tasn_dec.c 27.7 KB
Newer Older
D
 
Dr. Stephen Henson 已提交
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60
/* tasn_dec.c */
/* Written by Dr Stephen N Henson (shenson@bigfoot.com) for the OpenSSL
 * project 2000.
 */
/* ====================================================================
 * Copyright (c) 2000 The OpenSSL Project.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer. 
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *
 * 3. All advertising materials mentioning features or use of this
 *    software must display the following acknowledgment:
 *    "This product includes software developed by the OpenSSL Project
 *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
 *
 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
 *    endorse or promote products derived from this software without
 *    prior written permission. For written permission, please contact
 *    licensing@OpenSSL.org.
 *
 * 5. Products derived from this software may not be called "OpenSSL"
 *    nor may "OpenSSL" appear in their names without prior written
 *    permission of the OpenSSL Project.
 *
 * 6. Redistributions of any form whatsoever must retain the following
 *    acknowledgment:
 *    "This product includes software developed by the OpenSSL Project
 *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
 *
 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
 * OF THE POSSIBILITY OF SUCH DAMAGE.
 * ====================================================================
 *
 * This product includes cryptographic software written by Eric Young
 * (eay@cryptsoft.com).  This product includes software written by Tim
 * Hudson (tjh@cryptsoft.com).
 *
 */


#include <stddef.h>
61
#include <string.h>
D
 
Dr. Stephen Henson 已提交
62 63 64 65 66 67
#include <openssl/asn1.h>
#include <openssl/asn1t.h>
#include <openssl/objects.h>
#include <openssl/buffer.h>
#include <openssl/err.h>

68 69 70
static int asn1_check_eoc(const unsigned char **in, long len);
static int asn1_collect(BUF_MEM *buf, const unsigned char **in, long len, char inf, int tag, int aclass);
static int collect_data(BUF_MEM *buf, const unsigned char **p, long plen);
D
 
Dr. Stephen Henson 已提交
71
static int asn1_check_tlen(long *olen, int *otag, unsigned char *oclass, char *inf, char *cst,
72 73 74 75
			const unsigned char **in, long len, int exptag, int expclass, char opt, ASN1_TLC *ctx);
static int asn1_template_ex_d2i(ASN1_VALUE **pval, const unsigned char **in, long len, const ASN1_TEMPLATE *tt, char opt, ASN1_TLC *ctx);
static int asn1_template_noexp_d2i(ASN1_VALUE **val, const unsigned char **in, long len, const ASN1_TEMPLATE *tt, char opt, ASN1_TLC *ctx);
static int asn1_d2i_ex_primitive(ASN1_VALUE **pval, const unsigned char **in, long len,
D
 
Dr. Stephen Henson 已提交
76 77
					const ASN1_ITEM *it, int tag, int aclass, char opt, ASN1_TLC *ctx);

D
 
Dr. Stephen Henson 已提交
78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96
/* Table to convert tags to bit values, used for MSTRING type */
static unsigned long tag2bit[32]={
0,	0,	0,	B_ASN1_BIT_STRING,	/* tags  0 -  3 */
B_ASN1_OCTET_STRING,	0,	0,		B_ASN1_UNKNOWN,/* tags  4- 7 */
B_ASN1_UNKNOWN,	B_ASN1_UNKNOWN,	B_ASN1_UNKNOWN,	B_ASN1_UNKNOWN,/* tags  8-11 */
B_ASN1_UTF8STRING,B_ASN1_UNKNOWN,B_ASN1_UNKNOWN,B_ASN1_UNKNOWN,/* tags 12-15 */
0,	0,	B_ASN1_NUMERICSTRING,B_ASN1_PRINTABLESTRING,   /* tags 16-19 */
B_ASN1_T61STRING,B_ASN1_VIDEOTEXSTRING,B_ASN1_IA5STRING,       /* tags 20-22 */
B_ASN1_UTCTIME, B_ASN1_GENERALIZEDTIME,			       /* tags 23-24 */	
B_ASN1_GRAPHICSTRING,B_ASN1_ISO64STRING,B_ASN1_GENERALSTRING,  /* tags 25-27 */
B_ASN1_UNIVERSALSTRING,B_ASN1_UNKNOWN,B_ASN1_BMPSTRING,B_ASN1_UNKNOWN, /* tags 28-31 */
	};

unsigned long ASN1_tag2bit(int tag)
{
	if((tag < 0) || (tag > 30)) return 0;
	return tag2bit[tag];
}

D
 
Dr. Stephen Henson 已提交
97 98 99 100 101 102 103 104 105 106 107 108
/* Macro to initialize and invalidate the cache */

#define asn1_tlc_clear(c)	if(c) (c)->valid = 0

/* Decode an ASN1 item, this currently behaves just 
 * like a standard 'd2i' function. 'in' points to 
 * a buffer to read the data from, in future we will
 * have more advanced versions that can input data
 * a piece at a time and this will simply be a special
 * case.
 */

