| Current File : //usr/include/bind9/dns/rpz.h |
/*
* 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_RPZ_H
#define DNS_RPZ_H 1
#include <stdbool.h>
#include <isc/deprecated.h>
#include <isc/event.h>
#include <isc/ht.h>
#include <isc/lang.h>
#include <isc/refcount.h>
#include <isc/rwlock.h>
#include <dns/fixedname.h>
#include <dns/rdata.h>
#include <dns/types.h>
ISC_LANG_BEGINDECLS
#define DNS_RPZ_PREFIX "rpz-"
/*
* Sub-zones of various trigger types.
*/
#define DNS_RPZ_CLIENT_IP_ZONE DNS_RPZ_PREFIX"client-ip"
#define DNS_RPZ_IP_ZONE DNS_RPZ_PREFIX"ip"
#define DNS_RPZ_NSIP_ZONE DNS_RPZ_PREFIX"nsip"
#define DNS_RPZ_NSDNAME_ZONE DNS_RPZ_PREFIX"nsdname"
/*
* Special policies.
*/
#define DNS_RPZ_PASSTHRU_NAME DNS_RPZ_PREFIX"passthru"
#define DNS_RPZ_DROP_NAME DNS_RPZ_PREFIX"drop"
#define DNS_RPZ_TCP_ONLY_NAME DNS_RPZ_PREFIX"tcp-only"
typedef uint8_t dns_rpz_prefix_t;
typedef enum {
DNS_RPZ_TYPE_BAD,
DNS_RPZ_TYPE_CLIENT_IP,
DNS_RPZ_TYPE_QNAME,
DNS_RPZ_TYPE_IP,
DNS_RPZ_TYPE_NSDNAME,
DNS_RPZ_TYPE_NSIP
} dns_rpz_type_t;
/*
* Require DNS_RPZ_POLICY_PASSTHRU < DNS_RPZ_POLICY_DROP
* < DNS_RPZ_POLICY_TCP_ONLY DNS_RPZ_POLICY_NXDOMAIN < DNS_RPZ_POLICY_NODATA
* < DNS_RPZ_POLICY_CNAME to choose among competing policies.
*/
typedef enum {
DNS_RPZ_POLICY_GIVEN = 0, /* 'given': what policy record says */
DNS_RPZ_POLICY_DISABLED = 1, /* log what would have happened */
DNS_RPZ_POLICY_PASSTHRU = 2, /* 'passthru': do not rewrite */
DNS_RPZ_POLICY_DROP = 3, /* 'drop': do not respond */
DNS_RPZ_POLICY_TCP_ONLY = 4, /* 'tcp-only': answer UDP with TC=1 */
DNS_RPZ_POLICY_NXDOMAIN = 5, /* 'nxdomain': answer with NXDOMAIN */
DNS_RPZ_POLICY_NODATA = 6, /* 'nodata': answer with ANCOUNT=0 */
DNS_RPZ_POLICY_CNAME = 7, /* 'cname x': answer with x's rrsets */
DNS_RPZ_POLICY_DNS64, /* Apply DN64 to the A rewrite */
DNS_RPZ_POLICY_RECORD,
DNS_RPZ_POLICY_WILDCNAME,
DNS_RPZ_POLICY_MISS,
DNS_RPZ_POLICY_ERROR
} dns_rpz_policy_t;
typedef uint8_t dns_rpz_num_t;
#define DNS_RPZ_MAX_ZONES 32
#if DNS_RPZ_MAX_ZONES > 32
# if DNS_RPZ_MAX_ZONES > 64
# error "rpz zone bit masks must fit in a word"
# endif
typedef uint64_t dns_rpz_zbits_t;
#else
typedef uint32_t dns_rpz_zbits_t;
#endif
#define DNS_RPZ_ALL_ZBITS ((dns_rpz_zbits_t)-1)
#define DNS_RPZ_INVALID_NUM DNS_RPZ_MAX_ZONES
#define DNS_RPZ_ZBIT(n) (((dns_rpz_zbits_t)1) << (dns_rpz_num_t)(n))
/*
* Mask of the specified and higher numbered policy zones
* Avoid hassles with (1<<33) or (1<<65)
*/
#define DNS_RPZ_ZMASK(n) ((dns_rpz_zbits_t)((((n) >= DNS_RPZ_MAX_ZONES-1) ? \
0 : (1<<((n)+1))) -1))
/*
* The trigger counter type.
*/
typedef size_t dns_rpz_trigger_counter_t;
/*
* The number of triggers of each type in a response policy zone.
*/
typedef struct dns_rpz_triggers dns_rpz_triggers_t;
struct dns_rpz_triggers {
dns_rpz_trigger_counter_t client_ipv4;
dns_rpz_trigger_counter_t client_ipv6;
dns_rpz_trigger_counter_t qname;
dns_rpz_trigger_counter_t ipv4;
dns_rpz_trigger_counter_t ipv6;
dns_rpz_trigger_counter_t nsdname;
dns_rpz_trigger_counter_t nsipv4;
dns_rpz_trigger_counter_t nsipv6;
};
/*
* A single response policy zone.
