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 #include "trace.h"
42
43 /* device_offload_lock is used to synchronize tls_dev_add
44 * against NETDEV_DOWN notifications.
45 */
46 static DECLARE_RWSEM(device_offload_lock);
47
48 static void tls_device_gc_task(struct work_struct *work);
49
50 static DECLARE_WORK(tls_device_gc_work, tls_device_gc_task);
51 static LIST_HEAD(tls_device_gc_list);
52 static LIST_HEAD(tls_device_list);
53 static LIST_HEAD(tls_device_down_list);
54 static DEFINE_SPINLOCK(tls_device_lock);
55
tls_device_free_ctx(struct tls_context * ctx)56 static void tls_device_free_ctx(struct tls_context *ctx)
57 {
58 if (ctx->tx_conf == TLS_HW) {
59 kfree(tls_offload_ctx_tx(ctx));
60 kfree(ctx->tx.rec_seq);
61 kfree(ctx->tx.iv);
62 }
63
64 if (ctx->rx_conf == TLS_HW)
65 kfree(tls_offload_ctx_rx(ctx));
66
67 tls_ctx_free(NULL, ctx);
68 }
69
tls_device_gc_task(struct work_struct * work)70 static void tls_device_gc_task(struct work_struct *work)
71 {
72 struct tls_context *ctx, *tmp;
73 unsigned long flags;
74 LIST_HEAD(gc_list);
75
76 spin_lock_irqsave(&tls_device_lock, flags);
77 list_splice_init(&tls_device_gc_list, &gc_list);
78 spin_unlock_irqrestore(&tls_device_lock, flags);
79
80 list_for_each_entry_safe(ctx, tmp, &gc_list, list) {
81 struct net_device *netdev = ctx->netdev;
82
83 if (netdev && ctx->tx_conf == TLS_HW) {
84 netdev->tlsdev_ops->tls_dev_del(netdev, ctx,
85 TLS_OFFLOAD_CTX_DIR_TX);
86 dev_put(netdev);
87 ctx->netdev = NULL;
88 }
89
90 list_del(&ctx->list);
91 tls_device_free_ctx(ctx);
92 }
93 }
94
tls_device_queue_ctx_destruction(struct tls_context * ctx)95 static void tls_device_queue_ctx_destruction(struct tls_context *ctx)
96 {
97 unsigned long flags;
98
99 spin_lock_irqsave(&tls_device_lock, flags);
100 list_move_tail(&ctx->list, &tls_device_gc_list);
101
102 /* schedule_work inside the spinlock
103 * to make sure tls_device_down waits for that work.
104 */
105 schedule_work(&tls_device_gc_work);
106
107 spin_unlock_irqrestore(&tls_device_lock, flags);
108 }
109
110 /* We assume that the socket is already connected */
get_netdev_for_sock(struct sock * sk)111 static struct net_device *get_netdev_for_sock(struct sock *sk)
112 {
113 struct dst_entry *dst = sk_dst_get(sk);
114 struct net_device *netdev = NULL;
115
116 if (likely(dst)) {
117 netdev = dst->dev;
118 dev_hold(netdev);
119 }
120
121 dst_release(dst);
122
123 return netdev;
124 }
125
destroy_record(struct tls_record_info * record)126 static void destroy_record(struct tls_record_info *record)
127 {
128 int i;
129
130 for (i = 0; i < record->num_frags; i++)
131 __skb_frag_unref(&record->frags[i]);
132 kfree(record);
133 }
134
delete_all_records(struct tls_offload_context_tx * offload_ctx)135 static void delete_all_records(struct tls_offload_context_tx *offload_ctx)
136 {
137 struct tls_record_info *info, *temp;
138
139 list_for_each_entry_safe(info, temp, &offload_ctx->records_list, list) {
140 list_del(&info->list);
141 destroy_record(info);
142 }
143
144 offload_ctx->retransmit_hint = NULL;
145 }
146
tls_icsk_clean_acked(struct sock * sk,u32 acked_seq)147 static void tls_icsk_clean_acked(struct sock *sk, u32 acked_seq)
148 {
149 struct tls_context *tls_ctx = tls_get_ctx(sk);
150 struct tls_record_info *info, *temp;
151 struct tls_offload_context_tx *ctx;
152 u64 deleted_records = 0;
153 unsigned long flags;
154
155 if (!tls_ctx)
156 return;
157
158 ctx = tls_offload_ctx_tx(tls_ctx);
159
160 spin_lock_irqsave(&ctx->lock, flags);
161 info = ctx->retransmit_hint;
162 if (info && !before(acked_seq, info->end_seq))
163 ctx->retransmit_hint = NULL;
164
165 list_for_each_entry_safe(info, temp, &ctx->records_list, list) {
166 if (before(acked_seq, info->end_seq))
167 break;
168 list_del(&info->list);
169
170 destroy_record(info);
171 deleted_records++;
172 }
173
174 ctx->unacked_record_sn += deleted_records;
175 spin_unlock_irqrestore(&ctx->lock, flags);
176 }
177
178 /* At this point, there should be no references on this
179 * socket and no in-flight SKBs associated with this
180 * socket, so it is safe to free all the resources.
