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1/*
2 * Unified UUID/GUID definition
3 *
4 * Copyright (C) 2009, Intel Corp.
5 * Huang Ying <ying.huang@intel.com>
6 *
7 * This program is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License version
9 * 2 as published by the Free Software Foundation;
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
19 */
20
21#include <linux/kernel.h>
22#include <linux/export.h>
23#include <linux/uuid.h>
24#include <linux/random.h>
25
26static void __uuid_gen_common(__u8 b[16])
27{
28 prandom_bytes(b, 16);
29 /* reversion 0b10 */
30 b[8] = (b[8] & 0x3F) | 0x80;
31}
32
33void uuid_le_gen(uuid_le *lu)
34{
35 __uuid_gen_common(lu->b);
36 /* version 4 : random generation */
37 lu->b[7] = (lu->b[7] & 0x0F) | 0x40;
38}
39EXPORT_SYMBOL_GPL(uuid_le_gen);
40
41void uuid_be_gen(uuid_be *bu)
42{
43 __uuid_gen_common(bu->b);
44 /* version 4 : random generation */
45 bu->b[6] = (bu->b[6] & 0x0F) | 0x40;
46}
47EXPORT_SYMBOL_GPL(uuid_be_gen);
1/*
2 * Unified UUID/GUID definition
3 *
4 * Copyright (C) 2009, 2016 Intel Corp.
5 * Huang Ying <ying.huang@intel.com>
6 *
7 * This program is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License version
9 * 2 as published by the Free Software Foundation;
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 */
16
17#include <linux/kernel.h>
18#include <linux/ctype.h>
19#include <linux/errno.h>
20#include <linux/export.h>
21#include <linux/uuid.h>
22#include <linux/random.h>
23
24const u8 uuid_le_index[16] = {3,2,1,0,5,4,7,6,8,9,10,11,12,13,14,15};
25EXPORT_SYMBOL(uuid_le_index);
26const u8 uuid_be_index[16] = {0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15};
27EXPORT_SYMBOL(uuid_be_index);
28
29/***************************************************************
30 * Random UUID interface
31 *
32 * Used here for a Boot ID, but can be useful for other kernel
33 * drivers.
34 ***************************************************************/
35
36/*
37 * Generate random UUID
38 */
39void generate_random_uuid(unsigned char uuid[16])
40{
41 get_random_bytes(uuid, 16);
42 /* Set UUID version to 4 --- truly random generation */
43 uuid[6] = (uuid[6] & 0x0F) | 0x40;
44 /* Set the UUID variant to DCE */
45 uuid[8] = (uuid[8] & 0x3F) | 0x80;
46}
47EXPORT_SYMBOL(generate_random_uuid);
48
49static void __uuid_gen_common(__u8 b[16])
50{
51 prandom_bytes(b, 16);
52 /* reversion 0b10 */
53 b[8] = (b[8] & 0x3F) | 0x80;
54}
55
56void uuid_le_gen(uuid_le *lu)
57{
58 __uuid_gen_common(lu->b);
59 /* version 4 : random generation */
60 lu->b[7] = (lu->b[7] & 0x0F) | 0x40;
61}
62EXPORT_SYMBOL_GPL(uuid_le_gen);
63
64void uuid_be_gen(uuid_be *bu)
65{
66 __uuid_gen_common(bu->b);
67 /* version 4 : random generation */
68 bu->b[6] = (bu->b[6] & 0x0F) | 0x40;
69}
70EXPORT_SYMBOL_GPL(uuid_be_gen);
71
72/**
73 * uuid_is_valid - checks if UUID string valid
74 * @uuid: UUID string to check
75 *
76 * Description:
77 * It checks if the UUID string is following the format:
78 * xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx
79 * where x is a hex digit.
80 *
81 * Return: true if input is valid UUID string.
82 */
83bool uuid_is_valid(const char *uuid)
84{
85 unsigned int i;
86
87 for (i = 0; i < UUID_STRING_LEN; i++) {
88 if (i == 8 || i == 13 || i == 18 || i == 23) {
89 if (uuid[i] != '-')
90 return false;
91 } else if (!isxdigit(uuid[i])) {
92 return false;
93 }
94 }
95
96 return true;
97}
98EXPORT_SYMBOL(uuid_is_valid);
99
100static int __uuid_to_bin(const char *uuid, __u8 b[16], const u8 ei[16])
101{
102 static const u8 si[16] = {0,2,4,6,9,11,14,16,19,21,24,26,28,30,32,34};
103 unsigned int i;
104
105 if (!uuid_is_valid(uuid))
106 return -EINVAL;
107
108 for (i = 0; i < 16; i++) {
109 int hi = hex_to_bin(uuid[si[i] + 0]);
110 int lo = hex_to_bin(uuid[si[i] + 1]);
111
112 b[ei[i]] = (hi << 4) | lo;
113 }
114
115 return 0;
116}
117
118int uuid_le_to_bin(const char *uuid, uuid_le *u)
119{
120 return __uuid_to_bin(uuid, u->b, uuid_le_index);
121}
122EXPORT_SYMBOL(uuid_le_to_bin);
123
124int uuid_be_to_bin(const char *uuid, uuid_be *u)
125{
126 return __uuid_to_bin(uuid, u->b, uuid_be_index);
127}
128EXPORT_SYMBOL(uuid_be_to_bin);