xref: /freebsd/crypto/heimdal/lib/asn1/gen_decode.c (revision abd87254)
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 	    lex_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 > %" PRId64 ") {\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 < %" PRId64 ") {\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 != %" PRId64 ") {\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 	     unsigned int depth)
214 {
215     switch (t->type) {
216     case TType: {
217 	if (optional)
218 	    fprintf(codefile,
219 		    "%s = calloc(1, sizeof(*%s));\n"
220 		    "if (%s == NULL) %s;\n",
221 		    name, name, name, forwstr);
222 	fprintf (codefile,
223 		 "e = decode_%s(p, len, %s, &l);\n",
224 		 t->symbol->gen_name, name);
225 	if (optional) {
226 	    fprintf (codefile,
227 		     "if(e) {\n"
228 		     "free(%s);\n"
229 		     "%s = NULL;\n"
230 		     "} else {\n"
231 		     "p += l; len -= l; ret += l;\n"
232 		     "}\n",
233 		     name, name);
234 	} else {
235 	    fprintf (codefile,
236 		     "if(e) %s;\n",
237 		     forwstr);
238 	    fprintf (codefile,
239 		     "p += l; len -= l; ret += l;\n");
240 	}
241 	break;
242     }
243     case TInteger:
244 	if(t->members) {
245 	    fprintf(codefile,
246 		    "{\n"
247 		    "int enumint;\n");
248 	    decode_primitive ("integer", "&enumint", forwstr);
249 	    fprintf(codefile,
250 		    "*%s = enumint;\n"
251 		    "}\n",
252 		    name);
253 	} else if (t->range == NULL) {
254 	    decode_primitive ("heim_integer", name, forwstr);
255 	} else if (t->range->min < INT_MIN && t->range->max <= INT64_MAX) {
256 	    decode_primitive ("integer64", name, forwstr);
257 	} else if (t->range->min >= 0 && t->range->max > UINT_MAX) {
258 	    decode_primitive ("unsigned64", name, forwstr);
259 	} else if (t->range->min >= INT_MIN && t->range->max <= INT_MAX) {
260 	    decode_primitive ("integer", name, forwstr);
261 	} else if (t->range->min >= 0 && t->range->max <= UINT_MAX) {
262 	    decode_primitive ("unsigned", name, forwstr);
263 	} else
264 	    errx(1, "%s: unsupported range %" PRId64 " -> %" PRId64,
265 		 name, t->range->min, t->range->max);
266 	break;
267     case TBoolean:
268       decode_primitive ("boolean", name, forwstr);
269       break;
270     case TEnumerated:
271 	decode_primitive ("enumerated", name, forwstr);
272 	break;
273     case TOctetString:
274 	if (dertype) {
275 	    fprintf(codefile,
276 		    "if (%s == CONS) {\n",
277 		    dertype);
278 	    decode_primitive("octet_string_ber", name, forwstr);
279 	    fprintf(codefile,
280 		    "} else {\n");
281 	}
282 	decode_primitive ("octet_string", name, forwstr);
283 	if (dertype)
284 	    fprintf(codefile, "}\n");
285 	if (t->range)
286 	    range_check(name, "length", forwstr, t->range);
287 	break;
288     case TBitString: {
289 	Member *m;
290 	int pos = 0;
291 
292 	if (ASN1_TAILQ_EMPTY(t->members)) {
293 	    decode_primitive ("bit_string", name, forwstr);
294 	    break;
295 	}
296 	fprintf(codefile,
297 		"if (len < 1) return ASN1_OVERRUN;\n"
298 		"p++; len--; ret++;\n");
299 	fprintf(codefile,
300 		"do {\n"
301 		"if (len < 1) break;\n");
