1 /* decode.c - ber input decoding routines */
3 /* This work is part of OpenLDAP Software <http://www.openldap.org/>.
5 * Copyright 1998-2017 The OpenLDAP Foundation.
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted only as authorized by the OpenLDAP
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>.
16 /* Portions Copyright (c) 1990 Regents of the University of Michigan.
17 * All rights reserved.
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.
27 * This work was originally developed by the University of Michigan
28 * (as part of U-MICH LDAP).
35 #include <ac/stdlib.h>
36 #include <ac/stdarg.h>
37 #include <ac/string.h>
38 #include <ac/socket.h>
43 /* out->bv_len should be the buffer size on input */
45 ber_decode_oid( BerValue *in, BerValue *out )
47 const unsigned char *der;
54 assert( out != NULL );
56 /* need 4 chars/inbyte + \0 for input={7f 7f 7f...} */
57 if ( !out->bv_val || (out->bv_len+3)/4 <= in->bv_len )
61 der = (unsigned char *) in->bv_val;
63 for ( i=0; i < in->bv_len; i++ ) {
65 if ( !( der[i] & 0x80 )) {
67 /* Initial "x.y": val=x*40+y, x<=2, y<40 if x<2 */
69 val1 = (val < 80 ? val/40 : 2);
71 ptr += sprintf( ptr, "%u", val1 );
73 ptr += sprintf( ptr, ".%lu", val );
75 } else if ( val - 1UL < LBER_OID_COMPONENT_MAX >> 7 ) {
78 /* val would overflow, or is 0 from invalid initial 0x80 octet */
82 if ( ptr == NULL || val != 0 )
85 out->bv_len = ptr - out->bv_val;
89 /* Return tag, with *bv = rest of element (starting at length octets) */
91 ber_tag_and_rest( const BerElement *ber, struct berval *bv )
97 assert( ber != NULL );
98 assert( LBER_VALID( ber ) );
100 ptr = (unsigned char *) ber->ber_ptr;
101 rest = (unsigned char *) ber->ber_end - ptr;
107 if ( (char *) ptr == ber->ber_buf ) {
112 if ( (tag & LBER_BIG_TAG_MASK) != LBER_BIG_TAG_MASK ) {
121 tag |= *ptr++ & 0xffU;
124 if ( ! (tag & LBER_MORE_TAG_MASK) ) {
127 } while ( tag <= (ber_tag_t)-1 / 256 );
130 /* Error or unsupported tag size */
135 bv->bv_val = (char *) ptr;
139 /* Return the tag - LBER_DEFAULT returned means trouble */
141 ber_get_tag( BerElement *ber )
144 ber_tag_t tag = ber_tag_and_rest( ber, &bv );
146 ber->ber_ptr = bv.bv_val;
150 /* Return next element's tag and point *bv at its contents in-place */
152 ber_peek_element( const BerElement *ber, struct berval *bv )
159 assert( bv != NULL );
162 * Any ber element looks like this: tag length contents.
163 * Assuming everything's ok, we return the tag, and point
164 * bv at the contents.
167 * 1) definite lengths
168 * 2) primitive encodings used whenever possible
174 * First, we read the tag.
176 tag = ber_tag_and_rest( ber, bv );
179 ptr = (unsigned char *) bv->bv_val;
180 if ( tag == LBER_DEFAULT || rest == 0 ) {
185 * Next, read the length. The first octet determines the length
186 * of the length. If bit 8 is 0, the length is the short form,
187 * otherwise if the octet != 0x80 it's the long form, otherwise
188 * the ber element has the unsupported indefinite-length format.
189 * Lengths that do not fit in a ber_len_t are not accepted.
197 if ( len - 1U > sizeof(ber_len_t) - 1U || rest < len ) {
198 /* Indefinite-length/too long length/not enough data */
204 for( len = *ptr++ & 0xffU; --i; len |= *ptr++ & 0xffU ) {
209 /* BER element should have enough data left */
216 bv->bv_val = (char *) ptr;
220 /* Move past next element, point *bv at it in-place, and return its tag.
221 * The caller may \0-terminate *bv, as next octet is saved in ber->ber_tag.
222 * Similar to ber_get_stringbv(ber, bv, LBER_BV_NOTERM) except on error.
