1 /* Copyright (c) 2018, Mellanox Technologies All rights reserved.
2 *
3 * This software is available to you under a choice of one of two
4 * licenses. You may choose to be licensed under the terms of the GNU
5 * General Public License (GPL) Version 2, available from the file
6 * COPYING in the main directory of this source tree, or the
7 * OpenIB.org BSD license below:
8 *
9 * Redistribution and use in source and binary forms, with or
10 * without modification, are permitted provided that the following
11 * conditions are met:
12 *
13 * - Redistributions of source code must retain the above
14 * copyright notice, this list of conditions and the following
15 * disclaimer.
16 *
17 * - Redistributions in binary form must reproduce the above
18 * copyright notice, this list of conditions and the following
19 * disclaimer in the documentation and/or other materials
20 * provided with the distribution.
21 *
22 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
23 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
24 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
25 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
26 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
27 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
28 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
29 * SOFTWARE.
30 */
31
32 #include <crypto/aead.h>
33 #include <linux/highmem.h>
34 #include <linux/module.h>
35 #include <linux/netdevice.h>
36 #include <net/dst.h>
37 #include <net/inet_connection_sock.h>
38 #include <net/tcp.h>
39 #include <net/tls.h>
40
41 /* device_offload_lock is used to synchronize tls_dev_add
42 * against NETDEV_DOWN notifications.
43 */
44 static DECLARE_RWSEM(device_offload_lock);
45
46 static void tls_device_gc_task(struct work_struct *work);
47
48 static DECLARE_WORK(tls_device_gc_work, tls_device_gc_task);
49 static LIST_HEAD(tls_device_gc_list);
50 static LIST_HEAD(tls_device_list);
51 static DEFINE_SPINLOCK(tls_device_lock);
52
tls_device_free_ctx(struct tls_context * ctx)53 static void tls_device_free_ctx(struct tls_context *ctx)
54 {
55 if (ctx->tx_conf == TLS_HW) {
56 kfree(tls_offload_ctx_tx(ctx));
57 kfree(ctx->tx.rec_seq);
58 kfree(ctx->tx.iv);
59 }
60
61 if (ctx->rx_conf == TLS_HW)
62 kfree(tls_offload_ctx_rx(ctx));
63
64 tls_ctx_free(NULL, ctx);
65 }
66
tls_device_gc_task(struct work_struct * work)67 static void tls_device_gc_task(struct work_struct *work)
68 {
69 struct tls_context *ctx, *tmp;
70 unsigned long flags;
71 LIST_HEAD(gc_list);
72
73 spin_lock_irqsave(&tls_device_lock, flags);
74 list_splice_init(&tls_device_gc_list, &gc_list);
75 spin_unlock_irqrestore(&tls_device_lock, flags);
76
77 list_for_each_entry_safe(ctx, tmp, &gc_list, list) {
78 struct net_device *netdev = ctx->netdev;
79
80 if (netdev && ctx->tx_conf == TLS_HW) {
81 netdev->tlsdev_ops->tls_dev_del(netdev, ctx,
82 TLS_OFFLOAD_CTX_DIR_TX);
83 dev_put(netdev);
84 ctx->netdev = NULL;
85 }
86
87 list_del(&ctx->list);
88 tls_device_free_ctx(ctx);
89 }
90 }
91
tls_device_queue_ctx_destruction(struct tls_context * ctx)92 static void tls_device_queue_ctx_destruction(struct tls_context *ctx)
93 {
94 unsigned long flags;
95
96 spin_lock_irqsave(&tls_device_lock, flags);
97 list_move_tail(&ctx->list, &tls_device_gc_list);
98
99 /* schedule_work inside the spinlock
100 * to make sure tls_device_down waits for that work.
101 */
102 schedule_work(&tls_device_gc_work);
103
104 spin_unlock_irqrestore(&tls_device_lock, flags);
105 }
106
107 /* We assume that the socket is already connected */
get_netdev_for_sock(struct sock * sk)108 static struct net_device *get_netdev_for_sock(struct sock *sk)
109 {
110 struct dst_entry *dst = sk_dst_get(sk);
111 struct net_device *netdev = NULL;
112
113 if (likely(dst)) {
114 netdev = dst->dev;
115 dev_hold(netdev);
116 }
117
118 dst_release(dst);
119
120 return netdev;
121 }
122
destroy_record(struct tls_record_info * record)123 static void destroy_record(struct tls_record_info *record)
124 {
125 int i;
126
127 for (i = 0; i < record->num_frags; i++)
128 __skb_frag_unref(&record->frags[i]);
129 kfree(record);
130 }
131
delete_all_records(struct tls_offload_context_tx * offload_ctx)132 static void delete_all_records(struct tls_offload_context_tx *offload_ctx)
133 {
134 struct tls_record_info *info, *temp;
135
136 list_for_each_entry_safe(info, temp, &offload_ctx->records_list, list) {
137 list_del(&info->list);
138 destroy_record(info);
139 }
140
141 offload_ctx->retransmit_hint = NULL;
142 }
143
tls_icsk_clean_acked(struct sock * sk,u32 acked_seq)144 static void tls_icsk_clean_acked(struct sock *sk, u32 acked_seq)
145 {
146 struct tls_context *tls_ctx = tls_get_ctx(sk);
147 struct tls_record_info *info, *temp;
148 struct tls_offload_context_tx *ctx;
149 u64 deleted_records = 0;
150 unsigned long flags;
151
152 if (!tls_ctx)
153 return;
154
155 ctx = tls_offload_ctx_tx(tls_ctx);
156
157 spin_lock_irqsave(&ctx->lock, flags);
158 info = ctx->retransmit_hint;
159 if (info && !before(acked_seq, info->end_seq))
160 ctx->retransmit_hint = NULL;
161
162 list_for_each_entry_safe(info, temp, &ctx->records_list, list) {
163 if (before(acked_seq, info->end_seq))
164 break;
165 list_del(&info->list);
166
167 destroy_record(info);
168 deleted_records++;
169 }
170
171 ctx->unacked_record_sn += deleted_records;
172 spin_unlock_irqrestore(&ctx->lock, flags);
173 }
174
175 /* At this point, there should be no references on this
176 * socket and no in-flight SKBs associated with this
177 * socket, so it is safe to free all the resources.
