JP3350242B2 - Additional program loading method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a system for controlling and executing an embedded microcomputer for controlling a device.

[0002]

2. Description of the Related Art There is an apparatus such as a personal computer which controls an external storage device by a program stored in a ROM built in a main body, reads another additional program from a medium set by a user into a RAM, and executes the program. By comparing the version of these additional programs with the version of the built-in ROM, there is a mechanism that does not execute an incompatible additional program. Furthermore, as an example of a device that removes illegally created data and reproduces only regular data,
There is a recording / reproducing method of image data described in JP-A-4-340670.

[0003]

Conventionally, the RO built into the main body is used.
The version of the program converted to M and the first to be read into RAM
The compatibility between versions of a plurality of additional programs, such as the version of the additional program, and the version of the second additional program to be subsequently read, is not considered. Further, when a plurality of additional programs are loaded, a means for changing a part or all of a later loaded program by the previously loaded additional program is not considered. In addition, when loading the additional program, a check on the validity of the media to prevent the unauthorized use of the device by the unauthorized additional program has not been considered in the past.

[0004]

[Means for Solving the Problems]

(1) Provide a security mechanism for each medium.
(2) Each additional program is encrypted and stored in each medium. (3) The version is stored in the built-in ROM as related information for each additional program. (4) The version is stored in each additional program as information related to the built-in ROM. (5) In each additional program, a version is stored as relation information indicating compatibility between the additional programs. (6) Each additional program is provided with a subroutine for changing another additional program.

[0005]

When loading an additional program, the program is loaded and changed according to the following procedure.

(1) The medium is inspected, and if it is not a regular one, no additional program data is loaded. (2)
If the loaded data is decrypted and does not pass the check by the check code, the data is erased as invalid. (3) Supported ROM version of additional program,
Compare the version of the internal ROM for the additional program, and do not load if the internal ROM is newer than the additional program. (4) If the additional program (first additional program) of one medium already loaded is newer than the additional program (second additional program) of another medium loaded later, the first A subroutine for changing a second additional program in the additional program is called. (5) For each additional program,
There is a subroutine to change additional programs
So, if there is a problem with the first program,
If a modification is required from the second additional program, the second
Modification is possible by subroutine of additional program.
You.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings.

FIG. 2 is a block diagram of a CD-ROM drive device 120 to which the additional program loading method according to the present invention is applied. The CD-ROM drive device 120 is connected to the host CPU 9
An I / F circuit 104 for controlling communication with the host CPU 90 and a CPU 10 for controlling each component shown in FIG.
3. CD drive 1 for playing CD-ROM disk 108
07, a CD-ROM data conversion circuit 105 for converting a reproduction signal obtained from the CD drive device 107 into data, storing the converted data and storing data necessary for controlling the device.
A RAM 102, and a first ROM 106 for storing a program to be executed by the CPU 103. Also, the cartridge 100 to be packaged with respect to the CD-ROM drive device 120 is provided.
Has a second ROM 101, and the second ROM 101 can be read from the CPU 103 via the data bus 113 and the control bus 114. The CPU 103 controls the CD drive 107 via the drive control signal 117 to reproduce a predetermined position of the CD disk 108 and, at the same time, sets the output of the CD-ROM data conversion circuit 105 to be transferred to the RAM 102. The reproduced CD reproduction signal 116 is sent to the CD-ROM data conversion circuit 105, where it is converted into data as a CD-ROM and stored in the RAM 102.

The operation of the additional program loading method according to the present invention will be outlined with reference to FIG. CD drive device 12
0 decrypts the first additional program 131 encrypted and stored in the CD-ROM disk 108,
02 in the first additional program load area 130. At this time, the validity of the CD-ROM disk 108 and the validity of the encrypted data are checked, and if the data is invalid, the loading is interrupted. The ROM version D corresponding to the first additional program 131 read into the RAM 102 and the first
Compare with ROM version D shown in ROM 106. If the corresponding ROM version D of the first additional program 131 is old, it is erased as an invalid additional program.
Similarly, the second additional program 141 is also loaded into the second additional program load area 140 of the RAM 102. Further, the corresponding disc version of the second additional program is compared with the corresponding cartridge version of the first additional program 131. If the corresponding cartridge version of the first additional program is newer, the corresponding cartridge version is stored in the first additional program 131. In addition, a second additional program change subroutine is executed.

