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 int limit = ALG_MAX_PAGES * PAGE_SIZE;
67 struct sock *sk = sock->sk;
68 struct alg_sock *ask = alg_sk(sk);
69 struct hash_ctx *ctx = ask->private;
73 if (limit > sk->sk_sndbuf)
74 limit = sk->sk_sndbuf;
78 if ((msg->msg_flags & MSG_MORE))
79 hash_free_result(sk, ctx);
81 err = crypto_wait_req(crypto_ahash_init(&ctx->req), &ctx->wait);
88 while (msg_data_left(msg)) {
89 int len = msg_data_left(msg);
94 ctx->sgl.sgt.sgl = ctx->sgl.sgl;
95 ctx->sgl.sgt.nents = 0;
96 ctx->sgl.sgt.orig_nents = 0;
98 len = extract_iter_to_sg(&msg->msg_iter, len, &ctx->sgl.sgt,
101 err = copied ? 0 : len;
104 sg_mark_end(ctx->sgl.sgt.sgl + ctx->sgl.sgt.nents);
106 ctx->sgl.need_unpin = iov_iter_extract_will_pin(&msg->msg_iter);
108 ahash_request_set_crypt(&ctx->req, ctx->sgl.sgt.sgl, NULL, len);
110 err = crypto_wait_req(crypto_ahash_update(&ctx->req),
112 af_alg_free_sg(&ctx->sgl);
114 iov_iter_revert(&msg->msg_iter, len);
123 ctx->more = msg->msg_flags & MSG_MORE;
125 err = hash_alloc_result(sk, ctx);
129 ahash_request_set_crypt(&ctx->req, NULL, ctx->result, 0);
130 err = crypto_wait_req(crypto_ahash_final(&ctx->req),
137 return err ?: copied;
140 static ssize_t hash_sendpage(struct socket *sock, struct page *page,
141 int offset, size_t size, int flags)
143 struct sock *sk = sock->sk;
144 struct alg_sock *ask = alg_sk(sk);
145 struct hash_ctx *ctx = ask->private;
148 if (flags & MSG_SENDPAGE_NOTLAST)
152 sg_init_table(ctx->sgl.sgl, 1);
153 sg_set_page(ctx->sgl.sgl, page, size, offset);
155 if (!(flags & MSG_MORE)) {
156 err = hash_alloc_result(sk, ctx);
159 } else if (!ctx->more)
160 hash_free_result(sk, ctx);
162 ahash_request_set_crypt(&ctx->req, ctx->sgl.sgl, ctx->result, size);
164 if (!(flags & MSG_MORE)) {
166 err = crypto_ahash_finup(&ctx->req);
168 err = crypto_ahash_digest(&ctx->req);
171 err = crypto_ahash_init(&ctx->req);
172 err = crypto_wait_req(err, &ctx->wait);
177 err = crypto_ahash_update(&ctx->req);
180 err = crypto_wait_req(err, &ctx->wait);
184 ctx->more = flags & MSG_MORE;
192 static int hash_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
195 struct sock *sk = sock->sk;
196 struct alg_sock *ask = alg_sk(sk);
197 struct hash_ctx *ctx = ask->private;
198 unsigned ds = crypto_ahash_digestsize(crypto_ahash_reqtfm(&ctx->req));
205 msg->msg_flags |= MSG_TRUNC;
208 result = ctx->result;
209 err = hash_alloc_result(sk, ctx);
213 ahash_request_set_crypt(&ctx->req, NULL, ctx->result, 0);
215 if (!result && !ctx->more) {
216 err = crypto_wait_req(crypto_ahash_init(&ctx->req),
222 if (!result || ctx->more) {
224 err = crypto_wait_req(crypto_ahash_final(&ctx->req),
230 err = memcpy_to_msg(msg, ctx->result, len);
233 hash_free_result(sk, ctx);
239 static int hash_accept(struct socket *sock, struct socket *newsock, int flags,
242 struct sock *sk = sock->sk;
243 struct alg_sock *ask = alg_sk(sk);
244 struct hash_ctx *ctx = ask->private;
245 struct ahash_request *req = &ctx->req;
246 struct crypto_ahash *tfm;
248 struct alg_sock *ask2;
249 struct hash_ctx *ctx2;
254 tfm = crypto_ahash_reqtfm(req);
255 state = kmalloc(crypto_ahash_statesize(tfm), GFP_KERNEL);
262 err = more ? crypto_ahash_export(req, state) : 0;
268 err = af_alg_accept(ask->parent, newsock, kern);
274 ctx2 = ask2->private;
280 err = crypto_ahash_import(&ctx2->req, state);
287 kfree_sensitive(state);
293 static struct proto_ops algif_hash_ops = {
296 .connect = sock_no_connect,
297 .socketpair = sock_no_socketpair,
298 .getname = sock_no_getname,
299 .ioctl = sock_no_ioctl,
300 .listen = sock_no_listen,
301 .shutdown = sock_no_shutdown,
