Loading...
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * af_alg: User-space algorithm interface
4 *
5 * This file provides the user-space API for algorithms.
6 *
7 * Copyright (c) 2010 Herbert Xu <herbert@gondor.apana.org.au>
8 */
9
10#include <linux/atomic.h>
11#include <crypto/if_alg.h>
12#include <linux/crypto.h>
13#include <linux/init.h>
14#include <linux/kernel.h>
15#include <linux/list.h>
16#include <linux/module.h>
17#include <linux/net.h>
18#include <linux/rwsem.h>
19#include <linux/sched.h>
20#include <linux/sched/signal.h>
21#include <linux/security.h>
22
23struct alg_type_list {
24 const struct af_alg_type *type;
25 struct list_head list;
26};
27
28static atomic_long_t alg_memory_allocated;
29
30static struct proto alg_proto = {
31 .name = "ALG",
32 .owner = THIS_MODULE,
33 .memory_allocated = &alg_memory_allocated,
34 .obj_size = sizeof(struct alg_sock),
35};
36
37static LIST_HEAD(alg_types);
38static DECLARE_RWSEM(alg_types_sem);
39
40static const struct af_alg_type *alg_get_type(const char *name)
41{
42 const struct af_alg_type *type = ERR_PTR(-ENOENT);
43 struct alg_type_list *node;
44
45 down_read(&alg_types_sem);
46 list_for_each_entry(node, &alg_types, list) {
47 if (strcmp(node->type->name, name))
48 continue;
49
50 if (try_module_get(node->type->owner))
51 type = node->type;
52 break;
53 }
54 up_read(&alg_types_sem);
55
56 return type;
57}
58
59int af_alg_register_type(const struct af_alg_type *type)
60{
61 struct alg_type_list *node;
62 int err = -EEXIST;
63
64 down_write(&alg_types_sem);
65 list_for_each_entry(node, &alg_types, list) {
66 if (!strcmp(node->type->name, type->name))
67 goto unlock;
68 }
69
70 node = kmalloc(sizeof(*node), GFP_KERNEL);
71 err = -ENOMEM;
72 if (!node)
73 goto unlock;
74
75 type->ops->owner = THIS_MODULE;
76 if (type->ops_nokey)
77 type->ops_nokey->owner = THIS_MODULE;
78 node->type = type;
79 list_add(&node->list, &alg_types);
80 err = 0;
81
82unlock:
83 up_write(&alg_types_sem);
84
85 return err;
86}
87EXPORT_SYMBOL_GPL(af_alg_register_type);
88
89int af_alg_unregister_type(const struct af_alg_type *type)
90{
91 struct alg_type_list *node;
92 int err = -ENOENT;
93
94 down_write(&alg_types_sem);
95 list_for_each_entry(node, &alg_types, list) {
96 if (strcmp(node->type->name, type->name))
97 continue;
98
99 list_del(&node->list);
100 kfree(node);
101 err = 0;
102 break;
103 }
104 up_write(&alg_types_sem);
105
106 return err;
107}
108EXPORT_SYMBOL_GPL(af_alg_unregister_type);
109
110static void alg_do_release(const struct af_alg_type *type, void *private)
111{
112 if (!type)
113 return;
114
115 type->release(private);
116 module_put(type->owner);
117}
118
119int af_alg_release(struct socket *sock)
120{
121 if (sock->sk) {
122 sock_put(sock->sk);
123 sock->sk = NULL;
124 }
125 return 0;
126}
127EXPORT_SYMBOL_GPL(af_alg_release);
128
129void af_alg_release_parent(struct sock *sk)
130{
131 struct alg_sock *ask = alg_sk(sk);
132 unsigned int nokey = atomic_read(&ask->nokey_refcnt);
133
134 sk = ask->parent;
135 ask = alg_sk(sk);
136
137 if (nokey)
138 atomic_dec(&ask->nokey_refcnt);
139
140 if (atomic_dec_and_test(&ask->refcnt))
141 sock_put(sk);
142}
143EXPORT_SYMBOL_GPL(af_alg_release_parent);
144
145static int alg_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
146{
147 const u32 allowed = CRYPTO_ALG_KERN_DRIVER_ONLY;
148 struct sock *sk = sock->sk;
149 struct alg_sock *ask = alg_sk(sk);
150 struct sockaddr_alg *sa = (void *)uaddr;
151 const struct af_alg_type *type;
152 void *private;
153 int err;
154
155 if (sock->state == SS_CONNECTED)
156 return -EINVAL;
157
158 if (addr_len < sizeof(*sa))
159 return -EINVAL;
160
161 /* If caller uses non-allowed flag, return error. */
162 if ((sa->salg_feat & ~allowed) || (sa->salg_mask & ~allowed))
163 return -EINVAL;
164
165 sa->salg_type[sizeof(sa->salg_type) - 1] = 0;
166 sa->salg_name[sizeof(sa->salg_name) + addr_len - sizeof(*sa) - 1] = 0;
167
168 type = alg_get_type(sa->salg_type);
169 if (PTR_ERR(type) == -ENOENT) {
170 request_module("algif-%s", sa->salg_type);
171 type = alg_get_type(sa->salg_type);
172 }
173
174 if (IS_ERR(type))
175 return PTR_ERR(type);
176
177 private = type->bind(sa->salg_name, sa->salg_feat, sa->salg_mask);
178 if (IS_ERR(private)) {
179 module_put(type->owner);
180 return PTR_ERR(private);
181 }
182
183 err = -EBUSY;
184 lock_sock(sk);
185 if (atomic_read(&ask->refcnt))
186 goto unlock;
187
188 swap(ask->type, type);
189 swap(ask->private, private);
190
191 err = 0;
192
193unlock:
194 release_sock(sk);
195
196 alg_do_release(type, private);
197
198 return err;
199}
200
201static int alg_setkey(struct sock *sk, sockptr_t ukey, unsigned int keylen)
202{
203 struct alg_sock *ask = alg_sk(sk);
204 const struct af_alg_type *type = ask->type;
205 u8 *key;
206 int err;
207
208 key = sock_kmalloc(sk, keylen, GFP_KERNEL);
209 if (!key)
210 return -ENOMEM;
211
212 err = -EFAULT;
213 if (copy_from_sockptr(key, ukey, keylen))
214 goto out;
215
216 err = type->setkey(ask->private, key, keylen);
217
218out:
219 sock_kzfree_s(sk, key, keylen);
220
221 return err;
222}
223
224static int alg_setsockopt(struct socket *sock, int level, int optname,
225 sockptr_t optval, unsigned int optlen)
226{
227 struct sock *sk = sock->sk;
228 struct alg_sock *ask = alg_sk(sk);
229 const struct af_alg_type *type;
230 int err = -EBUSY;
231
232 lock_sock(sk);
233 if (atomic_read(&ask->refcnt) != atomic_read(&ask->nokey_refcnt))
234 goto unlock;
235
236 type = ask->type;
237
238 err = -ENOPROTOOPT;
239 if (level != SOL_ALG || !type)
240 goto unlock;
241
242 switch (optname) {
243 case ALG_SET_KEY:
244 if (sock->state == SS_CONNECTED)
245 goto unlock;
246 if (!type->setkey)
247 goto unlock;
248
249 err = alg_setkey(sk, optval, optlen);
250 break;
251 case ALG_SET_AEAD_AUTHSIZE:
252 if (sock->state == SS_CONNECTED)
253 goto unlock;
254 if (!type->setauthsize)
255 goto unlock;
256 err = type->setauthsize(ask->private, optlen);
257 }
258
259unlock:
260 release_sock(sk);
261
262 return err;
263}
264
265int af_alg_accept(struct sock *sk, struct socket *newsock, bool kern)
266{
267 struct alg_sock *ask = alg_sk(sk);
268 const struct af_alg_type *type;
269 struct sock *sk2;
270 unsigned int nokey;
271 int err;
272
273 lock_sock(sk);
274 type = ask->type;
275
276 err = -EINVAL;
277 if (!type)
278 goto unlock;
279
280 sk2 = sk_alloc(sock_net(sk), PF_ALG, GFP_KERNEL, &alg_proto, kern);
281 err = -ENOMEM;
282 if (!sk2)
283 goto unlock;
284
285 sock_init_data(newsock, sk2);
286 security_sock_graft(sk2, newsock);
287 security_sk_clone(sk, sk2);
288
289 err = type->accept(ask->private, sk2);
290
291 nokey = err == -ENOKEY;
292 if (nokey && type->accept_nokey)
293 err = type->accept_nokey(ask->private, sk2);
294
295 if (err)
296 goto unlock;
297
298 if (atomic_inc_return_relaxed(&ask->refcnt) == 1)
299 sock_hold(sk);
300 if (nokey) {
301 atomic_inc(&ask->nokey_refcnt);
302 atomic_set(&alg_sk(sk2)->nokey_refcnt, 1);
303 }
304 alg_sk(sk2)->parent = sk;
305 alg_sk(sk2)->type = type;
306
307 newsock->ops = type->ops;
308 newsock->state = SS_CONNECTED;
309
310 if (nokey)
311 newsock->ops = type->ops_nokey;
312
313 err = 0;
314
315unlock:
316 release_sock(sk);
317
318 return err;
319}
320EXPORT_SYMBOL_GPL(af_alg_accept);
321
