rsa_x931.c revision 280304
1/* rsa_x931.c */ 2/* 3 * Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL project 4 * 2005. 5 */ 6/* ==================================================================== 7 * Copyright (c) 2005 The OpenSSL Project. All rights reserved. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in 18 * the documentation and/or other materials provided with the 19 * distribution. 20 * 21 * 3. All advertising materials mentioning features or use of this 22 * software must display the following acknowledgment: 23 * "This product includes software developed by the OpenSSL Project 24 * for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)" 25 * 26 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to 27 * endorse or promote products derived from this software without 28 * prior written permission. For written permission, please contact 29 * licensing@OpenSSL.org. 30 * 31 * 5. Products derived from this software may not be called "OpenSSL" 32 * nor may "OpenSSL" appear in their names without prior written 33 * permission of the OpenSSL Project. 34 * 35 * 6. Redistributions of any form whatsoever must retain the following 36 * acknowledgment: 37 * "This product includes software developed by the OpenSSL Project 38 * for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)" 39 * 40 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY 41 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 42 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 43 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR 44 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 45 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 46 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 47 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 48 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 49 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 50 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED 51 * OF THE POSSIBILITY OF SUCH DAMAGE. 52 * ==================================================================== 53 * 54 * This product includes cryptographic software written by Eric Young 55 * (eay@cryptsoft.com). This product includes software written by Tim 56 * Hudson (tjh@cryptsoft.com). 57 * 58 */ 59 60#include <stdio.h> 61#include "cryptlib.h" 62#include <openssl/bn.h> 63#include <openssl/rsa.h> 64#include <openssl/rand.h> 65#include <openssl/objects.h> 66 67int RSA_padding_add_X931(unsigned char *to, int tlen, 68 const unsigned char *from, int flen) 69{ 70 int j; 71 unsigned char *p; 72 73 /* 74 * Absolute minimum amount of padding is 1 header nibble, 1 padding 75 * nibble and 2 trailer bytes: but 1 hash if is already in 'from'. 76 */ 77 78 j = tlen - flen - 2; 79 80 if (j < 0) { 81 RSAerr(RSA_F_RSA_PADDING_ADD_X931, RSA_R_DATA_TOO_LARGE_FOR_KEY_SIZE); 82 return -1; 83 } 84 85 p = (unsigned char *)to; 86 87 /* If no padding start and end nibbles are in one byte */ 88 if (j == 0) 89 *p++ = 0x6A; 90 else { 91 *p++ = 0x6B; 92 if (j > 1) { 93 memset(p, 0xBB, j - 1); 94 p += j - 1; 95 } 96 *p++ = 0xBA; 97 } 98 memcpy(p, from, (unsigned int)flen); 99 p += flen; 100 *p = 0xCC; 101 return (1); 102} 103 104int RSA_padding_check_X931(unsigned char *to, int tlen, 105 const unsigned char *from, int flen, int num) 106{ 107 int i = 0, j; 108 const unsigned char *p; 109 110 p = from; 111 if ((num != flen) || ((*p != 0x6A) && (*p != 0x6B))) { 112 RSAerr(RSA_F_RSA_PADDING_CHECK_X931, RSA_R_INVALID_HEADER); 113 return -1; 114 } 115 116 if (*p++ == 0x6B) { 117 j = flen - 3; 118 for (i = 0; i < j; i++) { 119 unsigned char c = *p++; 120 if (c == 0xBA) 121 break; 122 if (c != 0xBB) { 123 RSAerr(RSA_F_RSA_PADDING_CHECK_X931, RSA_R_INVALID_PADDING); 124 return -1; 125 } 126 } 127 128 j -= i; 129 130 if (i == 0) { 131 RSAerr(RSA_F_RSA_PADDING_CHECK_X931, RSA_R_INVALID_PADDING); 132 return -1; 133 } 134 135 } else 136 j = flen - 2; 137 138 if (p[j] != 0xCC) { 139 RSAerr(RSA_F_RSA_PADDING_CHECK_X931, RSA_R_INVALID_TRAILER); 140 return -1; 141 } 142 143 memcpy(to, p, (unsigned int)j); 144 145 return (j); 146} 147 148/* Translate between X931 hash ids and NIDs */ 149 150int RSA_X931_hash_id(int nid) 151{ 152 switch (nid) { 153 case NID_sha1: 154 return 0x33; 155 156 case NID_sha256: 157 return 0x34; 158 159 case NID_sha384: 160 return 0x36; 161 162 case NID_sha512: 163 return 0x35; 164 165 } 166 return -1; 167} 168