[apple/libc.git] / uuid / uuidsrc / gen_uuid.c

/*
 * 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%
 */

/*
 * Force inclusion of SVID stuff since we need it if we're compiling in
 * gcc-wall wall mode
 */
#define _SVID_SOURCE

#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
#ifdef HAVE_STDLIB_H
#include <stdlib.h>
#endif
#include <string.h>
#include <fcntl.h>
#include <errno.h>
#include <sys/types.h>
#include <sys/time.h>
#include <sys/stat.h>
#include <sys/file.h>
#ifdef HAVE_SYS_IOCTL_H
#include <sys/ioctl.h>
#endif
#ifdef HAVE_SYS_SOCKET_H
#include <sys/socket.h>
#endif
#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 AF_LINK
	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 AF_LINK
		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 /* AF_LINK */
#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);
}
Commit	Line	Data
59e0d9fe A	1	/*
	2	* gen_uuid.c --- generate a DCE-compatible uuid
	3	*
	4	* Copyright (C) 1996, 1997, 1998, 1999 Theodore Ts'o.
	5	*
	6	* %Begin-Header%
	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	* 1. Redistributions of source code must retain the above copyright
	11	* notice, and the entire permission notice in its entirety,
	12	* including the disclaimer of warranties.
	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	* 3. The name of the author may not be used to endorse or promote
	17	* products derived from this software without specific prior
	18	* written permission.
	19	*
	20	* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
	21	* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
	22	* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE, ALL OF
	23	* WHICH ARE HEREBY DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE
	24	* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
	25	* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
	26	* OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
	27	* BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
	28	* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
	29	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
	30	* USE OF THIS SOFTWARE, EVEN IF NOT ADVISED OF THE POSSIBILITY OF SUCH
	31	* DAMAGE.
	32	* %End-Header%
	33	*/
	34
	35	/*
	36	* Force inclusion of SVID stuff since we need it if we're compiling in
	37	* gcc-wall wall mode
	38	*/
	39	#define _SVID_SOURCE
	40
	41	#ifdef HAVE_UNISTD_H
	42	#include <unistd.h>
	43	#endif
	44	#ifdef HAVE_STDLIB_H
	45	#include <stdlib.h>
	46	#endif
	47	#include <string.h>
	48	#include <fcntl.h>
	49	#include <errno.h>
	50	#include <sys/types.h>
	51	#include <sys/time.h>
	52	#include <sys/stat.h>
	53	#include <sys/file.h>
	54	#ifdef HAVE_SYS_IOCTL_H
	55	#include <sys/ioctl.h>
	56	#endif
	57	#ifdef HAVE_SYS_SOCKET_H
	58	#include <sys/socket.h>
	59	#endif
	60	#ifdef HAVE_SYS_SOCKIO_H
	61	#include <sys/sockio.h>
	62	#endif
	63	#ifdef HAVE_NET_IF_H
	64	#include <net/if.h>
65	#endif
66	#ifdef HAVE_NETINET_IN_H
67	#include <netinet/in.h>
68	#endif
69	#ifdef HAVE_NET_IF_DL_H
70	#include <net/if_dl.h>
71	#endif
72
73	#include "uuidP.h"
74
75	#ifdef HAVE_SRANDOM
76	#define srand(x) srandom(x)
77	#define rand() random()
78	#endif
79
80	static int get_random_fd(void)
81	{
82	struct timeval tv;
83	static int fd = -2;
84	int i;
85
86	if (fd == -2) {
87	gettimeofday(&tv, 0);
88	fd = open("/dev/urandom", O_RDONLY);
89	if (fd == -1)
90	fd = open("/dev/random", O_RDONLY \| O_NONBLOCK);
91	srand((getpid() << 16) ^ getuid() ^ tv.tv_sec ^ tv.tv_usec);
92	}
93	/* Crank the random number generator a few times */
94	gettimeofday(&tv, 0);
95	for (i = (tv.tv_sec ^ tv.tv_usec) & 0x1F; i > 0; i--)
96	rand();
97	return fd;
98	}
99
100
101	/*
102	* Generate a series of random bytes. Use /dev/urandom if possible,
103	* and if not, use srandom/random.