178 */
tls_device_sk_destruct(struct sock * sk)179 static void tls_device_sk_destruct(struct sock *sk)
180 {
181 struct tls_context *tls_ctx = tls_get_ctx(sk);
182 struct tls_offload_context_tx *ctx = tls_offload_ctx_tx(tls_ctx);
183
184 tls_ctx->sk_destruct(sk);
185
186 if (tls_ctx->tx_conf == TLS_HW) {
187 if (ctx->open_record)
188 destroy_record(ctx->open_record);
189 delete_all_records(ctx);
190 crypto_free_aead(ctx->aead_send);
191 clean_acked_data_disable(inet_csk(sk));
192 }
193
194 if (refcount_dec_and_test(&tls_ctx->refcount))
195 tls_device_queue_ctx_destruction(tls_ctx);
196 }
197
tls_device_free_resources_tx(struct sock * sk)198 void tls_device_free_resources_tx(struct sock *sk)
199 {
200 struct tls_context *tls_ctx = tls_get_ctx(sk);
201
202 tls_free_partial_record(sk, tls_ctx);
203 }
204
tls_device_resync_tx(struct sock * sk,struct tls_context * tls_ctx,u32 seq)205 static void tls_device_resync_tx(struct sock *sk, struct tls_context *tls_ctx,
206 u32 seq)
207 {
208 struct net_device *netdev;
209 struct sk_buff *skb;
210 int err = 0;
211 u8 *rcd_sn;
212
213 skb = tcp_write_queue_tail(sk);
214 if (skb)
215 TCP_SKB_CB(skb)->eor = 1;
216
217 rcd_sn = tls_ctx->tx.rec_seq;
218
219 down_read(&device_offload_lock);
220 netdev = tls_ctx->netdev;
221 if (netdev)
222 err = netdev->tlsdev_ops->tls_dev_resync(netdev, sk, seq,
223 rcd_sn,
224 TLS_OFFLOAD_CTX_DIR_TX);
225 up_read(&device_offload_lock);
226 if (err)
227 return;
228
229 clear_bit_unlock(TLS_TX_SYNC_SCHED, &tls_ctx->flags);
230 }
231
tls_append_frag(struct tls_record_info * record,struct page_frag * pfrag,int size)232 static void tls_append_frag(struct tls_record_info *record,
233 struct page_frag *pfrag,
234 int size)
235 {
236 skb_frag_t *frag;
237
238 frag = &record->frags[record->num_frags - 1];
239 if (skb_frag_page(frag) == pfrag->page &&
240 skb_frag_off(frag) + skb_frag_size(frag) == pfrag->offset) {
241 skb_frag_size_add(frag, size);
242 } else {
243 ++frag;
244 __skb_frag_set_page(frag, pfrag->page);
245 skb_frag_off_set(frag, pfrag->offset);
246 skb_frag_size_set(frag, size);
247 ++record->num_frags;
248 get_page(pfrag->page);
249 }
250
251 pfrag->offset += size;
252 record->len += size;
253 }
254
tls_push_record(struct sock * sk,struct tls_context * ctx,struct tls_offload_context_tx * offload_ctx,struct tls_record_info * record,int flags)255 static int tls_push_record(struct sock *sk,
256 struct tls_context *ctx,
257 struct tls_offload_context_tx *offload_ctx,
258 struct tls_record_info *record,
259 int flags)
260 {
261 struct tls_prot_info *prot = &ctx->prot_info;
262 struct tcp_sock *tp = tcp_sk(sk);
263 skb_frag_t *frag;
264 int i;
265
266 record->end_seq = tp->write_seq + record->len;
267 list_add_tail_rcu(&record->list, &offload_ctx->records_list);
268 offload_ctx->open_record = NULL;
269
270 if (test_bit(TLS_TX_SYNC_SCHED, &ctx->flags))
271 tls_device_resync_tx(sk, ctx, tp->write_seq);
272
273 tls_advance_record_sn(sk, prot, &ctx->tx);
274
275 for (i = 0; i < record->num_frags; i++) {
276 frag = &record->frags[i];
277 sg_unmark_end(&offload_ctx->sg_tx_data[i]);
278 sg_set_page(&offload_ctx->sg_tx_data[i], skb_frag_page(frag),
279 skb_frag_size(frag), skb_frag_off(frag));
280 sk_mem_charge(sk, skb_frag_size(frag));
281 get_page(skb_frag_page(frag));
282 }
283 sg_mark_end(&offload_ctx->sg_tx_data[record->num_frags - 1]);
284
285 /* all ready, send */
286 return tls_push_sg(sk, ctx, offload_ctx->sg_tx_data, 0, flags);
287 }
288
tls_device_record_close(struct sock * sk,struct tls_context * ctx,struct tls_record_info * record,struct page_frag * pfrag,unsigned char record_type)289 static int tls_device_record_close(struct sock *sk,
290 struct tls_context *ctx,
291 struct tls_record_info *record,
292 struct page_frag *pfrag,
293 unsigned char record_type)
294 {
295 struct tls_prot_info *prot = &ctx->prot_info;
296 int ret;
297
298 /* append tag
299 * device will fill in the tag, we just need to append a placeholder
300 * use socket memory to improve coalescing (re-using a single buffer
301 * increases frag count)
