1 // Copyright (c) The Tor Project, Inc.
2 // See LICENSE for licensing information
3 // This is an asciidoc file used to generate the manpage/html reference.
4 // Learn asciidoc on http://www.methods.co.nz/asciidoc/userguide.html
6 :man manual: Tor Manual
12 tor - The second-generation onion router
17 **tor** [__OPTION__ __value__]...
21 Tor is a connection-oriented anonymizing communication
22 service. Users choose a source-routed path through a set of nodes, and
23 negotiate a "virtual circuit" through the network, in which each node
24 knows its predecessor and successor, but no others. Traffic flowing down
25 the circuit is unwrapped by a symmetric key at each node, which reveals
26 the downstream node. +
28 Basically, Tor provides a distributed network of servers or relays ("onion routers").
29 Users bounce their TCP streams -- web traffic, ftp, ssh, etc. -- around the
30 network, and recipients, observers, and even the relays themselves have
31 difficulty tracking the source of the stream.
33 By default, **tor** will act as a client only. To help the network
34 by providing bandwidth as a relay, change the **ORPort** configuration
35 option -- see below. Please also consult the documentation on the Tor
40 [[opt-h]] **-h**, **-help**::
41 Display a short help message and exit.
43 [[opt-f]] **-f** __FILE__::
44 Specify a new configuration file to contain further Tor configuration
45 options OR pass *-* to make Tor read its configuration from standard
46 input. (Default: @CONFDIR@/torrc, or $HOME/.torrc if that file is not
49 [[opt-allow-missing-torrc]] **--allow-missing-torrc**::
50 Do not require that configuration file specified by **-f** exist if
51 default torrc can be accessed.
53 [[opt-defaults-torrc]] **--defaults-torrc** __FILE__::
54 Specify a file in which to find default values for Tor options. The
55 contents of this file are overridden by those in the regular
56 configuration file, and by those on the command line. (Default:
57 @CONFDIR@/torrc-defaults.)
59 [[opt-ignore-missing-torrc]] **--ignore-missing-torrc**::
60 Specifies that Tor should treat a missing torrc file as though it
61 were empty. Ordinarily, Tor does this for missing default torrc files,
62 but not for those specified on the command line.
64 [[opt-hash-password]] **--hash-password** __PASSWORD__::
65 Generates a hashed password for control port access.
67 [[opt-list-fingerprint]] **--list-fingerprint**::
68 Generate your keys and output your nickname and fingerprint.
70 [[opt-verify-config]] **--verify-config**::
71 Verify the configuration file is valid.
73 [[opt-serviceinstall]] **--service install** [**--options** __command-line options__]::
74 Install an instance of Tor as a Windows service, with the provided
75 command-line options. Current instructions can be found at
76 https://www.torproject.org/docs/faq#NTService
78 [[opt-service]] **--service** **remove**|**start**|**stop**::
79 Remove, start, or stop a configured Tor Windows service.
81 [[opt-nt-service]] **--nt-service**::
82 Used internally to implement a Windows service.
84 [[opt-list-torrc-options]] **--list-torrc-options**::
85 List all valid options.
87 [[opt-list-deprecated-options]] **--list-deprecated-options**::
88 List all valid options that are scheduled to become obsolete in a
89 future version. (This is a warning, not a promise.)
91 [[opt-list-modules]] **--list-modules**::
92 For each optional module, list whether or not it has been compiled
93 into Tor. (Any module not listed is not optional in this version of Tor.)
95 [[opt-version]] **--version**::
96 Display Tor version and exit.
98 [[opt-quiet]] **--quiet**|**--hush**::
99 Override the default console log. By default, Tor starts out logging
100 messages at level "notice" and higher to the console. It stops doing so
101 after it parses its configuration, if the configuration tells it to log
102 anywhere else. You can override this behavior with the **--hush** option,
103 which tells Tor to only send warnings and errors to the console, or with
104 the **--quiet** option, which tells Tor not to log to the console at all.
106 [[opt-keygen]] **--keygen** [**--newpass**]::
107 Running "tor --keygen" creates a new ed25519 master identity key for a
108 relay, or only a fresh temporary signing key and certificate, if you
109 already have a master key. Optionally you can encrypt the master identity
110 key with a passphrase: Tor will ask you for one. If you don't want to
111 encrypt the master key, just don't enter any passphrase when asked. +
113 The **--newpass** option should be used with --keygen only when you need
114 to add, change, or remove a passphrase on an existing ed25519 master
115 identity key. You will be prompted for the old passphase (if any),
116 and the new passphrase (if any). +
118 When generating a master key, you will probably want to use
119 **--DataDirectory** to control where the keys
120 and certificates will be stored, and **--SigningKeyLifetime** to
121 control their lifetimes. Their behavior is as documented in the
122 server options section below. (You must have write access to the specified
125 To use the generated files, you must copy them to the DataDirectory/keys
126 directory of your Tor daemon, and make sure that they are owned by the
127 user actually running the Tor daemon on your system.
129 **--passphrase-fd** __FILEDES__::
130 Filedescriptor to read the passphrase from. Note that unlike with the
131 tor-gencert program, the entire file contents are read and used as
132 the passphrase, including any trailing newlines.
133 Default: read from the terminal.
135 [[opt-key-expiration]] **--key-expiration** [**purpose**]::
136 The **purpose** specifies which type of key certificate to determine
137 the expiration of. The only currently recognised **purpose** is
140 Running "tor --key-expiration sign" will attempt to find your signing
141 key certificate and will output, both in the logs as well as to stdout,
142 the signing key certificate's expiration time in ISO-8601 format.
143 For example, the output sent to stdout will be of the form:
144 "signing-cert-expiry: 2017-07-25 08:30:15 UTC"
146 Other options can be specified on the command-line in the format "--option
147 value", in the format "option value", or in a configuration file. For
148 instance, you can tell Tor to start listening for SOCKS connections on port
149 9999 by passing --SocksPort 9999 or SocksPort 9999 to it on the command line,
150 or by putting "SocksPort 9999" in the configuration file. You will need to
151 quote options with spaces in them: if you want Tor to log all debugging
152 messages to debug.log, you will probably need to say --Log 'debug file
155 Options on the command line override those in configuration files. See the
156 next section for more information.
158 THE CONFIGURATION FILE FORMAT
159 -----------------------------
161 All configuration options in a configuration are written on a single line by
162 default. They take the form of an option name and a value, or an option name
163 and a quoted value (option value or option "value"). Anything after a #
164 character is treated as a comment. Options are
165 case-insensitive. C-style escaped characters are allowed inside quoted
166 values. To split one configuration entry into multiple lines, use a single
167 backslash character (\) before the end of the line. Comments can be used in
168 such multiline entries, but they must start at the beginning of a line.
170 Configuration options can be imported from files or folders using the %include
171 option with the value being a path. If the path is a file, the options from the
172 file will be parsed as if they were written where the %include option is. If
173 the path is a folder, all files on that folder will be parsed following lexical
174 order. Files starting with a dot are ignored. Files on subfolders are ignored.
175 The %include option can be used recursively.
177 By default, an option on the command line overrides an option found in the
178 configuration file, and an option in a configuration file overrides one in
181 This rule is simple for options that take a single value, but it can become
182 complicated for options that are allowed to occur more than once: if you
183 specify four SocksPorts in your configuration file, and one more SocksPort on
184 the command line, the option on the command line will replace __all__ of the
185 SocksPorts in the configuration file. If this isn't what you want, prefix
186 the option name with a plus sign (+), and it will be appended to the previous
187 set of options instead. For example, setting SocksPort 9100 will use only
188 port 9100, but setting +SocksPort 9100 will use ports 9100 and 9050 (because
189 this is the default).
191 Alternatively, you might want to remove every instance of an option in the
192 configuration file, and not replace it at all: you might want to say on the
193 command line that you want no SocksPorts at all. To do that, prefix the
194 option name with a forward slash (/). You can use the plus sign (+) and the
195 forward slash (/) in the configuration file and on the command line.
200 [[BandwidthRate]] **BandwidthRate** __N__ **bytes**|**KBytes**|**MBytes**|**GBytes**|**TBytes**|**KBits**|**MBits**|**GBits**|**TBits**::
201 A token bucket limits the average incoming bandwidth usage on this node
202 to the specified number of bytes per second, and the average outgoing
203 bandwidth usage to that same value. If you want to run a relay in the
204 public network, this needs to be _at the very least_ 75 KBytes for a
205 relay (that is, 600 kbits) or 50 KBytes for a bridge (400 kbits) -- but of
206 course, more is better; we recommend at least 250 KBytes (2 mbits) if
207 possible. (Default: 1 GByte) +
209 Note that this option, and other bandwidth-limiting options, apply to TCP
210 data only: They do not count TCP headers or DNS traffic. +
212 With this option, and in other options that take arguments in bytes,
213 KBytes, and so on, other formats are also supported. Notably, "KBytes" can
214 also be written as "kilobytes" or "kb"; "MBytes" can be written as
215 "megabytes" or "MB"; "kbits" can be written as "kilobits"; and so forth.
216 Tor also accepts "byte" and "bit" in the singular.
217 The prefixes "tera" and "T" are also recognized.
218 If no units are given, we default to bytes.
219 To avoid confusion, we recommend writing "bytes" or "bits" explicitly,
220 since it's easy to forget that "B" means bytes, not bits.
222 [[BandwidthBurst]] **BandwidthBurst** __N__ **bytes**|**KBytes**|**MBytes**|**GBytes**|**TBytes**|**KBits**|**MBits**|**GBits**|**TBits**::
223 Limit the maximum token bucket size (also known as the burst) to the given
224 number of bytes in each direction. (Default: 1 GByte)
226 [[MaxAdvertisedBandwidth]] **MaxAdvertisedBandwidth** __N__ **bytes**|**KBytes**|**MBytes**|**GBytes**|**TBytes**|**KBits**|**MBits**|**GBits**|**TBits**::
227 If set, we will not advertise more than this amount of bandwidth for our
228 BandwidthRate. Server operators who want to reduce the number of clients
229 who ask to build circuits through them (since this is proportional to
230 advertised bandwidth rate) can thus reduce the CPU demands on their server
231 without impacting network performance.
233 [[RelayBandwidthRate]] **RelayBandwidthRate** __N__ **bytes**|**KBytes**|**MBytes**|**GBytes**|**TBytes**|**KBits**|**MBits**|**GBits**|**TBits**::
234 If not 0, a separate token bucket limits the average incoming bandwidth
235 usage for \_relayed traffic_ on this node to the specified number of bytes
236 per second, and the average outgoing bandwidth usage to that same value.
237 Relayed traffic currently is calculated to include answers to directory
238 requests, but that may change in future versions. They do not include directory
239 fetches by the relay (from authority or other relays), because that is considered
240 "client" activity. (Default: 0)
242 [[RelayBandwidthBurst]] **RelayBandwidthBurst** __N__ **bytes**|**KBytes**|**MBytes**|**GBytes**|**TBytes**|**KBits**|**MBits**|**GBits**|**TBits**::
243 If not 0, limit the maximum token bucket size (also known as the burst) for
244 \_relayed traffic_ to the given number of bytes in each direction.
245 They do not include directory fetches by the relay (from authority
246 or other relays), because that is considered "client" activity. (Default: 0)
248 [[PerConnBWRate]] **PerConnBWRate** __N__ **bytes**|**KBytes**|**MBytes**|**GBytes**|**TBytes**|**KBits**|**MBits**|**GBits**|**TBits**::
249 If this option is set manually, or via the "perconnbwrate" consensus
250 field, Tor will use it for separate rate limiting for each connection
251 from a non-relay. (Default: 0)
253 [[PerConnBWBurst]] **PerConnBWBurst** __N__ **bytes**|**KBytes**|**MBytes**|**GBytes**|**TBytes**|**KBits**|**MBits**|**GBits**|**TBits**::
254 If this option is set manually, or via the "perconnbwburst" consensus
255 field, Tor will use it for separate rate limiting for each connection
256 from a non-relay. (Default: 0)
258 [[ClientTransportPlugin]] **ClientTransportPlugin** __transport__ socks4|socks5 __IP__:__PORT__::
259 **ClientTransportPlugin** __transport__ exec __path-to-binary__ [options]::
260 In its first form, when set along with a corresponding Bridge line, the Tor
261 client forwards its traffic to a SOCKS-speaking proxy on "IP:PORT".
262 (IPv4 addresses should written as-is; IPv6 addresses should be wrapped in
263 square brackets.) It's the
264 duty of that proxy to properly forward the traffic to the bridge. +
266 In its second form, when set along with a corresponding Bridge line, the Tor
267 client launches the pluggable transport proxy executable in
268 __path-to-binary__ using __options__ as its command-line options, and
269 forwards its traffic to it. It's the duty of that proxy to properly forward
270 the traffic to the bridge.
272 [[ServerTransportPlugin]] **ServerTransportPlugin** __transport__ exec __path-to-binary__ [options]::
273 The Tor relay launches the pluggable transport proxy in __path-to-binary__
274 using __options__ as its command-line options, and expects to receive
275 proxied client traffic from it.
277 [[ServerTransportListenAddr]] **ServerTransportListenAddr** __transport__ __IP__:__PORT__::
278 When this option is set, Tor will suggest __IP__:__PORT__ as the
279 listening address of any pluggable transport proxy that tries to
280 launch __transport__. (IPv4 addresses should written as-is; IPv6
281 addresses should be wrapped in square brackets.)
283 [[ServerTransportOptions]] **ServerTransportOptions** __transport__ __k=v__ __k=v__ ...::
284 When this option is set, Tor will pass the __k=v__ parameters to
285 any pluggable transport proxy that tries to launch __transport__. +
286 (Example: ServerTransportOptions obfs45 shared-secret=bridgepasswd cache=/var/lib/tor/cache)
288 [[ExtORPort]] **ExtORPort** \['address':]__port__|**auto**::
289 Open this port to listen for Extended ORPort connections from your
290 pluggable transports.
292 [[ExtORPortCookieAuthFile]] **ExtORPortCookieAuthFile** __Path__::
293 If set, this option overrides the default location and file name
294 for the Extended ORPort's cookie file -- the cookie file is needed
295 for pluggable transports to communicate through the Extended ORPort.
297 [[ExtORPortCookieAuthFileGroupReadable]] **ExtORPortCookieAuthFileGroupReadable** **0**|**1**::
298 If this option is set to 0, don't allow the filesystem group to read the
299 Extended OR Port cookie file. If the option is set to 1, make the cookie
300 file readable by the default GID. [Making the file readable by other
301 groups is not yet implemented; let us know if you need this for some
302 reason.] (Default: 0)
304 [[ConnLimit]] **ConnLimit** __NUM__::
305 The minimum number of file descriptors that must be available to the Tor
306 process before it will start. Tor will ask the OS for as many file
307 descriptors as the OS will allow (you can find this by "ulimit -H -n").
308 If this number is less than ConnLimit, then Tor will refuse to start. +
310 Tor relays need thousands of sockets, to connect to every other relay.
311 If you are running a private bridge, you can reduce the number of sockets
312 that Tor uses. For example, to limit Tor to 500 sockets, run
313 "ulimit -n 500" in a shell. Then start tor in the same shell, with
314 **ConnLimit 500**. You may also need to set **DisableOOSCheck 0**. +
316 Unless you have severely limited sockets, you probably don't need to
317 adjust **ConnLimit** itself. It has no effect on Windows, since that
318 platform lacks getrlimit(). (Default: 1000)
320 [[DisableNetwork]] **DisableNetwork** **0**|**1**::
321 When this option is set, we don't listen for or accept any connections
322 other than controller connections, and we close (and don't reattempt)
324 connections. Controllers sometimes use this option to avoid using
325 the network until Tor is fully configured. Tor will make still certain
326 network-related calls (like DNS lookups) as a part of its configuration
327 process, even if DisableNetwork is set. (Default: 0)
329 [[ConstrainedSockets]] **ConstrainedSockets** **0**|**1**::
330 If set, Tor will tell the kernel to attempt to shrink the buffers for all
331 sockets to the size specified in **ConstrainedSockSize**. This is useful for
332 virtual servers and other environments where system level TCP buffers may
333 be limited. If you're on a virtual server, and you encounter the "Error
334 creating network socket: No buffer space available" message, you are
335 likely experiencing this problem. +
337 The preferred solution is to have the admin increase the buffer pool for
338 the host itself via /proc/sys/net/ipv4/tcp_mem or equivalent facility;
339 this configuration option is a second-resort. +
341 The DirPort option should also not be used if TCP buffers are scarce. The
342 cached directory requests consume additional sockets which exacerbates
345 You should **not** enable this feature unless you encounter the "no buffer
346 space available" issue. Reducing the TCP buffers affects window size for
347 the TCP stream and will reduce throughput in proportion to round trip
348 time on long paths. (Default: 0)
350 [[ConstrainedSockSize]] **ConstrainedSockSize** __N__ **bytes**|**KBytes**::
351 When **ConstrainedSockets** is enabled the receive and transmit buffers for
352 all sockets will be set to this limit. Must be a value between 2048 and
353 262144, in 1024 byte increments. Default of 8192 is recommended.
355 [[ControlPort]] **ControlPort** __PORT__|**unix:**__path__|**auto** [__flags__]::
356 If set, Tor will accept connections on this port and allow those
357 connections to control the Tor process using the Tor Control Protocol
358 (described in control-spec.txt in
359 https://spec.torproject.org[torspec]). Note: unless you also
360 specify one or more of **HashedControlPassword** or
361 **CookieAuthentication**, setting this option will cause Tor to allow
362 any process on the local host to control it. (Setting both authentication
363 methods means either method is sufficient to authenticate to Tor.) This
364 option is required for many Tor controllers; most use the value of 9051.
365 If a unix domain socket is used, you may quote the path using standard
367 Set it to "auto" to have Tor pick a port for you. (Default: 0) +
369 Recognized flags are...
371 Unix domain sockets only: makes the socket get created as
374 Unix domain sockets only: makes the socket get created as
376 **RelaxDirModeCheck**;;
377 Unix domain sockets only: Do not insist that the directory
378 that holds the socket be read-restricted.
380 [[ControlSocket]] **ControlSocket** __Path__::
381 Like ControlPort, but listens on a Unix domain socket, rather than a TCP
382 socket. '0' disables ControlSocket. (Unix and Unix-like systems only.)
385 [[ControlSocketsGroupWritable]] **ControlSocketsGroupWritable** **0**|**1**::
386 If this option is set to 0, don't allow the filesystem group to read and
387 write unix sockets (e.g. ControlSocket). If the option is set to 1, make
388 the control socket readable and writable by the default GID. (Default: 0)
390 [[HashedControlPassword]] **HashedControlPassword** __hashed_password__::
391 Allow connections on the control port if they present
392 the password whose one-way hash is __hashed_password__. You
393 can compute the hash of a password by running "tor --hash-password
394 __password__". You can provide several acceptable passwords by using more
395 than one HashedControlPassword line.
397 [[CookieAuthentication]] **CookieAuthentication** **0**|**1**::
398 If this option is set to 1, allow connections on the control port
399 when the connecting process knows the contents of a file named
400 "control_auth_cookie", which Tor will create in its data directory. This
401 authentication method should only be used on systems with good filesystem
402 security. (Default: 0)
404 [[CookieAuthFile]] **CookieAuthFile** __Path__::
405 If set, this option overrides the default location and file name
406 for Tor's cookie file. (See CookieAuthentication above.)
408 [[CookieAuthFileGroupReadable]] **CookieAuthFileGroupReadable** **0**|**1**::
409 If this option is set to 0, don't allow the filesystem group to read the
410 cookie file. If the option is set to 1, make the cookie file readable by
411 the default GID. [Making the file readable by other groups is not yet
412 implemented; let us know if you need this for some reason.] (Default: 0)
414 [[ControlPortWriteToFile]] **ControlPortWriteToFile** __Path__::
415 If set, Tor writes the address and port of any control port it opens to
416 this address. Usable by controllers to learn the actual control port
417 when ControlPort is set to "auto".
419 [[ControlPortFileGroupReadable]] **ControlPortFileGroupReadable** **0**|**1**::
420 If this option is set to 0, don't allow the filesystem group to read the
421 control port file. If the option is set to 1, make the control port
422 file readable by the default GID. (Default: 0)
424 [[DataDirectory]] **DataDirectory** __DIR__::
425 Store working data in DIR. Can not be changed while tor is running.
426 (Default: ~/.tor if your home directory is not /; otherwise,
427 @LOCALSTATEDIR@/lib/tor. On Windows, the default is
428 your ApplicationData folder.)
430 [[DataDirectoryGroupReadable]] **DataDirectoryGroupReadable** **0**|**1**::
431 If this option is set to 0, don't allow the filesystem group to read the
432 DataDirectory. If the option is set to 1, make the DataDirectory readable
433 by the default GID. (Default: 0)
435 [[CacheDirectory]] **CacheDirectory** __DIR__::
436 Store cached directory data in DIR. Can not be changed while tor is
438 (Default: uses the value of DataDirectory.)
440 [[CacheDirectoryGroupReadable]] **CacheDirectoryGroupReadable** **0**|**1**|**auto**::
441 If this option is set to 0, don't allow the filesystem group to read the
442 CacheDirectory. If the option is set to 1, make the CacheDirectory readable
443 by the default GID. If the option is "auto", then we use the
444 setting for DataDirectoryGroupReadable when the CacheDirectory is the
445 same as the DataDirectory, and 0 otherwise. (Default: auto)
447 [[FallbackDir]] **FallbackDir** __ipv4address__:__port__ orport=__port__ id=__fingerprint__ [weight=__num__] [ipv6=**[**__ipv6address__**]**:__orport__]::
448 When we're unable to connect to any directory cache for directory info
449 (usually because we don't know about any yet) we try a directory authority.
