xref: /netbsd-src/external/bsd/openldap/dist/libraries/liblber/io.c (revision 946379e7b37692fc43f68eb0d1c10daa0a7f3b6c)
1 /*	$NetBSD: io.c,v 1.1.1.5 2014/05/28 09:58:41 tron Exp $	*/
2 
3 /* io.c - ber general i/o routines */
4 /* $OpenLDAP$ */
5 /* This work is part of OpenLDAP Software <http://www.openldap.org/>.
6  *
7  * Copyright 1998-2014 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 "portable.h"
34 
35 #include <stdio.h>
36 
37 #include <ac/stdlib.h>
38 
39 #include <ac/ctype.h>
40 #include <ac/errno.h>
41 #include <ac/socket.h>
42 #include <ac/string.h>
43 #include <ac/unistd.h>
44 
45 #ifdef HAVE_IO_H
46 #include <io.h>
47 #endif
48 
49 #include "lber-int.h"
50 #include "ldap_log.h"
51 
52 ber_slen_t
53 ber_skip_data(
54 	BerElement *ber,
55 	ber_len_t len )
56 {
57 	ber_len_t	actuallen, nleft;
58 
59 	assert( ber != NULL );
60 	assert( LBER_VALID( ber ) );
61 
62 	nleft = ber_pvt_ber_remaining( ber );
63 	actuallen = nleft < len ? nleft : len;
64 	ber->ber_ptr += actuallen;
65 	ber->ber_tag = *(unsigned char *)ber->ber_ptr;
66 
67 	return( (ber_slen_t) actuallen );
68 }
69 
70 /*
71  * Read from the ber buffer.  The caller must maintain ber->ber_tag.
72  * Do not use to read whole tags.  See ber_get_tag() and ber_skip_data().
73  */
74 ber_slen_t
75 ber_read(
76 	BerElement *ber,
77 	char *buf,
78 	ber_len_t len )
79 {
80 	ber_len_t	actuallen, nleft;
81 
82 	assert( ber != NULL );
83 	assert( buf != NULL );
84 	assert( LBER_VALID( ber ) );
85 
86 	nleft = ber_pvt_ber_remaining( ber );
87 	actuallen = nleft < len ? nleft : len;
88 
89 	AC_MEMCPY( buf, ber->ber_ptr, actuallen );
90 
91 	ber->ber_ptr += actuallen;
92 
93 	return( (ber_slen_t) actuallen );
94 }
95 
96 /*
97  * Write to the ber buffer.
98  * Note that ber_start_seqorset/ber_put_seqorset() bypass ber_write().
99  */
100 ber_slen_t
101 ber_write(
102 	BerElement *ber,
103 	LDAP_CONST char *buf,
104 	ber_len_t len,
105 	int zero )	/* nonzero is unsupported from OpenLDAP 2.4.18 */
106 {
107 	char **p;
108 
109 	assert( ber != NULL );
110 	assert( buf != NULL );
111 	assert( LBER_VALID( ber ) );
112 
113 	if ( zero != 0 ) {
114 		ber_log_printf( LDAP_DEBUG_ANY, ber->ber_debug, "%s",
115 			"ber_write: nonzero 4th argument not supported\n" );
116 		return( -1 );
117 	}
118 
119 	p = ber->ber_sos_ptr == NULL ? &ber->ber_ptr : &ber->ber_sos_ptr;
120 	if ( len > (ber_len_t) (ber->ber_end - *p) ) {
121 		if ( ber_realloc( ber, len ) != 0 ) return( -1 );
122 	}
123 	AC_MEMCPY( *p, buf, len );
124 	*p += len;
125 
126 	return( (ber_slen_t) len );
127 }
128 
129 /* Resize the ber buffer */
130 int
131 ber_realloc( BerElement *ber, ber_len_t len )
132 {
133 	ber_len_t	total, offset, sos_offset;
134 	char		*buf;
135 
136 	assert( ber != NULL );
137 	assert( LBER_VALID( ber ) );
138 
139 	/* leave room for ber_flatten() to \0-terminate ber_buf */
140 	if ( ++len == 0 ) {
141 		return( -1 );
142 	}
143 
144 	total = ber_pvt_ber_total( ber );
145 
