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-version]] **--version**::
92 Display Tor version and exit.
94 [[opt-quiet]] **--quiet**|**--hush**::
95 Override the default console log. By default, Tor starts out logging
96 messages at level "notice" and higher to the console. It stops doing so
97 after it parses its configuration, if the configuration tells it to log
98 anywhere else. You can override this behavior with the **--hush** option,
99 which tells Tor to only send warnings and errors to the console, or with
100 the **--quiet** option, which tells Tor not to log to the console at all.
102 [[opt-keygen]] **--keygen** [**--newpass**]::
103 Running "tor --keygen" creates a new ed25519 master identity key for a
104 relay, or only a fresh temporary signing key and certificate, if you
105 already have a master key. Optionally you can encrypt the master identity
106 key with a passphrase: Tor will ask you for one. If you don't want to
107 encrypt the master key, just don't enter any passphrase when asked. +
109 The **--newpass** option should be used with --keygen only when you need
110 to add, change, or remove a passphrase on an existing ed25519 master
111 identity key. You will be prompted for the old passphase (if any),
112 and the new passphrase (if any). +
114 When generating a master key, you will probably want to use
115 **--DataDirectory** to control where the keys
116 and certificates will be stored, and **--SigningKeyLifetime** to
117 control their lifetimes. Their behavior is as documented in the
118 server options section below. (You must have write access to the specified
121 To use the generated files, you must copy them to the DataDirectory/keys
122 directory of your Tor daemon, and make sure that they are owned by the
123 user actually running the Tor daemon on your system.
125 **--passphrase-fd** __FILEDES__::
126 Filedescriptor to read the passphrase from. Note that unlike with the
127 tor-gencert program, the entire file contents are read and used as
128 the passphrase, including any trailing newlines.
129 Default: read from the terminal.
131 [[opt-key-expiration]] **--key-expiration** [**purpose**]::
132 The **purpose** specifies which type of key certificate to determine
133 the expiration of. The only currently recognised **purpose** is
136 Running "tor --key-expiration sign" will attempt to find your signing
137 key certificate and will output, both in the logs as well as to stdout,
138 the signing key certificate's expiration time in ISO-8601 format.
139 For example, the output sent to stdout will be of the form:
140 "signing-cert-expiry: 2017-07-25 08:30:15 UTC"
142 Other options can be specified on the command-line in the format "--option
143 value", in the format "option value", or in a configuration file. For
144 instance, you can tell Tor to start listening for SOCKS connections on port
145 9999 by passing --SocksPort 9999 or SocksPort 9999 to it on the command line,
146 or by putting "SocksPort 9999" in the configuration file. You will need to
147 quote options with spaces in them: if you want Tor to log all debugging
148 messages to debug.log, you will probably need to say --Log 'debug file
151 Options on the command line override those in configuration files. See the
152 next section for more information.
154 THE CONFIGURATION FILE FORMAT
155 -----------------------------
157 All configuration options in a configuration are written on a single line by
158 default. They take the form of an option name and a value, or an option name
159 and a quoted value (option value or option "value"). Anything after a #
160 character is treated as a comment. Options are
161 case-insensitive. C-style escaped characters are allowed inside quoted
162 values. To split one configuration entry into multiple lines, use a single
163 backslash character (\) before the end of the line. Comments can be used in
164 such multiline entries, but they must start at the beginning of a line.
166 Configuration options can be imported from files or folders using the %include
167 option with the value being a path. If the path is a file, the options from the
168 file will be parsed as if they were written where the %include option is. If
169 the path is a folder, all files on that folder will be parsed following lexical
170 order. Files starting with a dot are ignored. Files on subfolders are ignored.
171 The %include option can be used recursively.
173 By default, an option on the command line overrides an option found in the
174 configuration file, and an option in a configuration file overrides one in
177 This rule is simple for options that take a single value, but it can become
178 complicated for options that are allowed to occur more than once: if you
179 specify four SocksPorts in your configuration file, and one more SocksPort on
180 the command line, the option on the command line will replace __all__ of the
181 SocksPorts in the configuration file. If this isn't what you want, prefix
182 the option name with a plus sign (+), and it will be appended to the previous
183 set of options instead. For example, setting SocksPort 9100 will use only
184 port 9100, but setting +SocksPort 9100 will use ports 9100 and 9050 (because
185 this is the default).
187 Alternatively, you might want to remove every instance of an option in the
188 configuration file, and not replace it at all: you might want to say on the
189 command line that you want no SocksPorts at all. To do that, prefix the
190 option name with a forward slash (/). You can use the plus sign (+) and the
191 forward slash (/) in the configuration file and on the command line.
196 [[BandwidthRate]] **BandwidthRate** __N__ **bytes**|**KBytes**|**MBytes**|**GBytes**|**TBytes**|**KBits**|**MBits**|**GBits**|**TBits**::
197 A token bucket limits the average incoming bandwidth usage on this node
198 to the specified number of bytes per second, and the average outgoing
199 bandwidth usage to that same value. If you want to run a relay in the
200 public network, this needs to be _at the very least_ 75 KBytes for a
201 relay (that is, 600 kbits) or 50 KBytes for a bridge (400 kbits) -- but of
202 course, more is better; we recommend at least 250 KBytes (2 mbits) if
203 possible. (Default: 1 GByte) +
205 Note that this option, and other bandwidth-limiting options, apply to TCP
206 data only: They do not count TCP headers or DNS traffic. +
208 With this option, and in other options that take arguments in bytes,
209 KBytes, and so on, other formats are also supported. Notably, "KBytes" can
210 also be written as "kilobytes" or "kb"; "MBytes" can be written as
211 "megabytes" or "MB"; "kbits" can be written as "kilobits"; and so forth.
212 Tor also accepts "byte" and "bit" in the singular.
213 The prefixes "tera" and "T" are also recognized.
214 If no units are given, we default to bytes.
215 To avoid confusion, we recommend writing "bytes" or "bits" explicitly,
216 since it's easy to forget that "B" means bytes, not bits.
218 [[BandwidthBurst]] **BandwidthBurst** __N__ **bytes**|**KBytes**|**MBytes**|**GBytes**|**TBytes**|**KBits**|**MBits**|**GBits**|**TBits**::
219 Limit the maximum token bucket size (also known as the burst) to the given
220 number of bytes in each direction. (Default: 1 GByte)
222 [[MaxAdvertisedBandwidth]] **MaxAdvertisedBandwidth** __N__ **bytes**|**KBytes**|**MBytes**|**GBytes**|**TBytes**|**KBits**|**MBits**|**GBits**|**TBits**::
223 If set, we will not advertise more than this amount of bandwidth for our
224 BandwidthRate. Server operators who want to reduce the number of clients
225 who ask to build circuits through them (since this is proportional to
226 advertised bandwidth rate) can thus reduce the CPU demands on their server
227 without impacting network performance.
229 [[RelayBandwidthRate]] **RelayBandwidthRate** __N__ **bytes**|**KBytes**|**MBytes**|**GBytes**|**TBytes**|**KBits**|**MBits**|**GBits**|**TBits**::
230 If not 0, a separate token bucket limits the average incoming bandwidth
231 usage for \_relayed traffic_ on this node to the specified number of bytes
232 per second, and the average outgoing bandwidth usage to that same value.
233 Relayed traffic currently is calculated to include answers to directory
234 requests, but that may change in future versions. They do not include directory
235 fetches by the relay (from authority or other relays), because that is considered
236 "client" activity. (Default: 0)
238 [[RelayBandwidthBurst]] **RelayBandwidthBurst** __N__ **bytes**|**KBytes**|**MBytes**|**GBytes**|**TBytes**|**KBits**|**MBits**|**GBits**|**TBits**::
239 If not 0, limit the maximum token bucket size (also known as the burst) for
240 \_relayed traffic_ to the given number of bytes in each direction.
241 They do not include directory fetches by the relay (from authority
242 or other relays), because that is considered "client" activity. (Default: 0)
244 [[PerConnBWRate]] **PerConnBWRate** __N__ **bytes**|**KBytes**|**MBytes**|**GBytes**|**TBytes**|**KBits**|**MBits**|**GBits**|**TBits**::
245 If set, do separate rate limiting for each connection from a non-relay.
246 You should never need to change this value, since a network-wide value is
247 published in the consensus and your relay will use that value. (Default: 0)
249 [[PerConnBWBurst]] **PerConnBWBurst** __N__ **bytes**|**KBytes**|**MBytes**|**GBytes**|**TBytes**|**KBits**|**MBits**|**GBits**|**TBits**::
250 If set, do separate rate limiting for each connection from a non-relay.
251 You should never need to change this value, since a network-wide value is
252 published in the consensus and your relay will use that value. (Default: 0)
254 [[ClientTransportPlugin]] **ClientTransportPlugin** __transport__ socks4|socks5 __IP__:__PORT__::
255 **ClientTransportPlugin** __transport__ exec __path-to-binary__ [options]::
256 In its first form, when set along with a corresponding Bridge line, the Tor
257 client forwards its traffic to a SOCKS-speaking proxy on "IP:PORT".
258 (IPv4 addresses should written as-is; IPv6 addresses should be wrapped in
259 square brackets.) It's the
260 duty of that proxy to properly forward the traffic to the bridge. +
262 In its second form, when set along with a corresponding Bridge line, the Tor
263 client launches the pluggable transport proxy executable in
264 __path-to-binary__ using __options__ as its command-line options, and
265 forwards its traffic to it. It's the duty of that proxy to properly forward
266 the traffic to the bridge.
268 [[ServerTransportPlugin]] **ServerTransportPlugin** __transport__ exec __path-to-binary__ [options]::
269 The Tor relay launches the pluggable transport proxy in __path-to-binary__
270 using __options__ as its command-line options, and expects to receive
271 proxied client traffic from it.
273 [[ServerTransportListenAddr]] **ServerTransportListenAddr** __transport__ __IP__:__PORT__::
274 When this option is set, Tor will suggest __IP__:__PORT__ as the
275 listening address of any pluggable transport proxy that tries to
276 launch __transport__. (IPv4 addresses should written as-is; IPv6
277 addresses should be wrapped in square brackets.)
279 [[ServerTransportOptions]] **ServerTransportOptions** __transport__ __k=v__ __k=v__ ...::
280 When this option is set, Tor will pass the __k=v__ parameters to
281 any pluggable transport proxy that tries to launch __transport__. +
282 (Example: ServerTransportOptions obfs45 shared-secret=bridgepasswd cache=/var/lib/tor/cache)
284 [[ExtORPort]] **ExtORPort** \['address':]__port__|**auto**::
285 Open this port to listen for Extended ORPort connections from your
286 pluggable transports.
288 [[ExtORPortCookieAuthFile]] **ExtORPortCookieAuthFile** __Path__::
289 If set, this option overrides the default location and file name
290 for the Extended ORPort's cookie file -- the cookie file is needed
291 for pluggable transports to communicate through the Extended ORPort.
293 [[ExtORPortCookieAuthFileGroupReadable]] **ExtORPortCookieAuthFileGroupReadable** **0**|**1**::
294 If this option is set to 0, don't allow the filesystem group to read the
295 Extended OR Port cookie file. If the option is set to 1, make the cookie
296 file readable by the default GID. [Making the file readable by other
297 groups is not yet implemented; let us know if you need this for some
298 reason.] (Default: 0)
300 [[ConnLimit]] **ConnLimit** __NUM__::
301 The minimum number of file descriptors that must be available to the Tor
302 process before it will start. Tor will ask the OS for as many file
303 descriptors as the OS will allow (you can find this by "ulimit -H -n").
304 If this number is less than ConnLimit, then Tor will refuse to start. +
306 You probably don't need to adjust this. It has no effect on Windows
307 since that platform lacks getrlimit(). (Default: 1000)
309 [[DisableNetwork]] **DisableNetwork** **0**|**1**::
310 When this option is set, we don't listen for or accept any connections
311 other than controller connections, and we close (and don't reattempt)
313 connections. Controllers sometimes use this option to avoid using
314 the network until Tor is fully configured. (Default: 0)
316 [[ConstrainedSockets]] **ConstrainedSockets** **0**|**1**::
317 If set, Tor will tell the kernel to attempt to shrink the buffers for all
318 sockets to the size specified in **ConstrainedSockSize**. This is useful for
319 virtual servers and other environments where system level TCP buffers may
320 be limited. If you're on a virtual server, and you encounter the "Error
321 creating network socket: No buffer space available" message, you are
322 likely experiencing this problem. +
324 The preferred solution is to have the admin increase the buffer pool for
325 the host itself via /proc/sys/net/ipv4/tcp_mem or equivalent facility;
326 this configuration option is a second-resort. +
328 The DirPort option should also not be used if TCP buffers are scarce. The
329 cached directory requests consume additional sockets which exacerbates
332 You should **not** enable this feature unless you encounter the "no buffer
333 space available" issue. Reducing the TCP buffers affects window size for
334 the TCP stream and will reduce throughput in proportion to round trip
335 time on long paths. (Default: 0)
337 [[ConstrainedSockSize]] **ConstrainedSockSize** __N__ **bytes**|**KBytes**::
338 When **ConstrainedSockets** is enabled the receive and transmit buffers for
339 all sockets will be set to this limit. Must be a value between 2048 and
340 262144, in 1024 byte increments. Default of 8192 is recommended.
342 [[ControlPort]] **ControlPort** __PORT__|**unix:**__path__|**auto** [__flags__]::
343 If set, Tor will accept connections on this port and allow those
344 connections to control the Tor process using the Tor Control Protocol
345 (described in control-spec.txt in
346 https://spec.torproject.org[torspec]). Note: unless you also
347 specify one or more of **HashedControlPassword** or
348 **CookieAuthentication**, setting this option will cause Tor to allow
349 any process on the local host to control it. (Setting both authentication
350 methods means either method is sufficient to authenticate to Tor.) This
351 option is required for many Tor controllers; most use the value of 9051.
352 If a unix domain socket is used, you may quote the path using standard
354 Set it to "auto" to have Tor pick a port for you. (Default: 0) +
356 Recognized flags are...
358 Unix domain sockets only: makes the socket get created as
361 Unix domain sockets only: makes the socket get created as
363 **RelaxDirModeCheck**;;
364 Unix domain sockets only: Do not insist that the directory
365 that holds the socket be read-restricted.
367 [[ControlSocket]] **ControlSocket** __Path__::
368 Like ControlPort, but listens on a Unix domain socket, rather than a TCP
369 socket. '0' disables ControlSocket (Unix and Unix-like systems only.)
371 [[ControlSocketsGroupWritable]] **ControlSocketsGroupWritable** **0**|**1**::
372 If this option is set to 0, don't allow the filesystem group to read and
373 write unix sockets (e.g. ControlSocket). If the option is set to 1, make
374 the control socket readable and writable by the default GID. (Default: 0)
376 [[HashedControlPassword]] **HashedControlPassword** __hashed_password__::
377 Allow connections on the control port if they present
378 the password whose one-way hash is __hashed_password__. You
379 can compute the hash of a password by running "tor --hash-password
380 __password__". You can provide several acceptable passwords by using more
381 than one HashedControlPassword line.
383 [[CookieAuthentication]] **CookieAuthentication** **0**|**1**::
384 If this option is set to 1, allow connections on the control port
385 when the connecting process knows the contents of a file named
386 "control_auth_cookie", which Tor will create in its data directory. This
387 authentication method should only be used on systems with good filesystem
388 security. (Default: 0)
390 [[CookieAuthFile]] **CookieAuthFile** __Path__::
391 If set, this option overrides the default location and file name
392 for Tor's cookie file. (See CookieAuthentication above.)
394 [[CookieAuthFileGroupReadable]] **CookieAuthFileGroupReadable** **0**|**1**::
395 If this option is set to 0, don't allow the filesystem group to read the
396 cookie file. If the option is set to 1, make the cookie file readable by
397 the default GID. [Making the file readable by other groups is not yet
398 implemented; let us know if you need this for some reason.] (Default: 0)
400 [[ControlPortWriteToFile]] **ControlPortWriteToFile** __Path__::
401 If set, Tor writes the address and port of any control port it opens to
402 this address. Usable by controllers to learn the actual control port
403 when ControlPort is set to "auto".
405 [[ControlPortFileGroupReadable]] **ControlPortFileGroupReadable** **0**|**1**::
406 If this option is set to 0, don't allow the filesystem group to read the
407 control port file. If the option is set to 1, make the control port
408 file readable by the default GID. (Default: 0)
410 [[DataDirectory]] **DataDirectory** __DIR__::
411 Store working data in DIR. Can not be changed while tor is running.
412 (Default: ~/.tor if your home directory is not /; otherwise,
413 @LOCALSTATEDIR@/lib/tor. On Windows, the default is
414 your ApplicationData folder.)
416 [[DataDirectoryGroupReadable]] **DataDirectoryGroupReadable** **0**|**1**::
417 If this option is set to 0, don't allow the filesystem group to read the
418 DataDirectory. If the option is set to 1, make the DataDirectory readable
419 by the default GID. (Default: 0)
421 [[CacheDirectory]] **CacheDirectory** __DIR__::
422 Store cached directory data in DIR. Can not be changed while tor is
424 (Default: uses the value of DataDirectory.)
426 [[CacheDirectoryGroupReadable]] **CacheDirectoryGroupReadable** **0**|**1**::
427 If this option is set to 0, don't allow the filesystem group to read the
428 CacheDirectory. If the option is set to 1, make the CacheDirectory readable
429 by the default GID. (Default: 0)
431 [[FallbackDir]] **FallbackDir** __ipv4address__:__port__ orport=__port__ id=__fingerprint__ [weight=__num__] [ipv6=**[**__ipv6address__**]**:__orport__]::
432 When we're unable to connect to any directory cache for directory info
433 (usually because we don't know about any yet) we try a directory authority.
434 Clients also simultaneously try a FallbackDir, to avoid hangs on client
435 startup if a directory authority is down. Clients retry FallbackDirs more
436 often than directory authorities, to reduce the load on the directory
438 By default, the directory authorities are also FallbackDirs. Specifying a
439 FallbackDir replaces Tor's default hard-coded FallbackDirs (if any).
440 (See the **DirAuthority** entry for an explanation of each flag.)
442 [[UseDefaultFallbackDirs]] **UseDefaultFallbackDirs** **0**|**1**::
443 Use Tor's default hard-coded FallbackDirs (if any). (When a
444 FallbackDir line is present, it replaces the hard-coded FallbackDirs,
445 regardless of the value of UseDefaultFallbackDirs.) (Default: 1)
447 [[DirAuthority]] **DirAuthority** [__nickname__] [**flags**] __ipv4address__:__port__ __fingerprint__::
448 Use a nonstandard authoritative directory server at the provided address
449 and port, with the specified key fingerprint. This option can be repeated
450 many times, for multiple authoritative directory servers. Flags are
451 separated by spaces, and determine what kind of an authority this directory
452 is. By default, an authority is not authoritative for any directory style
453 or version unless an appropriate flag is given.
454 Tor will use this authority as a bridge authoritative directory if the
455 "bridge" flag is set. If a flag "orport=**port**" is given, Tor will use the
456 given port when opening encrypted tunnels to the dirserver. If a flag
457 "weight=**num**" is given, then the directory server is chosen randomly
458 with probability proportional to that weight (default 1.0). If a
459 flag "v3ident=**fp**" is given, the dirserver is a v3 directory authority
460 whose v3 long-term signing key has the fingerprint **fp**. Lastly,
461 if an "ipv6=**[**__ipv6address__**]**:__orport__" flag is present, then
463 authority is listening for IPv6 connections on the indicated IPv6 address
466 Tor will contact the authority at __ipv4address__ to
467 download directory documents. The provided __port__ value is a dirport;
468 clients ignore this in favor of the specified "orport=" value. If an
469 IPv6 ORPort is supplied, Tor will
470 also download directory documents at the IPv6 ORPort. +
472 If no **DirAuthority** line is given, Tor will use the default directory
473 authorities. NOTE: this option is intended for setting up a private Tor
474 network with its own directory authorities. If you use it, you will be
475 distinguishable from other users, because you won't believe the same
478 [[DirAuthorityFallbackRate]] **DirAuthorityFallbackRate** __NUM__::
479 When configured to use both directory authorities and fallback
480 directories, the directory authorities also work as fallbacks. They are
481 chosen with their regular weights, multiplied by this number, which
482 should be 1.0 or less. The default is less than 1, to reduce load on
483 authorities. (Default: 0.1)
485 [[AlternateDirAuthority]] **AlternateDirAuthority** [__nickname__] [**flags**] __ipv4address__:__port__ __fingerprint__ +
487 [[AlternateBridgeAuthority]] **AlternateBridgeAuthority** [__nickname__] [**flags**] __ipv4address__:__port__ __ fingerprint__::
488 These options behave as DirAuthority, but they replace fewer of the
489 default directory authorities. Using
490 AlternateDirAuthority replaces the default Tor directory authorities, but
491 leaves the default bridge authorities in
493 AlternateBridgeAuthority replaces the default bridge authority,
494 but leaves the directory authorities alone.