104	*/
105	static void get_random_bytes(void *buf, int nbytes)
106	{
107	int i, n = nbytes, fd = get_random_fd();
108	int lose_counter = 0;
109	unsigned char cp = (unsigned char ) buf;
110
111	if (fd >= 0) {
112	while (n > 0) {
113	i = read(fd, cp, n);
114	if (i <= 0) {
115	if (lose_counter++ > 16)
116	break;
117	continue;
118	}
119	n -= i;
120	cp += i;
121	lose_counter = 0;
122	}
123	}
124
125	/*
126	* We do this all the time, but this is the only source of
127	* randomness if /dev/random/urandom is out to lunch.
128	*/
129	for (cp = buf, i = 0; i < nbytes; i++)
130	*cp++ ^= (rand() >> 7) & 0xFF;
131	return;
132	}
133
134	/*
135	* Get the ethernet hardware address, if we can find it...
136	*/
137	static int get_node_id(unsigned char *node_id)
138	{
139	#ifdef HAVE_NET_IF_H
140	int sd;
141	struct ifreq ifr, *ifrp;
142	struct ifconf ifc;
143	char buf[1024];
144	int n, i;
145	unsigned char *a;
146	#ifdef AF_LINK
147	struct sockaddr_dl *sdlp;
148	#endif
149
150	/*
151	* BSD 4.4 defines the size of an ifreq to be
152	* max(sizeof(ifreq), sizeof(ifreq.ifr_name)+ifreq.ifr_addr.sa_len
153	* However, under earlier systems, sa_len isn't present, so the size is
154	* just sizeof(struct ifreq)
155	*/
156	#ifdef HAVE_SA_LEN
157	#ifndef max
158	#define max(a,b) ((a) > (b) ? (a) : (b))
159	#endif
160	#define ifreq_size(i) max(sizeof(struct ifreq),\
161	sizeof((i).ifr_name)+(i).ifr_addr.sa_len)
162	#else
163	#define ifreq_size(i) sizeof(struct ifreq)
164	#endif /* HAVE_SA_LEN*/
165
166	sd = socket(AF_INET, SOCK_DGRAM, IPPROTO_IP);
167	if (sd < 0) {
168	return -1;
169	}
170	memset(buf, 0, sizeof(buf));
171	ifc.ifc_len = sizeof(buf);
172	ifc.ifc_buf = buf;
173	if (ioctl (sd, SIOCGIFCONF, (char *)&ifc) < 0) {
174	close(sd);
175	return -1;
176	}
177	n = ifc.ifc_len;
178	for (i = 0; i < n; i+= ifreq_size(*ifrp) ) {
179	ifrp = (struct ifreq )((char ) ifc.ifc_buf+i);
180	strncpy(ifr.ifr_name, ifrp->ifr_name, IFNAMSIZ);
181	#ifdef SIOCGIFHWADDR
182	if (ioctl(sd, SIOCGIFHWADDR, &ifr) < 0)
183	continue;
184	a = (unsigned char *) &ifr.ifr_hwaddr.sa_data;
185	#else
186	#ifdef SIOCGENADDR
187	if (ioctl(sd, SIOCGENADDR, &ifr) < 0)
188	continue;
189	a = (unsigned char *) ifr.ifr_enaddr;
190	#else
191	#ifdef AF_LINK
192	sdlp = (struct sockaddr_dl *) &ifrp->ifr_addr;
193	if ((sdlp->sdl_family != AF_LINK) \|\| (sdlp->sdl_alen != 6))
194	continue;
195	a = (unsigned char *) &sdlp->sdl_data[sdlp->sdl_nlen];
196	#else
197	/*
198	* XXX we don't have a way of getting the hardware
199	* address
200	*/
201	close(sd);
202	return 0;
203	#endif /* AF_LINK */
204	#endif /* SIOCGENADDR */
205	#endif /* SIOCGIFHWADDR */
206	if (!a[0] && !a[1] && !a[2] && !a[3] && !a[4] && !a[5])
207	continue;
208	if (node_id) {
209	memcpy(node_id, a, 6);
210	close(sd);
