old_e2fsprogs/uuid/gen_uuid.c

/* vi: set sw=4 ts=4: */
/*
 * gen_uuid.c --- generate a DCE-compatible uuid
 *
 * Copyright (C) 1996, 1997, 1998, 1999 Theodore Ts'o.
 *
 * %Begin-Header%
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, and the entire permission notice in its entirety,
 *    including the disclaimer of warranties.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. The name of the author may not be used to endorse or promote
 *    products derived from this software without specific prior
 *    written permission.
 *
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE, ALL OF
 * WHICH ARE HEREBY DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
 * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
 * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
 * USE OF THIS SOFTWARE, EVEN IF NOT ADVISED OF THE POSSIBILITY OF SUCH
 * DAMAGE.
 * %End-Header%
 */

#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <fcntl.h>
#include <errno.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/file.h>
#include <sys/time.h>
#ifdef HAVE_SYS_IOCTL_H
#include <sys/ioctl.h>
#endif
#include <sys/socket.h>
#ifdef HAVE_SYS_SOCKIO_H
#include <sys/sockio.h>
#endif
#ifdef HAVE_NET_IF_H
#include <net/if.h>
#endif
#ifdef HAVE_NETINET_IN_H
#include <netinet/in.h>
#endif
#ifdef HAVE_NET_IF_DL_H
#include <net/if_dl.h>
#endif

#include "uuidP.h"

#ifdef HAVE_SRANDOM
#define srand(x)	srandom(x)
#define rand()		random()
#endif

static int get_random_fd(void)
{
	struct timeval	tv;
	static int	fd = -2;
	int		i;

	if (fd == -2) {
		gettimeofday(&tv, 0);
		fd = open("/dev/urandom", O_RDONLY);
		if (fd == -1)
			fd = open("/dev/random", O_RDONLY | O_NONBLOCK);
		srand((getpid() << 16) ^ getuid() ^ tv.tv_sec ^ tv.tv_usec);
	}
	/* Crank the random number generator a few times */
	gettimeofday(&tv, 0);
	for (i = (tv.tv_sec ^ tv.tv_usec) & 0x1F; i > 0; i--)
		rand();
	return fd;
}


/*
 * Generate a series of random bytes.  Use /dev/urandom if possible,
 * and if not, use srandom/random.
 */
static void get_random_bytes(void *buf, int nbytes)
{
	int i, n = nbytes, fd = get_random_fd();
	int lose_counter = 0;
	unsigned char *cp = (unsigned char *) buf;

	if (fd >= 0) {
		while (n > 0) {
			i = read(fd, cp, n);
			if (i <= 0) {
				if (lose_counter++ > 16)
					break;
				continue;
			}
			n -= i;
			cp += i;
			lose_counter = 0;
		}
	}

	/*
	 * We do this all the time, but this is the only source of
	 * randomness if /dev/random/urandom is out to lunch.
	 */
	for (cp = buf, i = 0; i < nbytes; i++)
		*cp++ ^= (rand() >> 7) & 0xFF;
	return;
}

/*
 * Get the ethernet hardware address, if we can find it...
 */
static int get_node_id(unsigned char *node_id)
{
#ifdef HAVE_NET_IF_H
	int		sd;
	struct ifreq	ifr, *ifrp;
	struct ifconf	ifc;
	char buf[1024];
	int		n, i;
	unsigned char	*a;
#ifdef HAVE_NET_IF_DL_H
	struct sockaddr_dl *sdlp;
#endif

/*
 * BSD 4.4 defines the size of an ifreq to be
 * max(sizeof(ifreq), sizeof(ifreq.ifr_name)+ifreq.ifr_addr.sa_len
 * However, under earlier systems, sa_len isn't present, so the size is
 * just sizeof(struct ifreq)
 */
#ifdef HAVE_SA_LEN
#ifndef max
#define max(a,b) ((a) > (b) ? (a) : (b))
#endif
#define ifreq_size(i) max(sizeof(struct ifreq),\
     sizeof((i).ifr_name)+(i).ifr_addr.sa_len)
#else
#define ifreq_size(i) sizeof(struct ifreq)
#endif /* HAVE_SA_LEN*/