109
ASN1_VALUE *ASN1_item_d2i(ASN1_VALUE **pval, const unsigned char **in, long len, const ASN1_ITEM *it)
D
 
Dr. Stephen Henson 已提交
110 111 112 113 114 115 116 117 118 119
{
	ASN1_TLC c;
	ASN1_VALUE *ptmpval = NULL;
	if(!pval) pval = &ptmpval;
	asn1_tlc_clear(&c);
	if(ASN1_item_ex_d2i(pval, in, len, it, -1, 0, 0, &c) > 0) 
		return *pval;
	return NULL;
}

120
int ASN1_template_d2i(ASN1_VALUE **pval, const unsigned char **in, long len, const ASN1_TEMPLATE *tt)
D
 
Dr. Stephen Henson 已提交
121 122 123 124 125 126 127 128 129 130 131
{
	ASN1_TLC c;
	asn1_tlc_clear(&c);
	return asn1_template_ex_d2i(pval, in, len, tt, 0, &c);
}


/* Decode an item, taking care of IMPLICIT tagging, if any.
 * If 'opt' set and tag mismatch return -1 to handle OPTIONAL
 */

132
int ASN1_item_ex_d2i(ASN1_VALUE **pval, const unsigned char **in, long len, const ASN1_ITEM *it,
D
 
Dr. Stephen Henson 已提交
133 134 135 136 137 138 139
				int tag, int aclass, char opt, ASN1_TLC *ctx)
{
	const ASN1_TEMPLATE *tt, *errtt = NULL;
	const ASN1_COMPAT_FUNCS *cf;
	const ASN1_EXTERN_FUNCS *ef;
	const ASN1_AUX *aux = it->funcs;
	ASN1_aux_cb *asn1_cb;
140 141 142
	const unsigned char *p, *q;
	unsigned char *wp=NULL;	/* BIG FAT WARNING!  BREAKS CONST WHERE USED */
	unsigned char imphack = 0, oclass;
D
 
Dr. Stephen Henson 已提交
143 144 145 146 147 148 149 150 151 152 153 154 155
	char seq_eoc, seq_nolen, cst, isopt;
	long tmplen;
	int i;
	int otag;
	int ret = 0;
	ASN1_VALUE *pchval, **pchptr, *ptmpval;
	if(!pval) return 0;
	if(aux && aux->asn1_cb) asn1_cb = aux->asn1_cb;
	else asn1_cb = 0;

	switch(it->itype) {

		case ASN1_ITYPE_PRIMITIVE:
156 157 158 159 160 161 162 163 164 165
		if(it->templates) {
			/* tagging or OPTIONAL is currently illegal on an item template
			 * because the flags can't get passed down. In practice this isn't
			 * a problem: we include the relevant flags from the item template
			 * in the template itself.
			 */
			if ((tag != -1) || opt) {
				ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_ILLEGAL_OPTIONS_ON_ITEM_TEMPLATE);
				goto err;
			}
D
 
Dr. Stephen Henson 已提交
166
			return asn1_template_ex_d2i(pval, in, len, it->templates, opt, ctx);
167
		}
D
 
Dr. Stephen Henson 已提交
168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233
		return asn1_d2i_ex_primitive(pval, in, len, it, tag, aclass, opt, ctx);
		break;

		case ASN1_ITYPE_MSTRING:
		p = *in;
		/* Just read in tag and class */
		ret = asn1_check_tlen(NULL, &otag, &oclass, NULL, NULL, &p, len, -1, 0, 1, ctx);
		if(!ret) {
			ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ERR_R_NESTED_ASN1_ERROR);
			goto err;
		} 
		/* Must be UNIVERSAL class */
		if(oclass != V_ASN1_UNIVERSAL) {
			/* If OPTIONAL, assume this is OK */
			if(opt) return -1;
			ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_MSTRING_NOT_UNIVERSAL);
			goto err;
		} 
		/* Check tag matches bit map */
		if(!(ASN1_tag2bit(otag) & it->utype)) {
			/* If OPTIONAL, assume this is OK */
			if(opt) return -1;
			ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_MSTRING_WRONG_TAG);
			goto err;
		} 
		return asn1_d2i_ex_primitive(pval, in, len, it, otag, 0, 0, ctx);

		case ASN1_ITYPE_EXTERN:
		/* Use new style d2i */
		ef = it->funcs;
		return ef->asn1_ex_d2i(pval, in, len, it, tag, aclass, opt, ctx);

		case ASN1_ITYPE_COMPAT:
		/* we must resort to old style evil hackery */
		cf = it->funcs;

		/* If OPTIONAL see if it is there */
		if(opt) {
			int exptag;
			p = *in;
			if(tag == -1) exptag = it->utype;
			else exptag = tag;
			/* Don't care about anything other than presence of expected tag */
			ret = asn1_check_tlen(NULL, NULL, NULL, NULL, NULL, &p, len, exptag, aclass, 1, ctx);
			if(!ret) {
				ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ERR_R_NESTED_ASN1_ERROR);
				goto err;
			}
			if(ret == -1) return -1;
		}
		/* This is the old style evil hack IMPLICIT handling:
		 * since the underlying code is expecting a tag and
		 * class other than the one present we change the
		 * buffer temporarily then change it back afterwards.
		 * This doesn't and never did work for tags > 30.
		 *
		 * Yes this is *horrible* but it is only needed for
		 * old style d2i which will hopefully not be around
		 * for much longer.
		 * FIXME: should copy the buffer then modify it so
		 * the input buffer can be const: we should *always*
		 * copy because the old style d2i might modify the
		 * buffer.
		 */

		if(tag != -1) {
234 235 236
			wp = *(unsigned char **)in;
			imphack = *wp;
			*wp = (unsigned char)((*p & V_ASN1_CONSTRUCTED) | it->utype);
D
 
