diff options
Diffstat (limited to 'lib/uuid.c')
| -rw-r--r-- | lib/uuid.c | 124 |
1 files changed, 105 insertions, 19 deletions
diff --git a/lib/uuid.c b/lib/uuid.c index 398821e4dce1..e309b4c5be3d 100644 --- a/lib/uuid.c +++ b/lib/uuid.c @@ -1,47 +1,133 @@ +// SPDX-License-Identifier: GPL-2.0-only /* * Unified UUID/GUID definition * - * Copyright (C) 2009, Intel Corp. + * Copyright (C) 2009, 2016 Intel Corp. * Huang Ying <ying.huang@intel.com> - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public License version - * 2 as published by the Free Software Foundation; - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program; if not, write to the Free Software - * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ #include <linux/kernel.h> +#include <linux/ctype.h> +#include <linux/errno.h> #include <linux/export.h> #include <linux/uuid.h> #include <linux/random.h> +const guid_t guid_null; +EXPORT_SYMBOL(guid_null); +const uuid_t uuid_null; +EXPORT_SYMBOL(uuid_null); + +const u8 guid_index[16] = {3,2,1,0,5,4,7,6,8,9,10,11,12,13,14,15}; +const u8 uuid_index[16] = {0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15}; + +/** + * generate_random_uuid - generate a random UUID + * @uuid: where to put the generated UUID + * + * Random UUID interface + * + * Used to create a Boot ID or a filesystem UUID/GUID, but can be + * useful for other kernel drivers. + */ +void generate_random_uuid(unsigned char uuid[16]) +{ + get_random_bytes(uuid, 16); + /* Set UUID version to 4 --- truly random generation */ + uuid[6] = (uuid[6] & 0x0F) | 0x40; + /* Set the UUID variant to DCE */ + uuid[8] = (uuid[8] & 0x3F) | 0x80; +} +EXPORT_SYMBOL(generate_random_uuid); + +void generate_random_guid(unsigned char guid[16]) +{ + get_random_bytes(guid, 16); + /* Set GUID version to 4 --- truly random generation */ + guid[7] = (guid[7] & 0x0F) | 0x40; + /* Set the GUID variant to DCE */ + guid[8] = (guid[8] & 0x3F) | 0x80; +} +EXPORT_SYMBOL(generate_random_guid); + static void __uuid_gen_common(__u8 b[16]) { - prandom_bytes(b, 16); + get_random_bytes(b, 16); /* reversion 0b10 */ b[8] = (b[8] & 0x3F) | 0x80; } -void uuid_le_gen(uuid_le *lu) +void guid_gen(guid_t *lu) { __uuid_gen_common(lu->b); /* version 4 : random generation */ lu->b[7] = (lu->b[7] & 0x0F) | 0x40; } -EXPORT_SYMBOL_GPL(uuid_le_gen); +EXPORT_SYMBOL_GPL(guid_gen); -void uuid_be_gen(uuid_be *bu) +void uuid_gen(uuid_t *bu) { __uuid_gen_common(bu->b); /* version 4 : random generation */ bu->b[6] = (bu->b[6] & 0x0F) | 0x40; } -EXPORT_SYMBOL_GPL(uuid_be_gen); +EXPORT_SYMBOL_GPL(uuid_gen); + +/** + * uuid_is_valid - checks if a UUID string is valid + * @uuid: UUID string to check + * + * Description: + * It checks if the UUID string is following the format: + * xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx + * + * where x is a hex digit. + * + * Return: true if input is valid UUID string. + */ +bool uuid_is_valid(const char *uuid) +{ + unsigned int i; + + for (i = 0; i < UUID_STRING_LEN; i++) { + if (i == 8 || i == 13 || i == 18 || i == 23) { + if (uuid[i] != '-') + return false; + } else if (!isxdigit(uuid[i])) { + return false; + } + } + + return true; +} +EXPORT_SYMBOL(uuid_is_valid); + +static int __uuid_parse(const char *uuid, __u8 b[16], const u8 ei[16]) +{ + static const u8 si[16] = {0,2,4,6,9,11,14,16,19,21,24,26,28,30,32,34}; + unsigned int i; + + if (!uuid_is_valid(uuid)) + return -EINVAL; + + for (i = 0; i < 16; i++) { + int hi = hex_to_bin(uuid[si[i] + 0]); + int lo = hex_to_bin(uuid[si[i] + 1]); + + b[ei[i]] = (hi << 4) | lo; + } + + return 0; +} + +int guid_parse(const char *uuid, guid_t *u) +{ + return __uuid_parse(uuid, u->b, guid_index); +} +EXPORT_SYMBOL(guid_parse); + +int uuid_parse(const char *uuid, uuid_t *u) +{ + return __uuid_parse(uuid, u->b, uuid_index); +} +EXPORT_SYMBOL(uuid_parse); |