1 // SPDX-License-Identifier: GPL-2.0-or-later
3 * af_alg: User-space algorithm interface
5 * This file provides the user-space API for algorithms.
7 * Copyright (c) 2010 Herbert Xu <herbert@gondor.apana.org.au>
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>
23 struct alg_type_list
{
24 const struct af_alg_type
*type
;
25 struct list_head list
;
28 static struct proto alg_proto
= {
31 .obj_size
= sizeof(struct alg_sock
),
34 static LIST_HEAD(alg_types
);
35 static DECLARE_RWSEM(alg_types_sem
);
37 static const struct af_alg_type
*alg_get_type(const char *name
)
39 const struct af_alg_type
*type
= ERR_PTR(-ENOENT
);
40 struct alg_type_list
*node
;
42 down_read(&alg_types_sem
);
43 list_for_each_entry(node
, &alg_types
, list
) {
44 if (strcmp(node
->type
->name
, name
))
47 if (try_module_get(node
->type
->owner
))
51 up_read(&alg_types_sem
);
56 int af_alg_register_type(const struct af_alg_type
*type
)
58 struct alg_type_list
*node
;
61 down_write(&alg_types_sem
);
62 list_for_each_entry(node
, &alg_types
, list
) {
63 if (!strcmp(node
->type
->name
, type
->name
))
67 node
= kmalloc(sizeof(*node
), GFP_KERNEL
);
72 type
->ops
->owner
= THIS_MODULE
;
74 type
->ops_nokey
->owner
= THIS_MODULE
;
76 list_add(&node
->list
, &alg_types
);
80 up_write(&alg_types_sem
);
84 EXPORT_SYMBOL_GPL(af_alg_register_type
);
86 int af_alg_unregister_type(const struct af_alg_type
*type
)
88 struct alg_type_list
*node
;
91 down_write(&alg_types_sem
);
92 list_for_each_entry(node
, &alg_types
, list
) {
93 if (strcmp(node
->type
->name
, type
->name
))
96 list_del(&node
->list
);
101 up_write(&alg_types_sem
);
105 EXPORT_SYMBOL_GPL(af_alg_unregister_type
);
107 static void alg_do_release(const struct af_alg_type
*type
, void *private)
112 type
->release(private);
113 module_put(type
->owner
);
116 int af_alg_release(struct socket
*sock
)
124 EXPORT_SYMBOL_GPL(af_alg_release
);
126 void af_alg_release_parent(struct sock
*sk
)
128 struct alg_sock
*ask
= alg_sk(sk
);
129 unsigned int nokey
= atomic_read(&ask
->nokey_refcnt
);
135 atomic_dec(&ask
->nokey_refcnt
);
137 if (atomic_dec_and_test(&ask
->refcnt
))
140 EXPORT_SYMBOL_GPL(af_alg_release_parent
);
142 static int alg_bind(struct socket
*sock
, struct sockaddr
*uaddr
, int addr_len
)
144 const u32 allowed
= CRYPTO_ALG_KERN_DRIVER_ONLY
;
145 struct sock
*sk
= sock
->sk
;
146 struct alg_sock
*ask
= alg_sk(sk
);
147 struct sockaddr_alg_new
*sa
= (void *)uaddr
;
148 const struct af_alg_type
*type
;
152 if (sock
->state
== SS_CONNECTED
)
155 BUILD_BUG_ON(offsetof(struct sockaddr_alg_new
, salg_name
) !=
156 offsetof(struct sockaddr_alg
, salg_name
));
157 BUILD_BUG_ON(offsetof(struct sockaddr_alg
, salg_name
) != sizeof(*sa
));
159 if (addr_len
< sizeof(*sa
) + 1)
162 /* If caller uses non-allowed flag, return error. */
163 if ((sa
->salg_feat
& ~allowed
) || (sa
->salg_mask
& ~allowed
))
166 sa
->salg_type
[sizeof(sa
->salg_type
) - 1] = 0;
167 sa
->salg_name
[addr_len
- sizeof(*sa
) - 1] = 0;
169 type
= alg_get_type(sa
->salg_type
);
170 if (PTR_ERR(type
) == -ENOENT
) {
171 request_module("algif-%s", sa
->salg_type
);
