You are an intelligence officer and your mission, should you choose to accept it, is to make sense of a transmission that we captured on our spy satellites. In order to download the transmission dump, you must connect to the TCP server at challenge.airtime.com:2323
In order to authenticate with the server, the client must perform a handshake:
Once the server sends the success packet, it will begin sending the entire satellite dump over the socket.In order to help understand the transmission, we have stolen an excerpt of a secret document that may help.
Each packet has the following structure:
0 4 8 12
|SEQ|CHK|LEN|…LEN bytes of raw Linear PCM |
The 32-bit checksum is calculated by XOR'ing each 32-bit chunk of
the 4 byte big-endian sequence number(SEQ) and data. If LEN is
not a multiple of 4, the byte 0xAB shall be used in place of the
missing bytes only for the purpose of calculating the checksum.
Hint: Next steps will become apparent once you are able to understand the transmission.
Hint: Some interesting websites that may be useful for your mission are FFmpeg and Audacity