225 ber_skip_element( BerElement *ber, struct berval *bv )
227 ber_tag_t tag = ber_peek_element( ber, bv );
229 if ( tag != LBER_DEFAULT ) {
230 ber->ber_ptr = bv->bv_val + bv->bv_len;
231 ber->ber_tag = *(unsigned char *) ber->ber_ptr;
237 /* Move past next element, point *bv at the complete element in-place, and
238 * return its tag. The caller may \0-terminate *bv, as next octet is saved in
239 * ber->ber_tag. Similar to ber_skip_element(ber, bv) except the tag+length
240 * header is also included in *bv.
243 ber_skip_raw( BerElement *ber, struct berval *bv )
245 char *val = ber->ber_ptr;
246 ber_tag_t tag = ber_skip_element( ber, bv );
248 if ( tag != LBER_DEFAULT ) {
249 bv->bv_len += bv->bv_val - val;
262 ber_tag_t tag = ber_peek_element( ber, &bv );
269 ber_skip_tag( BerElement *ber, ber_len_t *lenp )
272 ber_tag_t tag = ber_peek_element( ber, &bv );
274 ber->ber_ptr = bv.bv_val;
275 ber->ber_tag = *(unsigned char *) ber->ber_ptr;
287 ber_tag_t tag = ber_skip_element( ber, &bv );
289 if ( tag == LBER_DEFAULT ) {
293 return ber_decode_int( &bv, num ) ? LBER_DEFAULT : tag;
297 ber_decode_int( const struct berval *bv, ber_int_t *num )
299 ber_len_t len = bv->bv_len;
300 if ( len > sizeof(ber_int_t) )
303 assert( num != NULL );
305 /* parse two's complement integer */
307 unsigned char *buf = (unsigned char *) bv->bv_val;
309 ber_int_t netnum = buf[0] & 0xff;
312 netnum = (netnum ^ 0x80) - 0x80;
314 /* shift in the bytes */
315 for( i = 1; i < len; i++ ) {
316 netnum = (netnum << 8 ) | buf[i];
333 return ber_get_int( ber, num );
345 if ( (tag = ber_skip_element( ber, &bv )) == LBER_DEFAULT ) {
349 /* must fit within allocated space with termination */
350 if ( bv.bv_len >= *len ) {
354 memcpy( buf, bv.bv_val, bv.bv_len );
355 buf[bv.bv_len] = '\0';
361 /* Definitions for get_string vector
363 * ChArray, BvArray, and BvVec are self-explanatory.
364 * BvOff is a struct berval embedded in an array of larger structures
365 * of siz bytes at off bytes from the beginning of the struct.
367 enum bgbvc { ChArray, BvArray, BvVec, BvOff };
369 /* Use this single cookie for state, to keep actual
370 * stack use to the absolute minimum.
372 typedef struct bgbvr {
373 const enum bgbvc choice;
374 const int option; /* (ALLOC unless BvOff) | (STRING if ChArray) */
375 ber_len_t siz; /* input array element size, output count */
376 ber_len_t off; /* BvOff offset to the struct berval */
381 ber_get_stringbvl( BerElement *ber, bgbvr *b )
385 ber_len_t tot_size = 0, siz = b->siz;
387 struct berval bv, *bvp = NULL;
389 char **ca; /* ChArray */
390 BerVarray ba; /* BvArray */
391 struct berval **bv; /* BvVec */
392 char *bo; /* BvOff */
395 tag = ber_skip_tag( ber, &bv.bv_len );
397 if ( tag != LBER_DEFAULT ) {
400 last = orig + bv.bv_len;
402 for ( ; ber->ber_ptr < last; i++, tot_size += siz ) {
403 if ( ber_skip_element( ber, &bv ) == LBER_DEFAULT )
406 if ( ber->ber_ptr != last ) {
412 ber->ber_tag = *(unsigned char *) orig;
420 /* Allocate and NULL-terminate the result vector */
421 b->result = ber_memalloc_x( tot_size + siz, ber->ber_memctx );
422 if ( b->result == NULL ) {
432 res.ba[i].bv_val = NULL;
439 res.bo = (char *) b->result + b->off;