302 	ASN1_TAILQ_FOREACH(m, t->members, members) {
303 	    while (m->val / 8 > pos / 8) {
304 		fprintf (codefile,
305 			 "p++; len--; ret++;\n"
306 			 "if (len < 1) break;\n");
307 		pos += 8;
308 	    }
309 	    fprintf (codefile,
310 		     "(%s)->%s = (*p >> %d) & 1;\n",
311 		     name, m->gen_name, 7 - m->val % 8);
312 	}
313 	fprintf(codefile,
314 		"} while(0);\n");
315 	fprintf (codefile,
316 		 "p += len; ret += len;\n");
317 	break;
318     }
319     case TSequence: {
320 	Member *m;
321 
322 	if (t->members == NULL)
323 	    break;
324 
325 	ASN1_TAILQ_FOREACH(m, t->members, members) {
326 	    char *s = NULL;
327 
328 	    if (m->ellipsis)
329 		continue;
330 
331 	    if (asprintf (&s, "%s(%s)->%s", m->optional ? "" : "&",
332 			  name, m->gen_name) < 0 || s == NULL)
333 		errx(1, "malloc");
334 	    decode_type (s, m->type, m->optional, forwstr, m->gen_name, NULL,
335 		depth + 1);
336 	    free (s);
337 	}
338 
339 	break;
340     }
341     case TSet: {
342 	Member *m;
343 	unsigned int memno;
344 
345 	if(t->members == NULL)
346 	    break;
347 
348 	fprintf(codefile, "{\n");
349 	fprintf(codefile, "unsigned int members = 0;\n");
350 	fprintf(codefile, "while(len > 0) {\n");
351 	fprintf(codefile,
352 		"Der_class class;\n"
353 		"Der_type type;\n"
354 		"int tag;\n"
355 		"e = der_get_tag (p, len, &class, &type, &tag, NULL);\n"
356 		"if(e) %s;\n", forwstr);
357 	fprintf(codefile, "switch (MAKE_TAG(class, type, tag)) {\n");
358 	memno = 0;
359 	ASN1_TAILQ_FOREACH(m, t->members, members) {
360 	    char *s;
361 
362 	    assert(m->type->type == TTag);
363 
364 	    fprintf(codefile, "case MAKE_TAG(%s, %s, %s):\n",
365 		    classname(m->type->tag.tagclass),
366 		    is_primitive_type(m->type->subtype->type) ? "PRIM" : "CONS",
367 		    valuename(m->type->tag.tagclass, m->type->tag.tagvalue));
368 
369 	    if (asprintf (&s, "%s(%s)->%s", m->optional ? "" : "&", name, m->gen_name) < 0 || s == NULL)
370 		errx(1, "malloc");
371 	    if(m->optional)
372 		fprintf(codefile,
373 			"%s = calloc(1, sizeof(*%s));\n"
374 			"if (%s == NULL) { e = ENOMEM; %s; }\n",
375 			s, s, s, forwstr);
376 	    decode_type (s, m->type, 0, forwstr, m->gen_name, NULL, depth + 1);
377 	    free (s);
378 
379 	    fprintf(codefile, "members |= (1 << %d);\n", memno);
380 	    memno++;
381 	    fprintf(codefile, "break;\n");
382 	}
383 	fprintf(codefile,
384 		"default:\n"
385 		"return ASN1_MISPLACED_FIELD;\n"
386 		"break;\n");
387 	fprintf(codefile, "}\n");
388 	fprintf(codefile, "}\n");
389 	memno = 0;
390 	ASN1_TAILQ_FOREACH(m, t->members, members) {
391 	    char *s;
392 
393 	    if (asprintf (&s, "%s->%s", name, m->gen_name) < 0 || s == NULL)
394 		errx(1, "malloc");
395 	    fprintf(codefile, "if((members & (1 << %d)) == 0)\n", memno);
396 	    if(m->optional)
397 		fprintf(codefile, "%s = NULL;\n", s);
398 	    else if(m->defval)
399 		gen_assign_defval(s, m->defval);
400 	    else
401 		fprintf(codefile, "return ASN1_MISSING_FIELD;\n");
402 	    free(s);
403 	    memno++;
404 	}
405 	fprintf(codefile, "}\n");
406 	break;
407     }
408     case TSetOf:
