crypto/evp/encode.c

   1 /* crypto/evp/encode.c */
   2 /* Copyright (C) 1995-1997 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 "evp.h"
  62
  63 #define conv_bin2ascii(a)       (data_bin2ascii[(a)&0x3f])
  64 #define conv_ascii2bin(a)       (data_ascii2bin[(a)&0x7f])
  65
  66 /* 64 char lines
  67  * pad input with 0
  68  * left over chars are set to =
  69  * 1 byte  => xx==
  70  * 2 bytes => xxx=
  71  * 3 bytes => xxxx
  72  */
  73 #define BIN_PER_LINE    (64/4*3)
  74 #define CHUNKS_PER_LINE (64/4)
  75 #define CHAR_PER_LINE   (64+1)
  76
  77 static unsigned char data_bin2ascii[65]="ABCDEFGHIJKLMNOPQRSTUVWXYZ\
  78 abcdefghijklmnopqrstuvwxyz0123456789+/";
  79
  80 /* 0xF0 is a EOLN
  81  * 0xF1 is ignore but next needs to be 0xF0 (for \r\n processing).
  82  * 0xF2 is EOF
  83  * 0xE0 is ignore at start of line.
  84  * 0xFF is error
  85  */
  86
  87 #define B64_EOLN                0xF0
  88 #define B64_CR                  0xF1
  89 #define B64_EOF                 0xF2
  90 #define B64_WS                  0xE0
  91 #define B64_ERROR               0xFF
  92 #define B64_NOT_BASE64(a)       (((a)|0x13) == 0xF3)
  93
  94 static unsigned char data_ascii2bin[128]={
  95         0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
  96         0xFF,0xE0,0xF0,0xFF,0xFF,0xF1,0xFF,0xFF,
  97         0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
  98         0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
  99         0xE0,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
 100         0xFF,0xFF,0xFF,0x3E,0xFF,0xF2,0xFF,0x3F,
 101         0x34,0x35,0x36,0x37,0x38,0x39,0x3A,0x3B,
 102         0x3C,0x3D,0xFF,0xFF,0xFF,0x00,0xFF,0xFF,
 103         0xFF,0x00,0x01,0x02,0x03,0x04,0x05,0x06,
 104         0x07,0x08,0x09,0x0A,0x0B,0x0C,0x0D,0x0E,
 105         0x0F,0x10,0x11,0x12,0x13,0x14,0x15,0x16,
 106         0x17,0x18,0x19,0xFF,0xFF,0xFF,0xFF,0xFF,
 107         0xFF,0x1A,0x1B,0x1C,0x1D,0x1E,0x1F,0x20,
 108         0x21,0x22,0x23,0x24,0x25,0x26,0x27,0x28,
 109         0x29,0x2A,0x2B,0x2C,0x2D,0x2E,0x2F,0x30,
 110         0x31,0x32,0x33,0xFF,0xFF,0xFF,0xFF,0xFF,
 111         };
 112
 113 void EVP_EncodeInit(ctx)
 114 EVP_ENCODE_CTX *ctx;
 115         {
 116         ctx->length=48;
 117         ctx->num=0;
 118         ctx->line_num=0;
 119         }
 120
 121 void EVP_EncodeUpdate(ctx,out,outl,in,inl)
 122 EVP_ENCODE_CTX *ctx;
 123 unsigned char *out;
 124 int *outl;
 125 unsigned char *in;
 126 int inl;
 127         {
 128         int i,j;
 129         unsigned int total=0;
 130
 131         *outl=0;
 132         if (inl == 0) return;
 133         if ((ctx->num+inl) < ctx->length)
 134                 {
 135                 memcpy(&(ctx->enc_data[ctx->num]),in,inl);
 136                 ctx->num+=inl;
 137                 return;
 138                 }
 139         if (ctx->num != 0)
 140                 {
 141                 i=ctx->length-ctx->num;
 142                 memcpy(&(ctx->enc_data[ctx->num]),in,i);
 143                 in+=i;
 144                 inl-=i;
 145                 j=EVP_EncodeBlock(out,ctx->enc_data,ctx->length);
 146                 ctx->num=0;
 147                 out+=j;
 148                 *(out++)='\n';
 149                 *out='\0';
 150                 total=j+1;
 151                 }
 152         while (inl >= ctx->length)
 153                 {
 154                 j=EVP_EncodeBlock(out,in,ctx->length);
 155                 in+=ctx->length;
 156                 inl-=ctx->length;
 157                 out+=j;
 158                 *(out++)='\n';
 159                 *out='\0';
 160                 total+=j+1;
 161                 }
 162         if (inl != 0)
 163                 memcpy(&(ctx->enc_data[0]),in,inl);
 164         ctx->num=inl;
 165         *outl=total;
 166         }
 167
 168 void EVP_EncodeFinal(ctx,out,outl)
 169 EVP_ENCODE_CTX *ctx;
 170 unsigned char *out;
 171 int *outl;
 172         {
 173         unsigned int ret=0;
 174
 175         if (ctx->num != 0)
 176                 {
 177                 ret=EVP_EncodeBlock(out,ctx->enc_data,ctx->num);
 178                 out[ret++]='\n';
 179                 out[ret]='\0';
 180                 ctx->num=0;