172 type
= alg_get_type(sa
->salg_type
);
176 return PTR_ERR(type
);
178 private = type
->bind(sa
->salg_name
, sa
->salg_feat
, sa
->salg_mask
);
179 if (IS_ERR(private)) {
180 module_put(type
->owner
);
181 return PTR_ERR(private);
186 if (atomic_read(&ask
->refcnt
))
189 swap(ask
->type
, type
);
190 swap(ask
->private, private);
197 alg_do_release(type
, private);
202 static int alg_setkey(struct sock
*sk
, sockptr_t ukey
, unsigned int keylen
)
204 struct alg_sock
*ask
= alg_sk(sk
);
205 const struct af_alg_type
*type
= ask
->type
;
209 key
= sock_kmalloc(sk
, keylen
, GFP_KERNEL
);
214 if (copy_from_sockptr(key
, ukey
, keylen
))
217 err
= type
->setkey(ask
->private, key
, keylen
);
220 sock_kzfree_s(sk
, key
, keylen
);
225 static int alg_setsockopt(struct socket
*sock
, int level
, int optname
,
226 sockptr_t optval
, unsigned int optlen
)
228 struct sock
*sk
= sock
->sk
;
229 struct alg_sock
*ask
= alg_sk(sk
);
230 const struct af_alg_type
*type
;
234 if (atomic_read(&ask
->refcnt
) != atomic_read(&ask
->nokey_refcnt
))
240 if (level
!= SOL_ALG
|| !type
)
245 if (sock
->state
== SS_CONNECTED
)
250 err
= alg_setkey(sk
, optval
, optlen
);
252 case ALG_SET_AEAD_AUTHSIZE
:
253 if (sock
->state
== SS_CONNECTED
)
255 if (!type
->setauthsize
)
257 err
= type
->setauthsize(ask
->private, optlen
);
259 case ALG_SET_DRBG_ENTROPY
:
260 if (sock
->state
== SS_CONNECTED
)
262 if (!type
->setentropy
)
265 err
= type
->setentropy(ask
->private, optval
, optlen
);
274 int af_alg_accept(struct sock
*sk
, struct socket
*newsock
, bool kern
)
276 struct alg_sock
*ask
= alg_sk(sk
);
277 const struct af_alg_type
*type
;
289 sk2
= sk_alloc(sock_net(sk
), PF_ALG
, GFP_KERNEL
, &alg_proto
, kern
);
294 sock_init_data(newsock
, sk2
);
295 security_sock_graft(sk2
, newsock
);
296 security_sk_clone(sk
, sk2
);
299 * newsock->ops assigned here to allow type->accept call to override
300 * them when required.
302 newsock
->ops
= type
->ops
;
303 err
= type
->accept(ask
->private, sk2
);
305 nokey
= err
== -ENOKEY
;
306 if (nokey
&& type
->accept_nokey
)
307 err
= type
->accept_nokey(ask
->private, sk2
);
312 if (atomic_inc_return_relaxed(&ask
->refcnt
) == 1)
315 atomic_inc(&ask
->nokey_refcnt
);
316 atomic_set(&alg_sk(sk2
)->nokey_refcnt
, 1);
318 alg_sk(sk2
)->parent
= sk
;
319 alg_sk(sk2
)->type
= type
;
321 newsock
->state
= SS_CONNECTED
;
324 newsock
->ops
= type
->ops_nokey
;
333 EXPORT_SYMBOL_GPL(af_alg_accept
);
335 static int alg_accept(struct socket
*sock
, struct socket
*newsock
, int flags
,
338 return af_alg_accept(sock
->sk
, newsock
, kern
);
341 static const struct proto_ops alg_proto_ops
= {
343 .owner
= THIS_MODULE
,
345 .connect
= sock_no_connect
,
346 .socketpair
= sock_no_socketpair
,
347 .getname
= sock_no_getname
,
348 .ioctl
= sock_no_ioctl
,
349 .listen
= sock_no_listen
,
350 .shutdown
= sock_no_shutdown
,
351 .mmap
= sock_no_mmap
,
352 .sendpage
= sock_no_sendpage
,
353 .sendmsg
= sock_no_sendmsg
,
354 .recvmsg
= sock_no_recvmsg
,
357 .release
= af_alg_release
,
358 .setsockopt
= alg_setsockopt
,
359 .accept
= alg_accept
,
