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-rw-r--r--e2fsprogs/uuid/gen_uuid.c310
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diff --git a/e2fsprogs/uuid/gen_uuid.c b/e2fsprogs/uuid/gen_uuid.c
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+/*
+ * 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%
+ */
+
+#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 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);
+}