ProxyChains ver. 4.2.0 README

ProxyChains is a UNIX program, that hooks network-related libc functions in dynamically linked programs via a preloaded DLL and redirects the connections through SOCKS4a/5 or HTTP proxies.

when a process forks, does a DNS lookup in the child, and then uses the ip in the parent, the corresponding ip mapping will not be found, this is because the fork can’t write back into the parents mapping table. IRSSI shows this behaviour, so you have to pass the resolved ip address to it. (you can use the proxyresolv script (requires "dig") to do so)

this means that you can’t currently use tor onion urls for irssi. to solve this issue, an external data store (file, pipe, …​) has to manage the dns <→ ip mapping. of course there has to be proper locking. shm_open, mkstemp, are possible candidates for a file based approach, the other option is to spawn some kind of server process that manages the map lookups. since connect() etc are hooked, this must not be a TCP server.

I am reluctant on doing this change, because the described behaviour seems pretty idiotic (doing a fork only for a DNS lookup), and irssi is currently the only known affected program.

Using release version

Installing on Mac OS X with homebrew

$ brew install proxychains

Running Current Source code version

# needs a working C compiler, preferably gcc
./configure
make
sudo make install

Version (4.x) removes the dnsresolver script which required a dynamically linked "dig" binary to be present with remote DNS lookup. this speeds up any operation involving DNS, as the old script had to use TCP. additionally it allows to use .onion urls when used with TOR. also it removed the broken autoconf build system with a simple Makefile. there’s a ./configure script though for convenience. it also adds support for a config file passed via command line switches/ environment variables.

Version (3.x) introduces support for DNS resolving through proxy it supports SOCKS4, SOCKS5 and HTTP CONNECT proxy servers.

• Auth-types

  • socks - "user/pass",

  • http - "basic"

• When the only way to get "outside" from your LAN is through proxy server.

• To get out from behind restrictive firewall which filters outgoing ports.

• To use two (or more) proxies in chain:

• To "proxify" some program with no proxy support built-in (like telnet)

• Access intranet from outside via proxy.

• To use DNS behind proxy.

Some cool features

  like: your_host <-->socks5 <--> http <--> socks4 <--> target_host

  proxychains nmap -sT -PO -p 80 -iR  (find some webservers through proxy)

proxychains looks for configuration in the following order:

• SOCKS5 proxy port in environment variable ${PROXYCHAINS_SOCKS5} (if set, no further configuration will be searched)

• file listed in environment variable ${PROXYCHAINS_CONF_FILE} or provided as a -f argument to proxychains script or binary.

• ./proxychains.conf

• $(HOME)/.proxychains/proxychains.conf

• /etc/proxychains.conf

see more in /etc/proxychains.conf

Usage Example

$ proxychains telnet targethost.com

Usage Example

$ proxychains -f /etc/proxychains-other.conf targethost2.com

Usage Example

$ proxyresolv targethost.com

Usage Example:

$ ssh -fN -D 4321 some.example.com
$ PROXYCHAINS_SOCKS5=4321 proxychains zsh

Usage Example:

$ export PROXY_DNS_SERVER=8.8.8.8
$ proxychains telnet targethost.com