181 */
tls_device_sk_destruct(struct sock * sk)182 void tls_device_sk_destruct(struct sock *sk)
183 {
184 struct tls_context *tls_ctx = tls_get_ctx(sk);
185 struct tls_offload_context_tx *ctx = tls_offload_ctx_tx(tls_ctx);
186
187 tls_ctx->sk_destruct(sk);
188
189 if (tls_ctx->tx_conf == TLS_HW) {
190 if (ctx->open_record)
191 destroy_record(ctx->open_record);
192 delete_all_records(ctx);
193 crypto_free_aead(ctx->aead_send);
194 clean_acked_data_disable(inet_csk(sk));
195 }
196
197 if (refcount_dec_and_test(&tls_ctx->refcount))
198 tls_device_queue_ctx_destruction(tls_ctx);
199 }
200 EXPORT_SYMBOL_GPL(tls_device_sk_destruct);
201
tls_device_free_resources_tx(struct sock * sk)202 void tls_device_free_resources_tx(struct sock *sk)
203 {
204 struct tls_context *tls_ctx = tls_get_ctx(sk);
205
206 tls_free_partial_record(sk, tls_ctx);
207 }
208
tls_offload_tx_resync_request(struct sock * sk,u32 got_seq,u32 exp_seq)209 void tls_offload_tx_resync_request(struct sock *sk, u32 got_seq, u32 exp_seq)
210 {
211 struct tls_context *tls_ctx = tls_get_ctx(sk);
212
213 trace_tls_device_tx_resync_req(sk, got_seq, exp_seq);
214 WARN_ON(test_and_set_bit(TLS_TX_SYNC_SCHED, &tls_ctx->flags));
215 }
216 EXPORT_SYMBOL_GPL(tls_offload_tx_resync_request);
217
tls_device_resync_tx(struct sock * sk,struct tls_context * tls_ctx,u32 seq)218 static void tls_device_resync_tx(struct sock *sk, struct tls_context *tls_ctx,
219 u32 seq)
220 {
221 struct net_device *netdev;
222 struct sk_buff *skb;
223 int err = 0;
224 u8 *rcd_sn;
225
226 skb = tcp_write_queue_tail(sk);
227 if (skb)
228 TCP_SKB_CB(skb)->eor = 1;
229
230 rcd_sn = tls_ctx->tx.rec_seq;
231
232 trace_tls_device_tx_resync_send(sk, seq, rcd_sn);
233 down_read(&device_offload_lock);
234 netdev = tls_ctx->netdev;
235 if (netdev)
236 err = netdev->tlsdev_ops->tls_dev_resync(netdev, sk, seq,
237 rcd_sn,
238 TLS_OFFLOAD_CTX_DIR_TX);
239 up_read(&device_offload_lock);
240 if (err)
241 return;
242
243 clear_bit_unlock(TLS_TX_SYNC_SCHED, &tls_ctx->flags);
244 }
245
tls_append_frag(struct tls_record_info * record,struct page_frag * pfrag,int size)246 static void tls_append_frag(struct tls_record_info *record,
247 struct page_frag *pfrag,
248 int size)
249 {
250 skb_frag_t *frag;
251
252 frag = &record->frags[record->num_frags - 1];
253 if (skb_frag_page(frag) == pfrag->page &&
254 skb_frag_off(frag) + skb_frag_size(frag) == pfrag->offset) {
255 skb_frag_size_add(frag, size);
256 } else {
257 ++frag;
258 __skb_frag_set_page(frag, pfrag->page);
259 skb_frag_off_set(frag, pfrag->offset);
260 skb_frag_size_set(frag, size);
261 ++record->num_frags;
262 get_page(pfrag->page);
263 }
264
265 pfrag->offset += size;
266 record->len += size;
267 }
268
tls_push_record(struct sock * sk,struct tls_context * ctx,struct tls_offload_context_tx * offload_ctx,struct tls_record_info * record,int flags)269 static int tls_push_record(struct sock *sk,
270 struct tls_context *ctx,
271 struct tls_offload_context_tx *offload_ctx,
272 struct tls_record_info *record,
273 int flags)
274 {
275 struct tls_prot_info *prot = &ctx->prot_info;
276 struct tcp_sock *tp = tcp_sk(sk);
277 skb_frag_t *frag;
278 int i;
279
280 record->end_seq = tp->write_seq + record->len;
281 list_add_tail_rcu(&record->list, &offload_ctx->records_list);
282 offload_ctx->open_record = NULL;
283
284 if (test_bit(TLS_TX_SYNC_SCHED, &ctx->flags))
285 tls_device_resync_tx(sk, ctx, tp->write_seq);
286
287 tls_advance_record_sn(sk, prot, &ctx->tx);
288
289 for (i = 0; i < record->num_frags; i++) {
290 frag = &record->frags[i];
291 sg_unmark_end(&offload_ctx->sg_tx_data[i]);
292 sg_set_page(&offload_ctx->sg_tx_data[i], skb_frag_page(frag),
293 skb_frag_size(frag), skb_frag_off(frag));
294 sk_mem_charge(sk, skb_frag_size(frag));
295 get_page(skb_frag_page(frag));
296 }
297 sg_mark_end(&offload_ctx->sg_tx_data[record->num_frags - 1]);
298
299 /* all ready, send */
300 return tls_push_sg(sk, ctx, offload_ctx->sg_tx_data, 0, flags);
301 }
302
tls_device_record_close(struct sock * sk,struct tls_context * ctx,struct tls_record_info * record,struct page_frag * pfrag,unsigned char record_type)303 static int tls_device_record_close(struct sock *sk,
304 struct tls_context *ctx,
305 struct tls_record_info *record,
306 struct page_frag *pfrag,
307 unsigned char record_type)
308 {
309 struct tls_prot_info *prot = &ctx->prot_info;
310 int ret;
311
312 /* append tag
313 * device will fill in the tag, we just need to append a placeholder
314 * use socket memory to improve coalescing (re-using a single buffer
315 * increases frag count)
316 * if we can't allocate memory now, steal some back from data
317 */
318 if (likely(skb_page_frag_refill(prot->tag_size, pfrag,
319 sk->sk_allocation))) {
320 ret = 0;
321 tls_append_frag(record, pfrag, prot->tag_size);
322 } else {
323 ret = prot->tag_size;
324 if (record->len <= prot->overhead_size)
325 return -ENOMEM;
326 }
327
328 /* fill prepend */
329 tls_fill_prepend(ctx, skb_frag_address(&record->frags[0]),
330 record->len - prot->overhead_size,
331 record_type, prot->version);
332 return ret;
333 }
334
tls_create_new_record(struct tls_offload_context_tx * offload_ctx,struct page_frag * pfrag,size_t prepend_size)335 static int tls_create_new_record(struct tls_offload_context_tx *offload_ctx,
336 struct page_frag *pfrag,
337 size_t prepend_size)
338 {
339 struct tls_record_info *record;
340 skb_frag_t *frag;
341
342 record = kmalloc(sizeof(*record), GFP_KERNEL);
343 if (!record)
344 return -ENOMEM;
345
346 frag = &record->frags[0];
347 __skb_frag_set_page(frag, pfrag->page);
348 skb_frag_off_set(frag, pfrag->offset);
349 skb_frag_size_set(frag, prepend_size);
350
351 get_page(pfrag->page);
352 pfrag->offset += prepend_size;
353
354 record->num_frags = 1;
355 record->len = prepend_size;
356 offload_ctx->open_record = record;
357 return 0;
358 }
359
tls_do_allocation(struct sock * sk,struct tls_offload_context_tx * offload_ctx,struct page_frag * pfrag,size_t prepend_size)360 static int tls_do_allocation(struct sock *sk,
361 struct tls_offload_context_tx *offload_ctx,
362 struct page_frag *pfrag,
363 size_t prepend_size)
364 {
365 int ret;
366
367 if (!offload_ctx->open_record) {
368 if (unlikely(!skb_page_frag_refill(prepend_size, pfrag,
369 sk->sk_allocation))) {
370 READ_ONCE(sk->sk_prot)->enter_memory_pressure(sk);
371 sk_stream_moderate_sndbuf(sk);
372 return -ENOMEM;
373 }
374
