1 /* 2 * Unified UUID/GUID definition 3 * 4 * Copyright (C) 2009, Intel Corp. 5 * Huang Ying <ying.huang@intel.com> 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 * You should have received a copy of the GNU General Public License 17 * along with this program; if not, write to the Free Software 18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 19 */ 20 21 #include <linux/kernel.h> 22 #include <linux/export.h> 23 #include <linux/uuid.h> 24 #include <linux/random.h> 25 26 static void __uuid_gen_common(__u8 b[16]) 27 { 28 int i; 29 u32 r; 30 31 for (i = 0; i < 4; i++) { 32 r = random32(); 33 memcpy(b + i * 4, &r, 4); 34 } 35 /* reversion 0b10 */ 36 b[8] = (b[8] & 0x3F) | 0x80; 37 } 38 39 void uuid_le_gen(uuid_le *lu) 40 { 41 __uuid_gen_common(lu->b); 42 /* version 4 : random generation */ 43 lu->b[7] = (lu->b[7] & 0x0F) | 0x40; 44 } 45 EXPORT_SYMBOL_GPL(uuid_le_gen); 46 47 void uuid_be_gen(uuid_be *bu) 48 { 49 __uuid_gen_common(bu->b); 50 /* version 4 : random generation */ 51 bu->b[6] = (bu->b[6] & 0x0F) | 0x40; 52 } 53 EXPORT_SYMBOL_GPL(uuid_be_gen); 54