torsocks(8)

1TORSOCKS(8)                                                        TORSOCKS(8)
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NAME

6       torsocks  —  Library  for intercepting outgoing network connections and
7       redirecting them through the Tor SOCKS proxy.
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DESCRIPTION

11       Torsocks library overloads the libc symbols use for Internet communica‐
12       tion  such as connect(2) system call. Using that technique, the library
13       sends everything through the Tor network including DNS resolution  done
14       by the application.
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16       For  DNS,  gethostbyname(3)  family functions are rerouted through Tor.
17       Please note that the ISC res_* API is currently not supported.
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19       Here is an example on how to use torsocks library with ssh(1):
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21       $  LD_PRELOAD=/path/to/libtorsocks.so  ssh  -l   kalexander   -p   1234
22       prism.nsa.gov [...]
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SHELL USAGE

26       Set LD_PRELOAD to load the library then use applications as normal. The
27       syntax to force preload of the library for different shells  is  speci‐
28       fied below:
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30       Bash, Ksh and Bourne shell:
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32       $ export LD_PRELOAD=/path/to/libtorsocks.so
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34       C Shell:
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36       $ setenv LD_PRELOAD=/path/to/libtorsocks.so
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38       This  process  can be automated (for Bash, Bourne and Korn shell users)
39       for a single command or for all commands in a shell  session  by  using
40       the torsocks(1) script.
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42       You  can  also setup torsocks(1) in such a way that all processes auto‐
43       matically use it, a very useful configuration. Please refer to the tor‐
44       socks script documentation for more information.
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ENVIRONMENT VARIABLES

48       TORSOCKS_CONF_FILE
49              This  environment variable overrides the default location of the
50              torsocks configuration file. This variable is not honored if the
51              program torsocks is embedded in is setuid.
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54       TORSOCKS_LOG_LEVEL
55              Enable  logging  level of torsocks library. By default, warnings
56              and errors are printed (level 3). Note that each level  includes
57              the lower ones except the 1 which disables any possible logging.
58              (default: 3)
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61              1   No log at all.
62              2   Error messages.
63              3   Warning messages.
64              4   Notice messages.
65              5   Debug messages.
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68       TORSOCKS_LOG_TIME
69              Control whether or not the time is added to each  logging  line.
70              (default: 1)
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73       TORSOCKS_LOG_FILE_PATH
74              If  set,  torsocks  will  log  in the file set by this variable.
75              (default: stderr)
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78       TORSOCKS_USERNAME
79              Set the username for the SOCKS5 authentication method.  Password
80              MUST be set also with the variable below.
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83       TORSOCKS_PASSWORD
84              Set  the password for the SOCKS5 authentication method. Username
85              MUST be set also with the variable above.
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88       TORSOCKS_TOR_ADDRESS
89              Set the Tor address. (default: 127.0.0.1)
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92       TORSOCKS_TOR_PORT
93              Set the Tor port. (default: 9050)
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96       TORSOCKS_ALLOW_INBOUND
97              Allow inbound connections so the application can accept and lis‐
98              ten for connections.
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101       TORSOCKS_ISOLATE_PID
102              Set  the  username  and  password  for the SOCKS5 authentication
103              method to a PID/current time based value automatically. Username
104              and Password MUST NOT be set.
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KNOWN ISSUES

108   DNS
109       Torsocks  is  not able to send DNS queries through Tor since UDP is not
110       supported. Thus, any UDP socket is denied. However,  DNS  queries  that
111       can be intercept are sent to Tor and sent back to the caller.
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113   ERRORS
114       Torsocks  might  generate  error messages and print them to stderr when
115       there are problems with the configuration file or the SOCKS negotiation
116       with  the  Tor daemon. The TORSOCKS_LOG_LEVEL environment variable con‐
117       trols that behavior as well as the log file option. Keep in  mind  that
118       this library can output on the stderr of the application.
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LIMITATIONS

122       Outgoing TCP connections can only be proxified through the Tor network.
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124       Torsocks  forces  the  libc resolver to use TCP for name queries, if it
125       does this it does it regardless of whether or not the DNS to be queried
126       is local or not.  This introduces overhead and should only be used when
127       needed.
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129       Torsocks uses ELF dynamic loader features to intercept dynamic function
130       calls  from programs in which it is embedded. As a result, non-ELF exe‐
131       cutables, or executables that make system calls directly with the  sys‐
132       tem call trap (int 0x80) are not supported.
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FILES

136       /etc/tor/torsocks.conf - default torsocks configuration file
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AUTHOR

144       David Goulet <dgoulet@ev0ke.net>
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148                               August 24th, 2013                   TORSOCKS(8)