.TH DPIBREAK 1 "September 2025" "DPIBreak v0.0.1" "User Commands" .nh .ad l .SH NAME dpibreak \- simple and efficient DPI circumvention tool in Rust. .SH SYNOPSIS .B dpibreak .RI [ OPTIONS ] .SH DESCRIPTION .B DPIBreak is a simple and efficient tool for circumventing Deep Packet Inspection (DPI), especially on HTTPS connections. It fragments the TCP packet carrying the TLS ClientHello so that certain DPI devices cannot extract the Server Name Indication (SNI) field and identify the destination site. It only applies to the first outbound segment that carries the TLS ClientHello; Other packets are not queued to userspace and pass through the kernel normally, unmodified. UDP/QUIC (HTTP/3) is not affected. This program is cross\-platform and runs the same way on both Linux and Windows. No manual firewall configuration is required: starting the program enables it system\-wide; stopping it disables it. .SH REQUIREMENTS .TP \fBLinux\fR Root privileges (or capabilities .BR CAP_NET_ADMIN and .BR CAP_NET_RAW ) are required to install iptables rules and attach to NFQUEUE. The .B iptables and .B ip6tables commands must be available. Kernel support for .BR xt_u32 and .BR nfnetlink_queue is required (these modules are typically auto\-loaded). .TP \fBWindows\fR Administrator privilege is required to open the WinDivert driver; the program opens the driver automatically at startup. .SH OPTIONS .TP .B \-\-delay\-ms \fIu64\fR Delay in milliseconds to apply between fragmented pieces of the ClientHello. Typical values are 0–1000; larger values may increase handshake latency. (default: 0) .TP .B \-\-queue\-num \fIu16\fR .Linux only. NFQUEUE number to attach to. The same queue number is used for IPv4 and IPv6. (default: 1) .TP .B \-\-loglevel \fIdebug|info|warning|error\fR Set the logging level (default: .BR warning ). Aliases: .BR warn " \-> " warning , .BR err " \-> " error . .TP .B \-\-no\-splash Disable splash messages at startup. .TP .B \-h , \-\-help Show usage information and exit. .SH EXAMPLES .PP Run with default options: .PP .RS .B dpibreak .RE .PP Run with a 10 ms delay and verbose logging: .PP .RS .B dpibreak \-\-delay\-ms 10 \-\-loglevel debug .RE .PP Use a custom NFQUEUE on Linux: .PP .RS .B dpibreak \-\-queue\-num 3 .RE .SH BUGS Although the program works reliably in the author's region and ISP, different regions, ISPs, or organizations may deploy different DPI equipment. In such cases, there is a chance that .B dpibreak does not function as expected. If you encounter such issue, please report symptoms and, if possible, packet capture logs (e.g., collected with Wireshark) or hints such as cases where alternative tools like GoodByeDPI succeed with specific settings to the bug tracker listed below. .PP When sharing packet capture logs, please make sure they do not contain sensitive personal information (e.g., passwords or session cookies). It is usually enough to capture only the initial handshake packets showing the issue, rather than full sessions. .PP Any other problems not covered above are also appreciated. Report bugs at . .SH SECURITY AND PRIVACY The program does not store or transmit your traffic. Fragmentation is performed locally on the host; no external proxy or relay is used. .SH EXIT STATUS Normally, \fBdpibreak\fR runs continuously until interrupted by the user (e.g. with Ctrl+c) or the system. In such cases it exits with status 0. Non\-zero exit codes are returned if the program fails to start (for example, due to insufficient privileges, missing iptables/WinDivert, or invalid options). .SH SEE ALSO .BR iptables (8), .BR ip6tables (8), .BR tcpdump (1), .BR wireshark (1) .PP GoodByeDPI .SH AUTHOR Written by Dilluti0n .