450 Clients also simultaneously try a FallbackDir, to avoid hangs on client
451 startup if a directory authority is down. Clients retry FallbackDirs more
452 often than directory authorities, to reduce the load on the directory
454 By default, the directory authorities are also FallbackDirs. Specifying a
455 FallbackDir replaces Tor's default hard-coded FallbackDirs (if any).
456 (See the **DirAuthority** entry for an explanation of each flag.)
458 [[UseDefaultFallbackDirs]] **UseDefaultFallbackDirs** **0**|**1**::
459 Use Tor's default hard-coded FallbackDirs (if any). (When a
460 FallbackDir line is present, it replaces the hard-coded FallbackDirs,
461 regardless of the value of UseDefaultFallbackDirs.) (Default: 1)
463 [[DirAuthority]] **DirAuthority** [__nickname__] [**flags**] __ipv4address__:__port__ __fingerprint__::
464 Use a nonstandard authoritative directory server at the provided address
465 and port, with the specified key fingerprint. This option can be repeated
466 many times, for multiple authoritative directory servers. Flags are
467 separated by spaces, and determine what kind of an authority this directory
468 is. By default, an authority is not authoritative for any directory style
469 or version unless an appropriate flag is given.
470 Tor will use this authority as a bridge authoritative directory if the
471 "bridge" flag is set. If a flag "orport=**port**" is given, Tor will use the
472 given port when opening encrypted tunnels to the dirserver. If a flag
473 "weight=**num**" is given, then the directory server is chosen randomly
474 with probability proportional to that weight (default 1.0). If a
475 flag "v3ident=**fp**" is given, the dirserver is a v3 directory authority
476 whose v3 long-term signing key has the fingerprint **fp**. Lastly,
477 if an "ipv6=**[**__ipv6address__**]**:__orport__" flag is present, then
479 authority is listening for IPv6 connections on the indicated IPv6 address
482 Tor will contact the authority at __ipv4address__ to
483 download directory documents. The provided __port__ value is a dirport;
484 clients ignore this in favor of the specified "orport=" value. If an
485 IPv6 ORPort is supplied, Tor will
486 also download directory documents at the IPv6 ORPort. +
488 If no **DirAuthority** line is given, Tor will use the default directory
489 authorities. NOTE: this option is intended for setting up a private Tor
490 network with its own directory authorities. If you use it, you will be
491 distinguishable from other users, because you won't believe the same
494 [[DirAuthorityFallbackRate]] **DirAuthorityFallbackRate** __NUM__::
495 When configured to use both directory authorities and fallback
496 directories, the directory authorities also work as fallbacks. They are
497 chosen with their regular weights, multiplied by this number, which
498 should be 1.0 or less. The default is less than 1, to reduce load on
499 authorities. (Default: 0.1)
501 [[AlternateDirAuthority]] **AlternateDirAuthority** [__nickname__] [**flags**] __ipv4address__:__port__ __fingerprint__ +
503 [[AlternateBridgeAuthority]] **AlternateBridgeAuthority** [__nickname__] [**flags**] __ipv4address__:__port__ __ fingerprint__::
504 These options behave as DirAuthority, but they replace fewer of the
505 default directory authorities. Using
506 AlternateDirAuthority replaces the default Tor directory authorities, but
507 leaves the default bridge authorities in
509 AlternateBridgeAuthority replaces the default bridge authority,
510 but leaves the directory authorities alone.
512 [[DisableAllSwap]] **DisableAllSwap** **0**|**1**::
513 If set to 1, Tor will attempt to lock all current and future memory pages,
514 so that memory cannot be paged out. Windows, OS X and Solaris are currently
515 not supported. We believe that this feature works on modern Gnu/Linux
516 distributions, and that it should work on *BSD systems (untested). This
517 option requires that you start your Tor as root, and you should use the
518 **User** option to properly reduce Tor's privileges.
519 Can not be changed while tor is running. (Default: 0)
521 [[DisableDebuggerAttachment]] **DisableDebuggerAttachment** **0**|**1**::
522 If set to 1, Tor will attempt to prevent basic debugging attachment attempts
523 by other processes. This may also keep Tor from generating core files if
524 it crashes. It has no impact for users who wish to attach if they
525 have CAP_SYS_PTRACE or if they are root. We believe that this feature
526 works on modern Gnu/Linux distributions, and that it may also work on *BSD
527 systems (untested). Some modern Gnu/Linux systems such as Ubuntu have the
528 kernel.yama.ptrace_scope sysctl and by default enable it as an attempt to
529 limit the PTRACE scope for all user processes by default. This feature will
530 attempt to limit the PTRACE scope for Tor specifically - it will not attempt
531 to alter the system wide ptrace scope as it may not even exist. If you wish
532 to attach to Tor with a debugger such as gdb or strace you will want to set
533 this to 0 for the duration of your debugging. Normal users should leave it
534 on. Disabling this option while Tor is running is prohibited. (Default: 1)
536 [[FetchDirInfoEarly]] **FetchDirInfoEarly** **0**|**1**::
537 If set to 1, Tor will always fetch directory information like other
538 directory caches, even if you don't meet the normal criteria for fetching
539 early. Normal users should leave it off. (Default: 0)
541 [[FetchDirInfoExtraEarly]] **FetchDirInfoExtraEarly** **0**|**1**::
542 If set to 1, Tor will fetch directory information before other directory
543 caches. It will attempt to download directory information closer to the
544 start of the consensus period. Normal users should leave it off.
547 [[FetchHidServDescriptors]] **FetchHidServDescriptors** **0**|**1**::
548 If set to 0, Tor will never fetch any hidden service descriptors from the
549 rendezvous directories. This option is only useful if you're using a Tor
550 controller that handles hidden service fetches for you. (Default: 1)
552 [[FetchServerDescriptors]] **FetchServerDescriptors** **0**|**1**::
553 If set to 0, Tor will never fetch any network status summaries or server
554 descriptors from the directory servers. This option is only useful if
555 you're using a Tor controller that handles directory fetches for you.
558 [[FetchUselessDescriptors]] **FetchUselessDescriptors** **0**|**1**::
559 If set to 1, Tor will fetch every consensus flavor, and all server
560 descriptors and authority certificates referenced by those consensuses,
561 except for extra info descriptors. When this option is 1, Tor will also
562 keep fetching descriptors, even when idle.
563 If set to 0, Tor will avoid fetching useless descriptors: flavors that it
564 is not using to build circuits, and authority certificates it does not
565 trust. When Tor hasn't built any application circuits, it will go idle,
566 and stop fetching descriptors. This option is useful if you're using a
567 tor client with an external parser that uses a full consensus.
568 This option fetches all documents except extrainfo descriptors,
569 **DirCache** fetches and serves all documents except extrainfo
570 descriptors, **DownloadExtraInfo*** fetches extrainfo documents, and serves
571 them if **DirCache** is on, and **UseMicrodescriptors** changes the
572 flavour of consensues and descriptors that is fetched and used for
573 building circuits. (Default: 0)
575 [[HTTPProxy]] **HTTPProxy** __host__[:__port__]::
576 Tor will make all its directory requests through this host:port (or host:80
577 if port is not specified), rather than connecting directly to any directory
578 servers. (DEPRECATED: As of 0.3.1.0-alpha you should use HTTPSProxy.)
580 [[HTTPProxyAuthenticator]] **HTTPProxyAuthenticator** __username:password__::
581 If defined, Tor will use this username:password for Basic HTTP proxy
582 authentication, as in RFC 2617. This is currently the only form of HTTP
583 proxy authentication that Tor supports; feel free to submit a patch if you
584 want it to support others. (DEPRECATED: As of 0.3.1.0-alpha you should use
585 HTTPSProxyAuthenticator.)
587 [[HTTPSProxy]] **HTTPSProxy** __host__[:__port__]::
588 Tor will make all its OR (SSL) connections through this host:port (or
589 host:443 if port is not specified), via HTTP CONNECT rather than connecting
590 directly to servers. You may want to set **FascistFirewall** to restrict
591 the set of ports you might try to connect to, if your HTTPS proxy only
592 allows connecting to certain ports.
594 [[HTTPSProxyAuthenticator]] **HTTPSProxyAuthenticator** __username:password__::
595 If defined, Tor will use this username:password for Basic HTTPS proxy
596 authentication, as in RFC 2617. This is currently the only form of HTTPS
597 proxy authentication that Tor supports; feel free to submit a patch if you
598 want it to support others.
600 [[Sandbox]] **Sandbox** **0**|**1**::
601 If set to 1, Tor will run securely through the use of a syscall sandbox.
602 Otherwise the sandbox will be disabled. The option is currently an
603 experimental feature. It only works on Linux-based operating systems,
604 and only when Tor has been built with the libseccomp library. This option
605 can not be changed while tor is running.
607 When the Sandbox is 1, the following options can not be changed when tor
613 ExtORPortCookieAuthFile
615 ServerDNSResolvConfFile
616 Tor must remain in client or server mode (some changes to ClientOnly and
617 ORPort are not allowed).
618 ClientOnionAuthDir and any files in it won't reload on HUP signal.
621 [[Socks4Proxy]] **Socks4Proxy** __host__[:__port__]::
622 Tor will make all OR connections through the SOCKS 4 proxy at host:port
623 (or host:1080 if port is not specified).
625 [[Socks5Proxy]] **Socks5Proxy** __host__[:__port__]::
626 Tor will make all OR connections through the SOCKS 5 proxy at host:port
627 (or host:1080 if port is not specified).
629 [[Socks5ProxyUsername]] **Socks5ProxyUsername** __username__ +
631 [[Socks5ProxyPassword]] **Socks5ProxyPassword** __password__::
632 If defined, authenticate to the SOCKS 5 server using username and password
633 in accordance to RFC 1929. Both username and password must be between 1 and
636 [[UnixSocksGroupWritable]] **UnixSocksGroupWritable** **0**|**1**::
637 If this option is set to 0, don't allow the filesystem group to read and
638 write unix sockets (e.g. SocksPort unix:). If the option is set to 1, make
639 the Unix socket readable and writable by the default GID. (Default: 0)
641 [[KeepalivePeriod]] **KeepalivePeriod** __NUM__::
642 To keep firewalls from expiring connections, send a padding keepalive cell
643 every NUM seconds on open connections that are in use. (Default: 5 minutes)
645 [[Log]] **Log** __minSeverity__[-__maxSeverity__] **stderr**|**stdout**|**syslog**::
646 Send all messages between __minSeverity__ and __maxSeverity__ to the standard
647 output stream, the standard error stream, or to the system log. (The
648 "syslog" value is only supported on Unix.) Recognized severity levels are
649 debug, info, notice, warn, and err. We advise using "notice" in most cases,
650 since anything more verbose may provide sensitive information to an
651 attacker who obtains the logs. If only one severity level is given, all
652 messages of that level or higher will be sent to the listed destination.
654 [[Log2]] **Log** __minSeverity__[-__maxSeverity__] **file** __FILENAME__::
655 As above, but send log messages to the listed filename. The
656 "Log" option may appear more than once in a configuration file.
657 Messages are sent to all the logs that match their severity
660 [[Log3]] **Log** **[**__domain__,...**]**__minSeverity__[-__maxSeverity__] ... **file** __FILENAME__ +
662 [[Log4]] **Log** **[**__domain__,...**]**__minSeverity__[-__maxSeverity__] ... **stderr**|**stdout**|**syslog**::
663 As above, but select messages by range of log severity __and__ by a
664 set of "logging domains". Each logging domain corresponds to an area of
665 functionality inside Tor. You can specify any number of severity ranges
666 for a single log statement, each of them prefixed by a comma-separated
667 list of logging domains. You can prefix a domain with $$~$$ to indicate
668 negation, and use * to indicate "all domains". If you specify a severity
669 range without a list of domains, it matches all domains. +
671 This is an advanced feature which is most useful for debugging one or two
672 of Tor's subsystems at a time. +
674 The currently recognized domains are: general, crypto, net, config, fs,
675 protocol, mm, http, app, control, circ, rend, bug, dir, dirserv, or, edge,
676 acct, hist, handshake, heartbeat, channel, sched, guard, consdiff, and dos.
677 Domain names are case-insensitive. +
679 For example, "`Log [handshake]debug [~net,~mm]info notice stdout`" sends
680 to stdout: all handshake messages of any severity, all info-and-higher
681 messages from domains other than networking and memory management, and all
682 messages of severity notice or higher.
684 [[LogMessageDomains]] **LogMessageDomains** **0**|**1**::
685 If 1, Tor includes message domains with each log message. Every log
686 message currently has at least one domain; most currently have exactly
687 one. This doesn't affect controller log messages. (Default: 0)
689 [[MaxUnparseableDescSizeToLog]] **MaxUnparseableDescSizeToLog** __N__ **bytes**|**KBytes**|**MBytes**|**GBytes**|**TBytes**::
690 Unparseable descriptors (e.g. for votes, consensuses, routers) are logged
691 in separate files by hash, up to the specified size in total. Note that
692 only files logged during the lifetime of this Tor process count toward the
693 total; this is intended to be used to debug problems without opening live
694 servers to resource exhaustion attacks. (Default: 10 MB)
696 [[OutboundBindAddress]] **OutboundBindAddress** __IP__::
697 Make all outbound connections originate from the IP address specified. This
698 is only useful when you have multiple network interfaces, and you want all
699 of Tor's outgoing connections to use a single one. This option may
700 be used twice, once with an IPv4 address and once with an IPv6 address.
701 IPv6 addresses should be wrapped in square brackets.
702 This setting will be ignored for connections to the loopback addresses
703 (127.0.0.0/8 and ::1), and is not used for DNS requests as well.
705 [[OutboundBindAddressOR]] **OutboundBindAddressOR** __IP__::
706 Make all outbound non-exit (relay and other) connections
707 originate from the IP address specified. This option overrides
708 **OutboundBindAddress** for the same IP version. This option may
709 be used twice, once with an IPv4 address and once with an IPv6
710 address. IPv6 addresses should be wrapped in square brackets.
711 This setting will be ignored for connections to the loopback
712 addresses (127.0.0.0/8 and ::1).
714 [[OutboundBindAddressExit]] **OutboundBindAddressExit** __IP__::
715 Make all outbound exit connections originate from the IP address
716 specified. This option overrides **OutboundBindAddress** for the
717 same IP version. This option may be used twice, once with an IPv4
718 address and once with an IPv6 address.
719 IPv6 addresses should be wrapped in square brackets.
720 This setting will be ignored
721 for connections to the loopback addresses (127.0.0.0/8 and ::1).
723 [[PidFile]] **PidFile** __FILE__::
724 On startup, write our PID to FILE. On clean shutdown, remove
725 FILE. Can not be changed while tor is running.
727 [[ProtocolWarnings]] **ProtocolWarnings** **0**|**1**::
728 If 1, Tor will log with severity \'warn' various cases of other parties not
729 following the Tor specification. Otherwise, they are logged with severity
730 \'info'. (Default: 0)
732 [[RunAsDaemon]] **RunAsDaemon** **0**|**1**::
733 If 1, Tor forks and daemonizes to the background. This option has no effect
734 on Windows; instead you should use the --service command-line option.
735 Can not be changed while tor is running.
738 [[LogTimeGranularity]] **LogTimeGranularity** __NUM__::
739 Set the resolution of timestamps in Tor's logs to NUM milliseconds.
740 NUM must be positive and either a divisor or a multiple of 1 second.
741 Note that this option only controls the granularity written by Tor to
742 a file or console log. Tor does not (for example) "batch up" log
743 messages to affect times logged by a controller, times attached to
744 syslog messages, or the mtime fields on log files. (Default: 1 second)
746 [[TruncateLogFile]] **TruncateLogFile** **0**|**1**::
747 If 1, Tor will overwrite logs at startup and in response to a HUP signal,
748 instead of appending to them. (Default: 0)
750 [[SyslogIdentityTag]] **SyslogIdentityTag** __tag__::
751 When logging to syslog, adds a tag to the syslog identity such that
752 log entries are marked with "Tor-__tag__". Can not be changed while tor is
753 running. (Default: none)
755 [[AndroidIdentityTag]] **AndroidIdentityTag** __tag__::
756 When logging to Android's logging subsystem, adds a tag to the log identity
757 such that log entries are marked with "Tor-__tag__". Can not be changed while
758 tor is running. (Default: none)
760 [[SafeLogging]] **SafeLogging** **0**|**1**|**relay**::
761 Tor can scrub potentially sensitive strings from log messages (e.g.
762 addresses) by replacing them with the string [scrubbed]. This way logs can
763 still be useful, but they don't leave behind personally identifying
764 information about what sites a user might have visited. +
766 If this option is set to 0, Tor will not perform any scrubbing, if it is
767 set to 1, all potentially sensitive strings are replaced. If it is set to
768 relay, all log messages generated when acting as a relay are sanitized, but
769 all messages generated when acting as a client are not.
770 Note: Tor may not heed this option when logging at log levels below Notice.
773 [[User]] **User** __Username__::
774 On startup, setuid to this user and setgid to their primary group.
775 Can not be changed while tor is running.
777 [[KeepBindCapabilities]] **KeepBindCapabilities** **0**|**1**|**auto**::
778 On Linux, when we are started as root and we switch our identity using
779 the **User** option, the **KeepBindCapabilities** option tells us whether to
780 try to retain our ability to bind to low ports. If this value is 1, we
781 try to keep the capability; if it is 0 we do not; and if it is **auto**,
782 we keep the capability only if we are configured to listen on a low port.
783 Can not be changed while tor is running.
786 [[HardwareAccel]] **HardwareAccel** **0**|**1**::
787 If non-zero, try to use built-in (static) crypto hardware acceleration when
788 available. Can not be changed while tor is running. (Default: 0)
790 [[AccelName]] **AccelName** __NAME__::
791 When using OpenSSL hardware crypto acceleration attempt to load the dynamic
792 engine of this name. This must be used for any dynamic hardware engine.
793 Names can be verified with the openssl engine command. Can not be changed
794 while tor is running.
796 [[AccelDir]] **AccelDir** __DIR__::
797 Specify this option if using dynamic hardware acceleration and the engine
798 implementation library resides somewhere other than the OpenSSL default.
799 Can not be changed while tor is running.
801 [[AvoidDiskWrites]] **AvoidDiskWrites** **0**|**1**::
802 If non-zero, try to write to disk less frequently than we would otherwise.
803 This is useful when running on flash memory or other media that support
804 only a limited number of writes. (Default: 0)
806 [[CircuitPriorityHalflife]] **CircuitPriorityHalflife** __NUM__::
807 If this value is set, we override the default algorithm for choosing which
808 circuit's cell to deliver or relay next. It is delivered first to the
809 circuit that has the lowest weighted cell count, where cells are weighted
810 exponentially according to this value (in seconds). If the value is -1, it
811 is taken from the consensus if possible else it will fallback to the
812 default value of 30. Minimum: 1, Maximum: 2147483647. This can be defined
813 as a float value. This is an advanced option; you generally shouldn't have
814 to mess with it. (Default: -1)
816 [[CountPrivateBandwidth]] **CountPrivateBandwidth** **0**|**1**::
817 If this option is set, then Tor's rate-limiting applies not only to
818 remote connections, but also to connections to private addresses like
819 127.0.0.1 or 10.0.0.1. This is mostly useful for debugging
820 rate-limiting. (Default: 0)
822 [[ExtendByEd25519ID]] **ExtendByEd25519ID** **0**|**1**|**auto**::
823 If this option is set to 1, we always try to include a relay's Ed25519 ID
824 when telling the proceeding relay in a circuit to extend to it.
825 If this option is set to 0, we never include Ed25519 IDs when extending
826 circuits. If the option is set to "default", we obey a
827 parameter in the consensus document. (Default: auto)
829 [[NoExec]] **NoExec** **0**|**1**::
830 If this option is set to 1, then Tor will never launch another
831 executable, regardless of the settings of ClientTransportPlugin
832 or ServerTransportPlugin. Once this option has been set to 1,
833 it cannot be set back to 0 without restarting Tor. (Default: 0)
835 [[Schedulers]] **Schedulers** **KIST**|**KISTLite**|**Vanilla**::
836 Specify the scheduler type that tor should use. The scheduler is
837 responsible for moving data around within a Tor process. This is an ordered
838 list by priority which means that the first value will be tried first and if
839 unavailable, the second one is tried and so on. It is possible to change
840 these values at runtime. This option mostly effects relays, and most
841 operators should leave it set to its default value.
842 (Default: KIST,KISTLite,Vanilla)
844 The possible scheduler types are:
846 **KIST**: Kernel-Informed Socket Transport. Tor will use TCP information
847 from the kernel to make informed decisions regarding how much data to send
848 and when to send it. KIST also handles traffic in batches (see
849 KISTSchedRunInterval) in order to improve traffic prioritization decisions.
850 As implemented, KIST will only work on Linux kernel version 2.6.39 or
853 **KISTLite**: Same as KIST but without kernel support. Tor will use all
854 the same mechanics as with KIST, including the batching, but its decisions
855 regarding how much data to send will not be as good. KISTLite will work on
856 all kernels and operating systems, and the majority of the benefits of KIST
857 are still realized with KISTLite.
