1 /* 2 * UUID/GUID definition 3 * 4 * Copyright (C) 2010, 2016 Intel Corp. 5 * Huang Ying <[email protected]> 6 * 7 * This program is free software; you can redistribute it and/or 8 * modify it under the terms of the GNU General Public License version 9 * 2 as published by the Free Software Foundation; 10 * 11 * This program is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 * GNU General Public License for more details. 15 */ 16 #ifndef _LINUX_UUID_H_ 17 #define _LINUX_UUID_H_ 18 19 #include <uapi/linux/uuid.h> 20 21 /* 22 * V1 (time-based) UUID definition [RFC 4122]. 23 * - the timestamp is a 60-bit value, split 32/16/12, and goes in 100ns 24 * increments since midnight 15th October 1582 25 * - add AFS_UUID_TO_UNIX_TIME to convert unix time in 100ns units to UUID 26 * time 27 * - the clock sequence is a 14-bit counter to avoid duplicate times 28 */ 29 struct uuid_v1 { 30 __be32 time_low; /* low part of timestamp */ 31 __be16 time_mid; /* mid part of timestamp */ 32 __be16 time_hi_and_version; /* high part of timestamp and version */ 33 #define UUID_TO_UNIX_TIME 0x01b21dd213814000ULL 34 #define UUID_TIMEHI_MASK 0x0fff 35 #define UUID_VERSION_TIME 0x1000 /* time-based UUID */ 36 #define UUID_VERSION_NAME 0x3000 /* name-based UUID */ 37 #define UUID_VERSION_RANDOM 0x4000 /* (pseudo-)random generated UUID */ 38 u8 clock_seq_hi_and_reserved; /* clock seq hi and variant */ 39 #define UUID_CLOCKHI_MASK 0x3f 40 #define UUID_VARIANT_STD 0x80 41 u8 clock_seq_low; /* clock seq low */ 42 u8 node[6]; /* spatially unique node ID (MAC addr) */ 43 }; 44 45 /* 46 * The length of a UUID string ("aaaaaaaa-bbbb-cccc-dddd-eeeeeeeeeeee") 47 * not including trailing NUL. 48 */ 49 #define UUID_STRING_LEN 36 50 51 static inline int uuid_le_cmp(const uuid_le u1, const uuid_le u2) 52 { 53 return memcmp(&u1, &u2, sizeof(uuid_le)); 54 } 55 56 static inline int uuid_be_cmp(const uuid_be u1, const uuid_be u2) 57 { 58 return memcmp(&u1, &u2, sizeof(uuid_be)); 59 } 60 61 void generate_random_uuid(unsigned char uuid[16]); 62 63 extern void uuid_le_gen(uuid_le *u); 64 extern void uuid_be_gen(uuid_be *u); 65 66 bool __must_check uuid_is_valid(const char *uuid); 67 68 extern const u8 uuid_le_index[16]; 69 extern const u8 uuid_be_index[16]; 70 71 int uuid_le_to_bin(const char *uuid, uuid_le *u); 72 int uuid_be_to_bin(const char *uuid, uuid_be *u); 73 74 #endif 75