other versions
- wheezy 0.2.4.27-1
- jessie 0.2.5.12-4
- jessie-backports 0.2.9.9-1~bpo8+1
- testing 0.2.9.10-1
- unstable 0.2.9.10-1
- experimental 0.3.0.7-1
TOR(1) | Tor Manual | TOR(1) |
NAME¶
tor - The second-generation onion routerSYNOPSIS¶
tor [OPTION value]...DESCRIPTION¶
tor is a connection-oriented anonymizing communication service. Users choose a source-routed path through a set of nodes, and negotiate a "virtual circuit" through the network, in which each node knows its predecessor and successor, but no others. Traffic flowing down the circuit is unwrapped by a symmetric key at each node, which reveals the downstream node.COMMAND-LINE OPTIONS¶
-h, -helpDisplay a short help message and exit.
-f FILE
Specify a new configuration file to contain
further Tor configuration options. (Default: /etc/tor/torrc, or $HOME/.torrc
if that file is not found)
--defaults-torrc FILE
Specify a file in which to find default values
for Tor options. The contents of this file are overridden by those in the
regular configuration file, and by those on the command line. (Default:
/etc/tor/torrc-defaults.)
--hash-password
Generates a hashed password for control port
access.
--list-fingerprint
Generate your keys and output your nickname
and fingerprint.
--verify-config
Verify the configuration file is valid.
--service install [--options command-line options]
Install an instance of Tor as a Windows
service, with the provided command-line options. Current instructions can be
found at
https://trac.torproject.org/projects/tor/wiki/doc/TorFAQ#HowdoIrunmyTorrelayasanNTservice
--service remove|start|stop
Remove, start, or stop a configured Tor
Windows service.
--nt-service
Used internally to implement a Windows
service.
--list-torrc-options
List all valid options.
--version
Display Tor version and exit.
--quiet|--hush
Override the default console log. By default,
Tor starts out logging messages at level "notice" and higher to the
console. It stops doing so after it parses its configuration, if the
configuration tells it to log anywhere else. You can override this behavior
with the --hush option, which tells Tor to only send warnings and
errors to the console, or with the --quiet option, which tells Tor not
to log to the console at all.
THE CONFIGURATION FILE FORMAT¶
All configuration options in a configuration are written on a single line by default. They take the form of an option name and a value, or an option name and a quoted value (option value or option "value"). Anything after a # character is treated as a comment. Options are case-insensitive. C-style escaped characters are allowed inside quoted values. To split one configuration entry into multiple lines, use a single backslash character (\) before the end of the line. Comments can be used in such multiline entries, but they must start at the beginning of a line.GENERAL OPTIONS¶
BandwidthRate N bytes|KBytes|MBytes|GBytesA token bucket limits the average incoming
bandwidth usage on this node to the specified number of bytes per second, and
the average outgoing bandwidth usage to that same value. If you want to run a
relay in the public network, this needs to be at the very least 30
KBytes (that is, 30720 bytes). (Default: 1 GByte)
BandwidthBurst N
bytes|KBytes|MBytes|GBytes
Limit the maximum token bucket size (also
known as the burst) to the given number of bytes in each direction. (Default:
1 GByte)
MaxAdvertisedBandwidth N
bytes|KBytes|MBytes|GBytes
If set, we will not advertise more than this
amount of bandwidth for our BandwidthRate. Server operators who want to reduce
the number of clients who ask to build circuits through them (since this is
proportional to advertised bandwidth rate) can thus reduce the CPU demands on
their server without impacting network performance.
RelayBandwidthRate N
bytes|KBytes|MBytes|GBytes
If not 0, a separate token bucket limits the
average incoming bandwidth usage for _relayed traffic_ on this node to the
specified number of bytes per second, and the average outgoing bandwidth usage
to that same value. Relayed traffic currently is calculated to include answers
to directory requests, but that may change in future versions. (Default:
0)
RelayBandwidthBurst N
bytes|KBytes|MBytes|GBytes
If not 0, limit the maximum token bucket size
(also known as the burst) for _relayed traffic_ to the given number of bytes
in each direction. (Default: 0)
PerConnBWRate N
bytes|KBytes|MBytes|GBytes
If set, do separate rate limiting for each
connection from a non-relay. You should never need to change this value, since
a network-wide value is published in the consensus and your relay will use
that value. (Default: 0)
PerConnBWBurst N
bytes|KBytes|MBytes|GBytes
If set, do separate rate limiting for each
connection from a non-relay. You should never need to change this value, since
a network-wide value is published in the consensus and your relay will use
that value. (Default: 0)
ClientTransportPlugin transport socks4|socks5
IP:PORT, ClientTransportPlugin transport exec
path-to-binary [options]
In its first form, when set along with a
corresponding Bridge line, the Tor client forwards its traffic to a
SOCKS-speaking proxy on "IP:PORT". It’s the duty of that proxy
to properly forward the traffic to the bridge.
In its second form, when set along with a corresponding Bridge line, the Tor
client launches the pluggable transport proxy executable in
path-to-binary using options as its command-line options, and
forwards its traffic to it. It’s the duty of that proxy to properly
forward the traffic to the bridge.
ServerTransportPlugin transport exec path-to-binary
[options]
The Tor relay launches the pluggable transport
proxy in path-to-binary using options as its command-line
options, and expects to receive proxied client traffic from it.
ServerTransportListenAddr transport IP:PORT
When this option is set, Tor will suggest
IP: PORT as the listening address of any pluggable transport
proxy that tries to launch transport.
ConnLimit NUM
The minimum number of file descriptors that
must be available to the Tor process before it will start. Tor will ask the OS
for as many file descriptors as the OS will allow (you can find this by
"ulimit -H -n"). If this number is less than ConnLimit, then Tor
will refuse to start.
You probably don’t need to adjust this. It has no effect on Windows since
that platform lacks getrlimit(). (Default: 1000)
DisableNetwork 0|1
When this option is set, we don’t listen
for or accept any connections other than controller connections, and we
don’t make any outbound connections. Controllers sometimes use this
option to avoid using the network until Tor is fully configured. (Default:
0)
ConstrainedSockets 0|1
If set, Tor will tell the kernel to attempt to
shrink the buffers for all sockets to the size specified in
ConstrainedSockSize. This is useful for virtual servers and other
environments where system level TCP buffers may be limited. If you’re on
a virtual server, and you encounter the "Error creating network socket:
No buffer space available" message, you are likely experiencing this
problem.
The preferred solution is to have the admin increase the buffer pool for the
host itself via /proc/sys/net/ipv4/tcp_mem or equivalent facility; this
configuration option is a second-resort.
The DirPort option should also not be used if TCP buffers are scarce. The cached
directory requests consume additional sockets which exacerbates the problem.
You should not enable this feature unless you encounter the "no
buffer space available" issue. Reducing the TCP buffers affects window
size for the TCP stream and will reduce throughput in proportion to round trip
time on long paths. (Default: 0)
ConstrainedSockSize N bytes|KBytes
When ConstrainedSockets is enabled the
receive and transmit buffers for all sockets will be set to this limit. Must
be a value between 2048 and 262144, in 1024 byte increments. Default of 8192
is recommended.
ControlPort PORT|auto
If set, Tor will accept connections on this
port and allow those connections to control the Tor process using the Tor
Control Protocol (described in control-spec.txt). Note: unless you also
specify one or more of HashedControlPassword or
CookieAuthentication, setting this option will cause Tor to allow any
process on the local host to control it. (Setting both authentication methods
means either method is sufficient to authenticate to Tor.) This option is
required for many Tor controllers; most use the value of 9051. Set it to
"auto" to have Tor pick a port for you. (Default: 0)
ControlListenAddress IP[:PORT]
Bind the controller listener to this address.
If you specify a port, bind to this port rather than the one specified in
ControlPort. We strongly recommend that you leave this alone unless you know
what you’re doing, since giving attackers access to your control
listener is really dangerous. This directive can be specified multiple times
to bind to multiple addresses/ports. (Default: 127.0.0.1)
ControlSocket Path
Like ControlPort, but listens on a Unix domain
socket, rather than a TCP socket. (Unix and Unix-like systems only.)
ControlSocketsGroupWritable 0|1
If this option is set to 0, don’t allow
the filesystem group to read and write unix sockets (e.g. ControlSocket). If
the option is set to 1, make the control socket readable and writable by the
default GID. (Default: 0)
HashedControlPassword hashed_password
Allow connections on the control port if they
present the password whose one-way hash is hashed_password. You can
compute the hash of a password by running "tor --hash-password
password". You can provide several acceptable passwords by using
more than one HashedControlPassword line.
CookieAuthentication 0|1
If this option is set to 1, allow connections
on the control port when the connecting process knows the contents of a file
named "control_auth_cookie", which Tor will create in its data
directory. This authentication method should only be used on systems with good
filesystem security. (Default: 0)
CookieAuthFile Path
If set, this option overrides the default
location and file name for Tor’s cookie file. (See CookieAuthentication
above.)
CookieAuthFileGroupReadable 0|1|Groupname
If this option is set to 0, don’t allow
the filesystem group to read the cookie file. If the option is set to 1, make
the cookie file readable by the default GID. [Making the file readable by
other groups is not yet implemented; let us know if you need this for some
reason.] (Default: 0)
ControlPortWriteToFile Path
If set, Tor writes the address and port of any
control port it opens to this address. Usable by controllers to learn the
actual control port when ControlPort is set to "auto".
ControlPortFileGroupReadable 0|1
If this option is set to 0, don’t allow
the filesystem group to read the control port file. If the option is set to 1,
make the control port file readable by the default GID. (Default: 0)
DataDirectory DIR
Store working data in DIR (Default:
/var/lib/tor)
FallbackDir address:port orport=port
id=fingerprint [weight= num]
When we’re unable to connect to any
directory cache for directory info (usually because we don’t know about
any yet) we try a FallbackDir. By default, the directory authorities are also
FallbackDirs.
DirAuthority [nickname] [flags] address:port
fingerprint
Use a nonstandard authoritative directory
server at the provided address and port, with the specified key fingerprint.
This option can be repeated many times, for multiple authoritative directory
servers. Flags are separated by spaces, and determine what kind of an
authority this directory is. By default, every authority is authoritative for
current ("v2")-style directories, unless the "no-v2" flag
is given. If the "v1" flags is provided, Tor will use this server as
an authority for old-style (v1) directories as well. (Only directory mirrors
care about this.) Tor will use this server as an authority for hidden service
information if the "hs" flag is set, or if the "v1" flag
is set and the "no-hs" flag is not set. Tor will use this
authority as a bridge authoritative directory if the "bridge" flag
is set. If a flag "orport= port" is given, Tor will use the
given port when opening encrypted tunnels to the dirserver. If a flag
"weight= num" is given, then the directory server is chosen
randomly with probability proportional to that weight (default 1.0). Lastly,
if a flag "v3ident= fp" is given, the dirserver is a v3
directory authority whose v3 long-term signing key has the fingerprint
fp.