302 * if we can't allocate memory now, steal some back from data
303 */
304 if (likely(skb_page_frag_refill(prot->tag_size, pfrag,
305 sk->sk_allocation))) {
306 ret = 0;
307 tls_append_frag(record, pfrag, prot->tag_size);
308 } else {
309 ret = prot->tag_size;
310 if (record->len <= prot->overhead_size)
311 return -ENOMEM;
312 }
313
314 /* fill prepend */
315 tls_fill_prepend(ctx, skb_frag_address(&record->frags[0]),
316 record->len - prot->overhead_size,
317 record_type, prot->version);
318 return ret;
319 }
320
tls_create_new_record(struct tls_offload_context_tx * offload_ctx,struct page_frag * pfrag,size_t prepend_size)321 static int tls_create_new_record(struct tls_offload_context_tx *offload_ctx,
322 struct page_frag *pfrag,
323 size_t prepend_size)
324 {
325 struct tls_record_info *record;
326 skb_frag_t *frag;
327
328 record = kmalloc(sizeof(*record), GFP_KERNEL);
329 if (!record)
330 return -ENOMEM;
331
332 frag = &record->frags[0];
333 __skb_frag_set_page(frag, pfrag->page);
334 skb_frag_off_set(frag, pfrag->offset);
335 skb_frag_size_set(frag, prepend_size);
336
337 get_page(pfrag->page);
338 pfrag->offset += prepend_size;
339
340 record->num_frags = 1;
341 record->len = prepend_size;
342 offload_ctx->open_record = record;
343 return 0;
344 }
345
tls_do_allocation(struct sock * sk,struct tls_offload_context_tx * offload_ctx,struct page_frag * pfrag,size_t prepend_size)346 static int tls_do_allocation(struct sock *sk,
347 struct tls_offload_context_tx *offload_ctx,
348 struct page_frag *pfrag,
349 size_t prepend_size)
350 {
351 int ret;
352
353 if (!offload_ctx->open_record) {
354 if (unlikely(!skb_page_frag_refill(prepend_size, pfrag,
355 sk->sk_allocation))) {
356 sk->sk_prot->enter_memory_pressure(sk);
357 sk_stream_moderate_sndbuf(sk);
358 return -ENOMEM;
359 }
360
361 ret = tls_create_new_record(offload_ctx, pfrag, prepend_size);
362 if (ret)
363 return ret;
364
365 if (pfrag->size > pfrag->offset)
366 return 0;
367 }
368
369 if (!sk_page_frag_refill(sk, pfrag))
370 return -ENOMEM;
371
372 return 0;
373 }
374
tls_device_copy_data(void * addr,size_t bytes,struct iov_iter * i)375 static int tls_device_copy_data(void *addr, size_t bytes, struct iov_iter *i)
376 {
377 size_t pre_copy, nocache;
378
379 pre_copy = ~((unsigned long)addr - 1) & (SMP_CACHE_BYTES - 1);
380 if (pre_copy) {
381 pre_copy = min(pre_copy, bytes);
382 if (copy_from_iter(addr, pre_copy, i) != pre_copy)
383 return -EFAULT;
384 bytes -= pre_copy;
385 addr += pre_copy;
386 }
387
388 nocache = round_down(bytes, SMP_CACHE_BYTES);
389 if (copy_from_iter_nocache(addr, nocache, i) != nocache)
390 return -EFAULT;
391 bytes -= nocache;
392 addr += nocache;
393
394 if (bytes && copy_from_iter(addr, bytes, i) != bytes)
395 return -EFAULT;
396
397 return 0;
398 }
399
tls_push_data(struct sock * sk,struct iov_iter * msg_iter,size_t size,int flags,unsigned char record_type)400 static int tls_push_data(struct sock *sk,
401 struct iov_iter *msg_iter,
402 size_t size, int flags,
403 unsigned char record_type)
404 {
405 struct tls_context *tls_ctx = tls_get_ctx(sk);
406 struct tls_prot_info *prot = &tls_ctx->prot_info;
407 struct tls_offload_context_tx *ctx = tls_offload_ctx_tx(tls_ctx);
408 int more = flags & (MSG_SENDPAGE_NOTLAST | MSG_MORE);
409 struct tls_record_info *record = ctx->open_record;
410 int tls_push_record_flags;
411 struct page_frag *pfrag;
412 size_t orig_size = size;
413 u32 max_open_record_len;
414 int copy, rc = 0;
415 bool done = false;
416 long timeo;
417
418 if (flags &
419 ~(MSG_MORE | MSG_DONTWAIT | MSG_NOSIGNAL | MSG_SENDPAGE_NOTLAST))
420 return -EOPNOTSUPP;
421
422 if (sk->sk_err)
423 return -sk->sk_err;
424
425 flags |= MSG_SENDPAGE_DECRYPTED;
426 tls_push_record_flags = flags | MSG_SENDPAGE_NOTLAST;
427
428 timeo = sock_sndtimeo(sk, flags & MSG_DONTWAIT);
429 if (tls_is_partially_sent_record(tls_ctx)) {
430 rc = tls_push_partial_record(sk, tls_ctx, flags);
431 if (rc < 0)
432 return rc;
433 }
434
435 pfrag = sk_page_frag(sk);
436
437 /* TLS_HEADER_SIZE is not counted as part of the TLS record, and
438 * we need to leave room for an authentication tag.
