blob: 850246206b1258a697f83e86c39acc9b0a17f973 [file] [log] [blame]
Herbert Xufe869cd2010-10-19 21:23:00 +08001/*
2 * algif_hash: User-space interface for hash algorithms
3 *
4 * This file provides the user-space API for hash algorithms.
5 *
6 * Copyright (c) 2010 Herbert Xu <herbert@gondor.apana.org.au>
7 *
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)
11 * any later version.
12 *
13 */
14
15#include <crypto/hash.h>
16#include <crypto/if_alg.h>
17#include <linux/init.h>
18#include <linux/kernel.h>
19#include <linux/mm.h>
20#include <linux/module.h>
21#include <linux/net.h>
22#include <net/sock.h>
23
24struct hash_ctx {
25 struct af_alg_sgl sgl;
26
27 u8 *result;
28
29 struct af_alg_completion completion;
30
31 unsigned int len;
32 bool more;
33
34 struct ahash_request req;
35};
36
37static int hash_sendmsg(struct kiocb *unused, struct socket *sock,
38 struct msghdr *msg, size_t ignored)
39{
40 int limit = ALG_MAX_PAGES * PAGE_SIZE;
41 struct sock *sk = sock->sk;
42 struct alg_sock *ask = alg_sk(sk);
43 struct hash_ctx *ctx = ask->private;
44 unsigned long iovlen;
45 struct iovec *iov;
46 long copied = 0;
47 int err;
48
49 if (limit > sk->sk_sndbuf)
50 limit = sk->sk_sndbuf;
51
52 lock_sock(sk);
53 if (!ctx->more) {
54 err = crypto_ahash_init(&ctx->req);
55 if (err)
56 goto unlock;
57 }
58
59 ctx->more = 0;
60
61 for (iov = msg->msg_iov, iovlen = msg->msg_iovlen; iovlen > 0;
62 iovlen--, iov++) {
63 unsigned long seglen = iov->iov_len;
64 char __user *from = iov->iov_base;
65
66 while (seglen) {
67 int len = min_t(unsigned long, seglen, limit);
68 int newlen;
69
70 newlen = af_alg_make_sg(&ctx->sgl, from, len, 0);
Herbert Xu269230e2011-06-27 15:45:19 +080071 if (newlen < 0) {
72 err = copied ? 0 : newlen;
Herbert Xufe869cd2010-10-19 21:23:00 +080073 goto unlock;
Herbert Xu269230e2011-06-27 15:45:19 +080074 }
Herbert Xufe869cd2010-10-19 21:23:00 +080075
76 ahash_request_set_crypt(&ctx->req, ctx->sgl.sg, NULL,
77 newlen);
78
79 err = af_alg_wait_for_completion(
80 crypto_ahash_update(&ctx->req),
81 &ctx->completion);
82
83 af_alg_free_sg(&ctx->sgl);
84
85 if (err)
86 goto unlock;
87
88 seglen -= newlen;
89 from += newlen;
90 copied += newlen;
91 }
92 }
93
94 err = 0;
95
96 ctx->more = msg->msg_flags & MSG_MORE;
97 if (!ctx->more) {
98 ahash_request_set_crypt(&ctx->req, NULL, ctx->result, 0);
99 err = af_alg_wait_for_completion(crypto_ahash_final(&ctx->req),
100 &ctx->completion);
101 }
102
103unlock:
104 release_sock(sk);
105
106 return err ?: copied;
107}
108
109static ssize_t hash_sendpage(struct socket *sock, struct page *page,
110 int offset, size_t size, int flags)
111{
112 struct sock *sk = sock->sk;
113 struct alg_sock *ask = alg_sk(sk);
114 struct hash_ctx *ctx = ask->private;
115 int err;
116
Shawn Landdend3f7d562013-11-24 22:36:28 -0800117 if (flags & MSG_SENDPAGE_NOTLAST)
118 flags |= MSG_MORE;
119
Herbert Xufe869cd2010-10-19 21:23:00 +0800120 lock_sock(sk);
121 sg_init_table(ctx->sgl.sg, 1);
122 sg_set_page(ctx->sgl.sg, page, size, offset);
123
124 ahash_request_set_crypt(&ctx->req, ctx->sgl.sg, ctx->result, size);
125
126 if (!(flags & MSG_MORE)) {
127 if (ctx->more)
128 err = crypto_ahash_finup(&ctx->req);
129 else
130 err = crypto_ahash_digest(&ctx->req);
131 } else {
132 if (!ctx->more) {
133 err = crypto_ahash_init(&ctx->req);
134 if (err)
135 goto unlock;
136 }
137
138 err = crypto_ahash_update(&ctx->req);
139 }
140
141 err = af_alg_wait_for_completion(err, &ctx->completion);
142 if (err)
143 goto unlock;
144
145 ctx->more = flags & MSG_MORE;
146
147unlock:
148 release_sock(sk);
149
150 return err ?: size;
151}
152
153static int hash_recvmsg(struct kiocb *unused, struct socket *sock,
154 struct msghdr *msg, size_t len, int flags)
155{
156 struct sock *sk = sock->sk;
157 struct alg_sock *ask = alg_sk(sk);
158 struct hash_ctx *ctx = ask->private;
159 unsigned ds = crypto_ahash_digestsize(crypto_ahash_reqtfm(&ctx->req));
160 int err;
161
162 if (len > ds)
163 len = ds;