362 static void alg_sock_destruct(struct sock
*sk
)
364 struct alg_sock
*ask
= alg_sk(sk
);
366 alg_do_release(ask
->type
, ask
->private);
369 static int alg_create(struct net
*net
, struct socket
*sock
, int protocol
,
375 if (sock
->type
!= SOCK_SEQPACKET
)
376 return -ESOCKTNOSUPPORT
;
378 return -EPROTONOSUPPORT
;
381 sk
= sk_alloc(net
, PF_ALG
, GFP_KERNEL
, &alg_proto
, kern
);
385 sock
->ops
= &alg_proto_ops
;
386 sock_init_data(sock
, sk
);
388 sk
->sk_destruct
= alg_sock_destruct
;
395 static const struct net_proto_family alg_family
= {
397 .create
= alg_create
,
398 .owner
= THIS_MODULE
,
401 int af_alg_make_sg(struct af_alg_sgl
*sgl
, struct iov_iter
*iter
, int len
)
407 n
= iov_iter_get_pages2(iter
, sgl
->pages
, len
, ALG_MAX_PAGES
, &off
);
411 npages
= DIV_ROUND_UP(off
+ n
, PAGE_SIZE
);
412 if (WARN_ON(npages
== 0))
414 /* Add one extra for linking */
415 sg_init_table(sgl
->sg
, npages
+ 1);
417 for (i
= 0, len
= n
; i
< npages
; i
++) {
418 int plen
= min_t(int, len
, PAGE_SIZE
- off
);
420 sg_set_page(sgl
->sg
+ i
, sgl
->pages
[i
], plen
, off
);
425 sg_mark_end(sgl
->sg
+ npages
- 1);
426 sgl
->npages
= npages
;
430 EXPORT_SYMBOL_GPL(af_alg_make_sg
);
432 static void af_alg_link_sg(struct af_alg_sgl
*sgl_prev
,
433 struct af_alg_sgl
*sgl_new
)
435 sg_unmark_end(sgl_prev
->sg
+ sgl_prev
->npages
- 1);
436 sg_chain(sgl_prev
->sg
, sgl_prev
->npages
+ 1, sgl_new
->sg
);
439 void af_alg_free_sg(struct af_alg_sgl
*sgl
)
443 for (i
= 0; i
< sgl
->npages
; i
++)
444 put_page(sgl
->pages
[i
]);
446 EXPORT_SYMBOL_GPL(af_alg_free_sg
);
448 static int af_alg_cmsg_send(struct msghdr
*msg
, struct af_alg_control
*con
)
450 struct cmsghdr
*cmsg
;
452 for_each_cmsghdr(cmsg
, msg
) {
453 if (!CMSG_OK(msg
, cmsg
))
455 if (cmsg
->cmsg_level
!= SOL_ALG
)
458 switch (cmsg
->cmsg_type
) {
460 if (cmsg
->cmsg_len
< CMSG_LEN(sizeof(*con
->iv
)))
462 con
->iv
= (void *)CMSG_DATA(cmsg
);
463 if (cmsg
->cmsg_len
< CMSG_LEN(con
->iv
->ivlen
+
469 if (cmsg
->cmsg_len
< CMSG_LEN(sizeof(u32
)))
471 con
->op
= *(u32
*)CMSG_DATA(cmsg
);
474 case ALG_SET_AEAD_ASSOCLEN
:
475 if (cmsg
->cmsg_len
< CMSG_LEN(sizeof(u32
)))
477 con
->aead_assoclen
= *(u32
*)CMSG_DATA(cmsg
);
489 * af_alg_alloc_tsgl - allocate the TX SGL
491 * @sk: socket of connection to user space
492 * Return: 0 upon success, < 0 upon error
494 static int af_alg_alloc_tsgl(struct sock
*sk
)
496 struct alg_sock
*ask
= alg_sk(sk
);
497 struct af_alg_ctx
*ctx
= ask
->private;
498 struct af_alg_tsgl
*sgl
;
499 struct scatterlist
*sg
= NULL
;
501 sgl
= list_entry(ctx
->tsgl_list
.prev
, struct af_alg_tsgl
, list
);
502 if (!list_empty(&ctx
->tsgl_list
))
505 if (!sg
|| sgl
->cur
>= MAX_SGL_ENTS
) {
506 sgl
= sock_kmalloc(sk
,
507 struct_size(sgl
, sg
, (MAX_SGL_ENTS
+ 1)),
512 sg_init_table(sgl
->sg
, MAX_SGL_ENTS
+ 1);
516 sg_chain(sg
, MAX_SGL_ENTS
+ 1, sgl
->sg
);
518 list_add_tail(&sgl
->list
, &ctx
->tsgl_list
);
525 * af_alg_count_tsgl - Count number of TX SG entries
527 * The counting starts from the beginning of the SGL to @bytes. If
528 * an @offset is provided, the counting of the SG entries starts at the @offset.