322static int alg_accept(struct socket *sock, struct socket *newsock, int flags,
323 bool kern)
324{
325 return af_alg_accept(sock->sk, newsock, kern);
326}
327
328static const struct proto_ops alg_proto_ops = {
329 .family = PF_ALG,
330 .owner = THIS_MODULE,
331
332 .connect = sock_no_connect,
333 .socketpair = sock_no_socketpair,
334 .getname = sock_no_getname,
335 .ioctl = sock_no_ioctl,
336 .listen = sock_no_listen,
337 .shutdown = sock_no_shutdown,
338 .mmap = sock_no_mmap,
339 .sendpage = sock_no_sendpage,
340 .sendmsg = sock_no_sendmsg,
341 .recvmsg = sock_no_recvmsg,
342
343 .bind = alg_bind,
344 .release = af_alg_release,
345 .setsockopt = alg_setsockopt,
346 .accept = alg_accept,
347};
348
349static void alg_sock_destruct(struct sock *sk)
350{
351 struct alg_sock *ask = alg_sk(sk);
352
353 alg_do_release(ask->type, ask->private);
354}
355
356static int alg_create(struct net *net, struct socket *sock, int protocol,
357 int kern)
358{
359 struct sock *sk;
360 int err;
361
362 if (sock->type != SOCK_SEQPACKET)
363 return -ESOCKTNOSUPPORT;
364 if (protocol != 0)
365 return -EPROTONOSUPPORT;
366
367 err = -ENOMEM;
368 sk = sk_alloc(net, PF_ALG, GFP_KERNEL, &alg_proto, kern);
369 if (!sk)
370 goto out;
371
372 sock->ops = &alg_proto_ops;
373 sock_init_data(sock, sk);
374
375 sk->sk_destruct = alg_sock_destruct;
376
377 return 0;
378out:
379 return err;
380}
381
382static const struct net_proto_family alg_family = {
383 .family = PF_ALG,
384 .create = alg_create,
385 .owner = THIS_MODULE,
386};
387
388int af_alg_make_sg(struct af_alg_sgl *sgl, struct iov_iter *iter, int len)
389{
390 size_t off;
391 ssize_t n;
392 int npages, i;
393
394 n = iov_iter_get_pages(iter, sgl->pages, len, ALG_MAX_PAGES, &off);
395 if (n < 0)
396 return n;
397
398 npages = (off + n + PAGE_SIZE - 1) >> PAGE_SHIFT;
399 if (WARN_ON(npages == 0))
400 return -EINVAL;
401 /* Add one extra for linking */
402 sg_init_table(sgl->sg, npages + 1);
403
404 for (i = 0, len = n; i < npages; i++) {
405 int plen = min_t(int, len, PAGE_SIZE - off);
406
407 sg_set_page(sgl->sg + i, sgl->pages[i], plen, off);
408
409 off = 0;
410 len -= plen;
411 }
412 sg_mark_end(sgl->sg + npages - 1);
413 sgl->npages = npages;
414
415 return n;
416}
417EXPORT_SYMBOL_GPL(af_alg_make_sg);
418
419static void af_alg_link_sg(struct af_alg_sgl *sgl_prev,
420 struct af_alg_sgl *sgl_new)
421{
422 sg_unmark_end(sgl_prev->sg + sgl_prev->npages - 1);
423 sg_chain(sgl_prev->sg, sgl_prev->npages + 1, sgl_new->sg);
424}
425
426void af_alg_free_sg(struct af_alg_sgl *sgl)
427{
428 int i;
429
430 for (i = 0; i < sgl->npages; i++)
431 put_page(sgl->pages[i]);
432}
433EXPORT_SYMBOL_GPL(af_alg_free_sg);
434
435static int af_alg_cmsg_send(struct msghdr *msg, struct af_alg_control *con)
436{
437 struct cmsghdr *cmsg;
438
439 for_each_cmsghdr(cmsg, msg) {
440 if (!CMSG_OK(msg, cmsg))
441 return -EINVAL;
442 if (cmsg->cmsg_level != SOL_ALG)
443 continue;
444
445 switch (cmsg->cmsg_type) {
446 case ALG_SET_IV:
447 if (cmsg->cmsg_len < CMSG_LEN(sizeof(*con->iv)))
448 return -EINVAL;
449 con->iv = (void *)CMSG_DATA(cmsg);
450 if (cmsg->cmsg_len < CMSG_LEN(con->iv->ivlen +
451 sizeof(*con->iv)))
452 return -EINVAL;
453 break;
454
455 case ALG_SET_OP:
456 if (cmsg->cmsg_len < CMSG_LEN(sizeof(u32)))
457 return -EINVAL;
458 con->op = *(u32 *)CMSG_DATA(cmsg);
459 break;
460
461 case ALG_SET_AEAD_ASSOCLEN:
462 if (cmsg->cmsg_len < CMSG_LEN(sizeof(u32)))
463 return -EINVAL;
464 con->aead_assoclen = *(u32 *)CMSG_DATA(cmsg);
465 break;
466
467 default:
468 return -EINVAL;
469 }
470 }
471
472 return 0;
473}
474
475/**
476 * af_alg_alloc_tsgl - allocate the TX SGL
477 *
478 * @sk socket of connection to user space
479 * @return: 0 upon success, < 0 upon error
480 */
481static int af_alg_alloc_tsgl(struct sock *sk)
482{
483 struct alg_sock *ask = alg_sk(sk);
484 struct af_alg_ctx *ctx = ask->private;
485 struct af_alg_tsgl *sgl;
486 struct scatterlist *sg = NULL;
487
488 sgl = list_entry(ctx->tsgl_list.prev, struct af_alg_tsgl, list);
489 if (!list_empty(&ctx->tsgl_list))
490 sg = sgl->sg;
491
492 if (!sg || sgl->cur >= MAX_SGL_ENTS) {
493 sgl = sock_kmalloc(sk,
494 struct_size(sgl, sg, (MAX_SGL_ENTS + 1)),
495 GFP_KERNEL);
496 if (!sgl)
497 return -ENOMEM;
498
499 sg_init_table(sgl->sg, MAX_SGL_ENTS + 1);
500 sgl->cur = 0;
501
502 if (sg)
503 sg_chain(sg, MAX_SGL_ENTS + 1, sgl->sg);
504
505 list_add_tail(&sgl->list, &ctx->tsgl_list);
506 }
507
508 return 0;
509}
510
511/**
512 * aead_count_tsgl - Count number of TX SG entries
513 *
514 * The counting starts from the beginning of the SGL to @bytes. If
515 * an offset is provided, the counting of the SG entries starts at the offset.
516 *
517 * @sk socket of connection to user space
518 * @bytes Count the number of SG entries holding given number of bytes.
519 * @offset Start the counting of SG entries from the given offset.
520 * @return Number of TX SG entries found given the constraints
521 */
522unsigned int af_alg_count_tsgl(struct sock *sk, size_t bytes, size_t offset)
523{
524 const struct alg_sock *ask = alg_sk(sk);
525 const struct af_alg_ctx *ctx = ask->private;
526 const struct af_alg_tsgl *sgl;
527 unsigned int i;
528 unsigned int sgl_count = 0;
529
530 if (!bytes)
531 return 0;
532
533 list_for_each_entry(sgl, &ctx->tsgl_list, list) {
534 const struct scatterlist *sg = sgl->sg;
535
536 for (i = 0; i < sgl->cur; i++) {
537 size_t bytes_count;
538
539 /* Skip offset */
540 if (offset >= sg[i].length) {
541 offset -= sg[i].length;
542 bytes -= sg[i].length;
543 continue;
544 }
545
546 bytes_count = sg[i].length - offset;
547
548 offset = 0;
549 sgl_count++;
550
551 /* If we have seen requested number of bytes, stop */
552 if (bytes_count >= bytes)
553 return sgl_count;
554
555 bytes -= bytes_count;
556 }
557 }
558
559 return sgl_count;
560}
561EXPORT_SYMBOL_GPL(af_alg_count_tsgl);
562
563/**
564 * aead_pull_tsgl - Release the specified buffers from TX SGL
565 *
566 * If @dst is non-null, reassign the pages to dst. The caller must release
567 * the pages. If @dst_offset is given only reassign the pages to @dst starting
568 * at the @dst_offset (byte). The caller must ensure that @dst is large
569 * enough (e.g. by using af_alg_count_tsgl with the same offset).
570 *
571 * @sk socket of connection to user space
572 * @used Number of bytes to pull from TX SGL
573 * @dst If non-NULL, buffer is reassigned to dst SGL instead of releasing. The
574 * caller must release the buffers in dst.
575 * @dst_offset Reassign the TX SGL from given offset. All buffers before
576 * reaching the offset is released.
577 */
578void af_alg_pull_tsgl(struct sock *sk, size_t used, struct scatterlist *dst,
579 size_t dst_offset)
580{
581 struct alg_sock *ask = alg_sk(sk);
582 struct af_alg_ctx *ctx = ask->private;
583 struct af_alg_tsgl *sgl;
584 struct scatterlist *sg;
585 unsigned int i, j = 0;
586
587 while (!list_empty(&ctx->tsgl_list)) {
588 sgl = list_first_entry(&ctx->tsgl_list, struct af_alg_tsgl,
589 list);
590 sg = sgl->sg;
591
592 for (i = 0; i < sgl->cur; i++) {
593 size_t plen = min_t(size_t, used, sg[i].length);
594 struct page *page = sg_page(sg + i);
595
596 if (!page)
597 continue;
598
599 /*
600 * Assumption: caller created af_alg_count_tsgl(len)
601 * SG entries in dst.
