xref: /netbsd-src/external/bsd/openldap/dist/libraries/liblber/io.c (revision 466a16a118933bd295a8a104f095714fadf9cf68)
1 /* io.c - ber general i/o routines */
2 /* $OpenLDAP: pkg/ldap/libraries/liblber/io.c,v 1.111.2.8 2008/07/09 23:16:48 quanah Exp $ */
3 /* This work is part of OpenLDAP Software <http://www.openldap.org/>.
4  *
5  * Copyright 1998-2008 The OpenLDAP Foundation.
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted only as authorized by the OpenLDAP
10  * Public License.
11  *
12  * A copy of this license is available in the file LICENSE in the
13  * top-level directory of the distribution or, alternatively, at
14  * <http://www.OpenLDAP.org/license.html>.
15  */
16 /* Portions Copyright (c) 1990 Regents of the University of Michigan.
17  * All rights reserved.
18  *
19  * Redistribution and use in source and binary forms are permitted
20  * provided that this notice is preserved and that due credit is given
21  * to the University of Michigan at Ann Arbor. The name of the University
22  * may not be used to endorse or promote products derived from this
23  * software without specific prior written permission. This software
24  * is provided ``as is'' without express or implied warranty.
25  */
26 /* ACKNOWLEDGEMENTS:
27  * This work was originally developed by the University of Michigan
28  * (as part of U-MICH LDAP).
29  */
30 
31 #include "portable.h"
32 
33 #include <stdio.h>
34 
35 #include <ac/stdlib.h>
36 
37 #include <ac/ctype.h>
38 #include <ac/errno.h>
39 #include <ac/socket.h>
40 #include <ac/string.h>
41 #include <ac/unistd.h>
42 
43 #ifdef HAVE_IO_H
44 #include <io.h>
45 #endif
46 
47 #include "lber-int.h"
48 #include "ldap_log.h"
49 
50 ber_slen_t
51 ber_skip_data(
52 	BerElement *ber,
53 	ber_len_t len )
54 {
55 	ber_len_t	actuallen, nleft;
56 
57 	assert( ber != NULL );
58 
59 	assert( LBER_VALID( ber ) );
60 
61 	nleft = ber_pvt_ber_remaining( ber );
62 	actuallen = nleft < len ? nleft : len;
63 	ber->ber_ptr += actuallen;
64 	ber->ber_tag = *(unsigned char *)ber->ber_ptr;
65 
66 	return( (ber_slen_t) actuallen );
67 }
68 
69 ber_slen_t
70 ber_read(
71 	BerElement *ber,
72 	char *buf,
73 	ber_len_t len )
74 {
75 	ber_len_t	actuallen, nleft;
76 
77 	assert( ber != NULL );
78 	assert( buf != NULL );
79 
80 	assert( LBER_VALID( ber ) );
81 
82 	nleft = ber_pvt_ber_remaining( ber );
83 	actuallen = nleft < len ? nleft : len;
84 
85 	AC_MEMCPY( buf, ber->ber_ptr, actuallen );
86 
87 	ber->ber_ptr += actuallen;
88 
89 	return( (ber_slen_t) actuallen );
90 }
91 
92 ber_slen_t
93 ber_write(
94 	BerElement *ber,
95 	LDAP_CONST char *buf,
96 	ber_len_t len,
97 	int nosos )
98 {
99 	assert( ber != NULL );
100 	assert( buf != NULL );
101 
102 	assert( LBER_VALID( ber ) );
103 
104 	if ( nosos || ber->ber_sos == NULL ) {
105 		if ( ber->ber_ptr + len > ber->ber_end ) {
106 			if ( ber_realloc( ber, len ) != 0 ) return( -1 );
107 		}
108 		AC_MEMCPY( ber->ber_ptr, buf, (size_t)len );
109 		ber->ber_ptr += len;
110 		return( (ber_slen_t) len );
111 
112 	} else {
113 		if ( ber->ber_sos->sos_ptr + len > ber->ber_end ) {
114 			if ( ber_realloc( ber, len ) != 0 ) return( -1 );
115 		}
116 		AC_MEMCPY( ber->ber_sos->sos_ptr, buf, (size_t)len );
117 		ber->ber_sos->sos_ptr += len;