496 [[DisableAllSwap]] **DisableAllSwap** **0**|**1**::
497 If set to 1, Tor will attempt to lock all current and future memory pages,
498 so that memory cannot be paged out. Windows, OS X and Solaris are currently
499 not supported. We believe that this feature works on modern Gnu/Linux
500 distributions, and that it should work on *BSD systems (untested). This
501 option requires that you start your Tor as root, and you should use the
502 **User** option to properly reduce Tor's privileges.
503 Can not be changed while tor is running. (Default: 0)
505 [[DisableDebuggerAttachment]] **DisableDebuggerAttachment** **0**|**1**::
506 If set to 1, Tor will attempt to prevent basic debugging attachment attempts
507 by other processes. This may also keep Tor from generating core files if
508 it crashes. It has no impact for users who wish to attach if they
509 have CAP_SYS_PTRACE or if they are root. We believe that this feature
510 works on modern Gnu/Linux distributions, and that it may also work on *BSD
511 systems (untested). Some modern Gnu/Linux systems such as Ubuntu have the
512 kernel.yama.ptrace_scope sysctl and by default enable it as an attempt to
513 limit the PTRACE scope for all user processes by default. This feature will
514 attempt to limit the PTRACE scope for Tor specifically - it will not attempt
515 to alter the system wide ptrace scope as it may not even exist. If you wish
516 to attach to Tor with a debugger such as gdb or strace you will want to set
517 this to 0 for the duration of your debugging. Normal users should leave it
518 on. Disabling this option while Tor is running is prohibited. (Default: 1)
520 [[FetchDirInfoEarly]] **FetchDirInfoEarly** **0**|**1**::
521 If set to 1, Tor will always fetch directory information like other
522 directory caches, even if you don't meet the normal criteria for fetching
523 early. Normal users should leave it off. (Default: 0)
525 [[FetchDirInfoExtraEarly]] **FetchDirInfoExtraEarly** **0**|**1**::
526 If set to 1, Tor will fetch directory information before other directory
527 caches. It will attempt to download directory information closer to the
528 start of the consensus period. Normal users should leave it off.
531 [[FetchHidServDescriptors]] **FetchHidServDescriptors** **0**|**1**::
532 If set to 0, Tor will never fetch any hidden service descriptors from the
533 rendezvous directories. This option is only useful if you're using a Tor
534 controller that handles hidden service fetches for you. (Default: 1)
536 [[FetchServerDescriptors]] **FetchServerDescriptors** **0**|**1**::
537 If set to 0, Tor will never fetch any network status summaries or server
538 descriptors from the directory servers. This option is only useful if
539 you're using a Tor controller that handles directory fetches for you.
542 [[FetchUselessDescriptors]] **FetchUselessDescriptors** **0**|**1**::
543 If set to 1, Tor will fetch every consensus flavor, descriptor, and
544 certificate that it hears about. Otherwise, it will avoid fetching useless
545 descriptors: flavors that it is not using to build circuits, and authority
546 certificates it does not trust. This option is useful if you're using a
547 tor client with an external parser that uses a full consensus.
548 This option fetches all documents, **DirCache** fetches and serves
549 all documents. (Default: 0)
551 [[HTTPProxy]] **HTTPProxy** __host__[:__port__]::
552 Tor will make all its directory requests through this host:port (or host:80
553 if port is not specified), rather than connecting directly to any directory
554 servers. (DEPRECATED: As of 0.3.1.0-alpha you should use HTTPSProxy.)
556 [[HTTPProxyAuthenticator]] **HTTPProxyAuthenticator** __username:password__::
557 If defined, Tor will use this username:password for Basic HTTP proxy
558 authentication, as in RFC 2617. This is currently the only form of HTTP
559 proxy authentication that Tor supports; feel free to submit a patch if you
560 want it to support others. (DEPRECATED: As of 0.3.1.0-alpha you should use
561 HTTPSProxyAuthenticator.)
563 [[HTTPSProxy]] **HTTPSProxy** __host__[:__port__]::
564 Tor will make all its OR (SSL) connections through this host:port (or
565 host:443 if port is not specified), via HTTP CONNECT rather than connecting
566 directly to servers. You may want to set **FascistFirewall** to restrict
567 the set of ports you might try to connect to, if your HTTPS proxy only
568 allows connecting to certain ports.
570 [[HTTPSProxyAuthenticator]] **HTTPSProxyAuthenticator** __username:password__::
571 If defined, Tor will use this username:password for Basic HTTPS proxy
572 authentication, as in RFC 2617. This is currently the only form of HTTPS
573 proxy authentication that Tor supports; feel free to submit a patch if you
574 want it to support others.
576 [[Sandbox]] **Sandbox** **0**|**1**::
577 If set to 1, Tor will run securely through the use of a syscall sandbox.
578 Otherwise the sandbox will be disabled. The option is currently an
579 experimental feature. It only works on Linux-based operating systems,
580 and only when Tor has been built with the libseccomp library. This option
581 can not be changed while tor is running.
583 When the Sandbox is 1, the following options can not be changed when tor
589 ExtORPortCookieAuthFile
591 ServerDNSResolvConfFile
592 Tor must remain in client or server mode (some changes to ClientOnly and
593 ORPort are not allowed).
596 [[Socks4Proxy]] **Socks4Proxy** __host__[:__port__]::
597 Tor will make all OR connections through the SOCKS 4 proxy at host:port
598 (or host:1080 if port is not specified).
600 [[Socks5Proxy]] **Socks5Proxy** __host__[:__port__]::
601 Tor will make all OR connections through the SOCKS 5 proxy at host:port
602 (or host:1080 if port is not specified).
604 [[Socks5ProxyUsername]] **Socks5ProxyUsername** __username__ +
606 [[Socks5ProxyPassword]] **Socks5ProxyPassword** __password__::
607 If defined, authenticate to the SOCKS 5 server using username and password
608 in accordance to RFC 1929. Both username and password must be between 1 and
611 [[SocksSocketsGroupWritable]] **SocksSocketsGroupWritable** **0**|**1**::
612 If this option is set to 0, don't allow the filesystem group to read and
613 write unix sockets (e.g. SocksSocket). If the option is set to 1, make
614 the SocksSocket socket readable and writable by the default GID. (Default: 0)
616 [[KeepalivePeriod]] **KeepalivePeriod** __NUM__::
617 To keep firewalls from expiring connections, send a padding keepalive cell
618 every NUM seconds on open connections that are in use. If the connection
619 has no open circuits, it will instead be closed after NUM seconds of
620 idleness. (Default: 5 minutes)
622 [[Log]] **Log** __minSeverity__[-__maxSeverity__] **stderr**|**stdout**|**syslog**::
623 Send all messages between __minSeverity__ and __maxSeverity__ to the standard
624 output stream, the standard error stream, or to the system log. (The
625 "syslog" value is only supported on Unix.) Recognized severity levels are
626 debug, info, notice, warn, and err. We advise using "notice" in most cases,
627 since anything more verbose may provide sensitive information to an
628 attacker who obtains the logs. If only one severity level is given, all
629 messages of that level or higher will be sent to the listed destination.
631 [[Log2]] **Log** __minSeverity__[-__maxSeverity__] **file** __FILENAME__::
632 As above, but send log messages to the listed filename. The
633 "Log" option may appear more than once in a configuration file.
634 Messages are sent to all the logs that match their severity
637 [[Log3]] **Log** **[**__domain__,...**]**__minSeverity__[-__maxSeverity__] ... **file** __FILENAME__ +
639 [[Log4]] **Log** **[**__domain__,...**]**__minSeverity__[-__maxSeverity__] ... **stderr**|**stdout**|**syslog**::
640 As above, but select messages by range of log severity __and__ by a
641 set of "logging domains". Each logging domain corresponds to an area of
642 functionality inside Tor. You can specify any number of severity ranges
643 for a single log statement, each of them prefixed by a comma-separated
644 list of logging domains. You can prefix a domain with $$~$$ to indicate
645 negation, and use * to indicate "all domains". If you specify a severity
646 range without a list of domains, it matches all domains. +
648 This is an advanced feature which is most useful for debugging one or two
649 of Tor's subsystems at a time. +
651 The currently recognized domains are: general, crypto, net, config, fs,
652 protocol, mm, http, app, control, circ, rend, bug, dir, dirserv, or, edge,
653 acct, hist, and handshake. Domain names are case-insensitive. +
655 For example, "`Log [handshake]debug [~net,~mm]info notice stdout`" sends
656 to stdout: all handshake messages of any severity, all info-and-higher
657 messages from domains other than networking and memory management, and all
658 messages of severity notice or higher.
660 [[LogMessageDomains]] **LogMessageDomains** **0**|**1**::
661 If 1, Tor includes message domains with each log message. Every log
662 message currently has at least one domain; most currently have exactly
663 one. This doesn't affect controller log messages. (Default: 0)
665 [[MaxUnparseableDescSizeToLog]] **MaxUnparseableDescSizeToLog** __N__ **bytes**|**KBytes**|**MBytes**|**GBytes**|**TBytes**::
666 Unparseable descriptors (e.g. for votes, consensuses, routers) are logged
667 in separate files by hash, up to the specified size in total. Note that
668 only files logged during the lifetime of this Tor process count toward the
669 total; this is intended to be used to debug problems without opening live
670 servers to resource exhaustion attacks. (Default: 10 MB)
672 [[OutboundBindAddress]] **OutboundBindAddress** __IP__::
673 Make all outbound connections originate from the IP address specified. This
674 is only useful when you have multiple network interfaces, and you want all
675 of Tor's outgoing connections to use a single one. This option may
676 be used twice, once with an IPv4 address and once with an IPv6 address.
677 IPv6 addresses should be wrapped in square brackets.
678 This setting will be ignored for connections to the loopback addresses
679 (127.0.0.0/8 and ::1), and is not used for DNS requests as well.
681 [[OutboundBindAddressOR]] **OutboundBindAddressOR** __IP__::
682 Make all outbound non-exit (relay and other) connections
683 originate from the IP address specified. This option overrides
684 **OutboundBindAddress** for the same IP version. This option may
685 be used twice, once with an IPv4 address and once with an IPv6
686 address. IPv6 addresses should be wrapped in square brackets.
687 This setting will be ignored for connections to the loopback
688 addresses (127.0.0.0/8 and ::1).
690 [[OutboundBindAddressExit]] **OutboundBindAddressExit** __IP__::
691 Make all outbound exit connections originate from the IP address
692 specified. This option overrides **OutboundBindAddress** for the
693 same IP version. This option may be used twice, once with an IPv4
694 address and once with an IPv6 address.
695 IPv6 addresses should be wrapped in square brackets.
696 This setting will be ignored
697 for connections to the loopback addresses (127.0.0.0/8 and ::1).
699 [[PidFile]] **PidFile** __FILE__::
700 On startup, write our PID to FILE. On clean shutdown, remove
701 FILE. Can not be changed while tor is running.
703 [[ProtocolWarnings]] **ProtocolWarnings** **0**|**1**::
704 If 1, Tor will log with severity \'warn' various cases of other parties not
705 following the Tor specification. Otherwise, they are logged with severity
706 \'info'. (Default: 0)
708 [[RunAsDaemon]] **RunAsDaemon** **0**|**1**::
709 If 1, Tor forks and daemonizes to the background. This option has no effect
710 on Windows; instead you should use the --service command-line option.
711 Can not be changed while tor is running.
714 [[LogTimeGranularity]] **LogTimeGranularity** __NUM__::
715 Set the resolution of timestamps in Tor's logs to NUM milliseconds.
716 NUM must be positive and either a divisor or a multiple of 1 second.
717 Note that this option only controls the granularity written by Tor to
718 a file or console log. Tor does not (for example) "batch up" log
719 messages to affect times logged by a controller, times attached to
720 syslog messages, or the mtime fields on log files. (Default: 1 second)
722 [[TruncateLogFile]] **TruncateLogFile** **0**|**1**::
723 If 1, Tor will overwrite logs at startup and in response to a HUP signal,
724 instead of appending to them. (Default: 0)
726 [[SyslogIdentityTag]] **SyslogIdentityTag** __tag__::
727 When logging to syslog, adds a tag to the syslog identity such that
728 log entries are marked with "Tor-__tag__". Can not be changed while tor is
729 running. (Default: none)
731 [[AndroidIdentityTag]] **AndroidIdentityTag** __tag__::
732 When logging to Android's logging subsystem, adds a tag to the log identity
733 such that log entries are marked with "Tor-__tag__". Can not be changed while
734 tor is running. (Default: none)
736 [[SafeLogging]] **SafeLogging** **0**|**1**|**relay**::
737 Tor can scrub potentially sensitive strings from log messages (e.g.
738 addresses) by replacing them with the string [scrubbed]. This way logs can
739 still be useful, but they don't leave behind personally identifying
740 information about what sites a user might have visited. +
742 If this option is set to 0, Tor will not perform any scrubbing, if it is
743 set to 1, all potentially sensitive strings are replaced. If it is set to
744 relay, all log messages generated when acting as a relay are sanitized, but
745 all messages generated when acting as a client are not. (Default: 1)
747 [[User]] **User** __Username__::
748 On startup, setuid to this user and setgid to their primary group.
749 Can not be changed while tor is running.
751 [[KeepBindCapabilities]] **KeepBindCapabilities** **0**|**1**|**auto**::
752 On Linux, when we are started as root and we switch our identity using
753 the **User** option, the **KeepBindCapabilities** option tells us whether to
754 try to retain our ability to bind to low ports. If this value is 1, we
755 try to keep the capability; if it is 0 we do not; and if it is **auto**,
756 we keep the capability only if we are configured to listen on a low port.
757 Can not be changed while tor is running.
760 [[HardwareAccel]] **HardwareAccel** **0**|**1**::
761 If non-zero, try to use built-in (static) crypto hardware acceleration when
762 available. Can not be changed while tor is running. (Default: 0)
764 [[AccelName]] **AccelName** __NAME__::
765 When using OpenSSL hardware crypto acceleration attempt to load the dynamic
766 engine of this name. This must be used for any dynamic hardware engine.
767 Names can be verified with the openssl engine command. Can not be changed
768 while tor is running.
770 [[AccelDir]] **AccelDir** __DIR__::
771 Specify this option if using dynamic hardware acceleration and the engine
772 implementation library resides somewhere other than the OpenSSL default.
773 Can not be changed while tor is running.
775 [[AvoidDiskWrites]] **AvoidDiskWrites** **0**|**1**::
776 If non-zero, try to write to disk less frequently than we would otherwise.
777 This is useful when running on flash memory or other media that support
778 only a limited number of writes. (Default: 0)
780 [[CircuitPriorityHalflife]] **CircuitPriorityHalflife** __NUM1__::
781 If this value is set, we override the default algorithm for choosing which
782 circuit's cell to deliver or relay next. When the value is 0, we
783 round-robin between the active circuits on a connection, delivering one
784 cell from each in turn. When the value is positive, we prefer delivering
785 cells from whichever connection has the lowest weighted cell count, where
786 cells are weighted exponentially according to the supplied
787 CircuitPriorityHalflife value (in seconds). If this option is not set at
788 all, we use the behavior recommended in the current consensus
789 networkstatus. This is an advanced option; you generally shouldn't have
790 to mess with it. (Default: not set)
792 [[CountPrivateBandwidth]] **CountPrivateBandwidth** **0**|**1**::
793 If this option is set, then Tor's rate-limiting applies not only to
794 remote connections, but also to connections to private addresses like
795 127.0.0.1 or 10.0.0.1. This is mostly useful for debugging
796 rate-limiting. (Default: 0)
798 [[ExtendByEd25519ID]] **ExtendByEd25519ID** **0**|**1**|**auto**::
799 If this option is set to 1, we always try to include a relay's Ed25519 ID
800 when telling the proceeding relay in a circuit to extend to it.
801 If this option is set to 0, we never include Ed25519 IDs when extending
802 circuits. If the option is set to "default", we obey a
803 parameter in the consensus document. (Default: auto)
805 [[NoExec]] **NoExec** **0**|**1**::
806 If this option is set to 1, then Tor will never launch another
807 executable, regardless of the settings of PortForwardingHelper,
808 ClientTransportPlugin, or ServerTransportPlugin. Once this
809 option has been set to 1, it cannot be set back to 0 without
810 restarting Tor. (Default: 0)
812 [[Schedulers]] **Schedulers** **KIST**|**KISTLite**|**Vanilla**::
813 Specify the scheduler type that tor should use. The scheduler is
814 responsible for moving data around within a Tor process. This is an ordered
815 list by priority which means that the first value will be tried first and if
816 unavailable, the second one is tried and so on. It is possible to change
817 these values at runtime. This option mostly effects relays, and most
818 operators should leave it set to its default value.
819 (Default: KIST,KISTLite,Vanilla)
821 The possible scheduler types are:
823 **KIST**: Kernel-Informed Socket Transport. Tor will use TCP information
824 from the kernel to make informed decisions regarding how much data to send
825 and when to send it. KIST also handles traffic in batches (see
826 KISTSchedRunInterval) in order to improve traffic prioritization decisions.
827 As implemented, KIST will only work on Linux kernel version 2.6.39 or
830 **KISTLite**: Same as KIST but without kernel support. Tor will use all
831 the same mechanics as with KIST, including the batching, but its decisions
832 regarding how much data to send will not be as good. KISTLite will work on
833 all kernels and operating systems, and the majority of the benefits of KIST
834 are still realized with KISTLite.
836 **Vanilla**: The scheduler that Tor used before KIST was implemented. It
837 sends as much data as possible, as soon as possible. Vanilla will work on
838 all kernels and operating systems.
840 [[KISTSchedRunInterval]] **KISTSchedRunInterval** __NUM__ **msec**::
841 If KIST or KISTLite is used in the Schedulers option, this controls at which
842 interval the scheduler tick is. If the value is 0 msec, the value is taken
843 from the consensus if possible else it will fallback to the default 10
844 msec. Maximum possible value is 100 msec. (Default: 0 msec)
846 [[KISTSockBufSizeFactor]] **KISTSockBufSizeFactor** __NUM__::
847 If KIST is used in Schedulers, this is a multiplier of the per-socket
848 limit calculation of the KIST algorithm. (Default: 1.0)
853 The following options are useful only for clients (that is, if
854 **SocksPort**, **HTTPTunnelPort**, **TransPort**, **DNSPort**, or
855 **NATDPort** is non-zero):
857 [[Bridge]] **Bridge** [__transport__] __IP__:__ORPort__ [__fingerprint__]::
858 When set along with UseBridges, instructs Tor to use the relay at
859 "IP:ORPort" as a "bridge" relaying into the Tor network. If "fingerprint"
860 is provided (using the same format as for DirAuthority), we will verify that
861 the relay running at that location has the right fingerprint. We also use
862 fingerprint to look up the bridge descriptor at the bridge authority, if
863 it's provided and if UpdateBridgesFromAuthority is set too. +
865 If "transport" is provided, it must match a ClientTransportPlugin line. We
866 then use that pluggable transport's proxy to transfer data to the bridge,
867 rather than connecting to the bridge directly. Some transports use a
868 transport-specific method to work out the remote address to connect to.
869 These transports typically ignore the "IP:ORPort" specified in the bridge
872 Tor passes any "key=val" settings to the pluggable transport proxy as
873 per-connection arguments when connecting to the bridge. Consult
874 the documentation of the pluggable transport for details of what
875 arguments it supports.
877 [[LearnCircuitBuildTimeout]] **LearnCircuitBuildTimeout** **0**|**1**::
878 If 0, CircuitBuildTimeout adaptive learning is disabled. (Default: 1)
880 [[CircuitBuildTimeout]] **CircuitBuildTimeout** __NUM__::
882 Try for at most NUM seconds when building circuits. If the circuit isn't
883 open in that time, give up on it. If LearnCircuitBuildTimeout is 1, this
884 value serves as the initial value to use before a timeout is learned. If
885 LearnCircuitBuildTimeout is 0, this value is the only value used.
886 (Default: 60 seconds)
888 [[CircuitsAvailableTimeout]] **CircuitsAvailableTimeout** __NUM__::
889 Tor will attempt to keep at least one open, unused circuit available for
890 this amount of time. This option governs how long idle circuits are kept
891 open, as well as the amount of time Tor will keep a circuit open to each
892 of the recently used ports. This way when the Tor client is entirely
893 idle, it can expire all of its circuits, and then expire its TLS
894 connections. Note that the actual timeout value is uniformly randomized
895 from the specified value to twice that amount. (Default: 30 minutes;
898 [[CircuitStreamTimeout]] **CircuitStreamTimeout** __NUM__::
899 If non-zero, this option overrides our internal timeout schedule for how
900 many seconds until we detach a stream from a circuit and try a new circuit.
