xref: /onnv-gate/usr/src/lib/libldap4/ber/decode.c (revision 0:68f95e015346)
1 /*
2  * Copyright 2004 Sun Microsystems, Inc.  All rights reserved.
3  * Use is subject to license terms.
4  */
5 
6 #pragma ident	"%Z%%M%	%I%	%E% SMI"
7 
8 /* decode.c - ber input decoding routines */
9 /*
10  * Copyright (c) 1990 Regents of the University of Michigan.
11  * All rights reserved.
12  *
13  * Redistribution and use in source and binary forms are permitted
14  * provided that this notice is preserved and that due credit is given
15  * to the University of Michigan at Ann Arbor. The name of the University
16  * may not be used to endorse or promote products derived from this
17  * software without specific prior written permission. This software
18  * is provided ``as is'' without express or implied warranty.
19  */
20 
21 #include <stdio.h>
22 #ifdef MACOS
23 #include <stdlib.h>
24 #include <stdarg.h>
25 #include "macos.h"
26 #else /* MACOS */
27 #if defined(NeXT) || defined(VMS)
28 #include <stdlib.h>
29 #else /* next || vms */
30 #include <malloc.h>
31 #endif /* next || vms */
32 #if defined(BC31) || defined(_WIN32) || defined(__sun)
33 #include <stdarg.h>
34 #else /* BC31 || _WIN32 */
35 #include <varargs.h>
36 #endif /* BC31 || _WIN32 */
37 #include <sys/types.h>
38 #include <sys/socket.h>
39 #include <netinet/in.h>
40 #ifdef PCNFS
41 #include <tklib.h>
42 #endif /* PCNFS */
43 #endif /* MACOS */
44 
45 #if defined( DOS ) || defined( _WIN32 )
46 #include "msdos.h"
47 #endif /* DOS */
48 
49 #include <string.h>
50 #include "lber.h"
51 #include "ldap.h"
52 #include "ldap-private.h"
53 #include "ldap-int.h"
54 
55 #ifdef LDAP_DEBUG
56 int	lber_debug;
57 #endif
58 
59 #ifdef NEEDPROTOS
60 static int ber_getnint( BerElement *ber, int *num, int len );
61 #endif /* NEEDPROTOS */
62 
63 
64 /* return the tag - LBER_DEFAULT returned means trouble */
65 unsigned int
ber_get_tag(BerElement * ber)66 ber_get_tag( BerElement *ber )
67 {
68 	unsigned char	xbyte;
69 	unsigned int	tag;
70 	char		*tagp;
71 	int		i;
72 
73 	if ( ber_read( ber, (char *) &xbyte, 1 ) != 1 )
74 		return( LBER_DEFAULT );
75 
76 	if ( (xbyte & LBER_BIG_TAG_MASK) != LBER_BIG_TAG_MASK )
77 		return( (unsigned int) xbyte );
78 
79 	tagp = (char *) &tag;
80 	tagp[0] = xbyte;
81 	for ( i = 1; i < sizeof(int); i++ ) {
82 		if ( ber_read( ber, (char *) &xbyte, 1 ) != 1 )
83 			return( LBER_DEFAULT );
84 
85 		tagp[i] = xbyte;
86 
87 		if ( ! (xbyte & LBER_MORE_TAG_MASK) )
88 			break;
89 	}
90 
91 	/* tag too big! */
92 	if ( i == sizeof(int) )
93 		return( LBER_DEFAULT );
94 
95 	/* want leading, not trailing 0's */
96 	return( tag >> (sizeof(int) - i - 1) );
97 }
98 
99 unsigned int
ber_skip_tag(BerElement * ber,unsigned int * len)100 ber_skip_tag( BerElement *ber, unsigned int *len )
101 {
102 	unsigned int	tag;
103 	unsigned char	lc;
104 	int		noctets, diff;
105 	unsigned int	netlen;
106 
107 	/*
108 	 * Any ber element looks like this: tag length contents.
