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/asn1.h> 58 59 #include <string.h> 60 61 #include <openssl/err.h> 62 #include <openssl/mem.h> 63 64 #include "../internal.h" 65 66 67 int ASN1_BIT_STRING_set(ASN1_BIT_STRING *x, unsigned char *d, int len) 68 { 69 return M_ASN1_BIT_STRING_set(x, d, len); 70 } 71 72 int i2c_ASN1_BIT_STRING(ASN1_BIT_STRING *a, unsigned char **pp) 73 { 74 int ret, j, bits, len; 75 unsigned char *p, *d; 76 77 if (a == NULL) 78 return (0); 79 80 len = a->length; 81 82 if (len > 0) { 83 if (a->flags & ASN1_STRING_FLAG_BITS_LEFT) { 84 bits = (int)a->flags & 0x07; 85 } else { 86 for (; len > 0; len--) { 87 if (a->data[len - 1]) 88 break; 89 } 90 j = a->data[len - 1]; 91 if (j & 0x01) 92 bits = 0; 93 else if (j & 0x02) 94 bits = 1; 95 else if (j & 0x04) 96 bits = 2; 97 else if (j & 0x08) 98 bits = 3; 99 else if (j & 0x10) 100 bits = 4; 101 else if (j & 0x20) 102 bits = 5; 103 else if (j & 0x40) 104 bits = 6; 105 else if (j & 0x80) 106 bits = 7; 107 else 108 bits = 0; /* should not happen */ 109 } 110 } else 111 bits = 0; 112 113 ret = 1 + len; 114 if (pp == NULL) 115 return (ret); 116 117 p = *pp; 118 119 *(p++) = (unsigned char)bits; 120 d = a->data; 121 OPENSSL_memcpy(p, d, len); 122 p += len; 123 if (len > 0) 124 p[-1] &= (0xff << bits); 125 *pp = p; 126 return (ret); 127 } 128 129 ASN1_BIT_STRING *c2i_ASN1_BIT_STRING(ASN1_BIT_STRING **a, 130 const unsigned char **pp, long len) 131 { 132 ASN1_BIT_STRING *ret = NULL; 133 const unsigned char *p; 134 unsigned char *s; 135 int padding; 136 137 if (len < 1) { 138 OPENSSL_PUT_ERROR(ASN1, ASN1_R_STRING_TOO_SHORT); 139 goto err; 140 } 141 142 if ((a == NULL) || ((*a) == NULL)) { 143 if ((ret = M_ASN1_BIT_STRING_new()) == NULL) 144 return (NULL); 145 } else 146 ret = (*a); 147 148 p = *pp; 149 padding = *(p++); 150 if (padding > 7) { 151 OPENSSL_PUT_ERROR(ASN1, ASN1_R_INVALID_BIT_STRING_BITS_LEFT); 152 goto err; 153 } 154 155 /* 156 * We do this to preserve the settings. If we modify the settings, via 157 * the _set_bit function, we will recalculate on output 158 */ 159 ret->flags &= ~(ASN1_STRING_FLAG_BITS_LEFT | 0x07); /* clear */ 160 ret->flags |= (ASN1_STRING_FLAG_BITS_LEFT | padding); /* set */ 161 162 if (len-- > 1) { /* using one because of the bits left byte */ 163 s = (unsigned char *)OPENSSL_malloc((int)len); 164 if (s == NULL) { 165 OPENSSL_PUT_ERROR(ASN1, ERR_R_MALLOC_FAILURE); 166 goto err; 167 } 168 OPENSSL_memcpy(s, p, (int)len); 169 s[len - 1] &= (0xff << padding); 170 p += len; 171 } else 172 s = NULL; 173 174 ret->length = (int)len; 175 if (ret->data != NULL) 176 OPENSSL_free(ret->data); 177 ret->data = s; 178 ret->type = V_ASN1_BIT_STRING; 179 if (a != NULL) 180 (*a) = ret; 181 *pp = p; 182 return (ret); 183 err: 184 if ((ret != NULL) && ((a == NULL) || (*a != ret))) 185 M_ASN1_BIT_STRING_free(ret); 186 return (NULL); 187 } 188 189 /* 190 * These next 2 functions from Goetz Babin-Ebell <babinebell (at) trustcenter.de> 191 */ 192 int ASN1_BIT_STRING_set_bit(ASN1_BIT_STRING *a, int n, int value) 193 { 194 int w, v, iv; 195 unsigned char *c; 196 197 w = n / 8; 198 v = 1 << (7 - (n & 0x07)); 199 iv = ~v; 200 if (!value) 201 v = 0; 202 203 if (a == NULL) 204 return 0; 205 206 a->flags &= ~(ASN1_STRING_FLAG_BITS_LEFT | 0x07); /* clear, set on write */ 207 208 if ((a->length < (w + 1)) || (a->data == NULL)) { 209 if (!value) 210 return (1); /* Don't need to set */ 211 if (a->data == NULL) 212 c = (unsigned char *)OPENSSL_malloc(w + 1); 213 else 214 c = (unsigned char *)OPENSSL_realloc_clean(a->data, 215 a->length, w + 1); 216 if (c == NULL) { 217 OPENSSL_PUT_ERROR(ASN1, ERR_R_MALLOC_FAILURE); 218 return 0; 219 } 220 if (w + 1 - a->length > 0) 221 OPENSSL_memset(c + a->length, 0, w + 1 - a->length); 222 a->data = c; 223 a->length = w + 1; 224 } 225 a->data[w] = ((a->data[w]) & iv) | v; 226 while ((a->length > 0) && (a->data[a->length - 1] == 0)) 227 a->length--; 228 return (1); 229 } 230 231 int ASN1_BIT_STRING_get_bit(ASN1_BIT_STRING *a, int n) 232 { 233 int w, v; 234 235 w = n / 8; 236 v = 1 << (7 - (n & 0x07)); 237 if ((a == NULL) || (a->length < (w + 1)) || (a->data == NULL)) 238 return (0); 239 return ((a->data[w] & v) != 0); 240 } 241 242 /* 243 * Checks if the given bit string contains only bits specified by 244 * the flags vector. Returns 0 if there is at least one bit set in 'a' 245 * which is not specified in 'flags', 1 otherwise. 246 * 'len' is the length of 'flags'. 247 */ 248 int ASN1_BIT_STRING_check(ASN1_BIT_STRING *a, 249 unsigned char *flags, int flags_len) 250 { 251 int i, ok; 252 /* Check if there is one bit set at all. */ 253 if (!a || !a->data) 254 return 1; 255 256 /* 257 * Check each byte of the internal representation of the bit string. 258 */ 259 ok = 1; 260 for (i = 0; i < a->length && ok; ++i) { 261 unsigned char mask = i < flags_len ? ~flags[i] : 0xff; 262 /* We are done if there is an unneeded bit set. */ 263 ok = (a->data[i] & mask) == 0; 264 } 265 return ok; 266 } 267