530 * @sk: socket of connection to user space
531 * @bytes: Count the number of SG entries holding given number of bytes.
532 * @offset: Start the counting of SG entries from the given offset.
533 * Return: Number of TX SG entries found given the constraints
535 unsigned int af_alg_count_tsgl(struct sock
*sk
, size_t bytes
, size_t offset
)
537 const struct alg_sock
*ask
= alg_sk(sk
);
538 const struct af_alg_ctx
*ctx
= ask
->private;
539 const struct af_alg_tsgl
*sgl
;
541 unsigned int sgl_count
= 0;
546 list_for_each_entry(sgl
, &ctx
->tsgl_list
, list
) {
547 const struct scatterlist
*sg
= sgl
->sg
;
549 for (i
= 0; i
< sgl
->cur
; i
++) {
553 if (offset
>= sg
[i
].length
) {
554 offset
-= sg
[i
].length
;
555 bytes
-= sg
[i
].length
;
559 bytes_count
= sg
[i
].length
- offset
;
564 /* If we have seen requested number of bytes, stop */
565 if (bytes_count
>= bytes
)
568 bytes
-= bytes_count
;
574 EXPORT_SYMBOL_GPL(af_alg_count_tsgl
);
577 * af_alg_pull_tsgl - Release the specified buffers from TX SGL
579 * If @dst is non-null, reassign the pages to @dst. The caller must release
580 * the pages. If @dst_offset is given only reassign the pages to @dst starting
581 * at the @dst_offset (byte). The caller must ensure that @dst is large
582 * enough (e.g. by using af_alg_count_tsgl with the same offset).
584 * @sk: socket of connection to user space
585 * @used: Number of bytes to pull from TX SGL
586 * @dst: If non-NULL, buffer is reassigned to dst SGL instead of releasing. The
587 * caller must release the buffers in dst.
588 * @dst_offset: Reassign the TX SGL from given offset. All buffers before
589 * reaching the offset is released.