109 	 * Assuming everything's ok, we return the tag byte (we
110 	 * can assume a single byte), and return the length in len.
111 	 *
112 	 * Assumptions:
113 	 *	1) definite lengths
114 	 *	2) primitive encodings used whenever possible
115 	 */
116 
117 	/*
118 	 * First, we read the tag.
119 	 */
120 
121 	if ( (tag = ber_get_tag( ber )) == LBER_DEFAULT )
122 		return( LBER_DEFAULT );
123 
124 	/*
125 	 * Next, read the length.  The first byte contains the length of
126 	 * the length.  If bit 8 is set, the length is the int form,
127 	 * otherwise it's the short form.  We don't allow a length that's
128 	 * greater than what we can hold in an unsigned int.
129 	 */
130 
131 	*len = netlen = 0;
132 	if ( ber_read( ber, (char *) &lc, 1 ) != 1 )
133 		return( LBER_DEFAULT );
134 	if ( lc & 0x80 ) {
135 		noctets = (lc & 0x7f);
136 		if ( noctets > sizeof(unsigned int) )
137 			return( LBER_DEFAULT );
138 		diff = (int)sizeof(unsigned int) - noctets;
139 		if ( ber_read( ber, (char *) &netlen + diff, noctets )
140 		    != noctets )
141 			return( LBER_DEFAULT );
142 		*len = LBER_NTOHL( netlen );
143 	} else {
144 		*len = lc;
145 	}
146 
147 	return( tag );
148 }
149 
150 unsigned int
ber_peek_tag(BerElement * ber,unsigned int * len)151 ber_peek_tag( BerElement *ber, unsigned int *len )
152 {
153 	char		*save;
154 	unsigned int	tag;
155 
156 	save = ber->ber_ptr;
157 	tag = ber_skip_tag( ber, len );
158 	ber->ber_ptr = save;
159 
160 	return( tag );
161 }
162 
163 static int
ber_getnint(BerElement * ber,int * num,int len)164 ber_getnint( BerElement *ber, int *num, int len )
165 {	/* New patch much cleaner, from David Wilson, Isode. Old code not kept*/
166  	int	i;
167  	unsigned char buffer[sizeof(int)];
168  	int	value;
169 
170   	/*
171   	 * The tag and length have already been stripped off.  We should
172   	 * be sitting right before len bytes of 2's complement integer,
173  	 * ready to be read straight into an int.
174   	 */
175 
176   	if ( len > sizeof(int) )
177   		return( -1 );
178 
179  	if ( ber_read( ber, (char *) buffer, len ) != len )
180   		return( -1 );
181 
182  	/* This sets the required sign extension */
183  	value = 0x80 & buffer[0] ? (-1) : 0;
184 
185  	for ( i = 0; i < len; i++ )
186  	    value = (value << 8) | buffer[i];
187 
188 	*num = value;
189 
190   	return( len );
191 }
192 
193 unsigned int
ber_get_int(BerElement * ber,int * num)194 ber_get_int( BerElement *ber, int *num )
195 {
196 	unsigned int	tag, len;
197 
198 	if ( (tag = ber_skip_tag( ber, &len )) == LBER_DEFAULT )
199 		return( LBER_DEFAULT );
200 
201 	if ( ber_getnint( ber, num, (int)len ) != len )
202 		return( LBER_DEFAULT );
203 	else
204 		return( tag );
205 }
206 
207 unsigned int
ber_get_stringb(BerElement * ber,char * buf,unsigned int * len)208 ber_get_stringb( BerElement *ber, char *buf, unsigned int *len )
209 {
210 	unsigned int	datalen, tag;
211 #ifdef STR_TRANSLATION