375 ret = tls_create_new_record(offload_ctx, pfrag, prepend_size);
376 if (ret)
377 return ret;
378
379 if (pfrag->size > pfrag->offset)
380 return 0;
381 }
382
383 if (!sk_page_frag_refill(sk, pfrag))
384 return -ENOMEM;
385
386 return 0;
387 }
388
tls_device_copy_data(void * addr,size_t bytes,struct iov_iter * i)389 static int tls_device_copy_data(void *addr, size_t bytes, struct iov_iter *i)
390 {
391 size_t pre_copy, nocache;
392
393 pre_copy = ~((unsigned long)addr - 1) & (SMP_CACHE_BYTES - 1);
394 if (pre_copy) {
395 pre_copy = min(pre_copy, bytes);
396 if (copy_from_iter(addr, pre_copy, i) != pre_copy)
397 return -EFAULT;
398 bytes -= pre_copy;
399 addr += pre_copy;
400 }
401
402 nocache = round_down(bytes, SMP_CACHE_BYTES);
403 if (copy_from_iter_nocache(addr, nocache, i) != nocache)
404 return -EFAULT;
405 bytes -= nocache;
406 addr += nocache;
407
408 if (bytes && copy_from_iter(addr, bytes, i) != bytes)
409 return -EFAULT;
410
411 return 0;
412 }
413
tls_push_data(struct sock * sk,struct iov_iter * msg_iter,size_t size,int flags,unsigned char record_type)414 static int tls_push_data(struct sock *sk,
415 struct iov_iter *msg_iter,
416 size_t size, int flags,
417 unsigned char record_type)
418 {
419 struct tls_context *tls_ctx = tls_get_ctx(sk);
420 struct tls_prot_info *prot = &tls_ctx->prot_info;
421 struct tls_offload_context_tx *ctx = tls_offload_ctx_tx(tls_ctx);
422 struct tls_record_info *record = ctx->open_record;
423 int tls_push_record_flags;
424 struct page_frag *pfrag;
425 size_t orig_size = size;
426 u32 max_open_record_len;
427 bool more = false;
428 bool done = false;
429 int copy, rc = 0;
430 long timeo;
431
432 if (flags &
433 ~(MSG_MORE | MSG_DONTWAIT | MSG_NOSIGNAL | MSG_SENDPAGE_NOTLAST))
434 return -EOPNOTSUPP;
435
436 if (unlikely(sk->sk_err))
437 return -sk->sk_err;
438
439 flags |= MSG_SENDPAGE_DECRYPTED;
440 tls_push_record_flags = flags | MSG_SENDPAGE_NOTLAST;
441
442 timeo = sock_sndtimeo(sk, flags & MSG_DONTWAIT);
443 if (tls_is_partially_sent_record(tls_ctx)) {
444 rc = tls_push_partial_record(sk, tls_ctx, flags);
445 if (rc < 0)
446 return rc;
447 }
448
449 pfrag = sk_page_frag(sk);
450
451 /* TLS_HEADER_SIZE is not counted as part of the TLS record, and
452 * we need to leave room for an authentication tag.
453 */
454 max_open_record_len = TLS_MAX_PAYLOAD_SIZE +
455 prot->prepend_size;
456 do {
457 rc = tls_do_allocation(sk, ctx, pfrag, prot->prepend_size);
458 if (unlikely(rc)) {
459 rc = sk_stream_wait_memory(sk, &timeo);
460 if (!rc)
461 continue;
462
463 record = ctx->open_record;
464 if (!record)
465 break;
466 handle_error:
467 if (record_type != TLS_RECORD_TYPE_DATA) {
468 /* avoid sending partial
469 * record with type !=
470 * application_data
471 */
472 size = orig_size;
473 destroy_record(record);
474 ctx->open_record = NULL;
475 } else if (record->len > prot->prepend_size) {
476 goto last_record;
477 }
478
479 break;
480 }
481
482 record = ctx->open_record;
483 copy = min_t(size_t, size, (pfrag->size - pfrag->offset));
484 copy = min_t(size_t, copy, (max_open_record_len - record->len));
485
486 rc = tls_device_copy_data(page_address(pfrag->page) +
487 pfrag->offset, copy, msg_iter);
488 if (rc)
489 goto handle_error;
490 tls_append_frag(record, pfrag, copy);
491
492 size -= copy;
493 if (!size) {
494 last_record:
495 tls_push_record_flags = flags;
496 if (flags & (MSG_SENDPAGE_NOTLAST | MSG_MORE)) {
497 more = true;
498 break;
499 }
500
501 done = true;
502 }
503
504 if (done || record->len >= max_open_record_len ||
505 (record->num_frags >= MAX_SKB_FRAGS - 1)) {
506 rc = tls_device_record_close(sk, tls_ctx, record,
507 pfrag, record_type);
508 if (rc) {
509 if (rc > 0) {
510 size += rc;
511 } else {
512 size = orig_size;
513 destroy_record(record);
514 ctx->open_record = NULL;
515 break;
516 }
517 }
518
519 rc = tls_push_record(sk,
520 tls_ctx,
521 ctx,
522 record,
523 tls_push_record_flags);
524 if (rc < 0)
525 break;
526 }
527 } while (!done);
528
529 tls_ctx->pending_open_record_frags = more;
530
531 if (orig_size - size > 0)
532 rc = orig_size - size;
533
534 return rc;
535 }
536
tls_device_sendmsg(struct sock * sk,struct msghdr * msg,size_t size)537 int tls_device_sendmsg(struct sock *sk, struct msghdr *msg, size_t size)
538 {
539 unsigned char record_type = TLS_RECORD_TYPE_DATA;
540 struct tls_context *tls_ctx = tls_get_ctx(sk);
541 int rc;
542
543 mutex_lock(&tls_ctx->tx_lock);
544 lock_sock(sk);
545
546 if (unlikely(msg->msg_controllen)) {
547 rc = tls_proccess_cmsg(sk, msg, &record_type);
548 if (rc)
549 goto out;
550 }
551
552 rc = tls_push_data(sk, &msg->msg_iter, size,
553 msg->msg_flags, record_type);
554
555 out:
556 release_sock(sk);
557 mutex_unlock(&tls_ctx->tx_lock);
558 return rc;
559 }
560
tls_device_sendpage(struct sock * sk,struct page * page,int offset,size_t size,int flags)561 int tls_device_sendpage(struct sock *sk, struct page *page,
562 int offset, size_t size, int flags)
563 {
564 struct tls_context *tls_ctx = tls_get_ctx(sk);
565 struct iov_iter msg_iter;
566 char *kaddr;
567 struct kvec iov;
568 int rc;
569
570 if (flags & MSG_SENDPAGE_NOTLAST)
571 flags |= MSG_MORE;
572
573 mutex_lock(&tls_ctx->tx_lock);
574 lock_sock(sk);
575
576 if (flags & MSG_OOB) {
577 rc = -EOPNOTSUPP;
578 goto out;
579 }
580
581 kaddr = kmap(page);
582 iov.iov_base = kaddr + offset;
583 iov.iov_len = size;
584 iov_iter_kvec(&msg_iter, WRITE, &iov, 1, size);
585 rc = tls_push_data(sk, &msg_iter, size,
586 flags, TLS_RECORD_TYPE_DATA);
587 kunmap(page);
588
589 out:
590 release_sock(sk);
591 mutex_unlock(&tls_ctx->tx_lock);
592 return rc;
593 }
594
tls_get_record(struct tls_offload_context_tx * context,u32 seq,u64 * p_record_sn)595 struct tls_record_info *tls_get_record(struct tls_offload_context_tx *context,
596 u32 seq, u64 *p_record_sn)
597 {
598 u64 record_sn = context->hint_record_sn;
599 struct tls_record_info *info, *last;
600
601 info = context->retransmit_hint;
602 if (!info ||
603 before(seq, info->end_seq - info->len)) {
604 /* if retransmit_hint is irrelevant start
605 * from the beggining of the list
606 */
607 info = list_first_entry_or_null(&context->records_list,
608 struct tls_record_info, list);
609 if (!info)
610 return NULL;
611 /* send the start_marker record if seq number is before the
612 * tls offload start marker sequence number. This record is
613 * required to handle TCP packets which are before TLS offload
614 * started.
