed if record type could not be copied.
1685 */
1686 if (!msgc) {
1687 int cerr = put_cmsg(msg, SOL_TLS, TLS_GET_RECORD_TYPE,
1688 sizeof(ctrl), &ctrl);
1689 msgc = true;
1690 if (ctrl != TLS_RECORD_TYPE_DATA) {
1691 if (cerr || msg->msg_flags & MSG_CTRUNC)
1692 return -EIO;
1693
1694 *cmsg = msgc;
1695 }
1696 }
1697
1698 if (!zc || (rxm->full_len - skip) > len) {
1699 int err = skb_copy_datagram_msg(skb, rxm->offset + skip,
1700 msg, chunk);
1701 if (err < 0)
1702 return err;
1703 }
1704
1705 len = len - chunk;
1706 copied = copied + chunk;
1707
1708 /* Consume the data from record if it is non-peek case*/
1709 if (!is_peek) {
1710 rxm->offset = rxm->offset + chunk;
1711 rxm->full_len = rxm->full_len - chunk;
1712
1713 /* Return if there is unconsumed data in the record */
1714 if (rxm->full_len - skip)
1715 break;
1716 }
1717
1718 /* The remaining skip-bytes must lie in 1st record in rx_list.
1719 * So from the 2nd record, 'skip' should be 0.
1720 */
1721 skip = 0;
1722
1723 if (msg)
1724 msg->msg_flags |= MSG_EOR;
1725
1726 next_skb = skb_peek_next(skb, &ctx->rx_list);
1727
1728 if (!is_peek) {
1729 skb_unlink(skb, &ctx->rx_list);
1730 consume_skb(skb);
1731 }
1732
1733 skb = next_skb;
1734 }
1735
1736 *control = ctrl;
1737 return copied;
1738 }
1739
tls_sw_recvmsg(struct sock * sk,struct msghdr * msg,size_t len,int nonblock,int flags,int * addr_len)1740 int tls_sw_recvmsg(struct sock *sk,
1741 struct msghdr *msg,
1742 size_t len,
1743 int nonblock,
1744 int flags,
1745 int *addr_len)
1746 {
1747 struct tls_context *tls_ctx = tls_get_ctx(sk);
1748 struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
1749 struct tls_prot_info *prot = &tls_ctx->prot_info;
1750 struct sk_psock *psock;
1751 unsigned char control = 0;
1752 ssize_t decrypted = 0;
1753 struct strp_msg *rxm;
1754 struct tls_msg *tlm;
1755 struct sk_buff *skb;
1756 ssize_t copied = 0;
1757 bool cmsg = false;
1758 int target, err = 0;
1759 long timeo;
1760 bool is_kvec = iov_iter_is_kvec(&msg->msg_iter);
1761 bool is_peek = flags & MSG_PEEK;
1762 bool bpf_strp_enabled;
1763 int num_async = 0;
1764 int pending;
1765
1766 flags |= nonblock;
1767
1768 if (unlikely(flags & MSG_ERRQUEUE))
1769 return sock_recv_errqueue(sk, msg, len, SOL_IP, IP_RECVERR);
1770
1771 psock = sk_psock_get(sk);
1772 lock_sock(sk);
1773 bpf_strp_enabled = sk_psock_strp_enabled(psock);
1774
1775 /* Process pending decrypted records. It must be non-zero-copy */
1776 err = process_rx_list(ctx, msg, &control, &cmsg, 0, len, false,
1777 is_peek);
1778 if (err < 0) {
1779 tls_err_abort(sk, err);
1780 goto end;
1781 } else {
1782 copied = err;
1783 }
1784
1785 if (len <= copied)
1786 goto recv_end;
1787
1788 target = sock_rcvlowat(sk, flags & MSG_WAITALL, len);
1789 len = len - copied;
1790 timeo = sock_rcvtimeo(sk, flags & MSG_DONTWAIT);
1791
1792 while (len && (decrypted + copied < target || ctx->recv_pkt)) {
1793 bool retain_skb = false;
1794 bool zc = false;
1795 int to_decrypt;
1796 int chunk = 0;
1797 bool async_capable;
1798 bool async = false;
1799
1800 skb = tls_wait_data(sk, psock, flags & MSG_DONTWAIT, timeo, &err);
1801 if (!skb) {
1802 if (psock) {
1803 int ret = __tcp_bpf_recvmsg(sk, psock,
1804 msg, len, flags);
1805
1806 if (ret > 0) {
1807 decrypted += ret;
1808 len -= ret;
1809 continue;
1810 }
1811 }
1812 goto recv_end;
1813 } else {
1814 tlm = tls_msg(skb);
1815 if (prot->version == TLS_1_3_VERSION)