146 #define LBER_EXBUFSIZ	4060 /* a few words less than 2^N for binary buddy */
147 #if defined( LBER_EXBUFSIZ ) && LBER_EXBUFSIZ > 0
148 # ifndef notdef
149 	/* don't realloc by small amounts */
150 	total += len < LBER_EXBUFSIZ ? LBER_EXBUFSIZ : len;
151 # else
152 	{	/* not sure what value this adds.  reduce fragmentation? */
153 		ber_len_t have = (total + (LBER_EXBUFSIZE - 1)) / LBER_EXBUFSIZ;
154 		ber_len_t need = (len + (LBER_EXBUFSIZ - 1)) / LBER_EXBUFSIZ;
155 		total = ( have + need ) * LBER_EXBUFSIZ;
156 	}
157 # endif
158 #else
159 	total += len;	/* realloc just what's needed */
160 #endif
161 
162 	if ( total < len || total > (ber_len_t)-1 / 2 /* max ber_slen_t */ ) {
163 		return( -1 );
164 	}
165 
166 	buf = ber->ber_buf;
167 	offset = ber->ber_ptr - buf;
168 	sos_offset = ber->ber_sos_ptr ? ber->ber_sos_ptr - buf : 0;
169 	/* if ber_sos_ptr != NULL, it is > ber_buf so that sos_offset > 0 */
170 
171 	buf = (char *) ber_memrealloc_x( buf, total, ber->ber_memctx );
172 	if ( buf == NULL ) {
173 		return( -1 );
174 	}
175 
176 	ber->ber_buf = buf;
177 	ber->ber_end = buf + total;
178 	ber->ber_ptr = buf + offset;
179 	if ( sos_offset )
180 		ber->ber_sos_ptr = buf + sos_offset;
181 
182 	return( 0 );
183 }
184 
185 void
186 ber_free_buf( BerElement *ber )
187 {
188 	assert( LBER_VALID( ber ) );
189 
190 	if ( ber->ber_buf) ber_memfree_x( ber->ber_buf, ber->ber_memctx );
191 
192 	ber->ber_buf = NULL;
193 	ber->ber_sos_ptr = NULL;
194 	ber->ber_valid = LBER_UNINITIALIZED;
195 }
196 
197 void
198 ber_free( BerElement *ber, int freebuf )
199 {
200 	if( ber == NULL ) {
201 		LDAP_MEMORY_DEBUG_ASSERT( ber != NULL );
202 		return;
203 	}
204 
205 	if( freebuf ) ber_free_buf( ber );
206 
207 	ber_memfree_x( (char *) ber, ber->ber_memctx );
208 }
209 
210 int
211 ber_flush( Sockbuf *sb, BerElement *ber, int freeit )
212 {
213 	return ber_flush2( sb, ber,
214 		freeit ? LBER_FLUSH_FREE_ON_SUCCESS
215 			: LBER_FLUSH_FREE_NEVER );
216 }
217 
218 int
219 ber_flush2( Sockbuf *sb, BerElement *ber, int freeit )
220 {
221 	ber_len_t	towrite;
222 	ber_slen_t	rc;
223 
224 	assert( sb != NULL );
225 	assert( ber != NULL );
226 	assert( SOCKBUF_VALID( sb ) );
227 	assert( LBER_VALID( ber ) );
228 
229 	if ( ber->ber_rwptr == NULL ) {
230 		ber->ber_rwptr = ber->ber_buf;
231 	}
232 	towrite = ber->ber_ptr - ber->ber_rwptr;
233 
234 	if ( sb->sb_debug ) {
235 		ber_log_printf( LDAP_DEBUG_TRACE, sb->sb_debug,
236 			"ber_flush2: %ld bytes to sd %ld%s\n",
237 			towrite, (long) sb->sb_fd,
238 			ber->ber_rwptr != ber->ber_buf ?  " (re-flush)" : "" );
239 		ber_log_bprint( LDAP_DEBUG_BER, sb->sb_debug,
240 			ber->ber_rwptr, towrite );
241 	}
242 
243 	while ( towrite > 0 ) {
244 #ifdef LBER_TRICKLE
245 		sleep(1);
246 		rc = ber_int_sb_write( sb, ber->ber_rwptr, 1 );
247 #else
248 		rc = ber_int_sb_write( sb, ber->ber_rwptr, towrite );
249 #endif
250 		if ( rc <= 0 ) {
251 			if ( freeit & LBER_FLUSH_FREE_ON_ERROR ) ber_free( ber, 1 );
