2 * algif_hash: User-space interface for hash algorithms
4 * This file provides the user-space API for hash 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 <crypto/hash.h>
16 #include <crypto/if_alg.h>
17 #include <linux/init.h>
18 #include <linux/kernel.h>
20 #include <linux/module.h>
21 #include <linux/net.h>
25 struct af_alg_sgl sgl;
29 struct af_alg_completion completion;
34 struct ahash_request req;
37 struct algif_hash_tfm {
38 struct crypto_ahash *hash;
42 static int hash_sendmsg(struct socket *sock, struct msghdr *msg,
45 int limit = ALG_MAX_PAGES * PAGE_SIZE;
46 struct sock *sk = sock->sk;
47 struct alg_sock *ask = alg_sk(sk);
48 struct hash_ctx *ctx = ask->private;
52 if (limit > sk->sk_sndbuf)
53 limit = sk->sk_sndbuf;
57 err = af_alg_wait_for_completion(crypto_ahash_init(&ctx->req),
65 while (msg_data_left(msg)) {
66 int len = msg_data_left(msg);
71 len = af_alg_make_sg(&ctx->sgl, &msg->msg_iter, len);
73 err = copied ? 0 : len;
77 ahash_request_set_crypt(&ctx->req, ctx->sgl.sg, NULL, len);
79 err = af_alg_wait_for_completion(crypto_ahash_update(&ctx->req),
81 af_alg_free_sg(&ctx->sgl);
86 iov_iter_advance(&msg->msg_iter, len);
91 ctx->more = msg->msg_flags & MSG_MORE;
93 ahash_request_set_crypt(&ctx->req, NULL, ctx->result, 0);
94 err = af_alg_wait_for_completion(crypto_ahash_final(&ctx->req),
101 return err ?: copied;
104 static ssize_t hash_sendpage(struct socket *sock, struct page *page,
105 int offset, size_t size, int flags)
107 struct sock *sk = sock->sk;
108 struct alg_sock *ask = alg_sk(sk);
109 struct hash_ctx *ctx = ask->private;
112 if (flags & MSG_SENDPAGE_NOTLAST)
116 sg_init_table(ctx->sgl.sg, 1);
117 sg_set_page(ctx->sgl.sg, page, size, offset);
119 ahash_request_set_crypt(&ctx->req, ctx->sgl.sg, ctx->result, size);
121 if (!(flags & MSG_MORE)) {
123 err = crypto_ahash_finup(&ctx->req);
125 err = crypto_ahash_digest(&ctx->req);
128 err = crypto_ahash_init(&ctx->req);
129 err = af_alg_wait_for_completion(err, &ctx->completion);
134 err = crypto_ahash_update(&ctx->req);
137 err = af_alg_wait_for_completion(err, &ctx->completion);
141 ctx->more = flags & MSG_MORE;
149 static int hash_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
152 struct sock *sk = sock->sk;
153 struct alg_sock *ask = alg_sk(sk);
154 struct hash_ctx *ctx = ask->private;
155 unsigned ds = crypto_ahash_digestsize(crypto_ahash_reqtfm(&ctx->req));
161 msg->msg_flags |= MSG_TRUNC;
166 ahash_request_set_crypt(&ctx->req, NULL, ctx->result, 0);
167 err = af_alg_wait_for_completion(crypto_ahash_final(&ctx->req),
173 err = memcpy_to_msg(msg, ctx->result, len);
181 static int hash_accept(struct socket *sock, struct socket *newsock, int flags)
183 struct sock *sk = sock->sk;
184 struct alg_sock *ask = alg_sk(sk);
185 struct hash_ctx *ctx = ask->private;
186 struct ahash_request *req = &ctx->req;
187 char state[crypto_ahash_statesize(crypto_ahash_reqtfm(req)) ? : 1];
189 struct alg_sock *ask2;
190 struct hash_ctx *ctx2;
196 err = more ? crypto_ahash_export(req, state) : 0;
202 err = af_alg_accept(ask->parent, newsock);
208 ctx2 = ask2->private;
214 err = crypto_ahash_import(&ctx2->req, state);
223 static struct proto_ops algif_hash_ops = {
226 .connect = sock_no_connect,
227 .socketpair = sock_no_socketpair,
228 .getname = sock_no_getname,
229 .ioctl = sock_no_ioctl,
230 .listen = sock_no_listen,
231 .shutdown = sock_no_shutdown,
232 .getsockopt = sock_no_getsockopt,
233 .mmap = sock_no_mmap,
234 .bind = sock_no_bind,
235 .setsockopt = sock_no_setsockopt,
236 .poll = sock_no_poll,
238 .release = af_alg_release,
239 .sendmsg = hash_sendmsg,
240 .sendpage = hash_sendpage,
241 .recvmsg = hash_recvmsg,
242 .accept = hash_accept,
245 static int hash_check_key(struct socket *sock)
249 struct alg_sock *pask;
250 struct algif_hash_tfm *tfm;
251 struct sock *sk = sock->sk;
252 struct alg_sock *ask = alg_sk(sk);
