1 /*	$NetBSD: decode.c,v 1.3 2021/08/14 16:14:55 christos Exp $	*/
2 
3 /* decode.c - ber input decoding routines */
4 /* $OpenLDAP$ */
5 /* This work is part of OpenLDAP Software <http://www.openldap.org/>.
6  *
7  * Copyright 1998-2021 The OpenLDAP Foundation.
8  * All rights reserved.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted only as authorized by the OpenLDAP
12  * Public License.
13  *
14  * A copy of this license is available in the file LICENSE in the
15  * top-level directory of the distribution or, alternatively, at
16  * <http://www.OpenLDAP.org/license.html>.
17  */
18 /* Portions Copyright (c) 1990 Regents of the University of Michigan.
19  * All rights reserved.
20  *
21  * Redistribution and use in source and binary forms are permitted
22  * provided that this notice is preserved and that due credit is given
23  * to the University of Michigan at Ann Arbor. The name of the University
24  * may not be used to endorse or promote products derived from this
25  * software without specific prior written permission. This software
26  * is provided ``as is'' without express or implied warranty.
27  */
28 /* ACKNOWLEDGEMENTS:
29  * This work was originally developed by the University of Michigan
30  * (as part of U-MICH LDAP).
31  */
32 
33 #include <sys/cdefs.h>
34 __RCSID("$NetBSD: decode.c,v 1.3 2021/08/14 16:14:55 christos Exp $");
35 
36 #include "portable.h"
37 
38 #include <stdio.h>
39 
40 #include <ac/stdlib.h>
41 #include <ac/stdarg.h>
42 #include <ac/string.h>
43 #include <ac/socket.h>
44 
45 #include "lber-int.h"
46 
47 
48 /* out->bv_len should be the buffer size on input */
49 int
ber_decode_oid(BerValue * in,BerValue * out)50 ber_decode_oid( BerValue *in, BerValue *out )
51 {
52 	const unsigned char *der;
53 	unsigned long val;
54 	unsigned val1;
55 	ber_len_t i;
56 	char *ptr;
57 
58 	assert( in != NULL );
59 	assert( out != NULL );
60 
61 	/* need 4 chars/inbyte + \0 for input={7f 7f 7f...} */
62 	if ( !out->bv_val || (out->bv_len+3)/4 <= in->bv_len )
63 		return -1;
64 
65 	ptr = NULL;
66 	der = (unsigned char *) in->bv_val;
67 	val = 0;
68 	for ( i=0; i < in->bv_len; i++ ) {
69 		val |= der[i] & 0x7f;
70 		if ( !( der[i] & 0x80 )) {
71 			if ( ptr == NULL ) {
72 				/* Initial "x.y": val=x*40+y, x<=2, y<40 if x<2 */
73 				ptr = out->bv_val;
74 				val1 = (val < 80 ? val/40 : 2);
75 				val -= val1*40;
76 				ptr += sprintf( ptr, "%u", val1 );
77 			}
78 			ptr += sprintf( ptr, ".%lu", val );
79 			val = 0;
80 		} else if ( val - 1UL < LBER_OID_COMPONENT_MAX >> 7 ) {
81 			val <<= 7;
82 		} else {
83 			/* val would overflow, or is 0 from invalid initial 0x80 octet */
84 			return -1;
85 		}
86 	}
87 	if ( ptr == NULL || val != 0 )
88 		return -1;
89 
90 	out->bv_len = ptr - out->bv_val;
91 	return 0;
92 }
93 
94 /* Return tag, with *bv = rest of element (starting at length octets) */
95 static ber_tag_t
ber_tag_and_rest(const BerElement * ber,struct berval * bv)96 ber_tag_and_rest( const BerElement *ber, struct berval *bv )
97 {
98 	ber_tag_t	tag;
99 	ptrdiff_t	rest;
100 	unsigned char	*ptr;
101 
102 	assert( ber != NULL );
103 	assert( LBER_VALID( ber ) );
104 
105 	ptr = (unsigned char *) ber->ber_ptr;
106 	rest = (unsigned char *) ber->ber_end - ptr;
107 	if ( rest <= 0 ) {
108 		goto fail;
109 	}
110 
111 	tag = ber->ber_tag;
112 	if ( (char *) ptr == ber->ber_buf ) {
113 		tag = *ptr;
114 	}
115 	ptr++;
116 	rest--;
117 	if ( (tag & LBER_BIG_TAG_MASK) != LBER_BIG_TAG_MASK ) {