	sd = socket(AF_INET, SOCK_DGRAM, IPPROTO_IP);
	if (sd < 0) {
		return -1;
	}
	memset(buf, 0, sizeof(buf));
	ifc.ifc_len = sizeof(buf);
	ifc.ifc_buf = buf;
	if (ioctl (sd, SIOCGIFCONF, (char *)&ifc) < 0) {
		close(sd);
		return -1;
	}
	n = ifc.ifc_len;
	for (i = 0; i < n; i+= ifreq_size(*ifrp) ) {
		ifrp = (struct ifreq *)((char *) ifc.ifc_buf+i);
		strncpy(ifr.ifr_name, ifrp->ifr_name, IFNAMSIZ);
#ifdef SIOCGIFHWADDR
		if (ioctl(sd, SIOCGIFHWADDR, &ifr) < 0)
			continue;
		a = (unsigned char *) &ifr.ifr_hwaddr.sa_data;
#else
#ifdef SIOCGENADDR
		if (ioctl(sd, SIOCGENADDR, &ifr) < 0)
			continue;
		a = (unsigned char *) ifr.ifr_enaddr;
#else
#ifdef HAVE_NET_IF_DL_H
		sdlp = (struct sockaddr_dl *) &ifrp->ifr_addr;
		if ((sdlp->sdl_family != AF_LINK) || (sdlp->sdl_alen != 6))
			continue;
		a = (unsigned char *) &sdlp->sdl_data[sdlp->sdl_nlen];
#else
		/*
		 * XXX we don't have a way of getting the hardware
		 * address
		 */
		close(sd);
		return 0;
#endif /* HAVE_NET_IF_DL_H */
#endif /* SIOCGENADDR */
#endif /* SIOCGIFHWADDR */
		if (!a[0] && !a[1] && !a[2] && !a[3] && !a[4] && !a[5])
			continue;
		if (node_id) {
			memcpy(node_id, a, 6);
			close(sd);
			return 1;
		}
	}
	close(sd);
#endif
	return 0;
}

/* Assume that the gettimeofday() has microsecond granularity */
#define MAX_ADJUSTMENT 10

static int get_clock(uint32_t *clock_high, uint32_t *clock_low, uint16_t *ret_clock_seq)
{
	static int			adjustment = 0;
	static struct timeval		last = {0, 0};
	static uint16_t			clock_seq;
	struct timeval			tv;
	unsigned long long		clock_reg;

try_again:
	gettimeofday(&tv, 0);
	if ((last.tv_sec == 0) && (last.tv_usec == 0)) {
		get_random_bytes(&clock_seq, sizeof(clock_seq));
		clock_seq &= 0x3FFF;
		last = tv;
		last.tv_sec--;
	}
	if ((tv.tv_sec < last.tv_sec) ||
	    ((tv.tv_sec == last.tv_sec) &&
	     (tv.tv_usec < last.tv_usec))) {
		clock_seq = (clock_seq+1) & 0x3FFF;
		adjustment = 0;
		last = tv;
	} else if ((tv.tv_sec == last.tv_sec) &&
	    (tv.tv_usec == last.tv_usec)) {
		if (adjustment >= MAX_ADJUSTMENT)
			goto try_again;
		adjustment++;
	} else {
		adjustment = 0;
		last = tv;
	}

	clock_reg = tv.tv_usec*10 + adjustment;
	clock_reg += ((unsigned long long) tv.tv_sec)*10000000;
	clock_reg += (((unsigned long long) 0x01B21DD2) << 32) + 0x13814000;

