389-ds-base/ldap/servers/plugins/bitwise/bitwise.c

/** BEGIN COPYRIGHT BLOCK
 * This Program is free software; you can redistribute it and/or modify it under
 * the terms of the GNU General Public License as published by the Free Software
 * Foundation; version 2 of the License.
 * 
 * This Program is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
 * FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License along with
 * this Program; if not, write to the Free Software Foundation, Inc., 59 Temple
 * Place, Suite 330, Boston, MA 02111-1307 USA.
 * 
 * In addition, as a special exception, Red Hat, Inc. gives You the additional
 * right to link the code of this Program with code not covered under the GNU
 * General Public License ("Non-GPL Code") and to distribute linked combinations
 * including the two, subject to the limitations in this paragraph. Non-GPL Code
 * permitted under this exception must only link to the code of this Program
 * through those well defined interfaces identified in the file named EXCEPTION
 * found in the source code files (the "Approved Interfaces"). The files of
 * Non-GPL Code may instantiate templates or use macros or inline functions from
 * the Approved Interfaces without causing the resulting work to be covered by
 * the GNU General Public License. Only Red Hat, Inc. may make changes or
 * additions to the list of Approved Interfaces. You must obey the GNU General
 * Public License in all respects for all of the Program code and other code used
 * in conjunction with the Program except the Non-GPL Code covered by this
 * exception. If you modify this file, you may extend this exception to your
 * version of the file, but you are not obligated to do so. If you do not wish to
 * provide this exception without modification, you must delete this exception
 * statement from your version and license this file solely under the GPL without
 * exception. 
 * 
 * 
 * Copyright (C) 2007 Red Hat, Inc.
 * All rights reserved.
 * END COPYRIGHT BLOCK **/

#ifdef HAVE_CONFIG_H
#  include <config.h>
#endif

/* orfilter.c - implementation of ordering rule filter */

#include <ldap.h> /* LDAP_UTF8INC */
#include <slap.h> /* for debug macros */
#include <slapi-plugin.h> /* slapi_berval_cmp, SLAPI_BERVAL_EQ */

#ifdef HPUX11
#include <dl.h>
#endif /* HPUX11 */

/* the match function needs the attribute type and value from the search
   filter - this is unfortunately not passed into the match fn, so we
   have to keep track of this
*/
struct bitwise_match_cb {
    char *type; /* the attribute type from the filter ava */
    struct berval *val; /* the value from the filter ava */
};

/*
  The type and val pointers are assumed to have sufficient lifetime -
  we don't have to copy them - they are usually just pointers into
  the SLAPI_PLUGIN_MR_TYPE and SLAPI_PLUGIN_MR_VALUE fields of the
  operation pblock, whose lifetime should encompass the creation
  and destruction of the bitwise_match_cb object.
*/
static struct bitwise_match_cb *
new_bitwise_match_cb(char *type, struct berval *val)
{
    struct bitwise_match_cb *bmc = (struct bitwise_match_cb *)slapi_ch_calloc(1, sizeof(struct bitwise_match_cb));
    bmc->type = slapi_ch_strdup(type);
    bmc->val = val;

    return bmc;
}

static void
delete_bitwise_match_cb(struct bitwise_match_cb *bmc)
{
    slapi_ch_free_string(&bmc->type);
    slapi_ch_free((void **)&bmc);
}

static void
bitwise_filter_destroy(Slapi_PBlock* pb)
{
    void *obj = NULL;
    slapi_pblock_get(pb, SLAPI_PLUGIN_OBJECT, &obj);
    if (obj) {
	struct bitwise_match_cb *bmc = (struct bitwise_match_cb *)obj;
	delete_bitwise_match_cb(bmc);
	obj = NULL;
	slapi_pblock_set(pb, SLAPI_PLUGIN_OBJECT, obj);
    }
}

#define BITWISE_OP_AND  0
#define BITWISE_OP_OR   1

static int
internal_bitwise_filter_match(void* obj, Slapi_Entry* entry, Slapi_Attr* attr, int op)
/* returns:  0  filter matched
 *	    -1  filter did not match
 *	    >0  an LDAP error code
 */
{
    struct bitwise_match_cb *bmc = obj;
    auto int rc = -1; /* no match */
    char **ary = NULL;
    int ii;

    ary = slapi_entry_attr_get_charray(entry, bmc->type);

