dupconn

dupconn is a command-line utility designed to duplicate a network connection. Its primary function is to create a copy of an existing network socket, allowing data to be sent to both the original and the duplicated connection simultaneously. This can be useful for various network debugging, monitoring, or testing scenarios where it's necessary to observe or interact with network traffic without disrupting the original connection.

The tool typically works by intercepting network packets or socket operations. When a connection is established and dupconn is applied, it creates a secondary, identical connection. Subsequent data transmitted through the original connection is then mirrored to the newly created duplicate. This effectively allows multiple processes or tools to observe the same data stream.

Usage of dupconn often involves specifying the target connection, usually by its process ID or file descriptor, and then indicating where the duplicated traffic should be sent. This could be another port on the same machine or a remote destination. Advanced configurations might allow for selective duplication or modification of the mirrored data.

While not a standard operating system utility, dupconn can be found in various open-source projects or developed as a custom tool for specific network analysis tasks. Its effectiveness relies on the ability to hook into the network stack or socket layer of the operating system. Proper implementation is crucial to avoid introducing latency or instability to the network communication.