615 * And if it's not start marker, look if this seq number
616 * belongs to the list.
617 */
618 if (likely(!tls_record_is_start_marker(info))) {
619 /* we have the first record, get the last record to see
620 * if this seq number belongs to the list.
621 */
622 last = list_last_entry(&context->records_list,
623 struct tls_record_info, list);
624
625 if (!between(seq, tls_record_start_seq(info),
626 last->end_seq))
627 return NULL;
628 }
629 record_sn = context->unacked_record_sn;
630 }
631
632 /* We just need the _rcu for the READ_ONCE() */
633 rcu_read_lock();
634 list_for_each_entry_from_rcu(info, &context->records_list, list) {
635 if (before(seq, info->end_seq)) {
636 if (!context->retransmit_hint ||
637 after(info->end_seq,
638 context->retransmit_hint->end_seq)) {
639 context->hint_record_sn = record_sn;
640 context->retransmit_hint = info;
641 }
642 *p_record_sn = record_sn;
643 goto exit_rcu_unlock;
644 }
645 record_sn++;
646 }
647 info = NULL;
648
649 exit_rcu_unlock:
650 rcu_read_unlock();
651 return info;
652 }
653 EXPORT_SYMBOL(tls_get_record);
654
tls_device_push_pending_record(struct sock * sk,int flags)655 static int tls_device_push_pending_record(struct sock *sk, int flags)
656 {
657 struct iov_iter msg_iter;
658
659 iov_iter_kvec(&msg_iter, WRITE, NULL, 0, 0);
660 return tls_push_data(sk, &msg_iter, 0, flags, TLS_RECORD_TYPE_DATA);
661 }
662
tls_device_write_space(struct sock * sk,struct tls_context * ctx)663 void tls_device_write_space(struct sock *sk, struct tls_context *ctx)
664 {
665 if (tls_is_partially_sent_record(ctx)) {
666 gfp_t sk_allocation = sk->sk_allocation;
667
668 WARN_ON_ONCE(sk->sk_write_pending);
669
670 sk->sk_allocation = GFP_ATOMIC;
671 tls_push_partial_record(sk, ctx,
672 MSG_DONTWAIT | MSG_NOSIGNAL |
673 MSG_SENDPAGE_DECRYPTED);
674 sk->sk_allocation = sk_allocation;
675 }
676 }
677
tls_device_resync_rx(struct tls_context * tls_ctx,struct sock * sk,u32 seq,u8 * rcd_sn)678 static void tls_device_resync_rx(struct tls_context *tls_ctx,
679 struct sock *sk, u32 seq, u8 *rcd_sn)
680 {
681 struct tls_offload_context_rx *rx_ctx = tls_offload_ctx_rx(tls_ctx);
682 struct net_device *netdev;
683
684 trace_tls_device_rx_resync_send(sk, seq, rcd_sn, rx_ctx->resync_type);
685 rcu_read_lock();
686 netdev = READ_ONCE(tls_ctx->netdev);
687 if (netdev)
688 netdev->tlsdev_ops->tls_dev_resync(netdev, sk, seq, rcd_sn,
689 TLS_OFFLOAD_CTX_DIR_RX);
690 rcu_read_unlock();
691 TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSRXDEVICERESYNC);
692 }
693
694 static bool
tls_device_rx_resync_async(struct tls_offload_resync_async * resync_async,s64 resync_req,u32 * seq,u16 * rcd_delta)695 tls_device_rx_resync_async(struct tls_offload_resync_async *resync_async,
696 s64 resync_req, u32 *seq, u16 *rcd_delta)
697 {
698 u32 is_async = resync_req & RESYNC_REQ_ASYNC;
699 u32 req_seq = resync_req >> 32;
700 u32 req_end = req_seq + ((resync_req >> 16) & 0xffff);
701 u16 i;
702
703 *rcd_delta = 0;
704
705 if (is_async) {
706 /* shouldn't get to wraparound:
707 * too long in async stage, something bad happened
708 */
709 if (WARN_ON_ONCE(resync_async->rcd_delta == USHRT_MAX))
710 return false;
711
712 /* asynchronous stage: log all headers seq such that
713 * req_seq <= seq <= end_seq, and wait for real resync request
714 */
715 if (before(*seq, req_seq))
716 return false;
717 if (!after(*seq, req_end) &&
718 resync_async->loglen < TLS_DEVICE_RESYNC_ASYNC_LOGMAX)
719 resync_async->log[resync_async->loglen++] = *seq;
720
721 resync_async->rcd_delta++;
722
723 return false;
724 }
725
726 /* synchronous stage: check against the logged entries and
727 * proceed to check the next entries if no match was found
728 */
729 for (i = 0; i < resync_async->loglen; i++)
730 if (req_seq == resync_async->log[i] &&
731 atomic64_try_cmpxchg(&resync_async->req, &resync_req, 0)) {
732 *rcd_delta = resync_async->rcd_delta - i;
733 *seq = req_seq;
734 resync_async->loglen = 0;
735 resync_async->rcd_delta = 0;
736 return true;
737 }
738
739 resync_async->loglen = 0;
740 resync_async->rcd_delta = 0;
741
742 if (req_seq == *seq &&
743 atomic64_try_cmpxchg(&resync_async->req,
744 &resync_req, 0))
745 return true;
746
747 return false;
748 }
749
tls_device_rx_resync_new_rec(struct sock * sk,u32 rcd_len,u32 seq)750 void tls_device_rx_resync_new_rec(struct sock *sk, u32 rcd_len, u32 seq)
751 {
752 struct tls_context *tls_ctx = tls_get_ctx(sk);
753 struct tls_offload_context_rx *rx_ctx;
754 u8 rcd_sn[TLS_MAX_REC_SEQ_SIZE];
755 u32 sock_data, is_req_pending;
756 struct tls_prot_info *prot;
757 s64 resync_req;
758 u16 rcd_delta;
759 u32 req_seq;
760
761 if (tls_ctx->rx_conf != TLS_HW)
762 return;
763 if (unlikely(test_bit(TLS_RX_DEV_DEGRADED, &tls_ctx->flags)))
764 return;
765
766 prot = &tls_ctx->prot_info;
