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 { return M_ASN1_BIT_STRING_set(x, d, len); } 65 66 int i2c_ASN1_BIT_STRING(ASN1_BIT_STRING *a, unsigned char **pp) 67 { 68 int ret,j,bits,len; 69 unsigned char *p,*d; 70 71 if (a == NULL) return(0); 72 73 len=a->length; 74 75 if (len > 0) 76 { 77 if (a->flags & ASN1_STRING_FLAG_BITS_LEFT) 78 { 79 bits=(int)a->flags&0x07; 80 } 81 else 82 { 83 for ( ; len > 0; len--) 84 { 85 if (a->data[len-1]) break; 86 } 87 j=a->data[len-1]; 88 if (j & 0x01) bits=0; 89 else if (j & 0x02) bits=1; 90 else if (j & 0x04) bits=2; 91 else if (j & 0x08) bits=3; 92 else if (j & 0x10) bits=4; 93 else if (j & 0x20) bits=5; 94 else if (j & 0x40) bits=6; 95 else if (j & 0x80) bits=7; 96 else bits=0; /* should not happen */ 97 } 98 } 99 else 100 bits=0; 101 102 ret=1+len; 103 if (pp == NULL) return(ret); 104 105 p= *pp; 106 107 *(p++)=(unsigned char)bits; 108 d=a->data; 109 memcpy(p,d,len); 110 p+=len; 111 if (len > 0) p[-1]&=(0xff<<bits); 112 *pp=p; 113 return(ret); 114 } 115 116 ASN1_BIT_STRING *c2i_ASN1_BIT_STRING(ASN1_BIT_STRING **a, 117 const unsigned char **pp, long len) 118 { 119 ASN1_BIT_STRING *ret=NULL; 120 const unsigned char *p; 121 unsigned char *s; 122 int i; 123 124 if (len < 1) 125 { 126 i=ASN1_R_STRING_TOO_SHORT; 127 goto err; 128 } 129 130 if ((a == NULL) || ((*a) == NULL)) 131 { 132 if ((ret=M_ASN1_BIT_STRING_new()) == NULL) return(NULL); 133 } 134 else 135 ret=(*a); 136 137 p= *pp; 138 i= *(p++); 139 /* We do this to preserve the settings. If we modify 140 * the settings, via the _set_bit function, we will recalculate 141 * on output */ 142 ret->flags&= ~(ASN1_STRING_FLAG_BITS_LEFT|0x07); /* clear */ 143 ret->flags|=(ASN1_STRING_FLAG_BITS_LEFT|(i&0x07)); /* set */ 144 145 if (len-- > 1) /* using one because of the bits left byte */ 146 { 147 s=(unsigned char *)OPENSSL_malloc((int)len); 148 if (s == NULL) 149 { 150 i=ERR_R_MALLOC_FAILURE; 151 goto err; 152 } 153 memcpy(s,p,(int)len); 154 s[len-1]&=(0xff<<i); 155 p+=len; 156 } 157 else 158 s=NULL; 159 160 ret->length=(int)len; 161 if (ret->data != NULL) OPENSSL_free(ret->data); 162 ret->data=s; 163 ret->type=V_ASN1_BIT_STRING; 164 if (a != NULL) (*a)=ret; 165 *pp=p; 166 return(ret); 167 err: 168 ASN1err(ASN1_F_C2I_ASN1_BIT_STRING,i); 169 if ((ret != NULL) && ((a == NULL) || (*a != ret))) 170 M_ASN1_BIT_STRING_free(ret); 171 return(NULL); 172 } 173 174 /* These next 2 functions from Goetz Babin-Ebell <babinebell@trustcenter.de> 175 */ 176 int ASN1_BIT_STRING_set_bit(ASN1_BIT_STRING *a, int n, int value) 177 { 178 int w,v,iv; 179 unsigned char *c; 180 181 w=n/8; 182 v=1<<(7-(n&0x07)); 183 iv= ~v; 184 if (!value) v=0; 185 186 if (a == NULL) 187 return 0; 188 189 a->flags&= ~(ASN1_STRING_FLAG_BITS_LEFT|0x07); /* clear, set on write */ 190 191 if ((a->length < (w+1)) || (a->data == NULL)) 192 { 193 if (!value) return(1); /* Don't need to set */ 194 if (a->data == NULL) 195 c=(unsigned char *)OPENSSL_malloc(w+1); 196 else 197 c=(unsigned char *)OPENSSL_realloc_clean(a->data, 198 a->length, 199 w+1); 200 if (c == NULL) 201 { 202 ASN1err(ASN1_F_ASN1_BIT_STRING_SET_BIT,ERR_R_MALLOC_FAILURE); 203 return 0; 204 } 205 if (w+1-a->length > 0) memset(c+a->length, 0, w+1-a->length); 206 a->data=c; 207 a->length=w+1; 208 } 209 a->data[w]=((a->data[w])&iv)|v; 210 while ((a->length > 0) && (a->data[a->length-1] == 0)) 211 a->length--; 212 return(1); 213 } 214 215 int ASN1_BIT_STRING_get_bit(ASN1_BIT_STRING *a, int n) 216 { 217 int w,v; 218 219 w=n/8; 220 v=1<<(7-(n&0x07)); 221 if ((a == NULL) || (a->length < (w+1)) || (a->data == NULL)) 222 return(0); 223 return((a->data[w]&v) != 0); 224 } 225 226 /* 227 * Checks if the given bit string contains only bits specified by 228 * the flags vector. Returns 0 if there is at least one bit set in 'a' 229 * which is not specified in 'flags', 1 otherwise. 230 * 'len' is the length of 'flags'. 231 */ 232 int ASN1_BIT_STRING_check(ASN1_BIT_STRING *a, 233 unsigned char *flags, int flags_len) 234 { 235 int i, ok; 236 /* Check if there is one bit set at all. */ 237 if (!a || !a->data) return 1; 238 239 /* Check each byte of the internal representation of the bit string. */ 240 ok = 1; 241 for (i = 0; i < a->length && ok; ++i) 242 { 243 unsigned char mask = i < flags_len ? ~flags[i] : 0xff; 244 /* We are done if there is an unneeded bit set. */ 245 ok = (a->data[i] & mask) == 0; 246 } 247 return ok; 248 } 249