164 else if (len < ds)
165 msg->msg_flags |= MSG_TRUNC;
166
Herbert Xufe869cd2010-10-19 21:23:00 +0800167 lock_sock(sk);
168 if (ctx->more) {
169 ctx->more = 0;
170 ahash_request_set_crypt(&ctx->req, NULL, ctx->result, 0);
171 err = af_alg_wait_for_completion(crypto_ahash_final(&ctx->req),
172 &ctx->completion);
173 if (err)
174 goto unlock;
175 }
176
177 err = memcpy_toiovec(msg->msg_iov, ctx->result, len);
178
179unlock:
180 release_sock(sk);
181
182 return err ?: len;
183}
184
185static int hash_accept(struct socket *sock, struct socket *newsock, int flags)
186{
187 struct sock *sk = sock->sk;
188 struct alg_sock *ask = alg_sk(sk);
189 struct hash_ctx *ctx = ask->private;
190 struct ahash_request *req = &ctx->req;
191 char state[crypto_ahash_statesize(crypto_ahash_reqtfm(req))];
192 struct sock *sk2;
193 struct alg_sock *ask2;
194 struct hash_ctx *ctx2;
195 int err;
196
197 err = crypto_ahash_export(req, state);
198 if (err)
199 return err;
200
201 err = af_alg_accept(ask->parent, newsock);
202 if (err)
203 return err;
204
205 sk2 = newsock->sk;
206 ask2 = alg_sk(sk2);
207 ctx2 = ask2->private;
208 ctx2->more = 1;
209
210 err = crypto_ahash_import(&ctx2->req, state);
211 if (err) {
212 sock_orphan(sk2);
213 sock_put(sk2);
214 }
215
216 return err;
217}
218
219static struct proto_ops algif_hash_ops = {
220 .family = PF_ALG,
221
222 .connect = sock_no_connect,
223 .socketpair = sock_no_socketpair,
224 .getname = sock_no_getname,
225 .ioctl = sock_no_ioctl,
226 .listen = sock_no_listen,
227 .shutdown = sock_no_shutdown,
228 .getsockopt = sock_no_getsockopt,
229 .mmap = sock_no_mmap,
230 .bind = sock_no_bind,
231 .setsockopt = sock_no_setsockopt,
232 .poll = sock_no_poll,
233
234 .release = af_alg_release,
235 .sendmsg = hash_sendmsg,
236 .sendpage = hash_sendpage,
237 .recvmsg = hash_recvmsg,
238 .accept = hash_accept,
239};
240
241static void *hash_bind(const char *name, u32 type, u32 mask)
242{
243 return crypto_alloc_ahash(name, type, mask);
244}
245
246static void hash_release(void *private)
247{
248 crypto_free_ahash(private);
249}
250
251static int hash_setkey(void *private, const u8 *key, unsigned int keylen)
252{
253 return crypto_ahash_setkey(private, key, keylen);
254}
255
256static void hash_sock_destruct(struct sock *sk)
257{
258 struct alg_sock *ask = alg_sk(sk);
259 struct hash_ctx *ctx = ask->private;
260
261 sock_kfree_s(sk, ctx->result,
262 crypto_ahash_digestsize(crypto_ahash_reqtfm(&ctx->req)));
263 sock_kfree_s(sk, ctx, ctx->len);
264 af_alg_release_parent(sk);
265}
266
267static int hash_accept_parent(void *private, struct sock *sk)
268{
269 struct hash_ctx *ctx;
270 struct alg_sock *ask = alg_sk(sk);
271 unsigned len = sizeof(*ctx) + crypto_ahash_reqsize(private);
272 unsigned ds = crypto_ahash_digestsize(private);
273
274 ctx = sock_kmalloc(sk, len, GFP_KERNEL);
275 if (!ctx)
276 return -ENOMEM;
277
278 ctx->result = sock_kmalloc(sk, ds, GFP_KERNEL);
279 if (!ctx->result) {
280 sock_kfree_s(sk, ctx, len);
281 return -ENOMEM;
282 }
283
284 memset(ctx->result, 0, ds);
285
286 ctx->len = len;
287 ctx->more = 0;
288 af_alg_init_completion(&ctx->completion);
289
290 ask->private = ctx;
291
292 ahash_request_set_tfm(&ctx->req, private);
293 ahash_request_set_callback(&ctx->req, CRYPTO_TFM_REQ_MAY_BACKLOG,
294 af_alg_complete, &ctx->completion);
295
296 sk->sk_destruct = hash_sock_destruct;
297
298 return 0;
299}
300
301static const struct af_alg_type algif_type_hash = {
302 .bind = hash_bind,
303 .release = hash_release,
304 .setkey = hash_setkey,
305 .accept = hash_accept_parent,
306 .ops = &algif_hash_ops,
307 .name = "hash",
308 .owner = THIS_MODULE
309};
310
311static int __init algif_hash_init(void)
312{
313 return af_alg_register_type(&algif_type_hash);
314}
315
316static void __exit algif_hash_exit(void)
317{
318 int err = af_alg_unregister_type(&algif_type_hash);
319 BUG_ON(err);
320}
321
322module_init(algif_hash_init);
323module_exit(algif_hash_exit);
324MODULE_LICENSE("GPL");