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 this option is set manually, or via the "perconnbwrate" consensus
246 field, Tor will use it for separate rate limiting for each connection
247 from a non-relay. (Default: 0)
249 [[PerConnBWBurst]] **PerConnBWBurst** __N__ **bytes**|**KBytes**|**MBytes**|**GBytes**|**TBytes**|**KBits**|**MBits**|**GBits**|**TBits**::
250 If this option is set manually, or via the "perconnbwburst" consensus
251 field, Tor will use it for separate rate limiting for each connection
252 from a non-relay. (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. Tor will make still certain
315 network-related calls (like DNS lookups) as a part of its configuration
316 process, even if DisableNetwork is set. (Default: 0)
318 [[ConstrainedSockets]] **ConstrainedSockets** **0**|**1**::
319 If set, Tor will tell the kernel to attempt to shrink the buffers for all
320 sockets to the size specified in **ConstrainedSockSize**. This is useful for
321 virtual servers and other environments where system level TCP buffers may
322 be limited. If you're on a virtual server, and you encounter the "Error
323 creating network socket: No buffer space available" message, you are
324 likely experiencing this problem. +
326 The preferred solution is to have the admin increase the buffer pool for
327 the host itself via /proc/sys/net/ipv4/tcp_mem or equivalent facility;
328 this configuration option is a second-resort. +
330 The DirPort option should also not be used if TCP buffers are scarce. The
331 cached directory requests consume additional sockets which exacerbates
334 You should **not** enable this feature unless you encounter the "no buffer
335 space available" issue. Reducing the TCP buffers affects window size for
336 the TCP stream and will reduce throughput in proportion to round trip
337 time on long paths. (Default: 0)
339 [[ConstrainedSockSize]] **ConstrainedSockSize** __N__ **bytes**|**KBytes**::
340 When **ConstrainedSockets** is enabled the receive and transmit buffers for
341 all sockets will be set to this limit. Must be a value between 2048 and
342 262144, in 1024 byte increments. Default of 8192 is recommended.
344 [[ControlPort]] **ControlPort** __PORT__|**unix:**__path__|**auto** [__flags__]::
345 If set, Tor will accept connections on this port and allow those
346 connections to control the Tor process using the Tor Control Protocol
347 (described in control-spec.txt in
348 https://spec.torproject.org[torspec]). Note: unless you also
349 specify one or more of **HashedControlPassword** or
350 **CookieAuthentication**, setting this option will cause Tor to allow
351 any process on the local host to control it. (Setting both authentication
352 methods means either method is sufficient to authenticate to Tor.) This
353 option is required for many Tor controllers; most use the value of 9051.
354 If a unix domain socket is used, you may quote the path using standard
356 Set it to "auto" to have Tor pick a port for you. (Default: 0) +
358 Recognized flags are...
360 Unix domain sockets only: makes the socket get created as
363 Unix domain sockets only: makes the socket get created as
365 **RelaxDirModeCheck**;;
366 Unix domain sockets only: Do not insist that the directory
367 that holds the socket be read-restricted.
369 [[ControlSocket]] **ControlSocket** __Path__::
370 Like ControlPort, but listens on a Unix domain socket, rather than a TCP
371 socket. '0' disables ControlSocket. (Unix and Unix-like systems only.)
374 [[ControlSocketsGroupWritable]] **ControlSocketsGroupWritable** **0**|**1**::
375 If this option is set to 0, don't allow the filesystem group to read and
376 write unix sockets (e.g. ControlSocket). If the option is set to 1, make
377 the control socket readable and writable by the default GID. (Default: 0)
379 [[HashedControlPassword]] **HashedControlPassword** __hashed_password__::
380 Allow connections on the control port if they present
381 the password whose one-way hash is __hashed_password__. You
382 can compute the hash of a password by running "tor --hash-password
383 __password__". You can provide several acceptable passwords by using more
384 than one HashedControlPassword line.
386 [[CookieAuthentication]] **CookieAuthentication** **0**|**1**::
387 If this option is set to 1, allow connections on the control port
388 when the connecting process knows the contents of a file named
389 "control_auth_cookie", which Tor will create in its data directory. This
390 authentication method should only be used on systems with good filesystem
391 security. (Default: 0)
393 [[CookieAuthFile]] **CookieAuthFile** __Path__::
394 If set, this option overrides the default location and file name
395 for Tor's cookie file. (See CookieAuthentication above.)
397 [[CookieAuthFileGroupReadable]] **CookieAuthFileGroupReadable** **0**|**1**::
398 If this option is set to 0, don't allow the filesystem group to read the
399 cookie file. If the option is set to 1, make the cookie file readable by
400 the default GID. [Making the file readable by other groups is not yet
401 implemented; let us know if you need this for some reason.] (Default: 0)
403 [[ControlPortWriteToFile]] **ControlPortWriteToFile** __Path__::
404 If set, Tor writes the address and port of any control port it opens to
405 this address. Usable by controllers to learn the actual control port
406 when ControlPort is set to "auto".
408 [[ControlPortFileGroupReadable]] **ControlPortFileGroupReadable** **0**|**1**::
409 If this option is set to 0, don't allow the filesystem group to read the
410 control port file. If the option is set to 1, make the control port
411 file readable by the default GID. (Default: 0)
413 [[DataDirectory]] **DataDirectory** __DIR__::
414 Store working data in DIR. Can not be changed while tor is running.
415 (Default: ~/.tor if your home directory is not /; otherwise,
416 @LOCALSTATEDIR@/lib/tor. On Windows, the default is
417 your ApplicationData folder.)
419 [[DataDirectoryGroupReadable]] **DataDirectoryGroupReadable** **0**|**1**::
420 If this option is set to 0, don't allow the filesystem group to read the
421 DataDirectory. If the option is set to 1, make the DataDirectory readable
422 by the default GID. (Default: 0)
424 [[CacheDirectory]] **CacheDirectory** __DIR__::
425 Store cached directory data in DIR. Can not be changed while tor is
427 (Default: uses the value of DataDirectory.)
429 [[CacheDirectoryGroupReadable]] **CacheDirectoryGroupReadable** **0**|**1**::
430 If this option is set to 0, don't allow the filesystem group to read the
431 CacheDirectory. If the option is set to 1, make the CacheDirectory readable
432 by the default GID. (Default: 0)
434 [[FallbackDir]] **FallbackDir** __ipv4address__:__port__ orport=__port__ id=__fingerprint__ [weight=__num__] [ipv6=**[**__ipv6address__**]**:__orport__]::
435 When we're unable to connect to any directory cache for directory info
436 (usually because we don't know about any yet) we try a directory authority.
437 Clients also simultaneously try a FallbackDir, to avoid hangs on client
438 startup if a directory authority is down. Clients retry FallbackDirs more
439 often than directory authorities, to reduce the load on the directory
441 By default, the directory authorities are also FallbackDirs. Specifying a
442 FallbackDir replaces Tor's default hard-coded FallbackDirs (if any).
443 (See the **DirAuthority** entry for an explanation of each flag.)
445 [[UseDefaultFallbackDirs]] **UseDefaultFallbackDirs** **0**|**1**::
446 Use Tor's default hard-coded FallbackDirs (if any). (When a
447 FallbackDir line is present, it replaces the hard-coded FallbackDirs,
448 regardless of the value of UseDefaultFallbackDirs.) (Default: 1)
450 [[DirAuthority]] **DirAuthority** [__nickname__] [**flags**] __ipv4address__:__port__ __fingerprint__::
451 Use a nonstandard authoritative directory server at the provided address
452 and port, with the specified key fingerprint. This option can be repeated
453 many times, for multiple authoritative directory servers. Flags are
454 separated by spaces, and determine what kind of an authority this directory
455 is. By default, an authority is not authoritative for any directory style
456 or version unless an appropriate flag is given.
457 Tor will use this authority as a bridge authoritative directory if the
458 "bridge" flag is set. If a flag "orport=**port**" is given, Tor will use the
459 given port when opening encrypted tunnels to the dirserver. If a flag
460 "weight=**num**" is given, then the directory server is chosen randomly
461 with probability proportional to that weight (default 1.0). If a
462 flag "v3ident=**fp**" is given, the dirserver is a v3 directory authority
463 whose v3 long-term signing key has the fingerprint **fp**. Lastly,
464 if an "ipv6=**[**__ipv6address__**]**:__orport__" flag is present, then
466 authority is listening for IPv6 connections on the indicated IPv6 address
469 Tor will contact the authority at __ipv4address__ to
470 download directory documents. The provided __port__ value is a dirport;
471 clients ignore this in favor of the specified "orport=" value. If an
472 IPv6 ORPort is supplied, Tor will
473 also download directory documents at the IPv6 ORPort. +
475 If no **DirAuthority** line is given, Tor will use the default directory
476 authorities. NOTE: this option is intended for setting up a private Tor
477 network with its own directory authorities. If you use it, you will be
478 distinguishable from other users, because you won't believe the same
481 [[DirAuthorityFallbackRate]] **DirAuthorityFallbackRate** __NUM__::
482 When configured to use both directory authorities and fallback
483 directories, the directory authorities also work as fallbacks. They are
484 chosen with their regular weights, multiplied by this number, which
485 should be 1.0 or less. The default is less than 1, to reduce load on
486 authorities. (Default: 0.1)
488 [[AlternateDirAuthority]] **AlternateDirAuthority** [__nickname__] [**flags**] __ipv4address__:__port__ __fingerprint__ +
490 [[AlternateBridgeAuthority]] **AlternateBridgeAuthority** [__nickname__] [**flags**] __ipv4address__:__port__ __ fingerprint__::
491 These options behave as DirAuthority, but they replace fewer of the
492 default directory authorities. Using
493 AlternateDirAuthority replaces the default Tor directory authorities, but
494 leaves the default bridge authorities in
496 AlternateBridgeAuthority replaces the default bridge authority,
497 but leaves the directory authorities alone.
499 [[DisableAllSwap]] **DisableAllSwap** **0**|**1**::
500 If set to 1, Tor will attempt to lock all current and future memory pages,
501 so that memory cannot be paged out. Windows, OS X and Solaris are currently
502 not supported. We believe that this feature works on modern Gnu/Linux
503 distributions, and that it should work on *BSD systems (untested). This
504 option requires that you start your Tor as root, and you should use the
505 **User** option to properly reduce Tor's privileges.
506 Can not be changed while tor is running. (Default: 0)
508 [[DisableDebuggerAttachment]] **DisableDebuggerAttachment** **0**|**1**::
509 If set to 1, Tor will attempt to prevent basic debugging attachment attempts
510 by other processes. This may also keep Tor from generating core files if
511 it crashes. It has no impact for users who wish to attach if they
512 have CAP_SYS_PTRACE or if they are root. We believe that this feature
513 works on modern Gnu/Linux distributions, and that it may also work on *BSD
514 systems (untested). Some modern Gnu/Linux systems such as Ubuntu have the
515 kernel.yama.ptrace_scope sysctl and by default enable it as an attempt to
516 limit the PTRACE scope for all user processes by default. This feature will
517 attempt to limit the PTRACE scope for Tor specifically - it will not attempt
518 to alter the system wide ptrace scope as it may not even exist. If you wish
519 to attach to Tor with a debugger such as gdb or strace you will want to set
520 this to 0 for the duration of your debugging. Normal users should leave it
521 on. Disabling this option while Tor is running is prohibited. (Default: 1)
523 [[FetchDirInfoEarly]] **FetchDirInfoEarly** **0**|**1**::
524 If set to 1, Tor will always fetch directory information like other
525 directory caches, even if you don't meet the normal criteria for fetching
526 early. Normal users should leave it off. (Default: 0)
528 [[FetchDirInfoExtraEarly]] **FetchDirInfoExtraEarly** **0**|**1**::
529 If set to 1, Tor will fetch directory information before other directory
530 caches. It will attempt to download directory information closer to the
531 start of the consensus period. Normal users should leave it off.
534 [[FetchHidServDescriptors]] **FetchHidServDescriptors** **0**|**1**::
535 If set to 0, Tor will never fetch any hidden service descriptors from the
536 rendezvous directories. This option is only useful if you're using a Tor
537 controller that handles hidden service fetches for you. (Default: 1)
539 [[FetchServerDescriptors]] **FetchServerDescriptors** **0**|**1**::
540 If set to 0, Tor will never fetch any network status summaries or server
541 descriptors from the directory servers. This option is only useful if
542 you're using a Tor controller that handles directory fetches for you.
545 [[FetchUselessDescriptors]] **FetchUselessDescriptors** **0**|**1**::
546 If set to 1, Tor will fetch every consensus flavor, and all server
547 descriptors and authority certificates referenced by those consensuses,
548 except for extra info descriptors. When this option is 1, Tor will also
549 keep fetching descriptors, even when idle.
550 If set to 0, Tor will avoid fetching useless descriptors: flavors that it
551 is not using to build circuits, and authority certificates it does not
552 trust. When Tor hasn't built any application circuits, it will go idle,
553 and stop fetching descriptors. This option is useful if you're using a
554 tor client with an external parser that uses a full consensus.
555 This option fetches all documents except extrainfo descriptors,
556 **DirCache** fetches and serves all documents except extrainfo
557 descriptors, **DownloadExtraInfo*** fetches extrainfo documents, and serves
558 them if **DirCache** is on, and **UseMicrodescriptors** changes the
559 flavour of consensues and descriptors that is fetched and used for
560 building circuits. (Default: 0)
562 [[HTTPProxy]] **HTTPProxy** __host__[:__port__]::
563 Tor will make all its directory requests through this host:port (or host:80
564 if port is not specified), rather than connecting directly to any directory
565 servers. (DEPRECATED: As of 0.3.1.0-alpha you should use HTTPSProxy.)
567 [[HTTPProxyAuthenticator]] **HTTPProxyAuthenticator** __username:password__::
568 If defined, Tor will use this username:password for Basic HTTP proxy
569 authentication, as in RFC 2617. This is currently the only form of HTTP
570 proxy authentication that Tor supports; feel free to submit a patch if you
571 want it to support others. (DEPRECATED: As of 0.3.1.0-alpha you should use
572 HTTPSProxyAuthenticator.)
574 [[HTTPSProxy]] **HTTPSProxy** __host__[:__port__]::
575 Tor will make all its OR (SSL) connections through this host:port (or
576 host:443 if port is not specified), via HTTP CONNECT rather than connecting
577 directly to servers. You may want to set **FascistFirewall** to restrict
578 the set of ports you might try to connect to, if your HTTPS proxy only
579 allows connecting to certain ports.
581 [[HTTPSProxyAuthenticator]] **HTTPSProxyAuthenticator** __username:password__::
582 If defined, Tor will use this username:password for Basic HTTPS proxy
583 authentication, as in RFC 2617. This is currently the only form of HTTPS
584 proxy authentication that Tor supports; feel free to submit a patch if you
585 want it to support others.
587 [[Sandbox]] **Sandbox** **0**|**1**::
588 If set to 1, Tor will run securely through the use of a syscall sandbox.
589 Otherwise the sandbox will be disabled. The option is currently an
590 experimental feature. It only works on Linux-based operating systems,
591 and only when Tor has been built with the libseccomp library. This option
592 can not be changed while tor is running.
594 When the Sandbox is 1, the following options can not be changed when tor
600 ExtORPortCookieAuthFile
602 ServerDNSResolvConfFile
603 Tor must remain in client or server mode (some changes to ClientOnly and
604 ORPort are not allowed).
607 [[Socks4Proxy]] **Socks4Proxy** __host__[:__port__]::
608 Tor will make all OR connections through the SOCKS 4 proxy at host:port
609 (or host:1080 if port is not specified).
611 [[Socks5Proxy]] **Socks5Proxy** __host__[:__port__]::
612 Tor will make all OR connections through the SOCKS 5 proxy at host:port
613 (or host:1080 if port is not specified).
615 [[Socks5ProxyUsername]] **Socks5ProxyUsername** __username__ +
617 [[Socks5ProxyPassword]] **Socks5ProxyPassword** __password__::
618 If defined, authenticate to the SOCKS 5 server using username and password
619 in accordance to RFC 1929. Both username and password must be between 1 and
622 [[UnixSocksGroupWritable]] **UnixSocksGroupWritable** **0**|**1**::
623 If this option is set to 0, don't allow the filesystem group to read and
624 write unix sockets (e.g. SocksPort unix:). If the option is set to 1, make
625 the Unix socket readable and writable by the default GID. (Default: 0)
627 [[KeepalivePeriod]] **KeepalivePeriod** __NUM__::
628 To keep firewalls from expiring connections, send a padding keepalive cell
629 every NUM seconds on open connections that are in use. If the connection
630 has no open circuits, it will instead be closed after NUM seconds of
631 idleness. (Default: 5 minutes)
633 [[Log]] **Log** __minSeverity__[-__maxSeverity__] **stderr**|**stdout**|**syslog**::
634 Send all messages between __minSeverity__ and __maxSeverity__ to the standard
635 output stream, the standard error stream, or to the system log. (The
636 "syslog" value is only supported on Unix.) Recognized severity levels are
637 debug, info, notice, warn, and err. We advise using "notice" in most cases,
638 since anything more verbose may provide sensitive information to an
639 attacker who obtains the logs. If only one severity level is given, all
640 messages of that level or higher will be sent to the listed destination.
642 [[Log2]] **Log** __minSeverity__[-__maxSeverity__] **file** __FILENAME__::
643 As above, but send log messages to the listed filename. The
644 "Log" option may appear more than once in a configuration file.
645 Messages are sent to all the logs that match their severity
648 [[Log3]] **Log** **[**__domain__,...**]**__minSeverity__[-__maxSeverity__] ... **file** __FILENAME__ +
650 [[Log4]] **Log** **[**__domain__,...**]**__minSeverity__[-__maxSeverity__] ... **stderr**|**stdout**|**syslog**::
651 As above, but select messages by range of log severity __and__ by a
652 set of "logging domains". Each logging domain corresponds to an area of
653 functionality inside Tor. You can specify any number of severity ranges
654 for a single log statement, each of them prefixed by a comma-separated
655 list of logging domains. You can prefix a domain with $$~$$ to indicate
656 negation, and use * to indicate "all domains". If you specify a severity
657 range without a list of domains, it matches all domains. +
659 This is an advanced feature which is most useful for debugging one or two
660 of Tor's subsystems at a time. +
662 The currently recognized domains are: general, crypto, net, config, fs,
663 protocol, mm, http, app, control, circ, rend, bug, dir, dirserv, or, edge,
664 acct, hist, handshake, heartbeat, channel, sched, guard, consdiff, and dos.
665 Domain names are case-insensitive. +
667 For example, "`Log [handshake]debug [~net,~mm]info notice stdout`" sends
668 to stdout: all handshake messages of any severity, all info-and-higher
669 messages from domains other than networking and memory management, and all
670 messages of severity notice or higher.