602 */
603 if (dst) {
604 if (dst_offset >= plen) {
605 /* discard page before offset */
606 dst_offset -= plen;
607 } else {
608 /* reassign page to dst after offset */
609 get_page(page);
610 sg_set_page(dst + j, page,
611 plen - dst_offset,
612 sg[i].offset + dst_offset);
613 dst_offset = 0;
614 j++;
615 }
616 }
617
618 sg[i].length -= plen;
619 sg[i].offset += plen;
620
621 used -= plen;
622 ctx->used -= plen;
623
624 if (sg[i].length)
625 return;
626
627 put_page(page);
628 sg_assign_page(sg + i, NULL);
629 }
630
631 list_del(&sgl->list);
632 sock_kfree_s(sk, sgl, struct_size(sgl, sg, MAX_SGL_ENTS + 1));
633 }
634
635 if (!ctx->used)
636 ctx->merge = 0;
637 ctx->init = ctx->more;
638}
639EXPORT_SYMBOL_GPL(af_alg_pull_tsgl);
640
641/**
642 * af_alg_free_areq_sgls - Release TX and RX SGLs of the request
643 *
644 * @areq Request holding the TX and RX SGL
645 */
646static void af_alg_free_areq_sgls(struct af_alg_async_req *areq)
647{
648 struct sock *sk = areq->sk;
649 struct alg_sock *ask = alg_sk(sk);
650 struct af_alg_ctx *ctx = ask->private;
651 struct af_alg_rsgl *rsgl, *tmp;
652 struct scatterlist *tsgl;
653 struct scatterlist *sg;
654 unsigned int i;
655
656 list_for_each_entry_safe(rsgl, tmp, &areq->rsgl_list, list) {
657 atomic_sub(rsgl->sg_num_bytes, &ctx->rcvused);
658 af_alg_free_sg(&rsgl->sgl);
659 list_del(&rsgl->list);
660 if (rsgl != &areq->first_rsgl)
661 sock_kfree_s(sk, rsgl, sizeof(*rsgl));
662 }
663
664 tsgl = areq->tsgl;
665 if (tsgl) {
666 for_each_sg(tsgl, sg, areq->tsgl_entries, i) {
667 if (!sg_page(sg))
668 continue;
669 put_page(sg_page(sg));
670 }
671
672 sock_kfree_s(sk, tsgl, areq->tsgl_entries * sizeof(*tsgl));
673 }
674}
675
676/**
677 * af_alg_wait_for_wmem - wait for availability of writable memory
678 *
679 * @sk socket of connection to user space
680 * @flags If MSG_DONTWAIT is set, then only report if function would sleep
681 * @return 0 when writable memory is available, < 0 upon error
682 */
683static int af_alg_wait_for_wmem(struct sock *sk, unsigned int flags)
684{
685 DEFINE_WAIT_FUNC(wait, woken_wake_function);
686 int err = -ERESTARTSYS;
687 long timeout;
688
689 if (flags & MSG_DONTWAIT)
690 return -EAGAIN;
691
692 sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
693
694 add_wait_queue(sk_sleep(sk), &wait);
695 for (;;) {
696 if (signal_pending(current))
697 break;
698 timeout = MAX_SCHEDULE_TIMEOUT;
699 if (sk_wait_event(sk, &timeout, af_alg_writable(sk), &wait)) {
700 err = 0;
701 break;
702 }
703 }
704 remove_wait_queue(sk_sleep(sk), &wait);
705
706 return err;
707}
708
709/**
710 * af_alg_wmem_wakeup - wakeup caller when writable memory is available
711 *
712 * @sk socket of connection to user space
713 */
714void af_alg_wmem_wakeup(struct sock *sk)
715{
716 struct socket_wq *wq;
717
718 if (!af_alg_writable(sk))
719 return;
720
721 rcu_read_lock();
722 wq = rcu_dereference(sk->sk_wq);
723 if (skwq_has_sleeper(wq))
724 wake_up_interruptible_sync_poll(&wq->wait, EPOLLIN |
725 EPOLLRDNORM |
726 EPOLLRDBAND);
727 sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN);
728 rcu_read_unlock();
729}
730EXPORT_SYMBOL_GPL(af_alg_wmem_wakeup);
731
732/**
733 * af_alg_wait_for_data - wait for availability of TX data
734 *
735 * @sk socket of connection to user space
736 * @flags If MSG_DONTWAIT is set, then only report if function would sleep
737 * @min Set to minimum request size if partial requests are allowed.
738 * @return 0 when writable memory is available, < 0 upon error
739 */
740int af_alg_wait_for_data(struct sock *sk, unsigned flags, unsigned min)
741{
742 DEFINE_WAIT_FUNC(wait, woken_wake_function);
743 struct alg_sock *ask = alg_sk(sk);
744 struct af_alg_ctx *ctx = ask->private;
745 long timeout;
746 int err = -ERESTARTSYS;
747
748 if (flags & MSG_DONTWAIT)
749 return -EAGAIN;
750
751 sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk);
752
753 add_wait_queue(sk_sleep(sk), &wait);
754 for (;;) {
755 if (signal_pending(current))
756 break;
757 timeout = MAX_SCHEDULE_TIMEOUT;
758 if (sk_wait_event(sk, &timeout,
759 ctx->init && (!ctx->more ||
760 (min && ctx->used >= min)),
761 &wait)) {
762 err = 0;
763 break;
764 }
765 }
766 remove_wait_queue(sk_sleep(sk), &wait);
767
768 sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk);
769
770 return err;
771}
772EXPORT_SYMBOL_GPL(af_alg_wait_for_data);
773
774/**
775 * af_alg_data_wakeup - wakeup caller when new data can be sent to kernel
776 *
777 * @sk socket of connection to user space
778 */
779static void af_alg_data_wakeup(struct sock *sk)
780{
781 struct alg_sock *ask = alg_sk(sk);
782 struct af_alg_ctx *ctx = ask->private;
783 struct socket_wq *wq;
784
785 if (!ctx->used)
786 return;
787
788 rcu_read_lock();
789 wq = rcu_dereference(sk->sk_wq);
790 if (skwq_has_sleeper(wq))
791 wake_up_interruptible_sync_poll(&wq->wait, EPOLLOUT |
792 EPOLLRDNORM |
793 EPOLLRDBAND);
794 sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
795 rcu_read_unlock();
796}
797
798/**
799 * af_alg_sendmsg - implementation of sendmsg system call handler
800 *
801 * The sendmsg system call handler obtains the user data and stores it
802 * in ctx->tsgl_list. This implies allocation of the required numbers of
803 * struct af_alg_tsgl.
804 *
805 * In addition, the ctx is filled with the information sent via CMSG.
806 *
807 * @sock socket of connection to user space
808 * @msg message from user space
809 * @size size of message from user space
810 * @ivsize the size of the IV for the cipher operation to verify that the
811 * user-space-provided IV has the right size
812 * @return the number of copied data upon success, < 0 upon error
813 */
814int af_alg_sendmsg(struct socket *sock, struct msghdr *msg, size_t size,
815 unsigned int ivsize)
816{
817 struct sock *sk = sock->sk;
818 struct alg_sock *ask = alg_sk(sk);
819 struct af_alg_ctx *ctx = ask->private;
820 struct af_alg_tsgl *sgl;
821 struct af_alg_control con = {};
822 long copied = 0;
823 bool enc = false;
824 bool init = false;
825 int err = 0;
826
827 if (msg->msg_controllen) {
828 err = af_alg_cmsg_send(msg, &con);
829 if (err)
830 return err;
831
832 init = true;
833 switch (con.op) {
834 case ALG_OP_ENCRYPT:
835 enc = true;
836 break;
837 case ALG_OP_DECRYPT:
838 enc = false;
839 break;
840 default:
841 return -EINVAL;
842 }
843
844 if (con.iv && con.iv->ivlen != ivsize)
845 return -EINVAL;
846 }
847
848 lock_sock(sk);
849 if (ctx->init && !ctx->more) {
850 if (ctx->used) {
851 err = -EINVAL;
852 goto unlock;
853 }
854
855 pr_info_once(
856 "%s sent an empty control message without MSG_MORE.\n",
857 current->comm);
858 }
859 ctx->init = true;
860
861 if (init) {
862 ctx->enc = enc;
863 if (con.iv)
864 memcpy(ctx->iv, con.iv->iv, ivsize);
865
866 ctx->aead_assoclen = con.aead_assoclen;
867 }
868
869 while (size) {
870 struct scatterlist *sg;
871 size_t len = size;
872 size_t plen;
873
874 /* use the existing memory in an allocated page */
875 if (ctx->merge) {
876 sgl = list_entry(ctx->tsgl_list.prev,
877 struct af_alg_tsgl, list);
878 sg = sgl->sg + sgl->cur - 1;
879 len = min_t(size_t, len,
880 PAGE_SIZE - sg->offset - sg->length);
881
882 err = memcpy_from_msg(page_address(sg_page(sg)) +
883 sg->offset + sg->length,
884 msg, len);
885 if (err)
886 goto unlock;
887
888 sg->length += len;
889 ctx->merge = (sg->offset + sg->length) &
890 (PAGE_SIZE - 1);
891
892 ctx->used += len;
893 copied += len;
894 size -= len;
895 continue;
896 }
897
898 if (!af_alg_writable(sk)) {
899 err = af_alg_wait_for_wmem(sk, msg->msg_flags);
900 if (err)
901 goto unlock;
902 }
903
904 /* allocate a new page */
905 len = min_t(unsigned long, len, af_alg_sndbuf(sk));
906
907 err = af_alg_alloc_tsgl(sk);
908 if (err)
909 goto unlock;
910
911 sgl = list_entry(ctx->tsgl_list.prev, struct af_alg_tsgl,
912 list);
913 sg = sgl->sg;
914 if (sgl->cur)
915 sg_unmark_end(sg + sgl->cur - 1);
916
917 do {
918 unsigned int i = sgl->cur;
919
920 plen = min_t(size_t, len, PAGE_SIZE);
921
922 sg_assign_page(sg + i, alloc_page(GFP_KERNEL));
923 if (!sg_page(sg + i)) {
924 err = -ENOMEM;
925 goto unlock;
926 }
927
928 err = memcpy_from_msg(page_address(sg_page(sg + i)),
929 msg, plen);
930 if (err) {
931 __free_page(sg_page(sg + i));
932 sg_assign_page(sg + i, NULL);
933 goto unlock;
934 }
935
936 sg[i].length = plen;
937 len -= plen;
938 ctx->used += plen;
939 copied += plen;
940 size -= plen;
941 sgl->cur++;
942 } while (len && sgl->cur < MAX_SGL_ENTS);
943
944 if (!size)
945 sg_mark_end(sg + sgl->cur - 1);
946
947 ctx->merge = plen & (PAGE_SIZE - 1);
948 }
949
950 err = 0;
951
952 ctx->more = msg->msg_flags & MSG_MORE;
953
954unlock:
955 af_alg_data_wakeup(sk);
956 release_sock(sk);
957
958 return copied ?: err;
959}
960EXPORT_SYMBOL_GPL(af_alg_sendmsg);
961
962/**
963 * af_alg_sendpage - sendpage system call handler
964 *
965 * This is a generic implementation of sendpage to fill ctx->tsgl_list.
