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 static int hash_alloc_result(struct sock *sk, struct hash_ctx *ctx)
44 ds = crypto_ahash_digestsize(crypto_ahash_reqtfm(&ctx->req));
46 ctx->result = sock_kmalloc(sk, ds, GFP_KERNEL);
50 memset(ctx->result, 0, ds);
55 static void hash_free_result(struct sock *sk, struct hash_ctx *ctx)
62 ds = crypto_ahash_digestsize(crypto_ahash_reqtfm(&ctx->req));
64 sock_kzfree_s(sk, ctx->result, ds);
68 static int hash_sendmsg(struct socket *sock, struct msghdr *msg,
71 int limit = ALG_MAX_PAGES * PAGE_SIZE;
72 struct sock *sk = sock->sk;
73 struct alg_sock *ask = alg_sk(sk);
74 struct hash_ctx *ctx = ask->private;
78 if (limit > sk->sk_sndbuf)
79 limit = sk->sk_sndbuf;
83 if ((msg->msg_flags & MSG_MORE))
84 hash_free_result(sk, ctx);
86 err = af_alg_wait_for_completion(crypto_ahash_init(&ctx->req),
94 while (msg_data_left(msg)) {
95 int len = msg_data_left(msg);
100 len = af_alg_make_sg(&ctx->sgl, &msg->msg_iter, len);
102 err = copied ? 0 : len;
106 ahash_request_set_crypt(&ctx->req, ctx->sgl.sg, NULL, len);
108 err = af_alg_wait_for_completion(crypto_ahash_update(&ctx->req),
110 af_alg_free_sg(&ctx->sgl);
115 iov_iter_advance(&msg->msg_iter, len);
120 ctx->more = msg->msg_flags & MSG_MORE;
122 err = hash_alloc_result(sk, ctx);
126 ahash_request_set_crypt(&ctx->req, NULL, ctx->result, 0);
127 err = af_alg_wait_for_completion(crypto_ahash_final(&ctx->req),
134 return err ?: copied;
137 static ssize_t hash_sendpage(struct socket *sock, struct page *page,
138 int offset, size_t size, int flags)
140 struct sock *sk = sock->sk;
141 struct alg_sock *ask = alg_sk(sk);
142 struct hash_ctx *ctx = ask->private;
145 if (flags & MSG_SENDPAGE_NOTLAST)
149 sg_init_table(ctx->sgl.sg, 1);
150 sg_set_page(ctx->sgl.sg, page, size, offset);
152 if (!(flags & MSG_MORE)) {
153 err = hash_alloc_result(sk, ctx);
156 } else if (!ctx->more)
157 hash_free_result(sk, ctx);
159 ahash_request_set_crypt(&ctx->req, ctx->sgl.sg, ctx->result, size);
161 if (!(flags & MSG_MORE)) {
163 err = crypto_ahash_finup(&ctx->req);
165 err = crypto_ahash_digest(&ctx->req);
168 err = crypto_ahash_init(&ctx->req);
169 err = af_alg_wait_for_completion(err, &ctx->completion);
174 err = crypto_ahash_update(&ctx->req);
177 err = af_alg_wait_for_completion(err, &ctx->completion);
181 ctx->more = flags & MSG_MORE;
189 static int hash_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
192 struct sock *sk = sock->sk;
193 struct alg_sock *ask = alg_sk(sk);
194 struct hash_ctx *ctx = ask->private;
195 unsigned ds = crypto_ahash_digestsize(crypto_ahash_reqtfm(&ctx->req));
202 msg->msg_flags |= MSG_TRUNC;
205 result = ctx->result;
206 err = hash_alloc_result(sk, ctx);
210 ahash_request_set_crypt(&ctx->req, NULL, ctx->result, 0);
212 if (!result && !ctx->more) {
213 err = af_alg_wait_for_completion(
214 crypto_ahash_init(&ctx->req),
220 if (!result || ctx->more) {
222 err = af_alg_wait_for_completion(crypto_ahash_final(&ctx->req),
228 err = memcpy_to_msg(msg, ctx->result, len);
231 hash_free_result(sk, ctx);
237 static int hash_accept(struct socket *sock, struct socket *newsock, int flags)
239 struct sock *sk = sock->sk;
240 struct alg_sock *ask = alg_sk(sk);
241 struct hash_ctx *ctx = ask->private;
242 struct ahash_request *req = &ctx->req;
243 char state[crypto_ahash_statesize(crypto_ahash_reqtfm(req)) ? : 1];
245 struct alg_sock *ask2;
246 struct hash_ctx *ctx2;
252 err = more ? crypto_ahash_export(req, state) : 0;
258 err = af_alg_accept(ask->parent, newsock);
264 ctx2 = ask2->private;
270 err = crypto_ahash_import(&ctx2->req, state);
279 static struct proto_ops algif_hash_ops = {
282 .connect = sock_no_connect,
283 .socketpair = sock_no_socketpair,
284 .getname = sock_no_getname,
285 .ioctl = sock_no_ioctl,
286 .listen = sock_no_listen,
287 .shutdown = sock_no_shutdown,
288 .getsockopt = sock_no_getsockopt,