672 [[LogMessageDomains]] **LogMessageDomains** **0**|**1**::
673 If 1, Tor includes message domains with each log message. Every log
674 message currently has at least one domain; most currently have exactly
675 one. This doesn't affect controller log messages. (Default: 0)
677 [[MaxUnparseableDescSizeToLog]] **MaxUnparseableDescSizeToLog** __N__ **bytes**|**KBytes**|**MBytes**|**GBytes**|**TBytes**::
678 Unparseable descriptors (e.g. for votes, consensuses, routers) are logged
679 in separate files by hash, up to the specified size in total. Note that
680 only files logged during the lifetime of this Tor process count toward the
681 total; this is intended to be used to debug problems without opening live
682 servers to resource exhaustion attacks. (Default: 10 MB)
684 [[OutboundBindAddress]] **OutboundBindAddress** __IP__::
685 Make all outbound connections originate from the IP address specified. This
686 is only useful when you have multiple network interfaces, and you want all
687 of Tor's outgoing connections to use a single one. This option may
688 be used twice, once with an IPv4 address and once with an IPv6 address.
689 IPv6 addresses should be wrapped in square brackets.
690 This setting will be ignored for connections to the loopback addresses
691 (127.0.0.0/8 and ::1), and is not used for DNS requests as well.
693 [[OutboundBindAddressOR]] **OutboundBindAddressOR** __IP__::
694 Make all outbound non-exit (relay and other) connections
695 originate from the IP address specified. This option overrides
696 **OutboundBindAddress** for the same IP version. This option may
697 be used twice, once with an IPv4 address and once with an IPv6
698 address. IPv6 addresses should be wrapped in square brackets.
699 This setting will be ignored for connections to the loopback
700 addresses (127.0.0.0/8 and ::1).
702 [[OutboundBindAddressExit]] **OutboundBindAddressExit** __IP__::
703 Make all outbound exit connections originate from the IP address
704 specified. This option overrides **OutboundBindAddress** for the
705 same IP version. This option may be used twice, once with an IPv4
706 address and once with an IPv6 address.
707 IPv6 addresses should be wrapped in square brackets.
708 This setting will be ignored
709 for connections to the loopback addresses (127.0.0.0/8 and ::1).
711 [[PidFile]] **PidFile** __FILE__::
712 On startup, write our PID to FILE. On clean shutdown, remove
713 FILE. Can not be changed while tor is running.
715 [[ProtocolWarnings]] **ProtocolWarnings** **0**|**1**::
716 If 1, Tor will log with severity \'warn' various cases of other parties not
717 following the Tor specification. Otherwise, they are logged with severity
718 \'info'. (Default: 0)
720 [[RunAsDaemon]] **RunAsDaemon** **0**|**1**::
721 If 1, Tor forks and daemonizes to the background. This option has no effect
722 on Windows; instead you should use the --service command-line option.
723 Can not be changed while tor is running.
726 [[LogTimeGranularity]] **LogTimeGranularity** __NUM__::
727 Set the resolution of timestamps in Tor's logs to NUM milliseconds.
728 NUM must be positive and either a divisor or a multiple of 1 second.
729 Note that this option only controls the granularity written by Tor to
730 a file or console log. Tor does not (for example) "batch up" log
731 messages to affect times logged by a controller, times attached to
732 syslog messages, or the mtime fields on log files. (Default: 1 second)
734 [[TruncateLogFile]] **TruncateLogFile** **0**|**1**::
735 If 1, Tor will overwrite logs at startup and in response to a HUP signal,
736 instead of appending to them. (Default: 0)
738 [[SyslogIdentityTag]] **SyslogIdentityTag** __tag__::
739 When logging to syslog, adds a tag to the syslog identity such that
740 log entries are marked with "Tor-__tag__". Can not be changed while tor is
741 running. (Default: none)
743 [[AndroidIdentityTag]] **AndroidIdentityTag** __tag__::
744 When logging to Android's logging subsystem, adds a tag to the log identity
745 such that log entries are marked with "Tor-__tag__". Can not be changed while
746 tor is running. (Default: none)
748 [[SafeLogging]] **SafeLogging** **0**|**1**|**relay**::
749 Tor can scrub potentially sensitive strings from log messages (e.g.
750 addresses) by replacing them with the string [scrubbed]. This way logs can
751 still be useful, but they don't leave behind personally identifying
752 information about what sites a user might have visited. +
754 If this option is set to 0, Tor will not perform any scrubbing, if it is
755 set to 1, all potentially sensitive strings are replaced. If it is set to
756 relay, all log messages generated when acting as a relay are sanitized, but
757 all messages generated when acting as a client are not. (Default: 1)
759 [[User]] **User** __Username__::
760 On startup, setuid to this user and setgid to their primary group.
761 Can not be changed while tor is running.
763 [[KeepBindCapabilities]] **KeepBindCapabilities** **0**|**1**|**auto**::
764 On Linux, when we are started as root and we switch our identity using
765 the **User** option, the **KeepBindCapabilities** option tells us whether to
766 try to retain our ability to bind to low ports. If this value is 1, we
767 try to keep the capability; if it is 0 we do not; and if it is **auto**,
768 we keep the capability only if we are configured to listen on a low port.
769 Can not be changed while tor is running.
772 [[HardwareAccel]] **HardwareAccel** **0**|**1**::
773 If non-zero, try to use built-in (static) crypto hardware acceleration when
774 available. Can not be changed while tor is running. (Default: 0)
776 [[AccelName]] **AccelName** __NAME__::
777 When using OpenSSL hardware crypto acceleration attempt to load the dynamic
778 engine of this name. This must be used for any dynamic hardware engine.
779 Names can be verified with the openssl engine command. Can not be changed
780 while tor is running.
782 [[AccelDir]] **AccelDir** __DIR__::
783 Specify this option if using dynamic hardware acceleration and the engine
784 implementation library resides somewhere other than the OpenSSL default.
785 Can not be changed while tor is running.
787 [[AvoidDiskWrites]] **AvoidDiskWrites** **0**|**1**::
788 If non-zero, try to write to disk less frequently than we would otherwise.
789 This is useful when running on flash memory or other media that support
790 only a limited number of writes. (Default: 0)
792 [[CircuitPriorityHalflife]] **CircuitPriorityHalflife** __NUM__::
793 If this value is set, we override the default algorithm for choosing which
794 circuit's cell to deliver or relay next. It is delivered first to the
795 circuit that has the lowest weighted cell count, where cells are weighted
796 exponentially according to this value (in seconds). If the value is -1, it
797 is taken from the consensus if possible else it will fallback to the
798 default value of 30. Minimum: 1, Maximum: 2147483647. This can be defined
799 as a float value. This is an advanced option; you generally shouldn't have
800 to mess with it. (Default: -1)
802 [[CountPrivateBandwidth]] **CountPrivateBandwidth** **0**|**1**::
803 If this option is set, then Tor's rate-limiting applies not only to
804 remote connections, but also to connections to private addresses like
805 127.0.0.1 or 10.0.0.1. This is mostly useful for debugging
806 rate-limiting. (Default: 0)
808 [[ExtendByEd25519ID]] **ExtendByEd25519ID** **0**|**1**|**auto**::
809 If this option is set to 1, we always try to include a relay's Ed25519 ID
810 when telling the proceeding relay in a circuit to extend to it.
811 If this option is set to 0, we never include Ed25519 IDs when extending
812 circuits. If the option is set to "default", we obey a
813 parameter in the consensus document. (Default: auto)
815 [[NoExec]] **NoExec** **0**|**1**::
816 If this option is set to 1, then Tor will never launch another
817 executable, regardless of the settings of ClientTransportPlugin
818 or ServerTransportPlugin. Once this option has been set to 1,
819 it cannot be set back to 0 without restarting Tor. (Default: 0)
821 [[Schedulers]] **Schedulers** **KIST**|**KISTLite**|**Vanilla**::
822 Specify the scheduler type that tor should use. The scheduler is
823 responsible for moving data around within a Tor process. This is an ordered
824 list by priority which means that the first value will be tried first and if
825 unavailable, the second one is tried and so on. It is possible to change
826 these values at runtime. This option mostly effects relays, and most
827 operators should leave it set to its default value.
828 (Default: KIST,KISTLite,Vanilla)
830 The possible scheduler types are:
832 **KIST**: Kernel-Informed Socket Transport. Tor will use TCP information
833 from the kernel to make informed decisions regarding how much data to send
834 and when to send it. KIST also handles traffic in batches (see
835 KISTSchedRunInterval) in order to improve traffic prioritization decisions.
836 As implemented, KIST will only work on Linux kernel version 2.6.39 or
839 **KISTLite**: Same as KIST but without kernel support. Tor will use all
840 the same mechanics as with KIST, including the batching, but its decisions
841 regarding how much data to send will not be as good. KISTLite will work on
842 all kernels and operating systems, and the majority of the benefits of KIST
843 are still realized with KISTLite.
845 **Vanilla**: The scheduler that Tor used before KIST was implemented. It
846 sends as much data as possible, as soon as possible. Vanilla will work on
847 all kernels and operating systems.
849 [[KISTSchedRunInterval]] **KISTSchedRunInterval** __NUM__ **msec**::
850 If KIST or KISTLite is used in the Schedulers option, this controls at which
851 interval the scheduler tick is. If the value is 0 msec, the value is taken
852 from the consensus if possible else it will fallback to the default 10
853 msec. Maximum possible value is 100 msec. (Default: 0 msec)
855 [[KISTSockBufSizeFactor]] **KISTSockBufSizeFactor** __NUM__::
856 If KIST is used in Schedulers, this is a multiplier of the per-socket
857 limit calculation of the KIST algorithm. (Default: 1.0)
862 The following options are useful only for clients (that is, if
863 **SocksPort**, **HTTPTunnelPort**, **TransPort**, **DNSPort**, or
864 **NATDPort** is non-zero):
866 [[Bridge]] **Bridge** [__transport__] __IP__:__ORPort__ [__fingerprint__]::
867 When set along with UseBridges, instructs Tor to use the relay at
868 "IP:ORPort" as a "bridge" relaying into the Tor network. If "fingerprint"
869 is provided (using the same format as for DirAuthority), we will verify that
870 the relay running at that location has the right fingerprint. We also use
871 fingerprint to look up the bridge descriptor at the bridge authority, if
872 it's provided and if UpdateBridgesFromAuthority is set too. +
874 If "transport" is provided, it must match a ClientTransportPlugin line. We
875 then use that pluggable transport's proxy to transfer data to the bridge,
876 rather than connecting to the bridge directly. Some transports use a
877 transport-specific method to work out the remote address to connect to.
878 These transports typically ignore the "IP:ORPort" specified in the bridge
881 Tor passes any "key=val" settings to the pluggable transport proxy as
882 per-connection arguments when connecting to the bridge. Consult
883 the documentation of the pluggable transport for details of what
884 arguments it supports.
886 [[LearnCircuitBuildTimeout]] **LearnCircuitBuildTimeout** **0**|**1**::
887 If 0, CircuitBuildTimeout adaptive learning is disabled. (Default: 1)
889 [[CircuitBuildTimeout]] **CircuitBuildTimeout** __NUM__::
891 Try for at most NUM seconds when building circuits. If the circuit isn't
892 open in that time, give up on it. If LearnCircuitBuildTimeout is 1, this
893 value serves as the initial value to use before a timeout is learned. If
894 LearnCircuitBuildTimeout is 0, this value is the only value used.
895 (Default: 60 seconds)
897 [[CircuitsAvailableTimeout]] **CircuitsAvailableTimeout** __NUM__::
898 Tor will attempt to keep at least one open, unused circuit available for
899 this amount of time. This option governs how long idle circuits are kept
900 open, as well as the amount of time Tor will keep a circuit open to each
901 of the recently used ports. This way when the Tor client is entirely
902 idle, it can expire all of its circuits, and then expire its TLS
903 connections. Note that the actual timeout value is uniformly randomized
904 from the specified value to twice that amount. (Default: 30 minutes;
907 [[CircuitStreamTimeout]] **CircuitStreamTimeout** __NUM__::
908 If non-zero, this option overrides our internal timeout schedule for how
909 many seconds until we detach a stream from a circuit and try a new circuit.
910 If your network is particularly slow, you might want to set this to a
911 number like 60. (Default: 0)
913 [[ClientOnly]] **ClientOnly** **0**|**1**::
914 If set to 1, Tor will not run as a relay or serve
915 directory requests, even if the ORPort, ExtORPort, or DirPort options are
916 set. (This config option is
917 mostly unnecessary: we added it back when we were considering having
918 Tor clients auto-promote themselves to being relays if they were stable
919 and fast enough. The current behavior is simply that Tor is a client
920 unless ORPort, ExtORPort, or DirPort are configured.) (Default: 0)
922 [[ConnectionPadding]] **ConnectionPadding** **0**|**1**|**auto**::
923 This option governs Tor's use of padding to defend against some forms of
924 traffic analysis. If it is set to 'auto', Tor will send padding only
925 if both the client and the relay support it. If it is set to 0, Tor will
926 not send any padding cells. If it is set to 1, Tor will still send padding
927 for client connections regardless of relay support. Only clients may set
928 this option. This option should be offered via the UI to mobile users
929 for use where bandwidth may be expensive.
932 [[ReducedConnectionPadding]] **ReducedConnectionPadding** **0**|**1**::
933 If set to 1, Tor will not not hold OR connections open for very long,
934 and will send less padding on these connections. Only clients may set
935 this option. This option should be offered via the UI to mobile users
936 for use where bandwidth may be expensive. (Default: 0)
938 [[ExcludeNodes]] **ExcludeNodes** __node__,__node__,__...__::
939 A list of identity fingerprints, country codes, and address
940 patterns of nodes to avoid when building a circuit. Country codes are
941 2-letter ISO3166 codes, and must
942 be wrapped in braces; fingerprints may be preceded by a dollar sign.
944 ExcludeNodes ABCD1234CDEF5678ABCD1234CDEF5678ABCD1234, \{cc}, 255.254.0.0/8) +
946 By default, this option is treated as a preference that Tor is allowed
947 to override in order to keep working.
948 For example, if you try to connect to a hidden service,
949 but you have excluded all of the hidden service's introduction points,
950 Tor will connect to one of them anyway. If you do not want this
951 behavior, set the StrictNodes option (documented below). +
953 Note also that if you are a relay, this (and the other node selection
954 options below) only affects your own circuits that Tor builds for you.
955 Clients can still build circuits through you to any node. Controllers
956 can tell Tor to build circuits through any node. +
958 Country codes are case-insensitive. The code "\{??}" refers to nodes whose
959 country can't be identified. No country code, including \{??}, works if
960 no GeoIPFile can be loaded. See also the GeoIPExcludeUnknown option below.
963 [[ExcludeExitNodes]] **ExcludeExitNodes** __node__,__node__,__...__::
964 A list of identity fingerprints, country codes, and address
965 patterns of nodes to never use when picking an exit node---that is, a
966 node that delivers traffic for you *outside* the Tor network. Note that any
967 node listed in ExcludeNodes is automatically considered to be part of this
969 the **ExcludeNodes** option for more information on how to specify
970 nodes. See also the caveats on the "ExitNodes" option below.
972 [[GeoIPExcludeUnknown]] **GeoIPExcludeUnknown** **0**|**1**|**auto**::
973 If this option is set to 'auto', then whenever any country code is set in
974 ExcludeNodes or ExcludeExitNodes, all nodes with unknown country (\{??} and
975 possibly \{A1}) are treated as excluded as well. If this option is set to
976 '1', then all unknown countries are treated as excluded in ExcludeNodes
977 and ExcludeExitNodes. This option has no effect when a GeoIP file isn't
978 configured or can't be found. (Default: auto)
980 [[ExitNodes]] **ExitNodes** __node__,__node__,__...__::
981 A list of identity fingerprints, country codes, and address
982 patterns of nodes to use as exit node---that is, a
983 node that delivers traffic for you *outside* the Tor network. See
984 the **ExcludeNodes** option for more information on how to specify nodes. +
986 Note that if you list too few nodes here, or if you exclude too many exit
987 nodes with ExcludeExitNodes, you can degrade functionality. For example,
988 if none of the exits you list allows traffic on port 80 or 443, you won't
989 be able to browse the web. +
991 Note also that not every circuit is used to deliver traffic *outside* of
992 the Tor network. It is normal to see non-exit circuits (such as those
993 used to connect to hidden services, those that do directory fetches,
994 those used for relay reachability self-tests, and so on) that end
995 at a non-exit node. To
996 keep a node from being used entirely, see ExcludeNodes and StrictNodes. +
998 The ExcludeNodes option overrides this option: any node listed in both
999 ExitNodes and ExcludeNodes is treated as excluded. +
1001 The .exit address notation, if enabled via MapAddress, overrides
1004 [[EntryNodes]] **EntryNodes** __node__,__node__,__...__::
1005 A list of identity fingerprints and country codes of nodes
1006 to use for the first hop in your normal circuits.
1007 Normal circuits include all
1008 circuits except for direct connections to directory servers. The Bridge
1009 option overrides this option; if you have configured bridges and
1010 UseBridges is 1, the Bridges are used as your entry nodes. +
1012 The ExcludeNodes option overrides this option: any node listed in both
1013 EntryNodes and ExcludeNodes is treated as excluded. See
1014 the **ExcludeNodes** option for more information on how to specify nodes.
1016 [[StrictNodes]] **StrictNodes** **0**|**1**::
1017 If StrictNodes is set to 1, Tor will treat solely the ExcludeNodes option
1018 as a requirement to follow for all the circuits you generate, even if
1019 doing so will break functionality for you (StrictNodes applies to neither
1020 ExcludeExitNodes nor to ExitNodes). If StrictNodes is set to 0, Tor will
1021 still try to avoid nodes in the ExcludeNodes list, but it will err on the
1022 side of avoiding unexpected errors. Specifically, StrictNodes 0 tells Tor
1023 that it is okay to use an excluded node when it is *necessary* to perform
1024 relay reachability self-tests, connect to a hidden service, provide a
1025 hidden service to a client, fulfill a .exit request, upload directory
1026 information, or download directory information. (Default: 0)
1028 [[FascistFirewall]] **FascistFirewall** **0**|**1**::
1029 If 1, Tor will only create outgoing connections to ORs running on ports
1030 that your firewall allows (defaults to 80 and 443; see **FirewallPorts**).
1031 This will allow you to run Tor as a client behind a firewall with
1032 restrictive policies, but will not allow you to run as a server behind such
1033 a firewall. If you prefer more fine-grained control, use
1034 ReachableAddresses instead.
1036 [[FirewallPorts]] **FirewallPorts** __PORTS__::
1037 A list of ports that your firewall allows you to connect to. Only used when
1038 **FascistFirewall** is set. This option is deprecated; use ReachableAddresses
1039 instead. (Default: 80, 443)
1041 [[ReachableAddresses]] **ReachableAddresses** __IP__[/__MASK__][:__PORT__]...::
1042 A comma-separated list of IP addresses and ports that your firewall allows
1043 you to connect to. The format is as for the addresses in ExitPolicy, except
1044 that "accept" is understood unless "reject" is explicitly provided. For
1045 example, \'ReachableAddresses 99.0.0.0/8, reject 18.0.0.0/8:80, accept
1046 \*:80' means that your firewall allows connections to everything inside net
1047 99, rejects port 80 connections to net 18, and accepts connections to port
1048 80 otherwise. (Default: \'accept \*:*'.)
1050 [[ReachableDirAddresses]] **ReachableDirAddresses** __IP__[/__MASK__][:__PORT__]...::
1051 Like **ReachableAddresses**, a list of addresses and ports. Tor will obey
1052 these restrictions when fetching directory information, using standard HTTP
1053 GET requests. If not set explicitly then the value of
1054 **ReachableAddresses** is used. If **HTTPProxy** is set then these
1055 connections will go through that proxy. (DEPRECATED: This option has
1056 had no effect for some time.)