118 		goto done;
119 	}
120 
121 	do {
122 		if ( rest <= 0 ) {
123 			break;
124 		}
125 		tag <<= 8;
126 		tag |= *ptr++ & 0xffU;
127 		rest--;
128 
129 		if ( ! (tag & LBER_MORE_TAG_MASK) ) {
130 			goto done;
131 		}
132 	} while ( tag <= (ber_tag_t)-1 / 256 );
133 
134  fail:
135 	/* Error or unsupported tag size */
136 	tag = LBER_DEFAULT;
137 
138  done:
139 	bv->bv_len = rest;
140 	bv->bv_val = (char *) ptr;
141 	return tag;
142 }
143 
144 /* Return the tag - LBER_DEFAULT returned means trouble */
145 ber_tag_t
ber_get_tag(BerElement * ber)146 ber_get_tag( BerElement *ber )
147 {
148 	struct berval bv;
149 	ber_tag_t tag = ber_tag_and_rest( ber, &bv );
150 
151 	ber->ber_ptr = bv.bv_val;
152 	return tag;
153 }
154 
155 /* Return next element's tag and point *bv at its contents in-place */
156 ber_tag_t
ber_peek_element(const BerElement * ber,struct berval * bv)157 ber_peek_element( const BerElement *ber, struct berval *bv )
158 {
159 	ber_tag_t	tag;
160 	ber_len_t	len, rest;
161 	unsigned	i;
162 	unsigned char *ptr;
163 
164 	assert( bv != NULL );
165 
166 	/*
167 	 * Any ber element looks like this: tag length contents.
168 	 * Assuming everything's ok, we return the tag, and point
169 	 * bv at the contents.
170 	 *
171 	 * Assumptions:
172 	 *	1) definite lengths
173 	 *	2) primitive encodings used whenever possible
174 	 */
175 
176 	len = 0;
177 
178 	/*
179 	 * First, we read the tag.
180 	 */
181 	tag = ber_tag_and_rest( ber, bv );
182 
183 	rest = bv->bv_len;
184 	ptr = (unsigned char *) bv->bv_val;
185 	if ( tag == LBER_DEFAULT || rest == 0 ) {
186 		goto fail;
187 	}
188 
189 	/*
190 	 * Next, read the length.  The first octet determines the length
191 	 * of the length.	If bit 8 is 0, the length is the short form,
192 	 * otherwise if the octet != 0x80 it's the long form, otherwise
193 	 * the ber element has the unsupported indefinite-length format.
194 	 * Lengths that do not fit in a ber_len_t are not accepted.
195 	 */
196 
197 	len = *ptr++;
198 	rest--;
199 
200 	if ( len & 0x80U ) {
201 		len &= 0x7fU;
202 		if ( len - 1U > sizeof(ber_len_t) - 1U || rest < len ) {
203 			/* Indefinite-length/too long length/not enough data */
204 			goto fail;
205 		}
206 
207 		rest -= len;
208 		i = len;
209 		for( len = *ptr++ & 0xffU; --i; len |= *ptr++ & 0xffU ) {
210 			len <<= 8;
211 		}
212 	}
213 
214 	/* BER element should have enough data left */
215 	if( len > rest ) {
216 	fail:
217 		tag = LBER_DEFAULT;
218 	}
219 
220 	bv->bv_len = len;
221 	bv->bv_val = (char *) ptr;
222 	return tag;
223 }
224 
225 /* Move past next element, point *bv at it in-place, and return its tag.
226  * The caller may \0-terminate *bv, as next octet is saved in ber->ber_tag.
227  * Similar to ber_get_stringbv(ber, bv, LBER_BV_NOTERM) except on error.
228  */
229 ber_tag_t
ber_skip_element(BerElement * ber,struct berval * bv)230 ber_skip_element( BerElement *ber, struct berval *bv )
231 {
232 	ber_tag_t tag = ber_peek_element( ber, bv );
233 
234 	if ( tag != LBER_DEFAULT ) {
235 		ber->ber_ptr = bv->bv_val + bv->bv_len;
236 		ber->ber_tag = *(unsigned char *) ber->ber_ptr;
237 	}
238 
239 	return tag;
240 }
241 
242 /* Move past next element, point *bv at the complete element in-place, and
243  * return its tag. The caller may \0-terminate *bv, as next octet is saved in
244  * ber->ber_tag. Similar to ber_skip_element(ber, bv) except the tag+length
245  * header is also included in *bv.