859 **Vanilla**: The scheduler that Tor used before KIST was implemented. It
860 sends as much data as possible, as soon as possible. Vanilla will work on
861 all kernels and operating systems.
863 [[KISTSchedRunInterval]] **KISTSchedRunInterval** __NUM__ **msec**::
864 If KIST or KISTLite is used in the Schedulers option, this controls at which
865 interval the scheduler tick is. If the value is 0 msec, the value is taken
866 from the consensus if possible else it will fallback to the default 10
867 msec. Maximum possible value is 100 msec. (Default: 0 msec)
869 [[KISTSockBufSizeFactor]] **KISTSockBufSizeFactor** __NUM__::
870 If KIST is used in Schedulers, this is a multiplier of the per-socket
871 limit calculation of the KIST algorithm. (Default: 1.0)
876 The following options are useful only for clients (that is, if
877 **SocksPort**, **HTTPTunnelPort**, **TransPort**, **DNSPort**, or
878 **NATDPort** is non-zero):
880 [[Bridge]] **Bridge** [__transport__] __IP__:__ORPort__ [__fingerprint__]::
881 When set along with UseBridges, instructs Tor to use the relay at
882 "IP:ORPort" as a "bridge" relaying into the Tor network. If "fingerprint"
883 is provided (using the same format as for DirAuthority), we will verify that
884 the relay running at that location has the right fingerprint. We also use
885 fingerprint to look up the bridge descriptor at the bridge authority, if
886 it's provided and if UpdateBridgesFromAuthority is set too. +
888 If "transport" is provided, it must match a ClientTransportPlugin line. We
889 then use that pluggable transport's proxy to transfer data to the bridge,
890 rather than connecting to the bridge directly. Some transports use a
891 transport-specific method to work out the remote address to connect to.
892 These transports typically ignore the "IP:ORPort" specified in the bridge
895 Tor passes any "key=val" settings to the pluggable transport proxy as
896 per-connection arguments when connecting to the bridge. Consult
897 the documentation of the pluggable transport for details of what
898 arguments it supports.
900 [[LearnCircuitBuildTimeout]] **LearnCircuitBuildTimeout** **0**|**1**::
901 If 0, CircuitBuildTimeout adaptive learning is disabled. (Default: 1)
903 [[CircuitBuildTimeout]] **CircuitBuildTimeout** __NUM__::
905 Try for at most NUM seconds when building circuits. If the circuit isn't
906 open in that time, give up on it. If LearnCircuitBuildTimeout is 1, this
907 value serves as the initial value to use before a timeout is learned. If
908 LearnCircuitBuildTimeout is 0, this value is the only value used.
909 (Default: 60 seconds)
911 [[CircuitsAvailableTimeout]] **CircuitsAvailableTimeout** __NUM__::
912 Tor will attempt to keep at least one open, unused circuit available for
913 this amount of time. This option governs how long idle circuits are kept
914 open, as well as the amount of time Tor will keep a circuit open to each
915 of the recently used ports. This way when the Tor client is entirely
916 idle, it can expire all of its circuits, and then expire its TLS
917 connections. Note that the actual timeout value is uniformly randomized
918 from the specified value to twice that amount. (Default: 30 minutes;
921 [[CircuitStreamTimeout]] **CircuitStreamTimeout** __NUM__::
922 If non-zero, this option overrides our internal timeout schedule for how
923 many seconds until we detach a stream from a circuit and try a new circuit.
924 If your network is particularly slow, you might want to set this to a
925 number like 60. (Default: 0)
927 [[ClientOnly]] **ClientOnly** **0**|**1**::
928 If set to 1, Tor will not run as a relay or serve
929 directory requests, even if the ORPort, ExtORPort, or DirPort options are
930 set. (This config option is
931 mostly unnecessary: we added it back when we were considering having
932 Tor clients auto-promote themselves to being relays if they were stable
933 and fast enough. The current behavior is simply that Tor is a client
934 unless ORPort, ExtORPort, or DirPort are configured.) (Default: 0)
936 [[ConnectionPadding]] **ConnectionPadding** **0**|**1**|**auto**::
937 This option governs Tor's use of padding to defend against some forms of
938 traffic analysis. If it is set to 'auto', Tor will send padding only
939 if both the client and the relay support it. If it is set to 0, Tor will
940 not send any padding cells. If it is set to 1, Tor will still send padding
941 for client connections regardless of relay support. Only clients may set
942 this option. This option should be offered via the UI to mobile users
943 for use where bandwidth may be expensive.
946 [[ReducedConnectionPadding]] **ReducedConnectionPadding** **0**|**1**::
947 If set to 1, Tor will not not hold OR connections open for very long,
948 and will send less padding on these connections. Only clients may set
949 this option. This option should be offered via the UI to mobile users
950 for use where bandwidth may be expensive. (Default: 0)
952 [[ExcludeNodes]] **ExcludeNodes** __node__,__node__,__...__::
953 A list of identity fingerprints, country codes, and address
954 patterns of nodes to avoid when building a circuit. Country codes are
955 2-letter ISO3166 codes, and must
956 be wrapped in braces; fingerprints may be preceded by a dollar sign.
958 ExcludeNodes ABCD1234CDEF5678ABCD1234CDEF5678ABCD1234, \{cc}, 255.254.0.0/8) +
960 By default, this option is treated as a preference that Tor is allowed
961 to override in order to keep working.
962 For example, if you try to connect to a hidden service,
963 but you have excluded all of the hidden service's introduction points,
964 Tor will connect to one of them anyway. If you do not want this
965 behavior, set the StrictNodes option (documented below). +
967 Note also that if you are a relay, this (and the other node selection
968 options below) only affects your own circuits that Tor builds for you.
969 Clients can still build circuits through you to any node. Controllers
970 can tell Tor to build circuits through any node. +
972 Country codes are case-insensitive. The code "\{??}" refers to nodes whose
973 country can't be identified. No country code, including \{??}, works if
974 no GeoIPFile can be loaded. See also the GeoIPExcludeUnknown option below.
977 [[ExcludeExitNodes]] **ExcludeExitNodes** __node__,__node__,__...__::
978 A list of identity fingerprints, country codes, and address
979 patterns of nodes to never use when picking an exit node---that is, a
980 node that delivers traffic for you *outside* the Tor network. Note that any
981 node listed in ExcludeNodes is automatically considered to be part of this
983 the **ExcludeNodes** option for more information on how to specify
984 nodes. See also the caveats on the "ExitNodes" option below.
986 [[GeoIPExcludeUnknown]] **GeoIPExcludeUnknown** **0**|**1**|**auto**::
987 If this option is set to 'auto', then whenever any country code is set in
988 ExcludeNodes or ExcludeExitNodes, all nodes with unknown country (\{??} and
989 possibly \{A1}) are treated as excluded as well. If this option is set to
990 '1', then all unknown countries are treated as excluded in ExcludeNodes
991 and ExcludeExitNodes. This option has no effect when a GeoIP file isn't
992 configured or can't be found. (Default: auto)
994 [[ExitNodes]] **ExitNodes** __node__,__node__,__...__::
995 A list of identity fingerprints, country codes, and address
996 patterns of nodes to use as exit node---that is, a
997 node that delivers traffic for you *outside* the Tor network. See
998 the **ExcludeNodes** option for more information on how to specify nodes. +
1000 Note that if you list too few nodes here, or if you exclude too many exit
1001 nodes with ExcludeExitNodes, you can degrade functionality. For example,
1002 if none of the exits you list allows traffic on port 80 or 443, you won't
1003 be able to browse the web. +
1005 Note also that not every circuit is used to deliver traffic *outside* of
1006 the Tor network. It is normal to see non-exit circuits (such as those
1007 used to connect to hidden services, those that do directory fetches,
1008 those used for relay reachability self-tests, and so on) that end
1009 at a non-exit node. To
1010 keep a node from being used entirely, see ExcludeNodes and StrictNodes. +
1012 The ExcludeNodes option overrides this option: any node listed in both
1013 ExitNodes and ExcludeNodes is treated as excluded. +
1015 The .exit address notation, if enabled via MapAddress, overrides
1018 [[EntryNodes]] **EntryNodes** __node__,__node__,__...__::
1019 A list of identity fingerprints and country codes of nodes
1020 to use for the first hop in your normal circuits.
1021 Normal circuits include all
1022 circuits except for direct connections to directory servers. The Bridge
1023 option overrides this option; if you have configured bridges and
1024 UseBridges is 1, the Bridges are used as your entry nodes. +
1026 The ExcludeNodes option overrides this option: any node listed in both
1027 EntryNodes and ExcludeNodes is treated as excluded. See
1028 the **ExcludeNodes** option for more information on how to specify nodes.
1030 [[StrictNodes]] **StrictNodes** **0**|**1**::
1031 If StrictNodes is set to 1, Tor will treat solely the ExcludeNodes option
1032 as a requirement to follow for all the circuits you generate, even if
1033 doing so will break functionality for you (StrictNodes applies to neither
1034 ExcludeExitNodes nor to ExitNodes). If StrictNodes is set to 0, Tor will
1035 still try to avoid nodes in the ExcludeNodes list, but it will err on the
1036 side of avoiding unexpected errors. Specifically, StrictNodes 0 tells Tor
1037 that it is okay to use an excluded node when it is *necessary* to perform
1038 relay reachability self-tests, connect to a hidden service, provide a
1039 hidden service to a client, fulfill a .exit request, upload directory
1040 information, or download directory information. (Default: 0)
1042 [[FascistFirewall]] **FascistFirewall** **0**|**1**::
1043 If 1, Tor will only create outgoing connections to ORs running on ports
1044 that your firewall allows (defaults to 80 and 443; see **FirewallPorts**).
1045 This will allow you to run Tor as a client behind a firewall with
1046 restrictive policies, but will not allow you to run as a server behind such
1047 a firewall. If you prefer more fine-grained control, use
1048 ReachableAddresses instead.
1050 [[FirewallPorts]] **FirewallPorts** __PORTS__::
1051 A list of ports that your firewall allows you to connect to. Only used when
1052 **FascistFirewall** is set. This option is deprecated; use ReachableAddresses
1053 instead. (Default: 80, 443)
1055 [[ReachableAddresses]] **ReachableAddresses** __IP__[/__MASK__][:__PORT__]...::
1056 A comma-separated list of IP addresses and ports that your firewall allows
1057 you to connect to. The format is as for the addresses in ExitPolicy, except
1058 that "accept" is understood unless "reject" is explicitly provided. For
1059 example, \'ReachableAddresses 99.0.0.0/8, reject 18.0.0.0/8:80, accept
1060 \*:80' means that your firewall allows connections to everything inside net
1061 99, rejects port 80 connections to net 18, and accepts connections to port
1062 80 otherwise. (Default: \'accept \*:*'.)
1064 [[ReachableDirAddresses]] **ReachableDirAddresses** __IP__[/__MASK__][:__PORT__]...::
1065 Like **ReachableAddresses**, a list of addresses and ports. Tor will obey
1066 these restrictions when fetching directory information, using standard HTTP
1067 GET requests. If not set explicitly then the value of
1068 **ReachableAddresses** is used. If **HTTPProxy** is set then these
1069 connections will go through that proxy. (DEPRECATED: This option has
1070 had no effect for some time.)
1072 [[ReachableORAddresses]] **ReachableORAddresses** __IP__[/__MASK__][:__PORT__]...::
1073 Like **ReachableAddresses**, a list of addresses and ports. Tor will obey
1074 these restrictions when connecting to Onion Routers, using TLS/SSL. If not
1075 set explicitly then the value of **ReachableAddresses** is used. If
1076 **HTTPSProxy** is set then these connections will go through that proxy. +
1078 The separation between **ReachableORAddresses** and
1079 **ReachableDirAddresses** is only interesting when you are connecting
1080 through proxies (see **HTTPProxy** and **HTTPSProxy**). Most proxies limit
1081 TLS connections (which Tor uses to connect to Onion Routers) to port 443,
1082 and some limit HTTP GET requests (which Tor uses for fetching directory
1083 information) to port 80.
1085 [[HidServAuth]] **HidServAuth** __onion-address__ __auth-cookie__ [__service-name__]::
1086 Client authorization for a hidden service. Valid onion addresses contain 16
1087 characters in a-z2-7 plus ".onion", and valid auth cookies contain 22
1088 characters in A-Za-z0-9+/. The service name is only used for internal
1089 purposes, e.g., for Tor controllers. This option may be used multiple times
1090 for different hidden services. If a hidden service uses authorization and
1091 this option is not set, the hidden service is not accessible. Hidden
1092 services can be configured to require authorization using the
1093 **HiddenServiceAuthorizeClient** option.
1095 [[ClientOnionAuthDir]] **ClientOnionAuthDir** __path__::
1096 Path to the directory containing v3 hidden service authorization files.
1097 Each file is for a single onion address, and the files MUST have the suffix
1098 ".auth_private" (i.e. "bob_onion.auth_private"). The content format MUST be:
1100 <onion-address>:descriptor:x25519:<base32-encoded-privkey>
1102 The <onion-address> MUST NOT have the ".onion" suffix. The
1103 <base32-encoded-privkey> is the base32 representation of the raw key bytes
1104 only (32 bytes for x25519). See Appendix G in the rend-spec-v3.txt file of
1105 https://spec.torproject.org/[torspec] for more information.
1107 [[LongLivedPorts]] **LongLivedPorts** __PORTS__::
1108 A list of ports for services that tend to have long-running connections
1109 (e.g. chat and interactive shells). Circuits for streams that use these
1110 ports will contain only high-uptime nodes, to reduce the chance that a node
1111 will go down before the stream is finished. Note that the list is also
1112 honored for circuits (both client and service side) involving hidden
1113 services whose virtual port is in this list. (Default: 21, 22, 706,
1114 1863, 5050, 5190, 5222, 5223, 6523, 6667, 6697, 8300)
1116 [[MapAddress]] **MapAddress** __address__ __newaddress__::
1117 When a request for address arrives to Tor, it will transform to newaddress
1118 before processing it. For example, if you always want connections to
1119 www.example.com to exit via __torserver__ (where __torserver__ is the
1120 fingerprint of the server), use "MapAddress www.example.com
1121 www.example.com.torserver.exit". If the value is prefixed with a
1122 "\*.", matches an entire domain. For example, if you
1123 always want connections to example.com and any if its subdomains
1125 __torserver__ (where __torserver__ is the fingerprint of the server), use
1126 "MapAddress \*.example.com \*.example.com.torserver.exit". (Note the
1127 leading "*." in each part of the directive.) You can also redirect all
1128 subdomains of a domain to a single address. For example, "MapAddress
1129 *.example.com www.example.com". +
1133 1. When evaluating MapAddress expressions Tor stops when it hits the most
1134 recently added expression that matches the requested address. So if you
1135 have the following in your torrc, www.torproject.org will map to 1.1.1.1:
1137 MapAddress www.torproject.org 2.2.2.2
1138 MapAddress www.torproject.org 1.1.1.1
1140 2. Tor evaluates the MapAddress configuration until it finds no matches. So
1141 if you have the following in your torrc, www.torproject.org will map to
1144 MapAddress 1.1.1.1 2.2.2.2
1145 MapAddress www.torproject.org 1.1.1.1
1147 3. The following MapAddress expression is invalid (and will be
1148 ignored) because you cannot map from a specific address to a wildcard
1151 MapAddress www.torproject.org *.torproject.org.torserver.exit
1153 4. Using a wildcard to match only part of a string (as in *ample.com) is
1156 [[NewCircuitPeriod]] **NewCircuitPeriod** __NUM__::
1157 Every NUM seconds consider whether to build a new circuit. (Default: 30
1160 [[MaxCircuitDirtiness]] **MaxCircuitDirtiness** __NUM__::
1161 Feel free to reuse a circuit that was first used at most NUM seconds ago,
1162 but never attach a new stream to a circuit that is too old. For hidden
1163 services, this applies to the __last__ time a circuit was used, not the
1164 first. Circuits with streams constructed with SOCKS authentication via
1165 SocksPorts that have **KeepAliveIsolateSOCKSAuth** also remain alive
1166 for MaxCircuitDirtiness seconds after carrying the last such stream.
1167 (Default: 10 minutes)
1169 [[MaxClientCircuitsPending]] **MaxClientCircuitsPending** __NUM__::
1170 Do not allow more than NUM circuits to be pending at a time for handling
1171 client streams. A circuit is pending if we have begun constructing it,
1172 but it has not yet been completely constructed. (Default: 32)
1174 [[NodeFamily]] **NodeFamily** __node__,__node__,__...__::
1175 The Tor servers, defined by their identity fingerprints,
1176 constitute a "family" of similar or co-administered servers, so never use
1177 any two of them in the same circuit. Defining a NodeFamily is only needed
1178 when a server doesn't list the family itself (with MyFamily). This option
1179 can be used multiple times; each instance defines a separate family. In
1180 addition to nodes, you can also list IP address and ranges and country
1181 codes in {curly braces}. See the **ExcludeNodes** option for more
1182 information on how to specify nodes.
1184 [[EnforceDistinctSubnets]] **EnforceDistinctSubnets** **0**|**1**::
1185 If 1, Tor will not put two servers whose IP addresses are "too close" on
1186 the same circuit. Currently, two addresses are "too close" if they lie in
1187 the same /16 range. (Default: 1)
1189 [[SocksPort]] **SocksPort** \['address':]__port__|**unix:**__path__|**auto** [_flags_] [_isolation flags_]::
1190 Open this port to listen for connections from SOCKS-speaking
1191 applications. Set this to 0 if you don't want to allow application
1192 connections via SOCKS. Set it to "auto" to have Tor pick a port for
1193 you. This directive can be specified multiple times to bind
1194 to multiple addresses/ports. If a unix domain socket is used, you may
1195 quote the path using standard C escape sequences.
1198 NOTE: Although this option allows you to specify an IP address
1199 other than localhost, you should do so only with extreme caution.
1200 The SOCKS protocol is unencrypted and (as we use it)
1201 unauthenticated, so exposing it in this way could leak your
1202 information to anybody watching your network, and allow anybody
1203 to use your computer as an open proxy. +
1205 The _isolation flags_ arguments give Tor rules for which streams
1206 received on this SocksPort are allowed to share circuits with one
1207 another. Recognized isolation flags are:
1208 **IsolateClientAddr**;;
1209 Don't share circuits with streams from a different
1210 client address. (On by default and strongly recommended when
1211 supported; you can disable it with **NoIsolateClientAddr**.
1212 Unsupported and force-disabled when using Unix domain sockets.)
1213 **IsolateSOCKSAuth**;;
1214 Don't share circuits with streams for which different
1215 SOCKS authentication was provided. (For HTTPTunnelPort
1216 connections, this option looks at the Proxy-Authorization and
1217 X-Tor-Stream-Isolation headers. On by default;
1218 you can disable it with **NoIsolateSOCKSAuth**.)
1219 **IsolateClientProtocol**;;
1220 Don't share circuits with streams using a different protocol.
1221 (SOCKS 4, SOCKS 5, TransPort connections, NATDPort connections,
1222 and DNSPort requests are all considered to be different protocols.)
1223 **IsolateDestPort**;;
1224 Don't share circuits with streams targeting a different
1226 **IsolateDestAddr**;;
1227 Don't share circuits with streams targeting a different
1228 destination address.
1229 **KeepAliveIsolateSOCKSAuth**;;
1230 If **IsolateSOCKSAuth** is enabled, keep alive circuits while they have
1231 at least one stream with SOCKS authentication active. After such a circuit
1232 is idle for more than MaxCircuitDirtiness seconds, it can be closed.
1233 **SessionGroup=**__INT__;;
1234 If no other isolation rules would prevent it, allow streams
1235 on this port to share circuits with streams from every other
1236 port with the same session group. (By default, streams received
1237 on different SocksPorts, TransPorts, etc are always isolated from one
1238 another. This option overrides that behavior.)
1240 // Anchor only for formatting, not visible in the man page.
1241 [[OtherSocksPortFlags]]::
1242 Other recognized __flags__ for a SocksPort are:
1244 Tell exits to not connect to IPv4 addresses in response to SOCKS
1245 requests on this connection.
1247 Tell exits to allow IPv6 addresses in response to SOCKS requests on
1248 this connection, so long as SOCKS5 is in use. (SOCKS4 can't handle
1251 Tells exits that, if a host has both an IPv4 and an IPv6 address,
1252 we would prefer to connect to it via IPv6. (IPv4 is the default.)
1254 Do not ask exits to resolve DNS addresses in SOCKS5 requests. Tor will
1255 connect to IPv4 addresses, IPv6 addresses (if IPv6Traffic is set) and
1257 **NoOnionTraffic**;;
1258 Do not connect to .onion addresses in SOCKS5 requests.
1259 **OnionTrafficOnly**;;
1260 Tell the tor client to only connect to .onion addresses in response to
1261 SOCKS5 requests on this connection. This is equivalent to NoDNSRequest,
1262 NoIPv4Traffic, NoIPv6Traffic. The corresponding NoOnionTrafficOnly
1263 flag is not supported.
1265 Tells the client to remember IPv4 DNS answers we receive from exit
1266 nodes via this connection.
1268 Tells the client to remember IPv6 DNS answers we receive from exit
1269 nodes via this connection.
1271 Unix domain sockets only: makes the socket get created as
1274 Unix domain sockets only: makes the socket get created as
1277 Tells the client to remember all DNS answers we receive from exit
1278 nodes via this connection.
1280 Tells the client to use any cached IPv4 DNS answers we have when making
1281 requests via this connection. (NOTE: This option, or UseIPv6Cache
1282 or UseDNSCache, can harm your anonymity, and probably
1283 won't help performance as much as you might expect. Use with care!)
