3 Configuration Reference
4 =======================
6 This page lists all configuration options for dnsdist.
10 When an IPv6 IP:PORT combination is needed, the bracketed syntax from :rfc:`RFC 3986 <3986#section-3.2.2>` should be used.
11 e.g. "[2001:DB8:14::C0FF:FEE]:5300".
16 Within dnsdist several core object types exist:
18 * :class:`Server`: generated with :func:`newServer`, represents a downstream server
19 * :class:`ComboAddress`: represents an IP address and port
20 * :class:`DNSName`: represents a domain name
21 * :class:`NetmaskGroup`: represents a group of netmasks
22 * :class:`QPSLimiter`: implements a QPS-based filter
23 * :class:`SuffixMatchNode`: represents a group of domain suffixes for rapid testing of membership
24 * :class:`DNSHeader`: represents the header of a DNS packet, see :ref:`DNSHeader`
25 * :class:`ClientState`: sometimes also called Bind or Frontend, represents the addresses and ports dnsdist is listening on
27 The existence of most of these objects can mostly be ignored, unless you plan to write your own hooks and policies, but it helps to understand an expressions like:
31 getServer(0).order=12 -- set order of server 0 to 12
32 getServer(0):addPool("abuse") -- add this server to the abuse pool
34 The ``.`` means ``order`` is a data member, while the ``:`` means ``addPool`` is a member function.
39 .. function:: includeDirectory(path)
41 Include configuration files from ``path``.
43 :param str path: The directory to load configuration files from. Each file must end in ``.conf``.
45 .. function:: reloadAllCertificates()
47 .. versionadded:: 1.4.0
49 Reload all DNSCrypt and TLS certificates, along with their associated keys.
51 .. function:: setSyslogFacility(facility)
53 .. versionadded:: 1.4.0
55 Set the syslog logging facility to ``facility``.
57 :param int facility: The new facility as a numeric value. Defaults to LOG_DAEMON.
62 .. function:: addLocal(address[, options])
64 .. versionadded:: 1.2.0
66 .. versionchanged:: 1.3.0
67 Added ``cpus`` to the options.
69 .. versionchanged:: 1.4.0
70 Removed ``doTCP`` from the options. A listen socket on TCP is always created.
72 Add to the list of listen addresses.
74 :param str address: The IP Address with an optional port to listen on.
75 The default port is 53.
76 :param table options: A table with key: value pairs with listen options.
80 * ``doTCP=true``: bool - Also bind on TCP on ``address``. Removed in 1.4.0.
81 * ``reusePort=false``: bool - Set the ``SO_REUSEPORT`` socket option.
82 * ``tcpFastOpenQueueSize=0``: int - Set the TCP Fast Open queue size, enabling TCP Fast Open when available and the value is larger than 0.
83 * ``interface=""``: str - Set the network interface to use.
84 * ``cpus={}``: table - Set the CPU affinity for this listener thread, asking the scheduler to run it on a single CPU id, or a set of CPU ids. This parameter is only available if the OS provides the pthread_setaffinity_np() function.
88 addLocal('0.0.0.0:5300', { reusePort=true })
90 This will bind to both UDP and TCP on port 5300 with SO_REUSEPORT enabled.
92 .. function:: addLocal(address[[[,do_tcp], so_reuseport], tcp_fast_open_qsize])
96 Add to the list of addresses listened on.
98 :param str address: The IP Address with an optional port to listen on.
99 The default port is 53.
100 :param bool do_tcp: Also bind a TCP port on ``address``, defaults to true.
101 :param bool so_reuseport: Use ``SO_REUSEPORT`` if it is available, defaults to false
102 :param int tcp_fast_open_qsize: The size of the TCP Fast Open queue. Set to a number
103 higher than 0 to enable TCP Fast Open when available.
106 .. function:: addDOHLocal(address, [certFile(s) [, keyFile(s) [, urls [, options]]]])
108 .. versionadded:: 1.4.0
110 Listen on the specified address and TCP port for incoming DNS over HTTPS connections, presenting the specified X.509 certificate.
111 If no certificate (or key) files are specified, listen for incoming DNS over HTTP connections instead.
113 :param str address: The IP Address with an optional port to listen on.
114 The default port is 443.
115 :param str certFile(s): The path to a X.509 certificate file in PEM format, or a list of paths to such files.
116 :param str keyFile(s): The path to the private key file corresponding to the certificate, or a list of paths to such files, whose order should match the certFile(s) ones.
117 :param str-or-list urls: A base URL, or a list of base URLs, to accept queries on. Any query with a path under one of these will be treated as a DoH query. The default is /.
118 :param table options: A table with key: value pairs with listen options.
122 * ``reusePort=false``: bool - Set the ``SO_REUSEPORT`` socket option.
123 * ``tcpFastOpenQueueSize=0``: int - Set the TCP Fast Open queue size, enabling TCP Fast Open when available and the value is larger than 0.
124 * ``interface=""``: str - Set the network interface to use.
125 * ``cpus={}``: table - Set the CPU affinity for this listener thread, asking the scheduler to run it on a single CPU id, or a set of CPU ids. This parameter is only available if the OS provides the pthread_setaffinity_np() function.
126 * ``idleTimeout=30``: int - Set the idle timeout, in seconds.
127 * ``ciphers``: str - The TLS ciphers to use, in OpenSSL format. Ciphers for TLS 1.3 must be specified via ``ciphersTLS13``.
128 * ``ciphersTLS13``: str - The TLS ciphers to use for TLS 1.3, in OpenSSL format.
129 * ``serverTokens``: str - The content of the Server: HTTP header returned by dnsdist. The default is "h2o/dnsdist".
130 * ``customResponseHeaders={}``: table - Set custom HTTP header(s) returned by dnsdist.
131 * ``ocspResponses``: list - List of files containing OCSP responses, in the same order than the certificates and keys, that will be used to provide OCSP stapling responses.
132 * ``minTLSVersion``: str - Minimum version of the TLS protocol to support. Possible values are 'tls1.0', 'tls1.1', 'tls1.2' and 'tls1.3'. Default is to require at least TLS 1.0.
133 * ``numberOfTicketsKeys``: int - The maximum number of tickets keys to keep in memory at the same time. Only one key is marked as active and used to encrypt new tickets while the remaining ones can still be used to decrypt existing tickets after a rotation. Default to 5.
134 * ``ticketKeyFile``: str - The path to a file from where TLS tickets keys should be loaded, to support RFC 5077. These keys should be rotated often and never written to persistent storage to preserve forward secrecy. The default is to generate a random key. dnsdist supports several tickets keys to be able to decrypt existing sessions after the rotation.
135 * ``ticketsKeysRotationDelay``: int - Set the delay before the TLS tickets key is rotated, in seconds. Default is 43200 (12h).
136 * ``sessionTickets``: bool - Whether session resumption via session tickets is enabled. Default is true, meaning tickets are enabled.
137 * ``numberOfStoredSessions``: int - The maximum number of sessions kept in memory at the same time. Default is 20480. Setting this value to 0 disables stored session entirely.