767 rx_ctx = tls_offload_ctx_rx(tls_ctx);
768 memcpy(rcd_sn, tls_ctx->rx.rec_seq, prot->rec_seq_size);
769
770 switch (rx_ctx->resync_type) {
771 case TLS_OFFLOAD_SYNC_TYPE_DRIVER_REQ:
772 resync_req = atomic64_read(&rx_ctx->resync_req);
773 req_seq = resync_req >> 32;
774 seq += TLS_HEADER_SIZE - 1;
775 is_req_pending = resync_req;
776
777 if (likely(!is_req_pending) || req_seq != seq ||
778 !atomic64_try_cmpxchg(&rx_ctx->resync_req, &resync_req, 0))
779 return;
780 break;
781 case TLS_OFFLOAD_SYNC_TYPE_CORE_NEXT_HINT:
782 if (likely(!rx_ctx->resync_nh_do_now))
783 return;
784
785 /* head of next rec is already in, note that the sock_inq will
786 * include the currently parsed message when called from parser
787 */
788 sock_data = tcp_inq(sk);
789 if (sock_data > rcd_len) {
790 trace_tls_device_rx_resync_nh_delay(sk, sock_data,
791 rcd_len);
792 return;
793 }
794
795 rx_ctx->resync_nh_do_now = 0;
796 seq += rcd_len;
797 tls_bigint_increment(rcd_sn, prot->rec_seq_size);
798 break;
799 case TLS_OFFLOAD_SYNC_TYPE_DRIVER_REQ_ASYNC:
800 resync_req = atomic64_read(&rx_ctx->resync_async->req);
801 is_req_pending = resync_req;
802 if (likely(!is_req_pending))
803 return;
804
805 if (!tls_device_rx_resync_async(rx_ctx->resync_async,
806 resync_req, &seq, &rcd_delta))
807 return;
808 tls_bigint_subtract(rcd_sn, rcd_delta);
809 break;
810 }
811
812 tls_device_resync_rx(tls_ctx, sk, seq, rcd_sn);
813 }
814
tls_device_core_ctrl_rx_resync(struct tls_context * tls_ctx,struct tls_offload_context_rx * ctx,struct sock * sk,struct sk_buff * skb)815 static void tls_device_core_ctrl_rx_resync(struct tls_context *tls_ctx,
816 struct tls_offload_context_rx *ctx,
817 struct sock *sk, struct sk_buff *skb)
818 {
819 struct strp_msg *rxm;
820
821 /* device will request resyncs by itself based on stream scan */
822 if (ctx->resync_type != TLS_OFFLOAD_SYNC_TYPE_CORE_NEXT_HINT)
823 return;
824 /* already scheduled */
825 if (ctx->resync_nh_do_now)
826 return;
827 /* seen decrypted fragments since last fully-failed record */
828 if (ctx->resync_nh_reset) {
829 ctx->resync_nh_reset = 0;
830 ctx->resync_nh.decrypted_failed = 1;
831 ctx->resync_nh.decrypted_tgt = TLS_DEVICE_RESYNC_NH_START_IVAL;
832 return;
833 }
834
835 if (++ctx->resync_nh.decrypted_failed <= ctx->resync_nh.decrypted_tgt)
836 return;
837
838 /* doing resync, bump the next target in case it fails */
839 if (ctx->resync_nh.decrypted_tgt < TLS_DEVICE_RESYNC_NH_MAX_IVAL)
840 ctx->resync_nh.decrypted_tgt *= 2;
841 else
842 ctx->resync_nh.decrypted_tgt += TLS_DEVICE_RESYNC_NH_MAX_IVAL;
843
844 rxm = strp_msg(skb);
845
846 /* head of next rec is already in, parser will sync for us */
847 if (tcp_inq(sk) > rxm->full_len) {
848 trace_tls_device_rx_resync_nh_schedule(sk);
849 ctx->resync_nh_do_now = 1;
850 } else {
851 struct tls_prot_info *prot = &tls_ctx->prot_info;
852 u8 rcd_sn[TLS_MAX_REC_SEQ_SIZE];
853
854 memcpy(rcd_sn, tls_ctx->rx.rec_seq, prot->rec_seq_size);
855 tls_bigint_increment(rcd_sn, prot->rec_seq_size);
856
857 tls_device_resync_rx(tls_ctx, sk, tcp_sk(sk)->copied_seq,
858 rcd_sn);
859 }
860 }
861
tls_device_reencrypt(struct sock * sk,struct sk_buff * skb)862 static int tls_device_reencrypt(struct sock *sk, struct sk_buff *skb)
863 {
864 struct strp_msg *rxm = strp_msg(skb);
865 int err = 0, offset = rxm->offset, copy, nsg, data_len, pos;
866 struct sk_buff *skb_iter, *unused;
867 struct scatterlist sg[1];
868 char *orig_buf, *buf;
869
870 orig_buf = kmalloc(rxm->full_len + TLS_HEADER_SIZE +
871 TLS_CIPHER_AES_GCM_128_IV_SIZE, sk->sk_allocation);
872 if (!orig_buf)
873 return -ENOMEM;
874 buf = orig_buf;
875
876 nsg = skb_cow_data(skb, 0, &unused);
877 if (unlikely(nsg < 0)) {
878 err = nsg;
879 goto free_buf;
880 }
881
882 sg_init_table(sg, 1);
883 sg_set_buf(&sg[0], buf,
884 rxm->full_len + TLS_HEADER_SIZE +
885 TLS_CIPHER_AES_GCM_128_IV_SIZE);
886 err = skb_copy_bits(skb, offset, buf,
887 TLS_HEADER_SIZE + TLS_CIPHER_AES_GCM_128_IV_SIZE);
888 if (err)
889 goto free_buf;
890
891 /* We are interested only in the decrypted data not the auth */
892 err = decrypt_skb(sk, skb, sg);
893 if (err != -EBADMSG)
894 goto free_buf;
895 else
896 err = 0;
897
898 data_len = rxm->full_len - TLS_CIPHER_AES_GCM_128_TAG_SIZE;
899
900 if (skb_pagelen(skb) > offset) {
901 copy = min_t(int, skb_pagelen(skb) - offset, data_len);
902
903 if (skb->decrypted) {
904 err = skb_store_bits(skb, offset, buf, copy);
905 if (err)
906 goto free_buf;
907 }
908
909 offset += copy;
910 buf += copy;
911 }
912
913 pos = skb_pagelen(skb);
914 skb_walk_frags(skb, skb_iter) {
915 int frag_pos;
916
917 /* Practically all frags must belong to msg if reencrypt
918 * is needed with current strparser and coalescing logic,
919 * but strparser may "get optimized", so let's be safe.