1816 tlm->control = 0;
1817 else
1818 tlm->control = ctx->control;
1819 }
1820
1821 rxm = strp_msg(skb);
1822
1823 to_decrypt = rxm->full_len - prot->overhead_size;
1824
1825 if (to_decrypt <= len && !is_kvec && !is_peek &&
1826 ctx->control == TLS_RECORD_TYPE_DATA &&
1827 prot->version != TLS_1_3_VERSION &&
1828 !bpf_strp_enabled)
1829 zc = true;
1830
1831 /* Do not use async mode if record is non-data */
1832 if (ctx->control == TLS_RECORD_TYPE_DATA && !bpf_strp_enabled)
1833 async_capable = ctx->async_capable;
1834 else
1835 async_capable = false;
1836
1837 err = decrypt_skb_update(sk, skb, &msg->msg_iter,
1838 &chunk, &zc, async_capable);
1839 if (err < 0 && err != -EINPROGRESS) {
1840 tls_err_abort(sk, -EBADMSG);
1841 goto recv_end;
1842 }
1843
1844 if (err == -EINPROGRESS) {
1845 async = true;
1846 num_async++;
1847 } else if (prot->version == TLS_1_3_VERSION) {
1848 tlm->control = ctx->control;
1849 }
1850
1851 /* If the type of records being processed is not known yet,
1852 * set it to record type just dequeued. If it is already known,
1853 * but does not match the record type just dequeued, go to end.
1854 * We always get record type here since for tls1.2, record type
1855 * is known just after record is dequeued from stream parser.
1856 * For tls1.3, we disable async.
1857 */
1858
1859 if (!control)
1860 control = tlm->control;
1861 else if (control != tlm->control)
1862 goto recv_end;
1863
1864 if (!cmsg) {
1865 int cerr;
1866
1867 cerr = put_cmsg(msg, SOL_TLS, TLS_GET_RECORD_TYPE,
1868 sizeof(control), &control);
1869 cmsg = true;
1870 if (control != TLS_RECORD_TYPE_DATA) {
1871 if (cerr || msg->msg_flags & MSG_CTRUNC) {
1872 err = -EIO;
1873 goto recv_end;
1874 }
1875 }
1876 }
1877
1878 if (async)
1879 goto pick_next_record;
1880
1881 if (!zc) {
1882 if (bpf_strp_enabled) {
1883 err = sk_psock_tls_strp_read(psock, skb);
1884 if (err != __SK_PASS) {
1885 rxm->offset = rxm->offset + rxm->full_len;
1886 rxm->full_len = 0;
1887 if (err == __SK_DROP)
1888 consume_skb(skb);
1889 ctx->recv_pkt = NULL;
1890 __strp_unpause(&ctx->strp);
1891 continue;
1892 }
1893 }
1894
1895 if (rxm->full_len > len) {
1896 retain_skb = true;
1897 chunk = len;
1898 } else {
1899 chunk = rxm->full_len;
1900 }
1901
1902 err = skb_copy_datagram_msg(skb, rxm->offset,
1903 msg, chunk);
1904 if (err < 0)
1905 goto recv_end;
1906
1907 if (!is_peek) {
1908 rxm->offset = rxm->offset + chunk;
1909 rxm->full_len = rxm->full_len - chunk;
1910 }
1911 }
1912
1913 pick_next_record:
1914 if (chunk > len)
1915 chunk = len;
1916
1917 decrypted += chunk;
1918 len -= chunk;
1919
1920 /* For async or peek case, queue the current skb */
1921 if (async || is_peek || retain_skb) {
1922 skb_queue_tail(&ctx->rx_list, skb);
1923 skb = NULL;
1924 }
1925
1926 if (tls_sw_advance_skb(sk, skb, chunk)) {
1927 /* Return full control message to
1928 * userspace before trying to parse
1929 * another message type
1930 */
1931 msg->msg_flags |= MSG_EOR;
1932 if (control != TLS_RECORD_TYPE_DATA)
1933 goto recv_end;
1934 } else {
1935 break;
1936 }
1937 }
1938
1939 recv_end:
1940 if (num_async) {
1941 /* Wait for all previously submitted records to be decrypted */
1942 spin_lock_bh(&ctx->decrypt_compl_lock);
1943 ctx->async_notify = true;
1944 pending = atomic_read(&ctx->decrypt_pending);
1945 spin_unlock_bh(&ctx->decrypt_compl_lock);
1946 if (pending) {