1285 Tells the client to use any cached IPv6 DNS answers we have when making
1286 requests via this connection.
1288 Tells the client to use any cached DNS answers we have when making
1289 requests via this connection.
1290 **PreferIPv6Automap**;;
1291 When serving a hostname lookup request on this port that
1292 should get automapped (according to AutomapHostsOnResolve),
1293 if we could return either an IPv4 or an IPv6 answer, prefer
1294 an IPv6 answer. (On by default.)
1295 **PreferSOCKSNoAuth**;;
1296 Ordinarily, when an application offers both "username/password
1297 authentication" and "no authentication" to Tor via SOCKS5, Tor
1298 selects username/password authentication so that IsolateSOCKSAuth can
1299 work. This can confuse some applications, if they offer a
1300 username/password combination then get confused when asked for
1301 one. You can disable this behavior, so that Tor will select "No
1302 authentication" when IsolateSOCKSAuth is disabled, or when this
1305 // Anchor only for formatting, not visible in the man page.
1306 [[SocksPortFlagsMisc]]::
1307 Flags are processed left to right. If flags conflict, the last flag on the
1308 line is used, and all earlier flags are ignored. No error is issued for
1311 [[SocksPolicy]] **SocksPolicy** __policy__,__policy__,__...__::
1312 Set an entrance policy for this server, to limit who can connect to the
1313 SocksPort and DNSPort ports. The policies have the same form as exit
1314 policies below, except that port specifiers are ignored. Any address
1315 not matched by some entry in the policy is accepted.
1317 [[SocksTimeout]] **SocksTimeout** __NUM__::
1318 Let a socks connection wait NUM seconds handshaking, and NUM seconds
1319 unattached waiting for an appropriate circuit, before we fail it. (Default:
1322 [[TokenBucketRefillInterval]] **TokenBucketRefillInterval** __NUM__ [**msec**|**second**]::
1323 Set the refill delay interval of Tor's token bucket to NUM milliseconds.
1324 NUM must be between 1 and 1000, inclusive. When Tor is out of bandwidth,
1325 on a connection or globally, it will wait up to this long before it tries
1326 to use that connection again.
1327 Note that bandwidth limits are still expressed in bytes per second: this
1328 option only affects the frequency with which Tor checks to see whether
1329 previously exhausted connections may read again.
1330 Can not be changed while tor is running. (Default: 100 msec)
1332 [[TrackHostExits]] **TrackHostExits** __host__,__.domain__,__...__::
1333 For each value in the comma separated list, Tor will track recent
1334 connections to hosts that match this value and attempt to reuse the same
1335 exit node for each. If the value is prepended with a \'.\', it is treated as
1336 matching an entire domain. If one of the values is just a \'.', it means
1337 match everything. This option is useful if you frequently connect to sites
1338 that will expire all your authentication cookies (i.e. log you out) if
1339 your IP address changes. Note that this option does have the disadvantage
1340 of making it more clear that a given history is associated with a single
1341 user. However, most people who would wish to observe this will observe it
1342 through cookies or other protocol-specific means anyhow.
1344 [[TrackHostExitsExpire]] **TrackHostExitsExpire** __NUM__::
1345 Since exit servers go up and down, it is desirable to expire the
1346 association between host and exit server after NUM seconds. The default is
1347 1800 seconds (30 minutes).
1349 [[UpdateBridgesFromAuthority]] **UpdateBridgesFromAuthority** **0**|**1**::
1350 When set (along with UseBridges), Tor will try to fetch bridge descriptors
1351 from the configured bridge authorities when feasible. It will fall back to
1352 a direct request if the authority responds with a 404. (Default: 0)
1354 [[UseBridges]] **UseBridges** **0**|**1**::
1355 When set, Tor will fetch descriptors for each bridge listed in the "Bridge"
1356 config lines, and use these relays as both entry guards and directory
1357 guards. (Default: 0)
1359 [[UseEntryGuards]] **UseEntryGuards** **0**|**1**::
1360 If this option is set to 1, we pick a few long-term entry servers, and try
1361 to stick with them. This is desirable because constantly changing servers
1362 increases the odds that an adversary who owns some servers will observe a
1363 fraction of your paths. Entry Guards can not be used by Directory
1364 Authorities or Single Onion Services. In these cases,
1365 this option is ignored. (Default: 1)
1367 [[GuardfractionFile]] **GuardfractionFile** __FILENAME__::
1368 V3 authoritative directories only. Configures the location of the
1369 guardfraction file which contains information about how long relays
1370 have been guards. (Default: unset)
1372 [[UseGuardFraction]] **UseGuardFraction** **0**|**1**|**auto**::
1373 This option specifies whether clients should use the
1374 guardfraction information found in the consensus during path
1375 selection. If it's set to 'auto', clients will do what the
1376 UseGuardFraction consensus parameter tells them to do. (Default: auto)
1378 [[NumEntryGuards]] **NumEntryGuards** __NUM__::
1379 If UseEntryGuards is set to 1, we will try to pick a total of NUM routers
1380 as long-term entries for our circuits. If NUM is 0, we try to learn the
1381 number from the guard-n-primary-guards-to-use consensus parameter, and
1382 default to 1 if the consensus parameter isn't set. (Default: 0)
1384 [[NumPrimaryGuards]] **NumPrimaryGuards** __NUM__::
1385 If UseEntryGuards is set to 1, we will try to pick NUM routers for our
1386 primary guard list, which is the set of routers we strongly prefer when
1387 connecting to the Tor network. If NUM is 0, we try to learn the number from
1388 the guard-n-primary-guards consensus parameter, and default to 3 if the
1389 consensus parameter isn't set. (Default: 0)
1391 [[NumDirectoryGuards]] **NumDirectoryGuards** __NUM__::
1392 If UseEntryGuards is set to 1, we try to make sure we have at least NUM
1393 routers to use as directory guards. If this option is set to 0, use the
1394 value from the guard-n-primary-dir-guards-to-use consensus parameter, and
1395 default to 3 if the consensus parameter isn't set. (Default: 0)
1397 [[GuardLifetime]] **GuardLifetime** __N__ **days**|**weeks**|**months**::
1398 If nonzero, and UseEntryGuards is set, minimum time to keep a guard before
1399 picking a new one. If zero, we use the GuardLifetime parameter from the
1400 consensus directory. No value here may be less than 1 month or greater
1401 than 5 years; out-of-range values are clamped. (Default: 0)
1403 [[SafeSocks]] **SafeSocks** **0**|**1**::
1404 When this option is enabled, Tor will reject application connections that
1405 use unsafe variants of the socks protocol -- ones that only provide an IP
1406 address, meaning the application is doing a DNS resolve first.
1407 Specifically, these are socks4 and socks5 when not doing remote DNS.
1410 [[TestSocks]] **TestSocks** **0**|**1**::
1411 When this option is enabled, Tor will make a notice-level log entry for
1412 each connection to the Socks port indicating whether the request used a
1413 safe socks protocol or an unsafe one (see above entry on SafeSocks). This
1414 helps to determine whether an application using Tor is possibly leaking
1415 DNS requests. (Default: 0)
1417 [[VirtualAddrNetworkIPv4]] **VirtualAddrNetworkIPv4** __IPv4Address__/__bits__ +
1419 [[VirtualAddrNetworkIPv6]] **VirtualAddrNetworkIPv6** [__IPv6Address__]/__bits__::
1420 When Tor needs to assign a virtual (unused) address because of a MAPADDRESS
1421 command from the controller or the AutomapHostsOnResolve feature, Tor
1422 picks an unassigned address from this range. (Defaults:
1423 127.192.0.0/10 and [FE80::]/10 respectively.) +
1425 When providing proxy server service to a network of computers using a tool
1426 like dns-proxy-tor, change the IPv4 network to "10.192.0.0/10" or
1427 "172.16.0.0/12" and change the IPv6 network to "[FC00::]/7".
1428 The default **VirtualAddrNetwork** address ranges on a
1429 properly configured machine will route to the loopback or link-local
1430 interface. The maximum number of bits for the network prefix is set to 104
1431 for IPv6 and 16 for IPv4. However, a wider network - smaller prefix length
1432 - is preferable since it reduces the chances for an attacker to guess the
1433 used IP. For local use, no change to the default VirtualAddrNetwork setting
1436 [[AllowNonRFC953Hostnames]] **AllowNonRFC953Hostnames** **0**|**1**::
1437 When this option is disabled, Tor blocks hostnames containing illegal
1438 characters (like @ and :) rather than sending them to an exit node to be
1439 resolved. This helps trap accidental attempts to resolve URLs and so on.
1442 [[HTTPTunnelPort]] **HTTPTunnelPort** \['address':]__port__|**auto** [_isolation flags_]::
1443 Open this port to listen for proxy connections using the "HTTP CONNECT"
1444 protocol instead of SOCKS. Set this to
1445 0 if you don't want to allow "HTTP CONNECT" connections. Set the port
1446 to "auto" to have Tor pick a port for you. This directive can be
1447 specified multiple times to bind to multiple addresses/ports. See
1448 SOCKSPort for an explanation of isolation flags. (Default: 0)
1450 [[TransPort]] **TransPort** \['address':]__port__|**auto** [_isolation flags_]::
1451 Open this port to listen for transparent proxy connections. Set this to
1452 0 if you don't want to allow transparent proxy connections. Set the port
1453 to "auto" to have Tor pick a port for you. This directive can be
1454 specified multiple times to bind to multiple addresses/ports. See
1455 SOCKSPort for an explanation of isolation flags. +
1457 TransPort requires OS support for transparent proxies, such as BSDs' pf or
1458 Linux's IPTables. If you're planning to use Tor as a transparent proxy for
1459 a network, you'll want to examine and change VirtualAddrNetwork from the
1460 default setting. (Default: 0)
1462 [[TransProxyType]] **TransProxyType** **default**|**TPROXY**|**ipfw**|**pf-divert**::
1463 TransProxyType may only be enabled when there is transparent proxy listener
1466 Set this to "TPROXY" if you wish to be able to use the TPROXY Linux module
1467 to transparently proxy connections that are configured using the TransPort
1468 option. Detailed information on how to configure the TPROXY
1469 feature can be found in the Linux kernel source tree in the file
1470 Documentation/networking/tproxy.txt. +
1472 Set this option to "ipfw" to use the FreeBSD ipfw interface. +
1474 On *BSD operating systems when using pf, set this to "pf-divert" to take
1475 advantage of +divert-to+ rules, which do not modify the packets like
1476 +rdr-to+ rules do. Detailed information on how to configure pf to use
1477 +divert-to+ rules can be found in the pf.conf(5) manual page. On OpenBSD,
1478 +divert-to+ is available to use on versions greater than or equal to
1481 Set this to "default", or leave it unconfigured, to use regular IPTables
1482 on Linux, or to use pf +rdr-to+ rules on *BSD systems. +
1484 (Default: "default")
1486 [[NATDPort]] **NATDPort** \['address':]__port__|**auto** [_isolation flags_]::
1487 Open this port to listen for connections from old versions of ipfw (as
1488 included in old versions of FreeBSD, etc) using the NATD protocol.
1489 Use 0 if you don't want to allow NATD connections. Set the port
1490 to "auto" to have Tor pick a port for you. This directive can be
1491 specified multiple times to bind to multiple addresses/ports. See
1492 SocksPort for an explanation of isolation flags. +
1494 This option is only for people who cannot use TransPort. (Default: 0)
1496 [[AutomapHostsOnResolve]] **AutomapHostsOnResolve** **0**|**1**::
1497 When this option is enabled, and we get a request to resolve an address
1498 that ends with one of the suffixes in **AutomapHostsSuffixes**, we map an
1499 unused virtual address to that address, and return the new virtual address.
1500 This is handy for making ".onion" addresses work with applications that
1501 resolve an address and then connect to it. (Default: 0)
1503 [[AutomapHostsSuffixes]] **AutomapHostsSuffixes** __SUFFIX__,__SUFFIX__,__...__::
1504 A comma-separated list of suffixes to use with **AutomapHostsOnResolve**.
1505 The "." suffix is equivalent to "all addresses." (Default: .exit,.onion).
1507 [[DNSPort]] **DNSPort** \['address':]__port__|**auto** [_isolation flags_]::
1508 If non-zero, open this port to listen for UDP DNS requests, and resolve
1509 them anonymously. This port only handles A, AAAA, and PTR requests---it
1510 doesn't handle arbitrary DNS request types. Set the port to "auto" to
1511 have Tor pick a port for
1512 you. This directive can be specified multiple times to bind to multiple
1513 addresses/ports. See SocksPort for an explanation of isolation
1516 [[ClientDNSRejectInternalAddresses]] **ClientDNSRejectInternalAddresses** **0**|**1**::
1517 If true, Tor does not believe any anonymously retrieved DNS answer that
1518 tells it that an address resolves to an internal address (like 127.0.0.1 or
1519 192.168.0.1). This option prevents certain browser-based attacks; it
1520 is not allowed to be set on the default network. (Default: 1)
1522 [[ClientRejectInternalAddresses]] **ClientRejectInternalAddresses** **0**|**1**::
1523 If true, Tor does not try to fulfill requests to connect to an internal
1524 address (like 127.0.0.1 or 192.168.0.1) __unless an exit node is
1525 specifically requested__ (for example, via a .exit hostname, or a
1526 controller request). If true, multicast DNS hostnames for machines on the
1527 local network (of the form *.local) are also rejected. (Default: 1)
1529 [[DownloadExtraInfo]] **DownloadExtraInfo** **0**|**1**::
1530 If true, Tor downloads and caches "extra-info" documents. These documents
1531 contain information about servers other than the information in their
1532 regular server descriptors. Tor does not use this information for anything
1533 itself; to save bandwidth, leave this option turned off. (Default: 0)
1535 [[WarnPlaintextPorts]] **WarnPlaintextPorts** __port__,__port__,__...__::
1536 Tells Tor to issue a warnings whenever the user tries to make an anonymous
1537 connection to one of these ports. This option is designed to alert users
1538 to services that risk sending passwords in the clear. (Default:
1541 [[RejectPlaintextPorts]] **RejectPlaintextPorts** __port__,__port__,__...__::
1542 Like WarnPlaintextPorts, but instead of warning about risky port uses, Tor
1543 will instead refuse to make the connection. (Default: None)
1545 [[OptimisticData]] **OptimisticData** **0**|**1**|**auto**::
1546 When this option is set, and Tor is using an exit node that supports
1547 the feature, it will try optimistically to send data to the exit node
1548 without waiting for the exit node to report whether the connection
1549 succeeded. This can save a round-trip time for protocols like HTTP
1550 where the client talks first. If OptimisticData is set to **auto**,
1551 Tor will look at the UseOptimisticData parameter in the networkstatus.
1554 [[HSLayer2Nodes]] **HSLayer2Nodes** __node__,__node__,__...__::
1555 A list of identity fingerprints, nicknames, country codes, and
1556 address patterns of nodes that are allowed to be used as the
1557 second hop in all client or service-side Onion Service circuits.
1558 This option mitigates attacks where the adversary runs middle nodes
1559 and induces your client or service to create many circuits, in order
1560 to discover your primary guard node.
1561 (Default: Any node in the network may be used in the second hop.)
1564 HSLayer2Nodes ABCD1234CDEF5678ABCD1234CDEF5678ABCD1234, \{cc}, 255.254.0.0/8) +
1566 When this is set, the resulting hidden service paths will
1569 C - G - L2 - M - Rend +
1570 C - G - L2 - M - HSDir +
1571 C - G - L2 - M - Intro +
1572 S - G - L2 - M - Rend +
1573 S - G - L2 - M - HSDir +
1574 S - G - L2 - M - Intro +
1576 where C is this client, S is the service, G is the Guard node,
1577 L2 is a node from this option, and M is a random middle node.
1578 Rend, HSDir, and Intro point selection is not affected by this
1581 This option may be combined with HSLayer3Nodes to create
1584 C - G - L2 - L3 - Rend +
1585 C - G - L2 - L3 - M - HSDir +
1586 C - G - L2 - L3 - M - Intro +
1587 S - G - L2 - L3 - M - Rend +
1588 S - G - L2 - L3 - HSDir +
1589 S - G - L2 - L3 - Intro +
1591 ExcludeNodes have higher priority than HSLayer2Nodes,
1592 which means that nodes specified in ExcludeNodes will not be
1595 When either this option or HSLayer3Nodes are set, the /16 subnet
1596 and node family restrictions are removed for hidden service
1597 circuits. Additionally, we allow the guard node to be present
1598 as the Rend, HSDir, and IP node, and as the hop before it. This
1599 is done to prevent the adversary from inferring information
1600 about our guard, layer2, and layer3 node choices at later points
1603 This option is meant to be managed by a Tor controller such as
1604 https://github.com/mikeperry-tor/vanguards that selects and
1605 updates this set of nodes for you. Hence it does not do load
1606 balancing if fewer than 20 nodes are selected, and if no nodes in
1607 HSLayer2Nodes are currently available for use, Tor will not work.
1608 Please use extreme care if you are setting this option manually.
1610 [[HSLayer3Nodes]] **HSLayer3Nodes** __node__,__node__,__...__::
1611 A list of identity fingerprints, nicknames, country codes, and
1612 address patterns of nodes that are allowed to be used as the
1613 third hop in all client and service-side Onion Service circuits.
1614 This option mitigates attacks where the adversary runs middle nodes
1615 and induces your client or service to create many circuits, in order
1616 to discover your primary or Layer2 guard nodes.
1617 (Default: Any node in the network may be used in the third hop.)
1620 HSLayer3Nodes ABCD1234CDEF5678ABCD1234CDEF5678ABCD1234, \{cc}, 255.254.0.0/8) +
1622 When this is set by itself, the resulting hidden service paths
1624 C - G - M - L3 - Rend +
1625 C - G - M - L3 - M - HSDir +
1626 C - G - M - L3 - M - Intro +
1627 S - G - M - L3 - M - Rend +
1628 S - G - M - L3 - HSDir +
1629 S - G - M - L3 - Intro +
1630 where C is this client, S is the service, G is the Guard node,
1631 L2 is a node from this option, and M is a random middle node.
1632 Rend, HSDir, and Intro point selection is not affected by this
1635 While it is possible to use this option by itself, it should be
1636 combined with HSLayer2Nodes to create paths of the form:
1638 C - G - L2 - L3 - Rend +
1639 C - G - L2 - L3 - M - HSDir +
1640 C - G - L2 - L3 - M - Intro +
1641 S - G - L2 - L3 - M - Rend +
1642 S - G - L2 - L3 - HSDir +
1643 S - G - L2 - L3 - Intro +
1645 ExcludeNodes have higher priority than HSLayer3Nodes,
1646 which means that nodes specified in ExcludeNodes will not be
1649 When either this option or HSLayer2Nodes are set, the /16 subnet
1650 and node family restrictions are removed for hidden service
1651 circuits. Additionally, we allow the guard node to be present
1652 as the Rend, HSDir, and IP node, and as the hop before it. This
1653 is done to prevent the adversary from inferring information
1654 about our guard, layer2, and layer3 node choices at later points
1657 This option is meant to be managed by a Tor controller such as
1658 https://github.com/mikeperry-tor/vanguards that selects and
1659 updates this set of nodes for you. Hence it does not do load
1660 balancing if fewer than 20 nodes are selected, and if no nodes in
1661 HSLayer3Nodes are currently available for use, Tor will not work.
1662 Please use extreme care if you are setting this option manually.
1664 [[UseMicrodescriptors]] **UseMicrodescriptors** **0**|**1**|**auto**::
1665 Microdescriptors are a smaller version of the information that Tor needs
1666 in order to build its circuits. Using microdescriptors makes Tor clients
1667 download less directory information, thus saving bandwidth. Directory
1668 caches need to fetch regular descriptors and microdescriptors, so this
1669 option doesn't save any bandwidth for them. For legacy reasons, auto is
1670 accepted, but it has the same effect as 1. (Default: auto)
1672 [[PathBiasCircThreshold]] **PathBiasCircThreshold** __NUM__ +
1674 [[PathBiasNoticeRate]] **PathBiasNoticeRate** __NUM__ +
1676 [[PathBiasWarnRate]] **PathBiasWarnRate** __NUM__ +
1678 [[PathBiasExtremeRate]] **PathBiasExtremeRate** __NUM__ +
1680 [[PathBiasDropGuards]] **PathBiasDropGuards** __NUM__ +
1682 [[PathBiasScaleThreshold]] **PathBiasScaleThreshold** __NUM__::
1683 These options override the default behavior of Tor's (**currently
1684 experimental**) path bias detection algorithm. To try to find broken or
1685 misbehaving guard nodes, Tor looks for nodes where more than a certain
1686 fraction of circuits through that guard fail to get built. +
1688 The PathBiasCircThreshold option controls how many circuits we need to build
1689 through a guard before we make these checks. The PathBiasNoticeRate,
1690 PathBiasWarnRate and PathBiasExtremeRate options control what fraction of
1691 circuits must succeed through a guard so we won't write log messages.
1692 If less than PathBiasExtremeRate circuits succeed *and* PathBiasDropGuards
1693 is set to 1, we disable use of that guard. +
1695 When we have seen more than PathBiasScaleThreshold
1696 circuits through a guard, we scale our observations by 0.5 (governed by
1697 the consensus) so that new observations don't get swamped by old ones. +
1699 By default, or if a negative value is provided for one of these options,
1700 Tor uses reasonable defaults from the networkstatus consensus document.
1701 If no defaults are available there, these options default to 150, .70,
1702 .50, .30, 0, and 300 respectively.