409     case TSequenceOf: {
410 	char *n = NULL;
411 	char *sname = NULL;
412 
413 	fprintf (codefile,
414 		 "{\n"
415 		 "size_t %s_origlen = len;\n"
416 		 "size_t %s_oldret = ret;\n"
417 		 "size_t %s_olen = 0;\n"
418 		 "void *%s_tmp;\n"
419 		 "ret = 0;\n"
420 		 "(%s)->len = 0;\n"
421 		 "(%s)->val = NULL;\n",
422 		 tmpstr,
423 		 tmpstr,
424 		 tmpstr,
425 		 tmpstr,
426 		 name,
427 		 name);
428 
429 	fprintf (codefile,
430 		 "while(ret < %s_origlen) {\n"
431 		 "size_t %s_nlen = %s_olen + sizeof(*((%s)->val));\n"
432 		 "if (%s_olen > %s_nlen) { e = ASN1_OVERFLOW; %s; }\n"
433 		 "%s_olen = %s_nlen;\n"
434 		 "%s_tmp = realloc((%s)->val, %s_olen);\n"
435 		 "if (%s_tmp == NULL) { e = ENOMEM; %s; }\n"
436 		 "(%s)->val = %s_tmp;\n",
437 		 tmpstr,
438 		 tmpstr, tmpstr, name,
439 		 tmpstr, tmpstr, forwstr,
440 		 tmpstr, tmpstr,
441 		 tmpstr, name, tmpstr,
442 		 tmpstr, forwstr,
443 		 name, tmpstr);
444 
445 	if (asprintf (&n, "&(%s)->val[(%s)->len]", name, name) < 0 || n == NULL)
446 	    errx(1, "malloc");
447 	if (asprintf (&sname, "%s_s_of", tmpstr) < 0 || sname == NULL)
448 	    errx(1, "malloc");
449 	decode_type (n, t->subtype, 0, forwstr, sname, NULL, depth + 1);
450 	fprintf (codefile,
451 		 "(%s)->len++;\n"
452 		 "len = %s_origlen - ret;\n"
453 		 "}\n"
454 		 "ret += %s_oldret;\n"
455 		 "}\n",
456 		 name,
457 		 tmpstr, tmpstr);
458 	if (t->range)
459 	    range_check(name, "len", forwstr, t->range);
460 	free (n);
461 	free (sname);
462 	break;
463     }
464     case TGeneralizedTime:
465 	decode_primitive ("generalized_time", name, forwstr);
466 	break;
467     case TGeneralString:
468 	decode_primitive ("general_string", name, forwstr);
469 	break;
470     case TTeletexString:
471 	decode_primitive ("general_string", name, forwstr);
472 	break;
473     case TTag:{
474     	char *tname = NULL, *typestring = NULL;
475 	char *ide = NULL;
476 
477 	if (asprintf(&typestring, "%s_type", tmpstr) < 0 || typestring == NULL)
478 	    errx(1, "malloc");
479 
480 	fprintf(codefile,
481 		"{\n"
482 		"size_t %s_datalen, %s_oldlen;\n"
483 		"Der_type %s;\n",
484 		tmpstr, tmpstr, typestring);
485 	if(support_ber)
486 	    fprintf(codefile,
487 		    "int is_indefinite%u;\n", depth);
488 
489 	fprintf(codefile, "e = der_match_tag_and_length(p, len, %s, &%s, %s, "
490 		"&%s_datalen, &l);\n",
491 		classname(t->tag.tagclass),
492 		typestring,
493 		valuename(t->tag.tagclass, t->tag.tagvalue),
494 		tmpstr);
495 
496 	/* XXX hardcode for now */
497 	if (support_ber && t->subtype->type == TOctetString) {
498 	    ide = typestring;
499 	} else {
500 	    fprintf(codefile,
501 		    "if (e == 0 && %s != %s) { e = ASN1_BAD_ID; }\n",
502 		    typestring,
503 		    is_primitive_type(t->subtype->type) ? "PRIM" : "CONS");
504 	}
505 
506 	if(optional) {
507 	    fprintf(codefile,
508 		    "if(e) {\n"
509 		    "%s = NULL;\n"
510 		    "} else {\n"
511 		     "%s = calloc(1, sizeof(*%s));\n"
512 		     "if (%s == NULL) { e = ENOMEM; %s; }\n",
513 		     name, name, name, name, forwstr);
514 	} else {
515 	    fprintf(codefile, "if(e) %s;\n", forwstr);
516 	}
517 	fprintf (codefile,
