1 /* Copyright (C) 1995-1998 Eric Young (eay (at) cryptsoft.com) 2 * All rights reserved. 3 * 4 * This package is an SSL implementation written 5 * by Eric Young (eay (at) cryptsoft.com). 6 * The implementation was written so as to conform with Netscapes SSL. 7 * 8 * This library is free for commercial and non-commercial use as long as 9 * the following conditions are aheared to. The following conditions 10 * apply to all code found in this distribution, be it the RC4, RSA, 11 * lhash, DES, etc., code; not just the SSL code. The SSL documentation 12 * included with this distribution is covered by the same copyright terms 13 * except that the holder is Tim Hudson (tjh (at) cryptsoft.com). 14 * 15 * Copyright remains Eric Young's, and as such any Copyright notices in 16 * the code are not to be removed. 17 * If this package is used in a product, Eric Young should be given attribution 18 * as the author of the parts of the library used. 19 * This can be in the form of a textual message at program startup or 20 * in documentation (online or textual) provided with the package. 21 * 22 * Redistribution and use in source and binary forms, with or without 23 * modification, are permitted provided that the following conditions 24 * are met: 25 * 1. Redistributions of source code must retain the copyright 26 * notice, this list of conditions and the following disclaimer. 27 * 2. Redistributions in binary form must reproduce the above copyright 28 * notice, this list of conditions and the following disclaimer in the 29 * documentation and/or other materials provided with the distribution. 30 * 3. All advertising materials mentioning features or use of this software 31 * must display the following acknowledgement: 32 * "This product includes cryptographic software written by 33 * Eric Young (eay (at) cryptsoft.com)" 34 * The word 'cryptographic' can be left out if the rouines from the library 35 * being used are not cryptographic related :-). 36 * 4. If you include any Windows specific code (or a derivative thereof) from 37 * the apps directory (application code) you must include an acknowledgement: 38 * "This product includes software written by Tim Hudson (tjh (at) cryptsoft.com)" 39 * 40 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND 41 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 42 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 43 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 44 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 45 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 46 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 47 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 48 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 49 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 50 * SUCH DAMAGE. 51 * 52 * The licence and distribution terms for any publically available version or 53 * derivative of this code cannot be changed. i.e. this code cannot simply be 54 * copied and put under another distribution licence 55 * [including the GNU Public Licence.] */ 56 57 #include <openssl/bn.h> 58 59 #include "internal.h" 60 61 62 int BN_ucmp(const BIGNUM *a, const BIGNUM *b) { 63 int i; 64 BN_ULONG t1, t2, *ap, *bp; 65 66 i = a->top - b->top; 67 if (i != 0) { 68 return i; 69 } 70 71 ap = a->d; 72 bp = b->d; 73 for (i = a->top - 1; i >= 0; i--) { 74 t1 = ap[i]; 75 t2 = bp[i]; 76 if (t1 != t2) { 77 return (t1 > t2) ? 1 : -1; 78 } 79 } 80 81 return 0; 82 } 83 84 int BN_cmp(const BIGNUM *a, const BIGNUM *b) { 85 int i; 86 int gt, lt; 87 BN_ULONG t1, t2; 88 89 if ((a == NULL) || (b == NULL)) { 90 if (a != NULL) { 91 return -1; 92 } else if (b != NULL) { 93 return 1; 94 } else { 95 return 0; 96 } 97 } 98 99 if (a->neg != b->neg) { 100 if (a->neg) { 101 return -1; 102 } 103 return 1; 104 } 105 if (a->neg == 0) { 106 gt = 1; 107 lt = -1; 108 } else { 109 gt = -1; 110 lt = 1; 111 } 112 113 if (a->top > b->top) { 114 return gt; 115 } 116 if (a->top < b->top) { 117 return lt; 118 } 119 120 for (i = a->top - 1; i >= 0; i--) { 121 t1 = a->d[i]; 122 t2 = b->d[i]; 123 if (t1 > t2) { 124 return gt; 125 } if (t1 < t2) { 126 return lt; 127 } 128 } 129 130 return 0; 131 } 132 133 int bn_cmp_words(const BN_ULONG *a, const BN_ULONG *b, int n) { 134 int i; 135 BN_ULONG aa, bb; 136 137 aa = a[n - 1]; 138 bb = b[n - 1]; 139 if (aa != bb) { 140 return (aa > bb) ? 1 : -1; 141 } 142 143 for (i = n - 2; i >= 0; i--) { 144 aa = a[i]; 145 bb = b[i]; 146 if (aa != bb) { 147 return (aa > bb) ? 1 : -1; 148 } 149 } 150 return 0; 151 } 152 153 int bn_cmp_part_words(const BN_ULONG *a, const BN_ULONG *b, int cl, int dl) { 154 int n, i; 155 n = cl - 1; 156 157 if (dl < 0) { 158 for (i = dl; i < 0; i++) { 159 if (b[n - i] != 0) { 160 return -1; /* a < b */ 161 } 162 } 163 } 164 if (dl > 0) { 165 for (i = dl; i > 0; i--) { 166 if (a[n + i] != 0) { 167 return 1; /* a > b */ 168 } 169 } 170 } 171 172 return bn_cmp_words(a, b, cl); 173 } 174 175 int BN_abs_is_word(const BIGNUM *bn, BN_ULONG w) { 176 switch (bn->top) { 177 case 1: 178 return bn->d[0] == w; 179 case 0: 180 return w == 0; 181 default: 182 return 0; 183 } 184 } 185 186 int BN_is_zero(const BIGNUM *bn) { 187 return bn->top == 0; 188 } 189 190 int BN_is_one(const BIGNUM *bn) { 191 return bn->neg == 0 && BN_abs_is_word(bn, 1); 192 } 193 194 int BN_is_word(const BIGNUM *bn, BN_ULONG w) { 195 return BN_abs_is_word(bn, w) && (w == 0 || bn->neg == 0); 196 } 197 198 int BN_is_odd(const BIGNUM *bn) { 199 return bn->top > 0 && (bn->d[0] & 1) == 1; 200 } 201