    /* look through all values until we find a match */
    for (ii = 0; (rc == -1) && ary && ary[ii]; ++ii) {
	unsigned long long a, b;
	char *val_from_entry = ary[ii];
	errno = 0;
	a = strtoull(val_from_entry, NULL, 10);
	if (errno != ERANGE) {
	    errno = 0;
	    b = strtoull(bmc->val->bv_val, NULL, 10);
	    if (errno == ERANGE) {
		rc = LDAP_CONSTRAINT_VIOLATION;
	    } else {
		int result = 0;
		/* The Microsoft Windows AD bitwise operators do not work exactly
		   as the plain old C bitwise operators work.  For the AND case
		   the matching rule is true only if all bits from the given value
		   match the value from the entry.  For the OR case, the matching
		   rule is true if any bits from the given value match the value
		   from the entry.
		   For the AND case, this means that even though (a & b) is True,
		   if (a & b) != b, the matching rule will return False.
		   For the OR case, this means that even though (a | b) is True,
		   this may be because there are bits in a.  But we only care
		   about bits in a that are also in b.  So we do (a & b) - this
		   will return what we want, which is to return True if any of
		   the bits in b are also in a.
		*/
		if (op == BITWISE_OP_AND) {
		    result = ((a & b) == b); /* all the bits in the given value are found in the value from the entry */
		} else if (op == BITWISE_OP_OR) {
		    result = (a & b); /* any of the bits in b are also in a */
		}
		if (result) {
		    rc = 0;
		}
	    }
	}
    }
    slapi_ch_array_free(ary);
    return rc;
}

static int
bitwise_filter_match_and (void* obj, Slapi_Entry* entry, Slapi_Attr* attr)
/* returns:  0  filter matched
 *	    -1  filter did not match
 *	    >0  an LDAP error code
 */
{
    return internal_bitwise_filter_match(obj, entry, attr, BITWISE_OP_AND);
}

static int
bitwise_filter_match_or (void* obj, Slapi_Entry* entry, Slapi_Attr* attr)
/* returns:  0  filter matched
 *	    -1  filter did not match
 *	    >0  an LDAP error code
 */
{
    return internal_bitwise_filter_match(obj, entry, attr, BITWISE_OP_OR);
}

static int
bitwise_filter_create (Slapi_PBlock* pb)
{
    auto int rc = LDAP_UNAVAILABLE_CRITICAL_EXTENSION; /* failed to initialize */
    auto char* mrOID = NULL;
    auto char* mrTYPE = NULL;
    auto struct berval* mrVALUE = NULL;

    if (!slapi_pblock_get (pb, SLAPI_PLUGIN_MR_OID, &mrOID) && mrOID != NULL &&
	!slapi_pblock_get (pb, SLAPI_PLUGIN_MR_TYPE, &mrTYPE) && mrTYPE != NULL &&
	!slapi_pblock_get (pb, SLAPI_PLUGIN_MR_VALUE, &mrVALUE) && mrVALUE != NULL) {

	struct bitwise_match_cb *bmc = NULL;
	if (strcmp(mrOID, "1.2.840.113556.1.4.803") == 0) {
	    slapi_pblock_set (pb, SLAPI_PLUGIN_MR_FILTER_MATCH_FN, (void*)bitwise_filter_match_and);
	} else if (strcmp(mrOID, "1.2.840.113556.1.4.804") == 0) {
	    slapi_pblock_set (pb, SLAPI_PLUGIN_MR_FILTER_MATCH_FN, (void*)bitwise_filter_match_or);
	} else { /* this oid not handled by this plugin */
	    LDAPDebug (LDAP_DEBUG_FILTER, "=> bitwise_filter_create OID (%s) not handled\n", mrOID, 0, 0);
	    return rc;
	}
	bmc = new_bitwise_match_cb(mrTYPE, mrVALUE);
	slapi_pblock_set (pb, SLAPI_PLUGIN_OBJECT, bmc);
	slapi_pblock_set (pb, SLAPI_PLUGIN_DESTROY_FN, (void*)bitwise_filter_destroy);
	rc = LDAP_SUCCESS;
    } else {
	LDAPDebug (LDAP_DEBUG_FILTER, "=> bitwise_filter_create missing parameter(s)\n", 0, 0, 0);
    }
    LDAPDebug (LDAP_DEBUG_FILTER, "<= bitwise_filter_create %i\n", rc, 0, 0);
    return LDAP_SUCCESS;
}

static Slapi_PluginDesc pdesc = { "bitwise", VENDOR, DS_PACKAGE_VERSION,
              "bitwise match plugin" };

int /* LDAP error code */
bitwise_init (Slapi_PBlock* pb)
{
    int rc;

    rc = slapi_pblock_set (pb, SLAPI_PLUGIN_MR_FILTER_CREATE_FN, (void*)bitwise_filter_create);
    if ( rc == 0 ) {
	rc = slapi_pblock_set( pb, SLAPI_PLUGIN_DESCRIPTION, (void *)&pdesc );
    }
    LDAPDebug (LDAP_DEBUG_FILTER, "bitwise_init %i\n", rc, 0, 0);
    return rc;
}