crypto/openssl/crypto/bn/bn_print.c

   1 /* crypto/bn/bn_print.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 <ctype.h>
  61 #include "cryptlib.h"
  62 #include <openssl/buffer.h>
  63 #include "bn_lcl.h"
  64
  65 static const char Hex[]="0123456789ABCDEF";
  66
  67 /* Must 'OPENSSL_free' the returned data */
  68 char *BN_bn2hex(const BIGNUM *a)
  69         {
  70         int i,j,v,z=0;
  71         char *buf;
  72         char *p;
  73
  74         buf=(char *)OPENSSL_malloc(a->top*BN_BYTES*2+2);
  75         if (buf == NULL)
  76                 {
  77                 BNerr(BN_F_BN_BN2HEX,ERR_R_MALLOC_FAILURE);
  78                 goto err;
  79                 }
  80         p=buf;
  81         if (a->neg) *(p++)='-';
  82         if (BN_is_zero(a)) *(p++)='0';
  83         for (i=a->top-1; i >=0; i--)
  84                 {
  85                 for (j=BN_BITS2-8; j >= 0; j-=8)
  86                         {
  87                         /* strip leading zeros */
  88                         v=((int)(a->d[i]>>(long)j))&0xff;
  89                         if (z || (v != 0))
  90                                 {
  91                                 *(p++)=Hex[v>>4];
  92                                 *(p++)=Hex[v&0x0f];
  93                                 z=1;
  94                                 }
  95                         }
  96                 }
  97         *p='\0';
  98 err:
  99         return(buf);
 100         }
 101
 102 /* Must 'OPENSSL_free' the returned data */
 103 char *BN_bn2dec(const BIGNUM *a)
 104         {
 105         int i=0,num, ok = 0;
 106         char *buf=NULL;
 107         char *p;
 108         BIGNUM *t=NULL;
 109         BN_ULONG *bn_data=NULL,*lp;
 110
 111         /* get an upper bound for the length of the decimal integer
 112          * num <= (BN_num_bits(a) + 1) * log(2)
 113          *     <= 3 * BN_num_bits(a) * 0.1001 + log(2) + 1     (rounding error)
 114          *     <= BN_num_bits(a)/10 + BN_num_bits/1000 + 1 + 1
 115          */
 116         i=BN_num_bits(a)*3;
 117         num=(i/10+i/1000+1)+1;
 118         bn_data=(BN_ULONG *)OPENSSL_malloc((num/BN_DEC_NUM+1)*sizeof(BN_ULONG));
 119         buf=(char *)OPENSSL_malloc(num+3);
 120         if ((buf == NULL) || (bn_data == NULL))
 121                 {
 122                 BNerr(BN_F_BN_BN2DEC,ERR_R_MALLOC_FAILURE);
 123                 goto err;
 124                 }
 125         if ((t=BN_dup(a)) == NULL) goto err;
 126
 127 #define BUF_REMAIN (num+3 - (size_t)(p - buf))
 128         p=buf;
 129         lp=bn_data;
 130         if (BN_is_zero(t))
 131                 {
 132                 *(p++)='0';
 133                 *(p++)='\0';
 134                 }
 135         else
 136                 {
 137                 if (BN_is_negative(t))
 138                         *p++ = '-';
 139
 140                 i=0;
 141                 while (!BN_is_zero(t))
 142                         {
 143                         *lp=BN_div_word(t,BN_DEC_CONV);
 144                         lp++;
 145                         }
 146                 lp--;
 147                 /* We now have a series of blocks, BN_DEC_NUM chars
 148                  * in length, where the last one needs truncation.