212 	char		*transbuf;
213 #endif /* STR_TRANSLATION */
214 
215 	if ( (tag = ber_skip_tag( ber, &datalen )) == LBER_DEFAULT )
216 		return( LBER_DEFAULT );
217 	if ( datalen > (*len - 1) )
218 		return( LBER_DEFAULT );
219 
220 	if ( ber_read( ber, buf, datalen ) != datalen )
221 		return( LBER_DEFAULT );
222 
223 	buf[datalen] = '\0';
224 
225 #ifdef STR_TRANSLATION
226 	if ( datalen > 0 && ( ber->ber_options & LBER_TRANSLATE_STRINGS ) != 0
227 	    && ber->ber_decode_translate_proc != NULL ) {
228 		transbuf = buf;
229 		++datalen;
230 		if ( (*(ber->ber_decode_translate_proc))( &transbuf, &datalen,
231 		    0 ) != 0 ) {
232 			return( LBER_DEFAULT );
233 		}
234 		if ( datalen > *len ) {
235 			free( transbuf );
236 			return( LBER_DEFAULT );
237 		}
238 		(void) SAFEMEMCPY( buf, transbuf, datalen );
239 		free( transbuf );
240 		--datalen;
241 	}
242 #endif /* STR_TRANSLATION */
243 
244 	*len = datalen;
245 	return( tag );
246 }
247 
248 unsigned int
ber_get_stringa(BerElement * ber,char ** buf)249 ber_get_stringa( BerElement *ber, char **buf )
250 {
251 	unsigned int	datalen, tag;
252 
253 	if ( (tag = ber_skip_tag( ber, &datalen )) == LBER_DEFAULT )
254 		return( LBER_DEFAULT );
255 
256 	if ( (*buf = (char *) malloc( (size_t)datalen + 1 )) == NULL )
257 		return( LBER_DEFAULT );
258 
259 	if ( ber_read( ber, *buf, datalen ) != datalen )
260 		return( LBER_DEFAULT );
261 	(*buf)[datalen] = '\0';
262 
263 #ifdef STR_TRANSLATION
264 	if ( datalen > 0 && ( ber->ber_options & LBER_TRANSLATE_STRINGS ) != 0
265 	    && ber->ber_decode_translate_proc != NULL ) {
266 		++datalen;
267 		if ( (*(ber->ber_decode_translate_proc))( buf, &datalen, 1 )
268 		    != 0 ) {
269 			free( *buf );
270 			return( LBER_DEFAULT );
271 		}
272 	}
273 #endif /* STR_TRANSLATION */
274 
275 	return( tag );
276 }
277 
278 unsigned int
ber_get_stringal(BerElement * ber,struct berval ** bv)279 ber_get_stringal( BerElement *ber, struct berval **bv )
280 {
281 	unsigned int	len, tag;
282 
283 	if ( (*bv = (struct berval *) malloc( sizeof(struct berval) )) == NULL )
284 		return( LBER_DEFAULT );
285 
286 	if ( (tag = ber_skip_tag( ber, &len )) == LBER_DEFAULT )
287 		return( LBER_DEFAULT );
288 
289 	if ( ((*bv)->bv_val = (char *) malloc( (size_t)len + 1 )) == NULL )
290 		return( LBER_DEFAULT );
291 
292 	if ( ber_read( ber, (*bv)->bv_val, len ) != len )
293 		return( LBER_DEFAULT );
294 	((*bv)->bv_val)[len] = '\0';
295 	(*bv)->bv_len = len;
296 
297 #ifdef STR_TRANSLATION
298 	if ( len > 0 && ( ber->ber_options & LBER_TRANSLATE_STRINGS ) != 0
299 	    && ber->ber_decode_translate_proc != NULL ) {
300 		++len;
301 		if ( (*(ber->ber_decode_translate_proc))( &((*bv)->bv_val),
302 		    &len, 1 ) != 0 ) {
303 			free( (*bv)->bv_val );
304 			return( LBER_DEFAULT );
305 		}
306 		(*bv)->bv_len = len - 1;
307 	}
308 #endif /* STR_TRANSLATION */
309 
310 	return( tag );
311 }
312 
313 unsigned int