246  */
247 ber_tag_t
ber_skip_raw(BerElement * ber,struct berval * bv)248 ber_skip_raw( BerElement *ber, struct berval *bv )
249 {
250 	char		*val = ber->ber_ptr;
251 	ber_tag_t	tag = ber_skip_element( ber, bv );
252 
253 	if ( tag != LBER_DEFAULT ) {
254 		bv->bv_len += bv->bv_val - val;
255 		bv->bv_val = val;
256 	}
257 
258 	return tag;
259 }
260 
261 ber_tag_t
ber_peek_tag(BerElement * ber,ber_len_t * len)262 ber_peek_tag(
263 	BerElement *ber,
264 	ber_len_t *len )
265 {
266 	struct berval bv;
267 	ber_tag_t tag = ber_peek_element( ber, &bv );
268 
269 	*len = bv.bv_len;
270 	return tag;
271 }
272 
273 ber_tag_t
ber_skip_tag(BerElement * ber,ber_len_t * lenp)274 ber_skip_tag( BerElement *ber, ber_len_t *lenp )
275 {
276 	struct berval bv;
277 	ber_tag_t tag = ber_peek_element( ber, &bv );
278 
279 	ber->ber_ptr = bv.bv_val;
280 	ber->ber_tag = *(unsigned char *) ber->ber_ptr;
281 
282 	*lenp = bv.bv_len;
283 	return tag;
284 }
285 
286 ber_tag_t
ber_get_int(BerElement * ber,ber_int_t * num)287 ber_get_int(
288 	BerElement *ber,
289 	ber_int_t *num )
290 {
291 	struct berval bv;
292 	ber_tag_t	tag = ber_skip_element( ber, &bv );
293 
294 	if ( tag == LBER_DEFAULT ) {
295 		return tag;
296 	}
297 
298 	return ber_decode_int( &bv, num ) ? LBER_DEFAULT : tag;
299 }
300 
301 int
ber_decode_int(const struct berval * bv,ber_int_t * num)302 ber_decode_int( const struct berval *bv, ber_int_t *num )
303 {
304 	ber_len_t	len = bv->bv_len;
305 	if ( len > sizeof(ber_int_t) )
306 		return -1;
307 
308 	assert( num != NULL );
309 
310 	/* parse two's complement integer */
311 	if( len ) {
312 		unsigned char *buf = (unsigned char *) bv->bv_val;
313 		ber_len_t i;
314 		ber_int_t netnum = buf[0] & 0xff;
315 
316 		/* sign extend */
317 		netnum = (netnum ^ 0x80) - 0x80;
318 
319 		/* shift in the bytes */
320 		for( i = 1; i < len; i++ ) {
321 			netnum = (netnum << 8 ) | buf[i];
322 		}
323 
324 		*num = netnum;
325 
326 	} else {
327 		*num = 0;
328 	}
329 
330 	return 0;
331 }
332 
333 ber_tag_t
ber_get_enum(BerElement * ber,ber_int_t * num)334 ber_get_enum(
335 	BerElement *ber,
336 	ber_int_t *num )
337 {
338 	return ber_get_int( ber, num );
339 }
340 
341 ber_tag_t
ber_get_stringb(BerElement * ber,char * buf,ber_len_t * len)342 ber_get_stringb(
343 	BerElement *ber,
344 	char *buf,
345 	ber_len_t *len )
346 {
347 	struct berval bv;
348 	ber_tag_t	tag;
349 
350 	if ( (tag = ber_skip_element( ber, &bv )) == LBER_DEFAULT ) {
351 		return LBER_DEFAULT;
352 	}
353 
354 	/* must fit within allocated space with termination */
355 	if ( bv.bv_len >= *len ) {
356 		return LBER_DEFAULT;
357 	}
358 
359 	memcpy( buf, bv.bv_val, bv.bv_len );
360 	buf[bv.bv_len] = '\0';
361 
362 	*len = bv.bv_len;
363 	return tag;
364 }
365 
366 /* Definitions for get_string vector
367  *
368  * ChArray, BvArray, and BvVec are self-explanatory.
369  * BvOff is a struct berval embedded in an array of larger structures
370  * of siz bytes at off bytes from the beginning of the struct.
371  */
372 enum bgbvc { ChArray, BvArray, BvVec, BvOff };
373 
374 /* Use this single cookie for state, to keep actual
375  * stack use to the absolute minimum.