If no DirAuthority line is given, Tor will use the default directory
authorities. NOTE: this option is intended for setting up a private Tor
network with its own directory authorities. If you use it, you will be
distinguishable from other users, because you won’t believe the same
authorities they do.
DirAuthorityFallbackRate NUM
When configured to use both directory
authorities and fallback directories, the directory authorities also work as
fallbacks. They are chosen with their regular weights, multiplied by this
number, which should be 1.0 or less. (Default: 1.0)
DynamicDHGroups 0|1
If this option is set to 1, when running as a
server, generate our own Diffie-Hellman group instead of using the one from
Apache’s mod_ssl. This option may help circumvent censorship based on
static Diffie-Hellman parameters. (Default: 0)
These options behave as DirAuthority, but they
replace fewer of the default directory authorities. Using
AlternateDirAuthority replaces the default Tor directory authorities, but
leaves the default hidden service authorities and bridge authorities in place.
Similarly, AlternateHSAuthority replaces the default hidden service
authorities, but not the directory or bridge authorities; and
AlternateBridgeAuthority replaces the default bridge authority, but leaves the
directory and hidden service authorities alone.
DisableAllSwap 0|1
If set to 1, Tor will attempt to lock all
current and future memory pages, so that memory cannot be paged out. Windows,
OS X and Solaris are currently not supported. We believe that this feature
works on modern Gnu/Linux distributions, and that it should work on *BSD
systems (untested). This option requires that you start your Tor as root, and
you should use the User option to properly reduce Tor’s
privileges. (Default: 0)
DisableDebuggerAttachment 0|1
If set to 1, Tor will attempt to prevent basic
debugging attachment attempts by other processes. This may also keep Tor from
generating core files if it crashes. It has no impact for users who wish to
attach if they have CAP_SYS_PTRACE or if they are root. We believe that this
feature works on modern Gnu/Linux distributions, and that it may also work on
*BSD systems (untested). Some modern Gnu/Linux systems such as Ubuntu have the
kernel.yama.ptrace_scope sysctl and by default enable it as an attempt to
limit the PTRACE scope for all user processes by default. This feature will
attempt to limit the PTRACE scope for Tor specifically - it will not attempt
to alter the system wide ptrace scope as it may not even exist. If you wish to
attach to Tor with a debugger such as gdb or strace you will want to set this
to 0 for the duration of your debugging. Normal users should leave it on.
Disabling this option while Tor is running is prohibited. (Default: 1)
FetchDirInfoEarly 0|1
If set to 1, Tor will always fetch directory
information like other directory caches, even if you don’t meet the
normal criteria for fetching early. Normal users should leave it off.
(Default: 0)
FetchDirInfoExtraEarly 0|1
If set to 1, Tor will fetch directory
information before other directory caches. It will attempt to download
directory information closer to the start of the consensus period. Normal
users should leave it off. (Default: 0)
FetchHidServDescriptors 0|1
If set to 0, Tor will never fetch any hidden
service descriptors from the rendezvous directories. This option is only
useful if you’re using a Tor controller that handles hidden service
fetches for you. (Default: 1)
FetchServerDescriptors 0|1
If set to 0, Tor will never fetch any network
status summaries or server descriptors from the directory servers. This option
is only useful if you’re using a Tor controller that handles directory
fetches for you. (Default: 1)
FetchUselessDescriptors 0|1
If set to 1, Tor will fetch every non-obsolete
descriptor from the authorities that it hears about. Otherwise, it will avoid
fetching useless descriptors, for example for routers that are not running.
This option is useful if you’re using the contributed
"exitlist" script to enumerate Tor nodes that exit to certain
addresses. (Default: 0)
HTTPProxy host[:port]
Tor will make all its directory requests
through this host:port (or host:80 if port is not specified), rather than
connecting directly to any directory servers.
HTTPProxyAuthenticator username:password
If defined, Tor will use this
username:password for Basic HTTP proxy authentication, as in RFC 2617. This is
currently the only form of HTTP proxy authentication that Tor supports; feel
free to submit a patch if you want it to support others.
HTTPSProxy host[:port]
Tor will make all its OR (SSL) connections
through this host:port (or host:443 if port is not specified), via HTTP
CONNECT rather than connecting directly to servers. You may want to set
FascistFirewall to restrict the set of ports you might try to connect
to, if your HTTPS proxy only allows connecting to certain ports.
HTTPSProxyAuthenticator username:password
If defined, Tor will use this
username:password for Basic HTTPS proxy authentication, as in RFC 2617. This
is currently the only form of HTTPS proxy authentication that Tor supports;
feel free to submit a patch if you want it to support others.
Socks4Proxy host[:port]
Tor will make all OR connections through the
SOCKS 4 proxy at host:port (or host:1080 if port is not specified).
Socks5Proxy host[:port]
Tor will make all OR connections through the
SOCKS 5 proxy at host:port (or host:1080 if port is not specified).
If defined, authenticate to the SOCKS 5 server
using username and password in accordance to RFC 1929. Both username and
password must be between 1 and 255 characters.
KeepalivePeriod NUM
To keep firewalls from expiring connections,
send a padding keepalive cell every NUM seconds on open connections that are
in use. If the connection has no open circuits, it will instead be closed
after NUM seconds of idleness. (Default: 5 minutes)
Log minSeverity[-maxSeverity]
stderr|stdout|syslog
Send all messages between minSeverity
and maxSeverity to the standard output stream, the standard error
stream, or to the system log. (The "syslog" value is only supported
on Unix.) Recognized severity levels are debug, info, notice, warn, and err.
We advise using "notice" in most cases, since anything more verbose
may provide sensitive information to an attacker who obtains the logs. If only
one severity level is given, all messages of that level or higher will be sent
to the listed destination.
Log minSeverity[-maxSeverity] file FILENAME
As above, but send log messages to the listed
filename. The "Log" option may appear more than once in a
configuration file. Messages are sent to all the logs that match their
severity level.
As above, but select messages by range of log
severity and by a set of "logging domains". Each logging
domain corresponds to an area of functionality inside Tor. You can specify any
number of severity ranges for a single log statement, each of them prefixed by
a comma-separated list of logging domains. You can prefix a domain with ~ to
indicate negation, and use * to indicate "all domains". If you
specify a severity range without a list of domains, it matches all domains.
This is an advanced feature which is most useful for debugging one or two of
Tor’s subsystems at a time.
The currently recognized domains are: general, crypto, net, config, fs,
protocol, mm, http, app, control, circ, rend, bug, dir, dirserv, or, edge,
acct, hist, and handshake. Domain names are case-insensitive.
For example, "Log [handshake]debug [~net,~mm]info notice stdout" sends
to stdout: all handshake messages of any severity, all info-and-higher
messages from domains other than networking and memory management, and all
messages of severity notice or higher.
LogMessageDomains 0|1
If 1, Tor includes message domains with each
log message. Every log message currently has at least one domain; most
currently have exactly one. This doesn’t affect controller log messages.
(Default: 0)
OutboundBindAddress IP
Make all outbound connections originate from
the IP address specified. This is only useful when you have multiple network
interfaces, and you want all of Tor’s outgoing connections to use a
single one. This option may be used twice, once with an IPv4 address and once
with an IPv6 address. This setting will be ignored for connections to the
loopback addresses (127.0.0.0/8 and ::1).
PidFile FILE
On startup, write our PID to FILE. On clean
shutdown, remove FILE.
ProtocolWarnings 0|1
If 1, Tor will log with severity 'warn'
various cases of other parties not following the Tor specification. Otherwise,
they are logged with severity 'info'. (Default: 0)
RunAsDaemon 0|1
If 1, Tor forks and daemonizes to the
background. This option has no effect on Windows; instead you should use the
--service command-line option. (Default: 0)
LogTimeGranularity NUM
Set the resolution of timestamps in
Tor’s logs to NUM milliseconds. NUM must be positive and either a
divisor or a multiple of 1 second. Note that this option only controls the
granularity written by Tor to a file or console log. Tor does not (for
example) "batch up" log messages to affect times logged by a
controller, times attached to syslog messages, or the mtime fields on log
files. (Default: 1 second)
SafeLogging 0|1|relay
Tor can scrub potentially sensitive strings
from log messages (e.g. addresses) by replacing them with the string
[scrubbed]. This way logs can still be useful, but they don’t leave
behind personally identifying information about what sites a user might have
visited.
If this option is set to 0, Tor will not perform any scrubbing, if it is set to
1, all potentially sensitive strings are replaced. If it is set to relay, all
log messages generated when acting as a relay are sanitized, but all messages
generated when acting as a client are not. (Default: 1)
User UID
On startup, setuid to this user and setgid to
their primary group.
HardwareAccel 0|1
If non-zero, try to use built-in (static)
crypto hardware acceleration when available. (Default: 0)
AccelName NAME
When using OpenSSL hardware crypto
acceleration attempt to load the dynamic engine of this name. This must be
used for any dynamic hardware engine. Names can be verified with the openssl
engine command.
AccelDir DIR
Specify this option if using dynamic hardware
acceleration and the engine implementation library resides somewhere other
than the OpenSSL default.
AvoidDiskWrites 0|1
If non-zero, try to write to disk less
frequently than we would otherwise. This is useful when running on flash
memory or other media that support only a limited number of writes. (Default:
0)
TunnelDirConns 0|1
If non-zero, when a directory server we
contact supports it, we will build a one-hop circuit and make an encrypted
connection via its ORPort. (Default: 1)
PreferTunneledDirConns 0|1
If non-zero, we will avoid directory servers
that don’t support tunneled directory connections, when possible.
(Default: 1)
CircuitPriorityHalflife NUM1
If this value is set, we override the default
algorithm for choosing which circuit’s cell to deliver or relay next.
When the value is 0, we round-robin between the active circuits on a
connection, delivering one cell from each in turn. When the value is positive,
we prefer delivering cells from whichever connection has the lowest weighted
cell count, where cells are weighted exponentially according to the supplied
CircuitPriorityHalflife value (in seconds). If this option is not set at all,
we use the behavior recommended in the current consensus networkstatus. This
is an advanced option; you generally shouldn’t have to mess with it.
(Default: not set)
DisableIOCP 0|1
If Tor was built to use the Libevent’s
"bufferevents" networking code and you’re running on Windows,
setting this option to 1 will tell Libevent not to use the Windows IOCP
networking API. (Default: 1)
UserspaceIOCPBuffers 0|1
If IOCP is enabled (see DisableIOCP above),
setting this option to 1 will tell Tor to disable kernel-space TCP buffers, in
order to avoid needless copy operations and try not to run out of non-paged
RAM. This feature is experimental; don’t use it yet unless you’re
eager to help tracking down bugs. (Default: 0)
_UseFilteringSSLBufferevents 0|1
Tells Tor to do its SSL communication using a
chain of bufferevents: one for SSL and one for networking. This option has no
effect if bufferevents are disabled (in which case it can’t turn on), or
if IOCP bufferevents are enabled (in which case it can’t turn off). This
option is useful for debugging only; most users shouldn’t touch it.