138 * ``preferServerCiphers``: bool - Whether to prefer the order of ciphers set by the server instead of the one set by the client. Default is false, meaning that the order of the client is used.
140 .. function:: addTLSLocal(address, certFile(s), keyFile(s) [, options])
142 .. versionadded:: 1.3.0
143 .. versionchanged:: 1.3.1
144 ``certFile(s)`` and ``keyFile(s)`` parameters accept a list of files.
145 ``sessionTickets`` option added.
146 .. versionchanged:: 1.3.3
147 ``numberOfStoredSessions`` option added.
148 .. versionchanged:: 1.4.0
149 ``ciphersTLS13``, ``minTLSVersion``, ``ocspResponses`` and ``preferServerCiphers`` options added.
151 Listen on the specified address and TCP port for incoming DNS over TLS connections, presenting the specified X.509 certificate.
153 :param str address: The IP Address with an optional port to listen on.
154 The default port is 853.
155 :param str certFile(s): The path to a X.509 certificate file in PEM format, or a list of paths to such files.
156 :param str keyFile(s): The path to the private key file corresponding to the certificate, or a list of paths to such files, whose order should match the certFile(s) ones.
157 :param table options: A table with key: value pairs with listen options.
161 * ``reusePort=false``: bool - Set the ``SO_REUSEPORT`` socket option.
162 * ``tcpFastOpenQueueSize=0``: int - Set the TCP Fast Open queue size, enabling TCP Fast Open when available and the value is larger than 0.
163 * ``interface=""``: str - Set the network interface to use.
164 * ``cpus={}``: table - Set the CPU affinity for this listener thread, asking the scheduler to run it on a single CPU id, or a set of CPU ids. This parameter is only available if the OS provides the pthread_setaffinity_np() function.
165 * ``provider``: str - The TLS library to use between GnuTLS and OpenSSL, if they were available and enabled at compilation time.
166 * ``ciphers``: str - The TLS ciphers to use. The exact format depends on the provider used. When the OpenSSL provder is used, ciphers for TLS 1.3 must be specified via ``ciphersTLS13``.
167 * ``ciphersTLS13``: str - The ciphers to use for TLS 1.3, when the OpenSSL provider is used. When the GnuTLS provider is used, ``ciphers`` applies regardless of the TLS protocol and this setting is not used.
168 * ``numberOfTicketsKeys``: int - The maximum number of tickets keys to keep in memory at the same time, if the provider supports it (GnuTLS doesn't, OpenSSL does). Only one key is marked as active and used to encrypt new tickets while the remaining ones can still be used to decrypt existing tickets after a rotation. Default to 5.
169 * ``ticketKeyFile``: str - The path to a file from where TLS tickets keys should be loaded, to support RFC 5077. These keys should be rotated often and never written to persistent storage to preserve forward secrecy. The default is to generate a random key. The OpenSSL provider supports several tickets keys to be able to decrypt existing sessions after the rotation, while the GnuTLS provider only supports one key.
170 * ``ticketsKeysRotationDelay``: int - Set the delay before the TLS tickets key is rotated, in seconds. Default is 43200 (12h).
171 * ``sessionTickets``: bool - Whether session resumption via session tickets is enabled. Default is true, meaning tickets are enabled.
172 * ``numberOfStoredSessions``: int - The maximum number of sessions kept in memory at the same time. At this time this is only supported by the OpenSSL provider, as stored sessions are not supported with the GnuTLS one. Default is 20480. Setting this value to 0 disables stored session entirely.
173 * ``ocspResponses``: list - List of files containing OCSP responses, in the same order than the certificates and keys, that will be used to provide OCSP stapling responses.
174 * ``minTLSVersion``: str - Minimum version of the TLS protocol to support. Possible values are 'tls1.0', 'tls1.1', 'tls1.2' and 'tls1.3'. Default is to require at least TLS 1.0. Note that this value is ignored when the GnuTLS provider is in use, and the ``ciphers`` option should be set accordingly instead. For example, 'NORMAL:!VERS-TLS1.0:!VERS-TLS1.1' will disable TLS 1.0 and 1.1.
175 * ``preferServerCiphers``: bool - Whether to prefer the order of ciphers set by the server instead of the one set by the client. Default is false, meaning that the order of the client is used.
177 .. function:: setLocal(address[, options])
179 .. versionadded:: 1.2.0
181 Remove the list of listen addresses and add a new one.
183 :param str address: The IP Address with an optional port to listen on.
184 The default port is 53.
185 :param table options: A table with key: value pairs with listen options.
187 The options that can be set are the same as :func:`addLocal`.
189 .. function:: setLocal(address[[[,do_tcp], so_reuseport], tcp_fast_open_qsize])
191 .. deprecated:: 1.2.0
193 Remove the list of listen addresses and add a new one.
195 :param str address: The IP Address with an optional port to listen on.
196 The default port is 53.
197 :param bool do_tcp: Also bind a TCP port on ``address``, defaults to true.
198 :param bool so_reuseport: Use ``SO_REUSEPORT`` if it is available, defaults to false
199 :param int tcp_fast_open_qsize: The size of the TCP Fast Open queue. Set to a number
200 higher than 0 to enable TCP Fast Open when available.
203 Control Socket, Console and Webserver
204 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
206 .. function:: addConsoleACL(netmask)
208 .. versionadded:: 1.3.0
210 Add a netmask to the existing console ACL, allowing remote clients to connect to the console. Please make sure that encryption
211 has been enabled with :func:`setKey` before doing so. The default is to only allow 127.0.0.1/8 and ::1/128.
213 :param str netmask: A CIDR netmask, e.g. ``"192.0.2.0/24"``. Without a subnetmask, only the specific address is allowed.
215 .. function:: controlSocket(address)
217 Bind to ``addr`` and listen for a connection for the console. Since 1.3.0 only connections from local users are allowed
218 by default, :func:`addConsoleACL` and :func:`setConsoleACL` can be used to enable remote connections. Please make sure
219 that encryption has been enabled with :func:`setKey` before doing so. Enabling encryption is also strongly advised for
220 local connections, since not enabling it allows any local user to connect to the console.
222 :param str address: An IP address with optional port. By default, the port is 5199.
224 .. function:: inClientStartup()
226 Returns true while the console client is parsing the configuration.
228 .. function:: makeKey()
230 Generate and print an encryption key.
232 .. function:: setConsoleConnectionsLogging(enabled)
234 .. versionadded:: 1.2.0
236 Whether to log the opening and closing of console connections.
238 :param bool enabled: Default to true.
240 .. function:: setKey(key)
242 Use ``key`` as shared secret between the client and the server
244 :param str key: An encoded key, as generated by :func:`makeKey`
246 .. function:: setConsoleACL(netmasks)
248 .. versionadded:: 1.3.0
250 Remove the existing console ACL and add the netmasks from the table, allowing remote clients to connect to the console. Please make sure that encryption
251 has been enabled with :func:`setKey` before doing so.
