Keep ldap_first/next_attribute from running past end of attributes.

Likely other sequences need this attention.

diff --git a/libraries/libldap/getattr.c b/libraries/libldap/getattr.c
index 79fe0a4ad03a3ef2c77616a1e82c0ff294e3ae5f..9b4f2fe06c2cb171e69c2e526062e7cb42699b67 100644 (file)
--- a/libraries/libldap/getattr.c
+++ b/libraries/libldap/getattr.c
@@ -22,46 +22,76 @@
 #include "ldap-int.h"
 
 char *
-ldap_first_attribute( LDAP *ld, LDAPMessage *entry, BerElement **ber )
+ldap_first_attribute( LDAP *ld, LDAPMessage *entry, BerElement **berout )
 {
+       ber_tag_t rc;
+       ber_len_t len;
        char *attr;
+       BerElement *ber;
 
        Debug( LDAP_DEBUG_TRACE, "ldap_first_attribute\n", 0, 0, 0 );
 
        assert( ld != NULL );
        assert( LDAP_VALID( ld ) );
        assert( entry != NULL );
-       assert( ber != NULL );
+       assert( berout != NULL );
 
-       if ( (*ber = ldap_alloc_ber_with_options( ld )) == NULL ) {
-               *ber = NULL;
-               return( NULL );
+       ber = ldap_alloc_ber_with_options( ld );
+       if( ber == NULL ) {
+               return NULL;
        }
 
-       **ber = *entry->lm_ber;
+       *ber = *entry->lm_ber;
 
        /* 
-        * Skip past the sequence, dn, sequence of sequence, snarf the
-        * attribute type, and skip the set of values, leaving us
-        * positioned right before the next attribute type/value sequence.
+        * Skip past the sequence, dn, sequence of sequence leaving
+        * us at the first attribute.
         */
 
-       if ( ber_scanf( *ber, "{x{{ax}" /*}}*/, &attr )
-           == LBER_ERROR ) {
+       rc = ber_scanf( ber, "{xl{" /*}}*/, &attr, &len );
+
+       if( rc == LBER_ERROR ) {
                ld->ld_errno = LDAP_DECODING_ERROR;
-               ber_free( *ber, 0 );
-               *ber = NULL;
-               return( NULL );
+               ber_free( ber, 0 );
+               return  NULL;
+       }
+
+#if 0
+       if( len == 0 ) {
+               return NULL;
+       }
+#endif
+       
+       /* set the length to avoid overrun */
+       rc = ber_set_option( ber, LBER_OPT_REMAINING_BYTES, &len );
+
+       if( rc != LBER_OPT_SUCCESS ) {
+               ld->ld_errno = LDAP_LOCAL_ERROR;
+               ber_free( ber, 0 );
+               return NULL;
        }
 
-       return( attr );
+       /* snatch the first attribute */
+       rc = ber_scanf( ber, "{ax}", &attr );
+       if( rc == LBER_ERROR ) {
+               ld->ld_errno = LDAP_DECODING_ERROR;
+               ber_free( ber, 0 );
+               return NULL;
+       }
+
+       *berout = ber;
+       return attr;
 }
 
 /* ARGSUSED */
 char *
 ldap_next_attribute( LDAP *ld, LDAPMessage *entry, BerElement *ber )
 {
+       ber_tag_t rc;
        char *attr;
+#if 0
+       ber_len_t len;
+#endif
 
        Debug( LDAP_DEBUG_TRACE, "ldap_next_attribute\n", 0, 0, 0 );
 
@@ -70,12 +100,23 @@ ldap_next_attribute( LDAP *ld, LDAPMessage *entry, BerElement *ber )
        assert( entry != NULL );
        assert( ber != NULL );
 
+#if 0
+       rc = ber_get_option( ber, LBER_OPT_REMAINING_BYTES, &len );
+       if( rc != LDAP_OPT_SUCCESS ) {
+               ld->ld_errno = LDAP_LOCAL_ERROR;
+               return NULL;
+       }
+
+       /* we're done */
+       if( len == 0 ) return NULL;
+#endif
+
        /* skip sequence, snarf attribute type, skip values */
-       if ( ber_scanf( ber, "{ax}", &attr ) 
-           == LBER_ERROR ) {
+       rc = ber_scanf( ber, "{ax}", &attr ); 
+       if( rc == LBER_ERROR ) {
                ld->ld_errno = LDAP_DECODING_ERROR;
-               return( NULL );
+               return NULL;
        }
 
-       return( attr );
+       return attr;
 }