591 void af_alg_pull_tsgl(struct sock
*sk
, size_t used
, struct scatterlist
*dst
,
594 struct alg_sock
*ask
= alg_sk(sk
);
595 struct af_alg_ctx
*ctx
= ask
->private;
596 struct af_alg_tsgl
*sgl
;
597 struct scatterlist
*sg
;
598 unsigned int i
, j
= 0;
600 while (!list_empty(&ctx
->tsgl_list
)) {
601 sgl
= list_first_entry(&ctx
->tsgl_list
, struct af_alg_tsgl
,
605 for (i
= 0; i
< sgl
->cur
; i
++) {
606 size_t plen
= min_t(size_t, used
, sg
[i
].length
);
607 struct page
*page
= sg_page(sg
+ i
);
613 * Assumption: caller created af_alg_count_tsgl(len)
617 if (dst_offset
>= plen
) {
618 /* discard page before offset */
621 /* reassign page to dst after offset */
623 sg_set_page(dst
+ j
, page
,
625 sg
[i
].offset
+ dst_offset
);
631 sg
[i
].length
-= plen
;
632 sg
[i
].offset
+= plen
;
641 sg_assign_page(sg
+ i
, NULL
);
644 list_del(&sgl
->list
);
645 sock_kfree_s(sk
, sgl
, struct_size(sgl
, sg
, MAX_SGL_ENTS
+ 1));
650 ctx
->init
= ctx
->more
;
652 EXPORT_SYMBOL_GPL(af_alg_pull_tsgl
);
655 * af_alg_free_areq_sgls - Release TX and RX SGLs of the request
657 * @areq: Request holding the TX and RX SGL
659 static void af_alg_free_areq_sgls(struct af_alg_async_req
*areq
)
661 struct sock
*sk
= areq
->sk
;
662 struct alg_sock
*ask
= alg_sk(sk
);
663 struct af_alg_ctx
*ctx
= ask
->private;
664 struct af_alg_rsgl
*rsgl
, *tmp
;
665 struct scatterlist
*tsgl
;
666 struct scatterlist
*sg
;
669 list_for_each_entry_safe(rsgl
, tmp
, &areq
->rsgl_list
, list
) {
670 atomic_sub(rsgl
->sg_num_bytes
, &ctx
->rcvused
);
671 af_alg_free_sg(&rsgl
->sgl
);
672 list_del(&rsgl
->list
);
673 if (rsgl
!= &areq
->first_rsgl
)
674 sock_kfree_s(sk
, rsgl
, sizeof(*rsgl
));
679 for_each_sg(tsgl
, sg
, areq
->tsgl_entries
, i
) {
682 put_page(sg_page(sg
));
685 sock_kfree_s(sk
, tsgl
, areq
->tsgl_entries
* sizeof(*tsgl
));
690 * af_alg_wait_for_wmem - wait for availability of writable memory
692 * @sk: socket of connection to user space
693 * @flags: If MSG_DONTWAIT is set, then only report if function would sleep
694 * Return: 0 when writable memory is available, < 0 upon error
696 static int af_alg_wait_for_wmem(struct sock
*sk
, unsigned int flags
)
698 DEFINE_WAIT_FUNC(wait
, woken_wake_function
);
699 int err
= -ERESTARTSYS
;
702 if (flags
& MSG_DONTWAIT
)
705 sk_set_bit(SOCKWQ_ASYNC_NOSPACE
, sk
);
707 add_wait_queue(sk_sleep(sk
), &wait
);
709 if (signal_pending(current
))
711 timeout
= MAX_SCHEDULE_TIMEOUT
;
712 if (sk_wait_event(sk
, &timeout
, af_alg_writable(sk
), &wait
)) {
717 remove_wait_queue(sk_sleep(sk
), &wait
);
723 * af_alg_wmem_wakeup - wakeup caller when writable memory is available
725 * @sk: socket of connection to user space
727 void af_alg_wmem_wakeup(struct sock
*sk
)
729 struct socket_wq
*wq
;
731 if (!af_alg_writable(sk
))
735 wq
= rcu_dereference(sk
->sk_wq
);
736 if (skwq_has_sleeper(wq
))
737 wake_up_interruptible_sync_poll(&wq
->wait
, EPOLLIN
|
740 sk_wake_async(sk
, SOCK_WAKE_WAITD
, POLL_IN
);
743 EXPORT_SYMBOL_GPL(af_alg_wmem_wakeup
);
746 * af_alg_wait_for_data - wait for availability of TX data
748 * @sk: socket of connection to user space
749 * @flags: If MSG_DONTWAIT is set, then only report if function would sleep
750 * @min: Set to minimum request size if partial requests are allowed.
