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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
37struct algif_hash_tfm {
38 struct crypto_ahash *hash;
39 bool has_key;
40};
41
42static int hash_alloc_result(struct sock *sk, struct hash_ctx *ctx)
43{
44 unsigned ds;
45
46 if (ctx->result)
47 return 0;
48
49 ds = crypto_ahash_digestsize(crypto_ahash_reqtfm(&ctx->req));
50
51 ctx->result = sock_kmalloc(sk, ds, GFP_KERNEL);
52 if (!ctx->result)
53 return -ENOMEM;
54
55 memset(ctx->result, 0, ds);
56
57 return 0;
58}
59
60static void hash_free_result(struct sock *sk, struct hash_ctx *ctx)
61{
62 unsigned ds;
63
64 if (!ctx->result)
65 return;
66
67 ds = crypto_ahash_digestsize(crypto_ahash_reqtfm(&ctx->req));
68
69 sock_kzfree_s(sk, ctx->result, ds);
70 ctx->result = NULL;
71}
72
73static int hash_sendmsg(struct socket *sock, struct msghdr *msg,
74 size_t ignored)
75{
76 int limit = ALG_MAX_PAGES * PAGE_SIZE;
77 struct sock *sk = sock->sk;
78 struct alg_sock *ask = alg_sk(sk);
79 struct hash_ctx *ctx = ask->private;
80 long copied = 0;
81 int err;
82
83 if (limit > sk->sk_sndbuf)
84 limit = sk->sk_sndbuf;
85
86 lock_sock(sk);
87 if (!ctx->more) {
88 if ((msg->msg_flags & MSG_MORE))
89 hash_free_result(sk, ctx);
90
91 err = af_alg_wait_for_completion(crypto_ahash_init(&ctx->req),
92 &ctx->completion);
93 if (err)
94 goto unlock;
95 }
96
97 ctx->more = 0;
98
99 while (msg_data_left(msg)) {
100 int len = msg_data_left(msg);
101
102 if (len > limit)
103 len = limit;
104
105 len = af_alg_make_sg(&ctx->sgl, &msg->msg_iter, len);
106 if (len < 0) {
107 err = copied ? 0 : len;
108 goto unlock;
109 }
110
111 ahash_request_set_crypt(&ctx->req, ctx->sgl.sg, NULL, len);
112
113 err = af_alg_wait_for_completion(crypto_ahash_update(&ctx->req),
114 &ctx->completion);
115 af_alg_free_sg(&ctx->sgl);
116 if (err)
117 goto unlock;
118
119 copied += len;
120 iov_iter_advance(&msg->msg_iter, len);
121 }
122
123 err = 0;
124
125 ctx->more = msg->msg_flags & MSG_MORE;
126 if (!ctx->more) {
127 err = hash_alloc_result(sk, ctx);
128 if (err)
129 goto unlock;
130
131 ahash_request_set_crypt(&ctx->req, NULL, ctx->result, 0);
132 err = af_alg_wait_for_completion(crypto_ahash_final(&ctx->req),
133 &ctx->completion);
134 }
135
136unlock:
137 release_sock(sk);
138
139 return err ?: copied;
140}
141
142static ssize_t hash_sendpage(struct socket *sock, struct page *page,
143 int offset, size_t size, int flags)
144{
145 struct sock *sk = sock->sk;
146 struct alg_sock *ask = alg_sk(sk);
147 struct hash_ctx *ctx = ask->private;
148 int err;
149
150 if (flags & MSG_SENDPAGE_NOTLAST)
151 flags |= MSG_MORE;
152
153 lock_sock(sk);
154 sg_init_table(ctx->sgl.sg, 1);
155 sg_set_page(ctx->sgl.sg, page, size, offset);
156
157 if (!(flags & MSG_MORE)) {
158 err = hash_alloc_result(sk, ctx);
159 if (err)
160 goto unlock;
161 } else if (!ctx->more)
162 hash_free_result(sk, ctx);
163
164 ahash_request_set_crypt(&ctx->req, ctx->sgl.sg, ctx->result, size);
165
166 if (!(flags & MSG_MORE)) {
167 if (ctx->more)
168 err = crypto_ahash_finup(&ctx->req);
169 else
170 err = crypto_ahash_digest(&ctx->req);
171 } else {
172 if (!ctx->more) {
173 err = crypto_ahash_init(&ctx->req);
174 err = af_alg_wait_for_completion(err, &ctx->completion);
175 if (err)
176 goto unlock;
177 }
178
179 err = crypto_ahash_update(&ctx->req);
180 }
181
182 err = af_alg_wait_for_completion(err, &ctx->completion);
183 if (err)
184 goto unlock;
185
186 ctx->more = flags & MSG_MORE;
187
188unlock:
189 release_sock(sk);
190
191 return err ?: size;
192}
193
194static int hash_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
195 int flags)
196{
197 struct sock *sk = sock->sk;
198 struct alg_sock *ask = alg_sk(sk);
