2 * af_alg: User-space algorithm interface
4 * This file provides the user-space API for algorithms.
6 * Copyright (c) 2010 Herbert Xu <herbert@gondor.apana.org.au>
8 * This program is free software; you can redistribute it and/or modify it
9 * under the terms of the GNU General Public License as published by the Free
10 * Software Foundation; either version 2 of the License, or (at your option)
15 #include <linux/atomic.h>
16 #include <crypto/if_alg.h>
17 #include <linux/crypto.h>
18 #include <linux/init.h>
19 #include <linux/kernel.h>
20 #include <linux/list.h>
21 #include <linux/module.h>
22 #include <linux/net.h>
23 #include <linux/rwsem.h>
24 #include <linux/sched/signal.h>
25 #include <linux/security.h>
27 struct alg_type_list {
28 const struct af_alg_type *type;
29 struct list_head list;
32 static atomic_long_t alg_memory_allocated;
34 static struct proto alg_proto = {
37 .memory_allocated = &alg_memory_allocated,
38 .obj_size = sizeof(struct alg_sock),
41 static LIST_HEAD(alg_types);
42 static DECLARE_RWSEM(alg_types_sem);
44 static const struct af_alg_type *alg_get_type(const char *name)
46 const struct af_alg_type *type = ERR_PTR(-ENOENT);
47 struct alg_type_list *node;
49 down_read(&alg_types_sem);
50 list_for_each_entry(node, &alg_types, list) {
51 if (strcmp(node->type->name, name))
54 if (try_module_get(node->type->owner))
58 up_read(&alg_types_sem);
63 int af_alg_register_type(const struct af_alg_type *type)
65 struct alg_type_list *node;
68 down_write(&alg_types_sem);
69 list_for_each_entry(node, &alg_types, list) {
70 if (!strcmp(node->type->name, type->name))
74 node = kmalloc(sizeof(*node), GFP_KERNEL);
79 type->ops->owner = THIS_MODULE;
81 type->ops_nokey->owner = THIS_MODULE;
83 list_add(&node->list, &alg_types);
87 up_write(&alg_types_sem);
91 EXPORT_SYMBOL_GPL(af_alg_register_type);
93 int af_alg_unregister_type(const struct af_alg_type *type)
95 struct alg_type_list *node;
98 down_write(&alg_types_sem);
99 list_for_each_entry(node, &alg_types, list) {
100 if (strcmp(node->type->name, type->name))
103 list_del(&node->list);
108 up_write(&alg_types_sem);
112 EXPORT_SYMBOL_GPL(af_alg_unregister_type);
114 static void alg_do_release(const struct af_alg_type *type, void *private)
119 type->release(private);
120 module_put(type->owner);
123 int af_alg_release(struct socket *sock)
131 EXPORT_SYMBOL_GPL(af_alg_release);
133 void af_alg_release_parent(struct sock *sk)
135 struct alg_sock *ask = alg_sk(sk);
136 unsigned int nokey = atomic_read(&ask->nokey_refcnt);
142 atomic_dec(&ask->nokey_refcnt);
144 if (atomic_dec_and_test(&ask->refcnt))
147 EXPORT_SYMBOL_GPL(af_alg_release_parent);
149 static int alg_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
151 const u32 allowed = CRYPTO_ALG_KERN_DRIVER_ONLY;
152 struct sock *sk = sock->sk;
153 struct alg_sock *ask = alg_sk(sk);
154 struct sockaddr_alg_new *sa = (void *)uaddr;
155 const struct af_alg_type *type;
159 if (sock->state == SS_CONNECTED)
162 BUILD_BUG_ON(offsetof(struct sockaddr_alg_new, salg_name) !=
163 offsetof(struct sockaddr_alg, salg_name));