(Default: 0)
CountPrivateBandwidth 0|1
If this option is set, then Tor’s
rate-limiting applies not only to remote connections, but also to connections
to private addresses like 127.0.0.1 or 10.0.0.1. This is mostly useful for
debugging rate-limiting. (Default: 0)
CLIENT OPTIONS¶
The following options are useful only for clients (that is, if SocksPort, TransPort, DNSPort, or NATDPort is non-zero): AllowInvalidNodes entry|exit|middle|introduction| rendezvous|...If some Tor servers are obviously not working
right, the directory authorities can manually mark them as invalid, meaning
that it’s not recommended you use them for entry or exit positions in
your circuits. You can opt to use them in some circuit positions, though. The
default is "middle,rendezvous", and other choices are not
advised.
ExcludeSingleHopRelays 0|1
This option controls whether circuits built by
Tor will include relays with the AllowSingleHopExits flag set to true. If
ExcludeSingleHopRelays is set to 0, these relays will be included. Note that
these relays might be at higher risk of being seized or observed, so they are
not normally included. Also note that relatively few clients turn off this
option, so using these relays might make your client stand out. (Default:
1)
Bridge [transport] IP:ORPort [fingerprint]
When set along with UseBridges, instructs Tor
to use the relay at "IP:ORPort" as a "bridge" relaying
into the Tor network. If "fingerprint" is provided (using the same
format as for DirAuthority), we will verify that the relay running at that
location has the right fingerprint. We also use fingerprint to look up the
bridge descriptor at the bridge authority, if it’s provided and if
UpdateBridgesFromAuthority is set too.
If "transport" is provided, and matches to a ClientTransportPlugin
line, we use that pluggable transports proxy to transfer data to the
bridge.
LearnCircuitBuildTimeout 0|1
If 0, CircuitBuildTimeout adaptive learning is
disabled. (Default: 1)
CircuitBuildTimeout NUM
Try for at most NUM seconds when building
circuits. If the circuit isn’t open in that time, give up on it. If
LearnCircuitBuildTimeout is 1, this value serves as the initial value to use
before a timeout is learned. If LearnCircuitBuildTimeout is 0, this value is
the only value used. (Default: 60 seconds)
CircuitIdleTimeout NUM
If we have kept a clean (never used) circuit
around for NUM seconds, then close it. This way when the Tor client is
entirely idle, it can expire all of its circuits, and then expire its TLS
connections. Also, if we end up making a circuit that is not useful for
exiting any of the requests we’re receiving, it won’t forever take
up a slot in the circuit list. (Default: 1 hour)
CircuitStreamTimeout NUM
If non-zero, this option overrides our
internal timeout schedule for how many seconds until we detach a stream from a
circuit and try a new circuit. If your network is particularly slow, you might
want to set this to a number like 60. (Default: 0)
ClientOnly 0|1
If set to 1, Tor will under no circumstances
run as a relay or serve directory requests. This config option is mostly
meaningless: we added it back when we were considering having Tor clients
auto-promote themselves to being relays if they were stable and fast enough.
The current behavior is simply that Tor is a client unless ORPort or DirPort
are configured. (Default: 0)
ExcludeNodes node,node,...
A list of identity fingerprints, nicknames,
country codes and address patterns of nodes to avoid when building a circuit.
(Example: ExcludeNodes SlowServer, ABCD1234CDEF5678ABCD1234CDEF5678ABCD1234,
{cc}, 255.254.0.0/8)
By default, this option is treated as a preference that Tor is allowed to
override in order to keep working. For example, if you try to connect to a
hidden service, but you have excluded all of the hidden service’s
introduction points, Tor will connect to one of them anyway. If you do not
want this behavior, set the StrictNodes option (documented below).
Note also that if you are a relay, this (and the other node selection options
below) only affects your own circuits that Tor builds for you. Clients can
still build circuits through you to any node. Controllers can tell Tor to
build circuits through any node.
Country codes are case-insensitive. The code "{??}" refers to nodes
whose country can’t be identified. No country code, including {??},
works if no GeoIPFile can be loaded. See also the GeoIPExcludeUnknown option
below.
ExcludeExitNodes node,node,...
A list of identity fingerprints, nicknames,
country codes and address patterns of nodes to never use when picking an exit
node---that is, a node that delivers traffic for you outside the Tor network.
Note that any node listed in ExcludeNodes is automatically considered to be
part of this list too. See also the caveats on the "ExitNodes"
option below.
GeoIPExcludeUnknown 0|1|auto
If this option is set to auto, then
whenever any country code is set in ExcludeNodes or ExcludeExitNodes, all
nodes with unknown country ({??} and possibly {A1}) are treated as excluded as
well. If this option is set to 1, then all unknown countries are
treated as excluded in ExcludeNodes and ExcludeExitNodes. This option has no
effect when a GeoIP file isn’t configured or can’t be found.
(Default: auto)
ExitNodes node,node,...
A list of identity fingerprints, nicknames,
country codes and address patterns of nodes to use as exit node---that is, a
node that delivers traffic for you outside the Tor network.
Note that if you list too few nodes here, or if you exclude too many exit nodes
with ExcludeExitNodes, you can degrade functionality. For example, if none of
the exits you list allows traffic on port 80 or 443, you won’t be able
to browse the web.
Note also that not every circuit is used to deliver traffic outside of the Tor
network. It is normal to see non-exit circuits (such as those used to connect
to hidden services, those that do directory fetches, those used for relay
reachability self-tests, and so on) that end at a non-exit node. To keep a
node from being used entirely, see ExcludeNodes and StrictNodes.
The ExcludeNodes option overrides this option: any node listed in both ExitNodes
and ExcludeNodes is treated as excluded.
The .exit address notation, if enabled via AllowDotExit, overrides this
option.
EntryNodes node,node,...
A list of identity fingerprints, nicknames,
and country codes of nodes to use for the first hop in your normal circuits.
Normal circuits include all circuits except for direct connections to
directory servers. The Bridge option overrides this option; if you have
configured bridges and UseBridges is 1, the Bridges are used as your entry
nodes.
The ExcludeNodes option overrides this option: any node listed in both
EntryNodes and ExcludeNodes is treated as excluded.
StrictNodes 0|1
If StrictNodes is set to 1, Tor will treat the
ExcludeNodes option as a requirement to follow for all the circuits you
generate, even if doing so will break functionality for you. If StrictNodes is
set to 0, Tor will still try to avoid nodes in the ExcludeNodes list, but it
will err on the side of avoiding unexpected errors. Specifically, StrictNodes
0 tells Tor that it is okay to use an excluded node when it is
necessary to perform relay reachability self-tests, connect to a hidden
service, provide a hidden service to a client, fulfill a .exit request, upload
directory information, or download directory information. (Default: 0)
FascistFirewall 0|1
If 1, Tor will only create outgoing
connections to ORs running on ports that your firewall allows (defaults to 80
and 443; see FirewallPorts). This will allow you to run Tor as a client
behind a firewall with restrictive policies, but will not allow you to run as
a server behind such a firewall. If you prefer more fine-grained control, use
ReachableAddresses instead.
FirewallPorts PORTS
A list of ports that your firewall allows you
to connect to. Only used when FascistFirewall is set. This option is
deprecated; use ReachableAddresses instead. (Default: 80, 443)
ReachableAddresses ADDR[/MASK][:PORT]...
A comma-separated list of IP addresses and
ports that your firewall allows you to connect to. The format is as for the
addresses in ExitPolicy, except that "accept" is understood unless
"reject" is explicitly provided. For example, 'ReachableAddresses
99.0.0.0/8, reject 18.0.0.0/8:80, accept *:80' means that your firewall allows
connections to everything inside net 99, rejects port 80 connections to net
18, and accepts connections to port 80 otherwise. (Default: 'accept
*:*'.)
ReachableDirAddresses ADDR[/MASK][:PORT]...
Like ReachableAddresses, a list of
addresses and ports. Tor will obey these restrictions when fetching directory
information, using standard HTTP GET requests. If not set explicitly then the
value of ReachableAddresses is used. If HTTPProxy is set then
these connections will go through that proxy.
ReachableORAddresses ADDR[/MASK][:PORT]...
Like ReachableAddresses, a list of
addresses and ports. Tor will obey these restrictions when connecting to Onion
Routers, using TLS/SSL. If not set explicitly then the value of
ReachableAddresses is used. If HTTPSProxy is set then these
connections will go through that proxy.
The separation between ReachableORAddresses and
ReachableDirAddresses is only interesting when you are connecting
through proxies (see HTTPProxy and HTTPSProxy). Most proxies
limit TLS connections (which Tor uses to connect to Onion Routers) to port
443, and some limit HTTP GET requests (which Tor uses for fetching directory
information) to port 80.
HidServAuth onion-address auth-cookie [service-name]
Client authorization for a hidden service.
Valid onion addresses contain 16 characters in a-z2-7 plus ".onion",
and valid auth cookies contain 22 characters in A-Za-z0-9+/. The service name
is only used for internal purposes, e.g., for Tor controllers. This option may
be used multiple times for different hidden services. If a hidden service uses
authorization and this option is not set, the hidden service is not
accessible. Hidden services can be configured to require authorization using
the HiddenServiceAuthorizeClient option.
CloseHSClientCircuitsImmediatelyOnTimeout 0|1
If 1, Tor will close unfinished hidden service
client circuits which have not moved closer to connecting to their destination
hidden service when their internal state has not changed for the duration of
the current circuit-build timeout. Otherwise, such circuits will be left open,
in the hope that they will finish connecting to their destination hidden
services. In either case, another set of introduction and rendezvous circuits
for the same destination hidden service will be launched. (Default: 0)
CloseHSServiceRendCircuitsImmediatelyOnTimeout 0|1
If 1, Tor will close unfinished
hidden-service-side rendezvous circuits after the current circuit-build
timeout. Otherwise, such circuits will be left open, in the hope that they
will finish connecting to their destinations. In either case, another
rendezvous circuit for the same destination client will be launched. (Default:
0)
LongLivedPorts PORTS
A list of ports for services that tend to have
long-running connections (e.g. chat and interactive shells). Circuits for
streams that use these ports will contain only high-uptime nodes, to reduce
the chance that a node will go down before the stream is finished. Note that
the list is also honored for circuits (both client and service side) involving
hidden services whose virtual port is in this list. (Default: 21, 22, 706,
1863, 5050, 5190, 5222, 5223, 6523, 6667, 6697, 8300)
MapAddress address newaddress
When a request for address arrives to Tor, it
will transform to newaddress before processing it. For example, if you always
want connections to www.example.com to exit via torserver (where
torserver is the nickname of the server), use "MapAddress
www.example.com www.example.com.torserver.exit". If the value is prefixed
with a "*.", matches an entire domain. For example, if you always
want connections to example.com and any if its subdomains to exit via
torserver (where torserver is the nickname of the server), use
"MapAddress *.example.com *.example.com.torserver.exit". (Note the
leading "*." in each part of the directive.) You can also redirect
all subdomains of a domain to a single address. For example, "MapAddress
*.example.com www.example.com".
