1 /* $OpenBSD: rsa_x931.c,v 1.8 2014/07/11 08:44:49 jsing Exp $ */ 2 /* Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL 3 * project 2005. 4 */ 5 /* ==================================================================== 6 * Copyright (c) 2005 The OpenSSL Project. All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in 17 * the documentation and/or other materials provided with the 18 * distribution. 19 * 20 * 3. All advertising materials mentioning features or use of this 21 * software must display the following acknowledgment: 22 * "This product includes software developed by the OpenSSL Project 23 * for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)" 24 * 25 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to 26 * endorse or promote products derived from this software without 27 * prior written permission. For written permission, please contact 28 * licensing@OpenSSL.org. 29 * 30 * 5. Products derived from this software may not be called "OpenSSL" 31 * nor may "OpenSSL" appear in their names without prior written 32 * permission of the OpenSSL Project. 33 * 34 * 6. Redistributions of any form whatsoever must retain the following 35 * acknowledgment: 36 * "This product includes software developed by the OpenSSL Project 37 * for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)" 38 * 39 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY 40 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 41 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 42 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR 43 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 44 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 45 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 46 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 47 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 48 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 49 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED 50 * OF THE POSSIBILITY OF SUCH DAMAGE. 51 * ==================================================================== 52 * 53 * This product includes cryptographic software written by Eric Young 54 * (eay@cryptsoft.com). This product includes software written by Tim 55 * Hudson (tjh@cryptsoft.com). 56 * 57 */ 58 59 #include <stdio.h> 60 #include <string.h> 61 62 #include <openssl/bn.h> 63 #include <openssl/err.h> 64 #include <openssl/objects.h> 65 #include <openssl/rand.h> 66 #include <openssl/rsa.h> 67 68 int 69 RSA_padding_add_X931(unsigned char *to, int tlen, const unsigned char *from, 70 int flen) 71 { 72 int j; 73 unsigned char *p; 74 75 /* 76 * Absolute minimum amount of padding is 1 header nibble, 1 padding 77 * nibble and 2 trailer bytes: but 1 hash if is already in 'from'. 78 */ 79 j = tlen - flen - 2; 80 81 if (j < 0) { 82 RSAerr(RSA_F_RSA_PADDING_ADD_X931, 83 RSA_R_DATA_TOO_LARGE_FOR_KEY_SIZE); 84 return -1; 85 } 86 87 p = (unsigned char *)to; 88 89 /* If no padding start and end nibbles are in one byte */ 90 if (j == 0) 91 *p++ = 0x6A; 92 else { 93 *p++ = 0x6B; 94 if (j > 1) { 95 memset(p, 0xBB, j - 1); 96 p += j - 1; 97 } 98 *p++ = 0xBA; 99 } 100 memcpy(p, from, flen); 101 p += flen; 102 *p = 0xCC; 103 return 1; 104 } 105 106 int 107 RSA_padding_check_X931(unsigned char *to, int tlen, const unsigned char *from, 108 int flen, int num) 109 { 110 int i = 0, j; 111 const unsigned char *p = from; 112 113 if (num != flen || (*p != 0x6A && *p != 0x6B)) { 114 RSAerr(RSA_F_RSA_PADDING_CHECK_X931, RSA_R_INVALID_HEADER); 115 return -1; 116 } 117 118 if (*p++ == 0x6B) { 119 j = flen - 3; 120 for (i = 0; i < j; i++) { 121 unsigned char c = *p++; 122 if (c == 0xBA) 123 break; 124 if (c != 0xBB) { 125 RSAerr(RSA_F_RSA_PADDING_CHECK_X931, 126 RSA_R_INVALID_PADDING); 127 return -1; 128 } 129 } 130 131 if (i == 0) { 132 RSAerr(RSA_F_RSA_PADDING_CHECK_X931, 133 RSA_R_INVALID_PADDING); 134 return -1; 135 } 136 137 j -= i; 138 } else 139 j = flen - 2; 140 141 if (j < 0 || p[j] != 0xCC) { 142 RSAerr(RSA_F_RSA_PADDING_CHECK_X931, RSA_R_INVALID_TRAILER); 143 return -1; 144 } 145 146 memcpy(to, p, j); 147 148 return j; 149 } 150 151 /* Translate between X931 hash ids and NIDs */ 152 153 int 154 RSA_X931_hash_id(int nid) 155 { 156 switch (nid) { 157 case NID_sha1: 158 return 0x33; 159 case NID_sha256: 160 return 0x34; 161 case NID_sha384: 162 return 0x36; 163 case NID_sha512: 164 return 0x35; 165 } 166 167 return -1; 168 } 169