1 /*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21
22 /*
23 * Copyright 2008 Sun Microsystems, Inc. All rights reserved.
24 * Use is subject to license terms.
25 * Copyright (c) 2015, Joyent, Inc.
26 */
27
28 /*
29 * The copyright in this file is taken from the original Leach
30 * & Salz UUID specification, from which this implementation
31 * is derived.
32 */
33
34 /*
35 * Copyright (c) 1990- 1993, 1996 Open Software Foundation, Inc.
36 * Copyright (c) 1989 by Hewlett-Packard Company, Palo Alto, Ca. &
37 * Digital Equipment Corporation, Maynard, Mass. Copyright (c) 1998
38 * Microsoft. To anyone who acknowledges that this file is provided
39 * "AS IS" without any express or implied warranty: permission to use,
40 * copy, modify, and distribute this file for any purpose is hereby
41 * granted without fee, provided that the above copyright notices and
42 * this notice appears in all source code copies, and that none of the
43 * names of Open Software Foundation, Inc., Hewlett-Packard Company,
44 * or Digital Equipment Corporation be used in advertising or
45 * publicity pertaining to distribution of the software without
46 * specific, written prior permission. Neither Open Software
47 * Foundation, Inc., Hewlett-Packard Company, Microsoft, nor Digital
48 * Equipment Corporation makes any representations about the
49 * suitability of this software for any purpose.
50 */
51
52 #include <uuid/uuid.h>
53 #include <stdlib.h>
54 #include <strings.h>
55 #include "uuid_misc.h"
56
57 #define UUCMP(u1, u2) if (u1 != u2) return ((u1 < u2) ? -1 : 1)
58 #define UUIDS_PER_TOD_CALL 10 /* tv_usec is multiplied by 10 */
59
60 void struct_to_string(uuid_t, struct uuid *);
61 void string_to_struct(struct uuid *, uuid_t);
62 void get_system_time(uuid_time_t *);
63
64 /*
65 * Name: get_current_time
66 *
67 * Description: get-current_time -- get time as 60 bit 100ns ticks
68 * since the beginning of unix time.
69 * Compensate for the fact that real clock resolution is
70 * less than 100ns.
71 *
72 * Returns: None.
73 *
74 */
75 void
get_current_time(uuid_time_t * timestamp)76 get_current_time(uuid_time_t *timestamp)
77 {
78 uuid_time_t time_now;
79 static uuid_time_t time_last = 0;
80 static uint16_t uuids_this_tick = 0;
81 int done;
82
83 done = 0;
84 while (!done) {
85 get_system_time(&time_now);
86
87 /*
88 * if clock reading changed since last UUID generated...
89 */
90 if (time_last != time_now) {
91 /*
92 * reset count of uuids generated with
93 * this clock reading
94 */
95 uuids_this_tick = 0;
96 done = 1;
97 } else {
98 uuids_this_tick++;
99 if (uuids_this_tick < UUIDS_PER_TOD_CALL)
100 done = 1;
101 }
102 /*
103 * too many UUIDs for this gettimeofday call; spin
104 */
105 }
106 time_last = time_now;
107 /*
108 * add the count of uuids to low order bits of the clock reading
109 */
110 *timestamp = time_now + uuids_this_tick;
111 }
112
113 /*
114 * Name: get_random
115 *
116 * Description: Gets a random number.
117 *
118 * Returns: nbytes of random information.
119 *
120 */
121 uint16_t
get_random(void)122 get_random(void)
123 {
124 return (arc4random_uniform(UINT16_MAX));
125 }
126
127 /*
128 * Name: uuid_compare
129 *
130 * Description: Compares 2 uuid strings
131 *
132 * Returns: -1 if u1 < u2, 1 if u1 > u2 and 0 if both are equal
133 */
134 int
uuid_compare(uuid_t uu1,uuid_t uu2)135 uuid_compare(uuid_t uu1, uuid_t uu2)
136 {
137
138 struct uuid uuid1, uuid2;
139
140 string_to_struct(&uuid1, uu1);
141 string_to_struct(&uuid2, uu2);
142 UUCMP(uuid1.time_low, uuid2.time_low);
143 UUCMP(uuid1.time_mid, uuid2.time_mid);
144 UUCMP(uuid1.time_hi_and_version, uuid2.time_hi_and_version);
145 UUCMP(uuid1.clock_seq_hi_and_reserved, uuid2.clock_seq_hi_and_reserved);
146 UUCMP(uuid1.clock_seq_low, uuid2.clock_seq_low);
147 return (memcmp(uuid1.node_addr, uuid2.node_addr, 6));
148 }
149
150 /*
151 * Name: get_system_time
152 *
153 * Description: system dependent call to get the current system time.
154 * Returned as 100ns ticks since Oct 15, 1582, but
155 * resolution may be less than 100ns.
156 *
157 * Returns: None
158 */
159 void
get_system_time(uuid_time_t * uuid_time)160 get_system_time(uuid_time_t *uuid_time)
161 {
162 struct timeval tp;
163
164 (void) gettimeofday(&tp, (struct timezone *)0);
165
166 /*
167 * Offset between UUID formatted times and Unix formatted times.
168 * UUID UTC base time is October 15, 1582.
169 * Unix base time is January 1, 1970.
170 */
171 *uuid_time = (uint64_t)tp.tv_sec * 10000000;
172 *uuid_time += tp.tv_usec * 10;
173 *uuid_time += 0x01B21DD213814000ULL;
174 }
175