1 /* 2 * random.h -- A strong random number generator 3 * 4 * $Id$ 5 * 6 * Version 0.92, last modified 21-Sep-95 7 * 8 * Copyright Theodore Ts'o, 1994, 1995. All rights reserved. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, and the entire permission notice in its entirety, 15 * including the disclaimer of warranties. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 3. The name of the author may not be used to endorse or promote 20 * products derived from this software without specific prior 21 * written permission. 22 * 23 * ALTERNATIVELY, this product may be distributed under the terms of 24 * the GNU Public License, in which case the provisions of the GPL are 25 * required INSTEAD OF the above restrictions. (This clause is 26 * necessary due to a potential bad interaction between the GPL and 27 * the restrictions contained in a BSD-style copyright.) 28 * 29 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED 30 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 31 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 32 * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, 33 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES 34 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR 35 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 36 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 37 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 38 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED 39 * OF THE POSSIBILITY OF SUCH DAMAGE. 40 * 41 */ 42 43 /* 44 * Many kernel routines will have a use for good random numbers, 45 * for example, for truely random TCP sequence numbers, which prevent 46 * certain forms of TCP spoofing attacks. 47 * 48 */ 49 50 #ifndef _MACHINE_RANDOM_H_ 51 #define _MACHINE_RANDOM_H_ 1 52 53 #include <sys/ioctl.h> 54 55 #define MEM_SETIRQ _IOW('r', 1, int) /* set interrupt */ 56 #define MEM_CLEARIRQ _IOW('r', 2, int) /* clear interrupt */ 57 #define MEM_RETURNIRQ _IOR('r', 3, int) /* return interrupt */ 58 59 /* Interrupts to be used in the randomising process */ 60 61 extern u_int16_t interrupt_allowed; 62 63 /* Exported functions */ 64 65 void rand_initialize(void); 66 void add_keyboard_randomness(u_char scancode); 67 68 void get_random_bytes(void *buf, u_int nbytes); 69 u_int read_random(char *buf, u_int size); 70 u_int read_random_unlimited(char *buf, u_int size); 71 72 #endif 73