901 If your network is particularly slow, you might want to set this to a
902 number like 60. (Default: 0)
904 [[ClientOnly]] **ClientOnly** **0**|**1**::
905 If set to 1, Tor will not run as a relay or serve
906 directory requests, even if the ORPort, ExtORPort, or DirPort options are
907 set. (This config option is
908 mostly unnecessary: we added it back when we were considering having
909 Tor clients auto-promote themselves to being relays if they were stable
910 and fast enough. The current behavior is simply that Tor is a client
911 unless ORPort, ExtORPort, or DirPort are configured.) (Default: 0)
913 [[ConnectionPadding]] **ConnectionPadding** **0**|**1**|**auto**::
914 This option governs Tor's use of padding to defend against some forms of
915 traffic analysis. If it is set to 'auto', Tor will send padding only
916 if both the client and the relay support it. If it is set to 0, Tor will
917 not send any padding cells. If it is set to 1, Tor will still send padding
918 for client connections regardless of relay support. Only clients may set
919 this option. This option should be offered via the UI to mobile users
920 for use where bandwidth may be expensive.
923 [[ReducedConnectionPadding]] **ReducedConnectionPadding** **0**|**1**::
924 If set to 1, Tor will not not hold OR connections open for very long,
925 and will send less padding on these connections. Only clients may set
926 this option. This option should be offered via the UI to mobile users
927 for use where bandwidth may be expensive. (Default: 0)
929 [[ExcludeNodes]] **ExcludeNodes** __node__,__node__,__...__::
930 A list of identity fingerprints, country codes, and address
931 patterns of nodes to avoid when building a circuit. Country codes are
932 2-letter ISO3166 codes, and must
933 be wrapped in braces; fingerprints may be preceded by a dollar sign.
935 ExcludeNodes ABCD1234CDEF5678ABCD1234CDEF5678ABCD1234, \{cc}, 255.254.0.0/8) +
937 By default, this option is treated as a preference that Tor is allowed
938 to override in order to keep working.
939 For example, if you try to connect to a hidden service,
940 but you have excluded all of the hidden service's introduction points,
941 Tor will connect to one of them anyway. If you do not want this
942 behavior, set the StrictNodes option (documented below). +
944 Note also that if you are a relay, this (and the other node selection
945 options below) only affects your own circuits that Tor builds for you.
946 Clients can still build circuits through you to any node. Controllers
947 can tell Tor to build circuits through any node. +
949 Country codes are case-insensitive. The code "\{??}" refers to nodes whose
950 country can't be identified. No country code, including \{??}, works if
951 no GeoIPFile can be loaded. See also the GeoIPExcludeUnknown option below.
954 [[ExcludeExitNodes]] **ExcludeExitNodes** __node__,__node__,__...__::
955 A list of identity fingerprints, country codes, and address
956 patterns of nodes to never use when picking an exit node---that is, a
957 node that delivers traffic for you *outside* the Tor network. Note that any
958 node listed in ExcludeNodes is automatically considered to be part of this
960 the **ExcludeNodes** option for more information on how to specify
961 nodes. See also the caveats on the "ExitNodes" option below.
963 [[GeoIPExcludeUnknown]] **GeoIPExcludeUnknown** **0**|**1**|**auto**::
964 If this option is set to 'auto', then whenever any country code is set in
965 ExcludeNodes or ExcludeExitNodes, all nodes with unknown country (\{??} and
966 possibly \{A1}) are treated as excluded as well. If this option is set to
967 '1', then all unknown countries are treated as excluded in ExcludeNodes
968 and ExcludeExitNodes. This option has no effect when a GeoIP file isn't
969 configured or can't be found. (Default: auto)
971 [[ExitNodes]] **ExitNodes** __node__,__node__,__...__::
972 A list of identity fingerprints, country codes, and address
973 patterns of nodes to use as exit node---that is, a
974 node that delivers traffic for you *outside* the Tor network. See
975 the **ExcludeNodes** option for more information on how to specify nodes. +
977 Note that if you list too few nodes here, or if you exclude too many exit
978 nodes with ExcludeExitNodes, you can degrade functionality. For example,
979 if none of the exits you list allows traffic on port 80 or 443, you won't
980 be able to browse the web. +
982 Note also that not every circuit is used to deliver traffic *outside* of
983 the Tor network. It is normal to see non-exit circuits (such as those
984 used to connect to hidden services, those that do directory fetches,
985 those used for relay reachability self-tests, and so on) that end
986 at a non-exit node. To
987 keep a node from being used entirely, see ExcludeNodes and StrictNodes. +
989 The ExcludeNodes option overrides this option: any node listed in both
990 ExitNodes and ExcludeNodes is treated as excluded. +
992 The .exit address notation, if enabled via MapAddress, overrides
995 [[EntryNodes]] **EntryNodes** __node__,__node__,__...__::
996 A list of identity fingerprints and country codes of nodes
997 to use for the first hop in your normal circuits.
998 Normal circuits include all
999 circuits except for direct connections to directory servers. The Bridge
1000 option overrides this option; if you have configured bridges and
1001 UseBridges is 1, the Bridges are used as your entry nodes. +
1003 The ExcludeNodes option overrides this option: any node listed in both
1004 EntryNodes and ExcludeNodes is treated as excluded. See
1005 the **ExcludeNodes** option for more information on how to specify nodes.
1007 [[StrictNodes]] **StrictNodes** **0**|**1**::
1008 If StrictNodes is set to 1, Tor will treat solely the ExcludeNodes option
1009 as a requirement to follow for all the circuits you generate, even if
1010 doing so will break functionality for you (StrictNodes applies to neither
1011 ExcludeExitNodes nor to ExitNodes). If StrictNodes is set to 0, Tor will
1012 still try to avoid nodes in the ExcludeNodes list, but it will err on the
1013 side of avoiding unexpected errors. Specifically, StrictNodes 0 tells Tor
1014 that it is okay to use an excluded node when it is *necessary* to perform
1015 relay reachability self-tests, connect to a hidden service, provide a
1016 hidden service to a client, fulfill a .exit request, upload directory
1017 information, or download directory information. (Default: 0)
1019 [[FascistFirewall]] **FascistFirewall** **0**|**1**::
1020 If 1, Tor will only create outgoing connections to ORs running on ports
1021 that your firewall allows (defaults to 80 and 443; see **FirewallPorts**).
1022 This will allow you to run Tor as a client behind a firewall with
1023 restrictive policies, but will not allow you to run as a server behind such
1024 a firewall. If you prefer more fine-grained control, use
1025 ReachableAddresses instead.
1027 [[FirewallPorts]] **FirewallPorts** __PORTS__::
1028 A list of ports that your firewall allows you to connect to. Only used when
1029 **FascistFirewall** is set. This option is deprecated; use ReachableAddresses
1030 instead. (Default: 80, 443)
1032 [[ReachableAddresses]] **ReachableAddresses** __IP__[/__MASK__][:__PORT__]...::
1033 A comma-separated list of IP addresses and ports that your firewall allows
1034 you to connect to. The format is as for the addresses in ExitPolicy, except
1035 that "accept" is understood unless "reject" is explicitly provided. For
1036 example, \'ReachableAddresses 99.0.0.0/8, reject 18.0.0.0/8:80, accept
1037 \*:80' means that your firewall allows connections to everything inside net
1038 99, rejects port 80 connections to net 18, and accepts connections to port
1039 80 otherwise. (Default: \'accept \*:*'.)
1041 [[ReachableDirAddresses]] **ReachableDirAddresses** __IP__[/__MASK__][:__PORT__]...::
1042 Like **ReachableAddresses**, a list of addresses and ports. Tor will obey
1043 these restrictions when fetching directory information, using standard HTTP
1044 GET requests. If not set explicitly then the value of
1045 **ReachableAddresses** is used. If **HTTPProxy** is set then these
1046 connections will go through that proxy. (DEPRECATED: This option has
1047 had no effect for some time.)
1049 [[ReachableORAddresses]] **ReachableORAddresses** __IP__[/__MASK__][:__PORT__]...::
1050 Like **ReachableAddresses**, a list of addresses and ports. Tor will obey
1051 these restrictions when connecting to Onion Routers, using TLS/SSL. If not
1052 set explicitly then the value of **ReachableAddresses** is used. If
1053 **HTTPSProxy** is set then these connections will go through that proxy. +
1055 The separation between **ReachableORAddresses** and
1056 **ReachableDirAddresses** is only interesting when you are connecting
1057 through proxies (see **HTTPProxy** and **HTTPSProxy**). Most proxies limit
1058 TLS connections (which Tor uses to connect to Onion Routers) to port 443,
1059 and some limit HTTP GET requests (which Tor uses for fetching directory
1060 information) to port 80.
1062 [[HidServAuth]] **HidServAuth** __onion-address__ __auth-cookie__ [__service-name__]::
1063 Client authorization for a hidden service. Valid onion addresses contain 16
1064 characters in a-z2-7 plus ".onion", and valid auth cookies contain 22
1065 characters in A-Za-z0-9+/. The service name is only used for internal
1066 purposes, e.g., for Tor controllers. This option may be used multiple times
1067 for different hidden services. If a hidden service uses authorization and
1068 this option is not set, the hidden service is not accessible. Hidden
1069 services can be configured to require authorization using the
1070 **HiddenServiceAuthorizeClient** option.
1072 [[LongLivedPorts]] **LongLivedPorts** __PORTS__::
1073 A list of ports for services that tend to have long-running connections
1074 (e.g. chat and interactive shells). Circuits for streams that use these
1075 ports will contain only high-uptime nodes, to reduce the chance that a node
1076 will go down before the stream is finished. Note that the list is also
1077 honored for circuits (both client and service side) involving hidden
1078 services whose virtual port is in this list. (Default: 21, 22, 706,
1079 1863, 5050, 5190, 5222, 5223, 6523, 6667, 6697, 8300)
1081 [[MapAddress]] **MapAddress** __address__ __newaddress__::
1082 When a request for address arrives to Tor, it will transform to newaddress
1083 before processing it. For example, if you always want connections to
1084 www.example.com to exit via __torserver__ (where __torserver__ is the
1085 fingerprint of the server), use "MapAddress www.example.com
1086 www.example.com.torserver.exit". If the value is prefixed with a
1087 "\*.", matches an entire domain. For example, if you
1088 always want connections to example.com and any if its subdomains
1090 __torserver__ (where __torserver__ is the fingerprint of the server), use
1091 "MapAddress \*.example.com \*.example.com.torserver.exit". (Note the
1092 leading "*." in each part of the directive.) You can also redirect all
1093 subdomains of a domain to a single address. For example, "MapAddress
1094 *.example.com www.example.com". +
1098 1. When evaluating MapAddress expressions Tor stops when it hits the most
1099 recently added expression that matches the requested address. So if you
1100 have the following in your torrc, www.torproject.org will map to 1.1.1.1:
1102 MapAddress www.torproject.org 2.2.2.2
1103 MapAddress www.torproject.org 1.1.1.1
1105 2. Tor evaluates the MapAddress configuration until it finds no matches. So
1106 if you have the following in your torrc, www.torproject.org will map to
1109 MapAddress 1.1.1.1 2.2.2.2
1110 MapAddress www.torproject.org 1.1.1.1
1112 3. The following MapAddress expression is invalid (and will be
1113 ignored) because you cannot map from a specific address to a wildcard
1116 MapAddress www.torproject.org *.torproject.org.torserver.exit
1118 4. Using a wildcard to match only part of a string (as in *ample.com) is
1121 [[NewCircuitPeriod]] **NewCircuitPeriod** __NUM__::
1122 Every NUM seconds consider whether to build a new circuit. (Default: 30
1125 [[MaxCircuitDirtiness]] **MaxCircuitDirtiness** __NUM__::
1126 Feel free to reuse a circuit that was first used at most NUM seconds ago,
1127 but never attach a new stream to a circuit that is too old. For hidden
1128 services, this applies to the __last__ time a circuit was used, not the
1129 first. Circuits with streams constructed with SOCKS authentication via
1130 SocksPorts that have **KeepAliveIsolateSOCKSAuth** also remain alive
1131 for MaxCircuitDirtiness seconds after carrying the last such stream.
1132 (Default: 10 minutes)
1134 [[MaxClientCircuitsPending]] **MaxClientCircuitsPending** __NUM__::
1135 Do not allow more than NUM circuits to be pending at a time for handling
1136 client streams. A circuit is pending if we have begun constructing it,
1137 but it has not yet been completely constructed. (Default: 32)
1139 [[NodeFamily]] **NodeFamily** __node__,__node__,__...__::
1140 The Tor servers, defined by their identity fingerprints,
1141 constitute a "family" of similar or co-administered servers, so never use
1142 any two of them in the same circuit. Defining a NodeFamily is only needed
1143 when a server doesn't list the family itself (with MyFamily). This option
1144 can be used multiple times; each instance defines a separate family. In
1145 addition to nodes, you can also list IP address and ranges and country
1146 codes in {curly braces}. See the **ExcludeNodes** option for more
1147 information on how to specify nodes.
1149 [[EnforceDistinctSubnets]] **EnforceDistinctSubnets** **0**|**1**::
1150 If 1, Tor will not put two servers whose IP addresses are "too close" on
1151 the same circuit. Currently, two addresses are "too close" if they lie in
1152 the same /16 range. (Default: 1)
1154 [[SocksPort]] **SocksPort** \['address':]__port__|**unix:**__path__|**auto** [_flags_] [_isolation flags_]::
1155 Open this port to listen for connections from SOCKS-speaking
1156 applications. Set this to 0 if you don't want to allow application
1157 connections via SOCKS. Set it to "auto" to have Tor pick a port for
1158 you. This directive can be specified multiple times to bind
1159 to multiple addresses/ports. If a unix domain socket is used, you may
1160 quote the path using standard C escape sequences.
1163 NOTE: Although this option allows you to specify an IP address
1164 other than localhost, you should do so only with extreme caution.
1165 The SOCKS protocol is unencrypted and (as we use it)
1166 unauthenticated, so exposing it in this way could leak your
1167 information to anybody watching your network, and allow anybody
1168 to use your computer as an open proxy. +
1170 The _isolation flags_ arguments give Tor rules for which streams
1171 received on this SocksPort are allowed to share circuits with one
1172 another. Recognized isolation flags are:
1173 **IsolateClientAddr**;;
1174 Don't share circuits with streams from a different
1175 client address. (On by default and strongly recommended when
1176 supported; you can disable it with **NoIsolateClientAddr**.
1177 Unsupported and force-disabled when using Unix domain sockets.)
1178 **IsolateSOCKSAuth**;;
1179 Don't share circuits with streams for which different
1180 SOCKS authentication was provided. (For HTTPTunnelPort
1181 connections, this option looks at the Proxy-Authorization and
1182 X-Tor-Stream-Isolation headers. On by default;
1183 you can disable it with **NoIsolateSOCKSAuth**.)
1184 **IsolateClientProtocol**;;
1185 Don't share circuits with streams using a different protocol.
1186 (SOCKS 4, SOCKS 5, TransPort connections, NATDPort connections,
1187 and DNSPort requests are all considered to be different protocols.)
1188 **IsolateDestPort**;;
1189 Don't share circuits with streams targeting a different
1191 **IsolateDestAddr**;;
1192 Don't share circuits with streams targeting a different
1193 destination address.
1194 **KeepAliveIsolateSOCKSAuth**;;
1195 If **IsolateSOCKSAuth** is enabled, keep alive circuits while they have
1196 at least one stream with SOCKS authentication active. After such a circuit
1197 is idle for more than MaxCircuitDirtiness seconds, it can be closed.
1198 **SessionGroup=**__INT__;;
1199 If no other isolation rules would prevent it, allow streams
1200 on this port to share circuits with streams from every other
1201 port with the same session group. (By default, streams received
1202 on different SocksPorts, TransPorts, etc are always isolated from one
1203 another. This option overrides that behavior.)
1205 [[OtherSocksPortFlags]]::
1206 Other recognized __flags__ for a SocksPort are:
1208 Tell exits to not connect to IPv4 addresses in response to SOCKS
1209 requests on this connection.
1211 Tell exits to allow IPv6 addresses in response to SOCKS requests on
1212 this connection, so long as SOCKS5 is in use. (SOCKS4 can't handle
1215 Tells exits that, if a host has both an IPv4 and an IPv6 address,
1216 we would prefer to connect to it via IPv6. (IPv4 is the default.)
1218 Do not ask exits to resolve DNS addresses in SOCKS5 requests. Tor will
1219 connect to IPv4 addresses, IPv6 addresses (if IPv6Traffic is set) and
1221 **NoOnionTraffic**;;
1222 Do not connect to .onion addresses in SOCKS5 requests.
1223 **OnionTrafficOnly**;;
1224 Tell the tor client to only connect to .onion addresses in response to
1225 SOCKS5 requests on this connection. This is equivalent to NoDNSRequest,
1226 NoIPv4Traffic, NoIPv6Traffic. The corresponding NoOnionTrafficOnly
1227 flag is not supported.
1229 Tells the client to remember IPv4 DNS answers we receive from exit
1230 nodes via this connection. (On by default.)
1232 Tells the client to remember IPv6 DNS answers we receive from exit
1233 nodes via this connection.
1235 Unix domain sockets only: makes the socket get created as
1238 Unix domain sockets only: makes the socket get created as
1241 Tells the client to remember all DNS answers we receive from exit
1242 nodes via this connection.
1244 Tells the client to use any cached IPv4 DNS answers we have when making
1245 requests via this connection. (NOTE: This option, or UseIPv6Cache
1246 or UseDNSCache, can harm your anonymity, and probably
1247 won't help performance as much as you might expect. Use with care!)
1249 Tells the client to use any cached IPv6 DNS answers we have when making
1250 requests via this connection.
1252 Tells the client to use any cached DNS answers we have when making
1253 requests via this connection.
1254 **PreferIPv6Automap**;;
1255 When serving a hostname lookup request on this port that
1256 should get automapped (according to AutomapHostsOnResolve),
1257 if we could return either an IPv4 or an IPv6 answer, prefer
1258 an IPv6 answer. (On by default.)
1259 **PreferSOCKSNoAuth**;;
1260 Ordinarily, when an application offers both "username/password
1261 authentication" and "no authentication" to Tor via SOCKS5, Tor
1262 selects username/password authentication so that IsolateSOCKSAuth can
1263 work. This can confuse some applications, if they offer a
1264 username/password combination then get confused when asked for
1265 one. You can disable this behavior, so that Tor will select "No
1266 authentication" when IsolateSOCKSAuth is disabled, or when this
1269 [[SocksPortFlagsMisc]]::
1270 Flags are processed left to right. If flags conflict, the last flag on the
1271 line is used, and all earlier flags are ignored. No error is issued for
1274 [[SocksPolicy]] **SocksPolicy** __policy__,__policy__,__...__::
1275 Set an entrance policy for this server, to limit who can connect to the
1276 SocksPort and DNSPort ports. The policies have the same form as exit
1277 policies below, except that port specifiers are ignored. Any address
1278 not matched by some entry in the policy is accepted.
1280 [[SocksTimeout]] **SocksTimeout** __NUM__::
1281 Let a socks connection wait NUM seconds handshaking, and NUM seconds
1282 unattached waiting for an appropriate circuit, before we fail it. (Default:
1285 [[TokenBucketRefillInterval]] **TokenBucketRefillInterval** __NUM__ [**msec**|**second**]::
1286 Set the refill interval of Tor's token bucket to NUM milliseconds.
1287 NUM must be between 1 and 1000, inclusive. Note that the configured
1288 bandwidth limits are still expressed in bytes per second: this
1289 option only affects the frequency with which Tor checks to see whether
1290 previously exhausted connections may read again.
1291 Can not be changed while tor is running. (Default: 100 msec)
1293 [[TrackHostExits]] **TrackHostExits** __host__,__.domain__,__...__::
1294 For each value in the comma separated list, Tor will track recent
1295 connections to hosts that match this value and attempt to reuse the same
1296 exit node for each. If the value is prepended with a \'.\', it is treated as
1297 matching an entire domain. If one of the values is just a \'.', it means
1298 match everything. This option is useful if you frequently connect to sites
1299 that will expire all your authentication cookies (i.e. log you out) if
1300 your IP address changes. Note that this option does have the disadvantage
1301 of making it more clear that a given history is associated with a single
1302 user. However, most people who would wish to observe this will observe it
1303 through cookies or other protocol-specific means anyhow.
