1 // SPDX-License-Identifier: GPL-2.0-or-later
3 * algif_hash: User-space interface for hash algorithms
5 * This file provides the user-space API for hash algorithms.
7 * Copyright (c) 2010 Herbert Xu <herbert@gondor.apana.org.au>
10 #include <crypto/hash.h>
11 #include <crypto/if_alg.h>
12 #include <linux/init.h>
13 #include <linux/kernel.h>
15 #include <linux/module.h>
16 #include <linux/net.h>
20 struct af_alg_sgl sgl;
24 struct crypto_wait wait;
29 struct ahash_request req;
32 static int hash_alloc_result(struct sock *sk, struct hash_ctx *ctx)
39 ds = crypto_ahash_digestsize(crypto_ahash_reqtfm(&ctx->req));
41 ctx->result = sock_kmalloc(sk, ds, GFP_KERNEL);
45 memset(ctx->result, 0, ds);
50 static void hash_free_result(struct sock *sk, struct hash_ctx *ctx)
57 ds = crypto_ahash_digestsize(crypto_ahash_reqtfm(&ctx->req));
59 sock_kzfree_s(sk, ctx->result, ds);
63 static int hash_sendmsg(struct socket *sock, struct msghdr *msg,
66 struct sock *sk = sock->sk;
67 struct alg_sock *ask = alg_sk(sk);
68 struct hash_ctx *ctx = ask->private;
70 size_t len, max_pages, npages;
71 bool continuing = ctx->more, need_init = false;
74 max_pages = min_t(size_t, ALG_MAX_PAGES,
75 DIV_ROUND_UP(sk->sk_sndbuf, PAGE_SIZE));
79 if ((msg->msg_flags & MSG_MORE))
80 hash_free_result(sk, ctx);
86 while (msg_data_left(msg)) {
87 ctx->sgl.sgt.sgl = ctx->sgl.sgl;
88 ctx->sgl.sgt.nents = 0;
89 ctx->sgl.sgt.orig_nents = 0;
92 npages = iov_iter_npages(&msg->msg_iter, max_pages);
96 if (npages > ARRAY_SIZE(ctx->sgl.sgl)) {
99 kvmalloc(array_size(npages,
100 sizeof(*ctx->sgl.sgt.sgl)),
102 if (!ctx->sgl.sgt.sgl)
105 sg_init_table(ctx->sgl.sgl, npages);
107 ctx->sgl.need_unpin = iov_iter_extract_will_pin(&msg->msg_iter);
109 err = extract_iter_to_sg(&msg->msg_iter, LONG_MAX,
110 &ctx->sgl.sgt, npages, 0);
114 sg_mark_end(ctx->sgl.sgt.sgl + ctx->sgl.sgt.nents - 1);
116 if (!msg_data_left(msg)) {
117 err = hash_alloc_result(sk, ctx);
122 ahash_request_set_crypt(&ctx->req, ctx->sgl.sgt.sgl,
125 if (!msg_data_left(msg) && !continuing &&
126 !(msg->msg_flags & MSG_MORE)) {
127 err = crypto_ahash_digest(&ctx->req);
130 err = crypto_wait_req(
131 crypto_ahash_init(&ctx->req),
138 if (msg_data_left(msg) || (msg->msg_flags & MSG_MORE))
139 err = crypto_ahash_update(&ctx->req);
141 err = crypto_ahash_finup(&ctx->req);
145 err = crypto_wait_req(err, &ctx->wait);
150 af_alg_free_sg(&ctx->sgl);
153 ctx->more = msg->msg_flags & MSG_MORE;
157 return copied ?: err;
160 af_alg_free_sg(&ctx->sgl);
164 static ssize_t hash_sendpage(struct socket *sock, struct page *page,
165 int offset, size_t size, int flags)
167 struct sock *sk = sock->sk;
168 struct alg_sock *ask = alg_sk(sk);
169 struct hash_ctx *ctx = ask->private;
172 if (flags & MSG_SENDPAGE_NOTLAST)
176 sg_init_table(ctx->sgl.sgl, 1);
177 sg_set_page(ctx->sgl.sgl, page, size, offset);
179 if (!(flags & MSG_MORE)) {
180 err = hash_alloc_result(sk, ctx);
183 } else if (!ctx->more)
184 hash_free_result(sk, ctx);
186 ahash_request_set_crypt(&ctx->req, ctx->sgl.sgl, ctx->result, size);
188 if (!(flags & MSG_MORE)) {
190 err = crypto_ahash_finup(&ctx->req);
192 err = crypto_ahash_digest(&ctx->req);
195 err = crypto_ahash_init(&ctx->req);
196 err = crypto_wait_req(err, &ctx->wait);
201 err = crypto_ahash_update(&ctx->req);
204 err = crypto_wait_req(err, &ctx->wait);
208 ctx->more = flags & MSG_MORE;
216 static int hash_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
219 struct sock *sk = sock->sk;
220 struct alg_sock *ask = alg_sk(sk);
221 struct hash_ctx *ctx = ask->private;
222 unsigned ds = crypto_ahash_digestsize(crypto_ahash_reqtfm(&ctx->req));
229 msg->msg_flags |= MSG_TRUNC;
232 result = ctx->result;
233 err = hash_alloc_result(sk, ctx);
237 ahash_request_set_crypt(&ctx->req, NULL, ctx->result, 0);
239 if (!result && !ctx->more) {
240 err = crypto_wait_req(crypto_ahash_init(&ctx->req),
246 if (!result || ctx->more) {
248 err = crypto_wait_req(crypto_ahash_final(&ctx->req),
254 err = memcpy_to_msg(msg, ctx->result, len);
257 hash_free_result(sk, ctx);
263 static int hash_accept(struct socket *sock, struct socket *newsock, int flags,
266 struct sock *sk = sock->sk;
267 struct alg_sock *ask = alg_sk(sk);
268 struct hash_ctx *ctx = ask->private;
269 struct ahash_request *req = &ctx->req;
270 struct crypto_ahash *tfm;