164 BUILD_BUG_ON(offsetof(struct sockaddr_alg, salg_name) != sizeof(*sa));
166 if (addr_len < sizeof(*sa) + 1)
169 /* If caller uses non-allowed flag, return error. */
170 if ((sa->salg_feat & ~allowed) || (sa->salg_mask & ~allowed))
173 sa->salg_type[sizeof(sa->salg_type) - 1] = 0;
174 sa->salg_name[addr_len - sizeof(*sa) - 1] = 0;
176 type = alg_get_type(sa->salg_type);
177 if (IS_ERR(type) && PTR_ERR(type) == -ENOENT) {
178 request_module("algif-%s", sa->salg_type);
179 type = alg_get_type(sa->salg_type);
183 return PTR_ERR(type);
185 private = type->bind(sa->salg_name, sa->salg_feat, sa->salg_mask);
186 if (IS_ERR(private)) {
187 module_put(type->owner);
188 return PTR_ERR(private);
193 if (atomic_read(&ask->refcnt))
196 swap(ask->type, type);
197 swap(ask->private, private);
204 alg_do_release(type, private);
209 static int alg_setkey(struct sock *sk, char __user *ukey,
212 struct alg_sock *ask = alg_sk(sk);
213 const struct af_alg_type *type = ask->type;
217 key = sock_kmalloc(sk, keylen, GFP_KERNEL);
222 if (copy_from_user(key, ukey, keylen))
225 err = type->setkey(ask->private, key, keylen);
228 sock_kzfree_s(sk, key, keylen);
233 static int alg_setsockopt(struct socket *sock, int level, int optname,
234 char __user *optval, unsigned int optlen)
236 struct sock *sk = sock->sk;
237 struct alg_sock *ask = alg_sk(sk);
238 const struct af_alg_type *type;
242 if (atomic_read(&ask->refcnt) != atomic_read(&ask->nokey_refcnt))
248 if (level != SOL_ALG || !type)
253 if (sock->state == SS_CONNECTED)
258 err = alg_setkey(sk, optval, optlen);
260 case ALG_SET_AEAD_AUTHSIZE:
261 if (sock->state == SS_CONNECTED)
263 if (!type->setauthsize)
265 err = type->setauthsize(ask->private, 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);
298 err = type->accept(ask->private, sk2);
300 nokey = err == -ENOKEY;
301 if (nokey && type->accept_nokey)
302 err = type->accept_nokey(ask->private, sk2);
307 sk2->sk_family = PF_ALG;
309 if (atomic_inc_return_relaxed(&ask->refcnt) == 1)
312 atomic_inc(&ask->nokey_refcnt);
313 atomic_set(&alg_sk(sk2)->nokey_refcnt, 1);
315 alg_sk(sk2)->parent = sk;
316 alg_sk(sk2)->type = type;
318 newsock->ops = type->ops;
319 newsock->state = SS_CONNECTED;
322 newsock->ops = type->ops_nokey;
331 EXPORT_SYMBOL_GPL(af_alg_accept);
333 static int alg_accept(struct socket *sock, struct socket *newsock, int flags,
336 return af_alg_accept(sock->sk, newsock, kern);
339 static const struct proto_ops alg_proto_ops = {
341 .owner = THIS_MODULE,
343 .connect = sock_no_connect,
344 .socketpair = sock_no_socketpair,
345 .getname = sock_no_getname,
346 .ioctl = sock_no_ioctl,
347 .listen = sock_no_listen,
348 .shutdown = sock_no_shutdown,
349 .getsockopt = sock_no_getsockopt,
350 .mmap = sock_no_mmap,
351 .sendpage = sock_no_sendpage,
352 .sendmsg = sock_no_sendmsg,
353 .recvmsg = sock_no_recvmsg,
354 .poll = sock_no_poll,
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_family = PF_ALG;
389 sk->sk_destruct = alg_sock_destruct;
396 static const struct net_proto_family alg_family = {
398 .create = alg_create,
399 .owner = THIS_MODULE,
402 int af_alg_make_sg(struct af_alg_sgl *sgl, struct iov_iter *iter, int len)