1305 [[TrackHostExitsExpire]] **TrackHostExitsExpire** __NUM__::
1306 Since exit servers go up and down, it is desirable to expire the
1307 association between host and exit server after NUM seconds. The default is
1308 1800 seconds (30 minutes).
1310 [[UpdateBridgesFromAuthority]] **UpdateBridgesFromAuthority** **0**|**1**::
1311 When set (along with UseBridges), Tor will try to fetch bridge descriptors
1312 from the configured bridge authorities when feasible. It will fall back to
1313 a direct request if the authority responds with a 404. (Default: 0)
1315 [[UseBridges]] **UseBridges** **0**|**1**::
1316 When set, Tor will fetch descriptors for each bridge listed in the "Bridge"
1317 config lines, and use these relays as both entry guards and directory
1318 guards. (Default: 0)
1320 [[UseEntryGuards]] **UseEntryGuards** **0**|**1**::
1321 If this option is set to 1, we pick a few long-term entry servers, and try
1322 to stick with them. This is desirable because constantly changing servers
1323 increases the odds that an adversary who owns some servers will observe a
1324 fraction of your paths. Entry Guards can not be used by Directory
1325 Authorities, Single Onion Services, and Tor2web clients. In these cases,
1326 the this option is ignored. (Default: 1)
1328 [[GuardfractionFile]] **GuardfractionFile** __FILENAME__::
1329 V3 authoritative directories only. Configures the location of the
1330 guardfraction file which contains information about how long relays
1331 have been guards. (Default: unset)
1333 [[UseGuardFraction]] **UseGuardFraction** **0**|**1**|**auto**::
1334 This torrc option specifies whether clients should use the
1335 guardfraction information found in the consensus during path
1336 selection. If it's set to 'auto', clients will do what the
1337 UseGuardFraction consensus parameter tells them to do. (Default: auto)
1339 [[NumEntryGuards]] **NumEntryGuards** __NUM__::
1340 If UseEntryGuards is set to 1, we will try to pick a total of NUM routers
1341 as long-term entries for our circuits. If NUM is 0, we try to learn the
1342 number from the guard-n-primary-guards-to-use consensus parameter, and
1343 default to 1 if the consensus parameter isn't set. (Default: 0)
1345 [[NumDirectoryGuards]] **NumDirectoryGuards** __NUM__::
1346 If UseEntryGuards is set to 1, we try to make sure we have at least NUM
1347 routers to use as directory guards. If this option is set to 0, use the
1348 value from the guard-n-primary-dir-guards-to-use consensus parameter, and
1349 default to 3 if the consensus parameter isn't set. (Default: 0)
1351 [[GuardLifetime]] **GuardLifetime** __N__ **days**|**weeks**|**months**::
1352 If nonzero, and UseEntryGuards is set, minimum time to keep a guard before
1353 picking a new one. If zero, we use the GuardLifetime parameter from the
1354 consensus directory. No value here may be less than 1 month or greater
1355 than 5 years; out-of-range values are clamped. (Default: 0)
1357 [[SafeSocks]] **SafeSocks** **0**|**1**::
1358 When this option is enabled, Tor will reject application connections that
1359 use unsafe variants of the socks protocol -- ones that only provide an IP
1360 address, meaning the application is doing a DNS resolve first.
1361 Specifically, these are socks4 and socks5 when not doing remote DNS.
1364 [[TestSocks]] **TestSocks** **0**|**1**::
1365 When this option is enabled, Tor will make a notice-level log entry for
1366 each connection to the Socks port indicating whether the request used a
1367 safe socks protocol or an unsafe one (see above entry on SafeSocks). This
1368 helps to determine whether an application using Tor is possibly leaking
1369 DNS requests. (Default: 0)
1371 [[VirtualAddrNetworkIPv4]] **VirtualAddrNetworkIPv4** __IPv4Address__/__bits__ +
1373 [[VirtualAddrNetworkIPv6]] **VirtualAddrNetworkIPv6** [__IPv6Address__]/__bits__::
1374 When Tor needs to assign a virtual (unused) address because of a MAPADDRESS
1375 command from the controller or the AutomapHostsOnResolve feature, Tor
1376 picks an unassigned address from this range. (Defaults:
1377 127.192.0.0/10 and [FE80::]/10 respectively.) +
1379 When providing proxy server service to a network of computers using a tool
1380 like dns-proxy-tor, change the IPv4 network to "10.192.0.0/10" or
1381 "172.16.0.0/12" and change the IPv6 network to "[FC00::]/7".
1382 The default **VirtualAddrNetwork** address ranges on a
1383 properly configured machine will route to the loopback or link-local
1384 interface. The maximum number of bits for the network prefix is set to 104
1385 for IPv6 and 16 for IPv4. However, a wider network - smaller prefix length
1386 - is preferable since it reduces the chances for an attacker to guess the
1387 used IP. For local use, no change to the default VirtualAddrNetwork setting
1390 [[AllowNonRFC953Hostnames]] **AllowNonRFC953Hostnames** **0**|**1**::
1391 When this option is disabled, Tor blocks hostnames containing illegal
1392 characters (like @ and :) rather than sending them to an exit node to be
1393 resolved. This helps trap accidental attempts to resolve URLs and so on.
1396 [[HTTPTunnelPort]] **HTTPTunnelPort** \['address':]__port__|**auto** [_isolation flags_]::
1397 Open this port to listen for proxy connections using the "HTTP CONNECT"
1398 protocol instead of SOCKS. Set this to 0
1399 0 if you don't want to allow "HTTP CONNECT" connections. Set the port
1400 to "auto" to have Tor pick a port for you. This directive can be
1401 specified multiple times to bind to multiple addresses/ports. See
1402 SOCKSPort for an explanation of isolation flags. (Default: 0)
1404 [[TransPort]] **TransPort** \['address':]__port__|**auto** [_isolation flags_]::
1405 Open this port to listen for transparent proxy connections. Set this to
1406 0 if you don't want to allow transparent proxy connections. Set the port
1407 to "auto" to have Tor pick a port for you. This directive can be
1408 specified multiple times to bind to multiple addresses/ports. See
1409 SOCKSPort for an explanation of isolation flags. +
1411 TransPort requires OS support for transparent proxies, such as BSDs' pf or
1412 Linux's IPTables. If you're planning to use Tor as a transparent proxy for
1413 a network, you'll want to examine and change VirtualAddrNetwork from the
1414 default setting. (Default: 0)
1416 [[TransProxyType]] **TransProxyType** **default**|**TPROXY**|**ipfw**|**pf-divert**::
1417 TransProxyType may only be enabled when there is transparent proxy listener
1420 Set this to "TPROXY" if you wish to be able to use the TPROXY Linux module
1421 to transparently proxy connections that are configured using the TransPort
1422 option. Detailed information on how to configure the TPROXY
1423 feature can be found in the Linux kernel source tree in the file
1424 Documentation/networking/tproxy.txt. +
1426 Set this option to "ipfw" to use the FreeBSD ipfw interface. +
1428 On *BSD operating systems when using pf, set this to "pf-divert" to take
1429 advantage of +divert-to+ rules, which do not modify the packets like
1430 +rdr-to+ rules do. Detailed information on how to configure pf to use
1431 +divert-to+ rules can be found in the pf.conf(5) manual page. On OpenBSD,
1432 +divert-to+ is available to use on versions greater than or equal to
1435 Set this to "default", or leave it unconfigured, to use regular IPTables
1436 on Linux, or to use pf +rdr-to+ rules on *BSD systems. +
1438 (Default: "default".)
1440 [[NATDPort]] **NATDPort** \['address':]__port__|**auto** [_isolation flags_]::
1441 Open this port to listen for connections from old versions of ipfw (as
1442 included in old versions of FreeBSD, etc) using the NATD protocol.
1443 Use 0 if you don't want to allow NATD connections. Set the port
1444 to "auto" to have Tor pick a port for you. This directive can be
1445 specified multiple times to bind to multiple addresses/ports. See
1446 SocksPort for an explanation of isolation flags. +
1448 This option is only for people who cannot use TransPort. (Default: 0)
1450 [[AutomapHostsOnResolve]] **AutomapHostsOnResolve** **0**|**1**::
1451 When this option is enabled, and we get a request to resolve an address
1452 that ends with one of the suffixes in **AutomapHostsSuffixes**, we map an
1453 unused virtual address to that address, and return the new virtual address.
1454 This is handy for making ".onion" addresses work with applications that
1455 resolve an address and then connect to it. (Default: 0)
1457 [[AutomapHostsSuffixes]] **AutomapHostsSuffixes** __SUFFIX__,__SUFFIX__,__...__::
1458 A comma-separated list of suffixes to use with **AutomapHostsOnResolve**.
1459 The "." suffix is equivalent to "all addresses." (Default: .exit,.onion).
1461 [[DNSPort]] **DNSPort** \['address':]__port__|**auto** [_isolation flags_]::
1462 If non-zero, open this port to listen for UDP DNS requests, and resolve
1463 them anonymously. This port only handles A, AAAA, and PTR requests---it
1464 doesn't handle arbitrary DNS request types. Set the port to "auto" to
1465 have Tor pick a port for
1466 you. This directive can be specified multiple times to bind to multiple
1467 addresses/ports. See SocksPort for an explanation of isolation
1470 [[ClientDNSRejectInternalAddresses]] **ClientDNSRejectInternalAddresses** **0**|**1**::
1471 If true, Tor does not believe any anonymously retrieved DNS answer that
1472 tells it that an address resolves to an internal address (like 127.0.0.1 or
1473 192.168.0.1). This option prevents certain browser-based attacks; it
1474 is not allowed to be set on the default network. (Default: 1)
1476 [[ClientRejectInternalAddresses]] **ClientRejectInternalAddresses** **0**|**1**::
1477 If true, Tor does not try to fulfill requests to connect to an internal
1478 address (like 127.0.0.1 or 192.168.0.1) __unless an exit node is
1479 specifically requested__ (for example, via a .exit hostname, or a
1480 controller request). If true, multicast DNS hostnames for machines on the
1481 local network (of the form *.local) are also rejected. (Default: 1)
1483 [[DownloadExtraInfo]] **DownloadExtraInfo** **0**|**1**::
1484 If true, Tor downloads and caches "extra-info" documents. These documents
1485 contain information about servers other than the information in their
1486 regular server descriptors. Tor does not use this information for anything
1487 itself; to save bandwidth, leave this option turned off. (Default: 0)
1489 [[WarnPlaintextPorts]] **WarnPlaintextPorts** __port__,__port__,__...__::
1490 Tells Tor to issue a warnings whenever the user tries to make an anonymous
1491 connection to one of these ports. This option is designed to alert users
1492 to services that risk sending passwords in the clear. (Default:
1495 [[RejectPlaintextPorts]] **RejectPlaintextPorts** __port__,__port__,__...__::
1496 Like WarnPlaintextPorts, but instead of warning about risky port uses, Tor
1497 will instead refuse to make the connection. (Default: None)
1499 [[OptimisticData]] **OptimisticData** **0**|**1**|**auto**::
1500 When this option is set, and Tor is using an exit node that supports
1501 the feature, it will try optimistically to send data to the exit node
1502 without waiting for the exit node to report whether the connection
1503 succeeded. This can save a round-trip time for protocols like HTTP
1504 where the client talks first. If OptimisticData is set to **auto**,
1505 Tor will look at the UseOptimisticData parameter in the networkstatus.
1508 [[Tor2webMode]] **Tor2webMode** **0**|**1**::
1509 When this option is set, Tor connects to hidden services
1510 **non-anonymously**. This option also disables client connections to
1511 non-hidden-service hostnames through Tor. It **must only** be used when
1512 running a tor2web Hidden Service web proxy.
1513 To enable this option the compile time flag --enable-tor2web-mode must be
1514 specified. Since Tor2webMode is non-anonymous, you can not run an
1515 anonymous Hidden Service on a tor version compiled with Tor2webMode.
1518 [[Tor2webRendezvousPoints]] **Tor2webRendezvousPoints** __node__,__node__,__...__::
1519 A list of identity fingerprints, nicknames, country codes and
1520 address patterns of nodes that are allowed to be used as RPs
1521 in HS circuits; any other nodes will not be used as RPs.
1523 Tor2webRendezvousPoints Fastyfasty, ABCD1234CDEF5678ABCD1234CDEF5678ABCD1234, \{cc}, 255.254.0.0/8) +
1525 This feature can only be used if Tor2webMode is also enabled. +
1527 ExcludeNodes have higher priority than Tor2webRendezvousPoints,
1528 which means that nodes specified in ExcludeNodes will not be
1531 If no nodes in Tor2webRendezvousPoints are currently available for
1532 use, Tor will choose a random node when building HS circuits.
1534 [[_HSLayer2Nodes]] **_HSLayer2Nodes** __node__,__node__,__...__::
1535 A list of identity fingerprints, nicknames, country codes, and
1536 address patterns of nodes that are allowed to be used as the
1537 second hop in all client or service-side Onion Service circuits.
1538 This option mitigates attacks where the adversary runs middle nodes
1539 and induces your client or service to create many circuits, in order
1540 to discover your primary guard node.
1541 (Default: Any node in the network may be used in the second hop.)
1544 _HSLayer2Nodes ABCD1234CDEF5678ABCD1234CDEF5678ABCD1234, \{cc}, 255.254.0.0/8) +
1546 When this is set, the resulting hidden service paths will
1549 C - G - L2 - M - Rend +
1550 C - G - L2 - M - HSDir +
1551 C - G - L2 - M - Intro +
1552 S - G - L2 - M - Rend +
1553 S - G - L2 - M - HSDir +
1554 S - G - L2 - M - Intro +
1556 where C is this client, S is the service, G is the Guard node,
1557 L2 is a node from this option, and M is a random middle node.
1558 Rend, HSDir, and Intro point selection is not affected by this
1561 This option may be combined with _HSLayer3Nodes to create
1564 C - G - L2 - L3 - Rend +
1565 C - G - L2 - L3 - M - HSDir +
1566 C - G - L2 - L3 - M - Intro +
1567 S - G - L2 - L3 - M - Rend +
1568 S - G - L2 - L3 - HSDir +
1569 S - G - L2 - L3 - Intro +
1571 ExcludeNodes have higher priority than _HSLayer2Nodes,
1572 which means that nodes specified in ExcludeNodes will not be
1575 This option is meant to be managed by a Tor controller such as
1576 https://github.com/mikeperry-tor/vanguards that selects and
1577 updates this set of nodes for you. Hence it does not do load
1578 balancing if fewer than 20 nodes are selected, and if no nodes in
1579 _HSLayer2Nodes are currently available for use, Tor will not work.
1580 Please use extreme care if you are setting this option manually.
1582 [[_HSLayer3Nodes]] **_HSLayer3Nodes** __node__,__node__,__...__::
1583 A list of identity fingerprints, nicknames, country codes, and
1584 address patterns of nodes that are allowed to be used as the
1585 third hop in all client and service-side Onion Service circuits.
1586 This option mitigates attacks where the adversary runs middle nodes
1587 and induces your client or service to create many circuits, in order
1588 to discover your primary or Layer2 guard nodes.
1589 (Default: Any node in the network may be used in the third hop.)
1592 _HSLayer3Nodes ABCD1234CDEF5678ABCD1234CDEF5678ABCD1234, \{cc}, 255.254.0.0/8) +
1594 When this is set by itself, the resulting hidden service paths
1596 C - G - M - L3 - Rend +
1597 C - G - M - L3 - M - HSDir +
1598 C - G - M - L3 - M - Intro +
1599 S - G - M - L3 - M - Rend +
1600 S - G - M - L3 - HSDir +
1601 S - G - M - L3 - Intro +
1602 where C is this client, S is the service, G is the Guard node,
1603 L2 is a node from this option, and M is a random middle node.
1604 Rend, HSDir, and Intro point selection is not affected by this
1607 While it is possible to use this option by itself, it should be
1608 combined with _HSLayer2Nodes to create paths of the form:
1610 C - G - L2 - L3 - Rend +
1611 C - G - L2 - L3 - M - HSDir +
1612 C - G - L2 - L3 - M - Intro +
1613 S - G - L2 - L3 - M - Rend +
1614 S - G - L2 - L3 - HSDir +
1615 S - G - L2 - L3 - Intro +
1617 ExcludeNodes have higher priority than _HSLayer3Nodes,
1618 which means that nodes specified in ExcludeNodes will not be
1621 This option is meant to be managed by a Tor controller such as
1622 https://github.com/mikeperry-tor/vanguards that selects and
1623 updates this set of nodes for you. Hence it does not do load
1624 balancing if fewer than 20 nodes are selected, and if no nodes in
1625 _HSLayer3Nodes are currently available for use, Tor will not work.
1626 Please use extreme care if you are setting this option manually.
1628 [[UseMicrodescriptors]] **UseMicrodescriptors** **0**|**1**|**auto**::
1629 Microdescriptors are a smaller version of the information that Tor needs
1630 in order to build its circuits. Using microdescriptors makes Tor clients
1631 download less directory information, thus saving bandwidth. Directory
1632 caches need to fetch regular descriptors and microdescriptors, so this
1633 option doesn't save any bandwidth for them. If this option is set to
1634 "auto" (recommended) then it is on for all clients that do not set
1635 FetchUselessDescriptors. (Default: auto)
1637 [[PathBiasCircThreshold]] **PathBiasCircThreshold** __NUM__ +
1639 [[PathBiasNoticeRate]] **PathBiasNoticeRate** __NUM__ +
1641 [[PathBiasWarnRate]] **PathBiasWarnRate** __NUM__ +
1643 [[PathBiasExtremeRate]] **PathBiasExtremeRate** __NUM__ +
1645 [[PathBiasDropGuards]] **PathBiasDropGuards** __NUM__ +
1647 [[PathBiasScaleThreshold]] **PathBiasScaleThreshold** __NUM__::
1648 These options override the default behavior of Tor's (**currently
1649 experimental**) path bias detection algorithm. To try to find broken or
1650 misbehaving guard nodes, Tor looks for nodes where more than a certain
1651 fraction of circuits through that guard fail to get built. +
1653 The PathBiasCircThreshold option controls how many circuits we need to build
1654 through a guard before we make these checks. The PathBiasNoticeRate,
1655 PathBiasWarnRate and PathBiasExtremeRate options control what fraction of
1656 circuits must succeed through a guard so we won't write log messages.
1657 If less than PathBiasExtremeRate circuits succeed *and* PathBiasDropGuards
1658 is set to 1, we disable use of that guard. +
1660 When we have seen more than PathBiasScaleThreshold
1661 circuits through a guard, we scale our observations by 0.5 (governed by
1662 the consensus) so that new observations don't get swamped by old ones. +
1664 By default, or if a negative value is provided for one of these options,
1665 Tor uses reasonable defaults from the networkstatus consensus document.
1666 If no defaults are available there, these options default to 150, .70,
1667 .50, .30, 0, and 300 respectively.
1669 [[PathBiasUseThreshold]] **PathBiasUseThreshold** __NUM__ +
1671 [[PathBiasNoticeUseRate]] **PathBiasNoticeUseRate** __NUM__ +
1673 [[PathBiasExtremeUseRate]] **PathBiasExtremeUseRate** __NUM__ +
1675 [[PathBiasScaleUseThreshold]] **PathBiasScaleUseThreshold** __NUM__::
1676 Similar to the above options, these options override the default behavior
1677 of Tor's (**currently experimental**) path use bias detection algorithm. +
1679 Where as the path bias parameters govern thresholds for successfully
1680 building circuits, these four path use bias parameters govern thresholds
1681 only for circuit usage. Circuits which receive no stream usage
1682 are not counted by this detection algorithm. A used circuit is considered
1683 successful if it is capable of carrying streams or otherwise receiving
1684 well-formed responses to RELAY cells. +
1686 By default, or if a negative value is provided for one of these options,
1687 Tor uses reasonable defaults from the networkstatus consensus document.
1688 If no defaults are available there, these options default to 20, .80,
1689 .60, and 100, respectively.