The operation of each section will be further described below.

FIG. 3 shows the format of the encrypted first additional program data 132 stored on the CD-ROM disk 108. To store additional programs on the media,
The following procedure is used. (1) Additional programs, for example,
The encryption is performed by exchanging odd and even bits. (2) A check code such as a checksum is added to the encrypted additional program.
(3) The encrypted program and the check code are stored in a predetermined portion of the medium, starting with the combined length of the encrypted program and the check code.

As shown in FIG. 5, a first additional program load area 130 of the RAM 102 stores a corresponding ROM version D
It comprises a first table 133 from the first hook to the n-th hook, and a first subroutine group 134. The first table 133 includes a corresponding ROM version D indicating the version for the built-in first ROM 106, a corresponding cartridge version indicating the version for the second additional program 141, and a first boot entry indicating the entry address of the additional program. D, second boot entry D and first boot entry
Hook D to n-th hook D are provided. The first subroutine group 134 includes a subroutine D1 to a subroutine Dm, which are the main body of the additional program. The execution of the additional program is performed by a built-in first program as shown in FIG.
In the program of the ROM 106, a portion for selecting and executing the program in the first ROM 106 and the additional program is provided in advance. When executing the additional program by the first additional program 131, the first table 13 is executed in S1.
Refer to the corresponding hook in 3. The content of the hook is S2
If the value is 0, the program on the first ROM 106 is executed without any additional program, and otherwise, the program at the address of the content of the hook is executed. For example, in the case of the first additional program 131 shown in FIG. 5, since the content of the first hook D is 0, the first ROM 10
6 is executed. On the other hand, when the subroutine address DPATCH_1 is indicated as in the second hook D, the subroutine D3 at DPATCH_1 is executed.

The additional program has a built-in first ROM 10
6 can be loaded into the RAM 102 and executed. Therefore, the program in the first ROM 106 must always be executed before loading the additional program. Therefore, the contents of the table for managing the execution of the additional program are cleared to zero. That is, as shown in FIG. 6, first, in the initial state of the first table 133, all hook addresses are cleared to 0 as shown in FIG. After loading the additional programs, the execution start addresses of the added programs are recorded as shown in FIG. Also, when an additional program with invalid data or an old version is loaded, the program in the first ROM 106 is executed, so that the contents of the table are cleared to 0 as in the initial state.

With reference to FIG. 8 , an additional program load processing procedure will be described using the first additional program as an example. S1
Check that the disk on which you want to load the additional program is legitimate. If it's fraudulent,
The process branches in S2 and ends without performing the additional program loading process. If the disc is a regular disc, the process proceeds to S3, and the additional program load area 130 is cleared to zero. this is,
During the loading process of the additional program, the first table 133 is cleared in order to prevent the interrupt program from using the additional program. The following S4
Then, the data 132 obtained by encrypting the additional program is read. In S5, the data is decrypted, and it is checked whether or not the program is a legitimate additional program by using a check code. If the result of the check is incorrect, the process branches at S6, clears the additional program area 130 to 0 at S9, and ends the load processing. If so, the corresponding ROM version D is compared with the ROM version D shown in the first ROM 106 in S7. The first additional program 131 has the first
If, for example, the version number is smaller than the ROM 106 and the version number is older than the ROM 106, the process is branched, the additional program area 130 is cleared to 0 in S9, and the loading process ends. If it is a new one, the program subroutine D1 of the address shown in the first boot entry of the first table 133 is executed in S8, and the loading process is completed.

After the first additional program 131 is loaded, the second RO
A case where the second additional program 141 is loaded from M101 will be described below.

FIG. 7 shows the contents of the second additional program 141. Like the first additional program 131, the second additional program 141 includes a second table 143 for controlling the execution of the additional program, and a second subroutine group 144 storing the substance of the program. The execution method of the additional program is the first additional program 131
Similarly, if the program of the first ROM 106 refers to the second table 143 and the content of the corresponding hook is 0, the program of the first ROM 106 is executed. Otherwise, the content of the hook is changed. The subroutine of the additional program is executed as the execution start address.