966 */
967ssize_t af_alg_sendpage(struct socket *sock, struct page *page,
968 int offset, size_t size, int flags)
969{
970 struct sock *sk = sock->sk;
971 struct alg_sock *ask = alg_sk(sk);
972 struct af_alg_ctx *ctx = ask->private;
973 struct af_alg_tsgl *sgl;
974 int err = -EINVAL;
975
976 if (flags & MSG_SENDPAGE_NOTLAST)
977 flags |= MSG_MORE;
978
979 lock_sock(sk);
980 if (!ctx->more && ctx->used)
981 goto unlock;
982
983 if (!size)
984 goto done;
985
986 if (!af_alg_writable(sk)) {
987 err = af_alg_wait_for_wmem(sk, flags);
988 if (err)
989 goto unlock;
990 }
991
992 err = af_alg_alloc_tsgl(sk);
993 if (err)
994 goto unlock;
995
996 ctx->merge = 0;
997 sgl = list_entry(ctx->tsgl_list.prev, struct af_alg_tsgl, list);
998
999 if (sgl->cur)
1000 sg_unmark_end(sgl->sg + sgl->cur - 1);
1001
1002 sg_mark_end(sgl->sg + sgl->cur);
1003
1004 get_page(page);
1005 sg_set_page(sgl->sg + sgl->cur, page, size, offset);
1006 sgl->cur++;
1007 ctx->used += size;
1008
1009done:
1010 ctx->more = flags & MSG_MORE;
1011
1012unlock:
1013 af_alg_data_wakeup(sk);
1014 release_sock(sk);
1015
1016 return err ?: size;
1017}
1018EXPORT_SYMBOL_GPL(af_alg_sendpage);
1019
1020/**
1021 * af_alg_free_resources - release resources required for crypto request
1022 */
1023void af_alg_free_resources(struct af_alg_async_req *areq)
1024{
1025 struct sock *sk = areq->sk;
1026
1027 af_alg_free_areq_sgls(areq);
1028 sock_kfree_s(sk, areq, areq->areqlen);
1029}
1030EXPORT_SYMBOL_GPL(af_alg_free_resources);
1031
1032/**
1033 * af_alg_async_cb - AIO callback handler
1034 *
1035 * This handler cleans up the struct af_alg_async_req upon completion of the
1036 * AIO operation.
1037 *
1038 * The number of bytes to be generated with the AIO operation must be set
1039 * in areq->outlen before the AIO callback handler is invoked.
1040 */
1041void af_alg_async_cb(struct crypto_async_request *_req, int err)
1042{
1043 struct af_alg_async_req *areq = _req->data;
1044 struct sock *sk = areq->sk;
1045 struct kiocb *iocb = areq->iocb;
1046 unsigned int resultlen;
1047
1048 /* Buffer size written by crypto operation. */
1049 resultlen = areq->outlen;
1050
1051 af_alg_free_resources(areq);
1052 sock_put(sk);
1053
1054 iocb->ki_complete(iocb, err ? err : (int)resultlen, 0);
1055}
1056EXPORT_SYMBOL_GPL(af_alg_async_cb);
1057
1058/**
1059 * af_alg_poll - poll system call handler
1060 */
1061__poll_t af_alg_poll(struct file *file, struct socket *sock,
1062 poll_table *wait)
1063{
1064 struct sock *sk = sock->sk;
1065 struct alg_sock *ask = alg_sk(sk);
1066 struct af_alg_ctx *ctx = ask->private;
1067 __poll_t mask;
1068
1069 sock_poll_wait(file, sock, wait);
1070 mask = 0;
1071
1072 if (!ctx->more || ctx->used)
1073 mask |= EPOLLIN | EPOLLRDNORM;
1074
1075 if (af_alg_writable(sk))
1076 mask |= EPOLLOUT | EPOLLWRNORM | EPOLLWRBAND;
1077
1078 return mask;
1079}
1080EXPORT_SYMBOL_GPL(af_alg_poll);
1081
1082/**
1083 * af_alg_alloc_areq - allocate struct af_alg_async_req
1084 *
1085 * @sk socket of connection to user space
1086 * @areqlen size of struct af_alg_async_req + crypto_*_reqsize
1087 * @return allocated data structure or ERR_PTR upon error
1088 */
1089struct af_alg_async_req *af_alg_alloc_areq(struct sock *sk,
1090 unsigned int areqlen)
1091{
1092 struct af_alg_async_req *areq = sock_kmalloc(sk, areqlen, GFP_KERNEL);
1093
1094 if (unlikely(!areq))
1095 return ERR_PTR(-ENOMEM);
1096
1097 areq->areqlen = areqlen;
1098 areq->sk = sk;
1099 areq->last_rsgl = NULL;
1100 INIT_LIST_HEAD(&areq->rsgl_list);
1101 areq->tsgl = NULL;
1102 areq->tsgl_entries = 0;
1103
1104 return areq;
1105}
1106EXPORT_SYMBOL_GPL(af_alg_alloc_areq);
1107
1108/**
1109 * af_alg_get_rsgl - create the RX SGL for the output data from the crypto
1110 * operation
1111 *
1112 * @sk socket of connection to user space
1113 * @msg user space message
1114 * @flags flags used to invoke recvmsg with
1115 * @areq instance of the cryptographic request that will hold the RX SGL
1116 * @maxsize maximum number of bytes to be pulled from user space
1117 * @outlen number of bytes in the RX SGL
1118 * @return 0 on success, < 0 upon error
1119 */
1120int af_alg_get_rsgl(struct sock *sk, struct msghdr *msg, int flags,
1121 struct af_alg_async_req *areq, size_t maxsize,
1122 size_t *outlen)
1123{
1124 struct alg_sock *ask = alg_sk(sk);
1125 struct af_alg_ctx *ctx = ask->private;
1126 size_t len = 0;
1127
1128 while (maxsize > len && msg_data_left(msg)) {
1129 struct af_alg_rsgl *rsgl;
1130 size_t seglen;
1131 int err;
1132
1133 /* limit the amount of readable buffers */
1134 if (!af_alg_readable(sk))
1135 break;
1136
1137 seglen = min_t(size_t, (maxsize - len),
1138 msg_data_left(msg));
1139
1140 if (list_empty(&areq->rsgl_list)) {
1141 rsgl = &areq->first_rsgl;
1142 } else {
1143 rsgl = sock_kmalloc(sk, sizeof(*rsgl), GFP_KERNEL);
1144 if (unlikely(!rsgl))
1145 return -ENOMEM;
1146 }
1147
1148 rsgl->sgl.npages = 0;
1149 list_add_tail(&rsgl->list, &areq->rsgl_list);
1150
1151 /* make one iovec available as scatterlist */
1152 err = af_alg_make_sg(&rsgl->sgl, &msg->msg_iter, seglen);
1153 if (err < 0) {
1154 rsgl->sg_num_bytes = 0;
1155 return err;
1156 }
1157
1158 /* chain the new scatterlist with previous one */
1159 if (areq->last_rsgl)
1160 af_alg_link_sg(&areq->last_rsgl->sgl, &rsgl->sgl);
1161
1162 areq->last_rsgl = rsgl;
1163 len += err;
1164 atomic_add(err, &ctx->rcvused);
1165 rsgl->sg_num_bytes = err;
1166 iov_iter_advance(&msg->msg_iter, err);
1167 }
1168
1169 *outlen = len;
1170 return 0;
1171}
1172EXPORT_SYMBOL_GPL(af_alg_get_rsgl);
1173
1174static int __init af_alg_init(void)
1175{
1176 int err = proto_register(&alg_proto, 0);
1177
1178 if (err)
1179 goto out;
1180
1181 err = sock_register(&alg_family);
1182 if (err != 0)
1183 goto out_unregister_proto;
1184
1185out:
1186 return err;
1187
1188out_unregister_proto:
1189 proto_unregister(&alg_proto);
1190 goto out;
1191}
1192
1193static void __exit af_alg_exit(void)
1194{
1195 sock_unregister(PF_ALG);
1196 proto_unregister(&alg_proto);
1197}
1198
1199module_init(af_alg_init);
1200module_exit(af_alg_exit);
1201MODULE_LICENSE("GPL");
1202MODULE_ALIAS_NETPROTO(AF_ALG);
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * af_alg: User-space algorithm interface
4 *
5 * This file provides the user-space API for algorithms.
