The server is a daemon that collects credit card swipe data from Magtek reader and runs configured callbacks in order to log the data or pass the data on to another server. Credit card data is AES encrypted using a passphrase that must be provided when the server is started. This passphrase is only stored in memory. The AES encypted data is then RSA encrypted using a private/public key pair. Only the public key is stored on the server permitting only encryption. The double encrypted data is not stored locally but rather is transmitted over a encrypted SSL connection to another server. The credit card data can only be decrypted if both the AES passphrase and the private RSA key are provided. The RSA key and callback parameters are combined with the AES passphrase and a digital signature is created using a SHA512 hash such that the AES passphrase must be provided to use the RSA keys or make any callbacks.

To setup the server:

• install necessary gems using 'bundle install'
• choose a long AES passphrase
• Generate RSA keys using 'rake generate_keys'
• move conf/private.yaml off of the server to protect encryption
• edit conf/callback.yaml.example providing local and/or remote callback endpoints
• Sign the callbacks using 'rake sign_callbacks'
• run credit_card_server with appropriate permissions to USB file descriptors (e.g., as root)

The Ruby wrapper libusb

The libusb library

Magtek reader script https://github.com/aughey/magtek

Copyright (c) 2012 Derrick Parkhurst (derrick.parkhurst@gmail.com)

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