Flash reprogramming security for vehicle computer

• US 5,787,367 A
• Filed: 07/03/1996
• Issued: 07/28/1998
• Est. Priority Date: 07/03/1996
• Status: Expired due to Term

• Current Assignee: FCA US LLC (Stellantis NV)
• Original Assignee: Chrysler Corporation (Stellantis NV)
• Inventors: Berra, Charles J.
• Primary Examiner(s): NGUYEN, TAN QUANG
• Application Number:
  US08/675,754
• Time in Patent Office: 755 Days
• Field of Search: 701/1, 701/29, 701/30, 701/31, 701/32, 701/33, 701/34, 701/35, 701/114, 701/115, 380/23, 380/25, 380/28, 380/30, 380/44, 380/49, 365/195, 455/76, 455/77, 455/95, 364/551.01
• US Class Current: 701/1
• CPC Class Codes: B60R 25/04 operating on the propulsion system, e.g. engine or drive motor
• CPC Class Codes: B60R 25/24 using electronic identifiers containing a code not memorised by the user
• CPC Class Codes: G06F 21/572 Secure firmware programming, e.g. of basic input output system [BIOS]
• CPC Class Codes: G06F 2211/007 Encryption, En-/decode, En-/decipher, En-/decypher, Scramble, (De-)compress
• CPC Class Codes: G06F 2211/1097 Boot, Start, Initialise, Power

Abstract

A system and method for providing secured programming for reprogramming on-board vehicle computer systems. The system includes an interface tool which communicates with a selected on-board computer system. The communication tool also communicates with an authorized database via a modem. The vehicle computer has a serial identification number and designated passwords stored in memory and external access to the designated passwords is denied. Upon request, the vehicle computer transmits the serial identification number to the database which looks up a designated password A that corresponds to the vehicle computer and transmits password A to the computer. If the password A received by the computer matches the password in memory, the authorized database provides encrypted data in accordance with an encryption function, password B and data values. The computer deciphers the encrypted data in accordance with a stored password B to generate data values. Reprogramming of the control software is allowed only when the encrypted data value match the data values stored in the vehicle computer.

Claims

1. A system for providing secured programming of one or more on-board vehicle computers, said system comprising:

an identification code stored in memory of a programmable vehicle computer;

a first password message stored in memory of the programmable vehicle computer;

a second password message stored in memory of the programmable vehicle computer;

a database containing programming software for programming the programmable vehicle computer, said database further providing a first password message corresponding to the identification code and a second password message;

encryption means for encrypting communication data in accordance with an encryption function and based on values provided by said second password message and a series of data values;

an interface device for communicating between the database and the programmable vehicle computer;

control means within the vehicle computer for deciphering received encrypted messages and generating deciphered data values as a function of the password message; and

means for allowing reprogramming of the software in the programmable vehicle computer when the deciphered data values match the stored data values in the programmable vehicle computer.

2. The system as defined in claim 1 wherein said first password message is provided by looking to a look-up table based on the identification code.

3. The system as defined in claim 1 wherein said identification code is unique to said vehicle computer.

4. The system as defined in claim 1 wherein said programming comprises flash programming of flash memory.

5. The system as defined in claim 1 further comprising a telecommunication modem coupled between the interface tool and the database.

6. A method of programming a programmable vehicle computer, said method comprising the steps of:

storing a first password code containing a series of first values in memory of the vehicle computer;

storing a series of data values in memory of the vehicle computer;

communicating with the vehicle computer and a database;

encrypting a series of data values as a function of the first values of the first password code to generate encrypted output values;

transmitting the encrypted output values to the vehicle computer;

deciphering the encrypted output values in accordance with the stored password values to generate received data values;

comparing the deciphered data values with the stored data values; and

allowing reprogramming of software of the vehicle computer if the deciphered data values match the stored data values.

7. The method as defined in claim 6 further comprising the steps of:

storing an identification code in memory of the programmable vehicle computer;

transmitting the identification code to the database;

looking up a second password code which corresponds to the identification code received at the database;

transmitting the second password code from the database to the vehicle computer; and

comparing the received password code with a password code stored in memory of the programmable vehicle computer.

8. The method as defined in claim 7 wherein said identification code is unique to said vehicle computer.

9. The method as defined in claim 6 further comprising the step of communicating between the vehicle computer and the database via an interface device.

10. The method as defined in claim 9 further comprising communicating between the interface device and the database via a telecommunication modem.

11. The method of providing secured programming of a programmable vehicle computer, said method comprising the steps of:

transmitting an identification code from a selected vehicle computer to an authorized database;

determining a first password code which corresponds to the identification code received at the database;

transmitting the first password code from the database to the vehicle computer;

comparing the received first password code with a first password code stored in memory of the programmable vehicle computer;

encrypting a series of data values as a function of an encryption function and a second password message;

transmitting the encrypted data to the vehicle computer;

deciphering the encrypted data as a function of a stored encryption function and a stored second password to provide deciphered data values;

comparing the deciphered data values with stored data values in memory of the programmable vehicle computer; and

allowing reprogramming of software of the vehicle computer system if the deciphered data values match the stored data values.

12. The method as defined in claim 11 wherein the step of allowing reprogramming further requires that the received first password code match the stored first password code.