408 n = iov_iter_get_pages(iter, sgl->pages, len, ALG_MAX_PAGES, &off);
412 npages = (off + n + PAGE_SIZE - 1) >> PAGE_SHIFT;
413 if (WARN_ON(npages == 0))
415 /* Add one extra for linking */
416 sg_init_table(sgl->sg, npages + 1);
418 for (i = 0, len = n; i < npages; i++) {
419 int plen = min_t(int, len, PAGE_SIZE - off);
421 sg_set_page(sgl->sg + i, sgl->pages[i], plen, off);
426 sg_mark_end(sgl->sg + npages - 1);
427 sgl->npages = npages;
431 EXPORT_SYMBOL_GPL(af_alg_make_sg);
433 void af_alg_link_sg(struct af_alg_sgl *sgl_prev, 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);
438 EXPORT_SYMBOL_GPL(af_alg_link_sg);
440 void af_alg_free_sg(struct af_alg_sgl *sgl)
444 for (i = 0; i < sgl->npages; i++)
445 put_page(sgl->pages[i]);
447 EXPORT_SYMBOL_GPL(af_alg_free_sg);
449 int af_alg_cmsg_send(struct msghdr *msg, struct af_alg_control *con)
451 struct cmsghdr *cmsg;
453 for_each_cmsghdr(cmsg, msg) {
454 if (!CMSG_OK(msg, cmsg))
456 if (cmsg->cmsg_level != SOL_ALG)
459 switch (cmsg->cmsg_type) {
461 if (cmsg->cmsg_len < CMSG_LEN(sizeof(*con->iv)))
463 con->iv = (void *)CMSG_DATA(cmsg);
464 if (cmsg->cmsg_len < CMSG_LEN(con->iv->ivlen +
470 if (cmsg->cmsg_len < CMSG_LEN(sizeof(u32)))
472 con->op = *(u32 *)CMSG_DATA(cmsg);
475 case ALG_SET_AEAD_ASSOCLEN:
476 if (cmsg->cmsg_len < CMSG_LEN(sizeof(u32)))
478 con->aead_assoclen = *(u32 *)CMSG_DATA(cmsg);
488 EXPORT_SYMBOL_GPL(af_alg_cmsg_send);
490 int af_alg_wait_for_completion(int err, struct af_alg_completion *completion)
495 wait_for_completion(&completion->completion);
496 reinit_completion(&completion->completion);
497 err = completion->err;
503 EXPORT_SYMBOL_GPL(af_alg_wait_for_completion);
505 void af_alg_complete(struct crypto_async_request *req, int err)
507 struct af_alg_completion *completion = req->data;
509 if (err == -EINPROGRESS)
512 completion->err = err;
513 complete(&completion->completion);
515 EXPORT_SYMBOL_GPL(af_alg_complete);
518 * af_alg_alloc_tsgl - allocate the TX SGL
520 * @sk socket of connection to user space
521 * @return: 0 upon success, < 0 upon error
523 int af_alg_alloc_tsgl(struct sock *sk)
525 struct alg_sock *ask = alg_sk(sk);
526 struct af_alg_ctx *ctx = ask->private;
527 struct af_alg_tsgl *sgl;
528 struct scatterlist *sg = NULL;
530 sgl = list_entry(ctx->tsgl_list.prev, struct af_alg_tsgl, list);
531 if (!list_empty(&ctx->tsgl_list))
534 if (!sg || sgl->cur >= MAX_SGL_ENTS) {
535 sgl = sock_kmalloc(sk, sizeof(*sgl) +
536 sizeof(sgl->sg[0]) * (MAX_SGL_ENTS + 1),
541 sg_init_table(sgl->sg, MAX_SGL_ENTS + 1);
545 sg_chain(sg, MAX_SGL_ENTS + 1, sgl->sg);
547 list_add_tail(&sgl->list, &ctx->tsgl_list);
552 EXPORT_SYMBOL_GPL(af_alg_alloc_tsgl);
555 * aead_count_tsgl - Count number of TX SG entries
557 * The counting starts from the beginning of the SGL to @bytes. If
558 * an offset is provided, the counting of the SG entries starts at the offset.
560 * @sk socket of connection to user space
561 * @bytes Count the number of SG entries holding given number of bytes.
562 * @offset Start the counting of SG entries from the given offset.