439 */
440 max_open_record_len = TLS_MAX_PAYLOAD_SIZE +
441 prot->prepend_size;
442 do {
443 rc = tls_do_allocation(sk, ctx, pfrag,
444 prot->prepend_size);
445 if (rc) {
446 rc = sk_stream_wait_memory(sk, &timeo);
447 if (!rc)
448 continue;
449
450 record = ctx->open_record;
451 if (!record)
452 break;
453 handle_error:
454 if (record_type != TLS_RECORD_TYPE_DATA) {
455 /* avoid sending partial
456 * record with type !=
457 * application_data
458 */
459 size = orig_size;
460 destroy_record(record);
461 ctx->open_record = NULL;
462 } else if (record->len > prot->prepend_size) {
463 goto last_record;
464 }
465
466 break;
467 }
468
469 record = ctx->open_record;
470 copy = min_t(size_t, size, (pfrag->size - pfrag->offset));
471 copy = min_t(size_t, copy, (max_open_record_len - record->len));
472
473 rc = tls_device_copy_data(page_address(pfrag->page) +
474 pfrag->offset, copy, msg_iter);
475 if (rc)
476 goto handle_error;
477 tls_append_frag(record, pfrag, copy);
478
479 size -= copy;
480 if (!size) {
481 last_record:
482 tls_push_record_flags = flags;
483 if (more) {
484 tls_ctx->pending_open_record_frags =
485 !!record->num_frags;
486 break;
487 }
488
489 done = true;
490 }
491
492 if (done || record->len >= max_open_record_len ||
493 (record->num_frags >= MAX_SKB_FRAGS - 1)) {
494 rc = tls_device_record_close(sk, tls_ctx, record,
495 pfrag, record_type);
496 if (rc) {
497 if (rc > 0) {
498 size += rc;
499 } else {
500 size = orig_size;
501 destroy_record(record);
502 ctx->open_record = NULL;
503 break;
504 }
505 }
506
507 rc = tls_push_record(sk,
508 tls_ctx,
509 ctx,
510 record,
511 tls_push_record_flags);
512 if (rc < 0)
513 break;
514 }
515 } while (!done);
516
517 if (orig_size - size > 0)
518 rc = orig_size - size;
519
520 return rc;
521 }
522
tls_device_sendmsg(struct sock * sk,struct msghdr * msg,size_t size)523 int tls_device_sendmsg(struct sock *sk, struct msghdr *msg, size_t size)
524 {
525 unsigned char record_type = TLS_RECORD_TYPE_DATA;
526 struct tls_context *tls_ctx = tls_get_ctx(sk);
527 int rc;
528
529 mutex_lock(&tls_ctx->tx_lock);
530 lock_sock(sk);
531
532 if (unlikely(msg->msg_controllen)) {
533 rc = tls_proccess_cmsg(sk, msg, &record_type);
534 if (rc)
535 goto out;
536 }
537
538 rc = tls_push_data(sk, &msg->msg_iter, size,
539 msg->msg_flags, record_type);
540
541 out:
542 release_sock(sk);
543 mutex_unlock(&tls_ctx->tx_lock);
544 return rc;
545 }
546
tls_device_sendpage(struct sock * sk,struct page * page,int offset,size_t size,int flags)547 int tls_device_sendpage(struct sock *sk, struct page *page,
548 int offset, size_t size, int flags)
549 {
550 struct tls_context *tls_ctx = tls_get_ctx(sk);
551 struct iov_iter msg_iter;
552 char *kaddr = kmap(page);
553 struct kvec iov;
554 int rc;
555
556 if (flags & MSG_SENDPAGE_NOTLAST)
557 flags |= MSG_MORE;
558
559 mutex_lock(&tls_ctx->tx_lock);
560 lock_sock(sk);
561
562 if (flags & MSG_OOB) {
563 rc = -EOPNOTSUPP;
564 goto out;
565 }
566
567 iov.iov_base = kaddr + offset;
568 iov.iov_len = size;
569 iov_iter_kvec(&msg_iter, WRITE, &iov, 1, size);
570 rc = tls_push_data(sk, &msg_iter, size,
571 flags, TLS_RECORD_TYPE_DATA);
572 kunmap(page);
573
574 out:
575 release_sock(sk);
576 mutex_unlock(&tls_ctx->tx_lock);
577 return rc;
578 }
579
tls_get_record(struct tls_offload_context_tx * context,u32 seq,u64 * p_record_sn)580 struct tls_record_info *tls_get_record(struct tls_offload_context_tx *context,
581 u32 seq, u64 *p_record_sn)
582 {
583 u64 record_sn = context->hint_record_sn;
584 struct tls_record_info *info;
585
586 info = context->retransmit_hint;
587 if (!info ||
588 before(seq, info->end_seq - info->len)) {
589 /* if retransmit_hint is irrelevant start
590 * from the beggining of the list
591 */
592 info = list_first_entry_or_null(&context->records_list,
593 struct tls_record_info, list);
594 if (!info)
595 return NULL;
596 record_sn = context->unacked_record_sn;
597 }
598
599 /* We just need the _rcu for the READ_ONCE() */
600 rcu_read_lock();
601 list_for_each_entry_from_rcu(info, &context->records_list, list) {
602 if (before(seq, info->end_seq)) {
603 if (!context->retransmit_hint ||
604 after(info->end_seq,
605 context->retransmit_hint->end_seq)) {
606 context->hint_record_sn = record_sn;
607 context->retransmit_hint = info;
608 }
609 *p_record_sn = record_sn;
610 goto exit_rcu_unlock;
611 }
612 record_sn++;
613 }
614 info = NULL;
615
616 exit_rcu_unlock:
617 rcu_read_unlock();
618 return info;
619 }
620 EXPORT_SYMBOL(tls_get_record);
621
tls_device_push_pending_record(struct sock * sk,int flags)622 static int tls_device_push_pending_record(struct sock *sk, int flags)
623 {
624 struct iov_iter msg_iter;
625
626 iov_iter_kvec(&msg_iter, WRITE, NULL, 0, 0);
627 return tls_push_data(sk, &msg_iter, 0, flags, TLS_RECORD_TYPE_DATA);
628 }
629
tls_device_write_space(struct sock * sk,struct tls_context * ctx)630 void tls_device_write_space(struct sock *sk, struct tls_context *ctx)
631 {
632 if (tls_is_partially_sent_record(ctx)) {
633 gfp_t sk_allocation = sk->sk_allocation;
634
635 WARN_ON_ONCE(sk->sk_write_pending);
636
637 sk->sk_allocation = GFP_ATOMIC;
638 tls_push_partial_record(sk, ctx,
639 MSG_DONTWAIT | MSG_NOSIGNAL |
640 MSG_SENDPAGE_DECRYPTED);
641 sk->sk_allocation = sk_allocation;
642 }
643 }