118 		ber->ber_sos->sos_clen += len;
119 		return( (ber_slen_t) len );
120 	}
121 }
122 
123 int
124 ber_realloc( BerElement *ber, ber_len_t len )
125 {
126 	ber_len_t	total;
127 	Seqorset	*s;
128 	long		off;
129 	char		*oldbuf;
130 
131 	assert( ber != NULL );
132 	assert( len > 0 );
133 	assert( LBER_VALID( ber ) );
134 
135 	total = ber_pvt_ber_total( ber );
136 
137 #define LBER_EXBUFSIZ	4060 /* a few words less than 2^N for binary buddy */
138 #if defined( LBER_EXBUFSIZ ) && LBER_EXBUFSIZ > 0
139 # ifndef notdef
140 	/* don't realloc by small amounts */
141 	total += len < LBER_EXBUFSIZ ? LBER_EXBUFSIZ : len;
142 # else
143 	{	/* not sure what value this adds */
144 		ber_len_t have = (total + (LBER_EXBUFSIZE - 1)) / LBER_EXBUFSIZ;
145 		ber_len_t need = (len + (LBER_EXBUFSIZ - 1)) / LBER_EXBUFSIZ;
146 		total = ( have + need ) * LBER_EXBUFSIZ;
147 	}
148 # endif
149 #else
150 	total += len;	/* realloc just what's needed */
151 #endif
152 
153 	oldbuf = ber->ber_buf;
154 
155 	ber->ber_buf = (char *) ber_memrealloc_x( oldbuf, total, ber->ber_memctx );
156 
157 	if ( ber->ber_buf == NULL ) {
158 		ber->ber_buf = oldbuf;
159 		return( -1 );
160 	}
161 
162 	ber->ber_end = ber->ber_buf + total;
163 
164 	/*
165 	 * If the stinking thing was moved, we need to go through and
166 	 * reset all the sos and ber pointers.	Offsets would've been
167 	 * a better idea... oh well.
168 	 */
169 
170 	if ( ber->ber_buf != oldbuf ) {
171 		ber->ber_ptr = ber->ber_buf + (ber->ber_ptr - oldbuf);
172 
173 		for ( s = ber->ber_sos; s != NULL; s = s->sos_next ) {
174 			off = s->sos_first - oldbuf;
175 			s->sos_first = ber->ber_buf + off;
176 
177 			off = s->sos_ptr - oldbuf;
178 			s->sos_ptr = ber->ber_buf + off;
179 		}
180 	}
181 
182 	return( 0 );
183 }
184 
185 void
186 ber_free_buf( BerElement *ber )
187 {
188 	Seqorset *s, *next;
189 
190 	assert( LBER_VALID( ber ) );
191 
192 	if ( ber->ber_buf) ber_memfree_x( ber->ber_buf, ber->ber_memctx );
193 
194 	for( s = ber->ber_sos ; s != NULL ; s = next ) {
195 		next = s->sos_next;
196 		ber_memfree_x( s, ber->ber_memctx );
197 	}
198 
199 	ber->ber_buf = NULL;
200 	ber->ber_sos = NULL;
201 	ber->ber_valid = LBER_UNINITIALIZED;
202 }
203 
204 void
205 ber_free( BerElement *ber, int freebuf )
206 {
207 	if( ber == NULL ) {
208 		LDAP_MEMORY_DEBUG_ASSERT( ber != NULL );
209 		return;
210 	}
211 
212 	if( freebuf ) ber_free_buf( ber );
213 
214 	ber_memfree_x( (char *) ber, ber->ber_memctx );
215 }
216 
217 int
218 ber_flush( Sockbuf *sb, BerElement *ber, int freeit )
219 {
220 	return ber_flush2( sb, ber,
221 		freeit ? LBER_FLUSH_FREE_ON_SUCCESS
222 			: LBER_FLUSH_FREE_NEVER );
223 }
224 
225 int
226 ber_flush2( Sockbuf *sb, BerElement *ber, int freeit )
227 {
228 	ber_len_t	towrite;
229 	ber_slen_t	rc;
230 
231 	assert( sb != NULL );
232 	assert( ber != NULL );
233 
234 	assert( SOCKBUF_VALID( sb ) );
235 	assert( LBER_VALID( ber ) );
236 
237 	if ( ber->ber_rwptr == NULL ) {
238 		ber->ber_rwptr = ber->ber_buf;
239 	}
240 	towrite = ber->ber_ptr - ber->ber_rwptr;
241 
242 	if ( sb->sb_debug ) {
243 		ber_log_printf( LDAP_DEBUG_TRACE, sb->sb_debug,
244 			"ber_flush2: %ld bytes to sd %ld%s\n",
245 			towrite, (long) sb->sb_fd,
