/* schema_check.c - routines to enforce schema definitions */
/* $OpenLDAP$ */
/*
 * Copyright 1998-2000 The OpenLDAP Foundation, All Rights Reserved.
 * COPYING RESTRICTIONS APPLY, see COPYRIGHT file
 */

#include "portable.h"

#include <stdio.h>

#include <ac/ctype.h>
#include <ac/string.h>
#include <ac/socket.h>

#include "slap.h"
#include "ldap_pvt.h"

static char * oc_check_required(
	Entry *e,
	ObjectClass *oc,
	struct berval *ocname );

/*
 * Determine the structural object class from a set of OIDs
 */
int structural_class(
	struct berval **ocs,
	struct berval *scbv,
	const char **text,
	char *textbuf, size_t textlen )
{
	int i;
	ObjectClass *oc;
	ObjectClass *sc = NULL;
	int scn = -1;

	*text = "structural_class: internal error";
	scbv->bv_len = 0;

	for( i=0; ocs[i]; i++ ) {
		oc = oc_find( ocs[i]->bv_val );

		if( oc == NULL ) {
			snprintf( textbuf, textlen,
				"unrecongized objectClass '%s'",
				ocs[i]->bv_val );
			*text = textbuf;
			return LDAP_OBJECT_CLASS_VIOLATION;
		}

		if( oc->soc_kind == LDAP_SCHEMA_STRUCTURAL ) {
			if( sc == NULL || is_object_subclass( sc, oc ) ) {
				sc = oc;
				scn = i;

			} else if ( !is_object_subclass( oc, sc ) ) {
				int j;
				ObjectClass *xc = NULL;

				/* find common superior */
				for( j=i+1; ocs[j]; j++ ) {
					xc = oc_find( ocs[j]->bv_val );

					if( xc == NULL ) {
						snprintf( textbuf, textlen,
							"unrecongized objectClass '%s'",
							ocs[i]->bv_val );
						*text = textbuf;
						return LDAP_OBJECT_CLASS_VIOLATION;
					}

					if( xc->soc_kind != LDAP_SCHEMA_STRUCTURAL ) {
						xc = NULL;
						continue;
					}

					if( is_object_subclass( sc, xc ) &&
						is_object_subclass( oc, xc ) )
					{
						/* found common subclass */
						break;
					}

					xc = NULL;
				}

				if( xc == NULL ) {
					/* no common subclass */
					snprintf( textbuf, textlen,
						"invalid structural object class chain (%s/%s)",
						ocs[scn]->bv_val, ocs[i]->bv_val );
					*text = textbuf;
					return LDAP_OBJECT_CLASS_VIOLATION;
				}
			}
		}
	}

	if( sc == NULL ) {
		*text = "no structural object classes provided";
		return LDAP_OBJECT_CLASS_VIOLATION;
	}

	*scbv = *ocs[scn];
	return LDAP_SUCCESS;
}

/*
 * Return structural object class from list of modifications
 */
int mods_structural_class(
	Modifications *mods,
	struct berval *sc,
	const char **text,
	char *textbuf, size_t textlen )
{
	Modifications *ocmod = NULL;

	for( ; mods != NULL; mods = mods->sml_next ) {
		if( mods->sml_desc == slap_schema.si_ad_objectClass ) {
			if( ocmod != NULL ) {
				*text = "entry has multiple objectClass attributes";
				return LDAP_OBJECT_CLASS_VIOLATION;
			}
			ocmod = mods;
		}
	}

	if( ocmod == NULL ) {
		*text = "entry has no objectClass attribute";
		return LDAP_OBJECT_CLASS_VIOLATION;
	}

	if( ocmod->sml_bvalues == NULL || ocmod->sml_bvalues[0] == NULL ) {
		*text = "objectClass attribute has no values";
		return LDAP_OBJECT_CLASS_VIOLATION;
	}

	return structural_class( ocmod->sml_bvalues, sc,
		text, textbuf, textlen );
}

/*
 * entry_schema_check - check that entry e conforms to the schema required
 * by its object class(es).
 *
 * returns 0 if so, non-zero otherwise.
 */

int
entry_schema_check( 
	Entry *e, Attribute *oldattrs,
	const char** text,
	char *textbuf, size_t textlen )
{
	Attribute	*a, *asc, *aoc;
	ObjectClass *sc, *oc;
	int	rc, i;
	struct berval nsc;
	AttributeDescription *ad_structuralObjectClass
		= slap_schema.si_ad_structuralObjectClass;
	AttributeDescription *ad_objectClass
		= slap_schema.si_ad_objectClass;
	int extensible = 0;

	*text = textbuf;

	/* check single-valued attrs for multiple values */
	for ( a = e->e_attrs; a != NULL; a = a->a_next ) {
		/* there should be at least one value */
		assert( a->a_vals );
		assert( a->a_vals[0] != NULL ); 

		/* if single value type, check for multiple values */
		if( is_at_single_value( a->a_desc->ad_type ) &&
			a->a_vals[1] != NULL )
		{
			char *type = a->a_desc->ad_cname.bv_val;

			snprintf( textbuf, textlen, 
				"attribute '%s' cannot have multiple values",
				type );