	*clock_high = clock_reg >> 32;
	*clock_low = clock_reg;
	*ret_clock_seq = clock_seq;
	return 0;
}

void uuid_generate_time(uuid_t out)
{
	static unsigned char node_id[6];
	static int has_init = 0;
	struct uuid uu;
	uint32_t	clock_mid;

	if (!has_init) {
		if (get_node_id(node_id) <= 0) {
			get_random_bytes(node_id, 6);
			/*
			 * Set multicast bit, to prevent conflicts
			 * with IEEE 802 addresses obtained from
			 * network cards
			 */
			node_id[0] |= 0x01;
		}
		has_init = 1;
	}
	get_clock(&clock_mid, &uu.time_low, &uu.clock_seq);
	uu.clock_seq |= 0x8000;
	uu.time_mid = (uint16_t) clock_mid;
	uu.time_hi_and_version = ((clock_mid >> 16) & 0x0FFF) | 0x1000;
	memcpy(uu.node, node_id, 6);
	uuid_pack(&uu, out);
}

void uuid_generate_random(uuid_t out)
{
	uuid_t	buf;
	struct uuid uu;

	get_random_bytes(buf, sizeof(buf));
	uuid_unpack(buf, &uu);

	uu.clock_seq = (uu.clock_seq & 0x3FFF) | 0x8000;
	uu.time_hi_and_version = (uu.time_hi_and_version & 0x0FFF) | 0x4000;
	uuid_pack(&uu, out);
}