289 .mmap = sock_no_mmap,
290 .bind = sock_no_bind,
291 .setsockopt = sock_no_setsockopt,
292 .poll = sock_no_poll,
294 .release = af_alg_release,
295 .sendmsg = hash_sendmsg,
296 .sendpage = hash_sendpage,
297 .recvmsg = hash_recvmsg,
298 .accept = hash_accept,
301 static int hash_check_key(struct socket *sock)
305 struct alg_sock *pask;
306 struct crypto_ahash *tfm;
307 struct sock *sk = sock->sk;
308 struct alg_sock *ask = alg_sk(sk);
311 if (!atomic_read(&ask->nokey_refcnt))
315 pask = alg_sk(ask->parent);
319 lock_sock_nested(psk, SINGLE_DEPTH_NESTING);
320 if (crypto_ahash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
323 atomic_dec(&pask->nokey_refcnt);
324 atomic_set(&ask->nokey_refcnt, 0);
336 static int hash_sendmsg_nokey(struct socket *sock, struct msghdr *msg,
341 err = hash_check_key(sock);
345 return hash_sendmsg(sock, msg, size);
348 static ssize_t hash_sendpage_nokey(struct socket *sock, struct page *page,
349 int offset, size_t size, int flags)
353 err = hash_check_key(sock);
357 return hash_sendpage(sock, page, offset, size, flags);
360 static int hash_recvmsg_nokey(struct socket *sock, struct msghdr *msg,
361 size_t ignored, int flags)
365 err = hash_check_key(sock);
369 return hash_recvmsg(sock, msg, ignored, flags);
372 static int hash_accept_nokey(struct socket *sock, struct socket *newsock,
377 err = hash_check_key(sock);
381 return hash_accept(sock, newsock, flags);
384 static struct proto_ops algif_hash_ops_nokey = {
387 .connect = sock_no_connect,
388 .socketpair = sock_no_socketpair,
389 .getname = sock_no_getname,
390 .ioctl = sock_no_ioctl,
391 .listen = sock_no_listen,
392 .shutdown = sock_no_shutdown,
393 .getsockopt = sock_no_getsockopt,
394 .mmap = sock_no_mmap,
395 .bind = sock_no_bind,
396 .setsockopt = sock_no_setsockopt,
397 .poll = sock_no_poll,
399 .release = af_alg_release,
400 .sendmsg = hash_sendmsg_nokey,
401 .sendpage = hash_sendpage_nokey,
402 .recvmsg = hash_recvmsg_nokey,
403 .accept = hash_accept_nokey,
406 static void *hash_bind(const char *name, u32 type, u32 mask)
408 return crypto_alloc_ahash(name, type, mask);
411 static void hash_release(void *private)
413 crypto_free_ahash(private);
416 static int hash_setkey(void *private, const u8 *key, unsigned int keylen)
418 return crypto_ahash_setkey(private, key, keylen);
421 static void hash_sock_destruct(struct sock *sk)
423 struct alg_sock *ask = alg_sk(sk);
424 struct hash_ctx *ctx = ask->private;
426 hash_free_result(sk, ctx);
427 sock_kfree_s(sk, ctx, ctx->len);
428 af_alg_release_parent(sk);
431 static int hash_accept_parent_nokey(void *private, struct sock *sk)
433 struct crypto_ahash *tfm = private;
434 struct alg_sock *ask = alg_sk(sk);
435 struct hash_ctx *ctx;
436 unsigned int len = sizeof(*ctx) + crypto_ahash_reqsize(tfm);
438 ctx = sock_kmalloc(sk, len, GFP_KERNEL);
445 af_alg_init_completion(&ctx->completion);
449 ahash_request_set_tfm(&ctx->req, tfm);
450 ahash_request_set_callback(&ctx->req, CRYPTO_TFM_REQ_MAY_BACKLOG,
451 af_alg_complete, &ctx->completion);
453 sk->sk_destruct = hash_sock_destruct;
458 static int hash_accept_parent(void *private, struct sock *sk)
460 struct crypto_ahash *tfm = private;
462 if (crypto_ahash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
465 return hash_accept_parent_nokey(private, sk);
468 static const struct af_alg_type algif_type_hash = {
470 .release = hash_release,
471 .setkey = hash_setkey,
472 .accept = hash_accept_parent,
473 .accept_nokey = hash_accept_parent_nokey,
474 .ops = &algif_hash_ops,
475 .ops_nokey = &algif_hash_ops_nokey,
480 static int __init algif_hash_init(void)
482 return af_alg_register_type(&algif_type_hash);
485 static void __exit algif_hash_exit(void)
487 int err = af_alg_unregister_type(&algif_type_hash);
491 module_init(algif_hash_init);
492 module_exit(algif_hash_exit);
493 MODULE_LICENSE("GPL");