1691 [[ClientUseIPv4]] **ClientUseIPv4** **0**|**1**::
1692 If this option is set to 0, Tor will avoid connecting to directory servers
1693 and entry nodes over IPv4. Note that clients with an IPv4
1694 address in a **Bridge**, proxy, or pluggable transport line will try
1695 connecting over IPv4 even if **ClientUseIPv4** is set to 0. (Default: 1)
1697 [[ClientUseIPv6]] **ClientUseIPv6** **0**|**1**::
1698 If this option is set to 1, Tor might connect to directory servers or
1699 entry nodes over IPv6. Note that clients configured with an IPv6 address
1700 in a **Bridge**, proxy, or pluggable transport line will try connecting
1701 over IPv6 even if **ClientUseIPv6** is set to 0. (Default: 0)
1703 [[ClientPreferIPv6DirPort]] **ClientPreferIPv6DirPort** **0**|**1**|**auto**::
1704 If this option is set to 1, Tor prefers a directory port with an IPv6
1705 address over one with IPv4, for direct connections, if a given directory
1706 server has both. (Tor also prefers an IPv6 DirPort if IPv4Client is set to
1707 0.) If this option is set to auto, clients prefer IPv4. Other things may
1708 influence the choice. This option breaks a tie to the favor of IPv6.
1709 (Default: auto) (DEPRECATED: This option has had no effect for some
1712 [[ClientPreferIPv6ORPort]] **ClientPreferIPv6ORPort** **0**|**1**|**auto**::
1713 If this option is set to 1, Tor prefers an OR port with an IPv6
1714 address over one with IPv4 if a given entry node has both. (Tor also
1715 prefers an IPv6 ORPort if IPv4Client is set to 0.) If this option is set
1716 to auto, Tor bridge clients prefer the configured bridge address, and
1717 other clients prefer IPv4. Other things may influence the choice. This
1718 option breaks a tie to the favor of IPv6. (Default: auto)
1720 [[PathsNeededToBuildCircuits]] **PathsNeededToBuildCircuits** __NUM__::
1721 Tor clients don't build circuits for user traffic until they know
1722 about enough of the network so that they could potentially construct
1723 enough of the possible paths through the network. If this option
1724 is set to a fraction between 0.25 and 0.95, Tor won't build circuits
1725 until it has enough descriptors or microdescriptors to construct
1726 that fraction of possible paths. Note that setting this option too low
1727 can make your Tor client less anonymous, and setting it too high can
1728 prevent your Tor client from bootstrapping. If this option is negative,
1729 Tor will use a default value chosen by the directory authorities. If the
1730 directory authorities do not choose a value, Tor will default to 0.6.
1733 [[ClientBootstrapConsensusAuthorityDownloadSchedule]] **ClientBootstrapConsensusAuthorityDownloadSchedule** __N__,__N__,__...__::
1734 Schedule for when clients should download consensuses from authorities
1735 if they are bootstrapping (that is, they don't have a usable, reasonably
1736 live consensus). Only used by clients fetching from a list of fallback
1737 directory mirrors. This schedule is advanced by (potentially concurrent)
1738 connection attempts, unlike other schedules, which are advanced by
1739 connection failures. (Default: 6, 11, 3600, 10800, 25200, 54000, 111600,
1742 [[ClientBootstrapConsensusFallbackDownloadSchedule]] **ClientBootstrapConsensusFallbackDownloadSchedule** __N__,__N__,__...__::
1743 Schedule for when clients should download consensuses from fallback
1744 directory mirrors if they are bootstrapping (that is, they don't have a
1745 usable, reasonably live consensus). Only used by clients fetching from a
1746 list of fallback directory mirrors. This schedule is advanced by
1747 (potentially concurrent) connection attempts, unlike other schedules,
1748 which are advanced by connection failures. (Default: 0, 1, 4, 11, 3600,
1749 10800, 25200, 54000, 111600, 262800)
1751 [[ClientBootstrapConsensusAuthorityOnlyDownloadSchedule]] **ClientBootstrapConsensusAuthorityOnlyDownloadSchedule** __N__,__N__,__...__::
1752 Schedule for when clients should download consensuses from authorities
1753 if they are bootstrapping (that is, they don't have a usable, reasonably
1754 live consensus). Only used by clients which don't have or won't fetch
1755 from a list of fallback directory mirrors. This schedule is advanced by
1756 (potentially concurrent) connection attempts, unlike other schedules,
1757 which are advanced by connection failures. (Default: 0, 3, 7, 3600,
1758 10800, 25200, 54000, 111600, 262800)
1760 [[ClientBootstrapConsensusMaxDownloadTries]] **ClientBootstrapConsensusMaxDownloadTries** __NUM__::
1761 Try this many times to download a consensus while bootstrapping using
1762 fallback directory mirrors before giving up. (Default: 7)
1764 [[ClientBootstrapConsensusAuthorityOnlyMaxDownloadTries]] **ClientBootstrapConsensusAuthorityOnlyMaxDownloadTries** __NUM__::
1765 Try this many times to download a consensus while bootstrapping using
1766 authorities before giving up. (Default: 4)
1768 [[ClientBootstrapConsensusMaxInProgressTries]] **ClientBootstrapConsensusMaxInProgressTries** __NUM__::
1769 Try this many simultaneous connections to download a consensus before
1770 waiting for one to complete, timeout, or error out. (Default: 3)
1775 The following options are useful only for servers (that is, if ORPort
1778 [[Address]] **Address** __address__::
1779 The IPv4 address of this server, or a fully qualified domain name of
1780 this server that resolves to an IPv4 address. You can leave this
1781 unset, and Tor will try to guess your IPv4 address. This IPv4
1782 address is the one used to tell clients and other servers where to
1783 find your Tor server; it doesn't affect the address that your server
1784 binds to. To bind to a different address, use the ORPort and
1785 OutboundBindAddress options.
1787 [[AssumeReachable]] **AssumeReachable** **0**|**1**::
1788 This option is used when bootstrapping a new Tor network. If set to 1,
1789 don't do self-reachability testing; just upload your server descriptor
1790 immediately. If **AuthoritativeDirectory** is also set, this option
1791 instructs the dirserver to bypass remote reachability testing too and list
1792 all connected servers as running.
1794 [[BridgeRelay]] **BridgeRelay** **0**|**1**::
1795 Sets the relay to act as a "bridge" with respect to relaying connections
1796 from bridge users to the Tor network. It mainly causes Tor to publish a
1797 server descriptor to the bridge database, rather than
1798 to the public directory authorities.
1800 [[BridgeDistribution]] **BridgeDistribution** __string__::
1801 If set along with BridgeRelay, Tor will include a new line in its
1802 bridge descriptor which indicates to the BridgeDB service how it
1803 would like its bridge address to be given out. Set it to "none" if
1804 you want BridgeDB to avoid distributing your bridge address, or "any" to
1805 let BridgeDB decide. (Default: any)
1807 Note: as of Oct 2017, the BridgeDB part of this option is not yet
1808 implemented. Until BridgeDB is updated to obey this option, your
1809 bridge will make this request, but it will not (yet) be obeyed.
1811 [[ContactInfo]] **ContactInfo** __email_address__::
1812 Administrative contact information for this relay or bridge. This line
1813 can be used to contact you if your relay or bridge is misconfigured or
1814 something else goes wrong. Note that we archive and publish all
1815 descriptors containing these lines and that Google indexes them, so
1816 spammers might also collect them. You may want to obscure the fact
1817 that it's an email address and/or generate a new address for this
1820 ContactInfo **must** be set to a working address if you run more than one
1821 relay or bridge. (Really, everybody running a relay or bridge should set
1825 [[ExitRelay]] **ExitRelay** **0**|**1**|**auto**::
1826 Tells Tor whether to run as an exit relay. If Tor is running as a
1827 non-bridge server, and ExitRelay is set to 1, then Tor allows traffic to
1828 exit according to the ExitPolicy option (or the default ExitPolicy if
1829 none is specified). +
1831 If ExitRelay is set to 0, no traffic is allowed to
1832 exit, and the ExitPolicy option is ignored. +
1834 If ExitRelay is set to "auto", then Tor behaves as if it were set to 1, but
1835 warns the user if this would cause traffic to exit. In a future version,
1836 the default value will be 0. (Default: auto)
1838 [[ExitPolicy]] **ExitPolicy** __policy__,__policy__,__...__::
1839 Set an exit policy for this server. Each policy is of the form
1840 "**accept[6]**|**reject[6]** __ADDR__[/__MASK__][:__PORT__]". If /__MASK__ is
1841 omitted then this policy just applies to the host given. Instead of giving
1842 a host or network you can also use "\*" to denote the universe (0.0.0.0/0
1843 and ::/128), or \*4 to denote all IPv4 addresses, and \*6 to denote all
1845 __PORT__ can be a single port number, an interval of ports
1846 "__FROM_PORT__-__TO_PORT__", or "\*". If __PORT__ is omitted, that means
1849 For example, "accept 18.7.22.69:\*,reject 18.0.0.0/8:\*,accept \*:\*" would
1850 reject any IPv4 traffic destined for MIT except for web.mit.edu, and accept
1851 any other IPv4 or IPv6 traffic. +
1853 Tor also allows IPv6 exit policy entries. For instance, "reject6 [FC00::]/7:\*"
1854 rejects all destinations that share 7 most significant bit prefix with
1855 address FC00::. Respectively, "accept6 [C000::]/3:\*" accepts all destinations
1856 that share 3 most significant bit prefix with address C000::. +
1858 accept6 and reject6 only produce IPv6 exit policy entries. Using an IPv4
1859 address with accept6 or reject6 is ignored and generates a warning.
1860 accept/reject allows either IPv4 or IPv6 addresses. Use \*4 as an IPv4
1861 wildcard address, and \*6 as an IPv6 wildcard address. accept/reject *
1862 expands to matching IPv4 and IPv6 wildcard address rules. +
1864 To specify all IPv4 and IPv6 internal and link-local networks (including
1865 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,
1866 172.16.0.0/12, [::]/8, [FC00::]/7, [FE80::]/10, [FEC0::]/10, [FF00::]/8,
1867 and [::]/127), you can use the "private" alias instead of an address.
1868 ("private" always produces rules for IPv4 and IPv6 addresses, even when
1869 used with accept6/reject6.) +
1871 Private addresses are rejected by default (at the beginning of your exit
1872 policy), along with any configured primary public IPv4 and IPv6 addresses.
1873 These private addresses are rejected unless you set the
1874 ExitPolicyRejectPrivate config option to 0. For example, once you've done
1875 that, you could allow HTTP to 127.0.0.1 and block all other connections to
1876 internal networks with "accept 127.0.0.1:80,reject private:\*", though that
1877 may also allow connections to your own computer that are addressed to its
1878 public (external) IP address. See RFC 1918 and RFC 3330 for more details
1879 about internal and reserved IP address space. See
1880 ExitPolicyRejectLocalInterfaces if you want to block every address on the
1881 relay, even those that aren't advertised in the descriptor. +
1883 This directive can be specified multiple times so you don't have to put it
1886 Policies are considered first to last, and the first match wins. If you
1887 want to allow the same ports on IPv4 and IPv6, write your rules using
1888 accept/reject \*. If you want to allow different ports on IPv4 and IPv6,
1889 write your IPv6 rules using accept6/reject6 \*6, and your IPv4 rules using
1890 accept/reject \*4. If you want to \_replace_ the default exit policy, end
1891 your exit policy with either a reject \*:* or an accept \*:*. Otherwise,
1892 you're \_augmenting_ (prepending to) the default exit policy. +
1894 If you want to use a reduced exit policy rather than the default exit
1895 policy, set "ReducedExitPolicy 1". If you want to _replace_ the default
1896 exit policy with your custom exit policy, end your exit policy with either
1897 a reject *:* or an accept *:*. Otherwise, you’re _augmenting_ (prepending
1898 to) the default or reduced exit policy. +
1900 The default exit policy is:
1914 [[ExitPolicyDefault]] **ExitPolicyDefault**::
1915 Since the default exit policy uses accept/reject *, it applies to both
1916 IPv4 and IPv6 addresses.
1918 [[ExitPolicyRejectPrivate]] **ExitPolicyRejectPrivate** **0**|**1**::
1919 Reject all private (local) networks, along with the relay's advertised
1920 public IPv4 and IPv6 addresses, at the beginning of your exit policy.
1921 See above entry on ExitPolicy.
1924 [[ExitPolicyRejectLocalInterfaces]] **ExitPolicyRejectLocalInterfaces** **0**|**1**::
1925 Reject all IPv4 and IPv6 addresses that the relay knows about, at the
1926 beginning of your exit policy. This includes any OutboundBindAddress, the
1927 bind addresses of any port options, such as ControlPort or DNSPort, and any
1928 public IPv4 and IPv6 addresses on any interface on the relay. (If IPv6Exit
1929 is not set, all IPv6 addresses will be rejected anyway.)
1930 See above entry on ExitPolicy.
1931 This option is off by default, because it lists all public relay IP
1932 addresses in the ExitPolicy, even those relay operators might prefer not
1936 [[ReducedExitPolicy]] **ReducedExitPolicy** **0**|**1**::
1937 If set, use a reduced exit policy rather than the default one. +
1939 The reduced exit policy is an alternative to the default exit policy. It
1940 allows as many Internet services as possible while still blocking the
1941 majority of TCP ports. Currently, the policy allows approximately 65 ports.
1942 This reduces the odds that your node will be used for peer-to-peer
1945 The reduced exit policy is:
2029 [[IPv6Exit]] **IPv6Exit** **0**|**1**::
2030 If set, and we are an exit node, allow clients to use us for IPv6
2031 traffic. (Default: 0)
2033 [[MaxOnionQueueDelay]] **MaxOnionQueueDelay** __NUM__ [**msec**|**second**]::
2034 If we have more onionskins queued for processing than we can process in
2035 this amount of time, reject new ones. (Default: 1750 msec)
2037 [[MyFamily]] **MyFamily** __fingerprint__,__fingerprint__,...::
2038 Declare that this Tor relay is controlled or administered by a group or
2039 organization identical or similar to that of the other relays, defined by
2040 their (possibly $-prefixed) identity fingerprints.
2041 This option can be repeated many times, for
2042 convenience in defining large families: all fingerprints in all MyFamily
2043 lines are merged into one list.
2044 When two relays both declare that they are in the
2045 same \'family', Tor clients will not use them in the same circuit. (Each
2046 relay only needs to list the other servers in its family; it doesn't need to
2047 list itself, but it won't hurt if it does.) Do not list any bridge relay as it would
2048 compromise its concealment. +
2050 When listing a node, it's better to list it by fingerprint than by
2051 nickname: fingerprints are more reliable. +
2053 If you run more than one relay, the MyFamily option on each relay
2054 **must** list all other relays, as described above.
2056 [[Nickname]] **Nickname** __name__::
2057 Set the server's nickname to \'name'. Nicknames must be between 1 and 19
2058 characters inclusive, and must contain only the characters [a-zA-Z0-9].
2060 [[NumCPUs]] **NumCPUs** __num__::
2061 How many processes to use at once for decrypting onionskins and other
2062 parallelizable operations. If this is set to 0, Tor will try to detect
2063 how many CPUs you have, defaulting to 1 if it can't tell. (Default: 0)
2065 [[ORPort]] **ORPort** \['address':]__PORT__|**auto** [_flags_]::
2066 Advertise this port to listen for connections from Tor clients and
2067 servers. This option is required to be a Tor server.
2068 Set it to "auto" to have Tor pick a port for you. Set it to 0 to not
2069 run an ORPort at all. This option can occur more than once. (Default: 0) +
2071 Tor recognizes these flags on each ORPort:
2073 By default, we bind to a port and tell our users about it. If
2074 NoAdvertise is specified, we don't advertise, but listen anyway. This
2075 can be useful if the port everybody will be connecting to (for
2076 example, one that's opened on our firewall) is somewhere else.
2078 By default, we bind to a port and tell our users about it. If
2079 NoListen is specified, we don't bind, but advertise anyway. This
2080 can be useful if something else (for example, a firewall's port
2081 forwarding configuration) is causing connections to reach us.
2083 If the address is absent, or resolves to both an IPv4 and an IPv6
2084 address, only listen to the IPv4 address.
2086 If the address is absent, or resolves to both an IPv4 and an IPv6
2087 address, only listen to the IPv6 address.
2089 [[ORPortFlagsExclusive]]::
2090 For obvious reasons, NoAdvertise and NoListen are mutually exclusive, and
2091 IPv4Only and IPv6Only are mutually exclusive.
2093 [[PortForwarding]] **PortForwarding** **0**|**1**::
2094 Attempt to automatically forward the DirPort and ORPort on a NAT router
2095 connecting this Tor server to the Internet. If set, Tor will try both
2096 NAT-PMP (common on Apple routers) and UPnP (common on routers from other
2097 manufacturers). (Default: 0)
2099 [[PortForwardingHelper]] **PortForwardingHelper** __filename__|__pathname__::
2100 If PortForwarding is set, use this executable to configure the forwarding.
2101 If set to a filename, the system path will be searched for the executable.
2102 If set to a path, only the specified path will be executed.
2103 (Default: tor-fw-helper)
2105 [[PublishServerDescriptor]] **PublishServerDescriptor** **0**|**1**|**v3**|**bridge**,**...**::
2106 This option specifies which descriptors Tor will publish when acting as
2108 choose multiple arguments, separated by commas. +
2110 If this option is set to 0, Tor will not publish its
2111 descriptors to any directories. (This is useful if you're testing
2112 out your server, or if you're using a Tor controller that handles
2113 directory publishing for you.) Otherwise, Tor will publish its
2114 descriptors of all type(s) specified. The default is "1", which
2115 means "if running as a relay or bridge, publish descriptors to the
2116 appropriate authorities". Other possibilities are "v3", meaning
2117 "publish as if you're a relay", and "bridge", meaning "publish as
2118 if you're a bridge".
2120 [[ShutdownWaitLength]] **ShutdownWaitLength** __NUM__::
2121 When we get a SIGINT and we're a server, we begin shutting down:
2122 we close listeners and start refusing new circuits. After **NUM**
2123 seconds, we exit. If we get a second SIGINT, we exit immediately.
2124 (Default: 30 seconds)
2126 [[SSLKeyLifetime]] **SSLKeyLifetime** __N__ **minutes**|**hours**|**days**|**weeks**::
2127 When creating a link certificate for our outermost SSL handshake,
2128 set its lifetime to this amount of time. If set to 0, Tor will choose
2129 some reasonable random defaults. (Default: 0)
2131 [[HeartbeatPeriod]] **HeartbeatPeriod** __N__ **minutes**|**hours**|**days**|**weeks**::
2132 Log a heartbeat message every **HeartbeatPeriod** seconds. This is
2133 a log level __notice__ message, designed to let you know your Tor
2134 server is still alive and doing useful things. Settings this
2135 to 0 will disable the heartbeat. Otherwise, it must be at least 30
2136 minutes. (Default: 6 hours)
2138 [[MainloopStats]] **MainloopStats** **0**|**1**::
2139 Log main loop statistics every **HeartbeatPeriod** seconds. This is a log
2140 level __notice__ message designed to help developers instrumenting Tor's
2141 main event loop. (Default: 0)
2143 [[AccountingMax]] **AccountingMax** __N__ **bytes**|**KBytes**|**MBytes**|**GBytes**|**TBytes**|**KBits**|**MBits**|**GBits**|**TBits**::
2144 Limits the max number of bytes sent and received within a set time period
2145 using a given calculation rule (see: AccountingStart, AccountingRule).
2146 Useful if you need to stay under a specific bandwidth. By default, the
2147 number used for calculation is the max of either the bytes sent or
2148 received. For example, with AccountingMax set to 1 GByte, a server
2149 could send 900 MBytes and receive 800 MBytes and continue running.
2150 It will only hibernate once one of the two reaches 1 GByte. This can
2151 be changed to use the sum of the both bytes received and sent by setting
2152 the AccountingRule option to "sum" (total bandwidth in/out). When the
2153 number of bytes remaining gets low, Tor will stop accepting new connections
2154 and circuits. When the number of bytes is exhausted, Tor will hibernate
2155 until some time in the next accounting period. To prevent all servers
2156 from waking at the same time, Tor will also wait until a random point
2157 in each period before waking up. If you have bandwidth cost issues,
2158 enabling hibernation is preferable to setting a low bandwidth, since
2159 it provides users with a collection of fast servers that are up some
2160 of the time, which is more useful than a set of slow servers that are
2163 [[AccountingRule]] **AccountingRule** **sum**|**max**|**in**|**out**::
2164 How we determine when our AccountingMax has been reached (when we
2165 should hibernate) during a time interval. Set to "max" to calculate
2166 using the higher of either the sent or received bytes (this is the
2167 default functionality). Set to "sum" to calculate using the sent
2168 plus received bytes. Set to "in" to calculate using only the
2169 received bytes. Set to "out" to calculate using only the sent bytes.