253 :param {str} netmasks: A table of CIDR netmask, e.g. ``{"192.0.2.0/24", "2001:DB8:14::/56"}``. Without a subnetmask, only the specific address is allowed.
255 .. function:: showConsoleACL()
257 Print a list of all netmasks allowed to connect to the console.
259 .. function:: testCrypto()
261 Test the crypto code, will report errors when something is not ok.
263 .. function:: setConsoleOutputMaxMsgSize(size)
265 .. versionadded:: 1.3.3
267 Set the maximum size in bytes of a single console message, default set to 10 MB.
269 :param int size: The new maximum size.
271 Webserver configuration
272 ~~~~~~~~~~~~~~~~~~~~~~~
274 .. function:: webserver(listen_address, password[, apikey[, custom_headers]])
276 Launch the :doc:`../guides/webserver` with statistics and the API.
278 :param str listen_address: The IP address and Port to listen on
279 :param str password: The password required to access the webserver
280 :param str apikey: The key required to access the API
281 :param {[str]=str,...} custom_headers: Allows setting custom headers and removing the defaults
283 .. function:: setAPIWritable(allow [,dir])
285 Allow modifications via the API.
286 Optionally saving these changes to disk.
287 Modifications done via the API will not be written to the configuration by default and will not persist after a reload
289 :param bool allow: Set to true to allow modification through the API
290 :param str dir: A valid directory where the configuration files will be written by the API.
292 .. function:: setWebserverConfig(options)
294 .. versionadded:: 1.3.3
296 Setup webserver configuration. See :func:`webserver`.
298 :param table options: A table with key: value pairs with webserver options.
302 * ``password=newPassword``: string - Changes the API password
303 * ``apikey=newKey``: string - Changes the API Key (set to an empty string do disable it)
304 * ``custom_headers={[str]=str,...}``: map of string - Allows setting custom headers and removing the defaults.
309 .. function:: addACL(netmask)
311 Add a netmask to the existing ACL controlling which clients can send UDP, TCP, DNS over TLS and DNS over HTTPS queries. See :ref:`ACL` for more information.
313 :param str netmask: A CIDR netmask, e.g. ``"192.0.2.0/24"``. Without a subnetmask, only the specific address is allowed.
315 .. function:: setACL(netmasks)
317 Remove the existing ACL and add the netmasks from the table of those allowed to send UDP, TCP, DNS over TLS and DNS over HTTPS queries. See :ref:`ACL` for more information.
319 :param {str} netmasks: A table of CIDR netmask, e.g. ``{"192.0.2.0/24", "2001:DB8:14::/56"}``. Without a subnetmask, only the specific address is allowed.
321 .. function:: showACL()
323 Print a list of all netmasks allowed to send queries over UDP, TCP, DNS over TLS and DNS over HTTPS. See :ref:`ACL` for more information.
328 .. function:: setECSOverride(bool)
330 When ``useClientSubnet`` in :func:`newServer` is set and dnsdist adds an EDNS Client Subnet Client option to the query, override an existing option already present in the query, if any
332 :param bool: Whether to override an existing EDNS Client Subnet option present in the query. Defaults to false
334 .. function:: setECSSourcePrefixV4(prefix)
336 When ``useClientSubnet`` in :func:`newServer` is set and dnsdist adds an EDNS Client Subnet Client option to the query, truncate the requestors IPv4 address to ``prefix`` bits
338 :param int prefix: The prefix length
340 .. function:: setECSSourcePrefixV6(prefix)
342 When ``useClientSubnet`` in :func:`newServer` is set and dnsdist adds an EDNS Client Subnet Client option to the query, truncate the requestor's IPv6 address to bits
344 :param int prefix: The prefix length
349 .. function:: setRingBuffersLockRetries(num)
351 .. versionadded:: 1.3.0
353 Set the number of shards to attempt to lock without blocking before giving up and simply blocking while waiting for the next shard to be available
355 :param int num: The maximum number of attempts. Defaults to 5 if there is more than one shard, 0 otherwise.
357 .. function:: setRingBuffersSize(num [, numberOfShards])
359 .. versionchanged:: 1.3.0
360 ``numberOfShards`` optional parameter added.
362 Set the capacity of the ringbuffers used for live traffic inspection to ``num``, and the number of shards to ``numberOfShards`` if specified.
364 :param int num: The maximum amount of queries to keep in the ringbuffer. Defaults to 10000
365 :param int numberOfShards: the number of shards to use to limit lock contention. Defaults to 1
370 .. function:: newServer(server_string)
371 newServer(server_table)
373 .. versionchanged:: 1.3.0
374 Added ``checkClass``, ``sockets`` and ``checkFunction`` to server_table.
376 .. versionchanged:: 1.4.0
377 Added ``checkInterval``, ``checkTimeout`` and ``rise`` to server_table.
379 Add a new backend server. Call this function with either a string::
382 "IP:PORT" -- IP and PORT of the backend server
388 address="IP:PORT", -- IP and PORT of the backend server (mandatory)
389 id=STRING, -- Use a pre-defined UUID instead of a random one
390 qps=NUM, -- Limit the number of queries per second to NUM, when using the `firstAvailable` policy
391 order=NUM, -- The order of this server, used by the `leastOutstanding` and `firstAvailable` policies
392 weight=NUM, -- The weight of this server, used by the `wrandom`, `whashed` and `chashed` policies, default: 1
393 -- Supported values are a minimum of 1, and a maximum of 2147483647.
394 pool=STRING|{STRING}, -- The pools this server belongs to (unset or empty string means default pool) as a string or table of strings
395 retries=NUM, -- The number of TCP connection attempts to the backend, for a given query
396 tcpConnectTimeout=NUM, -- The timeout (in seconds) of a TCP connection attempt
397 tcpSendTimeout=NUM, -- The timeout (in seconds) of a TCP write attempt
398 tcpRecvTimeout=NUM, -- The timeout (in seconds) of a TCP read attempt
399 tcpFastOpen=BOOL, -- Whether to enable TCP Fast Open
400 ipBindAddrNoPort=BOOL, -- Whether to enable IP_BIND_ADDRESS_NO_PORT if available, default: true
401 name=STRING, -- The name associated to this backend, for display purpose
402 checkClass=NUM, -- Use NUM as QCLASS in the health-check query, default: DNSClass.IN
403 checkName=STRING, -- Use STRING as QNAME in the health-check query, default: "a.root-servers.net."