563 * @return Number of TX SG entries found given the constraints
565 unsigned int af_alg_count_tsgl(struct sock *sk, size_t bytes, size_t offset)
567 struct alg_sock *ask = alg_sk(sk);
568 struct af_alg_ctx *ctx = ask->private;
569 struct af_alg_tsgl *sgl, *tmp;
571 unsigned int sgl_count = 0;
576 list_for_each_entry_safe(sgl, tmp, &ctx->tsgl_list, list) {
577 struct scatterlist *sg = sgl->sg;
579 for (i = 0; i < sgl->cur; i++) {
583 if (offset >= sg[i].length) {
584 offset -= sg[i].length;
585 bytes -= sg[i].length;
589 bytes_count = sg[i].length - offset;
594 /* If we have seen requested number of bytes, stop */
595 if (bytes_count >= bytes)
598 bytes -= bytes_count;
604 EXPORT_SYMBOL_GPL(af_alg_count_tsgl);
607 * aead_pull_tsgl - Release the specified buffers from TX SGL
609 * If @dst is non-null, reassign the pages to dst. The caller must release
610 * the pages. If @dst_offset is given only reassign the pages to @dst starting
611 * at the @dst_offset (byte). The caller must ensure that @dst is large
612 * enough (e.g. by using af_alg_count_tsgl with the same offset).
614 * @sk socket of connection to user space
615 * @used Number of bytes to pull from TX SGL
616 * @dst If non-NULL, buffer is reassigned to dst SGL instead of releasing. The
617 * caller must release the buffers in dst.
618 * @dst_offset Reassign the TX SGL from given offset. All buffers before
619 * reaching the offset is released.
621 void af_alg_pull_tsgl(struct sock *sk, size_t used, struct scatterlist *dst,
624 struct alg_sock *ask = alg_sk(sk);
625 struct af_alg_ctx *ctx = ask->private;
626 struct af_alg_tsgl *sgl;
627 struct scatterlist *sg;
628 unsigned int i, j = 0;
630 while (!list_empty(&ctx->tsgl_list)) {
631 sgl = list_first_entry(&ctx->tsgl_list, struct af_alg_tsgl,
635 for (i = 0; i < sgl->cur; i++) {
636 size_t plen = min_t(size_t, used, sg[i].length);
637 struct page *page = sg_page(sg + i);
643 * Assumption: caller created af_alg_count_tsgl(len)
647 if (dst_offset >= plen) {
648 /* discard page before offset */
651 /* reassign page to dst after offset */
653 sg_set_page(dst + j, page,
655 sg[i].offset + dst_offset);
661 sg[i].length -= plen;
662 sg[i].offset += plen;
671 sg_assign_page(sg + i, NULL);
674 list_del(&sgl->list);
675 sock_kfree_s(sk, sgl, sizeof(*sgl) + sizeof(sgl->sg[0]) *
682 EXPORT_SYMBOL_GPL(af_alg_pull_tsgl);
685 * af_alg_free_areq_sgls - Release TX and RX SGLs of the request
687 * @areq Request holding the TX and RX SGL
689 void af_alg_free_areq_sgls(struct af_alg_async_req *areq)
691 struct sock *sk = areq->sk;
692 struct alg_sock *ask = alg_sk(sk);
693 struct af_alg_ctx *ctx = ask->private;
694 struct af_alg_rsgl *rsgl, *tmp;
695 struct scatterlist *tsgl;
696 struct scatterlist *sg;
699 list_for_each_entry_safe(rsgl, tmp, &areq->rsgl_list, list) {
700 atomic_sub(rsgl->sg_num_bytes, &ctx->rcvused);
701 af_alg_free_sg(&rsgl->sgl);
702 list_del(&rsgl->list);
703 if (rsgl != &areq->first_rsgl)
704 sock_kfree_s(sk, rsgl, sizeof(*rsgl));
709 for_each_sg(tsgl, sg, areq->tsgl_entries, i) {
