lib/asn1/gen_decode.c

   1 /*
   2  * Copyright (c) 1997 - 2006 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 #include "lex.h"
  36
  37 RCSID("$Id$");
  38
  39 static void
  40 decode_primitive (const char *typename, const char *name, const char *forwstr)
  41 {
  42 #if 0
  43     fprintf (codefile,
  44              "e = decode_%s(p, len, %s, &l);\n"
  45              "%s;\n",
  46              typename,
  47              name,
  48              forwstr);
  49 #else
  50     fprintf (codefile,
  51              "e = der_get_%s(p, len, %s, &l);\n"
  52              "if(e) %s;\np += l; len -= l; ret += l;\n",
  53              typename,
  54              name,
  55              forwstr);
  56 #endif
  57 }
  58
  59 static void
  60 find_tag (const Type *t,
  61           Der_class *cl, Der_type *ty, unsigned *tag)
  62 {
  63     switch (t->type) {
  64     case TBitString:
  65         *cl  = ASN1_C_UNIV;
  66         *ty  = PRIM;
  67         *tag = UT_BitString;
  68         break;
  69     case TBoolean:
  70         *cl  = ASN1_C_UNIV;
  71         *ty  = PRIM;
  72         *tag = UT_Boolean;
  73         break;
  74     case TChoice:
  75         errx(1, "Cannot have recursive CHOICE");
  76     case TEnumerated:
  77         *cl  = ASN1_C_UNIV;
  78         *ty  = PRIM;
  79         *tag = UT_Enumerated;
  80         break;
  81     case TGeneralString:
  82         *cl  = ASN1_C_UNIV;
  83         *ty  = PRIM;
  84         *tag = UT_GeneralString;
  85         break;
  86     case TTeletexString:
  87         *cl  = ASN1_C_UNIV;
  88         *ty  = PRIM;
  89         *tag = UT_TeletexString;
  90         break;
  91     case TGeneralizedTime:
  92         *cl  = ASN1_C_UNIV;
  93         *ty  = PRIM;
  94         *tag = UT_GeneralizedTime;
  95         break;
  96     case TIA5String:
  97         *cl  = ASN1_C_UNIV;
  98         *ty  = PRIM;
  99         *tag = UT_IA5String;
 100         break;
 101     case TInteger:
 102         *cl  = ASN1_C_UNIV;
 103         *ty  = PRIM;
 104         *tag = UT_Integer;
 105         break;
 106     case TNull:
 107         *cl  = ASN1_C_UNIV;
 108         *ty  = PRIM;
 109         *tag = UT_Null;
 110         break;
 111     case TOID:
 112         *cl  = ASN1_C_UNIV;
 113         *ty  = PRIM;
 114         *tag = UT_OID;
 115         break;
 116     case TOctetString:
 117         *cl  = ASN1_C_UNIV;
 118         *ty  = PRIM;
 119         *tag = UT_OctetString;
 120         break;
 121     case TPrintableString:
 122         *cl  = ASN1_C_UNIV;
 123         *ty  = PRIM;
 124         *tag = UT_PrintableString;
 125         break;
 126     case TSequence:
 127     case TSequenceOf:
 128         *cl  = ASN1_C_UNIV;
 129         *ty  = CONS;
 130         *tag = UT_Sequence;
 131         break;
 132     case TSet:
 133     case TSetOf:
 134         *cl  = ASN1_C_UNIV;
 135         *ty  = CONS;
 136         *tag = UT_Set;
 137         break;
 138     case TTag:
 139         *cl  = t->tag.tagclass;
 140         *ty  = is_primitive_type(t->subtype->type) ? PRIM : CONS;
 141         *tag = t->tag.tagvalue;
 142         break;
 143     case TType:
 144         if ((t->symbol->stype == Stype && t->symbol->type == NULL)
 145             || t->symbol->stype == SUndefined) {
 146             error_message("%s is imported or still undefined, "
 147                           " can't generate tag checking data in CHOICE "
 148                           "without this information",
 149                           t->symbol->name);
 150             exit(1);
 151         }
 152         find_tag(t->symbol->type, cl, ty, tag);
 153         return;
 154     case TUTCTime:
 155         *cl  = ASN1_C_UNIV;
 156         *ty  = PRIM;
 157         *tag = UT_UTCTime;
 158         break;
 159     case TUTF8String:
 160         *cl  = ASN1_C_UNIV;
 161         *ty  = PRIM;
 162         *tag = UT_UTF8String;
 163         break;
 164     case TBMPString:
 165         *cl  = ASN1_C_UNIV;
 166         *ty  = PRIM;
 167         *tag = UT_BMPString;
 168         break;
 169     case TUniversalString:
 170         *cl  = ASN1_C_UNIV;
 171         *ty  = PRIM;
 172         *tag = UT_UniversalString;