272 struct alg_sock *ask2;
273 struct hash_ctx *ctx2;
278 tfm = crypto_ahash_reqtfm(req);
279 state = kmalloc(crypto_ahash_statesize(tfm), GFP_KERNEL);
286 err = more ? crypto_ahash_export(req, state) : 0;
292 err = af_alg_accept(ask->parent, newsock, kern);
298 ctx2 = ask2->private;
304 err = crypto_ahash_import(&ctx2->req, state);
311 kfree_sensitive(state);
317 static struct proto_ops algif_hash_ops = {
320 .connect = sock_no_connect,
321 .socketpair = sock_no_socketpair,
322 .getname = sock_no_getname,
323 .ioctl = sock_no_ioctl,
324 .listen = sock_no_listen,
325 .shutdown = sock_no_shutdown,
326 .mmap = sock_no_mmap,
327 .bind = sock_no_bind,
329 .release = af_alg_release,
330 .sendmsg = hash_sendmsg,
331 .sendpage = hash_sendpage,
332 .recvmsg = hash_recvmsg,
333 .accept = hash_accept,
336 static int hash_check_key(struct socket *sock)
340 struct alg_sock *pask;
341 struct crypto_ahash *tfm;
342 struct sock *sk = sock->sk;
343 struct alg_sock *ask = alg_sk(sk);
346 if (!atomic_read(&ask->nokey_refcnt))
350 pask = alg_sk(ask->parent);
354 lock_sock_nested(psk, SINGLE_DEPTH_NESTING);
355 if (crypto_ahash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
358 atomic_dec(&pask->nokey_refcnt);
359 atomic_set(&ask->nokey_refcnt, 0);
371 static int hash_sendmsg_nokey(struct socket *sock, struct msghdr *msg,
376 err = hash_check_key(sock);
380 return hash_sendmsg(sock, msg, size);
383 static ssize_t hash_sendpage_nokey(struct socket *sock, struct page *page,
384 int offset, size_t size, int flags)
388 err = hash_check_key(sock);
392 return hash_sendpage(sock, page, offset, size, flags);
395 static int hash_recvmsg_nokey(struct socket *sock, struct msghdr *msg,
396 size_t ignored, int flags)
400 err = hash_check_key(sock);
404 return hash_recvmsg(sock, msg, ignored, flags);
407 static int hash_accept_nokey(struct socket *sock, struct socket *newsock,
408 int flags, bool kern)
412 err = hash_check_key(sock);
416 return hash_accept(sock, newsock, flags, kern);
419 static struct proto_ops algif_hash_ops_nokey = {
422 .connect = sock_no_connect,
423 .socketpair = sock_no_socketpair,
424 .getname = sock_no_getname,
425 .ioctl = sock_no_ioctl,
426 .listen = sock_no_listen,
427 .shutdown = sock_no_shutdown,
428 .mmap = sock_no_mmap,
429 .bind = sock_no_bind,
431 .release = af_alg_release,
432 .sendmsg = hash_sendmsg_nokey,
433 .sendpage = hash_sendpage_nokey,
434 .recvmsg = hash_recvmsg_nokey,
435 .accept = hash_accept_nokey,
438 static void *hash_bind(const char *name, u32 type, u32 mask)
440 return crypto_alloc_ahash(name, type, mask);
443 static void hash_release(void *private)
445 crypto_free_ahash(private);
448 static int hash_setkey(void *private, const u8 *key, unsigned int keylen)
450 return crypto_ahash_setkey(private, key, keylen);
453 static void hash_sock_destruct(struct sock *sk)
455 struct alg_sock *ask = alg_sk(sk);
456 struct hash_ctx *ctx = ask->private;
458 hash_free_result(sk, ctx);
459 sock_kfree_s(sk, ctx, ctx->len);
460 af_alg_release_parent(sk);
463 static int hash_accept_parent_nokey(void *private, struct sock *sk)
465 struct crypto_ahash *tfm = private;
466 struct alg_sock *ask = alg_sk(sk);
467 struct hash_ctx *ctx;
468 unsigned int len = sizeof(*ctx) + crypto_ahash_reqsize(tfm);
470 ctx = sock_kmalloc(sk, len, GFP_KERNEL);
477 crypto_init_wait(&ctx->wait);
481 ahash_request_set_tfm(&ctx->req, tfm);
482 ahash_request_set_callback(&ctx->req, CRYPTO_TFM_REQ_MAY_BACKLOG,
483 crypto_req_done, &ctx->wait);
485 sk->sk_destruct = hash_sock_destruct;
490 static int hash_accept_parent(void *private, struct sock *sk)
492 struct crypto_ahash *tfm = private;
494 if (crypto_ahash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
497 return hash_accept_parent_nokey(private, sk);
500 static const struct af_alg_type algif_type_hash = {
502 .release = hash_release,
503 .setkey = hash_setkey,
504 .accept = hash_accept_parent,
505 .accept_nokey = hash_accept_parent_nokey,
506 .ops = &algif_hash_ops,
507 .ops_nokey = &algif_hash_ops_nokey,
512 static int __init algif_hash_init(void)
514 return af_alg_register_type(&algif_type_hash);
517 static void __exit algif_hash_exit(void)
519 int err = af_alg_unregister_type(&algif_type_hash);
523 module_init(algif_hash_init);
524 module_exit(algif_hash_exit);
525 MODULE_LICENSE("GPL");