crypto/asn1/a_int.c

   1 /* crypto/asn1/a_int.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 "asn1.h"
  62
  63 /* ASN1err(ASN1_F_D2I_ASN1_INTEGER,ASN1_R_EXPECTING_AN_INTEGER);
  64  */
  65
  66 int i2d_ASN1_INTEGER(a,pp)
  67 ASN1_INTEGER *a;
  68 unsigned char **pp;
  69         {
  70         int pad=0,ret,r,i,t;
  71         unsigned char *p,*pt,*n,pb=0;
  72
  73         if ((a == NULL) || (a->data == NULL)) return(0);
  74         t=a->type;
  75         if (a->length == 0)
  76                 ret=1;
  77         else
  78                 {
  79                 ret=a->length;
  80                 i=a->data[0];
  81                 if ((t == V_ASN1_INTEGER) && (i > 127))
  82                         {
  83                         pad=1;
  84                         pb=0;
  85                         }
  86                 else if ((t == V_ASN1_NEG_INTEGER) && (i>128))
  87                         {
  88                         pad=1;
  89                         pb=0xFF;
  90                         }
  91                 ret+=pad;
  92                 }
  93         r=ASN1_object_size(0,ret,V_ASN1_INTEGER);
  94         if (pp == NULL) return(r);
  95         p= *pp;
  96
  97         ASN1_put_object(&p,0,ret,V_ASN1_INTEGER,V_ASN1_UNIVERSAL);
  98         if (pad) *(p++)=pb;
  99         if (a->length == 0)
 100                 *(p++)=0;
 101         else if (t == V_ASN1_INTEGER)
 102                 {
 103                 memcpy(p,a->data,(unsigned int)a->length);
 104                 p+=a->length;
 105                 }
 106         else
 107                 {
 108                 n=a->data;
 109                 pt=p;
 110                 for (i=a->length; i>0; i--)
 111                         *(p++)= (*(n++)^0xFF)+1;
 112                 if (!pad) *pt|=0x80;
 113                 }
 114
 115         *pp=p;
 116         return(r);
 117         }
 118
 119 ASN1_INTEGER *d2i_ASN1_INTEGER(a, pp, length)
 120 ASN1_INTEGER **a;
 121 unsigned char **pp;
 122 long length;
 123         {
 124         ASN1_INTEGER *ret=NULL;
 125         unsigned char *p,*to,*s;
 126         long len;
 127         int inf,tag,xclass;
 128         int i;
 129
 130         if ((a == NULL) || ((*a) == NULL))
 131                 {
 132                 if ((ret=ASN1_INTEGER_new()) == NULL) return(NULL);
 133                 ret->type=V_ASN1_INTEGER;
 134                 }
 135         else
 136                 ret=(*a);
 137
 138         p= *pp;
 139         inf=ASN1_get_object(&p,&len,&tag,&xclass,length);
 140         if (inf & 0x80)
 141                 {
 142                 i=ASN1_R_BAD_OBJECT_HEADER;
 143                 goto err;
 144                 }
 145
 146         if (tag != V_ASN1_INTEGER)
 147                 {
 148                 i=ASN1_R_EXPECTING_AN_INTEGER;
 149                 goto err;
 150                 }
 151
 152         /* We must Malloc stuff, even for 0 bytes otherwise it
 153          * signifies a missing NULL parameter. */
 154         s=(unsigned char *)Malloc((int)len+1);
 155         if (s == NULL)
 156                 {
 157                 i=ERR_R_MALLOC_FAILURE;
 158                 goto err;
 159                 }
 160         to=s;
 161         if (*p & 0x80) /* a negative number */
 162                 {
 163                 ret->type=V_ASN1_NEG_INTEGER;
 164                 if (*p == 0xff)
 165                         {
 166                         p++;
 167                         len--;
 168                         }
 169                 for (i=(int)len; i>0; i--)
 170                         *(to++)= (*(p++)^0xFF)+1;
 171                 }
 172         else
 173                 {
 174                 ret->type=V_ASN1_INTEGER;
 175                 if ((*p == 0) && (len != 1))
 176                         {
 177                         p++;