376  */
377 typedef struct bgbvr {
378 	const enum bgbvc choice;
379 	const int option;	/* (ALLOC unless BvOff) | (STRING if ChArray) */
380 	ber_len_t siz;		/* input array element size, output count */
381 	ber_len_t off;		/* BvOff offset to the struct berval */
382 	void *result;
383 } bgbvr;
384 
385 static ber_tag_t
ber_get_stringbvl(BerElement * ber,bgbvr * b)386 ber_get_stringbvl( BerElement *ber, bgbvr *b )
387 {
388 	int i = 0, n;
389 	ber_tag_t tag;
390 	ber_len_t tot_size = 0, siz = b->siz;
391 	char *last, *orig;
392 	struct berval bv, *bvp = NULL;
393 	union stringbvl_u {
394 		char **ca;				/* ChArray */
395 		BerVarray ba;			/* BvArray */
396 		struct berval **bv;		/* BvVec */
397 		char *bo;				/* BvOff */
398 	} res;
399 
400 	tag = ber_skip_tag( ber, &bv.bv_len );
401 
402 	if ( tag != LBER_DEFAULT ) {
403 		tag = 0;
404 		orig = ber->ber_ptr;
405 		last = orig + bv.bv_len;
406 
407 		for ( ; ber->ber_ptr < last; i++, tot_size += siz ) {
408 			if ( ber_skip_element( ber, &bv ) == LBER_DEFAULT )
409 				break;
410 		}
411 		if ( ber->ber_ptr != last ) {
412 			i = 0;
413 			tag = LBER_DEFAULT;
414 		}
415 
416 		ber->ber_ptr = orig;
417 		ber->ber_tag = *(unsigned char *) orig;
418 	}
419 
420 	b->siz = i;
421 	if ( i == 0 ) {
422 		return tag;
423 	}
424 
425 	/* Allocate and NULL-terminate the result vector */
426 	b->result = ber_memalloc_x( tot_size + siz, ber->ber_memctx );
427 	if ( b->result == NULL ) {
428 		return LBER_DEFAULT;
429 	}
430 	switch (b->choice) {
431 	case ChArray:
432 		res.ca = b->result;
433 		res.ca[i] = NULL;
434 		break;
435 	case BvArray:
436 		res.ba = b->result;
437 		res.ba[i].bv_val = NULL;
438 		break;
439 	case BvVec:
440 		res.bv = b->result;
441 		res.bv[i] = NULL;
442 		break;
443 	case BvOff:
444 		res.bo = (char *) b->result + b->off;
445 		((struct berval *) (res.bo + tot_size))->bv_val = NULL;
446 		tot_size = 0;
447 		break;
448 	}
449 
450 	n = 0;
451 	do {
452 		tag = ber_get_stringbv( ber, &bv, b->option );
453 		if ( tag == LBER_DEFAULT ) {
454 			goto failed;
455 		}
456 
457 		/* store my result */
458 		switch (b->choice) {
459 		case ChArray:
460 			res.ca[n] = bv.bv_val;
461 			break;
462 		case BvArray:
463 			res.ba[n] = bv;
464 			break;
465 		case BvVec:
466 			bvp = ber_memalloc_x( sizeof( struct berval ),
467 				ber->ber_memctx );
468 			if ( !bvp ) {
469 				ber_memfree_x( bv.bv_val, ber->ber_memctx );
470 				goto failed;
471 			}
472 			res.bv[n] = bvp;
473 			*bvp = bv;
474 			break;
475 		case BvOff:
476 			*(struct berval *)(res.bo + tot_size) = bv;
477 			tot_size += siz;
478 			break;
479 		}
480 	} while (++n < i);
481 	return tag;
482 
483 failed:
484 	if (b->choice != BvOff) { /* BvOff does not have LBER_BV_ALLOC set */
485 		while (--n >= 0) {
486 			switch(b->choice) {
487 			case ChArray:
488 				ber_memfree_x(res.ca[n], ber->ber_memctx);
489 				break;
490 			case BvArray:
491 				ber_memfree_x(res.ba[n].bv_val, ber->ber_memctx);
492 				break;
493 			case BvVec:
494 				ber_memfree_x(res.bv[n]->bv_val, ber->ber_memctx);
495 				ber_memfree_x(res.bv[n], ber->ber_memctx);
496 				break;
497 			default:
498 				break;
499 			}
500 		}
501 	}
502 	ber_memfree_x(b->result, ber->ber_memctx);
503 	b->result = NULL;
504 	return LBER_DEFAULT;
505 }
506 
507 ber_tag_t
ber_get_stringbv(BerElement * ber,struct berval * bv,int option)508 ber_get_stringbv( BerElement *ber, struct berval *bv, int option )
509 {
510 	ber_tag_t	tag;
511 	char		*data;
512 
513 	tag = ber_skip_element( ber, bv );
514 	if ( tag == LBER_DEFAULT ||
515 		(( option & LBER_BV_STRING ) &&
516 		 bv->bv_len && memchr( bv->bv_val, 0, bv->bv_len - 1 )))
517 	{
518 		bv->bv_val = NULL;