1947 err = crypto_wait_req(-EINPROGRESS, &ctx->async_wait);
1948 if (err) {
1949 /* one of async decrypt failed */
1950 tls_err_abort(sk, err);
1951 copied = 0;
1952 decrypted = 0;
1953 goto end;
1954 }
1955 } else {
1956 reinit_completion(&ctx->async_wait.completion);
1957 }
1958
1959 /* There can be no concurrent accesses, since we have no
1960 * pending decrypt operations
1961 */
1962 WRITE_ONCE(ctx->async_notify, false);
1963
1964 /* Drain records from the rx_list & copy if required */
1965 if (is_peek || is_kvec)
1966 err = process_rx_list(ctx, msg, &control, &cmsg, copied,
1967 decrypted, false, is_peek);
1968 else
1969 err = process_rx_list(ctx, msg, &control, &cmsg, 0,
1970 decrypted, true, is_peek);
1971 if (err < 0) {
1972 tls_err_abort(sk, err);
1973 copied = 0;
1974 goto end;
1975 }
1976 }
1977
1978 copied += decrypted;
1979
1980 end:
1981 release_sock(sk);
1982 if (psock)
1983 sk_psock_put(sk, psock);
1984 return copied ? : err;
1985 }
1986
tls_sw_splice_read(struct socket * sock,loff_t * ppos,struct pipe_inode_info * pipe,size_t len,unsigned int flags)1987 ssize_t tls_sw_splice_read(struct socket *sock, loff_t *ppos,
1988 struct pipe_inode_info *pipe,
1989 size_t len, unsigned int flags)
1990 {
1991 struct tls_context *tls_ctx = tls_get_ctx(sock->sk);
1992 struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
1993 struct strp_msg *rxm = NULL;
1994 struct sock *sk = sock->sk;
1995 struct sk_buff *skb;
1996 ssize_t copied = 0;
1997 int err = 0;
1998 long timeo;
1999 int chunk;
2000 bool zc = false;
2001
2002 lock_sock(sk);
2003
2004 timeo = sock_rcvtimeo(sk, flags & SPLICE_F_NONBLOCK);
2005
2006 skb = tls_wait_data(sk, NULL, flags & SPLICE_F_NONBLOCK, timeo, &err);
2007 if (!skb)
2008 goto splice_read_end;
2009
2010 err = decrypt_skb_update(sk, skb, NULL, &chunk, &zc, false);
2011 if (err < 0) {
2012 tls_err_abort(sk, -EBADMSG);
2013 goto splice_read_end;
2014 }
2015
2016 /* splice does not support reading control messages */
2017 if (ctx->control != TLS_RECORD_TYPE_DATA) {
2018 err = -EINVAL;
2019 goto splice_read_end;
2020 }
2021
2022 rxm = strp_msg(skb);
2023
2024 chunk = min_t(unsigned int, rxm->full_len, len);
2025 copied = skb_splice_bits(skb, sk, rxm->offset, pipe, chunk, flags);
2026 if (copied < 0)
2027 goto splice_read_end;
2028
2029 if (likely(!(flags & MSG_PEEK)))
2030 tls_sw_advance_skb(sk, skb, copied);
2031
2032 splice_read_end:
2033 release_sock(sk);
2034 return copied ? : err;
2035 }
2036
tls_sw_stream_read(const struct sock * sk)2037 bool tls_sw_stream_read(const struct sock *sk)
2038 {
2039 struct tls_context *tls_ctx = tls_get_ctx(sk);
2040 struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
2041 bool ingress_empty = true;
2042 struct sk_psock *psock;
2043
2044 rcu_read_lock();
2045 psock = sk_psock(sk);
2046 if (psock)
2047 ingress_empty = list_empty(&psock->ingress_msg);
2048 rcu_read_unlock();
2049
2050 return !ingress_empty || ctx->recv_pkt ||
2051 !skb_queue_empty(&ctx->rx_list);
2052 }
2053
tls_read_size(struct strparser * strp,struct sk_buff * skb)2054 static int tls_read_size(struct strparser *strp, struct sk_buff *skb)
2055 {
2056 struct tls_context *tls_ctx = tls_get_ctx(strp->sk);
2057 struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
2058 struct tls_prot_info *prot = &tls_ctx->prot_info;
2059 char header[TLS_HEADER_SIZE + MAX_IV_SIZE];
2060 struct strp_msg *rxm = strp_msg(skb);
