155714Skris/* crypto/bn/bn_mpi.c */ 255714Skris/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com) 355714Skris * All rights reserved. 455714Skris * 555714Skris * This package is an SSL implementation written 655714Skris * by Eric Young (eay@cryptsoft.com). 755714Skris * The implementation was written so as to conform with Netscapes SSL. 8280297Sjkim * 955714Skris * This library is free for commercial and non-commercial use as long as 1055714Skris * the following conditions are aheared to. The following conditions 1155714Skris * apply to all code found in this distribution, be it the RC4, RSA, 1255714Skris * lhash, DES, etc., code; not just the SSL code. The SSL documentation 1355714Skris * included with this distribution is covered by the same copyright terms 1455714Skris * except that the holder is Tim Hudson (tjh@cryptsoft.com). 15280297Sjkim * 1655714Skris * Copyright remains Eric Young's, and as such any Copyright notices in 1755714Skris * the code are not to be removed. 1855714Skris * If this package is used in a product, Eric Young should be given attribution 1955714Skris * as the author of the parts of the library used. 2055714Skris * This can be in the form of a textual message at program startup or 2155714Skris * in documentation (online or textual) provided with the package. 22280297Sjkim * 2355714Skris * Redistribution and use in source and binary forms, with or without 2455714Skris * modification, are permitted provided that the following conditions 2555714Skris * are met: 2655714Skris * 1. Redistributions of source code must retain the copyright 2755714Skris * notice, this list of conditions and the following disclaimer. 2855714Skris * 2. Redistributions in binary form must reproduce the above copyright 2955714Skris * notice, this list of conditions and the following disclaimer in the 3055714Skris * documentation and/or other materials provided with the distribution. 3155714Skris * 3. All advertising materials mentioning features or use of this software 3255714Skris * must display the following acknowledgement: 3355714Skris * "This product includes cryptographic software written by 3455714Skris * Eric Young (eay@cryptsoft.com)" 3555714Skris * The word 'cryptographic' can be left out if the rouines from the library 3655714Skris * being used are not cryptographic related :-). 37280297Sjkim * 4. If you include any Windows specific code (or a derivative thereof) from 3855714Skris * the apps directory (application code) you must include an acknowledgement: 3955714Skris * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)" 40280297Sjkim * 4155714Skris * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND 4255714Skris * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 4355714Skris * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 4455714Skris * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 4555714Skris * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 4655714Skris * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 4755714Skris * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 4855714Skris * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 4955714Skris * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 5055714Skris * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 5155714Skris * SUCH DAMAGE. 52280297Sjkim * 5355714Skris * The licence and distribution terms for any publically available version or 5455714Skris * derivative of this code cannot be changed. i.e. this code cannot simply be 5555714Skris * copied and put under another distribution licence 5655714Skris * [including the GNU Public Licence.] 5755714Skris */ 5855714Skris 5955714Skris#include <stdio.h> 6055714Skris#include "cryptlib.h" 6155714Skris#include "bn_lcl.h" 6255714Skris 6355714Skrisint BN_bn2mpi(const BIGNUM *a, unsigned char *d) 64280297Sjkim{ 65280297Sjkim int bits; 66280297Sjkim int num = 0; 67280297Sjkim int ext = 0; 68280297Sjkim long l; 6955714Skris 70280297Sjkim bits = BN_num_bits(a); 71280297Sjkim num = (bits + 7) / 8; 72280297Sjkim if (bits > 0) { 73280297Sjkim ext = ((bits & 0x07) == 0); 74280297Sjkim } 75280297Sjkim if (d == NULL) 76280297Sjkim return (num + 4 + ext); 7755714Skris 78280297Sjkim l = num + ext; 79280297Sjkim d[0] = (unsigned char)(l >> 24) & 0xff; 80280297Sjkim d[1] = (unsigned char)(l >> 16) & 0xff; 81280297Sjkim d[2] = (unsigned char)(l >> 8) & 0xff; 82280297Sjkim d[3] = (unsigned char)(l) & 0xff; 83280297Sjkim if (ext) 84280297Sjkim d[4] = 0; 85280297Sjkim num = BN_bn2bin(a, &(d[4 + ext])); 86280297Sjkim if (a->neg) 87280297Sjkim d[4] |= 0x80; 88280297Sjkim return (num + 4 + ext); 89280297Sjkim} 9055714Skris 91109998SmarkmBIGNUM *BN_mpi2bn(const unsigned char *d, int n, BIGNUM *a) 92280297Sjkim{ 93280297Sjkim long len; 94280297Sjkim int neg = 0; 9555714Skris 96280297Sjkim if (n < 4) { 97280297Sjkim BNerr(BN_F_BN_MPI2BN, BN_R_INVALID_LENGTH); 98280297Sjkim return (NULL); 99280297Sjkim } 100280297Sjkim len = ((long)d[0] << 24) | ((long)d[1] << 16) | ((int)d[2] << 8) | (int) 101280297Sjkim d[3]; 102280297Sjkim if ((len + 4) != n) { 103280297Sjkim BNerr(BN_F_BN_MPI2BN, BN_R_ENCODING_ERROR); 104280297Sjkim return (NULL); 105280297Sjkim } 10655714Skris 107280297Sjkim if (a == NULL) 108280297Sjkim a = BN_new(); 109280297Sjkim if (a == NULL) 110280297Sjkim return (NULL); 11155714Skris 112280297Sjkim if (len == 0) { 113280297Sjkim a->neg = 0; 114280297Sjkim a->top = 0; 115280297Sjkim return (a); 116280297Sjkim } 117280297Sjkim d += 4; 118280297Sjkim if ((*d) & 0x80) 119280297Sjkim neg = 1; 120280297Sjkim if (BN_bin2bn(d, (int)len, a) == NULL) 121280297Sjkim return (NULL); 122280297Sjkim a->neg = neg; 123280297Sjkim if (neg) { 124280297Sjkim BN_clear_bit(a, BN_num_bits(a) - 1); 125280297Sjkim } 126280297Sjkim bn_check_top(a); 127280297Sjkim return (a); 128280297Sjkim} 129