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      1 /*	$NetBSD: decode.c,v 1.4 2025/09/05 21:16:20 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 1998-2024 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 1.4 2025/09/05 21:16:20 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
     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
     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
    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
    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
    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
    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
    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
    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
    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
    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
    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
    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
    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
    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
    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
    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
    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
    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
    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
    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
    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
    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
    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
    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