Dr. Stephen Henson 已提交
237 238 239 240
		}

		ptmpval = cf->asn1_d2i(pval, in, len);

241
		if(tag != -1) *wp = imphack;
D
 
Dr. Stephen Henson 已提交
242 243 244 245 246 247 248 249 250

		if(ptmpval) return 1;
		ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ERR_R_NESTED_ASN1_ERROR);
		goto err;


		case ASN1_ITYPE_CHOICE:
		if(asn1_cb && !asn1_cb(ASN1_OP_D2I_PRE, pval, it))
				goto auxerr;
251 252 253 254 255 256 257 258

		/* Allocate structure */
		if(!*pval) {
			if(!ASN1_item_ex_new(pval, it)) {
				ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ERR_R_NESTED_ASN1_ERROR);
				goto err;
			}
		}
D
 
Dr. Stephen Henson 已提交
259 260 261 262
		/* CHOICE type, try each possibility in turn */
		pchval = NULL;
		p = *in;
		for(i = 0, tt=it->templates; i < it->tcount; i++, tt++) {
263
			pchptr = asn1_get_field_ptr(pval, tt);
D
 
Dr. Stephen Henson 已提交
264 265 266
			/* We mark field as OPTIONAL so its absence
			 * can be recognised.
			 */
267
			ret = asn1_template_ex_d2i(pchptr, &p, len, tt, 1, ctx);
D
 
Dr. Stephen Henson 已提交
268 269 270 271 272 273 274
			/* If field not present, try the next one */
			if(ret == -1) continue;
			/* If positive return, read OK, break loop */
			if(ret > 0) break;
			/* Otherwise must be an ASN1 parsing error */
			errtt = tt;
			ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ERR_R_NESTED_ASN1_ERROR);
275
			goto err;
D
 
Dr. Stephen Henson 已提交
276 277 278 279
		}
		/* Did we fall off the end without reading anything? */
		if(i == it->tcount) {
			/* If OPTIONAL, this is OK */
280 281 282 283 284
			if(opt) {
				/* Free and zero it */
				ASN1_item_ex_free(pval, it);
				return -1;
			}
D
 
Dr. Stephen Henson 已提交
285
			ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_NO_MATCHING_CHOICE_TYPE);
286
			goto err;
D
 
Dr. Stephen Henson 已提交
287 288 289 290 291 292 293
		}
		asn1_set_choice_selector(pval, i, it);
		*in = p;
		if(asn1_cb && !asn1_cb(ASN1_OP_D2I_POST, pval, it))
				goto auxerr;
		return 1;

294
		case ASN1_ITYPE_NDEF_SEQUENCE:
D
 
Dr. Stephen Henson 已提交
295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353
		case ASN1_ITYPE_SEQUENCE:
		p = *in;
		tmplen = len;

		/* If no IMPLICIT tagging set to SEQUENCE, UNIVERSAL */
		if(tag == -1) {
			tag = V_ASN1_SEQUENCE;
			aclass = V_ASN1_UNIVERSAL;
		}
		/* Get SEQUENCE length and update len, p */
		ret = asn1_check_tlen(&len, NULL, NULL, &seq_eoc, &cst, &p, len, tag, aclass, opt, ctx);
		if(!ret) {
			ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ERR_R_NESTED_ASN1_ERROR);
			goto err;
		} else if(ret == -1) return -1;
		if(aux && (aux->flags & ASN1_AFLG_BROKEN)) {
			len = tmplen - (p - *in);
			seq_nolen = 1;
		} else seq_nolen = seq_eoc;	/* If indefinite we don't do a length check */
		if(!cst) {
			ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_SEQUENCE_NOT_CONSTRUCTED);
			goto err;
		}

		if(!*pval) {
			if(!ASN1_item_ex_new(pval, it)) {
				ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ERR_R_NESTED_ASN1_ERROR);
				goto err;
			}
		}
		if(asn1_cb && !asn1_cb(ASN1_OP_D2I_PRE, pval, it))
				goto auxerr;

		/* Get each field entry */
		for(i = 0, tt = it->templates; i < it->tcount; i++, tt++) {
			const ASN1_TEMPLATE *seqtt;
			ASN1_VALUE **pseqval;
			seqtt = asn1_do_adb(pval, tt, 1);
			if(!seqtt) goto err;
			pseqval = asn1_get_field_ptr(pval, seqtt);
			/* Have we ran out of data? */
			if(!len) break;
			q = p;
			if(asn1_check_eoc(&p, len)) {
				if(!seq_eoc) {
					ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_UNEXPECTED_EOC);
					goto err;
				}
				len -= p - q;
				seq_eoc = 0;
				q = p;
				break;
			}
			/* This determines the OPTIONAL flag value. The field cannot
			 * be omitted if it is the last of a SEQUENCE and there is
			 * still data to be read. This isn't strictly necessary but
			 * it increases efficiency in some cases.
			 */
			if(i == (it->tcount - 1)) isopt = 0;
354
			else isopt = (char)(seqtt->flags & ASN1_TFLG_OPTIONAL);
D
 