2061 size_t cipher_overhead;
2062 size_t data_len = 0;
2063 int ret;
2064
2065 /* Verify that we have a full TLS header, or wait for more data */
2066 if (rxm->offset + prot->prepend_size > skb->len)
2067 return 0;
2068
2069 /* Sanity-check size of on-stack buffer. */
2070 if (WARN_ON(prot->prepend_size > sizeof(header))) {
2071 ret = -EINVAL;
2072 goto read_failure;
2073 }
2074
2075 /* Linearize header to local buffer */
2076 ret = skb_copy_bits(skb, rxm->offset, header, prot->prepend_size);
2077
2078 if (ret < 0)
2079 goto read_failure;
2080
2081 ctx->control = header[0];
2082
2083 data_len = ((header[4] & 0xFF) | (header[3] << 8));
2084
2085 cipher_overhead = prot->tag_size;
2086 if (prot->version != TLS_1_3_VERSION)
2087 cipher_overhead += prot->iv_size;
2088
2089 if (data_len > TLS_MAX_PAYLOAD_SIZE + cipher_overhead +
2090 prot->tail_size) {
2091 ret = -EMSGSIZE;
2092 goto read_failure;
2093 }
2094 if (data_len < cipher_overhead) {
2095 ret = -EBADMSG;
2096 goto read_failure;
2097 }
2098
2099 /* Note that both TLS1.3 and TLS1.2 use TLS_1_2 version here */
2100 if (header[1] != TLS_1_2_VERSION_MINOR ||
2101 header[2] != TLS_1_2_VERSION_MAJOR) {
2102 ret = -EINVAL;
2103 goto read_failure;
2104 }
2105
2106 tls_device_rx_resync_new_rec(strp->sk, data_len + TLS_HEADER_SIZE,
2107 TCP_SKB_CB(skb)->seq + rxm->offset);
2108 return data_len + TLS_HEADER_SIZE;
2109
2110 read_failure:
2111 tls_err_abort(strp->sk, ret);
2112
2113 return ret;
2114 }
2115
tls_queue(struct strparser * strp,struct sk_buff * skb)2116 static void tls_queue(struct strparser *strp, struct sk_buff *skb)
2117 {
2118 struct tls_context *tls_ctx = tls_get_ctx(strp->sk);
2119 struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
2120
2121 ctx->decrypted = 0;
2122
2123 ctx->recv_pkt = skb;
2124 strp_pause(strp);
2125
2126 ctx->saved_data_ready(strp->sk);
2127 }
2128
tls_data_ready(struct sock * sk)2129 static void tls_data_ready(struct sock *sk)
2130 {
2131 struct tls_context *tls_ctx = tls_get_ctx(sk);
2132 struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
2133 struct sk_psock *psock;
2134
2135 strp_data_ready(&ctx->strp);
2136
2137 psock = sk_psock_get(sk);
2138 if (psock) {
2139 if (!list_empty(&psock->ingress_msg))
2140 ctx->saved_data_ready(sk);
2141 sk_psock_put(sk, psock);
2142 }
2143 }
2144
tls_sw_cancel_work_tx(struct tls_context * tls_ctx)2145 void tls_sw_cancel_work_tx(struct tls_context *tls_ctx)
2146 {
2147 struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
2148
2149 set_bit(BIT_TX_CLOSING, &ctx->tx_bitmask);
2150 set_bit(BIT_TX_SCHEDULED, &ctx->tx_bitmask);
2151 cancel_delayed_work_sync(&ctx->tx_work.work);
2152 }
2153
tls_sw_release_resources_tx(struct sock * sk)2154 void tls_sw_release_resources_tx(struct sock *sk)
2155 {
2156 struct tls_context *tls_ctx = tls_get_ctx(sk);
2157 struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
2158 struct tls_rec *rec, *tmp;
2159 int pending;
2160
2161 /* Wait for any pending async encryptions to complete */
2162 spin_lock_bh(&ctx->encrypt_compl_lock);
2163 ctx->async_notify = true;
2164 pending = atomic_read(&ctx->encrypt_pending);
2165 spin_unlock_bh(&ctx->encrypt_compl_lock);
2166
2167 if (pending)
2168 crypto_wait_req(-EINPROGRESS, &ctx->async_wait);
2169
2170 tls_tx_records(sk, -1);
2171
2172 /* Free up un-sent records in tx_list. First, free
2173 * the partially sent record if any at head of tx_list.