920 */
921 if (pos + skb_iter->len <= offset)
922 goto done_with_frag;
923 if (pos >= data_len + rxm->offset)
924 break;
925
926 frag_pos = offset - pos;
927 copy = min_t(int, skb_iter->len - frag_pos,
928 data_len + rxm->offset - offset);
929
930 if (skb_iter->decrypted) {
931 err = skb_store_bits(skb_iter, frag_pos, buf, copy);
932 if (err)
933 goto free_buf;
934 }
935
936 offset += copy;
937 buf += copy;
938 done_with_frag:
939 pos += skb_iter->len;
940 }
941
942 free_buf:
943 kfree(orig_buf);
944 return err;
945 }
946
tls_device_decrypted(struct sock * sk,struct tls_context * tls_ctx,struct sk_buff * skb,struct strp_msg * rxm)947 int tls_device_decrypted(struct sock *sk, struct tls_context *tls_ctx,
948 struct sk_buff *skb, struct strp_msg *rxm)
949 {
950 struct tls_offload_context_rx *ctx = tls_offload_ctx_rx(tls_ctx);
951 int is_decrypted = skb->decrypted;
952 int is_encrypted = !is_decrypted;
953 struct sk_buff *skb_iter;
954
955 /* Check if all the data is decrypted already */
956 skb_walk_frags(skb, skb_iter) {
957 is_decrypted &= skb_iter->decrypted;
958 is_encrypted &= !skb_iter->decrypted;
959 }
960
961 trace_tls_device_decrypted(sk, tcp_sk(sk)->copied_seq - rxm->full_len,
962 tls_ctx->rx.rec_seq, rxm->full_len,
963 is_encrypted, is_decrypted);
964
965 ctx->sw.decrypted |= is_decrypted;
966
967 if (unlikely(test_bit(TLS_RX_DEV_DEGRADED, &tls_ctx->flags))) {
968 if (likely(is_encrypted || is_decrypted))
969 return 0;
970
971 /* After tls_device_down disables the offload, the next SKB will
972 * likely have initial fragments decrypted, and final ones not
973 * decrypted. We need to reencrypt that single SKB.
974 */
975 return tls_device_reencrypt(sk, skb);
976 }
977
978 /* Return immediately if the record is either entirely plaintext or
979 * entirely ciphertext. Otherwise handle reencrypt partially decrypted
980 * record.
981 */
982 if (is_decrypted) {
983 ctx->resync_nh_reset = 1;
984 return 0;
985 }
986 if (is_encrypted) {
987 tls_device_core_ctrl_rx_resync(tls_ctx, ctx, sk, skb);
988 return 0;
989 }
990
991 ctx->resync_nh_reset = 1;
992 return tls_device_reencrypt(sk, skb);
993 }
994
tls_device_attach(struct tls_context * ctx,struct sock * sk,struct net_device * netdev)995 static void tls_device_attach(struct tls_context *ctx, struct sock *sk,
996 struct net_device *netdev)
997 {
998 if (sk->sk_destruct != tls_device_sk_destruct) {
999 refcount_set(&ctx->refcount, 1);
1000 dev_hold(netdev);
1001 ctx->netdev = netdev;
1002 spin_lock_irq(&tls_device_lock);
1003 list_add_tail(&ctx->list, &tls_device_list);
1004 spin_unlock_irq(&tls_device_lock);
1005
1006 ctx->sk_destruct = sk->sk_destruct;
1007 smp_store_release(&sk->sk_destruct, tls_device_sk_destruct);
1008 }
1009 }
1010
tls_set_device_offload(struct sock * sk,struct tls_context * ctx)1011 int tls_set_device_offload(struct sock *sk, struct tls_context *ctx)
1012 {
1013 u16 nonce_size, tag_size, iv_size, rec_seq_size;
1014 struct tls_context *tls_ctx = tls_get_ctx(sk);
1015 struct tls_prot_info *prot = &tls_ctx->prot_info;
1016 struct tls_record_info *start_marker_record;
1017 struct tls_offload_context_tx *offload_ctx;
1018 struct tls_crypto_info *crypto_info;
1019 struct net_device *netdev;
1020 char *iv, *rec_seq;
1021 struct sk_buff *skb;
1022 __be64 rcd_sn;
1023 int rc;
1024
1025 if (!ctx)
1026 return -EINVAL;
1027
1028 if (ctx->priv_ctx_tx)
1029 return -EEXIST;
1030
1031 start_marker_record = kmalloc(sizeof(*start_marker_record), GFP_KERNEL);
1032 if (!start_marker_record)
1033 return -ENOMEM;
1034
1035 offload_ctx = kzalloc(TLS_OFFLOAD_CONTEXT_SIZE_TX, GFP_KERNEL);
1036 if (!offload_ctx) {
1037 rc = -ENOMEM;
1038 goto free_marker_record;
1039 }
1040
1041 crypto_info = &ctx->crypto_send.info;
1042 if (crypto_info->version != TLS_1_2_VERSION) {
1043 rc = -EOPNOTSUPP;
1044 goto free_offload_ctx;
1045 }
1046
1047 switch (crypto_info->cipher_type) {
1048 case TLS_CIPHER_AES_GCM_128:
1049 nonce_size = TLS_CIPHER_AES_GCM_128_IV_SIZE;
1050 tag_size = TLS_CIPHER_AES_GCM_128_TAG_SIZE;
1051 iv_size = TLS_CIPHER_AES_GCM_128_IV_SIZE;
1052 iv = ((struct tls12_crypto_info_aes_gcm_128 *)crypto_info)->iv;
1053 rec_seq_size = TLS_CIPHER_AES_GCM_128_REC_SEQ_SIZE;
1054 rec_seq =
1055 ((struct tls12_crypto_info_aes_gcm_128 *)crypto_info)->rec_seq;
1056 break;
1057 default:
1058 rc = -EINVAL;
1059 goto free_offload_ctx;
1060 }
1061
1062 /* Sanity-check the rec_seq_size for stack allocations */
1063 if (rec_seq_size > TLS_MAX_REC_SEQ_SIZE) {
1064 rc = -EINVAL;
1065 goto free_offload_ctx;
1066 }
1067
1068 prot->version = crypto_info->version;