Dr. Stephen Henson 已提交
355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420
			/* attempt to read in field, allowing each to be OPTIONAL */
			ret = asn1_template_ex_d2i(pseqval, &p, len, seqtt, isopt, ctx);
			if(!ret) {
				errtt = seqtt;
				goto err;
			} else if(ret == -1) {
				/* OPTIONAL component absent. Free and zero the field
				 */
				ASN1_template_free(pseqval, seqtt);
				continue;
			}
			/* Update length */
			len -= p - q;
		}
		/* Check for EOC if expecting one */
		if(seq_eoc && !asn1_check_eoc(&p, len)) {
			ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_MISSING_EOC);
			goto err;
		}
		/* Check all data read */
		if(!seq_nolen && len) {
			ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_SEQUENCE_LENGTH_MISMATCH);
			goto err;
		}

		/* If we get here we've got no more data in the SEQUENCE,
		 * however we may not have read all fields so check all
		 * remaining are OPTIONAL and clear any that are.
		 */
		for(; i < it->tcount; tt++, i++) {
			const ASN1_TEMPLATE *seqtt;
			seqtt = asn1_do_adb(pval, tt, 1);
			if(!seqtt) goto err;
			if(seqtt->flags & ASN1_TFLG_OPTIONAL) {
				ASN1_VALUE **pseqval;
				pseqval = asn1_get_field_ptr(pval, seqtt);
				ASN1_template_free(pseqval, seqtt);
			} else {
				errtt = seqtt;
				ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_FIELD_MISSING);
				goto err;
			}
		}
		/* Save encoding */
		if(!asn1_enc_save(pval, *in, p - *in, it)) goto auxerr;
		*in = p;
		if(asn1_cb && !asn1_cb(ASN1_OP_D2I_POST, pval, it))
				goto auxerr;
		return 1;

		default:
		return 0;
	}
	auxerr:
	ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_AUX_ERROR);
	err:
	ASN1_item_ex_free(pval, it);
	if(errtt) ERR_add_error_data(4, "Field=", errtt->field_name, ", Type=", it->sname);
	else ERR_add_error_data(2, "Type=", it->sname);
	return 0;
}

/* Templates are handled with two separate functions. One handles any EXPLICIT tag and the other handles the
 * rest.
 */

421
static int asn1_template_ex_d2i(ASN1_VALUE **val, const unsigned char **in, long inlen, const ASN1_TEMPLATE *tt, char opt, ASN1_TLC *ctx)
D
 
Dr. Stephen Henson 已提交
422 423 424 425
{
	int flags, aclass;
	int ret;
	long len;
426
	const unsigned char *p, *q;
D
 
Dr. Stephen Henson 已提交
427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482
	char exp_eoc;
	if(!val) return 0;
	flags = tt->flags;
	aclass = flags & ASN1_TFLG_TAG_CLASS;

	p = *in;

	/* Check if EXPLICIT tag expected */
	if(flags & ASN1_TFLG_EXPTAG) {
		char cst;
		/* Need to work out amount of data available to the inner content and where it
		 * starts: so read in EXPLICIT header to get the info.
		 */
		ret = asn1_check_tlen(&len, NULL, NULL, &exp_eoc, &cst, &p, inlen, tt->tag, aclass, opt, ctx);
		q = p;
		if(!ret) {
			ASN1err(ASN1_F_ASN1_TEMPLATE_EX_D2I, ERR_R_NESTED_ASN1_ERROR);
			return 0;
		} else if(ret == -1) return -1;
		if(!cst) {
			ASN1err(ASN1_F_ASN1_TEMPLATE_EX_D2I, ASN1_R_EXPLICIT_TAG_NOT_CONSTRUCTED);
			return 0;
		}
		/* We've found the field so it can't be OPTIONAL now */
		ret = asn1_template_noexp_d2i(val, &p, len, tt, 0, ctx);
		if(!ret) {
			ASN1err(ASN1_F_ASN1_TEMPLATE_EX_D2I, ERR_R_NESTED_ASN1_ERROR);
			return 0;
		}
		/* We read the field in OK so update length */
		len -= p - q;
		if(exp_eoc) {
			/* If NDEF we must have an EOC here */
			if(!asn1_check_eoc(&p, len)) {
				ASN1err(ASN1_F_ASN1_TEMPLATE_D2I, ASN1_R_MISSING_EOC);
				goto err;
			}
		} else {
			/* Otherwise we must hit the EXPLICIT tag end or its an error */
			if(len) {
				ASN1err(ASN1_F_ASN1_TEMPLATE_D2I, ASN1_R_EXPLICIT_LENGTH_MISMATCH);
				goto err;
			}
		}
	} else 
		return asn1_template_noexp_d2i(val, in, inlen, tt, opt, ctx);

	*in = p;
	return 1;

	err:
	ASN1_template_free(val, tt);
	*val = NULL;
	return 0;
}

483
static int asn1_template_noexp_d2i(ASN1_VALUE **val, const unsigned char **in, long len, const ASN1_TEMPLATE *tt, char opt, ASN1_TLC *ctx)
D
 