2174 */
2175 if (tls_ctx->partially_sent_record) {
2176 tls_free_partial_record(sk, tls_ctx);
2177 rec = list_first_entry(&ctx->tx_list,
2178 struct tls_rec, list);
2179 list_del(&rec->list);
2180 sk_msg_free(sk, &rec->msg_plaintext);
2181 kfree(rec);
2182 }
2183
2184 list_for_each_entry_safe(rec, tmp, &ctx->tx_list, list) {
2185 list_del(&rec->list);
2186 sk_msg_free(sk, &rec->msg_encrypted);
2187 sk_msg_free(sk, &rec->msg_plaintext);
2188 kfree(rec);
2189 }
2190
2191 crypto_free_aead(ctx->aead_send);
2192 tls_free_open_rec(sk);
2193 }
2194
tls_sw_free_ctx_tx(struct tls_context * tls_ctx)2195 void tls_sw_free_ctx_tx(struct tls_context *tls_ctx)
2196 {
2197 struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
2198
2199 kfree(ctx);
2200 }
2201
tls_sw_release_resources_rx(struct sock * sk)2202 void tls_sw_release_resources_rx(struct sock *sk)
2203 {
2204 struct tls_context *tls_ctx = tls_get_ctx(sk);
2205 struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
2206
2207 kfree(tls_ctx->rx.rec_seq);
2208 kfree(tls_ctx->rx.iv);
2209
2210 if (ctx->aead_recv) {
2211 kfree_skb(ctx->recv_pkt);
2212 ctx->recv_pkt = NULL;
2213 skb_queue_purge(&ctx->rx_list);
2214 crypto_free_aead(ctx->aead_recv);
2215 strp_stop(&ctx->strp);
2216 /* If tls_sw_strparser_arm() was not called (cleanup paths)
2217 * we still want to strp_stop(), but sk->sk_data_ready was
2218 * never swapped.
2219 */
2220 if (ctx->saved_data_ready) {
2221 write_lock_bh(&sk->sk_callback_lock);
2222 sk->sk_data_ready = ctx->saved_data_ready;
2223 write_unlock_bh(&sk->sk_callback_lock);
2224 }
2225 }
2226 }
2227
tls_sw_strparser_done(struct tls_context * tls_ctx)2228 void tls_sw_strparser_done(struct tls_context *tls_ctx)
2229 {
2230 struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
2231
2232 strp_done(&ctx->strp);
2233 }
2234
tls_sw_free_ctx_rx(struct tls_context * tls_ctx)2235 void tls_sw_free_ctx_rx(struct tls_context *tls_ctx)
2236 {
2237 struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
2238
2239 kfree(ctx);
2240 }
2241
tls_sw_free_resources_rx(struct sock * sk)2242 void tls_sw_free_resources_rx(struct sock *sk)
2243 {
2244 struct tls_context *tls_ctx = tls_get_ctx(sk);
2245
2246 tls_sw_release_resources_rx(sk);
2247 tls_sw_free_ctx_rx(tls_ctx);
2248 }
2249
2250 /* The work handler to transmitt the encrypted records in tx_list */
tx_work_handler(struct work_struct * work)2251 static void tx_work_handler(struct work_struct *work)
2252 {
2253 struct delayed_work *delayed_work = to_delayed_work(work);
2254 struct tx_work *tx_work = container_of(delayed_work,
2255 struct tx_work, work);
2256 struct sock *sk = tx_work->sk;
2257 struct tls_context *tls_ctx = tls_get_ctx(sk);