1058 [[ReachableORAddresses]] **ReachableORAddresses** __IP__[/__MASK__][:__PORT__]...::
1059 Like **ReachableAddresses**, a list of addresses and ports. Tor will obey
1060 these restrictions when connecting to Onion Routers, using TLS/SSL. If not
1061 set explicitly then the value of **ReachableAddresses** is used. If
1062 **HTTPSProxy** is set then these connections will go through that proxy. +
1064 The separation between **ReachableORAddresses** and
1065 **ReachableDirAddresses** is only interesting when you are connecting
1066 through proxies (see **HTTPProxy** and **HTTPSProxy**). Most proxies limit
1067 TLS connections (which Tor uses to connect to Onion Routers) to port 443,
1068 and some limit HTTP GET requests (which Tor uses for fetching directory
1069 information) to port 80.
1071 [[HidServAuth]] **HidServAuth** __onion-address__ __auth-cookie__ [__service-name__]::
1072 Client authorization for a hidden service. Valid onion addresses contain 16
1073 characters in a-z2-7 plus ".onion", and valid auth cookies contain 22
1074 characters in A-Za-z0-9+/. The service name is only used for internal
1075 purposes, e.g., for Tor controllers. This option may be used multiple times
1076 for different hidden services. If a hidden service uses authorization and
1077 this option is not set, the hidden service is not accessible. Hidden
1078 services can be configured to require authorization using the
1079 **HiddenServiceAuthorizeClient** option.
1081 [[LongLivedPorts]] **LongLivedPorts** __PORTS__::
1082 A list of ports for services that tend to have long-running connections
1083 (e.g. chat and interactive shells). Circuits for streams that use these
1084 ports will contain only high-uptime nodes, to reduce the chance that a node
1085 will go down before the stream is finished. Note that the list is also
1086 honored for circuits (both client and service side) involving hidden
1087 services whose virtual port is in this list. (Default: 21, 22, 706,
1088 1863, 5050, 5190, 5222, 5223, 6523, 6667, 6697, 8300)
1090 [[MapAddress]] **MapAddress** __address__ __newaddress__::
1091 When a request for address arrives to Tor, it will transform to newaddress
1092 before processing it. For example, if you always want connections to
1093 www.example.com to exit via __torserver__ (where __torserver__ is the
1094 fingerprint of the server), use "MapAddress www.example.com
1095 www.example.com.torserver.exit". If the value is prefixed with a
1096 "\*.", matches an entire domain. For example, if you
1097 always want connections to example.com and any if its subdomains
1099 __torserver__ (where __torserver__ is the fingerprint of the server), use
1100 "MapAddress \*.example.com \*.example.com.torserver.exit". (Note the
1101 leading "*." in each part of the directive.) You can also redirect all
1102 subdomains of a domain to a single address. For example, "MapAddress
1103 *.example.com www.example.com". +
1107 1. When evaluating MapAddress expressions Tor stops when it hits the most
1108 recently added expression that matches the requested address. So if you
1109 have the following in your torrc, www.torproject.org will map to 1.1.1.1:
1111 MapAddress www.torproject.org 2.2.2.2
1112 MapAddress www.torproject.org 1.1.1.1
1114 2. Tor evaluates the MapAddress configuration until it finds no matches. So
1115 if you have the following in your torrc, www.torproject.org will map to
1118 MapAddress 1.1.1.1 2.2.2.2
1119 MapAddress www.torproject.org 1.1.1.1
1121 3. The following MapAddress expression is invalid (and will be
1122 ignored) because you cannot map from a specific address to a wildcard
1125 MapAddress www.torproject.org *.torproject.org.torserver.exit
1127 4. Using a wildcard to match only part of a string (as in *ample.com) is
1130 [[NewCircuitPeriod]] **NewCircuitPeriod** __NUM__::
1131 Every NUM seconds consider whether to build a new circuit. (Default: 30
1134 [[MaxCircuitDirtiness]] **MaxCircuitDirtiness** __NUM__::
1135 Feel free to reuse a circuit that was first used at most NUM seconds ago,
1136 but never attach a new stream to a circuit that is too old. For hidden
1137 services, this applies to the __last__ time a circuit was used, not the
1138 first. Circuits with streams constructed with SOCKS authentication via
1139 SocksPorts that have **KeepAliveIsolateSOCKSAuth** also remain alive
1140 for MaxCircuitDirtiness seconds after carrying the last such stream.
1141 (Default: 10 minutes)
1143 [[MaxClientCircuitsPending]] **MaxClientCircuitsPending** __NUM__::
1144 Do not allow more than NUM circuits to be pending at a time for handling
1145 client streams. A circuit is pending if we have begun constructing it,
1146 but it has not yet been completely constructed. (Default: 32)
1148 [[NodeFamily]] **NodeFamily** __node__,__node__,__...__::
1149 The Tor servers, defined by their identity fingerprints,
1150 constitute a "family" of similar or co-administered servers, so never use
1151 any two of them in the same circuit. Defining a NodeFamily is only needed
1152 when a server doesn't list the family itself (with MyFamily). This option
1153 can be used multiple times; each instance defines a separate family. In
1154 addition to nodes, you can also list IP address and ranges and country
1155 codes in {curly braces}. See the **ExcludeNodes** option for more
1156 information on how to specify nodes.
1158 [[EnforceDistinctSubnets]] **EnforceDistinctSubnets** **0**|**1**::
1159 If 1, Tor will not put two servers whose IP addresses are "too close" on
1160 the same circuit. Currently, two addresses are "too close" if they lie in
1161 the same /16 range. (Default: 1)
1163 [[SocksPort]] **SocksPort** \['address':]__port__|**unix:**__path__|**auto** [_flags_] [_isolation flags_]::
1164 Open this port to listen for connections from SOCKS-speaking
1165 applications. Set this to 0 if you don't want to allow application
1166 connections via SOCKS. Set it to "auto" to have Tor pick a port for
1167 you. This directive can be specified multiple times to bind
1168 to multiple addresses/ports. If a unix domain socket is used, you may
1169 quote the path using standard C escape sequences.
1172 NOTE: Although this option allows you to specify an IP address
1173 other than localhost, you should do so only with extreme caution.
1174 The SOCKS protocol is unencrypted and (as we use it)
1175 unauthenticated, so exposing it in this way could leak your
1176 information to anybody watching your network, and allow anybody
1177 to use your computer as an open proxy. +
1179 The _isolation flags_ arguments give Tor rules for which streams
1180 received on this SocksPort are allowed to share circuits with one
1181 another. Recognized isolation flags are:
1182 **IsolateClientAddr**;;
1183 Don't share circuits with streams from a different
1184 client address. (On by default and strongly recommended when
1185 supported; you can disable it with **NoIsolateClientAddr**.
1186 Unsupported and force-disabled when using Unix domain sockets.)
1187 **IsolateSOCKSAuth**;;
1188 Don't share circuits with streams for which different
1189 SOCKS authentication was provided. (For HTTPTunnelPort
1190 connections, this option looks at the Proxy-Authorization and
1191 X-Tor-Stream-Isolation headers. On by default;
1192 you can disable it with **NoIsolateSOCKSAuth**.)
1193 **IsolateClientProtocol**;;
1194 Don't share circuits with streams using a different protocol.
1195 (SOCKS 4, SOCKS 5, TransPort connections, NATDPort connections,
1196 and DNSPort requests are all considered to be different protocols.)
1197 **IsolateDestPort**;;
1198 Don't share circuits with streams targeting a different
1200 **IsolateDestAddr**;;
1201 Don't share circuits with streams targeting a different
1202 destination address.
1203 **KeepAliveIsolateSOCKSAuth**;;
1204 If **IsolateSOCKSAuth** is enabled, keep alive circuits while they have
1205 at least one stream with SOCKS authentication active. After such a circuit
1206 is idle for more than MaxCircuitDirtiness seconds, it can be closed.
1207 **SessionGroup=**__INT__;;
1208 If no other isolation rules would prevent it, allow streams
1209 on this port to share circuits with streams from every other
1210 port with the same session group. (By default, streams received
1211 on different SocksPorts, TransPorts, etc are always isolated from one
1212 another. This option overrides that behavior.)
1214 // Anchor only for formatting, not visible in the man page.
1215 [[OtherSocksPortFlags]]::
1216 Other recognized __flags__ for a SocksPort are:
1218 Tell exits to not connect to IPv4 addresses in response to SOCKS
1219 requests on this connection.
1221 Tell exits to allow IPv6 addresses in response to SOCKS requests on
1222 this connection, so long as SOCKS5 is in use. (SOCKS4 can't handle
1225 Tells exits that, if a host has both an IPv4 and an IPv6 address,
1226 we would prefer to connect to it via IPv6. (IPv4 is the default.)
1228 Do not ask exits to resolve DNS addresses in SOCKS5 requests. Tor will
1229 connect to IPv4 addresses, IPv6 addresses (if IPv6Traffic is set) and
1231 **NoOnionTraffic**;;
1232 Do not connect to .onion addresses in SOCKS5 requests.
1233 **OnionTrafficOnly**;;
1234 Tell the tor client to only connect to .onion addresses in response to
1235 SOCKS5 requests on this connection. This is equivalent to NoDNSRequest,
1236 NoIPv4Traffic, NoIPv6Traffic. The corresponding NoOnionTrafficOnly
1237 flag is not supported.
1239 Tells the client to remember IPv4 DNS answers we receive from exit
1240 nodes via this connection.
1242 Tells the client to remember IPv6 DNS answers we receive from exit
1243 nodes via this connection.
1245 Unix domain sockets only: makes the socket get created as
1248 Unix domain sockets only: makes the socket get created as
1251 Tells the client to remember all DNS answers we receive from exit
1252 nodes via this connection.
1254 Tells the client to use any cached IPv4 DNS answers we have when making
1255 requests via this connection. (NOTE: This option, or UseIPv6Cache
1256 or UseDNSCache, can harm your anonymity, and probably
1257 won't help performance as much as you might expect. Use with care!)
1259 Tells the client to use any cached IPv6 DNS answers we have when making
1260 requests via this connection.
1262 Tells the client to use any cached DNS answers we have when making
1263 requests via this connection.
1264 **PreferIPv6Automap**;;
1265 When serving a hostname lookup request on this port that
1266 should get automapped (according to AutomapHostsOnResolve),
1267 if we could return either an IPv4 or an IPv6 answer, prefer
1268 an IPv6 answer. (On by default.)
1269 **PreferSOCKSNoAuth**;;
1270 Ordinarily, when an application offers both "username/password
1271 authentication" and "no authentication" to Tor via SOCKS5, Tor
1272 selects username/password authentication so that IsolateSOCKSAuth can
1273 work. This can confuse some applications, if they offer a
1274 username/password combination then get confused when asked for
1275 one. You can disable this behavior, so that Tor will select "No
1276 authentication" when IsolateSOCKSAuth is disabled, or when this
1279 // Anchor only for formatting, not visible in the man page.
1280 [[SocksPortFlagsMisc]]::
1281 Flags are processed left to right. If flags conflict, the last flag on the
1282 line is used, and all earlier flags are ignored. No error is issued for
1285 [[SocksPolicy]] **SocksPolicy** __policy__,__policy__,__...__::
1286 Set an entrance policy for this server, to limit who can connect to the
1287 SocksPort and DNSPort ports. The policies have the same form as exit
1288 policies below, except that port specifiers are ignored. Any address
1289 not matched by some entry in the policy is accepted.
1291 [[SocksTimeout]] **SocksTimeout** __NUM__::
1292 Let a socks connection wait NUM seconds handshaking, and NUM seconds
1293 unattached waiting for an appropriate circuit, before we fail it. (Default:
1296 [[TokenBucketRefillInterval]] **TokenBucketRefillInterval** __NUM__ [**msec**|**second**]::
1297 Set the refill delay interval of Tor's token bucket to NUM milliseconds.
1298 NUM must be between 1 and 1000, inclusive. When Tor is out of bandwidth,
1299 on a connection or globally, it will wait up to this long before it tries
1300 to use that connection again.
1301 Note that bandwidth limits are still expressed in bytes per second: this
1302 option only affects the frequency with which Tor checks to see whether
1303 previously exhausted connections may read again.
1304 Can not be changed while tor is running. (Default: 100 msec)
1306 [[TrackHostExits]] **TrackHostExits** __host__,__.domain__,__...__::
1307 For each value in the comma separated list, Tor will track recent
1308 connections to hosts that match this value and attempt to reuse the same
1309 exit node for each. If the value is prepended with a \'.\', it is treated as
1310 matching an entire domain. If one of the values is just a \'.', it means
1311 match everything. This option is useful if you frequently connect to sites
1312 that will expire all your authentication cookies (i.e. log you out) if
1313 your IP address changes. Note that this option does have the disadvantage
1314 of making it more clear that a given history is associated with a single
1315 user. However, most people who would wish to observe this will observe it
1316 through cookies or other protocol-specific means anyhow.
1318 [[TrackHostExitsExpire]] **TrackHostExitsExpire** __NUM__::
1319 Since exit servers go up and down, it is desirable to expire the
1320 association between host and exit server after NUM seconds. The default is
1321 1800 seconds (30 minutes).
1323 [[UpdateBridgesFromAuthority]] **UpdateBridgesFromAuthority** **0**|**1**::
1324 When set (along with UseBridges), Tor will try to fetch bridge descriptors
1325 from the configured bridge authorities when feasible. It will fall back to
1326 a direct request if the authority responds with a 404. (Default: 0)
1328 [[UseBridges]] **UseBridges** **0**|**1**::
1329 When set, Tor will fetch descriptors for each bridge listed in the "Bridge"
1330 config lines, and use these relays as both entry guards and directory
1331 guards. (Default: 0)
1333 [[UseEntryGuards]] **UseEntryGuards** **0**|**1**::
1334 If this option is set to 1, we pick a few long-term entry servers, and try
1335 to stick with them. This is desirable because constantly changing servers
1336 increases the odds that an adversary who owns some servers will observe a
1337 fraction of your paths. Entry Guards can not be used by Directory
1338 Authorities, Single Onion Services, and Tor2web clients. In these cases,
1339 the this option is ignored. (Default: 1)
1341 [[GuardfractionFile]] **GuardfractionFile** __FILENAME__::
1342 V3 authoritative directories only. Configures the location of the
1343 guardfraction file which contains information about how long relays
1344 have been guards. (Default: unset)
1346 [[UseGuardFraction]] **UseGuardFraction** **0**|**1**|**auto**::
1347 This torrc option specifies whether clients should use the
1348 guardfraction information found in the consensus during path
1349 selection. If it's set to 'auto', clients will do what the
1350 UseGuardFraction consensus parameter tells them to do. (Default: auto)
1352 [[NumEntryGuards]] **NumEntryGuards** __NUM__::
1353 If UseEntryGuards is set to 1, we will try to pick a total of NUM routers
1354 as long-term entries for our circuits. If NUM is 0, we try to learn the
1355 number from the guard-n-primary-guards-to-use consensus parameter, and
1356 default to 1 if the consensus parameter isn't set. (Default: 0)
1358 [[NumPrimaryGuards]] **NumPrimaryGuards** __NUM__::
1359 If UseEntryGuards is set to 1, we will try to pick NUM routers for our
1360 primary guard list, which is the set of routers we strongly prefer when
1361 connecting to the Tor network. If NUM is 0, we try to learn the number from
1362 the guard-n-primary-guards consensus parameter, and default to 3 if the
1363 consensus parameter isn't set. (Default: 0)
1365 [[NumDirectoryGuards]] **NumDirectoryGuards** __NUM__::
1366 If UseEntryGuards is set to 1, we try to make sure we have at least NUM
1367 routers to use as directory guards. If this option is set to 0, use the
1368 value from the guard-n-primary-dir-guards-to-use consensus parameter, and
1369 default to 3 if the consensus parameter isn't set. (Default: 0)
1371 [[GuardLifetime]] **GuardLifetime** __N__ **days**|**weeks**|**months**::
1372 If nonzero, and UseEntryGuards is set, minimum time to keep a guard before
1373 picking a new one. If zero, we use the GuardLifetime parameter from the
1374 consensus directory. No value here may be less than 1 month or greater
1375 than 5 years; out-of-range values are clamped. (Default: 0)
1377 [[SafeSocks]] **SafeSocks** **0**|**1**::
1378 When this option is enabled, Tor will reject application connections that
1379 use unsafe variants of the socks protocol -- ones that only provide an IP
1380 address, meaning the application is doing a DNS resolve first.
1381 Specifically, these are socks4 and socks5 when not doing remote DNS.
1384 [[TestSocks]] **TestSocks** **0**|**1**::
1385 When this option is enabled, Tor will make a notice-level log entry for
1386 each connection to the Socks port indicating whether the request used a
1387 safe socks protocol or an unsafe one (see above entry on SafeSocks). This
1388 helps to determine whether an application using Tor is possibly leaking
1389 DNS requests. (Default: 0)
1391 [[VirtualAddrNetworkIPv4]] **VirtualAddrNetworkIPv4** __IPv4Address__/__bits__ +
1393 [[VirtualAddrNetworkIPv6]] **VirtualAddrNetworkIPv6** [__IPv6Address__]/__bits__::
1394 When Tor needs to assign a virtual (unused) address because of a MAPADDRESS
1395 command from the controller or the AutomapHostsOnResolve feature, Tor
1396 picks an unassigned address from this range. (Defaults:
1397 127.192.0.0/10 and [FE80::]/10 respectively.) +
1399 When providing proxy server service to a network of computers using a tool
1400 like dns-proxy-tor, change the IPv4 network to "10.192.0.0/10" or
1401 "172.16.0.0/12" and change the IPv6 network to "[FC00::]/7".
1402 The default **VirtualAddrNetwork** address ranges on a
1403 properly configured machine will route to the loopback or link-local
1404 interface. The maximum number of bits for the network prefix is set to 104
1405 for IPv6 and 16 for IPv4. However, a wider network - smaller prefix length
1406 - is preferable since it reduces the chances for an attacker to guess the
1407 used IP. For local use, no change to the default VirtualAddrNetwork setting
1410 [[AllowNonRFC953Hostnames]] **AllowNonRFC953Hostnames** **0**|**1**::
1411 When this option is disabled, Tor blocks hostnames containing illegal
1412 characters (like @ and :) rather than sending them to an exit node to be
1413 resolved. This helps trap accidental attempts to resolve URLs and so on.
