crypto/heimdal-0.6.3/lib/asn1/gen_decode.c

   1 /*
   2  * Copyright (c) 1997 - 2001 Kungliga Tekniska Högskolan
   3  * (Royal Institute of Technology, Stockholm, Sweden).
   4  * All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  *
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  *
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in the
  15  *    documentation and/or other materials provided with the distribution.
  16  *
  17  * 3. Neither the name of the Institute nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  */
  33
  34 #include "gen_locl.h"
  35
  36 RCSID("$Id: gen_decode.c,v 1.18 2002/08/09 15:37:34 joda Exp $");
  37
  38 static void
  39 decode_primitive (const char *typename, const char *name)
  40 {
  41     fprintf (codefile,
  42              "e = decode_%s(p, len, %s, &l);\n"
  43              "FORW;\n",
  44              typename,
  45              name);
  46 }
  47
  48 static void
  49 decode_type (const char *name, const Type *t)
  50 {
  51     switch (t->type) {
  52     case TType:
  53 #if 0
  54         decode_type (name, t->symbol->type);
  55 #endif
  56         fprintf (codefile,
  57                  "e = decode_%s(p, len, %s, &l);\n"
  58                  "FORW;\n",
  59                  t->symbol->gen_name, name);
  60         break;
  61     case TInteger:
  62         if(t->members == NULL)
  63             decode_primitive ("integer", name);
  64         else {
  65             char *s;
  66             asprintf(&s, "(int*)%s", name);
  67             if(s == NULL)
  68                 errx (1, "out of memory");
  69             decode_primitive ("integer", s);
  70             free(s);
  71         }
  72         break;
  73     case TUInteger:
  74         decode_primitive ("unsigned", name);
  75         break;
  76     case TEnumerated:
  77         decode_primitive ("enumerated", name);
  78         break;
  79     case TOctetString:
  80         decode_primitive ("octet_string", name);
  81         break;
  82     case TOID :
  83         decode_primitive ("oid", name);
  84         break;
  85     case TBitString: {
  86         Member *m;
  87         int tag = -1;
  88         int pos;
  89
  90         fprintf (codefile,
  91                  "e = der_match_tag_and_length (p, len, UNIV, PRIM, UT_BitString,"
  92                  "&reallen, &l);\n"
  93                  "FORW;\n"
  94                  "if(len < reallen)\n"
  95                  "return ASN1_OVERRUN;\n"
  96                  "p++;\n"
  97                  "len--;\n"
  98                  "reallen--;\n"
  99                  "ret++;\n");
 100         pos = 0;
 101         for (m = t->members; m && tag != m->val; m = m->next) {
 102             while (m->val / 8 > pos / 8) {
 103                 fprintf (codefile,
 104                          "p++; len--; reallen--; ret++;\n");
 105                 pos += 8;
 106             }
 107             fprintf (codefile,
 108                      "%s->%s = (*p >> %d) & 1;\n",
 109                      name, m->gen_name, 7 - m->val % 8);
 110             if (tag == -1)
 111                 tag = m->val;
 112         }
 113         fprintf (codefile,
 114                  "p += reallen; len -= reallen; ret += reallen;\n");
 115         break;
 116     }
 117     case TSequence: {
 118         Member *m;
 119         int tag = -1;
 120
 121         if (t->members == NULL)
 122             break;
 123
 124         fprintf (codefile,
 125                  "e = der_match_tag_and_length (p, len, UNIV, CONS, UT_Sequence,"
 126                  "&reallen, &l);\n"
 127                  "FORW;\n"
 128                  "{\n"
 129                  "int dce_fix;\n"
 130                  "if((dce_fix = fix_dce(reallen, &len)) < 0)\n"
 131                  "return ASN1_BAD_FORMAT;\n");
 132
 133         for (m = t->members; m && tag != m->val; m = m->next) {
 134             char *s;
 135
 136             asprintf (&s, "%s(%s)->%s", m->optional ? "" : "&", name, m->gen_name);
 137             if (0 && m->type->type == TType){
 138                 if(m->optional)
 139                     fprintf (codefile,
 140                              "%s = malloc(sizeof(*%s));\n"
 141                              "if(%s == NULL) return ENOMEM;\n", s, s, s);
 142                 fprintf (codefile,
 143                          "e = decode_seq_%s(p, len, %d, %d, %s, &l);\n",
 144                          m->type->symbol->gen_name,
 145                          m->val,
 146                          m->optional,
