/* Serval DNA Universally Unique Identifier support Copyright (C) 2013 Serval Project Inc. This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This program 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 General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */ #ifndef __SERVAL_DNA__SERVAL_UUID_H #define __SERVAL_DNA__SERVAL_UUID_H #include <stdint.h> #include <alloca.h> #include <string.h> #include "strbuf.h" #ifndef __SERVAL_DNA__SERVAL_UUID_H_INLINE # if __GNUC__ && !__GNUC_STDC_INLINE__ # define __SERVAL_DNA__SERVAL_UUID_H_INLINE extern inline # else # define __SERVAL_DNA__SERVAL_UUID_H_INLINE inline # endif #endif /* A UUID is defined by RFC-4122 as a 128-bit identifier with the two most * significant bits of the ninth byte being 1 and 0, which indicates the * "variant" that is described by the RFC. Other variants exist, but are not * supported here, and are treated as INVALID by the functions defined below. * Any attempt to pass an invalid UUID to a function that requires a valid UUID * as input will probably result in the calling process being aborted (see * SIGABRT, abort(3)). * * In a valid UUID, the four lowest significant bits of the seventh byte define * the "version" of the UUID, which essentially indicates how it was generated. * The RFC defines five SUPPORTED versions. Any other version is UNSUPPORTED. * * The fields in the UUID 'record' structure are stored in network byte order, * so code wishing to make use of the record structure must use ntohl(3) and * ntohs(3) to read values, and htonl(3) and htons(3) to assign values. * * OS-X already defines a "uuid_t" typedef and has a "uuid_generate_random()" * function, so all symbols defined in this file are prefixed with * serval_uuid_ to avoid potential collisions on OS-X and other platforms. * * @author Andrew Bettison <andrew@servalproject.com> */ typedef struct serval_uuid { union { struct { uint32_t time_low; uint16_t time_mid; uint16_t time_hi_and_version; uint8_t clock_seq_hi_and_reserved; uint8_t clock_seq_low; unsigned char node[6]; // uint48_t } record; unsigned char binary[16]; } u; } serval_uuid_t; enum serval_uuid_version { UUID_VERSION_UNSUPPORTED = 0, UUID_VERSION_TIME_BASED = 1, UUID_VERSION_DCE_SECURITY = 2, UUID_VERSION_NAME_MD5 = 3, UUID_VERSION_RANDOM = 4, UUID_VERSION_NAME_SHA1 = 5 }; __SERVAL_DNA__SERVAL_UUID_H_INLINE int cmp_serval_uuid_t(const serval_uuid_t *a, const serval_uuid_t *b) { return memcmp(a->u.binary, b->u.binary, sizeof a->u.binary); } __SERVAL_DNA__SERVAL_UUID_H_INLINE int serval_uuid_is_valid(const serval_uuid_t *any_uuid) { return (any_uuid->u.record.clock_seq_hi_and_reserved & 0xc0) == 0x80; } enum serval_uuid_version serval_uuid_get_version(const serval_uuid_t *valid_uuid); void serval_uuid_set_version(serval_uuid_t *valid_uuid, enum serval_uuid_version); /* Returns -1 if error (eg, cannot open /dev/urandom), 0 if successful. */ int serval_uuid_generate_random(serval_uuid_t *dest_uuid); /* Formats the given valid UUID in its canonical string representation: * XXXXXXXX-VXXX-MXXX-XXXXXXXXXXXX * where X is any hex digit * V is 1, 2, 3, 4 or 5 (supported versions) or any other hex digit * (unsupported versions) * M is 8, 9, A or B (high two bits are variant 01) * * The 'dst' argument must point to a buffer of 37 bytes. The first 36 bytes * are filled with the representation shown above, and the 37th byte dst[36] is * set to NUL '\0'. * * Returns the 'dst' argument. * * @author Andrew Bettison <andrew@servalproject.com> */ char *serval_uuid_to_str(const serval_uuid_t *valid_uuid, char *dst); #define SERVAL_UUID_STRLEN 36 #define alloca_uuid_str(uuid) serval_uuid_to_str(&(uuid), alloca(SERVAL_UUID_STRLEN + 1)) /* Append a UUID to the given strbuf, formatted as per the serval_uuid_to_str() function. */ strbuf strbuf_uuid(strbuf, const serval_uuid_t *valid_uuid); /* Parse a canonical UUID string (as generated by serval_uuid_to_str()) into a valid * UUID, which may or not be supported. * * Returns 1 if a valid UUID is parsed, storing the value in *result (unless result is NULL) and * storing a pointer to the immediately succeeding character in *afterp. If afterp is NULL then * returns 0 unless the immediately succeeding character is a NUL '\0'. If no UUID is parsed or * if the UUID is not valid, then returns 0, leaving *result unchanged and * setting setting *afterp to point to the character where parsing failed. * * @author Andrew Bettison <andrew@servalproject.com> */ int str_to_serval_uuid(const char *str, serval_uuid_t *result, const char **afterp); #endif //__SERVAL_DNA__SERVAL_UUID_H