CN100385421C - Method for preventing rewriting to programmable chip software - Google Patents

Method for preventing rewriting to programmable chip software Download PDF

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CN100385421C
CN100385421C CN 00118317 CN00118317A CN100385421C CN 100385421 C CN100385421 C CN 100385421C CN 00118317 CN00118317 CN 00118317 CN 00118317 A CN00118317 A CN 00118317A CN 100385421 C CN100385421 C CN 100385421C
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address
write
programmable
register
chip
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CN1328294A (en
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陈宇光
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华硕电脑股份有限公司
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Abstract

一种可编程芯片软件防写保护的方法,应用在电脑系统中的可编程芯片的暂存器。 A programmable chip software write-protect method, in a computer system application programmable chip register. 当电脑系统中可编程芯片的暂存器设定完毕后,依照所设定功能执行工作,不允许任意修改可编程芯片的暂存器的内容。 When the computer system chip programmable register setting is completed, in accordance with the function set implementation, does not allow any of the content of the register of the programmable chip. 当病毒将可编程芯片写入错误的参数时,中断服务程序更改病毒指令的内容,可避免可编程芯片的暂存器的内容被修改。 Programmable chip when the virus will write error parameters, the contents of the interrupt service routine instructions to change the virus can be avoided programmable chip register content is modified. 因此采用软件的方式来达到防止资料写入暂存器的目的,使电脑系统不会产生不稳定的情况,并且提升电脑系统的稳定度。 Therefore, using software approach to achieve the purpose of preventing data written to the scratchpad, the computer system will not produce instability, and enhance the stability of computer systems.

Description

可编程芯片软件防写保护的方法技术领域本发明涉及可编程(programmable)芯片的防写保护方法,特别涉及采用软件来达到防止不正确资料写入可编程芯片的暂存器的保护方法。 Programmable chip software write-protect TECHNICAL FIELD The present invention relates to a programmable (Programmable) chip write-protect method, and in particular relates to incorrect information in software programmable chip register write protection method to achieve the prevention. 背景技术以往许多可编程芯片组(chipset)或IC是没有提供保护机制的,但是没有保护是非常危险的事,就病毒程序为例,当病毒将可编程芯片写入错误的参数时,将使系统发生当机或不稳定的现象。 Background Art Many programmable chipset (chipset) or IC is no protection mechanism, but no protection is a very dangerous thing, for example on the virus program, programmable chip when the virus will write error parameters will phenomenon or unstable system crash occurs. 对于封闭式系统,上述的情况是不会发生的,但对于开放式系统而言,除了所规定的修改程序之外,不可任意修改可编程芯片的暂存器的资料是非常重要的。 For the closed system, the above situation is not going to happen, but for open systems, in addition to modify the program as defined, can not be arbitrarily modified chip programmable register information is very important. 图1示出现有技术的电脑的基本结构图。 FIG 1 a prior art basic structure shown in FIG computer appears. 如图1所示,CPU 10、主存储器12及影像加速卡14连接至北桥芯片16,周边设备22连接至南桥芯片20, 北桥芯片16与南桥芯片20再互相连接,如此,将概略地描述电脑系统的基本架构。 As illustrated, CPU 10, main memory 12 and the video accelerator card 14 is connected to the north bridge chip 16, a peripheral device 22 is connected to the south bridge chip 20, a north bridge chip 16 and the south bridge chip 20 and then connected to each other, so the schematically describe the basic architecture of a computer system. 当电脑开机时,即CPU10开始工作,CPU 10会寻找要执行的第一个指令的所在的地址,而其地址是在主机板上BIOS(Basic Input Output System)快闪存储器中的开机程序的地址,CPU IO便开始执行开机程序。 When the address is the address where the computer is turned on, namely CPU10 begin work, CPU 10 will look for the first instruction to be executed, and its address is BIOS (Basic Input Output System) on the system board flash memory boot program , CPU IO will begin the boot process. 这时,开机程序检查电脑中所有的标准元件(如主存储器12等)是否存在,同时检查其功能是否正常。 In this case, the boot program checks all standard components (e.g., main memory 12, etc.) in the presence or absence of a computer, while checking its functionality. 在做检查工作之前,先将中断向量表的前十六栏指标改为指向主机板中BIOS的中断服务例行程序(Interrupt Service Routine),完成这样的程序之后,开机程序才会启动屏蔽(mask)式中断,如此, 电脑才会有所回应,如键盘的按键訊号。 After checking before doing the work, the first change to the interrupt vector table top sixteen bar indicators pointing in the motherboard BIOS interrupt service routine (Interrupt Service Routine), the completion of such a program, the boot process will start the mask (mask ) type interrupt, so the computer will have to respond, such as a keyboard key signal. 之后,开机程序会检查介面卡是否有BIOS芯片。 After that, the boot process will check whether there interface card BIOS chip. 例如检查到加速影像卡14上有影像BIOS芯片(未示出),开机程序会将电脑的控制杈转移给影像BIOS芯片中的程序,让这个程序可在中断向量表的适当栏位放入中断服务例行程序的地址,当执行影像BIOS芯片中的程序时,便将资料显示在萤幕上。 For example, a video accelerator card 14 to check an image with BIOS chip (not shown), the boot process will be transferred to the computer control program bifurcation video BIOS chip, so that the program can be placed in the interrupt in the interrupt vector table appropriate fields service routine address, when program execution video BIOS chip, put the information displayed on the screen. 当完成上述的动作时,电脑的控制杈便会还给主机板上BIOS的开机程 Upon completion of the above operation, the computer will return control of bifurcation on the motherboard BIOS boot process