246 			ber->ber_rwptr != ber->ber_buf ?  " (re-flush)" : "" );
247 		ber_log_bprint( LDAP_DEBUG_PACKETS, sb->sb_debug,
248 			ber->ber_rwptr, towrite );
249 	}
250 
251 	while ( towrite > 0 ) {
252 #ifdef LBER_TRICKLE
253 		sleep(1);
254 		rc = ber_int_sb_write( sb, ber->ber_rwptr, 1 );
255 #else
256 		rc = ber_int_sb_write( sb, ber->ber_rwptr, towrite );
257 #endif
258 		if ( rc <= 0 ) {
259 			if ( freeit & LBER_FLUSH_FREE_ON_ERROR ) ber_free( ber, 1 );
260 			return -1;
261 		}
262 		towrite -= rc;
263 		ber->ber_rwptr += rc;
264 	}
265 
266 	if ( freeit & LBER_FLUSH_FREE_ON_SUCCESS ) ber_free( ber, 1 );
267 
268 	return 0;
269 }
270 
271 BerElement *
272 ber_alloc_t( int options )
273 {
274 	BerElement	*ber;
275 
276 	ber = (BerElement *) LBER_CALLOC( 1, sizeof(BerElement) );
277 
278 	if ( ber == NULL ) {
279 		return NULL;
280 	}
281 
282 	ber->ber_valid = LBER_VALID_BERELEMENT;
283 	ber->ber_tag = LBER_DEFAULT;
284 	ber->ber_options = options;
285 	ber->ber_debug = ber_int_debug;
286 
287 	assert( LBER_VALID( ber ) );
288 	return ber;
289 }
290 
291 BerElement *
292 ber_alloc( void )	/* deprecated */
293 {
294 	return ber_alloc_t( 0 );
295 }
296 
297 BerElement *
298 der_alloc( void )	/* deprecated */
299 {
300 	return ber_alloc_t( LBER_USE_DER );
301 }
302 
303 BerElement *
304 ber_dup( BerElement *ber )
305 {
306 	BerElement	*new;
307 
308 	assert( ber != NULL );
309 	assert( LBER_VALID( ber ) );
310 
311 	if ( (new = ber_alloc_t( ber->ber_options )) == NULL ) {
312 		return NULL;
313 	}
314 
315 	*new = *ber;
316 
317 	assert( LBER_VALID( new ) );
318 	return( new );
319 }
320 
321 
322 void
323 ber_init2( BerElement *ber, struct berval *bv, int options )
324 {
325 	assert( ber != NULL );
326 
327 	(void) memset( (char *)ber, '\0', sizeof( BerElement ));
328 	ber->ber_valid = LBER_VALID_BERELEMENT;
329 	ber->ber_tag = LBER_DEFAULT;
330 	ber->ber_options = (char) options;
331 	ber->ber_debug = ber_int_debug;
332 
333 	if ( bv != NULL ) {
334 		ber->ber_buf = bv->bv_val;
335 		ber->ber_ptr = ber->ber_buf;
336 		ber->ber_end = ber->ber_buf + bv->bv_len;
337 	}
338 
339 	assert( LBER_VALID( ber ) );
340 }
341 
342 /* OLD U-Mich ber_init() */
343 void
344 ber_init_w_nullc( BerElement *ber, int options )
345 {
346 	ber_init2( ber, NULL, options );
347 }
348 
349 /* New C-API ber_init() */
350 /* This function constructs a BerElement containing a copy
351 ** of the data in the bv argument.
352 */
353 BerElement *
354 ber_init( struct berval *bv )
355 {
356 	BerElement *ber;
357 
358 	assert( bv != NULL );
359 
360 	if ( bv == NULL ) {
361 		return NULL;
362 	}
363 
364 	ber = ber_alloc_t( 0 );
365 
366 	if( ber == NULL ) {
367 		/* allocation failed */
368 		return NULL;
369 	}
370 
371 	/* copy the data */
372 	if ( ((ber_len_t) ber_write ( ber, bv->bv_val, bv->bv_len, 0 ))
373 		!= bv->bv_len )
374 	{
375 		/* write failed, so free and return NULL */
376 		ber_free( ber, 1 );
377 		return NULL;
378 	}
379 
380 	ber_reset( ber, 1 );	/* reset the pointer to the start of the buffer */
381 	return ber;
382 }
383 
384 /* New C-API ber_flatten routine */
385 /* This routine allocates a struct berval whose contents are a BER
386 ** encoding taken from the ber argument.  The bvPtr pointer points to
387 ** the returned berval.
