3proxy

Features

1. General

• IPv4 / IPv6 support for incoming and outgoing connection, can be used as a proxy between IPv4 and IPv6 networks in either direction
• Unix domain sockets support
• 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
• SNI proxy (based on TLS hostname)
• TLS (SSL) server and client, 3proxy may be used as https:// type proxy or stunnel replacement
• 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 services 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) bandwidth limitation for incoming and (!)outgoing traffic
• ACL-driven traffic limitation per day, week or month for incoming and outgoing traffic
• Connection limitation and ratelimiting
• 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 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 PCRE2) 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)