252 			return -1;
253 		}
254 		towrite -= rc;
255 		ber->ber_rwptr += rc;
256 	}
257 
258 	if ( freeit & LBER_FLUSH_FREE_ON_SUCCESS ) ber_free( ber, 1 );
259 
260 	return 0;
261 }
262 
263 BerElement *
264 ber_alloc_t( int options )
265 {
266 	BerElement	*ber;
267 
268 	ber = (BerElement *) LBER_CALLOC( 1, sizeof(BerElement) );
269 
270 	if ( ber == NULL ) {
271 		return NULL;
272 	}
273 
274 	ber->ber_valid = LBER_VALID_BERELEMENT;
275 	ber->ber_tag = LBER_DEFAULT;
276 	ber->ber_options = options;
277 	ber->ber_debug = ber_int_debug;
278 
279 	assert( LBER_VALID( ber ) );
280 	return ber;
281 }
282 
283 BerElement *
284 ber_alloc( void )	/* deprecated */
285 {
286 	return ber_alloc_t( 0 );
287 }
288 
289 BerElement *
290 der_alloc( void )	/* deprecated */
291 {
292 	return ber_alloc_t( LBER_USE_DER );
293 }
294 
295 BerElement *
296 ber_dup( BerElement *ber )
297 {
298 	BerElement	*new;
299 
300 	assert( ber != NULL );
301 	assert( LBER_VALID( ber ) );
302 
303 	if ( (new = ber_alloc_t( ber->ber_options )) == NULL ) {
304 		return NULL;
305 	}
306 
307 	*new = *ber;
308 
309 	assert( LBER_VALID( new ) );
310 	return( new );
311 }
312 
313 
314 void
315 ber_init2( BerElement *ber, struct berval *bv, int options )
316 {
317 	assert( ber != NULL );
318 
319 	(void) memset( (char *)ber, '\0', sizeof( BerElement ));
320 	ber->ber_valid = LBER_VALID_BERELEMENT;
321 	ber->ber_tag = LBER_DEFAULT;
322 	ber->ber_options = (char) options;
323 	ber->ber_debug = ber_int_debug;
324 
325 	if ( bv != NULL ) {
326 		ber->ber_buf = bv->bv_val;
327 		ber->ber_ptr = ber->ber_buf;
328 		ber->ber_end = ber->ber_buf + bv->bv_len;
329 	}
330 
331 	assert( LBER_VALID( ber ) );
332 }
333 
334 /* OLD U-Mich ber_init() */
335 void
336 ber_init_w_nullc( BerElement *ber, int options )
337 {
338 	ber_init2( ber, NULL, options );
339 }
340 
341 /* New C-API ber_init() */
342 /* This function constructs a BerElement containing a copy
343 ** of the data in the bv argument.
344 */
345 BerElement *
346 ber_init( struct berval *bv )
347 {
348 	BerElement *ber;
349 
350 	assert( bv != NULL );
351 
352 	if ( bv == NULL ) {
353 		return NULL;
354 	}
355 
356 	ber = ber_alloc_t( 0 );
357 
358 	if( ber == NULL ) {
359 		/* allocation failed */
360 		return NULL;
361 	}
362 
363 	/* copy the data */
364 	if ( ((ber_len_t) ber_write ( ber, bv->bv_val, bv->bv_len, 0 ))
365 		!= bv->bv_len )
366 	{
367 		/* write failed, so free and return NULL */
368 		ber_free( ber, 1 );
369 		return NULL;
370 	}
371 
372 	ber_reset( ber, 1 );	/* reset the pointer to the start of the buffer */
373 	return ber;
374 }
375 
376 /* New C-API ber_flatten routine */
377 /* This routine allocates a struct berval whose contents are a BER
378 ** encoding taken from the ber argument.  The bvPtr pointer points to
379 ** the returned berval.
380 **
381 ** ber_flatten2 is the same, but uses a struct berval passed by
382 ** the caller. If alloc is 0 the returned bv uses the ber buf directly.