/*
 * This is the generic front-end to uuid_generate_random and
 * uuid_generate_time.  It uses uuid_generate_random only if
 * /dev/urandom is available, since otherwise we won't have
 * high-quality randomness.
 */
void uuid_generate(uuid_t out)
{
	if (get_random_fd() >= 0)
		uuid_generate_random(out);
	else
		uuid_generate_time(out);
}
1	/* vi: set sw=4 ts=4: */
2	/*
3	* gen_uuid.c --- generate a DCE-compatible uuid
4	*
5	* Copyright (C) 1996, 1997, 1998, 1999 Theodore Ts'o.
6	*
7	* %Begin-Header%
8	* Redistribution and use in source and binary forms, with or without
9	* modification, are permitted provided that the following conditions
10	* are met:
11	* 1. Redistributions of source code must retain the above copyright
12	* notice, and the entire permission notice in its entirety,
13	* including the disclaimer of warranties.
14	* 2. Redistributions in binary form must reproduce the above copyright
15	* notice, this list of conditions and the following disclaimer in the
16	* documentation and/or other materials provided with the distribution.
17	* 3. The name of the author may not be used to endorse or promote
18	* products derived from this software without specific prior
19	* written permission.
20	*
21	* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
22	* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
23	* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE, ALL OF
24	* WHICH ARE HEREBY DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE
25	* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
26	* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
27	* OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
28	* BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
29	* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
30	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
31	* USE OF THIS SOFTWARE, EVEN IF NOT ADVISED OF THE POSSIBILITY OF SUCH
32	* DAMAGE.
33	* %End-Header%
34	*/
35
36	#include <unistd.h>
37	#include <stdlib.h>
38	#include <string.h>
39	#include <fcntl.h>
40	#include <errno.h>
41	#include <sys/types.h>
42	#include <sys/stat.h>
43	#include <sys/file.h>
44	#include <sys/time.h>
45	#ifdef HAVE_SYS_IOCTL_H
46	#include <sys/ioctl.h>
47	#endif
48	#include <sys/socket.h>
49	#ifdef HAVE_SYS_SOCKIO_H
50	#include <sys/sockio.h>
51	#endif
52	#ifdef HAVE_NET_IF_H
53	#include <net/if.h>
54	#endif
55	#ifdef HAVE_NETINET_IN_H
56	#include <netinet/in.h>
57	#endif
58	#ifdef HAVE_NET_IF_DL_H
59	#include <net/if_dl.h>
60	#endif
61
62	#include "uuidP.h"
63
64	#ifdef HAVE_SRANDOM
65	#define srand(x) srandom(x)
66	#define rand() random()
67	#endif
68
69	static int get_random_fd(void)
70	{
71	struct timeval tv;
72	static int fd = -2;
73	int i;
74
75	if (fd == -2) {
76	gettimeofday(&tv, 0);
77	fd = open("/dev/urandom", O_RDONLY);
78	if (fd == -1)
79	fd = open("/dev/random", O_RDONLY \| O_NONBLOCK);
80	srand((getpid() << 16) ^ getuid() ^ tv.tv_sec ^ tv.tv_usec);
81	}
82	/* Crank the random number generator a few times */
83	gettimeofday(&tv, 0);
84	for (i = (tv.tv_sec ^ tv.tv_usec) & 0x1F; i > 0; i--)
85	rand();
86	return fd;
87	}
88
89
90	/*
91	* Generate a series of random bytes. Use /dev/urandom if possible,
92	* and if not, use srandom/random.
93	*/
94	static void get_random_bytes(void *buf, int nbytes)
95	{
96	int i, n = nbytes, fd = get_random_fd();
97	int lose_counter = 0;
98	unsigned char cp = (unsigned char ) buf;
99
100	if (fd >= 0) {
101	while (n > 0) {
102	i = read(fd, cp, n);
103	if (i <= 0) {
104	if (lose_counter++ > 16)
105	break;
106	continue;
107	}
108	n -= i;
109	cp += i;
110	lose_counter = 0;
111	}
112	}
113
114	/*
115	* We do this all the time, but this is the only source of
116	* randomness if /dev/random/urandom is out to lunch.
117	*/
118	for (cp = buf, i = 0; i < nbytes; i++)
119	*cp++ ^= (rand() >> 7) & 0xFF;
120	return;
121	}
122
123	/*
124	* Get the ethernet hardware address, if we can find it...
125	*/
126	static int get_node_id(unsigned char *node_id)
127	{
128	#ifdef HAVE_NET_IF_H
129	int sd;
130	struct ifreq ifr, *ifrp;
131	struct ifconf ifc;
132	char buf[1024];
133	int n, i;
134	unsigned char *a;
135	#ifdef HAVE_NET_IF_DL_H
136	struct sockaddr_dl *sdlp;
137	#endif
138
139	/*
140	* BSD 4.4 defines the size of an ifreq to be
141	* max(sizeof(ifreq), sizeof(ifreq.ifr_name)+ifreq.ifr_addr.sa_len
142	* However, under earlier systems, sa_len isn't present, so the size is