518 		 "p += l; len -= l; ret += l;\n"
519 		 "%s_oldlen = len;\n",
520 		 tmpstr);
521 	if(support_ber)
522 	    fprintf (codefile,
523 		     "if((is_indefinite%u = _heim_fix_dce(%s_datalen, &len)) < 0)\n"
524 		     "{ e = ASN1_BAD_FORMAT; %s; }\n"
525 		     "if (is_indefinite%u) { if (len < 2) { e = ASN1_OVERRUN; %s; } len -= 2; }",
526 		     depth, tmpstr, forwstr, depth, forwstr);
527 	else
528 	    fprintf(codefile,
529 		    "if (%s_datalen > len) { e = ASN1_OVERRUN; %s; }\n"
530 		    "len = %s_datalen;\n", tmpstr, forwstr, tmpstr);
531 	if (asprintf (&tname, "%s_Tag", tmpstr) < 0 || tname == NULL)
532 	    errx(1, "malloc");
533 	decode_type (name, t->subtype, 0, forwstr, tname, ide, depth + 1);
534 	if(support_ber)
535 	    fprintf(codefile,
536 		    "if(is_indefinite%u){\n"
537 		    "len += 2;\n"
538 		    "e = der_match_tag_and_length(p, len, "
539 		    "(Der_class)0, &%s, UT_EndOfContent, "
540 		    "&%s_datalen, &l);\n"
541 		    "if(e) %s;\n"
542 		    "p += l; len -= l; ret += l;\n"
543 		    "if (%s != (Der_type)0) { e = ASN1_BAD_ID; %s; }\n"
544 		    "} else \n",
545 		    depth,
546 		    typestring,
547 		    tmpstr,
548 		    forwstr,
549 		    typestring, forwstr);
550 	fprintf(codefile,
551 		"len = %s_oldlen - %s_datalen;\n",
552 		tmpstr, tmpstr);
553 	if(optional)
554 	    fprintf(codefile,
555 		    "}\n");
556 	fprintf(codefile,
557 		"}\n");
558 	free(tname);
559 	free(typestring);
560 	break;
561     }
562     case TChoice: {
563 	Member *m, *have_ellipsis = NULL;
564 	const char *els = "";
565 
566 	if (t->members == NULL)
567 	    break;
568 
569 	ASN1_TAILQ_FOREACH(m, t->members, members) {
570 	    const Type *tt = m->type;
571 	    char *s = NULL;
572 	    Der_class cl;
573 	    Der_type  ty;
574 	    unsigned  tag;
575 
576 	    if (m->ellipsis) {
577 		have_ellipsis = m;
578 		continue;
579 	    }
580 
581 	    find_tag(tt, &cl, &ty, &tag);
582 
583 	    fprintf(codefile,
584 		    "%sif (der_match_tag(p, len, %s, %s, %s, NULL) == 0) {\n",
585 		    els,
586 		    classname(cl),
587 		    ty ? "CONS" : "PRIM",
588 		    valuename(cl, tag));
589 	    fprintf(codefile,
590 		    "(%s)->element = %s;\n",
591 		    name, m->label);
592 	    if (asprintf (&s, "%s(%s)->u.%s", m->optional ? "" : "&",
593 			  name, m->gen_name) < 0 || s == NULL)
594 		errx(1, "malloc");
595 	    decode_type (s, m->type, m->optional, forwstr, m->gen_name, NULL,
596 		depth + 1);
597 	    free(s);
598 	    fprintf(codefile,
599 		    "}\n");
600 	    els = "else ";
601 	}
602 	if (have_ellipsis) {
603 	    fprintf(codefile,
604 		    "else {\n"
605 		    "(%s)->element = %s;\n"
606 		    "(%s)->u.%s.data = calloc(1, len);\n"
607 		    "if ((%s)->u.%s.data == NULL) {\n"
608 		    "e = ENOMEM; %s;\n"
609 		    "}\n"
610 		    "(%s)->u.%s.length = len;\n"
611 		    "memcpy((%s)->u.%s.data, p, len);\n"
612 		    "p += len;\n"
613 		    "ret += len;\n"
614 		    "len = 0;\n"
615 		    "}\n",
616 		    name, have_ellipsis->label,
617 		    name, have_ellipsis->gen_name,
618 		    name, have_ellipsis->gen_name,
619 		    forwstr,
620 		    name, have_ellipsis->gen_name,