1416 [[HTTPTunnelPort]] **HTTPTunnelPort** \['address':]__port__|**auto** [_isolation flags_]::
1417 Open this port to listen for proxy connections using the "HTTP CONNECT"
1418 protocol instead of SOCKS. Set this to
1419 0 if you don't want to allow "HTTP CONNECT" connections. Set the port
1420 to "auto" to have Tor pick a port for you. This directive can be
1421 specified multiple times to bind to multiple addresses/ports. See
1422 SOCKSPort for an explanation of isolation flags. (Default: 0)
1424 [[TransPort]] **TransPort** \['address':]__port__|**auto** [_isolation flags_]::
1425 Open this port to listen for transparent proxy connections. Set this to
1426 0 if you don't want to allow transparent proxy connections. Set the port
1427 to "auto" to have Tor pick a port for you. This directive can be
1428 specified multiple times to bind to multiple addresses/ports. See
1429 SOCKSPort for an explanation of isolation flags. +
1431 TransPort requires OS support for transparent proxies, such as BSDs' pf or
1432 Linux's IPTables. If you're planning to use Tor as a transparent proxy for
1433 a network, you'll want to examine and change VirtualAddrNetwork from the
1434 default setting. (Default: 0)
1436 [[TransProxyType]] **TransProxyType** **default**|**TPROXY**|**ipfw**|**pf-divert**::
1437 TransProxyType may only be enabled when there is transparent proxy listener
1440 Set this to "TPROXY" if you wish to be able to use the TPROXY Linux module
1441 to transparently proxy connections that are configured using the TransPort
1442 option. Detailed information on how to configure the TPROXY
1443 feature can be found in the Linux kernel source tree in the file
1444 Documentation/networking/tproxy.txt. +
1446 Set this option to "ipfw" to use the FreeBSD ipfw interface. +
1448 On *BSD operating systems when using pf, set this to "pf-divert" to take
1449 advantage of +divert-to+ rules, which do not modify the packets like
1450 +rdr-to+ rules do. Detailed information on how to configure pf to use
1451 +divert-to+ rules can be found in the pf.conf(5) manual page. On OpenBSD,
1452 +divert-to+ is available to use on versions greater than or equal to
1455 Set this to "default", or leave it unconfigured, to use regular IPTables
1456 on Linux, or to use pf +rdr-to+ rules on *BSD systems. +
1458 (Default: "default")
1460 [[NATDPort]] **NATDPort** \['address':]__port__|**auto** [_isolation flags_]::
1461 Open this port to listen for connections from old versions of ipfw (as
1462 included in old versions of FreeBSD, etc) using the NATD protocol.
1463 Use 0 if you don't want to allow NATD connections. Set the port
1464 to "auto" to have Tor pick a port for you. This directive can be
1465 specified multiple times to bind to multiple addresses/ports. See
1466 SocksPort for an explanation of isolation flags. +
1468 This option is only for people who cannot use TransPort. (Default: 0)
1470 [[AutomapHostsOnResolve]] **AutomapHostsOnResolve** **0**|**1**::
1471 When this option is enabled, and we get a request to resolve an address
1472 that ends with one of the suffixes in **AutomapHostsSuffixes**, we map an
1473 unused virtual address to that address, and return the new virtual address.
1474 This is handy for making ".onion" addresses work with applications that
1475 resolve an address and then connect to it. (Default: 0)
1477 [[AutomapHostsSuffixes]] **AutomapHostsSuffixes** __SUFFIX__,__SUFFIX__,__...__::
1478 A comma-separated list of suffixes to use with **AutomapHostsOnResolve**.
1479 The "." suffix is equivalent to "all addresses." (Default: .exit,.onion).
1481 [[DNSPort]] **DNSPort** \['address':]__port__|**auto** [_isolation flags_]::
1482 If non-zero, open this port to listen for UDP DNS requests, and resolve
1483 them anonymously. This port only handles A, AAAA, and PTR requests---it
1484 doesn't handle arbitrary DNS request types. Set the port to "auto" to
1485 have Tor pick a port for
1486 you. This directive can be specified multiple times to bind to multiple
1487 addresses/ports. See SocksPort for an explanation of isolation
1490 [[ClientDNSRejectInternalAddresses]] **ClientDNSRejectInternalAddresses** **0**|**1**::
1491 If true, Tor does not believe any anonymously retrieved DNS answer that
1492 tells it that an address resolves to an internal address (like 127.0.0.1 or
1493 192.168.0.1). This option prevents certain browser-based attacks; it
1494 is not allowed to be set on the default network. (Default: 1)
1496 [[ClientRejectInternalAddresses]] **ClientRejectInternalAddresses** **0**|**1**::
1497 If true, Tor does not try to fulfill requests to connect to an internal
1498 address (like 127.0.0.1 or 192.168.0.1) __unless an exit node is
1499 specifically requested__ (for example, via a .exit hostname, or a
1500 controller request). If true, multicast DNS hostnames for machines on the
1501 local network (of the form *.local) are also rejected. (Default: 1)
1503 [[DownloadExtraInfo]] **DownloadExtraInfo** **0**|**1**::
1504 If true, Tor downloads and caches "extra-info" documents. These documents
1505 contain information about servers other than the information in their
1506 regular server descriptors. Tor does not use this information for anything
1507 itself; to save bandwidth, leave this option turned off. (Default: 0)
1509 [[WarnPlaintextPorts]] **WarnPlaintextPorts** __port__,__port__,__...__::
1510 Tells Tor to issue a warnings whenever the user tries to make an anonymous
1511 connection to one of these ports. This option is designed to alert users
1512 to services that risk sending passwords in the clear. (Default:
1515 [[RejectPlaintextPorts]] **RejectPlaintextPorts** __port__,__port__,__...__::
1516 Like WarnPlaintextPorts, but instead of warning about risky port uses, Tor
1517 will instead refuse to make the connection. (Default: None)
1519 [[OptimisticData]] **OptimisticData** **0**|**1**|**auto**::
1520 When this option is set, and Tor is using an exit node that supports
1521 the feature, it will try optimistically to send data to the exit node
1522 without waiting for the exit node to report whether the connection
1523 succeeded. This can save a round-trip time for protocols like HTTP
1524 where the client talks first. If OptimisticData is set to **auto**,
1525 Tor will look at the UseOptimisticData parameter in the networkstatus.
1528 [[Tor2webMode]] **Tor2webMode** **0**|**1**::
1529 When this option is set, Tor connects to hidden services
1530 **non-anonymously**. This option also disables client connections to
1531 non-hidden-service hostnames through Tor. It **must only** be used when
1532 running a tor2web Hidden Service web proxy.
1533 To enable this option the compile time flag --enable-tor2web-mode must be
1534 specified. Since Tor2webMode is non-anonymous, you can not run an
1535 anonymous Hidden Service on a tor version compiled with Tor2webMode.
1538 [[Tor2webRendezvousPoints]] **Tor2webRendezvousPoints** __node__,__node__,__...__::
1539 A list of identity fingerprints, nicknames, country codes and
1540 address patterns of nodes that are allowed to be used as RPs
1541 in HS circuits; any other nodes will not be used as RPs.
1543 Tor2webRendezvousPoints Fastyfasty, ABCD1234CDEF5678ABCD1234CDEF5678ABCD1234, \{cc}, 255.254.0.0/8) +
1545 This feature can only be used if Tor2webMode is also enabled. +
1547 ExcludeNodes have higher priority than Tor2webRendezvousPoints,
1548 which means that nodes specified in ExcludeNodes will not be
1551 If no nodes in Tor2webRendezvousPoints are currently available for
1552 use, Tor will choose a random node when building HS circuits.
1554 [[HSLayer2Nodes]] **HSLayer2Nodes** __node__,__node__,__...__::
1555 A list of identity fingerprints, nicknames, country codes, and
1556 address patterns of nodes that are allowed to be used as the
1557 second hop in all client or service-side Onion Service circuits.
1558 This option mitigates attacks where the adversary runs middle nodes
1559 and induces your client or service to create many circuits, in order
1560 to discover your primary guard node.
1561 (Default: Any node in the network may be used in the second hop.)
1564 HSLayer2Nodes ABCD1234CDEF5678ABCD1234CDEF5678ABCD1234, \{cc}, 255.254.0.0/8) +
1566 When this is set, the resulting hidden service paths will
1569 C - G - L2 - M - Rend +
1570 C - G - L2 - M - HSDir +
1571 C - G - L2 - M - Intro +
1572 S - G - L2 - M - Rend +
1573 S - G - L2 - M - HSDir +
1574 S - G - L2 - M - Intro +
1576 where C is this client, S is the service, G is the Guard node,
1577 L2 is a node from this option, and M is a random middle node.
1578 Rend, HSDir, and Intro point selection is not affected by this
1581 This option may be combined with HSLayer3Nodes to create
1584 C - G - L2 - L3 - Rend +
1585 C - G - L2 - L3 - M - HSDir +
1586 C - G - L2 - L3 - M - Intro +
1587 S - G - L2 - L3 - M - Rend +
1588 S - G - L2 - L3 - HSDir +
1589 S - G - L2 - L3 - Intro +
1591 ExcludeNodes have higher priority than HSLayer2Nodes,
1592 which means that nodes specified in ExcludeNodes will not be
1595 When either this option or HSLayer3Nodes are set, the /16 subnet
1596 and node family restrictions are removed for hidden service
1597 circuits. Additionally, we allow the guard node to be present
1598 as the Rend, HSDir, and IP node, and as the hop before it. This
1599 is done to prevent the adversary from inferring information
1600 about our guard, layer2, and layer3 node choices at later points
1603 This option is meant to be managed by a Tor controller such as
1604 https://github.com/mikeperry-tor/vanguards that selects and
1605 updates this set of nodes for you. Hence it does not do load
1606 balancing if fewer than 20 nodes are selected, and if no nodes in
1607 HSLayer2Nodes are currently available for use, Tor will not work.
1608 Please use extreme care if you are setting this option manually.
1610 [[HSLayer3Nodes]] **HSLayer3Nodes** __node__,__node__,__...__::
1611 A list of identity fingerprints, nicknames, country codes, and
1612 address patterns of nodes that are allowed to be used as the
1613 third hop in all client and service-side Onion Service circuits.
1614 This option mitigates attacks where the adversary runs middle nodes
1615 and induces your client or service to create many circuits, in order
1616 to discover your primary or Layer2 guard nodes.
1617 (Default: Any node in the network may be used in the third hop.)
1620 HSLayer3Nodes ABCD1234CDEF5678ABCD1234CDEF5678ABCD1234, \{cc}, 255.254.0.0/8) +
1622 When this is set by itself, the resulting hidden service paths
1624 C - G - M - L3 - Rend +
1625 C - G - M - L3 - M - HSDir +
1626 C - G - M - L3 - M - Intro +
1627 S - G - M - L3 - M - Rend +
1628 S - G - M - L3 - HSDir +
1629 S - G - M - L3 - Intro +
1630 where C is this client, S is the service, G is the Guard node,
1631 L2 is a node from this option, and M is a random middle node.
1632 Rend, HSDir, and Intro point selection is not affected by this
1635 While it is possible to use this option by itself, it should be
1636 combined with HSLayer2Nodes to create paths of the form:
1638 C - G - L2 - L3 - Rend +
1639 C - G - L2 - L3 - M - HSDir +
1640 C - G - L2 - L3 - M - Intro +
1641 S - G - L2 - L3 - M - Rend +
1642 S - G - L2 - L3 - HSDir +
1643 S - G - L2 - L3 - Intro +
1645 ExcludeNodes have higher priority than HSLayer3Nodes,
1646 which means that nodes specified in ExcludeNodes will not be
1649 When either this option or HSLayer2Nodes are set, the /16 subnet
1650 and node family restrictions are removed for hidden service
1651 circuits. Additionally, we allow the guard node to be present
1652 as the Rend, HSDir, and IP node, and as the hop before it. This
1653 is done to prevent the adversary from inferring information
1654 about our guard, layer2, and layer3 node choices at later points
1657 This option is meant to be managed by a Tor controller such as
1658 https://github.com/mikeperry-tor/vanguards that selects and
1659 updates this set of nodes for you. Hence it does not do load
1660 balancing if fewer than 20 nodes are selected, and if no nodes in
1661 HSLayer3Nodes are currently available for use, Tor will not work.
1662 Please use extreme care if you are setting this option manually.
1664 [[UseMicrodescriptors]] **UseMicrodescriptors** **0**|**1**|**auto**::
1665 Microdescriptors are a smaller version of the information that Tor needs
1666 in order to build its circuits. Using microdescriptors makes Tor clients
1667 download less directory information, thus saving bandwidth. Directory
1668 caches need to fetch regular descriptors and microdescriptors, so this
1669 option doesn't save any bandwidth for them. For legacy reasons, auto is
1670 accepted, but it has the same effect as 1. (Default: auto)
1672 [[PathBiasCircThreshold]] **PathBiasCircThreshold** __NUM__ +
1674 [[PathBiasNoticeRate]] **PathBiasNoticeRate** __NUM__ +
1676 [[PathBiasWarnRate]] **PathBiasWarnRate** __NUM__ +
1678 [[PathBiasExtremeRate]] **PathBiasExtremeRate** __NUM__ +
1680 [[PathBiasDropGuards]] **PathBiasDropGuards** __NUM__ +
1682 [[PathBiasScaleThreshold]] **PathBiasScaleThreshold** __NUM__::
1683 These options override the default behavior of Tor's (**currently
1684 experimental**) path bias detection algorithm. To try to find broken or
1685 misbehaving guard nodes, Tor looks for nodes where more than a certain
1686 fraction of circuits through that guard fail to get built. +
1688 The PathBiasCircThreshold option controls how many circuits we need to build
1689 through a guard before we make these checks. The PathBiasNoticeRate,
1690 PathBiasWarnRate and PathBiasExtremeRate options control what fraction of
1691 circuits must succeed through a guard so we won't write log messages.
1692 If less than PathBiasExtremeRate circuits succeed *and* PathBiasDropGuards
1693 is set to 1, we disable use of that guard. +
1695 When we have seen more than PathBiasScaleThreshold
1696 circuits through a guard, we scale our observations by 0.5 (governed by
1697 the consensus) so that new observations don't get swamped by old ones. +
1699 By default, or if a negative value is provided for one of these options,
1700 Tor uses reasonable defaults from the networkstatus consensus document.
1701 If no defaults are available there, these options default to 150, .70,
1702 .50, .30, 0, and 300 respectively.
1704 [[PathBiasUseThreshold]] **PathBiasUseThreshold** __NUM__ +
1706 [[PathBiasNoticeUseRate]] **PathBiasNoticeUseRate** __NUM__ +
1708 [[PathBiasExtremeUseRate]] **PathBiasExtremeUseRate** __NUM__ +
1710 [[PathBiasScaleUseThreshold]] **PathBiasScaleUseThreshold** __NUM__::
1711 Similar to the above options, these options override the default behavior
1712 of Tor's (**currently experimental**) path use bias detection algorithm. +
1714 Where as the path bias parameters govern thresholds for successfully
1715 building circuits, these four path use bias parameters govern thresholds
1716 only for circuit usage. Circuits which receive no stream usage
1717 are not counted by this detection algorithm. A used circuit is considered
1718 successful if it is capable of carrying streams or otherwise receiving
1719 well-formed responses to RELAY cells. +
1721 By default, or if a negative value is provided for one of these options,
1722 Tor uses reasonable defaults from the networkstatus consensus document.
1723 If no defaults are available there, these options default to 20, .80,
1724 .60, and 100, respectively.
1726 [[ClientUseIPv4]] **ClientUseIPv4** **0**|**1**::
1727 If this option is set to 0, Tor will avoid connecting to directory servers
1728 and entry nodes over IPv4. Note that clients with an IPv4
1729 address in a **Bridge**, proxy, or pluggable transport line will try
1730 connecting over IPv4 even if **ClientUseIPv4** is set to 0. (Default: 1)
1732 [[ClientUseIPv6]] **ClientUseIPv6** **0**|**1**::
1733 If this option is set to 1, Tor might connect to directory servers or
1734 entry nodes over IPv6. Note that clients configured with an IPv6 address
1735 in a **Bridge**, proxy, or pluggable transport line will try connecting
1736 over IPv6 even if **ClientUseIPv6** is set to 0. (Default: 0)
1738 [[ClientPreferIPv6DirPort]] **ClientPreferIPv6DirPort** **0**|**1**|**auto**::
1739 If this option is set to 1, Tor prefers a directory port with an IPv6
1740 address over one with IPv4, for direct connections, if a given directory
1741 server has both. (Tor also prefers an IPv6 DirPort if IPv4Client is set to
1742 0.) If this option is set to auto, clients prefer IPv4. Other things may
1743 influence the choice. This option breaks a tie to the favor of IPv6.
1744 (Default: auto) (DEPRECATED: This option has had no effect for some
1747 [[ClientPreferIPv6ORPort]] **ClientPreferIPv6ORPort** **0**|**1**|**auto**::
1748 If this option is set to 1, Tor prefers an OR port with an IPv6
1749 address over one with IPv4 if a given entry node has both. (Tor also
1750 prefers an IPv6 ORPort if IPv4Client is set to 0.) If this option is set
1751 to auto, Tor bridge clients prefer the configured bridge address, and
1752 other clients prefer IPv4. Other things may influence the choice. This
1753 option breaks a tie to the favor of IPv6. (Default: auto)
1755 [[PathsNeededToBuildCircuits]] **PathsNeededToBuildCircuits** __NUM__::
1756 Tor clients don't build circuits for user traffic until they know
1757 about enough of the network so that they could potentially construct
1758 enough of the possible paths through the network. If this option
1759 is set to a fraction between 0.25 and 0.95, Tor won't build circuits
1760 until it has enough descriptors or microdescriptors to construct
1761 that fraction of possible paths. Note that setting this option too low
1762 can make your Tor client less anonymous, and setting it too high can
1763 prevent your Tor client from bootstrapping. If this option is negative,
1764 Tor will use a default value chosen by the directory authorities. If the
1765 directory authorities do not choose a value, Tor will default to 0.6.
1768 [[ClientBootstrapConsensusAuthorityDownloadInitialDelay]] **ClientBootstrapConsensusAuthorityDownloadInitialDelay** __N__::
1769 Initial delay in seconds for when clients should download consensuses from authorities
1770 if they are bootstrapping (that is, they don't have a usable, reasonably
1771 live consensus). Only used by clients fetching from a list of fallback
1772 directory mirrors. This schedule is advanced by (potentially concurrent)
1773 connection attempts, unlike other schedules, which are advanced by
1774 connection failures. (Default: 6)
1776 [[ClientBootstrapConsensusFallbackDownloadInitialDelay]] **ClientBootstrapConsensusFallbackDownloadInitialDelay** __N__::
1777 Initial delay in seconds for when clients should download consensuses from fallback
1778 directory mirrors if they are bootstrapping (that is, they don't have a
1779 usable, reasonably live consensus). Only used by clients fetching from a
1780 list of fallback directory mirrors. This schedule is advanced by
1781 (potentially concurrent) connection attempts, unlike other schedules,
1782 which are advanced by connection failures. (Default: 0)
1784 [[ClientBootstrapConsensusAuthorityOnlyDownloadInitialDelay]] **ClientBootstrapConsensusAuthorityOnlyDownloadInitialDelay** __N__::
1785 Initial delay in seconds for when clients should download consensuses from authorities
1786 if they are bootstrapping (that is, they don't have a usable, reasonably
1787 live consensus). Only used by clients which don't have or won't fetch
1788 from a list of fallback directory mirrors. This schedule is advanced by
1789 (potentially concurrent) connection attempts, unlike other schedules,
1790 which are advanced by connection failures. (Default: 0)
1792 [[ClientBootstrapConsensusMaxInProgressTries]] **ClientBootstrapConsensusMaxInProgressTries** __NUM__::
1793 Try this many simultaneous connections to download a consensus before
1794 waiting for one to complete, timeout, or error out. (Default: 3)
1799 The following options are useful only for servers (that is, if ORPort
1802 [[Address]] **Address** __address__::
1803 The IPv4 address of this server, or a fully qualified domain name of
1804 this server that resolves to an IPv4 address. You can leave this
1805 unset, and Tor will try to guess your IPv4 address. This IPv4
1806 address is the one used to tell clients and other servers where to
1807 find your Tor server; it doesn't affect the address that your server
1808 binds to. To bind to a different address, use the ORPort and
1809 OutboundBindAddress options.
1811 [[AssumeReachable]] **AssumeReachable** **0**|**1**::
1812 This option is used when bootstrapping a new Tor network. If set to 1,
1813 don't do self-reachability testing; just upload your server descriptor
1814 immediately. If **AuthoritativeDirectory** is also set, this option
1815 instructs the dirserver to bypass remote reachability testing too and list
1816 all connected servers as running.