440 ((struct berval *) (res.bo + tot_size))->bv_val = NULL;
447 tag = ber_get_stringbv( ber, &bv, b->option );
448 if ( tag == LBER_DEFAULT ) {
452 /* store my result */
455 res.ca[n] = bv.bv_val;
461 bvp = ber_memalloc_x( sizeof( struct berval ),
464 ber_memfree_x( bv.bv_val, ber->ber_memctx );
471 *(struct berval *)(res.bo + tot_size) = bv;
479 if (b->choice != BvOff) { /* BvOff does not have LBER_BV_ALLOC set */
483 ber_memfree_x(res.ca[n], ber->ber_memctx);
486 ber_memfree_x(res.ba[n].bv_val, ber->ber_memctx);
489 ber_memfree_x(res.bv[n]->bv_val, ber->ber_memctx);
490 ber_memfree_x(res.bv[n], ber->ber_memctx);
497 ber_memfree_x(b->result, ber->ber_memctx);
503 ber_get_stringbv( BerElement *ber, struct berval *bv, int option )
508 tag = ber_skip_element( ber, bv );
509 if ( tag == LBER_DEFAULT ||
510 (( option & LBER_BV_STRING ) &&
511 bv->bv_len && memchr( bv->bv_val, 0, bv->bv_len - 1 )))
518 if ( option & LBER_BV_ALLOC ) {
519 bv->bv_val = (char *) ber_memalloc_x( bv->bv_len + 1,
521 if ( bv->bv_val == NULL ) {
525 if ( bv->bv_len != 0 ) {
526 memcpy( bv->bv_val, data, bv->bv_len );
530 if ( !( option & LBER_BV_NOTERM ))
531 data[bv->bv_len] = '\0';
537 ber_get_stringbv_null( BerElement *ber, struct berval *bv, int option )
542 tag = ber_skip_element( ber, bv );
543 if ( tag == LBER_DEFAULT || bv->bv_len == 0 ) {
548 if (( option & LBER_BV_STRING ) &&
549 memchr( bv->bv_val, 0, bv->bv_len - 1 ))
556 if ( option & LBER_BV_ALLOC ) {
557 bv->bv_val = (char *) ber_memalloc_x( bv->bv_len + 1,
559 if ( bv->bv_val == NULL ) {
563 memcpy( bv->bv_val, data, bv->bv_len );
566 if ( !( option & LBER_BV_NOTERM ))
567 data[bv->bv_len] = '\0';
573 ber_get_stringa( BerElement *ber, char **buf )
578 assert( buf != NULL );
580 tag = ber_get_stringbv( ber, &bv, LBER_BV_ALLOC | LBER_BV_STRING );
587 ber_get_stringa_null( BerElement *ber, char **buf )
592 assert( buf != NULL );
594 tag = ber_get_stringbv_null( ber, &bv, LBER_BV_ALLOC | LBER_BV_STRING );
601 ber_get_stringal( BerElement *ber, struct berval **bv )
605 assert( ber != NULL );
606 assert( bv != NULL );
608 *bv = (struct berval *) ber_memalloc_x( sizeof(struct berval),
614 tag = ber_get_stringbv( ber, *bv, LBER_BV_ALLOC );
615 if ( tag == LBER_DEFAULT ) {
616 ber_memfree_x( *bv, ber->ber_memctx );
630 unsigned char unusedbits;
632 assert( buf != NULL );
633 assert( blen != NULL );
635 if ( (tag = ber_skip_element( ber, &data )) == LBER_DEFAULT ) {
639 if ( --data.bv_len > (ber_len_t)-1 / 8 ) {
642 unusedbits = *(unsigned char *) data.bv_val++;
643 if ( unusedbits > 7 ) {
647 if ( memchr( data.bv_val, 0, data.bv_len )) {
651 *buf = (char *) ber_memalloc_x( data.bv_len, ber->ber_memctx );
652 if ( *buf == NULL ) {
655 memcpy( *buf, data.bv_val, data.bv_len );
657 *blen = data.bv_len * 8 - unusedbits;
666 ber_get_null( BerElement *ber )
669 ber_tag_t tag = ber_skip_tag( ber, &len );
671 return( len == 0 ? tag : LBER_DEFAULT );
679 return ber_get_int( ber, boolval );
688 assert( last != NULL );
690 /* skip the sequence header, use the len to mark where to stop */
691 if ( ber_skip_tag( ber, len ) == LBER_DEFAULT ) {
696 *last = ber->ber_ptr + *len;
702 return ber_peek_tag( ber, len );
709 LDAP_CONST char *last )