2258 struct tls_sw_context_tx *ctx;
2259
2260 if (unlikely(!tls_ctx))
2261 return;
2262
2263 ctx = tls_sw_ctx_tx(tls_ctx);
2264 if (test_bit(BIT_TX_CLOSING, &ctx->tx_bitmask))
2265 return;
2266
2267 if (!test_and_clear_bit(BIT_TX_SCHEDULED, &ctx->tx_bitmask))
2268 return;
2269 mutex_lock(&tls_ctx->tx_lock);
2270 lock_sock(sk);
2271 tls_tx_records(sk, -1);
2272 release_sock(sk);
2273 mutex_unlock(&tls_ctx->tx_lock);
2274 }
2275
tls_sw_write_space(struct sock * sk,struct tls_context * ctx)2276 void tls_sw_write_space(struct sock *sk, struct tls_context *ctx)
2277 {
2278 struct tls_sw_context_tx *tx_ctx = tls_sw_ctx_tx(ctx);
2279
2280 /* Schedule the transmission if tx list is ready */
2281 if (is_tx_ready(tx_ctx) &&
2282 !test_and_set_bit(BIT_TX_SCHEDULED, &tx_ctx->tx_bitmask))
2283 schedule_delayed_work(&tx_ctx->tx_work.work, 0);
2284 }
2285
tls_sw_strparser_arm(struct sock * sk,struct tls_context * tls_ctx)2286 void tls_sw_strparser_arm(struct sock *sk, struct tls_context *tls_ctx)
2287 {
2288 struct tls_sw_context_rx *rx_ctx = tls_sw_ctx_rx(tls_ctx);
2289
2290 write_lock_bh(&sk->sk_callback_lock);
2291 rx_ctx->saved_data_ready = sk->sk_data_ready;
2292 sk->sk_data_ready = tls_data_ready;
2293 write_unlock_bh(&sk->sk_callback_lock);
2294
2295 strp_check_rcv(&rx_ctx->strp);
2296 }
2297
tls_set_sw_offload(struct sock * sk,struct tls_context * ctx,int tx)2298 int tls_set_sw_offload(struct sock *sk, struct tls_context *ctx, int tx)
2299 {
2300 struct tls_context *tls_ctx = tls_get_ctx(sk);
2301 struct tls_prot_info *prot = &tls_ctx->prot_info;
2302 struct tls_crypto_info *crypto_info;
2303 struct tls12_crypto_info_aes_gcm_128 *gcm_128_info;
2304 struct tls12_crypto_info_aes_gcm_256 *gcm_256_info;
2305 struct tls12_crypto_info_aes_ccm_128 *ccm_128_info;
2306 struct tls_sw_context_tx *sw_ctx_tx = NULL;
2307 struct tls_sw_context_rx *sw_ctx_rx = NULL;
2308 struct cipher_context *cctx;
2309 struct crypto_aead **aead;
2310 struct strp_callbacks cb;
2311 u16 nonce_size, tag_size, iv_size, rec_seq_size, salt_size;
2312 struct crypto_tfm *tfm;
2313 char *iv, *rec_seq, *key, *salt, *cipher_name;
2314 size_t keysize;
2315 int rc = 0;
2316
2317 if (!ctx) {
2318 rc = -EINVAL;
2319 goto out;
2320 }
2321
2322 if (tx) {
2323 if (!ctx->priv_ctx_tx) {
2324 sw_ctx_tx = kzalloc(sizeof(*sw_ctx_tx), GFP_KERNEL);
2325 if (!sw_ctx_tx) {
2326 rc = -ENOMEM;
2327 goto out;
2328 }
2329 ctx->priv_ctx_tx = sw_ctx_tx;
2330 } else {
2331 sw_ctx_tx =
2332 (struct tls_sw_context_tx *)ctx->priv_ctx_tx;
2333 }
2334 } else {
2335 if (!ctx->priv_ctx_rx) {
2336 sw_ctx_rx = kzalloc(sizeof(*sw_ctx_rx), GFP_KERNEL);
2337 if (!sw_ctx_rx) {
2338 rc = -ENOMEM;
2339 goto out;
2340 }
2341 ctx->priv_ctx_rx = sw_ctx_rx;
2342 } else {