1818 [[BridgeRelay]] **BridgeRelay** **0**|**1**::
1819 Sets the relay to act as a "bridge" with respect to relaying connections
1820 from bridge users to the Tor network. It mainly causes Tor to publish a
1821 server descriptor to the bridge database, rather than
1822 to the public directory authorities.
1824 [[BridgeDistribution]] **BridgeDistribution** __string__::
1825 If set along with BridgeRelay, Tor will include a new line in its
1826 bridge descriptor which indicates to the BridgeDB service how it
1827 would like its bridge address to be given out. Set it to "none" if
1828 you want BridgeDB to avoid distributing your bridge address, or "any" to
1829 let BridgeDB decide. (Default: any)
1831 Note: as of Oct 2017, the BridgeDB part of this option is not yet
1832 implemented. Until BridgeDB is updated to obey this option, your
1833 bridge will make this request, but it will not (yet) be obeyed.
1835 [[ContactInfo]] **ContactInfo** __email_address__::
1836 Administrative contact information for this relay or bridge. This line
1837 can be used to contact you if your relay or bridge is misconfigured or
1838 something else goes wrong. Note that we archive and publish all
1839 descriptors containing these lines and that Google indexes them, so
1840 spammers might also collect them. You may want to obscure the fact
1841 that it's an email address and/or generate a new address for this
1844 ContactInfo **must** be set to a working address if you run more than one
1845 relay or bridge. (Really, everybody running a relay or bridge should set
1849 [[ExitRelay]] **ExitRelay** **0**|**1**|**auto**::
1850 Tells Tor whether to run as an exit relay. If Tor is running as a
1851 non-bridge server, and ExitRelay is set to 1, then Tor allows traffic to
1852 exit according to the ExitPolicy option (or the default ExitPolicy if
1853 none is specified). +
1855 If ExitRelay is set to 0, no traffic is allowed to
1856 exit, and the ExitPolicy option is ignored. +
1858 If ExitRelay is set to "auto", then Tor behaves as if it were set to 1, but
1859 warns the user if this would cause traffic to exit. In a future version,
1860 the default value will be 0. (Default: auto)
1862 [[ExitPolicy]] **ExitPolicy** __policy__,__policy__,__...__::
1863 Set an exit policy for this server. Each policy is of the form
1864 "**accept[6]**|**reject[6]** __ADDR__[/__MASK__][:__PORT__]". If /__MASK__ is
1865 omitted then this policy just applies to the host given. Instead of giving
1866 a host or network you can also use "\*" to denote the universe (0.0.0.0/0
1867 and ::/0), or \*4 to denote all IPv4 addresses, and \*6 to denote all IPv6
1869 __PORT__ can be a single port number, an interval of ports
1870 "__FROM_PORT__-__TO_PORT__", or "\*". If __PORT__ is omitted, that means
1873 For example, "accept 18.7.22.69:\*,reject 18.0.0.0/8:\*,accept \*:\*" would
1874 reject any IPv4 traffic destined for MIT except for web.mit.edu, and accept
1875 any other IPv4 or IPv6 traffic. +
1877 Tor also allows IPv6 exit policy entries. For instance, "reject6 [FC00::]/7:\*"
1878 rejects all destinations that share 7 most significant bit prefix with
1879 address FC00::. Respectively, "accept6 [C000::]/3:\*" accepts all destinations
1880 that share 3 most significant bit prefix with address C000::. +
1882 accept6 and reject6 only produce IPv6 exit policy entries. Using an IPv4
1883 address with accept6 or reject6 is ignored and generates a warning.
1884 accept/reject allows either IPv4 or IPv6 addresses. Use \*4 as an IPv4
1885 wildcard address, and \*6 as an IPv6 wildcard address. accept/reject *
1886 expands to matching IPv4 and IPv6 wildcard address rules. +
1888 To specify all IPv4 and IPv6 internal and link-local networks (including
1889 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,
1890 172.16.0.0/12, [::]/8, [FC00::]/7, [FE80::]/10, [FEC0::]/10, [FF00::]/8,
1891 and [::]/127), you can use the "private" alias instead of an address.
1892 ("private" always produces rules for IPv4 and IPv6 addresses, even when
1893 used with accept6/reject6.) +
1895 Private addresses are rejected by default (at the beginning of your exit
1896 policy), along with any configured primary public IPv4 and IPv6 addresses.
1897 These private addresses are rejected unless you set the
1898 ExitPolicyRejectPrivate config option to 0. For example, once you've done
1899 that, you could allow HTTP to 127.0.0.1 and block all other connections to
1900 internal networks with "accept 127.0.0.1:80,reject private:\*", though that
1901 may also allow connections to your own computer that are addressed to its
1902 public (external) IP address. See RFC 1918 and RFC 3330 for more details
1903 about internal and reserved IP address space. See
1904 ExitPolicyRejectLocalInterfaces if you want to block every address on the
1905 relay, even those that aren't advertised in the descriptor. +
1907 This directive can be specified multiple times so you don't have to put it
1910 Policies are considered first to last, and the first match wins. If you
1911 want to allow the same ports on IPv4 and IPv6, write your rules using
1912 accept/reject \*. If you want to allow different ports on IPv4 and IPv6,
1913 write your IPv6 rules using accept6/reject6 \*6, and your IPv4 rules using
1914 accept/reject \*4. If you want to \_replace_ the default exit policy, end
1915 your exit policy with either a reject \*:* or an accept \*:*. Otherwise,
1916 you're \_augmenting_ (prepending to) the default exit policy. +
1918 If you want to use a reduced exit policy rather than the default exit
1919 policy, set "ReducedExitPolicy 1". If you want to _replace_ the default
1920 exit policy with your custom exit policy, end your exit policy with either
1921 a reject *:* or an accept *:*. Otherwise, you're _augmenting_ (prepending
1922 to) the default or reduced exit policy. +
1924 The default exit policy is:
1938 // Anchor only for formatting, not visible in the man page.
1939 [[ExitPolicyDefault]]::
1940 Since the default exit policy uses accept/reject *, it applies to both
1941 IPv4 and IPv6 addresses.
1943 [[ExitPolicyRejectPrivate]] **ExitPolicyRejectPrivate** **0**|**1**::
1944 Reject all private (local) networks, along with the relay's advertised
1945 public IPv4 and IPv6 addresses, at the beginning of your exit policy.
1946 See above entry on ExitPolicy.
1949 [[ExitPolicyRejectLocalInterfaces]] **ExitPolicyRejectLocalInterfaces** **0**|**1**::
1950 Reject all IPv4 and IPv6 addresses that the relay knows about, at the
1951 beginning of your exit policy. This includes any OutboundBindAddress, the
1952 bind addresses of any port options, such as ControlPort or DNSPort, and any
1953 public IPv4 and IPv6 addresses on any interface on the relay. (If IPv6Exit
1954 is not set, all IPv6 addresses will be rejected anyway.)
1955 See above entry on ExitPolicy.
1956 This option is off by default, because it lists all public relay IP
1957 addresses in the ExitPolicy, even those relay operators might prefer not
1961 [[ReducedExitPolicy]] **ReducedExitPolicy** **0**|**1**::
1962 If set, use a reduced exit policy rather than the default one. +
1964 The reduced exit policy is an alternative to the default exit policy. It
1965 allows as many Internet services as possible while still blocking the
1966 majority of TCP ports. Currently, the policy allows approximately 65 ports.
1967 This reduces the odds that your node will be used for peer-to-peer
1970 The reduced exit policy is:
2054 [[IPv6Exit]] **IPv6Exit** **0**|**1**::
2055 If set, and we are an exit node, allow clients to use us for IPv6
2056 traffic. (Default: 0)
2058 [[MaxOnionQueueDelay]] **MaxOnionQueueDelay** __NUM__ [**msec**|**second**]::
2059 If we have more onionskins queued for processing than we can process in
2060 this amount of time, reject new ones. (Default: 1750 msec)
2062 [[MyFamily]] **MyFamily** __fingerprint__,__fingerprint__,...::
2063 Declare that this Tor relay is controlled or administered by a group or
2064 organization identical or similar to that of the other relays, defined by
2065 their (possibly $-prefixed) identity fingerprints.
2066 This option can be repeated many times, for
2067 convenience in defining large families: all fingerprints in all MyFamily
2068 lines are merged into one list.
2069 When two relays both declare that they are in the
2070 same \'family', Tor clients will not use them in the same circuit. (Each
2071 relay only needs to list the other servers in its family; it doesn't need to
2072 list itself, but it won't hurt if it does.) Do not list any bridge relay as it would
2073 compromise its concealment. +
2075 When listing a node, it's better to list it by fingerprint than by
2076 nickname: fingerprints are more reliable. +
2078 If you run more than one relay, the MyFamily option on each relay
2079 **must** list all other relays, as described above.
2081 [[Nickname]] **Nickname** __name__::
2082 Set the server's nickname to \'name'. Nicknames must be between 1 and 19
2083 characters inclusive, and must contain only the characters [a-zA-Z0-9].
2084 If not set, **Unnamed** will be used. Relays can always be uniquely identified
2085 by their identity fingerprints.
2087 [[NumCPUs]] **NumCPUs** __num__::
2088 How many processes to use at once for decrypting onionskins and other
2089 parallelizable operations. If this is set to 0, Tor will try to detect
2090 how many CPUs you have, defaulting to 1 if it can't tell. (Default: 0)
2092 [[ORPort]] **ORPort** \['address':]__PORT__|**auto** [_flags_]::
2093 Advertise this port to listen for connections from Tor clients and
2094 servers. This option is required to be a Tor server.
2095 Set it to "auto" to have Tor pick a port for you. Set it to 0 to not
2096 run an ORPort at all. This option can occur more than once. (Default: 0) +
2098 Tor recognizes these flags on each ORPort:
2100 By default, we bind to a port and tell our users about it. If
2101 NoAdvertise is specified, we don't advertise, but listen anyway. This
2102 can be useful if the port everybody will be connecting to (for
2103 example, one that's opened on our firewall) is somewhere else.
2105 By default, we bind to a port and tell our users about it. If
2106 NoListen is specified, we don't bind, but advertise anyway. This
2107 can be useful if something else (for example, a firewall's port
2108 forwarding configuration) is causing connections to reach us.
2110 If the address is absent, or resolves to both an IPv4 and an IPv6
2111 address, only listen to the IPv4 address.
2113 If the address is absent, or resolves to both an IPv4 and an IPv6
2114 address, only listen to the IPv6 address.
2116 // Anchor only for formatting, not visible in the man page.
2117 [[ORPortFlagsExclusive]]::
2118 For obvious reasons, NoAdvertise and NoListen are mutually exclusive, and
2119 IPv4Only and IPv6Only are mutually exclusive.
2121 [[PublishServerDescriptor]] **PublishServerDescriptor** **0**|**1**|**v3**|**bridge**,**...**::
2122 This option specifies which descriptors Tor will publish when acting as
2124 choose multiple arguments, separated by commas. +
2126 If this option is set to 0, Tor will not publish its
2127 descriptors to any directories. (This is useful if you're testing
2128 out your server, or if you're using a Tor controller that handles
2129 directory publishing for you.) Otherwise, Tor will publish its
2130 descriptors of all type(s) specified. The default is "1", which
2131 means "if running as a relay or bridge, publish descriptors to the
2132 appropriate authorities". Other possibilities are "v3", meaning
2133 "publish as if you're a relay", and "bridge", meaning "publish as
2134 if you're a bridge".
2136 [[ShutdownWaitLength]] **ShutdownWaitLength** __NUM__::
2137 When we get a SIGINT and we're a server, we begin shutting down:
2138 we close listeners and start refusing new circuits. After **NUM**
2139 seconds, we exit. If we get a second SIGINT, we exit immediately.
2140 (Default: 30 seconds)
2142 [[SSLKeyLifetime]] **SSLKeyLifetime** __N__ **minutes**|**hours**|**days**|**weeks**::
2143 When creating a link certificate for our outermost SSL handshake,
2144 set its lifetime to this amount of time. If set to 0, Tor will choose
2145 some reasonable random defaults. (Default: 0)
2147 [[HeartbeatPeriod]] **HeartbeatPeriod** __N__ **minutes**|**hours**|**days**|**weeks**::
2148 Log a heartbeat message every **HeartbeatPeriod** seconds. This is
2149 a log level __notice__ message, designed to let you know your Tor
2150 server is still alive and doing useful things. Settings this
2151 to 0 will disable the heartbeat. Otherwise, it must be at least 30
2152 minutes. (Default: 6 hours)
2154 [[MainloopStats]] **MainloopStats** **0**|**1**::
2155 Log main loop statistics every **HeartbeatPeriod** seconds. This is a log
2156 level __notice__ message designed to help developers instrumenting Tor's
2157 main event loop. (Default: 0)
2159 [[AccountingMax]] **AccountingMax** __N__ **bytes**|**KBytes**|**MBytes**|**GBytes**|**TBytes**|**KBits**|**MBits**|**GBits**|**TBits**::
2160 Limits the max number of bytes sent and received within a set time period
2161 using a given calculation rule (see: AccountingStart, AccountingRule).
2162 Useful if you need to stay under a specific bandwidth. By default, the
2163 number used for calculation is the max of either the bytes sent or
2164 received. For example, with AccountingMax set to 1 GByte, a server
2165 could send 900 MBytes and receive 800 MBytes and continue running.
2166 It will only hibernate once one of the two reaches 1 GByte. This can
2167 be changed to use the sum of the both bytes received and sent by setting
2168 the AccountingRule option to "sum" (total bandwidth in/out). When the
2169 number of bytes remaining gets low, Tor will stop accepting new connections
2170 and circuits. When the number of bytes is exhausted, Tor will hibernate
2171 until some time in the next accounting period. To prevent all servers
2172 from waking at the same time, Tor will also wait until a random point
2173 in each period before waking up. If you have bandwidth cost issues,
2174 enabling hibernation is preferable to setting a low bandwidth, since
2175 it provides users with a collection of fast servers that are up some
2176 of the time, which is more useful than a set of slow servers that are
2179 [[AccountingRule]] **AccountingRule** **sum**|**max**|**in**|**out**::
2180 How we determine when our AccountingMax has been reached (when we
2181 should hibernate) during a time interval. Set to "max" to calculate
2182 using the higher of either the sent or received bytes (this is the
2183 default functionality). Set to "sum" to calculate using the sent
2184 plus received bytes. Set to "in" to calculate using only the
2185 received bytes. Set to "out" to calculate using only the sent bytes.
2188 [[AccountingStart]] **AccountingStart** **day**|**week**|**month** [__day__] __HH:MM__::
2189 Specify how long accounting periods last. If **month** is given,
2190 each accounting period runs from the time __HH:MM__ on the __dayth__ day of one
2191 month to the same day and time of the next. The relay will go at full speed,
2192 use all the quota you specify, then hibernate for the rest of the period. (The
2193 day must be between 1 and 28.) If **week** is given, each accounting period
2194 runs from the time __HH:MM__ of the __dayth__ day of one week to the same day
2195 and time of the next week, with Monday as day 1 and Sunday as day 7. If **day**
2196 is given, each accounting period runs from the time __HH:MM__ each day to the
2197 same time on the next day. All times are local, and given in 24-hour time.
2198 (Default: "month 1 0:00")
2200 [[RefuseUnknownExits]] **RefuseUnknownExits** **0**|**1**|**auto**::
2201 Prevent nodes that don't appear in the consensus from exiting using this
2202 relay. If the option is 1, we always block exit attempts from such
2203 nodes; if it's 0, we never do, and if the option is "auto", then we do
2204 whatever the authorities suggest in the consensus (and block if the consensus
2205 is quiet on the issue). (Default: auto)
2207 [[ServerDNSResolvConfFile]] **ServerDNSResolvConfFile** __filename__::
2208 Overrides the default DNS configuration with the configuration in
2209 __filename__. The file format is the same as the standard Unix
2210 "**resolv.conf**" file (7). This option, like all other ServerDNS options,
2211 only affects name lookups that your server does on behalf of clients.
2212 (Defaults to use the system DNS configuration.)
2214 [[ServerDNSAllowBrokenConfig]] **ServerDNSAllowBrokenConfig** **0**|**1**::
2215 If this option is false, Tor exits immediately if there are problems
2216 parsing the system DNS configuration or connecting to nameservers.
2217 Otherwise, Tor continues to periodically retry the system nameservers until
2218 it eventually succeeds. (Default: 1)
2220 [[ServerDNSSearchDomains]] **ServerDNSSearchDomains** **0**|**1**::
2221 If set to 1, then we will search for addresses in the local search domain.
2222 For example, if this system is configured to believe it is in
2223 "example.com", and a client tries to connect to "www", the client will be
2224 connected to "www.example.com". This option only affects name lookups that
2225 your server does on behalf of clients. (Default: 0)
2227 [[ServerDNSDetectHijacking]] **ServerDNSDetectHijacking** **0**|**1**::
2228 When this option is set to 1, we will test periodically to determine
2229 whether our local nameservers have been configured to hijack failing DNS
2230 requests (usually to an advertising site). If they are, we will attempt to
2231 correct this. This option only affects name lookups that your server does
2232 on behalf of clients. (Default: 1)
2234 [[ServerDNSTestAddresses]] **ServerDNSTestAddresses** __hostname__,__hostname__,__...__::
2235 When we're detecting DNS hijacking, make sure that these __valid__ addresses
2236 aren't getting redirected. If they are, then our DNS is completely useless,
2237 and we'll reset our exit policy to "reject \*:*". This option only affects
2238 name lookups that your server does on behalf of clients. (Default:
2239 "www.google.com, www.mit.edu, www.yahoo.com, www.slashdot.org")
2241 [[ServerDNSAllowNonRFC953Hostnames]] **ServerDNSAllowNonRFC953Hostnames** **0**|**1**::
2242 When this option is disabled, Tor does not try to resolve hostnames
2243 containing illegal characters (like @ and :) rather than sending them to an
2244 exit node to be resolved. This helps trap accidental attempts to resolve
2245 URLs and so on. This option only affects name lookups that your server does
2246 on behalf of clients. (Default: 0)
2248 [[BridgeRecordUsageByCountry]] **BridgeRecordUsageByCountry** **0**|**1**::
2249 When this option is enabled and BridgeRelay is also enabled, and we have
2250 GeoIP data, Tor keeps a per-country count of how many client
2251 addresses have contacted it so that it can help the bridge authority guess
2252 which countries have blocked access to it. (Default: 1)
2254 [[ServerDNSRandomizeCase]] **ServerDNSRandomizeCase** **0**|**1**::
2255 When this option is set, Tor sets the case of each character randomly in
2256 outgoing DNS requests, and makes sure that the case matches in DNS replies.