751 * Return: 0 when writable memory is available, < 0 upon error
753 int af_alg_wait_for_data(struct sock
*sk
, unsigned flags
, unsigned min
)
755 DEFINE_WAIT_FUNC(wait
, woken_wake_function
);
756 struct alg_sock
*ask
= alg_sk(sk
);
757 struct af_alg_ctx
*ctx
= ask
->private;
759 int err
= -ERESTARTSYS
;
761 if (flags
& MSG_DONTWAIT
)
764 sk_set_bit(SOCKWQ_ASYNC_WAITDATA
, sk
);
766 add_wait_queue(sk_sleep(sk
), &wait
);
768 if (signal_pending(current
))
770 timeout
= MAX_SCHEDULE_TIMEOUT
;
771 if (sk_wait_event(sk
, &timeout
,
772 ctx
->init
&& (!ctx
->more
||
773 (min
&& ctx
->used
>= min
)),
779 remove_wait_queue(sk_sleep(sk
), &wait
);
781 sk_clear_bit(SOCKWQ_ASYNC_WAITDATA
, sk
);
785 EXPORT_SYMBOL_GPL(af_alg_wait_for_data
);
788 * af_alg_data_wakeup - wakeup caller when new data can be sent to kernel
790 * @sk: socket of connection to user space
792 static void af_alg_data_wakeup(struct sock
*sk
)
794 struct alg_sock
*ask
= alg_sk(sk
);
795 struct af_alg_ctx
*ctx
= ask
->private;
796 struct socket_wq
*wq
;
802 wq
= rcu_dereference(sk
->sk_wq
);
803 if (skwq_has_sleeper(wq
))
804 wake_up_interruptible_sync_poll(&wq
->wait
, EPOLLOUT
|
807 sk_wake_async(sk
, SOCK_WAKE_SPACE
, POLL_OUT
);
812 * af_alg_sendmsg - implementation of sendmsg system call handler
814 * The sendmsg system call handler obtains the user data and stores it
815 * in ctx->tsgl_list. This implies allocation of the required numbers of
816 * struct af_alg_tsgl.
818 * In addition, the ctx is filled with the information sent via CMSG.
820 * @sock: socket of connection to user space
821 * @msg: message from user space
822 * @size: size of message from user space
823 * @ivsize: the size of the IV for the cipher operation to verify that the
824 * user-space-provided IV has the right size
825 * Return: the number of copied data upon success, < 0 upon error
827 int af_alg_sendmsg(struct socket
*sock
, struct msghdr
*msg
, size_t size
,
830 struct sock
*sk
= sock
->sk
;
831 struct alg_sock
*ask
= alg_sk(sk
);
832 struct af_alg_ctx
*ctx
= ask
->private;
833 struct af_alg_tsgl
*sgl
;
834 struct af_alg_control con
= {};
840 if (msg
->msg_controllen
) {
841 err
= af_alg_cmsg_send(msg
, &con
);
857 if (con
.iv
&& con
.iv
->ivlen
!= ivsize
)
862 if (ctx
->init
&& !ctx
->more
) {
869 "%s sent an empty control message without MSG_MORE.\n",
877 memcpy(ctx
->iv
, con
.iv
->iv
, ivsize
);
879 ctx
->aead_assoclen
= con
.aead_assoclen
;
883 struct scatterlist
*sg
;
887 /* use the existing memory in an allocated page */
889 sgl
= list_entry(ctx
->tsgl_list
.prev
,
890 struct af_alg_tsgl
, list
);
891 sg
= sgl
->sg
+ sgl
->cur
- 1;
892 len
= min_t(size_t, len
,
893 PAGE_SIZE
- sg
->offset
- sg
->length
);
895 err
= memcpy_from_msg(page_address(sg_page(sg
)) +
896 sg
->offset
+ sg
->length
,
902 ctx
->merge
= (sg
->offset
+ sg
->length
) &
911 if (!af_alg_writable(sk
)) {
912 err
= af_alg_wait_for_wmem(sk
, msg
->msg_flags
);
917 /* allocate a new page */
918 len
= min_t(unsigned long, len
, af_alg_sndbuf(sk
));
920 err
= af_alg_alloc_tsgl(sk
);
924 sgl
= list_entry(ctx
->tsgl_list
.prev
, struct af_alg_tsgl
,
928 sg_unmark_end(sg
+ sgl
->cur
- 1);
932 unsigned int i
= sgl
->cur
;
934 plen
= min_t(size_t, len
, PAGE_SIZE
);
936 pg
= alloc_page(GFP_KERNEL
);
942 sg_assign_page(sg
+ i
, pg
);
944 err
= memcpy_from_msg(page_address(sg_page(sg
+ i
)),
947 __free_page(sg_page(sg
+ i
));
948 sg_assign_page(sg
+ i
, NULL
);
958 } while (len
&& sgl
->cur
< MAX_SGL_ENTS
);
961 sg_mark_end(sg
+ sgl
->cur
- 1);
963 ctx
->merge
= plen
& (PAGE_SIZE
- 1);
968 ctx
->more
= msg
->msg_flags
& MSG_MORE
;
971 af_alg_data_wakeup(sk
);
974 return copied
?: err
;
976 EXPORT_SYMBOL_GPL(af_alg_sendmsg
);
979 * af_alg_sendpage - sendpage system call handler
980 * @sock: socket of connection to user space to write to
981 * @page: data to send
982 * @offset: offset into page to begin sending
983 * @size: length of data
984 * @flags: message send/receive flags
986 * This is a generic implementation of sendpage to fill ctx->tsgl_list.