644
tls_device_resync_rx(struct tls_context * tls_ctx,struct sock * sk,u32 seq,u8 * rcd_sn)645 static void tls_device_resync_rx(struct tls_context *tls_ctx,
646 struct sock *sk, u32 seq, u8 *rcd_sn)
647 {
648 struct net_device *netdev;
649
650 if (WARN_ON(test_and_set_bit(TLS_RX_SYNC_RUNNING, &tls_ctx->flags)))
651 return;
652 netdev = READ_ONCE(tls_ctx->netdev);
653 if (netdev)
654 netdev->tlsdev_ops->tls_dev_resync(netdev, sk, seq, rcd_sn,
655 TLS_OFFLOAD_CTX_DIR_RX);
656 clear_bit_unlock(TLS_RX_SYNC_RUNNING, &tls_ctx->flags);
657 }
658
tls_device_rx_resync_new_rec(struct sock * sk,u32 rcd_len,u32 seq)659 void tls_device_rx_resync_new_rec(struct sock *sk, u32 rcd_len, u32 seq)
660 {
661 struct tls_context *tls_ctx = tls_get_ctx(sk);
662 struct tls_offload_context_rx *rx_ctx;
663 u8 rcd_sn[TLS_MAX_REC_SEQ_SIZE];
664 struct tls_prot_info *prot;
665 u32 is_req_pending;
666 s64 resync_req;
667 u32 req_seq;
668
669 if (tls_ctx->rx_conf != TLS_HW)
670 return;
671
672 prot = &tls_ctx->prot_info;
673 rx_ctx = tls_offload_ctx_rx(tls_ctx);
674 memcpy(rcd_sn, tls_ctx->rx.rec_seq, prot->rec_seq_size);
675
676 switch (rx_ctx->resync_type) {
677 case TLS_OFFLOAD_SYNC_TYPE_DRIVER_REQ:
678 resync_req = atomic64_read(&rx_ctx->resync_req);
679 req_seq = resync_req >> 32;
680 seq += TLS_HEADER_SIZE - 1;
681 is_req_pending = resync_req;
682
683 if (likely(!is_req_pending) || req_seq != seq ||
684 !atomic64_try_cmpxchg(&rx_ctx->resync_req, &resync_req, 0))
685 return;
686 break;
687 case TLS_OFFLOAD_SYNC_TYPE_CORE_NEXT_HINT:
688 if (likely(!rx_ctx->resync_nh_do_now))
689 return;
690
691 /* head of next rec is already in, note that the sock_inq will
692 * include the currently parsed message when called from parser
693 */
694 if (tcp_inq(sk) > rcd_len)
695 return;
696
697 rx_ctx->resync_nh_do_now = 0;
698 seq += rcd_len;
699 tls_bigint_increment(rcd_sn, prot->rec_seq_size);
700 break;
701 }
702
703 tls_device_resync_rx(tls_ctx, sk, seq, rcd_sn);
704 }
705
tls_device_core_ctrl_rx_resync(struct tls_context * tls_ctx,struct tls_offload_context_rx * ctx,struct sock * sk,struct sk_buff * skb)706 static void tls_device_core_ctrl_rx_resync(struct tls_context *tls_ctx,
707 struct tls_offload_context_rx *ctx,
708 struct sock *sk, struct sk_buff *skb)
709 {
710 struct strp_msg *rxm;
711
712 /* device will request resyncs by itself based on stream scan */
713 if (ctx->resync_type != TLS_OFFLOAD_SYNC_TYPE_CORE_NEXT_HINT)
714 return;
715 /* already scheduled */
716 if (ctx->resync_nh_do_now)
717 return;
718 /* seen decrypted fragments since last fully-failed record */
719 if (ctx->resync_nh_reset) {
720 ctx->resync_nh_reset = 0;
721 ctx->resync_nh.decrypted_failed = 1;
722 ctx->resync_nh.decrypted_tgt = TLS_DEVICE_RESYNC_NH_START_IVAL;
723 return;
724 }
725
726 if (++ctx->resync_nh.decrypted_failed <= ctx->resync_nh.decrypted_tgt)
727 return;
728
729 /* doing resync, bump the next target in case it fails */
730 if (ctx->resync_nh.decrypted_tgt < TLS_DEVICE_RESYNC_NH_MAX_IVAL)
731 ctx->resync_nh.decrypted_tgt *= 2;
732 else
733 ctx->resync_nh.decrypted_tgt += TLS_DEVICE_RESYNC_NH_MAX_IVAL;
734
735 rxm = strp_msg(skb);
736
737 /* head of next rec is already in, parser will sync for us */
738 if (tcp_inq(sk) > rxm->full_len) {
739 ctx->resync_nh_do_now = 1;
740 } else {
741 struct tls_prot_info *prot = &tls_ctx->prot_info;
742 u8 rcd_sn[TLS_MAX_REC_SEQ_SIZE];
743
744 memcpy(rcd_sn, tls_ctx->rx.rec_seq, prot->rec_seq_size);
745 tls_bigint_increment(rcd_sn, prot->rec_seq_size);
746
747 tls_device_resync_rx(tls_ctx, sk, tcp_sk(sk)->copied_seq,
748 rcd_sn);
749 }
750 }
751
tls_device_reencrypt(struct sock * sk,struct sk_buff * skb)752 static int tls_device_reencrypt(struct sock *sk, struct sk_buff *skb)
753 {
754 struct strp_msg *rxm = strp_msg(skb);
755 int err = 0, offset = rxm->offset, copy, nsg, data_len, pos;
756 struct sk_buff *skb_iter, *unused;
757 struct scatterlist sg[1];
758 char *orig_buf, *buf;
759
760 orig_buf = kmalloc(rxm->full_len + TLS_HEADER_SIZE +
761 TLS_CIPHER_AES_GCM_128_IV_SIZE, sk->sk_allocation);
762 if (!orig_buf)
763 return -ENOMEM;
764 buf = orig_buf;
765
766 nsg = skb_cow_data(skb, 0, &unused);
767 if (unlikely(nsg < 0)) {
768 err = nsg;
769 goto free_buf;
770 }
771
772 sg_init_table(sg, 1);
773 sg_set_buf(&sg[0], buf,
774 rxm->full_len + TLS_HEADER_SIZE +
775 TLS_CIPHER_AES_GCM_128_IV_SIZE);
776 err = skb_copy_bits(skb, offset, buf,
777 TLS_HEADER_SIZE + TLS_CIPHER_AES_GCM_128_IV_SIZE);
778 if (err)
779 goto free_buf;
780
781 /* We are interested only in the decrypted data not the auth */
782 err = decrypt_skb(sk, skb, sg);
783 if (err != -EBADMSG)
784 goto free_buf;
785 else
786 err = 0;
787
788 data_len = rxm->full_len - TLS_CIPHER_AES_GCM_128_TAG_SIZE;
789
790 if (skb_pagelen(skb) > offset) {
791 copy = min_t(int, skb_pagelen(skb) - offset, data_len);
792
793 if (skb->decrypted) {
794 err = skb_store_bits(skb, offset, buf, copy);
795 if (err)
796 goto free_buf;
797 }
798
799 offset += copy;
800 buf += copy;
801 }
802
803 pos = skb_pagelen(skb);
804 skb_walk_frags(skb, skb_iter) {
805 int frag_pos;
806
807 /* Practically all frags must belong to msg if reencrypt
808 * is needed with current strparser and coalescing logic,
809 * but strparser may "get optimized", so let's be safe.