2257 This so-called "0x20 hack" helps resist some types of DNS poisoning attack.
2258 For more information, see "Increased DNS Forgery Resistance through
2259 0x20-Bit Encoding". This option only affects name lookups that your server
2260 does on behalf of clients. (Default: 1)
2262 [[GeoIPFile]] **GeoIPFile** __filename__::
2263 A filename containing IPv4 GeoIP data, for use with by-country statistics.
2265 [[GeoIPv6File]] **GeoIPv6File** __filename__::
2266 A filename containing IPv6 GeoIP data, for use with by-country statistics.
2268 [[CellStatistics]] **CellStatistics** **0**|**1**::
2270 When this option is enabled, Tor collects statistics about cell
2271 processing (i.e. mean time a cell is spending in a queue, mean
2272 number of cells in a queue and mean number of processed cells per
2273 circuit) and writes them into disk every 24 hours. Onion router
2274 operators may use the statistics for performance monitoring.
2275 If ExtraInfoStatistics is enabled, it will published as part of
2276 extra-info document. (Default: 0)
2278 [[PaddingStatistics]] **PaddingStatistics** **0**|**1**::
2280 When this option is enabled, Tor collects statistics for padding cells
2281 sent and received by this relay, in addition to total cell counts.
2282 These statistics are rounded, and omitted if traffic is low. This
2283 information is important for load balancing decisions related to padding.
2284 If ExtraInfoStatistics is enabled, it will be published
2285 as a part of extra-info document. (Default: 1)
2287 [[DirReqStatistics]] **DirReqStatistics** **0**|**1**::
2288 Relays and bridges only.
2289 When this option is enabled, a Tor directory writes statistics on the
2290 number and response time of network status requests to disk every 24
2291 hours. Enables relay and bridge operators to monitor how much their
2292 server is being used by clients to learn about Tor network.
2293 If ExtraInfoStatistics is enabled, it will published as part of
2294 extra-info document. (Default: 1)
2296 [[EntryStatistics]] **EntryStatistics** **0**|**1**::
2298 When this option is enabled, Tor writes statistics on the number of
2299 directly connecting clients to disk every 24 hours. Enables relay
2300 operators to monitor how much inbound traffic that originates from
2301 Tor clients passes through their server to go further down the
2302 Tor network. If ExtraInfoStatistics is enabled, it will be published
2303 as part of extra-info document. (Default: 0)
2305 [[ExitPortStatistics]] **ExitPortStatistics** **0**|**1**::
2307 When this option is enabled, Tor writes statistics on the number of
2308 relayed bytes and opened stream per exit port to disk every 24 hours.
2309 Enables exit relay operators to measure and monitor amounts of traffic
2310 that leaves Tor network through their exit node. If ExtraInfoStatistics
2311 is enabled, it will be published as part of extra-info document.
2314 [[ConnDirectionStatistics]] **ConnDirectionStatistics** **0**|**1**::
2316 When this option is enabled, Tor writes statistics on the amounts of
2317 traffic it passes between itself and other relays to disk every 24
2318 hours. Enables relay operators to monitor how much their relay is
2319 being used as middle node in the circuit. If ExtraInfoStatistics is
2320 enabled, it will be published as part of extra-info document.
2323 [[HiddenServiceStatistics]] **HiddenServiceStatistics** **0**|**1**::
2325 When this option is enabled, a Tor relay writes obfuscated
2326 statistics on its role as hidden-service directory, introduction
2327 point, or rendezvous point to disk every 24 hours. If
2328 ExtraInfoStatistics is also enabled, these statistics are further
2329 published to the directory authorities. (Default: 1)
2331 [[ExtraInfoStatistics]] **ExtraInfoStatistics** **0**|**1**::
2332 When this option is enabled, Tor includes previously gathered statistics in
2333 its extra-info documents that it uploads to the directory authorities.
2336 [[ExtendAllowPrivateAddresses]] **ExtendAllowPrivateAddresses** **0**|**1**::
2337 When this option is enabled, Tor will connect to relays on localhost,
2338 RFC1918 addresses, and so on. In particular, Tor will make direct OR
2339 connections, and Tor routers allow EXTEND requests, to these private
2340 addresses. (Tor will always allow connections to bridges, proxies, and
2341 pluggable transports configured on private addresses.) Enabling this
2342 option can create security issues; you should probably leave it off.
2345 [[MaxMemInQueues]] **MaxMemInQueues** __N__ **bytes**|**KB**|**MB**|**GB**::
2346 This option configures a threshold above which Tor will assume that it
2347 needs to stop queueing or buffering data because it's about to run out of
2348 memory. If it hits this threshold, it will begin killing circuits until
2349 it has recovered at least 10% of this memory. Do not set this option too
2350 low, or your relay may be unreliable under load. This option only
2351 affects some queues, so the actual process size will be larger than
2352 this. If this option is set to 0, Tor will try to pick a reasonable
2353 default based on your system's physical memory. (Default: 0)
2355 [[DisableOOSCheck]] **DisableOOSCheck** **0**|**1**::
2356 This option disables the code that closes connections when Tor notices
2357 that it is running low on sockets. Right now, it is on by default,
2358 since the existing out-of-sockets mechanism tends to kill OR connections
2359 more than it should. (Default: 1)
2361 [[SigningKeyLifetime]] **SigningKeyLifetime** __N__ **days**|**weeks**|**months**::
2362 For how long should each Ed25519 signing key be valid? Tor uses a
2363 permanent master identity key that can be kept offline, and periodically
2364 generates new "signing" keys that it uses online. This option
2365 configures their lifetime.
2368 [[OfflineMasterKey]] **OfflineMasterKey** **0**|**1**::
2369 If non-zero, the Tor relay will never generate or load its master secret
2370 key. Instead, you'll have to use "tor --keygen" to manage the permanent
2371 ed25519 master identity key, as well as the corresponding temporary
2372 signing keys and certificates. (Default: 0)
2374 [[KeyDirectory]] **KeyDirectory** __DIR__::
2375 Store secret keys in DIR. Can not be changed while tor is
2377 (Default: the "keys" subdirectory of DataDirectory.)
2379 [[KeyDirectoryGroupReadable]] **KeyDirectoryGroupReadable** **0**|**1**::
2380 If this option is set to 0, don't allow the filesystem group to read the
2381 KeywDirectory. If the option is set to 1, make the KeyDirectory readable
2382 by the default GID. (Default: 0)
2384 [[RephistTrackTime]] **RephistTrackTime** __N__ **seconds**|**minutes**|**hours**|**days**|**weeks**::
2385 Tells an authority, or other node tracking node reliability and history,
2386 that fine-grained information about nodes can be discarded when it hasn't
2387 changed for a given amount of time. (Default: 24 hours)
2390 DIRECTORY SERVER OPTIONS
2391 ------------------------
2393 The following options are useful only for directory servers. (Relays with
2394 enough bandwidth automatically become directory servers; see DirCache for
2397 [[DirPortFrontPage]] **DirPortFrontPage** __FILENAME__::
2398 When this option is set, it takes an HTML file and publishes it as "/" on
2399 the DirPort. Now relay operators can provide a disclaimer without needing
2400 to set up a separate webserver. There's a sample disclaimer in
2401 contrib/operator-tools/tor-exit-notice.html.
2403 [[DirPort]] **DirPort** \['address':]__PORT__|**auto** [_flags_]::
2404 If this option is nonzero, advertise the directory service on this port.
2405 Set it to "auto" to have Tor pick a port for you. This option can occur
2406 more than once, but only one advertised DirPort is supported: all
2407 but one DirPort must have the **NoAdvertise** flag set. (Default: 0) +
2409 The same flags are supported here as are supported by ORPort.
2411 [[DirPolicy]] **DirPolicy** __policy__,__policy__,__...__::
2412 Set an entrance policy for this server, to limit who can connect to the
2413 directory ports. The policies have the same form as exit policies above,
2414 except that port specifiers are ignored. Any address not matched by
2415 some entry in the policy is accepted.
2417 [[DirCache]] **DirCache** **0**|**1**::
2418 When this option is set, Tor caches all current directory documents except
2419 extra info documents, and accepts client requests for them. If
2420 **DownloadExtraInfo** is set, cached extra info documents are also cached.
2421 Setting **DirPort** is not required for **DirCache**, because clients
2422 connect via the ORPort by default. Setting either DirPort or BridgeRelay
2423 and setting DirCache to 0 is not supported. (Default: 1)
2425 [[MaxConsensusAgeForDiffs]] **MaxConsensusAgeForDiffs** __N__ **minutes**|**hours**|**days**|**weeks**::
2426 When this option is nonzero, Tor caches will not try to generate
2427 consensus diffs for any consensus older than this amount of time.
2428 If this option is set to zero, Tor will pick a reasonable default from
2429 the current networkstatus document. You should not set this
2430 option unless your cache is severely low on disk space or CPU.
2431 If you need to set it, keeping it above 3 or 4 hours will help clients
2432 much more than setting it to zero.
2436 DENIAL OF SERVICE MITIGATION OPTIONS
2437 ------------------------------------
2439 Tor has three built-in mitigation options that can be individually
2440 enabled/disabled and fine-tuned, but by default Tor directory authorities will
2441 define reasonable values for relays and no explicit configuration is required
2442 to make use of these protections. The mitigations take place at relays,
2445 1. If a single client address makes too many concurrent connections (this is
2446 configurable via DoSConnectionMaxConcurrentCount), hang up on further
2449 2. If a single client IP address (v4 or v6) makes circuits too quickly
2450 (default values are more than 3 per second, with an allowed burst of 90,
2451 see DoSCircuitCreationRate and DoSCircuitCreationBurst) while also having
2452 too many connections open (default is 3, see
2453 DoSCircuitCreationMinConnections), tor will refuse any new circuit (CREATE
2454 cells) for the next while (random value between 1 and 2 hours).
2456 3. If a client asks to establish a rendezvous point to you directly (ex:
2457 Tor2Web client), ignore the request.
2459 These defenses can be manually controlled by torrc options, but relays will
2460 also take guidance from consensus parameters using these same names, so there's
2461 no need to configure anything manually. In doubt, do not change those values.
2463 The values set by the consensus, if any, can be found here:
2464 https://consensus-health.torproject.org/#consensusparams
2466 If any of the DoS mitigations are enabled, a heartbeat message will appear in
2467 your log at NOTICE level which looks like:
2469 DoS mitigation since startup: 429042 circuits rejected, 17 marked addresses.
2470 2238 connections closed. 8052 single hop clients refused.
2472 The following options are useful only for a public relay. They control the
2473 Denial of Service mitigation subsystem described above.
2475 [[DoSCircuitCreationEnabled]] **DoSCircuitCreationEnabled** **0**|**1**|**auto**::
2477 Enable circuit creation DoS mitigation. If set to 1 (enabled), tor will
2478 cache client IPs along with statistics in order to detect circuit DoS
2479 attacks. If an address is positively identified, tor will activate
2480 defenses against the address. See the DoSCircuitCreationDefenseType option
2481 for more details. This is a client to relay detection only. "auto" means
2482 use the consensus parameter. If not defined in the consensus, the value is 0.
2485 [[DoSCircuitCreationMinConnections]] **DoSCircuitCreationMinConnections** __NUM__::
2487 Minimum threshold of concurrent connections before a client address can be
2488 flagged as executing a circuit creation DoS. In other words, once a client
2489 address reaches the circuit rate and has a minimum of NUM concurrent
2490 connections, a detection is positive. "0" means use the consensus
2491 parameter. If not defined in the consensus, the value is 3.
2494 [[DoSCircuitCreationRate]] **DoSCircuitCreationRate** __NUM__::
2496 The allowed circuit creation rate per second applied per client IP
2497 address. If this option is 0, it obeys a consensus parameter. If not
2498 defined in the consensus, the value is 3.
2501 [[DoSCircuitCreationBurst]] **DoSCircuitCreationBurst** __NUM__::
2503 The allowed circuit creation burst per client IP address. If the circuit
2504 rate and the burst are reached, a client is marked as executing a circuit
2505 creation DoS. "0" means use the consensus parameter. If not defined in the
2506 consensus, the value is 90.
2509 [[DoSCircuitCreationDefenseType]] **DoSCircuitCreationDefenseType** __NUM__::
2511 This is the type of defense applied to a detected client address. The
2512 possible values are:
2516 2: Refuse circuit creation for the DoSCircuitCreationDefenseTimePeriod period of time.
2518 "0" means use the consensus parameter. If not defined in the consensus, the value is 2.
2521 [[DoSCircuitCreationDefenseTimePeriod]] **DoSCircuitCreationDefenseTimePeriod** __N__ **seconds**|**minutes**|**hours**::
2523 The base time period in seconds that the DoS defense is activated for. The
2524 actual value is selected randomly for each activation from N+1 to 3/2 * N.
2525 "0" means use the consensus parameter. If not defined in the consensus,
2526 the value is 3600 seconds (1 hour).
2529 [[DoSConnectionEnabled]] **DoSConnectionEnabled** **0**|**1**|**auto**::
2531 Enable the connection DoS mitigation. If set to 1 (enabled), for client
2532 address only, this allows tor to mitigate against large number of
2533 concurrent connections made by a single IP address. "auto" means use the
2534 consensus parameter. If not defined in the consensus, the value is 0.
2537 [[DoSConnectionMaxConcurrentCount]] **DoSConnectionMaxConcurrentCount** __NUM__::
2539 The maximum threshold of concurrent connection from a client IP address.
2540 Above this limit, a defense selected by DoSConnectionDefenseType is
2541 applied. "0" means use the consensus parameter. If not defined in the
2542 consensus, the value is 100.
2545 [[DoSConnectionDefenseType]] **DoSConnectionDefenseType** __NUM__::
2547 This is the type of defense applied to a detected client address for the
2548 connection mitigation. The possible values are:
2552 2: Immediately close new connections.
2554 "0" means use the consensus parameter. If not defined in the consensus, the value is 2.
2557 [[DoSRefuseSingleHopClientRendezvous]] **DoSRefuseSingleHopClientRendezvous** **0**|**1**|**auto**::
2559 Refuse establishment of rendezvous points for single hop clients. In other
2560 words, if a client directly connects to the relay and sends an
2561 ESTABLISH_RENDEZVOUS cell, it is silently dropped. "auto" means use the
2562 consensus parameter. If not defined in the consensus, the value is 0.
2566 DIRECTORY AUTHORITY SERVER OPTIONS
2567 ----------------------------------
2569 The following options enable operation as a directory authority, and
2570 control how Tor behaves as a directory authority. You should not need
2571 to adjust any of them if you're running a regular relay or exit server
2572 on the public Tor network.
2574 [[AuthoritativeDirectory]] **AuthoritativeDirectory** **0**|**1**::
2575 When this option is set to 1, Tor operates as an authoritative directory
2576 server. Instead of caching the directory, it generates its own list of
2577 good servers, signs it, and sends that to the clients. Unless the clients
2578 already have you listed as a trusted directory, you probably do not want
2581 [[V3AuthoritativeDirectory]] **V3AuthoritativeDirectory** **0**|**1**::
2582 When this option is set in addition to **AuthoritativeDirectory**, Tor
2583 generates version 3 network statuses and serves descriptors, etc as
2584 described in dir-spec.txt file of https://spec.torproject.org/[torspec]
2585 (for Tor clients and servers running at least 0.2.0.x).
2587 [[VersioningAuthoritativeDirectory]] **VersioningAuthoritativeDirectory** **0**|**1**::
2588 When this option is set to 1, Tor adds information on which versions of
2589 Tor are still believed safe for use to the published directory. Each
2590 version 1 authority is automatically a versioning authority; version 2
2591 authorities provide this service optionally. See **RecommendedVersions**,
2592 **RecommendedClientVersions**, and **RecommendedServerVersions**.
2594 [[RecommendedVersions]] **RecommendedVersions** __STRING__::
2595 STRING is a comma-separated list of Tor versions currently believed to be
2596 safe. The list is included in each directory, and nodes which pull down the
2597 directory learn whether they need to upgrade. This option can appear
2598 multiple times: the values from multiple lines are spliced together. When
2599 this is set then **VersioningAuthoritativeDirectory** should be set too.
2601 [[RecommendedPackages]] **RecommendedPackages** __PACKAGENAME__ __VERSION__ __URL__ __DIGESTTYPE__**=**__DIGEST__ ::
2602 Adds "package" line to the directory authority's vote. This information
2603 is used to vote on the correct URL and digest for the released versions
2604 of different Tor-related packages, so that the consensus can certify
2605 them. This line may appear any number of times.
2607 [[RecommendedClientVersions]] **RecommendedClientVersions** __STRING__::
2608 STRING is a comma-separated list of Tor versions currently believed to be
2609 safe for clients to use. This information is included in version 2
2610 directories. If this is not set then the value of **RecommendedVersions**
2611 is used. When this is set then **VersioningAuthoritativeDirectory** should
2614 [[BridgeAuthoritativeDir]] **BridgeAuthoritativeDir** **0**|**1**::
2615 When this option is set in addition to **AuthoritativeDirectory**, Tor
2616 accepts and serves server descriptors, but it caches and serves the main
2617 networkstatus documents rather than generating its own. (Default: 0)
2619 [[MinUptimeHidServDirectoryV2]] **MinUptimeHidServDirectoryV2** __N__ **seconds**|**minutes**|**hours**|**days**|**weeks**::
2620 Minimum uptime of a v2 hidden service directory to be accepted as such by
2621 authoritative directories. (Default: 25 hours)
2623 [[RecommendedServerVersions]] **RecommendedServerVersions** __STRING__::
2624 STRING is a comma-separated list of Tor versions currently believed to be
2625 safe for servers to use. This information is included in version 2
2626 directories. If this is not set then the value of **RecommendedVersions**
2627 is used. When this is set then **VersioningAuthoritativeDirectory** should
2630 [[ConsensusParams]] **ConsensusParams** __STRING__::
2631 STRING is a space-separated list of key=value pairs that Tor will include
2632 in the "params" line of its networkstatus vote.
2634 [[DirAllowPrivateAddresses]] **DirAllowPrivateAddresses** **0**|**1**::
2635 If set to 1, Tor will accept server descriptors with arbitrary "Address"
2636 elements. Otherwise, if the address is not an IP address or is a private IP
2637 address, it will reject the server descriptor. Additionally, Tor
2638 will allow exit policies for private networks to fulfill Exit flag
2639 requirements. (Default: 0)
2641 [[AuthDirBadExit]] **AuthDirBadExit** __AddressPattern...__::
2642 Authoritative directories only. A set of address patterns for servers that
2643 will be listed as bad exits in any network status document this authority
2644 publishes, if **AuthDirListBadExits** is set. +
2646 (The address pattern syntax here and in the options below
2647 is the same as for exit policies, except that you don't need to say
2648 "accept" or "reject", and ports are not needed.)