519 		return LBER_DEFAULT;
520 	}
521 
522 	data = bv->bv_val;
523 	if ( option & LBER_BV_ALLOC ) {
524 		bv->bv_val = (char *) ber_memalloc_x( bv->bv_len + 1,
525 			ber->ber_memctx );
526 		if ( bv->bv_val == NULL ) {
527 			return LBER_DEFAULT;
528 		}
529 
530 		if ( bv->bv_len != 0 ) {
531 			memcpy( bv->bv_val, data, bv->bv_len );
532 		}
533 		data = bv->bv_val;
534 	}
535 	if ( !( option & LBER_BV_NOTERM ))
536 		data[bv->bv_len] = '\0';
537 
538 	return tag;
539 }
540 
541 ber_tag_t
ber_get_stringbv_null(BerElement * ber,struct berval * bv,int option)542 ber_get_stringbv_null( BerElement *ber, struct berval *bv, int option )
543 {
544 	ber_tag_t	tag;
545 	char		*data;
546 
547 	tag = ber_skip_element( ber, bv );
548 	if ( tag == LBER_DEFAULT || bv->bv_len == 0 ) {
549 		bv->bv_val = NULL;
550 		return tag;
551 	}
552 
553 	if (( option & LBER_BV_STRING ) &&
554 		memchr( bv->bv_val, 0, bv->bv_len - 1 ))
555 	{
556 		bv->bv_val = NULL;
557 		return LBER_DEFAULT;
558 	}
559 
560 	data = bv->bv_val;
561 	if ( option & LBER_BV_ALLOC ) {
562 		bv->bv_val = (char *) ber_memalloc_x( bv->bv_len + 1,
563 			ber->ber_memctx );
564 		if ( bv->bv_val == NULL ) {
565 			return LBER_DEFAULT;
566 		}
567 
568 		memcpy( bv->bv_val, data, bv->bv_len );
569 		data = bv->bv_val;
570 	}
571 	if ( !( option & LBER_BV_NOTERM ))
572 		data[bv->bv_len] = '\0';
573 
574 	return tag;
575 }
576 
577 ber_tag_t
ber_get_stringa(BerElement * ber,char ** buf)578 ber_get_stringa( BerElement *ber, char **buf )
579 {
580 	BerValue	bv;
581 	ber_tag_t	tag;
582 
583 	assert( buf != NULL );
584 
585 	tag = ber_get_stringbv( ber, &bv, LBER_BV_ALLOC | LBER_BV_STRING );
586 	*buf = bv.bv_val;
587 
588 	return tag;
589 }
590 
591 ber_tag_t
ber_get_stringa_null(BerElement * ber,char ** buf)592 ber_get_stringa_null( BerElement *ber, char **buf )
593 {
594 	BerValue	bv;
595 	ber_tag_t	tag;
596 
597 	assert( buf != NULL );
598 
599 	tag = ber_get_stringbv_null( ber, &bv, LBER_BV_ALLOC | LBER_BV_STRING );
600 	*buf = bv.bv_val;
601 
602 	return tag;
603 }
604 
605 ber_tag_t
ber_get_stringal(BerElement * ber,struct berval ** bv)606 ber_get_stringal( BerElement *ber, struct berval **bv )
607 {
608 	ber_tag_t	tag;
609 
610 	assert( ber != NULL );
611 	assert( bv != NULL );
612 
613 	*bv = (struct berval *) ber_memalloc_x( sizeof(struct berval),
614 		ber->ber_memctx );
615 	if ( *bv == NULL ) {
616 		return LBER_DEFAULT;
617 	}
618 
619 	tag = ber_get_stringbv( ber, *bv, LBER_BV_ALLOC );
620 	if ( tag == LBER_DEFAULT ) {
621 		ber_memfree_x( *bv, ber->ber_memctx );
622 		*bv = NULL;
623 	}
624 	return tag;
625 }
626 
627 ber_tag_t
ber_get_bitstringa(BerElement * ber,char ** buf,ber_len_t * blen)628 ber_get_bitstringa(
629 	BerElement *ber,
630 	char **buf,
631 	ber_len_t *blen )
632 {
633 	ber_tag_t	tag;
634 	struct berval	data;
635 	unsigned char	unusedbits;
636 
637 	assert( buf != NULL );
638 	assert( blen != NULL );
639 
640 	if ( (tag = ber_skip_element( ber, &data )) == LBER_DEFAULT ) {
641 		goto fail;
642 	}
643 
644 	if ( --data.bv_len > (ber_len_t)-1 / 8 ) {
645 		goto fail;
646 	}
647 	unusedbits = *(unsigned char *) data.bv_val++;
648 	if ( unusedbits > 7 ) {
649 		goto fail;
650 	}
651 
652 	if ( memchr( data.bv_val, 0, data.bv_len )) {
653 		goto fail;
654 	}
655 
656 	*buf = (char *) ber_memalloc_x( data.bv_len, ber->ber_memctx );
657 	if ( *buf == NULL ) {
658 		return LBER_DEFAULT;
659 	}
660 	memcpy( *buf, data.bv_val, data.bv_len );
661 
662 	*blen = data.bv_len * 8 - unusedbits;
663 	return tag;
664 
665  fail:
666 	*buf = NULL;
667 	return LBER_DEFAULT;
668 }
669 
670 ber_tag_t
ber_get_null(BerElement * ber)671 ber_get_null( BerElement *ber )
672 {
673 	ber_len_t	len;