*/
typedef struct dns_rpz_zone dns_rpz_zone_t;
struct dns_rpz_zone {
isc_refcount_t refs;
dns_rpz_num_t num; /* ordinal in list of policy zones */
dns_name_t origin; /* Policy zone name */
dns_name_t client_ip; /* DNS_RPZ_CLIENT_IP_ZONE.origin. */
dns_name_t ip; /* DNS_RPZ_IP_ZONE.origin. */
dns_name_t nsdname; /* DNS_RPZ_NSDNAME_ZONE.origin */
dns_name_t nsip; /* DNS_RPZ_NSIP_ZONE.origin. */
dns_name_t passthru; /* DNS_RPZ_PASSTHRU_NAME. */
dns_name_t drop; /* DNS_RPZ_DROP_NAME. */
dns_name_t tcp_only; /* DNS_RPZ_TCP_ONLY_NAME. */
dns_name_t cname; /* override value for ..._CNAME */
dns_ttl_t max_policy_ttl;
dns_rpz_policy_t policy; /* DNS_RPZ_POLICY_GIVEN or override */
};
/*
* Radix tree node for response policy IP addresses
*/
typedef struct dns_rpz_cidr_node dns_rpz_cidr_node_t;
/*
* Bitfields indicating which policy zones have policies of
* which type.
*/
typedef struct dns_rpz_have dns_rpz_have_t;
struct dns_rpz_have {
dns_rpz_zbits_t client_ipv4;
dns_rpz_zbits_t client_ipv6;
dns_rpz_zbits_t client_ip;
dns_rpz_zbits_t qname;
dns_rpz_zbits_t ipv4;
dns_rpz_zbits_t ipv6;
dns_rpz_zbits_t ip;
dns_rpz_zbits_t nsdname;
dns_rpz_zbits_t nsipv4;
dns_rpz_zbits_t nsipv6;
dns_rpz_zbits_t nsip;
dns_rpz_zbits_t qname_skip_recurse;
};
/*
* Policy options
*/
typedef struct dns_rpz_popt dns_rpz_popt_t;
struct dns_rpz_popt {
dns_rpz_zbits_t no_rd_ok;
dns_rpz_zbits_t no_log;
bool break_dnssec;
bool qname_wait_recurse;
bool nsip_wait_recurse;
unsigned int min_ns_labels;
dns_rpz_num_t num_zones;
};
/*
* Response policy zones known to a view.
*/
typedef struct dns_rpz_zones dns_rpz_zones_t;
struct dns_rpz_zones {
dns_rpz_popt_t p;
dns_rpz_zone_t *zones[DNS_RPZ_MAX_ZONES];
dns_rpz_triggers_t triggers[DNS_RPZ_MAX_ZONES];
/*
* RPZ policy version number (initially 0, increases whenever
* the server is reconfigured with new zones or policy)
*/
int rpz_ver;
dns_rpz_zbits_t defined;
/*
* The set of records for a policy zone are in one of these states:
* never loaded load_begun=0 have=0
* during initial loading load_begun=1 have=0
* and rbtdb->rpzsp == rbtdb->load_rpzsp
* after good load load_begun=1 have!=0
* after failed initial load load_begun=1 have=0
* and rbtdb->load_rpzsp == NULL
* reloading after failure load_begun=1 have=0
* reloading after success
* main rpzs load_begun=1 have!=0
* load rpzs load_begun=1 have=0
*/
dns_rpz_zbits_t load_begun;
dns_rpz_have_t have;
/*
* total_triggers maintains the total number of triggers in all
* policy zones in the view. It is only used to print summary
* statistics after a zone load of how the trigger counts
* changed.
*/
dns_rpz_triggers_t total_triggers;
isc_mem_t *mctx;
isc_refcount_t refs;
/*
* One lock for short term read-only search that guarantees the
* consistency of the pointers.
* A second lock for maintenance that guarantees no other thread
* is adding or deleting nodes.
*/
isc_rwlock_t search_lock;
isc_mutex_t maint_lock;
dns_rpz_cidr_node_t *cidr;
dns_rbt_t *rbt;
};
/*
* context for finding the best policy
*/
typedef struct {
unsigned int state;
# define DNS_RPZ_REWRITTEN 0x0001
# define DNS_RPZ_DONE_CLIENT_IP 0x0002 /* client IP address checked */
# define DNS_RPZ_DONE_QNAME 0x0004 /* qname checked */
# define DNS_RPZ_DONE_QNAME_IP 0x0008 /* IP addresses of qname checked */
# define DNS_RPZ_DONE_NSDNAME 0x0010 /* NS name missed; checking addresses */
# define DNS_RPZ_DONE_IPv4 0x0020
# define DNS_RPZ_RECURSING 0x0040
# define DNS_RPZ_ACTIVE 0x0080
/*
* Best match so far.