2650 [[AuthDirInvalid]] **AuthDirInvalid** __AddressPattern...__::
2651 Authoritative directories only. A set of address patterns for servers that
2652 will never be listed as "valid" in any network status document that this
2653 authority publishes.
2655 [[AuthDirReject]] **AuthDirReject** __AddressPattern__...::
2656 Authoritative directories only. A set of address patterns for servers that
2657 will never be listed at all in any network status document that this
2658 authority publishes, or accepted as an OR address in any descriptor
2659 submitted for publication by this authority.
2661 [[AuthDirBadExitCCs]] **AuthDirBadExitCCs** __CC__,... +
2663 [[AuthDirInvalidCCs]] **AuthDirInvalidCCs** __CC__,... +
2665 [[AuthDirRejectCCs]] **AuthDirRejectCCs** __CC__,...::
2666 Authoritative directories only. These options contain a comma-separated
2667 list of country codes such that any server in one of those country codes
2668 will be marked as a bad exit/invalid for use, or rejected
2671 [[AuthDirListBadExits]] **AuthDirListBadExits** **0**|**1**::
2672 Authoritative directories only. If set to 1, this directory has some
2673 opinion about which nodes are unsuitable as exit nodes. (Do not set this to
2674 1 unless you plan to list non-functioning exits as bad; otherwise, you are
2675 effectively voting in favor of every declared exit as an exit.)
2677 [[AuthDirMaxServersPerAddr]] **AuthDirMaxServersPerAddr** __NUM__::
2678 Authoritative directories only. The maximum number of servers that we will
2679 list as acceptable on a single IP address. Set this to "0" for "no limit".
2682 [[AuthDirFastGuarantee]] **AuthDirFastGuarantee** __N__ **bytes**|**KBytes**|**MBytes**|**GBytes**|**TBytes**|**KBits**|**MBits**|**GBits**|**TBits**::
2683 Authoritative directories only. If non-zero, always vote the
2684 Fast flag for any relay advertising this amount of capacity or
2685 more. (Default: 100 KBytes)
2687 [[AuthDirGuardBWGuarantee]] **AuthDirGuardBWGuarantee** __N__ **bytes**|**KBytes**|**MBytes**|**GBytes**|**TBytes**|**KBits**|**MBits**|**GBits**|**TBits**::
2688 Authoritative directories only. If non-zero, this advertised capacity
2689 or more is always sufficient to satisfy the bandwidth requirement
2690 for the Guard flag. (Default: 2 MBytes)
2692 [[AuthDirPinKeys]] **AuthDirPinKeys** **0**|**1**::
2693 Authoritative directories only. If non-zero, do not allow any relay to
2694 publish a descriptor if any other relay has reserved its <Ed25519,RSA>
2695 identity keypair. In all cases, Tor records every keypair it accepts
2696 in a journal if it is new, or if it differs from the most recently
2697 accepted pinning for one of the keys it contains. (Default: 1)
2699 [[AuthDirSharedRandomness]] **AuthDirSharedRandomness** **0**|**1**::
2700 Authoritative directories only. Switch for the shared random protocol.
2701 If zero, the authority won't participate in the protocol. If non-zero
2702 (default), the flag "shared-rand-participate" is added to the authority
2703 vote indicating participation in the protocol. (Default: 1)
2705 [[AuthDirTestEd25519LinkKeys]] **AuthDirTestEd25519LinkKeys** **0**|**1**::
2706 Authoritative directories only. If this option is set to 0, then we treat
2707 relays as "Running" if their RSA key is correct when we probe them,
2708 regardless of their Ed25519 key. We should only ever set this option to 0
2709 if there is some major bug in Ed25519 link authentication that causes us
2710 to label all the relays as not Running. (Default: 1)
2712 [[BridgePassword]] **BridgePassword** __Password__::
2713 If set, contains an HTTP authenticator that tells a bridge authority to
2714 serve all requested bridge information. Used by the (only partially
2715 implemented) "bridge community" design, where a community of bridge
2716 relay operators all use an alternate bridge directory authority,
2717 and their target user audience can periodically fetch the list of
2718 available community bridges to stay up-to-date. (Default: not set)
2720 [[V3AuthVotingInterval]] **V3AuthVotingInterval** __N__ **minutes**|**hours**::
2721 V3 authoritative directories only. Configures the server's preferred voting
2722 interval. Note that voting will __actually__ happen at an interval chosen
2723 by consensus from all the authorities' preferred intervals. This time
2724 SHOULD divide evenly into a day. (Default: 1 hour)
2726 [[V3AuthVoteDelay]] **V3AuthVoteDelay** __N__ **minutes**|**hours**::
2727 V3 authoritative directories only. Configures the server's preferred delay
2728 between publishing its vote and assuming it has all the votes from all the
2729 other authorities. Note that the actual time used is not the server's
2730 preferred time, but the consensus of all preferences. (Default: 5 minutes)
2732 [[V3AuthDistDelay]] **V3AuthDistDelay** __N__ **minutes**|**hours**::
2733 V3 authoritative directories only. Configures the server's preferred delay
2734 between publishing its consensus and signature and assuming it has all the
2735 signatures from all the other authorities. Note that the actual time used
2736 is not the server's preferred time, but the consensus of all preferences.
2737 (Default: 5 minutes)
2739 [[V3AuthNIntervalsValid]] **V3AuthNIntervalsValid** __NUM__::
2740 V3 authoritative directories only. Configures the number of VotingIntervals
2741 for which each consensus should be valid for. Choosing high numbers
2742 increases network partitioning risks; choosing low numbers increases
2743 directory traffic. Note that the actual number of intervals used is not the
2744 server's preferred number, but the consensus of all preferences. Must be at
2745 least 2. (Default: 3)
2747 [[V3BandwidthsFile]] **V3BandwidthsFile** __FILENAME__::
2748 V3 authoritative directories only. Configures the location of the
2749 bandwidth-authority generated file storing information on relays' measured
2750 bandwidth capacities. (Default: unset)
2752 [[V3AuthUseLegacyKey]] **V3AuthUseLegacyKey** **0**|**1**::
2753 If set, the directory authority will sign consensuses not only with its
2754 own signing key, but also with a "legacy" key and certificate with a
2755 different identity. This feature is used to migrate directory authority
2756 keys in the event of a compromise. (Default: 0)
2758 [[AuthDirHasIPv6Connectivity]] **AuthDirHasIPv6Connectivity** **0**|**1**::
2759 Authoritative directories only. When set to 0, OR ports with an
2760 IPv6 address are not included in the authority's votes. When set to 1,
2761 IPv6 OR ports are tested for reachability like IPv4 OR ports. If the
2762 reachability test succeeds, the authority votes for the IPv6 ORPort, and
2763 votes Running for the relay. If the reachability test fails, the authority
2764 does not vote for the IPv6 ORPort, and does not vote Running (Default: 0) +
2766 The content of the consensus depends on the number of voting authorities
2767 that set AuthDirHasIPv6Connectivity:
2769 If no authorities set AuthDirHasIPv6Connectivity 1, there will be no
2770 IPv6 ORPorts in the consensus.
2772 If a minority of authorities set AuthDirHasIPv6Connectivity 1,
2773 unreachable IPv6 ORPorts will be removed from the consensus. But the
2774 majority of IPv4-only authorities will still vote the relay as Running.
2775 Reachable IPv6 ORPort lines will be included in the consensus
2777 If a majority of voting authorities set AuthDirHasIPv6Connectivity 1,
2778 relays with unreachable IPv6 ORPorts will not be listed as Running.
2779 Reachable IPv6 ORPort lines will be included in the consensus
2780 (To ensure that any valid majority will vote relays with unreachable
2781 IPv6 ORPorts not Running, 75% of authorities must set
2782 AuthDirHasIPv6Connectivity 1.)
2784 [[MinMeasuredBWsForAuthToIgnoreAdvertised]] **MinMeasuredBWsForAuthToIgnoreAdvertised** __N__::
2785 A total value, in abstract bandwidth units, describing how much
2786 measured total bandwidth an authority should have observed on the network
2787 before it will treat advertised bandwidths as wholly
2788 unreliable. (Default: 500)
2790 HIDDEN SERVICE OPTIONS
2791 ----------------------
2793 The following options are used to configure a hidden service.
2795 [[HiddenServiceDir]] **HiddenServiceDir** __DIRECTORY__::
2796 Store data files for a hidden service in DIRECTORY. Every hidden service
2797 must have a separate directory. You may use this option multiple times to
2798 specify multiple services. If DIRECTORY does not exist, Tor will create it.
2799 (Note: in current versions of Tor, if DIRECTORY is a relative path,
2800 it will be relative to the current
2801 working directory of Tor instance, not to its DataDirectory. Do not
2802 rely on this behavior; it is not guaranteed to remain the same in future
2805 [[HiddenServicePort]] **HiddenServicePort** __VIRTPORT__ [__TARGET__]::
2806 Configure a virtual port VIRTPORT for a hidden service. You may use this
2807 option multiple times; each time applies to the service using the most
2808 recent HiddenServiceDir. By default, this option maps the virtual port to
2809 the same port on 127.0.0.1 over TCP. You may override the target port,
2810 address, or both by specifying a target of addr, port, addr:port, or
2811 **unix:**__path__. (You can specify an IPv6 target as [addr]:port. Unix
2812 paths may be quoted, and may use standard C escapes.)
2813 You may also have multiple lines with the same VIRTPORT: when a user
2814 connects to that VIRTPORT, one of the TARGETs from those lines will be
2817 [[PublishHidServDescriptors]] **PublishHidServDescriptors** **0**|**1**::
2818 If set to 0, Tor will run any hidden services you configure, but it won't
2819 advertise them to the rendezvous directory. This option is only useful if
2820 you're using a Tor controller that handles hidserv publishing for you.
2823 [[HiddenServiceVersion]] **HiddenServiceVersion** **2**|**3**::
2824 A list of rendezvous service descriptor versions to publish for the hidden
2825 service. Currently, versions 2 and 3 are supported. (Default: 2)
2827 [[HiddenServiceAuthorizeClient]] **HiddenServiceAuthorizeClient** __auth-type__ __client-name__,__client-name__,__...__::
2828 If configured, the hidden service is accessible for authorized clients
2829 only. The auth-type can either be \'basic' for a general-purpose
2830 authorization protocol or \'stealth' for a less scalable protocol that also
2831 hides service activity from unauthorized clients. Only clients that are
2832 listed here are authorized to access the hidden service. Valid client names
2833 are 1 to 16 characters long and only use characters in A-Za-z0-9+-_ (no
2834 spaces). If this option is set, the hidden service is not accessible for
2835 clients without authorization any more. Generated authorization data can be
2836 found in the hostname file. Clients need to put this authorization data in
2837 their configuration file using **HidServAuth**. This option is only for v2
2840 [[HiddenServiceAllowUnknownPorts]] **HiddenServiceAllowUnknownPorts** **0**|**1**::
2841 If set to 1, then connections to unrecognized ports do not cause the
2842 current hidden service to close rendezvous circuits. (Setting this to 0 is
2843 not an authorization mechanism; it is instead meant to be a mild
2844 inconvenience to port-scanners.) (Default: 0)
2846 [[HiddenServiceMaxStreams]] **HiddenServiceMaxStreams** __N__::
2847 The maximum number of simultaneous streams (connections) per rendezvous
2848 circuit. The maximum value allowed is 65535. (Setting this to 0 will allow
2849 an unlimited number of simultaneous streams.) (Default: 0)
2851 [[HiddenServiceMaxStreamsCloseCircuit]] **HiddenServiceMaxStreamsCloseCircuit** **0**|**1**::
2852 If set to 1, then exceeding **HiddenServiceMaxStreams** will cause the
2853 offending rendezvous circuit to be torn down, as opposed to stream creation
2854 requests that exceed the limit being silently ignored. (Default: 0)
2856 [[RendPostPeriod]] **RendPostPeriod** __N__ **seconds**|**minutes**|**hours**|**days**|**weeks**::
2857 Every time the specified period elapses, Tor uploads any rendezvous
2858 service descriptors to the directory servers. This information is also
2859 uploaded whenever it changes. Minimum value allowed is 10 minutes and
2860 maximum is 3.5 days. This option is only for v2 services.
2863 [[HiddenServiceDirGroupReadable]] **HiddenServiceDirGroupReadable** **0**|**1**::
2864 If this option is set to 1, allow the filesystem group to read the
2865 hidden service directory and hostname file. If the option is set to 0,
2866 only owner is able to read the hidden service directory. (Default: 0)
2867 Has no effect on Windows.
2869 [[HiddenServiceNumIntroductionPoints]] **HiddenServiceNumIntroductionPoints** __NUM__::
2870 Number of introduction points the hidden service will have. You can't
2871 have more than 10 for v2 service and 20 for v3. (Default: 3)
2873 [[HiddenServiceSingleHopMode]] **HiddenServiceSingleHopMode** **0**|**1**::
2874 **Experimental - Non Anonymous** Hidden Services on a tor instance in
2875 HiddenServiceSingleHopMode make one-hop (direct) circuits between the onion
2876 service server, and the introduction and rendezvous points. (Onion service
2877 descriptors are still posted using 3-hop paths, to avoid onion service
2878 directories blocking the service.)
2879 This option makes every hidden service instance hosted by a tor instance a
2880 Single Onion Service. One-hop circuits make Single Onion servers easily
2881 locatable, but clients remain location-anonymous. However, the fact that a
2882 client is accessing a Single Onion rather than a Hidden Service may be
2883 statistically distinguishable. +
2885 **WARNING:** Once a hidden service directory has been used by a tor
2886 instance in HiddenServiceSingleHopMode, it can **NEVER** be used again for
2887 a hidden service. It is best practice to create a new hidden service
2888 directory, key, and address for each new Single Onion Service and Hidden
2889 Service. It is not possible to run Single Onion Services and Hidden
2890 Services from the same tor instance: they should be run on different
2891 servers with different IP addresses. +
2893 HiddenServiceSingleHopMode requires HiddenServiceNonAnonymousMode to be set
2894 to 1. Since a Single Onion service is non-anonymous, you can not configure
2895 a SOCKSPort on a tor instance that is running in
2896 **HiddenServiceSingleHopMode**. Can not be changed while tor is running.
2899 [[HiddenServiceNonAnonymousMode]] **HiddenServiceNonAnonymousMode** **0**|**1**::
2900 Makes hidden services non-anonymous on this tor instance. Allows the
2901 non-anonymous HiddenServiceSingleHopMode. Enables direct connections in the
2902 server-side hidden service protocol. If you are using this option,
2903 you need to disable all client-side services on your Tor instance,
2904 including setting SOCKSPort to "0". Can not be changed while tor is
2905 running. (Default: 0)
2907 TESTING NETWORK OPTIONS
2908 -----------------------
2910 The following options are used for running a testing Tor network.
2912 [[TestingTorNetwork]] **TestingTorNetwork** **0**|**1**::
2913 If set to 1, Tor adjusts default values of the configuration options below,
2914 so that it is easier to set up a testing Tor network. May only be set if
2915 non-default set of DirAuthorities is set. Cannot be unset while Tor is
2919 ServerDNSAllowBrokenConfig 1
2920 DirAllowPrivateAddresses 1
2921 EnforceDistinctSubnets 0
2923 AuthDirMaxServersPerAddr 0
2924 AuthDirMaxServersPerAuthAddr 0
2925 ClientBootstrapConsensusAuthorityDownloadInitialDelay 0
2926 ClientBootstrapConsensusFallbackDownloadInitialDelay 0
2927 ClientBootstrapConsensusAuthorityOnlyDownloadInitialDelay 0
2928 ClientDNSRejectInternalAddresses 0
2929 ClientRejectInternalAddresses 0
2930 CountPrivateBandwidth 1
2931 ExitPolicyRejectPrivate 0
2932 ExtendAllowPrivateAddresses 1
2933 V3AuthVotingInterval 5 minutes
2934 V3AuthVoteDelay 20 seconds
2935 V3AuthDistDelay 20 seconds
2936 MinUptimeHidServDirectoryV2 0 seconds
2937 TestingV3AuthInitialVotingInterval 5 minutes
2938 TestingV3AuthInitialVoteDelay 20 seconds
2939 TestingV3AuthInitialDistDelay 20 seconds
2940 TestingAuthDirTimeToLearnReachability 0 minutes
2941 TestingEstimatedDescriptorPropagationTime 0 minutes
2942 TestingServerDownloadInitialDelay 0
2943 TestingClientDownloadInitialDelay 0
2944 TestingServerConsensusDownloadInitialDelay 0
2945 TestingClientConsensusDownloadInitialDelay 0
2946 TestingBridgeDownloadInitialDelay 10
2947 TestingBridgeBootstrapDownloadInitialDelay 0
2948 TestingClientMaxIntervalWithoutRequest 5 seconds
2949 TestingDirConnectionMaxStall 30 seconds
2950 TestingEnableConnBwEvent 1
2951 TestingEnableCellStatsEvent 1
2953 [[TestingV3AuthInitialVotingInterval]] **TestingV3AuthInitialVotingInterval** __N__ **minutes**|**hours**::
2954 Like V3AuthVotingInterval, but for initial voting interval before the first
2955 consensus has been created. Changing this requires that
2956 **TestingTorNetwork** is set. (Default: 30 minutes)
2958 [[TestingV3AuthInitialVoteDelay]] **TestingV3AuthInitialVoteDelay** __N__ **minutes**|**hours**::
2959 Like V3AuthVoteDelay, but for initial voting interval before
2960 the first consensus has been created. Changing this requires that
2961 **TestingTorNetwork** is set. (Default: 5 minutes)
2963 [[TestingV3AuthInitialDistDelay]] **TestingV3AuthInitialDistDelay** __N__ **minutes**|**hours**::
2964 Like V3AuthDistDelay, but for initial voting interval before
2965 the first consensus has been created. Changing this requires that
2966 **TestingTorNetwork** is set. (Default: 5 minutes)
2968 [[TestingV3AuthVotingStartOffset]] **TestingV3AuthVotingStartOffset** __N__ **seconds**|**minutes**|**hours**::
2969 Directory authorities offset voting start time by this much.
2970 Changing this requires that **TestingTorNetwork** is set. (Default: 0)
2972 [[TestingAuthDirTimeToLearnReachability]] **TestingAuthDirTimeToLearnReachability** __N__ **minutes**|**hours**::
2973 After starting as an authority, do not make claims about whether routers
2974 are Running until this much time has passed. Changing this requires
2975 that **TestingTorNetwork** is set. (Default: 30 minutes)
2977 [[TestingEstimatedDescriptorPropagationTime]] **TestingEstimatedDescriptorPropagationTime** __N__ **minutes**|**hours**::
2978 Clients try downloading server descriptors from directory caches after this
2979 time. Changing this requires that **TestingTorNetwork** is set. (Default:
2982 [[TestingMinFastFlagThreshold]] **TestingMinFastFlagThreshold** __N__ **bytes**|**KBytes**|**MBytes**|**GBytes**|**TBytes**|**KBits**|**MBits**|**GBits**|**TBits**::
2983 Minimum value for the Fast flag. Overrides the ordinary minimum taken
2984 from the consensus when TestingTorNetwork is set. (Default: 0.)