1704 [[PathBiasUseThreshold]] **PathBiasUseThreshold** __NUM__ +
1706 [[PathBiasNoticeUseRate]] **PathBiasNoticeUseRate** __NUM__ +
1708 [[PathBiasExtremeUseRate]] **PathBiasExtremeUseRate** __NUM__ +
1710 [[PathBiasScaleUseThreshold]] **PathBiasScaleUseThreshold** __NUM__::
1711 Similar to the above options, these options override the default behavior
1712 of Tor's (**currently experimental**) path use bias detection algorithm. +
1714 Where as the path bias parameters govern thresholds for successfully
1715 building circuits, these four path use bias parameters govern thresholds
1716 only for circuit usage. Circuits which receive no stream usage
1717 are not counted by this detection algorithm. A used circuit is considered
1718 successful if it is capable of carrying streams or otherwise receiving
1719 well-formed responses to RELAY cells. +
1721 By default, or if a negative value is provided for one of these options,
1722 Tor uses reasonable defaults from the networkstatus consensus document.
1723 If no defaults are available there, these options default to 20, .80,
1724 .60, and 100, respectively.
1726 [[ClientUseIPv4]] **ClientUseIPv4** **0**|**1**::
1727 If this option is set to 0, Tor will avoid connecting to directory servers
1728 and entry nodes over IPv4. Note that clients with an IPv4
1729 address in a **Bridge**, proxy, or pluggable transport line will try
1730 connecting over IPv4 even if **ClientUseIPv4** is set to 0. (Default: 1)
1732 [[ClientUseIPv6]] **ClientUseIPv6** **0**|**1**::
1733 If this option is set to 1, Tor might connect to directory servers or
1734 entry nodes over IPv6. For IPv6 only hosts, you need to also set
1735 **ClientUseIPv4** to 0 to disable IPv4. Note that clients configured with
1736 an IPv6 address in a **Bridge**, proxy, or pluggable transportline will
1737 try connecting over IPv6 even if **ClientUseIPv6** is set to 0. (Default: 0)
1739 [[ClientPreferIPv6DirPort]] **ClientPreferIPv6DirPort** **0**|**1**|**auto**::
1740 If this option is set to 1, Tor prefers a directory port with an IPv6
1741 address over one with IPv4, for direct connections, if a given directory
1742 server has both. (Tor also prefers an IPv6 DirPort if IPv4Client is set to
1743 0.) If this option is set to auto, clients prefer IPv4. Other things may
1744 influence the choice. This option breaks a tie to the favor of IPv6.
1745 (Default: auto) (DEPRECATED: This option has had no effect for some
1748 [[ClientPreferIPv6ORPort]] **ClientPreferIPv6ORPort** **0**|**1**|**auto**::
1749 If this option is set to 1, Tor prefers an OR port with an IPv6
1750 address over one with IPv4 if a given entry node has both. (Tor also
1751 prefers an IPv6 ORPort if IPv4Client is set to 0.) If this option is set
1752 to auto, Tor bridge clients prefer the configured bridge address, and
1753 other clients prefer IPv4. Other things may influence the choice. This
1754 option breaks a tie to the favor of IPv6. (Default: auto)
1756 [[PathsNeededToBuildCircuits]] **PathsNeededToBuildCircuits** __NUM__::
1757 Tor clients don't build circuits for user traffic until they know
1758 about enough of the network so that they could potentially construct
1759 enough of the possible paths through the network. If this option
1760 is set to a fraction between 0.25 and 0.95, Tor won't build circuits
1761 until it has enough descriptors or microdescriptors to construct
1762 that fraction of possible paths. Note that setting this option too low
1763 can make your Tor client less anonymous, and setting it too high can
1764 prevent your Tor client from bootstrapping. If this option is negative,
1765 Tor will use a default value chosen by the directory authorities. If the
1766 directory authorities do not choose a value, Tor will default to 0.6.
1769 [[ClientBootstrapConsensusAuthorityDownloadInitialDelay]] **ClientBootstrapConsensusAuthorityDownloadInitialDelay** __N__::
1770 Initial delay in seconds for when clients should download consensuses from authorities
1771 if they are bootstrapping (that is, they don't have a usable, reasonably
1772 live consensus). Only used by clients fetching from a list of fallback
1773 directory mirrors. This schedule is advanced by (potentially concurrent)
1774 connection attempts, unlike other schedules, which are advanced by
1775 connection failures. (Default: 6)
1777 [[ClientBootstrapConsensusFallbackDownloadInitialDelay]] **ClientBootstrapConsensusFallbackDownloadInitialDelay** __N__::
1778 Initial delay in seconds for when clients should download consensuses from fallback
1779 directory mirrors if they are bootstrapping (that is, they don't have a
1780 usable, reasonably live consensus). Only used by clients fetching from a
1781 list of fallback directory mirrors. This schedule is advanced by
1782 (potentially concurrent) connection attempts, unlike other schedules,
1783 which are advanced by connection failures. (Default: 0)
1785 [[ClientBootstrapConsensusAuthorityOnlyDownloadInitialDelay]] **ClientBootstrapConsensusAuthorityOnlyDownloadInitialDelay** __N__::
1786 Initial delay in seconds for when clients should download consensuses from authorities
1787 if they are bootstrapping (that is, they don't have a usable, reasonably
1788 live consensus). Only used by clients which don't have or won't fetch
1789 from a list of fallback directory mirrors. This schedule is advanced by
1790 (potentially concurrent) connection attempts, unlike other schedules,
1791 which are advanced by connection failures. (Default: 0)
1793 [[ClientBootstrapConsensusMaxInProgressTries]] **ClientBootstrapConsensusMaxInProgressTries** __NUM__::
1794 Try this many simultaneous connections to download a consensus before
1795 waiting for one to complete, timeout, or error out. (Default: 3)
1800 The following options are useful only for servers (that is, if ORPort
1803 [[Address]] **Address** __address__::
1804 The IPv4 address of this server, or a fully qualified domain name of
1805 this server that resolves to an IPv4 address. You can leave this
1806 unset, and Tor will try to guess your IPv4 address. This IPv4
1807 address is the one used to tell clients and other servers where to
1808 find your Tor server; it doesn't affect the address that your server
1809 binds to. To bind to a different address, use the ORPort and
1810 OutboundBindAddress options.
1812 [[AssumeReachable]] **AssumeReachable** **0**|**1**::
1813 This option is used when bootstrapping a new Tor network. If set to 1,
1814 don't do self-reachability testing; just upload your server descriptor
1815 immediately. If **AuthoritativeDirectory** is also set, this option
1816 instructs the dirserver to bypass remote reachability testing too and list
1817 all connected servers as running.
1819 [[BridgeRelay]] **BridgeRelay** **0**|**1**::
1820 Sets the relay to act as a "bridge" with respect to relaying connections
1821 from bridge users to the Tor network. It mainly causes Tor to publish a
1822 server descriptor to the bridge database, rather than
1823 to the public directory authorities. +
1825 Note: make sure that no MyFamily lines are present in your torrc when
1826 relay is configured in bridge mode.
1828 [[BridgeDistribution]] **BridgeDistribution** __string__::
1829 If set along with BridgeRelay, Tor will include a new line in its
1830 bridge descriptor which indicates to the BridgeDB service how it
1831 would like its bridge address to be given out. Set it to "none" if
1832 you want BridgeDB to avoid distributing your bridge address, or "any" to
1833 let BridgeDB decide. (Default: any)
1835 Note: as of Oct 2017, the BridgeDB part of this option is not yet
1836 implemented. Until BridgeDB is updated to obey this option, your
1837 bridge will make this request, but it will not (yet) be obeyed.
1839 [[ContactInfo]] **ContactInfo** __email_address__::
1840 Administrative contact information for this relay or bridge. This line
1841 can be used to contact you if your relay or bridge is misconfigured or
1842 something else goes wrong. Note that we archive and publish all
1843 descriptors containing these lines and that Google indexes them, so
1844 spammers might also collect them. You may want to obscure the fact
1845 that it's an email address and/or generate a new address for this
1848 ContactInfo **must** be set to a working address if you run more than one
1849 relay or bridge. (Really, everybody running a relay or bridge should set
1853 [[ExitRelay]] **ExitRelay** **0**|**1**|**auto**::
1854 Tells Tor whether to run as an exit relay. If Tor is running as a
1855 non-bridge server, and ExitRelay is set to 1, then Tor allows traffic to
1856 exit according to the ExitPolicy option, the ReducedExitPolicy option,
1857 or the default ExitPolicy (if no other exit policy option is specified). +
1859 If ExitRelay is set to 0, no traffic is allowed to
1860 exit, and the ExitPolicy and ReducedExitPolicy options are ignored. +
1862 If ExitRelay is set to "auto", then Tor checks the ExitPolicy and
1863 ReducedExitPolicy options. If either is set, Tor behaves as if ExitRelay
1864 were set to 1. If neither exit policy option is set, Tor behaves as if
1865 ExitRelay were set to 0. (Default: auto)
1867 [[ExitPolicy]] **ExitPolicy** __policy__,__policy__,__...__::
1868 Set an exit policy for this server. Each policy is of the form
1869 "**accept[6]**|**reject[6]** __ADDR__[/__MASK__][:__PORT__]". If /__MASK__ is
1870 omitted then this policy just applies to the host given. Instead of giving
1871 a host or network you can also use "\*" to denote the universe (0.0.0.0/0
1872 and ::/0), or \*4 to denote all IPv4 addresses, and \*6 to denote all IPv6
1874 __PORT__ can be a single port number, an interval of ports
1875 "__FROM_PORT__-__TO_PORT__", or "\*". If __PORT__ is omitted, that means
1878 For example, "accept 18.7.22.69:\*,reject 18.0.0.0/8:\*,accept \*:\*" would
1879 reject any IPv4 traffic destined for MIT except for web.mit.edu, and accept
1880 any other IPv4 or IPv6 traffic. +
1882 Tor also allows IPv6 exit policy entries. For instance, "reject6 [FC00::]/7:\*"
1883 rejects all destinations that share 7 most significant bit prefix with
1884 address FC00::. Respectively, "accept6 [C000::]/3:\*" accepts all destinations
1885 that share 3 most significant bit prefix with address C000::. +
1887 accept6 and reject6 only produce IPv6 exit policy entries. Using an IPv4
1888 address with accept6 or reject6 is ignored and generates a warning.
1889 accept/reject allows either IPv4 or IPv6 addresses. Use \*4 as an IPv4
1890 wildcard address, and \*6 as an IPv6 wildcard address. accept/reject *
1891 expands to matching IPv4 and IPv6 wildcard address rules. +
1893 To specify all IPv4 and IPv6 internal and link-local networks (including
1894 0.0.0.0/8, 169.254.0.0/16, 127.0.0.0/8, 192.168.0.0/16, 10.0.0.0/8,
1895 172.16.0.0/12, [::]/8, [FC00::]/7, [FE80::]/10, [FEC0::]/10, [FF00::]/8,
1896 and [::]/127), you can use the "private" alias instead of an address.
1897 ("private" always produces rules for IPv4 and IPv6 addresses, even when
1898 used with accept6/reject6.) +
1900 Private addresses are rejected by default (at the beginning of your exit
1901 policy), along with any configured primary public IPv4 and IPv6 addresses.
1902 These private addresses are rejected unless you set the
1903 ExitPolicyRejectPrivate config option to 0. For example, once you've done
1904 that, you could allow HTTP to 127.0.0.1 and block all other connections to
1905 internal networks with "accept 127.0.0.1:80,reject private:\*", though that
1906 may also allow connections to your own computer that are addressed to its
1907 public (external) IP address. See RFC 1918 and RFC 3330 for more details
1908 about internal and reserved IP address space. See
1909 ExitPolicyRejectLocalInterfaces if you want to block every address on the
1910 relay, even those that aren't advertised in the descriptor. +
1912 This directive can be specified multiple times so you don't have to put it
1915 Policies are considered first to last, and the first match wins. If you
1916 want to allow the same ports on IPv4 and IPv6, write your rules using
1917 accept/reject \*. If you want to allow different ports on IPv4 and IPv6,
1918 write your IPv6 rules using accept6/reject6 \*6, and your IPv4 rules using
1919 accept/reject \*4. If you want to \_replace_ the default exit policy, end
1920 your exit policy with either a reject \*:* or an accept \*:*. Otherwise,
1921 you're \_augmenting_ (prepending to) the default exit policy. +
1923 If you want to use a reduced exit policy rather than the default exit
1924 policy, set "ReducedExitPolicy 1". If you want to _replace_ the default
1925 exit policy with your custom exit policy, end your exit policy with either
1926 a reject *:* or an accept *:*. Otherwise, you're _augmenting_ (prepending
1927 to) the default or reduced exit policy. +
1929 The default exit policy is:
1943 // Anchor only for formatting, not visible in the man page.
1944 [[ExitPolicyDefault]]::
1945 Since the default exit policy uses accept/reject *, it applies to both
1946 IPv4 and IPv6 addresses.
1948 [[ExitPolicyRejectPrivate]] **ExitPolicyRejectPrivate** **0**|**1**::
1949 Reject all private (local) networks, along with the relay's advertised
1950 public IPv4 and IPv6 addresses, at the beginning of your exit policy.
1951 See above entry on ExitPolicy.
1954 [[ExitPolicyRejectLocalInterfaces]] **ExitPolicyRejectLocalInterfaces** **0**|**1**::
1955 Reject all IPv4 and IPv6 addresses that the relay knows about, at the
1956 beginning of your exit policy. This includes any OutboundBindAddress, the
1957 bind addresses of any port options, such as ControlPort or DNSPort, and any
1958 public IPv4 and IPv6 addresses on any interface on the relay. (If IPv6Exit
1959 is not set, all IPv6 addresses will be rejected anyway.)
1960 See above entry on ExitPolicy.
1961 This option is off by default, because it lists all public relay IP
1962 addresses in the ExitPolicy, even those relay operators might prefer not
1966 [[ReducedExitPolicy]] **ReducedExitPolicy** **0**|**1**::
1967 If set, use a reduced exit policy rather than the default one. +
1969 The reduced exit policy is an alternative to the default exit policy. It
1970 allows as many Internet services as possible while still blocking the
1971 majority of TCP ports. Currently, the policy allows approximately 65 ports.
1972 This reduces the odds that your node will be used for peer-to-peer
1975 The reduced exit policy is:
2059 [[IPv6Exit]] **IPv6Exit** **0**|**1**::
2060 If set, and we are an exit node, allow clients to use us for IPv6
2061 traffic. (Default: 0)
2063 [[MaxOnionQueueDelay]] **MaxOnionQueueDelay** __NUM__ [**msec**|**second**]::
2064 If we have more onionskins queued for processing than we can process in
2065 this amount of time, reject new ones. (Default: 1750 msec)
2067 [[MyFamily]] **MyFamily** __fingerprint__,__fingerprint__,...::
2068 Declare that this Tor relay is controlled or administered by a group or
2069 organization identical or similar to that of the other relays, defined by
2070 their (possibly $-prefixed) identity fingerprints.
2071 This option can be repeated many times, for
2072 convenience in defining large families: all fingerprints in all MyFamily
2073 lines are merged into one list.
2074 When two relays both declare that they are in the
2075 same \'family', Tor clients will not use them in the same circuit. (Each
2076 relay only needs to list the other servers in its family; it doesn't need to
2077 list itself, but it won't hurt if it does.) Do not list any bridge relay as it would
2078 compromise its concealment. +
2080 When listing a node, it's better to list it by fingerprint than by
2081 nickname: fingerprints are more reliable. +
2083 If you run more than one relay, the MyFamily option on each relay
2084 **must** list all other relays, as described above. +
2086 Note: do not use MyFamily when configuring your Tor instance as a
2089 [[Nickname]] **Nickname** __name__::
2090 Set the server's nickname to \'name'. Nicknames must be between 1 and 19
2091 characters inclusive, and must contain only the characters [a-zA-Z0-9].
2092 If not set, **Unnamed** will be used. Relays can always be uniquely identified
2093 by their identity fingerprints.
2095 [[NumCPUs]] **NumCPUs** __num__::
2096 How many processes to use at once for decrypting onionskins and other
2097 parallelizable operations. If this is set to 0, Tor will try to detect
2098 how many CPUs you have, defaulting to 1 if it can't tell. (Default: 0)
2100 [[ORPort]] **ORPort** \['address':]__PORT__|**auto** [_flags_]::
2101 Advertise this port to listen for connections from Tor clients and
2102 servers. This option is required to be a Tor server.
2103 Set it to "auto" to have Tor pick a port for you. Set it to 0 to not
2104 run an ORPort at all. This option can occur more than once. (Default: 0) +
2106 Tor recognizes these flags on each ORPort:
2108 By default, we bind to a port and tell our users about it. If
2109 NoAdvertise is specified, we don't advertise, but listen anyway. This
2110 can be useful if the port everybody will be connecting to (for
2111 example, one that's opened on our firewall) is somewhere else.
2113 By default, we bind to a port and tell our users about it. If
2114 NoListen is specified, we don't bind, but advertise anyway. This
2115 can be useful if something else (for example, a firewall's port
2116 forwarding configuration) is causing connections to reach us.
2118 If the address is absent, or resolves to both an IPv4 and an IPv6
2119 address, only listen to the IPv4 address.
2121 If the address is absent, or resolves to both an IPv4 and an IPv6
2122 address, only listen to the IPv6 address.
2124 // Anchor only for formatting, not visible in the man page.
2125 [[ORPortFlagsExclusive]]::
2126 For obvious reasons, NoAdvertise and NoListen are mutually exclusive, and
2127 IPv4Only and IPv6Only are mutually exclusive.
2129 [[PublishServerDescriptor]] **PublishServerDescriptor** **0**|**1**|**v3**|**bridge**,**...**::
2130 This option specifies which descriptors Tor will publish when acting as
2132 choose multiple arguments, separated by commas. +
2134 If this option is set to 0, Tor will not publish its
2135 descriptors to any directories. (This is useful if you're testing
2136 out your server, or if you're using a Tor controller that handles
2137 directory publishing for you.) Otherwise, Tor will publish its
2138 descriptors of all type(s) specified. The default is "1", which
2139 means "if running as a relay or bridge, publish descriptors to the
2140 appropriate authorities". Other possibilities are "v3", meaning
2141 "publish as if you're a relay", and "bridge", meaning "publish as
2142 if you're a bridge".
2144 [[ShutdownWaitLength]] **ShutdownWaitLength** __NUM__::
2145 When we get a SIGINT and we're a server, we begin shutting down:
2146 we close listeners and start refusing new circuits. After **NUM**
2147 seconds, we exit. If we get a second SIGINT, we exit immediately.
2148 (Default: 30 seconds)
2150 [[SSLKeyLifetime]] **SSLKeyLifetime** __N__ **minutes**|**hours**|**days**|**weeks**::
2151 When creating a link certificate for our outermost SSL handshake,
2152 set its lifetime to this amount of time. If set to 0, Tor will choose
2153 some reasonable random defaults. (Default: 0)
2155 [[HeartbeatPeriod]] **HeartbeatPeriod** __N__ **minutes**|**hours**|**days**|**weeks**::
2156 Log a heartbeat message every **HeartbeatPeriod** seconds. This is
2157 a log level __notice__ message, designed to let you know your Tor
2158 server is still alive and doing useful things. Settings this
2159 to 0 will disable the heartbeat. Otherwise, it must be at least 30
2160 minutes. (Default: 6 hours)
2162 [[MainloopStats]] **MainloopStats** **0**|**1**::
2163 Log main loop statistics every **HeartbeatPeriod** seconds. This is a log
2164 level __notice__ message designed to help developers instrumenting Tor's
2165 main event loop. (Default: 0)
2167 [[AccountingMax]] **AccountingMax** __N__ **bytes**|**KBytes**|**MBytes**|**GBytes**|**TBytes**|**KBits**|**MBits**|**GBits**|**TBits**::
2168 Limits the max number of bytes sent and received within a set time period
2169 using a given calculation rule (see: AccountingStart, AccountingRule).
2170 Useful if you need to stay under a specific bandwidth. By default, the
2171 number used for calculation is the max of either the bytes sent or
2172 received. For example, with AccountingMax set to 1 GByte, a server
2173 could send 900 MBytes and receive 800 MBytes and continue running.
2174 It will only hibernate once one of the two reaches 1 GByte. This can
2175 be changed to use the sum of the both bytes received and sent by setting
2176 the AccountingRule option to "sum" (total bandwidth in/out). When the
2177 number of bytes remaining gets low, Tor will stop accepting new connections
2178 and circuits. When the number of bytes is exhausted, Tor will hibernate
2179 until some time in the next accounting period. To prevent all servers
2180 from waking at the same time, Tor will also wait until a random point
2181 in each period before waking up. If you have bandwidth cost issues,
2182 enabling hibernation is preferable to setting a low bandwidth, since
2183 it provides users with a collection of fast servers that are up some
2184 of the time, which is more useful than a set of slow servers that are
2187 [[AccountingRule]] **AccountingRule** **sum**|**max**|**in**|**out**::
2188 How we determine when our AccountingMax has been reached (when we
2189 should hibernate) during a time interval. Set to "max" to calculate
2190 using the higher of either the sent or received bytes (this is the
2191 default functionality). Set to "sum" to calculate using the sent
2192 plus received bytes. Set to "in" to calculate using only the
2193 received bytes. Set to "out" to calculate using only the sent bytes.
