| 摘要 |
Provided is a handy terminal whereupon security can be ensured with a simple system, even if a keyboard and a display device for executing a business program and PIN input are shared. A card reader control (23b) of a keyboard unit memory (23) detects the state of a credit card being inserted, and a detected keycode is notified from a keyboard control program (23a) to a payment program (11b) of a main board (2). A main CPU (12) calculates a program hash value that is applied to the payment program (11b) and a program hash value when the payment program (11b) is executed, and encodes and decodes the program hash values using a secret key, an encryption key, and a public key so that the program hash values will not be stolen. The main CPU (12) additionally calculates a program hash value applied to the payment program (11b) and a program hash value when the payment program (11b) is executed, and compares the respective values. |