988 ssize_t
af_alg_sendpage(struct socket
*sock
, struct page
*page
,
989 int offset
, size_t size
, int flags
)
991 struct sock
*sk
= sock
->sk
;
992 struct alg_sock
*ask
= alg_sk(sk
);
993 struct af_alg_ctx
*ctx
= ask
->private;
994 struct af_alg_tsgl
*sgl
;
997 if (flags
& MSG_SENDPAGE_NOTLAST
)
1001 if (!ctx
->more
&& ctx
->used
)
1007 if (!af_alg_writable(sk
)) {
1008 err
= af_alg_wait_for_wmem(sk
, flags
);
1013 err
= af_alg_alloc_tsgl(sk
);
1018 sgl
= list_entry(ctx
->tsgl_list
.prev
, struct af_alg_tsgl
, list
);
1021 sg_unmark_end(sgl
->sg
+ sgl
->cur
- 1);
1023 sg_mark_end(sgl
->sg
+ sgl
->cur
);
1026 sg_set_page(sgl
->sg
+ sgl
->cur
, page
, size
, offset
);
1031 ctx
->more
= flags
& MSG_MORE
;
1034 af_alg_data_wakeup(sk
);
1039 EXPORT_SYMBOL_GPL(af_alg_sendpage
);
1042 * af_alg_free_resources - release resources required for crypto request
1043 * @areq: Request holding the TX and RX SGL
1045 void af_alg_free_resources(struct af_alg_async_req
*areq
)
1047 struct sock
*sk
= areq
->sk
;
1049 af_alg_free_areq_sgls(areq
);
1050 sock_kfree_s(sk
, areq
, areq
->areqlen
);
1052 EXPORT_SYMBOL_GPL(af_alg_free_resources
);
1055 * af_alg_async_cb - AIO callback handler
1056 * @_req: async request info
1057 * @err: if non-zero, error result to be returned via ki_complete();
1058 * otherwise return the AIO output length via ki_complete().
1060 * This handler cleans up the struct af_alg_async_req upon completion of the
1063 * The number of bytes to be generated with the AIO operation must be set
1064 * in areq->outlen before the AIO callback handler is invoked.