Dr. Stephen Henson 已提交
484 485 486
{
	int flags, aclass;
	int ret;
487
	const unsigned char *p, *q;
D
 
Dr. Stephen Henson 已提交
488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520
	if(!val) return 0;
	flags = tt->flags;
	aclass = flags & ASN1_TFLG_TAG_CLASS;

	p = *in;
	q = p;

	if(flags & ASN1_TFLG_SK_MASK) {
		/* SET OF, SEQUENCE OF */
		int sktag, skaclass;
		char sk_eoc;
		/* First work out expected inner tag value */
		if(flags & ASN1_TFLG_IMPTAG) {
			sktag = tt->tag;
			skaclass = aclass;
		} else {
			skaclass = V_ASN1_UNIVERSAL;
			if(flags & ASN1_TFLG_SET_OF) sktag = V_ASN1_SET;
			else sktag = V_ASN1_SEQUENCE;
		}
		/* Get the tag */
		ret = asn1_check_tlen(&len, NULL, NULL, &sk_eoc, NULL, &p, len, sktag, skaclass, opt, ctx);
		if(!ret) {
			ASN1err(ASN1_F_ASN1_TEMPLATE_EX_D2I, ERR_R_NESTED_ASN1_ERROR);
			return 0;
		} else if(ret == -1) return -1;
		if(!*val) *val = (ASN1_VALUE *)sk_new_null();
		else {
			/* We've got a valid STACK: free up any items present */
			STACK *sktmp = (STACK *)*val;
			ASN1_VALUE *vtmp;
			while(sk_num(sktmp) > 0) {
				vtmp = (ASN1_VALUE *)sk_pop(sktmp);
521
				ASN1_item_ex_free(&vtmp, ASN1_ITEM_ptr(tt->item));
D
 
Dr. Stephen Henson 已提交
522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543
			}
		}
				
		if(!*val) {
			ASN1err(ASN1_F_ASN1_TEMPLATE_EX_D2I, ERR_R_MALLOC_FAILURE);
			goto err;
		}
		/* Read as many items as we can */
		while(len > 0) {
			ASN1_VALUE *skfield;
			q = p;
			/* See if EOC found */
			if(asn1_check_eoc(&p, len)) {
				if(!sk_eoc) {
					ASN1err(ASN1_F_ASN1_TEMPLATE_D2I, ASN1_R_UNEXPECTED_EOC);
					goto err;
				}
				len -= p - q;
				sk_eoc = 0;
				break;
			}
			skfield = NULL;
544
			if(!ASN1_item_ex_d2i(&skfield, &p, len, ASN1_ITEM_ptr(tt->item), -1, 0, 0, ctx)) {
D
 
Dr. Stephen Henson 已提交
545 546 547 548 549 550 551 552 553 554 555 556 557 558 559
				ASN1err(ASN1_F_ASN1_TEMPLATE_D2I, ERR_R_NESTED_ASN1_ERROR);
				goto err;
			}
			len -= p - q;
			if(!sk_push((STACK *)*val, (char *)skfield)) {
				ASN1err(ASN1_F_ASN1_TEMPLATE_D2I, ERR_R_MALLOC_FAILURE);
				goto err;
			}
		}
		if(sk_eoc) {
			ASN1err(ASN1_F_ASN1_TEMPLATE_D2I, ASN1_R_MISSING_EOC);
			goto err;
		}
	} else if(flags & ASN1_TFLG_IMPTAG) {
		/* IMPLICIT tagging */
560
		ret = ASN1_item_ex_d2i(val, &p, len, ASN1_ITEM_ptr(tt->item), tt->tag, aclass, opt, ctx);
D
 
Dr. Stephen Henson 已提交
561 562 563 564 565 566
		if(!ret) {
			ASN1err(ASN1_F_ASN1_TEMPLATE_D2I, ERR_R_NESTED_ASN1_ERROR);
			goto err;
		} else if(ret == -1) return -1;
	} else {
		/* Nothing special */
567
		ret = ASN1_item_ex_d2i(val, &p, len, ASN1_ITEM_ptr(tt->item), -1, 0, opt, ctx);
D
 
Dr. Stephen Henson 已提交
568 569 570 571 572 573 574 575 576 577 578 579 580 581 582
		if(!ret) {
			ASN1err(ASN1_F_ASN1_TEMPLATE_D2I, ERR_R_NESTED_ASN1_ERROR);
			goto err;
		} else if(ret == -1) return -1;
	}

	*in = p;
	return 1;

	err:
	ASN1_template_free(val, tt);
	*val = NULL;
	return 0;
}

583
static int asn1_d2i_ex_primitive(ASN1_VALUE **pval, const unsigned char **in, long inlen, 
D
 
Dr. Stephen Henson 已提交
584 585 586 587 588 589
						const ASN1_ITEM *it,
						int tag, int aclass, char opt, ASN1_TLC *ctx)
{
	int ret = 0, utype;
	long plen;
	char cst, inf, free_cont = 0;
590
	const unsigned char *p;
D
 
