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Diffstat (limited to 'lib/dns/include/dns/acl.h')
| -rw-r--r-- | lib/dns/include/dns/acl.h | 337 |
1 files changed, 337 insertions, 0 deletions
diff --git a/lib/dns/include/dns/acl.h b/lib/dns/include/dns/acl.h new file mode 100644 index 0000000..a2f303b --- /dev/null +++ b/lib/dns/include/dns/acl.h @@ -0,0 +1,337 @@ +/* + * Copyright (C) Internet Systems Consortium, Inc. ("ISC") + * + * SPDX-License-Identifier: MPL-2.0 + * + * 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. + */ + +#pragma once + +/***** +***** 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 <isc/rwlock.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_acl_port_transports { + in_port_t port; + uint32_t transports; + bool encrypted; /* for protocols with optional encryption (e.g. HTTP) */ + bool negative; + ISC_LINK(struct dns_acl_port_transports) link; +} dns_acl_port_transports_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 */ + ISC_LIST(dns_acl_port_transports_t) ports_and_transports; + size_t port_proto_entries; +}; + +struct dns_aclenv { + unsigned int magic; + isc_mem_t *mctx; + isc_refcount_t references; + + isc_rwlock_t rwlock; /*%< Locks localhost and localnets */ + 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_create(isc_mem_t *mctx, dns_aclenv_t **envp); +/*%< + * Create ACL environment, setting up localhost and localnets ACLs + */ + +void +dns_aclenv_copy(dns_aclenv_t *t, dns_aclenv_t *s); +/*%< + * Copy the ACLs from one ACL environment object to another. + * + * Requires: + *\li both 's' and 't' are valid ACL environments. + */ + +void +dns_aclenv_set(dns_aclenv_t *env, dns_acl_t *localhost, dns_acl_t *localnets); +/*%< + * Attach the 'localhost' and 'localnets' arguments to 'env' ACL environment + */ + +void +dns_aclenv_attach(dns_aclenv_t *source, dns_aclenv_t **targetp); +/*%< + * Attach '*targetp' to ACL environment 'source'. + * + * Requires: + *\li 'source' is a valid ACL environment. + *\li 'targetp' is not NULL and '*targetp' is NULL. + */ + +void +dns_aclenv_detach(dns_aclenv_t **aclenvp); +/*%< + * Detach an ACL environment; on final detach, destroy it. + * + * Requires: + *\li '*aclenvp' to be a valid ACL environment + */ + +isc_result_t +dns_acl_match(const isc_netaddr_t *reqaddr, const dns_name_t *reqsigner, + const dns_acl_t *acl, 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, 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_result_t +dns_acl_match_port_transport(const isc_netaddr_t *reqaddr, + const in_port_t local_port, + const isc_nmsocket_type_t transport, + const bool encrypted, const dns_name_t *reqsigner, + const dns_acl_t *acl, dns_aclenv_t *env, + int *match, const dns_aclelement_t **matchelt); +/*%< + * Like dns_acl_match, but able to match the server port and + * transport, as well as encryption status. + * + * Requires: + *\li 'reqaddr' is not 'NULL'; + *\li 'acl' is a valid ACL object. + */ + +void +dns_acl_add_port_transports(dns_acl_t *acl, const in_port_t port, + const uint32_t transports, const bool encrypted, + const bool negative); +/*%< + * Adds a "port-transports" entry to the specified ACL. Transports + * are specified as a bit-set 'transports' consisting of entries + * defined in the isc_nmsocket_type enumeration. + * + * Requires: + *\li 'acl' is a valid ACL object; + *\li either 'port' or 'transports' is not equal to 0. + */ + +void +dns_acl_merge_ports_transports(dns_acl_t *dest, dns_acl_t *source, bool pos); +/*%< + * Merges "port-transports" entries from the 'dest' ACL into + * the 'source' ACL. The 'pos' parameter works in a way similar to + * 'dns_acl_merge()'. + * + * Requires: + *\li 'dest' is a valid ACL object; + *\li 'source' is a valid ACL object. + */ + +ISC_LANG_ENDDECLS |