810 */
811 if (pos + skb_iter->len <= offset)
812 goto done_with_frag;
813 if (pos >= data_len + rxm->offset)
814 break;
815
816 frag_pos = offset - pos;
817 copy = min_t(int, skb_iter->len - frag_pos,
818 data_len + rxm->offset - offset);
819
820 if (skb_iter->decrypted) {
821 err = skb_store_bits(skb_iter, frag_pos, buf, copy);
822 if (err)
823 goto free_buf;
824 }
825
826 offset += copy;
827 buf += copy;
828 done_with_frag:
829 pos += skb_iter->len;
830 }
831
832 free_buf:
833 kfree(orig_buf);
834 return err;
835 }
836
tls_device_decrypted(struct sock * sk,struct sk_buff * skb)837 int tls_device_decrypted(struct sock *sk, struct sk_buff *skb)
838 {
839 struct tls_context *tls_ctx = tls_get_ctx(sk);
840 struct tls_offload_context_rx *ctx = tls_offload_ctx_rx(tls_ctx);
841 int is_decrypted = skb->decrypted;
842 int is_encrypted = !is_decrypted;
843 struct sk_buff *skb_iter;
844
845 /* Check if all the data is decrypted already */
846 skb_walk_frags(skb, skb_iter) {
847 is_decrypted &= skb_iter->decrypted;
848 is_encrypted &= !skb_iter->decrypted;
849 }
850
851 ctx->sw.decrypted |= is_decrypted;
852
853 /* Return immediately if the record is either entirely plaintext or
854 * entirely ciphertext. Otherwise handle reencrypt partially decrypted
855 * record.
856 */
857 if (is_decrypted) {
858 ctx->resync_nh_reset = 1;
859 return 0;
860 }
861 if (is_encrypted) {
862 tls_device_core_ctrl_rx_resync(tls_ctx, ctx, sk, skb);
863 return 0;
864 }
865
866 ctx->resync_nh_reset = 1;
867 return tls_device_reencrypt(sk, skb);
868 }
869
tls_device_attach(struct tls_context * ctx,struct sock * sk,struct net_device * netdev)870 static void tls_device_attach(struct tls_context *ctx, struct sock *sk,
871 struct net_device *netdev)
872 {
873 if (sk->sk_destruct != tls_device_sk_destruct) {
874 refcount_set(&ctx->refcount, 1);
875 dev_hold(netdev);
876 ctx->netdev = netdev;
877 spin_lock_irq(&tls_device_lock);
878 list_add_tail(&ctx->list, &tls_device_list);
879 spin_unlock_irq(&tls_device_lock);
880
881 ctx->sk_destruct = sk->sk_destruct;
882 sk->sk_destruct = tls_device_sk_destruct;
883 }
884 }
885
tls_set_device_offload(struct sock * sk,struct tls_context * ctx)886 int tls_set_device_offload(struct sock *sk, struct tls_context *ctx)
887 {
888 u16 nonce_size, tag_size, iv_size, rec_seq_size;
889 struct tls_context *tls_ctx = tls_get_ctx(sk);
890 struct tls_prot_info *prot = &tls_ctx->prot_info;
891 struct tls_record_info *start_marker_record;
892 struct tls_offload_context_tx *offload_ctx;
893 struct tls_crypto_info *crypto_info;
894 struct net_device *netdev;
895 char *iv, *rec_seq;
896 struct sk_buff *skb;
897 __be64 rcd_sn;
898 int rc;
899
900 if (!ctx)
901 return -EINVAL;
902
903 if (ctx->priv_ctx_tx)
904 return -EEXIST;
905
906 start_marker_record = kmalloc(sizeof(*start_marker_record), GFP_KERNEL);
907 if (!start_marker_record)
908 return -ENOMEM;
909
910 offload_ctx = kzalloc(TLS_OFFLOAD_CONTEXT_SIZE_TX, GFP_KERNEL);
911 if (!offload_ctx) {
912 rc = -ENOMEM;
913 goto free_marker_record;
914 }
915
916 crypto_info = &ctx->crypto_send.info;
917 if (crypto_info->version != TLS_1_2_VERSION) {
918 rc = -EOPNOTSUPP;
919 goto free_offload_ctx;
920 }
921
922 switch (crypto_info->cipher_type) {
923 case TLS_CIPHER_AES_GCM_128:
924 nonce_size = TLS_CIPHER_AES_GCM_128_IV_SIZE;
925 tag_size = TLS_CIPHER_AES_GCM_128_TAG_SIZE;
926 iv_size = TLS_CIPHER_AES_GCM_128_IV_SIZE;
927 iv = ((struct tls12_crypto_info_aes_gcm_128 *)crypto_info)->iv;
928 rec_seq_size = TLS_CIPHER_AES_GCM_128_REC_SEQ_SIZE;
929 rec_seq =
930 ((struct tls12_crypto_info_aes_gcm_128 *)crypto_info)->rec_seq;
931 break;
932 default:
933 rc = -EINVAL;
934 goto free_offload_ctx;
935 }
936
937 /* Sanity-check the rec_seq_size for stack allocations */
938 if (rec_seq_size > TLS_MAX_REC_SEQ_SIZE) {
939 rc = -EINVAL;
940 goto free_offload_ctx;
941 }
942
943 prot->version = crypto_info->version;
944 prot->cipher_type = crypto_info->cipher_type;
945 prot->prepend_size = TLS_HEADER_SIZE + nonce_size;
946 prot->tag_size = tag_size;
947 prot->overhead_size = prot->prepend_size + prot->tag_size;
948 prot->iv_size = iv_size;
