ublk: simplify aborting request
[linux-block.git] / crypto / algif_hash.c
CommitLineData
2874c5fd 1// SPDX-License-Identifier: GPL-2.0-or-later
fe869cdb
HX
2/*
3 * algif_hash: User-space interface for hash algorithms
4 *
5 * This file provides the user-space API for hash algorithms.
6 *
7 * Copyright (c) 2010 Herbert Xu <herbert@gondor.apana.org.au>
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8 */
9
10#include <crypto/hash.h>
11#include <crypto/if_alg.h>
12#include <linux/init.h>
13#include <linux/kernel.h>
14#include <linux/mm.h>
15#include <linux/module.h>
16#include <linux/net.h>
17#include <net/sock.h>
18
19struct hash_ctx {
20 struct af_alg_sgl sgl;
21
22 u8 *result;
23
2c3f8b16 24 struct crypto_wait wait;
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25
26 unsigned int len;
27 bool more;
28
29 struct ahash_request req;
30};
31
493b2ed3
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32static int hash_alloc_result(struct sock *sk, struct hash_ctx *ctx)
33{
34 unsigned ds;
35
36 if (ctx->result)
37 return 0;
38
39 ds = crypto_ahash_digestsize(crypto_ahash_reqtfm(&ctx->req));
40
41 ctx->result = sock_kmalloc(sk, ds, GFP_KERNEL);
42 if (!ctx->result)
43 return -ENOMEM;
44
45 memset(ctx->result, 0, ds);
46
47 return 0;
48}
49
50static void hash_free_result(struct sock *sk, struct hash_ctx *ctx)
51{
52 unsigned ds;
53
54 if (!ctx->result)
55 return;
56
57 ds = crypto_ahash_digestsize(crypto_ahash_reqtfm(&ctx->req));
58
59 sock_kzfree_s(sk, ctx->result, ds);
60 ctx->result = NULL;
61}
62
1b784140
YX
63static int hash_sendmsg(struct socket *sock, struct msghdr *msg,
64 size_t ignored)
fe869cdb 65{
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66 struct sock *sk = sock->sk;
67 struct alg_sock *ask = alg_sk(sk);
68 struct hash_ctx *ctx = ask->private;
c662b043
DH
69 ssize_t copied = 0;
70 size_t len, max_pages, npages;
0b7ec177 71 bool continuing, need_init = false;
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72 int err;
73
c662b043
DH
74 max_pages = min_t(size_t, ALG_MAX_PAGES,
75 DIV_ROUND_UP(sk->sk_sndbuf, PAGE_SIZE));
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76
77 lock_sock(sk);
0b7ec177
DH
78 continuing = ctx->more;
79
c662b043 80 if (!continuing) {
b6d972f6
DH
81 /* Discard a previous request that wasn't marked MSG_MORE. */
82 hash_free_result(sk, ctx);
83 if (!msg_data_left(msg))
84 goto done; /* Zero-length; don't start new req */
c662b043 85 need_init = true;
b6d972f6
DH
86 } else if (!msg_data_left(msg)) {
87 /*
88 * No data - finalise the prev req if MSG_MORE so any error
89 * comes out here.