255 if (!atomic_read(&ask->nokey_refcnt))
259 pask = alg_sk(ask->parent);
263 lock_sock_nested(psk, SINGLE_DEPTH_NESTING);
267 atomic_dec(&pask->nokey_refcnt);
268 atomic_set(&ask->nokey_refcnt, 0);
280 static int hash_sendmsg_nokey(struct socket *sock, struct msghdr *msg,
285 err = hash_check_key(sock);
289 return hash_sendmsg(sock, msg, size);
292 static ssize_t hash_sendpage_nokey(struct socket *sock, struct page *page,
293 int offset, size_t size, int flags)
297 err = hash_check_key(sock);
301 return hash_sendpage(sock, page, offset, size, flags);
304 static int hash_recvmsg_nokey(struct socket *sock, struct msghdr *msg,
305 size_t ignored, int flags)
309 err = hash_check_key(sock);
313 return hash_recvmsg(sock, msg, ignored, flags);
316 static int hash_accept_nokey(struct socket *sock, struct socket *newsock,
321 err = hash_check_key(sock);
325 return hash_accept(sock, newsock, flags);
328 static struct proto_ops algif_hash_ops_nokey = {
331 .connect = sock_no_connect,
332 .socketpair = sock_no_socketpair,
333 .getname = sock_no_getname,
334 .ioctl = sock_no_ioctl,
335 .listen = sock_no_listen,
336 .shutdown = sock_no_shutdown,
337 .getsockopt = sock_no_getsockopt,
338 .mmap = sock_no_mmap,
339 .bind = sock_no_bind,
340 .setsockopt = sock_no_setsockopt,
341 .poll = sock_no_poll,
343 .release = af_alg_release,
344 .sendmsg = hash_sendmsg_nokey,
345 .sendpage = hash_sendpage_nokey,
346 .recvmsg = hash_recvmsg_nokey,
347 .accept = hash_accept_nokey,
350 static void *hash_bind(const char *name, u32 type, u32 mask)
352 struct algif_hash_tfm *tfm;
353 struct crypto_ahash *hash;
355 tfm = kzalloc(sizeof(*tfm), GFP_KERNEL);
357 return ERR_PTR(-ENOMEM);
359 hash = crypto_alloc_ahash(name, type, mask);
362 return ERR_CAST(hash);
370 static void hash_release(void *private)
372 struct algif_hash_tfm *tfm = private;
374 crypto_free_ahash(tfm->hash);
378 static int hash_setkey(void *private, const u8 *key, unsigned int keylen)
380 struct algif_hash_tfm *tfm = private;
383 err = crypto_ahash_setkey(tfm->hash, key, keylen);
389 static void hash_sock_destruct(struct sock *sk)
391 struct alg_sock *ask = alg_sk(sk);
392 struct hash_ctx *ctx = ask->private;
394 sock_kzfree_s(sk, ctx->result,
395 crypto_ahash_digestsize(crypto_ahash_reqtfm(&ctx->req)));
396 sock_kfree_s(sk, ctx, ctx->len);
397 af_alg_release_parent(sk);
400 static int hash_accept_parent_nokey(void *private, struct sock *sk)
402 struct hash_ctx *ctx;
403 struct alg_sock *ask = alg_sk(sk);
404 struct algif_hash_tfm *tfm = private;
405 struct crypto_ahash *hash = tfm->hash;
406 unsigned len = sizeof(*ctx) + crypto_ahash_reqsize(hash);
407 unsigned ds = crypto_ahash_digestsize(hash);
409 ctx = sock_kmalloc(sk, len, GFP_KERNEL);
413 ctx->result = sock_kmalloc(sk, ds, GFP_KERNEL);
415 sock_kfree_s(sk, ctx, len);
419 memset(ctx->result, 0, ds);
423 af_alg_init_completion(&ctx->completion);
427 ahash_request_set_tfm(&ctx->req, hash);
428 ahash_request_set_callback(&ctx->req, CRYPTO_TFM_REQ_MAY_BACKLOG,
429 af_alg_complete, &ctx->completion);
431 sk->sk_destruct = hash_sock_destruct;
436 static int hash_accept_parent(void *private, struct sock *sk)
438 struct algif_hash_tfm *tfm = private;
440 if (!tfm->has_key && crypto_ahash_has_setkey(tfm->hash))
443 return hash_accept_parent_nokey(private, sk);
446 static const struct af_alg_type algif_type_hash = {
448 .release = hash_release,
449 .setkey = hash_setkey,
450 .accept = hash_accept_parent,
451 .accept_nokey = hash_accept_parent_nokey,
452 .ops = &algif_hash_ops,
453 .ops_nokey = &algif_hash_ops_nokey,
458 static int __init algif_hash_init(void)
460 return af_alg_register_type(&algif_type_hash);
463 static void __exit algif_hash_exit(void)
465 int err = af_alg_unregister_type(&algif_type_hash);
469 module_init(algif_hash_init);
470 module_exit(algif_hash_exit);
471 MODULE_LICENSE("GPL");