NOTES:
NewCircuitPeriod NUM
1.When evaluating MapAddress expressions Tor
stops when it hits the most recently added expression that matches the
requested address. So if you have the following in your torrc,
www.torproject.org will map to 1.1.1.1:
MapAddress www.torproject.org 2.2.2.2 MapAddress www.torproject.org 1.1.1.1
2.Tor evaluates the MapAddress configuration
until it finds no matches. So if you have the following in your torrc,
www.torproject.org will map to 2.2.2.2:
MapAddress 1.1.1.1 2.2.2.2 MapAddress www.torproject.org 1.1.1.1
3.The following MapAddress expression is
invalid (and will be ignored) because you cannot map from a specific address
to a wildcard address:
MapAddress www.torproject.org *.torproject.org.torserver.exit
4.Using a wildcard to match only part of a
string (as in *ample.com) is also invalid.
Every NUM seconds consider whether to build a
new circuit. (Default: 30 seconds)
MaxCircuitDirtiness NUM
Feel free to reuse a circuit that was first
used at most NUM seconds ago, but never attach a new stream to a circuit that
is too old. For hidden services, this applies to the last time a
circuit was used, not the first. (Default: 10 minutes)
MaxClientCircuitsPending NUM
Do not allow more than NUM circuits to be
pending at a time for handling client streams. A circuit is pending if we have
begun constructing it, but it has not yet been completely constructed.
(Default: 32)
NodeFamily node,node,...
The Tor servers, defined by their identity
fingerprints or nicknames, constitute a "family" of similar or
co-administered servers, so never use any two of them in the same circuit.
Defining a NodeFamily is only needed when a server doesn’t list the
family itself (with MyFamily). This option can be used multiple times. In
addition to nodes, you can also list IP address and ranges and country codes
in {curly braces}.
EnforceDistinctSubnets 0|1
If 1, Tor will not put two servers whose IP
addresses are "too close" on the same circuit. Currently, two
addresses are "too close" if they lie in the same /16 range.
(Default: 1)
SOCKSPort [address:]port|auto [flags]
[isolation flags]
Open this port to listen for connections from
SOCKS-speaking applications. Set this to 0 if you don’t want to allow
application connections via SOCKS. Set it to "auto" to have Tor pick
a port for you. This directive can be specified multiple times to bind to
multiple addresses/ports. (Default: 9050)
The isolation flags arguments give Tor rules for which streams received
on this SOCKSPort are allowed to share circuits with one another. Recognized
isolation flags are:
IsolateClientAddr
SOCKSListenAddress IP[:PORT]
Don’t share circuits with streams from a
different client address. (On by default and strongly recommended; you can
disable it with NoIsolateClientAddr.)
IsolateSOCKSAuth
Don’t share circuits with streams for
which different SOCKS authentication was provided. (On by default; you can
disable it with NoIsolateSOCKSAuth.)
IsolateClientProtocol
Don’t share circuits with streams using
a different protocol. (SOCKS 4, SOCKS 5, TransPort connections, NATDPort
connections, and DNSPort requests are all considered to be different
protocols.)
IsolateDestPort
Don’t share circuits with streams
targetting a different destination port.
IsolateDestAddr
Don’t share circuits with streams
targetting a different destination address.
SessionGroup=INT
If no other isolation rules would prevent it,
allow streams on this port to share circuits with streams from every other
port with the same session group. (By default, streams received on different
SOCKSPorts, TransPorts, etc are always isolated from one another. This option
overrides that behavior.)
Other recognized _flags_ for a SOCKSPort are: **NoIPv4Traffic**;; Tell exits to not connect to IPv4 addresses in response to SOCKS requests on this connection. **IPv6Traffic**;; Tell exits to allow IPv6 addresses in response to SOCKS requests on this connection, so long as SOCKS5 is in use. (SOCKS4 can't handle IPv6.) **PreferIPv6**;; Tells exits that, if a host has both an IPv4 and an IPv6 address, we would prefer to connect to it via IPv6. (IPv4 is the default.) +
NOTE: Although this option allows you to specify an IP address other than localhost, you should do so only with extreme caution. The SOCKS protocol is unencrypted and (as we use it) unauthenticated, so exposing it in this way could leak your information to anybody watching your network, and allow anybody to use your computer as an open proxy. **CacheIPv4DNS**;; Tells the client to remember IPv4 DNS answers we receive from exit nodes via this connection. (On by default.) **CacheIPv6DNS**;; Tells the client to remember IPv6 DNS answers we receive from exit nodes via this connection. **CacheDNS**;; Tells the client to remember all DNS answers we receive from exit nodes via this connection. **UseIPv4Cache**;; Tells the client to use any cached IPv4 DNS answers we have when making requests via this connection. (NOTE: This option, along UseIPv6Cache and UseDNSCache, can harm your anonymity, and probably won't help performance as much as you might expect. Use with care!) **UseIPv6Cache**;; Tells the client to use any cached IPv6 DNS answers we have when making requests via this connection. **UseDNSCache**;; Tells the client to use any cached DNS answers we have when making requests via this connection. **PreferIPv6Automap**;; When serving a hostname lookup request on this port that should get automapped (according to AutomapHostsOnResove), if we could return either an IPv4 or an IPv6 answer, prefer an IPv6 answer. (On by default.) **PreferSOCKSNoAuth**;; Ordinarily, when an application offers both "username/password authentication" and "no authentication" to Tor via SOCKS5, Tor selects username/password authentication so that IsolateSOCKSAuth can work. This can confuse some applications, if they offer a username/password combination then get confused when asked for one. You can disable this behavior, so that Tor will select "No authentication" when IsolateSOCKSAuth is disabled, or when this option is set.
Bind to this address to listen for connections
from Socks-speaking applications. (Default: 127.0.0.1) You can also specify a
port (e.g. 192.168.0.1:9100). This directive can be specified multiple times
to bind to multiple addresses/ports. (DEPRECATED: As of 0.2.3.x-alpha, you can
now use multiple SOCKSPort entries, and provide addresses for SOCKSPort
entries, so SOCKSListenAddress no longer has a purpose. For backward
compatibility, SOCKSListenAddress is only allowed when SOCKSPort is just a
port number.)
SocksPolicy policy,policy,...
Set an entrance policy for this server, to
limit who can connect to the SocksPort and DNSPort ports. The policies have
the same form as exit policies below.
SocksTimeout NUM
Let a socks connection wait NUM seconds
handshaking, and NUM seconds unattached waiting for an appropriate circuit,
before we fail it. (Default: 2 minutes)
TokenBucketRefillInterval NUM [msec|second]
Set the refill interval of Tor’s token
bucket to NUM milliseconds. NUM must be between 1 and 1000, inclusive. Note
that the configured bandwidth limits are still expressed in bytes per second:
this option only affects the frequency with which Tor checks to see whether
previously exhausted connections may read again. (Default: 100 msec)
TrackHostExits host,.domain,...
For each value in the comma separated list,
Tor will track recent connections to hosts that match this value and attempt
to reuse the same exit node for each. If the value is prepended with a '.', it
is treated as matching an entire domain. If one of the values is just a '.',
it means match everything. This option is useful if you frequently connect to
sites that will expire all your authentication cookies (i.e. log you out) if
your IP address changes. Note that this option does have the disadvantage of
making it more clear that a given history is associated with a single user.
However, most people who would wish to observe this will observe it through
cookies or other protocol-specific means anyhow.
TrackHostExitsExpire NUM
Since exit servers go up and down, it is
desirable to expire the association between host and exit server after NUM
seconds. The default is 1800 seconds (30 minutes).
UpdateBridgesFromAuthority 0|1
When set (along with UseBridges), Tor will try
to fetch bridge descriptors from the configured bridge authorities when
feasible. It will fall back to a direct request if the authority responds with
a 404. (Default: 0)
UseBridges 0|1
When set, Tor will fetch descriptors for each
bridge listed in the "Bridge" config lines, and use these relays as
both entry guards and directory guards. (Default: 0)
UseEntryGuards 0|1
If this option is set to 1, we pick a few
long-term entry servers, and try to stick with them. This is desirable because
constantly changing servers increases the odds that an adversary who owns some
servers will observe a fraction of your paths. (Default: 1)
UseEntryGuardsAsDirectoryGuards 0|1
If this option is set to 1, and UseEntryGuards
is also set to 1, we try to use our entry guards as directory guards, and
failing that, pick more nodes to act as our directory guards. This helps
prevent an adversary from enumerating clients. It’s only available for
clients (non-relay, non-bridge) that aren’t configured to download any
non-default directory material. It doesn’t currently do anything when we
lack a live consensus. (Default: 1)
NumEntryGuards NUM
If UseEntryGuards is set to 1, we will try to
pick a total of NUM routers as long-term entries for our circuits. If NUM is
0, we try to learn the number from the NumEntryGuards consensus parameter, and
default to 3 if the consensus parameter isn’t set. (Default: 0)
NumDirectoryGuards NUM
If UseEntryGuardsAsDirectoryGuards is enabled,
we try to make sure we have at least NUM routers to use as directory guards.
If this option is set to 0, use the value from the NumDirectoryGuards
consensus parameter, falling back to the value from NumEntryGuards if the
consensus parameter is 0 or isn’t set. (Default: 0)
GuardLifetime N days|weeks|months
If nonzero, and UseEntryGuards is set, minimum
time to keep a guard before picking a new one. If zero, we use the
GuardLifetime parameter from the consensus directory. No value here may be
less than 1 month or greater than 5 years; out-of-range values are clamped.
(Default: 0)
SafeSocks 0|1
When this option is enabled, Tor will reject
application connections that use unsafe variants of the socks protocol —
ones that only provide an IP address, meaning the application is doing a DNS
resolve first. Specifically, these are socks4 and socks5 when not doing remote
DNS. (Default: 0)
TestSocks 0|1
When this option is enabled, Tor will make a
notice-level log entry for each connection to the Socks port indicating
whether the request used a safe socks protocol or an unsafe one (see above
entry on SafeSocks). This helps to determine whether an application using Tor
is possibly leaking DNS requests. (Default: 0)
WarnUnsafeSocks 0|1
When this option is enabled, Tor will warn
whenever a request is received that only contains an IP address instead of a
hostname. Allowing applications to do DNS resolves themselves is usually a bad
idea and can leak your location to attackers. (Default: 1)
When Tor needs to assign a virtual (unused)
address because of a MAPADDRESS command from the controller or the
AutomapHostsOnResolve feature, Tor picks an unassigned address from this
range. (Defaults: 127.192.0.0/10 and [FE80::]/10 respectively.)
When providing proxy server service to a network of computers using a tool like
dns-proxy-tor, change the IPv4 network to "10.192.0.0/10" or
"172.16.0.0/12" and change the IPv6 network to "[FC00]/7".