 173         break;
 174     case TVisibleString:
 175         *cl  = ASN1_C_UNIV;
 176         *ty  = PRIM;
 177         *tag = UT_VisibleString;
 178         break;
 179     default:
 180         abort();
 181     }
 182 }
 183
 184 static void
 185 range_check(const char *name,
 186             const char *length,
 187             const char *forwstr,
 188             struct range *r)
 189 {
 190     if (r->min == r->max + 2 || r->min < r->max)
 191         fprintf (codefile,
 192                  "if ((%s)->%s > %d) {\n"
 193                  "e = ASN1_MAX_CONSTRAINT; %s;\n"
 194                  "}\n",
 195                  name, length, r->max, forwstr);
 196     if (r->min - 1 == r->max || r->min < r->max)
 197         fprintf (codefile,
 198                  "if ((%s)->%s < %d) {\n"
 199                  "e = ASN1_MIN_CONSTRAINT; %s;\n"
 200                  "}\n",
 201                  name, length, r->min, forwstr);
 202     if (r->max == r->min)
 203         fprintf (codefile,
 204                  "if ((%s)->%s != %d) {\n"
 205                  "e = ASN1_EXACT_CONSTRAINT; %s;\n"
 206                  "}\n",
 207                  name, length, r->min, forwstr);
 208 }
 209
 210 static int
 211 decode_type (const char *name, const Type *t, int optional,
 212              const char *forwstr, const char *tmpstr, const char *dertype)
 213 {
 214     switch (t->type) {
 215     case TType: {
 216         if (optional)
 217             fprintf(codefile,
 218                     "%s = calloc(1, sizeof(*%s));\n"
 219                     "if (%s == NULL) %s;\n",
 220                     name, name, name, forwstr);
 221         fprintf (codefile,
 222                  "e = decode_%s(p, len, %s, &l);\n",
 223                  t->symbol->gen_name, name);
 224         if (optional) {
 225             fprintf (codefile,
 226                      "if(e) {\n"
 227                      "free(%s);\n"
 228                      "%s = NULL;\n"
 229                      "} else {\n"
 230                      "p += l; len -= l; ret += l;\n"
 231                      "}\n",
 232                      name, name);
 233         } else {
 234             fprintf (codefile,
 235                      "if(e) %s;\n",
 236                      forwstr);
 237             fprintf (codefile,
 238                      "p += l; len -= l; ret += l;\n");
 239         }
 240         break;
 241     }
 242     case TInteger:
 243         if(t->members) {
 244             fprintf(codefile,
 245                     "{\n"
 246                     "int enumint;\n");
 247             decode_primitive ("integer", "&enumint", forwstr);
 248             fprintf(codefile,
 249                     "*%s = enumint;\n"
 250                     "}\n",
 251                     name);
 252         } else if (t->range == NULL) {
 253             decode_primitive ("heim_integer", name, forwstr);
 254         } else if (t->range->min == INT_MIN && t->range->max == INT_MAX) {
 255             decode_primitive ("integer", name, forwstr);
 256         } else if (t->range->min == 0 && t->range->max == UINT_MAX) {
 257             decode_primitive ("unsigned", name, forwstr);
 258         } else if (t->range->min == 0 && t->range->max == INT_MAX) {
 259             decode_primitive ("unsigned", name, forwstr);
 260         } else
 261             errx(1, "%s: unsupported range %d -> %d",
 262                  name, t->range->min, t->range->max);
 263         break;
 264     case TBoolean:
 265       decode_primitive ("boolean", name, forwstr);
 266       break;
 267     case TEnumerated:
 268         decode_primitive ("enumerated", name, forwstr);
 269         break;
 270     case TOctetString:
 271         if (dertype) {
 272             fprintf(codefile,
 273                     "if (%s == CONS) {\n",
 274                     dertype);
 275             decode_primitive("octet_string_ber", name, forwstr);
 276             fprintf(codefile,
 277                     "} else {\n");
 278         }
 279         decode_primitive ("octet_string", name, forwstr);
 280         if (dertype)
 281             fprintf(codefile, "}\n");
 282         if (t->range)