 149                  * The blocks need to be reversed in order. */
 150                 BIO_snprintf(p,BUF_REMAIN,BN_DEC_FMT1,*lp);
 151                 while (*p) p++;
 152                 while (lp != bn_data)
 153                         {
 154                         lp--;
 155                         BIO_snprintf(p,BUF_REMAIN,BN_DEC_FMT2,*lp);
 156                         while (*p) p++;
 157                         }
 158                 }
 159         ok = 1;
 160 err:
 161         if (bn_data != NULL) OPENSSL_free(bn_data);
 162         if (t != NULL) BN_free(t);
 163         if (!ok && buf)
 164                 {
 165                 OPENSSL_free(buf);
 166                 buf = NULL;
 167                 }
 168
 169         return(buf);
 170         }
 171
 172 int BN_hex2bn(BIGNUM **bn, const char *a)
 173         {
 174         BIGNUM *ret=NULL;
 175         BN_ULONG l=0;
 176         int neg=0,h,m,i,j,k,c;
 177         int num;
 178
 179         if ((a == NULL) || (*a == '\0')) return(0);
 180
 181         if (*a == '-') { neg=1; a++; }
 182
 183         for (i=0; isxdigit((unsigned char) a[i]); i++)
 184                 ;
 185
 186         num=i+neg;
 187         if (bn == NULL) return(num);
 188
 189         /* a is the start of the hex digits, and it is 'i' long */
 190         if (*bn == NULL)
 191                 {
 192                 if ((ret=BN_new()) == NULL) return(0);
 193                 }
 194         else
 195                 {
 196                 ret= *bn;
 197                 BN_zero(ret);
 198                 }
 199
 200         /* i is the number of hex digests; */
 201         if (bn_expand(ret,i*4) == NULL) goto err;
 202
 203         j=i; /* least significant 'hex' */
 204         m=0;
 205         h=0;
 206         while (j > 0)
 207                 {
 208                 m=((BN_BYTES*2) <= j)?(BN_BYTES*2):j;
 209                 l=0;
 210                 for (;;)
 211                         {
 212                         c=a[j-m];
 213                         if ((c >= '0') && (c <= '9')) k=c-'0';
 214                         else if ((c >= 'a') && (c <= 'f')) k=c-'a'+10;
 215                         else if ((c >= 'A') && (c <= 'F')) k=c-'A'+10;
 216                         else k=0; /* paranoia */
 217                         l=(l<<4)|k;
 218
 219                         if (--m <= 0)
 220                                 {
 221                                 ret->d[h++]=l;
 222                                 break;
 223                                 }
 224                         }
 225                 j-=(BN_BYTES*2);
 226                 }
 227         ret->top=h;
 228         bn_correct_top(ret);
 229         ret->neg=neg;
 230
 231         *bn=ret;
 232         bn_check_top(ret);
 233         return(num);
 234 err:
 235         if (*bn == NULL) BN_free(ret);
 236         return(0);
 237         }
 238
 239 int BN_dec2bn(BIGNUM **bn, const char *a)
 240         {
 241         BIGNUM *ret=NULL;
 242         BN_ULONG l=0;
 243         int neg=0,i,j;
 244         int num;
 245
 246         if ((a == NULL) || (*a == '\0')) return(0);
 247         if (*a == '-') { neg=1; a++; }
 248
 249         for (i=0; isdigit((unsigned char) a[i]); i++)
 250                 ;
 251
 252         num=i+neg;
 253         if (bn == NULL) return(num);
 254
 255         /* a is the start of the digits, and it is 'i' long.
 256          * We chop it into BN_DEC_NUM digits at a time */
 257         if (*bn == NULL)
 258                 {
 259                 if ((ret=BN_new()) == NULL) return(0);
 260                 }
 261         else
 262                 {
 263                 ret= *bn;
 264                 BN_zero(ret);
 265                 }
 266
 267         /* i is the number of digests, a bit of an over expand; */
 268         if (bn_expand(ret,i*4) == NULL) goto err;
 269
 270         j=BN_DEC_NUM-(i%BN_DEC_NUM);
 271         if (j == BN_DEC_NUM) j=0;
 272         l=0;
 273         while (*a)
 274                 {
 275                 l*=10;
 276                 l+= *a-'0';
 277                 a++;
 278                 if (++j == BN_DEC_NUM)
 279                         {
 280                         BN_mul_word(ret,BN_DEC_CONV);
 281                         BN_add_word(ret,l);
 282                         l=0;
 283                         j=0;
 284                         }
 285                 }
 286         ret->neg=neg;
 287
 288         bn_correct_top(ret);
 289         *bn=ret;
 290         bn_check_top(ret);
 291         return(num);
 292 err:
 293         if (*bn == NULL) BN_free(ret);
 294         return(0);
 295         }
 296
 297 #ifndef OPENSSL_NO_BIO
 298 #ifndef OPENSSL_NO_FP_API
 299 int BN_print_fp(FILE *fp, const BIGNUM *a)
 300         {
 301         BIO *b;
 302         int ret;
 303
 304         if ((b=BIO_new(BIO_s_file())) == NULL)
 305                 return(0);
 306         BIO_set_fp(b,fp,BIO_NOCLOSE);
 307         ret=BN_print(b,a);
 308         BIO_free(b);
 309         return(ret);
 310         }
 311 #endif
 312
 313 int BN_print(BIO *bp, const BIGNUM *a)
 314         {
 315         int i,j,v,z=0;
 316         int ret=0;
 317
 318         if ((a->neg) && (BIO_write(bp,"-",1) != 1)) goto end;
 319         if (BN_is_zero(a) && (BIO_write(bp,"0",1) != 1)) goto end;
 320         for (i=a->top-1; i >=0; i--)
 321                 {
 322                 for (j=BN_BITS2-4; j >= 0; j-=4)
 323                         {
 324                         /* strip leading zeros */
 325                         v=((int)(a->d[i]>>(long)j))&0x0f;
 326                         if (z || (v != 0))
 327                                 {
 328                                 if (BIO_write(bp,&(Hex[v]),1) != 1)
 329                                         goto end;
 330                                 z=1;
 331                                 }
 332                         }
 333                 }
 334         ret=1;
 335 end:
 336         return(ret);
 337         }
 338 #endif