The default VirtualAddrNetwork address ranges on a properly configured
machine will route to the loopback or link-local interface. For local use, no
change to the default VirtualAddrNetwork setting is needed.
AllowNonRFC953Hostnames 0|1
When this option is disabled, Tor blocks
hostnames containing illegal characters (like @ and :) rather than sending
them to an exit node to be resolved. This helps trap accidental attempts to
resolve URLs and so on. (Default: 0)
AllowDotExit 0|1
If enabled, we convert
"www.google.com.foo.exit" addresses on the
SocksPort/TransPort/NATDPort into "www.google.com" addresses that
exit from the node "foo". Disabled by default since attacking
websites and exit relays can use it to manipulate your path selection.
(Default: 0)
FastFirstHopPK 0|1|auto
When this option is disabled, Tor uses the
public key step for the first hop of creating circuits. Skipping it is
generally safe since we have already used TLS to authenticate the relay and to
establish forward-secure keys. Turning this option off makes circuit building
a little slower. Setting this option to "auto" takes advice from the
authorities in the latest consensus about whether to use this feature.
Note that Tor will always use the public key step for the first hop if
it’s operating as a relay, and it will never use the public key step if
it doesn’t yet know the onion key of the first hop. (Default:
auto)
TransPort [address:]port|auto [isolation
flags]
Open this port to listen for transparent proxy
connections. Set this to 0 if you don’t want to allow transparent proxy
connections. Set the port to "auto" to have Tor pick a port for you.
This directive can be specified multiple times to bind to multiple
addresses/ports. See SOCKSPort for an explanation of isolation flags.
TransPort requires OS support for transparent proxies, such as BSDs' pf or
Linux’s IPTables. If you’re planning to use Tor as a transparent
proxy for a network, you’ll want to examine and change
VirtualAddrNetwork from the default setting. You’ll also want to set the
TransListenAddress option for the network you’d like to proxy. (Default:
0)
TransListenAddress IP[:PORT]
Bind to this address to listen for transparent
proxy connections. (Default: 127.0.0.1). This is useful for exporting a
transparent proxy server to an entire network. (DEPRECATED: As of
0.2.3.x-alpha, you can now use multiple TransPort entries, and provide
addresses for TransPort entries, so TransListenAddress no longer has a
purpose. For backward compatibility, TransListenAddress is only allowed when
TransPort is just a port number.)
NATDPort [address:]port|auto [isolation
flags]
Open this port to listen for connections from
old versions of ipfw (as included in old versions of FreeBSD, etc) using the
NATD protocol. Use 0 if you don’t want to allow NATD connections. Set
the port to "auto" to have Tor pick a port for you. This directive
can be specified multiple times to bind to multiple addresses/ports. See
SOCKSPort for an explanation of isolation flags.
This option is only for people who cannot use TransPort. (Default: 0)
NATDListenAddress IP[:PORT]
Bind to this address to listen for NATD
connections. (DEPRECATED: As of 0.2.3.x-alpha, you can now use multiple
NATDPort entries, and provide addresses for NATDPort entries, so
NATDListenAddress no longer has a purpose. For backward compatibility,
NATDListenAddress is only allowed when NATDPort is just a port number.)
AutomapHostsOnResolve 0|1
When this option is enabled, and we get a
request to resolve an address that ends with one of the suffixes in
AutomapHostsSuffixes, we map an unused virtual address to that address,
and return the new virtual address. This is handy for making
".onion" addresses work with applications that resolve an address
and then connect to it. (Default: 0)
AutomapHostsSuffixes SUFFIX,SUFFIX,...
A comma-separated list of suffixes to use with
AutomapHostsOnResolve. The "." suffix is equivalent to
"all addresses." (Default: .exit,.onion).
DNSPort [address:]port|auto [isolation flags]
If non-zero, open this port to listen for UDP
DNS requests, and resolve them anonymously. This port only handles A, AAAA,
and PTR requests---it doesn’t handle arbitrary DNS request types. Set
the port to "auto" to have Tor pick a port for you. This directive
can be specified multiple times to bind to multiple addresses/ports. See
SOCKSPort for an explanation of isolation flags. (Default: 0)
DNSListenAddress IP[:PORT]
Bind to this address to listen for DNS
connections. (DEPRECATED: As of 0.2.3.x-alpha, you can now use multiple
DNSPort entries, and provide addresses for DNSPort entries, so
DNSListenAddress no longer has a purpose. For backward compatibility,
DNSListenAddress is only allowed when DNSPort is just a port number.)
ClientDNSRejectInternalAddresses 0|1
If true, Tor does not believe any anonymously
retrieved DNS answer that tells it that an address resolves to an internal
address (like 127.0.0.1 or 192.168.0.1). This option prevents certain
browser-based attacks; don’t turn it off unless you know what
you’re doing. (Default: 1)
ClientRejectInternalAddresses 0|1
If true, Tor does not try to fulfill requests
to connect to an internal address (like 127.0.0.1 or 192.168.0.1) unless a
exit node is specifically requested (for example, via a .exit hostname, or
a controller request). (Default: 1)
DownloadExtraInfo 0|1
If true, Tor downloads and caches
"extra-info" documents. These documents contain information about
servers other than the information in their regular router descriptors. Tor
does not use this information for anything itself; to save bandwidth, leave
this option turned off. (Default: 0)
WarnPlaintextPorts port,port,...
Tells Tor to issue a warnings whenever the
user tries to make an anonymous connection to one of these ports. This option
is designed to alert users to services that risk sending passwords in the
clear. (Default: 23,109,110,143)
RejectPlaintextPorts port,port,...
Like WarnPlaintextPorts, but instead of
warning about risky port uses, Tor will instead refuse to make the connection.
(Default: None)
AllowSingleHopCircuits 0|1
When this option is set, the attached Tor
controller can use relays that have the AllowSingleHopExits option
turned on to build one-hop Tor connections. (Default: 0)
OptimisticData 0|1|auto
When this option is set, and Tor is using an
exit node that supports the feature, it will try optimistically to send data
to the exit node without waiting for the exit node to report whether the
connection succeeded. This can save a round-trip time for protocols like HTTP
where the client talks first. If OptimisticData is set to auto, Tor
will look at the UseOptimisticData parameter in the networkstatus. (Default:
auto)
Tor2webMode 0|1
When this option is set, Tor connects to
hidden services non-anonymously. This option also disables client
connections to non-hidden-service hostnames through Tor. It must only
be used when running a tor2web Hidden Service web proxy. To enable this option
the compile time flag --enable-tor2webmode must be specified. (Default:
0)
UseMicrodescriptors 0|1|auto
Microdescriptors are a smaller version of the
information that Tor needs in order to build its circuits. Using
microdescriptors makes Tor clients download less directory information, thus
saving bandwidth. Directory caches need to fetch regular descriptors and
microdescriptors, so this option doesn’t save any bandwidth for them. If
this option is set to "auto" (recommended) then it is on for all
clients that do not set FetchUselessDescriptors. (Default: auto)
UseNTorHandshake 0|1|auto
The "ntor" circuit-creation
handshake is faster and (we think) more secure than the original
("TAP") circuit handshake, but starting to use it too early might
make your client stand out. If this option is 0, your Tor client won’t
use the ntor handshake. If it’s 1, your Tor client will use the ntor
handshake to extend circuits through servers that support it. If this option
is "auto" (recommended), then your client will use the ntor
handshake once enough directory authorities recommend it. (Default:
auto)
These options override the default behavior of
Tor’s ( currently experimental) path bias detection algorithm. To
try to find broken or misbehaving guard nodes, Tor looks for nodes where more
than a certain fraction of circuits through that guard fail to get built.
The PathBiasCircThreshold option controls how many circuits we need to build
through a guard before we make these checks. The PathBiasNoticeRate,
PathBiasWarnRate and PathBiasExtremeRate options control what fraction of
circuits must succeed through a guard so we won’t write log messages. If
less than PathBiasExtremeRate circuits succeed and PathBiasDropGuards
is set to 1, we disable use of that guard.
When we have seen more than PathBiasScaleThreshold circuits through a guard, we
scale our observations by 0.5 (governed by the consensus) so that new
observations don’t get swamped by old ones.
By default, or if a negative value is provided for one of these options, Tor
uses reasonable defaults from the networkstatus consensus document. If no
defaults are available there, these options default to 150, .70, .50, .30, 0,
and 300 respectively.
Similar to the above options, these options
override the default behavior of Tor’s ( currently experimental)
path use bias detection algorithm.
Where as the path bias parameters govern thresholds for successfully building
circuits, these four path use bias parameters govern thresholds only for
circuit usage. Circuits which receive no stream usage are not counted by this
detection algorithm. A used circuit is considered successful if it is capable
of carrying streams or otherwise receiving well-formed responses to RELAY
cells.
By default, or if a negative value is provided for one of these options, Tor
uses reasonable defaults from the networkstatus consensus document. If no
defaults are available there, these options default to 20, .80, .60, and 100,
respectively.
ClientUseIPv6 0|1
If this option is set to 1, Tor might connect
to entry nodes over IPv6. Note that clients configured with an IPv6 address in
a Bridge line will try connecting over IPv6 even if
ClientUseIPv6 is set to 0. (Default: 0)
ClientPreferIPv6ORPort 0|1
If this option is set to 1, Tor prefers an OR
port with an IPv6 address over one with IPv4 if a given entry node has both.
Other things may influence the choice. This option breaks a tie to the favor
of IPv6. (Default: 0)
PathsNeededToBuildCircuits NUM
Tor clients don’t build circuits for
user traffic until they know about enough of the network so that they could
potentially construct enough of the possible paths through the network. If
this option is set to a fraction between 0.25 and 0.95, Tor won’t build
circuits until it has enough descriptors or microdescriptors to construct that
fraction of possible paths. Note that setting this option too low can make
your Tor client less anonymous, and setting it too high can prevent your Tor
client from bootstrapping. If this option is negative, Tor will use a default
value chosen by the directory authorities. (Default: -1.)
Support022HiddenServices 0|1|auto
Tor hidden services running versions before
0.2.3.x required clients to send timestamps, which can potentially be used to
distinguish clients whose view of the current time is skewed. If this option
is set to 0, we do not send this timestamp, and hidden services on obsolete
Tor versions will not work. If this option is set to 1, we send the timestamp.
If this optoin is "auto", we take a recommendation from the latest
consensus document. (Default: auto)
SERVER OPTIONS¶
The following options are useful only for servers (that is, if ORPort is non-zero): Address addressThe IP address or fully qualified domain name
of this server (e.g. moria.mit.edu). You can leave this unset, and Tor will
guess your IP address. This IP address is the one used to tell clients and
other servers where to find your Tor server; it doesn’t affect the IP
that your Tor client binds to. To bind to a different address, use the
*ListenAddress and OutboundBindAddress options.