404 checkType=STRING, -- Use STRING as QTYPE in the health-check query, default: "A"
405 checkFunction=FUNCTION,-- Use this function to dynamically set the QNAME, QTYPE and QCLASS to use in the health-check query (see :ref:`Healthcheck`)
406 checkTimeout=NUM, -- The timeout (in milliseconds) of a health-check query, default: 1000 (1s)
407 setCD=BOOL, -- Set the CD (Checking Disabled) flag in the health-check query, default: false
408 maxCheckFailures=NUM, -- Allow NUM check failures before declaring the backend down, default: 1
409 checkInterval=NUM -- The time in seconds between health checks
410 mustResolve=BOOL, -- Set to true when the health check MUST return a RCODE different from NXDomain, ServFail and Refused. Default is false, meaning that every RCODE except ServFail is considered valid
411 useClientSubnet=BOOL, -- Add the client's IP address in the EDNS Client Subnet option when forwarding the query to this backend
412 source=STRING, -- The source address or interface to use for queries to this backend, by default this is left to the kernel's address selection
413 -- The following formats are supported:
414 -- "address", e.g. "192.0.2.2"
415 -- "interface name", e.g. "eth0"
416 -- "address@interface", e.g. "192.0.2.2@eth0"
417 addXPF=NUM, -- Add the client's IP address and port to the query, along with the original destination address and port,
418 -- using the experimental XPF record from `draft-bellis-dnsop-xpf <https://datatracker.ietf.org/doc/draft-bellis-dnsop-xpf/>`_ and the specified option code. Default is disabled (0)
419 sockets=NUM, -- Number of sockets (and thus source ports) used toward the backend server, defaults to a single one
420 disableZeroScope=BOOL, -- Disable the EDNS Client Subnet 'zero scope' feature, which does a cache lookup for an answer valid for all subnets (ECS scope of 0) before adding ECS information to the query and doing the regular lookup
421 rise=NUM -- Require NUM consecutive successful checks before declaring the backend up, default: 1
424 :param str server_string: A simple IP:PORT string.
425 :param table server_table: A table with at least a 'name' key
427 .. function:: getServer(index) -> Server
429 Get a :class:`Server`
431 :param int index: The number of the server (as seen in :func:`showServers`).
432 :returns: The :class:`Server` object or nil
434 .. function:: getServers()
436 Returns a table with all defined servers.
438 .. function:: rmServer(index)
441 Remove a backend server.
443 :param int index: The number of the server (as seen in :func:`showServers`).
444 :param Server server: A :class:`Server` object as returned by e.g. :func:`getServer`.
448 A server object returned by :func:`getServer` can be manipulated with these functions.
452 This object represents a backend server. It has several methods.
454 .. method:: Server:addPool(pool)
456 Add this server to a pool.
458 :param str pool: The pool to add the server to
460 .. method:: Server:getName() -> string
462 Get the name of this server.
464 :returns: The name of the server, or an empty string if it does not have one
466 .. method:: Server:getNameWithAddr() -> string
468 Get the name plus IP address and port of the server
470 :returns: A string containing the server name if any plus the server address and port
472 .. method:: Server:getOutstanding() -> int
474 Get the number of outstanding queries for this server.
476 :returns: The number of outstanding queries
478 .. method:: Server:isUp() -> bool
480 Returns the up status of the server
482 :returns: true when the server is up, false otherwise
484 .. method:: Server:rmPool(pool)
486 Removes the server from the named pool
488 :param str pool: The pool to remove the server from
490 .. method:: Server:setAuto([status])
492 .. versionchanged:: 1.3.0
493 ``status`` optional parameter added.
495 Set the server in the default auto state.
496 This will enable health check queries that will set the server ``up`` and ``down`` appropriately.
498 :param bool status: Set the initial status of the server to ``up`` (true) or ``down`` (false) instead of using the last known status
500 .. method:: Server:setQPS(limit)
502 Limit the queries per second for this server.
504 :param int limit: The maximum number of queries per second
506 .. method:: Server:setDown()
508 Set the server in an ``DOWN`` state.
509 The server will not receive queries and the health checks are disabled
511 .. method:: Server:setUp()
513 Set the server in an ``UP`` state.
514 This server will still receive queries and health checks are disabled
516 Apart from the functions, a :class:`Server` object has these attributes:
518 .. attribute:: Server.name
520 The name of the server
522 .. attribute:: Server.upStatus
524 Whether or not this server is up or down
526 .. attribute:: Server.order
528 The order of the server
530 .. attribute:: Server.weight
532 The weight of the server
537 :class:`Server`\ s can be part of any number of pools.
538 Pools are automatically created when a server is added to a pool (with :func:`newServer`), or can be manually created with :func:`addPool`.
540 .. function:: addPool(name) -> ServerPool
542 Returns a :class:`ServerPool`.
544 :param string name: The name of the pool to create
546 .. function:: getPool(name) -> ServerPool
548 Returns a :class:`ServerPool` or nil.
550 :param string name: The name of the pool
552 .. function:: getPoolServers(name) -> [ Server ]
554 Returns a list of :class:`Server`\ s or nil.
556 :param string name: The name of the pool
558 .. function:: showPools()
560 Display the name, associated cache, server policy and associated servers for every pool.
562 .. class:: ServerPool
564 This represents the pool where zero or more servers are part of.
566 .. method:: ServerPool:getCache() -> PacketCache
568 Returns the :class:`PacketCache` for this pool or nil.
570 .. method:: ServerPool:getECS()
572 .. versionadded:: 1.3.0
574 Whether dnsdist will add EDNS Client Subnet information to the query before looking up into the cache,
575 when all servers from this pool are down. For more information see :meth:`ServerPool:setECS`.
577 .. method:: ServerPool:setCache(cache)
579 Adds ``cache`` as the pool's cache.
581 :param PacketCache cache: The new cache to add to the pool
583 .. method:: ServerPool:unsetCache()
585 Removes the cache from this pool.
587 .. method:: ServerPool:setECS()
589 .. versionadded:: 1.3.0
591 Set to true if dnsdist should add EDNS Client Subnet information to the query before looking up into the cache,
592 when all servers from this pool are down. If at least one server is up, the preference of the
593 selected server is used, this parameter is only useful if all the backends in this pool are down
594 and have EDNS Client Subnet enabled, since the queries in the cache will have been inserted with
595 ECS information. Default is false.
600 A Pool can have a packet cache to answer queries directly instead of going to the backend.
601 See :doc:`../guides/cache` for a how to.
603 .. function:: newPacketCache(maxEntries[, maxTTL=86400[, minTTL=0[, temporaryFailureTTL=60[, staleTTL=60[, dontAge=false[, numberOfShards=1[, deferrableInsertLock=true[, maxNegativeTTL=3600[, parseECS=false]]]]]]]) -> PacketCache
605 .. versionchanged:: 1.3.0
606 ``numberOfShards`` and ``deferrableInsertLock`` parameters added.
608 .. versionchanged:: 1.3.1
609 ``maxNegativeTTL`` and ``parseECS`` parameters added.