FIG. 9 shows a procedure of processing for loading the second additional program 141. In S1, it is checked whether the cartridge 100 to which the additional program is to be loaded is a regular one. If not, the process branches at S2 and ends without performing the additional program loading process. If the cartridge is a regular cartridge, the process proceeds to S3, and the additional program load area 140 is cleared to zero. This is to clear the first table 143 in order to prevent, for example, interrupt processing from using the additional program during the loading processing of the additional program. In S4, the data obtained by encrypting the additional program is read from the second ROM 101. In S5, the data is decrypted, and it is checked whether or not the program is a legitimate additional program by a check code. If the result of the inspection is incorrect, the process branches at S6,
In S9, the additional program area 140 is cleared to 0, and the load processing ends. If it is legitimate, the corresponding ROM in S7
The version C is compared with the ROM version C shown in the first ROM 106. If the second additional program 141 has, for example, a smaller version number and an older version than the first ROM 106, the program branches off, clears the additional program area 140 to 0 in S9, and ends the load processing. . If it is newer, the corresponding disk version described in the second table 143 is compared with the corresponding cartridge version described in the first table 133 in S10, and the corresponding disk version shown in the first table 133 is compared. If the cartridge version is newer, S
At 11, the subroutine D2 is executed with reference to the second boot entry D of the first additional program 131. Hereinafter, S8
Then, the program subroutine C1 of the address shown in the boot entry C of the first table 143 is executed, and the loading process is completed.

The second additional program 141 is loaded after the first additional program 131 is loaded.
If the second additional program needs to be modified due to a problem in the first program or the like, the modification can be performed by the subroutine C1 indicated by the boot entry C of the second additional program 141. On the other hand, when there is a problem in the second additional program 141 or the like and the first additional program 131 corrects the error later, the process in FIG.
The mechanism of 10 to S11 is used. That is, the corresponding cartridge version of the first additional program 131 is set to a newer version than the corresponding disk version of the second additional program 141, and the first subroutine D2 indicated by the second boot entry D of the first additional program 131 is A program for modifying the second additional program 141 may be created.

Referring to FIG. 10, the ROM version D and the ROM version C stored in the first ROM 106, the corresponding ROM version D and the corresponding cartridge version stored in the first additional program 131, and the correspondence stored in the second additional program 141 The relationship between the ROM version C and the corresponding disk version will be described. First, item 1 is the first built-in
This shows a state in which only the program stored in the ROM 106 operates. In this first ROM 106, the ROM version
D and ROM version C are 0 each. In a state where the first additional program 131 and the second additional program 141 are not required, for example, if each check code is set to an invalid value, the load is not performed. At this time, the process a does not perform the loading process.

Item 2 shows a case where a first additional program is loaded into the first ROM 106 program. At this time, the process b indicates that the ROM is created after the first ROM 106, with the corresponding ROM version D of the first additional program being set to 1;
Is loaded. Further, the second additional program 141 is not loaded because the corresponding ROM version C is set to 0 and is the same version as the first ROM 106. The corresponding cartridge version of the first additional program 131 is the second additional program 1
As the corresponding disc version of 41 is 0, the first
Of the additional program 131 is not executed.

Item 3 shows a case where the second additional program 141 is also loaded. The process c at this time is the first
Assuming that the corresponding ROM version D of the additional program is 1 and that it is created after the first ROM 106, the first additional program 131 is loaded. Since the second additional program 141 also sets the corresponding ROM version C to 1, indicating that the second additional program 141 was created after the first ROM 106, the second additional program 141 is loaded. . Since the corresponding cartridge version of the first additional program 131 is 0, which is the same as the corresponding disk version of the second additional program 141, the second boot D of the first additional program 131
Is not executed. However, the second additional program 141
Since the boot C is executed, the first additional program 131 can be rewritten and corrected by the boot C if necessary.

Item 4 is a first additional program 131,
The case where a change is made to the second additional program 141 is shown. The process d at this time is the first additional program 1
31, load the second additional program 141; First
Since the corresponding cartridge version of the additional program 131 is 1, and the corresponding disk version of the second additional program 141 is 0, the first additional program 131
Of the second additional program 141
Can be rewritten and corrected in the second boot D.

Item 5 shows a case where the first ROM 106 is updated. That is, ROM version D, ROM version C
Is set to 1. In the process e at this time, neither the first additional program 131 nor the second additional program 141 is loaded.

Item 6 shows a setting for loading an additional program into the updated first ROM 106. The process f loads the first additional program 131 because the corresponding ROM version D of the first additional program 131 is newer than the ROM version D of the first ROM 106.