AllowSingleHopExits 0|1
This option controls whether clients can use
this server as a single hop proxy. If set to 1, clients can use this server as
an exit even if it is the only hop in the circuit. Note that most clients will
refuse to use servers that set this option, since most clients have
ExcludeSingleHopRelays set. (Default: 0)
AssumeReachable 0|1
This option is used when bootstrapping a new
Tor network. If set to 1, don’t do self-reachability testing; just
upload your server descriptor immediately. If AuthoritativeDirectory is
also set, this option instructs the dirserver to bypass remote reachability
testing too and list all connected servers as running.
BridgeRelay 0|1
Sets the relay to act as a "bridge"
with respect to relaying connections from bridge users to the Tor network. It
mainly causes Tor to publish a server descriptor to the bridge database,
rather than publishing a relay descriptor to the public directory
authorities.
ContactInfo email_address
Administrative contact information for this
relay or bridge. This line can be used to contact you if your relay or bridge
is misconfigured or something else goes wrong. Note that we archive and
publish all descriptors containing these lines and that Google indexes them,
so spammers might also collect them. You may want to obscure the fact that
it’s an email address and/or generate a new address for this
purpose.
ExitPolicy policy,policy,...
Set an exit policy for this server. Each
policy is of the form " accept|reject
ADDR[/MASK][: PORT]". If /MASK is omitted
then this policy just applies to the host given. Instead of giving a host or
network you can also use "*" to denote the universe (0.0.0.0/0).
PORT can be a single port number, an interval of ports "
FROM_PORT- TO_PORT", or "*". If PORT is
omitted, that means "*".
For example, "accept 18.7.22.69:*,reject 18.0.0.0/8:*,accept *:*"
would reject any traffic destined for MIT except for web.mit.edu, and accept
anything else.
To specify all internal and link-local networks (including 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, and 172.16.0.0/12),
you can use the "private" alias instead of an address. These
addresses are rejected by default (at the beginning of your exit policy),
along with your public IP address, unless you set the ExitPolicyRejectPrivate
config option to 0. For example, once you’ve done that, you could allow
HTTP to 127.0.0.1 and block all other connections to internal networks with
"accept 127.0.0.1:80,reject private:*", though that may also allow
connections to your own computer that are addressed to its public (external)
IP address. See RFC 1918 and RFC 3330 for more details about internal and
reserved IP address space.
This directive can be specified multiple times so you don’t have to put it
all on one line.
Policies are considered first to last, and the first match wins. If you want to
_replace_ the default exit policy, end your exit policy with either a reject
*:* or an accept *:*. Otherwise, you’re _augmenting_ (prepending to) the
default exit policy. The default exit policy is:
ExitPolicyRejectPrivate 0|1
reject *:25 reject *:119 reject *:135-139 reject *:445 reject *:563 reject *:1214 reject *:4661-4666 reject *:6346-6429 reject *:6699 reject *:6881-6999 accept *:*
Reject all private (local) networks, along
with your own public IP address, at the beginning of your exit policy. See
above entry on ExitPolicy. (Default: 1)
IPv6Exit 0|1
If set, and we are an exit node, allow clients
to use us for IPv6 traffic. (Default: 0)
MaxOnionQueueDelay NUM [msec|second]
If we have more onionskins queued for
processing than we can process in this amount of time, reject new ones.
(Default: 1750 msec)
MyFamily node,node,...
Declare that this Tor server is controlled or
administered by a group or organization identical or similar to that of the
other servers, defined by their identity fingerprints or nicknames. When two
servers both declare that they are in the same 'family', Tor clients will not
use them in the same circuit. (Each server only needs to list the other
servers in its family; it doesn’t need to list itself, but it
won’t hurt.) Do not list any bridge relay as it would compromise its
concealment.
When listing a node, it’s better to list it by fingerprint than by
nickname: fingerprints are more reliable.
Nickname name
Set the server’s nickname to 'name'.
Nicknames must be between 1 and 19 characters inclusive, and must contain only
the characters [a-zA-Z0-9].
NumCPUs num
How many processes to use at once for
decrypting onionskins and other parallelizable operations. If this is set to
0, Tor will try to detect how many CPUs you have, defaulting to 1 if it
can’t tell. (Default: 0)
ORPort [address:]PORT|auto [flags]
Advertise this port to listen for connections
from Tor clients and servers. This option is required to be a Tor server. Set
it to "auto" to have Tor pick a port for you. Set it to 0 to not run
an ORPort at all. This option can occur more than once. (Default: 0)
ORListenAddress IP[:PORT]
Tor recognizes these flags on each ORPort: **NoAdvertise**:: By default, we bind to a port and tell our users about it. If NoAdvertise is specified, we don't advertise, but listen anyway. This can be useful if the port everybody will be connecting to (for example, one that's opened on our firewall) is somewhere else. **NoListen**:: By default, we bind to a port and tell our users about it. If NoListen is specified, we don't bind, but advertise anyway. This can be useful if something else (for example, a firewall's port forwarding configuration) is causing connections to reach us. **IPv4Only**:: If the address is absent, or resolves to both an IPv4 and an IPv6 address, only listen to the IPv4 address. **IPv6Only**:: If the address is absent, or resolves to both an IPv4 and an IPv6 address, only listen to the IPv6 address.
For obvious reasons, NoAdvertise and NoListen are mutually exclusive, and IPv4Only and IPv6Only are mutually exclusive.
Bind to this IP address to listen for
connections from Tor clients and servers. If you specify a port, bind to this
port rather than the one specified in ORPort. (Default: 0.0.0.0) This
directive can be specified multiple times to bind to multiple addresses/ports.
PortForwarding 0|1
This option is deprecated; you can get the same behavior with ORPort now that it supports NoAdvertise and explicit addresses.
Attempt to automatically forward the DirPort
and ORPort on a NAT router connecting this Tor server to the Internet. If set,
Tor will try both NAT-PMP (common on Apple routers) and UPnP (common on
routers from other manufacturers). (Default: 0)
PortForwardingHelper filename|pathname
If PortForwarding is set, use this executable
to configure the forwarding. If set to a filename, the system path will be
searched for the executable. If set to a path, only the specified path will be
executed. (Default: tor-fw-helper)
PublishServerDescriptor
0|1|v1|v2|v3|bridge,...
This option specifies which descriptors Tor
will publish when acting as a relay. You can choose multiple arguments,
separated by commas.
If this option is set to 0, Tor will not publish its descriptors to any
directories. (This is useful if you’re testing out your server, or if
you’re using a Tor controller that handles directory publishing for
you.) Otherwise, Tor will publish its descriptors of all type(s) specified.
The default is "1", which means "if running as a server,
publish the appropriate descriptors to the authorities".
ShutdownWaitLength NUM
When we get a SIGINT and we’re a server,
we begin shutting down: we close listeners and start refusing new circuits.
After NUM seconds, we exit. If we get a second SIGINT, we exit
immediately. (Default: 30 seconds)
SSLKeyLifetime N
minutes|hours|days|weeks
When creating a link certificate for our
outermost SSL handshake, set its lifetime to this amount of time. If set to 0,
Tor will choose some reasonable random defaults. (Default: 0)
HeartbeatPeriod N
minutes|hours|days|weeks
Log a heartbeat message every
HeartbeatPeriod seconds. This is a log level notice message,
designed to let you know your Tor server is still alive and doing useful
things. Settings this to 0 will disable the heartbeat. (Default: 6
hours)
AccountingMax N
bytes|KBytes|MBytes|GBytes| TBytes
Never send more than the specified number of
bytes in a given accounting period, or receive more than that number in the
period. For example, with AccountingMax set to 1 GByte, a server could send
900 MBytes and receive 800 MBytes and continue running. It will only hibernate
once one of the two reaches 1 GByte. When the number of bytes gets low, Tor
will stop accepting new connections and circuits. When the number of bytes is
exhausted, Tor will hibernate until some time in the next accounting period.
To prevent all servers from waking at the same time, Tor will also wait until
a random point in each period before waking up. If you have bandwidth cost
issues, enabling hibernation is preferable to setting a low bandwidth, since
it provides users with a collection of fast servers that are up some of the
time, which is more useful than a set of slow servers that are always
"available".
AccountingStart day|week|month [day]
HH:MM
Specify how long accounting periods last. If
month is given, each accounting period runs from the time HH:MM
on the dayth day of one month to the same day and time of the next.
(The day must be between 1 and 28.) If week is given, each accounting
period runs from the time HH:MM of the dayth day of one week to
the same day and time of the next week, with Monday as day 1 and Sunday as day
7. If day is given, each accounting period runs from the time
HH:MM each day to the same time on the next day. All times are local,
and given in 24-hour time. (Default: "month 1 0:00")
RefuseUnknownExits 0|1|auto
Prevent nodes that don’t appear in the
consensus from exiting using this relay. If the option is 1, we always block
exit attempts from such nodes; if it’s 0, we never do, and if the option
is "auto", then we do whatever the authorities suggest in the
consensus (and block if the consensus is quiet on the issue). (Default:
auto)
ServerDNSResolvConfFile filename
Overrides the default DNS configuration with
the configuration in filename. The file format is the same as the
standard Unix " resolv.conf" file (7). This option, like all
other ServerDNS options, only affects name lookups that your server does on
behalf of clients. (Defaults to use the system DNS configuration.)
ServerDNSAllowBrokenConfig 0|1
If this option is false, Tor exits immediately
if there are problems parsing the system DNS configuration or connecting to
nameservers. Otherwise, Tor continues to periodically retry the system
nameservers until it eventually succeeds. (Default: 1)
ServerDNSSearchDomains 0|1
If set to 1, then we will search for addresses
in the local search domain. For example, if this system is configured to
believe it is in "example.com", and a client tries to connect to
"www", the client will be connected to "www.example.com".
This option only affects name lookups that your server does on behalf of
clients. (Default: 0)
ServerDNSDetectHijacking 0|1
When this option is set to 1, we will test
periodically to determine whether our local nameservers have been configured
to hijack failing DNS requests (usually to an advertising site). If they are,
we will attempt to correct this. This option only affects name lookups that
your server does on behalf of clients. (Default: 1)
ServerDNSTestAddresses address,address,...
When we’re detecting DNS hijacking, make
sure that these valid addresses aren’t getting redirected. If
they are, then our DNS is completely useless, and we’ll reset our exit
policy to "reject :". This option only affects name lookups
that your server does on behalf of clients. (Default: "www.google.com,
www.mit.edu, www.yahoo.com, www.slashdot.org")
ServerDNSAllowNonRFC953Hostnames 0|1
When this option is disabled, Tor does not try
to resolve hostnames containing illegal characters (like @ and :) rather than
sending them to an exit node to be resolved. This helps trap accidental
attempts to resolve URLs and so on. This option only affects name lookups that
your server does on behalf of clients. (Default: 0)
BridgeRecordUsageByCountry 0|1
When this option is enabled and BridgeRelay is
also enabled, and we have GeoIP data, Tor keeps a per-country count of how
many client addresses have contacted it so that it can help the bridge
authority guess which countries have blocked access to it. (Default: 1)
ServerDNSRandomizeCase 0|1
When this option is set, Tor sets the case of
each character randomly in outgoing DNS requests, and makes sure that the case
matches in DNS replies. This so-called "0x20 hack" helps resist some
types of DNS poisoning attack. For more information, see "Increased DNS
Forgery Resistance through 0x20-Bit Encoding". This option only affects
name lookups that your server does on behalf of clients. (Default: 1)
GeoIPFile filename
A filename containing IPv4 GeoIP data, for use
with by-country statistics.