*/
struct {
dns_rpz_type_t type;
dns_rpz_zone_t *rpz;
dns_rpz_prefix_t prefix;
dns_rpz_policy_t policy;
dns_ttl_t ttl;
isc_result_t result;
dns_zone_t *zone;
dns_db_t *db;
dns_dbversion_t *version;
dns_dbnode_t *node;
dns_rdataset_t *rdataset;
} m;
/*
* State for chasing IP addresses and NS names including recursion.
*/
struct {
unsigned int label;
dns_db_t *db;
dns_rdataset_t *ns_rdataset;
dns_rdatatype_t r_type;
isc_result_t r_result;
dns_rdataset_t *r_rdataset;
} r;
/*
* State of real query while recursing for NSIP or NSDNAME.
*/
struct {
isc_result_t result;
bool is_zone;
bool authoritative;
dns_zone_t *zone;
dns_db_t *db;
dns_dbnode_t *node;
dns_rdataset_t *rdataset;
dns_rdataset_t *sigrdataset;
dns_rdatatype_t qtype;
} q;
/*
* A copy of the 'have' and 'p' structures and the RPZ
* policy version as of the beginning of RPZ processing,
* used to avoid problems when policy is updated while
* RPZ recursion is ongoing.
*/
dns_rpz_have_t have;
dns_rpz_popt_t popt;
int rpz_ver;
/*
* p_name: current policy owner name
* r_name: recursing for this name to possible policy triggers
* f_name: saved found name from before recursion
*/
dns_name_t *p_name;
dns_name_t *r_name;
dns_name_t *fname;
dns_fixedname_t _p_namef;
dns_fixedname_t _r_namef;
dns_fixedname_t _fnamef;
} dns_rpz_st_t;
#define DNS_RPZ_TTL_DEFAULT 5
#define DNS_RPZ_MAX_TTL_DEFAULT DNS_RPZ_TTL_DEFAULT
/*
* So various response policy zone messages can be turned up or down.
*/
#define DNS_RPZ_ERROR_LEVEL ISC_LOG_WARNING
#define DNS_RPZ_INFO_LEVEL ISC_LOG_INFO
#define DNS_RPZ_DEBUG_LEVEL1 ISC_LOG_DEBUG(1)
#define DNS_RPZ_DEBUG_LEVEL2 ISC_LOG_DEBUG(2)
#define DNS_RPZ_DEBUG_LEVEL3 ISC_LOG_DEBUG(3)
#define DNS_RPZ_DEBUG_QUIET (DNS_RPZ_DEBUG_LEVEL3+1)
const char *
dns_rpz_type2str(dns_rpz_type_t type);
dns_rpz_policy_t
dns_rpz_str2policy(const char *str);
const char *
dns_rpz_policy2str(dns_rpz_policy_t policy);
dns_rpz_policy_t
dns_rpz_decode_cname(dns_rpz_zone_t *rpz, dns_rdataset_t *rdataset,
dns_name_t *selfname);
isc_result_t
dns_rpz_new_zones(dns_rpz_zones_t **rpzsp, isc_mem_t *mctx);
void
dns_rpz_attach_rpzs(dns_rpz_zones_t *source, dns_rpz_zones_t **target);
void
dns_rpz_detach_rpzs(dns_rpz_zones_t **rpzsp);
isc_result_t
dns_rpz_beginload(dns_rpz_zones_t **load_rpzsp,
dns_rpz_zones_t *rpzs, dns_rpz_num_t rpz_num);
isc_result_t
dns_rpz_ready(dns_rpz_zones_t *rpzs,
dns_rpz_zones_t **load_rpzsp, dns_rpz_num_t rpz_num);
isc_result_t
dns_rpz_add(dns_rpz_zones_t *rpzs, dns_rpz_num_t rpz_num, dns_name_t *name);
void
dns_rpz_delete(dns_rpz_zones_t *rpzs, dns_rpz_num_t rpz_num, dns_name_t *name);
dns_rpz_num_t
dns_rpz_find_ip(dns_rpz_zones_t *rpzs, dns_rpz_type_t rpz_type,
dns_rpz_zbits_t zbits, const isc_netaddr_t *netaddr,
dns_name_t *ip_name, dns_rpz_prefix_t *prefixp);
dns_rpz_zbits_t
dns_rpz_find_name(dns_rpz_zones_t *rpzs, dns_rpz_type_t rpz_type,
dns_rpz_zbits_t zbits, dns_name_t *trig_name);
ISC_LANG_ENDDECLS
#endif /* DNS_RPZ_H */