712 put_page(sg_page(sg));
715 sock_kfree_s(sk, tsgl, areq->tsgl_entries * sizeof(*tsgl));
718 EXPORT_SYMBOL_GPL(af_alg_free_areq_sgls);
721 * af_alg_wait_for_wmem - wait for availability of writable memory
723 * @sk socket of connection to user space
724 * @flags If MSG_DONTWAIT is set, then only report if function would sleep
725 * @return 0 when writable memory is available, < 0 upon error
727 int af_alg_wait_for_wmem(struct sock *sk, unsigned int flags)
729 DEFINE_WAIT_FUNC(wait, woken_wake_function);
730 int err = -ERESTARTSYS;
733 if (flags & MSG_DONTWAIT)
736 sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
738 add_wait_queue(sk_sleep(sk), &wait);
740 if (signal_pending(current))
742 timeout = MAX_SCHEDULE_TIMEOUT;
743 if (sk_wait_event(sk, &timeout, af_alg_writable(sk), &wait)) {
748 remove_wait_queue(sk_sleep(sk), &wait);
752 EXPORT_SYMBOL_GPL(af_alg_wait_for_wmem);
755 * af_alg_wmem_wakeup - wakeup caller when writable memory is available
757 * @sk socket of connection to user space
759 void af_alg_wmem_wakeup(struct sock *sk)
761 struct socket_wq *wq;
763 if (!af_alg_writable(sk))
767 wq = rcu_dereference(sk->sk_wq);
768 if (skwq_has_sleeper(wq))
769 wake_up_interruptible_sync_poll(&wq->wait, POLLIN |
772 sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN);
775 EXPORT_SYMBOL_GPL(af_alg_wmem_wakeup);
778 * af_alg_wait_for_data - wait for availability of TX data
780 * @sk socket of connection to user space
781 * @flags If MSG_DONTWAIT is set, then only report if function would sleep
782 * @return 0 when writable memory is available, < 0 upon error
784 int af_alg_wait_for_data(struct sock *sk, unsigned flags)
786 DEFINE_WAIT_FUNC(wait, woken_wake_function);
787 struct alg_sock *ask = alg_sk(sk);
788 struct af_alg_ctx *ctx = ask->private;
790 int err = -ERESTARTSYS;
792 if (flags & MSG_DONTWAIT)
795 sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk);
797 add_wait_queue(sk_sleep(sk), &wait);
799 if (signal_pending(current))
801 timeout = MAX_SCHEDULE_TIMEOUT;
802 if (sk_wait_event(sk, &timeout, (ctx->used || !ctx->more),
808 remove_wait_queue(sk_sleep(sk), &wait);
810 sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk);
814 EXPORT_SYMBOL_GPL(af_alg_wait_for_data);
817 * af_alg_data_wakeup - wakeup caller when new data can be sent to kernel
819 * @sk socket of connection to user space
822 void af_alg_data_wakeup(struct sock *sk)
824 struct alg_sock *ask = alg_sk(sk);
825 struct af_alg_ctx *ctx = ask->private;
826 struct socket_wq *wq;
832 wq = rcu_dereference(sk->sk_wq);
833 if (skwq_has_sleeper(wq))
834 wake_up_interruptible_sync_poll(&wq->wait, POLLOUT |
837 sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
840 EXPORT_SYMBOL_GPL(af_alg_data_wakeup);
843 * af_alg_sendmsg - implementation of sendmsg system call handler
845 * The sendmsg system call handler obtains the user data and stores it
846 * in ctx->tsgl_list. This implies allocation of the required numbers of
847 * struct af_alg_tsgl.
849 * In addition, the ctx is filled with the information sent via CMSG.