 181                 }
 182         *outl=ret;
 183         }
 184
 185 int EVP_EncodeBlock(t,f,dlen)
 186 unsigned char *t,*f;
 187 int dlen;
 188         {
 189         int i,ret=0;
 190         unsigned long l;
 191
 192         for (i=dlen; i > 0; i-=3)
 193                 {
 194                 if (i >= 3)
 195                         {
 196                         l=      (((unsigned long)f[0])<<16L)|
 197                                 (((unsigned long)f[1])<< 8L)|f[2];
 198                         *(t++)=conv_bin2ascii(l>>18L);
 199                         *(t++)=conv_bin2ascii(l>>12L);
 200                         *(t++)=conv_bin2ascii(l>> 6L);
 201                         *(t++)=conv_bin2ascii(l     );
 202                         }
 203                 else
 204                         {
 205                         l=((unsigned long)f[0])<<16L;
 206                         if (i == 2) l|=((unsigned long)f[1]<<8L);
 207
 208                         *(t++)=conv_bin2ascii(l>>18L);
 209                         *(t++)=conv_bin2ascii(l>>12L);
 210                         *(t++)=(i == 1)?'=':conv_bin2ascii(l>> 6L);
 211                         *(t++)='=';
 212                         }
 213                 ret+=4;
 214                 f+=3;
 215                 }
 216
 217         *t='\0';
 218         return(ret);
 219         }
 220
 221 void EVP_DecodeInit(ctx)
 222 EVP_ENCODE_CTX *ctx;
 223         {
 224         ctx->length=30;
 225         ctx->num=0;
 226         ctx->line_num=0;
 227         }
 228
 229 /* -1 for error
 230  *  0 for last line
 231  *  1 for full line
 232  */
 233 int EVP_DecodeUpdate(ctx,out,outl,in,inl)
 234 EVP_ENCODE_CTX *ctx;
 235 unsigned char *out;
 236 int *outl;
 237 unsigned char *in;
 238 int inl;
 239         {
 240         int seof= -1,eof=0,rv= -1,ret=0,i,v,tmp,n,ln,tmp2;
 241         unsigned char *d;
 242
 243         n=ctx->num;
 244         d=ctx->enc_data;
 245         ln=ctx->line_num;
 246
 247         /* last line of input. */
 248         if ((inl == 0) || ((n == 0) && (conv_ascii2bin(in[0]) == B64_EOF)))
 249                 { rv=0; goto end; }
 250
 251         /* We parse the input data */
 252         for (i=0; i<inl; i++)
 253                 {
 254                 /* If the current line is > 80 characters, scream alot */
 255                 if (ln >= 80) { rv= -1; goto end; }
 256
 257                 /* Get char and put it into the buffer */
 258                 tmp= *(in++);
 259                 v=conv_ascii2bin(tmp);
 260                 /* only save the good data :-) */
 261                 if (!B64_NOT_BASE64(v))
 262                         {
 263                         d[n++]=tmp;
 264                         ln++;
 265                         }
 266                 else if (v == B64_ERROR)
 267                         {
 268                         rv= -1;
 269                         goto end;
 270                         }
 271
 272                 /* have we seen a '=' which is 'definitly' the last
 273                  * input line.  seof will point to the character that
 274                  * holds it. and eof will hold how many characters to
 275                  * chop off. */
 276                 if (tmp == '=')
 277                         {
 278                         if (seof == -1) seof=n;
 279                         eof++;
 280                         }
 281
 282                 /* eoln */
 283                 if (v == B64_EOLN) ln=0;
 284
 285                 /* If we are at the end of input and it looks like a
 286                  * line, process it. */
 287                 if (((i+1) == inl) && (((n&3) == 0) || eof))
 288                         v=B64_EOF;
 289
 290                 if ((v == B64_EOF) || (n >= 64))
 291                         {
 292                         tmp2=v;
 293                         if (n > 0)
 294                                 {
 295                                 v=EVP_DecodeBlock(out,d,n);
 296                                 if (v < 0) { rv=0; goto end; }
 297                                 n=0;
 298                                 ret+=(v-eof);
 299                                 }