6 *
7 * Copyright (c) 2010 Herbert Xu <herbert@gondor.apana.org.au>
8 */
9
10#include <linux/atomic.h>
11#include <crypto/if_alg.h>
12#include <linux/crypto.h>
13#include <linux/init.h>
14#include <linux/kernel.h>
15#include <linux/key.h>
16#include <linux/key-type.h>
17#include <linux/list.h>
18#include <linux/module.h>
19#include <linux/net.h>
20#include <linux/rwsem.h>
21#include <linux/sched.h>
22#include <linux/sched/signal.h>
23#include <linux/security.h>
24#include <linux/string.h>
25#include <keys/user-type.h>
26#include <keys/trusted-type.h>
27#include <keys/encrypted-type.h>
28
29struct alg_type_list {
30 const struct af_alg_type *type;
31 struct list_head list;
32};
33
34static struct proto alg_proto = {
35 .name = "ALG",
36 .owner = THIS_MODULE,
37 .obj_size = sizeof(struct alg_sock),
38};
39
40static LIST_HEAD(alg_types);
41static DECLARE_RWSEM(alg_types_sem);
42
43static const struct af_alg_type *alg_get_type(const char *name)
44{
45 const struct af_alg_type *type = ERR_PTR(-ENOENT);
46 struct alg_type_list *node;
47
48 down_read(&alg_types_sem);
49 list_for_each_entry(node, &alg_types, list) {
50 if (strcmp(node->type->name, name))
51 continue;
52
53 if (try_module_get(node->type->owner))
54 type = node->type;
55 break;
56 }
57 up_read(&alg_types_sem);
58
59 return type;
60}
61
62int af_alg_register_type(const struct af_alg_type *type)
63{
64 struct alg_type_list *node;
65 int err = -EEXIST;
66
67 down_write(&alg_types_sem);
68 list_for_each_entry(node, &alg_types, list) {
69 if (!strcmp(node->type->name, type->name))
70 goto unlock;
71 }
72
73 node = kmalloc(sizeof(*node), GFP_KERNEL);
74 err = -ENOMEM;
75 if (!node)
76 goto unlock;
77
78 type->ops->owner = THIS_MODULE;
79 if (type->ops_nokey)
80 type->ops_nokey->owner = THIS_MODULE;
81 node->type = type;
82 list_add(&node->list, &alg_types);
83 err = 0;
84
85unlock:
86 up_write(&alg_types_sem);
87
88 return err;
89}
90EXPORT_SYMBOL_GPL(af_alg_register_type);
91
92int af_alg_unregister_type(const struct af_alg_type *type)
93{
94 struct alg_type_list *node;
95 int err = -ENOENT;
96
97 down_write(&alg_types_sem);
98 list_for_each_entry(node, &alg_types, list) {
99 if (strcmp(node->type->name, type->name))
100 continue;
101
102 list_del(&node->list);
103 kfree(node);
104 err = 0;
105 break;
106 }
107 up_write(&alg_types_sem);
108
109 return err;
110}
111EXPORT_SYMBOL_GPL(af_alg_unregister_type);
112
113static void alg_do_release(const struct af_alg_type *type, void *private)
114{
115 if (!type)
116 return;
117
118 type->release(private);
119 module_put(type->owner);
120}
121
122int af_alg_release(struct socket *sock)
123{
124 if (sock->sk) {
125 sock_put(sock->sk);
126 sock->sk = NULL;
127 }
128 return 0;
129}
130EXPORT_SYMBOL_GPL(af_alg_release);
131
132void af_alg_release_parent(struct sock *sk)
133{
134 struct alg_sock *ask = alg_sk(sk);
135 unsigned int nokey = atomic_read(&ask->nokey_refcnt);
136
137 sk = ask->parent;
138 ask = alg_sk(sk);
139
140 if (nokey)
141 atomic_dec(&ask->nokey_refcnt);
142
143 if (atomic_dec_and_test(&ask->refcnt))
144 sock_put(sk);
145}
146EXPORT_SYMBOL_GPL(af_alg_release_parent);
147
148static int alg_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
149{
150 const u32 allowed = CRYPTO_ALG_KERN_DRIVER_ONLY;
151 struct sock *sk = sock->sk;
152 struct alg_sock *ask = alg_sk(sk);
153 struct sockaddr_alg_new *sa = (void *)uaddr;
154 const struct af_alg_type *type;
155 void *private;
156 int err;
157
158 if (sock->state == SS_CONNECTED)
159 return -EINVAL;
160
161 BUILD_BUG_ON(offsetof(struct sockaddr_alg_new, salg_name) !=
162 offsetof(struct sockaddr_alg, salg_name));
163 BUILD_BUG_ON(offsetof(struct sockaddr_alg, salg_name) != sizeof(*sa));
164
165 if (addr_len < sizeof(*sa) + 1)
166 return -EINVAL;
167
168 /* If caller uses non-allowed flag, return error. */
169 if ((sa->salg_feat & ~allowed) || (sa->salg_mask & ~allowed))
170 return -EINVAL;
171
172 sa->salg_type[sizeof(sa->salg_type) - 1] = 0;
173 sa->salg_name[addr_len - sizeof(*sa) - 1] = 0;
174
175 type = alg_get_type(sa->salg_type);
176 if (PTR_ERR(type) == -ENOENT) {
177 request_module("algif-%s", sa->salg_type);
178 type = alg_get_type(sa->salg_type);
179 }
180
181 if (IS_ERR(type))
182 return PTR_ERR(type);
183
184 private = type->bind(sa->salg_name, sa->salg_feat, sa->salg_mask);
185 if (IS_ERR(private)) {
186 module_put(type->owner);
187 return PTR_ERR(private);
188 }
189
190 err = -EBUSY;
191 lock_sock(sk);
192 if (atomic_read(&ask->refcnt))
193 goto unlock;
194
195 swap(ask->type, type);
196 swap(ask->private, private);
197
198 err = 0;
199
200unlock:
201 release_sock(sk);
202
203 alg_do_release(type, private);
204
205 return err;
206}
207
208static int alg_setkey(struct sock *sk, sockptr_t ukey, unsigned int keylen)
209{
210 struct alg_sock *ask = alg_sk(sk);
211 const struct af_alg_type *type = ask->type;
212 u8 *key;
213 int err;
214
215 key = sock_kmalloc(sk, keylen, GFP_KERNEL);
216 if (!key)
217 return -ENOMEM;
218
219 err = -EFAULT;
220 if (copy_from_sockptr(key, ukey, keylen))
221 goto out;
222
223 err = type->setkey(ask->private, key, keylen);
224
225out:
226 sock_kzfree_s(sk, key, keylen);
227
228 return err;
229}
230
231#ifdef CONFIG_KEYS
232
233static const u8 *key_data_ptr_user(const struct key *key,
234 unsigned int *datalen)
235{
236 const struct user_key_payload *ukp;
237
238 ukp = user_key_payload_locked(key);
239 if (IS_ERR_OR_NULL(ukp))
240 return ERR_PTR(-EKEYREVOKED);
241
242 *datalen = key->datalen;
243
244 return ukp->data;
245}
246
247static const u8 *key_data_ptr_encrypted(const struct key *key,
248 unsigned int *datalen)
249{
250 const struct encrypted_key_payload *ekp;
251
252 ekp = dereference_key_locked(key);
253 if (IS_ERR_OR_NULL(ekp))
254 return ERR_PTR(-EKEYREVOKED);
255
256 *datalen = ekp->decrypted_datalen;
257
258 return ekp->decrypted_data;
259}
260
261static const u8 *key_data_ptr_trusted(const struct key *key,
262 unsigned int *datalen)
263{
264 const struct trusted_key_payload *tkp;
265
266 tkp = dereference_key_locked(key);
267 if (IS_ERR_OR_NULL(tkp))
268 return ERR_PTR(-EKEYREVOKED);
269
270 *datalen = tkp->key_len;
271
272 return tkp->key;
273}
274
275static struct key *lookup_key(key_serial_t serial)
276{
277 key_ref_t key_ref;
278
279 key_ref = lookup_user_key(serial, 0, KEY_NEED_SEARCH);
280 if (IS_ERR(key_ref))
281 return ERR_CAST(key_ref);
282
283 return key_ref_to_ptr(key_ref);
284}
285
286static int alg_setkey_by_key_serial(struct alg_sock *ask, sockptr_t optval,
287 unsigned int optlen)
288{
289 const struct af_alg_type *type = ask->type;
290 u8 *key_data = NULL;
291 unsigned int key_datalen;
292 key_serial_t serial;
293 struct key *key;
294 const u8 *ret;
295 int err;
296
297 if (optlen != sizeof(serial))
298 return -EINVAL;
299
300 if (copy_from_sockptr(&serial, optval, optlen))
301 return -EFAULT;
302
303 key = lookup_key(serial);
304 if (IS_ERR(key))
305 return PTR_ERR(key);
306
307 down_read(&key->sem);
308
309 ret = ERR_PTR(-ENOPROTOOPT);
310 if (!strcmp(key->type->name, "user") ||
311 !strcmp(key->type->name, "logon")) {
312 ret = key_data_ptr_user(key, &key_datalen);
313 } else if (IS_REACHABLE(CONFIG_ENCRYPTED_KEYS) &&
314 !strcmp(key->type->name, "encrypted")) {
315 ret = key_data_ptr_encrypted(key, &key_datalen);
316 } else if (IS_REACHABLE(CONFIG_TRUSTED_KEYS) &&
317 !strcmp(key->type->name, "trusted")) {
318 ret = key_data_ptr_trusted(key, &key_datalen);
319 }
320
321 if (IS_ERR(ret)) {
322 up_read(&key->sem);
323 return PTR_ERR(ret);
324 }
325
326 key_data = sock_kmalloc(&ask->sk, key_datalen, GFP_KERNEL);
327 if (!key_data) {
328 up_read(&key->sem);
329 return -ENOMEM;
330 }
331
332 memcpy(key_data, ret, key_datalen);
333
334 up_read(&key->sem);
335
336 err = type->setkey(ask->private, key_data, key_datalen);
337
338 sock_kzfree_s(&ask->sk, key_data, key_datalen);
339
340 return err;
341}
342
343#else
344
345static inline int alg_setkey_by_key_serial(struct alg_sock *ask,
346 sockptr_t optval,
347 unsigned int optlen)
348{
349 return -ENOPROTOOPT;
350}
351
352#endif
353
354static int alg_setsockopt(struct socket *sock, int level, int optname,
355 sockptr_t optval, unsigned int optlen)
356{
357 struct sock *sk = sock->sk;
358 struct alg_sock *ask = alg_sk(sk);
359 const struct af_alg_type *type;
360 int err = -EBUSY;
361
362 lock_sock(sk);
363 if (atomic_read(&ask->refcnt) != atomic_read(&ask->nokey_refcnt))
364 goto unlock;
365
366 type = ask->type;
367
368 err = -ENOPROTOOPT;
369 if (level != SOL_ALG || !type)
370 goto unlock;
371
372 switch (optname) {
373 case ALG_SET_KEY:
374 case ALG_SET_KEY_BY_KEY_SERIAL:
375 if (sock->state == SS_CONNECTED)
376 goto unlock;
377 if (!type->setkey)
378 goto unlock;
379
380 if (optname == ALG_SET_KEY_BY_KEY_SERIAL)
381 err = alg_setkey_by_key_serial(ask, optval, optlen);
382 else
383 err = alg_setkey(sk, optval, optlen);
384 break;
385 case ALG_SET_AEAD_AUTHSIZE:
386 if (sock->state == SS_CONNECTED)
387 goto unlock;
388 if (!type->setauthsize)
389 goto unlock;
390 err = type->setauthsize(ask->private, optlen);
391 break;
392 case ALG_SET_DRBG_ENTROPY:
393 if (sock->state == SS_CONNECTED)
394 goto unlock;
395 if (!type->setentropy)
396 goto unlock;
397
398 err = type->setentropy(ask->private, optval, optlen);
399 }
400
401unlock:
402 release_sock(sk);
403
404 return err;
405}
406
407int af_alg_accept(struct sock *sk, struct socket *newsock, bool kern)
408{
409 struct alg_sock *ask = alg_sk(sk);
410 const struct af_alg_type *type;
411 struct sock *sk2;
412 unsigned int nokey;
413 int err;
414
415 lock_sock(sk);
416 type = ask->type;
417
418 err = -EINVAL;
419 if (!type)
420 goto unlock;
421
422 sk2 = sk_alloc(sock_net(sk), PF_ALG, GFP_KERNEL, &alg_proto, kern);
423 err = -ENOMEM;
424 if (!sk2)
425 goto unlock;
426
427 sock_init_data(newsock, sk2);
428 security_sock_graft(sk2, newsock);
429 security_sk_clone(sk, sk2);
430
431 /*
432 * newsock->ops assigned here to allow type->accept call to override
433 * them when required.
