1 /* crypto/asn1/a_bitstr.c */ 2 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com) 3 * All rights reserved. 4 * 5 * This package is an SSL implementation written 6 * by Eric Young (eay@cryptsoft.com). 7 * The implementation was written so as to conform with Netscapes SSL. 8 * 9 * This library is free for commercial and non-commercial use as long as 10 * the following conditions are aheared to. The following conditions 11 * apply to all code found in this distribution, be it the RC4, RSA, 12 * lhash, DES, etc., code; not just the SSL code. The SSL documentation 13 * included with this distribution is covered by the same copyright terms 14 * except that the holder is Tim Hudson (tjh@cryptsoft.com). 15 * 16 * Copyright remains Eric Young's, and as such any Copyright notices in 17 * the code are not to be removed. 18 * If this package is used in a product, Eric Young should be given attribution 19 * as the author of the parts of the library used. 20 * This can be in the form of a textual message at program startup or 21 * in documentation (online or textual) provided with the package. 22 * 23 * Redistribution and use in source and binary forms, with or without 24 * modification, are permitted provided that the following conditions 25 * are met: 26 * 1. Redistributions of source code must retain the copyright 27 * notice, this list of conditions and the following disclaimer. 28 * 2. Redistributions in binary form must reproduce the above copyright 29 * notice, this list of conditions and the following disclaimer in the 30 * documentation and/or other materials provided with the distribution. 31 * 3. All advertising materials mentioning features or use of this software 32 * must display the following acknowledgement: 33 * "This product includes cryptographic software written by 34 * Eric Young (eay@cryptsoft.com)" 35 * The word 'cryptographic' can be left out if the rouines from the library 36 * being used are not cryptographic related :-). 37 * 4. If you include any Windows specific code (or a derivative thereof) from 38 * the apps directory (application code) you must include an acknowledgement: 39 * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)" 40 * 41 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND 42 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 43 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 44 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 45 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 46 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 47 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 48 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 49 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 50 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 51 * SUCH DAMAGE. 52 * 53 * The licence and distribution terms for any publically available version or 54 * derivative of this code cannot be changed. i.e. this code cannot simply be 55 * copied and put under another distribution licence 56 * [including the GNU Public Licence.] 57 */ 58 59 #include <stdio.h> 60 #include "cryptlib.h" 61 #include <openssl/asn1.h> 62 63 int ASN1_BIT_STRING_set(ASN1_BIT_STRING *x, unsigned char *d, int len) 64 { 65 return M_ASN1_BIT_STRING_set(x, d, len); 66 } 67 68 int i2c_ASN1_BIT_STRING(ASN1_BIT_STRING *a, unsigned char **pp) 69 { 70 int ret, j, bits, len; 71 unsigned char *p, *d; 72 73 if (a == NULL) 74 return (0); 75 76 len = a->length; 77 78 if (len > 0) { 79 if (a->flags & ASN1_STRING_FLAG_BITS_LEFT) { 80 bits = (int)a->flags & 0x07; 81 } else { 82 for (; len > 0; len--) { 83 if (a->data[len - 1]) 84 break; 85 } 86 j = a->data[len - 1]; 87 if (j & 0x01) 88 bits = 0; 89 else if (j & 0x02) 90 bits = 1; 91 else if (j & 0x04) 92 bits = 2; 93 else if (j & 0x08) 94 bits = 3; 95 else if (j & 0x10) 96 bits = 4; 97 else if (j & 0x20) 98 bits = 5; 99 else if (j & 0x40) 100 bits = 6; 101 else if (j & 0x80) 102 bits = 7; 103 else 104 bits = 0; /* should not happen */ 105 } 106 } else 107 bits = 0; 108 109 ret = 1 + len; 110 if (pp == NULL) 111 return (ret); 112 113 p = *pp; 114 115 *(p++) = (unsigned char)bits; 116 d = a->data; 117 if (len > 0) { 118 memcpy(p, d, len); 119 p += len; 120 p[-1] &= (0xff << bits); 121 } 122 *pp = p; 123 return (ret); 124 } 125 126 ASN1_BIT_STRING *c2i_ASN1_BIT_STRING(ASN1_BIT_STRING **a, 127 const unsigned char **pp, long len) 128 { 129 ASN1_BIT_STRING *ret = NULL; 130 const unsigned char *p; 131 unsigned char *s; 132 int i; 133 134 if (len < 1) { 135 i = ASN1_R_STRING_TOO_SHORT; 136 goto err; 137 } 138 139 if ((a == NULL) || ((*a) == NULL)) { 140 if ((ret = M_ASN1_BIT_STRING_new()) == NULL) 141 return (NULL); 142 } else 143 ret = (*a); 144 145 p = *pp; 146 i = *(p++); 147 if (i > 7) { 148 i = ASN1_R_INVALID_BIT_STRING_BITS_LEFT; 149 goto err; 150 } 151 /* 152 * We do this to preserve the settings. If we modify the settings, via 153 * the _set_bit function, we will recalculate on output 154 */ 155 ret->flags &= ~(ASN1_STRING_FLAG_BITS_LEFT | 0x07); /* clear */ 156 ret->flags |= (ASN1_STRING_FLAG_BITS_LEFT | i); /* set */ 157 158 if (len-- > 1) { /* using one because of the bits left byte */ 159 s = (unsigned char *)OPENSSL_malloc((int)len); 160 if (s == NULL) { 161 i = ERR_R_MALLOC_FAILURE; 162 goto err; 163 } 164 memcpy(s, p, (int)len); 165 s[len - 1] &= (0xff << i); 166 p += len; 167 } else 168 s = NULL; 169 170 ret->length = (int)len; 171 if (ret->data != NULL) 172 OPENSSL_free(ret->data); 173 ret->data = s; 174 ret->type = V_ASN1_BIT_STRING; 175 if (a != NULL) 176 (*a) = ret; 177 *pp = p; 178 return (ret); 179 err: 180 ASN1err(ASN1_F_C2I_ASN1_BIT_STRING, i); 181 if ((ret != NULL) && ((a == NULL) || (*a != ret))) 182 M_ASN1_BIT_STRING_free(ret); 183 return (NULL); 184 } 185 186 /* 187 * These next 2 functions from Goetz Babin-Ebell <babinebell@trustcenter.de> 188 */ 189 int ASN1_BIT_STRING_set_bit(ASN1_BIT_STRING *a, int n, int value) 190 { 191 int w, v, iv; 192 unsigned char *c; 193 194 w = n / 8; 195 v = 1 << (7 - (n & 0x07)); 196 iv = ~v; 197 if (!value) 198 v = 0; 199 200 if (a == NULL) 201 return 0; 202 203 a->flags &= ~(ASN1_STRING_FLAG_BITS_LEFT | 0x07); /* clear, set on write */ 204 205 if ((a->length < (w + 1)) || (a->data == NULL)) { 206 if (!value) 207 return (1); /* Don't need to set */ 208 if (a->data == NULL) 209 c = (unsigned char *)OPENSSL_malloc(w + 1); 210 else 211 c = (unsigned char *)OPENSSL_realloc_clean(a->data, 212 a->length, w + 1); 213 if (c == NULL) { 214 ASN1err(ASN1_F_ASN1_BIT_STRING_SET_BIT, ERR_R_MALLOC_FAILURE); 215 return 0; 216 } 217 if (w + 1 - a->length > 0) 218 memset(c + a->length, 0, w + 1 - a->length); 219 a->data = c; 220 a->length = w + 1; 221 } 222 a->data[w] = ((a->data[w]) & iv) | v; 223 while ((a->length > 0) && (a->data[a->length - 1] == 0)) 224 a->length--; 225 return (1); 226 } 227 228 int ASN1_BIT_STRING_get_bit(ASN1_BIT_STRING *a, int n) 229 { 230 int w, v; 231 232 w = n / 8; 233 v = 1 << (7 - (n & 0x07)); 234 if ((a == NULL) || (a->length < (w + 1)) || (a->data == NULL)) 235 return (0); 236 return ((a->data[w] & v) != 0); 237 } 238 239 /* 240 * Checks if the given bit string contains only bits specified by 241 * the flags vector. Returns 0 if there is at least one bit set in 'a' 242 * which is not specified in 'flags', 1 otherwise. 243 * 'len' is the length of 'flags'. 244 */ 245 int ASN1_BIT_STRING_check(ASN1_BIT_STRING *a, 246 unsigned char *flags, int flags_len) 247 { 248 int i, ok; 249 /* Check if there is one bit set at all. */ 250 if (!a || !a->data) 251 return 1; 252 253 /* 254 * Check each byte of the internal representation of the bit string. 255 */ 256 ok = 1; 257 for (i = 0; i < a->length && ok; ++i) { 258 unsigned char mask = i < flags_len ? ~flags[i] : 0xff; 259 /* We are done if there is an unneeded bit set. */ 260 ok = (a->data[i] & mask) == 0; 261 } 262 return ok; 263 } 264