388 **
389 ** ber_flatten2 is the same, but uses a struct berval passed by
390 ** the caller. If alloc is 0 the returned bv uses the ber buf directly.
391 */
392 int ber_flatten2(
393 	BerElement *ber,
394 	struct berval *bv,
395 	int alloc )
396 {
397 	assert( bv != NULL );
398 
399 	if ( bv == NULL ) {
400 		return -1;
401 	}
402 
403 	if ( ber == NULL ) {
404 		/* ber is null, create an empty berval */
405 		bv->bv_val = NULL;
406 		bv->bv_len = 0;
407 
408 	} else {
409 		/* copy the berval */
410 		ber_len_t len = ber_pvt_ber_write( ber );
411 
412 		if ( alloc ) {
413 			bv->bv_val = (char *) ber_memalloc_x( len + 1, ber->ber_memctx );
414 			if ( bv->bv_val == NULL ) {
415 				return -1;
416 			}
417 			AC_MEMCPY( bv->bv_val, ber->ber_buf, len );
418 		} else {
419 			bv->bv_val = ber->ber_buf;
420 		}
421 		bv->bv_val[len] = '\0';
422 		bv->bv_len = len;
423 	}
424 	return 0;
425 }
426 
427 int ber_flatten(
428 	BerElement *ber,
429 	struct berval **bvPtr)
430 {
431 	struct berval *bv;
432 	int rc;
433 
434 	assert( bvPtr != NULL );
435 
436 	if(bvPtr == NULL) {
437 		return -1;
438 	}
439 
440 	bv = ber_memalloc_x( sizeof(struct berval), ber->ber_memctx );
441 	if ( bv == NULL ) {
442 		return -1;
443 	}
444 	rc = ber_flatten2(ber, bv, 1);
445 	if (rc == -1) {
446 		ber_memfree_x(bv, ber->ber_memctx);
447 	} else {
448 		*bvPtr = bv;
449 	}
450 	return rc;
451 }
452 
453 void
454 ber_reset( BerElement *ber, int was_writing )
455 {
456 	assert( ber != NULL );
457 	assert( LBER_VALID( ber ) );
458 
459 	if ( was_writing ) {
460 		ber->ber_end = ber->ber_ptr;
461 		ber->ber_ptr = ber->ber_buf;
462 
463 	} else {
464 		ber->ber_ptr = ber->ber_end;
465 	}
466 
467 	ber->ber_rwptr = NULL;
468 }
469 
470 /*
471  * A rewrite of ber_get_next that can safely be called multiple times
472  * for the same packet. It will simply continue where it stopped until
473  * a full packet is read.
474  */
475 
476 #define LENSIZE	4
477 
478 ber_tag_t
479 ber_get_next(
480 	Sockbuf *sb,
481 	ber_len_t *len,
482 	BerElement *ber )
483 {
484 	assert( sb != NULL );
485 	assert( len != NULL );
486 	assert( ber != NULL );
487 
488 	assert( SOCKBUF_VALID( sb ) );
489 	assert( LBER_VALID( ber ) );
490 
491 	if ( ber->ber_debug & LDAP_DEBUG_TRACE ) {
492 		ber_log_printf( LDAP_DEBUG_TRACE, ber->ber_debug,
493 			"ber_get_next\n" );
494 	}
495 
496 	/*
497 	 * Any ber element looks like this: tag length contents.
498 	 * Assuming everything's ok, we return the tag byte (we
499 	 * can assume a single byte), return the length in len,
500 	 * and the rest of the undecoded element in buf.
501 	 *
502 	 * Assumptions:
503 	 *	1) small tags (less than 128)
504 	 *	2) definite lengths
505 	 *	3) primitive encodings used whenever possible
506 	 *
507 	 * The code also handles multi-byte tags. The first few bytes
508 	 * of the message are read to check for multi-byte tags and
509 	 * lengths. These bytes are temporarily stored in the ber_tag,
510 	 * ber_len, and ber_usertag fields of the berelement until
511 	 * tag/len parsing is complete. After this parsing, any leftover
512 	 * bytes and the rest of the message are copied into the ber_buf.
513 	 *
514 	 * We expect tag and len to be at most 32 bits wide.