611 .. deprecated:: 1.4.0
613 Creates a new :class:`PacketCache` with the settings specified.
615 :param int maxEntries: The maximum number of entries in this cache
616 :param int maxTTL: Cap the TTL for records to his number
617 :param int minTTL: Don't cache entries with a TTL lower than this
618 :param int temporaryFailureTTL: On a SERVFAIL or REFUSED from the backend, cache for this amount of seconds
619 :param int staleTTL: When the backend servers are not reachable, and global configuration ``setStaleCacheEntriesTTL`` is set appropriately, TTL that will be used when a stale cache entry is returned
620 :param bool dontAge: Don't reduce TTLs when serving from the cache. Use this when :program:`dnsdist` fronts a cluster of authoritative servers
621 :param int numberOfShards: Number of shards to divide the cache into, to reduce lock contention
622 :param bool deferrableInsertLock: Whether the cache should give up insertion if the lock is held by another thread, or simply wait to get the lock
623 :param int maxNegativeTTL: Cache a NXDomain or NoData answer from the backend for at most this amount of seconds, even if the TTL of the SOA record is higher
624 :param bool parseECS: Whether any EDNS Client Subnet option present in the query should be extracted and stored to be able to detect hash collisions involving queries with the same qname, qtype and qclass but a different incoming ECS value. Enabling this option adds a parsing cost and only makes sense if at least one backend might send different responses based on the ECS value, so it's disabled by default
626 .. function:: newPacketCache(maxEntries, [options]) -> PacketCache
628 .. versionadded:: 1.4.0
630 Creates a new :class:`PacketCache` with the settings specified.
632 :param int maxEntries: The maximum number of entries in this cache
636 * ``deferrableInsertLock=true``: bool - Whether the cache should give up insertion if the lock is held by another thread, or simply wait to get the lock.
637 * ``dontAge=false``: bool - Don't reduce TTLs when serving from the cache. Use this when :program:`dnsdist` fronts a cluster of authoritative servers.
638 * ``keepStaleData=false``: bool - Whether to suspend the removal of expired entries from the cache when there is no backend available in at least one of the pools using this cache.
639 * ``maxNegativeTTL=3600``: int - Cache a NXDomain or NoData answer from the backend for at most this amount of seconds, even if the TTL of the SOA record is higher.
640 * ``maxTTL=86400``: int - Cap the TTL for records to his number.
641 * ``minTTL=0``: int - Don't cache entries with a TTL lower than this.
642 * ``numberOfShards=1``: int - Number of shards to divide the cache into, to reduce lock contention.
643 * ``parseECS=false``: bool - Whether any EDNS Client Subnet option present in the query should be extracted and stored to be able to detect hash collisions involving queries with the same qname, qtype and qclass but a different incoming ECS value. Enabling this option adds a parsing cost and only makes sense if at least one backend might send different responses based on the ECS value, so it's disabled by default.
644 * ``staleTTL=60``: int - When the backend servers are not reachable, and global configuration ``setStaleCacheEntriesTTL`` is set appropriately, TTL that will be used when a stale cache entry is returned.
645 * ``temporaryFailureTTL=60``: int - On a SERVFAIL or REFUSED from the backend, cache for this amount of seconds..
647 .. class:: PacketCache
649 Represents a cache that can be part of :class:`ServerPool`.
651 .. method:: PacketCache:dump(fname)
653 .. versionadded:: 1.3.1
655 Dump a summary of the cache entries to a file.
657 :param str fname: The path to a file where the cache summary should be dumped. Note that if the target file already exists, it will not be overwritten.
659 .. method:: PacketCache:expunge(n)
661 Remove entries from the cache, leaving at most ``n`` entries
663 :param int n: Number of entries to keep
665 .. method:: PacketCache:expungeByName(name [, qtype=DNSQType.ANY[, suffixMatch=false]])
667 .. versionchanged:: 1.2.0
668 ``suffixMatch`` parameter added.
670 Remove entries matching ``name`` and type from the cache.
672 :param DNSName name: The name to expunge
673 :param int qtype: The type to expunge, can be a pre-defined :ref:`DNSQType`
674 :param bool suffixMatch: When set to true, remove al entries under ``name``
676 .. method:: PacketCache:getStats()
678 .. versionadded:: 1.4.0
680 Return the cache stats (number of entries, hits, misses, deferred lookups, deferred inserts, lookup collisions, insert collisions and TTL too shorts) as a Lua table.
682 .. method:: PacketCache:isFull() -> bool
684 Return true if the cache has reached the maximum number of entries.
686 .. method:: PacketCache:printStats()
688 Print the cache stats (number of entries, hits, misses, deferred lookups, deferred inserts, lookup collisions, insert collisions and TTL too shorts).
690 .. method:: PacketCache:purgeExpired(n)
692 Remove expired entries from the cache until there is at most ``n`` entries remaining in the cache.
694 :param int n: Number of entries to keep
696 .. method:: PacketCache:toString() -> string
698 Return the number of entries in the Packet Cache, and the maximum number of entries
703 Also called frontend or bind, the Client State object returned by :func:`getBind` and listed with :func:`showBinds` represents an address and port dnsdist is listening on.
705 .. function:: getBind(index) -> ClientState
707 Return a :class:`ClientState` object.
709 :param int index: The object index
711 ClientState functions
712 ~~~~~~~~~~~~~~~~~~~~~
714 .. class:: ClientState
716 This object represents an address and port dnsdist is listening on. When ``reuseport`` is in use, several ClientState objects can be present for the same address and port.
718 .. method:: ClientState:attachFilter(filter)
720 Attach a BPF filter to this frontend.
722 :param BPFFilter filter: The filter to attach to this frontend
724 .. method:: ClientState:detachFilter()
726 Remove the BPF filter associated to this frontend, if any.
728 .. method:: ClientState:toString() -> string
730 Return the address and port this frontend is listening on.
732 :returns: The address and port this frontend is listening on
734 .. attribute:: ClientState.muted
736 If set to true, queries received on this frontend will be normally processed and sent to a backend if needed, but no response will be ever be sent to the client over UDP. TCP queries are processed normally and responses sent to the client.
738 Status, Statistics and More
739 ---------------------------
741 .. function:: dumpStats()
743 Print all statistics dnsdist gathers
745 .. function:: getDOHFrontend(idx)
747 .. versionadded:: 1.4.0
749 Return the DOHFrontend object for the DNS over HTTPS bind of index ``idx``.
751 .. function:: getTLSContext(idx)
753 .. versionadded:: 1.3.0
755 Return the TLSContext object for the context of index ``idx``.
757 .. function:: getTLSFrontend(idx)
759 .. versionadded:: 1.3.1
761 Return the TLSFrontend object for the TLS bind of index ``idx``.
763 .. function:: grepq(selector[, num])
764 grepq(selectors[, num])
766 Prints the last ``num`` queries matching ``selector`` or ``selectors``.
770 * a netmask (e.g. '192.0.2.0/24')
771 * a DNS name (e.g. 'dnsdist.org')
772 * a response time (e.g. '100ms')
774 :param str selector: Select queries based on this property.
775 :param {str} selectors: A lua table of selectors. Only queries matching all selectors are shown
776 :param int num: Show a maximum of ``num`` recent queries, default is 10.
