3proxy – Features, Installation, And Usage Guide

The versatile capabilities of 3proxy, a robust and lightweight proxy server designed for a variety of network tasks.

From basic HTTP, SOCKS, and FTP proxy functionalities to advanced features like traffic control, authentication, and encryption, 3proxy offers extensive tools for network security and management.

This guide delves into the installation, configuration, and usage of 3proxy, providing a thorough overview for cybersecurity professionals and IT administrators.

# 3APA3A 3proxy tiny proxy server
(c) 2002-2021 by Vladimir '3APA3A' Dubrovin <3proxy@3proxy.org>


Branches:
Master (stable) branch - 3proxy 0.9 
Devel branch - 3proxy 10


Download: 
 Binaries for released (master) versions (Windows, Linux)
 Binaries for devel version (Windows, Linux)
 Docker images
Archive of old versions


Windows installation:

3proxy --install 
 
 installs and starts proxy as Windows service
 (config file should be located in the same directory)

3proxy --remove 

 removes the service (should be stopped before via
 'net stop 3proxy').

To build in Linux install git and build-essential packages, use

git clone
cd 3proxy
ln -s Makefile.Linux Makefile
make
sudo make install

Default configuration (for Linux/Unix):
3proxy uses 2 configuration files:
/etc/3proxy/3proxy.cfg (before-chroot). This configuration file is executed before chroot and should not be modified.
/usr/local/3proxy/conf/3proxy.cfg symlinked from /etc/3proxy/conf/3proxy.cfg (after-chroot) is a main configuration file. Modify this file, if required.
All paths in /usr/local/3proxy/conf/3proxy.cfg are relative to chroot directory (/usr/local/3proxy). For future versions it's planned to move
3proxy chroot direcory to /var.
Log files are created in /usr/local/3proxy/logs symlinked from /var/log/3proxy.
By default, socks is started on 0.0.0.0:1080 and proxy on 0.0.0.0:3128 with basic auth, no users are added by default.

use /etc/3proxy/conf/add3proxyuser.sh script to add users.

usage: /etc/3proxy/conf/add3proxyuser.sh username password [day_limit] [bandwidth]
        day_limit - traffic limit in MB per day
        bandwidth - bandwith in bits per second 1048576 = 1Mbps

or modify /etc/3proxy/conf/ files directly.

Please read doc/html/index.html and man pages.