Dr. Stephen Henson 已提交
591
	BUF_MEM buf;
592
	const unsigned char *cont = NULL;
D
 
Dr. Stephen Henson 已提交
593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635
	long len; 
	if(!pval) {
		ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, ASN1_R_ILLEGAL_NULL);
		return 0; /* Should never happen */
	}

	if(it->itype == ASN1_ITYPE_MSTRING) {
		utype = tag;
		tag = -1;
	} else utype = it->utype;

	if(utype == V_ASN1_ANY) {
		/* If type is ANY need to figure out type from tag */
		unsigned char oclass;
		if(tag >= 0) {
			ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, ASN1_R_ILLEGAL_TAGGED_ANY);
			return 0;
		}
		if(opt) {
			ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, ASN1_R_ILLEGAL_OPTIONAL_ANY);
			return 0;
		}
		p = *in;
		ret = asn1_check_tlen(NULL, &utype, &oclass, NULL, NULL, &p, inlen, -1, 0, 0, ctx);
		if(!ret) {
			ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, ERR_R_NESTED_ASN1_ERROR);
			return 0;
		}
		if(oclass != V_ASN1_UNIVERSAL) utype = V_ASN1_OTHER;
	}
	if(tag == -1) {
		tag = utype;
		aclass = V_ASN1_UNIVERSAL;
	}
	p = *in;
	/* Check header */
	ret = asn1_check_tlen(&plen, NULL, NULL, &inf, &cst, &p, inlen, tag, aclass, opt, ctx);
	if(!ret) {
		ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, ERR_R_NESTED_ASN1_ERROR);
		return 0;
	} else if(ret == -1) return -1;
	/* SEQUENCE, SET and "OTHER" are left in encoded form */
	if((utype == V_ASN1_SEQUENCE) || (utype == V_ASN1_SET) || (utype == V_ASN1_OTHER)) {
D
 
Dr. Stephen Henson 已提交
636 637 638 639 640
		/* Clear context cache for type OTHER because the auto clear when
		 * we have a exact match wont work
		 */
		if(utype == V_ASN1_OTHER) {
			asn1_tlc_clear(ctx);
D
 
Dr. Stephen Henson 已提交
641
		/* SEQUENCE and SET must be constructed */
D
 
Dr. Stephen Henson 已提交
642
		} else if(!cst) {
D
 
Dr. Stephen Henson 已提交
643 644 645 646 647 648 649
			ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, ASN1_R_TYPE_NOT_CONSTRUCTED);
			return 0;
		}

		cont = *in;
		/* If indefinite length constructed find the real end */
		if(inf) {
D
Dr. Stephen Henson 已提交
650
			if(!asn1_collect(NULL, &p, plen, inf, -1, -1)) goto err;
D
 
Dr. Stephen Henson 已提交
651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666
			len = p - cont;
		} else {
			len = p - cont + plen;
			p += plen;
			buf.data = NULL;
		}
	} else if(cst) {
		buf.length = 0;
		buf.max = 0;
		buf.data = NULL;
		/* Should really check the internal tags are correct but
		 * some things may get this wrong. The relevant specs
		 * say that constructed string types should be OCTET STRINGs
		 * internally irrespective of the type. So instead just check
		 * for UNIVERSAL class and ignore the tag.
		 */
D
Dr. Stephen Henson 已提交
667
		if(!asn1_collect(&buf, &p, plen, inf, -1, V_ASN1_UNIVERSAL)) goto err;
D
 
Dr. Stephen Henson 已提交
668
		len = buf.length;
D
Dr. Stephen Henson 已提交
669
		/* Append a final null to string */
670
		if(!BUF_MEM_grow_clean(&buf, len + 1)) {
D
Dr. Stephen Henson 已提交
671 672 673 674
			ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, ERR_R_MALLOC_FAILURE);
			return 0;
		}
		buf.data[len] = 0;
675
		cont = (const unsigned char *)buf.data;
D
 
Dr. Stephen Henson 已提交
676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694
		free_cont = 1;
	} else {
		cont = p;
		len = plen;
		p += plen;
	}

	/* We now have content length and type: translate into a structure */
	if(!asn1_ex_c2i(pval, cont, len, utype, &free_cont, it)) goto err;

	*in = p;
	ret = 1;
	err:
	if(free_cont && buf.data) OPENSSL_free(buf.data);
	return ret;
}

/* Translate ASN1 content octets into a structure */

695
int asn1_ex_c2i(ASN1_VALUE **pval, const unsigned char *cont, int len, int utype, char *free_cont, const ASN1_ITEM *it)
D
 
Dr. Stephen Henson 已提交
696
{
697
	ASN1_VALUE **opval = NULL;
D
 
Dr. Stephen Henson 已提交
698 699 700 701
	ASN1_STRING *stmp;
	ASN1_TYPE *typ = NULL;
	int ret = 0;
	const ASN1_PRIMITIVE_FUNCS *pf;
702
	ASN1_INTEGER **tint;
D
 
Dr. Stephen Henson 已提交
703 704 705 706 707 708 709
	pf = it->funcs;
	if(pf && pf->prim_c2i) return pf->prim_c2i(pval, cont, len, utype, free_cont, it);
	/* If ANY type clear type and set pointer to internal value */
	if(it->utype == V_ASN1_ANY) {
		if(!*pval) {
			typ = ASN1_TYPE_new();
			*pval = (ASN1_VALUE *)typ;
D
 