2196 [[AccountingStart]] **AccountingStart** **day**|**week**|**month** [__day__] __HH:MM__::
2197 Specify how long accounting periods last. If **month** is given,
2198 each accounting period runs from the time __HH:MM__ on the __dayth__ day of one
2199 month to the same day and time of the next. The relay will go at full speed,
2200 use all the quota you specify, then hibernate for the rest of the period. (The
2201 day must be between 1 and 28.) If **week** is given, each accounting period
2202 runs from the time __HH:MM__ of the __dayth__ day of one week to the same day
2203 and time of the next week, with Monday as day 1 and Sunday as day 7. If **day**
2204 is given, each accounting period runs from the time __HH:MM__ each day to the
2205 same time on the next day. All times are local, and given in 24-hour time.
2206 (Default: "month 1 0:00")
2208 [[RefuseUnknownExits]] **RefuseUnknownExits** **0**|**1**|**auto**::
2209 Prevent nodes that don't appear in the consensus from exiting using this
2210 relay. If the option is 1, we always block exit attempts from such
2211 nodes; if it's 0, we never do, and if the option is "auto", then we do
2212 whatever the authorities suggest in the consensus (and block if the consensus
2213 is quiet on the issue). (Default: auto)
2215 [[ServerDNSResolvConfFile]] **ServerDNSResolvConfFile** __filename__::
2216 Overrides the default DNS configuration with the configuration in
2217 __filename__. The file format is the same as the standard Unix
2218 "**resolv.conf**" file (7). This option, like all other ServerDNS options,
2219 only affects name lookups that your server does on behalf of clients.
2220 (Defaults to use the system DNS configuration.)
2222 [[ServerDNSAllowBrokenConfig]] **ServerDNSAllowBrokenConfig** **0**|**1**::
2223 If this option is false, Tor exits immediately if there are problems
2224 parsing the system DNS configuration or connecting to nameservers.
2225 Otherwise, Tor continues to periodically retry the system nameservers until
2226 it eventually succeeds. (Default: 1)
2228 [[ServerDNSSearchDomains]] **ServerDNSSearchDomains** **0**|**1**::
2229 If set to 1, then we will search for addresses in the local search domain.
2230 For example, if this system is configured to believe it is in
2231 "example.com", and a client tries to connect to "www", the client will be
2232 connected to "www.example.com". This option only affects name lookups that
2233 your server does on behalf of clients. (Default: 0)
2235 [[ServerDNSDetectHijacking]] **ServerDNSDetectHijacking** **0**|**1**::
2236 When this option is set to 1, we will test periodically to determine
2237 whether our local nameservers have been configured to hijack failing DNS
2238 requests (usually to an advertising site). If they are, we will attempt to
2239 correct this. This option only affects name lookups that your server does
2240 on behalf of clients. (Default: 1)
2242 [[ServerDNSTestAddresses]] **ServerDNSTestAddresses** __hostname__,__hostname__,__...__::
2243 When we're detecting DNS hijacking, make sure that these __valid__ addresses
2244 aren't getting redirected. If they are, then our DNS is completely useless,
2245 and we'll reset our exit policy to "reject \*:*". This option only affects
2246 name lookups that your server does on behalf of clients. (Default:
2247 "www.google.com, www.mit.edu, www.yahoo.com, www.slashdot.org")
2249 [[ServerDNSAllowNonRFC953Hostnames]] **ServerDNSAllowNonRFC953Hostnames** **0**|**1**::
2250 When this option is disabled, Tor does not try to resolve hostnames
2251 containing illegal characters (like @ and :) rather than sending them to an
2252 exit node to be resolved. This helps trap accidental attempts to resolve
2253 URLs and so on. This option only affects name lookups that your server does
2254 on behalf of clients. (Default: 0)
2256 [[BridgeRecordUsageByCountry]] **BridgeRecordUsageByCountry** **0**|**1**::
2257 When this option is enabled and BridgeRelay is also enabled, and we have
2258 GeoIP data, Tor keeps a per-country count of how many client
2259 addresses have contacted it so that it can help the bridge authority guess
2260 which countries have blocked access to it. (Default: 1)
2262 [[ServerDNSRandomizeCase]] **ServerDNSRandomizeCase** **0**|**1**::
2263 When this option is set, Tor sets the case of each character randomly in
2264 outgoing DNS requests, and makes sure that the case matches in DNS replies.
2265 This so-called "0x20 hack" helps resist some types of DNS poisoning attack.
2266 For more information, see "Increased DNS Forgery Resistance through
2267 0x20-Bit Encoding". This option only affects name lookups that your server
2268 does on behalf of clients. (Default: 1)
2270 [[GeoIPFile]] **GeoIPFile** __filename__::
2271 A filename containing IPv4 GeoIP data, for use with by-country statistics.
2273 [[GeoIPv6File]] **GeoIPv6File** __filename__::
2274 A filename containing IPv6 GeoIP data, for use with by-country statistics.
2276 [[CellStatistics]] **CellStatistics** **0**|**1**::
2278 When this option is enabled, Tor collects statistics about cell
2279 processing (i.e. mean time a cell is spending in a queue, mean
2280 number of cells in a queue and mean number of processed cells per
2281 circuit) and writes them into disk every 24 hours. Onion router
2282 operators may use the statistics for performance monitoring.
2283 If ExtraInfoStatistics is enabled, it will published as part of
2284 extra-info document. (Default: 0)
2286 [[PaddingStatistics]] **PaddingStatistics** **0**|**1**::
2287 Relays and bridges only.
2288 When this option is enabled, Tor collects statistics for padding cells
2289 sent and received by this relay, in addition to total cell counts.
2290 These statistics are rounded, and omitted if traffic is low. This
2291 information is important for load balancing decisions related to padding.
2292 If ExtraInfoStatistics is enabled, it will be published
2293 as a part of extra-info document. (Default: 1)
2295 [[DirReqStatistics]] **DirReqStatistics** **0**|**1**::
2296 Relays and bridges only.
2297 When this option is enabled, a Tor directory writes statistics on the
2298 number and response time of network status requests to disk every 24
2299 hours. Enables relay and bridge operators to monitor how much their
2300 server is being used by clients to learn about Tor network.
2301 If ExtraInfoStatistics is enabled, it will published as part of
2302 extra-info document. (Default: 1)
2304 [[EntryStatistics]] **EntryStatistics** **0**|**1**::
2306 When this option is enabled, Tor writes statistics on the number of
2307 directly connecting clients to disk every 24 hours. Enables relay
2308 operators to monitor how much inbound traffic that originates from
2309 Tor clients passes through their server to go further down the
2310 Tor network. If ExtraInfoStatistics is enabled, it will be published
2311 as part of extra-info document. (Default: 0)
2313 [[ExitPortStatistics]] **ExitPortStatistics** **0**|**1**::
2315 When this option is enabled, Tor writes statistics on the number of
2316 relayed bytes and opened stream per exit port to disk every 24 hours.
2317 Enables exit relay operators to measure and monitor amounts of traffic
2318 that leaves Tor network through their exit node. If ExtraInfoStatistics
2319 is enabled, it will be published as part of extra-info document.
2322 [[ConnDirectionStatistics]] **ConnDirectionStatistics** **0**|**1**::
2324 When this option is enabled, Tor writes statistics on the amounts of
2325 traffic it passes between itself and other relays to disk every 24
2326 hours. Enables relay operators to monitor how much their relay is
2327 being used as middle node in the circuit. If ExtraInfoStatistics is
2328 enabled, it will be published as part of extra-info document.
2331 [[HiddenServiceStatistics]] **HiddenServiceStatistics** **0**|**1**::
2333 When this option is enabled, a Tor relay writes obfuscated
2334 statistics on its role as hidden-service directory, introduction
2335 point, or rendezvous point to disk every 24 hours. If
2336 ExtraInfoStatistics is also enabled, these statistics are further
2337 published to the directory authorities. (Default: 1)
2339 [[ExtraInfoStatistics]] **ExtraInfoStatistics** **0**|**1**::
2340 When this option is enabled, Tor includes previously gathered statistics in
2341 its extra-info documents that it uploads to the directory authorities.
2344 [[ExtendAllowPrivateAddresses]] **ExtendAllowPrivateAddresses** **0**|**1**::
2345 When this option is enabled, Tor will connect to relays on localhost,
2346 RFC1918 addresses, and so on. In particular, Tor will make direct OR
2347 connections, and Tor routers allow EXTEND requests, to these private
2348 addresses. (Tor will always allow connections to bridges, proxies, and
2349 pluggable transports configured on private addresses.) Enabling this
2350 option can create security issues; you should probably leave it off.
2353 [[MaxMemInQueues]] **MaxMemInQueues** __N__ **bytes**|**KB**|**MB**|**GB**::
2354 This option configures a threshold above which Tor will assume that it
2355 needs to stop queueing or buffering data because it's about to run out of
2356 memory. If it hits this threshold, it will begin killing circuits until
2357 it has recovered at least 10% of this memory. Do not set this option too
2358 low, or your relay may be unreliable under load. This option only
2359 affects some queues, so the actual process size will be larger than
2360 this. If this option is set to 0, Tor will try to pick a reasonable
2361 default based on your system's physical memory. (Default: 0)
2363 [[DisableOOSCheck]] **DisableOOSCheck** **0**|**1**::
2364 This option disables the code that closes connections when Tor notices
2365 that it is running low on sockets. Right now, it is on by default,
2366 since the existing out-of-sockets mechanism tends to kill OR connections
2367 more than it should. (Default: 1)
2369 [[SigningKeyLifetime]] **SigningKeyLifetime** __N__ **days**|**weeks**|**months**::
2370 For how long should each Ed25519 signing key be valid? Tor uses a
2371 permanent master identity key that can be kept offline, and periodically
2372 generates new "signing" keys that it uses online. This option
2373 configures their lifetime.
2376 [[OfflineMasterKey]] **OfflineMasterKey** **0**|**1**::
2377 If non-zero, the Tor relay will never generate or load its master secret
2378 key. Instead, you'll have to use "tor --keygen" to manage the permanent
2379 ed25519 master identity key, as well as the corresponding temporary
2380 signing keys and certificates. (Default: 0)
2382 [[KeyDirectory]] **KeyDirectory** __DIR__::
2383 Store secret keys in DIR. Can not be changed while tor is
2385 (Default: the "keys" subdirectory of DataDirectory.)
2387 [[KeyDirectoryGroupReadable]] **KeyDirectoryGroupReadable** **0**|**1**::
2388 If this option is set to 0, don't allow the filesystem group to read the
2389 KeywDirectory. If the option is set to 1, make the KeyDirectory readable
2390 by the default GID. (Default: 0)
2392 [[RephistTrackTime]] **RephistTrackTime** __N__ **seconds**|**minutes**|**hours**|**days**|**weeks**::
2393 Tells an authority, or other node tracking node reliability and history,
2394 that fine-grained information about nodes can be discarded when it hasn't
2395 changed for a given amount of time. (Default: 24 hours)
2398 DIRECTORY SERVER OPTIONS
2399 ------------------------
2401 The following options are useful only for directory servers. (Relays with
2402 enough bandwidth automatically become directory servers; see DirCache for
2405 [[DirPortFrontPage]] **DirPortFrontPage** __FILENAME__::
2406 When this option is set, it takes an HTML file and publishes it as "/" on
2407 the DirPort. Now relay operators can provide a disclaimer without needing
2408 to set up a separate webserver. There's a sample disclaimer in
2409 contrib/operator-tools/tor-exit-notice.html.
2411 [[DirPort]] **DirPort** \['address':]__PORT__|**auto** [_flags_]::
2412 If this option is nonzero, advertise the directory service on this port.
2413 Set it to "auto" to have Tor pick a port for you. This option can occur
2414 more than once, but only one advertised DirPort is supported: all
2415 but one DirPort must have the **NoAdvertise** flag set. (Default: 0) +
2417 The same flags are supported here as are supported by ORPort.
2419 [[DirPolicy]] **DirPolicy** __policy__,__policy__,__...__::
2420 Set an entrance policy for this server, to limit who can connect to the
2421 directory ports. The policies have the same form as exit policies above,
2422 except that port specifiers are ignored. Any address not matched by
2423 some entry in the policy is accepted.
2425 [[DirCache]] **DirCache** **0**|**1**::
2426 When this option is set, Tor caches all current directory documents except
2427 extra info documents, and accepts client requests for them. If
2428 **DownloadExtraInfo** is set, cached extra info documents are also cached.
2429 Setting **DirPort** is not required for **DirCache**, because clients
2430 connect via the ORPort by default. Setting either DirPort or BridgeRelay
2431 and setting DirCache to 0 is not supported. (Default: 1)
2433 [[MaxConsensusAgeForDiffs]] **MaxConsensusAgeForDiffs** __N__ **minutes**|**hours**|**days**|**weeks**::
2434 When this option is nonzero, Tor caches will not try to generate
2435 consensus diffs for any consensus older than this amount of time.
2436 If this option is set to zero, Tor will pick a reasonable default from
2437 the current networkstatus document. You should not set this
2438 option unless your cache is severely low on disk space or CPU.
2439 If you need to set it, keeping it above 3 or 4 hours will help clients
2440 much more than setting it to zero.
2444 DENIAL OF SERVICE MITIGATION OPTIONS
2445 ------------------------------------
2447 Tor has three built-in mitigation options that can be individually
2448 enabled/disabled and fine-tuned, but by default Tor directory authorities will
2449 define reasonable values for relays and no explicit configuration is required
2450 to make use of these protections. The mitigations take place at relays,
2453 1. If a single client address makes too many concurrent connections (this is
2454 configurable via DoSConnectionMaxConcurrentCount), hang up on further
2457 2. If a single client IP address (v4 or v6) makes circuits too quickly
2458 (default values are more than 3 per second, with an allowed burst of 90,
2459 see DoSCircuitCreationRate and DoSCircuitCreationBurst) while also having
2460 too many connections open (default is 3, see
2461 DoSCircuitCreationMinConnections), tor will refuse any new circuit (CREATE
2462 cells) for the next while (random value between 1 and 2 hours).
2464 3. If a client asks to establish a rendezvous point to you directly (ex:
2465 Tor2Web client), ignore the request.
2467 These defenses can be manually controlled by torrc options, but relays will
2468 also take guidance from consensus parameters using these same names, so there's
2469 no need to configure anything manually. In doubt, do not change those values.
2471 The values set by the consensus, if any, can be found here:
2472 https://consensus-health.torproject.org/#consensusparams
2474 If any of the DoS mitigations are enabled, a heartbeat message will appear in
2475 your log at NOTICE level which looks like:
2477 DoS mitigation since startup: 429042 circuits rejected, 17 marked addresses.
2478 2238 connections closed. 8052 single hop clients refused.
2480 The following options are useful only for a public relay. They control the
2481 Denial of Service mitigation subsystem described above.
2483 [[DoSCircuitCreationEnabled]] **DoSCircuitCreationEnabled** **0**|**1**|**auto**::
2485 Enable circuit creation DoS mitigation. If set to 1 (enabled), tor will
2486 cache client IPs along with statistics in order to detect circuit DoS
2487 attacks. If an address is positively identified, tor will activate
2488 defenses against the address. See the DoSCircuitCreationDefenseType option
2489 for more details. This is a client to relay detection only. "auto" means
2490 use the consensus parameter. If not defined in the consensus, the value is 0.
2493 [[DoSCircuitCreationMinConnections]] **DoSCircuitCreationMinConnections** __NUM__::
2495 Minimum threshold of concurrent connections before a client address can be
2496 flagged as executing a circuit creation DoS. In other words, once a client
2497 address reaches the circuit rate and has a minimum of NUM concurrent
2498 connections, a detection is positive. "0" means use the consensus
2499 parameter. If not defined in the consensus, the value is 3.
2502 [[DoSCircuitCreationRate]] **DoSCircuitCreationRate** __NUM__::
2504 The allowed circuit creation rate per second applied per client IP
2505 address. If this option is 0, it obeys a consensus parameter. If not
2506 defined in the consensus, the value is 3.
2509 [[DoSCircuitCreationBurst]] **DoSCircuitCreationBurst** __NUM__::
2511 The allowed circuit creation burst per client IP address. If the circuit
2512 rate and the burst are reached, a client is marked as executing a circuit
2513 creation DoS. "0" means use the consensus parameter. If not defined in the
2514 consensus, the value is 90.
2517 [[DoSCircuitCreationDefenseType]] **DoSCircuitCreationDefenseType** __NUM__::
2519 This is the type of defense applied to a detected client address. The
2520 possible values are:
2524 2: Refuse circuit creation for the DoSCircuitCreationDefenseTimePeriod period of time.
2526 "0" means use the consensus parameter. If not defined in the consensus, the value is 2.
2529 [[DoSCircuitCreationDefenseTimePeriod]] **DoSCircuitCreationDefenseTimePeriod** __N__ **seconds**|**minutes**|**hours**::
2531 The base time period in seconds that the DoS defense is activated for. The
2532 actual value is selected randomly for each activation from N+1 to 3/2 * N.
2533 "0" means use the consensus parameter. If not defined in the consensus,
2534 the value is 3600 seconds (1 hour).
2537 [[DoSConnectionEnabled]] **DoSConnectionEnabled** **0**|**1**|**auto**::
2539 Enable the connection DoS mitigation. If set to 1 (enabled), for client
2540 address only, this allows tor to mitigate against large number of
2541 concurrent connections made by a single IP address. "auto" means use the
2542 consensus parameter. If not defined in the consensus, the value is 0.
2545 [[DoSConnectionMaxConcurrentCount]] **DoSConnectionMaxConcurrentCount** __NUM__::
2547 The maximum threshold of concurrent connection from a client IP address.
2548 Above this limit, a defense selected by DoSConnectionDefenseType is
2549 applied. "0" means use the consensus parameter. If not defined in the
2550 consensus, the value is 100.
2553 [[DoSConnectionDefenseType]] **DoSConnectionDefenseType** __NUM__::
2555 This is the type of defense applied to a detected client address for the
2556 connection mitigation. The possible values are:
2560 2: Immediately close new connections.
2562 "0" means use the consensus parameter. If not defined in the consensus, the value is 2.
2565 [[DoSRefuseSingleHopClientRendezvous]] **DoSRefuseSingleHopClientRendezvous** **0**|**1**|**auto**::
2567 Refuse establishment of rendezvous points for single hop clients. In other
2568 words, if a client directly connects to the relay and sends an
2569 ESTABLISH_RENDEZVOUS cell, it is silently dropped. "auto" means use the
2570 consensus parameter. If not defined in the consensus, the value is 0.
2574 DIRECTORY AUTHORITY SERVER OPTIONS
2575 ----------------------------------
2577 The following options enable operation as a directory authority, and
2578 control how Tor behaves as a directory authority. You should not need
2579 to adjust any of them if you're running a regular relay or exit server
2580 on the public Tor network.
2582 [[AuthoritativeDirectory]] **AuthoritativeDirectory** **0**|**1**::
2583 When this option is set to 1, Tor operates as an authoritative directory
2584 server. Instead of caching the directory, it generates its own list of
2585 good servers, signs it, and sends that to the clients. Unless the clients
2586 already have you listed as a trusted directory, you probably do not want
2589 [[V3AuthoritativeDirectory]] **V3AuthoritativeDirectory** **0**|**1**::
2590 When this option is set in addition to **AuthoritativeDirectory**, Tor
2591 generates version 3 network statuses and serves descriptors, etc as
2592 described in dir-spec.txt file of https://spec.torproject.org/[torspec]
2593 (for Tor clients and servers running at least 0.2.0.x).
2595 [[VersioningAuthoritativeDirectory]] **VersioningAuthoritativeDirectory** **0**|**1**::
2596 When this option is set to 1, Tor adds information on which versions of
2597 Tor are still believed safe for use to the published directory. Each
2598 version 1 authority is automatically a versioning authority; version 2
2599 authorities provide this service optionally. See **RecommendedVersions**,
2600 **RecommendedClientVersions**, and **RecommendedServerVersions**.
2602 [[RecommendedVersions]] **RecommendedVersions** __STRING__::
2603 STRING is a comma-separated list of Tor versions currently believed to be
2604 safe. The list is included in each directory, and nodes which pull down the
2605 directory learn whether they need to upgrade. This option can appear
2606 multiple times: the values from multiple lines are spliced together. When
2607 this is set then **VersioningAuthoritativeDirectory** should be set too.
2609 [[RecommendedPackages]] **RecommendedPackages** __PACKAGENAME__ __VERSION__ __URL__ __DIGESTTYPE__**=**__DIGEST__ ::
2610 Adds "package" line to the directory authority's vote. This information
2611 is used to vote on the correct URL and digest for the released versions
2612 of different Tor-related packages, so that the consensus can certify
2613 them. This line may appear any number of times.