2986 [[TestingServerDownloadInitialDelay]] **TestingServerDownloadInitialDelay** __N__::
2987 Initial delay in seconds for when servers should download things in general. Changing this
2988 requires that **TestingTorNetwork** is set. (Default: 0)
2990 [[TestingClientDownloadInitialDelay]] **TestingClientDownloadInitialDelay** __N__::
2991 Initial delay in seconds for when clients should download things in general. Changing this
2992 requires that **TestingTorNetwork** is set. (Default: 0)
2994 [[TestingServerConsensusDownloadInitialDelay]] **TestingServerConsensusDownloadInitialDelay** __N__::
2995 Initial delay in seconds for when servers should download consensuses. Changing this
2996 requires that **TestingTorNetwork** is set. (Default: 0)
2998 [[TestingClientConsensusDownloadInitialDelay]] **TestingClientConsensusDownloadInitialDelay** __N__::
2999 Initial delay in seconds for when clients should download consensuses. Changing this
3000 requires that **TestingTorNetwork** is set. (Default: 0)
3002 [[TestingBridgeDownloadInitialDelay]] **TestingBridgeDownloadInitialDelay** __N__::
3003 Initial delay in seconds for when clients should download each bridge descriptor when they
3004 know that one or more of their configured bridges are running. Changing
3005 this requires that **TestingTorNetwork** is set. (Default: 10800)
3007 [[TestingBridgeBootstrapDownloadInitialDelay]] **TestingBridgeBootstrapDownloadInitialDelay** __N__::
3008 Initial delay in seconds for when clients should download each bridge descriptor when they
3009 have just started, or when they can not contact any of their bridges.
3010 Changing this requires that **TestingTorNetwork** is set. (Default: 0)
3012 [[TestingClientMaxIntervalWithoutRequest]] **TestingClientMaxIntervalWithoutRequest** __N__ **seconds**|**minutes**::
3013 When directory clients have only a few descriptors to request, they batch
3014 them until they have more, or until this amount of time has passed.
3015 Changing this requires that **TestingTorNetwork** is set. (Default: 10
3018 [[TestingDirConnectionMaxStall]] **TestingDirConnectionMaxStall** __N__ **seconds**|**minutes**::
3019 Let a directory connection stall this long before expiring it.
3020 Changing this requires that **TestingTorNetwork** is set. (Default:
3023 [[TestingDirAuthVoteExit]] **TestingDirAuthVoteExit** __node__,__node__,__...__::
3024 A list of identity fingerprints, country codes, and
3025 address patterns of nodes to vote Exit for regardless of their
3026 uptime, bandwidth, or exit policy. See the **ExcludeNodes**
3027 option for more information on how to specify nodes. +
3029 In order for this option to have any effect, **TestingTorNetwork**
3030 has to be set. See the **ExcludeNodes** option for more
3031 information on how to specify nodes.
3033 [[TestingDirAuthVoteExitIsStrict]] **TestingDirAuthVoteExitIsStrict** **0**|**1** ::
3034 If True (1), a node will never receive the Exit flag unless it is specified
3035 in the **TestingDirAuthVoteExit** list, regardless of its uptime, bandwidth,
3038 In order for this option to have any effect, **TestingTorNetwork**
3041 [[TestingDirAuthVoteGuard]] **TestingDirAuthVoteGuard** __node__,__node__,__...__::
3042 A list of identity fingerprints and country codes and
3043 address patterns of nodes to vote Guard for regardless of their
3044 uptime and bandwidth. See the **ExcludeNodes** option for more
3045 information on how to specify nodes. +
3047 In order for this option to have any effect, **TestingTorNetwork**
3050 [[TestingDirAuthVoteGuardIsStrict]] **TestingDirAuthVoteGuardIsStrict** **0**|**1** ::
3051 If True (1), a node will never receive the Guard flag unless it is specified
3052 in the **TestingDirAuthVoteGuard** list, regardless of its uptime and bandwidth. +
3054 In order for this option to have any effect, **TestingTorNetwork**
3057 [[TestingDirAuthVoteHSDir]] **TestingDirAuthVoteHSDir** __node__,__node__,__...__::
3058 A list of identity fingerprints and country codes and
3059 address patterns of nodes to vote HSDir for regardless of their
3060 uptime and DirPort. See the **ExcludeNodes** option for more
3061 information on how to specify nodes. +
3063 In order for this option to have any effect, **TestingTorNetwork**
3066 [[TestingDirAuthVoteHSDirIsStrict]] **TestingDirAuthVoteHSDirIsStrict** **0**|**1** ::
3067 If True (1), a node will never receive the HSDir flag unless it is specified
3068 in the **TestingDirAuthVoteHSDir** list, regardless of its uptime and DirPort. +
3070 In order for this option to have any effect, **TestingTorNetwork**
3073 [[TestingEnableConnBwEvent]] **TestingEnableConnBwEvent** **0**|**1**::
3074 If this option is set, then Tor controllers may register for CONN_BW
3075 events. Changing this requires that **TestingTorNetwork** is set.
3078 [[TestingEnableCellStatsEvent]] **TestingEnableCellStatsEvent** **0**|**1**::
3079 If this option is set, then Tor controllers may register for CELL_STATS
3080 events. Changing this requires that **TestingTorNetwork** is set.
3083 [[TestingMinExitFlagThreshold]] **TestingMinExitFlagThreshold** __N__ **KBytes**|**MBytes**|**GBytes**|**TBytes**|**KBits**|**MBits**|**GBits**|**TBits**::
3084 Sets a lower-bound for assigning an exit flag when running as an
3085 authority on a testing network. Overrides the usual default lower bound
3086 of 4 KB. (Default: 0)
3088 [[TestingLinkCertLifetime]] **TestingLinkCertLifetime** __N__ **seconds**|**minutes**|**hours**|**days**|**weeks**|**months**::
3089 Overrides the default lifetime for the certificates used to authenticate
3090 our X509 link cert with our ed25519 signing key.
3093 [[TestingAuthKeyLifetime]] **TestingAuthKeyLifetime** __N__ **seconds**|**minutes**|**hours**|**days**|**weeks**|**months**::
3094 Overrides the default lifetime for a signing Ed25519 TLS Link authentication
3098 [[TestingLinkKeySlop]] **TestingLinkKeySlop** __N__ **seconds**|**minutes**|**hours** +
3100 [[TestingAuthKeySlop]] **TestingAuthKeySlop** __N__ **seconds**|**minutes**|**hours** +
3102 [[TestingSigningKeySlop]] **TestingSigningKeySlop** __N__ **seconds**|**minutes**|**hours**::
3103 How early before the official expiration of a an Ed25519 signing key do
3104 we replace it and issue a new key?
3105 (Default: 3 hours for link and auth; 1 day for signing.)
3107 NON-PERSISTENT OPTIONS
3108 ----------------------
3110 These options are not saved to the torrc file by the "SAVECONF" controller
3111 command. Other options of this type are documented in control-spec.txt,
3112 section 5.4. End-users should mostly ignore them.
3114 [[UnderscorePorts]] **\_\_ControlPort**, **\_\_DirPort**, **\_\_DNSPort**, **\_\_ExtORPort**, **\_\_NATDPort**, **\_\_ORPort**, **\_\_SocksPort**, **\_\_TransPort**::
3115 These underscore-prefixed options are variants of the regular Port
3116 options. They behave the same, except they are not saved to the
3117 torrc file by the controller's SAVECONF command.
3123 Tor catches the following signals:
3125 [[SIGTERM]] **SIGTERM**::
3126 Tor will catch this, clean up and sync to disk if necessary, and exit.
3128 [[SIGINT]] **SIGINT**::
3129 Tor clients behave as with SIGTERM; but Tor servers will do a controlled
3130 slow shutdown, closing listeners and waiting 30 seconds before exiting.
3131 (The delay can be configured with the ShutdownWaitLength config option.)
3133 [[SIGHUP]] **SIGHUP**::
3134 The signal instructs Tor to reload its configuration (including closing and
3135 reopening logs), and kill and restart its helper processes if applicable.
3137 [[SIGUSR1]] **SIGUSR1**::
3138 Log statistics about current connections, past connections, and throughput.
3140 [[SIGUSR2]] **SIGUSR2**::
3141 Switch all logs to loglevel debug. You can go back to the old loglevels by
3144 [[SIGCHLD]] **SIGCHLD**::
3145 Tor receives this signal when one of its helper processes has exited, so it
3148 [[SIGPIPE]] **SIGPIPE**::
3149 Tor catches this signal and ignores it.
3151 [[SIGXFSZ]] **SIGXFSZ**::
3152 If this signal exists on your platform, Tor catches and ignores it.
3157 **@CONFDIR@/torrc**::
3158 The configuration file, which contains "option value" pairs.
3161 Fallback location for torrc, if @CONFDIR@/torrc is not found.
3163 **@LOCALSTATEDIR@/lib/tor/**::
3164 The tor process stores keys and other data here.
3167 __CacheDirectory__**/cached-certs**::
3168 This file holds downloaded directory key certificates that are used to
3169 verify authenticity of documents generated by Tor directory authorities.
3171 __CacheDirectory__**/cached-consensus** and/or **cached-microdesc-consensus**::
3172 The most recent consensus network status document we've downloaded.
3174 __CacheDirectory__**/cached-descriptors** and **cached-descriptors.new**::
3175 These files hold downloaded router statuses. Some routers may appear more
3176 than once; if so, the most recently published descriptor is used. Lines
3177 beginning with @-signs are annotations that contain more information about
3178 a given router. The ".new" file is an append-only journal; when it gets
3179 too large, all entries are merged into a new cached-descriptors file.
3181 __CacheDirectory__**/cached-extrainfo** and **cached-extrainfo.new**::
3182 As "cached-descriptors", but holds optionally-downloaded "extra-info"
3183 documents. Relays use these documents to send inessential information
3184 about statistics, bandwidth history, and network health to the
3185 authorities. They aren't fetched by default; see the DownloadExtraInfo
3186 option for more info.
3188 __CacheDirectory__**/cached-microdescs** and **cached-microdescs.new**::
3189 These files hold downloaded microdescriptors. Lines beginning with
3190 @-signs are annotations that contain more information about a given
3191 router. The ".new" file is an append-only journal; when it gets too
3192 large, all entries are merged into a new cached-microdescs file.
3194 __CacheDirectory__**/cached-routers** and **cached-routers.new**::
3195 Obsolete versions of cached-descriptors and cached-descriptors.new. When
3196 Tor can't find the newer files, it looks here instead.
3198 __DataDirectory__**/state**::
3199 A set of persistent key-value mappings. These are documented in
3200 the file. These include:
3201 - The current entry guards and their status.
3202 - The current bandwidth accounting values.
3203 - When the file was last written
3204 - What version of Tor generated the state file
3205 - A short history of bandwidth usage, as produced in the server
3208 __DataDirectory__**/sr-state**::
3209 Authority only. State file used to record information about the current
3210 status of the shared-random-value voting state.
3212 __CacheDirectory__**/diff-cache**::
3213 Directory cache only. Holds older consensuses, and diffs from older
3214 consensuses to the most recent consensus of each type, compressed
3215 in various ways. Each file contains a set of key-value arguments
3216 describing its contents, followed by a single NUL byte, followed by the
3219 __DataDirectory__**/bw_accounting**::
3220 Used to track bandwidth accounting values (when the current period starts
3221 and ends; how much has been read and written so far this period). This file
3222 is obsolete, and the data is now stored in the \'state' file instead.
3224 __DataDirectory__**/control_auth_cookie**::
3225 Used for cookie authentication with the controller. Location can be
3226 overridden by the CookieAuthFile config option. Regenerated on startup. See
3227 control-spec.txt in https://spec.torproject.org/[torspec] for details.
3228 Only used when cookie authentication is enabled.
3230 __DataDirectory__**/lock**::
3231 This file is used to prevent two Tor instances from using same data
3232 directory. If access to this file is locked, data directory is already
3235 __DataDirectory__**/key-pinning-journal**::
3236 Used by authorities. A line-based file that records mappings between
3237 RSA1024 identity keys and Ed25519 identity keys. Authorities enforce
3238 these mappings, so that once a relay has picked an Ed25519 key, stealing
3239 or factoring the RSA1024 key will no longer let an attacker impersonate
3242 __KeyDirectory__**/authority_identity_key**::
3243 A v3 directory authority's master identity key, used to authenticate its
3244 signing key. Tor doesn't use this while it's running. The tor-gencert
3245 program uses this. If you're running an authority, you should keep this
3246 key offline, and not actually put it here.
3248 __KeyDirectory__**/authority_certificate**::
3249 A v3 directory authority's certificate, which authenticates the authority's
3250 current vote- and consensus-signing key using its master identity key.
3251 Only directory authorities use this file.
3253 __KeyDirectory__**/authority_signing_key**::
3254 A v3 directory authority's signing key, used to sign votes and consensuses.
3255 Only directory authorities use this file. Corresponds to the
3256 **authority_certificate** cert.
3258 __KeyDirectory__**/legacy_certificate**::
3259 As authority_certificate: used only when V3AuthUseLegacyKey is set.
3260 See documentation for V3AuthUseLegacyKey.
3262 __KeyDirectory__**/legacy_signing_key**::
3263 As authority_signing_key: used only when V3AuthUseLegacyKey is set.
3264 See documentation for V3AuthUseLegacyKey.
3266 __KeyDirectory__**/secret_id_key**::
3267 A relay's RSA1024 permanent identity key, including private and public
3268 components. Used to sign router descriptors, and to sign other keys.
3270 __KeyDirectory__**/ed25519_master_id_public_key**::
3271 The public part of a relay's Ed25519 permanent identity key.
3273 __KeyDirectory__**/ed25519_master_id_secret_key**::
3274 The private part of a relay's Ed25519 permanent identity key. This key
3275 is used to sign the medium-term ed25519 signing key. This file can be
3276 kept offline, or kept encrypted. If so, Tor will not be able to generate
3277 new signing keys itself; you'll need to use tor --keygen yourself to do
3280 __KeyDirectory__**/ed25519_signing_secret_key**::
3281 The private and public components of a relay's medium-term Ed25519 signing
3282 key. This key is authenticated by the Ed25519 master key, in turn
3283 authenticates other keys (and router descriptors).
3285 __KeyDirectory__**/ed25519_signing_cert**::
3286 The certificate which authenticates "ed25519_signing_secret_key" as
3287 having been signed by the Ed25519 master key.
3289 __KeyDirectory__**/secret_onion_key** and **secret_onion_key.old**::
3290 A relay's RSA1024 short-term onion key. Used to decrypt old-style ("TAP")
3291 circuit extension requests. The ".old" file holds the previously
3292 generated key, which the relay uses to handle any requests that were
3293 made by clients that didn't have the new one.
3295 __KeyDirectory__**/secret_onion_key_ntor** and **secret_onion_key_ntor.old**::
3296 A relay's Curve25519 short-term onion key. Used to handle modern ("ntor")
3297 circuit extension requests. The ".old" file holds the previously
3298 generated key, which the relay uses to handle any requests that were
3299 made by clients that didn't have the new one.
3301 __DataDirectory__**/fingerprint**::
3302 Only used by servers. Holds the fingerprint of the server's identity key.
3304 __DataDirectory__**/hashed-fingerprint**::
3305 Only used by bridges. Holds the hashed fingerprint of the bridge's
3306 identity key. (That is, the hash of the hash of the identity key.)
3308 __DataDirectory__**/approved-routers**::
3309 Only used by authoritative directory servers. This file lists
3310 the status of routers by their identity fingerprint.
3311 Each line lists a status and a fingerprint separated by
3312 whitespace. See your **fingerprint** file in the __DataDirectory__ for an
3313 example line. If the status is **!reject** then descriptors from the
3314 given identity (fingerprint) are rejected by this server. If it is
3315 **!invalid** then descriptors are accepted but marked in the directory as
3316 not valid, that is, not recommended.
3318 __DataDirectory__**/v3-status-votes**::
3319 Only for v3 authoritative directory servers. This file contains
3320 status votes from all the authoritative directory servers.
3322 __CacheDirectory__**/unverified-consensus**::
3323 This file contains a network consensus document that has been downloaded,
3324 but which we didn't have the right certificates to check yet.
3326 __CacheDirectory__**/unverified-microdesc-consensus**::
3327 This file contains a microdescriptor-flavored network consensus document
3328 that has been downloaded, but which we didn't have the right certificates
3331 __DataDirectory__**/unparseable-desc**::
3332 Onion server descriptors that Tor was unable to parse are dumped to this
3333 file. Only used for debugging.
3335 __DataDirectory__**/router-stability**::
3336 Only used by authoritative directory servers. Tracks measurements for
3337 router mean-time-between-failures so that authorities have a good idea of
3338 how to set their Stable flags.
3340 __DataDirectory__**/stats/dirreq-stats**::
3341 Only used by directory caches and authorities. This file is used to
3342 collect directory request statistics.
3344 __DataDirectory__**/stats/entry-stats**::
3345 Only used by servers. This file is used to collect incoming connection
3346 statistics by Tor entry nodes.
3348 __DataDirectory__**/stats/bridge-stats**::
3349 Only used by servers. This file is used to collect incoming connection
3350 statistics by Tor bridges.
3352 __DataDirectory__**/stats/exit-stats**::
3353 Only used by servers. This file is used to collect outgoing connection
3354 statistics by Tor exit routers.
3356 __DataDirectory__**/stats/buffer-stats**::
3357 Only used by servers. This file is used to collect buffer usage
3360 __DataDirectory__**/stats/conn-stats**::
3361 Only used by servers. This file is used to collect approximate connection
3362 history (number of active connections over time).
3364 __DataDirectory__**/stats/hidserv-stats**::
3365 Only used by servers. This file is used to collect approximate counts
3366 of what fraction of the traffic is hidden service rendezvous traffic, and
3367 approximately how many hidden services the relay has seen.
3369 __DataDirectory__**/networkstatus-bridges**::
3370 Only used by authoritative bridge directories. Contains information
3371 about bridges that have self-reported themselves to the bridge
3374 __DataDirectory__**/approved-routers**::
3375 Authorities only. This file is used to configure which relays are
3376 known to be valid, invalid, and so forth.
3378 __HiddenServiceDirectory__**/hostname**::
3379 The <base32-encoded-fingerprint>.onion domain name for this hidden service.
3380 If the hidden service is restricted to authorized clients only, this file
3381 also contains authorization data for all clients.
3383 Note that clients will ignore any extra subdomains prepended to a hidden
3384 service hostname. So if you have "xyz.onion" as your hostname, you
3385 can tell clients to connect to "www.xyz.onion" or "irc.xyz.onion"
3386 for virtual-hosting purposes.
3388 __HiddenServiceDirectory__**/private_key**::
3389 The private key for this hidden service.
3391 __HiddenServiceDirectory__**/client_keys**::
3392 Authorization data for a hidden service that is only accessible by
3395 __HiddenServiceDirectory__**/onion_service_non_anonymous**::
3396 This file is present if a hidden service key was created in
3397 **HiddenServiceNonAnonymousMode**.
3401 **torsocks**(1), **torify**(1) +
3403 **https://www.torproject.org/**
3405 **torspec: https://spec.torproject.org **
3410 Plenty, probably. Tor is still in development. Please report them at https://trac.torproject.org/.
3414 Roger Dingledine [arma at mit.edu], Nick Mathewson [nickm at alum.mit.edu].