211	return 1;
212	}
213	}
214	close(sd);
215	#endif
216	return 0;
217	}
218
219	/* Assume that the gettimeofday() has microsecond granularity */
220	#define MAX_ADJUSTMENT 10
221
222	static int get_clock(uint32_t clock_high, uint32_t clock_low, uint16_t *ret_clock_seq)
223	{
224	static int adjustment = 0;
225	static struct timeval last = {0, 0};
226	static uint16_t clock_seq;
227	struct timeval tv;
228	unsigned long long clock_reg;
229
230	try_again:
231	gettimeofday(&tv, 0);
232	if ((last.tv_sec == 0) && (last.tv_usec == 0)) {
233	get_random_bytes(&clock_seq, sizeof(clock_seq));
234	clock_seq &= 0x3FFF;
235	last = tv;
236	last.tv_sec--;
237	}
238	if ((tv.tv_sec < last.tv_sec) \|\|
239	((tv.tv_sec == last.tv_sec) &&
240	(tv.tv_usec < last.tv_usec))) {
241	clock_seq = (clock_seq+1) & 0x3FFF;
242	adjustment = 0;
243	last = tv;
244	} else if ((tv.tv_sec == last.tv_sec) &&
245	(tv.tv_usec == last.tv_usec)) {
246	if (adjustment >= MAX_ADJUSTMENT)
247	goto try_again;
248	adjustment++;
249	} else {
250	adjustment = 0;
251	last = tv;
252	}
253
254	clock_reg = tv.tv_usec*10 + adjustment;
255	clock_reg += ((unsigned long long) tv.tv_sec)*10000000;
256	clock_reg += (((unsigned long long) 0x01B21DD2) << 32) + 0x13814000;
257
258	*clock_high = clock_reg >> 32;
259	*clock_low = clock_reg;
260	*ret_clock_seq = clock_seq;
261	return 0;
262	}
263
264	void uuid_generate_time(uuid_t out)
265	{
266	static unsigned char node_id[6];
267	static int has_init = 0;
268	struct uuid uu;
269	uint32_t clock_mid;
270
271	if (!has_init) {
272	if (get_node_id(node_id) <= 0) {
273	get_random_bytes(node_id, 6);
274	/*
275	* Set multicast bit, to prevent conflicts
276	* with IEEE 802 addresses obtained from
277	* network cards
278	*/
279	node_id[0] \|= 0x01;
280	}
281	has_init = 1;
282	}
283	get_clock(&clock_mid, &uu.time_low, &uu.clock_seq);
284	uu.clock_seq \|= 0x8000;
285	uu.time_mid = (uint16_t) clock_mid;
286	uu.time_hi_and_version = ((clock_mid >> 16) & 0x0FFF) \| 0x1000;
287	memcpy(uu.node, node_id, 6);
288	uuid_pack(&uu, out);
289	}
290
291	void uuid_generate_random(uuid_t out)
292	{
293	uuid_t buf;
294	struct uuid uu;
295
296	get_random_bytes(buf, sizeof(buf));
297	uuid_unpack(buf, &uu);
298
299	uu.clock_seq = (uu.clock_seq & 0x3FFF) \| 0x8000;
300	uu.time_hi_and_version = (uu.time_hi_and_version & 0x0FFF) \| 0x4000;
301	uuid_pack(&uu, out);
302	}
303
304	/*
305	* This is the generic front-end to uuid_generate_random and
306	* uuid_generate_time. It uses uuid_generate_random only if
307	* /dev/urandom is available, since otherwise we won't have
308	* high-quality randomness.
309	*/
310	void uuid_generate(uuid_t out)
311	{
312	if (get_random_fd() >= 0)
313	uuid_generate_random(out);
314	else
315	uuid_generate_time(out);
316	}