crypto/asn1/a_bitstr.c

   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     memcpy(p, d, len);
 118     p += len;
 119     if (len > 0)
 120         p[-1] &= (0xff << bits);
 121     *pp = p;
 122     return (ret);
 123 }
 124
 125 ASN1_BIT_STRING *c2i_ASN1_BIT_STRING(ASN1_BIT_STRING **a,
 126                                      const unsigned char **pp, long len)
 127 {
 128     ASN1_BIT_STRING *ret = NULL;
 129     const unsigned char *p;
 130     unsigned char *s;
 131     int i;
 132
 133     if (len < 1) {
 134         i = ASN1_R_STRING_TOO_SHORT;
 135         goto err;
 136     }
 137
 138     if ((a == NULL) || ((*a) == NULL)) {
 139         if ((ret = M_ASN1_BIT_STRING_new()) == NULL)
 140             return (NULL);
 141     } else
 142         ret = (*a);
 143
 144     p = *pp;
 145     i = *(p++);
 146     if (i > 7) {
 147         i = ASN1_R_INVALID_BIT_STRING_BITS_LEFT;
 148         goto err;
 149     }
 150     /*
 151      * We do this to preserve the settings.  If we modify the settings, via
 152      * the _set_bit function, we will recalculate on output
 153      */
 154     ret->flags &= ~(ASN1_STRING_FLAG_BITS_LEFT | 0x07); /* clear */
 155     ret->flags |= (ASN1_STRING_FLAG_BITS_LEFT | i); /* set */
 156
 157     if (len-- > 1) {            /* using one because of the bits left byte */
 158         s = (unsigned char *)OPENSSL_malloc((int)len);
 159         if (s == NULL) {
 160             i = ERR_R_MALLOC_FAILURE;
 161             goto err;
 162         }
 163         memcpy(s, p, (int)len);
 164         s[len - 1] &= (0xff << i);
 165         p += len;
 166     } else
 167         s = NULL;
 168
 169     ret->length = (int)len;
 170     if (ret->data != NULL)
 171         OPENSSL_free(ret->data);
 172     ret->data = s;
 173     ret->type = V_ASN1_BIT_STRING;
 174     if (a != NULL)
 175         (*a) = ret;
 176     *pp = p;
 177     return (ret);
 178  err:
 179     ASN1err(ASN1_F_C2I_ASN1_BIT_STRING, i);
 180     if ((ret != NULL) && ((a == NULL) || (*a != ret)))
 181         M_ASN1_BIT_STRING_free(ret);
 182     return (NULL);
 183 }
 184
 185 /*
 186  * These next 2 functions from Goetz Babin-Ebell <babinebell@trustcenter.de>
 187  */
 188 int ASN1_BIT_STRING_set_bit(ASN1_BIT_STRING *a, int n, int value)
 189 {
 190     int w, v, iv;
 191     unsigned char *c;
 192
 193     w = n / 8;
 194     v = 1 << (7 - (n & 0x07));
 195     iv = ~v;
 196     if (!value)
 197         v = 0;
 198
 199     if (a == NULL)
 200         return 0;
 201
 202     a->flags &= ~(ASN1_STRING_FLAG_BITS_LEFT | 0x07); /* clear, set on write */
 203
 204     if ((a->length < (w + 1)) || (a->data == NULL)) {
 205         if (!value)
 206             return (1);         /* Don't need to set */
 207         if (a->data == NULL)
 208             c = (unsigned char *)OPENSSL_malloc(w + 1);
 209         else
 210             c = (unsigned char *)OPENSSL_realloc_clean(a->data,
 211                                                        a->length, w + 1);
 212         if (c == NULL) {
 213             ASN1err(ASN1_F_ASN1_BIT_STRING_SET_BIT, ERR_R_MALLOC_FAILURE);
 214             return 0;
 215         }
 216         if (w + 1 - a->length > 0)
 217             memset(c + a->length, 0, w + 1 - a->length);
 218         a->data = c;
 219         a->length = w + 1;
 220     }
 221     a->data[w] = ((a->data[w]) & iv) | v;
 222     while ((a->length > 0) && (a->data[a->length - 1] == 0))
 223         a->length--;
 224     return (1);
 225 }
 226
 227 int ASN1_BIT_STRING_get_bit(ASN1_BIT_STRING *a, int n)
 228 {
 229     int w, v;
 230
 231     w = n / 8;
 232     v = 1 << (7 - (n & 0x07));
 233     if ((a == NULL) || (a->length < (w + 1)) || (a->data == NULL))
 234         return (0);
 235     return ((a->data[w] & v) != 0);
 236 }