711 assert( ber != NULL );
712 assert( last != NULL );
713 assert( LBER_VALID( ber ) );
715 if ( ber->ber_ptr >= last ) {
719 return ber_peek_tag( ber, len );
724 ber_scanf ( BerElement *ber,
725 LDAP_CONST char *fmt,
729 LDAP_CONST char *fmt_reset;
730 char *s, **ss, ***sss;
731 struct berval data, *bval, **bvp, ***bvpp;
740 assert( ber != NULL );
741 assert( fmt != NULL );
742 assert( LBER_VALID( ber ) );
746 if ( ber->ber_debug & (LDAP_DEBUG_TRACE|LDAP_DEBUG_BER)) {
747 ber_log_printf( LDAP_DEBUG_TRACE, ber->ber_debug,
748 "ber_scanf fmt (%s) ber:\n", fmt );
749 ber_log_dump( LDAP_DEBUG_BER, ber->ber_debug, ber, 1 );
752 for ( rc = 0; *fmt && rc != LBER_DEFAULT; fmt++ ) {
753 /* When this is modified, remember to update
754 * the error-cleanup code below accordingly. */
756 case '!': { /* Hook */
757 BERDecodeCallback *f;
760 f = va_arg( ap, BERDecodeCallback * );
761 p = va_arg( ap, void * );
763 rc = (*f)( ber, p, 0 );
766 case 'a': /* octet string - allocate storage as needed */
767 ss = va_arg( ap, char ** );
768 rc = ber_get_stringa( ber, ss );
771 case 'A': /* octet string - allocate storage as needed,
772 * but return NULL if len == 0 */
773 ss = va_arg( ap, char ** );
774 rc = ber_get_stringa_null( ber, ss );
777 case 'b': /* boolean */
778 i = va_arg( ap, ber_int_t * );
779 rc = ber_get_boolean( ber, i );
782 case 'B': /* bit string - allocate storage as needed */
783 ss = va_arg( ap, char ** );
784 l = va_arg( ap, ber_len_t * ); /* for length, in bits */
785 rc = ber_get_bitstringa( ber, ss, l );
788 case 'e': /* enumerated */
789 case 'i': /* integer */
790 i = va_arg( ap, ber_int_t * );
791 rc = ber_get_int( ber, i );
794 case 'l': /* length of next item */
795 l = va_arg( ap, ber_len_t * );
796 rc = ber_peek_tag( ber, l );
799 case 'm': /* octet string in berval, in-place */
800 bval = va_arg( ap, struct berval * );
801 rc = ber_get_stringbv( ber, bval, 0 );
804 case 'M': /* bvoffarray - must include address of
805 * a record len, and record offset.
806 * number of records will be returned thru
807 * len ptr on finish. parsed in-place.
810 bgbvr cookie = { BvOff, 0 };
811 bvp = va_arg( ap, struct berval ** );
812 l = va_arg( ap, ber_len_t * );
814 cookie.off = va_arg( ap, ber_len_t );
815 rc = ber_get_stringbvl( ber, &cookie );
816 *bvp = cookie.result;
822 rc = ber_get_null( ber );
825 case 'o': /* octet string in a supplied berval */
826 bval = va_arg( ap, struct berval * );
827 rc = ber_get_stringbv( ber, bval, LBER_BV_ALLOC );
830 case 'O': /* octet string - allocate & include length */
831 bvp = va_arg( ap, struct berval ** );
832 rc = ber_get_stringal( ber, bvp );
835 case 's': /* octet string - in a buffer */
836 s = va_arg( ap, char * );
837 l = va_arg( ap, ber_len_t * );
838 rc = ber_get_stringb( ber, s, l );
841 case 't': /* tag of next item */
842 t = va_arg( ap, ber_tag_t * );
843 *t = rc = ber_peek_tag( ber, &len );
846 case 'T': /* skip tag of next item */
847 t = va_arg( ap, ber_tag_t * );
848 *t = rc = ber_skip_tag( ber, &len );
851 case 'v': /* sequence of strings */
854 ChArray, LBER_BV_ALLOC | LBER_BV_STRING, sizeof( char * )
856 rc = ber_get_stringbvl( ber, &cookie );
857 *(va_arg( ap, char *** )) = cookie.result;
