1 /* x_long.c */ 2 /* Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL 3 * project 2000. 4 */ 5 /* ==================================================================== 6 * Copyright (c) 2000 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 "cryptlib.h" 61 #include <openssl/asn1t.h> 62 #include <openssl/bn.h> 63 64 /* Custom primitive type for long handling. This converts between an ASN1_INTEGER 65 * and a long directly. 66 */ 67 68 69 static int long_new(ASN1_VALUE **pval, const ASN1_ITEM *it); 70 static void long_free(ASN1_VALUE **pval, const ASN1_ITEM *it); 71 72 static int long_i2c(ASN1_VALUE **pval, unsigned char *cont, int *putype, const ASN1_ITEM *it); 73 static int long_c2i(ASN1_VALUE **pval, const unsigned char *cont, int len, int utype, char *free_cont, const ASN1_ITEM *it); 74 75 static ASN1_PRIMITIVE_FUNCS long_pf = { 76 NULL, 0, 77 long_new, 78 long_free, 79 long_free, /* Clear should set to initial value */ 80 long_c2i, 81 long_i2c 82 }; 83 84 ASN1_ITEM_start(LONG) 85 ASN1_ITYPE_PRIMITIVE, V_ASN1_INTEGER, NULL, 0, &long_pf, ASN1_LONG_UNDEF, "LONG" 86 ASN1_ITEM_end(LONG) 87 88 ASN1_ITEM_start(ZLONG) 89 ASN1_ITYPE_PRIMITIVE, V_ASN1_INTEGER, NULL, 0, &long_pf, 0, "ZLONG" 90 ASN1_ITEM_end(ZLONG) 91 92 static int long_new(ASN1_VALUE **pval, const ASN1_ITEM *it) 93 { 94 *(long *)pval = it->size; 95 return 1; 96 } 97 98 static void long_free(ASN1_VALUE **pval, const ASN1_ITEM *it) 99 { 100 *(long *)pval = it->size; 101 } 102 103 static int long_i2c(ASN1_VALUE **pval, unsigned char *cont, int *putype, const ASN1_ITEM *it) 104 { 105 long ltmp; 106 unsigned long utmp; 107 int clen, pad, i; 108 /* this exists to bypass broken gcc optimization */ 109 char *cp = (char *)pval; 110 111 /* use memcpy, because we may not be long aligned */ 112 memcpy(<mp, cp, sizeof(long)); 113 114 if(ltmp == it->size) return -1; 115 /* Convert the long to positive: we subtract one if negative so 116 * we can cleanly handle the padding if only the MSB of the leading 117 * octet is set. 118 */ 119 if(ltmp < 0) utmp = -ltmp - 1; 120 else utmp = ltmp; 121 clen = BN_num_bits_word(utmp); 122 /* If MSB of leading octet set we need to pad */ 123 if(!(clen & 0x7)) pad = 1; 124 else pad = 0; 125 126 /* Convert number of bits to number of octets */ 127 clen = (clen + 7) >> 3; 128 129 if(cont) { 130 if(pad) *cont++ = (ltmp < 0) ? 0xff : 0; 131 for(i = clen - 1; i >= 0; i--) { 132 cont[i] = (unsigned char)(utmp & 0xff); 133 if(ltmp < 0) cont[i] ^= 0xff; 134 utmp >>= 8; 135 } 136 } 137 return clen + pad; 138 } 139 140 static int long_c2i(ASN1_VALUE **pval, const unsigned char *cont, int len, 141 int utype, char *free_cont, const ASN1_ITEM *it) 142 { 143 int neg, i; 144 long ltmp; 145 unsigned long utmp = 0; 146 char *cp = (char *)pval; 147 if(len > (int)sizeof(long)) { 148 ASN1err(ASN1_F_LONG_C2I, ASN1_R_INTEGER_TOO_LARGE_FOR_LONG); 149 return 0; 150 } 151 /* Is it negative? */ 152 if(len && (cont[0] & 0x80)) neg = 1; 153 else neg = 0; 154 utmp = 0; 155 for(i = 0; i < len; i++) { 156 utmp <<= 8; 157 if(neg) utmp |= cont[i] ^ 0xff; 158 else utmp |= cont[i]; 159 } 160 ltmp = (long)utmp; 161 if(neg) { 162 ltmp++; 163 ltmp = -ltmp; 164 } 165 if(ltmp == it->size) { 166 ASN1err(ASN1_F_LONG_C2I, ASN1_R_INTEGER_TOO_LARGE_FOR_LONG); 167 return 0; 168 } 169 memcpy(cp, <mp, sizeof(long)); 170 return 1; 171 } 172