132 lines
3.0 KiB
C
132 lines
3.0 KiB
C
/*
|
|
* Unified UUID/GUID definition
|
|
*
|
|
* 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.
|
|
*/
|
|
|
|
#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);
|
|
|
|
static void __uuid_gen_common(__u8 b[16])
|
|
{
|
|
prandom_bytes(b, 16);
|
|
/* reversion 0b10 */
|
|
b[8] = (b[8] & 0x3F) | 0x80;
|
|
}
|
|
|
|
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(guid_gen);
|
|
|
|
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_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);
|