851 * @sock socket of connection to user space
852 * @msg message from user space
853 * @size size of message from user space
854 * @ivsize the size of the IV for the cipher operation to verify that the
855 * user-space-provided IV has the right size
856 * @return the number of copied data upon success, < 0 upon error
858 int af_alg_sendmsg(struct socket *sock, struct msghdr *msg, size_t size,
861 struct sock *sk = sock->sk;
862 struct alg_sock *ask = alg_sk(sk);
863 struct af_alg_ctx *ctx = ask->private;
864 struct af_alg_tsgl *sgl;
865 struct af_alg_control con = {};
871 if (msg->msg_controllen) {
872 err = af_alg_cmsg_send(msg, &con);
888 if (con.iv && con.iv->ivlen != ivsize)
893 if (!ctx->more && ctx->used) {
901 memcpy(ctx->iv, con.iv->iv, ivsize);
903 ctx->aead_assoclen = con.aead_assoclen;
907 struct scatterlist *sg;
911 /* use the existing memory in an allocated page */
913 sgl = list_entry(ctx->tsgl_list.prev,
914 struct af_alg_tsgl, list);
915 sg = sgl->sg + sgl->cur - 1;
916 len = min_t(size_t, len,
917 PAGE_SIZE - sg->offset - sg->length);
919 err = memcpy_from_msg(page_address(sg_page(sg)) +
920 sg->offset + sg->length,
926 ctx->merge = (sg->offset + sg->length) &
935 if (!af_alg_writable(sk)) {
936 err = af_alg_wait_for_wmem(sk, msg->msg_flags);
941 /* allocate a new page */
942 len = min_t(unsigned long, len, af_alg_sndbuf(sk));
944 err = af_alg_alloc_tsgl(sk);
948 sgl = list_entry(ctx->tsgl_list.prev, struct af_alg_tsgl,
952 sg_unmark_end(sg + sgl->cur - 1);
955 unsigned int i = sgl->cur;
957 plen = min_t(size_t, len, PAGE_SIZE);
959 sg_assign_page(sg + i, alloc_page(GFP_KERNEL));
960 if (!sg_page(sg + i)) {
965 err = memcpy_from_msg(page_address(sg_page(sg + i)),
968 __free_page(sg_page(sg + i));
969 sg_assign_page(sg + i, NULL);
979 } while (len && sgl->cur < MAX_SGL_ENTS);
982 sg_mark_end(sg + sgl->cur - 1);
984 ctx->merge = plen & (PAGE_SIZE - 1);
989 ctx->more = msg->msg_flags & MSG_MORE;
992 af_alg_data_wakeup(sk);
995 return copied ?: err;
997 EXPORT_SYMBOL_GPL(af_alg_sendmsg);
1000 * af_alg_sendpage - sendpage system call handler
1002 * This is a generic implementation of sendpage to fill ctx->tsgl_list.
1004 ssize_t af_alg_sendpage(struct socket *sock, struct page *page,
1005 int offset, size_t size, int flags)
1007 struct sock *sk = sock->sk;
1008 struct alg_sock *ask = alg_sk(sk);
1009 struct af_alg_ctx *ctx = ask->private;
1010 struct af_alg_tsgl *sgl;
1013 if (flags & MSG_SENDPAGE_NOTLAST)
1017 if (!ctx->more && ctx->used)
1023 if (!af_alg_writable(sk)) {
1024 err = af_alg_wait_for_wmem(sk, flags);
1029 err = af_alg_alloc_tsgl(sk);
1034 sgl = list_entry(ctx->tsgl_list.prev, struct af_alg_tsgl, list);
1037 sg_unmark_end(sgl->sg + sgl->cur - 1);
1039 sg_mark_end(sgl->sg + sgl->cur);
1042 sg_set_page(sgl->sg + sgl->cur, page, size, offset);
1047 ctx->more = flags & MSG_MORE;
1050 af_alg_data_wakeup(sk);
1055 EXPORT_SYMBOL_GPL(af_alg_sendpage);
1058 * af_alg_free_resources - release resources required for crypto request
1060 void af_alg_free_resources(struct af_alg_async_req *areq)
1062 struct sock *sk = areq->sk;
1064 af_alg_free_areq_sgls(areq);
1065 sock_kfree_s(sk, areq, areq->areqlen);
1067 EXPORT_SYMBOL_GPL(af_alg_free_resources);
1070 * af_alg_async_cb - AIO callback handler
1072 * This handler cleans up the struct af_alg_async_req upon completion of the
1075 * The number of bytes to be generated with the AIO operation must be set
1076 * in areq->outlen before the AIO callback handler is invoked.