2343 sw_ctx_rx =
2344 (struct tls_sw_context_rx *)ctx->priv_ctx_rx;
2345 }
2346 }
2347
2348 if (tx) {
2349 crypto_init_wait(&sw_ctx_tx->async_wait);
2350 spin_lock_init(&sw_ctx_tx->encrypt_compl_lock);
2351 crypto_info = &ctx->crypto_send.info;
2352 cctx = &ctx->tx;
2353 aead = &sw_ctx_tx->aead_send;
2354 INIT_LIST_HEAD(&sw_ctx_tx->tx_list);
2355 INIT_DELAYED_WORK(&sw_ctx_tx->tx_work.work, tx_work_handler);
2356 sw_ctx_tx->tx_work.sk = sk;
2357 } else {
2358 crypto_init_wait(&sw_ctx_rx->async_wait);
2359 spin_lock_init(&sw_ctx_rx->decrypt_compl_lock);
2360 crypto_info = &ctx->crypto_recv.info;
2361 cctx = &ctx->rx;
2362 skb_queue_head_init(&sw_ctx_rx->rx_list);
2363 aead = &sw_ctx_rx->aead_recv;
2364 }
2365
2366 switch (crypto_info->cipher_type) {
2367 case TLS_CIPHER_AES_GCM_128: {
2368 nonce_size = TLS_CIPHER_AES_GCM_128_IV_SIZE;
2369 tag_size = TLS_CIPHER_AES_GCM_128_TAG_SIZE;
2370 iv_size = TLS_CIPHER_AES_GCM_128_IV_SIZE;
2371 iv = ((struct tls12_crypto_info_aes_gcm_128 *)crypto_info)->iv;
2372 rec_seq_size = TLS_CIPHER_AES_GCM_128_REC_SEQ_SIZE;
2373 rec_seq =
2374 ((struct tls12_crypto_info_aes_gcm_128 *)crypto_info)->rec_seq;
2375 gcm_128_info =
2376 (struct tls12_crypto_info_aes_gcm_128 *)crypto_info;
2377 keysize = TLS_CIPHER_AES_GCM_128_KEY_SIZE;
2378 key = gcm_128_info->key;
2379 salt = gcm_128_info->salt;
2380 salt_size = TLS_CIPHER_AES_GCM_128_SALT_SIZE;
2381 cipher_name = "gcm(aes)";
2382 break;
2383 }
2384 case TLS_CIPHER_AES_GCM_256: {
2385 nonce_size = TLS_CIPHER_AES_GCM_256_IV_SIZE;
2386 tag_size = TLS_CIPHER_AES_GCM_256_TAG_SIZE;
2387 iv_size = TLS_CIPHER_AES_GCM_256_IV_SIZE;
2388 iv = ((struct tls12_crypto_info_aes_gcm_256 *)crypto_info)->iv;
2389 rec_seq_size = TLS_CIPHER_AES_GCM_256_REC_SEQ_SIZE;
2390 rec_seq =
2391 ((struct tls12_crypto_info_aes_gcm_256 *)crypto_info)->rec_seq;
2392 gcm_256_info =
2393 (struct tls12_crypto_info_aes_gcm_256 *)crypto_info;
2394 keysize = TLS_CIPHER_AES_GCM_256_KEY_SIZE;
2395 key = gcm_256_info->key;
2396 salt = gcm_256_info->salt;
2397 salt_size = TLS_CIPHER_AES_GCM_256_SALT_SIZE;
2398 cipher_name = "gcm(aes)";
2399 break;
2400 }
2401 case TLS_CIPHER_AES_CCM_128: {
2402 nonce_size = TLS_CIPHER_AES_CCM_128_IV_SIZE;
2403 tag_size = TLS_CIPHER_AES_CCM_128_TAG_SIZE;
2404 iv_size = TLS_CIPHER_AES_CCM_128_IV_SIZE;
2405 iv = ((struct tls12_crypto_info_aes_ccm_128 *)crypto_info)->iv;
2406 rec_seq_size = TLS_CIPHER_AES_CCM_128_REC_SEQ_SIZE;
2407 rec_seq =
2408 ((struct tls12_crypto_info_aes_ccm_128 *)crypto_info)->rec_seq;
2409 ccm_128_info =
2410 (struct tls12_crypto_info_aes_ccm_128 *)crypto_info;
2411 keysize = TLS_CIPHER_AES_CCM_128_KEY_SIZE;
2412 key = ccm_128_info->key;
2413 salt = ccm_128_info->salt;