2172 [[AccountingStart]] **AccountingStart** **day**|**week**|**month** [__day__] __HH:MM__::
2173 Specify how long accounting periods last. If **month** is given, each
2174 accounting period runs from the time __HH:MM__ on the __dayth__ day of one
2175 month to the same day and time of the next. (The day must be between 1 and
2176 28.) If **week** is given, each accounting period runs from the time __HH:MM__
2177 of the __dayth__ day of one week to the same day and time of the next week,
2178 with Monday as day 1 and Sunday as day 7. If **day** is given, each
2179 accounting period runs from the time __HH:MM__ each day to the same time on
2180 the next day. All times are local, and given in 24-hour time. (Default:
2183 [[RefuseUnknownExits]] **RefuseUnknownExits** **0**|**1**|**auto**::
2184 Prevent nodes that don't appear in the consensus from exiting using this
2185 relay. If the option is 1, we always block exit attempts from such
2186 nodes; if it's 0, we never do, and if the option is "auto", then we do
2187 whatever the authorities suggest in the consensus (and block if the consensus
2188 is quiet on the issue). (Default: auto)
2190 [[ServerDNSResolvConfFile]] **ServerDNSResolvConfFile** __filename__::
2191 Overrides the default DNS configuration with the configuration in
2192 __filename__. The file format is the same as the standard Unix
2193 "**resolv.conf**" file (7). This option, like all other ServerDNS options,
2194 only affects name lookups that your server does on behalf of clients.
2195 (Defaults to use the system DNS configuration.)
2197 [[ServerDNSAllowBrokenConfig]] **ServerDNSAllowBrokenConfig** **0**|**1**::
2198 If this option is false, Tor exits immediately if there are problems
2199 parsing the system DNS configuration or connecting to nameservers.
2200 Otherwise, Tor continues to periodically retry the system nameservers until
2201 it eventually succeeds. (Default: 1)
2203 [[ServerDNSSearchDomains]] **ServerDNSSearchDomains** **0**|**1**::
2204 If set to 1, then we will search for addresses in the local search domain.
2205 For example, if this system is configured to believe it is in
2206 "example.com", and a client tries to connect to "www", the client will be
2207 connected to "www.example.com". This option only affects name lookups that
2208 your server does on behalf of clients. (Default: 0)
2210 [[ServerDNSDetectHijacking]] **ServerDNSDetectHijacking** **0**|**1**::
2211 When this option is set to 1, we will test periodically to determine
2212 whether our local nameservers have been configured to hijack failing DNS
2213 requests (usually to an advertising site). If they are, we will attempt to
2214 correct this. This option only affects name lookups that your server does
2215 on behalf of clients. (Default: 1)
2217 [[ServerDNSTestAddresses]] **ServerDNSTestAddresses** __hostname__,__hostname__,__...__::
2218 When we're detecting DNS hijacking, make sure that these __valid__ addresses
2219 aren't getting redirected. If they are, then our DNS is completely useless,
2220 and we'll reset our exit policy to "reject \*:*". This option only affects
2221 name lookups that your server does on behalf of clients. (Default:
2222 "www.google.com, www.mit.edu, www.yahoo.com, www.slashdot.org")
2224 [[ServerDNSAllowNonRFC953Hostnames]] **ServerDNSAllowNonRFC953Hostnames** **0**|**1**::
2225 When this option is disabled, Tor does not try to resolve hostnames
2226 containing illegal characters (like @ and :) rather than sending them to an
2227 exit node to be resolved. This helps trap accidental attempts to resolve
2228 URLs and so on. This option only affects name lookups that your server does
2229 on behalf of clients. (Default: 0)
2231 [[BridgeRecordUsageByCountry]] **BridgeRecordUsageByCountry** **0**|**1**::
2232 When this option is enabled and BridgeRelay is also enabled, and we have
2233 GeoIP data, Tor keeps a per-country count of how many client
2234 addresses have contacted it so that it can help the bridge authority guess
2235 which countries have blocked access to it. (Default: 1)
2237 [[ServerDNSRandomizeCase]] **ServerDNSRandomizeCase** **0**|**1**::
2238 When this option is set, Tor sets the case of each character randomly in
2239 outgoing DNS requests, and makes sure that the case matches in DNS replies.
2240 This so-called "0x20 hack" helps resist some types of DNS poisoning attack.
2241 For more information, see "Increased DNS Forgery Resistance through
2242 0x20-Bit Encoding". This option only affects name lookups that your server
2243 does on behalf of clients. (Default: 1)
2245 [[GeoIPFile]] **GeoIPFile** __filename__::
2246 A filename containing IPv4 GeoIP data, for use with by-country statistics.
2248 [[GeoIPv6File]] **GeoIPv6File** __filename__::
2249 A filename containing IPv6 GeoIP data, for use with by-country statistics.
2251 [[CellStatistics]] **CellStatistics** **0**|**1**::
2253 When this option is enabled, Tor collects statistics about cell
2254 processing (i.e. mean time a cell is spending in a queue, mean
2255 number of cells in a queue and mean number of processed cells per
2256 circuit) and writes them into disk every 24 hours. Onion router
2257 operators may use the statistics for performance monitoring.
2258 If ExtraInfoStatistics is enabled, it will published as part of
2259 extra-info document. (Default: 0)
2261 [[PaddingStatistics]] **PaddingStatistics** **0**|**1**::
2263 When this option is enabled, Tor collects statistics for padding cells
2264 sent and received by this relay, in addition to total cell counts.
2265 These statistics are rounded, and omitted if traffic is low. This
2266 information is important for load balancing decisions related to padding.
2269 [[DirReqStatistics]] **DirReqStatistics** **0**|**1**::
2270 Relays and bridges only.
2271 When this option is enabled, a Tor directory writes statistics on the
2272 number and response time of network status requests to disk every 24
2273 hours. Enables relay and bridge operators to monitor how much their
2274 server is being used by clients to learn about Tor network.
2275 If ExtraInfoStatistics is enabled, it will published as part of
2276 extra-info document. (Default: 1)
2278 [[EntryStatistics]] **EntryStatistics** **0**|**1**::
2280 When this option is enabled, Tor writes statistics on the number of
2281 directly connecting clients to disk every 24 hours. Enables relay
2282 operators to monitor how much inbound traffic that originates from
2283 Tor clients passes through their server to go further down the
2284 Tor network. If ExtraInfoStatistics is enabled, it will be published
2285 as part of extra-info document. (Default: 0)
2287 [[ExitPortStatistics]] **ExitPortStatistics** **0**|**1**::
2289 When this option is enabled, Tor writes statistics on the number of
2290 relayed bytes and opened stream per exit port to disk every 24 hours.
2291 Enables exit relay operators to measure and monitor amounts of traffic
2292 that leaves Tor network through their exit node. If ExtraInfoStatistics
2293 is enabled, it will be published as part of extra-info document.
2296 [[ConnDirectionStatistics]] **ConnDirectionStatistics** **0**|**1**::
2298 When this option is enabled, Tor writes statistics on the amounts of
2299 traffic it passes between itself and other relays to disk every 24
2300 hours. Enables relay operators to monitor how much their relay is
2301 being used as middle node in the circuit. If ExtraInfoStatistics is
2302 enabled, it will be published as part of extra-info document.
2305 [[HiddenServiceStatistics]] **HiddenServiceStatistics** **0**|**1**::
2307 When this option is enabled, a Tor relay writes obfuscated
2308 statistics on its role as hidden-service directory, introduction
2309 point, or rendezvous point to disk every 24 hours. If
2310 ExtraInfoStatistics is also enabled, these statistics are further
2311 published to the directory authorities. (Default: 1)
2313 [[ExtraInfoStatistics]] **ExtraInfoStatistics** **0**|**1**::
2314 When this option is enabled, Tor includes previously gathered statistics in
2315 its extra-info documents that it uploads to the directory authorities.
2318 [[ExtendAllowPrivateAddresses]] **ExtendAllowPrivateAddresses** **0**|**1**::
2319 When this option is enabled, Tor will connect to relays on localhost,
2320 RFC1918 addresses, and so on. In particular, Tor will make direct OR
2321 connections, and Tor routers allow EXTEND requests, to these private
2322 addresses. (Tor will always allow connections to bridges, proxies, and
2323 pluggable transports configured on private addresses.) Enabling this
2324 option can create security issues; you should probably leave it off.
2327 [[MaxMemInQueues]] **MaxMemInQueues** __N__ **bytes**|**KB**|**MB**|**GB**::
2328 This option configures a threshold above which Tor will assume that it
2329 needs to stop queueing or buffering data because it's about to run out of
2330 memory. If it hits this threshold, it will begin killing circuits until
2331 it has recovered at least 10% of this memory. Do not set this option too
2332 low, or your relay may be unreliable under load. This option only
2333 affects some queues, so the actual process size will be larger than
2334 this. If this option is set to 0, Tor will try to pick a reasonable
2335 default based on your system's physical memory. (Default: 0)
2337 [[DisableOOSCheck]] **DisableOOSCheck** **0**|**1**::
2338 This option disables the code that closes connections when Tor notices
2339 that it is running low on sockets. Right now, it is on by default,
2340 since the existing out-of-sockets mechanism tends to kill OR connections
2341 more than it should. (Default: 1)
2343 [[SigningKeyLifetime]] **SigningKeyLifetime** __N__ **days**|**weeks**|**months**::
2344 For how long should each Ed25519 signing key be valid? Tor uses a
2345 permanent master identity key that can be kept offline, and periodically
2346 generates new "signing" keys that it uses online. This option
2347 configures their lifetime.
2350 [[OfflineMasterKey]] **OfflineMasterKey** **0**|**1**::
2351 If non-zero, the Tor relay will never generate or load its master secret
2352 key. Instead, you'll have to use "tor --keygen" to manage the permanent
2353 ed25519 master identity key, as well as the corresponding temporary
2354 signing keys and certificates. (Default: 0)
2356 [[KeyDirectory]] **KeyDirectory** __DIR__::
2357 Store secret keys in DIR. Can not be changed while tor is
2359 (Default: the "keys" subdirectory of DataDirectory.)
2361 [[KeyDirectoryGroupReadable]] **KeyDirectoryGroupReadable** **0**|**1**::
2362 If this option is set to 0, don't allow the filesystem group to read the
2363 KeywDirectory. If the option is set to 1, make the KeyDirectory readable
2364 by the default GID. (Default: 0)
2367 DIRECTORY SERVER OPTIONS
2368 ------------------------
2370 The following options are useful only for directory servers. (Relays with
2371 enough bandwidth automatically become directory servers; see DirCache for
2374 [[DirPortFrontPage]] **DirPortFrontPage** __FILENAME__::
2375 When this option is set, it takes an HTML file and publishes it as "/" on
2376 the DirPort. Now relay operators can provide a disclaimer without needing
2377 to set up a separate webserver. There's a sample disclaimer in
2378 contrib/operator-tools/tor-exit-notice.html.
2380 [[DirPort]] **DirPort** \['address':]__PORT__|**auto** [_flags_]::
2381 If this option is nonzero, advertise the directory service on this port.
2382 Set it to "auto" to have Tor pick a port for you. This option can occur
2383 more than once, but only one advertised DirPort is supported: all
2384 but one DirPort must have the **NoAdvertise** flag set. (Default: 0) +
2386 The same flags are supported here as are supported by ORPort.
2388 [[DirPolicy]] **DirPolicy** __policy__,__policy__,__...__::
2389 Set an entrance policy for this server, to limit who can connect to the
2390 directory ports. The policies have the same form as exit policies above,
2391 except that port specifiers are ignored. Any address not matched by
2392 some entry in the policy is accepted.
2394 [[DirCache]] **DirCache** **0**|**1**::
2395 When this option is set, Tor caches all current directory documents and
2396 accepts client requests for them. Setting DirPort is not required for this,
2397 because clients connect via the ORPort by default. Setting either DirPort
2398 or BridgeRelay and setting DirCache to 0 is not supported. (Default: 1)
2400 [[MaxConsensusAgeForDiffs]] **MaxConsensusAgeForDiffs** __N__ **minutes**|**hours**|**days**|**weeks**::
2401 When this option is nonzero, Tor caches will not try to generate
2402 consensus diffs for any consensus older than this amount of time.
2403 If this option is set to zero, Tor will pick a reasonable default from
2404 the current networkstatus document. You should not set this
2405 option unless your cache is severely low on disk space or CPU.
2406 If you need to set it, keeping it above 3 or 4 hours will help clients
2407 much more than setting it to zero.
2411 DIRECTORY AUTHORITY SERVER OPTIONS
2412 ----------------------------------
2414 The following options enable operation as a directory authority, and
2415 control how Tor behaves as a directory authority. You should not need
2416 to adjust any of them if you're running a regular relay or exit server
2417 on the public Tor network.
2419 [[AuthoritativeDirectory]] **AuthoritativeDirectory** **0**|**1**::
2420 When this option is set to 1, Tor operates as an authoritative directory
2421 server. Instead of caching the directory, it generates its own list of
2422 good servers, signs it, and sends that to the clients. Unless the clients
2423 already have you listed as a trusted directory, you probably do not want
2426 [[V3AuthoritativeDirectory]] **V3AuthoritativeDirectory** **0**|**1**::
2427 When this option is set in addition to **AuthoritativeDirectory**, Tor
2428 generates version 3 network statuses and serves descriptors, etc as
2429 described in dir-spec.txt file of https://spec.torproject.org/[torspec]
2430 (for Tor clients and servers running at least 0.2.0.x).
2432 [[VersioningAuthoritativeDirectory]] **VersioningAuthoritativeDirectory** **0**|**1**::
2433 When this option is set to 1, Tor adds information on which versions of
2434 Tor are still believed safe for use to the published directory. Each
2435 version 1 authority is automatically a versioning authority; version 2
2436 authorities provide this service optionally. See **RecommendedVersions**,
2437 **RecommendedClientVersions**, and **RecommendedServerVersions**.
2439 [[RecommendedVersions]] **RecommendedVersions** __STRING__::
2440 STRING is a comma-separated list of Tor versions currently believed to be
2441 safe. The list is included in each directory, and nodes which pull down the
2442 directory learn whether they need to upgrade. This option can appear
2443 multiple times: the values from multiple lines are spliced together. When
2444 this is set then **VersioningAuthoritativeDirectory** should be set too.
2446 [[RecommendedPackages]] **RecommendedPackages** __PACKAGENAME__ __VERSION__ __URL__ __DIGESTTYPE__**=**__DIGEST__ ::
2447 Adds "package" line to the directory authority's vote. This information
2448 is used to vote on the correct URL and digest for the released versions
2449 of different Tor-related packages, so that the consensus can certify
2450 them. This line may appear any number of times.
2452 [[RecommendedClientVersions]] **RecommendedClientVersions** __STRING__::
2453 STRING is a comma-separated list of Tor versions currently believed to be
2454 safe for clients to use. This information is included in version 2
2455 directories. If this is not set then the value of **RecommendedVersions**
2456 is used. When this is set then **VersioningAuthoritativeDirectory** should
2459 [[BridgeAuthoritativeDir]] **BridgeAuthoritativeDir** **0**|**1**::
2460 When this option is set in addition to **AuthoritativeDirectory**, Tor
2461 accepts and serves server descriptors, but it caches and serves the main
2462 networkstatus documents rather than generating its own. (Default: 0)
2464 [[MinUptimeHidServDirectoryV2]] **MinUptimeHidServDirectoryV2** __N__ **seconds**|**minutes**|**hours**|**days**|**weeks**::
2465 Minimum uptime of a v2 hidden service directory to be accepted as such by
2466 authoritative directories. (Default: 25 hours)
2468 [[RecommendedServerVersions]] **RecommendedServerVersions** __STRING__::
2469 STRING is a comma-separated list of Tor versions currently believed to be
2470 safe for servers to use. This information is included in version 2
2471 directories. If this is not set then the value of **RecommendedVersions**
2472 is used. When this is set then **VersioningAuthoritativeDirectory** should
2475 [[ConsensusParams]] **ConsensusParams** __STRING__::
2476 STRING is a space-separated list of key=value pairs that Tor will include
2477 in the "params" line of its networkstatus vote.
2479 [[DirAllowPrivateAddresses]] **DirAllowPrivateAddresses** **0**|**1**::
2480 If set to 1, Tor will accept server descriptors with arbitrary "Address"
2481 elements. Otherwise, if the address is not an IP address or is a private IP
2482 address, it will reject the server descriptor. Additionally, Tor
2483 will allow exit policies for private networks to fulfill Exit flag
2484 requirements. (Default: 0)
2486 [[AuthDirBadExit]] **AuthDirBadExit** __AddressPattern...__::
2487 Authoritative directories only. A set of address patterns for servers that
2488 will be listed as bad exits in any network status document this authority
2489 publishes, if **AuthDirListBadExits** is set. +
2491 (The address pattern syntax here and in the options below
2492 is the same as for exit policies, except that you don't need to say
2493 "accept" or "reject", and ports are not needed.)
2495 [[AuthDirInvalid]] **AuthDirInvalid** __AddressPattern...__::
2496 Authoritative directories only. A set of address patterns for servers that
2497 will never be listed as "valid" in any network status document that this
2498 authority publishes.
2500 [[AuthDirReject]] **AuthDirReject** __AddressPattern__...::
2501 Authoritative directories only. A set of address patterns for servers that
2502 will never be listed at all in any network status document that this
2503 authority publishes, or accepted as an OR address in any descriptor
2504 submitted for publication by this authority.
2506 [[AuthDirBadExitCCs]] **AuthDirBadExitCCs** __CC__,... +
2508 [[AuthDirInvalidCCs]] **AuthDirInvalidCCs** __CC__,... +
2510 [[AuthDirRejectCCs]] **AuthDirRejectCCs** __CC__,...::
2511 Authoritative directories only. These options contain a comma-separated
2512 list of country codes such that any server in one of those country codes
2513 will be marked as a bad exit/invalid for use, or rejected
2516 [[AuthDirListBadExits]] **AuthDirListBadExits** **0**|**1**::
2517 Authoritative directories only. If set to 1, this directory has some
2518 opinion about which nodes are unsuitable as exit nodes. (Do not set this to
2519 1 unless you plan to list non-functioning exits as bad; otherwise, you are
2520 effectively voting in favor of every declared exit as an exit.)
2522 [[AuthDirMaxServersPerAddr]] **AuthDirMaxServersPerAddr** __NUM__::
2523 Authoritative directories only. The maximum number of servers that we will
2524 list as acceptable on a single IP address. Set this to "0" for "no limit".
2527 [[AuthDirFastGuarantee]] **AuthDirFastGuarantee** __N__ **bytes**|**KBytes**|**MBytes**|**GBytes**|**TBytes**|**KBits**|**MBits**|**GBits**|**TBits**::
2528 Authoritative directories only. If non-zero, always vote the
2529 Fast flag for any relay advertising this amount of capacity or
2530 more. (Default: 100 KBytes)
2532 [[AuthDirGuardBWGuarantee]] **AuthDirGuardBWGuarantee** __N__ **bytes**|**KBytes**|**MBytes**|**GBytes**|**TBytes**|**KBits**|**MBits**|**GBits**|**TBits**::
2533 Authoritative directories only. If non-zero, this advertised capacity
2534 or more is always sufficient to satisfy the bandwidth requirement
2535 for the Guard flag. (Default: 2 MBytes)
2537 [[AuthDirPinKeys]] **AuthDirPinKeys** **0**|**1**::
2538 Authoritative directories only. If non-zero, do not allow any relay to
2539 publish a descriptor if any other relay has reserved its <Ed25519,RSA>
2540 identity keypair. In all cases, Tor records every keypair it accepts
2541 in a journal if it is new, or if it differs from the most recently
2542 accepted pinning for one of the keys it contains. (Default: 1)
2544 [[AuthDirSharedRandomness]] **AuthDirSharedRandomness** **0**|**1**::
2545 Authoritative directories only. Switch for the shared random protocol.
2546 If zero, the authority won't participate in the protocol. If non-zero
2547 (default), the flag "shared-rand-participate" is added to the authority
2548 vote indicating participation in the protocol. (Default: 1)
2550 [[AuthDirTestEd25519LinkKeys]] **AuthDirTestEd25519LinkKeys** **0**|**1**::
2551 Authoritative directories only. If this option is set to 0, then we treat
2552 relays as "Running" if their RSA key is correct when we probe them,
2553 regardless of their Ed25519 key. We should only ever set this option to 0
2554 if there is some major bug in Ed25519 link authentication that causes us
2555 to label all the relays as not Running. (Default: 1)
2557 [[BridgePassword]] **BridgePassword** __Password__::
2558 If set, contains an HTTP authenticator that tells a bridge authority to
2559 serve all requested bridge information. Used by the (only partially
2560 implemented) "bridge community" design, where a community of bridge
2561 relay operators all use an alternate bridge directory authority,
2562 and their target user audience can periodically fetch the list of
2563 available community bridges to stay up-to-date. (Default: not set)
2565 [[V3AuthVotingInterval]] **V3AuthVotingInterval** __N__ **minutes**|**hours**::
2566 V3 authoritative directories only. Configures the server's preferred voting
2567 interval. Note that voting will __actually__ happen at an interval chosen
2568 by consensus from all the authorities' preferred intervals. This time
2569 SHOULD divide evenly into a day. (Default: 1 hour)
2571 [[V3AuthVoteDelay]] **V3AuthVoteDelay** __N__ **minutes**|**hours**::
2572 V3 authoritative directories only. Configures the server's preferred delay
2573 between publishing its vote and assuming it has all the votes from all the
2574 other authorities. Note that the actual time used is not the server's
2575 preferred time, but the consensus of all preferences. (Default: 5 minutes)
2577 [[V3AuthDistDelay]] **V3AuthDistDelay** __N__ **minutes**|**hours**::
2578 V3 authoritative directories only. Configures the server's preferred delay
2579 between publishing its consensus and signature and assuming it has all the
2580 signatures from all the other authorities. Note that the actual time used
2581 is not the server's preferred time, but the consensus of all preferences.