Dr. Stephen Henson 已提交
710
		} else typ = (ASN1_TYPE *)*pval;
D
 
Dr. Stephen Henson 已提交
711
		if(utype != typ->type) ASN1_TYPE_set(typ, utype, NULL);
712
		opval = pval;
D
 
Dr. Stephen Henson 已提交
713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746
		pval = (ASN1_VALUE **)&typ->value.ptr;
	}
	switch(utype) {
		case V_ASN1_OBJECT:
		if(!c2i_ASN1_OBJECT((ASN1_OBJECT **)pval, &cont, len)) goto err;
		break;

		case V_ASN1_NULL:
		if(len) {
			ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, ASN1_R_NULL_IS_WRONG_LENGTH);
			goto err;
		}
		*pval = (ASN1_VALUE *)1;
		break;

		case V_ASN1_BOOLEAN:
		if(len != 1) {
			ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, ASN1_R_BOOLEAN_IS_WRONG_LENGTH);
			goto err;
		} else {
			ASN1_BOOLEAN *tbool;
			tbool = (ASN1_BOOLEAN *)pval;
			*tbool = *cont;
		}
		break;

		case V_ASN1_BIT_STRING:
		if(!c2i_ASN1_BIT_STRING((ASN1_BIT_STRING **)pval, &cont, len)) goto err;
		break;

		case V_ASN1_INTEGER:
		case V_ASN1_NEG_INTEGER:
		case V_ASN1_ENUMERATED:
		case V_ASN1_NEG_ENUMERATED:
747 748 749 750
		tint = (ASN1_INTEGER **)pval;
		if(!c2i_ASN1_INTEGER(tint, &cont, len)) goto err;
		/* Fixup type to match the expected form */
		(*tint)->type = utype | ((*tint)->type & V_ASN1_NEG);
D
 
Dr. Stephen Henson 已提交
751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785
		break;

		case V_ASN1_OCTET_STRING:
		case V_ASN1_NUMERICSTRING:
		case V_ASN1_PRINTABLESTRING:
		case V_ASN1_T61STRING:
		case V_ASN1_VIDEOTEXSTRING:
		case V_ASN1_IA5STRING:
		case V_ASN1_UTCTIME:
		case V_ASN1_GENERALIZEDTIME:
		case V_ASN1_GRAPHICSTRING:
		case V_ASN1_VISIBLESTRING:
		case V_ASN1_GENERALSTRING:
		case V_ASN1_UNIVERSALSTRING:
		case V_ASN1_BMPSTRING:
		case V_ASN1_UTF8STRING:
		case V_ASN1_OTHER:
		case V_ASN1_SET:
		case V_ASN1_SEQUENCE:
		default:
		/* All based on ASN1_STRING and handled the same */
		if(!*pval) {
			stmp = ASN1_STRING_type_new(utype);
			if(!stmp) {
				ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, ERR_R_MALLOC_FAILURE);
				goto err;
			}
			*pval = (ASN1_VALUE *)stmp;
		} else {
			stmp = (ASN1_STRING *)*pval;
			stmp->type = utype;
		}
		/* If we've already allocated a buffer use it */
		if(*free_cont) {
			if(stmp->data) OPENSSL_free(stmp->data);
786
			stmp->data = (unsigned char *)cont; /* UGLY CAST! RL */
D
 
Dr. Stephen Henson 已提交
787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803
			stmp->length = len;
			*free_cont = 0;
		} else {
			if(!ASN1_STRING_set(stmp, cont, len)) {
				ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, ERR_R_MALLOC_FAILURE);
				ASN1_STRING_free(stmp);	
				*pval = NULL;
				goto err;
			}
		}
		break;
	}
	/* If ASN1_ANY and NULL type fix up value */
	if(typ && utype==V_ASN1_NULL) typ->value.ptr = NULL;

	ret = 1;
	err:
804 805 806 807 808 809
	if(!ret)
		{
		ASN1_TYPE_free(typ);
		if (opval)
			*opval = NULL;
		}
D
 
Dr. Stephen Henson 已提交
810 811 812 813 814 815 816 817 818 819 820
	return ret;
}

/* This function collects the asn1 data from a constructred string
 * type into a buffer. The values of 'in' and 'len' should refer
 * to the contents of the constructed type and 'inf' should be set
 * if it is indefinite length. If 'buf' is NULL then we just want
 * to find the end of the current structure: useful for indefinite
 * length constructed stuff.
 */

821
static int asn1_collect(BUF_MEM *buf, const unsigned char **in, long len, char inf, int tag, int aclass)
D
 
