1/*	$NetBSD: kern_uuid.c,v 1.19 2014/10/04 11:15:44 riastradh Exp $	*/
2
3/*
4 * Copyright (c) 2002 Marcel Moolenaar
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 *
11 * 1. Redistributions of source code must retain the above copyright
12 *    notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 *    notice, this list of conditions and the following disclaimer in the
15 *    documentation and/or other materials provided with the distribution.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 *
28 * $FreeBSD: /repoman/r/ncvs/src/sys/kern/kern_uuid.c,v 1.7 2004/01/12 13:34:11 rse Exp $
29 */
30
31#include <sys/cdefs.h>
32__KERNEL_RCSID(0, "$NetBSD: kern_uuid.c,v 1.19 2014/10/04 11:15:44 riastradh Exp $");
33
34#include <sys/param.h>
35#include <sys/cprng.h>
36#include <sys/endian.h>
37#include <sys/syscallargs.h>
38#include <sys/systm.h>
39#include <sys/uuid.h>
40
41/*
42 * See also:
43 *	http://www.opengroup.org/dce/info/draft-leach-uuids-guids-01.txt
44 *	http://www.opengroup.org/onlinepubs/009629399/apdxa.htm
45 */
46
47CTASSERT(sizeof(struct uuid) == 16);
48
49static void
50uuid_generate(struct uuid *uuid)
51{
52
53	/* Randomly generate the content.  */
54	cprng_fast(uuid, sizeof(*uuid));
55
56	/* Set the version number to 4.  */
57	uuid->time_hi_and_version &= ~(uint32_t)0xf000;
58	uuid->time_hi_and_version |= 0x4000;
59
60	/* Fix the reserved bits.  */
61	uuid->clock_seq_hi_and_reserved &= ~(uint8_t)0x40;
62	uuid->clock_seq_hi_and_reserved |= 0x80;
63}
64
65int
66sys_uuidgen(struct lwp *l, const struct sys_uuidgen_args *uap, register_t *retval)
67{
68	struct uuid *store, tmp;
69	unsigned count;
70	int error;
71
72	/*
73	 * Limit the number of UUIDs that can be created at the same time
74	 * to some arbitrary number. This isn't really necessary, but I
75	 * like to have some sort of upper-bound that's less than 2G :-)
76	 * XXX needs to be tunable.
77	 */
78	if (SCARG(uap,count) < 1 || SCARG(uap,count) > 2048)
79		return (EINVAL);
80
81	for (store = SCARG(uap,store), count = SCARG(uap,count);
82	     count > 0;
83	     store++, count--) {
84		uuid_generate(&tmp);
85		error = copyout(&tmp, store, sizeof tmp);
86		if (error)
87			return error;
88	}
89
90	return 0;
91}
92
93int
94uuidgen(struct uuid *store, int count)
95{
96
97	while (--count > 0)
98		uuid_generate(store++);
99	return 0;
100}
101
102int
103uuid_snprintf(char *buf, size_t sz, const struct uuid *uuid)
104{
105
106	return snprintf(buf, sz,
107	    "%08x-%04x-%04x-%02x%02x-%02x%02x%02x%02x%02x%02x",
108	    uuid->time_low, uuid->time_mid, uuid->time_hi_and_version,
109	    uuid->clock_seq_hi_and_reserved, uuid->clock_seq_low,
110	    uuid->node[0], uuid->node[1], uuid->node[2], uuid->node[3],
111	    uuid->node[4], uuid->node[5]);
112}
113
114int
115uuid_printf(const struct uuid *uuid)
116{
117	char buf[UUID_STR_LEN];
118
119	(void) uuid_snprintf(buf, sizeof(buf), uuid);
120	printf("%s", buf);
121	return (0);
122}
123
124/*
125 * Encode/Decode UUID into octet-stream.
126 *   http://www.opengroup.org/dce/info/draft-leach-uuids-guids-01.txt
127 *
128 * 0                   1                   2                   3
129 *   0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
130 *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
131 *  |                          time_low                             |
132 *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
133 *  |       time_mid                |         time_hi_and_version   |
134 *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
135 *  |clk_seq_hi_res |  clk_seq_low  |         node (0-1)            |
136 *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
137 *  |                         node (2-5)                            |
138 *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
139 */
140
141void
142uuid_enc_le(void *buf, const struct uuid *uuid)
143{
144	uint8_t *p = buf;
145	int i;
146
147	le32enc(p, uuid->time_low);
148	le16enc(p + 4, uuid->time_mid);
149	le16enc(p + 6, uuid->time_hi_and_version);
150	p[8] = uuid->clock_seq_hi_and_reserved;
151	p[9] = uuid->clock_seq_low;
152	for (i = 0; i < _UUID_NODE_LEN; i++)
153		p[10 + i] = uuid->node[i];
154}
155
156void
157uuid_dec_le(void const *buf, struct uuid *uuid)
158{
159	const uint8_t *p = buf;
160	int i;
161
162	uuid->time_low = le32dec(p);
163	uuid->time_mid = le16dec(p + 4);
164	uuid->time_hi_and_version = le16dec(p + 6);
165	uuid->clock_seq_hi_and_reserved = p[8];
166	uuid->clock_seq_low = p[9];
167	for (i = 0; i < _UUID_NODE_LEN; i++)
168		uuid->node[i] = p[10 + i];
169}
170
171void
172uuid_enc_be(void *buf, const struct uuid *uuid)
173{
174	uint8_t *p = buf;
175	int i;
176
177	be32enc(p, uuid->time_low);
178	be16enc(p + 4, uuid->time_mid);
179	be16enc(p + 6, uuid->time_hi_and_version);
180	p[8] = uuid->clock_seq_hi_and_reserved;
181	p[9] = uuid->clock_seq_low;
182	for (i = 0; i < _UUID_NODE_LEN; i++)
183		p[10 + i] = uuid->node[i];
184}
185
186void
187uuid_dec_be(void const *buf, struct uuid *uuid)
188{
189	const uint8_t *p = buf;
190	int i;
191
192	uuid->time_low = be32dec(p);
193	uuid->time_mid = be16dec(p + 4);
194	uuid->time_hi_and_version = be16dec(p + 6);
195	uuid->clock_seq_hi_and_reserved = p[8];
196	uuid->clock_seq_low = p[9];
197	for (i = 0; i < _UUID_NODE_LEN; i++)
198		uuid->node[i] = p[10 + i];
199}
200