ber_get_bitstringa(BerElement * ber,char ** buf,unsigned int * blen)314 ber_get_bitstringa( BerElement *ber, char **buf, unsigned int *blen )
315 {
316 	unsigned int	datalen, tag;
317 	unsigned char	unusedbits;
318 
319 	if ( (tag = ber_skip_tag( ber, &datalen )) == LBER_DEFAULT )
320 		return( LBER_DEFAULT );
321 	--datalen;
322 
323 	if ( (*buf = (char *) malloc( (size_t)datalen )) == NULL )
324 		return( LBER_DEFAULT );
325 
326 	if ( ber_read( ber, (char *)&unusedbits, 1 ) != 1 )
327 		return( LBER_DEFAULT );
328 
329 	if ( ber_read( ber, *buf, datalen ) != datalen )
330 		return( LBER_DEFAULT );
331 
332 	*blen = datalen * 8 - unusedbits;
333 	return( tag );
334 }
335 
336 unsigned int
ber_get_null(BerElement * ber)337 ber_get_null( BerElement *ber )
338 {
339 	unsigned int	len, tag;
340 
341 	if ( (tag = ber_skip_tag( ber, &len )) == LBER_DEFAULT )
342 		return( LBER_DEFAULT );
343 
344 	if ( len != 0 )
345 		return( LBER_DEFAULT );
346 
347 	return( tag );
348 }
349 
350 unsigned int
ber_get_boolean(BerElement * ber,int * boolval)351 ber_get_boolean( BerElement *ber, int *boolval )
352 {
353 	int	longbool;
354 	int	rc;
355 
356 	rc = ber_get_int( ber, &longbool );
357 	*boolval = longbool;
358 
359 	return( rc );
360 }
361 
362 unsigned int
ber_first_element(BerElement * ber,unsigned int * len,char ** last)363 ber_first_element( BerElement *ber, unsigned int *len, char **last )
364 {
365 	/* skip the sequence header, use the len to mark where to stop */
366 	if ( ber_skip_tag( ber, len ) == LBER_DEFAULT ) {
367 		return( LBER_DEFAULT );
368 	}
369 
370 	*last = ber->ber_ptr + *len;
371 
372 	if ( *last == ber->ber_ptr ) {
373 		return( LBER_DEFAULT );
374 	}
375 
376 	return( ber_peek_tag( ber, len ) );
377 }
378 
379 unsigned int
ber_next_element(BerElement * ber,unsigned int * len,char * last)380 ber_next_element( BerElement *ber, unsigned int *len, char *last )
381 {
382 	if ( ber->ber_ptr == last ) {
383 		return( LBER_DEFAULT );
384 	}
385 
386 	return( ber_peek_tag( ber, len ) );
387 }
388 
389 /* VARARGS */
390 unsigned int
ber_scanf(BerElement * ber,char * fmt,...)391 ber_scanf(
392 #if defined(MACOS) || defined(BC31) || defined(_WIN32) || defined(__sun)
393 	BerElement *ber, char *fmt, ... )
394 #else
395 	va_alist )
396 va_dcl
397 #endif
398 {
399 	va_list		ap;
400 #if !defined(MACOS) && !defined(BC31) && !defined(_WIN32) && !defined(__sun)
401 	BerElement	*ber;
402 	char		*fmt;
403 #endif
404 	char		*last;
405 	char		*s, **ss, ***sss;
406 	struct berval 	***bv, **bvp, *bval;
407 	int		*i, j;
408 	int		*l, rc, tag;
409 	unsigned int	len;
410 
411 #if defined(MACOS) || defined(BC31) || defined(_WIN32) || defined(__sun)
412 	va_start( ap, fmt );
413 #else
414 	va_start( ap );
415 	ber = va_arg( ap, BerElement * );
416 	fmt = va_arg( ap, char * );
417 #endif
418 
419 #ifdef LDAP_DEBUG
420 	if ( lber_debug & 64 ) {
421 		(void) fprintf( stderr, catgets(slapdcat, 1, 73, "ber_scanf fmt (%s) ber:\n"), fmt );