 Features:
  1. General
 + IPv6 support for incoming and outgoing connection,
   can be used as a proxy between IPv4 and IPv6 networks
   in either direction.
 + HTTP/1.1 Proxy with keep-alive client and server support,
          transparent proxy support.
 + HTTPS (CONNECT) proxy (compatible with HTTP/2 / SPDY)
 + Anonymous and random client IP emulation for HTTP proxy mode
 + FTP over HTTP support.
 + DNS caching with built-in resolver
 + DNS proxy
 + DNS over TCP support, redirecting DNS traffic via parent
   proxy
 + SOCKSv4/4.5 Proxy
 + SOCKSv5 Proxy
 + SOCKSv5 UDP and BIND support (fully compatible with
   SocksCAP/FreeCAP for UDP)
 + Transparent SOCKS redirection for HTTP, POP3, FTP, SMTP
 + POP3 Proxy
 + FTP proxy
 + TCP port mapper (port forwarding)
 + UDP port mapper (port forwarding)
 + SMTP proxy
 + Threaded application (no child process).
 + Web administration and statistics
 + Plugins for functionality extension
 + Native 32/64 bit application
  2. Proxy chaining and network connections
 + Can be used as a bridge between client and different proxy type
   (e.g. convert incoming HTTP proxy request from client to SOCKSv5
   request to parent server).
 + Connect back proxy support to bypass firewalls
 + Parent proxy support for any type of incoming connection
 + Username/password authentication for parent proxy(s).
 + HTTPS/SOCKS4/SOCKS5 and ip/port redirection parent support
 + Random parent selection
 + Chain building (multihop proxing)
 + Load balancing between few network connections by choosing network
   interface
  3. Logging
 + tuneable log format compatible with any log parser
 + stdout logging
 + file logging
 + syslog logging (Unix)
 + ODBC logging
 + RADIUS accounting
 + log file rotation
 + automatic log file processing with external archiver (for files)
 + Character filtering for log files
 + different log files for different servces are supported
  4. Access control
 + ACL-driven Access control by username, source IP,
 destination IP/hostname, destination port and destination action
 (POST, PUT, GET, etc), weekday and daytime.
 + ACL-driven (user/source/destination/protocol/weekday/daytime or
 combined) bandwith limitation for incoming and (!)outgoing trafic.
 + ACL-driven traffic limitation per day, week or month for incoming and
 outgoing traffic
 + Connection limitation and ratelimting
 + User authentication by username / password
 + RADIUS Authentication and Authorization
 + User authentication by DNS hostname
 + Authentication cache with possibility to limit user to single IP address
 + Access control by username/password for SOCKSv5 and HTTP/HTTPS/FTP
 + Cleartext or encrypted (crypt/MD5 or NT) passwords.
 + Connection redirection
 + Access control by requested action (CONNECT/BIND, 
   HTTP GET/POST/PUT/HEAD/OTHER).
 + All access control entries now support weekday and time limitations
 + Hostnames and * templates are supported instead of IP address
  5. Extensions
 + Regular expression filtering (with PCRE) via PCREPlugin
 + Authentication with Windows username/password (cleartext only)
 + SSL/TLS decryptions with certificate spoofing
 + Transparent redirection support for Linux and *BSD
  6. Configuration
 + support for configuration files
 + support for includes in configuration files
 + interface binding
 + socket options
 + running as daemon process
 + utility for automated networks list building
 + configuration reload on any file change
     Unix
 + support for chroot
 + support for setgid
 + support for setuid
 + support for signals (SIGUSR1 to reload configuration)
     Windows
 + support --install as service
 + support --remove as service
 + support for service START, STOP, PAUSE and CONTINUE commands (on
 PAUSE no new connection accepted, but active connections still in
 progress, on CONTINUE configuration is reloaded)
     Windows 95/98/ME
 + support --install as service
 + support --remove as service
  6. Compilation
 + MSVC (static)
 + OpenWatcom (static)
 + Intel Windows Compiler (msvcrt.dll)
 + Windows/gcc (msvcrt.dll)
 + Cygwin/gcc (cygwin.dll)
 + Unix/gcc
 + Unix/ccc
 + Solaris
 + Mac OS X, iPhone OS
 + Linux and derivered systems
 + Lite version for Windows 95/98/NT/2000/XP/2003
 + 32 bit and 64 bit versions for Windows Vista and above, Windows 2008 server and above 

3proxy     Combined proxy server may be used as
  executable or service (supports installation and removal).
  It uses config file to read it's configuration (see
  3proxy.cfg.sample for details).
  3proxy.exe is all-in-one, it doesn't require all others .exe
  to work.
  See 3proxy.cfg.sample for examples, see man 3proxy.cfg

proxy     HTTP proxy server, binds to port 3128
ftppr     FTP proxy server, binds to port 21
socks     SOCKS 4/5 proxy server, binds to port 1080
ftppr  FTP proxy server, please do not mess it with FTP over HTTP
  proxy used in browsers
pop3p     POP3 proxy server, binds to port 110. You must specify
  POP3 username as username@target.host.ip[:port]
  port is 110 by default.
  Exmple: in Username configuration for you e-mail reader
  set someuser@pop.example.org, to obtains mail for someuser
  from pop.somehost.ru via proxy.
smtpp     SMTP proxy server, binds to port 25. You must specify
  SMTP username as username@target.host.ip[:port]
  port is 25 by default.
  Exmple: in Username configuration for you e-mail reader
  set someuser@mail.example.org, to send mail as someuser
  via mail.somehost.ru via proxy.
tcppm     TCP port mapping. Maps some TCP port on local machine to
  TCP port on remote host.
udppm     UDP port mapping. Maps some UDP port on local machine to
  UDP port on remote machine. Only one user simulationeously
  can use UDP mapping, so it cann't be used for public service
  in large networks. It's OK to use it to map to DNS server
  in small network or to map Counter-Strike server for single
  client (you can use few mappings on different ports for
  different clients in last case).
mycrypt     Program to obtain crypted password fro cleartext. Supports
  both MD5/crypt and NT password.
   mycrypt password
  produces NT password
   mycrypt salt password
  produces MD5/crypt password with salt "salt".