515 	 */
516 
517 	if (ber->ber_rwptr == NULL) {
518 		assert( ber->ber_buf == NULL );
519 		ber->ber_rwptr = (char *) &ber->ber_len-1;
520 		ber->ber_ptr = ber->ber_rwptr;
521 		ber->ber_tag = 0;
522 	}
523 
524 	while (ber->ber_rwptr > (char *)&ber->ber_tag && ber->ber_rwptr <
525 		(char *)&ber->ber_len + LENSIZE*2) {
526 		ber_slen_t sblen;
527 		char buf[sizeof(ber->ber_len)-1];
528 		ber_len_t tlen = 0;
529 
530 		/* The tag & len can be at most 9 bytes; we try to read up to 8 here */
531 		sock_errset(0);
532 		sblen=((char *)&ber->ber_len + LENSIZE*2 - 1)-ber->ber_rwptr;
533 		/* Trying to read the last len byte of a 9 byte tag+len */
534 		if (sblen<1)
535 			sblen = 1;
536 		sblen=ber_int_sb_read( sb, ber->ber_rwptr, sblen );
537 		if (sblen<=0) return LBER_DEFAULT;
538 		ber->ber_rwptr += sblen;
539 
540 		/* We got at least one byte, try to parse the tag. */
541 		if (ber->ber_ptr == (char *)&ber->ber_len-1) {
542 			ber_tag_t tag;
543 			unsigned char *p = (unsigned char *)ber->ber_ptr;
544 			tag = *p++;
545 			if ((tag & LBER_BIG_TAG_MASK) == LBER_BIG_TAG_MASK) {
546 				ber_len_t i;
547 				for (i=1; (char *)p<ber->ber_rwptr; i++) {
548 					tag <<= 8;
549 					tag |= *p++;
550 					if (!(tag & LBER_MORE_TAG_MASK))
551 						break;
552 					/* Is the tag too big? */
553 					if (i == sizeof(ber_tag_t)-1) {
554 						sock_errset(ERANGE);
555 						return LBER_DEFAULT;
556 					}
557 				}
558 				/* Did we run out of bytes? */
559 				if ((char *)p == ber->ber_rwptr) {
560 #if defined( EWOULDBLOCK )
561 					sock_errset(EWOULDBLOCK);
562 #elif defined( EAGAIN )
563 					sock_errset(EAGAIN);
564 #endif
565 					return LBER_DEFAULT;
566 				}
567 			}
568 			ber->ber_tag = tag;
569 			ber->ber_ptr = (char *)p;
570 		}
571 
572 		if ( ber->ber_ptr == ber->ber_rwptr ) {
573 #if defined( EWOULDBLOCK )
574 			sock_errset(EWOULDBLOCK);
575 #elif defined( EAGAIN )
576 			sock_errset(EAGAIN);
577 #endif
578 			return LBER_DEFAULT;
579 		}
580 
581 		/* Now look for the length */
582 		if (*ber->ber_ptr & 0x80) {	/* multi-byte */
583 			int i;
584 			unsigned char *p = (unsigned char *)ber->ber_ptr;
585 			int llen = *p++ & 0x7f;
586 			if (llen > LENSIZE) {
587 				sock_errset(ERANGE);
588 				return LBER_DEFAULT;
589 			}
590 			/* Not enough bytes? */
591 			if (ber->ber_rwptr - (char *)p < llen) {
592 #if defined( EWOULDBLOCK )
593 				sock_errset(EWOULDBLOCK);
594 #elif defined( EAGAIN )
595 				sock_errset(EAGAIN);
596 #endif
597 				return LBER_DEFAULT;
598 			}
599 			for (i=0; i<llen; i++) {
600 				tlen <<=8;
601 				tlen |= *p++;
602 			}
603 			ber->ber_ptr = (char *)p;
604 		} else {
605 			tlen = *(unsigned char *)ber->ber_ptr++;
606 		}
607 
608 		/* Are there leftover data bytes inside ber->ber_len? */
609 		if (ber->ber_ptr < (char *)&ber->ber_usertag) {
610 			if (ber->ber_rwptr < (char *)&ber->ber_usertag) {
611 				sblen = ber->ber_rwptr - ber->ber_ptr;
612 			} else {
613 				sblen = (char *)&ber->ber_usertag - ber->ber_ptr;
614 			}
615 			AC_MEMCPY(buf, ber->ber_ptr, sblen);
616 			ber->ber_ptr += sblen;
617 		} else {
618 			sblen = 0;
619 		}
620 		ber->ber_len = tlen;
621 
622 		/* now fill the buffer. */
623 
624 		/* make sure length is reasonable */
625 		if ( ber->ber_len == 0 ) {
626 			sock_errset(ERANGE);
627 			return LBER_DEFAULT;
628 		}
629 
630 		if ( sb->sb_max_incoming && ber->ber_len > sb->sb_max_incoming ) {
631 			ber_log_printf( LDAP_DEBUG_CONNS, ber->ber_debug,
632 				"ber_get_next: sockbuf_max_incoming exceeded "
633 				"(%ld > %ld)\n", ber->ber_len, sb->sb_max_incoming );
634 			sock_errset(ERANGE);
635 			return LBER_DEFAULT;
636 		}
637 
638 		if (ber->ber_buf==NULL) {
639 			ber_len_t l = ber->ber_rwptr - ber->ber_ptr;
640 			/* ber->ber_ptr is always <= ber->ber->ber_rwptr.