#ifdef NEW_LOGGING
			LDAP_LOG(( "schema", LDAP_LEVEL_INFO,
				"entry_schema_check: dn=\"%s\" %s\n",
				e->e_dn, textbuf ));
#else
			Debug( LDAP_DEBUG_ANY,
			    "Entry (%s), %s\n",
			    e->e_dn, textbuf, 0 );
#endif

			return LDAP_CONSTRAINT_VIOLATION;
		}
	}

	if( !global_schemacheck ) return LDAP_SUCCESS;

	/* find the object class attribute - could error out here */
	asc = attr_find( e->e_attrs, ad_structuralObjectClass );
	if ( asc == NULL ) {
#ifdef NEW_LOGGING
		LDAP_LOG(( "schema", LDAP_LEVEL_INFO, "entry_schema_check: "
			"No structuralObjectClass for entry (%s)\n",
			e->e_dn ));
#else
		Debug( LDAP_DEBUG_ANY,
			"No structuralObjectClass for entry (%s)\n",
		    e->e_dn, 0, 0 );
#endif

		*text = "no structuralObjectClass operational attribute";
		return LDAP_OBJECT_CLASS_VIOLATION;
	}

	assert( asc->a_vals != NULL );
	assert( asc->a_vals[0] != NULL );
	assert( asc->a_vals[1] == NULL );

	sc = oc_find( asc->a_vals[0]->bv_val );
	if( sc == NULL ) {
		snprintf( textbuf, textlen, 
			"unrecognized structuralObjectClass '%s'",
			aoc->a_vals[0]->bv_val );

#ifdef NEW_LOGGING
		LDAP_LOG(( "schema", LDAP_LEVEL_INFO,
			"entry_schema_check: dn (%s), %s\n",
			e->e_dn, textbuf ));
#else
		Debug( LDAP_DEBUG_ANY,
			"entry_check_schema(%s): %s\n",
			e->e_dn, textbuf, 0 );
#endif

		return LDAP_OBJECT_CLASS_VIOLATION;
	}

	if( sc->soc_kind != LDAP_SCHEMA_STRUCTURAL ) {
		snprintf( textbuf, textlen, 
			"structuralObjectClass '%s' is not STRUCTURAL",
			aoc->a_vals[0]->bv_val );

#ifdef NEW_LOGGING
		LDAP_LOG(( "schema", LDAP_LEVEL_INFO,
			"entry_schema_check: dn (%s), %s\n",
			e->e_dn, textbuf ));
#else
		Debug( LDAP_DEBUG_ANY,
			"entry_check_schema(%s): %s\n",
			e->e_dn, textbuf, 0 );
#endif

		return LDAP_OBJECT_CLASS_VIOLATION;
	}

	/* find the object class attribute */
	aoc = attr_find( e->e_attrs, ad_objectClass );
	if ( aoc == NULL ) {
#ifdef NEW_LOGGING
		LDAP_LOG(( "schema", LDAP_LEVEL_INFO,
			"entry_schema_check: No objectClass for entry (%s).\n", e->e_dn ));
#else
		Debug( LDAP_DEBUG_ANY, "No objectClass for entry (%s)\n",
		    e->e_dn, 0, 0 );
#endif

		*text = "no objectClass attribute";
		return LDAP_OBJECT_CLASS_VIOLATION;
	}

	assert( aoc->a_vals != NULL );
	assert( aoc->a_vals[0] != NULL );

	rc = structural_class( aoc->a_vals, &nsc, text, textbuf, textlen );
	if( rc != LDAP_SUCCESS ) {
		return rc;
	} else if ( nsc.bv_len == 0 ) {
		return LDAP_OBJECT_CLASS_VIOLATION;
	}

	*text = textbuf;

	oc = oc_find( nsc.bv_val );
	if ( oc == NULL ) {
		snprintf( textbuf, textlen, 
			"unrecognized objectClass '%s'",
			aoc->a_vals[i]->bv_val );
		return LDAP_OBJECT_CLASS_VIOLATION;

	} else if ( sc != oc ) {
		snprintf( textbuf, textlen, 
			"structuralObjectClass modification from '%s' to '%s' not allowed",
			asc->a_vals[0]->bv_val, nsc.bv_val );
		return LDAP_NO_OBJECT_CLASS_MODS;
	}

	/* check that the entry has required attrs for each oc */
	for ( i = 0; aoc->a_vals[i] != NULL; i++ ) {
		if ( (oc = oc_find( aoc->a_vals[i]->bv_val )) == NULL ) {
			snprintf( textbuf, textlen, 
				"unrecognized objectClass '%s'",
				aoc->a_vals[i]->bv_val );

#ifdef NEW_LOGGING
			LDAP_LOG(( "schema", LDAP_LEVEL_INFO,
				"entry_schema_check: dn (%s), %s\n",
				e->e_dn, textbuf ));
#else
			Debug( LDAP_DEBUG_ANY,
				"entry_check_schema(%s): \"%s\" not recognized\n",
				e->e_dn, textbuf, 0 );
#endif

			return LDAP_OBJECT_CLASS_VIOLATION;