383 */
384 int ber_flatten2(
385 	BerElement *ber,
386 	struct berval *bv,
387 	int alloc )
388 {
389 	assert( bv != NULL );
390 
391 	if ( bv == NULL ) {
392 		return -1;
393 	}
394 
395 	if ( ber == NULL ) {
396 		/* ber is null, create an empty berval */
397 		bv->bv_val = NULL;
398 		bv->bv_len = 0;
399 
400 	} else if ( ber->ber_sos_ptr != NULL ) {
401 		/* unmatched "{" and "}" */
402 		return -1;
403 
404 	} else {
405 		/* copy the berval */
406 		ber_len_t len = ber_pvt_ber_write( ber );
407 
408 		if ( alloc ) {
409 			bv->bv_val = (char *) ber_memalloc_x( len + 1, ber->ber_memctx );
410 			if ( bv->bv_val == NULL ) {
411 				return -1;
412 			}
413 			AC_MEMCPY( bv->bv_val, ber->ber_buf, len );
414 			bv->bv_val[len] = '\0';
415 		} else if ( ber->ber_buf != NULL ) {
416 			bv->bv_val = ber->ber_buf;
417 			bv->bv_val[len] = '\0';
418 		} else {
419 			bv->bv_val = "";
420 		}
421 		bv->bv_len = len;
422 	}
423 	return 0;
424 }
425 
426 int ber_flatten(
427 	BerElement *ber,
428 	struct berval **bvPtr)
429 {
430 	struct berval *bv;
431 	int rc;
432 
433 	assert( bvPtr != NULL );
434 
435 	if(bvPtr == NULL) {
436 		return -1;
437 	}
438 
439 	bv = ber_memalloc_x( sizeof(struct berval), ber->ber_memctx );
440 	if ( bv == NULL ) {
441 		return -1;
442 	}
443 	rc = ber_flatten2(ber, bv, 1);
444 	if (rc == -1) {
445 		ber_memfree_x(bv, ber->ber_memctx);
446 	} else {
447 		*bvPtr = bv;
448 	}
449 	return rc;
450 }
451 
452 void
453 ber_reset( BerElement *ber, int was_writing )
454 {
455 	assert( ber != NULL );
456 	assert( LBER_VALID( ber ) );
457 
458 	if ( was_writing ) {
459 		ber->ber_end = ber->ber_ptr;
460 		ber->ber_ptr = ber->ber_buf;
461 
462 	} else {
463 		ber->ber_ptr = ber->ber_end;
464 	}
465 
466 	ber->ber_rwptr = NULL;
467 }
468 
469 /*
470  * A rewrite of ber_get_next that can safely be called multiple times
471  * for the same packet. It will simply continue where it stopped until
472  * a full packet is read.
473  */
474 
475 #define LENSIZE	4
476 
477 ber_tag_t
478 ber_get_next(
479 	Sockbuf *sb,
480 	ber_len_t *len,
481 	BerElement *ber )
482 {
483 	assert( sb != NULL );
484 	assert( len != NULL );
485 	assert( ber != NULL );
486 	assert( SOCKBUF_VALID( sb ) );
487 	assert( LBER_VALID( ber ) );
488 
489 	if ( ber->ber_debug & LDAP_DEBUG_TRACE ) {
490 		ber_log_printf( LDAP_DEBUG_TRACE, ber->ber_debug,
491 			"ber_get_next\n" );
492 	}
493 
494 	/*
495 	 * Any ber element looks like this: tag length contents.
496 	 * Assuming everything's ok, we return the tag byte (we
497 	 * can assume a single byte), return the length in len,
498 	 * and the rest of the undecoded element in buf.
499 	 *
500 	 * Assumptions:
501 	 *	1) small tags (less than 128)
502 	 *	2) definite lengths
503 	 *	3) primitive encodings used whenever possible
504 	 *
505 	 * The code also handles multi-byte tags. The first few bytes
506 	 * of the message are read to check for multi-byte tags and
507 	 * lengths. These bytes are temporarily stored in the ber_tag,
508 	 * ber_len, and ber_usertag fields of the berelement until
509 	 * tag/len parsing is complete. After this parsing, any leftover
510 	 * bytes and the rest of the message are copied into the ber_buf.
511 	 *
512 	 * We expect tag and len to be at most 32 bits wide.