621 		    name, have_ellipsis->gen_name);
622 	} else {
623 	    fprintf(codefile,
624 		    "else {\n"
625 		    "e = ASN1_PARSE_ERROR;\n"
626 		    "%s;\n"
627 		    "}\n",
628 		    forwstr);
629 	}
630 	break;
631     }
632     case TUTCTime:
633 	decode_primitive ("utctime", name, forwstr);
634 	break;
635     case TUTF8String:
636 	decode_primitive ("utf8string", name, forwstr);
637 	break;
638     case TPrintableString:
639 	decode_primitive ("printable_string", name, forwstr);
640 	break;
641     case TIA5String:
642 	decode_primitive ("ia5_string", name, forwstr);
643 	break;
644     case TBMPString:
645 	decode_primitive ("bmp_string", name, forwstr);
646 	break;
647     case TUniversalString:
648 	decode_primitive ("universal_string", name, forwstr);
649 	break;
650     case TVisibleString:
651 	decode_primitive ("visible_string", name, forwstr);
652 	break;
653     case TNull:
654 	fprintf (codefile, "/* NULL */\n");
655 	break;
656     case TOID:
657 	decode_primitive ("oid", name, forwstr);
658 	break;
659     default :
660 	abort ();
661     }
662     return 0;
663 }
664 
665 void
666 generate_type_decode (const Symbol *s)
667 {
668     int preserve = preserve_type(s->name) ? TRUE : FALSE;
669 
670     fprintf (codefile, "int ASN1CALL\n"
671 	     "decode_%s(const unsigned char *p HEIMDAL_UNUSED_ATTRIBUTE,"
672 	     " size_t len HEIMDAL_UNUSED_ATTRIBUTE, %s *data, size_t *size)\n"
673 	     "{\n",
674 	     s->gen_name, s->gen_name);
675 
676     switch (s->type->type) {
677     case TInteger:
678     case TBoolean:
679     case TOctetString:
680     case TOID:
681     case TGeneralizedTime:
682     case TGeneralString:
683     case TTeletexString:
684     case TUTF8String:
685     case TPrintableString:
686     case TIA5String:
687     case TBMPString:
688     case TUniversalString:
689     case TVisibleString:
690     case TUTCTime:
691     case TNull:
692     case TEnumerated:
693     case TBitString:
694     case TSequence:
695     case TSequenceOf:
696     case TSet:
697     case TSetOf:
698     case TTag:
699     case TType:
700     case TChoice:
701 	fprintf (codefile,
702 		 "size_t ret = 0;\n"
703 		 "size_t l HEIMDAL_UNUSED_ATTRIBUTE;\n"
704 		 "int e HEIMDAL_UNUSED_ATTRIBUTE;\n");
705 	if (preserve)
706 	    fprintf (codefile, "const unsigned char *begin = p;\n");
707 
708 	fprintf (codefile, "\n");
709 	fprintf (codefile, "memset(data, 0, sizeof(*data));\n"); /* hack to avoid `unused variable' */
710 
711 	decode_type ("data", s->type, 0, "goto fail", "Top", NULL, 1);
712 	if (preserve)
713 	    fprintf (codefile,
714 		     "data->_save.data = calloc(1, ret);\n"
715 		     "if (data->_save.data == NULL) { \n"
716 		     "e = ENOMEM; goto fail; \n"
717 		     "}\n"
718 		     "data->_save.length = ret;\n"
719 		     "memcpy(data->_save.data, begin, ret);\n");
720 	fprintf (codefile,
721 		 "if(size) *size = ret;\n"
722 		 "return 0;\n");
723 	fprintf (codefile,
724 		 "fail:\n"
725 		 "free_%s(data);\n"
726 		 "return e;\n",
727 		 s->gen_name);
728 	break;
729     default:
730 	abort ();
731     }
732     fprintf (codefile, "}\n\n");
733 }
734