 283             range_check(name, "length", forwstr, t->range);
 284         break;
 285     case TBitString: {
 286         Member *m;
 287         int pos = 0;
 288
 289         if (ASN1_TAILQ_EMPTY(t->members)) {
 290             decode_primitive ("bit_string", name, forwstr);
 291             break;
 292         }
 293         fprintf(codefile,
 294                 "if (len < 1) return ASN1_OVERRUN;\n"
 295                 "p++; len--; ret++;\n");
 296         fprintf(codefile,
 297                 "do {\n"
 298                 "if (len < 1) break;\n");
 299         ASN1_TAILQ_FOREACH(m, t->members, members) {
 300             while (m->val / 8 > pos / 8) {
 301                 fprintf (codefile,
 302                          "p++; len--; ret++;\n"
 303                          "if (len < 1) break;\n");
 304                 pos += 8;
 305             }
 306             fprintf (codefile,
 307                      "(%s)->%s = (*p >> %d) & 1;\n",
 308                      name, m->gen_name, 7 - m->val % 8);
 309         }
 310         fprintf(codefile,
 311                 "} while(0);\n");
 312         fprintf (codefile,
 313                  "p += len; ret += len;\n");
 314         break;
 315     }
 316     case TSequence: {
 317         Member *m;
 318
 319         if (t->members == NULL)
 320             break;
 321
 322         ASN1_TAILQ_FOREACH(m, t->members, members) {
 323             char *s = NULL;
 324
 325             if (m->ellipsis)
 326                 continue;
 327
 328             if (asprintf (&s, "%s(%s)->%s", m->optional ? "" : "&",
 329                           name, m->gen_name) < 0 || s == NULL)
 330                 errx(1, "malloc");
 331             decode_type (s, m->type, m->optional, forwstr, m->gen_name, NULL);
 332             free (s);
 333         }
 334
 335         break;
 336     }
 337     case TSet: {
 338         Member *m;
 339         unsigned int memno;
 340
 341         if(t->members == NULL)
 342             break;
 343
 344         fprintf(codefile, "{\n");
 345         fprintf(codefile, "unsigned int members = 0;\n");
 346         fprintf(codefile, "while(len > 0) {\n");
 347         fprintf(codefile,
 348                 "Der_class class;\n"
 349                 "Der_type type;\n"
 350                 "int tag;\n"
 351                 "e = der_get_tag (p, len, &class, &type, &tag, NULL);\n"
 352                 "if(e) %s;\n", forwstr);
 353         fprintf(codefile, "switch (MAKE_TAG(class, type, tag)) {\n");
 354         memno = 0;
 355         ASN1_TAILQ_FOREACH(m, t->members, members) {
 356             char *s;
 357
 358             assert(m->type->type == TTag);
 359
 360             fprintf(codefile, "case MAKE_TAG(%s, %s, %s):\n",
 361                     classname(m->type->tag.tagclass),
 362                     is_primitive_type(m->type->subtype->type) ? "PRIM" : "CONS",
 363                     valuename(m->type->tag.tagclass, m->type->tag.tagvalue));
 364
 365             if (asprintf (&s, "%s(%s)->%s", m->optional ? "" : "&", name, m->gen_name) < 0 || s == NULL)
 366                 errx(1, "malloc");
 367             if(m->optional)
 368                 fprintf(codefile,
 369                         "%s = calloc(1, sizeof(*%s));\n"
 370                         "if (%s == NULL) { e = ENOMEM; %s; }\n",
 371                         s, s, s, forwstr);
 372             decode_type (s, m->type, 0, forwstr, m->gen_name, NULL);
 373             free (s);
 374
 375             fprintf(codefile, "members |= (1 << %d);\n", memno);
 376             memno++;
 377             fprintf(codefile, "break;\n");
 378         }
 379         fprintf(codefile,
 380                 "default:\n"
 381                 "return ASN1_MISPLACED_FIELD;\n"
 382                 "break;\n");
 383         fprintf(codefile, "}\n");
 384         fprintf(codefile, "}\n");
 385         memno = 0;
 386         ASN1_TAILQ_FOREACH(m, t->members, members) {
 387             char *s;
 388
 389             if (asprintf (&s, "%s->%s", name, m->gen_name) < 0 || s == NULL)
 390                 errx(1, "malloc");
 391             fprintf(codefile, "if((members & (1 << %d)) == 0)\n", memno);
 392             if(m->optional)