 300                         else
 301                                 {
 302                                 eof=1;
 303                                 v=0;
 304                                 }
 305
 306                         /* This is the case where we have had a short
 307                          * but valid input line */
 308                         if ((v < ctx->length) && eof)
 309                                 {
 310                                 rv=0;
 311                                 goto end;
 312                                 }
 313                         else
 314                                 ctx->length=v;
 315
 316                         if (seof >= 0) { rv=0; goto end; }
 317                         out+=v;
 318                         }
 319                 }
 320         rv=1;
 321 end:
 322         *outl=ret;
 323         ctx->num=n;
 324         ctx->line_num=ln;
 325         return(rv);
 326         }
 327
 328 int EVP_DecodeBlock(t,f,n)
 329 unsigned char *t,*f;
 330 int n;
 331         {
 332         int i,ret=0,a,b,c,d;
 333         unsigned long l;
 334
 335         /* trim white space from the start of the line. */
 336         while ((conv_ascii2bin(*f) == B64_WS) && (n > 0))
 337                 {
 338                 f++;
 339                 n--;
 340                 }
 341
 342         /* strip off stuff at the end of the line
 343          * ascii2bin values B64_WS, B64_EOLN, B64_EOLN and B64_EOF */
 344         while ((n > 3) && (B64_NOT_BASE64(conv_ascii2bin(f[n-1]))))
 345                 n--;
 346
 347         if (n%4 != 0) return(-1);
 348
 349         for (i=0; i<n; i+=4)
 350                 {
 351                 a=conv_ascii2bin(*(f++));
 352                 b=conv_ascii2bin(*(f++));
 353                 c=conv_ascii2bin(*(f++));
 354                 d=conv_ascii2bin(*(f++));
 355                 if (    (a & 0x80) || (b & 0x80) ||
 356                         (c & 0x80) || (d & 0x80))
 357                         return(-1);
 358                 l=(     (((unsigned long)a)<<18L)|
 359                         (((unsigned long)b)<<12L)|
 360                         (((unsigned long)c)<< 6L)|
 361                         (((unsigned long)d)     ));
 362                 *(t++)=(unsigned char)(l>>16L)&0xff;
 363                 *(t++)=(unsigned char)(l>> 8L)&0xff;
 364                 *(t++)=(unsigned char)(l     )&0xff;
 365                 ret+=3;
 366                 }
 367         return(ret);
 368         }
 369
 370 int EVP_DecodeFinal(ctx,out,outl)
 371 EVP_ENCODE_CTX *ctx;
 372 unsigned char *out;
 373 int *outl;
 374         {
 375         int i;
 376
 377         *outl=0;
 378         if (ctx->num != 0)
 379                 {
 380                 i=EVP_DecodeBlock(out,ctx->enc_data,ctx->num);
 381                 if (i < 0) return(-1);
 382                 ctx->num=0;
 383                 *outl=i;
 384                 return(1);
 385                 }
 386         else
 387                 return(1);
 388         }
 389
 390 #ifdef undef
 391 int EVP_DecodeValid(buf,len)
 392 unsigned char *buf;
 393 int len;
 394         {
 395         int i,num=0,bad=0;
 396
 397         if (len == 0) return(-1);
 398         while (conv_ascii2bin(*buf) == B64_WS)
 399                 {
 400                 buf++;
 401                 len--;
 402                 if (len == 0) return(-1);
 403                 }
 404
 405         for (i=len; i >= 4; i-=4)
 406                 {
 407                 if (    (conv_ascii2bin(buf[0]) >= 0x40) ||
 408                         (conv_ascii2bin(buf[1]) >= 0x40) ||
 409                         (conv_ascii2bin(buf[2]) >= 0x40) ||
 410                         (conv_ascii2bin(buf[3]) >= 0x40))
 411                         return(-1);
 412                 buf+=4;
 413                 num+=1+(buf[2] != '=')+(buf[3] != '=');
 414                 }
 415         if ((i == 1) && (conv_ascii2bin(buf[0]) == B64_EOLN))
 416                 return(num);
 417         if ((i == 2) && (conv_ascii2bin(buf[0]) == B64_EOLN) &&
 418                 (conv_ascii2bin(buf[0]) == B64_EOLN))
 419                 return(num);
 420         return(1);
 421         }
 422 #endif