[0025]

According to the present invention, since only a legitimate additional program is loaded, unauthorized use of the device can be prevented, and there is an effect of improving security. According to the present invention,
Due to the relationship between the new and old versions of the plurality of additional program loading means, the old one can be modified only by the one automatically created later, which has the effect of improving operability.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing an outline of an operation of the present invention.

FIG. 2 is a block diagram of a CD-ROM drive device according to an application example of the present invention.

FIG. 3 is an explanatory diagram showing a storage format of an additional program in a medium.

FIG. 4 is a flowchart showing processing related to execution of an additional program.

FIG. 5 is an explanatory diagram showing a structure of a first additional program.

FIG. 6 is an explanatory diagram showing an initial state and a state after loading of a first table.

FIG. 7 is an explanatory diagram showing the structure of a second additional program.
You.

FIG. 8 shows a procedure for loading a first additional program.
It is a flowchart.

FIG. 9 is a flowchart showing a procedure for loading a second additional program.

FIG. 10 is an explanatory diagram illustrating an operation of an additional program loading method according to the present invention.

Continued on the front page (72) Inventor Shinji Otsuka 292 Yoshida-cho, Totsuka-ku, Yokohama-shi, Kanagawa Pref. Hitachi, Ltd. Information and Video Media Division (72) Inventor Toshihiro Matsunaga 292 Yoshida-cho, Totsuka-ku, Yokohama-shi, Kanagawa Company Hitachi Image Information System (72) Inventor Shoichiro Funato 292 Yoshida-cho, Totsuka-ku, Yokohama, Kanagawa Pref. Hitachi, Ltd.Video Media Research Laboratory (72) Inventor Katsuhiko Watananami 292 Yoshida-cho, Totsuka-ku, Yokohama-shi, Kanagawa Japan Incorporated Hitachi Image Information Systems (72) Inventor Noritaka Nishitani Yoshida-cho, Totsuka-ku, Yokohama, Kanagawa Reference number 292 Hitachi Hitachi Software Systems, Ltd. (56) References JP-A-6-187142 (JP, A) JP-A-1-124404 (JP, A) JP-A-63-4536 (JP, A) Kaisho 59-40399 JP, A) JP flat 5-126620 (JP, A) JP Akira 64-9524 (JP, A) (58 ) investigated the field (Int.Cl. ^7, DB name) G06F 9 / 06,9 / 445

Claims (5)

(57) [Claims] 1. A microprocessor comprising a microprocessor, a ROM, and a RAM.
A method for loading a plurality of additional programs for changing a function of the ROM program in a device operated by a ROM program, wherein the plurality of additional programs are detachably mounted and mounted on the device. The first additional program obtained from the ROM and the second additional program obtained from the optical disk, by which the additional program can be loaded, and a part or all of the second additional program is added to the first additional program. Is stored, and first relation information indicating a relation between the first additional program and the second additional program is stored, and the second additional program is stored in the second additional program. Second relationship information indicating a relationship with the first additional program is stored, and based on a result of comparison between the first relationship information and the second relationship information. Executing the sub-program of the first program to change part or all of the second additional program. 2. A system comprising a microprocessor, a ROM and a RAM,
A method for loading a plurality of additional programs for changing a function of the ROM program in a device operated by a ROM program, wherein the plurality of additional programs are detachably mounted and mounted on the device. The first additional program obtained from the ROM and the second additional program obtained from the optical disk which allow the additional program to be loaded by loading the first additional program include the first additional program and the second additional program obtained from the optical disk. First relation information indicating a relation with the additional program is stored, and the second additional program includes a subprogram for changing a part or all of the first additional program; the second additional program; Second relation information indicating a relation with the first additional program is stored, and based on a result of comparison between the first relation information and the second relation information, Executing the sub-program of the second program to change part or all of the first additional program. 3. The method for loading an additional program according to claim 1, wherein said second additional program is loaded in a removable form from a ROM which can be loaded on said device to load said additional program. A method for loading an additional program, wherein the first additional program is obtained from an optical disc. 4. A method for loading an additional program according to claim 1, further comprising means for checking the legitimacy of the medium storing the additional program, wherein the additional program stored on the regular medium is loaded. And how to load additional programs. 5. The method for loading an additional program according to claim 1, further comprising: means for decrypting the encrypted additional program; and means for checking the legitimacy of the encrypted additional program. A method for loading an additional program, comprising loading a legitimate additional program.