1069 prot->cipher_type = crypto_info->cipher_type;
1070 prot->prepend_size = TLS_HEADER_SIZE + nonce_size;
1071 prot->tag_size = tag_size;
1072 prot->overhead_size = prot->prepend_size + prot->tag_size;
1073 prot->iv_size = iv_size;
1074 ctx->tx.iv = kmalloc(iv_size + TLS_CIPHER_AES_GCM_128_SALT_SIZE,
1075 GFP_KERNEL);
1076 if (!ctx->tx.iv) {
1077 rc = -ENOMEM;
1078 goto free_offload_ctx;
1079 }
1080
1081 memcpy(ctx->tx.iv + TLS_CIPHER_AES_GCM_128_SALT_SIZE, iv, iv_size);
1082
1083 prot->rec_seq_size = rec_seq_size;
1084 ctx->tx.rec_seq = kmemdup(rec_seq, rec_seq_size, GFP_KERNEL);
1085 if (!ctx->tx.rec_seq) {
1086 rc = -ENOMEM;
1087 goto free_iv;
1088 }
1089
1090 rc = tls_sw_fallback_init(sk, offload_ctx, crypto_info);
1091 if (rc)
1092 goto free_rec_seq;
1093
1094 /* start at rec_seq - 1 to account for the start marker record */
1095 memcpy(&rcd_sn, ctx->tx.rec_seq, sizeof(rcd_sn));
1096 offload_ctx->unacked_record_sn = be64_to_cpu(rcd_sn) - 1;
1097
1098 start_marker_record->end_seq = tcp_sk(sk)->write_seq;
1099 start_marker_record->len = 0;
1100 start_marker_record->num_frags = 0;
1101
1102 INIT_LIST_HEAD(&offload_ctx->records_list);
1103 list_add_tail(&start_marker_record->list, &offload_ctx->records_list);
1104 spin_lock_init(&offload_ctx->lock);
1105 sg_init_table(offload_ctx->sg_tx_data,
1106 ARRAY_SIZE(offload_ctx->sg_tx_data));
1107
1108 clean_acked_data_enable(inet_csk(sk), &tls_icsk_clean_acked);
1109 ctx->push_pending_record = tls_device_push_pending_record;
1110
1111 /* TLS offload is greatly simplified if we don't send
1112 * SKBs where only part of the payload needs to be encrypted.
1113 * So mark the last skb in the write queue as end of record.
1114 */
1115 skb = tcp_write_queue_tail(sk);
1116 if (skb)
1117 TCP_SKB_CB(skb)->eor = 1;
1118
1119 netdev = get_netdev_for_sock(sk);
1120 if (!netdev) {
1121 pr_err_ratelimited("%s: netdev not found\n", __func__);
1122 rc = -EINVAL;
1123 goto disable_cad;
1124 }
1125
1126 if (!(netdev->features & NETIF_F_HW_TLS_TX)) {
1127 rc = -EOPNOTSUPP;
1128 goto release_netdev;
1129 }
1130
1131 /* Avoid offloading if the device is down
1132 * We don't want to offload new flows after
1133 * the NETDEV_DOWN event
1134 *
1135 * device_offload_lock is taken in tls_devices's NETDEV_DOWN
1136 * handler thus protecting from the device going down before
1137 * ctx was added to tls_device_list.
1138 */
1139 down_read(&device_offload_lock);
1140 if (!(netdev->flags & IFF_UP)) {
1141 rc = -EINVAL;
1142 goto release_lock;
1143 }
1144
1145 ctx->priv_ctx_tx = offload_ctx;
1146 rc = netdev->tlsdev_ops->tls_dev_add(netdev, sk, TLS_OFFLOAD_CTX_DIR_TX,
1147 &ctx->crypto_send.info,
1148 tcp_sk(sk)->write_seq);
1149 trace_tls_device_offload_set(sk, TLS_OFFLOAD_CTX_DIR_TX,
1150 tcp_sk(sk)->write_seq, rec_seq, rc);
1151 if (rc)
1152 goto release_lock;
1153
1154 tls_device_attach(ctx, sk, netdev);
1155 up_read(&device_offload_lock);
1156
1157 /* following this assignment tls_is_sk_tx_device_offloaded
1158 * will return true and the context might be accessed
1159 * by the netdev's xmit function.
1160 */
1161 smp_store_release(&sk->sk_validate_xmit_skb, tls_validate_xmit_skb);
1162 dev_put(netdev);
1163
1164 return 0;
1165
1166 release_lock:
1167 up_read(&device_offload_lock);
1168 release_netdev:
1169 dev_put(netdev);
1170 disable_cad:
1171 clean_acked_data_disable(inet_csk(sk));
1172 crypto_free_aead(offload_ctx->aead_send);
1173 free_rec_seq:
1174 kfree(ctx->tx.rec_seq);
1175 free_iv:
1176 kfree(ctx->tx.iv);
1177 free_offload_ctx:
1178 kfree(offload_ctx);
1179 ctx->priv_ctx_tx = NULL;
1180 free_marker_record:
1181 kfree(start_marker_record);
1182 return rc;
1183 }
1184
tls_set_device_offload_rx(struct sock * sk,struct tls_context * ctx)1185 int tls_set_device_offload_rx(struct sock *sk, struct tls_context *ctx)
1186 {
1187 struct tls12_crypto_info_aes_gcm_128 *info;
1188 struct tls_offload_context_rx *context;
1189 struct net_device *netdev;
1190 int rc = 0;
1191
1192 if (ctx->crypto_recv.info.version != TLS_1_2_VERSION)
1193 return -EOPNOTSUPP;
1194
1195 netdev = get_netdev_for_sock(sk);
1196 if (!netdev) {
1197 pr_err_ratelimited("%s: netdev not found\n", __func__);
1198 return -EINVAL;
1199 }
1200
1201 if (!(netdev->features & NETIF_F_HW_TLS_RX)) {
1202 rc = -EOPNOTSUPP;
1203 goto release_netdev;
1204 }
1205
1206 /* Avoid offloading if the device is down
1207 * We don't want to offload new flows after
1208 * the NETDEV_DOWN event
1209 *
1210 * device_offload_lock is taken in tls_devices's NETDEV_DOWN
1211 * handler thus protecting from the device going down before
1212 * ctx was added to tls_device_list.