 393                 fprintf(codefile, "%s = NULL;\n", s);
 394             else if(m->defval)
 395                 gen_assign_defval(s, m->defval);
 396             else
 397                 fprintf(codefile, "return ASN1_MISSING_FIELD;\n");
 398             free(s);
 399             memno++;
 400         }
 401         fprintf(codefile, "}\n");
 402         break;
 403     }
 404     case TSetOf:
 405     case TSequenceOf: {
 406         char *n = NULL;
 407         char *sname = NULL;
 408
 409         fprintf (codefile,
 410                  "{\n"
 411                  "size_t %s_origlen = len;\n"
 412                  "size_t %s_oldret = ret;\n"
 413                  "size_t %s_olen = 0;\n"
 414                  "void *%s_tmp;\n"
 415                  "ret = 0;\n"
 416                  "(%s)->len = 0;\n"
 417                  "(%s)->val = NULL;\n",
 418                  tmpstr,
 419                  tmpstr,
 420                  tmpstr,
 421                  tmpstr,
 422                  name,
 423                  name);
 424
 425         fprintf (codefile,
 426                  "while(ret < %s_origlen) {\n"
 427                  "size_t %s_nlen = %s_olen + sizeof(*((%s)->val));\n"
 428                  "if (%s_olen > %s_nlen) { e = ASN1_OVERFLOW; %s; }\n"
 429                  "%s_olen = %s_nlen;\n"
 430                  "%s_tmp = realloc((%s)->val, %s_olen);\n"
 431                  "if (%s_tmp == NULL) { e = ENOMEM; %s; }\n"
 432                  "(%s)->val = %s_tmp;\n",
 433                  tmpstr,
 434                  tmpstr, tmpstr, name,
 435                  tmpstr, tmpstr, forwstr,
 436                  tmpstr, tmpstr,
 437                  tmpstr, name, tmpstr,
 438                  tmpstr, forwstr,
 439                  name, tmpstr);
 440
 441         if (asprintf (&n, "&(%s)->val[(%s)->len]", name, name) < 0 || n == NULL)
 442             errx(1, "malloc");
 443         if (asprintf (&sname, "%s_s_of", tmpstr) < 0 || sname == NULL)
 444             errx(1, "malloc");
 445         decode_type (n, t->subtype, 0, forwstr, sname, NULL);
 446         fprintf (codefile,
 447                  "(%s)->len++;\n"
 448                  "len = %s_origlen - ret;\n"
 449                  "}\n"
 450                  "ret += %s_oldret;\n"
 451                  "}\n",
 452                  name,
 453                  tmpstr, tmpstr);
 454         if (t->range)
 455             range_check(name, "len", forwstr, t->range);
 456         free (n);
 457         free (sname);
 458         break;
 459     }
 460     case TGeneralizedTime:
 461         decode_primitive ("generalized_time", name, forwstr);
 462         break;
 463     case TGeneralString:
 464         decode_primitive ("general_string", name, forwstr);
 465         break;
 466     case TTeletexString:
 467         decode_primitive ("general_string", name, forwstr);
 468         break;
 469     case TTag:{
 470         char *tname = NULL, *typestring = NULL;
 471         char *ide = NULL;
 472
 473         if (asprintf(&typestring, "%s_type", tmpstr) < 0 || typestring == NULL)
 474             errx(1, "malloc");
 475
 476         fprintf(codefile,
 477                 "{\n"
 478                 "size_t %s_datalen, %s_oldlen;\n"
 479                 "Der_type %s;\n",
 480                 tmpstr, tmpstr, typestring);
 481         if(support_ber)
 482             fprintf(codefile,
 483                     "int is_indefinite;\n");
 484
 485         fprintf(codefile, "e = der_match_tag_and_length(p, len, %s, &%s, %s, "
 486                 "&%s_datalen, &l);\n",
 487                 classname(t->tag.tagclass),
 488                 typestring,
 489                 valuename(t->tag.tagclass, t->tag.tagvalue),
 490                 tmpstr);
 491
 492         /* XXX hardcode for now */
 493         if (support_ber && t->subtype->type == TOctetString) {
 494             ide = typestring;
 495         } else {
 496             fprintf(codefile,
 497                     "if (e == 0 && %s != %s) { e = ASN1_BAD_ID; }\n",
 498                     typestring,
 499                     is_primitive_type(t->subtype->type) ? "PRIM" : "CONS");
 500         }
 501
 502         if(optional) {