513 	 */
514 
515 	if (ber->ber_rwptr == NULL) {
516 		assert( ber->ber_buf == NULL );
517 		ber->ber_rwptr = (char *) &ber->ber_len-1;
518 		ber->ber_ptr = ber->ber_rwptr;
519 		ber->ber_tag = 0;
520 	}
521 
522 	while (ber->ber_rwptr > (char *)&ber->ber_tag && ber->ber_rwptr <
523 		(char *)&ber->ber_len + LENSIZE*2) {
524 		ber_slen_t sblen;
525 		char buf[sizeof(ber->ber_len)-1];
526 		ber_len_t tlen = 0;
527 
528 		/* The tag & len can be at most 9 bytes; we try to read up to 8 here */
529 		sock_errset(0);
530 		sblen=((char *)&ber->ber_len + LENSIZE*2 - 1)-ber->ber_rwptr;
531 		/* Trying to read the last len byte of a 9 byte tag+len */
532 		if (sblen<1)
533 			sblen = 1;
534 		sblen=ber_int_sb_read( sb, ber->ber_rwptr, sblen );
535 		if (sblen<=0) return LBER_DEFAULT;
536 		ber->ber_rwptr += sblen;
537 
538 		/* We got at least one byte, try to parse the tag. */
539 		if (ber->ber_ptr == (char *)&ber->ber_len-1) {
540 			ber_tag_t tag;
541 			unsigned char *p = (unsigned char *)ber->ber_ptr;
542 			tag = *p++;
543 			if ((tag & LBER_BIG_TAG_MASK) == LBER_BIG_TAG_MASK) {
544 				ber_len_t i;
545 				for (i=1; (char *)p<ber->ber_rwptr; i++) {
546 					tag <<= 8;
547 					tag |= *p++;
548 					if (!(tag & LBER_MORE_TAG_MASK))
549 						break;
550 					/* Is the tag too big? */
551 					if (i == sizeof(ber_tag_t)-1) {
552 						sock_errset(ERANGE);
553 						return LBER_DEFAULT;
554 					}
555 				}
556 				/* Did we run out of bytes? */
557 				if ((char *)p == ber->ber_rwptr) {
558 					sock_errset(EWOULDBLOCK);
559 					return LBER_DEFAULT;
560 				}
561 			}
562 			ber->ber_tag = tag;
563 			ber->ber_ptr = (char *)p;
564 		}
565 
566 		if ( ber->ber_ptr == ber->ber_rwptr ) {
567 			sock_errset(EWOULDBLOCK);
568 			return LBER_DEFAULT;
569 		}
570 
571 		/* Now look for the length */
572 		if (*ber->ber_ptr & 0x80) {	/* multi-byte */
573 			int i;
574 			unsigned char *p = (unsigned char *)ber->ber_ptr;
575 			int llen = *p++ & 0x7f;
576 			if (llen > LENSIZE) {
577 				sock_errset(ERANGE);
578 				return LBER_DEFAULT;
579 			}
580 			/* Not enough bytes? */
581 			if (ber->ber_rwptr - (char *)p < llen) {
582 				sock_errset(EWOULDBLOCK);
583 				return LBER_DEFAULT;
584 			}
585 			for (i=0; i<llen; i++) {
586 				tlen <<=8;
587 				tlen |= *p++;
588 			}
589 			ber->ber_ptr = (char *)p;
590 		} else {
591 			tlen = *(unsigned char *)ber->ber_ptr++;
592 		}
593 
594 		/* Are there leftover data bytes inside ber->ber_len? */
595 		if (ber->ber_ptr < (char *)&ber->ber_usertag) {
596 			if (ber->ber_rwptr < (char *)&ber->ber_usertag) {
597 				sblen = ber->ber_rwptr - ber->ber_ptr;
598 			} else {
599 				sblen = (char *)&ber->ber_usertag - ber->ber_ptr;
600 			}
601 			AC_MEMCPY(buf, ber->ber_ptr, sblen);
602 			ber->ber_ptr += sblen;
603 		} else {
604 			sblen = 0;
605 		}
606 		ber->ber_len = tlen;
607 
608 		/* now fill the buffer. */
609 
610 		/* make sure length is reasonable */
611 		if ( ber->ber_len == 0 ) {
612 			sock_errset(ERANGE);
613 			return LBER_DEFAULT;
614 		}
615 
616 		if ( sb->sb_max_incoming && ber->ber_len > sb->sb_max_incoming ) {
617 			ber_log_printf( LDAP_DEBUG_CONNS, ber->ber_debug,
618 				"ber_get_next: sockbuf_max_incoming exceeded "
619 				"(%ld > %ld)\n", ber->ber_len, sb->sb_max_incoming );
620 			sock_errset(ERANGE);
621 			return LBER_DEFAULT;
622 		}
623 
624 		if (ber->ber_buf==NULL) {
625 			ber_len_t l = ber->ber_rwptr - ber->ber_ptr;
626 			/* ber->ber_ptr is always <= ber->ber->ber_rwptr.
