/* decode.c - ber input decoding routines */ /* $OpenLDAP$ */ /* This work is part of OpenLDAP Software . * * Copyright 1998-2009 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" /* out->bv_len should be the buffer size on input */ int ber_decode_oid( BerValue *in, BerValue *out ) { const unsigned char *der; unsigned long val; unsigned val1; ber_len_t i; char *ptr; assert( in != NULL ); assert( out != NULL ); /* need 4 chars/inbyte + \0 for input={7f 7f 7f...} */ if ( !out->bv_val || (out->bv_len+3)/4 <= in->bv_len ) return -1; ptr = NULL; der = (unsigned char *) in->bv_val; val = 0; for ( i=0; i < in->bv_len; i++ ) { val |= der[i] & 0x7f; if ( !( der[i] & 0x80 )) { if ( ptr == NULL ) { /* Initial "x.y": val=x*40+y, x<=2, y<40 if x<2 */ ptr = out->bv_val; val1 = (val < 80 ? val/40 : 2); val -= val1*40; ptr += sprintf( ptr, "%u", val1 ); } ptr += sprintf( ptr, ".%lu", val ); val = 0; } else if ( val - 1UL < LBER_OID_COMPONENT_MAX >> 7 ) { val <<= 7; } else { /* val would overflow, or is 0 from invalid initial 0x80 octet */ return -1; } } if ( ptr == NULL || val != 0 ) return -1; out->bv_len = ptr - out->bv_val; return 0; } /* Return tag, with *bv = rest of element (starting at length octets) */ static ber_tag_t ber_tag_and_rest( const BerElement *ber, struct berval *bv ) { ber_tag_t tag; ptrdiff_t rest; unsigned char *ptr; assert( ber != NULL ); assert( LBER_VALID( ber ) ); ptr = (unsigned char *) ber->ber_ptr; rest = (unsigned char *) ber->ber_end - ptr; if ( rest <= 0 ) { goto fail; } tag = ber->ber_tag; if ( (char *) ptr == ber->ber_buf ) { tag = *ptr; } ptr++; rest--; if ( (tag & LBER_BIG_TAG_MASK) != LBER_BIG_TAG_MASK ) { goto done; } do { if ( rest <= 0 ) { break; } tag <<= 8; tag |= *ptr++ & 0xffU; rest--; if ( ! (tag & LBER_MORE_TAG_MASK) ) { goto done; } } while ( tag <= (ber_tag_t)-1 / 256 ); fail: /* Error or unsupported tag size */ tag = LBER_DEFAULT; done: bv->bv_len = rest; bv->bv_val = (char *) ptr; return tag; } /* Return the tag - LBER_DEFAULT returned means trouble */ ber_tag_t ber_get_tag( BerElement *ber ) { struct berval bv; ber_tag_t tag = ber_tag_and_rest( ber, &bv ); ber->ber_ptr = bv.bv_val; return tag; } /* Return next element's tag and point *bv at its contents in-place */ ber_tag_t ber_peek_element( const BerElement *ber, struct berval *bv ) { ber_tag_t tag; ber_len_t len, rest; unsigned i; unsigned char *ptr; assert( bv != NULL ); /* * Any ber element looks like this: tag length contents. * Assuming everything's ok, we return the tag, and point * bv at the contents. * * Assumptions: * 1) definite lengths * 2) primitive encodings used whenever possible */ len = 0; /* * First, we read the tag. */ tag = ber_tag_and_rest( ber, bv ); rest = bv->bv_len; ptr = (unsigned char *) bv->bv_val; if ( tag == LBER_DEFAULT || rest == 0 ) { goto fail; } /* * Next, read the length. The first octet determines the length * of the length. If bit 8 is 0, the length is the short form, * otherwise if the octet != 0x80 it's the long form, otherwise * the ber element has the unsupported indefinite-length format. * Lengths that do not fit in a ber_len_t are not accepted. */ len = *ptr++; rest--; if ( len & 0x80U ) { len &= 0x7fU; if ( len - 1U > sizeof(ber_len_t) - 1U || rest < len ) { /* Indefinite-length/too long length/not enough data */ goto fail; } rest -= len; i = len; for( len = *ptr++ & 0xffU; --i; len |= *ptr++ & 0xffU ) { len <<= 8; } } /* BER