 503             fprintf(codefile,
 504                     "if(e) {\n"
 505                     "%s = NULL;\n"
 506                     "} else {\n"
 507                      "%s = calloc(1, sizeof(*%s));\n"
 508                      "if (%s == NULL) { e = ENOMEM; %s; }\n",
 509                      name, name, name, name, forwstr);
 510         } else {
 511             fprintf(codefile, "if(e) %s;\n", forwstr);
 512         }
 513         fprintf (codefile,
 514                  "p += l; len -= l; ret += l;\n"
 515                  "%s_oldlen = len;\n",
 516                  tmpstr);
 517         if(support_ber)
 518             fprintf (codefile,
 519                      "if((is_indefinite = _heim_fix_dce(%s_datalen, &len)) < 0)\n"
 520                      "{ e = ASN1_BAD_FORMAT; %s; }\n"
 521                      "if (is_indefinite) { if (len < 2) { e = ASN1_OVERRUN; %s; } len -= 2; }",
 522                      tmpstr, forwstr, forwstr);
 523         else
 524             fprintf(codefile,
 525                     "if (%s_datalen > len) { e = ASN1_OVERRUN; %s; }\n"
 526                     "len = %s_datalen;\n", tmpstr, forwstr, tmpstr);
 527         if (asprintf (&tname, "%s_Tag", tmpstr) < 0 || tname == NULL)
 528             errx(1, "malloc");
 529         decode_type (name, t->subtype, 0, forwstr, tname, ide);
 530         if(support_ber)
 531             fprintf(codefile,
 532                     "if(is_indefinite){\n"
 533                     "len += 2;\n"
 534                     "e = der_match_tag_and_length(p, len, "
 535                     "(Der_class)0, &%s, UT_EndOfContent, "
 536                     "&%s_datalen, &l);\n"
 537                     "if(e) %s;\n"
 538                     "p += l; len -= l; ret += l;\n"
 539                     "if (%s != (Der_type)0) { e = ASN1_BAD_ID; %s; }\n"
 540                     "} else \n",
 541                     typestring,
 542                     tmpstr,
 543                     forwstr,
 544                     typestring, forwstr);
 545         fprintf(codefile,
 546                 "len = %s_oldlen - %s_datalen;\n",
 547                 tmpstr, tmpstr);
 548         if(optional)
 549             fprintf(codefile,
 550                     "}\n");
 551         fprintf(codefile,
 552                 "}\n");
 553         free(tname);
 554         free(typestring);
 555         break;
 556     }
 557     case TChoice: {
 558         Member *m, *have_ellipsis = NULL;
 559         const char *els = "";
 560
 561         if (t->members == NULL)
 562             break;
 563
 564         ASN1_TAILQ_FOREACH(m, t->members, members) {
 565             const Type *tt = m->type;
 566             char *s = NULL;
 567             Der_class cl;
 568             Der_type  ty;
 569             unsigned  tag;
 570
 571             if (m->ellipsis) {
 572                 have_ellipsis = m;
 573                 continue;
 574             }
 575
 576             find_tag(tt, &cl, &ty, &tag);
 577
 578             fprintf(codefile,
 579                     "%sif (der_match_tag(p, len, %s, %s, %s, NULL) == 0) {\n",
 580                     els,
 581                     classname(cl),
 582                     ty ? "CONS" : "PRIM",
 583                     valuename(cl, tag));
 584             if (asprintf (&s, "%s(%s)->u.%s", m->optional ? "" : "&",
 585                           name, m->gen_name) < 0 || s == NULL)
 586                 errx(1, "malloc");
 587             decode_type (s, m->type, m->optional, forwstr, m->gen_name, NULL);
 588             fprintf(codefile,
 589                     "(%s)->element = %s;\n",
 590                     name, m->label);
 591             free(s);
 592             fprintf(codefile,
 593                     "}\n");
 594             els = "else ";
 595         }
 596         if (have_ellipsis) {
 597             fprintf(codefile,
 598                     "else {\n"
 599                     "(%s)->u.%s.data = calloc(1, len);\n"
 600                     "if ((%s)->u.%s.data == NULL) {\n"
 601                     "e = ENOMEM; %s;\n"
 602                     "}\n"
 603                     "(%s)->u.%s.length = len;\n"