2582 (Default: 5 minutes)
2584 [[V3AuthNIntervalsValid]] **V3AuthNIntervalsValid** __NUM__::
2585 V3 authoritative directories only. Configures the number of VotingIntervals
2586 for which each consensus should be valid for. Choosing high numbers
2587 increases network partitioning risks; choosing low numbers increases
2588 directory traffic. Note that the actual number of intervals used is not the
2589 server's preferred number, but the consensus of all preferences. Must be at
2590 least 2. (Default: 3)
2592 [[V3BandwidthsFile]] **V3BandwidthsFile** __FILENAME__::
2593 V3 authoritative directories only. Configures the location of the
2594 bandwidth-authority generated file storing information on relays' measured
2595 bandwidth capacities. (Default: unset)
2597 [[V3AuthUseLegacyKey]] **V3AuthUseLegacyKey** **0**|**1**::
2598 If set, the directory authority will sign consensuses not only with its
2599 own signing key, but also with a "legacy" key and certificate with a
2600 different identity. This feature is used to migrate directory authority
2601 keys in the event of a compromise. (Default: 0)
2603 [[RephistTrackTime]] **RephistTrackTime** __N__ **seconds**|**minutes**|**hours**|**days**|**weeks**::
2604 Tells an authority, or other node tracking node reliability and history,
2605 that fine-grained information about nodes can be discarded when it hasn't
2606 changed for a given amount of time. (Default: 24 hours)
2608 [[AuthDirHasIPv6Connectivity]] **AuthDirHasIPv6Connectivity** **0**|**1**::
2609 Authoritative directories only. When set to 0, OR ports with an
2610 IPv6 address are not included in the authority's votes. When set to 1,
2611 IPv6 OR ports are tested for reachability like IPv4 OR ports. If the
2612 reachability test succeeds, the authority votes for the IPv6 ORPort, and
2613 votes Running for the relay. If the reachability test fails, the authority
2614 does not vote for the IPv6 ORPort, and does not vote Running (Default: 0) +
2616 The content of the consensus depends on the number of voting authorities
2617 that set AuthDirHasIPv6Connectivity:
2619 If no authorities set AuthDirHasIPv6Connectivity 1, there will be no
2620 IPv6 ORPorts in the consensus.
2622 If a minority of authorities set AuthDirHasIPv6Connectivity 1,
2623 unreachable IPv6 ORPorts will be removed from the consensus. But the
2624 majority of IPv4-only authorities will still vote the relay as Running.
2625 Reachable IPv6 ORPort lines will be included in the consensus
2627 If a majority of voting authorities set AuthDirHasIPv6Connectivity 1,
2628 relays with unreachable IPv6 ORPorts will not be listed as Running.
2629 Reachable IPv6 ORPort lines will be included in the consensus
2630 (To ensure that any valid majority will vote relays with unreachable
2631 IPv6 ORPorts not Running, 75% of authorities must set
2632 AuthDirHasIPv6Connectivity 1.)
2634 [[MinMeasuredBWsForAuthToIgnoreAdvertised]] **MinMeasuredBWsForAuthToIgnoreAdvertised** __N__::
2635 A total value, in abstract bandwidth units, describing how much
2636 measured total bandwidth an authority should have observed on the network
2637 before it will treat advertised bandwidths as wholly
2638 unreliable. (Default: 500)
2640 HIDDEN SERVICE OPTIONS
2641 ----------------------
2643 The following options are used to configure a hidden service.
2645 [[HiddenServiceDir]] **HiddenServiceDir** __DIRECTORY__::
2646 Store data files for a hidden service in DIRECTORY. Every hidden service
2647 must have a separate directory. You may use this option multiple times to
2648 specify multiple services. If DIRECTORY does not exist, Tor will create it.
2649 (Note: in current versions of Tor, if DIRECTORY is a relative path,
2650 it will be relative to the current
2651 working directory of Tor instance, not to its DataDirectory. Do not
2652 rely on this behavior; it is not guaranteed to remain the same in future
2655 [[HiddenServicePort]] **HiddenServicePort** __VIRTPORT__ [__TARGET__]::
2656 Configure a virtual port VIRTPORT for a hidden service. You may use this
2657 option multiple times; each time applies to the service using the most
2658 recent HiddenServiceDir. By default, this option maps the virtual port to
2659 the same port on 127.0.0.1 over TCP. You may override the target port,
2660 address, or both by specifying a target of addr, port, addr:port, or
2661 **unix:**__path__. (You can specify an IPv6 target as [addr]:port. Unix
2662 paths may be quoted, and may use standard C escapes.)
2663 You may also have multiple lines with the same VIRTPORT: when a user
2664 connects to that VIRTPORT, one of the TARGETs from those lines will be
2667 [[PublishHidServDescriptors]] **PublishHidServDescriptors** **0**|**1**::
2668 If set to 0, Tor will run any hidden services you configure, but it won't
2669 advertise them to the rendezvous directory. This option is only useful if
2670 you're using a Tor controller that handles hidserv publishing for you.
2673 [[HiddenServiceVersion]] **HiddenServiceVersion** **2**|**3**::
2674 A list of rendezvous service descriptor versions to publish for the hidden
2675 service. Currently, versions 2 and 3 are supported. (Default: 2)
2677 [[HiddenServiceAuthorizeClient]] **HiddenServiceAuthorizeClient** __auth-type__ __client-name__,__client-name__,__...__::
2678 If configured, the hidden service is accessible for authorized clients
2679 only. The auth-type can either be \'basic' for a general-purpose
2680 authorization protocol or \'stealth' for a less scalable protocol that also
2681 hides service activity from unauthorized clients. Only clients that are
2682 listed here are authorized to access the hidden service. Valid client names
2683 are 1 to 16 characters long and only use characters in A-Za-z0-9+-_ (no
2684 spaces). If this option is set, the hidden service is not accessible for
2685 clients without authorization any more. Generated authorization data can be
2686 found in the hostname file. Clients need to put this authorization data in
2687 their configuration file using **HidServAuth**.
2689 [[HiddenServiceAllowUnknownPorts]] **HiddenServiceAllowUnknownPorts** **0**|**1**::
2690 If set to 1, then connections to unrecognized ports do not cause the
2691 current hidden service to close rendezvous circuits. (Setting this to 0 is
2692 not an authorization mechanism; it is instead meant to be a mild
2693 inconvenience to port-scanners.) (Default: 0)
2695 [[HiddenServiceMaxStreams]] **HiddenServiceMaxStreams** __N__::
2696 The maximum number of simultaneous streams (connections) per rendezvous
2697 circuit. The maximum value allowed is 65535. (Setting this to 0 will allow
2698 an unlimited number of simultanous streams.) (Default: 0)
2700 [[HiddenServiceMaxStreamsCloseCircuit]] **HiddenServiceMaxStreamsCloseCircuit** **0**|**1**::
2701 If set to 1, then exceeding **HiddenServiceMaxStreams** will cause the
2702 offending rendezvous circuit to be torn down, as opposed to stream creation
2703 requests that exceed the limit being silently ignored. (Default: 0)
2705 [[RendPostPeriod]] **RendPostPeriod** __N__ **seconds**|**minutes**|**hours**|**days**|**weeks**::
2706 Every time the specified period elapses, Tor uploads any rendezvous
2707 service descriptors to the directory servers. This information is also
2708 uploaded whenever it changes. Minimum value allowed is 10 minutes and
2709 maximum is 3.5 days. (Default: 1 hour)
2711 [[HiddenServiceDirGroupReadable]] **HiddenServiceDirGroupReadable** **0**|**1**::
2712 If this option is set to 1, allow the filesystem group to read the
2713 hidden service directory and hostname file. If the option is set to 0,
2714 only owner is able to read the hidden service directory. (Default: 0)
2715 Has no effect on Windows.
2717 [[HiddenServiceNumIntroductionPoints]] **HiddenServiceNumIntroductionPoints** __NUM__::
2718 Number of introduction points the hidden service will have. You can't
2719 have more than 10 for v2 service and 20 for v3. (Default: 3)
2721 [[HiddenServiceSingleHopMode]] **HiddenServiceSingleHopMode** **0**|**1**::
2722 **Experimental - Non Anonymous** Hidden Services on a tor instance in
2723 HiddenServiceSingleHopMode make one-hop (direct) circuits between the onion
2724 service server, and the introduction and rendezvous points. (Onion service
2725 descriptors are still posted using 3-hop paths, to avoid onion service
2726 directories blocking the service.)
2727 This option makes every hidden service instance hosted by a tor instance a
2728 Single Onion Service. One-hop circuits make Single Onion servers easily
2729 locatable, but clients remain location-anonymous. However, the fact that a
2730 client is accessing a Single Onion rather than a Hidden Service may be
2731 statistically distinguishable. +
2733 **WARNING:** Once a hidden service directory has been used by a tor
2734 instance in HiddenServiceSingleHopMode, it can **NEVER** be used again for
2735 a hidden service. It is best practice to create a new hidden service
2736 directory, key, and address for each new Single Onion Service and Hidden
2737 Service. It is not possible to run Single Onion Services and Hidden
2738 Services from the same tor instance: they should be run on different
2739 servers with different IP addresses. +
2741 HiddenServiceSingleHopMode requires HiddenServiceNonAnonymousMode to be set
2742 to 1. Since a Single Onion service is non-anonymous, you can not configure
2743 a SOCKSPort on a tor instance that is running in
2744 **HiddenServiceSingleHopMode**. Can not be changed while tor is running.
2747 [[HiddenServiceNonAnonymousMode]] **HiddenServiceNonAnonymousMode** **0**|**1**::
2748 Makes hidden services non-anonymous on this tor instance. Allows the
2749 non-anonymous HiddenServiceSingleHopMode. Enables direct connections in the
2750 server-side hidden service protocol. If you are using this option,
2751 you need to disable all client-side services on your Tor instance,
2752 including setting SOCKSPort to "0". Can not be changed while tor is
2753 running. (Default: 0)
2755 DENIAL OF SERVICE MITIGATION OPTIONS
2756 ------------------------------------
2758 The following options are useful only for a public relay. They control the
2759 Denial of Service mitigation subsystem.
2761 [[DoSCircuitCreationEnabled]] **DoSCircuitCreationEnabled** **0**|**1**|**auto**::
2763 Enable circuit creation DoS mitigation. If enabled, tor will cache client
2764 IPs along with statistics in order to detect circuit DoS attacks. If an
2765 address is positively identified, tor will activate defenses against the
2766 address. See the DoSCircuitCreationDefenseType option for more details.
2767 This is a client to relay detection only. "auto" means use the consensus
2771 [[DoSCircuitCreationMinConnections]] **DoSCircuitCreationMinConnections** __NUM__::
2773 Minimum threshold of concurrent connections before a client address can be
2774 flagged as executing a circuit creation DoS. In other words, once a client
2775 address reaches the circuit rate and has a minimum of NUM concurrent
2776 connections, a detection is positive. "0" means use the consensus
2780 [[DoSCircuitCreationRate]] **DoSCircuitCreationRate** __NUM__::
2782 The allowed circuit creation rate per second applied per client IP
2783 address. If this option is 0, it obeys a consensus parameter. (Default: 0)
2785 [[DoSCircuitCreationBurst]] **DoSCircuitCreationBurst** __NUM__::
2787 The allowed circuit creation burst per client IP address. If the circuit
2788 rate and the burst are reached, a client is marked as executing a circuit
2789 creation DoS. "0" means use the consensus parameter.
2792 [[DoSCircuitCreationDefenseType]] **DoSCircuitCreationDefenseType** __NUM__::
2794 This is the type of defense applied to a detected client address. The
2795 possible values are:
2798 2: Refuse circuit creation for the DoSCircuitCreationDefenseTimePeriod period of time.
2800 "0" means use the consensus parameter.
2803 [[DoSCircuitCreationDefenseTimePeriod]] **DoSCircuitCreationDefenseTimePeriod** __NUM__::
2805 The base time period that the DoS defense is activated for. The actual
2806 value is selected randomly for each activation from NUM+1 to 3/2 * NUM.
2807 "0" means use the consensus parameter.
2810 [[DoSConnectionEnabled]] **DoSConnectionEnabled** **0**|**1**|**auto**::
2812 Enable the connection DoS mitigation. For client address only, this allows
2813 tor to mitigate against large number of concurrent connections made by a
2814 single IP address. "auto" means use the consensus parameter.
2817 [[DoSConnectionMaxConcurrentCount]] **DoSConnectionMaxConcurrentCount** __NUM__::
2819 The maximum threshold of concurrent connection from a client IP address.
2820 Above this limit, a defense selected by DoSConnectionDefenseType is
2821 applied. "0" means use the consensus parameter.
2824 [[DoSConnectionDefenseType]] **DoSConnectionDefenseType** __NUM__::
2826 This is the type of defense applied to a detected client address for the
2827 connection mitigation. The possible values are:
2830 2: Immediately close new connections.
2832 "0" means use the consensus parameter.
2835 [[DoSRefuseSingleHopClientRendezvous]] **DoSRefuseSingleHopClientRendezvous** **0**|**1**|**auto**::
2837 Refuse establishment of rendezvous points for single hop clients. In other
2838 words, if a client directly connects to the relay and sends an
2839 ESTABLISH_RENDEZVOUS cell, it is silently dropped. "auto" means use the
2840 consensus parameter.
2843 TESTING NETWORK OPTIONS
2844 -----------------------
2846 The following options are used for running a testing Tor network.
2848 [[TestingTorNetwork]] **TestingTorNetwork** **0**|**1**::
2849 If set to 1, Tor adjusts default values of the configuration options below,
2850 so that it is easier to set up a testing Tor network. May only be set if
2851 non-default set of DirAuthorities is set. Cannot be unset while Tor is
2855 ServerDNSAllowBrokenConfig 1
2856 DirAllowPrivateAddresses 1
2857 EnforceDistinctSubnets 0
2859 AuthDirMaxServersPerAddr 0
2860 AuthDirMaxServersPerAuthAddr 0
2861 ClientBootstrapConsensusAuthorityDownloadSchedule 0, 2,
2862 4 (for 40 seconds), 8, 16, 32, 60
2863 ClientBootstrapConsensusFallbackDownloadSchedule 0, 1,
2864 4 (for 40 seconds), 8, 16, 32, 60
2865 ClientBootstrapConsensusAuthorityOnlyDownloadSchedule 0, 1,
2866 4 (for 40 seconds), 8, 16, 32, 60
2867 ClientBootstrapConsensusMaxDownloadTries 80
2868 ClientBootstrapConsensusAuthorityOnlyMaxDownloadTries 80
2869 ClientDNSRejectInternalAddresses 0
2870 ClientRejectInternalAddresses 0
2871 CountPrivateBandwidth 1
2872 ExitPolicyRejectPrivate 0
2873 ExtendAllowPrivateAddresses 1
2874 V3AuthVotingInterval 5 minutes
2875 V3AuthVoteDelay 20 seconds
2876 V3AuthDistDelay 20 seconds
2877 MinUptimeHidServDirectoryV2 0 seconds
2878 TestingV3AuthInitialVotingInterval 5 minutes
2879 TestingV3AuthInitialVoteDelay 20 seconds
2880 TestingV3AuthInitialDistDelay 20 seconds
2881 TestingAuthDirTimeToLearnReachability 0 minutes
2882 TestingEstimatedDescriptorPropagationTime 0 minutes
2883 TestingServerDownloadSchedule 0, 0, 0, 5, 10, 15, 20, 30, 60
2884 TestingClientDownloadSchedule 0, 0, 5, 10, 15, 20, 30, 60
2885 TestingServerConsensusDownloadSchedule 0, 0, 5, 10, 15, 20, 30, 60
2886 TestingClientConsensusDownloadSchedule 0, 0, 5, 10, 15, 20, 30, 60
2887 TestingBridgeDownloadSchedule 10, 30, 60
2888 TestingBridgeBootstrapDownloadSchedule 0, 0, 5, 10, 15, 20, 30, 60
2889 TestingClientMaxIntervalWithoutRequest 5 seconds
2890 TestingDirConnectionMaxStall 30 seconds
2891 TestingConsensusMaxDownloadTries 80
2892 TestingDescriptorMaxDownloadTries 80
2893 TestingMicrodescMaxDownloadTries 80
2894 TestingCertMaxDownloadTries 80
2895 TestingEnableConnBwEvent 1
2896 TestingEnableCellStatsEvent 1
2897 TestingEnableTbEmptyEvent 1
2899 [[TestingV3AuthInitialVotingInterval]] **TestingV3AuthInitialVotingInterval** __N__ **minutes**|**hours**::
2900 Like V3AuthVotingInterval, but for initial voting interval before the first
2901 consensus has been created. Changing this requires that
2902 **TestingTorNetwork** is set. (Default: 30 minutes)
2904 [[TestingV3AuthInitialVoteDelay]] **TestingV3AuthInitialVoteDelay** __N__ **minutes**|**hours**::
2905 Like V3AuthVoteDelay, but for initial voting interval before
2906 the first consensus has been created. Changing this requires that
2907 **TestingTorNetwork** is set. (Default: 5 minutes)
2909 [[TestingV3AuthInitialDistDelay]] **TestingV3AuthInitialDistDelay** __N__ **minutes**|**hours**::
2910 Like V3AuthDistDelay, but for initial voting interval before
2911 the first consensus has been created. Changing this requires that
2912 **TestingTorNetwork** is set. (Default: 5 minutes)
2914 [[TestingV3AuthVotingStartOffset]] **TestingV3AuthVotingStartOffset** __N__ **seconds**|**minutes**|**hours**::
2915 Directory authorities offset voting start time by this much.
2916 Changing this requires that **TestingTorNetwork** is set. (Default: 0)
2918 [[TestingAuthDirTimeToLearnReachability]] **TestingAuthDirTimeToLearnReachability** __N__ **minutes**|**hours**::
2919 After starting as an authority, do not make claims about whether routers
2920 are Running until this much time has passed. Changing this requires
2921 that **TestingTorNetwork** is set. (Default: 30 minutes)
2923 [[TestingEstimatedDescriptorPropagationTime]] **TestingEstimatedDescriptorPropagationTime** __N__ **minutes**|**hours**::
2924 Clients try downloading server descriptors from directory caches after this
2925 time. Changing this requires that **TestingTorNetwork** is set. (Default:
2928 [[TestingMinFastFlagThreshold]] **TestingMinFastFlagThreshold** __N__ **bytes**|**KBytes**|**MBytes**|**GBytes**|**TBytes**|**KBits**|**MBits**|**GBits**|**TBits**::
2929 Minimum value for the Fast flag. Overrides the ordinary minimum taken
2930 from the consensus when TestingTorNetwork is set. (Default: 0.)