 147                          s);
 148                 if(m->optional)
 149                     fprintf (codefile,
 150                              "if (e == ASN1_MISSING_FIELD) {\n"
 151                              "free(%s);\n"
 152                              "%s = NULL;\n"
 153                              "e = l = 0;\n"
 154                              "}\n",
 155                              s, s);
 156
 157                 fprintf (codefile, "FORW;\n");
 158
 159             }else{
 160                 fprintf (codefile, "{\n"
 161                          "size_t newlen, oldlen;\n\n"
 162                          "e = der_match_tag (p, len, CONTEXT, CONS, %d, &l);\n",
 163                          m->val);
 164                 fprintf (codefile,
 165                          "if (e)\n");
 166                 if(m->optional)
 167                     /* XXX should look at e */
 168                     fprintf (codefile,
 169                              "%s = NULL;\n", s);
 170                 else
 171                     fprintf (codefile,
 172                              "return e;\n");
 173                 fprintf (codefile,
 174                          "else {\n");
 175                 fprintf (codefile,
 176                          "p += l;\n"
 177                          "len -= l;\n"
 178                          "ret += l;\n"
 179                          "e = der_get_length (p, len, &newlen, &l);\n"
 180                          "FORW;\n"
 181                          "{\n"
 182
 183                          "int dce_fix;\n"
 184                          "oldlen = len;\n"
 185                          "if((dce_fix = fix_dce(newlen, &len)) < 0)"
 186                          "return ASN1_BAD_FORMAT;\n");
 187                 if (m->optional)
 188                     fprintf (codefile,
 189                              "%s = malloc(sizeof(*%s));\n"
 190                              "if(%s == NULL) return ENOMEM;\n", s, s, s);
 191                 decode_type (s, m->type);
 192                 fprintf (codefile,
 193                          "if(dce_fix){\n"
 194                          "e = der_match_tag_and_length (p, len, "
 195                          "(Der_class)0, (Der_type)0, 0, &reallen, &l);\n"
 196                          "FORW;\n"
 197                          "}else \n"
 198                          "len = oldlen - newlen;\n"
 199                          "}\n"
 200                          "}\n");
 201                 fprintf (codefile,
 202                          "}\n");
 203             }
 204             if (tag == -1)
 205                 tag = m->val;
 206             free (s);
 207         }
 208         fprintf(codefile,
 209                 "if(dce_fix){\n"
 210                 "e = der_match_tag_and_length (p, len, "
 211                 "(Der_class)0, (Der_type)0, 0, &reallen, &l);\n"
 212                 "FORW;\n"
 213                 "}\n"
 214                 "}\n");
 215
 216         break;
 217     }
 218     case TSequenceOf: {
 219         char *n;
 220
 221         fprintf (codefile,
 222                  "e = der_match_tag_and_length (p, len, UNIV, CONS, UT_Sequence,"
 223                  "&reallen, &l);\n"
 224                  "FORW;\n"
 225                  "if(len < reallen)\n"
 226                  "return ASN1_OVERRUN;\n"
 227                  "len = reallen;\n");
 228
 229         fprintf (codefile,
 230                  "{\n"
 231                  "size_t origlen = len;\n"
 232                  "int oldret = ret;\n"
 233                  "ret = 0;\n"
 234                  "(%s)->len = 0;\n"
 235                  "(%s)->val = NULL;\n"
 236                  "while(ret < origlen) {\n"
 237                  "(%s)->len++;\n"
 238                  "(%s)->val = realloc((%s)->val, sizeof(*((%s)->val)) * (%s)->len);\n",
 239                  name, name, name, name, name, name, name);
 240         asprintf (&n, "&(%s)->val[(%s)->len-1]", name, name);
 241         decode_type (n, t->subtype);
 242         fprintf (codefile,
 243                  "len = origlen - ret;\n"
 244                  "}\n"
 245                  "ret += oldret;\n"
 246                  "}\n");
 247         free (n);
 248         break;
 249     }
 250     case TGeneralizedTime:
 251         decode_primitive ("generalized_time", name);
 252         break;
 253     case TGeneralString:
 254         decode_primitive ("general_string", name);
 255         break;
 256     case TApplication:
