/* 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% */ /* * Force inclusion of SVID stuff since we need it if we're compiling in * gcc-wall wall mode */ #define _SVID_SOURCE #include #ifdef HAVE_UNISTD_H #include #endif #ifdef HAVE_STDLIB_H #include #endif #include #include #include #include #include #include #ifdef HAVE_SYS_FILE_H #include #endif #if HAVE_SYS_TIME_H #include #endif #ifdef HAVE_SYS_IOCTL_H #include #endif #ifdef HAVE_SYS_SOCKET_H #include #endif #ifdef HAVE_SYS_SOCKIO_H #include #endif #ifdef HAVE_NET_IF_H #include #endif #ifdef HAVE_NETINET_IN_H #include #endif #ifdef HAVE_NET_IF_DL_H #include #endif #ifdef HAVE_WINSOCK_H #include /* timeval */ #endif #include "uuidP.h" #ifdef HAVE_SRANDOM #define srand(x) srandom(x) #define rand() random() #endif #if defined(_WIN32) /* offer a limited gettimeofday on Win32 system */ #include static int gettimeofday(struct timeval *tv, struct timezone *tz) { FILETIME ft; const uint64_t c1 = 27111902; const uint64_t c2 = 3577643008UL; const uint64_t OFFSET = (c1 << 32) + c2; uint64_t filetime; GetSystemTimeAsFileTime(&ft); filetime = ft.dwHighDateTime; filetime = filetime << 32; filetime += ft.dwLowDateTime; filetime -= OFFSET; memset(tv,0, sizeof(*tv)); assert( sizeof(*tv) == sizeof(struct timeval)); tv->tv_sec = (time_t)(filetime / 10000000); /* seconds since epoch */ tv->tv_usec = (uint32_t)((filetime % 10000000) / 10); return 0; } /* provide unimplemented open call */ #define O_NONBLOCK 0 int open(const char *pathname, int flags) { return -1; } typedef int pid_t; pid_t getpid(void) { return 0; } typedef int uid_t; uid_t getuid(void) { return 0; } typedef int ssize_t; ssize_t read(int fd, void *buf, size_t count) { return -1; } #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; } #if defined(_WIN32) #include /* very important */ #include /* remember to link w/ iphlpapi.lib */ #if defined(uuid_t) #undef uuid_t #endif #define IP_LOCALHOST 0x0100007F static int get_node_id(unsigned char *byMAC) { DWORD i, dwSize; PMIB_IPADDRTABLE pAddr = NULL; MIB_IFROW iInfo; PFIXED_INFO pFI = NULL; /* Get all IP addresses held by this machine; if it's connected to a network, there's at least one that's not localhost */ dwSize = 0; GetIpAddrTable(NULL, &dwSize, TRUE); pAddr = (PMIB_IPADDRTABLE)malloc(sizeof(unsigned char) * dwSize); if (!GetIpAddrTable(pAddr, &dwSize, TRUE)) { for (i = 0; i < pAddr->dwNumEntries; ++i) { if (IP_LOCALHOST != pAddr->table[i].dwAddr) { /* Not localhost, so get the interface */ memset(&iInfo, 0, sizeof(MIB_IFROW)); iInfo.dwIndex = pAddr->table[i].dwIndex; GetIfEntry(&iInfo); if (MIB_IF_TYPE_ETHERNET == iInfo.dwType) { /*iInfo.bPhysAddr contains the MAC address of this interface*/ memcpy(byMAC, iInfo.bPhysAddr, iInfo.dwPhysAddrLen); free(pAddr); return 1; } } } } free(pAddr); return 0; } #else /* * 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; } #endif /*defined(_WIN32)*/ /* Expose get_node_id to API */ int uuid_get_node_id(unsigned char *node_id) { return get_node_id(node_id); } /* 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; uint64_t 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 += ((uint64_t) tv.tv_sec)*10000000; clock_reg += (((uint64_t) 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); }