2414 salt_size = TLS_CIPHER_AES_CCM_128_SALT_SIZE;
2415 cipher_name = "ccm(aes)";
2416 break;
2417 }
2418 default:
2419 rc = -EINVAL;
2420 goto free_priv;
2421 }
2422
2423 /* Sanity-check the sizes for stack allocations. */
2424 if (iv_size > MAX_IV_SIZE || nonce_size > MAX_IV_SIZE ||
2425 rec_seq_size > TLS_MAX_REC_SEQ_SIZE) {
2426 rc = -EINVAL;
2427 goto free_priv;
2428 }
2429
2430 if (crypto_info->version == TLS_1_3_VERSION) {
2431 nonce_size = 0;
2432 prot->aad_size = TLS_HEADER_SIZE;
2433 prot->tail_size = 1;
2434 } else {
2435 prot->aad_size = TLS_AAD_SPACE_SIZE;
2436 prot->tail_size = 0;
2437 }
2438
2439 prot->version = crypto_info->version;
2440 prot->cipher_type = crypto_info->cipher_type;
2441 prot->prepend_size = TLS_HEADER_SIZE + nonce_size;
2442 prot->tag_size = tag_size;
2443 prot->overhead_size = prot->prepend_size +
2444 prot->tag_size + prot->tail_size;
2445 prot->iv_size = iv_size;
2446 prot->salt_size = salt_size;
2447 cctx->iv = kmalloc(iv_size + salt_size, GFP_KERNEL);
2448 if (!cctx->iv) {
2449 rc = -ENOMEM;
2450 goto free_priv;
2451 }
2452 /* Note: 128 & 256 bit salt are the same size */
2453 prot->rec_seq_size = rec_seq_size;
2454 memcpy(cctx->iv, salt, salt_size);
2455 memcpy(cctx->iv + salt_size, iv, iv_size);
2456 cctx->rec_seq = kmemdup(rec_seq, rec_seq_size, GFP_KERNEL);
2457 if (!cctx->rec_seq) {
2458 rc = -ENOMEM;
2459 goto free_iv;
2460 }
2461
2462 if (!*aead) {
2463 *aead = crypto_alloc_aead(cipher_name, 0, 0);
2464 if (IS_ERR(*aead)) {
2465 rc = PTR_ERR(*aead);
2466 *aead = NULL;
2467 goto free_rec_seq;
2468 }
2469 }
2470
2471 ctx->push_pending_record = tls_sw_push_pending_record;
2472
2473 rc = crypto_aead_setkey(*aead, key, keysize);
2474
2475 if (rc)
2476 goto free_aead;
2477
2478 rc = crypto_aead_setauthsize(*aead, prot->tag_size);
2479 if (rc)
2480 goto free_aead;
2481
2482 if (sw_ctx_rx) {
2483 tfm = crypto_aead_tfm(sw_ctx_rx->aead_recv);
2484
2485 if (crypto_info->version == TLS_1_3_VERSION)
2486 sw_ctx_rx->async_capable = 0;
2487 else
2488 sw_ctx_rx->async_capable =
2489 !!(tfm->__crt_alg->cra_flags &
2490 CRYPTO_ALG_ASYNC);
2491
2492 /* Set up strparser */
2493 memset(&cb, 0, sizeof(cb));
2494 cb.rcv_msg = tls_queue;
2495 cb.parse_msg = tls_read_size;
2496
2497 strp_init(&sw_ctx_rx->strp, sk, &cb);
2498 }
2499
2500 goto out;
2501
2502 free_aead:
2503 crypto_free_aead(*aead);
2504 *aead = NULL;
2505 free_rec_seq:
2506 kfree(cctx->rec_seq);
2507 cctx->rec_seq = NULL;
2508 free_iv:
2509 kfree(cctx->iv);
2510 cctx->iv = NULL;
2511 free_priv:
2512 if (tx) {
2513 kfree(ctx->priv_ctx_tx);
2514 ctx->priv_ctx_tx = NULL;
2515 } else {
2516 kfree(ctx->priv_ctx_rx);
2517 ctx->priv_ctx_rx = NULL;
2518 }
2519 out:
2520 return rc;
2521 }
2522