143	* just sizeof(struct ifreq)
144	*/
145	#ifdef HAVE_SA_LEN
146	#ifndef max
147	#define max(a,b) ((a) > (b) ? (a) : (b))
148	#endif
149	#define ifreq_size(i) max(sizeof(struct ifreq),\
150	sizeof((i).ifr_name)+(i).ifr_addr.sa_len)
151	#else
152	#define ifreq_size(i) sizeof(struct ifreq)
153	#endif /* HAVE_SA_LEN*/
154
155	sd = socket(AF_INET, SOCK_DGRAM, IPPROTO_IP);
156	if (sd < 0) {
157	return -1;
158	}
159	memset(buf, 0, sizeof(buf));
160	ifc.ifc_len = sizeof(buf);
161	ifc.ifc_buf = buf;
162	if (ioctl (sd, SIOCGIFCONF, (char *)&ifc) < 0) {
163	close(sd);
164	return -1;
165	}
166	n = ifc.ifc_len;
167	for (i = 0; i < n; i+= ifreq_size(*ifrp) ) {
168	ifrp = (struct ifreq )((char ) ifc.ifc_buf+i);
169	strncpy(ifr.ifr_name, ifrp->ifr_name, IFNAMSIZ);
170	#ifdef SIOCGIFHWADDR
171	if (ioctl(sd, SIOCGIFHWADDR, &ifr) < 0)
172	continue;
173	a = (unsigned char *) &ifr.ifr_hwaddr.sa_data;
174	#else
175	#ifdef SIOCGENADDR
176	if (ioctl(sd, SIOCGENADDR, &ifr) < 0)
177	continue;
178	a = (unsigned char *) ifr.ifr_enaddr;
179	#else
180	#ifdef HAVE_NET_IF_DL_H
181	sdlp = (struct sockaddr_dl *) &ifrp->ifr_addr;
182	if ((sdlp->sdl_family != AF_LINK) \|\| (sdlp->sdl_alen != 6))
183	continue;
184	a = (unsigned char *) &sdlp->sdl_data[sdlp->sdl_nlen];
185	#else
186	/*
187	* XXX we don't have a way of getting the hardware
188	* address
189	*/
190	close(sd);
191	return 0;
192	#endif /* HAVE_NET_IF_DL_H */
193	#endif /* SIOCGENADDR */
194	#endif /* SIOCGIFHWADDR */
195	if (!a[0] && !a[1] && !a[2] && !a[3] && !a[4] && !a[5])
196	continue;
197	if (node_id) {
198	memcpy(node_id, a, 6);
199	close(sd);
200	return 1;
201	}
202	}
203	close(sd);
204	#endif
205	return 0;
206	}
207
208	/* Assume that the gettimeofday() has microsecond granularity */
209	#define MAX_ADJUSTMENT 10
210
211	static int get_clock(uint32_t clock_high, uint32_t clock_low, uint16_t *ret_clock_seq)
212	{
213	static int adjustment = 0;
214	static struct timeval last = {0, 0};
215	static uint16_t clock_seq;
216	struct timeval tv;
217	unsigned long long clock_reg;
218
219	try_again:
220	gettimeofday(&tv, 0);
221	if ((last.tv_sec == 0) && (last.tv_usec == 0)) {
222	get_random_bytes(&clock_seq, sizeof(clock_seq));
223	clock_seq &= 0x3FFF;
224	last = tv;
225	last.tv_sec--;
226	}
227	if ((tv.tv_sec < last.tv_sec) \|\|
228	((tv.tv_sec == last.tv_sec) &&
229	(tv.tv_usec < last.tv_usec))) {
230	clock_seq = (clock_seq+1) & 0x3FFF;
231	adjustment = 0;
232	last = tv;
233	} else if ((tv.tv_sec == last.tv_sec) &&
234	(tv.tv_usec == last.tv_usec)) {
235	if (adjustment >= MAX_ADJUSTMENT)
236	goto try_again;
237	adjustment++;
238	} else {
239	adjustment = 0;
240	last = tv;
241	}
242
243	clock_reg = tv.tv_usec*10 + adjustment;
244	clock_reg += ((unsigned long long) tv.tv_sec)*10000000;
245	clock_reg += (((unsigned long long) 0x01B21DD2) << 32) + 0x13814000;
246
247	*clock_high = clock_reg >> 32;
248	*clock_low = clock_reg;
249	*ret_clock_seq = clock_seq;
250	return 0;
251	}
252
253	void uuid_generate_time(uuid_t out)
254	{
255	static unsigned char node_id[6];
256	static int has_init = 0;
257	struct uuid uu;
258	uint32_t clock_mid;
259
260	if (!has_init) {
261	if (get_node_id(node_id) <= 0) {
262	get_random_bytes(node_id, 6);
263	/*
264	* Set multicast bit, to prevent conflicts
265	* with IEEE 802 addresses obtained from
266	* network cards
267	*/
268	node_id[0] \|= 0x01;
269	}
270	has_init = 1;
271	}
272	get_clock(&clock_mid, &uu.time_low, &uu.clock_seq);
273	uu.clock_seq \|= 0x8000;
274	uu.time_mid = (uint16_t) clock_mid;
275	uu.time_hi_and_version = ((clock_mid >> 16) & 0x0FFF) \| 0x1000;
276	memcpy(uu.node, node_id, 6);
277	uuid_pack(&uu, out);
278	}
279
280	void uuid_generate_random(uuid_t out)
281	{
282	uuid_t buf;
283	struct uuid uu;
284
285	get_random_bytes(buf, sizeof(buf));
286	uuid_unpack(buf, &uu);
287
288	uu.clock_seq = (uu.clock_seq & 0x3FFF) \| 0x8000;
289	uu.time_hi_and_version = (uu.time_hi_and_version & 0x0FFF) \| 0x4000;
290	uuid_pack(&uu, out);
291	}
292
293	/*
294	* This is the generic front-end to uuid_generate_random and
295	* uuid_generate_time. It uses uuid_generate_random only if
296	* /dev/urandom is available, since otherwise we won't have
297	* high-quality randomness.
298	*/
299	void uuid_generate(uuid_t out)
300	{
301	if (get_random_fd() >= 0)
302	uuid_generate_random(out);
303	else
304	uuid_generate_time(out);
305	}