2615 [[RecommendedClientVersions]] **RecommendedClientVersions** __STRING__::
2616 STRING is a comma-separated list of Tor versions currently believed to be
2617 safe for clients to use. This information is included in version 2
2618 directories. If this is not set then the value of **RecommendedVersions**
2619 is used. When this is set then **VersioningAuthoritativeDirectory** should
2622 [[BridgeAuthoritativeDir]] **BridgeAuthoritativeDir** **0**|**1**::
2623 When this option is set in addition to **AuthoritativeDirectory**, Tor
2624 accepts and serves server descriptors, but it caches and serves the main
2625 networkstatus documents rather than generating its own. (Default: 0)
2627 [[MinUptimeHidServDirectoryV2]] **MinUptimeHidServDirectoryV2** __N__ **seconds**|**minutes**|**hours**|**days**|**weeks**::
2628 Minimum uptime of a v2 hidden service directory to be accepted as such by
2629 authoritative directories. (Default: 25 hours)
2631 [[RecommendedServerVersions]] **RecommendedServerVersions** __STRING__::
2632 STRING is a comma-separated list of Tor versions currently believed to be
2633 safe for servers to use. This information is included in version 2
2634 directories. If this is not set then the value of **RecommendedVersions**
2635 is used. When this is set then **VersioningAuthoritativeDirectory** should
2638 [[ConsensusParams]] **ConsensusParams** __STRING__::
2639 STRING is a space-separated list of key=value pairs that Tor will include
2640 in the "params" line of its networkstatus vote.
2642 [[DirAllowPrivateAddresses]] **DirAllowPrivateAddresses** **0**|**1**::
2643 If set to 1, Tor will accept server descriptors with arbitrary "Address"
2644 elements. Otherwise, if the address is not an IP address or is a private IP
2645 address, it will reject the server descriptor. Additionally, Tor
2646 will allow exit policies for private networks to fulfill Exit flag
2647 requirements. (Default: 0)
2649 [[AuthDirBadExit]] **AuthDirBadExit** __AddressPattern...__::
2650 Authoritative directories only. A set of address patterns for servers that
2651 will be listed as bad exits in any network status document this authority
2652 publishes, if **AuthDirListBadExits** is set. +
2654 (The address pattern syntax here and in the options below
2655 is the same as for exit policies, except that you don't need to say
2656 "accept" or "reject", and ports are not needed.)
2658 [[AuthDirInvalid]] **AuthDirInvalid** __AddressPattern...__::
2659 Authoritative directories only. A set of address patterns for servers that
2660 will never be listed as "valid" in any network status document that this
2661 authority publishes.
2663 [[AuthDirReject]] **AuthDirReject** __AddressPattern__...::
2664 Authoritative directories only. A set of address patterns for servers that
2665 will never be listed at all in any network status document that this
2666 authority publishes, or accepted as an OR address in any descriptor
2667 submitted for publication by this authority.
2669 [[AuthDirBadExitCCs]] **AuthDirBadExitCCs** __CC__,... +
2671 [[AuthDirInvalidCCs]] **AuthDirInvalidCCs** __CC__,... +
2673 [[AuthDirRejectCCs]] **AuthDirRejectCCs** __CC__,...::
2674 Authoritative directories only. These options contain a comma-separated
2675 list of country codes such that any server in one of those country codes
2676 will be marked as a bad exit/invalid for use, or rejected
2679 [[AuthDirListBadExits]] **AuthDirListBadExits** **0**|**1**::
2680 Authoritative directories only. If set to 1, this directory has some
2681 opinion about which nodes are unsuitable as exit nodes. (Do not set this to
2682 1 unless you plan to list non-functioning exits as bad; otherwise, you are
2683 effectively voting in favor of every declared exit as an exit.)
2685 [[AuthDirMaxServersPerAddr]] **AuthDirMaxServersPerAddr** __NUM__::
2686 Authoritative directories only. The maximum number of servers that we will
2687 list as acceptable on a single IP address. Set this to "0" for "no limit".
2690 [[AuthDirFastGuarantee]] **AuthDirFastGuarantee** __N__ **bytes**|**KBytes**|**MBytes**|**GBytes**|**TBytes**|**KBits**|**MBits**|**GBits**|**TBits**::
2691 Authoritative directories only. If non-zero, always vote the
2692 Fast flag for any relay advertising this amount of capacity or
2693 more. (Default: 100 KBytes)
2695 [[AuthDirGuardBWGuarantee]] **AuthDirGuardBWGuarantee** __N__ **bytes**|**KBytes**|**MBytes**|**GBytes**|**TBytes**|**KBits**|**MBits**|**GBits**|**TBits**::
2696 Authoritative directories only. If non-zero, this advertised capacity
2697 or more is always sufficient to satisfy the bandwidth requirement
2698 for the Guard flag. (Default: 2 MBytes)
2700 [[AuthDirPinKeys]] **AuthDirPinKeys** **0**|**1**::
2701 Authoritative directories only. If non-zero, do not allow any relay to
2702 publish a descriptor if any other relay has reserved its <Ed25519,RSA>
2703 identity keypair. In all cases, Tor records every keypair it accepts
2704 in a journal if it is new, or if it differs from the most recently
2705 accepted pinning for one of the keys it contains. (Default: 1)
2707 [[AuthDirSharedRandomness]] **AuthDirSharedRandomness** **0**|**1**::
2708 Authoritative directories only. Switch for the shared random protocol.
2709 If zero, the authority won't participate in the protocol. If non-zero
2710 (default), the flag "shared-rand-participate" is added to the authority
2711 vote indicating participation in the protocol. (Default: 1)
2713 [[AuthDirTestEd25519LinkKeys]] **AuthDirTestEd25519LinkKeys** **0**|**1**::
2714 Authoritative directories only. If this option is set to 0, then we treat
2715 relays as "Running" if their RSA key is correct when we probe them,
2716 regardless of their Ed25519 key. We should only ever set this option to 0
2717 if there is some major bug in Ed25519 link authentication that causes us
2718 to label all the relays as not Running. (Default: 1)
2720 [[BridgePassword]] **BridgePassword** __Password__::
2721 If set, contains an HTTP authenticator that tells a bridge authority to
2722 serve all requested bridge information. Used by the (only partially
2723 implemented) "bridge community" design, where a community of bridge
2724 relay operators all use an alternate bridge directory authority,
2725 and their target user audience can periodically fetch the list of
2726 available community bridges to stay up-to-date. (Default: not set)
2728 [[V3AuthVotingInterval]] **V3AuthVotingInterval** __N__ **minutes**|**hours**::
2729 V3 authoritative directories only. Configures the server's preferred voting
2730 interval. Note that voting will __actually__ happen at an interval chosen
2731 by consensus from all the authorities' preferred intervals. This time
2732 SHOULD divide evenly into a day. (Default: 1 hour)
2734 [[V3AuthVoteDelay]] **V3AuthVoteDelay** __N__ **minutes**|**hours**::
2735 V3 authoritative directories only. Configures the server's preferred delay
2736 between publishing its vote and assuming it has all the votes from all the
2737 other authorities. Note that the actual time used is not the server's
2738 preferred time, but the consensus of all preferences. (Default: 5 minutes)
2740 [[V3AuthDistDelay]] **V3AuthDistDelay** __N__ **minutes**|**hours**::
2741 V3 authoritative directories only. Configures the server's preferred delay
2742 between publishing its consensus and signature and assuming it has all the
2743 signatures from all the other authorities. Note that the actual time used
2744 is not the server's preferred time, but the consensus of all preferences.
2745 (Default: 5 minutes)
2747 [[V3AuthNIntervalsValid]] **V3AuthNIntervalsValid** __NUM__::
2748 V3 authoritative directories only. Configures the number of VotingIntervals
2749 for which each consensus should be valid for. Choosing high numbers
2750 increases network partitioning risks; choosing low numbers increases
2751 directory traffic. Note that the actual number of intervals used is not the
2752 server's preferred number, but the consensus of all preferences. Must be at
2753 least 2. (Default: 3)
2755 [[V3BandwidthsFile]] **V3BandwidthsFile** __FILENAME__::
2756 V3 authoritative directories only. Configures the location of the
2757 bandwidth-authority generated file storing information on relays' measured
2758 bandwidth capacities. To avoid inconsistent reads, bandwidth data should
2759 be written to temporary file, then renamed to the configured filename.
2762 [[V3AuthUseLegacyKey]] **V3AuthUseLegacyKey** **0**|**1**::
2763 If set, the directory authority will sign consensuses not only with its
2764 own signing key, but also with a "legacy" key and certificate with a
2765 different identity. This feature is used to migrate directory authority
2766 keys in the event of a compromise. (Default: 0)
2768 [[AuthDirHasIPv6Connectivity]] **AuthDirHasIPv6Connectivity** **0**|**1**::
2769 Authoritative directories only. When set to 0, OR ports with an
2770 IPv6 address are not included in the authority's votes. When set to 1,
2771 IPv6 OR ports are tested for reachability like IPv4 OR ports. If the
2772 reachability test succeeds, the authority votes for the IPv6 ORPort, and
2773 votes Running for the relay. If the reachability test fails, the authority
2774 does not vote for the IPv6 ORPort, and does not vote Running (Default: 0) +
2776 The content of the consensus depends on the number of voting authorities
2777 that set AuthDirHasIPv6Connectivity:
2779 If no authorities set AuthDirHasIPv6Connectivity 1, there will be no
2780 IPv6 ORPorts in the consensus.
2782 If a minority of authorities set AuthDirHasIPv6Connectivity 1,
2783 unreachable IPv6 ORPorts will be removed from the consensus. But the
2784 majority of IPv4-only authorities will still vote the relay as Running.
2785 Reachable IPv6 ORPort lines will be included in the consensus
2787 If a majority of voting authorities set AuthDirHasIPv6Connectivity 1,
2788 relays with unreachable IPv6 ORPorts will not be listed as Running.
2789 Reachable IPv6 ORPort lines will be included in the consensus
2790 (To ensure that any valid majority will vote relays with unreachable
2791 IPv6 ORPorts not Running, 75% of authorities must set
2792 AuthDirHasIPv6Connectivity 1.)
2794 [[MinMeasuredBWsForAuthToIgnoreAdvertised]] **MinMeasuredBWsForAuthToIgnoreAdvertised** __N__::
2795 A total value, in abstract bandwidth units, describing how much
2796 measured total bandwidth an authority should have observed on the network
2797 before it will treat advertised bandwidths as wholly
2798 unreliable. (Default: 500)
2800 HIDDEN SERVICE OPTIONS
2801 ----------------------
2803 The following options are used to configure a hidden service.
2805 [[HiddenServiceDir]] **HiddenServiceDir** __DIRECTORY__::
2806 Store data files for a hidden service in DIRECTORY. Every hidden service
2807 must have a separate directory. You may use this option multiple times to
2808 specify multiple services. If DIRECTORY does not exist, Tor will create it.
2809 (Note: in current versions of Tor, if DIRECTORY is a relative path,
2810 it will be relative to the current
2811 working directory of Tor instance, not to its DataDirectory. Do not
2812 rely on this behavior; it is not guaranteed to remain the same in future
2815 [[HiddenServicePort]] **HiddenServicePort** __VIRTPORT__ [__TARGET__]::
2816 Configure a virtual port VIRTPORT for a hidden service. You may use this
2817 option multiple times; each time applies to the service using the most
2818 recent HiddenServiceDir. By default, this option maps the virtual port to
2819 the same port on 127.0.0.1 over TCP. You may override the target port,
2820 address, or both by specifying a target of addr, port, addr:port, or
2821 **unix:**__path__. (You can specify an IPv6 target as [addr]:port. Unix
2822 paths may be quoted, and may use standard C escapes.)
2823 You may also have multiple lines with the same VIRTPORT: when a user
2824 connects to that VIRTPORT, one of the TARGETs from those lines will be
2825 chosen at random. Note that address-port pairs have to be comma-separated.
2827 [[PublishHidServDescriptors]] **PublishHidServDescriptors** **0**|**1**::
2828 If set to 0, Tor will run any hidden services you configure, but it won't
2829 advertise them to the rendezvous directory. This option is only useful if
2830 you're using a Tor controller that handles hidserv publishing for you.
2833 [[HiddenServiceVersion]] **HiddenServiceVersion** **2**|**3**::
2834 A list of rendezvous service descriptor versions to publish for the hidden
2835 service. Currently, versions 2 and 3 are supported. (Default: 3)
2837 [[HiddenServiceAuthorizeClient]] **HiddenServiceAuthorizeClient** __auth-type__ __client-name__,__client-name__,__...__::
2838 If configured, the hidden service is accessible for authorized clients
2839 only. The auth-type can either be \'basic' for a general-purpose
2840 authorization protocol or \'stealth' for a less scalable protocol that also
2841 hides service activity from unauthorized clients. Only clients that are
2842 listed here are authorized to access the hidden service. Valid client names
2843 are 1 to 16 characters long and only use characters in A-Za-z0-9+-_ (no
2844 spaces). If this option is set, the hidden service is not accessible for
2845 clients without authorization any more. Generated authorization data can be
2846 found in the hostname file. Clients need to put this authorization data in
2847 their configuration file using **HidServAuth**. This option is only for v2
2848 services; v3 services configure client authentication in a subdirectory of
2849 HiddenServiceDir instead (see the **Client Authorization** section).
2851 [[HiddenServiceAllowUnknownPorts]] **HiddenServiceAllowUnknownPorts** **0**|**1**::
2852 If set to 1, then connections to unrecognized ports do not cause the
2853 current hidden service to close rendezvous circuits. (Setting this to 0 is
2854 not an authorization mechanism; it is instead meant to be a mild
2855 inconvenience to port-scanners.) (Default: 0)
2857 [[HiddenServiceExportCircuitID]] **HiddenServiceExportCircuitID** __protocol__::
2858 The onion service will use the given protocol to expose the global circuit
2859 identifier of each inbound client circuit via the selected protocol. The only
2860 protocol supported right now \'haproxy'. This option is only for v3
2861 services. (Default: none) +
2863 The haproxy option works in the following way: when the feature is
2864 enabled, the Tor process will write a header line when a client is connecting
2865 to the onion service. The header will look like this: +
2867 "PROXY TCP6 fc00:dead:beef:4dad::ffff:ffff ::1 65535 42\r\n" +
2869 We encode the "global circuit identifier" as the last 32-bits of the first
2870 IPv6 address. All other values in the header can safely be ignored. You can
2871 compute the global circuit identifier using the following formula given the
2872 IPv6 address "fc00:dead:beef:4dad::AABB:CCDD": +
2874 global_circuit_id = (0xAA << 24) + (0xBB << 16) + (0xCC << 8) + 0xDD; +
2876 In the case above, where the last 32-bit is 0xffffffff, the global circuit
2877 identifier would be 4294967295. You can use this value together with Tor's
2878 control port where it is possible to terminate a circuit given the global
2879 circuit identifier. For more information about this see controls-spec.txt. +
2881 The HAProxy version 1 proxy protocol is described in detail at
2882 https://www.haproxy.org/download/1.8/doc/proxy-protocol.txt
2884 [[HiddenServiceMaxStreams]] **HiddenServiceMaxStreams** __N__::
2885 The maximum number of simultaneous streams (connections) per rendezvous
2886 circuit. The maximum value allowed is 65535. (Setting this to 0 will allow
2887 an unlimited number of simultaneous streams.) (Default: 0)
2889 [[HiddenServiceMaxStreamsCloseCircuit]] **HiddenServiceMaxStreamsCloseCircuit** **0**|**1**::
2890 If set to 1, then exceeding **HiddenServiceMaxStreams** will cause the
2891 offending rendezvous circuit to be torn down, as opposed to stream creation
2892 requests that exceed the limit being silently ignored. (Default: 0)
2894 [[RendPostPeriod]] **RendPostPeriod** __N__ **seconds**|**minutes**|**hours**|**days**|**weeks**::
2895 Every time the specified period elapses, Tor uploads any rendezvous
2896 service descriptors to the directory servers. This information is also
2897 uploaded whenever it changes. Minimum value allowed is 10 minutes and
2898 maximum is 3.5 days. This option is only for v2 services.
2901 [[HiddenServiceDirGroupReadable]] **HiddenServiceDirGroupReadable** **0**|**1**::
2902 If this option is set to 1, allow the filesystem group to read the
2903 hidden service directory and hostname file. If the option is set to 0,
2904 only owner is able to read the hidden service directory. (Default: 0)
2905 Has no effect on Windows.
2907 [[HiddenServiceNumIntroductionPoints]] **HiddenServiceNumIntroductionPoints** __NUM__::
2908 Number of introduction points the hidden service will have. You can't
2909 have more than 10 for v2 service and 20 for v3. (Default: 3)
2911 [[HiddenServiceSingleHopMode]] **HiddenServiceSingleHopMode** **0**|**1**::
2912 **Experimental - Non Anonymous** Hidden Services on a tor instance in
2913 HiddenServiceSingleHopMode make one-hop (direct) circuits between the onion
2914 service server, and the introduction and rendezvous points. (Onion service
2915 descriptors are still posted using 3-hop paths, to avoid onion service
2916 directories blocking the service.)
2917 This option makes every hidden service instance hosted by a tor instance a
2918 Single Onion Service. One-hop circuits make Single Onion servers easily
2919 locatable, but clients remain location-anonymous. However, the fact that a
2920 client is accessing a Single Onion rather than a Hidden Service may be
2921 statistically distinguishable. +
2923 **WARNING:** Once a hidden service directory has been used by a tor
2924 instance in HiddenServiceSingleHopMode, it can **NEVER** be used again for
2925 a hidden service. It is best practice to create a new hidden service
2926 directory, key, and address for each new Single Onion Service and Hidden
2927 Service. It is not possible to run Single Onion Services and Hidden
2928 Services from the same tor instance: they should be run on different
2929 servers with different IP addresses. +
2931 HiddenServiceSingleHopMode requires HiddenServiceNonAnonymousMode to be set
2932 to 1. Since a Single Onion service is non-anonymous, you can not configure
2933 a SOCKSPort on a tor instance that is running in
2934 **HiddenServiceSingleHopMode**. Can not be changed while tor is running.
2937 [[HiddenServiceNonAnonymousMode]] **HiddenServiceNonAnonymousMode** **0**|**1**::
2938 Makes hidden services non-anonymous on this tor instance. Allows the
2939 non-anonymous HiddenServiceSingleHopMode. Enables direct connections in the
2940 server-side hidden service protocol. If you are using this option,
2941 you need to disable all client-side services on your Tor instance,
2942 including setting SOCKSPort to "0". Can not be changed while tor is
2943 running. (Default: 0)
2945 Client Authorization
2946 --------------------
2950 To configure client authorization on the service side, the
2951 "<HiddenServiceDir>/authorized_clients/" directory needs to exist. Each file
2952 in that directory should be suffixed with ".auth" (i.e. "alice.auth"; the
2953 file name is irrelevant) and its content format MUST be:
2955 <auth-type>:<key-type>:<base32-encoded-public-key>
2957 The supported <auth-type> are: "descriptor". The supported <key-type> are:
2958 "x25519". The <base32-encoded-public-key> is the base32 representation of
2959 the raw key bytes only (32 bytes for x25519).
2961 Each file MUST contain one line only. Any malformed file will be
2962 ignored. Client authorization will only be enabled for the service if tor
2963 successfully loads at least one authorization file.
2965 Note that once you've configured client authorization, anyone else with the
2966 address won't be able to access it from this point on. If no authorization is
2967 configured, the service will be accessible to anyone with the onion address.
2969 Revoking a client can be done by removing their ".auth" file, however the
2970 revocation will be in effect only after the tor process gets restarted even if
2971 a SIGHUP takes place.
2973 See the Appendix G in the rend-spec-v3.txt file of
2974 https://spec.torproject.org/[torspec] for more information.
2976 TESTING NETWORK OPTIONS
2977 -----------------------
2979 The following options are used for running a testing Tor network.
2981 [[TestingTorNetwork]] **TestingTorNetwork** **0**|**1**::
2982 If set to 1, Tor adjusts default values of the configuration options below,
2983 so that it is easier to set up a testing Tor network. May only be set if
2984 non-default set of DirAuthorities is set. Cannot be unset while Tor is
2988 ServerDNSAllowBrokenConfig 1
2989 DirAllowPrivateAddresses 1
2990 EnforceDistinctSubnets 0
2992 AuthDirMaxServersPerAddr 0
2993 AuthDirMaxServersPerAuthAddr 0
2994 ClientBootstrapConsensusAuthorityDownloadInitialDelay 0
2995 ClientBootstrapConsensusFallbackDownloadInitialDelay 0
2996 ClientBootstrapConsensusAuthorityOnlyDownloadInitialDelay 0
2997 ClientDNSRejectInternalAddresses 0
2998 ClientRejectInternalAddresses 0
2999 CountPrivateBandwidth 1
3000 ExitPolicyRejectPrivate 0
3001 ExtendAllowPrivateAddresses 1
3002 V3AuthVotingInterval 5 minutes
3003 V3AuthVoteDelay 20 seconds
3004 V3AuthDistDelay 20 seconds
3005 MinUptimeHidServDirectoryV2 0 seconds
3006 TestingV3AuthInitialVotingInterval 5 minutes
3007 TestingV3AuthInitialVoteDelay 20 seconds
3008 TestingV3AuthInitialDistDelay 20 seconds
3009 TestingAuthDirTimeToLearnReachability 0 minutes
3010 TestingEstimatedDescriptorPropagationTime 0 minutes
3011 TestingServerDownloadInitialDelay 0
3012 TestingClientDownloadInitialDelay 0
3013 TestingServerConsensusDownloadInitialDelay 0
3014 TestingClientConsensusDownloadInitialDelay 0
3015 TestingBridgeDownloadInitialDelay 10
3016 TestingBridgeBootstrapDownloadInitialDelay 0
3017 TestingClientMaxIntervalWithoutRequest 5 seconds
3018 TestingDirConnectionMaxStall 30 seconds
3019 TestingEnableConnBwEvent 1
3020 TestingEnableCellStatsEvent 1
3022 [[TestingV3AuthInitialVotingInterval]] **TestingV3AuthInitialVotingInterval** __N__ **minutes**|**hours**::
3023 Like V3AuthVotingInterval, but for initial voting interval before the first
3024 consensus has been created. Changing this requires that
3025 **TestingTorNetwork** is set. (Default: 30 minutes)
3027 [[TestingV3AuthInitialVoteDelay]] **TestingV3AuthInitialVoteDelay** __N__ **minutes**|**hours**::
3028 Like V3AuthVoteDelay, but for initial voting interval before
3029 the first consensus has been created. Changing this requires that
3030 **TestingTorNetwork** is set. (Default: 5 minutes)
3032 [[TestingV3AuthInitialDistDelay]] **TestingV3AuthInitialDistDelay** __N__ **minutes**|**hours**::
3033 Like V3AuthDistDelay, but for initial voting interval before
3034 the first consensus has been created. Changing this requires that
3035 **TestingTorNetwork** is set. (Default: 5 minutes)
3037 [[TestingV3AuthVotingStartOffset]] **TestingV3AuthVotingStartOffset** __N__ **seconds**|**minutes**|**hours**::
3038 Directory authorities offset voting start time by this much.
3039 Changing this requires that **TestingTorNetwork** is set. (Default: 0)
3041 [[TestingAuthDirTimeToLearnReachability]] **TestingAuthDirTimeToLearnReachability** __N__ **minutes**|**hours**::
3042 After starting as an authority, do not make claims about whether routers
3043 are Running until this much time has passed. Changing this requires
3044 that **TestingTorNetwork** is set. (Default: 30 minutes)
3046 [[TestingEstimatedDescriptorPropagationTime]] **TestingEstimatedDescriptorPropagationTime** __N__ **minutes**|**hours**::
3047 Clients try downloading server descriptors from directory caches after this
3048 time. Changing this requires that **TestingTorNetwork** is set. (Default:
3051 [[TestingMinFastFlagThreshold]] **TestingMinFastFlagThreshold** __N__ **bytes**|**KBytes**|**MBytes**|**GBytes**|**TBytes**|**KBits**|**MBits**|**GBits**|**TBits**::
3052 Minimum value for the Fast flag. Overrides the ordinary minimum taken
3053 from the consensus when TestingTorNetwork is set. (Default: 0.)
