acl.h revision ec5347e2c775f027573ce5648b910361aa926c01
/*
* Copyright (C) 2004-2006 Internet Systems Consortium, Inc. ("ISC")
* Copyright (C) 1999-2002 Internet Software Consortium.
*
* Permission to use, copy, modify, and/or distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
* REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
* AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
* INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
* LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
* OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
* PERFORMANCE OF THIS SOFTWARE.
*/
/* $Id: acl.h,v 1.28 2007/06/18 23:47:42 tbox Exp $ */
#ifndef DNS_ACL_H
#define DNS_ACL_H 1
/*****
***** Module Info
*****/
/*! \file dns/acl.h
* \brief
* Address match list handling.
*/
/***
*** Imports
***/
#include <isc/lang.h>
#include <isc/magic.h>
#include <isc/netaddr.h>
#include <isc/refcount.h>
#include <dns/name.h>
#include <dns/types.h>
/***
*** Types
***/
typedef enum {
dns_aclelementtype_ipprefix,
dns_aclelementtype_keyname,
dns_aclelementtype_nestedacl,
dns_aclelementtype_localhost,
dns_aclelementtype_localnets,
dns_aclelementtype_any
} dns_aclelemettype_t;
typedef struct dns_aclipprefix dns_aclipprefix_t;
struct dns_aclipprefix {
isc_netaddr_t address; /* IP4/IP6 */
unsigned int prefixlen;
};
struct dns_aclelement {
dns_aclelemettype_t type;
isc_boolean_t negative;
union {
dns_aclipprefix_t ip_prefix;
dns_name_t keyname;
dns_acl_t *nestedacl;
} u;
};
struct dns_acl {
unsigned int magic;
isc_mem_t *mctx;
isc_refcount_t refcount;
dns_aclelement_t *elements;
unsigned int alloc; /*%< Elements allocated */
unsigned int length; /*%< Elements initialized */
char *name; /*%< Temporary use only */
ISC_LINK(dns_acl_t) nextincache; /*%< Ditto */
};
struct dns_aclenv {
dns_acl_t *localhost;
dns_acl_t *localnets;
isc_boolean_t match_mapped;
};
#define DNS_ACL_MAGIC ISC_MAGIC('D','a','c','l')
#define DNS_ACL_VALID(a) ISC_MAGIC_VALID(a, DNS_ACL_MAGIC)
/***
*** Functions
***/
ISC_LANG_BEGINDECLS
isc_result_t
dns_acl_create(isc_mem_t *mctx, int n, dns_acl_t **target);
/*%<
* Create a new ACL with room for 'n' elements.
* The elements are uninitialized and the length is 0.
*/
isc_result_t
dns_acl_appendelement(dns_acl_t *acl, const dns_aclelement_t *elt);
/*%<
* Append an element to an existing ACL.
*/
isc_result_t
dns_acl_any(isc_mem_t *mctx, dns_acl_t **target);
/*%<
* Create a new ACL that matches everything.
*/
isc_result_t
dns_acl_none(isc_mem_t *mctx, dns_acl_t **target);
/*%<
* Create a new ACL that matches nothing.
*/
void
dns_acl_attach(dns_acl_t *source, dns_acl_t **target);
void
dns_acl_detach(dns_acl_t **aclp);
isc_boolean_t
dns_aclelement_equal(const dns_aclelement_t *ea, const dns_aclelement_t *eb);
isc_boolean_t
dns_acl_equal(const dns_acl_t *a, const dns_acl_t *b);
isc_boolean_t
dns_acl_isinsecure(const dns_acl_t *a);
/*%<
* Return #ISC_TRUE iff the acl 'a' is considered insecure, that is,
* if it contains IP addresses other than those of the local host.
* This is intended for applications such as printing warning
* messages for suspect ACLs; it is not intended for making access
* control decisions. We make no guarantee that an ACL for which
* this function returns #ISC_FALSE is safe.
*/
isc_result_t
dns_aclenv_init(isc_mem_t *mctx, dns_aclenv_t *env);
void
dns_aclenv_copy(dns_aclenv_t *t, dns_aclenv_t *s);
void
dns_aclenv_destroy(dns_aclenv_t *env);
isc_result_t
dns_acl_match(const isc_netaddr_t *reqaddr,
const dns_name_t *reqsigner,
const dns_acl_t *acl,
const dns_aclenv_t *env,
int *match,
const dns_aclelement_t **matchelt);
/*%<
* General, low-level ACL matching. This is expected to
* be useful even for weird stuff like the topology and sortlist statements.
*
* Match the address 'reqaddr', and optionally the key name 'reqsigner',
* against 'acl'. 'reqsigner' may be NULL.
*
* If there is a positive match, '*match' will be set to a positive value
* indicating the distance from the beginning of the list.
*
* If there is a negative match, '*match' will be set to a negative value
* whose absolute value indicates the distance from the beginning of
* the list.
*
* If there is a match (either positive or negative) and 'matchelt' is
* non-NULL, *matchelt will be attached to the primitive
* (non-indirect) address match list element that matched.
*
* If there is no match, *match will be set to zero.
*
* Returns:
*\li #ISC_R_SUCCESS Always succeeds.
*/
isc_boolean_t
dns_aclelement_match(const isc_netaddr_t *reqaddr,
const dns_name_t *reqsigner,
const dns_aclelement_t *e,
const dns_aclenv_t *env,
const dns_aclelement_t **matchelt);
/*%<
* Like dns_acl_match, but matches against the single ACL element 'e'
* rather than a complete list and returns ISC_TRUE iff it matched.
* To determine whether the match was prositive or negative, the
* caller should examine e->negative. Since the element 'e' may be
* a reference to a named ACL or a nested ACL, the matching element
* returned through 'matchelt' is not necessarily 'e' itself.
*/
isc_result_t
dns_acl_elementmatch(const dns_acl_t *acl,
const dns_aclelement_t *elt,
const dns_aclelement_t **matchelt);
/*%<
* Search for an ACL element in 'acl' which is exactly the same as 'elt'.
* If there is one, and 'matchelt' is non NULL, then '*matchelt' will point
* to the entry.
*
* This function is intended to be used for avoiding duplicated ACL entries
* before adding an entry.
*
* Returns:
*\li #ISC_R_SUCCESS Match succeeds.
*\li #ISC_R_NOTFOUND Match fails.
*/
ISC_LANG_ENDDECLS
#endif /* DNS_ACL_H */