778 .. function:: setVerboseHealthChecks(verbose)
780 Set whether health check errors should be logged. This is turned off by default.
782 :param bool verbose: Set to true if you want to enable health check errors logging
784 .. function:: showBinds()
786 Print a list of all the current addresses and ports dnsdist is listening on, also called ``frontends``
788 .. function:: showDOHFrontends()
790 .. versionadded:: 1.4.0
792 Print the list of all availables DNS over HTTPS frontends.
794 .. function:: showDOHResponseCodes()
796 .. versionadded:: 1.4.0
798 Print the HTTP response codes statistics for all availables DNS over HTTPS frontends.
800 .. function:: showResponseLatency()
802 Show a plot of the response time latency distribution
804 .. function:: showServers([options])
806 .. versionchanged:: 1.4.0
807 ``options`` optional parameter added
809 This function shows all backend servers currently configured and some statistics.
810 These statics have the following fields:
812 * ``#`` - The number of the server, can be used as the argument for :func:`getServer`
813 * ``UUID`` - The UUID of the backend. Can be set with the ``id`` option of :func:`newServer`
814 * ``Address`` - The IP address and port of the server
815 * ``State`` - The current state of the server
816 * ``Qps`` - Current number of queries per second
817 * ``Qlim`` - Configured maximum number of queries per second
818 * ``Ord`` - The order number of the server
819 * ``Wt`` - The weight of the server
820 * ``Queries`` - Total amount of queries sent to this server
821 * ``Drops`` - Number of queries that were dropped by this server
822 * ``Drate`` - Number of queries dropped per second by this server
823 * ``Lat`` - The latency of this server in milliseconds
824 * ``Pools`` - The pools this server belongs to
826 :param table options: A table with key: value pairs with display options.
830 * ``showUUIDs=false``: bool - Whether to display the UUIDs, defaults to false.
832 .. function:: showTCPStats()
834 Show some statistics regarding TCP
836 .. function:: showTLSContexts()
838 .. versionadded:: 1.3.0
840 Print the list of all availables DNS over TLS contexts.
842 .. function:: showVersion()
844 Print the version of dnsdist
846 .. function:: topBandwidth([num])
848 Print the top ``num`` clients that consume the most bandwidth.
850 :param int num: Number to show, defaults to 10.
852 .. function:: topClients([num])
854 Print the top ``num`` clients sending the most queries over length of ringbuffer
856 :param int num: Number to show, defaults to 10.
858 .. function:: topQueries([num[, labels]])
860 Print the ``num`` most popular QNAMEs from queries.
861 Optionally grouped by the rightmost ``labels`` DNS labels.
863 :param int num: Number to show, defaults to 10
864 :param int label: Number of labels to cut down to
866 .. function:: topResponses([num[, rcode[, labels]]])
868 Print the ``num`` most seen responses with an RCODE of ``rcode``.
869 Optionally grouped by the rightmost ``labels`` DNS labels.
871 :param int num: Number to show, defaults to 10
872 :param int rcode: :ref:`Response code <DNSRCode>`, defaults to 0 (No Error)
873 :param int label: Number of labels to cut down to
875 .. function:: topSlow([num[, limit[, labels]]])
877 Print the ``num`` slowest queries that are slower than ``limit`` milliseconds.
878 Optionally grouped by the rightmost ``labels`` DNS labels.
880 :param int num: Number to show, defaults to 10
881 :param int limit: Show queries slower than this amount of milliseconds, defaults to 2000
882 :param int label: Number of labels to cut down to
889 .. function:: addDynBlocks(addresses, message[, seconds=10[, action]])
891 .. versionchanged:: 1.2.0
892 ``action`` parameter added.
894 Block a set of addresses with ``message`` for (optionally) a number of seconds.
895 The default number of seconds to block for is 10.
897 :param addresses: set of Addresses as returned by an exceed function
898 :param string message: The message to show next to the blocks
899 :param int seconds: The number of seconds this block to expire
900 :param int action: The action to take when the dynamic block matches, see :ref:`here <DNSAction>`. (default to DNSAction.None, meaning the one set with :func:`setDynBlocksAction` is used)
902 Please see the documentation for :func:`setDynBlocksAction` to confirm which actions are supported by the action paramater.
904 .. function:: clearDynBlocks()
906 Remove all current dynamic blocks.
908 .. function:: showDynBlocks()
910 List all dynamic blocks in effect.
912 .. function:: setDynBlocksAction(action)
914 .. versionchanged:: 1.3.3
915 ``DNSAction.NXDomain`` action added.
917 Set which action is performed when a query is blocked.
918 Only DNSAction.Drop (the default), DNSAction.NoOp, DNSAction.NXDomain, DNSAction.Refused, DNSAction.Truncate and DNSAction.NoRecurse are supported.
922 Getting addresses that exceeded parameters
923 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
925 .. function:: exceedServFails(rate, seconds)
927 Get set of addresses that exceed ``rate`` servfails/s over ``seconds`` seconds
929 :param int rate: Number of Servfails per second to exceed
930 :param int seconds: Number of seconds the rate has been exceeded
932 .. function:: exceedNXDOMAINs(rate, seconds)
934 get set of addresses that exceed ``rate`` NXDOMAIN/s over ``seconds`` seconds
936 :param int rate: Number of NXDOMAIN per second to exceed
937 :param int seconds: Number of seconds the rate has been exceeded
939 .. function:: exceedRespByterate(rate, seconds)
941 get set of addresses that exceeded ``rate`` bytes/s answers over ``seconds`` seconds
943 :param int rate: Number of bytes per second to exceed
944 :param int seconds: Number of seconds the rate has been exceeded
946 .. function:: exceedQRate(rate, seconds)
948 Get set of address that exceed ``rate`` queries/s over ``seconds`` seconds
950 :param int rate: Number of queries per second to exceed
951 :param int seconds: Number of seconds the rate has been exceeded
953 .. function:: exceedQTypeRate(type, rate, seconds)
955 Get set of address that exceed ``rate`` queries/s for queries of QType ``type`` over ``seconds`` seconds
957 :param int type: QType
958 :param int rate: Number of QType queries per second to exceed
959 :param int seconds: Number of seconds the rate has been exceeded
964 Instead of using several `exceed*()` lines, dnsdist 1.3.0 introduced a new `DynBlockRulesGroup` object
965 which can be used to group dynamic block rules.
967 See :doc:`../guides/dynblocks` for more information about the case where using a `DynBlockRulesGroup` might be
968 faster than the existing rules.
970 .. function:: dynBlockRulesGroup() -> DynBlockRulesGroup
972 .. versionadded:: 1.3.0
974 Creates a new :class:`DynBlockRulesGroup` object.
976 .. class:: DynBlockRulesGroup
978 Represents a group of dynamic block rules.
980 .. method:: DynBlockRulesGroup:setQueryRate(rate, seconds, reason, blockingTime [, action [, warningRate]])
982 .. versionchanged:: 1.3.3
983 ``warningRate`` parameter added.
985 Adds a query rate-limiting rule, equivalent to:
987 addDynBlocks(exceedQRate(rate, seconds), reason, blockingTime, action)
990 :param int rate: Number of queries per second to exceed
991 :param int seconds: Number of seconds the rate has been exceeded
992 :param string reason: The message to show next to the blocks
993 :param int blockingTime: The number of seconds this block to expire
994 :param int action: The action to take when the dynamic block matches, see :ref:`here <DNSAction>`. (default to the one set with :func:`setDynBlocksAction`)
995 :param int warningRate: If set to a non-zero value, the rate above which a warning message will be issued and a no-op block inserted
997 .. method:: DynBlockRulesGroup:setRCodeRate(rcode, rate, seconds, reason, blockingTime [, action [, warningRate]])
999 .. versionchanged:: 1.3.3
1000 ``warningRate`` parameter added.