同样地,主机板上BIOS的开机程序会设定可編程芯片(如北桥芯片16 及南桥芯片20)内的各种暂存器,让可編程芯片得知与那些设备相连接,必须执行那些工作,当CPU10耍与主存储器12或周边设备22传输资料时, 便可以由所设定的可编程芯片完成其工作。 Likewise, the motherboard BIOS boot program setting various registers within the programmable chip (such as Northbridge 16 and Southbridge 20), so that the chip is connected to the programmable those devices that must be performed in operation, when CPU10 playing the main memory 12 or the peripheral device 22 data transfer, it can be performed by a programmable chip set its work. 电脑系统使用可編程芯片的优点为:1.同一个可编程芯片具有多种功能的选择,以适应系统不同的要求,只需要更新可編程芯片中的程序即可。 The advantage of using a programmable computer chip system: 1 having a single programmable chip select various functions, to accommodate different system requirements, only needs to update the programmable chip. 2.可以调整可編程芯片中各种功能的暂存器的各种参数,以适应系统不同的周边设备,例如南桥芯片,只需调整暂存器的参数就可外接磁碟机或扫描器等周边设备。 2. can adjust various parameters in the programmable registers of the various chip functions of the system to adapt to different peripherals, for example, a south bridge chip, and only the adjustment parameter register can drive or an external scanner and other peripheral equipment. 然而,当可編程芯片完成设定后,是不允许任意修改的,亦即可編程芯片内的各种功能的暂存器所储存的数值是不可任意修改的。 However, after completion of setting programmable chips, it can not be modified any, i.e. register various functions within the programmable values ​​stored in the chip can not be arbitrarily modified. 因为修改这些暂存器所储存的数值会改变连接设备或工作状态,例如:当CPU10要与主存储器12或周边设备22传输资料时,可能造成资料传送错误或执行工作错误, 使得系统停滞或不稳定的情况发生。 Because modifications to these registers will change the value stored in the device or connected to the working status, for example: when the CPU10 to the main memory 12 or the peripheral device 22 transmit data, transmission errors may cause data errors or work performed, so that the system does not stagnate or in stable condition occurs. 因此,现有技术采用一种硬体的方式来解决上述的问题,其方式是要修改可编程芯片中某一个暂存器的数值时,必须先做写入特定的暂存器的动作,而且必须重复做写入的动作,其重复的次数必须达到预定的次数后才可以修改欲修改的暂存器。 Thus, using the prior art way of hardware to solve the above problems, in a manner that when the operation to modify the value of a register of a programmable chip, must first write the specific register, and repeat the action must be written, the number of repetitions must reach a predetermined number of times before they can modify the register to be modified. 例如:要修改可编程芯片中第三个暂存器的数值,先写入任意的数值于第七个暂存器,而且重复写入五次,然后再将修改的数值写入第三个暂存器,如此,才完成了修改暂存器的数值。 For example: To change the value in the third register programmable chips, the first write any value to the seventh register, and writing is repeated five times, and then the modified value is written to the third temporary register, thus, to complete the modification value of the register. 然而,上述的方式有其缺点,当使用者在执行应用程序时,由于人为的因素,如暂存器的误用或指令的执行错误等,发生写入错误地址而导致可编程芯片的暂存器的数值被修改;或者熟悉上述的方式的程序设计师撰写病毒程序,当病毒程序进入系统且执行此程序时,病毒程序就会修改可编程芯片的暂存器的数值,都将造成系统的紊乱,使得系统发生停滞或不稳定的情况。 However, the above embodiment has the disadvantage, while the user is executing an application program, due to human factors, such as the misuse or execution errors instruction register, the write address generating an error caused by temporary programmable chip value is to be modified; or the above-described manner familiar to programmers to write virus programs, when the virus enters the system program and the program is executed, the virus program will change the value of the register programmable chips, will cause the system to disorders, such that the system occurs arrest or unstable. 总结上述的缺点有:(l)当执行应用程序时,由于暂存器的误用或执行结果错误而发生可编程芯片中的暂存器的资料被修改;(2)当病毒程序被执行时,进行修改可編程芯片中的暂存器的资料,都会造成系统停滞或不稳定。 Summarizing the above disadvantages are: (l) when the application is executed, since the chip programmable data register occurs misuse or erroneous execution result register is modified; (2) when the program is executed the virus , modify programmable chip scratchpad data, will result in system instability or stagnation. 发明内容 SUMMARY

