/* decode.c - ber input decoding routines */ /* $OpenLDAP: pkg/ldap/libraries/liblber/decode.c,v 1.101.2.4 2007/01/02 21:43:48 kurt Exp $ */ /* This work is part of OpenLDAP Software . * * Copyright 1998-2007 The OpenLDAP Foundation. * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted only as authorized by the OpenLDAP * Public License. * * A copy of this license is available in the file LICENSE in the * top-level directory of the distribution or, alternatively, at * . */ /* Portions Copyright (c) 1990 Regents of the University of Michigan. * All rights reserved. * * Redistribution and use in source and binary forms are permitted * provided that this notice is preserved and that due credit is given * to the University of Michigan at Ann Arbor. The name of the University * may not be used to endorse or promote products derived from this * software without specific prior written permission. This software * is provided ``as is'' without express or implied warranty. */ /* ACKNOWLEDGEMENTS: * This work was originally developed by the University of Michigan * (as part of U-MICH LDAP). */ #include "portable.h" #include #include #include #include #include #include "lber-int.h" static ber_len_t ber_getnint LDAP_P(( BerElement *ber, ber_int_t *num, ber_len_t len )); /* return the tag - LBER_DEFAULT returned means trouble */ ber_tag_t ber_get_tag( BerElement *ber ) { unsigned char xbyte; ber_tag_t tag; unsigned int i; assert( ber != NULL ); assert( LBER_VALID( ber ) ); if ( ber_pvt_ber_remaining( ber ) < 1 ) { return LBER_DEFAULT; } if ( ber->ber_ptr == ber->ber_buf ) { tag = *(unsigned char *)ber->ber_ptr; } else { tag = ber->ber_tag; } ber->ber_ptr++; if ( (tag & LBER_BIG_TAG_MASK) != LBER_BIG_TAG_MASK ) { return tag; } for ( i = 1; i < sizeof(ber_tag_t); i++ ) { if ( ber_read( ber, (char *) &xbyte, 1 ) != 1 ) { return LBER_DEFAULT; } tag <<= 8; tag |= 0x00ffUL & (ber_tag_t) xbyte; if ( ! (xbyte & LBER_MORE_TAG_MASK) ) { break; } } /* tag too big! */ if ( i == sizeof(ber_tag_t) ) { return LBER_DEFAULT; } return tag; } ber_tag_t ber_skip_tag( BerElement *ber, ber_len_t *len ) { ber_tag_t tag; unsigned char lc; ber_len_t i, noctets; unsigned char netlen[sizeof(ber_len_t)]; assert( ber != NULL ); assert( len != NULL ); assert( LBER_VALID( ber ) ); /* * Any ber element looks like this: tag length contents. * Assuming everything's ok, we return the tag byte (we * can assume a single byte), and return the length in len. * * Assumptions: * 1) definite lengths * 2) primitive encodings used whenever possible */ *len = 0; /* * First, we read the tag. */ if ( (tag = ber_get_tag( ber )) == LBER_DEFAULT ) { return LBER_DEFAULT; } /* * Next, read the length. The first byte contains the length of * the length. If bit 8 is set, the length is the long form, * otherwise it's the short form. We don't allow a length that's * greater than what we can hold in a ber_len_t. */ if ( ber_read( ber, (char *) &lc, 1 ) != 1 ) { return LBER_DEFAULT; } if ( lc & 0x80U ) { noctets = (lc & 0x7fU); if ( noctets > sizeof(ber_len_t) ) { return LBER_DEFAULT; } if( (unsigned) ber_read( ber, (char *) netlen, noctets ) != noctets ) { return LBER_DEFAULT; } for( i = 0; i < noctets; i++ ) { *len <<= 8; *len |= netlen[i]; } } else { *len = lc; } /* BER element should have enough data left */ if( *len > (ber_len_t) ber_pvt_ber_remaining( ber ) ) { return LBER_DEFAULT; } ber->ber_tag = *(unsigned char *)ber->ber_ptr; return tag; } ber_tag_t ber_peek_tag( BerElement *ber, ber_len_t *len ) { /* * This implementation assumes ber_skip_tag() only * modifies ber_ptr field of the BerElement. */ char *save; ber_tag_t tag, old; old = ber->ber_tag; save = ber->ber_ptr; tag = ber_skip_tag( ber, len ); ber->ber_ptr = save; ber->ber_tag = old; return tag; } static ber_len_t ber_getnint( BerElement *ber, ber_int_t *num, ber_len_t len ) { unsigned char buf[sizeof(ber_int_t)]; assert( ber != NULL ); assert( num != NULL ); assert( LBER_VALID( ber ) ); /* * The tag and length have already been stripped off. We should * be sitting right before len bytes of 2's complement integer, * ready to be read straight into an int. We may have to sign * extend after we read it in. */ if ( len > sizeof(ber_int_t) ) { return -1; } /* read into the low-order bytes of our buffer */ if ( (ber_len_t) ber_read( ber, (char *) buf, len ) != len ) { return -1; } if( len ) { /* sign extend if necessary */ ber_len_t i; ber_int_t netnum = 0x80 & buf[0] ? -1 : 0; /* shift in the bytes */ for( i=0 ; iber_tag = *(unsigned char *)ber->ber_ptr; return len; } ber_tag_t ber_get_int( BerElement *ber, ber_int_t *num ) { ber_tag_t tag; ber_len_t len; assert( ber != NULL ); assert( LBER_VALID( ber ) ); if ( (tag = ber_skip_tag( ber, &len )) == LBER_DEFAULT ) { return LBER_DEFAULT; } if ( ber_getnint( ber, num, len ) != len ) { return LBER_DEFAULT; } return tag; } ber_tag_t ber_get_enum( BerElement *ber, ber_int_t *num ) { return ber_get_int( ber, num ); } ber_tag_t ber_get_stringb( BerElement *ber, char *buf, ber_len_t *len ) { ber_len_t datalen; ber_tag_t tag; assert( ber != NULL ); assert( LBER_VALID( ber ) ); if ( (tag = ber_skip_tag( ber, &datalen )) == LBER_DEFAULT ) { return LBER_DEFAULT; } /* must fit within allocated space with termination */ if ( datalen >= *len ) { return LBER_DEFAULT; } if ( (ber_len_t) ber_read( ber, buf, datalen ) != datalen ) { return LBER_DEFAULT; } ber->ber_tag = *(unsigned char *)ber->ber_ptr; buf[datalen] = '\0'; *len = datalen; return tag; } /* Definitions for get_string vector * * ChArray, BvArray, and BvVec are self-explanatory. * BvOff is a struct berval embedded in an array of larger structures * of siz bytes at off bytes from the beginning of the struct. */ enum bgbvc { ChArray, BvArray, BvVec, BvOff }; /* Use this single cookie for state, to keep actual * stack use to the absolute minimum. */ typedef struct bgbvr { enum bgbvc choice; BerElement *ber; int alloc; ber_len_t siz; ber_len_t off; union { char ***c; BerVarray *ba; struct berval ***bv; } res; } bgbvr; static ber_tag_t ber_get_stringbvl( bgbvr *b, ber_len_t *rlen ) { int i = 0, n; ber_tag_t tag; ber_len_t len; char *last, *orig; struct berval bv, *bvp = NULL; /* For rewinding, just like ber_peek_tag() */ orig = b->ber->ber_ptr; tag = b->ber->ber_tag; if ( ber_first_element( b->ber, &len, &last ) != LBER_DEFAULT ) { for ( ; b->ber->ber_ptr < last; i++ ) { if (ber_skip_tag( b->ber, &len ) == LBER_DEFAULT) break; b->ber->ber_ptr += len; b->ber->ber_tag = *(unsigned char *)b->ber->ber_ptr; } } if ( rlen ) *rlen = i; if ( i == 0 ) { *b->res.c = NULL; return 0; } n = i; /* Allocate the result vector */ switch (b->choice) { case ChArray: *b->res.c = ber_memalloc_x( (n+1)*sizeof( char * ), b->ber->ber_memctx); if ( *b->res.c == NULL ) return LBER_DEFAULT; (*b->res.c)[n] = NULL; break; case BvArray: *b->res.ba = ber_memalloc_x( (n+1)*sizeof( struct berval ), b->ber->ber_memctx); if ( *b->res.ba == NULL ) return LBER_DEFAULT; (*b->res.ba)[n].bv_val = NULL; break; case BvVec: *b->res.bv = ber_memalloc_x( (n+1)*sizeof( struct berval *), b->ber->ber_memctx); if ( *b->res.bv == NULL ) return LBER_DEFAULT; (*b->res.bv)[n] = NULL; break; case BvOff: *b->res.ba = ber_memalloc_x( (n+1) * b->siz, b->ber->ber_memctx ); if ( *b->res.ba == NULL ) return LBER_DEFAULT; ((struct berval *)((long)(*b->res.ba) + n*b->siz + b->off))->bv_val = NULL; break; } b->ber->ber_ptr = orig; b->ber->ber_tag = tag; ber_skip_tag( b->ber, &len ); for (n=0; nber, &len, last ); if ( ber_get_stringbv( b->ber, &bv, b->alloc ) == LBER_DEFAULT ) { goto nomem; } /* store my result */ switch (b->choice) { case ChArray: (*b->res.c)[n] = bv.bv_val; break; case BvArray: (*b->res.ba)[n] = bv; break; case BvVec: bvp = ber_memalloc_x( sizeof( struct berval ), b->ber->ber_memctx); if ( !bvp ) { LBER_FREE(bv.bv_val); goto nomem; } (*b->res.bv)[n] = bvp; *bvp = bv; break; case BvOff: *(BerVarray)((long)(*b->res.ba)+n*b->siz+b->off) = bv; break; } } return tag; nomem: if (b->alloc || b->choice == BvVec) { for (--n; n>=0; n--) { switch(b->choice) { case ChArray: LBER_FREE((*b->res.c)[n]); break; case BvArray: LBER_FREE((*b->res.ba)[n].bv_val); break; case BvVec: LBER_FREE((*b->res.bv)[n]->bv_val); LBER_FREE((*b->res.bv)[n]); break; default: break; } } } LBER_FREE(*b->res.c); *b->res.c = NULL; return LBER_DEFAULT; } ber_tag_t ber_get_stringbv( BerElement *ber, struct berval *bv, int alloc ) { ber_tag_t tag; assert( ber != NULL ); assert( bv != NULL ); assert( LBER_VALID( ber ) ); if ( (tag = ber_skip_tag( ber, &bv->bv_len )) == LBER_DEFAULT ) { bv->bv_val = NULL; return LBER_DEFAULT; } if ( (ber_len_t) ber_pvt_ber_remaining( ber ) < bv->bv_len ) { return LBER_DEFAULT; } if ( alloc ) { bv->bv_val = (char *) ber_memalloc_x( bv->bv_len + 1, ber->ber_memctx ); if ( bv->bv_val == NULL ) { return LBER_DEFAULT; } if ( bv->bv_len > 0 && (ber_len_t) ber_read( ber, bv->bv_val, bv->bv_len ) != bv->bv_len ) { LBER_FREE( bv->bv_val ); bv->bv_val = NULL; return LBER_DEFAULT; } } else { bv->bv_val = ber->ber_ptr; ber->ber_ptr += bv->bv_len; } ber->ber_tag = *(unsigned char *)ber->ber_ptr; bv->bv_val[bv->bv_len] = '\0'; return tag; } #ifdef LDAP_NULL_IS_NULL ber_tag_t ber_get_stringbv_null( BerElement *ber, struct berval *bv, int alloc ) { ber_tag_t tag; assert( ber != NULL ); assert( bv != NULL ); assert( LBER_VALID( ber ) ); if ( (tag = ber_skip_tag( ber, &bv->bv_len )) == LBER_DEFAULT ) { bv->bv_val = NULL; return LBER_DEFAULT; } if ( (ber_len_t) ber_pvt_ber_remaining( ber ) < bv->bv_len ) { return LBER_DEFAULT; } if ( bv->bv_len == 0 ) { bv->bv_val = NULL; ber->ber_tag = *(unsigned char *)ber->ber_ptr; return tag; } if ( alloc ) { bv->bv_val = (char *) ber_memalloc_x( bv->bv_len + 1, ber->ber_memctx ); if ( bv->bv_val == NULL ) { return LBER_DEFAULT; } if ( bv->bv_len > 0 && (ber_len_t) ber_read( ber, bv->bv_val, bv->bv_len ) != bv->bv_len ) { LBER_FREE( bv->bv_val ); bv->bv_val = NULL; return LBER_DEFAULT; } } else { bv->bv_val = ber->ber_ptr; ber->ber_ptr += bv->bv_len; } ber->ber_tag = *(unsigned char *)ber->ber_ptr; bv->bv_val[bv->bv_len] = '\0'; return tag; } #endif /* LDAP_NULL_IS_NULL */ ber_tag_t ber_get_stringa( BerElement *ber, char **buf ) { BerValue bv; ber_tag_t tag; assert( buf != NULL ); tag = ber_get_stringbv( ber, &bv, 1 ); *buf = bv.bv_val; return tag; } #ifdef LDAP_NULL_IS_NULL ber_tag_t ber_get_stringa_null( BerElement *ber, char **buf ) { BerValue bv; ber_tag_t tag; assert( buf != NULL ); tag = ber_get_stringbv_null( ber, &bv, 1 ); *buf = bv.bv_val; return tag; } #endif /* LDAP_NULL_IS_NULL */ ber_tag_t ber_get_stringal( BerElement *ber, struct berval **bv ) { ber_tag_t tag; assert( ber != NULL ); assert( bv != NULL ); *bv = (struct berval *) ber_memalloc_x( sizeof(struct berval), ber->ber_memctx ); if ( *bv == NULL ) { return LBER_DEFAULT; } tag = ber_get_stringbv( ber, *bv, 1 ); if ( tag == LBER_DEFAULT ) { LBER_FREE( *bv ); *bv = NULL; } return tag; } ber_tag_t ber_get_bitstringa( BerElement *ber, char **buf, ber_len_t *blen ) { ber_len_t datalen; ber_tag_t tag; unsigned char unusedbits; assert( ber != NULL ); assert( buf != NULL ); assert( blen != NULL ); assert( LBER_VALID( ber ) ); if ( (tag = ber_skip_tag( ber, &datalen )) == LBER_DEFAULT ) { *buf = NULL; return LBER_DEFAULT; } --datalen; *buf = (char *) ber_memalloc_x( datalen, ber->ber_memctx ); if ( *buf == NULL ) { return LBER_DEFAULT; } if ( ber_read( ber, (char *)&unusedbits, 1 ) != 1 ) { LBER_FREE( buf ); *buf = NULL; return LBER_DEFAULT; } if ( (ber_len_t) ber_read( ber, *buf, datalen ) != datalen ) { LBER_FREE( buf ); *buf = NULL; return LBER_DEFAULT; } ber->ber_tag = *(unsigned char *)ber->ber_ptr; *blen = datalen * 8 - unusedbits; return tag; } ber_tag_t ber_get_null( BerElement *ber ) { ber_len_t len; ber_tag_t tag; assert( ber != NULL ); assert( LBER_VALID( ber ) ); if ( (tag = ber_skip_tag( ber, &len )) == LBER_DEFAULT ) { return LBER_DEFAULT; } if ( len != 0 ) { return LBER_DEFAULT; } ber->ber_tag = *(unsigned char *)ber->ber_ptr; return( tag ); } ber_tag_t ber_get_boolean( BerElement *ber, ber_int_t *boolval ) { ber_int_t longbool; ber_tag_t rc; assert( ber != NULL ); assert( boolval != NULL ); assert( LBER_VALID( ber ) ); rc = ber_get_int( ber, &longbool ); *boolval = longbool; return rc; } ber_tag_t ber_first_element( BerElement *ber, ber_len_t *len, char **last ) { assert( ber != NULL ); assert( len != NULL ); assert( last != NULL ); /* skip the sequence header, use the len to mark where to stop */ if ( ber_skip_tag( ber, len ) == LBER_DEFAULT ) { *last = NULL; return LBER_DEFAULT; } ber->ber_tag = *(unsigned char *)ber->ber_ptr; *last = ber->ber_ptr + *len; if ( *last == ber->ber_ptr ) { return LBER_DEFAULT; } return ber_peek_tag( ber, len ); } ber_tag_t ber_next_element( BerElement *ber, ber_len_t *len, LDAP_CONST char *last ) { assert( ber != NULL ); assert( len != NULL ); assert( last != NULL ); assert( LBER_VALID( ber ) ); if ( ber->ber_ptr >= last ) { return LBER_DEFAULT; } return ber_peek_tag( ber, len ); } /* VARARGS */ ber_tag_t ber_scanf ( BerElement *ber, LDAP_CONST char *fmt, ... ) { va_list ap; LDAP_CONST char *fmt_reset; char *s, **ss; struct berval **bvp, *bval; ber_int_t *i; ber_len_t *l; ber_tag_t *t; ber_tag_t rc; ber_len_t len; va_start( ap, fmt ); assert( ber != NULL ); assert( fmt != NULL ); assert( LBER_VALID( ber ) ); fmt_reset = fmt; ber_log_printf( LDAP_DEBUG_TRACE, ber->ber_debug, "ber_scanf fmt (%s) ber:\n", fmt ); ber_log_dump( LDAP_DEBUG_BER, ber->ber_debug, ber, 1 ); for ( rc = 0; *fmt && rc != LBER_DEFAULT; fmt++ ) { /* When this is modified, remember to update * the error-cleanup code below accordingly. */ switch ( *fmt ) { case '!': { /* Hook */ BERDecodeCallback *f; void *p; f = va_arg( ap, BERDecodeCallback * ); p = va_arg( ap, void * ); rc = (*f)( ber, p, 0 ); } break; case 'a': /* octet string - allocate storage as needed */ ss = va_arg( ap, char ** ); rc = ber_get_stringa( ber, ss ); break; #ifdef LDAP_NULL_IS_NULL case 'A': /* octet string - allocate storage as needed, * but return NULL if len == 0 */ ss = va_arg( ap, char ** ); rc = ber_get_stringa_null( ber, ss ); break; #endif /* LDAP_NULL_IS_NULL */ case 'b': /* boolean */ i = va_arg( ap, ber_int_t * ); rc = ber_get_boolean( ber, i ); break; case 'B': /* bit string - allocate storage as needed */ ss = va_arg( ap, char ** ); l = va_arg( ap, ber_len_t * ); /* for length, in bits */ rc = ber_get_bitstringa( ber, ss, l ); break; case 'e': /* enumerated */ case 'i': /* int */ i = va_arg( ap, ber_int_t * ); rc = ber_get_int( ber, i ); break; case 'l': /* length of next item */ l = va_arg( ap, ber_len_t * ); rc = ber_peek_tag( ber, l ); break; case 'm': /* octet string in berval, in-place */ bval = va_arg( ap, struct berval * ); rc = ber_get_stringbv( ber, bval, 0 ); break; case 'M': /* bvoffarray - must include address of * a record len, and record offset. * number of records will be returned thru * len ptr on finish. parsed in-place. */ { bgbvr cookie = { BvOff }; cookie.ber = ber; cookie.res.ba = va_arg( ap, struct berval ** ); cookie.alloc = 0; l = va_arg( ap, ber_len_t * ); cookie.siz = *l; cookie.off = va_arg( ap, ber_len_t ); rc = ber_get_stringbvl( &cookie, l ); break; } case 'n': /* null */ rc = ber_get_null( ber ); break; case 'o': /* octet string in a supplied berval */ bval = va_arg( ap, struct berval * ); rc = ber_get_stringbv( ber, bval, 1 ); break; case 'O': /* octet string - allocate & include length */ bvp = va_arg( ap, struct berval ** ); rc = ber_get_stringal( ber, bvp ); break; case 's': /* octet string - in a buffer */ s = va_arg( ap, char * ); l = va_arg( ap, ber_len_t * ); rc = ber_get_stringb( ber, s, l ); break; case 't': /* tag of next item */ t = va_arg( ap, ber_tag_t * ); *t = rc = ber_peek_tag( ber, &len ); break; case 'T': /* skip tag of next item */ t = va_arg( ap, ber_tag_t * ); *t = rc = ber_skip_tag( ber, &len ); break; case 'v': /* sequence