GeoIPv6File filename
A filename containing IPv6 GeoIP data, for use
with by-country statistics.
TLSECGroup P224|P256
What EC group should we try to use for
incoming TLS connections? P224 is faster, but makes us stand out more. Has no
effect if we’re a client, or if our OpenSSL version lacks support for
ECDHE. (Default: P256)
CellStatistics 0|1
When this option is enabled, Tor writes
statistics on the mean time that cells spend in circuit queues to disk every
24 hours. (Default: 0)
DirReqStatistics 0|1
When this option is enabled, a Tor directory
writes statistics on the number and response time of network status requests
to disk every 24 hours. (Default: 1)
EntryStatistics 0|1
When this option is enabled, Tor writes
statistics on the number of directly connecting clients to disk every 24
hours. (Default: 0)
ExitPortStatistics 0|1
When this option is enabled, Tor writes
statistics on the number of relayed bytes and opened stream per exit port to
disk every 24 hours. (Default: 0)
ConnDirectionStatistics 0|1
When this option is enabled, Tor writes
statistics on the bidirectional use of connections to disk every 24 hours.
(Default: 0)
ExtraInfoStatistics 0|1
When this option is enabled, Tor includes
previously gathered statistics in its extra-info documents that it uploads to
the directory authorities. (Default: 1)
ExtendAllowPrivateAddresses 0|1
When this option is enabled, Tor routers allow
EXTEND request to localhost, RFC1918 addresses, and so on. This can create
security issues; you should probably leave it off. (Default: 0)
MaxMemInCellQueues N bytes|KB|MB|GB
This option configures a threshold above which
Tor will assume that it needs to stop queueing cells because it’s about
to run out of memory. If it hits this threshold, it will begin killing
circuits until it has recovered at least 10% of this memory. Do not set this
option too low, or your relay may be unreliable under load. This option only
affects circuit queues, so the actual process size will be larger than this.
(Default: 8GB)
DIRECTORY SERVER OPTIONS¶
The following options are useful only for directory servers (that is, if DirPort is non-zero): AuthoritativeDirectory 0|1When this option is set to 1, Tor operates as
an authoritative directory server. Instead of caching the directory, it
generates its own list of good servers, signs it, and sends that to the
clients. Unless the clients already have you listed as a trusted directory,
you probably do not want to set this option. Please coordinate with the other
admins at tor-ops@torproject.org if you think you should be a directory.
DirPortFrontPage FILENAME
When this option is set, it takes an HTML file
and publishes it as "/" on the DirPort. Now relay operators can
provide a disclaimer without needing to set up a separate webserver.
There’s a sample disclaimer in contrib/tor-exit-notice.html.
V1AuthoritativeDirectory 0|1
When this option is set in addition to
AuthoritativeDirectory, Tor generates version 1 directory and
running-routers documents (for legacy Tor clients up to 0.1.0.x).
V2AuthoritativeDirectory 0|1
When this option is set in addition to
AuthoritativeDirectory, Tor generates version 2 network statuses and
serves descriptors, etc as described in doc/spec/dir-spec-v2.txt (for Tor
clients and servers running 0.1.1.x and 0.1.2.x).
V3AuthoritativeDirectory 0|1
When this option is set in addition to
AuthoritativeDirectory, Tor generates version 3 network statuses and
serves descriptors, etc as described in doc/spec/dir-spec.txt (for Tor clients
and servers running at least 0.2.0.x).
VersioningAuthoritativeDirectory 0|1
When this option is set to 1, Tor adds
information on which versions of Tor are still believed safe for use to the
published directory. Each version 1 authority is automatically a versioning
authority; version 2 authorities provide this service optionally. See
RecommendedVersions, RecommendedClientVersions, and
RecommendedServerVersions.
NamingAuthoritativeDirectory 0|1
When this option is set to 1, then the server
advertises that it has opinions about nickname-to-fingerprint bindings. It
will include these opinions in its published network-status pages, by listing
servers with the flag "Named" if a correct binding between that
nickname and fingerprint has been registered with the dirserver. Naming
dirservers will refuse to accept or publish descriptors that contradict a
registered binding. See approved-routers in the FILES section
below.
HSAuthoritativeDir 0|1
When this option is set in addition to
AuthoritativeDirectory, Tor also accepts and serves v0 hidden service
descriptors, which are produced and used by Tor 0.2.1.x and older. (Default:
0)
HidServDirectoryV2 0|1
When this option is set, Tor accepts and
serves v2 hidden service descriptors. Setting DirPort is not required for
this, because clients connect via the ORPort by default. (Default: 1)
BridgeAuthoritativeDir 0|1
When this option is set in addition to
AuthoritativeDirectory, Tor accepts and serves router descriptors, but
it caches and serves the main networkstatus documents rather than generating
its own. (Default: 0)
MinUptimeHidServDirectoryV2 N
seconds|minutes|hours| days|weeks
Minimum uptime of a v2 hidden service
directory to be accepted as such by authoritative directories. (Default: 25
hours)
DirPort [address:]PORT|auto [flags]
If this option is nonzero, advertise the
directory service on this port. Set it to "auto" to have Tor pick a
port for you. This option can occur more than once, but only one advertised
DirPort is supported: all but one DirPort must have the NoAdvertise
flag set. (Default: 0)
DirListenAddress IP[:PORT]
The same flags are supported here as are supported by ORPort.
Bind the directory service to this address. If
you specify a port, bind to this port rather than the one specified in
DirPort. (Default: 0.0.0.0) This directive can be specified multiple times to
bind to multiple addresses/ports.
DirPolicy policy,policy,...
This option is deprecated; you can get the same behavior with DirPort now that it supports NoAdvertise and explicit addresses.
Set an entrance policy for this server, to
limit who can connect to the directory ports. The policies have the same form
as exit policies above.
FetchV2Networkstatus 0|1
If set, we try to fetch the (obsolete, unused)
version 2 network status consensus documents from the directory authorities.
No currently supported Tor version uses them. (Default: 0)
DIRECTORY AUTHORITY SERVER OPTIONS¶
RecommendedVersions STRINGSTRING is a comma-separated list of Tor
versions currently believed to be safe. The list is included in each
directory, and nodes which pull down the directory learn whether they need to
upgrade. This option can appear multiple times: the values from multiple lines
are spliced together. When this is set then
VersioningAuthoritativeDirectory should be set too.
RecommendedClientVersions STRING
STRING is a comma-separated list of Tor
versions currently believed to be safe for clients to use. This information is
included in version 2 directories. If this is not set then the value of
RecommendedVersions is used. When this is set then
VersioningAuthoritativeDirectory should be set too.
RecommendedServerVersions STRING
STRING is a comma-separated list of Tor
versions currently believed to be safe for servers to use. This information is
included in version 2 directories. If this is not set then the value of
RecommendedVersions is used. When this is set then
VersioningAuthoritativeDirectory should be set too.
ConsensusParams STRING
STRING is a space-separated list of key=value
pairs that Tor will include in the "params" line of its
networkstatus vote.
DirAllowPrivateAddresses 0|1
If set to 1, Tor will accept router
descriptors with arbitrary "Address" elements. Otherwise, if the
address is not an IP address or is a private IP address, it will reject the
router descriptor. (Default: 0)
AuthDirBadDir AddressPattern...
Authoritative directories only. A set of
address patterns for servers that will be listed as bad directories in any
network status document this authority publishes, if AuthDirListBadDirs
is set.
AuthDirBadExit AddressPattern...
Authoritative directories only. A set of
address patterns for servers that will be listed as bad exits in any network
status document this authority publishes, if AuthDirListBadExits is
set.
AuthDirInvalid AddressPattern...
Authoritative directories only. A set of
address patterns for servers that will never be listed as "valid" in
any network status document that this authority publishes.
AuthDirReject AddressPattern...
Authoritative directories only. A set of
address patterns for servers that will never be listed at all in any network
status document that this authority publishes, or accepted as an OR address in
any descriptor submitted for publication by this authority.
Authoritative directories only. These options
contain a comma-separated list of country codes such that any server in one of
those country codes will be marked as a bad directory/bad exit/invalid for
use, or rejected entirely.
AuthDirListBadDirs 0|1
Authoritative directories only. If set to 1,
this directory has some opinion about which nodes are unsuitable as directory
caches. (Do not set this to 1 unless you plan to list non-functioning
directories as bad; otherwise, you are effectively voting in favor of every
declared directory.)
AuthDirListBadExits 0|1
Authoritative directories only. If set to 1,
this directory has some opinion about which nodes are unsuitable as exit
nodes. (Do not set this to 1 unless you plan to list non-functioning exits as
bad; otherwise, you are effectively voting in favor of every declared exit as
an exit.)
AuthDirRejectUnlisted 0|1
Authoritative directories only. If set to 1,
the directory server rejects all uploaded server descriptors that aren’t
explicitly listed in the fingerprints file. This acts as a "panic
button" if we get hit with a Sybil attack. (Default: 0)
AuthDirMaxServersPerAddr NUM
Authoritative directories only. The maximum
number of servers that we will list as acceptable on a single IP address. Set
this to "0" for "no limit". (Default: 2)
AuthDirMaxServersPerAuthAddr NUM
Authoritative directories only. Like
AuthDirMaxServersPerAddr, but applies to addresses shared with directory
authorities. (Default: 5)
AuthDirFastGuarantee N
bytes|KBytes|MBytes|GBytes
Authoritative directories only. If non-zero,
always vote the Fast flag for any relay advertising this amount of capacity or
more. (Default: 100 KBytes)
AuthDirGuardBWGuarantee N
bytes|KBytes|MBytes| GBytes
Authoritative directories only. If non-zero,
this advertised capacity or more is always sufficient to satisfy the bandwidth
requirement for the Guard flag. (Default: 250 KBytes)
BridgePassword Password
If set, contains an HTTP authenticator that
tells a bridge authority to serve all requested bridge information. Used by
the (only partially implemented) "bridge community" design, where a
community of bridge relay operators all use an alternate bridge directory
authority, and their target user audience can periodically fetch the list of
available community bridges to stay up-to-date. (Default: not set)
V3AuthVotingInterval N minutes|hours
V3 authoritative directories only. Configures
the server’s preferred voting interval. Note that voting will
actually happen at an interval chosen by consensus from all the
authorities' preferred intervals. This time SHOULD divide evenly into a day.