2932 [[TestingServerDownloadSchedule]] **TestingServerDownloadSchedule** __N__,__N__,__...__::
2933 Schedule for when servers should download things in general. Changing this
2934 requires that **TestingTorNetwork** is set. (Default: 0, 0, 0, 60, 60, 120,
2935 300, 900, 2147483647)
2937 [[TestingClientDownloadSchedule]] **TestingClientDownloadSchedule** __N__,__N__,__...__::
2938 Schedule for when clients should download things in general. Changing this
2939 requires that **TestingTorNetwork** is set. (Default: 0, 0, 60, 300, 600,
2942 [[TestingServerConsensusDownloadSchedule]] **TestingServerConsensusDownloadSchedule** __N__,__N__,__...__::
2943 Schedule for when servers should download consensuses. Changing this
2944 requires that **TestingTorNetwork** is set. (Default: 0, 0, 60, 300, 600,
2945 1800, 1800, 1800, 1800, 1800, 3600, 7200)
2947 [[TestingClientConsensusDownloadSchedule]] **TestingClientConsensusDownloadSchedule** __N__,__N__,__...__::
2948 Schedule for when clients should download consensuses. Changing this
2949 requires that **TestingTorNetwork** is set. (Default: 0, 0, 60, 300, 600,
2950 1800, 3600, 3600, 3600, 10800, 21600, 43200)
2952 [[TestingBridgeDownloadSchedule]] **TestingBridgeDownloadSchedule** __N__,__N__,__...__::
2953 Schedule for when clients should download each bridge descriptor when they
2954 know that one or more of their configured bridges are running. Changing
2955 this requires that **TestingTorNetwork** is set. (Default: 10800, 25200,
2956 54000, 111600, 262800)
2958 [[TestingBridgeBootstrapDownloadSchedule]] **TestingBridgeBootstrapDownloadSchedule** __N__,__N__,__...__::
2959 Schedule for when clients should download each bridge descriptor when they
2960 have just started, or when they can not contact any of their bridges.
2961 Changing this requires that **TestingTorNetwork** is set. (Default: 0, 30,
2962 90, 600, 3600, 10800, 25200, 54000, 111600, 262800)
2964 [[TestingClientMaxIntervalWithoutRequest]] **TestingClientMaxIntervalWithoutRequest** __N__ **seconds**|**minutes**::
2965 When directory clients have only a few descriptors to request, they batch
2966 them until they have more, or until this amount of time has passed.
2967 Changing this requires that **TestingTorNetwork** is set. (Default: 10
2970 [[TestingDirConnectionMaxStall]] **TestingDirConnectionMaxStall** __N__ **seconds**|**minutes**::
2971 Let a directory connection stall this long before expiring it.
2972 Changing this requires that **TestingTorNetwork** is set. (Default:
2975 [[TestingConsensusMaxDownloadTries]] **TestingConsensusMaxDownloadTries** __NUM__::
2976 Try this many times to download a consensus before giving up. Changing
2977 this requires that **TestingTorNetwork** is set. (Default: 8)
2979 [[TestingDescriptorMaxDownloadTries]] **TestingDescriptorMaxDownloadTries** __NUM__::
2980 Try this often to download a server descriptor before giving up.
2981 Changing this requires that **TestingTorNetwork** is set. (Default: 8)
2983 [[TestingMicrodescMaxDownloadTries]] **TestingMicrodescMaxDownloadTries** __NUM__::
2984 Try this often to download a microdesc descriptor before giving up.
2985 Changing this requires that **TestingTorNetwork** is set. (Default: 8)
2987 [[TestingCertMaxDownloadTries]] **TestingCertMaxDownloadTries** __NUM__::
2988 Try this often to download a v3 authority certificate before giving up.
2989 Changing this requires that **TestingTorNetwork** is set. (Default: 8)
2991 [[TestingDirAuthVoteExit]] **TestingDirAuthVoteExit** __node__,__node__,__...__::
2992 A list of identity fingerprints, country codes, and
2993 address patterns of nodes to vote Exit for regardless of their
2994 uptime, bandwidth, or exit policy. See the **ExcludeNodes**
2995 option for more information on how to specify nodes. +
2997 In order for this option to have any effect, **TestingTorNetwork**
2998 has to be set. See the **ExcludeNodes** option for more
2999 information on how to specify nodes.
3001 [[TestingDirAuthVoteExitIsStrict]] **TestingDirAuthVoteExitIsStrict** **0**|**1** ::
3002 If True (1), a node will never receive the Exit flag unless it is specified
3003 in the **TestingDirAuthVoteExit** list, regardless of its uptime, bandwidth,
3006 In order for this option to have any effect, **TestingTorNetwork**
3009 [[TestingDirAuthVoteGuard]] **TestingDirAuthVoteGuard** __node__,__node__,__...__::
3010 A list of identity fingerprints and country codes and
3011 address patterns of nodes to vote Guard for regardless of their
3012 uptime and bandwidth. See the **ExcludeNodes** option for more
3013 information on how to specify nodes. +
3015 In order for this option to have any effect, **TestingTorNetwork**
3018 [[TestingDirAuthVoteGuardIsStrict]] **TestingDirAuthVoteGuardIsStrict** **0**|**1** ::
3019 If True (1), a node will never receive the Guard flag unless it is specified
3020 in the **TestingDirAuthVoteGuard** list, regardless of its uptime and bandwidth. +
3022 In order for this option to have any effect, **TestingTorNetwork**
3025 [[TestingDirAuthVoteHSDir]] **TestingDirAuthVoteHSDir** __node__,__node__,__...__::
3026 A list of identity fingerprints and country codes and
3027 address patterns of nodes to vote HSDir for regardless of their
3028 uptime and DirPort. See the **ExcludeNodes** option for more
3029 information on how to specify nodes. +
3031 In order for this option to have any effect, **TestingTorNetwork**
3034 [[TestingDirAuthVoteHSDirIsStrict]] **TestingDirAuthVoteHSDirIsStrict** **0**|**1** ::
3035 If True (1), a node will never receive the HSDir flag unless it is specified
3036 in the **TestingDirAuthVoteHSDir** list, regardless of its uptime and DirPort. +
3038 In order for this option to have any effect, **TestingTorNetwork**
3041 [[TestingEnableConnBwEvent]] **TestingEnableConnBwEvent** **0**|**1**::
3042 If this option is set, then Tor controllers may register for CONN_BW
3043 events. Changing this requires that **TestingTorNetwork** is set.
3046 [[TestingEnableCellStatsEvent]] **TestingEnableCellStatsEvent** **0**|**1**::
3047 If this option is set, then Tor controllers may register for CELL_STATS
3048 events. Changing this requires that **TestingTorNetwork** is set.
3051 [[TestingEnableTbEmptyEvent]] **TestingEnableTbEmptyEvent** **0**|**1**::
3052 If this option is set, then Tor controllers may register for TB_EMPTY
3053 events. Changing this requires that **TestingTorNetwork** is set.
3056 [[TestingMinExitFlagThreshold]] **TestingMinExitFlagThreshold** __N__ **KBytes**|**MBytes**|**GBytes**|**TBytes**|**KBits**|**MBits**|**GBits**|**TBits**::
3057 Sets a lower-bound for assigning an exit flag when running as an
3058 authority on a testing network. Overrides the usual default lower bound
3059 of 4 KB. (Default: 0)
3061 [[TestingLinkCertLifetime]] **TestingLinkCertLifetime** __N__ **seconds**|**minutes**|**hours**|**days**|**weeks**|**months**::
3062 Overrides the default lifetime for the certificates used to authenticate
3063 our X509 link cert with our ed25519 signing key.
3066 [[TestingAuthKeyLifetime]] **TestingAuthKeyLifetime** __N__ **seconds**|**minutes**|**hours**|**days**|**weeks**|**months**::
3067 Overrides the default lifetime for a signing Ed25519 TLS Link authentication
3071 [[TestingLinkKeySlop]] **TestingLinkKeySlop** __N__ **seconds**|**minutes**|**hours** +
3073 [[TestingAuthKeySlop]] **TestingAuthKeySlop** __N__ **seconds**|**minutes**|**hours** +
3075 [[TestingSigningKeySlop]] **TestingSigningKeySlop** __N__ **seconds**|**minutes**|**hours**::
3076 How early before the official expiration of a an Ed25519 signing key do
3077 we replace it and issue a new key?
3078 (Default: 3 hours for link and auth; 1 day for signing.)
3080 NON-PERSISTENT OPTIONS
3081 ----------------------
3083 These options are not saved to the torrc file by the "SAVECONF" controller
3084 command. Other options of this type are documented in control-spec.txt,
3085 section 5.4. End-users should mostly ignore them.
3087 [[UnderscorePorts]] **\_\_ControlPort**, **\_\_DirPort**, **\_\_DNSPort**, **\_\_ExtORPort**, **\_\_NATDPort**, **\_\_ORPort**, **\_\_SocksPort**, **\_\_TransPort**::
3088 These underscore-prefixed options are variants of the regular Port
3089 options. They behave the same, except they are not saved to the
3090 torrc file by the controller's SAVECONF command.
3096 Tor catches the following signals:
3098 [[SIGTERM]] **SIGTERM**::
3099 Tor will catch this, clean up and sync to disk if necessary, and exit.
3101 [[SIGINT]] **SIGINT**::
3102 Tor clients behave as with SIGTERM; but Tor servers will do a controlled
3103 slow shutdown, closing listeners and waiting 30 seconds before exiting.
3104 (The delay can be configured with the ShutdownWaitLength config option.)
3106 [[SIGHUP]] **SIGHUP**::
3107 The signal instructs Tor to reload its configuration (including closing and
3108 reopening logs), and kill and restart its helper processes if applicable.
3110 [[SIGUSR1]] **SIGUSR1**::
3111 Log statistics about current connections, past connections, and throughput.
3113 [[SIGUSR2]] **SIGUSR2**::
3114 Switch all logs to loglevel debug. You can go back to the old loglevels by
3117 [[SIGCHLD]] **SIGCHLD**::
3118 Tor receives this signal when one of its helper processes has exited, so it
3121 [[SIGPIPE]] **SIGPIPE**::
3122 Tor catches this signal and ignores it.
3124 [[SIGXFSZ]] **SIGXFSZ**::
3125 If this signal exists on your platform, Tor catches and ignores it.
3130 **@CONFDIR@/torrc**::
3131 The configuration file, which contains "option value" pairs.
3134 Fallback location for torrc, if @CONFDIR@/torrc is not found.
3136 **@LOCALSTATEDIR@/lib/tor/**::
3137 The tor process stores keys and other data here.
3140 __CacheDirectory__**/cached-certs**::
3141 This file holds downloaded directory key certificates that are used to
3142 verify authenticity of documents generated by Tor directory authorities.
3144 __CacheDirectory__**/cached-consensus** and/or **cached-microdesc-consensus**::
3145 The most recent consensus network status document we've downloaded.
3147 __CacheDirectory__**/cached-descriptors** and **cached-descriptors.new**::
3148 These files hold downloaded router statuses. Some routers may appear more
3149 than once; if so, the most recently published descriptor is used. Lines
3150 beginning with @-signs are annotations that contain more information about
3151 a given router. The ".new" file is an append-only journal; when it gets
3152 too large, all entries are merged into a new cached-descriptors file.
3154 __CacheDirectory__**/cached-extrainfo** and **cached-extrainfo.new**::
3155 As "cached-descriptors", but holds optionally-downloaded "extra-info"
3156 documents. Relays use these documents to send inessential information
3157 about statistics, bandwidth history, and network health to the
3158 authorities. They aren't fetched by default; see the DownloadExtraInfo
3159 option for more info.
3161 __CacheDirectory__**/cached-microdescs** and **cached-microdescs.new**::
3162 These files hold downloaded microdescriptors. Lines beginning with
3163 @-signs are annotations that contain more information about a given
3164 router. The ".new" file is an append-only journal; when it gets too
3165 large, all entries are merged into a new cached-microdescs file.
3167 __CacheDirectory__**/cached-routers** and **cached-routers.new**::
3168 Obsolete versions of cached-descriptors and cached-descriptors.new. When
3169 Tor can't find the newer files, it looks here instead.
3171 __DataDirectory__**/state**::
3172 A set of persistent key-value mappings. These are documented in
3173 the file. These include:
3174 - The current entry guards and their status.
3175 - The current bandwidth accounting values.
3176 - When the file was last written
3177 - What version of Tor generated the state file
3178 - A short history of bandwidth usage, as produced in the server
3181 __DataDirectory__**/sr-state**::
3182 Authority only. State file used to record information about the current
3183 status of the shared-random-value voting state.
3185 __CacheDirectory__**/diff-cache**::
3186 Directory cache only. Holds older consensuses, and diffs from older
3187 consensuses to the most recent consensus of each type, compressed
3188 in various ways. Each file contains a set of key-value arguments
3189 decribing its contents, followed by a single NUL byte, followed by the
3192 __DataDirectory__**/bw_accounting**::
3193 Used to track bandwidth accounting values (when the current period starts
3194 and ends; how much has been read and written so far this period). This file
3195 is obsolete, and the data is now stored in the \'state' file instead.
3197 __DataDirectory__**/control_auth_cookie**::
3198 Used for cookie authentication with the controller. Location can be
3199 overridden by the CookieAuthFile config option. Regenerated on startup. See
3200 control-spec.txt in https://spec.torproject.org/[torspec] for details.
3201 Only used when cookie authentication is enabled.
3203 __DataDirectory__**/lock**::
3204 This file is used to prevent two Tor instances from using same data
3205 directory. If access to this file is locked, data directory is already
3208 __DataDirectory__**/key-pinning-journal**::
3209 Used by authorities. A line-based file that records mappings between
3210 RSA1024 identity keys and Ed25519 identity keys. Authorities enforce
3211 these mappings, so that once a relay has picked an Ed25519 key, stealing
3212 or factoring the RSA1024 key will no longer let an attacker impersonate
3215 __KeyDirectory__**/authority_identity_key**::
3216 A v3 directory authority's master identity key, used to authenticate its
3217 signing key. Tor doesn't use this while it's running. The tor-gencert
3218 program uses this. If you're running an authority, you should keep this
3219 key offline, and not actually put it here.
3221 __KeyDirectory__**/authority_certificate**::
3222 A v3 directory authority's certificate, which authenticates the authority's
3223 current vote- and consensus-signing key using its master identity key.
3224 Only directory authorities use this file.
3226 __KeyDirectory__**/authority_signing_key**::
3227 A v3 directory authority's signing key, used to sign votes and consensuses.
3228 Only directory authorities use this file. Corresponds to the
3229 **authority_certificate** cert.
3231 __KeyDirectory__**/legacy_certificate**::
3232 As authority_certificate: used only when V3AuthUseLegacyKey is set.
3233 See documentation for V3AuthUseLegacyKey.
3235 __KeyDirectory__**/legacy_signing_key**::
3236 As authority_signing_key: used only when V3AuthUseLegacyKey is set.
3237 See documentation for V3AuthUseLegacyKey.
3239 __KeyDirectory__**/secret_id_key**::
3240 A relay's RSA1024 permanent identity key, including private and public
3241 components. Used to sign router descriptors, and to sign other keys.
3243 __KeyDirectory__**/ed25519_master_id_public_key**::
3244 The public part of a relay's Ed25519 permanent identity key.
3246 __KeyDirectory__**/ed25519_master_id_secret_key**::
3247 The private part of a relay's Ed25519 permanent identity key. This key
3248 is used to sign the medium-term ed25519 signing key. This file can be
3249 kept offline, or kept encrypted. If so, Tor will not be able to generate
3250 new signing keys itself; you'll need to use tor --keygen yourself to do
3253 __KeyDirectory__**/ed25519_signing_secret_key**::
3254 The private and public components of a relay's medium-term Ed25519 signing
3255 key. This key is authenticated by the Ed25519 master key, in turn
3256 authenticates other keys (and router descriptors).
3258 __KeyDirectory__**/ed25519_signing_cert**::
3259 The certificate which authenticates "ed25519_signing_secret_key" as
3260 having been signed by the Ed25519 master key.
3262 __KeyDirectory__**/secret_onion_key** and **secret_onion_key.old**::
3263 A relay's RSA1024 short-term onion key. Used to decrypt old-style ("TAP")
3264 circuit extension requests. The ".old" file holds the previously
3265 generated key, which the relay uses to handle any requests that were
3266 made by clients that didn't have the new one.
3268 __KeyDirectory__**/secret_onion_key_ntor** and **secret_onion_key_ntor.old**::
3269 A relay's Curve25519 short-term onion key. Used to handle modern ("ntor")
3270 circuit extension requests. The ".old" file holds the previously
3271 generated key, which the relay uses to handle any requests that were
3272 made by clients that didn't have the new one.
3274 __DataDirectory__**/fingerprint**::
3275 Only used by servers. Holds the fingerprint of the server's identity key.
3277 __DataDirectory__**/hashed-fingerprint**::
3278 Only used by bridges. Holds the hashed fingerprint of the bridge's
3279 identity key. (That is, the hash of the hash of the identity key.)
3281 __DataDirectory__**/approved-routers**::
3282 Only used by authoritative directory servers. This file lists
3283 the status of routers by their identity fingerprint.
3284 Each line lists a status and a fingerprint separated by
3285 whitespace. See your **fingerprint** file in the __DataDirectory__ for an
3286 example line. If the status is **!reject** then descriptors from the
3287 given identity (fingerprint) are rejected by this server. If it is
3288 **!invalid** then descriptors are accepted but marked in the directory as
3289 not valid, that is, not recommended.
3291 __DataDirectory__**/v3-status-votes**::
3292 Only for v3 authoritative directory servers. This file contains
3293 status votes from all the authoritative directory servers.
3295 __CacheDirectory__**/unverified-consensus**::
3296 This file contains a network consensus document that has been downloaded,
3297 but which we didn't have the right certificates to check yet.
3299 __CacheDirectory__**/unverified-microdesc-consensus**::
3300 This file contains a microdescriptor-flavored network consensus document
3301 that has been downloaded, but which we didn't have the right certificates
3304 __DataDirectory__**/unparseable-desc**::
3305 Onion server descriptors that Tor was unable to parse are dumped to this
3306 file. Only used for debugging.
3308 __DataDirectory__**/router-stability**::
3309 Only used by authoritative directory servers. Tracks measurements for
3310 router mean-time-between-failures so that authorities have a good idea of
3311 how to set their Stable flags.
3313 __DataDirectory__**/stats/dirreq-stats**::
3314 Only used by directory caches and authorities. This file is used to
3315 collect directory request statistics.
3317 __DataDirectory__**/stats/entry-stats**::
3318 Only used by servers. This file is used to collect incoming connection
3319 statistics by Tor entry nodes.
3321 __DataDirectory__**/stats/bridge-stats**::
3322 Only used by servers. This file is used to collect incoming connection
3323 statistics by Tor bridges.
3325 __DataDirectory__**/stats/exit-stats**::
3326 Only used by servers. This file is used to collect outgoing connection
3327 statistics by Tor exit routers.
3329 __DataDirectory__**/stats/buffer-stats**::
3330 Only used by servers. This file is used to collect buffer usage
3333 __DataDirectory__**/stats/conn-stats**::
3334 Only used by servers. This file is used to collect approximate connection
3335 history (number of active connections over time).
3337 __DataDirectory__**/stats/hidserv-stats**::
3338 Only used by servers. This file is used to collect approximate counts
3339 of what fraction of the traffic is hidden service rendezvous traffic, and
3340 approximately how many hidden services the relay has seen.
3342 __DataDirectory__**/networkstatus-bridges**::
3343 Only used by authoritative bridge directories. Contains information
3344 about bridges that have self-reported themselves to the bridge
3347 __DataDirectory__**/approved-routers**::
3348 Authorities only. This file is used to configure which relays are
3349 known to be valid, invalid, and so forth.
3351 __HiddenServiceDirectory__**/hostname**::
3352 The <base32-encoded-fingerprint>.onion domain name for this hidden service.
3353 If the hidden service is restricted to authorized clients only, this file
3354 also contains authorization data for all clients.
3356 Note that clients will ignore any extra subdomains prepended to a hidden
3357 service hostname. So if you have "xyz.onion" as your hostname, you
3358 can tell clients to connect to "www.xyz.onion" or "irc.xyz.onion"
3359 for virtual-hosting purposes.
3361 __HiddenServiceDirectory__**/private_key**::
3362 The private key for this hidden service.
3364 __HiddenServiceDirectory__**/client_keys**::
3365 Authorization data for a hidden service that is only accessible by
3368 __HiddenServiceDirectory__**/onion_service_non_anonymous**::
3369 This file is present if a hidden service key was created in
3370 **HiddenServiceNonAnonymousMode**.
3374 **torsocks**(1), **torify**(1) +
3376 **https://www.torproject.org/**
3378 **torspec: https://spec.torproject.org **
3383 Plenty, probably. Tor is still in development. Please report them at https://trac.torproject.org/.
3387 Roger Dingledine [arma at mit.edu], Nick Mathewson [nickm at alum.mit.edu].