/* * viruuid.c: helper APIs for dealing with UUIDs * * Copyright (C) 2007-2014 Red Hat, Inc. * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this library. If not, see * . */ #include #include "viruuid.h" #include #include #include #include #include #include "internal.h" #include "virerror.h" #include "virlog.h" #include "viralloc.h" #include "virfile.h" #include "virrandom.h" VIR_LOG_INIT("util.uuid"); static unsigned char host_uuid[VIR_UUID_BUFLEN]; /** * virUUIDGenerate: * @uuid: array of VIR_UUID_BUFLEN bytes to store the new UUID * * Generates a randomized unique identifier. * * Returns 0 in case of success and -1 in case of failure */ int virUUIDGenerate(unsigned char *uuid) { if (uuid == NULL) return -1; if (virRandomBytes(uuid, VIR_UUID_BUFLEN) < 0) return -1; /* * Make UUID RFC 4122 compliant. Following form will be used: * * xxxxxxxx-xxxx-Axxx-Bxxx-xxxxxxxxxxxx * * where * A is version defined in 4.1.3 of RFC * Msb0 Msb1 Msb2 Msb3 Version Description * 0 1 0 0 4 The randomly or pseudo- * randomly generated version * specified in this document. * * B is variant defined in 4.1.1 of RFC * Msb0 Msb1 Msb2 Description * 1 0 x The variant specified in this document. */ uuid[6] = (uuid[6] & 0x0F) | (4 << 4); uuid[8] = (uuid[8] & 0x3F) | (2 << 6); return 0; } /** * virUUIDParse: * @uuidstr: zero terminated string representation of the UUID * @uuid: array of VIR_UUID_BUFLEN bytes to store the raw UUID * * Parses the external string representation, allowing spaces and '-' * character in the sequence, and storing the result as a raw UUID * * Returns 0 in case of success and -1 in case of error. */ int virUUIDParse(const char *uuidstr, unsigned char *uuid) { const char *cur; size_t i; /* * do a liberal scan allowing '-' and ' ' anywhere between character * pairs, and surrounding whitespace, as long as there are exactly * 32 hexadecimal digits the end. */ cur = uuidstr; while (g_ascii_isspace(*cur)) cur++; for (i = 0; i < VIR_UUID_BUFLEN;) { int val; uuid[i] = 0; if (*cur == 0) return -1; if ((*cur == '-') || (*cur == ' ')) { cur++; continue; } if ((val = g_ascii_xdigit_value(*cur)) < 0) return -1; uuid[i] = 16 * val; cur++; if (*cur == 0) return -1; if ((val = g_ascii_xdigit_value(*cur)) < 0) return -1; uuid[i] += val; i++; cur++; } while (*cur) { if (!g_ascii_isspace(*cur)) return -1; cur++; } return 0; } /** * virUUIDFormat: * @uuid: array of VIR_UUID_BUFLEN bytes to store the raw UUID * @uuidstr: array of VIR_UUID_STRING_BUFLEN bytes to store the * string representation of the UUID in. The resulting string * will be NULL terminated. * * Converts the raw UUID into printable format, with embedded '-' * * Returns a pointer to the resulting character string. */ const char * virUUIDFormat(const unsigned char *uuid, char *uuidstr) { g_snprintf(uuidstr, VIR_UUID_STRING_BUFLEN, "%02x%02x%02x%02x-%02x%02x-%02x%02x-%02x%02x-%02x%02x%02x%02x%02x%02x", uuid[0], uuid[1], uuid[2], uuid[3], uuid[4], uuid[5], uuid[6], uuid[7], uuid[8], uuid[9], uuid[10], uuid[11], uuid[12], uuid[13], uuid[14], uuid[15]); uuidstr[VIR_UUID_STRING_BUFLEN-1] = '\0'; return uuidstr; } /** * virUUIDIsValid * * @uuid: The UUID to test * * Do some basic tests to check whether the given UUID is * valid as a host UUID. * Basic tests: * - Not all of the digits may be equal */ bool virUUIDIsValid(const unsigned char *uuid) { size_t i; if (!uuid) return false; for (i = 1; i < VIR_UUID_BUFLEN; i++) if (uuid[i] != uuid[0]) return true; return false; } static int getDMISystemUUID(char *uuid, int len) { size_t i = 0; const char *paths[] = { "/sys/devices/virtual/dmi/id/product_uuid", "/sys/class/dmi/id/product_uuid", NULL }; while (paths[i]) { if (virFileReadBufQuiet(paths[i], uuid, len) == len - 1) return 0; i++; } return -1; } /** * setHostUUID * * @host_uuid: UUID that the host is supposed to have * * Set the UUID of the host if it hasn't been set, yet * Returns 0 in case of success, an error code in case of error. */ int virSetHostUUIDStr(const char *uuid) { int rc; char dmiuuid[VIR_UUID_STRING_BUFLEN]; if (virUUIDIsValid(host_uuid)) return EEXIST; if (!uuid) { memset(dmiuuid, 0, sizeof(dmiuuid)); if (!getDMISystemUUID(dmiuuid, sizeof(dmiuuid))) { if (!virUUIDParse(dmiuuid, host_uuid)) return 0; } if (!virUUIDIsValid(host_uuid)) return virUUIDGenerate(host_uuid); } else { rc = virUUIDParse(uuid, host_uuid); if (rc) return rc; if (!virUUIDIsValid(host_uuid)) return EINVAL; } return 0; } /** * getHostUUID: * * @host_uuid: memory to store the host_uuid into * * Get the UUID of the host. Returns 0 in case of success, * an error code otherwise. * Returns 0 in case of success, an error code in case of error. */ int virGetHostUUID(unsigned char *uuid) { int ret = 0; if (!virUUIDIsValid(host_uuid)) ret = virSetHostUUIDStr(NULL); memcpy(uuid, host_uuid, sizeof(host_uuid)); return ret; }