(Default: 1 hour)
V3AuthVoteDelay N minutes|hours
V3 authoritative directories only. Configures
the server’s preferred delay between publishing its vote and assuming it
has all the votes from all the other authorities. Note that the actual time
used is not the server’s preferred time, but the consensus of all
preferences. (Default: 5 minutes)
V3AuthDistDelay N minutes|hours
V3 authoritative directories only. Configures
the server’s preferred delay between publishing its consensus and
signature and assuming it has all the signatures from all the other
authorities. Note that the actual time used is not the server’s
preferred time, but the consensus of all preferences. (Default: 5
minutes)
V3AuthNIntervalsValid NUM
V3 authoritative directories only. Configures
the number of VotingIntervals for which each consensus should be valid for.
Choosing high numbers increases network partitioning risks; choosing low
numbers increases directory traffic. Note that the actual number of intervals
used is not the server’s preferred number, but the consensus of all
preferences. Must be at least 2. (Default: 3)
V3BandwidthsFile FILENAME
V3 authoritative directories only. Configures
the location of the bandwidth-authority generated file storing information on
relays' measured bandwidth capacities. (Default: unset)
V3AuthUseLegacyKey 0|1
If set, the directory authority will sign
consensuses not only with its own signing key, but also with a
"legacy" key and certificate with a different identity. This feature
is used to migrate directory authority keys in the event of a compromise.
(Default: 0)
RephistTrackTime N
seconds|minutes|hours|days| weeks
Tells an authority, or other node tracking
node reliability and history, that fine-grained information about nodes can be
discarded when it hasn’t changed for a given amount of time. (Default:
24 hours)
VoteOnHidServDirectoriesV2 0|1
When this option is set in addition to
AuthoritativeDirectory, Tor votes on whether to accept relays as hidden
service directories. (Default: 1)
AuthDirHasIPv6Connectivity 0|1
Authoritative directories only. When set to 0,
OR ports with an IPv6 address are being accepted without reachability testing.
When set to 1, IPv6 OR ports are being tested just like IPv4 OR ports.
(Default: 0)
HIDDEN SERVICE OPTIONS¶
The following options are used to configure a hidden service. HiddenServiceDir DIRECTORYStore data files for a hidden service in
DIRECTORY. Every hidden service must have a separate directory. You may use
this option multiple times to specify multiple services. DIRECTORY must be an
existing directory.
HiddenServicePort VIRTPORT [TARGET]
Configure a virtual port VIRTPORT for a hidden
service. You may use this option multiple times; each time applies to the
service using the most recent hiddenservicedir. By default, this option maps
the virtual port to the same port on 127.0.0.1 over TCP. You may override the
target port, address, or both by specifying a target of addr, port, or
addr:port. You may also have multiple lines with the same VIRTPORT: when a
user connects to that VIRTPORT, one of the TARGETs from those lines will be
chosen at random.
PublishHidServDescriptors 0|1
If set to 0, Tor will run any hidden services
you configure, but it won’t advertise them to the rendezvous directory.
This option is only useful if you’re using a Tor controller that handles
hidserv publishing for you. (Default: 1)
HiddenServiceVersion version,version,...
A list of rendezvous service descriptor
versions to publish for the hidden service. Currently, only version 2 is
supported. (Default: 2)
HiddenServiceAuthorizeClient auth-type
client-name,client-name, ...
If configured, the hidden service is
accessible for authorized clients only. The auth-type can either be 'basic'
for a general-purpose authorization protocol or 'stealth' for a less scalable
protocol that also hides service activity from unauthorized clients. Only
clients that are listed here are authorized to access the hidden service.
Valid client names are 1 to 19 characters long and only use characters in
A-Za-z0-9+-_ (no spaces). If this option is set, the hidden service is not
accessible for clients without authorization any more. Generated authorization
data can be found in the hostname file. Clients need to put this authorization
data in their configuration file using HidServAuth.
RendPostPeriod N
seconds|minutes|hours|days| weeks
Every time the specified period elapses, Tor
uploads any rendezvous service descriptors to the directory servers. This
information is also uploaded whenever it changes. (Default: 1 hour)
TESTING NETWORK OPTIONS¶
The following options are used for running a testing Tor network. TestingTorNetwork 0|1If set to 1, Tor adjusts default values of the
configuration options below, so that it is easier to set up a testing Tor
network. May only be set if non-default set of DirAuthorities is set. Cannot
be unset while Tor is running. (Default: 0)
TestingV3AuthInitialVotingInterval N minutes|hours
ServerDNSAllowBrokenConfig 1 DirAllowPrivateAddresses 1 EnforceDistinctSubnets 0 AssumeReachable 1 AuthDirMaxServersPerAddr 0 AuthDirMaxServersPerAuthAddr 0 ClientDNSRejectInternalAddresses 0 ClientRejectInternalAddresses 0 CountPrivateBandwidth 1 ExitPolicyRejectPrivate 0 ExtendAllowPrivateAddresses 1 V3AuthVotingInterval 5 minutes V3AuthVoteDelay 20 seconds V3AuthDistDelay 20 seconds MinUptimeHidServDirectoryV2 0 seconds TestingV3AuthInitialVotingInterval 5 minutes TestingV3AuthInitialVoteDelay 20 seconds TestingV3AuthInitialDistDelay 20 seconds TestingAuthDirTimeToLearnReachability 0 minutes TestingEstimatedDescriptorPropagationTime 0 minutes
Like V3AuthVotingInterval, but for initial
voting interval before the first consensus has been created. Changing this
requires that TestingTorNetwork is set. (Default: 30 minutes)
TestingV3AuthInitialVoteDelay N minutes|hours
Like V3AuthVoteDelay, but for initial voting
interval before the first consensus has been created. Changing this requires
that TestingTorNetwork is set. (Default: 5 minutes)
TestingV3AuthInitialDistDelay N minutes|hours
Like V3AuthDistDelay, but for initial voting
interval before the first consensus has been created. Changing this requires
that TestingTorNetwork is set. (Default: 5 minutes)
TestingAuthDirTimeToLearnReachability N
minutes|hours
After starting as an authority, do not make
claims about whether routers are Running until this much time has passed.
Changing this requires that TestingTorNetwork is set. (Default: 30
minutes)
TestingEstimatedDescriptorPropagationTime N
minutes|hours
Clients try downloading router descriptors
from directory caches after this time. Changing this requires that
TestingTorNetwork is set. (Default: 10 minutes)
TestingMinFastFlagThreshold N
bytes|KBytes|MBytes| GBytes
Minimum value for the Fast flag. Overrides the
ordinary minimum taken from the consensus when TestingTorNetwork is set.
(Default: 0.)
SIGNALS¶
Tor catches the following signals: SIGTERMTor will catch this, clean up and sync to disk
if necessary, and exit.
SIGINT
Tor clients behave as with SIGTERM; but Tor
servers will do a controlled slow shutdown, closing listeners and waiting 30
seconds before exiting. (The delay can be configured with the
ShutdownWaitLength config option.)
SIGHUP
The signal instructs Tor to reload its
configuration (including closing and reopening logs), and kill and restart its
helper processes if applicable.
SIGUSR1
Log statistics about current connections, past
connections, and throughput.
SIGUSR2
Switch all logs to loglevel debug. You can go
back to the old loglevels by sending a SIGHUP.
SIGCHLD
Tor receives this signal when one of its
helper processes has exited, so it can clean up.
SIGPIPE
Tor catches this signal and ignores it.
SIGXFSZ
If this signal exists on your platform, Tor
catches and ignores it.
FILES¶
/etc/tor/torrcThe configuration file, which contains
"option value" pairs.
$HOME/.torrc
Fallback location for torrc, if /etc/tor/torrc
is not found.
/var/lib/tor/
The tor process stores keys and other data
here.
DataDirectory/cached-status/
The most recently downloaded network status
document for each authority. Each file holds one such document; the filenames
are the hexadecimal identity key fingerprints of the directory authorities.
Mostly obsolete.
DataDirectory/cached-consensus and/or
cached-microdesc-consensus
The most recent consensus network status
document we’ve downloaded.
DataDirectory/cached-descriptors and cached-descriptors.new
These files hold downloaded router statuses.
Some routers may appear more than once; if so, the most recently published
descriptor is used. Lines beginning with @-signs are annotations that contain
more information about a given router. The ".new" file is an
append-only journal; when it gets too large, all entries are merged into a new
cached-descriptors file.
DataDirectory/cached-microdescs and cached-microdescs.new
These files hold downloaded microdescriptors.
Lines beginning with @-signs are annotations that contain more information
about a given router. The ".new" file is an append-only journal;
when it gets too large, all entries are merged into a new cached-microdescs
file.
DataDirectory/cached-routers and cached-routers.new
Obsolete versions of cached-descriptors and
cached-descriptors.new. When Tor can’t find the newer files, it looks
here instead.
DataDirectory/state
A set of persistent key-value mappings. These
are documented in the file. These include:
DataDirectory/bw_accounting
•The current entry guards and their
status.
•The current bandwidth accounting values
(unused so far; see below).
•When the file was last written
•What version of Tor generated the state
file
•A short history of bandwidth usage, as
produced in the router descriptors.
Used to track bandwidth accounting values
(when the current period starts and ends; how much has been read and written
so far this period). This file is obsolete, and the data is now stored in the
'state' file as well. Only used when bandwidth accounting is enabled.
DataDirectory/control_auth_cookie
Used for cookie authentication with the
controller. Location can be overridden by the CookieAuthFile config option.
Regenerated on startup. See control-spec.txt for details. Only used when
cookie authentication is enabled.
DataDirectory/keys/*
Only used by servers. Holds identity keys and
onion keys.
DataDirectory/fingerprint
Only used by servers. Holds the fingerprint of
the server’s identity key.
DataDirectory/approved-routers
Only for naming authoritative directory
servers (see NamingAuthoritativeDirectory). This file lists nickname to
identity bindings. Each line lists a nickname and a fingerprint separated by
whitespace. See your fingerprint file in the DataDirectory for
an example line. If the nickname is !reject then descriptors from the
given identity (fingerprint) are rejected by this server. If it is
!invalid then descriptors are accepted but marked in the directory as
not valid, that is, not recommended.
DataDirectory/router-stability
Only used by authoritative directory servers.
Tracks measurements for router mean-time-between-failures so that authorities
have a good idea of how to set their Stable flags.
HiddenServiceDirectory/hostname
The <base32-encoded-fingerprint>.onion
domain name for this hidden service. If the hidden service is restricted to
authorized clients only, this file also contains authorization data for all
clients.
HiddenServiceDirectory/private_key
The private key for this hidden service.
HiddenServiceDirectory/client_keys
Authorization data for a hidden service that
is only accessible by authorized clients.
SEE ALSO¶
privoxy(1), torsocks(1), torify(1)BUGS¶
Plenty, probably. Tor is still in development. Please report them.AUTHORS¶
Roger Dingledine [arma at mit.edu], Nick Mathewson [nickm at alum.mit.edu].04/06/2015 | Tor |