1213 */
1214 down_read(&device_offload_lock);
1215 if (!(netdev->flags & IFF_UP)) {
1216 rc = -EINVAL;
1217 goto release_lock;
1218 }
1219
1220 context = kzalloc(TLS_OFFLOAD_CONTEXT_SIZE_RX, GFP_KERNEL);
1221 if (!context) {
1222 rc = -ENOMEM;
1223 goto release_lock;
1224 }
1225 context->resync_nh_reset = 1;
1226
1227 ctx->priv_ctx_rx = context;
1228 rc = tls_set_sw_offload(sk, ctx, 0);
1229 if (rc)
1230 goto release_ctx;
1231
1232 rc = netdev->tlsdev_ops->tls_dev_add(netdev, sk, TLS_OFFLOAD_CTX_DIR_RX,
1233 &ctx->crypto_recv.info,
1234 tcp_sk(sk)->copied_seq);
1235 info = (void *)&ctx->crypto_recv.info;
1236 trace_tls_device_offload_set(sk, TLS_OFFLOAD_CTX_DIR_RX,
1237 tcp_sk(sk)->copied_seq, info->rec_seq, rc);
1238 if (rc)
1239 goto free_sw_resources;
1240
1241 tls_device_attach(ctx, sk, netdev);
1242 up_read(&device_offload_lock);
1243
1244 dev_put(netdev);
1245
1246 return 0;
1247
1248 free_sw_resources:
1249 up_read(&device_offload_lock);
1250 tls_sw_free_resources_rx(sk);
1251 down_read(&device_offload_lock);
1252 release_ctx:
1253 ctx->priv_ctx_rx = NULL;
1254 release_lock:
1255 up_read(&device_offload_lock);
1256 release_netdev:
1257 dev_put(netdev);
1258 return rc;
1259 }
1260
tls_device_offload_cleanup_rx(struct sock * sk)1261 void tls_device_offload_cleanup_rx(struct sock *sk)
1262 {
1263 struct tls_context *tls_ctx = tls_get_ctx(sk);
1264 struct net_device *netdev;
1265
1266 down_read(&device_offload_lock);
1267 netdev = tls_ctx->netdev;
1268 if (!netdev)
1269 goto out;
1270
1271 netdev->tlsdev_ops->tls_dev_del(netdev, tls_ctx,
1272 TLS_OFFLOAD_CTX_DIR_RX);
1273
1274 if (tls_ctx->tx_conf != TLS_HW) {
1275 dev_put(netdev);
1276 tls_ctx->netdev = NULL;
1277 } else {
1278 set_bit(TLS_RX_DEV_CLOSED, &tls_ctx->flags);
1279 }
1280 out:
1281 up_read(&device_offload_lock);
1282 tls_sw_release_resources_rx(sk);
1283 }
1284
tls_device_down(struct net_device * netdev)1285 static int tls_device_down(struct net_device *netdev)
1286 {
1287 struct tls_context *ctx, *tmp;
1288 unsigned long flags;
1289 LIST_HEAD(list);
1290
1291 /* Request a write lock to block new offload attempts */
1292 down_write(&device_offload_lock);
1293
1294 spin_lock_irqsave(&tls_device_lock, flags);
1295 list_for_each_entry_safe(ctx, tmp, &tls_device_list, list) {
1296 if (ctx->netdev != netdev ||
1297 !refcount_inc_not_zero(&ctx->refcount))
1298 continue;
1299
1300 list_move(&ctx->list, &list);
1301 }
1302 spin_unlock_irqrestore(&tls_device_lock, flags);
1303
1304 list_for_each_entry_safe(ctx, tmp, &list, list) {
1305 /* Stop offloaded TX and switch to the fallback.
1306 * tls_is_sk_tx_device_offloaded will return false.
1307 */
1308 WRITE_ONCE(ctx->sk->sk_validate_xmit_skb, tls_validate_xmit_skb_sw);
1309
1310 /* Stop the RX and TX resync.
1311 * tls_dev_resync must not be called after tls_dev_del.
1312 */
1313 WRITE_ONCE(ctx->netdev, NULL);
1314
1315 /* Start skipping the RX resync logic completely. */
1316 set_bit(TLS_RX_DEV_DEGRADED, &ctx->flags);
1317
1318 /* Sync with inflight packets. After this point:
1319 * TX: no non-encrypted packets will be passed to the driver.
1320 * RX: resync requests from the driver will be ignored.
1321 */
1322 synchronize_net();
1323
1324 /* Release the offload context on the driver side. */
1325 if (ctx->tx_conf == TLS_HW)
1326 netdev->tlsdev_ops->tls_dev_del(netdev, ctx,
1327 TLS_OFFLOAD_CTX_DIR_TX);
1328 if (ctx->rx_conf == TLS_HW &&
1329 !test_bit(TLS_RX_DEV_CLOSED, &ctx->flags))
1330 netdev->tlsdev_ops->tls_dev_del(netdev, ctx,
1331 TLS_OFFLOAD_CTX_DIR_RX);
1332
1333 dev_put(netdev);
1334
1335 /* Move the context to a separate list for two reasons:
1336 * 1. When the context is deallocated, list_del is called.
1337 * 2. It's no longer an offloaded context, so we don't want to
1338 * run offload-specific code on this context.
1339 */
1340 spin_lock_irqsave(&tls_device_lock, flags);
1341 list_move_tail(&ctx->list, &tls_device_down_list);
1342 spin_unlock_irqrestore(&tls_device_lock, flags);
1343
1344 /* Device contexts for RX and TX will be freed in on sk_destruct
1345 * by tls_device_free_ctx. rx_conf and tx_conf stay in TLS_HW.
1346 */
1347 }
1348
1349 up_write(&device_offload_lock);
1350
1351 flush_work(&tls_device_gc_work);
1352
1353 return NOTIFY_DONE;
1354 }
1355
tls_dev_event(struct notifier_block * this,unsigned long event,void * ptr)1356 static int tls_dev_event(struct notifier_block *this, unsigned long event,
1357 void *ptr)
1358 {
1359 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
1360
1361 if (!dev->tlsdev_ops &&
1362 !(dev->features & (NETIF_F_HW_TLS_RX | NETIF_F_HW_TLS_TX)))
1363 return NOTIFY_DONE;
1364
1365 switch (event) {
1366 case NETDEV_REGISTER:
1367 case NETDEV_FEAT_CHANGE:
1368 if ((dev->features & NETIF_F_HW_TLS_RX) &&
1369 !dev->tlsdev_ops->tls_dev_resync)
1370 return NOTIFY_BAD;
1371
1372 if (dev->tlsdev_ops &&
1373 dev->tlsdev_ops->tls_dev_add &&
1374 dev->tlsdev_ops->tls_dev_del)
1375 return NOTIFY_DONE;
1376 else
1377 return NOTIFY_BAD;
1378 case NETDEV_DOWN:
1379 return tls_device_down(dev);
1380 }
1381 return NOTIFY_DONE;
1382 }
1383
1384 static struct notifier_block tls_dev_notifier = {
1385 .notifier_call = tls_dev_event,
1386 };
1387
tls_device_init(void)1388 void __init tls_device_init(void)
1389 {
1390 register_netdevice_notifier(&tls_dev_notifier);
1391 }
1392
tls_device_cleanup(void)1393 void __exit tls_device_cleanup(void)
1394 {
1395 unregister_netdevice_notifier(&tls_dev_notifier);
1396 flush_work(&tls_device_gc_work);
1397 clean_acked_data_flush();
1398 }
1399