/* * 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 _WIN32 #define _WIN32_WINNT 0x0500 #include <windows.h> #define UUID MYUUID #endif #include <stdio.h> #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> #ifdef HAVE_SYS_TIME_H #include <sys/time.h> #endif #include <sys/wait.h> #include <sys/stat.h> #ifdef HAVE_SYS_FILE_H #include <sys/file.h> #endif #ifdef HAVE_SYS_IOCTL_H #include <sys/ioctl.h> #endif #ifdef HAVE_SYS_SOCKET_H #include <sys/socket.h> #endif #ifdef HAVE_SYS_UN_H #include <sys/un.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 #if defined(__linux__) && defined(HAVE_SYS_SYSCALL_H) #include <sys/syscall.h> #endif #ifdef HAVE_SYS_RESOURCE_H #include <sys/resource.h> #endif #include "uuidP.h" #include "uuidd.h" #ifdef HAVE_SRANDOM #define srand(x) srandom(x) #define rand() random() #endif #ifdef TLS #define THREAD_LOCAL static TLS #else #define THREAD_LOCAL static #endif #if defined(__linux__) && defined(__NR_gettid) && defined(HAVE_JRAND48) #define DO_JRAND_MIX THREAD_LOCAL unsigned short jrand_seed[3]; #endif #ifdef _WIN32 static void gettimeofday (struct timeval *tv, void *dummy) { FILETIME ftime; uint64_t n; GetSystemTimeAsFileTime (&ftime); n = (((uint64_t) ftime.dwHighDateTime << 32) + (uint64_t) ftime.dwLowDateTime); if (n) { n /= 10; n -= ((369 * 365 + 89) * (uint64_t) 86400) * 1000000; } tv->tv_sec = n / 1000000; tv->tv_usec = n % 1000000; } static int getuid (void) { return 1; } #endif static int get_random_fd(void) { struct timeval tv; static int fd = -2; int i; if (fd == -2) { gettimeofday(&tv, 0); #ifndef _WIN32 fd = open("/dev/urandom", O_RDONLY); if (fd == -1) fd = open("/dev/random", O_RDONLY | O_NONBLOCK); if (fd >= 0) { i = fcntl(fd, F_GETFD); if (i >= 0) fcntl(fd, F_SETFD, i | FD_CLOEXEC); } #endif srand((getpid() << 16) ^ getuid() ^ tv.tv_sec ^ tv.tv_usec); #ifdef DO_JRAND_MIX jrand_seed[0] = getpid() ^ (tv.tv_sec & 0xFFFF); jrand_seed[1] = getppid() ^ (tv.tv_usec & 0xFFFF); jrand_seed[2] = (tv.tv_sec ^ tv.tv_usec) >> 16; #endif } /* 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; unsigned short tmp_seed[3]; 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; #ifdef DO_JRAND_MIX memcpy(tmp_seed, jrand_seed, sizeof(tmp_seed)); jrand_seed[2] = jrand_seed[2] ^ syscall(__NR_gettid); for (cp = buf, i = 0; i < nbytes; i++) *cp++ ^= (jrand48(tmp_seed) >> 7) & 0xFF; memcpy(jrand_seed, tmp_seed, sizeof(jrand_seed)-sizeof(unsigned short)); #endif return; } /* * Get the ethernet hardware address, if we can find it... * * XXX for a windows version, probably should use GetAdaptersInfo: * http://www.codeguru.com/cpp/i-n/network/networkinformation/article.php/c5451 * commenting out get_node_id just to get gen_uuid to compile under windows * is not the right way to go! */ 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, int *num) { THREAD_LOCAL int adjustment = 0; THREAD_LOCAL struct timeval last = {0, 0}; THREAD_LOCAL int state_fd = -2; THREAD_LOCAL FILE *state_f; THREAD_LOCAL uint16_t clock_seq; struct timeval tv; struct flock fl; uint64_t clock_reg; mode_t save_umask; int len; if (state_fd == -2) { save_umask = umask(0); state_fd = open("/var/lib/libuuid/clock.txt", O_RDWR|O_CREAT, 0660); (void) umask(save_umask); state_f = fdopen(state_fd, "r+"); if (!state_f) { close(state_fd); state_fd = -1; } } fl.l_type = F_WRLCK; fl.l_whence = SEEK_SET; fl.l_start = 0; fl.l_len = 0; fl.l_pid = 0; if (state_fd >= 0) { rewind(state_f); while (fcntl(state_fd, F_SETLKW, &fl) < 0) { if ((errno == EAGAIN) || (errno == EINTR)) continue; fclose(state_f); close(state_fd); state_fd = -1; break; } } if (state_fd >= 0) { unsigned int cl; unsigned long tv1, tv2; int a; if (fscanf(state_f, "clock: %04x tv: %lu %lu adj: %d\n", &cl, &tv1, &tv2, &a) == 4) { clock_seq = cl & 0x3FFF; last.tv_sec = tv1; last.tv_usec = tv2; adjustment = a; } } if ((last.tv_sec == 0) && (last.tv_usec == 0)) { get_random_bytes(&clock_seq, sizeof(clock_seq)); clock_seq &= 0x3FFF; gettimeofday(&last, 0); last.tv_sec--; } try_again: gettimeofday(&tv, 0); 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 += ((uint64_t) tv.tv_sec)*10000000; clock_reg += (((uint64_t) 0x01B21DD2) << 32) + 0x13814000; if (num && (*num > 1)) { adjustment += *num - 1; last.tv_usec += adjustment / 10; adjustment = adjustment % 10; last.tv_sec += last.tv_usec / 1000000; last.tv_usec = last.tv_usec % 1000000; } if (state_fd > 0) { rewind(state_f); len = fprintf(state_f, "clock: %04x tv: %016lu %08lu adj: %08d\n", clock_seq, last.tv_sec, last.tv_usec, adjustment); fflush(state_f); if (ftruncate(state_fd, len) < 0) { fprintf(state_f, " \n"); fflush(state_f); } rewind(state_f); fl.l_type = F_UNLCK; fcntl(state_fd, F_SETLK, &fl); } *clock_high = clock_reg >> 32; *clock_low = clock_reg; *ret_clock_seq = clock_seq; return 0; } static ssize_t read_all(int fd, char *buf, size_t count) { ssize_t ret; ssize_t c = 0; int tries = 0; memset(buf, 0, count); while (count > 0) { ret = read(fd, buf, count); if (ret <= 0) { if ((errno == EAGAIN || errno == EINTR || ret == 0) && (tries++ < 5)) continue; return c ? c : -1; } if (ret > 0) tries = 0; count -= ret; buf += ret; c += ret; } return c; } /* * Close all file descriptors */ static void close_all_fds(void) { int i, max; #if defined(HAVE_SYSCONF) && defined(_SC_OPEN_MAX) max = sysconf(_SC_OPEN_MAX); #elif defined(HAVE_GETDTABLESIZE) max = getdtablesize(); #elif defined(HAVE_GETRLIMIT) && defined(RLIMIT_NOFILE) struct rlimit rl; getrlimit(RLIMIT_NOFILE, &rl); max = rl.rlim_cur; #else max = OPEN_MAX; #endif for (i=0; i < max; i++) { close(i); if (i <= 2) open("/dev/null", O_RDWR); } } /* * Try using the uuidd daemon to generate the UUID * * Returns 0 on success, non-zero on failure. */ static int get_uuid_via_daemon(int op, uuid_t out, int *num) { #if defined(USE_UUIDD) && defined(HAVE_SYS_UN_H) char op_buf[64]; int op_len; int s; ssize_t ret; int32_t reply_len = 0, expected = 16; struct sockaddr_un srv_addr; struct stat st; pid_t pid; static const char *uuidd_path = UUIDD_PATH; static int access_ret = -2; static int start_attempts = 0; if ((s = socket(AF_UNIX, SOCK_STREAM, 0)) < 0) return -1; srv_addr.sun_family = AF_UNIX; strcpy(srv_addr.sun_path, UUIDD_SOCKET_PATH); if (connect(s, (const struct sockaddr *) &srv_addr, sizeof(struct sockaddr_un)) < 0) { if (access_ret == -2) access_ret = access(uuidd_path, X_OK); if (access_ret == 0) access_ret = stat(uuidd_path, &st); if (access_ret == 0 && (st.st_mode & (S_ISUID | S_ISGID)) == 0) access_ret = access(UUIDD_DIR, W_OK); if (access_ret == 0 && start_attempts++ < 5) { if ((pid = fork()) == 0) { close_all_fds(); execl(uuidd_path, "uuidd", "-qT", "300", (char *) NULL); exit(1); } (void) waitpid(pid, 0, 0); if (connect(s, (const struct sockaddr *) &srv_addr, sizeof(struct sockaddr_un)) < 0) goto fail; } else goto fail; } op_buf[0] = op; op_len = 1; if (op == UUIDD_OP_BULK_TIME_UUID) { memcpy(op_buf+1, num, sizeof(*num)); op_len += sizeof(*num); expected += sizeof(*num); } ret = write(s, op_buf, op_len); if (ret < 1) goto fail; ret = read_all(s, (char *) &reply_len, sizeof(reply_len)); if (ret < 0) goto fail; if (reply_len != expected) goto fail; ret = read_all(s, op_buf, reply_len); if (op == UUIDD_OP_BULK_TIME_UUID) memcpy(op_buf+16, num, sizeof(int)); memcpy(out, op_buf, 16); close(s); return ((ret == expected) ? 0 : -1); fail: close(s); #endif return -1; } void uuid__generate_time(uuid_t out, int *num) { 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, num); 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_time(uuid_t out) { #ifdef TLS THREAD_LOCAL int num = 0; THREAD_LOCAL struct uuid uu; THREAD_LOCAL time_t last_time = 0; time_t now; if (num > 0) { now = time(0); if (now > last_time+1) num = 0; } if (num <= 0) { num = 1000; if (get_uuid_via_daemon(UUIDD_OP_BULK_TIME_UUID, out, &num) == 0) { last_time = time(0); uuid_unpack(out, &uu); num--; return; } num = 0; } if (num > 0) { uu.time_low++; if (uu.time_low == 0) { uu.time_mid++; if (uu.time_mid == 0) uu.time_hi_and_version++; } num--; uuid_pack(&uu, out); return; } #else if (get_uuid_via_daemon(UUIDD_OP_TIME_UUID, out, 0) == 0) return; #endif uuid__generate_time(out, 0); } void uuid__generate_random(uuid_t out, int *num) { uuid_t buf; struct uuid uu; int i, n; if (!num || !*num) n = 1; else n = *num; for (i = 0; i < n; i++) { 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); out += sizeof(uuid_t); } } void uuid_generate_random(uuid_t out) { int num = 1; /* No real reason to use the daemon for random uuid's -- yet */ uuid__generate_random(out, &num); } /* * 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); }