434 */
435 newsock->ops = type->ops;
436 err = type->accept(ask->private, sk2);
437
438 nokey = err == -ENOKEY;
439 if (nokey && type->accept_nokey)
440 err = type->accept_nokey(ask->private, sk2);
441
442 if (err)
443 goto unlock;
444
445 if (atomic_inc_return_relaxed(&ask->refcnt) == 1)
446 sock_hold(sk);
447 if (nokey) {
448 atomic_inc(&ask->nokey_refcnt);
449 atomic_set(&alg_sk(sk2)->nokey_refcnt, 1);
450 }
451 alg_sk(sk2)->parent = sk;
452 alg_sk(sk2)->type = type;
453
454 newsock->state = SS_CONNECTED;
455
456 if (nokey)
457 newsock->ops = type->ops_nokey;
458
459 err = 0;
460
461unlock:
462 release_sock(sk);
463
464 return err;
465}
466EXPORT_SYMBOL_GPL(af_alg_accept);
467
468static int alg_accept(struct socket *sock, struct socket *newsock, int flags,
469 bool kern)
470{
471 return af_alg_accept(sock->sk, newsock, kern);
472}
473
474static const struct proto_ops alg_proto_ops = {
475 .family = PF_ALG,
476 .owner = THIS_MODULE,
477
478 .connect = sock_no_connect,
479 .socketpair = sock_no_socketpair,
480 .getname = sock_no_getname,
481 .ioctl = sock_no_ioctl,
482 .listen = sock_no_listen,
483 .shutdown = sock_no_shutdown,
484 .mmap = sock_no_mmap,
485 .sendpage = sock_no_sendpage,
486 .sendmsg = sock_no_sendmsg,
487 .recvmsg = sock_no_recvmsg,
488
489 .bind = alg_bind,
490 .release = af_alg_release,
491 .setsockopt = alg_setsockopt,
492 .accept = alg_accept,
493};
494
495static void alg_sock_destruct(struct sock *sk)
496{
497 struct alg_sock *ask = alg_sk(sk);
498
499 alg_do_release(ask->type, ask->private);
500}
501
502static int alg_create(struct net *net, struct socket *sock, int protocol,
503 int kern)
504{
505 struct sock *sk;
506 int err;
507
508 if (sock->type != SOCK_SEQPACKET)
509 return -ESOCKTNOSUPPORT;
510 if (protocol != 0)
511 return -EPROTONOSUPPORT;
512
513 err = -ENOMEM;
514 sk = sk_alloc(net, PF_ALG, GFP_KERNEL, &alg_proto, kern);
515 if (!sk)
516 goto out;
517
518 sock->ops = &alg_proto_ops;
519 sock_init_data(sock, sk);
520
521 sk->sk_destruct = alg_sock_destruct;
522
523 return 0;
524out:
525 return err;
526}
527
528static const struct net_proto_family alg_family = {
529 .family = PF_ALG,
530 .create = alg_create,
531 .owner = THIS_MODULE,
532};
533
534int af_alg_make_sg(struct af_alg_sgl *sgl, struct iov_iter *iter, int len)
535{
536 size_t off;
537 ssize_t n;
538 int npages, i;
539
540 n = iov_iter_get_pages2(iter, sgl->pages, len, ALG_MAX_PAGES, &off);
541 if (n < 0)
542 return n;
543
544 npages = DIV_ROUND_UP(off + n, PAGE_SIZE);
545 if (WARN_ON(npages == 0))
546 return -EINVAL;
547 /* Add one extra for linking */
548 sg_init_table(sgl->sg, npages + 1);
549
550 for (i = 0, len = n; i < npages; i++) {
551 int plen = min_t(int, len, PAGE_SIZE - off);
552
553 sg_set_page(sgl->sg + i, sgl->pages[i], plen, off);
554
555 off = 0;
556 len -= plen;
557 }
558 sg_mark_end(sgl->sg + npages - 1);
559 sgl->npages = npages;
560
561 return n;
562}
563EXPORT_SYMBOL_GPL(af_alg_make_sg);
564
565static void af_alg_link_sg(struct af_alg_sgl *sgl_prev,
566 struct af_alg_sgl *sgl_new)
567{
568 sg_unmark_end(sgl_prev->sg + sgl_prev->npages - 1);
569 sg_chain(sgl_prev->sg, sgl_prev->npages + 1, sgl_new->sg);
570}
571
572void af_alg_free_sg(struct af_alg_sgl *sgl)
573{
574 int i;
575
576 for (i = 0; i < sgl->npages; i++)
577 put_page(sgl->pages[i]);
578}
579EXPORT_SYMBOL_GPL(af_alg_free_sg);
580
581static int af_alg_cmsg_send(struct msghdr *msg, struct af_alg_control *con)
582{
583 struct cmsghdr *cmsg;
584
585 for_each_cmsghdr(cmsg, msg) {
586 if (!CMSG_OK(msg, cmsg))
587 return -EINVAL;
588 if (cmsg->cmsg_level != SOL_ALG)
589 continue;
590
591 switch (cmsg->cmsg_type) {
592 case ALG_SET_IV:
593 if (cmsg->cmsg_len < CMSG_LEN(sizeof(*con->iv)))
594 return -EINVAL;
595 con->iv = (void *)CMSG_DATA(cmsg);
596 if (cmsg->cmsg_len < CMSG_LEN(con->iv->ivlen +
597 sizeof(*con->iv)))
598 return -EINVAL;
599 break;
600
601 case ALG_SET_OP:
602 if (cmsg->cmsg_len < CMSG_LEN(sizeof(u32)))
603 return -EINVAL;
604 con->op = *(u32 *)CMSG_DATA(cmsg);
605 break;
606
607 case ALG_SET_AEAD_ASSOCLEN:
608 if (cmsg->cmsg_len < CMSG_LEN(sizeof(u32)))
609 return -EINVAL;
610 con->aead_assoclen = *(u32 *)CMSG_DATA(cmsg);
611 break;
612
613 default:
614 return -EINVAL;
615 }
616 }
617
618 return 0;
619}
620
621/**
622 * af_alg_alloc_tsgl - allocate the TX SGL
623 *
624 * @sk: socket of connection to user space
625 * Return: 0 upon success, < 0 upon error
626 */
627static int af_alg_alloc_tsgl(struct sock *sk)
628{
629 struct alg_sock *ask = alg_sk(sk);
630 struct af_alg_ctx *ctx = ask->private;
631 struct af_alg_tsgl *sgl;
632 struct scatterlist *sg = NULL;
633
634 sgl = list_entry(ctx->tsgl_list.prev, struct af_alg_tsgl, list);
635 if (!list_empty(&ctx->tsgl_list))
636 sg = sgl->sg;
637
638 if (!sg || sgl->cur >= MAX_SGL_ENTS) {
639 sgl = sock_kmalloc(sk,
640 struct_size(sgl, sg, (MAX_SGL_ENTS + 1)),
641 GFP_KERNEL);
642 if (!sgl)
643 return -ENOMEM;
644
645 sg_init_table(sgl->sg, MAX_SGL_ENTS + 1);
646 sgl->cur = 0;
647
648 if (sg)
649 sg_chain(sg, MAX_SGL_ENTS + 1, sgl->sg);
650
651 list_add_tail(&sgl->list, &ctx->tsgl_list);
652 }
653
654 return 0;
655}
656
657/**
658 * af_alg_count_tsgl - Count number of TX SG entries
659 *
660 * The counting starts from the beginning of the SGL to @bytes. If
661 * an @offset is provided, the counting of the SG entries starts at the @offset.
662 *
663 * @sk: socket of connection to user space
664 * @bytes: Count the number of SG entries holding given number of bytes.
665 * @offset: Start the counting of SG entries from the given offset.
666 * Return: Number of TX SG entries found given the constraints
667 */
668unsigned int af_alg_count_tsgl(struct sock *sk, size_t bytes, size_t offset)
669{
670 const struct alg_sock *ask = alg_sk(sk);
671 const struct af_alg_ctx *ctx = ask->private;
672 const struct af_alg_tsgl *sgl;
673 unsigned int i;
674 unsigned int sgl_count = 0;
675
676 if (!bytes)
677 return 0;
678
679 list_for_each_entry(sgl, &ctx->tsgl_list, list) {
680 const struct scatterlist *sg = sgl->sg;
681
682 for (i = 0; i < sgl->cur; i++) {
683 size_t bytes_count;
684
685 /* Skip offset */
686 if (offset >= sg[i].length) {
687 offset -= sg[i].length;
688 bytes -= sg[i].length;
689 continue;
690 }
691
692 bytes_count = sg[i].length - offset;
693
694 offset = 0;
695 sgl_count++;
696
697 /* If we have seen requested number of bytes, stop */
698 if (bytes_count >= bytes)
699 return sgl_count;
700
701 bytes -= bytes_count;
702 }
703 }
704
705 return sgl_count;
706}
707EXPORT_SYMBOL_GPL(af_alg_count_tsgl);
708
709/**
710 * af_alg_pull_tsgl - Release the specified buffers from TX SGL
711 *
712 * If @dst is non-null, reassign the pages to @dst. The caller must release
713 * the pages. If @dst_offset is given only reassign the pages to @dst starting
714 * at the @dst_offset (byte). The caller must ensure that @dst is large
715 * enough (e.g. by using af_alg_count_tsgl with the same offset).
716 *
717 * @sk: socket of connection to user space
718 * @used: Number of bytes to pull from TX SGL
719 * @dst: If non-NULL, buffer is reassigned to dst SGL instead of releasing. The
720 * caller must release the buffers in dst.
721 * @dst_offset: Reassign the TX SGL from given offset. All buffers before
722 * reaching the offset is released.
723 */
724void af_alg_pull_tsgl(struct sock *sk, size_t used, struct scatterlist *dst,
725 size_t dst_offset)
726{
727 struct alg_sock *ask = alg_sk(sk);
728 struct af_alg_ctx *ctx = ask->private;
729 struct af_alg_tsgl *sgl;
730 struct scatterlist *sg;
731 unsigned int i, j = 0;
732
733 while (!list_empty(&ctx->tsgl_list)) {
734 sgl = list_first_entry(&ctx->tsgl_list, struct af_alg_tsgl,
735 list);
736 sg = sgl->sg;
737
738 for (i = 0; i < sgl->cur; i++) {
739 size_t plen = min_t(size_t, used, sg[i].length);
740 struct page *page = sg_page(sg + i);
741
742 if (!page)
743 continue;
744
745 /*
746 * Assumption: caller created af_alg_count_tsgl(len)
747 * SG entries in dst.