element should have enough data left */ if( len > rest ) { fail: tag = LBER_DEFAULT; } bv->bv_len = len; bv->bv_val = (char *) ptr; return tag; } /* Move past next element, point *bv at it in-place, and return its tag. * The caller may \0-terminate *bv, as next octet is saved in ber->ber_tag. * Similar to ber_get_stringbv(ber, bv, LBER_BV_NOTERM) except on error. */ ber_tag_t ber_skip_element( BerElement *ber, struct berval *bv ) { ber_tag_t tag = ber_peek_element( ber, bv ); if ( tag != LBER_DEFAULT ) { ber->ber_ptr = bv->bv_val + bv->bv_len; ber->ber_tag = *(unsigned char *) ber->ber_ptr; } return tag; } ber_tag_t ber_peek_tag( BerElement *ber, ber_len_t *len ) { struct berval bv; ber_tag_t tag = ber_peek_element( ber, &bv ); *len = bv.bv_len; return tag; } ber_tag_t ber_skip_tag( BerElement *ber, ber_len_t *lenp ) { struct berval bv; ber_tag_t tag = ber_peek_element( ber, &bv ); ber->ber_ptr = bv.bv_val; ber->ber_tag = *(unsigned char *) ber->ber_ptr; *lenp = bv.bv_len; return tag; } ber_tag_t ber_get_int( BerElement *ber, ber_int_t *num ) { ber_tag_t tag; ber_len_t len; struct berval bv; assert( num != NULL ); tag = ber_skip_element( ber, &bv ); len = bv.bv_len; if ( tag == LBER_DEFAULT || len > sizeof(ber_int_t) ) { return LBER_DEFAULT; } /* parse two's complement integer */ if( len ) { unsigned char *buf = (unsigned char *) bv.bv_val; ber_len_t i; ber_int_t netnum = buf[0] & 0xff; /* sign extend */ netnum = (netnum ^ 0x80) - 0x80; /* shift in the bytes */ for( i = 1; i < len; i++ ) { netnum = (netnum << 8 ) | buf[i]; } *num = netnum; } else { *num = 0; } 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 ) { struct berval bv; ber_tag_t tag; if ( (tag = ber_skip_element( ber, &bv )) == LBER_DEFAULT ) { return LBER_DEFAULT; } /* must fit within allocated space with termination */ if ( bv.bv_len >= *len ) { return LBER_DEFAULT; } memcpy( buf, bv.bv_val, bv.bv_len ); buf[bv.bv_len] = '\0'; *len = bv.bv_len; 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 { const enum bgbvc choice; const int alloc; /* choice == BvOff ? 0 : LBER_ALLOC */ ber_len_t siz; /* input array element size, output count */ ber_len_t off; /* BvOff offset to the struct berval */ void *result; } bgbvr; static ber_tag_t ber_get_stringbvl( BerElement *ber, bgbvr *b ) { int i = 0, n; ber_tag_t tag; ber_len_t tot_size = 0, siz = b->siz; char *last, *orig; struct berval bv, *bvp = NULL; union stringbvl_u { char **ca; /* ChArray */ BerVarray ba; /* BvArray */ struct berval **bv; /* BvVec */ char *bo; /* BvOff */ } res; tag = ber_skip_tag( ber, &bv.bv_len ); if ( tag != LBER_DEFAULT ) { tag = 0; orig = ber->ber_ptr; last = orig + bv.bv_len; for ( ; ber->ber_ptr < last; i++, tot_size += siz ) { if ( ber_skip_element( ber, &bv ) == LBER_DEFAULT ) break; } if ( ber->ber_ptr != last ) { i = 0; tag = LBER_DEFAULT; } ber->ber_ptr = orig; ber->ber_tag = *(unsigned char *) orig; } b->siz = i; if ( i == 0 ) { return tag; } /* Allocate and NULL-terminate the result vector */ b->result = ber_memalloc_x( tot_size + siz, ber->ber_memctx ); if ( b->result == NULL ) { return LBER_DEFAULT; } switch (b->choice) { case ChArray: res.ca = b->result; res.ca[i] = NULL; break; case BvArray: res.ba = b->result; res.ba[i].bv_val = NULL; break; case BvVec: res.bv = b->result; res.bv[i] = NULL; break; case BvOff: res.bo = (char *) b->result + b->off; ((struct berval *) (res.bo + tot_size))->bv_val = NULL; tot_size = 0; break; } n = 0; do { tag = ber_get_stringbv( ber, &bv, b->alloc ); if ( tag == LBER_DEFAULT ) { goto nomem; } /* store my result */ switch (b->choice) { case ChArray: res.ca[n] = bv.bv_val; break; case BvArray: res.ba[n] = bv; break; case BvVec: bvp = ber_memalloc_x( sizeof( struct berval ), ber->ber_memctx ); if ( !bvp ) { ber_memfree_x( bv.bv_val, ber->ber_memctx ); goto nomem; } res.bv[n] = bvp; *bvp = bv; break; case BvOff: *(struct berval *)(res.bo + tot_size) = bv; tot_size += siz; break; } } while (++n < i); return tag; nomem: if (b->choice != BvOff) { /* BvOff does not have b->alloc set */ while (--n >= 0) { switch(b->choice) { case ChArray: ber_memfree_x(res.ca[n], ber->ber_memctx); break; case BvArray: ber_memfree_x(res.ba[n].bv_val, ber->ber_memctx); break; case BvVec: ber_memfree_x(res.bv[n]->bv_val, ber->ber_memctx); ber_memfree_x(res.bv[n], ber->ber_memctx); break; default: break; } } } ber_memfree_x(b->result, ber->ber_memctx); b->result = NULL; return LBER_DEFAULT; } ber_tag_t ber_get_stringbv( BerElement *ber, struct berval *bv, int option ) { ber_tag_t tag; char *data; tag = ber_skip_element( ber, bv ); if ( tag == LBER_DEFAULT ) { bv->bv_val = NULL; return tag; } data = bv->bv_val; if ( option & LBER_BV_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 ) { memcpy( bv->bv_val, data, bv->bv_len ); } data = bv->bv_val; } if ( !( option & LBER_BV_NOTERM )) data[bv->bv_len] = '\0'; return tag; } ber_tag_t ber_get_stringbv_null( BerElement *ber, struct berval *bv, int option ) { ber_tag_t tag; char *data; tag = ber_skip_element( ber, bv ); if ( tag == LBER_DEFAULT || bv->bv_len == 0 ) { bv->bv_val = NULL; return tag; } data = bv->bv_val; if ( option & LBER_BV_ALLOC ) { bv->bv_val = (char *) ber_memalloc_x( bv->bv_len + 1, ber->ber_memctx ); if ( bv->bv_val == NULL ) { return LBER_DEFAULT; } memcpy( bv->bv_val, data, bv->bv_len ); data = bv->bv_val; } if ( !( option & LBER_BV_NOTERM )) data[bv->bv_len] = '\0'; return tag; } 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, LBER_BV_ALLOC ); *buf = bv.bv_val; return tag; } 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, LBER_BV_ALLOC ); *buf = bv.bv_val; return tag; } 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, LBER_BV_ALLOC ); if ( tag == LBER_DEFAULT ) { ber_memfree_x( *bv, ber->ber_memctx ); *bv = NULL; } return tag; } ber_tag_t ber_get_bitstringa( BerElement *ber, char **buf, ber_len_t *blen ) { ber_tag_t tag; struct berval data; unsigned char unusedbits; assert( buf != NULL ); assert( blen != NULL ); if ( (tag = ber_skip_element( ber, &data )) == LBER_DEFAULT ) { goto fail; } if ( --data.bv_len > (ber_len_t)-1 / 8 ) { goto fail; } unusedbits = *(unsigned char *) data.bv_val++; if ( unusedbits > 7 ) { goto fail; } *buf = (char *) ber_memalloc_x( data.bv_len, ber->ber_memctx ); if ( *buf == NULL ) { return LBER_DEFAULT; } memcpy( *buf, data.bv_val, data.bv_len ); *blen = data.bv_len * 8 - unusedbits; return tag; fail: *buf = NULL; return LBER_DEFAULT; } ber_tag_t ber_get_null( BerElement *ber ) { ber_len_t len; ber_tag_t tag = ber_skip_tag( ber, &len ); return( len == 0 ? tag : LBER_DEFAULT ); } ber_tag_t ber_get_boolean( BerElement *ber, ber_int_t *boolval ) { return ber_get_int( ber, boolval ); } ber_tag_t ber_first_element( BerElement *ber, ber_len_t *len, char **last ) { 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; } *last = ber->ber_ptr + *len; if ( *len == 0 ) { 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( 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, ***sss; struct berval data, *bval, **bvp, ***bvpp; 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; if ( ber->ber_debug & (LDAP_DEBUG_TRACE|LDAP_DEBUG_BER)) { 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; 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; 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': /* integer */ 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, 0 }; bvp = va_arg( ap, struct berval ** ); l = va_arg( ap, ber_len_t * ); cookie.siz = *l; cookie.off = va_arg( ap, ber_len_t ); rc = ber_get_stringbvl( ber, &cookie ); *bvp = cookie.result; *l = cookie.siz; 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, LBER_BV_ALLOC ); 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, LBER_BV_ALLOC, sizeof( char * ) }; rc = ber_get_stringbvl( ber, &cookie ); *(va_arg( ap, char *** )) = cookie.result; break; } case 'V': /* sequence of strings + lengths */ { bgbvr cookie = { BvVec, LBER_BV_ALLOC, sizeof( struct berval * ) }; rc = ber_get_stringbvl( ber, &cookie ); *(va_arg( ap, struct berval *** )) = cookie.result; break; } case 'W': /* bvarray */ { bgbvr cookie = { BvArray, LBER_BV_ALLOC, sizeof( struct berval ) }; rc = ber_get_stringbvl( ber, &cookie ); *(va_arg( ap, struct berval ** )) = cookie.result; break; } case 'x': /* skip the next element - whatever it is */ rc = ber_skip_element( ber, &data ); break; case '{': /* begin sequence */ case '[': /* begin set */ switch ( fmt[1] ) { case 'v': case 'V': case 'W': case 'M': break; default: rc = ber_skip_tag( ber, &len ); break; } 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 */ case 'A': ss = va_arg( ap, char ** ); ber_memfree_x( *ss, ber->ber_memctx ); *ss = NULL; break; case 'b': /* boolean */ case 'e': /* enumerated */ case 'i': /* integer */ (void) va_arg( ap, ber_int_t * ); break; case 'l': /* length of next item */ *(va_arg( ap, ber_len_t * )) = 0; break; case 'm': /* berval in-place */ bval = va_arg( ap, struct berval * ); BER_BVZERO( bval ); break; case 'M': /* BVoff array in-place */ bvp = va_arg( ap, struct berval ** ); ber_memfree_x( *bvp, ber->ber_memctx ); *bvp = NULL; *(va_arg( ap, ber_len_t * )) = 0; (void) va_arg( ap, ber_len_t ); break; case 'o': /* octet string in a supplied berval */ bval = va_arg( ap, struct berval * ); ber_memfree_x( bval->bv_val, ber->ber_memctx ); BER_BVZERO( bval ); break; case 'O': /* octet string - allocate & include length */ bvp = va_arg( ap, struct berval ** ); ber_bvfree_x( *bvp, ber->ber_memctx ); *bvp = NULL; break; case 's': /* octet string - in a buffer */ (void) va_arg( ap, char * ); *(va_arg( ap, ber_len_t * )) = 0; 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 ** ); ber_memfree_x( *ss, ber->ber_memctx ); *ss = NULL; *(va_arg( ap, ber_len_t * )) = 0; /* for length, in bits */ break; case 'v': /* sequence of strings */ sss = va_arg( ap, char *** ); ber_memvfree_x( (void **) *sss, ber->ber_memctx ); *sss = NULL; break; case 'V': /* sequence of strings + lengths */ bvpp = va_arg( ap, struct berval *** ); ber_bvecfree_x( *bvpp, ber->ber_memctx ); *bvpp = NULL; break; case 'W': /* BerVarray */ bvp = va_arg( ap, struct berval ** ); ber_bvarray_free_x( *bvp, ber->ber_memctx ); *bvp = NULL; break; case 'n': /* null */ 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; }