641 			 * make sure ber->ber_len agrees with what we've
642 			 * already read.
643 			 */
644 			if ( ber->ber_len < sblen + l ) {
645 				sock_errset(ERANGE);
646 				return LBER_DEFAULT;
647 			}
648 			ber->ber_buf = (char *) ber_memalloc_x( ber->ber_len + 1, ber->ber_memctx );
649 			if (ber->ber_buf==NULL) {
650 				return LBER_DEFAULT;
651 			}
652 			ber->ber_end = ber->ber_buf + ber->ber_len;
653 			if (sblen) {
654 				AC_MEMCPY(ber->ber_buf, buf, sblen);
655 			}
656 			if (l > 0) {
657 				AC_MEMCPY(ber->ber_buf + sblen, ber->ber_ptr, l);
658 				sblen += l;
659 			}
660 			*ber->ber_end = '\0';
661 			ber->ber_ptr = ber->ber_buf;
662 			ber->ber_usertag = 0;
663 			if ((ber_len_t)sblen == ber->ber_len) {
664 				goto done;
665 			}
666 			ber->ber_rwptr = ber->ber_buf + sblen;
667 		}
668 	}
669 
670 	if ((ber->ber_rwptr>=ber->ber_buf) && (ber->ber_rwptr<ber->ber_end)) {
671 		ber_slen_t res;
672 		ber_slen_t to_go;
673 
674 		to_go = ber->ber_end - ber->ber_rwptr;
675 		assert( to_go > 0 );
676 
677 		sock_errset(0);
678 		res = ber_int_sb_read( sb, ber->ber_rwptr, to_go );
679 		if (res<=0) return LBER_DEFAULT;
680 		ber->ber_rwptr+=res;
681 
682 		if (res<to_go) {
683 #if defined( EWOULDBLOCK )
684 			sock_errset(EWOULDBLOCK);
685 #elif defined( EAGAIN )
686 			sock_errset(EAGAIN);
687 #endif
688 			return LBER_DEFAULT;
689 		}
690 done:
691 		ber->ber_rwptr = NULL;
692 		*len = ber->ber_len;
693 		if ( ber->ber_debug ) {
694 			ber_log_printf( LDAP_DEBUG_TRACE, ber->ber_debug,
695 				"ber_get_next: tag 0x%lx len %ld contents:\n",
696 				ber->ber_tag, ber->ber_len );
697 			ber_log_dump( LDAP_DEBUG_BER, ber->ber_debug, ber, 1 );
698 		}
699 		return (ber->ber_tag);
700 	}
701 
702 	assert( 0 ); /* ber structure is messed up ?*/
703 	return LBER_DEFAULT;
704 }
705 
706 char *
707 ber_start( BerElement* ber )
708 {
709 	return ber->ber_buf;
710 }
711 
712 int
713 ber_len( BerElement* ber )
714 {
715 	return ( ber->ber_end - ber->ber_buf );
716 }
717 
718 int
719 ber_ptrlen( BerElement* ber )
720 {
721 	return ( ber->ber_ptr - ber->ber_buf );
722 }
723 
724 void
725 ber_rewind ( BerElement * ber )
726 {
727 	ber->ber_rwptr = NULL;
728 	ber->ber_sos = NULL;
729 	ber->ber_end = ber->ber_ptr;
730 	ber->ber_ptr = ber->ber_buf;
731 }
732 
733 int
734 ber_remaining( BerElement * ber )
735 {
736 	return ber_pvt_ber_remaining( ber );
737 }
738