748 */
749 if (dst) {
750 if (dst_offset >= plen) {
751 /* discard page before offset */
752 dst_offset -= plen;
753 } else {
754 /* reassign page to dst after offset */
755 get_page(page);
756 sg_set_page(dst + j, page,
757 plen - dst_offset,
758 sg[i].offset + dst_offset);
759 dst_offset = 0;
760 j++;
761 }
762 }
763
764 sg[i].length -= plen;
765 sg[i].offset += plen;
766
767 used -= plen;
768 ctx->used -= plen;
769
770 if (sg[i].length)
771 return;
772
773 put_page(page);
774 sg_assign_page(sg + i, NULL);
775 }
776
777 list_del(&sgl->list);
778 sock_kfree_s(sk, sgl, struct_size(sgl, sg, MAX_SGL_ENTS + 1));
779 }
780
781 if (!ctx->used)
782 ctx->merge = 0;
783 ctx->init = ctx->more;
784}
785EXPORT_SYMBOL_GPL(af_alg_pull_tsgl);
786
787/**
788 * af_alg_free_areq_sgls - Release TX and RX SGLs of the request
789 *
790 * @areq: Request holding the TX and RX SGL
791 */
792static void af_alg_free_areq_sgls(struct af_alg_async_req *areq)
793{
794 struct sock *sk = areq->sk;
795 struct alg_sock *ask = alg_sk(sk);
796 struct af_alg_ctx *ctx = ask->private;
797 struct af_alg_rsgl *rsgl, *tmp;
798 struct scatterlist *tsgl;
799 struct scatterlist *sg;
800 unsigned int i;
801
802 list_for_each_entry_safe(rsgl, tmp, &areq->rsgl_list, list) {
803 atomic_sub(rsgl->sg_num_bytes, &ctx->rcvused);
804 af_alg_free_sg(&rsgl->sgl);
805 list_del(&rsgl->list);
806 if (rsgl != &areq->first_rsgl)
807 sock_kfree_s(sk, rsgl, sizeof(*rsgl));
808 }
809
810 tsgl = areq->tsgl;
811 if (tsgl) {
812 for_each_sg(tsgl, sg, areq->tsgl_entries, i) {
813 if (!sg_page(sg))
814 continue;
815 put_page(sg_page(sg));
816 }
817
818 sock_kfree_s(sk, tsgl, areq->tsgl_entries * sizeof(*tsgl));
819 }
820}
821
822/**
823 * af_alg_wait_for_wmem - wait for availability of writable memory
824 *
825 * @sk: socket of connection to user space
826 * @flags: If MSG_DONTWAIT is set, then only report if function would sleep
827 * Return: 0 when writable memory is available, < 0 upon error
828 */
829static int af_alg_wait_for_wmem(struct sock *sk, unsigned int flags)
830{
831 DEFINE_WAIT_FUNC(wait, woken_wake_function);
832 int err = -ERESTARTSYS;
833 long timeout;
834
835 if (flags & MSG_DONTWAIT)
836 return -EAGAIN;
837
838 sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
839
840 add_wait_queue(sk_sleep(sk), &wait);
841 for (;;) {
842 if (signal_pending(current))
843 break;
844 timeout = MAX_SCHEDULE_TIMEOUT;
845 if (sk_wait_event(sk, &timeout, af_alg_writable(sk), &wait)) {
846 err = 0;
847 break;
848 }
849 }
850 remove_wait_queue(sk_sleep(sk), &wait);
851
852 return err;
853}
854
855/**
856 * af_alg_wmem_wakeup - wakeup caller when writable memory is available
857 *
858 * @sk: socket of connection to user space
859 */
860void af_alg_wmem_wakeup(struct sock *sk)
861{
862 struct socket_wq *wq;
863
864 if (!af_alg_writable(sk))
865 return;
866
867 rcu_read_lock();
868 wq = rcu_dereference(sk->sk_wq);
869 if (skwq_has_sleeper(wq))
870 wake_up_interruptible_sync_poll(&wq->wait, EPOLLIN |
871 EPOLLRDNORM |
872 EPOLLRDBAND);
873 sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN);
874 rcu_read_unlock();
875}
876EXPORT_SYMBOL_GPL(af_alg_wmem_wakeup);
877
878/**
879 * af_alg_wait_for_data - wait for availability of TX data
880 *
881 * @sk: socket of connection to user space
882 * @flags: If MSG_DONTWAIT is set, then only report if function would sleep
883 * @min: Set to minimum request size if partial requests are allowed.
884 * Return: 0 when writable memory is available, < 0 upon error
885 */
886int af_alg_wait_for_data(struct sock *sk, unsigned flags, unsigned min)
887{
888 DEFINE_WAIT_FUNC(wait, woken_wake_function);
889 struct alg_sock *ask = alg_sk(sk);
890 struct af_alg_ctx *ctx = ask->private;
891 long timeout;
892 int err = -ERESTARTSYS;
893
894 if (flags & MSG_DONTWAIT)
895 return -EAGAIN;
896
897 sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk);
898
899 add_wait_queue(sk_sleep(sk), &wait);
900 for (;;) {
901 if (signal_pending(current))
902 break;
903 timeout = MAX_SCHEDULE_TIMEOUT;
904 if (sk_wait_event(sk, &timeout,
905 ctx->init && (!ctx->more ||
906 (min && ctx->used >= min)),
907 &wait)) {
908 err = 0;
909 break;
910 }
911 }
912 remove_wait_queue(sk_sleep(sk), &wait);
913
914 sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk);
915
916 return err;
917}
918EXPORT_SYMBOL_GPL(af_alg_wait_for_data);
919
920/**
921 * af_alg_data_wakeup - wakeup caller when new data can be sent to kernel
922 *
923 * @sk: socket of connection to user space
924 */
925static void af_alg_data_wakeup(struct sock *sk)
926{
927 struct alg_sock *ask = alg_sk(sk);
928 struct af_alg_ctx *ctx = ask->private;
929 struct socket_wq *wq;
930
931 if (!ctx->used)
932 return;
933
934 rcu_read_lock();
935 wq = rcu_dereference(sk->sk_wq);
936 if (skwq_has_sleeper(wq))
937 wake_up_interruptible_sync_poll(&wq->wait, EPOLLOUT |
938 EPOLLRDNORM |
939 EPOLLRDBAND);
940 sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
941 rcu_read_unlock();
942}
943
944/**
945 * af_alg_sendmsg - implementation of sendmsg system call handler
946 *
947 * The sendmsg system call handler obtains the user data and stores it
948 * in ctx->tsgl_list. This implies allocation of the required numbers of
949 * struct af_alg_tsgl.
950 *
951 * In addition, the ctx is filled with the information sent via CMSG.
952 *
953 * @sock: socket of connection to user space
954 * @msg: message from user space
955 * @size: size of message from user space
956 * @ivsize: the size of the IV for the cipher operation to verify that the
957 * user-space-provided IV has the right size
958 * Return: the number of copied data upon success, < 0 upon error
959 */
960int af_alg_sendmsg(struct socket *sock, struct msghdr *msg, size_t size,
961 unsigned int ivsize)
962{
963 struct sock *sk = sock->sk;
964 struct alg_sock *ask = alg_sk(sk);
965 struct af_alg_ctx *ctx = ask->private;
966 struct af_alg_tsgl *sgl;
967 struct af_alg_control con = {};
968 long copied = 0;
969 bool enc = false;
970 bool init = false;
971 int err = 0;
972
973 if (msg->msg_controllen) {
974 err = af_alg_cmsg_send(msg, &con);
975 if (err)
976 return err;
977
978 init = true;
979 switch (con.op) {
980 case ALG_OP_ENCRYPT:
981 enc = true;
982 break;
983 case ALG_OP_DECRYPT:
984 enc = false;
985 break;
986 default:
987 return -EINVAL;
988 }
989
990 if (con.iv && con.iv->ivlen != ivsize)
991 return -EINVAL;
992 }
993
994 lock_sock(sk);
995 if (ctx->init && !ctx->more) {
996 if (ctx->used) {
997 err = -EINVAL;
998 goto unlock;
999 }
1000
1001 pr_info_once(
1002 "%s sent an empty control message without MSG_MORE.\n",
1003 current->comm);
1004 }
1005 ctx->init = true;
1006
1007 if (init) {
1008 ctx->enc = enc;
1009 if (con.iv)
1010 memcpy(ctx->iv, con.iv->iv, ivsize);
1011
1012 ctx->aead_assoclen = con.aead_assoclen;
1013 }
1014
1015 while (size) {
1016 struct scatterlist *sg;
1017 size_t len = size;
1018 size_t plen;
1019
1020 /* use the existing memory in an allocated page */
1021 if (ctx->merge) {
1022 sgl = list_entry(ctx->tsgl_list.prev,
1023 struct af_alg_tsgl, list);
1024 sg = sgl->sg + sgl->cur - 1;
1025 len = min_t(size_t, len,
1026 PAGE_SIZE - sg->offset - sg->length);
1027
1028 err = memcpy_from_msg(page_address(sg_page(sg)) +
1029 sg->offset + sg->length,
1030 msg, len);
1031 if (err)
1032 goto unlock;
1033
1034 sg->length += len;
1035 ctx->merge = (sg->offset + sg->length) &
1036 (PAGE_SIZE - 1);
1037
1038 ctx->used += len;
1039 copied += len;
1040 size -= len;
1041 continue;
1042 }
1043
1044 if (!af_alg_writable(sk)) {
1045 err = af_alg_wait_for_wmem(sk, msg->msg_flags);
1046 if (err)
1047 goto unlock;
1048 }
1049
1050 /* allocate a new page */
1051 len = min_t(unsigned long, len, af_alg_sndbuf(sk));
1052
1053 err = af_alg_alloc_tsgl(sk);
1054 if (err)
1055 goto unlock;
1056
1057 sgl = list_entry(ctx->tsgl_list.prev, struct af_alg_tsgl,
1058 list);
1059 sg = sgl->sg;
1060 if (sgl->cur)
1061 sg_unmark_end(sg + sgl->cur - 1);
1062
1063 do {
1064 struct page *pg;
1065 unsigned int i = sgl->cur;
1066
1067 plen = min_t(size_t, len, PAGE_SIZE);
1068
1069 pg = alloc_page(GFP_KERNEL);
1070 if (!pg) {
1071 err = -ENOMEM;
1072 goto unlock;
1073 }
1074
1075 sg_assign_page(sg + i, pg);
1076
1077 err = memcpy_from_msg(page_address(sg_page(sg + i)),
1078 msg, plen);
1079 if (err) {
1080 __free_page(sg_page(sg + i));
1081 sg_assign_page(sg + i, NULL);
1082 goto unlock;
1083 }
1084
1085 sg[i].length = plen;
1086 len -= plen;
1087 ctx->used += plen;
1088 copied += plen;
1089 size -= plen;
1090 sgl->cur++;
1091 } while (len && sgl->cur < MAX_SGL_ENTS);
1092
1093 if (!size)
1094 sg_mark_end(sg + sgl->cur - 1);
1095
1096 ctx->merge = plen & (PAGE_SIZE - 1);
1097 }
1098
1099 err = 0;
1100
1101 ctx->more = msg->msg_flags & MSG_MORE;
1102
1103unlock:
1104 af_alg_data_wakeup(sk);
1105 release_sock(sk);
1106
1107 return copied ?: err;
1108}
1109EXPORT_SYMBOL_GPL(af_alg_sendmsg);
1110
1111/**
1112 * af_alg_sendpage - sendpage system call handler
1113 * @sock: socket of connection to user space to write to
1114 * @page: data to send
1115 * @offset: offset into page to begin sending
1116 * @size: length of data
1117 * @flags: message send/receive flags
1118 *
1119 * This is a generic implementation of sendpage to fill ctx->tsgl_list.