861 case 'V': /* sequence of strings + lengths */
864 BvVec, LBER_BV_ALLOC, sizeof( struct berval * )
866 rc = ber_get_stringbvl( ber, &cookie );
867 *(va_arg( ap, struct berval *** )) = cookie.result;
871 case 'W': /* bvarray */
874 BvArray, LBER_BV_ALLOC, sizeof( struct berval )
876 rc = ber_get_stringbvl( ber, &cookie );
877 *(va_arg( ap, struct berval ** )) = cookie.result;
881 case 'x': /* skip the next element - whatever it is */
882 rc = ber_skip_element( ber, &data );
885 case '{': /* begin sequence */
886 case '[': /* begin set */
888 case 'v': case 'V': case 'W': case 'M':
891 rc = ber_skip_tag( ber, &len );
896 case '}': /* end sequence */
897 case ']': /* end set */
901 if( ber->ber_debug ) {
902 ber_log_printf( LDAP_DEBUG_ANY, ber->ber_debug,
903 "ber_scanf: unknown fmt %c\n", *fmt );
912 if ( rc == LBER_DEFAULT ) {
914 * Error. Reclaim malloced memory that was given to the caller.
915 * Set allocated pointers to NULL, "data length" outvalues to 0.
919 for ( ; fmt_reset < fmt; fmt_reset++ ) {
920 switch ( *fmt_reset ) {
921 case '!': { /* Hook */
922 BERDecodeCallback *f;
925 f = va_arg( ap, BERDecodeCallback * );
926 p = va_arg( ap, void * );
928 (void) (*f)( ber, p, 1 );
931 case 'a': /* octet string - allocate storage as needed */
933 ss = va_arg( ap, char ** );
934 ber_memfree_x( *ss, ber->ber_memctx );
938 case 'b': /* boolean */
939 case 'e': /* enumerated */
940 case 'i': /* integer */
941 (void) va_arg( ap, ber_int_t * );
944 case 'l': /* length of next item */
945 *(va_arg( ap, ber_len_t * )) = 0;
948 case 'm': /* berval in-place */
949 bval = va_arg( ap, struct berval * );
953 case 'M': /* BVoff array in-place */
954 bvp = va_arg( ap, struct berval ** );
955 ber_memfree_x( *bvp, ber->ber_memctx );
957 *(va_arg( ap, ber_len_t * )) = 0;
958 (void) va_arg( ap, ber_len_t );
961 case 'o': /* octet string in a supplied berval */
962 bval = va_arg( ap, struct berval * );
963 ber_memfree_x( bval->bv_val, ber->ber_memctx );
967 case 'O': /* octet string - allocate & include length */
968 bvp = va_arg( ap, struct berval ** );
969 ber_bvfree_x( *bvp, ber->ber_memctx );
973 case 's': /* octet string - in a buffer */
974 (void) va_arg( ap, char * );
975 *(va_arg( ap, ber_len_t * )) = 0;
978 case 't': /* tag of next item */
979 case 'T': /* skip tag of next item */
980 (void) va_arg( ap, ber_tag_t * );
983 case 'B': /* bit string - allocate storage as needed */
984 ss = va_arg( ap, char ** );
985 ber_memfree_x( *ss, ber->ber_memctx );
987 *(va_arg( ap, ber_len_t * )) = 0; /* for length, in bits */
990 case 'v': /* sequence of strings */
991 sss = va_arg( ap, char *** );
992 ber_memvfree_x( (void **) *sss, ber->ber_memctx );
996 case 'V': /* sequence of strings + lengths */
997 bvpp = va_arg( ap, struct berval *** );
998 ber_bvecfree_x( *bvpp, ber->ber_memctx );
1002 case 'W': /* BerVarray */
1003 bvp = va_arg( ap, struct berval ** );
1004 ber_bvarray_free_x( *bvp, ber->ber_memctx );
1008 case 'n': /* null */
1009 case 'x': /* skip the next element - whatever it is */
1010 case '{': /* begin sequence */
1011 case '[': /* begin set */
1012 case '}': /* end sequence */
1013 case ']': /* end set */
1017 /* format should be good */