Dr. Stephen Henson 已提交
822
{
823
	const unsigned char *p, *q;
D
 
Dr. Stephen Henson 已提交
824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864
	long plen;
	char cst, ininf;
	p = *in;
	inf &= 1;
	/* If no buffer and not indefinite length constructed just pass over the encoded data */
	if(!buf && !inf) {
		*in += len;
		return 1;
	}
	while(len > 0) {
		q = p;
		/* Check for EOC */
		if(asn1_check_eoc(&p, len)) {
			/* EOC is illegal outside indefinite length constructed form */
			if(!inf) {
				ASN1err(ASN1_F_ASN1_COLLECT, ASN1_R_UNEXPECTED_EOC);
				return 0;
			}
			inf = 0;
			break;
		}
		if(!asn1_check_tlen(&plen, NULL, NULL, &ininf, &cst, &p, len, tag, aclass, 0, NULL)) {
			ASN1err(ASN1_F_ASN1_COLLECT, ERR_R_NESTED_ASN1_ERROR);
			return 0;
		}
		/* If indefinite length constructed update max length */
		if(cst) {
			if(!asn1_collect(buf, &p, plen, ininf, tag, aclass)) return 0;
		} else {
			if(!collect_data(buf, &p, plen)) return 0;
		}
		len -= p - q;
	}
	if(inf) {
		ASN1err(ASN1_F_ASN1_COLLECT, ASN1_R_MISSING_EOC);
		return 0;
	}
	*in = p;
	return 1;
}

865
static int collect_data(BUF_MEM *buf, const unsigned char **p, long plen)
D
 
Dr. Stephen Henson 已提交
866 867 868 869
{
		int len;
		if(buf) {
			len = buf->length;
870
			if(!BUF_MEM_grow_clean(buf, len + plen)) {
D
 
Dr. Stephen Henson 已提交
871 872 873 874 875 876 877 878 879 880 881
				ASN1err(ASN1_F_COLLECT_DATA, ERR_R_MALLOC_FAILURE);
				return 0;
			}
			memcpy(buf->data + len, *p, plen);
		}
		*p += plen;
		return 1;
}

/* Check for ASN1 EOC and swallow it if found */

882
static int asn1_check_eoc(const unsigned char **in, long len)
D
 
Dr. Stephen Henson 已提交
883
{
884
	const unsigned char *p;
D
 
Dr. Stephen Henson 已提交
885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901
	if(len < 2) return 0;
	p = *in;
	if(!p[0] && !p[1]) {
		*in += 2;
		return 1;
	}
	return 0;
}

/* Check an ASN1 tag and length: a bit like ASN1_get_object
 * but it sets the length for indefinite length constructed
 * form, we don't know the exact length but we can set an
 * upper bound to the amount of data available minus the
 * header length just read.
 */

static int asn1_check_tlen(long *olen, int *otag, unsigned char *oclass, char *inf, char *cst,
902
		const unsigned char **in, long len, int exptag, int expclass, char opt, ASN1_TLC *ctx)
D
 
Dr. Stephen Henson 已提交
903 904 905 906
{
	int i;
	int ptag, pclass;
	long plen;
907
	const unsigned char *p, *q;
D
 
Dr. Stephen Henson 已提交
908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925
	p = *in;
	q = p;

	if(ctx && ctx->valid) {
		i = ctx->ret;
		plen = ctx->plen;
		pclass = ctx->pclass;
		ptag = ctx->ptag;
		p += ctx->hdrlen;
	} else {
		i = ASN1_get_object(&p, &plen, &ptag, &pclass, len);
		if(ctx) {
			ctx->ret = i;
			ctx->plen = plen;
			ctx->pclass = pclass;
			ctx->ptag = ptag;
			ctx->hdrlen = p - q;
			ctx->valid = 1;
D
 
Dr. Stephen Henson 已提交
926 927
			/* If definite length, and no error, length +
			 * header can't exceed total amount of data available. 
D
 
Dr. Stephen Henson 已提交
928
			 */
D
 
Dr. Stephen Henson 已提交
929
			if(!(i & 0x81) && ((plen + ctx->hdrlen) > len)) {
D
 
Dr. Stephen Henson 已提交
930 931 932 933
				ASN1err(ASN1_F_ASN1_CHECK_TLEN, ASN1_R_TOO_LONG);
				asn1_tlc_clear(ctx);
				return 0;
			}
D
 
Dr. Stephen Henson 已提交
934 935
		}
	}
D
 
Dr. Stephen Henson 已提交
936

D
 
Dr. Stephen Henson 已提交
937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968
	if(i & 0x80) {
		ASN1err(ASN1_F_ASN1_CHECK_TLEN, ASN1_R_BAD_OBJECT_HEADER);
		asn1_tlc_clear(ctx);
		return 0;
	}
	if(exptag >= 0) {
		if((exptag != ptag) || (expclass != pclass)) {
			/* If type is OPTIONAL, not an error, but indicate missing
			 * type.
			 */
			if(opt) return -1;
			asn1_tlc_clear(ctx);
			ASN1err(ASN1_F_ASN1_CHECK_TLEN, ASN1_R_WRONG_TAG);
			return 0;
		}
		/* We have a tag and class match, so assume we are going to do something with it */
		asn1_tlc_clear(ctx);
	}

	if(i & 1) plen = len - (p - q);

	if(inf) *inf = i & 1;

	if(cst) *cst = i & V_ASN1_CONSTRUCTED;

	if(olen) *olen = plen;
	if(oclass) *oclass = pclass;
	if(otag) *otag = ptag;

	*in = p;
	return 1;
}