 257         fprintf (codefile,
 258                  "e = der_match_tag_and_length (p, len, APPL, CONS, %d, "
 259                  "&reallen, &l);\n"
 260                  "FORW;\n"
 261                  "{\n"
 262                  "int dce_fix;\n"
 263                  "if((dce_fix = fix_dce(reallen, &len)) < 0)\n"
 264                  "return ASN1_BAD_FORMAT;\n",
 265                  t->application);
 266         decode_type (name, t->subtype);
 267         fprintf(codefile,
 268                 "if(dce_fix){\n"
 269                 "e = der_match_tag_and_length (p, len, "
 270                 "(Der_class)0, (Der_type)0, 0, &reallen, &l);\n"
 271                 "FORW;\n"
 272                 "}\n"
 273                 "}\n");
 274
 275         break;
 276     default :
 277         abort ();
 278     }
 279 }
 280
 281 void
 282 generate_type_decode (const Symbol *s)
 283 {
 284   fprintf (headerfile,
 285            "int    "
 286            "decode_%s(const unsigned char *, size_t, %s *, size_t *);\n",
 287            s->gen_name, s->gen_name);
 288
 289   fprintf (codefile, "#define FORW "
 290            "if(e) goto fail; "
 291            "p += l; "
 292            "len -= l; "
 293            "ret += l\n\n");
 294
 295
 296   fprintf (codefile, "int\n"
 297            "decode_%s(const unsigned char *p,"
 298            " size_t len, %s *data, size_t *size)\n"
 299            "{\n",
 300            s->gen_name, s->gen_name);
 301
 302   switch (s->type->type) {
 303   case TInteger:
 304   case TUInteger:
 305   case TOctetString:
 306   case TOID:
 307   case TGeneralizedTime:
 308   case TGeneralString:
 309   case TBitString:
 310   case TSequence:
 311   case TSequenceOf:
 312   case TApplication:
 313   case TType:
 314     fprintf (codefile,
 315              "size_t ret = 0, reallen;\n"
 316              "size_t l;\n"
 317              "int e;\n\n");
 318     fprintf (codefile, "memset(data, 0, sizeof(*data));\n");
 319     fprintf (codefile, "reallen = 0;\n"); /* hack to avoid `unused variable' */
 320
 321     decode_type ("data", s->type);
 322     fprintf (codefile,
 323              "if(size) *size = ret;\n"
 324              "return 0;\n");
 325     fprintf (codefile,
 326              "fail:\n"
 327              "free_%s(data);\n"
 328              "return e;\n",
 329              s->gen_name);
 330     break;
 331   default:
 332     abort ();
 333   }
 334   fprintf (codefile, "}\n\n");
 335 }
 336
 337 void
 338 generate_seq_type_decode (const Symbol *s)
 339 {
 340     fprintf (headerfile,
 341              "int decode_seq_%s(const unsigned char *, size_t, int, int, "
 342              "%s *, size_t *);\n",
 343              s->gen_name, s->gen_name);
 344
 345     fprintf (codefile, "int\n"
 346              "decode_seq_%s(const unsigned char *p, size_t len, int tag, "
 347              "int optional, %s *data, size_t *size)\n"
 348              "{\n",
 349              s->gen_name, s->gen_name);
 350
 351     fprintf (codefile,
 352              "size_t newlen, oldlen;\n"
 353              "size_t l, ret = 0;\n"
 354              "int e;\n"
 355              "int dce_fix;\n");
 356
 357     fprintf (codefile,
 358              "e = der_match_tag(p, len, CONTEXT, CONS, tag, &l);\n"
 359              "if (e)\n"
 360              "return e;\n");
 361     fprintf (codefile,
 362              "p += l;\n"
 363              "len -= l;\n"
 364              "ret += l;\n"
 365              "e = der_get_length(p, len, &newlen, &l);\n"
 366              "if (e)\n"
 367              "return e;\n"
 368              "p += l;\n"
 369              "len -= l;\n"
 370              "ret += l;\n"
 371              "oldlen = len;\n"
 372              "if ((dce_fix = fix_dce(newlen, &len)) < 0)\n"
 373              "return ASN1_BAD_FORMAT;\n"
 374              "e = decode_%s(p, len, data, &l);\n"
 375              "if (e)\n"
 376              "return e;\n"
 377              "p += l;\n"
 378              "len -= l;\n"
 379              "ret += l;\n"
 380              "if (dce_fix) {\n"
 381              "size_t reallen;\n\n"
 382              "e = der_match_tag_and_length(p, len, "
 383              "(Der_class)0, (Der_type)0, 0, &reallen, &l);\n"
 384              "if (e)\n"
 385              "return e;\n"
 386              "ret += l;\n"
 387              "}\n",
 388              s->gen_name);
 389     fprintf (codefile,
 390              "if(size) *size = ret;\n"
 391              "return 0;\n");
 392
 393     fprintf (codefile, "}\n\n");
 394 }