3055 [[TestingServerDownloadInitialDelay]] **TestingServerDownloadInitialDelay** __N__::
3056 Initial delay in seconds for when servers should download things in general. Changing this
3057 requires that **TestingTorNetwork** is set. (Default: 0)
3059 [[TestingClientDownloadInitialDelay]] **TestingClientDownloadInitialDelay** __N__::
3060 Initial delay in seconds for when clients should download things in general. Changing this
3061 requires that **TestingTorNetwork** is set. (Default: 0)
3063 [[TestingServerConsensusDownloadInitialDelay]] **TestingServerConsensusDownloadInitialDelay** __N__::
3064 Initial delay in seconds for when servers should download consensuses. Changing this
3065 requires that **TestingTorNetwork** is set. (Default: 0)
3067 [[TestingClientConsensusDownloadInitialDelay]] **TestingClientConsensusDownloadInitialDelay** __N__::
3068 Initial delay in seconds for when clients should download consensuses. Changing this
3069 requires that **TestingTorNetwork** is set. (Default: 0)
3071 [[TestingBridgeDownloadInitialDelay]] **TestingBridgeDownloadInitialDelay** __N__::
3072 Initial delay in seconds for when clients should download each bridge descriptor when they
3073 know that one or more of their configured bridges are running. Changing
3074 this requires that **TestingTorNetwork** is set. (Default: 10800)
3076 [[TestingBridgeBootstrapDownloadInitialDelay]] **TestingBridgeBootstrapDownloadInitialDelay** __N__::
3077 Initial delay in seconds for when clients should download each bridge descriptor when they
3078 have just started, or when they can not contact any of their bridges.
3079 Changing this requires that **TestingTorNetwork** is set. (Default: 0)
3081 [[TestingClientMaxIntervalWithoutRequest]] **TestingClientMaxIntervalWithoutRequest** __N__ **seconds**|**minutes**::
3082 When directory clients have only a few descriptors to request, they batch
3083 them until they have more, or until this amount of time has passed.
3084 Changing this requires that **TestingTorNetwork** is set. (Default: 10
3087 [[TestingDirConnectionMaxStall]] **TestingDirConnectionMaxStall** __N__ **seconds**|**minutes**::
3088 Let a directory connection stall this long before expiring it.
3089 Changing this requires that **TestingTorNetwork** is set. (Default:
3092 [[TestingDirAuthVoteExit]] **TestingDirAuthVoteExit** __node__,__node__,__...__::
3093 A list of identity fingerprints, country codes, and
3094 address patterns of nodes to vote Exit for regardless of their
3095 uptime, bandwidth, or exit policy. See the **ExcludeNodes**
3096 option for more information on how to specify nodes. +
3098 In order for this option to have any effect, **TestingTorNetwork**
3099 has to be set. See the **ExcludeNodes** option for more
3100 information on how to specify nodes.
3102 [[TestingDirAuthVoteExitIsStrict]] **TestingDirAuthVoteExitIsStrict** **0**|**1** ::
3103 If True (1), a node will never receive the Exit flag unless it is specified
3104 in the **TestingDirAuthVoteExit** list, regardless of its uptime, bandwidth,
3107 In order for this option to have any effect, **TestingTorNetwork**
3110 [[TestingDirAuthVoteGuard]] **TestingDirAuthVoteGuard** __node__,__node__,__...__::
3111 A list of identity fingerprints and country codes and
3112 address patterns of nodes to vote Guard for regardless of their
3113 uptime and bandwidth. See the **ExcludeNodes** option for more
3114 information on how to specify nodes. +
3116 In order for this option to have any effect, **TestingTorNetwork**
3119 [[TestingDirAuthVoteGuardIsStrict]] **TestingDirAuthVoteGuardIsStrict** **0**|**1** ::
3120 If True (1), a node will never receive the Guard flag unless it is specified
3121 in the **TestingDirAuthVoteGuard** list, regardless of its uptime and bandwidth. +
3123 In order for this option to have any effect, **TestingTorNetwork**
3126 [[TestingDirAuthVoteHSDir]] **TestingDirAuthVoteHSDir** __node__,__node__,__...__::
3127 A list of identity fingerprints and country codes and
3128 address patterns of nodes to vote HSDir for regardless of their
3129 uptime and DirPort. See the **ExcludeNodes** option for more
3130 information on how to specify nodes. +
3132 In order for this option to have any effect, **TestingTorNetwork**
3135 [[TestingDirAuthVoteHSDirIsStrict]] **TestingDirAuthVoteHSDirIsStrict** **0**|**1** ::
3136 If True (1), a node will never receive the HSDir flag unless it is specified
3137 in the **TestingDirAuthVoteHSDir** list, regardless of its uptime and DirPort. +
3139 In order for this option to have any effect, **TestingTorNetwork**
3142 [[TestingEnableConnBwEvent]] **TestingEnableConnBwEvent** **0**|**1**::
3143 If this option is set, then Tor controllers may register for CONN_BW
3144 events. Changing this requires that **TestingTorNetwork** is set.
3147 [[TestingEnableCellStatsEvent]] **TestingEnableCellStatsEvent** **0**|**1**::
3148 If this option is set, then Tor controllers may register for CELL_STATS
3149 events. Changing this requires that **TestingTorNetwork** is set.
3152 [[TestingMinExitFlagThreshold]] **TestingMinExitFlagThreshold** __N__ **KBytes**|**MBytes**|**GBytes**|**TBytes**|**KBits**|**MBits**|**GBits**|**TBits**::
3153 Sets a lower-bound for assigning an exit flag when running as an
3154 authority on a testing network. Overrides the usual default lower bound
3155 of 4 KB. (Default: 0)
3157 [[TestingLinkCertLifetime]] **TestingLinkCertLifetime** __N__ **seconds**|**minutes**|**hours**|**days**|**weeks**|**months**::
3158 Overrides the default lifetime for the certificates used to authenticate
3159 our X509 link cert with our ed25519 signing key.
3162 [[TestingAuthKeyLifetime]] **TestingAuthKeyLifetime** __N__ **seconds**|**minutes**|**hours**|**days**|**weeks**|**months**::
3163 Overrides the default lifetime for a signing Ed25519 TLS Link authentication
3167 [[TestingLinkKeySlop]] **TestingLinkKeySlop** __N__ **seconds**|**minutes**|**hours** +
3169 [[TestingAuthKeySlop]] **TestingAuthKeySlop** __N__ **seconds**|**minutes**|**hours** +
3171 [[TestingSigningKeySlop]] **TestingSigningKeySlop** __N__ **seconds**|**minutes**|**hours**::
3172 How early before the official expiration of a an Ed25519 signing key do
3173 we replace it and issue a new key?
3174 (Default: 3 hours for link and auth; 1 day for signing.)
3176 NON-PERSISTENT OPTIONS
3177 ----------------------
3179 These options are not saved to the torrc file by the "SAVECONF" controller
3180 command. Other options of this type are documented in control-spec.txt,
3181 section 5.4. End-users should mostly ignore them.
3183 [[UnderscorePorts]] **\_\_ControlPort**, **\_\_DirPort**, **\_\_DNSPort**, **\_\_ExtORPort**, **\_\_NATDPort**, **\_\_ORPort**, **\_\_SocksPort**, **\_\_TransPort**::
3184 These underscore-prefixed options are variants of the regular Port
3185 options. They behave the same, except they are not saved to the
3186 torrc file by the controller's SAVECONF command.
3192 Tor catches the following signals:
3194 [[SIGTERM]] **SIGTERM**::
3195 Tor will catch this, clean up and sync to disk if necessary, and exit.
3197 [[SIGINT]] **SIGINT**::
3198 Tor clients behave as with SIGTERM; but Tor servers will do a controlled
3199 slow shutdown, closing listeners and waiting 30 seconds before exiting.
3200 (The delay can be configured with the ShutdownWaitLength config option.)
3202 [[SIGHUP]] **SIGHUP**::
3203 The signal instructs Tor to reload its configuration (including closing and
3204 reopening logs), and kill and restart its helper processes if applicable.
3206 [[SIGUSR1]] **SIGUSR1**::
3207 Log statistics about current connections, past connections, and throughput.
3209 [[SIGUSR2]] **SIGUSR2**::
3210 Switch all logs to loglevel debug. You can go back to the old loglevels by
3213 [[SIGCHLD]] **SIGCHLD**::
3214 Tor receives this signal when one of its helper processes has exited, so it
3217 [[SIGPIPE]] **SIGPIPE**::
3218 Tor catches this signal and ignores it.
3220 [[SIGXFSZ]] **SIGXFSZ**::
3221 If this signal exists on your platform, Tor catches and ignores it.
3226 **@CONFDIR@/torrc**::
3227 The configuration file, which contains "option value" pairs.
3230 Fallback location for torrc, if @CONFDIR@/torrc is not found.
3232 **@LOCALSTATEDIR@/lib/tor/**::
3233 The tor process stores keys and other data here.
3236 __CacheDirectory__**/cached-certs**::
3237 This file holds downloaded directory key certificates that are used to
3238 verify authenticity of documents generated by Tor directory authorities.
3240 __CacheDirectory__**/cached-consensus** and/or **cached-microdesc-consensus**::
3241 The most recent consensus network status document we've downloaded.
3243 __CacheDirectory__**/cached-descriptors** and **cached-descriptors.new**::
3244 These files hold downloaded router statuses. Some routers may appear more
3245 than once; if so, the most recently published descriptor is used. Lines
3246 beginning with @-signs are annotations that contain more information about
3247 a given router. The ".new" file is an append-only journal; when it gets
3248 too large, all entries are merged into a new cached-descriptors file.
3250 __CacheDirectory__**/cached-extrainfo** and **cached-extrainfo.new**::
3251 As "cached-descriptors", but holds optionally-downloaded "extra-info"
3252 documents. Relays use these documents to send inessential information
3253 about statistics, bandwidth history, and network health to the
3254 authorities. They aren't fetched by default; see the DownloadExtraInfo
3255 option for more info.
3257 __CacheDirectory__**/cached-microdescs** and **cached-microdescs.new**::
3258 These files hold downloaded microdescriptors. Lines beginning with
3259 @-signs are annotations that contain more information about a given
3260 router. The ".new" file is an append-only journal; when it gets too
3261 large, all entries are merged into a new cached-microdescs file.
3263 __CacheDirectory__**/cached-routers** and **cached-routers.new**::
3264 Obsolete versions of cached-descriptors and cached-descriptors.new. When
3265 Tor can't find the newer files, it looks here instead.
3267 __DataDirectory__**/state**::
3268 A set of persistent key-value mappings. These are documented in
3269 the file. These include:
3270 - The current entry guards and their status.
3271 - The current bandwidth accounting values.
3272 - When the file was last written
3273 - What version of Tor generated the state file
3274 - A short history of bandwidth usage, as produced in the server
3277 __DataDirectory__**/sr-state**::
3278 Authority only. State file used to record information about the current
3279 status of the shared-random-value voting state.
3281 __CacheDirectory__**/diff-cache**::
3282 Directory cache only. Holds older consensuses, and diffs from older
3283 consensuses to the most recent consensus of each type, compressed
3284 in various ways. Each file contains a set of key-value arguments
3285 describing its contents, followed by a single NUL byte, followed by the
3288 __DataDirectory__**/bw_accounting**::
3289 Used to track bandwidth accounting values (when the current period starts
3290 and ends; how much has been read and written so far this period). This file
3291 is obsolete, and the data is now stored in the \'state' file instead.
3293 __DataDirectory__**/control_auth_cookie**::
3294 Used for cookie authentication with the controller. Location can be
3295 overridden by the CookieAuthFile config option. Regenerated on startup. See
3296 control-spec.txt in https://spec.torproject.org/[torspec] for details.
3297 Only used when cookie authentication is enabled.
3299 __DataDirectory__**/lock**::
3300 This file is used to prevent two Tor instances from using same data
3301 directory. If access to this file is locked, data directory is already
3304 __DataDirectory__**/key-pinning-journal**::
3305 Used by authorities. A line-based file that records mappings between
3306 RSA1024 identity keys and Ed25519 identity keys. Authorities enforce
3307 these mappings, so that once a relay has picked an Ed25519 key, stealing
3308 or factoring the RSA1024 key will no longer let an attacker impersonate
3311 __KeyDirectory__**/authority_identity_key**::
3312 A v3 directory authority's master identity key, used to authenticate its
3313 signing key. Tor doesn't use this while it's running. The tor-gencert
3314 program uses this. If you're running an authority, you should keep this
3315 key offline, and not actually put it here.
3317 __KeyDirectory__**/authority_certificate**::
3318 A v3 directory authority's certificate, which authenticates the authority's
3319 current vote- and consensus-signing key using its master identity key.
3320 Only directory authorities use this file.
3322 __KeyDirectory__**/authority_signing_key**::
3323 A v3 directory authority's signing key, used to sign votes and consensuses.
3324 Only directory authorities use this file. Corresponds to the
3325 **authority_certificate** cert.
3327 __KeyDirectory__**/legacy_certificate**::
3328 As authority_certificate: used only when V3AuthUseLegacyKey is set.
3329 See documentation for V3AuthUseLegacyKey.
3331 __KeyDirectory__**/legacy_signing_key**::
3332 As authority_signing_key: used only when V3AuthUseLegacyKey is set.
3333 See documentation for V3AuthUseLegacyKey.
3335 __KeyDirectory__**/secret_id_key**::
3336 A relay's RSA1024 permanent identity key, including private and public
3337 components. Used to sign router descriptors, and to sign other keys.
3339 __KeyDirectory__**/ed25519_master_id_public_key**::
3340 The public part of a relay's Ed25519 permanent identity key.
3342 __KeyDirectory__**/ed25519_master_id_secret_key**::
3343 The private part of a relay's Ed25519 permanent identity key. This key
3344 is used to sign the medium-term ed25519 signing key. This file can be
3345 kept offline, or kept encrypted. If so, Tor will not be able to generate
3346 new signing keys itself; you'll need to use tor --keygen yourself to do
3349 __KeyDirectory__**/ed25519_signing_secret_key**::
3350 The private and public components of a relay's medium-term Ed25519 signing
3351 key. This key is authenticated by the Ed25519 master key, in turn
3352 authenticates other keys (and router descriptors).
3354 __KeyDirectory__**/ed25519_signing_cert**::
3355 The certificate which authenticates "ed25519_signing_secret_key" as
3356 having been signed by the Ed25519 master key.
3358 __KeyDirectory__**/secret_onion_key** and **secret_onion_key.old**::
3359 A relay's RSA1024 short-term onion key. Used to decrypt old-style ("TAP")
3360 circuit extension requests. The ".old" file holds the previously
3361 generated key, which the relay uses to handle any requests that were
3362 made by clients that didn't have the new one.
3364 __KeyDirectory__**/secret_onion_key_ntor** and **secret_onion_key_ntor.old**::
3365 A relay's Curve25519 short-term onion key. Used to handle modern ("ntor")
3366 circuit extension requests. The ".old" file holds the previously
3367 generated key, which the relay uses to handle any requests that were
3368 made by clients that didn't have the new one.
3370 __DataDirectory__**/fingerprint**::
3371 Only used by servers. Holds the fingerprint of the server's identity key.
3373 __DataDirectory__**/hashed-fingerprint**::
3374 Only used by bridges. Holds the hashed fingerprint of the bridge's
3375 identity key. (That is, the hash of the hash of the identity key.)
3377 __DataDirectory__**/approved-routers**::
3378 Only used by authoritative directory servers. This file lists
3379 the status of routers by their identity fingerprint.
3380 Each line lists a status and a fingerprint separated by
3381 whitespace. See your **fingerprint** file in the __DataDirectory__ for an
3382 example line. If the status is **!reject** then descriptors from the
3383 given identity (fingerprint) are rejected by this server. If it is
3384 **!invalid** then descriptors are accepted but marked in the directory as
3385 not valid, that is, not recommended.
3387 __DataDirectory__**/v3-status-votes**::
3388 Only for v3 authoritative directory servers. This file contains
3389 status votes from all the authoritative directory servers.
3391 __CacheDirectory__**/unverified-consensus**::
3392 This file contains a network consensus document that has been downloaded,
3393 but which we didn't have the right certificates to check yet.
3395 __CacheDirectory__**/unverified-microdesc-consensus**::
3396 This file contains a microdescriptor-flavored network consensus document
3397 that has been downloaded, but which we didn't have the right certificates
3400 __DataDirectory__**/unparseable-desc**::
3401 Onion server descriptors that Tor was unable to parse are dumped to this
3402 file. Only used for debugging.
3404 __DataDirectory__**/router-stability**::
3405 Only used by authoritative directory servers. Tracks measurements for
3406 router mean-time-between-failures so that authorities have a good idea of
3407 how to set their Stable flags.
3409 __DataDirectory__**/stats/dirreq-stats**::
3410 Only used by directory caches and authorities. This file is used to
3411 collect directory request statistics.
3413 __DataDirectory__**/stats/entry-stats**::
3414 Only used by servers. This file is used to collect incoming connection
3415 statistics by Tor entry nodes.
3417 __DataDirectory__**/stats/bridge-stats**::
3418 Only used by servers. This file is used to collect incoming connection
3419 statistics by Tor bridges.
3421 __DataDirectory__**/stats/exit-stats**::
3422 Only used by servers. This file is used to collect outgoing connection
3423 statistics by Tor exit routers.
3425 __DataDirectory__**/stats/buffer-stats**::
3426 Only used by servers. This file is used to collect buffer usage
3429 __DataDirectory__**/stats/conn-stats**::
3430 Only used by servers. This file is used to collect approximate connection
3431 history (number of active connections over time).
3433 __DataDirectory__**/stats/hidserv-stats**::
3434 Only used by servers. This file is used to collect approximate counts
3435 of what fraction of the traffic is hidden service rendezvous traffic, and
3436 approximately how many hidden services the relay has seen.
3438 __DataDirectory__**/networkstatus-bridges**::
3439 Only used by authoritative bridge directories. Contains information
3440 about bridges that have self-reported themselves to the bridge
3443 __DataDirectory__**/approved-routers**::
3444 Authorities only. This file is used to configure which relays are
3445 known to be valid, invalid, and so forth.
3447 __HiddenServiceDirectory__**/hostname**::
3448 The <base32-encoded-fingerprint>.onion domain name for this hidden service.
3449 If the hidden service is restricted to authorized clients only, this file
3450 also contains authorization data for all clients.
3452 Note that clients will ignore any extra subdomains prepended to a hidden
3453 service hostname. So if you have "xyz.onion" as your hostname, you
3454 can tell clients to connect to "www.xyz.onion" or "irc.xyz.onion"
3455 for virtual-hosting purposes.
3457 __HiddenServiceDirectory__**/private_key**::
3458 The private key for this hidden service.
3460 __HiddenServiceDirectory__**/client_keys**::
3461 Authorization data for a hidden service that is only accessible by
3464 __HiddenServiceDirectory__**/onion_service_non_anonymous**::
3465 This file is present if a hidden service key was created in
3466 **HiddenServiceNonAnonymousMode**.
3470 **torsocks**(1), **torify**(1) +
3472 **https://www.torproject.org/**
3474 **torspec: https://spec.torproject.org **
3479 Plenty, probably. Tor is still in development. Please report them at https://trac.torproject.org/.
3483 Roger Dingledine [arma at mit.edu], Nick Mathewson [nickm at alum.mit.edu].