90 */
91 if (!(msg->msg_flags & MSG_MORE)) {
92 err = hash_alloc_result(sk, ctx);
93 if (err)
94 goto unlock_free;
95 ahash_request_set_crypt(&ctx->req, NULL,
96 ctx->result, 0);
97 err = crypto_wait_req(crypto_ahash_final(&ctx->req),
98 &ctx->wait);
99 if (err)
100 goto unlock_free;
101 }
102 goto done_more;
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103 }
104
01e97e65 105 while (msg_data_left(msg)) {
c1abe6f5
DH
106 ctx->sgl.sgt.sgl = ctx->sgl.sgl;
107 ctx->sgl.sgt.nents = 0;
108 ctx->sgl.sgt.orig_nents = 0;
109
c662b043
DH
110 err = -EIO;
111 npages = iov_iter_npages(&msg->msg_iter, max_pages);
112 if (npages == 0)
113 goto unlock_free;
114
c662b043 115 sg_init_table(ctx->sgl.sgl, npages);
c1abe6f5
DH
116
117 ctx->sgl.need_unpin = iov_iter_extract_will_pin(&msg->msg_iter);
fe869cdb 118
c662b043
DH
119 err = extract_iter_to_sg(&msg->msg_iter, LONG_MAX,
120 &ctx->sgl.sgt, npages, 0);
121 if (err < 0)
122 goto unlock_free;
123 len = err;
124 sg_mark_end(ctx->sgl.sgt.sgl + ctx->sgl.sgt.nents - 1);
125
126 if (!msg_data_left(msg)) {
127 err = hash_alloc_result(sk, ctx);
128 if (err)
129 goto unlock_free;
dc5801f6 130 }
fe869cdb 131
c662b043
DH
132 ahash_request_set_crypt(&ctx->req, ctx->sgl.sgt.sgl,
133 ctx->result, len);
134
135 if (!msg_data_left(msg) && !continuing &&
136 !(msg->msg_flags & MSG_MORE)) {
137 err = crypto_ahash_digest(&ctx->req);
138 } else {
139 if (need_init) {
140 err = crypto_wait_req(
141 crypto_ahash_init(&ctx->req),
142 &ctx->wait);
143 if (err)
144 goto unlock_free;
145 need_init = false;
146 }
147
148 if (msg_data_left(msg) || (msg->msg_flags & MSG_MORE))
149 err = crypto_ahash_update(&ctx->req);
150 else
151 err = crypto_ahash_finup(&ctx->req);
152 continuing = true;
153 }
fe869cdb 154
c662b043 155 err = crypto_wait_req(err, &ctx->wait);
493b2ed3 156 if (err)
c662b043 157 goto unlock_free;
493b2ed3 158
c662b043
DH
159 copied += len;
160 af_alg_free_sg(&ctx->sgl);
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161 }
162
b6d972f6 163done_more:
c662b043 164 ctx->more = msg->msg_flags & MSG_MORE;
b6d972f6 165done:
c662b043 166 err = 0;
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167unlock:
168 release_sock(sk);
c662b043 169 return copied ?: err;
fe869cdb 170
c662b043
DH
171unlock_free:
172 af_alg_free_sg(&ctx->sgl);
b6d972f6
DH
173 hash_free_result(sk, ctx);
174 ctx->more = false;
c662b043 175 goto unlock;
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176}
177
1b784140
YX
178static int hash_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
179 int flags)
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180{
181 struct sock *sk = sock->sk;
182 struct alg_sock *ask = alg_sk(sk);
183 struct hash_ctx *ctx = ask->private;
184 unsigned ds = crypto_ahash_digestsize(crypto_ahash_reqtfm(&ctx->req));
493b2ed3 185 bool result;
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186 int err;
187
188 if (len > ds)
189 len = ds;
190 else if (len < ds)
191 msg->msg_flags |= MSG_TRUNC;
192
193 lock_sock(sk);
493b2ed3
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194 result = ctx->result;
195 err = hash_alloc_result(sk, ctx);
196 if (err)
197 goto unlock;
198
199 ahash_request_set_crypt(&ctx->req, NULL, ctx->result, 0);
200
8acf7a10 201 if (!result && !ctx->more) {
2c3f8b16
GBY
202 err = crypto_wait_req(crypto_ahash_init(&ctx->req),
203 &ctx->wait);
a8348bca
HX
204 if (err)
205 goto unlock;
206 }
207
208 if (!result || ctx->more) {
fcb90d51 209 ctx->more = false;
2c3f8b16
GBY
210 err = crypto_wait_req(crypto_ahash_final(&ctx->req),
211 &ctx->wait);
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212 if (err)
213 goto unlock;
214 }
215
7eab8d9e 216 err = memcpy_to_msg(msg, ctx->result, len);
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217
218unlock:
a8348bca 219 hash_free_result(sk, ctx);
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220 release_sock(sk);
221
222 return err ?: len;
223}
224
cdfbabfb
DH
225static int hash_accept(struct socket *sock, struct socket *newsock, int flags,