422 		ber_dump( ber, 1 );
423 	}
424 #endif
425 
426 	for ( rc = 0; *fmt && rc != LBER_DEFAULT; fmt++ ) {
427 		switch ( *fmt ) {
428 		case 'a':	/* octet string - allocate storage as needed */
429 			ss = va_arg( ap, char ** );
430 			rc = ber_get_stringa( ber, ss );
431 			break;
432 
433 		case 'b':	/* boolean */
434 			i = va_arg( ap, int * );
435 			rc = ber_get_boolean( ber, i );
436 			break;
437 
438 		case 'e':	/* enumerated */
439 		case 'i':	/* int */
440 			l = va_arg( ap, int * );
441 			rc = ber_get_int( ber, l );
442 			break;
443 
444 		case 'l':	/* length of next item */
445 			l = va_arg( ap, int * );
446 			rc = ber_peek_tag( ber, (unsigned int *)l );
447 			break;
448 
449 		case 'n':	/* null */
450 			rc = ber_get_null( ber );
451 			break;
452 
453 		case 's':	/* octet string - in a buffer */
454 			s = va_arg( ap, char * );
455 			l = va_arg( ap, int * );
456 			rc = ber_get_stringb( ber, s, (unsigned int *)l );
457 			break;
458 
459 		case 'o':	/* octet string in a supplied berval */
460 			bval = va_arg( ap, struct berval * );
461 			ber_peek_tag( ber, &bval->bv_len );
462 			rc = ber_get_stringa( ber, &bval->bv_val );
463 			break;
464 
465 		case 'O':	/* octet string - allocate & include length */
466 			bvp = va_arg( ap, struct berval ** );
467 			rc = ber_get_stringal( ber, bvp );
468 			break;
469 
470 		case 'B':	/* bit string - allocate storage as needed */
471 			ss = va_arg( ap, char ** );
472 			l = va_arg( ap, int * ); /* for length, in bits */
473 			rc = ber_get_bitstringa( ber, ss, (unsigned int *)l );
474 			break;
475 
476 		case 't':	/* tag of next item */
477 			i = va_arg( ap, int * );
478 			*i = rc = ber_peek_tag( ber, &len );
479 			break;
480 
481 		case 'T':	/* skip tag of next item */
482 			i = va_arg( ap, int * );
483 			*i = rc = ber_skip_tag( ber, &len );
484 			break;
485 
486 		case 'v':	/* sequence of strings */
487 			sss = va_arg( ap, char *** );
488 			*sss = NULL;
489 			j = 0;
490 			for ( tag = ber_first_element( ber, &len, &last );
491 			    tag != LBER_DEFAULT && rc != LBER_DEFAULT;
492 			    tag = ber_next_element( ber, &len, last ) ) {
493 				if ( *sss == NULL ) {
494 					*sss = (char **) malloc(
495 					    2 * sizeof(char *) );
496 				} else {
497 					*sss = (char **) realloc( *sss,
498 					    (j + 2) * sizeof(char *) );
499 				}
500 				rc = ber_get_stringa( ber, &((*sss)[j]) );
501 				j++;
502 			}
503 			if ( j > 0 )
504 				(*sss)[j] = NULL;
505 			break;
506 
507 		case 'V':	/* sequence of strings + lengths */
508 			bv = va_arg( ap, struct berval *** );
509 			*bv = NULL;
510 			j = 0;
511 			for ( tag = ber_first_element( ber, &len, &last );
512 			    tag != LBER_DEFAULT && rc != LBER_DEFAULT;
513 			    tag = ber_next_element( ber, &len, last ) ) {
514 				if ( *bv == NULL ) {
515 					*bv = (struct berval **) malloc(
516 					    2 * sizeof(struct berval *) );
517 				} else {