		} else if ( oc->soc_kind == LDAP_SCHEMA_ABSTRACT ) {
			/* object class is abstract */
			/* FIXME: need to check that is is a superclass of something */

		} else if ( oc->soc_kind == LDAP_SCHEMA_STRUCTURAL && oc != sc ) {
			/* object class is a superclass of the structural class */
			/* nothing in particular to check */

		} else {
			char *s = oc_check_required( e, oc, aoc->a_vals[i] );

			if (s != NULL) {
				snprintf( textbuf, textlen, 
					"object class '%s' requires attribute '%s'",
					aoc->a_vals[i]->bv_val, s );

#ifdef NEW_LOGGING
				LDAP_LOG(( "schema", LDAP_LEVEL_INFO,
					"entry_schema_check: dn=\"%s\" %s",
					e->e_dn, textbuf ));
#else
				Debug( LDAP_DEBUG_ANY,
					"Entry (%s): %s\n",
					e->e_dn, textbuf, 0 );
#endif

				return LDAP_OBJECT_CLASS_VIOLATION;
			}

			if( oc == slap_schema.si_oc_extensibleObject ) {
				extensible=1;
			}
		}
	}

	if( extensible ) {
		return LDAP_SUCCESS;
	}

	/* check that each attr in the entry is allowed by some oc */
	for ( a = e->e_attrs; a != NULL; a = a->a_next ) {
		int ret = oc_check_allowed( a->a_desc->ad_type, aoc->a_vals );
		if ( ret != LDAP_SUCCESS ) {
			char *type = a->a_desc->ad_cname.bv_val;

			snprintf( textbuf, textlen, 
				"attribute '%s' not allowed",
				type );

#ifdef NEW_LOGGING
			LDAP_LOG(( "schema", LDAP_LEVEL_INFO,
				"entry_schema_check: dn=\"%s\" %s\n",
				e->e_dn, textbuf ));
#else
			Debug( LDAP_DEBUG_ANY,
			    "Entry (%s), %s\n",
			    e->e_dn, textbuf, 0 );
#endif

			return ret;
		}
	}

	return LDAP_SUCCESS;
}

static char *
oc_check_required(
	Entry *e,
	ObjectClass *oc,
	struct berval *ocname )
{
	AttributeType	*at;
	int		i;
	Attribute	*a;

#ifdef NEW_LOGGING
	LDAP_LOG(( "schema", LDAP_LEVEL_ENTRY,
		"oc_check_required: dn (%s), objectClass \"%s\"\n",
	e->e_dn, ocname->bv_val ));
#else
	Debug( LDAP_DEBUG_TRACE,
		"oc_check_required entry (%s), objectClass \"%s\"\n",
		e->e_dn, ocname->bv_val, 0 );
#endif


	/* check for empty oc_required */
	if(oc->soc_required == NULL) {
		return NULL;
	}

	/* for each required attribute */
	for ( i = 0; oc->soc_required[i] != NULL; i++ ) {
		at = oc->soc_required[i];
		/* see if it's in the entry */
		for ( a = e->e_attrs; a != NULL; a = a->a_next ) {
			if( a->a_desc->ad_type == at ) {
				break;
			}
		}
		/* not there => schema violation */
		if ( a == NULL ) {
			return at->sat_cname.bv_val;
		}
	}

	return( NULL );
}

int oc_check_allowed(
	AttributeType *at,
	struct berval **ocl )
{
	ObjectClass	*oc;
	int		i, j;

#ifdef NEW_LOGGING
	LDAP_LOG(( "schema", LDAP_LEVEL_ENTRY,
		"oc_check_allowed: type \"%s\"\n", at->sat_cname.bv_val ));
#else
	Debug( LDAP_DEBUG_TRACE,
		"oc_check_allowed type \"%s\"\n",
		at->sat_cname.bv_val, 0, 0 );
#endif

	/* always allow objectClass attribute */
	if ( strcasecmp( at->sat_cname.bv_val, "objectClass" ) == 0 ) {
		return LDAP_SUCCESS;
	}

	/*
	 * All operational attributions are allowed by schema rules.
	 */
	if( is_at_operational(at) ) {
		return LDAP_SUCCESS;
	}

	/* check that the type appears as req or opt in at least one oc */
	for ( i = 0; ocl[i] != NULL; i++ ) {
		/* if we know about the oc */
		if ( (oc = oc_find( ocl[i]->bv_val )) != NULL ) {
			/* does it require the type? */
			for ( j = 0; oc->soc_required != NULL && 
				oc->soc_required[j] != NULL; j++ )
			{
				if( at == oc->soc_required[j] ) {
					return LDAP_SUCCESS;
				}
			}
			/* does it allow the type? */
			for ( j = 0; oc->soc_allowed != NULL && 
				oc->soc_allowed[j] != NULL; j++ )
			{
				if( at == oc->soc_allowed[j] ) {
					return LDAP_SUCCESS;
				}
			}
			/* maybe the next oc allows it */
		}
	}

	/* not allowed by any oc */
	return LDAP_OBJECT_CLASS_VIOLATION;
}