 178                         len--;
 179                         }
 180                 memcpy(s,p,(int)len);
 181                 p+=len;
 182                 }
 183
 184         if (ret->data != NULL) Free((char *)ret->data);
 185         ret->data=s;
 186         ret->length=(int)len;
 187         if (a != NULL) (*a)=ret;
 188         *pp=p;
 189         return(ret);
 190 err:
 191         ASN1err(ASN1_F_D2I_ASN1_INTEGER,i);
 192         if ((ret != NULL) && ((a == NULL) || (*a != ret)))
 193                 ASN1_INTEGER_free(ret);
 194         return(NULL);
 195         }
 196
 197 int ASN1_INTEGER_set(a,v)
 198 ASN1_INTEGER *a;
 199 long v;
 200         {
 201         int i,j,k;
 202         unsigned char buf[sizeof(long)+1];
 203         long d;
 204
 205         a->type=V_ASN1_INTEGER;
 206         if (a->length < (sizeof(long)+1))
 207                 {
 208                 if (a->data != NULL)
 209                         Free((char *)a->data);
 210                 if ((a->data=(unsigned char *)Malloc(sizeof(long)+1)) != NULL)
 211                         memset((char *)a->data,0,sizeof(long)+1);
 212                 }
 213         if (a->data == NULL)
 214                 {
 215                 ASN1err(ASN1_F_ASN1_INTEGER_SET,ERR_R_MALLOC_FAILURE);
 216                 return(0);
 217                 }
 218         d=v;
 219         if (d < 0)
 220                 {
 221                 d= -d;
 222                 a->type=V_ASN1_NEG_INTEGER;
 223                 }
 224
 225         for (i=0; i<sizeof(long); i++)
 226                 {
 227                 if (d == 0) break;
 228                 buf[i]=(int)d&0xff;
 229                 d>>=8;
 230                 }
 231         j=0;
 232         if (v < 0) a->data[j++]=0;
 233         for (k=i-1; k >=0; k--)
 234                 a->data[j++]=buf[k];
 235         a->length=j;
 236         return(1);
 237         }
 238
 239 long ASN1_INTEGER_get(a)
 240 ASN1_INTEGER *a;
 241         {
 242         int neg=0,i;
 243         long r=0;
 244
 245         if (a == NULL) return(0L);
 246         i=a->type;
 247         if (i == V_ASN1_NEG_INTEGER)
 248                 neg=1;
 249         else if (i != V_ASN1_INTEGER)
 250                 return(0);
 251
 252         if (a->length > sizeof(long))
 253                 {
 254                 /* hmm... a bit ugly */
 255                 return(0xffffffffL);
 256                 }
 257         if (a->data == NULL)
 258                 return(0);
 259
 260         for (i=0; i<a->length; i++)
 261                 {
 262                 r<<=8;
 263                 r|=(unsigned char)a->data[i];
 264                 }
 265         if (neg) r= -r;
 266         return(r);
 267         }
 268
 269 ASN1_INTEGER *BN_to_ASN1_INTEGER(bn,ai)
 270 BIGNUM *bn;
 271 ASN1_INTEGER *ai;
 272         {
 273         ASN1_INTEGER *ret;
 274         int len,j;
 275
 276         if (ai == NULL)
 277                 ret=ASN1_INTEGER_new();
 278         else
 279                 ret=ai;
 280         if (ret == NULL)
 281                 {
 282                 ASN1err(ASN1_F_BN_TO_ASN1_INTEGER,ASN1_R_ERROR_STACK);
 283                 goto err;
 284                 }
 285         ret->type=V_ASN1_INTEGER;
 286         j=BN_num_bits(bn);
 287         len=((j == 0)?0:((j/8)+1));
 288         ret->data=(unsigned char *)Malloc(len+4);
 289         ret->length=BN_bn2bin(bn,ret->data);
 290         return(ret);
 291 err:
 292         if (ret != ai) ASN1_INTEGER_free(ret);
 293         return(NULL);
 294         }
 295
 296 BIGNUM *ASN1_INTEGER_to_BN(ai,bn)
 297 ASN1_INTEGER *ai;
 298 BIGNUM *bn;
 299         {
 300         BIGNUM *ret;
 301
 302         if ((ret=BN_bin2bn(ai->data,ai->length,bn)) == NULL)
 303                 ASN1err(ASN1_F_ASN1_INTEGER_TO_BN,ASN1_R_BN_LIB);
 304         return(ret);
 305         }