/* * Copyright (C) Internet Systems Consortium, Inc. ("ISC") * * This Source Code Form is subject to the terms of the Mozilla Public * License, v. 2.0. If a copy of the MPL was not distributed with this * file, you can obtain one at https://mozilla.org/MPL/2.0/. * * See the COPYRIGHT file distributed with this work for additional * information regarding copyright ownership. */ #ifndef DNS_ACL_H #define DNS_ACL_H 1 /***** ***** Module Info *****/ /*! \file dns/acl.h * \brief * Address match list handling. */ /*** *** Imports ***/ #include <stdbool.h> #include <isc/lang.h> #include <isc/magic.h> #include <isc/netaddr.h> #include <isc/refcount.h> #include <dns/geoip.h> #include <dns/iptable.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, #if defined(HAVE_GEOIP2) dns_aclelementtype_geoip, #endif /* HAVE_GEOIP2 */ dns_aclelementtype_any } dns_aclelementtype_t; typedef struct dns_aclipprefix dns_aclipprefix_t; struct dns_aclipprefix { isc_netaddr_t address; /* IP4/IP6 */ unsigned int prefixlen; }; struct dns_aclelement { dns_aclelementtype_t type; bool negative; dns_name_t keyname; #if defined(HAVE_GEOIP2) dns_geoip_elem_t geoip_elem; #endif /* HAVE_GEOIP2 */ dns_acl_t *nestedacl; int node_num; }; #define dns_acl_node_count(acl) acl->iptable->radix->num_added_node struct dns_acl { unsigned int magic; isc_mem_t *mctx; isc_refcount_t refcount; dns_iptable_t *iptable; dns_aclelement_t *elements; bool has_negatives; 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; bool match_mapped; #if defined(HAVE_GEOIP2) dns_geoip_databases_t *geoip; #endif /* HAVE_GEOIP2 */ }; #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, including an IP table and an array with room * for 'n' ACL elements. The elements are uninitialized and the * length is 0. */ 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. */ bool dns_acl_isany(dns_acl_t *acl); /*%< * Test whether ACL is set to "{ any; }" */ bool dns_acl_isnone(dns_acl_t *acl); /*%< * Test whether ACL is set to "{ none; }" */ isc_result_t dns_acl_merge(dns_acl_t *dest, dns_acl_t *source, bool pos); /*%< * Merge the contents of one ACL into another. Call dns_iptable_merge() * for the IP tables, then concatenate the element arrays. * * If pos is set to false, then the nested ACL is to be negated. This * means reverse the sense of each *positive* element or IP table node, * but leave negatives alone, so as to prevent a double-negative causing * an unexpected positive match in the parent ACL. */ void dns_acl_attach(dns_acl_t *source, dns_acl_t **target); /*%< * Attach to acl 'source'. * * Requires: *\li 'source' to be a valid acl. *\li 'target' to be non NULL and '*target' to be NULL. */ void dns_acl_detach(dns_acl_t **aclp); /*%< * Detach the acl. On final detach the acl must not be linked on any * list. * * Requires: *\li '*aclp' to be a valid acl. * * Insists: *\li '*aclp' is not linked on final detach. */ bool dns_acl_isinsecure(const dns_acl_t *a); /*%< * Return #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 #false is safe. */ bool dns_acl_allowed(isc_netaddr_t *addr, const dns_name_t *signer, dns_acl_t *acl, dns_aclenv_t *aclenv); /*%< * Return #true iff the 'addr', 'signer', or ECS values are * permitted by 'acl' in environment 'aclenv'. */ isc_result_t dns_aclenv_init(isc_mem_t *mctx, dns_aclenv_t *env); /*%< * Initialize ACL environment, setting up localhost and localnets ACLs */ 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 match, '*match' will be set to an integer whose absolute * value corresponds to the order in which the matching value was inserted * into the ACL. For a positive match, this value will be positive; for a * negative match, it will be negative. * * If there is no match, *match will be set to zero. * * If there is a match in the element list (either positive or negative) * and 'matchelt' is non-NULL, *matchelt will be pointed to the matching * element. * * 'env' points to the current ACL environment, including the * current values of localhost and localnets and (if applicable) * the GeoIP context. * * Returns: *\li #ISC_R_SUCCESS Always succeeds. */ bool 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 ACL, and returns true iff it matched. * * To determine whether the match was positive or negative, the * caller should examine e->negative. Since the element 'e' may be * a reference to a named ACL or a nested ACL, a matching element * returned through 'matchelt' is not necessarily 'e' itself. */ ISC_LANG_ENDDECLS #endif /* DNS_ACL_H */