302 .mmap = sock_no_mmap,
303 .bind = sock_no_bind,
305 .release = af_alg_release,
306 .sendmsg = hash_sendmsg,
307 .sendpage = hash_sendpage,
308 .recvmsg = hash_recvmsg,
309 .accept = hash_accept,
312 static int hash_check_key(struct socket *sock)
316 struct alg_sock *pask;
317 struct crypto_ahash *tfm;
318 struct sock *sk = sock->sk;
319 struct alg_sock *ask = alg_sk(sk);
322 if (!atomic_read(&ask->nokey_refcnt))
326 pask = alg_sk(ask->parent);
330 lock_sock_nested(psk, SINGLE_DEPTH_NESTING);
331 if (crypto_ahash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
334 atomic_dec(&pask->nokey_refcnt);
335 atomic_set(&ask->nokey_refcnt, 0);
347 static int hash_sendmsg_nokey(struct socket *sock, struct msghdr *msg,
352 err = hash_check_key(sock);
356 return hash_sendmsg(sock, msg, size);
359 static ssize_t hash_sendpage_nokey(struct socket *sock, struct page *page,
360 int offset, size_t size, int flags)
364 err = hash_check_key(sock);
368 return hash_sendpage(sock, page, offset, size, flags);
371 static int hash_recvmsg_nokey(struct socket *sock, struct msghdr *msg,
372 size_t ignored, int flags)
376 err = hash_check_key(sock);
380 return hash_recvmsg(sock, msg, ignored, flags);
383 static int hash_accept_nokey(struct socket *sock, struct socket *newsock,
384 int flags, bool kern)
388 err = hash_check_key(sock);
392 return hash_accept(sock, newsock, flags, kern);
395 static struct proto_ops algif_hash_ops_nokey = {
398 .connect = sock_no_connect,
399 .socketpair = sock_no_socketpair,
400 .getname = sock_no_getname,
401 .ioctl = sock_no_ioctl,
402 .listen = sock_no_listen,
403 .shutdown = sock_no_shutdown,
404 .mmap = sock_no_mmap,
405 .bind = sock_no_bind,
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,
414 static void *hash_bind(const char *name, u32 type, u32 mask)
416 return crypto_alloc_ahash(name, type, mask);
419 static void hash_release(void *private)
421 crypto_free_ahash(private);
424 static int hash_setkey(void *private, const u8 *key, unsigned int keylen)
426 return crypto_ahash_setkey(private, key, keylen);
429 static void hash_sock_destruct(struct sock *sk)
431 struct alg_sock *ask = alg_sk(sk);
432 struct hash_ctx *ctx = ask->private;
434 hash_free_result(sk, ctx);
435 sock_kfree_s(sk, ctx, ctx->len);
436 af_alg_release_parent(sk);
439 static int hash_accept_parent_nokey(void *private, struct sock *sk)
441 struct crypto_ahash *tfm = private;
442 struct alg_sock *ask = alg_sk(sk);
443 struct hash_ctx *ctx;
444 unsigned int len = sizeof(*ctx) + crypto_ahash_reqsize(tfm);
446 ctx = sock_kmalloc(sk, len, GFP_KERNEL);
453 crypto_init_wait(&ctx->wait);
457 ahash_request_set_tfm(&ctx->req, tfm);
458 ahash_request_set_callback(&ctx->req, CRYPTO_TFM_REQ_MAY_BACKLOG,
459 crypto_req_done, &ctx->wait);
461 sk->sk_destruct = hash_sock_destruct;
466 static int hash_accept_parent(void *private, struct sock *sk)
468 struct crypto_ahash *tfm = private;
470 if (crypto_ahash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
473 return hash_accept_parent_nokey(private, sk);
476 static const struct af_alg_type algif_type_hash = {
478 .release = hash_release,
479 .setkey = hash_setkey,
480 .accept = hash_accept_parent,
481 .accept_nokey = hash_accept_parent_nokey,
482 .ops = &algif_hash_ops,
483 .ops_nokey = &algif_hash_ops_nokey,
488 static int __init algif_hash_init(void)
490 return af_alg_register_type(&algif_type_hash);
493 static void __exit algif_hash_exit(void)
495 int err = af_alg_unregister_type(&algif_type_hash);
499 module_init(algif_hash_init);
500 module_exit(algif_hash_exit);
501 MODULE_LICENSE("GPL");