199 struct hash_ctx *ctx = ask->private;
200 unsigned ds = crypto_ahash_digestsize(crypto_ahash_reqtfm(&ctx->req));
201 bool result;
202 int err;
203
204 if (len > ds)
205 len = ds;
206 else if (len < ds)
207 msg->msg_flags |= MSG_TRUNC;
208
209 lock_sock(sk);
210 result = ctx->result;
211 err = hash_alloc_result(sk, ctx);
212 if (err)
213 goto unlock;
214
215 ahash_request_set_crypt(&ctx->req, NULL, ctx->result, 0);
216
217 if (!result && !ctx->more) {
218 err = af_alg_wait_for_completion(
219 crypto_ahash_init(&ctx->req),
220 &ctx->completion);
221 if (err)
222 goto unlock;
223 }
224
225 if (!result || ctx->more) {
226 ctx->more = 0;
227 err = af_alg_wait_for_completion(crypto_ahash_final(&ctx->req),
228 &ctx->completion);
229 if (err)
230 goto unlock;
231 }
232
233 err = memcpy_to_msg(msg, ctx->result, len);
234
235unlock:
236 hash_free_result(sk, ctx);
237 release_sock(sk);
238
239 return err ?: len;
240}
241
242static int hash_accept(struct socket *sock, struct socket *newsock, int flags)
243{
244 struct sock *sk = sock->sk;
245 struct alg_sock *ask = alg_sk(sk);
246 struct hash_ctx *ctx = ask->private;
247 struct ahash_request *req = &ctx->req;
248 char state[crypto_ahash_statesize(crypto_ahash_reqtfm(req))];
249 struct sock *sk2;
250 struct alg_sock *ask2;
251 struct hash_ctx *ctx2;
252 bool more;
253 int err;
254
255 lock_sock(sk);
256 more = ctx->more;
257 err = more ? crypto_ahash_export(req, state) : 0;
258 release_sock(sk);
259
260 if (err)
261 return err;
262
263 err = af_alg_accept(ask->parent, newsock);
264 if (err)
265 return err;
266
267 sk2 = newsock->sk;
268 ask2 = alg_sk(sk2);
269 ctx2 = ask2->private;
270 ctx2->more = more;
271
272 if (!more)
273 return err;
274
275 err = crypto_ahash_import(&ctx2->req, state);
276 if (err) {
277 sock_orphan(sk2);
278 sock_put(sk2);
279 }
280
281 return err;
282}
283
284static struct proto_ops algif_hash_ops = {
285 .family = PF_ALG,
286
287 .connect = sock_no_connect,
288 .socketpair = sock_no_socketpair,
289 .getname = sock_no_getname,
290 .ioctl = sock_no_ioctl,
291 .listen = sock_no_listen,
292 .shutdown = sock_no_shutdown,
293 .getsockopt = sock_no_getsockopt,
294 .mmap = sock_no_mmap,
295 .bind = sock_no_bind,
296 .setsockopt = sock_no_setsockopt,
297 .poll = sock_no_poll,
298
299 .release = af_alg_release,
300 .sendmsg = hash_sendmsg,
301 .sendpage = hash_sendpage,
302 .recvmsg = hash_recvmsg,
303 .accept = hash_accept,
304};
305
306static int hash_check_key(struct socket *sock)
307{
308 int err = 0;
309 struct sock *psk;
310 struct alg_sock *pask;
311 struct algif_hash_tfm *tfm;
312 struct sock *sk = sock->sk;
313 struct alg_sock *ask = alg_sk(sk);
314
315 lock_sock(sk);
316 if (ask->refcnt)
317 goto unlock_child;
318
319 psk = ask->parent;
320 pask = alg_sk(ask->parent);
321 tfm = pask->private;
322
323 err = -ENOKEY;
324 lock_sock_nested(psk, SINGLE_DEPTH_NESTING);
325 if (!tfm->has_key)
326 goto unlock;
327
328 if (!pask->refcnt++)
329 sock_hold(psk);
330
331 ask->refcnt = 1;
332 sock_put(psk);
333
334 err = 0;
335
336unlock:
337 release_sock(psk);
338unlock_child:
339 release_sock(sk);
340
341 return err;
342}
343
344static int hash_sendmsg_nokey(struct socket *sock, struct msghdr *msg,
345 size_t size)
346{
347 int err;
348
349 err = hash_check_key(sock);
350 if (err)
351 return err;
352
353 return hash_sendmsg(sock, msg, size);
354}
355
356static ssize_t hash_sendpage_nokey(struct socket *sock, struct page *page,
357 int offset, size_t size, int flags)
358{
359 int err;
360
361 err = hash_check_key(sock);
362 if (err)
363 return err;
364
365 return hash_sendpage(sock, page, offset, size, flags);
366}
367
368static int hash_recvmsg_nokey(struct socket *sock, struct msghdr *msg,
369 size_t ignored, int flags)
