Program update method and server

• US 7,849,331 B2
• Filed: 04/23/2008
• Issued: 12/07/2010
• Est. Priority Date: 11/15/2002
• Status: Expired due to Term

• Current Assignee: Panasonic Semiconductor Solutions Co., Ltd. (Winbond Electronics Corporation)
• Original Assignee: Panasonic Corporation (Panasonic Holdings Corporation)
• Inventors: Inoue, Shinji, Maeda, Takuji, Ito, Takayuki, Nemoto, Yusuke, Yamada, Yasushi, Fujiwara, Makoto, Yasui, Junichi
• Primary Examiner(s): COLIN, CARL G
• Application Number:
  US12/081,889
• Publication Number:
  US 20090138728A1
• Time in Patent Office: 958 Days
• Field of Search: 713/189, 713/191, 713/193, 713/194, 380/232, 380/239
• US Class Current: 713/193
• CPC Class Codes: G06F 21/123 by using dedicated hardware, e.g. dongles, smart cards, cryptographic processors, global positioning systems [GPS] devices
• CPC Class Codes: G06F 21/572 Secure firmware programming, e.g. of basic input output system [BIOS]
• CPC Class Codes: G06F 21/72 in cryptographic circuits

Abstract

A system including a secure LSI 1 establishes a communication path to/from a server 3 (UD1), and receives a common key-encrypted program generated by encryption with a common key and transmitted from the server 3 (UD6 and UD7). The received common key-encrypted program is decrypted to generate a raw program, and the raw program is re-encrypted with an inherent key to newly generate an inherent key-encrypted program, which is stored in an external memory.

Claims

1. A secure device including an LSI device and an external memory provided outside the LSI device, wherein

the LSI device comprises:

an inherent key storage section configured to generate and store an inherent key unique to the LSI device;

an encryption section configured to generate inherent key-encrypted information by encrypting information received from outside of the LSI device using the inherent key;

an output section configured to output the inherent key-encrypted information to the external memory; and

a boot-up state selection section configured to select either one of a first boot-up state where a sequence of processes including an encrypting process using the inherent key are performed for boot-up and a second boot-up state where a sequence of processes including decrypting process using the inherent key are performed for boot-up,

wherein the inherent key stored in the inherent key storage section becomes unchangeable after generated.

2. The secure device of claim 1, the inherent key storage section comprising:

a setting storage part configured to receive and set information indicating whether rewritable or not for a storing area of the inherent key storage section in which the inherent key is stored; and

a rewrite control part configured to selectively control rewritability of the storing area in accordance with the information set in the setting storage part,

wherein the LSI device further comprises a unrewritability setting section configured to send information indicating unrewritable for the storing area to the setting storage part when the inherent key is stored in the inherent key storage section.

3. The secure device of claim 1, wherein the inherent key-encrypted information is data encrypted with the inherent key.

4. The secure device of claim 1, wherein the inherent key-encrypted information is program encrypted with the inherent key.

5. The secure device of claim 1, further comprising:

a receiving section configured to receive from an external server common key-encrypted information which is information encrypted with a common key stored in the external server;

a common key storage section configured to store a common key identical to the common key stored in the external server; and

a converting section configured to convert information received by the receiving section,

wherein the encryption section further performs decryption process using the common key stored in the common key storage section,

wherein the converting section receives the common key-encrypted information from the receiving section, generates a second inherent key-encrypted information by, using the encryption section, decrypting the received common key-encrypted information using the common key to generate raw information and encrypting the raw information using the inherent key, and outputs the second inherent key-encrypted information to the external memory.

6. The secure device of claim 5, wherein the receiving section further receives from the external server additional information including a first HASH value which is to be calculated in case that the raw information has not been tampered with,

wherein the LSI device further comprises a HASH calculating section configured to calculate a HASH value of the raw information generated by decryption,

wherein the secure device further comprises a verification section configured to verify whether or not the raw information has been tampered with by comparing the HASH value calculated by the HASH calculating section and the first HASH value.

7. The secure device of claim 5, further comprising a delete section configured to delete the inherent key-encrypted information stored in the external memory, after the second inherent key-encrypted information has been stored in the external memory.

8. The secure device of claim 5, wherein the receiving section further receives from the external server a second HASH value for the second inherent key-encrypted information,

wherein the secure device further comprises a complete verification section configured to judge that storing the second inherent key-encrypted information has been completed when the second HASH value received by the receiving section is equal to a HASH value calculated about the second inherent key-encrypted information.

9. The secure device of claim 5, wherein the LSI device comprises a storage medium for storing a boot program for boot-up operation of the secure device,

wherein the converting section is controlled by the boot program.

10. An LSI device, comprising:

an inherent key storage section configured to generate and store an inherent key unique to the LSI device;

an encryption section configured to generate inherent key-encrypted information which is information encrypted using the inherent key;

an output section configured to output the inherent key-encrypted information to an external memory which is provided outside the LSI device; and

a boot-up state selection section configured to select either one of a first boot-up state where a sequence of processes including an encrypting process using the inherent key are performed for boot-up and a second boot-up state where a sequence of processes including decrypting process using the inherent key are performed for boot-up,

wherein the inherent key stored in the inherent key storage section becomes unchangeable after generated.

11. An encryption method in a secure device including an LSI device and an external memory provided outside the LSI device, comprising the steps of:

generating, by the LSI device, an inherent key unique to the LSI device and storing the inherent key in an inherent key storage medium;

generating inherent key-encrypted information by encrypting information received from outside of the LSI device using the inherent key;

outputting the inherent key-encrypted information to the external memory; and

selecting either one of a first boot-up state where a sequence of processes including an encrypting process using the inherent key are performed for boot-up and a second boot-up state where a sequence of processes including decrypting process using the inherent key are performed for boot-up,

wherein the inherent key stored in the inherent key storage medium becomes unchangeable after generated.