674 	ber_tag_t	tag = ber_skip_tag( ber, &len );
675 
676 	return( len == 0 ? tag : LBER_DEFAULT );
677 }
678 
679 ber_tag_t
ber_get_boolean(BerElement * ber,ber_int_t * boolval)680 ber_get_boolean(
681 	BerElement *ber,
682 	ber_int_t *boolval )
683 {
684 	return ber_get_int( ber, boolval );
685 }
686 
687 ber_tag_t
ber_first_element(BerElement * ber,ber_len_t * len,char ** last)688 ber_first_element(
689 	BerElement *ber,
690 	ber_len_t *len,
691 	char **last )
692 {
693 	assert( last != NULL );
694 
695 	/* skip the sequence header, use the len to mark where to stop */
696 	if ( ber_skip_tag( ber, len ) == LBER_DEFAULT ) {
697 		*last = NULL;
698 		return LBER_DEFAULT;
699 	}
700 
701 	*last = ber->ber_ptr + *len;
702 
703 	if ( *len == 0 ) {
704 		return LBER_DEFAULT;
705 	}
706 
707 	return ber_peek_tag( ber, len );
708 }
709 
710 ber_tag_t
ber_next_element(BerElement * ber,ber_len_t * len,LDAP_CONST char * last)711 ber_next_element(
712 	BerElement *ber,
713 	ber_len_t *len,
714 	LDAP_CONST char *last )
715 {
716 	assert( ber != NULL );
717 	assert( last != NULL );
718 	assert( LBER_VALID( ber ) );
719 
720 	if ( ber->ber_ptr >= last ) {
721 		return LBER_DEFAULT;
722 	}
723 
724 	return ber_peek_tag( ber, len );
725 }
726 
727 /* VARARGS */
728 ber_tag_t
ber_scanf(BerElement * ber,LDAP_CONST char * fmt,...)729 ber_scanf ( BerElement *ber,
730 	LDAP_CONST char *fmt,
731 	... )
732 {
733 	va_list		ap;
734 	LDAP_CONST char		*fmt_reset;
735 	char		*s, **ss, ***sss;
736 	struct berval	data, *bval, **bvp, ***bvpp;
737 	ber_int_t	*i;
738 	ber_len_t	*l;
739 	ber_tag_t	*t;
740 	ber_tag_t	rc;
741 	ber_len_t	len;
742 
743 	va_start( ap, fmt );
744 
745 	assert( ber != NULL );
746 	assert( fmt != NULL );
747 	assert( LBER_VALID( ber ) );
748 
749 	fmt_reset = fmt;
750 
751 	if ( ber->ber_debug & (LDAP_DEBUG_TRACE|LDAP_DEBUG_BER)) {
752 		ber_log_printf( LDAP_DEBUG_TRACE, ber->ber_debug,
753 			"ber_scanf fmt (%s) ber:\n", fmt );
754 		ber_log_dump( LDAP_DEBUG_BER, ber->ber_debug, ber, 1 );
755 	}
756 
757 	for ( rc = 0; *fmt && rc != LBER_DEFAULT; fmt++ ) {
758 		/* When this is modified, remember to update
759 		 * the error-cleanup code below accordingly. */
760 		switch ( *fmt ) {
761 		case '!': { /* Hook */
762 				BERDecodeCallback *f;
763 				void *p;
764 
765 				f = va_arg( ap, BERDecodeCallback * );
766 				p = va_arg( ap, void * );
767 
768 				rc = (*f)( ber, p, 0 );
769 			} break;
770 
771 		case 'a':	/* octet string - allocate storage as needed */
772 			ss = va_arg( ap, char ** );
773 			rc = ber_get_stringa( ber, ss );
774 			break;
775 
776 		case 'A':	/* octet string - allocate storage as needed,
777 				 * but return NULL if len == 0 */
778 			ss = va_arg( ap, char ** );
779 			rc = ber_get_stringa_null( ber, ss );
780 			break;
781 
782 		case 'b':	/* boolean */
783 			i = va_arg( ap, ber_int_t * );
784 			rc = ber_get_boolean( ber, i );
785 			break;
786 
787 		case 'B':	/* bit string - allocate storage as needed */
788 			ss = va_arg( ap, char ** );
789 			l = va_arg( ap, ber_len_t * ); /* for length, in bits */
790 			rc = ber_get_bitstringa( ber, ss, l );
791 			break;
792 
793 		case 'e':	/* enumerated */
794 		case 'i':	/* integer */
795 			i = va_arg( ap, ber_int_t * );
796 			rc = ber_get_int( ber, i );
797 			break;
798 
799 		case 'l':	/* length of next item */
800 			l = va_arg( ap, ber_len_t * );
801 			rc = ber_peek_tag( ber, l );
802 			break;
803 
804 		case 'm':	/* octet string in berval, in-place */
805 			bval = va_arg( ap, struct berval * );
806 			rc = ber_get_stringbv( ber, bval, 0 );
807 			break;
808 
809 		case 'M':	/* bvoffarray - must include address of
810 				 * a record len, and record offset.