1120 */
1121ssize_t af_alg_sendpage(struct socket *sock, struct page *page,
1122 int offset, size_t size, int flags)
1123{
1124 struct sock *sk = sock->sk;
1125 struct alg_sock *ask = alg_sk(sk);
1126 struct af_alg_ctx *ctx = ask->private;
1127 struct af_alg_tsgl *sgl;
1128 int err = -EINVAL;
1129
1130 if (flags & MSG_SENDPAGE_NOTLAST)
1131 flags |= MSG_MORE;
1132
1133 lock_sock(sk);
1134 if (!ctx->more && ctx->used)
1135 goto unlock;
1136
1137 if (!size)
1138 goto done;
1139
1140 if (!af_alg_writable(sk)) {
1141 err = af_alg_wait_for_wmem(sk, flags);
1142 if (err)
1143 goto unlock;
1144 }
1145
1146 err = af_alg_alloc_tsgl(sk);
1147 if (err)
1148 goto unlock;
1149
1150 ctx->merge = 0;
1151 sgl = list_entry(ctx->tsgl_list.prev, struct af_alg_tsgl, list);
1152
1153 if (sgl->cur)
1154 sg_unmark_end(sgl->sg + sgl->cur - 1);
1155
1156 sg_mark_end(sgl->sg + sgl->cur);
1157
1158 get_page(page);
1159 sg_set_page(sgl->sg + sgl->cur, page, size, offset);
1160 sgl->cur++;
1161 ctx->used += size;
1162
1163done:
1164 ctx->more = flags & MSG_MORE;
1165
1166unlock:
1167 af_alg_data_wakeup(sk);
1168 release_sock(sk);
1169
1170 return err ?: size;
1171}
1172EXPORT_SYMBOL_GPL(af_alg_sendpage);
1173
1174/**
1175 * af_alg_free_resources - release resources required for crypto request
1176 * @areq: Request holding the TX and RX SGL
1177 */
1178void af_alg_free_resources(struct af_alg_async_req *areq)
1179{
1180 struct sock *sk = areq->sk;
1181
1182 af_alg_free_areq_sgls(areq);
1183 sock_kfree_s(sk, areq, areq->areqlen);
1184}
1185EXPORT_SYMBOL_GPL(af_alg_free_resources);
1186
1187/**
1188 * af_alg_async_cb - AIO callback handler
1189 * @_req: async request info
1190 * @err: if non-zero, error result to be returned via ki_complete();
1191 * otherwise return the AIO output length via ki_complete().
1192 *
1193 * This handler cleans up the struct af_alg_async_req upon completion of the
1194 * AIO operation.
1195 *
1196 * The number of bytes to be generated with the AIO operation must be set
1197 * in areq->outlen before the AIO callback handler is invoked.
1198 */
1199void af_alg_async_cb(struct crypto_async_request *_req, int err)
1200{
1201 struct af_alg_async_req *areq = _req->data;
1202 struct sock *sk = areq->sk;
1203 struct kiocb *iocb = areq->iocb;
1204 unsigned int resultlen;
1205
1206 /* Buffer size written by crypto operation. */
1207 resultlen = areq->outlen;
1208
1209 af_alg_free_resources(areq);
1210 sock_put(sk);
1211
1212 iocb->ki_complete(iocb, err ? err : (int)resultlen);
1213}
1214EXPORT_SYMBOL_GPL(af_alg_async_cb);
1215
1216/**
1217 * af_alg_poll - poll system call handler
1218 * @file: file pointer
1219 * @sock: socket to poll
1220 * @wait: poll_table
1221 */
1222__poll_t af_alg_poll(struct file *file, struct socket *sock,
1223 poll_table *wait)
1224{
1225 struct sock *sk = sock->sk;
1226 struct alg_sock *ask = alg_sk(sk);
1227 struct af_alg_ctx *ctx = ask->private;
1228 __poll_t mask;
1229
1230 sock_poll_wait(file, sock, wait);
1231 mask = 0;
1232
1233 if (!ctx->more || ctx->used)
1234 mask |= EPOLLIN | EPOLLRDNORM;
1235
1236 if (af_alg_writable(sk))
1237 mask |= EPOLLOUT | EPOLLWRNORM | EPOLLWRBAND;
1238
1239 return mask;
1240}
1241EXPORT_SYMBOL_GPL(af_alg_poll);
1242
1243/**
1244 * af_alg_alloc_areq - allocate struct af_alg_async_req
1245 *
1246 * @sk: socket of connection to user space
1247 * @areqlen: size of struct af_alg_async_req + crypto_*_reqsize
1248 * Return: allocated data structure or ERR_PTR upon error
1249 */
1250struct af_alg_async_req *af_alg_alloc_areq(struct sock *sk,
1251 unsigned int areqlen)
1252{
1253 struct af_alg_async_req *areq = sock_kmalloc(sk, areqlen, GFP_KERNEL);
1254
1255 if (unlikely(!areq))
1256 return ERR_PTR(-ENOMEM);
1257
1258 areq->areqlen = areqlen;
1259 areq->sk = sk;
1260 areq->last_rsgl = NULL;
1261 INIT_LIST_HEAD(&areq->rsgl_list);
1262 areq->tsgl = NULL;
1263 areq->tsgl_entries = 0;
1264
1265 return areq;
1266}
1267EXPORT_SYMBOL_GPL(af_alg_alloc_areq);
1268
1269/**
1270 * af_alg_get_rsgl - create the RX SGL for the output data from the crypto
1271 * operation
1272 *
1273 * @sk: socket of connection to user space
1274 * @msg: user space message
1275 * @flags: flags used to invoke recvmsg with
1276 * @areq: instance of the cryptographic request that will hold the RX SGL
1277 * @maxsize: maximum number of bytes to be pulled from user space
1278 * @outlen: number of bytes in the RX SGL
1279 * Return: 0 on success, < 0 upon error
1280 */
1281int af_alg_get_rsgl(struct sock *sk, struct msghdr *msg, int flags,
1282 struct af_alg_async_req *areq, size_t maxsize,
1283 size_t *outlen)
1284{
1285 struct alg_sock *ask = alg_sk(sk);
1286 struct af_alg_ctx *ctx = ask->private;
1287 size_t len = 0;
1288
1289 while (maxsize > len && msg_data_left(msg)) {
1290 struct af_alg_rsgl *rsgl;
1291 size_t seglen;
1292 int err;
1293
1294 /* limit the amount of readable buffers */
1295 if (!af_alg_readable(sk))
1296 break;
1297
1298 seglen = min_t(size_t, (maxsize - len),
1299 msg_data_left(msg));
1300
1301 if (list_empty(&areq->rsgl_list)) {
1302 rsgl = &areq->first_rsgl;
1303 } else {
1304 rsgl = sock_kmalloc(sk, sizeof(*rsgl), GFP_KERNEL);
1305 if (unlikely(!rsgl))
1306 return -ENOMEM;
1307 }
1308
1309 rsgl->sgl.npages = 0;
1310 list_add_tail(&rsgl->list, &areq->rsgl_list);
1311
1312 /* make one iovec available as scatterlist */
1313 err = af_alg_make_sg(&rsgl->sgl, &msg->msg_iter, seglen);
1314 if (err < 0) {
1315 rsgl->sg_num_bytes = 0;
1316 return err;
1317 }
1318
1319 /* chain the new scatterlist with previous one */
1320 if (areq->last_rsgl)
1321 af_alg_link_sg(&areq->last_rsgl->sgl, &rsgl->sgl);
1322
1323 areq->last_rsgl = rsgl;
1324 len += err;
1325 atomic_add(err, &ctx->rcvused);
1326 rsgl->sg_num_bytes = err;
1327 }
1328
1329 *outlen = len;
1330 return 0;
1331}
1332EXPORT_SYMBOL_GPL(af_alg_get_rsgl);
1333
1334static int __init af_alg_init(void)
1335{
1336 int err = proto_register(&alg_proto, 0);
1337
1338 if (err)
1339 goto out;
1340
1341 err = sock_register(&alg_family);
1342 if (err != 0)
1343 goto out_unregister_proto;
1344
1345out:
1346 return err;
1347
1348out_unregister_proto:
1349 proto_unregister(&alg_proto);
1350 goto out;
1351}
1352
1353static void __exit af_alg_exit(void)
1354{
1355 sock_unregister(PF_ALG);
1356 proto_unregister(&alg_proto);
1357}
1358
1359module_init(af_alg_init);
1360module_exit(af_alg_exit);
1361MODULE_LICENSE("GPL");
1362MODULE_ALIAS_NETPROTO(AF_ALG);