627 			 * make sure ber->ber_len agrees with what we've
628 			 * already read.
629 			 */
630 			if ( ber->ber_len < sblen + l ) {
631 				sock_errset(ERANGE);
632 				return LBER_DEFAULT;
633 			}
634 			ber->ber_buf = (char *) ber_memalloc_x( ber->ber_len + 1, ber->ber_memctx );
635 			if (ber->ber_buf==NULL) {
636 				return LBER_DEFAULT;
637 			}
638 			ber->ber_end = ber->ber_buf + ber->ber_len;
639 			if (sblen) {
640 				AC_MEMCPY(ber->ber_buf, buf, sblen);
641 			}
642 			if (l > 0) {
643 				AC_MEMCPY(ber->ber_buf + sblen, ber->ber_ptr, l);
644 				sblen += l;
645 			}
646 			*ber->ber_end = '\0';
647 			ber->ber_ptr = ber->ber_buf;
648 			ber->ber_usertag = 0;
649 			if ((ber_len_t)sblen == ber->ber_len) {
650 				goto done;
651 			}
652 			ber->ber_rwptr = ber->ber_buf + sblen;
653 		}
654 	}
655 
656 	if ((ber->ber_rwptr>=ber->ber_buf) && (ber->ber_rwptr<ber->ber_end)) {
657 		ber_slen_t res;
658 		ber_slen_t to_go;
659 
660 		to_go = ber->ber_end - ber->ber_rwptr;
661 		assert( to_go > 0 );
662 
663 		sock_errset(0);
664 		res = ber_int_sb_read( sb, ber->ber_rwptr, to_go );
665 		if (res<=0) return LBER_DEFAULT;
666 		ber->ber_rwptr+=res;
667 
668 		if (res<to_go) {
669 			sock_errset(EWOULDBLOCK);
670 			return LBER_DEFAULT;
671 		}
672 done:
673 		ber->ber_rwptr = NULL;
674 		*len = ber->ber_len;
675 		if ( ber->ber_debug ) {
676 			ber_log_printf( LDAP_DEBUG_TRACE, ber->ber_debug,
677 				"ber_get_next: tag 0x%lx len %ld contents:\n",
678 				ber->ber_tag, ber->ber_len );
679 			ber_log_dump( LDAP_DEBUG_BER, ber->ber_debug, ber, 1 );
680 		}
681 		return (ber->ber_tag);
682 	}
683 
684 	assert( 0 ); /* ber structure is messed up ?*/
685 	return LBER_DEFAULT;
686 }
687 
688 char *
689 ber_start( BerElement* ber )
690 {
691 	return ber->ber_buf;
692 }
693 
694 int
695 ber_len( BerElement* ber )
696 {
697 	return ( ber->ber_end - ber->ber_buf );
698 }
699 
700 int
701 ber_ptrlen( BerElement* ber )
702 {
703 	return ( ber->ber_ptr - ber->ber_buf );
704 }
705 
706 void
707 ber_rewind ( BerElement * ber )
708 {
709 	ber->ber_rwptr = NULL;
710 	ber->ber_sos_ptr = NULL;
711 	ber->ber_end = ber->ber_ptr;
712 	ber->ber_ptr = ber->ber_buf;
713 #if 0	/* TODO: Should we add this? */
714 	ber->ber_tag = LBER_DEFAULT;
715 	ber->ber_usertag = 0;
716 #endif
717 }
718 
719 int
720 ber_remaining( BerElement * ber )
721 {
722 	return ber_pvt_ber_remaining( ber );
723 }
724