370{
371 int err;
372
373 err = hash_check_key(sock);
374 if (err)
375 return err;
376
377 return hash_recvmsg(sock, msg, ignored, flags);
378}
379
380static int hash_accept_nokey(struct socket *sock, struct socket *newsock,
381 int flags)
382{
383 int err;
384
385 err = hash_check_key(sock);
386 if (err)
387 return err;
388
389 return hash_accept(sock, newsock, flags);
390}
391
392static struct proto_ops algif_hash_ops_nokey = {
393 .family = PF_ALG,
394
395 .connect = sock_no_connect,
396 .socketpair = sock_no_socketpair,
397 .getname = sock_no_getname,
398 .ioctl = sock_no_ioctl,
399 .listen = sock_no_listen,
400 .shutdown = sock_no_shutdown,
401 .getsockopt = sock_no_getsockopt,
402 .mmap = sock_no_mmap,
403 .bind = sock_no_bind,
404 .setsockopt = sock_no_setsockopt,
405 .poll = sock_no_poll,
406
407 .release = af_alg_release,
408 .sendmsg = hash_sendmsg_nokey,
409 .sendpage = hash_sendpage_nokey,
410 .recvmsg = hash_recvmsg_nokey,
411 .accept = hash_accept_nokey,
412};
413
414static void *hash_bind(const char *name, u32 type, u32 mask)
415{
416 struct algif_hash_tfm *tfm;
417 struct crypto_ahash *hash;
418
419 tfm = kzalloc(sizeof(*tfm), GFP_KERNEL);
420 if (!tfm)
421 return ERR_PTR(-ENOMEM);
422
423 hash = crypto_alloc_ahash(name, type, mask);
424 if (IS_ERR(hash)) {
425 kfree(tfm);
426 return ERR_CAST(hash);
427 }
428
429 tfm->hash = hash;
430
431 return tfm;
432}
433
434static void hash_release(void *private)
435{
436 struct algif_hash_tfm *tfm = private;
437
438 crypto_free_ahash(tfm->hash);
439 kfree(tfm);
440}
441
442static int hash_setkey(void *private, const u8 *key, unsigned int keylen)
443{
444 struct algif_hash_tfm *tfm = private;
445 int err;
446
447 err = crypto_ahash_setkey(tfm->hash, key, keylen);
448 tfm->has_key = !err;
449
450 return err;
451}
452
453static void hash_sock_destruct(struct sock *sk)
454{
455 struct alg_sock *ask = alg_sk(sk);
456 struct hash_ctx *ctx = ask->private;
457
458 hash_free_result(sk, ctx);
459 sock_kfree_s(sk, ctx, ctx->len);
460 af_alg_release_parent(sk);
461}
462
463static int hash_accept_parent_nokey(void *private, struct sock *sk)
464{
465 struct hash_ctx *ctx;
466 struct alg_sock *ask = alg_sk(sk);
467 struct algif_hash_tfm *tfm = private;
468 struct crypto_ahash *hash = tfm->hash;
469 unsigned len = sizeof(*ctx) + crypto_ahash_reqsize(hash);
470
471 ctx = sock_kmalloc(sk, len, GFP_KERNEL);
472 if (!ctx)
473 return -ENOMEM;
474
475 ctx->result = NULL;
476 ctx->len = len;
477 ctx->more = 0;
478 af_alg_init_completion(&ctx->completion);
479
480 ask->private = ctx;
481
482 ahash_request_set_tfm(&ctx->req, hash);
483 ahash_request_set_callback(&ctx->req, CRYPTO_TFM_REQ_MAY_BACKLOG,
484 af_alg_complete, &ctx->completion);
485
486 sk->sk_destruct = hash_sock_destruct;
487
488 return 0;
489}
490
491static int hash_accept_parent(void *private, struct sock *sk)
492{
493 struct algif_hash_tfm *tfm = private;
494
495 if (!tfm->has_key && crypto_ahash_has_setkey(tfm->hash))
496 return -ENOKEY;
497
498 return hash_accept_parent_nokey(private, sk);
499}
500
501static const struct af_alg_type algif_type_hash = {
502 .bind = hash_bind,
503 .release = hash_release,
504 .setkey = hash_setkey,
505 .accept = hash_accept_parent,
506 .accept_nokey = hash_accept_parent_nokey,
507 .ops = &algif_hash_ops,
508 .ops_nokey = &algif_hash_ops_nokey,
509 .name = "hash",
510 .owner = THIS_MODULE
511};
512
513static int __init algif_hash_init(void)
514{
515 return af_alg_register_type(&algif_type_hash);
516}
517
518static void __exit algif_hash_exit(void)
519{
520 int err = af_alg_unregister_type(&algif_type_hash);
521 BUG_ON(err);
522}
523
524module_init(algif_hash_init);
525module_exit(algif_hash_exit);
526MODULE_LICENSE("GPL");
527