1078 void af_alg_async_cb(struct crypto_async_request *_req, int err)
1080 struct af_alg_async_req *areq = _req->data;
1081 struct sock *sk = areq->sk;
1082 struct kiocb *iocb = areq->iocb;
1083 unsigned int resultlen;
1085 /* Buffer size written by crypto operation. */
1086 resultlen = areq->outlen;
1088 af_alg_free_resources(areq);
1091 iocb->ki_complete(iocb, err ? err : (int)resultlen, 0);
1093 EXPORT_SYMBOL_GPL(af_alg_async_cb);
1096 * af_alg_poll - poll system call handler
1098 unsigned int af_alg_poll(struct file *file, struct socket *sock,
1101 struct sock *sk = sock->sk;
1102 struct alg_sock *ask = alg_sk(sk);
1103 struct af_alg_ctx *ctx = ask->private;
1106 sock_poll_wait(file, sk_sleep(sk), wait);
1109 if (!ctx->more || ctx->used)
1110 mask |= POLLIN | POLLRDNORM;
1112 if (af_alg_writable(sk))
1113 mask |= POLLOUT | POLLWRNORM | POLLWRBAND;
1117 EXPORT_SYMBOL_GPL(af_alg_poll);
1120 * af_alg_alloc_areq - allocate struct af_alg_async_req
1122 * @sk socket of connection to user space
1123 * @areqlen size of struct af_alg_async_req + crypto_*_reqsize
1124 * @return allocated data structure or ERR_PTR upon error
1126 struct af_alg_async_req *af_alg_alloc_areq(struct sock *sk,
1127 unsigned int areqlen)
1129 struct af_alg_async_req *areq = sock_kmalloc(sk, areqlen, GFP_KERNEL);
1131 if (unlikely(!areq))
1132 return ERR_PTR(-ENOMEM);
1134 areq->areqlen = areqlen;
1136 areq->last_rsgl = NULL;
1137 INIT_LIST_HEAD(&areq->rsgl_list);
1139 areq->tsgl_entries = 0;
1143 EXPORT_SYMBOL_GPL(af_alg_alloc_areq);
1146 * af_alg_get_rsgl - create the RX SGL for the output data from the crypto
1149 * @sk socket of connection to user space
1150 * @msg user space message
1151 * @flags flags used to invoke recvmsg with
1152 * @areq instance of the cryptographic request that will hold the RX SGL
1153 * @maxsize maximum number of bytes to be pulled from user space
1154 * @outlen number of bytes in the RX SGL
1155 * @return 0 on success, < 0 upon error
1157 int af_alg_get_rsgl(struct sock *sk, struct msghdr *msg, int flags,
1158 struct af_alg_async_req *areq, size_t maxsize,
1161 struct alg_sock *ask = alg_sk(sk);
1162 struct af_alg_ctx *ctx = ask->private;
1165 while (maxsize > len && msg_data_left(msg)) {
1166 struct af_alg_rsgl *rsgl;
1170 /* limit the amount of readable buffers */
1171 if (!af_alg_readable(sk))
1174 seglen = min_t(size_t, (maxsize - len),
1175 msg_data_left(msg));
1177 if (list_empty(&areq->rsgl_list)) {
1178 rsgl = &areq->first_rsgl;
1180 rsgl = sock_kmalloc(sk, sizeof(*rsgl), GFP_KERNEL);
1181 if (unlikely(!rsgl))
1185 rsgl->sgl.npages = 0;
1186 list_add_tail(&rsgl->list, &areq->rsgl_list);
1188 /* make one iovec available as scatterlist */
1189 err = af_alg_make_sg(&rsgl->sgl, &msg->msg_iter, seglen);
1191 rsgl->sg_num_bytes = 0;
1195 /* chain the new scatterlist with previous one */
1196 if (areq->last_rsgl)
1197 af_alg_link_sg(&areq->last_rsgl->sgl, &rsgl->sgl);
1199 areq->last_rsgl = rsgl;
1201 atomic_add(err, &ctx->rcvused);
1202 rsgl->sg_num_bytes = err;
1203 iov_iter_advance(&msg->msg_iter, err);
1209 EXPORT_SYMBOL_GPL(af_alg_get_rsgl);
1211 static int __init af_alg_init(void)
1213 int err = proto_register(&alg_proto, 0);
1218 err = sock_register(&alg_family);
1220 goto out_unregister_proto;
1225 out_unregister_proto:
1226 proto_unregister(&alg_proto);
1230 static void __exit af_alg_exit(void)
1232 sock_unregister(PF_ALG);
1233 proto_unregister(&alg_proto);
1236 module_init(af_alg_init);
1237 module_exit(af_alg_exit);
1238 MODULE_LICENSE("GPL");
1239 MODULE_ALIAS_NETPROTO(AF_ALG);