Disk drive apparatus having security function using password

• US 5,799,145 A
• Filed: 08/02/1996
• Issued: 08/25/1998
• Est. Priority Date: 12/25/1995
• Status: Expired due to Term

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation), Toshiba Corporation
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Imai, Hiroshi, Kasebayashi, Tasuku
• Primary Examiner(s): PALYS, JOSEPH E
• Application Number:
  US08/691,551
• Time in Patent Office: 753 Days
• Field of Search: 395/187.01, 395/188.01, 395/186, 395/182.04, 395/182.05, 395/489, 395/490, 395/491, 380/3, 380/4, 380/23, 711/162, 711/163, 711/164
• US Class Current: 726/19
• CPC Class Codes: G06F 21/80 in storage media based on magnetic or optical technology, e.g. disks with sectors preventing unauthorised reproduction or copying of disc-type recordable media G11B20/00
• CPC Class Codes: G11B 20/00086 Circuits for prevention of unauthorised reproduction or copying, e.g. piracy indicating unauthorised use of record carriers in general G11B23/28; scrambling for television signal recording H04N5/913; network architectures or network protocols for network security H04L63/00; cryptographic mechanisms or cryptographic arrangements for secret or secure communication H04L9/00
• CPC Class Codes: G11B 20/00152 involving a password

Abstract

Test data are written into all password data areas SDAs located on each of surfaces of a disk arranged in a disk drive apparatus. SDAs each having a low error rate are selected. A predetermined number of SDAs dispersed on the plural disk surfaces are selected as effective SDAs from the selected SDAs. Position data of these effective SDAs are registered in an EEPROM. A password is written into each of the effective SDAs in a low error rate order and the disk drive apparatus is set to a locked state. A password input by a user is compared with the password written into each of the effective SDAs to release the locked state. Therefore, when an unlock command is input, the password is read from each of the effective SDAs in the writing sequential order of the password. When the password is correctly read, the read password is compared with the password input by the user. The locked state is released only when these passwords coincide with each other.

Claims

1. A disk drive apparatus having at least one disk capable of accessing to the disk when a set password is input to the disk drive apparatus, comprising:

at least two disk surfaces with plural password data areas arranged thereon among all disk surfaces;

means for writing password data to said plural password data areas, whereby the password data areas have a backup function;

effective password data area selecting means for selecting a predetermined number of password data areas each having a low read error rate as effective password data areas from said plural password data areas such that the predetermined number of password data areas are dispersed on said at least two disk surfaces;

a rewritable non-volatile memory;

registering means for writing position data of the predetermined number of effective password data areas selected by said effective password data area selecting means into said non-volatile memory; and

means for reading the password data based on said position data written in said non-volatile memory.

2. A disk drive apparatus having at least one disk capable of accessing to the disk when a set password is input to the disk drive apparatus, comprising:

at least two disk surfaces with plural password data areas arranged thereon among all disk surfaces;

means for writing password data to said plural password data areas, whereby the password data areas have a backup function;

effective password data area selecting means for selecting a predetermined number of password data areas each having a low read error rate as effective password data areas from said plural password data areas such that the predetermined number of password data areas are dispersed on said at least two disk surfaces;

a rewritable non-volatile memory;

registering means for writing position data and an access order data of the predetermined number of effective password data areas selected by said effective password data area selecting means into said nonvolatile memory; and

means for reading the password data based on said position data and said access order data written in said non-volatile memory.

3. The disk drive apparatus according to claim 2, wherein said access order data indicates an increasing order of a read error rate in said predetermined number of effective password data areas.

4. The disk drive apparatus according to claim 2, wherein said access order data indicates an increasing order of an accessing time of said predetermined number of effective password data areas.

5. A disk drive apparatus capable of accessing to a disk when a set password is input to the disk drive apparatus, comprising:

at least one disk in which plural password data areas are arranged on an entire disk; and

means for writing password data to said plural password data areas, whereby the password data areas have a backup function, wherein the password data set in said password data areas has a counter portion for counting a number of password data setting times; and

said password data writing means increments a counting value of the counter portion set in each of the password data areas by a predetermined number at a setting time of the password data to said password data areas, writes the password data having an incremented value in the counter portion to the password data areas, performs password data reading from said password data areas, and manages a version of set password data by comparing an input password with the password data having a largest counting value of the counter portion among the password data which have been read normally.

6. An access control method of a disk drive apparatus for controlling access to a disk by verifying a password written in the disk in advance with a password input by a user, the method comprising the steps of:

writing a same password to plural password data areas dispersed on at least one disk; and

reading data from each of said plural password data areas, determining whether or not the data is read normally and comparing one of the data areas which has been read normally, with the input password to control access based on a result of comparison, wherein a value showing a number of password writing times which corresponds to each of the plural password data areas is written into the plural password data areas in said writing step; and

a password having a largest value of the number of password writing times among all passwords normally read is compared with the input password.

7. An access control method of a disk drive apparatus for controlling access to a disk by verifying a password written in the disk in advance with a password input by a user, the method comprising the steps of:

writing a same password to plural password data areas dispersed on at least one disk; and

reading data from each of said plural password data areas, determining whether or not the data is read normally and comparing one of the data areas which has been read normally, with the input password to control access based on a result of comparison, wherein the password is written into each of the plural password data areas in a predetermined sequential order in said writing step; and

the password is read from each of the password data areas in the writing sequential order and a password first normally read is compared with the input password.

8. The access control method according to claim 7, wherein said predetermined sequential order increases as a read error rate in the password data area increases.

9. The access control method according to claim 7, wherein said predetermined sequential order increases as an accessing time of the password data area increases.

10. An access control method of a disk drive apparatus for controlling access to a disk by verifying a password written in the disk in advance with a password input by a user, the method comprising the steps of:

writing a same password to plural password data areas dispersed on at least one disk; and

reading data from each of said plural password data areas, determining whether or not the data is read normally and comparing one of the data areas which has been read normally, with the input password to control access based on a result of comparison, wherein a read error rate of said plural password data areas is measured, a predetermined number of password data areas having a low error rate are selected and the password is written into said selected password data areas in said writing step and, wherein a read error rate of said plural password data areas is measured and a predetermined number of password data areas having a low error rate are uniformly selected from each of the disk surfaces in said writing step.