949 ctx->tx.iv = kmalloc(iv_size + TLS_CIPHER_AES_GCM_128_SALT_SIZE,
950 GFP_KERNEL);
951 if (!ctx->tx.iv) {
952 rc = -ENOMEM;
953 goto free_offload_ctx;
954 }
955
956 memcpy(ctx->tx.iv + TLS_CIPHER_AES_GCM_128_SALT_SIZE, iv, iv_size);
957
958 prot->rec_seq_size = rec_seq_size;
959 ctx->tx.rec_seq = kmemdup(rec_seq, rec_seq_size, GFP_KERNEL);
960 if (!ctx->tx.rec_seq) {
961 rc = -ENOMEM;
962 goto free_iv;
963 }
964
965 rc = tls_sw_fallback_init(sk, offload_ctx, crypto_info);
966 if (rc)
967 goto free_rec_seq;
968
969 /* start at rec_seq - 1 to account for the start marker record */
970 memcpy(&rcd_sn, ctx->tx.rec_seq, sizeof(rcd_sn));
971 offload_ctx->unacked_record_sn = be64_to_cpu(rcd_sn) - 1;
972
973 start_marker_record->end_seq = tcp_sk(sk)->write_seq;
974 start_marker_record->len = 0;
975 start_marker_record->num_frags = 0;
976
977 INIT_LIST_HEAD(&offload_ctx->records_list);
978 list_add_tail(&start_marker_record->list, &offload_ctx->records_list);
979 spin_lock_init(&offload_ctx->lock);
980 sg_init_table(offload_ctx->sg_tx_data,
981 ARRAY_SIZE(offload_ctx->sg_tx_data));
982
983 clean_acked_data_enable(inet_csk(sk), &tls_icsk_clean_acked);
984 ctx->push_pending_record = tls_device_push_pending_record;
985
986 /* TLS offload is greatly simplified if we don't send
987 * SKBs where only part of the payload needs to be encrypted.
988 * So mark the last skb in the write queue as end of record.
989 */
990 skb = tcp_write_queue_tail(sk);
991 if (skb)
992 TCP_SKB_CB(skb)->eor = 1;
993
994 netdev = get_netdev_for_sock(sk);
995 if (!netdev) {
996 pr_err_ratelimited("%s: netdev not found\n", __func__);
997 rc = -EINVAL;
998 goto disable_cad;
999 }
1000
1001 if (!(netdev->features & NETIF_F_HW_TLS_TX)) {
1002 rc = -EOPNOTSUPP;
1003 goto release_netdev;
1004 }
1005
1006 /* Avoid offloading if the device is down
1007 * We don't want to offload new flows after
1008 * the NETDEV_DOWN event
1009 *
1010 * device_offload_lock is taken in tls_devices's NETDEV_DOWN
1011 * handler thus protecting from the device going down before
1012 * ctx was added to tls_device_list.
1013 */
1014 down_read(&device_offload_lock);
1015 if (!(netdev->flags & IFF_UP)) {
1016 rc = -EINVAL;
1017 goto release_lock;
1018 }
1019
1020 ctx->priv_ctx_tx = offload_ctx;
1021 rc = netdev->tlsdev_ops->tls_dev_add(netdev, sk, TLS_OFFLOAD_CTX_DIR_TX,
1022 &ctx->crypto_send.info,
1023 tcp_sk(sk)->write_seq);
1024 if (rc)
1025 goto release_lock;
1026
1027 tls_device_attach(ctx, sk, netdev);
1028 up_read(&device_offload_lock);
1029
1030 /* following this assignment tls_is_sk_tx_device_offloaded
1031 * will return true and the context might be accessed
1032 * by the netdev's xmit function.
1033 */
1034 smp_store_release(&sk->sk_validate_xmit_skb, tls_validate_xmit_skb);
1035 dev_put(netdev);
1036
1037 return 0;
1038
1039 release_lock:
1040 up_read(&device_offload_lock);
1041 release_netdev:
1042 dev_put(netdev);
1043 disable_cad:
1044 clean_acked_data_disable(inet_csk(sk));
1045 crypto_free_aead(offload_ctx->aead_send);
1046 free_rec_seq:
1047 kfree(ctx->tx.rec_seq);
1048 free_iv:
1049 kfree(ctx->tx.iv);
1050 free_offload_ctx:
1051 kfree(offload_ctx);
1052 ctx->priv_ctx_tx = NULL;
1053 free_marker_record:
1054 kfree(start_marker_record);
1055 return rc;
1056 }
1057
tls_set_device_offload_rx(struct sock * sk,struct tls_context * ctx)1058 int tls_set_device_offload_rx(struct sock *sk, struct tls_context *ctx)
1059 {
1060 struct tls_offload_context_rx *context;
1061 struct net_device *netdev;
1062 int rc = 0;
1063
1064 if (ctx->crypto_recv.info.version != TLS_1_2_VERSION)
1065 return -EOPNOTSUPP;
1066
1067 netdev = get_netdev_for_sock(sk);
1068 if (!netdev) {
1069 pr_err_ratelimited("%s: netdev not found\n", __func__);
1070 return -EINVAL;
1071 }
1072
1073 if (!(netdev->features & NETIF_F_HW_TLS_RX)) {
1074 rc = -EOPNOTSUPP;
1075 goto release_netdev;
1076 }
1077
1078 /* Avoid offloading if the device is down
1079 * We don't want to offload new flows after
1080 * the NETDEV_DOWN event
1081 *
1082 * device_offload_lock is taken in tls_devices's NETDEV_DOWN
1083 * handler thus protecting from the device going down before
1084 * ctx was added to tls_device_list.