1066 void af_alg_async_cb(struct crypto_async_request
*_req
, int err
)
1068 struct af_alg_async_req
*areq
= _req
->data
;
1069 struct sock
*sk
= areq
->sk
;
1070 struct kiocb
*iocb
= areq
->iocb
;
1071 unsigned int resultlen
;
1073 /* Buffer size written by crypto operation. */
1074 resultlen
= areq
->outlen
;
1076 af_alg_free_resources(areq
);
1079 iocb
->ki_complete(iocb
, err
? err
: (int)resultlen
);
1081 EXPORT_SYMBOL_GPL(af_alg_async_cb
);
1084 * af_alg_poll - poll system call handler
1085 * @file: file pointer
1086 * @sock: socket to poll
1089 __poll_t
af_alg_poll(struct file
*file
, struct socket
*sock
,
1092 struct sock
*sk
= sock
->sk
;
1093 struct alg_sock
*ask
= alg_sk(sk
);
1094 struct af_alg_ctx
*ctx
= ask
->private;
1097 sock_poll_wait(file
, sock
, wait
);
1100 if (!ctx
->more
|| ctx
->used
)
1101 mask
|= EPOLLIN
| EPOLLRDNORM
;
1103 if (af_alg_writable(sk
))
1104 mask
|= EPOLLOUT
| EPOLLWRNORM
| EPOLLWRBAND
;
1108 EXPORT_SYMBOL_GPL(af_alg_poll
);
1111 * af_alg_alloc_areq - allocate struct af_alg_async_req
1113 * @sk: socket of connection to user space
1114 * @areqlen: size of struct af_alg_async_req + crypto_*_reqsize
1115 * Return: allocated data structure or ERR_PTR upon error
1117 struct af_alg_async_req
*af_alg_alloc_areq(struct sock
*sk
,
1118 unsigned int areqlen
)
1120 struct af_alg_async_req
*areq
= sock_kmalloc(sk
, areqlen
, GFP_KERNEL
);
1122 if (unlikely(!areq
))
1123 return ERR_PTR(-ENOMEM
);
1125 areq
->areqlen
= areqlen
;
1127 areq
->last_rsgl
= NULL
;
1128 INIT_LIST_HEAD(&areq
->rsgl_list
);
1130 areq
->tsgl_entries
= 0;
1134 EXPORT_SYMBOL_GPL(af_alg_alloc_areq
);
1137 * af_alg_get_rsgl - create the RX SGL for the output data from the crypto
1140 * @sk: socket of connection to user space
1141 * @msg: user space message
1142 * @flags: flags used to invoke recvmsg with
1143 * @areq: instance of the cryptographic request that will hold the RX SGL
1144 * @maxsize: maximum number of bytes to be pulled from user space
1145 * @outlen: number of bytes in the RX SGL
1146 * Return: 0 on success, < 0 upon error
1148 int af_alg_get_rsgl(struct sock
*sk
, struct msghdr
*msg
, int flags
,
1149 struct af_alg_async_req
*areq
, size_t maxsize
,
1152 struct alg_sock
*ask
= alg_sk(sk
);
1153 struct af_alg_ctx
*ctx
= ask
->private;
1156 while (maxsize
> len
&& msg_data_left(msg
)) {
1157 struct af_alg_rsgl
*rsgl
;
1161 /* limit the amount of readable buffers */
1162 if (!af_alg_readable(sk
))
1165 seglen
= min_t(size_t, (maxsize
- len
),
1166 msg_data_left(msg
));
1168 if (list_empty(&areq
->rsgl_list
)) {
1169 rsgl
= &areq
->first_rsgl
;
1171 rsgl
= sock_kmalloc(sk
, sizeof(*rsgl
), GFP_KERNEL
);
1172 if (unlikely(!rsgl
))
1176 rsgl
->sgl
.npages
= 0;
1177 list_add_tail(&rsgl
->list
, &areq
->rsgl_list
);
1179 /* make one iovec available as scatterlist */
1180 err
= af_alg_make_sg(&rsgl
->sgl
, &msg
->msg_iter
, seglen
);
1182 rsgl
->sg_num_bytes
= 0;
1186 /* chain the new scatterlist with previous one */
1187 if (areq
->last_rsgl
)
1188 af_alg_link_sg(&areq
->last_rsgl
->sgl
, &rsgl
->sgl
);
1190 areq
->last_rsgl
= rsgl
;
1192 atomic_add(err
, &ctx
->rcvused
);
1193 rsgl
->sg_num_bytes
= err
;
1199 EXPORT_SYMBOL_GPL(af_alg_get_rsgl
);
1201 static int __init
af_alg_init(void)
1203 int err
= proto_register(&alg_proto
, 0);
1208 err
= sock_register(&alg_family
);
1210 goto out_unregister_proto
;
1215 out_unregister_proto
:
1216 proto_unregister(&alg_proto
);
1220 static void __exit
af_alg_exit(void)
1222 sock_unregister(PF_ALG
);
1223 proto_unregister(&alg_proto
);
1226 module_init(af_alg_init
);
1227 module_exit(af_alg_exit
);
1228 MODULE_LICENSE("GPL");
1229 MODULE_ALIAS_NETPROTO(AF_ALG
);