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/security.h>
26 struct alg_type_list {
27 const struct af_alg_type *type;
28 struct list_head list;
31 static atomic_long_t alg_memory_allocated;
33 static struct proto alg_proto = {
36 .memory_allocated = &alg_memory_allocated,
37 .obj_size = sizeof(struct alg_sock),
40 static LIST_HEAD(alg_types);
41 static DECLARE_RWSEM(alg_types_sem);
43 static const struct af_alg_type *alg_get_type(const char *name)
45 const struct af_alg_type *type = ERR_PTR(-ENOENT);
46 struct alg_type_list *node;
48 down_read(&alg_types_sem);
49 list_for_each_entry(node, &alg_types, list) {
50 if (strcmp(node->type->name, name))
53 if (try_module_get(node->type->owner))
57 up_read(&alg_types_sem);
62 int af_alg_register_type(const struct af_alg_type *type)
64 struct alg_type_list *node;
67 down_write(&alg_types_sem);
68 list_for_each_entry(node, &alg_types, list) {
69 if (!strcmp(node->type->name, type->name))
73 node = kmalloc(sizeof(*node), GFP_KERNEL);
78 type->ops->owner = THIS_MODULE;
80 list_add(&node->list, &alg_types);
84 up_write(&alg_types_sem);
88 EXPORT_SYMBOL_GPL(af_alg_register_type);
90 int af_alg_unregister_type(const struct af_alg_type *type)
92 struct alg_type_list *node;
95 down_write(&alg_types_sem);
96 list_for_each_entry(node, &alg_types, list) {
97 if (strcmp(node->type->name, type->name))
100 list_del(&node->list);
105 up_write(&alg_types_sem);
109 EXPORT_SYMBOL_GPL(af_alg_unregister_type);
111 static void alg_do_release(const struct af_alg_type *type, void *private)
116 type->release(private);
117 module_put(type->owner);
120 int af_alg_release(struct socket *sock)
126 EXPORT_SYMBOL_GPL(af_alg_release);
128 void af_alg_release_parent(struct sock *sk)
130 struct alg_sock *ask = alg_sk(sk);
137 last = !--ask->refcnt;
143 EXPORT_SYMBOL_GPL(af_alg_release_parent);
145 static int alg_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
147 const u32 forbidden = CRYPTO_ALG_INTERNAL;
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;
155 if (sock->state == SS_CONNECTED)
158 if (addr_len != sizeof(*sa))
161 sa->salg_type[sizeof(sa->salg_type) - 1] = 0;
162 sa->salg_name[sizeof(sa->salg_name) - 1] = 0;
164 type = alg_get_type(sa->salg_type);
165 if (IS_ERR(type) && PTR_ERR(type) == -ENOENT) {
166 request_module("algif-%s", sa->salg_type);
167 type = alg_get_type(sa->salg_type);
171 return PTR_ERR(type);
173 private = type->bind(sa->salg_name,
174 sa->salg_feat & ~forbidden,
175 sa->salg_mask & ~forbidden);
176 if (IS_ERR(private)) {
177 module_put(type->owner);
178 return PTR_ERR(private);
186 swap(ask->type, type);
187 swap(ask->private, private);
194 alg_do_release(type, private);
199 static int alg_setkey(struct sock *sk, char __user *ukey,
202 struct alg_sock *ask = alg_sk(sk);
203 const struct af_alg_type *type = ask->type;
207 key = sock_kmalloc(sk, keylen, GFP_KERNEL);
212 if (copy_from_user(key, ukey, keylen))
215 err = type->setkey(ask->private, key, keylen);
218 sock_kzfree_s(sk, key, keylen);
223 static int alg_setsockopt(struct socket *sock, int level, int optname,
224 char __user *optval, unsigned int optlen)
226 struct sock *sk = sock->sk;
227 struct alg_sock *ask = alg_sk(sk);
228 const struct af_alg_type *type;
238 if (level != SOL_ALG || !type)
243 if (sock->state == SS_CONNECTED)
248 err = alg_setkey(sk, optval, optlen);
250 case ALG_SET_AEAD_AUTHSIZE:
251 if (sock->state == SS_CONNECTED)
253 if (!type->setauthsize)
255 err = type->setauthsize(ask->private, optlen);
264 int af_alg_accept(struct sock *sk, struct socket *newsock)
266 struct alg_sock *ask = alg_sk(sk);
267 const struct af_alg_type *type;
278 sk2 = sk_alloc(sock_net(sk), PF_ALG, GFP_KERNEL, &alg_proto, 0);
283 sock_init_data(newsock, sk2);
284 sock_graft(sk2, newsock);
285 security_sk_clone(sk, sk2);
287 err = type->accept(ask->private, sk2);
291 sk2->sk_family = PF_ALG;
295 alg_sk(sk2)->parent = sk;
296 alg_sk(sk2)->type = type;
