.getxfer

| Command | Function | |---------|----------| | .putxfer | Send file to radio (reverse of .getxfer) | | .ls | List directories on radio | | .del | Delete file from radio | | .df | Show free memory space | | .exit | Exit CLI mode |

The .getxfer command is used to initiate a data transfer from the radio’s internal memory to an external device (usually a PC running the OpenTX Companion software or a custom script). It typically retrieves model data, radio settings, or firmware-related binary blobs.

To appreciate .getxfer, we must understand a fundamental problem in system analysis: memory is transient. When Process A transfers a buffer to Process B via shared memory, a pipe, or a kernel-mediated copy, the original data may be overwritten or released immediately after the transfer. Forensic analysts often arrive "after the fact," finding only pointers or empty buffers. .getxfer

Early debuggers offered breakpoints on memcpy, but they could not easily reconstruct the content of the transfer in a human-readable way. .getxfer emerged as a solution—a dedicated routine that:

This capability turned .getxfer into an essential tool for tracking data exfiltration, code injection, and even legitimate IPC in complex software. | Command | Function | |---------|----------| |

  • Behavior:

    • .getxfer is a command-line utility (and associated protocol/format) designed for fast, secure, and resumable file transfers between systems. It focuses on simplicity, cross-platform compatibility, and efficient delta transfers for large files.

    This script automatically fetches all models from a connected OpenTX radio. To appreciate

    #!/bin/bash
DEVICE="/dev/ttyACM0"
stty -F $DEVICE 115200 cs8 -cstopb -parenb

    After the transfer completes, .getxfer may read the destination buffer to confirm the copy was successful—useful for detecting corruption or anti-debugging tricks.