 604                     "memcpy((%s)->u.%s.data, p, len);\n"
 605                     "(%s)->element = %s;\n"
 606                     "p += len;\n"
 607                     "ret += len;\n"
 608                     "len -= len;\n"
 609                     "}\n",
 610                     name, have_ellipsis->gen_name,
 611                     name, have_ellipsis->gen_name,
 612                     forwstr,
 613                     name, have_ellipsis->gen_name,
 614                     name, have_ellipsis->gen_name,
 615                     name, have_ellipsis->label);
 616         } else {
 617             fprintf(codefile,
 618                     "else {\n"
 619                     "e = ASN1_PARSE_ERROR;\n"
 620                     "%s;\n"
 621                     "}\n",
 622                     forwstr);
 623         }
 624         break;
 625     }
 626     case TUTCTime:
 627         decode_primitive ("utctime", name, forwstr);
 628         break;
 629     case TUTF8String:
 630         decode_primitive ("utf8string", name, forwstr);
 631         break;
 632     case TPrintableString:
 633         decode_primitive ("printable_string", name, forwstr);
 634         break;
 635     case TIA5String:
 636         decode_primitive ("ia5_string", name, forwstr);
 637         break;
 638     case TBMPString:
 639         decode_primitive ("bmp_string", name, forwstr);
 640         break;
 641     case TUniversalString:
 642         decode_primitive ("universal_string", name, forwstr);
 643         break;
 644     case TVisibleString:
 645         decode_primitive ("visible_string", name, forwstr);
 646         break;
 647     case TNull:
 648         fprintf (codefile, "/* NULL */\n");
 649         break;
 650     case TOID:
 651         decode_primitive ("oid", name, forwstr);
 652         break;
 653     default :
 654         abort ();
 655     }
 656     return 0;
 657 }
 658
 659 void
 660 generate_type_decode (const Symbol *s)
 661 {
 662     int preserve = preserve_type(s->name) ? TRUE : FALSE;
 663
 664     fprintf (codefile, "int ASN1CALL\n"
 665              "decode_%s(const unsigned char *p,"
 666              " size_t len, %s *data, size_t *size)\n"
 667              "{\n",
 668              s->gen_name, s->gen_name);
 669
 670     switch (s->type->type) {
 671     case TInteger:
 672     case TBoolean:
 673     case TOctetString:
 674     case TOID:
 675     case TGeneralizedTime:
 676     case TGeneralString:
 677     case TTeletexString:
 678     case TUTF8String:
 679     case TPrintableString:
 680     case TIA5String:
 681     case TBMPString:
 682     case TUniversalString:
 683     case TVisibleString:
 684     case TUTCTime:
 685     case TNull:
 686     case TEnumerated:
 687     case TBitString:
 688     case TSequence:
 689     case TSequenceOf:
 690     case TSet:
 691     case TSetOf:
 692     case TTag:
 693     case TType:
 694     case TChoice:
 695         fprintf (codefile,
 696                  "size_t ret = 0;\n"
 697                  "size_t l;\n"
 698                  "int e;\n");
 699         if (preserve)
 700             fprintf (codefile, "const unsigned char *begin = p;\n");
 701
 702         fprintf (codefile, "\n");
 703         fprintf (codefile, "memset(data, 0, sizeof(*data));\n"); /* hack to avoid `unused variable' */
 704
 705         decode_type ("data", s->type, 0, "goto fail", "Top", NULL);
 706         if (preserve)
 707             fprintf (codefile,
 708                      "data->_save.data = calloc(1, ret);\n"
 709                      "if (data->_save.data == NULL) { \n"
 710                      "e = ENOMEM; goto fail; \n"
 711                      "}\n"
 712                      "data->_save.length = ret;\n"
 713                      "memcpy(data->_save.data, begin, ret);\n");
 714         fprintf (codefile,
 715                  "if(size) *size = ret;\n"
 716                  "return 0;\n");
 717         fprintf (codefile,
 718                  "fail:\n"
 719                  "free_%s(data);\n"
 720                  "return e;\n",
 721                  s->gen_name);
 722         break;
 723     default:
 724         abort ();
 725     }
 726     fprintf (codefile, "}\n\n");
 727 }