projects / deliverable / linux.git / blame
| Commit | Line | Data |
|---|---|---|
| 14a958e6 FDBM |
1 | /* |
| 2 | * Copyright (C) 2014 Filipe David Borba Manana <fdmanana@gmail.com> | |
| 3 | * | |
| 4 | * This program is free software; you can redistribute it and/or | |
| 5 | * modify it under the terms of the GNU General Public | |
| 6 | * License v2 as published by the Free Software Foundation. | |
| 7 | * | |
| 8 | * This program is distributed in the hope that it will be useful, | |
| 9 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
| 10 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
| 11 | * General Public License for more details. | |
| 12 | */ | |
| 13 | ||
| 14 | #include <crypto/hash.h> | |
| 15 | #include <linux/err.h> | |
| 16 | #include "hash.h" | |
| 17 | ||
| 18 | static struct crypto_shash *tfm; | |
| 19 | ||
| 20 | int __init btrfs_hash_init(void) | |
| 21 | { | |
| 22 | tfm = crypto_alloc_shash("crc32c", 0, 0); | |
| 14a958e6 | 23 | |
| 6f84e236 | 24 | return PTR_ERR_OR_ZERO(tfm); |
| 14a958e6 FDBM |
25 | } |
| 26 | ||
| 27 | void btrfs_hash_exit(void) | |
| 28 | { | |
| 29 | crypto_free_shash(tfm); | |
| 30 | } | |
| 31 | ||
| 32 | u32 btrfs_crc32c(u32 crc, const void *address, unsigned int length) | |
| 33 | { | |
| 34 | struct { | |
| 35 | struct shash_desc shash; | |
| 36 | char ctx[crypto_shash_descsize(tfm)]; | |
| 37 | } desc; | |
| 38 | int err; | |
| 39 | ||
| 40 | desc.shash.tfm = tfm; | |
| 41 | desc.shash.flags = 0; | |
| 42 | *(u32 *)desc.ctx = crc; | |
| 43 | ||
| 44 | err = crypto_shash_update(&desc.shash, address, length); | |
| 45 | BUG_ON(err); | |
| 46 | ||
| 47 | return *(u32 *)desc.ctx; | |
| 48 | } |