1002 Adds a rate-limiting rule for responses of code ``rcode``, equivalent to:
1004 addDynBlocks(exceedServfails(rcode, rate, seconds), reason, blockingTime, action)
1007 :param int rcode: The response code
1008 :param int rate: Number of responses per second to exceed
1009 :param int seconds: Number of seconds the rate has been exceeded
1010 :param string reason: The message to show next to the blocks
1011 :param int blockingTime: The number of seconds this block to expire
1012 :param int action: The action to take when the dynamic block matches, see :ref:`here <DNSAction>`. (default to the one set with :func:`setDynBlocksAction`)
1013 :param int warningRate: If set to a non-zero value, the rate above which a warning message will be issued and a no-op block inserted
1015 .. method:: DynBlockRulesGroup:setQTypeRate(qtype, rate, seconds, reason, blockingTime [, action [, warningRate]])
1017 .. versionchanged:: 1.3.3
1018 ``warningRate`` parameter added.
1020 Adds a rate-limiting rule for queries of type ``qtype``, equivalent to:
1022 addDynBlocks(exceedQTypeRate(type, rate, seconds), reason, blockingTime, action)
1025 :param int qtype: The qtype
1026 :param int rate: Number of queries per second to exceed
1027 :param int seconds: Number of seconds the rate has been exceeded
1028 :param string reason: The message to show next to the blocks
1029 :param int blockingTime: The number of seconds this block to expire
1030 :param int action: The action to take when the dynamic block matches, see :ref:`here <DNSAction>`. (default to the one set with :func:`setDynBlocksAction`)
1031 :param int warningRate: If set to a non-zero value, the rate above which a warning message will be issued and a no-op block inserted
1033 .. method:: DynBlockRulesGroup:setResponseByteRate(rate, seconds, reason, blockingTime [, action [, warningRate]])
1035 .. versionchanged:: 1.3.3
1036 ``warningRate`` parameter added.
1038 Adds a bandwidth rate-limiting rule for responses, equivalent to:
1040 addDynBlocks(exceedRespByterate(rate, seconds), reason, blockingTime, action)
1043 :param int rate: Number of bytes per second to exceed
1044 :param int seconds: Number of seconds the rate has been exceeded
1045 :param string reason: The message to show next to the blocks
1046 :param int blockingTime: The number of seconds this block to expire
1047 :param int action: The action to take when the dynamic block matches, see :ref:`here <DNSAction>`. (default to the one set with :func:`setDynBlocksAction`)
1048 :param int warningRate: If set to a non-zero value, the rate above which a warning message will be issued and a no-op block inserted
1050 .. method:: DynBlockRulesGroup:apply()
1052 Walk the in-memory query and response ring buffers and apply the configured rate-limiting rules, adding dynamic blocks when the limits have been exceeded.
1054 .. method:: DynBlockRulesGroup:setQuiet(quiet)
1056 .. versionadded:: 1.4.0
1058 Set whether newly blocked clients or domains should be logged.
1060 :param bool quiet: True means that insertions will not be logged, false that they will. Default is false.
1062 .. method:: DynBlockRulesGroup:excludeRange(netmasks)
1064 .. versionadded:: 1.3.1
1066 Exclude this range, or list of ranges, meaning that no dynamic block will ever be inserted for clients in that range. Default to empty, meaning rules are applied to all ranges. When used in combination with :meth:`DynBlockRulesGroup:includeRange`, the more specific entry wins.
1068 :param int netmasks: A netmask, or list of netmasks, as strings, like for example "192.0.2.1/24"
1070 .. method:: DynBlockRulesGroup:includeRange(netmasks)
1072 .. versionadded:: 1.3.1
1074 Include this range, or list of ranges, meaning that rules will be applied to this range. When used in combination with :meth:`DynBlockRulesGroup:excludeRange`, the more specific entry wins.
1076 :param int netmasks: A netmask, or list of netmasks, as strings, like for example "192.0.2.1/24"
1078 .. method:: DynBlockRulesGroup:toString()
1080 .. versionadded:: 1.3.1
1082 Return a string describing the rules and range exclusions of this DynBlockRulesGroup.
1087 A SuffixMatchNode can be used to quickly check whether a given name belongs to a set or not. This is achieved
1088 using an efficient tree structure based on DNS labels, making lookups cheap.
1089 Be careful that Suffix Node matching will match for any sub-domain, regardless of the depth, under the name added to the set. For example,
1090 if 'example.com.' is added to the set, 'www.example.com.' and 'sub.www.example.com.' will match as well.
1091 If you are looking for exact name matching, your might want to consider using a :class:`DNSNameSet` instead.
1093 .. function:: newSuffixMatchNode()
1095 Creates a new :class:`SuffixMatchNode`.
1097 .. class:: SuffixMatchNode
1099 Represent a set of DNS suffixes for quick matching.
1101 .. method:: SuffixMatchNode:add(name)
1103 .. versionchanged:: 1.4.0
1104 This method now accepts strings, lists of DNSNames and lists of strings.
1106 Add a suffix to the current set.
1108 :param DNSName name: The suffix to add to the set.
1109 :param string name: The suffix to add to the set.
1110 :param table name: The suffixes to add to the set. Elements of the table should be of the same type, either DNSName or string.
1112 .. method:: SuffixMatchNode:check(name) -> bool
1114 Return true if the given name is a sub-domain of one of those in the set, and false otherwise.
1116 :param DNSName name: The name to test against the set.
1121 .. function:: maintenance()
1123 If this function exists, it is called every second to so regular tasks.
1124 This can be used for e.g. :doc:`Dynamic Blocks <../guides/dynblocks>`.
1126 .. function:: setAllowEmptyResponse()
1128 .. versionadded:: 1.4.0
1130 Set to true (defaults to false) to allow empty responses (qdcount=0) with a NoError or NXDomain rcode (default) from backends. dnsdist drops these responses by default because it can't match them against the initial query since they don't contain the qname, qtype and qclass, and therefore the risk of collision is much higher than with regular responses.
1132 .. function:: makeIPCipherKey(password) -> string
1134 .. versionadded:: 1.4.0
1136 Hashes the password to generate a 16-byte key that can be used to pseudonymize IP addresses with IP cipher.
1138 .. function:: generateOCSPResponse(pathToServerCertificate, pathToCACertificate, pathToCAPrivateKey, outputFile, numberOfDaysOfValidity, numberOfMinutesOfValidity)
1140 .. versionadded:: 1.4.0
1142 When a local PKI is used to issue the certificate, or for testing purposes, :func:`generateOCSPResponse` can be used to generate an OCSP response file for a certificate, using the certificate and private key of the certification authority that signed that certificate.