811 				 * number of records will be returned thru
812 				 * len ptr on finish. parsed in-place.
813 				 */
814 		{
815 			bgbvr cookie = { BvOff, 0 };
816 			bvp = va_arg( ap, struct berval ** );
817 			l = va_arg( ap, ber_len_t * );
818 			cookie.siz = *l;
819 			cookie.off = va_arg( ap, ber_len_t );
820 			rc = ber_get_stringbvl( ber, &cookie );
821 			*bvp = cookie.result;
822 			*l = cookie.siz;
823 			break;
824 		}
825 
826 		case 'n':	/* null */
827 			rc = ber_get_null( ber );
828 			break;
829 
830 		case 'o':	/* octet string in a supplied berval */
831 			bval = va_arg( ap, struct berval * );
832 			rc = ber_get_stringbv( ber, bval, LBER_BV_ALLOC );
833 			break;
834 
835 		case 'O':	/* octet string - allocate & include length */
836 			bvp = va_arg( ap, struct berval ** );
837 			rc = ber_get_stringal( ber, bvp );
838 			break;
839 
840 		case 's':	/* octet string - in a buffer */
841 			s = va_arg( ap, char * );
842 			l = va_arg( ap, ber_len_t * );
843 			rc = ber_get_stringb( ber, s, l );
844 			break;
845 
846 		case 't':	/* tag of next item */
847 			t = va_arg( ap, ber_tag_t * );
848 			*t = rc = ber_peek_tag( ber, &len );
849 			break;
850 
851 		case 'T':	/* skip tag of next item */
852 			t = va_arg( ap, ber_tag_t * );
853 			*t = rc = ber_skip_tag( ber, &len );
854 			break;
855 
856 		case 'v':	/* sequence of strings */
857 		{
858 			bgbvr cookie = {
859 				ChArray, LBER_BV_ALLOC | LBER_BV_STRING, sizeof( char * )
860 			};
861 			rc = ber_get_stringbvl( ber, &cookie );
862 			*(va_arg( ap, char *** )) = cookie.result;
863 			break;
864 		}
865 
866 		case 'V':	/* sequence of strings + lengths */
867 		{
868 			bgbvr cookie = {
869 				BvVec, LBER_BV_ALLOC, sizeof( struct berval * )
870 			};
871 			rc = ber_get_stringbvl( ber, &cookie );
872 			*(va_arg( ap, struct berval *** )) = cookie.result;
873 			break;
874 		}
875 
876 		case 'W':	/* bvarray */
877 		{
878 			bgbvr cookie = {
879 				BvArray, LBER_BV_ALLOC, sizeof( struct berval )
880 			};
881 			rc = ber_get_stringbvl( ber, &cookie );
882 			*(va_arg( ap, struct berval ** )) = cookie.result;
883 			break;
884 		}
885 
886 		case 'x':	/* skip the next element - whatever it is */
887 			rc = ber_skip_element( ber, &data );
888 			break;
889 
890 		case '{':	/* begin sequence */
891 		case '[':	/* begin set */
892 			switch ( fmt[1] ) {
893 			case 'v': case 'V': case 'W': case 'M':
894 				break;
895 			default:
896 				rc = ber_skip_tag( ber, &len );
897 				break;
898 			}
899 			break;
900 
901 		case '}':	/* end sequence */
902 		case ']':	/* end set */
903 			break;
904 
905 		default:
906 			if( ber->ber_debug ) {
907 				ber_log_printf( LDAP_DEBUG_ANY, ber->ber_debug,
908 					"ber_scanf: unknown fmt %c\n", *fmt );
909 			}
910 			rc = LBER_DEFAULT;
911 			break;
912 		}
913 	}
914 
915 	va_end( ap );
916 
917 	if ( rc == LBER_DEFAULT ) {
918 		/*
919 		 * Error.  Reclaim malloced memory that was given to the caller.