1085 */
1086 down_read(&device_offload_lock);
1087 if (!(netdev->flags & IFF_UP)) {
1088 rc = -EINVAL;
1089 goto release_lock;
1090 }
1091
1092 context = kzalloc(TLS_OFFLOAD_CONTEXT_SIZE_RX, GFP_KERNEL);
1093 if (!context) {
1094 rc = -ENOMEM;
1095 goto release_lock;
1096 }
1097 context->resync_nh_reset = 1;
1098
1099 ctx->priv_ctx_rx = context;
1100 rc = tls_set_sw_offload(sk, ctx, 0);
1101 if (rc)
1102 goto release_ctx;
1103
1104 rc = netdev->tlsdev_ops->tls_dev_add(netdev, sk, TLS_OFFLOAD_CTX_DIR_RX,
1105 &ctx->crypto_recv.info,
1106 tcp_sk(sk)->copied_seq);
1107 if (rc)
1108 goto free_sw_resources;
1109
1110 tls_device_attach(ctx, sk, netdev);
1111 up_read(&device_offload_lock);
1112
1113 dev_put(netdev);
1114
1115 return 0;
1116
1117 free_sw_resources:
1118 up_read(&device_offload_lock);
1119 tls_sw_free_resources_rx(sk);
1120 down_read(&device_offload_lock);
1121 release_ctx:
1122 ctx->priv_ctx_rx = NULL;
1123 release_lock:
1124 up_read(&device_offload_lock);
1125 release_netdev:
1126 dev_put(netdev);
1127 return rc;
1128 }
1129
tls_device_offload_cleanup_rx(struct sock * sk)1130 void tls_device_offload_cleanup_rx(struct sock *sk)
1131 {
1132 struct tls_context *tls_ctx = tls_get_ctx(sk);
1133 struct net_device *netdev;
1134
1135 down_read(&device_offload_lock);
1136 netdev = tls_ctx->netdev;
1137 if (!netdev)
1138 goto out;
1139
1140 netdev->tlsdev_ops->tls_dev_del(netdev, tls_ctx,
1141 TLS_OFFLOAD_CTX_DIR_RX);
1142
1143 if (tls_ctx->tx_conf != TLS_HW) {
1144 dev_put(netdev);
1145 tls_ctx->netdev = NULL;
1146 }
1147 out:
1148 up_read(&device_offload_lock);
1149 tls_sw_release_resources_rx(sk);
1150 }
1151
tls_device_down(struct net_device * netdev)1152 static int tls_device_down(struct net_device *netdev)
1153 {
1154 struct tls_context *ctx, *tmp;
1155 unsigned long flags;
1156 LIST_HEAD(list);
1157
1158 /* Request a write lock to block new offload attempts */
1159 down_write(&device_offload_lock);
1160
1161 spin_lock_irqsave(&tls_device_lock, flags);
1162 list_for_each_entry_safe(ctx, tmp, &tls_device_list, list) {
1163 if (ctx->netdev != netdev ||
1164 !refcount_inc_not_zero(&ctx->refcount))
1165 continue;
1166
1167 list_move(&ctx->list, &list);
1168 }
1169 spin_unlock_irqrestore(&tls_device_lock, flags);
1170
1171 list_for_each_entry_safe(ctx, tmp, &list, list) {
1172 if (ctx->tx_conf == TLS_HW)
1173 netdev->tlsdev_ops->tls_dev_del(netdev, ctx,
1174 TLS_OFFLOAD_CTX_DIR_TX);
1175 if (ctx->rx_conf == TLS_HW)
1176 netdev->tlsdev_ops->tls_dev_del(netdev, ctx,
1177 TLS_OFFLOAD_CTX_DIR_RX);
1178 WRITE_ONCE(ctx->netdev, NULL);
1179 smp_mb__before_atomic(); /* pairs with test_and_set_bit() */
1180 while (test_bit(TLS_RX_SYNC_RUNNING, &ctx->flags))
1181 usleep_range(10, 200);
1182 dev_put(netdev);
1183 list_del_init(&ctx->list);
1184
1185 if (refcount_dec_and_test(&ctx->refcount))
1186 tls_device_free_ctx(ctx);
1187 }
1188
1189 up_write(&device_offload_lock);
1190
1191 flush_work(&tls_device_gc_work);
1192
1193 return NOTIFY_DONE;
1194 }
1195
tls_dev_event(struct notifier_block * this,unsigned long event,void * ptr)1196 static int tls_dev_event(struct notifier_block *this, unsigned long event,
1197 void *ptr)
1198 {
1199 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
1200
1201 if (!dev->tlsdev_ops &&
1202 !(dev->features & (NETIF_F_HW_TLS_RX | NETIF_F_HW_TLS_TX)))
1203 return NOTIFY_DONE;
1204
1205 switch (event) {
1206 case NETDEV_REGISTER:
1207 case NETDEV_FEAT_CHANGE:
1208 if ((dev->features & NETIF_F_HW_TLS_RX) &&
1209 !dev->tlsdev_ops->tls_dev_resync)
1210 return NOTIFY_BAD;
1211
1212 if (dev->tlsdev_ops &&
1213 dev->tlsdev_ops->tls_dev_add &&
1214 dev->tlsdev_ops->tls_dev_del)
1215 return NOTIFY_DONE;
1216 else
1217 return NOTIFY_BAD;
1218 case NETDEV_DOWN:
1219 return tls_device_down(dev);
1220 }
1221 return NOTIFY_DONE;
1222 }
1223
1224 static struct notifier_block tls_dev_notifier = {
1225 .notifier_call = tls_dev_event,
1226 };
1227
tls_device_init(void)1228 void __init tls_device_init(void)
1229 {
1230 register_netdevice_notifier(&tls_dev_notifier);
1231 }
1232
tls_device_cleanup(void)1233 void __exit tls_device_cleanup(void)
1234 {
1235 unregister_netdevice_notifier(&tls_dev_notifier);
1236 flush_work(&tls_device_gc_work);
1237 clean_acked_data_flush();
1238 }
1239