1143 The resulting file can be directly used with the :func:`addDOHLocal` or the :func:`addTLSLocal` functions.
1145 :param string pathToServerCertificate: Path to a file containing the certificate used by the server.
1146 :param string pathToCACertificate: Path to a file containing the certificate of the certification authority that was used to sign the server certificate.
1147 :param string pathToCAPrivateKey: Path to a file containing the private key corresponding to the certification authority certificate.
1148 :param string outputFile: Path to a file where the resulting OCSP response will be written to.
1149 :param int numberOfDaysOfValidity: Number of days this OCSP response should be valid.
1150 :param int numberOfMinutesOfValidity: Number of minutes this OCSP response should be valid, in addition to the number of days.
1155 .. class:: DOHFrontend
1157 .. versionadded:: 1.4.0
1159 This object represents an address and port dnsdist is listening on for DNS over HTTPS queries.
1161 .. method:: DOHFrontend:loadTicketsKeys(ticketsKeysFile)
1163 Load new tickets keys from the selected file, replacing the existing ones. These keys should be rotated often and never written to persistent storage to preserve forward secrecy. The default is to generate a random key. dnsdist supports several tickets keys to be able to decrypt existing sessions after the rotation.
1165 :param str ticketsKeysFile: The path to a file from where TLS tickets keys should be loaded.
1167 .. method:: DOHFrontend:reloadCertificates()
1169 Reload the current TLS certificate and key pairs.
1171 .. method:: DOHFrontend:rotateTicketsKey()
1173 Replace the current TLS tickets key by a new random one.
1175 .. method:: DOHFrontend:setResponsesMap(rules)
1177 Set a list of HTTP response rules allowing to intercept HTTP queries very early, before the DNS payload has been processed, and send custom responses including error pages, redirects and static content.
1179 :param list of DOHResponseMapEntry objects rules: A list of DOHResponseMapEntry objects, obtained with :func:`newDOHResponseMapEntry`.
1182 .. function:: newDOHResponseMapEntry(regex, status, content [, headers]) -> DOHResponseMapEntry
1184 .. versionadded:: 1.4.0
1186 Return a DOHResponseMapEntry that can be used with :meth:`DOHFrontend.setResponsesMap`. Every query whose path matches the regular expression supplied in ``regex`` will be immediately answered with a HTTP response.
1187 The status of the HTTP response will be the one supplied by ``status``, and the content set to the one supplied by ``content``, except if the status is a redirection (3xx) in which case the content is expected to be the URL to redirect to.
1189 :param str regex: A regular expression to match the path against.
1190 :param int status: The HTTP code to answer with.
1191 :param str content: The content of the HTTP response, or a URL if the status is a redirection (3xx).
1192 :param table of headers: The custom headers to set for the HTTP response, if any. The default is to use the value of the ``customResponseHeaders`` parameter passed to :func:`addDOHLocal`.
1197 .. class:: TLSContext
1199 .. versionadded:: 1.3.0
1201 This object represents an address and port dnsdist is listening on for DNS over TLS queries.
1203 .. method:: TLSContext:rotateTicketsKey()
1205 Replace the current TLS tickets key by a new random one.
1207 .. method:: TLSContext:loadTicketsKeys(ticketsKeysFile)
1209 Load new tickets keys from the selected file, replacing the existing ones. These keys should be rotated often and never written to persistent storage to preserve forward secrecy. The default is to generate a random key. The OpenSSL provider supports several tickets keys to be able to decrypt existing sessions after the rotation, while the GnuTLS provider only supports one key.
1211 :param str ticketsKeysFile: The path to a file from where TLS tickets keys should be loaded.
1216 .. class:: TLSFrontend
1218 .. versionadded:: 1.3.1
1220 This object represents the configuration of a listening frontend for DNS over TLS queries. To each frontend is associated a TLSContext.
1222 .. method:: TLSContext:loadNewCertificatesAndKeys(certFile(s), keyFile(s))
1224 Create and switch to a new TLS context using the same options than were passed to the corresponding `addTLSLocal()` directive, but loading new certificates and keys from the selected files, replacing the existing ones.
1226 :param str certFile(s): The path to a X.509 certificate file in PEM format, or a list of paths to such files.
1227 :param str keyFile(s): The path to the private key file corresponding to the certificate, or a list of paths to such files, whose order should match the certFile(s) ones.
1229 EDNS on Self-generated answers
1230 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1232 There are several mechanisms in dnsdist that turn an existing query into an answer right away,
1233 without reaching out to the backend, including :func:`SpoofAction`, :func:`RCodeAction`, :func:`TCAction`
1234 and returning a response from ``Lua``. Those responses should, according to :rfc:`6891`, contain an ``OPT``
1235 record if the received request had one, which is the case by default and can be disabled using
1236 :func:`setAddEDNSToSelfGeneratedResponses`.
1238 We must, however, provide a responder's maximum payload size in this record, and we can't easily know the
1239 maximum payload size of the actual backend so we need to provide one. The default value is 1500 and can be
1240 overriden using :func:`setPayloadSizeOnSelfGeneratedAnswers`.
1242 .. function:: setAddEDNSToSelfGeneratedResponses(add)
1244 .. versionadded:: 1.3.3
1246 Whether to add EDNS to self-generated responses, provided that the initial query had EDNS.
1248 :param bool add: Whether to add EDNS, default is true.
1250 .. function:: setPayloadSizeOnSelfGeneratedAnswers(payloadSize)
1252 .. versionadded:: 1.3.3
1254 Set the UDP payload size advertised via EDNS on self-generated responses. In accordance with
1255 :rfc:`RFC 6891 <6891#section-6.2.5>`, values lower than 512 will be treated as equal to 512.
1257 :param int payloadSize: The responder's maximum UDP payload size, in bytes. Default is 1500.
1262 PowerDNS products can poll the security status of their respective versions. This polling, naturally,
1263 happens over DNS. If the result is that a given version has a security problem, the software will
1264 report this at level ‘Error’ during startup, and repeatedly during operations, every
1265 :func:`setSecurityPollInterval` seconds.
1267 By default, security polling happens on the domain ‘secpoll.powerdns.com’, but this can be changed with
1268 the :func:`setSecurityPollSuffix` function. If this setting is made empty, no polling will take place.
1269 Organizations wanting to host their own security zones can do so by changing this setting to a domain name
1270 under their control.
1272 To enable distributors of PowerDNS to signal that they have backported versions, the PACKAGEVERSION
1273 compilation-time macro can be used to set a distributor suffix.
1275 .. function:: setSecurityPollInterval(interval)
1277 .. versionadded:: 1.3.3
1279 Set the interval, in seconds, between two security pollings.
1281 :param int interval: The interval, in seconds, between two pollings. Default is 3600.
1283 .. function:: setSecurityPollSuffix(suffix)
1285 .. versionadded:: 1.3.3
1287 Domain name from which to query security update notifications. Setting this to an empty string disables secpoll.
1289 :param string suffix: The suffix to use, default is 'secpoll.powerdns.com.'.