of strings */ { bgbvr cookie = { ChArray }; cookie.ber = ber; cookie.res.c = va_arg( ap, char *** ); cookie.alloc = 1; rc = ber_get_stringbvl( &cookie, NULL ); break; } case 'V': /* sequence of strings + lengths */ { bgbvr cookie = { BvVec }; cookie.ber = ber; cookie.res.bv = va_arg( ap, struct berval *** ); cookie.alloc = 1; rc = ber_get_stringbvl( &cookie, NULL ); break; } case 'W': /* bvarray */ { bgbvr cookie = { BvArray }; cookie.ber = ber; cookie.res.ba = va_arg( ap, struct berval ** ); cookie.alloc = 1; rc = ber_get_stringbvl( &cookie, NULL ); break; } case 'x': /* skip the next element - whatever it is */ if ( (rc = ber_skip_tag( ber, &len )) == LBER_DEFAULT ) break; ber->ber_ptr += len; ber->ber_tag = *(unsigned char *)ber->ber_ptr; break; case '{': /* begin sequence */ case '[': /* begin set */ if ( *(fmt + 1) != 'v' && *(fmt + 1) != 'V' && *(fmt + 1) != 'W' && *(fmt + 1) != 'M' ) rc = ber_skip_tag( ber, &len ); break; case '}': /* end sequence */ case ']': /* end set */ break; default: if( ber->ber_debug ) { ber_log_printf( LDAP_DEBUG_ANY, ber->ber_debug, "ber_scanf: unknown fmt %c\n", *fmt ); } rc = LBER_DEFAULT; break; } } va_end( ap ); if ( rc == LBER_DEFAULT ) { /* * Error. Reclaim malloced memory that was given to the caller. * Set allocated pointers to NULL, "data length" outvalues to 0. */ va_start( ap, fmt ); for ( ; fmt_reset < fmt; fmt_reset++ ) { switch ( *fmt_reset ) { case '!': { /* Hook */ BERDecodeCallback *f; void *p; f = va_arg( ap, BERDecodeCallback * ); p = va_arg( ap, void * ); (void) (*f)( ber, p, 1 ); } break; case 'a': /* octet string - allocate storage as needed */ #ifdef LDAP_NULL_IS_NULL case 'A': #endif /* LDAP_NULL_IS_NULL */ ss = va_arg( ap, char ** ); if ( *ss ) { LBER_FREE( *ss ); *ss = NULL; } break; case 'b': /* boolean */ case 'e': /* enumerated */ case 'i': /* int */ (void) va_arg( ap, int * ); break; case 'l': /* length of next item */ (void) va_arg( ap, ber_len_t * ); break; case 'o': /* octet string in a supplied berval */ bval = va_arg( ap, struct berval * ); if ( bval->bv_val != NULL ) { LBER_FREE( bval->bv_val ); bval->bv_val = NULL; } bval->bv_len = 0; break; case 'O': /* octet string - allocate & include length */ bvp = va_arg( ap, struct berval ** ); if ( *bvp ) { ber_bvfree( *bvp ); *bvp = NULL; } break; case 's': /* octet string - in a buffer */ (void) va_arg( ap, char * ); (void) va_arg( ap, ber_len_t * ); break; case 't': /* tag of next item */ case 'T': /* skip tag of next item */ (void) va_arg( ap, ber_tag_t * ); break; case 'B': /* bit string - allocate storage as needed */ ss = va_arg( ap, char ** ); if ( *ss ) { LBER_FREE( *ss ); *ss = NULL; } *(va_arg( ap, ber_len_t * )) = 0; /* for length, in bits */ break; case 'm': /* berval in-place */ case 'M': /* BVoff array in-place */ case 'n': /* null */ case 'v': /* sequence of strings */ case 'V': /* sequence of strings + lengths */ case 'W': /* BerVarray */ case 'x': /* skip the next element - whatever it is */ case '{': /* begin sequence */ case '[': /* begin set */ case '}': /* end sequence */ case ']': /* end set */ break; default: /* format should be good */ assert( 0 ); } } va_end( ap ); } return rc; }