298 newsock->ops = type->ops;
299 newsock->state = SS_CONNECTED;
308 EXPORT_SYMBOL_GPL(af_alg_accept);
310 static int alg_accept(struct socket *sock, struct socket *newsock, int flags)
312 return af_alg_accept(sock->sk, newsock);
315 static const struct proto_ops alg_proto_ops = {
317 .owner = THIS_MODULE,
319 .connect = sock_no_connect,
320 .socketpair = sock_no_socketpair,
321 .getname = sock_no_getname,
322 .ioctl = sock_no_ioctl,
323 .listen = sock_no_listen,
324 .shutdown = sock_no_shutdown,
325 .getsockopt = sock_no_getsockopt,
326 .mmap = sock_no_mmap,
327 .sendpage = sock_no_sendpage,
328 .sendmsg = sock_no_sendmsg,
329 .recvmsg = sock_no_recvmsg,
330 .poll = sock_no_poll,
333 .release = af_alg_release,
334 .setsockopt = alg_setsockopt,
335 .accept = alg_accept,
338 static void alg_sock_destruct(struct sock *sk)
340 struct alg_sock *ask = alg_sk(sk);
342 alg_do_release(ask->type, ask->private);
345 static int alg_create(struct net *net, struct socket *sock, int protocol,
351 if (sock->type != SOCK_SEQPACKET)
352 return -ESOCKTNOSUPPORT;
354 return -EPROTONOSUPPORT;
357 sk = sk_alloc(net, PF_ALG, GFP_KERNEL, &alg_proto, kern);
361 sock->ops = &alg_proto_ops;
362 sock_init_data(sock, sk);
364 sk->sk_family = PF_ALG;
365 sk->sk_destruct = alg_sock_destruct;
372 static const struct net_proto_family alg_family = {
374 .create = alg_create,
375 .owner = THIS_MODULE,
378 int af_alg_make_sg(struct af_alg_sgl *sgl, struct iov_iter *iter, int len)
384 n = iov_iter_get_pages(iter, sgl->pages, len, ALG_MAX_PAGES, &off);
388 npages = (off + n + PAGE_SIZE - 1) >> PAGE_SHIFT;
389 if (WARN_ON(npages == 0))
391 /* Add one extra for linking */
392 sg_init_table(sgl->sg, npages + 1);
394 for (i = 0, len = n; i < npages; i++) {
395 int plen = min_t(int, len, PAGE_SIZE - off);
397 sg_set_page(sgl->sg + i, sgl->pages[i], plen, off);
402 sg_mark_end(sgl->sg + npages - 1);
403 sgl->npages = npages;
407 EXPORT_SYMBOL_GPL(af_alg_make_sg);
409 void af_alg_link_sg(struct af_alg_sgl *sgl_prev, struct af_alg_sgl *sgl_new)
411 sg_unmark_end(sgl_prev->sg + sgl_prev->npages - 1);
412 sg_chain(sgl_prev->sg, sgl_prev->npages + 1, sgl_new->sg);
414 EXPORT_SYMBOL_GPL(af_alg_link_sg);
416 void af_alg_free_sg(struct af_alg_sgl *sgl)
420 for (i = 0; i < sgl->npages; i++)
421 put_page(sgl->pages[i]);
423 EXPORT_SYMBOL_GPL(af_alg_free_sg);
425 int af_alg_cmsg_send(struct msghdr *msg, struct af_alg_control *con)
427 struct cmsghdr *cmsg;
429 for_each_cmsghdr(cmsg, msg) {
430 if (!CMSG_OK(msg, cmsg))
432 if (cmsg->cmsg_level != SOL_ALG)
435 switch (cmsg->cmsg_type) {
437 if (cmsg->cmsg_len < CMSG_LEN(sizeof(*con->iv)))
439 con->iv = (void *)CMSG_DATA(cmsg);
440 if (cmsg->cmsg_len < CMSG_LEN(con->iv->ivlen +
446 if (cmsg->cmsg_len < CMSG_LEN(sizeof(u32)))
448 con->op = *(u32 *)CMSG_DATA(cmsg);
451 case ALG_SET_AEAD_ASSOCLEN:
452 if (cmsg->cmsg_len < CMSG_LEN(sizeof(u32)))
454 con->aead_assoclen = *(u32 *)CMSG_DATA(cmsg);
464 EXPORT_SYMBOL_GPL(af_alg_cmsg_send);
466 int af_alg_wait_for_completion(int err, struct af_alg_completion *completion)
471 wait_for_completion(&completion->completion);
472 reinit_completion(&completion->completion);
473 err = completion->err;
479 EXPORT_SYMBOL_GPL(af_alg_wait_for_completion);
481 void af_alg_complete(struct crypto_async_request *req, int err)
483 struct af_alg_completion *completion = req->data;
485 if (err == -EINPROGRESS)
488 completion->err = err;
489 complete(&completion->completion);
491 EXPORT_SYMBOL_GPL(af_alg_complete);
493 static int __init af_alg_init(void)
495 int err = proto_register(&alg_proto, 0);
500 err = sock_register(&alg_family);
502 goto out_unregister_proto;
507 out_unregister_proto:
508 proto_unregister(&alg_proto);
512 static void __exit af_alg_exit(void)
514 sock_unregister(PF_ALG);
515 proto_unregister(&alg_proto);
518 module_init(af_alg_init);
519 module_exit(af_alg_exit);
520 MODULE_LICENSE("GPL");
521 MODULE_ALIAS_NETPROTO(AF_ALG);