920 		 * Set allocated pointers to NULL, "data length" outvalues to 0.
921 		 */
922 		va_start( ap, fmt );
923 
924 		for ( ; fmt_reset < fmt; fmt_reset++ ) {
925 		switch ( *fmt_reset ) {
926 		case '!': { /* Hook */
927 				BERDecodeCallback *f;
928 				void *p;
929 
930 				f = va_arg( ap, BERDecodeCallback * );
931 				p = va_arg( ap, void * );
932 
933 				(void) (*f)( ber, p, 1 );
934 			} break;
935 
936 		case 'a':	/* octet string - allocate storage as needed */
937 		case 'A':
938 			ss = va_arg( ap, char ** );
939 			ber_memfree_x( *ss, ber->ber_memctx );
940 			*ss = NULL;
941 			break;
942 
943 		case 'b':	/* boolean */
944 		case 'e':	/* enumerated */
945 		case 'i':	/* integer */
946 			(void) va_arg( ap, ber_int_t * );
947 			break;
948 
949 		case 'l':	/* length of next item */
950 			*(va_arg( ap, ber_len_t * )) = 0;
951 			break;
952 
953 		case 'm':	/* berval in-place */
954 			bval = va_arg( ap, struct berval * );
955 			BER_BVZERO( bval );
956 			break;
957 
958 		case 'M':	/* BVoff array in-place */
959 			bvp = va_arg( ap, struct berval ** );
960 			ber_memfree_x( *bvp, ber->ber_memctx );
961 			*bvp = NULL;
962 			*(va_arg( ap, ber_len_t * )) = 0;
963 			(void) va_arg( ap, ber_len_t );
964 			break;
965 
966 		case 'o':	/* octet string in a supplied berval */
967 			bval = va_arg( ap, struct berval * );
968 			ber_memfree_x( bval->bv_val, ber->ber_memctx );
969 			BER_BVZERO( bval );
970 			break;
971 
972 		case 'O':	/* octet string - allocate & include length */
973 			bvp = va_arg( ap, struct berval ** );
974 			ber_bvfree_x( *bvp, ber->ber_memctx );
975 			*bvp = NULL;
976 			break;
977 
978 		case 's':	/* octet string - in a buffer */
979 			(void) va_arg( ap, char * );
980 			*(va_arg( ap, ber_len_t * )) = 0;
981 			break;
982 
983 		case 't':	/* tag of next item */
984 		case 'T':	/* skip tag of next item */
985 			(void) va_arg( ap, ber_tag_t * );
986 			break;
987 
988 		case 'B':	/* bit string - allocate storage as needed */
989 			ss = va_arg( ap, char ** );
990 			ber_memfree_x( *ss, ber->ber_memctx );
991 			*ss = NULL;
992 			*(va_arg( ap, ber_len_t * )) = 0; /* for length, in bits */
993 			break;
994 
995 		case 'v':	/* sequence of strings */
996 			sss = va_arg( ap, char *** );
997 			ber_memvfree_x( (void **) *sss, ber->ber_memctx );
998 			*sss = NULL;
999 			break;
1000 
1001 		case 'V':	/* sequence of strings + lengths */
1002 			bvpp = va_arg( ap, struct berval *** );
1003 			ber_bvecfree_x( *bvpp, ber->ber_memctx );
1004 			*bvpp = NULL;
1005 			break;
1006 
1007 		case 'W':	/* BerVarray */
1008 			bvp = va_arg( ap, struct berval ** );
1009 			ber_bvarray_free_x( *bvp, ber->ber_memctx );
1010 			*bvp = NULL;
1011 			break;
1012 
1013 		case 'n':	/* null */
1014 		case 'x':	/* skip the next element - whatever it is */
1015 		case '{':	/* begin sequence */
1016 		case '[':	/* begin set */
1017 		case '}':	/* end sequence */
1018 		case ']':	/* end set */
1019 			break;
1020 
1021 		default:
1022 			/* format should be good */
1023 			assert( 0 );
1024 		}
1025 		}
1026 
1027 		va_end( ap );
1028 	}
1029 
1030 	return rc;
1031 }
1032