226 bool kern)
fe869cdb
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227{
228 struct sock *sk = sock->sk;
229 struct alg_sock *ask = alg_sk(sk);
230 struct hash_ctx *ctx = ask->private;
231 struct ahash_request *req = &ctx->req;
acc03d89 232 struct crypto_ahash *tfm;
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233 struct sock *sk2;
234 struct alg_sock *ask2;
235 struct hash_ctx *ctx2;
acc03d89 236 char *state;
4afa5f96 237 bool more;
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238 int err;
239
acc03d89
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240 tfm = crypto_ahash_reqtfm(req);
241 state = kmalloc(crypto_ahash_statesize(tfm), GFP_KERNEL);
242 err = -ENOMEM;
243 if (!state)
244 goto out;
245
4afa5f96
HX
246 lock_sock(sk);
247 more = ctx->more;
248 err = more ? crypto_ahash_export(req, state) : 0;
249 release_sock(sk);
250
fe869cdb 251 if (err)
acc03d89 252 goto out_free_state;
fe869cdb 253
cdfbabfb 254 err = af_alg_accept(ask->parent, newsock, kern);
fe869cdb 255 if (err)
acc03d89 256 goto out_free_state;
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257
258 sk2 = newsock->sk;
259 ask2 = alg_sk(sk2);
260 ctx2 = ask2->private;
4afa5f96
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261 ctx2->more = more;
262
263 if (!more)
acc03d89 264 goto out_free_state;
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265
266 err = crypto_ahash_import(&ctx2->req, state);
267 if (err) {
268 sock_orphan(sk2);
269 sock_put(sk2);
270 }
271
acc03d89
HX
272out_free_state:
273 kfree_sensitive(state);
274
275out:
fe869cdb
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276 return err;
277}
278
279static struct proto_ops algif_hash_ops = {
280 .family = PF_ALG,
281
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,
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288 .mmap = sock_no_mmap,
289 .bind = sock_no_bind,
fe869cdb
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290
291 .release = af_alg_release,
292 .sendmsg = hash_sendmsg,
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293 .recvmsg = hash_recvmsg,
294 .accept = hash_accept,
295};
296
6de62f15
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297static int hash_check_key(struct socket *sock)
298{
ad46d7e3 299 int err = 0;
6de62f15
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300 struct sock *psk;
301 struct alg_sock *pask;
9fa68f62 302 struct crypto_ahash *tfm;
6de62f15
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303 struct sock *sk = sock->sk;
304 struct alg_sock *ask = alg_sk(sk);
305
ad46d7e3 306 lock_sock(sk);
34c86f4c 307 if (!atomic_read(&ask->nokey_refcnt))
ad46d7e3 308 goto unlock_child;
6de62f15
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309
310 psk = ask->parent;
311 pask = alg_sk(ask->parent);
312 tfm = pask->private;
313
314 err = -ENOKEY;
ad46d7e3 315 lock_sock_nested(psk, SINGLE_DEPTH_NESTING);
9fa68f62 316 if (crypto_ahash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
6de62f15
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317 goto unlock;
318
34c86f4c
HX
319 atomic_dec(&pask->nokey_refcnt);
320 atomic_set(&ask->nokey_refcnt, 0);
6de62f15
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321
322 err = 0;
323
324unlock:
325 release_sock(psk);
ad46d7e3
HX
326unlock_child:
327 release_sock(sk);
6de62f15
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328
329 return err;
330}
331
332static int hash_sendmsg_nokey(struct socket *sock, struct msghdr *msg,
333 size_t size)
334{
335 int err;
336
337 err = hash_check_key(sock);
338 if (err)
339 return err;
340
341 return hash_sendmsg(sock, msg, size);
342}
343
6de62f15
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344static int hash_recvmsg_nokey(struct socket *sock, struct msghdr *msg,
345 size_t ignored, int flags)
346{
347 int err;
348
349 err = hash_check_key(sock);
350 if (err)
351 return err;
352
353 return hash_recvmsg(sock, msg, ignored, flags);
