redir —
redirect TCP connections
redir |
[ -hinpsv
]
[-b
IP
]
[-f
TYPE
]
[-I
NAME
]
[-l
LEVEL
]
[-m
BPS
]
[-o
<1,2,3>
]
[-t
SEC
]
[-w
MSEC
]
[-x
HOST:PORT
]
[-z
BYTES
]
[SRC]:PORT
[DST]:PORT |
redir redirects TCP connections coming in on
a local port, called the client
[SRC]:PORT,
to a specified address/port combination, called the server
[DST]:PORT. Both the
SRC and
DST
arguments can be left out,
redir will then
use
0.0.0.0.
redir can be run either from inetd or as a
standalone daemon. In
--inetd mode the
listening SRC:PORT combo is handled by another process, usually
inetd, and a connected socket is handed
over to
redir via stdin. Hence only
[DST]:PORT is required in
--inetd mode. In standalone mode
redir can run either in the foreground,
-n, or in the background, detached like a
proper UNIX daemon. This is the default. When running in the foreground log
messages are also printed to stderr, unless the
-s flag is given.
Depending on how redir was compiled, not all options may be available.
Mandatory arguments to long options are mandatory for short options too.
-b,
--bind=IP- Forces
redir to pick a specific address
to bind to when it listens for connections from the server side. I.e.,
filtering the interface and address used for the proxied reply from the
server back to the client.
One mental model is to consider redir as
sitting on the the border of the Internet and a LAN. Clients connect from
the Internet side, this option tells
redir which interface (address) on the
LAN side to listen for replies from the server side (DST:PORT).
Not applicable when running in Linux's transparent proxy mode,
-p.
-h,
--help- Show built-in help text.
-f,
--ftp=TYPE- When using
redir for an FTP server,
this will cause redir to also redirect FTP connections. Type should be
specified as either "port", "pasv", or
"both", to specify what type of FTP connection to handle. Note
that --transproxy often makes one or
the other (generally port) undesirable.
-i,
--inetd- Run as a process started from
inetd(1), with
the connection passed as stdin and stdout on startup.
-I,
--ident=NAME- Specify program identity (name) to be used for TCP wrapper checks and
syslog messages.
-l,
--loglevel=LEVEL- Set log level: none, err, notice, info, debug. Default is notice.
-n,
--foreground- Run in foreground, do not detach from controlling terminal.
-p,
--transproxy- On a Linux system with transparent proxying enabled, causes
redir to make connections appear as if
they had come from their true origin. See the file transproxy.txt in the
distribution, and the Linux Documentation/networking/tproxy.txt for
details. Untested on modern Linux kernels.
-s,
--syslog- Log messages to syslog. Default, except when
-n is enabled.
-t,
--timeout=SEC- Timeout and close the connection after SEC seconds of inactivity.
-v- Show program version.
-x,
--connect- Redirects connections through an HTTP proxy which supports the CONNECT
command. Specify the address and port of the proxy using
[DST]:PORT.
--connect requires the hostname and
port which the HTTP proxy will be asked to connect to.
The following options control traffic shaping, if
redir is built with shaping enabled.
-m,
--max-bandwidth=BPS- Reduce the bandwidth to be no more than BPS bits/sec. The algorithm is
basic, the goal is to simulate a slow connection, so there is no peak
acceptance.
-o,
--wait-in-out=<1,2,3>- Apply
--max-bandwidth and
--random-wait for input(1), output(2),
or both(3).
-w,
--random-wait=MSEC- Wait between 0 and 2 x n milliseconds before each "packet". A
"packet" is a block of data read in one time by redir. A
"packet" size is always less than the bufsize (see also
--bufsize)
-z,
--bufsize=BYTES- Set the bufsize (default 4096) in bytes. Can be used combined with
--max-bandwidth or
--random-wait to simulate a slow
connection.
Command line syntax changed in v3.0. Compatibility with v2.x can be enabled
using the
--enable-compat configure option.
This enables the following options:
--laddr=ADDR
--lport=PORT
--caddr=ADDR
--cport=PORT which in v3.0 were been
replaced with
[SRC]:PORT and
[DST]:PORT.
For full compatibility, using any of these options will implicitly also enable
-n. There is currently no way to tell
redir to background itself in this mode of
operation.
inetd(1)
uredir(1)
redir was made by Nigel Metheringham and Sam
Creasey, with contributions from many others. Currently maintained at GitHub
by Joachim Wiberg.