518 					*bv = (struct berval **) realloc( *bv,
519 					    (j + 2) * sizeof(struct berval *) );
520 				}
521 				rc = ber_get_stringal( ber, &((*bv)[j]) );
522 				j++;
523 			}
524 			if ( j > 0 )
525 				(*bv)[j] = NULL;
526 			break;
527 
528 		case 'x':	/* skip the next element - whatever it is */
529 			if ( (rc = ber_skip_tag( ber, &len )) == LBER_DEFAULT )
530 				break;
531 			ber->ber_ptr += len;
532 			break;
533 
534 		case '{':	/* begin sequence */
535 		case '[':	/* begin set */
536 			if ( *(fmt + 1) != 'v' && *(fmt + 1) != 'V' )
537 				rc = ber_skip_tag( ber, &len );
538 			break;
539 
540 		case '}':	/* end sequence */
541 		case ']':	/* end set */
542 			break;
543 
544 		default:
545 #ifndef NO_USERINTERFACE
546 			(void) fprintf( stderr, catgets(slapdcat, 1, 74, "unknown fmt %c\n"), *fmt );
547 #endif /* NO_USERINTERFACE */
548 			rc = (int) LBER_DEFAULT;
549 			break;
550 		}
551 	}
552 
553 	va_end( ap );
554 
555 	return( rc );
556 }
557 
558 void
ber_bvfree(struct berval * bv)559 ber_bvfree( struct berval *bv )
560 {
561 	if ( bv->bv_val != NULL )
562 		free( bv->bv_val );
563 	free( (char *) bv );
564 }
565 
566 void
ber_bvecfree(struct berval ** bv)567 ber_bvecfree( struct berval **bv )
568 {
569 	int	i;
570 
571 	for ( i = 0; bv[i] != NULL; i++ )
572 		ber_bvfree( bv[i] );
573 	free( (char *) bv );
574 }
575 
576 struct berval *
ber_bvdup(struct berval * bv)577 ber_bvdup( struct berval *bv )
578 {
579 	struct berval	*new;
580 
581 	if ( (new = (struct berval *) malloc( sizeof(struct berval) ))
582 	    == NULL ) {
583 		return( NULL );
584 	}
585 	if ( (new->bv_val = (char *) malloc( bv->bv_len + 1 )) == NULL ) {
586 		free(new);
587 		return( NULL );
588 	}
589 	SAFEMEMCPY( new->bv_val, bv->bv_val, (size_t) bv->bv_len );
590 	new->bv_val[bv->bv_len] = '\0';
591 	new->bv_len = bv->bv_len;
592 
593 	return( new );
594 }
595 
596 
597 #ifdef STR_TRANSLATION
598 void
ber_set_string_translators(BerElement * ber,BERTranslateProc encode_proc,BERTranslateProc decode_proc)599 ber_set_string_translators( BerElement *ber, BERTranslateProc encode_proc,
600 	BERTranslateProc decode_proc )
601 {
602     ber->ber_encode_translate_proc = encode_proc;
603     ber->ber_decode_translate_proc = decode_proc;
604 }
605 #endif /* STR_TRANSLATION */
606 
ber_flatten(BerElement * ber,struct berval ** bvPtr)607 int ber_flatten(BerElement *ber, struct berval **bvPtr)
608 {
609 	struct berval * bv;
610 	int len;
611 
612 	if ((ber == NULL) || (ber->ber_buf == NULL))
613 		return (-1);
614 
615 	len = ber->ber_ptr - ber->ber_buf;
616 
617 	if ((bv = (struct berval *)malloc(sizeof(struct berval))) == NULL)
618 		return (-1);
619 	if ((bv->bv_val = (char *) malloc(len + 1)) == NULL) {
620 		free(bv);
621 		return (-1);
622 	}
623 
624 	SAFEMEMCPY(bv->bv_val, ber->ber_buf, (size_t)len);
625 	bv->bv_val[len] = '\0';
626 	bv->bv_len = len;
627 
628 	*bvPtr = bv;
629 	return (0);
630 }
631