354}
355
356static int hash_accept_nokey(struct socket *sock, struct socket *newsock,
cdfbabfb 357 int flags, bool kern)
6de62f15
HX
358{
359 int err;
360
361 err = hash_check_key(sock);
362 if (err)
363 return err;
364
cdfbabfb 365 return hash_accept(sock, newsock, flags, kern);
6de62f15
HX
366}
367
368static struct proto_ops algif_hash_ops_nokey = {
369 .family = PF_ALG,
370
371 .connect = sock_no_connect,
372 .socketpair = sock_no_socketpair,
373 .getname = sock_no_getname,
374 .ioctl = sock_no_ioctl,
375 .listen = sock_no_listen,
376 .shutdown = sock_no_shutdown,
6de62f15
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377 .mmap = sock_no_mmap,
378 .bind = sock_no_bind,
6de62f15
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379
380 .release = af_alg_release,
381 .sendmsg = hash_sendmsg_nokey,
6de62f15
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382 .recvmsg = hash_recvmsg_nokey,
383 .accept = hash_accept_nokey,
384};
385
fe869cdb
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386static void *hash_bind(const char *name, u32 type, u32 mask)
387{
9fa68f62 388 return crypto_alloc_ahash(name, type, mask);
fe869cdb
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389}
390
391static void hash_release(void *private)
392{
9fa68f62 393 crypto_free_ahash(private);
fe869cdb
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394}
395
396static int hash_setkey(void *private, const u8 *key, unsigned int keylen)
397{
9fa68f62 398 return crypto_ahash_setkey(private, key, keylen);
fe869cdb
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399}
400
f1d84af1 401static void hash_sock_destruct(struct sock *sk)
fe869cdb
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402{
403 struct alg_sock *ask = alg_sk(sk);
404 struct hash_ctx *ctx = ask->private;
405
493b2ed3 406 hash_free_result(sk, ctx);
fe869cdb 407 sock_kfree_s(sk, ctx, ctx->len);
6de62f15
HX
408 af_alg_release_parent(sk);
409}
410
f1d84af1 411static int hash_accept_parent_nokey(void *private, struct sock *sk)
fe869cdb 412{
9fa68f62 413 struct crypto_ahash *tfm = private;
fe869cdb 414 struct alg_sock *ask = alg_sk(sk);
9fa68f62
EB
415 struct hash_ctx *ctx;
416 unsigned int len = sizeof(*ctx) + crypto_ahash_reqsize(tfm);
fe869cdb
HX
417
418 ctx = sock_kmalloc(sk, len, GFP_KERNEL);
419 if (!ctx)
420 return -ENOMEM;
421
493b2ed3 422 ctx->result = NULL;
fe869cdb 423 ctx->len = len;
fcb90d51 424 ctx->more = false;
2c3f8b16 425 crypto_init_wait(&ctx->wait);
fe869cdb
HX
426
427 ask->private = ctx;
428
9fa68f62 429 ahash_request_set_tfm(&ctx->req, tfm);
fe869cdb 430 ahash_request_set_callback(&ctx->req, CRYPTO_TFM_REQ_MAY_BACKLOG,
2c3f8b16 431 crypto_req_done, &ctx->wait);
fe869cdb
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432
433 sk->sk_destruct = hash_sock_destruct;
434
435 return 0;
436}
437
6de62f15
HX
438static int hash_accept_parent(void *private, struct sock *sk)
439{
9fa68f62 440 struct crypto_ahash *tfm = private;
6de62f15 441
9fa68f62 442 if (crypto_ahash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
6de62f15
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443 return -ENOKEY;
444
f1d84af1 445 return hash_accept_parent_nokey(private, sk);
6de62f15
HX
446}
447
fe869cdb
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448static const struct af_alg_type algif_type_hash = {
449 .bind = hash_bind,
450 .release = hash_release,
451 .setkey = hash_setkey,
452 .accept = hash_accept_parent,
6de62f15 453 .accept_nokey = hash_accept_parent_nokey,
fe869cdb 454 .ops = &algif_hash_ops,
6de62f15 455 .ops_nokey = &algif_hash_ops_nokey,
fe869cdb
HX
456 .name = "hash",
457 .owner = THIS_MODULE
458};
459
460static int __init algif_hash_init(void)
461{
462 return af_alg_register_type(&algif_type_hash);
463}
464
465static void __exit algif_hash_exit(void)
466{
467 int err = af_alg_unregister_type(&algif_type_hash);
468 BUG_ON(err);
469}
470
471module_init(algif_hash_init);
472module_exit(algif_hash_exit);
473MODULE_LICENSE("GPL");