fips_prf_openssl.c revision 214501
1214501Srpaulo/* 2214501Srpaulo * FIPS 186-2 PRF for libcrypto 3214501Srpaulo * Copyright (c) 2004-2005, Jouni Malinen <j@w1.fi> 4214501Srpaulo * 5214501Srpaulo * This program is free software; you can redistribute it and/or modify 6214501Srpaulo * it under the terms of the GNU General Public License version 2 as 7214501Srpaulo * published by the Free Software Foundation. 8214501Srpaulo * 9214501Srpaulo * Alternatively, this software may be distributed under the terms of BSD 10214501Srpaulo * license. 11214501Srpaulo * 12214501Srpaulo * See README and COPYING for more details. 13214501Srpaulo */ 14214501Srpaulo 15214501Srpaulo#include "includes.h" 16214501Srpaulo#include <openssl/sha.h> 17214501Srpaulo 18214501Srpaulo#include "common.h" 19214501Srpaulo#include "crypto.h" 20214501Srpaulo 21214501Srpaulo 22214501Srpaulostatic void sha1_transform(u8 *state, const u8 data[64]) 23214501Srpaulo{ 24214501Srpaulo SHA_CTX context; 25214501Srpaulo os_memset(&context, 0, sizeof(context)); 26214501Srpaulo os_memcpy(&context.h0, state, 5 * 4); 27214501Srpaulo SHA1_Transform(&context, data); 28214501Srpaulo os_memcpy(state, &context.h0, 5 * 4); 29214501Srpaulo} 30214501Srpaulo 31214501Srpaulo 32214501Srpauloint fips186_2_prf(const u8 *seed, size_t seed_len, u8 *x, size_t xlen) 33214501Srpaulo{ 34214501Srpaulo u8 xkey[64]; 35214501Srpaulo u32 t[5], _t[5]; 36214501Srpaulo int i, j, m, k; 37214501Srpaulo u8 *xpos = x; 38214501Srpaulo u32 carry; 39214501Srpaulo 40214501Srpaulo if (seed_len > sizeof(xkey)) 41214501Srpaulo seed_len = sizeof(xkey); 42214501Srpaulo 43214501Srpaulo /* FIPS 186-2 + change notice 1 */ 44214501Srpaulo 45214501Srpaulo os_memcpy(xkey, seed, seed_len); 46214501Srpaulo os_memset(xkey + seed_len, 0, 64 - seed_len); 47214501Srpaulo t[0] = 0x67452301; 48214501Srpaulo t[1] = 0xEFCDAB89; 49214501Srpaulo t[2] = 0x98BADCFE; 50214501Srpaulo t[3] = 0x10325476; 51214501Srpaulo t[4] = 0xC3D2E1F0; 52214501Srpaulo 53214501Srpaulo m = xlen / 40; 54214501Srpaulo for (j = 0; j < m; j++) { 55214501Srpaulo /* XSEED_j = 0 */ 56214501Srpaulo for (i = 0; i < 2; i++) { 57214501Srpaulo /* XVAL = (XKEY + XSEED_j) mod 2^b */ 58214501Srpaulo 59214501Srpaulo /* w_i = G(t, XVAL) */ 60214501Srpaulo os_memcpy(_t, t, 20); 61214501Srpaulo sha1_transform((u8 *) _t, xkey); 62214501Srpaulo _t[0] = host_to_be32(_t[0]); 63214501Srpaulo _t[1] = host_to_be32(_t[1]); 64214501Srpaulo _t[2] = host_to_be32(_t[2]); 65214501Srpaulo _t[3] = host_to_be32(_t[3]); 66214501Srpaulo _t[4] = host_to_be32(_t[4]); 67214501Srpaulo os_memcpy(xpos, _t, 20); 68214501Srpaulo 69214501Srpaulo /* XKEY = (1 + XKEY + w_i) mod 2^b */ 70214501Srpaulo carry = 1; 71214501Srpaulo for (k = 19; k >= 0; k--) { 72214501Srpaulo carry += xkey[k] + xpos[k]; 73214501Srpaulo xkey[k] = carry & 0xff; 74214501Srpaulo carry >>= 8; 75214501Srpaulo } 76214501Srpaulo 77214501Srpaulo xpos += 20; 78214501Srpaulo } 79214501Srpaulo /* x_j = w_0|w_1 */ 80214501Srpaulo } 81214501Srpaulo 82214501Srpaulo return 0; 83214501Srpaulo} 84