本发明所提出的方法是应用在电脑系统中的可編程芯片的暂存器,而泉用软件的方式来防止资料任意存入暂存器内,以保护电脑系统。 The method proposed in the present invention is the use of a programmable computer system chip register, and springs to use software to prevent any data stored in the register, in order to protect the computer system. 本发明提出一种可編程芯片软件防写保护的方法,系应用于电脑系统, 在电脑系统的基本输入输出系统中包括:首先,撰写一个中断服务程序。 The present invention proposes a method of software programmable chip write-protected, used in computer-based system, the basic input output system in a computer system comprising: a first write an interrupt service routine. 以及,建立一个指标表。 And to establish an indicator table. 本发明提出一种可编程芯片软件防写保护的方法,系应用于电脑系统中,在电脑系统中包括可編程芯片,可编程芯片中包括指标暂存器。 The present invention proposes a method of software programmable chip write-protected, used in computer-based system, the computer system includes a programmable chip, the chip includes a programmable index register. 该方法包括步骤:提供一中断服务程序及一指标表于该电脑系统中,该指标表包含该指标暂存器中的至少一禁止写入地址;当CPU读取到一写入该可编程芯片的指标暂存器的指令时,执行该中断服务程序并且读入该指标表.;该中断服务程序判断该指令的写入指标暂存器的地址是否属于该指标表的该禁止写入地址;当判断结果属于该禁止写入地址时,修改该指令所写入的该指标暂存器的地址为一不属于该禁止写入地址的替代地址;和根据该替代地址,执行该指令。 The method comprising the steps of: providing an interrupt service routine and an indicator table in the computer system, the index table containing the index register is prohibited in at least one write address; when the CPU reads a write to the programmable chip the index register instruction is executed and the interrupt service routine reads the index table; the interrupt service routine determines the write pointer register the address of the instruction belongs to the prohibition of the write address indicator table; when the determination result belongs to prohibit write address, the instruction to modify the index register address is written in a substitute address that does not belong to prohibit the write address; and according to the alternative address, the instruction is executed. 所述的可编程芯片软件防写保护的方法,其中该中断服务程序及该地址表的步骤中,还包括设定一中断向量值,以作为该中断服务程序的起始地址。 The programmable chip software write-protect method, wherein the step of interrupt service routine address table and said, further comprising setting an interrupt vector value, as the start address of the interrupt service routine. 为让本发明的上述目的、特征、和优点能更明显易懂,下文特举较佳实施例,并配合所附图式,作详细说明如下。 In order to make the above-described object of the present invention, features, and advantages can be more fully understood by referring give the preferred embodiments and accompanying figures, described in detail below. 附图说明图1示出现有技术的电脑的基本架抅图; 图2示出建立指标表及中断服务程序的流程图; 图3示出开机时读取中断向量值的流程图;以及图4示出执行中断服务程序的流程图。 1 shows a prior art basic computer rack illustrating FIG Ju; FIG. 2 shows a flowchart established indicator tables and the interrupt service routine; FIG. 3 shows a flow chart to read out the magnitude of the power interruption; 4 and FIG. a flow chart illustrating execution of the interrupt service routine. 具体实施方式依据本发明的可编程芯片软件防写保护的方法,以上述图1的电脑系统为例,图2示出建立指标表及中断服务程序的流程图。 DETAILED DESCRIPTION write-protected in accordance with the present invention the anti-software programmable chip method to the above-described computer system of FIG. 1 as an example, Figure 2 shows a flowchart of the establishment of index table and the interrupt service routine. 当一部电脑在出厂前, 首先,在电脑的基本输入输出系统(Basic Input Output System)撰写SMI(System Management Interrupt)服务程序(S24)以及其它系统设定程序,例如:逸定触发SMI的1/0地址,及读写可编程芯片指标的地址。 When a computer at the factory, first of all, in the computer's basic input output system (Basic Input Output System) Write SMI (System Management Interrupt) service routine (S24), and other system setup program, such as: Yi set to trigger an SMI 1 / 0 address and read address programmable chip index. 在中断向量 In the interrupt vector

表中适当的栏位放置一个中断向量值,这个中断向量值是对应于SMI服务程序的起始地址。 Table in the appropriate fields to place an interrupt vector value, the interrupt vector values ​​corresponding to the start address of the SMI service routine. 其次,在中断服务程序中建立指标表(S26),这个指标表中的指标资料是记录可编程芯片中不可任意修改的暂存器的地址值、中断向量的地址值、中断服务程序的地址值与此指标表的地址值。 Secondly, the interrupt service routine in the index table (S26), this indicator index data table address value is recorded in a programmable chip can not be arbitrarily modified register, the interrupt vector address value, the interrupt service routine address value value and address of this index table. 图3示出开机时读取中断向量值的流程图。 When the magnitude of the flow chart of FIG. 3 shows a read power interruption. 当电脑开机时,电脑从B10S 的只读存储器读取资料并执行程序,如系统的检查、将中断向量表载入存储器中及各芯片的设定等。 When the computer is turned on, the computer reads the data from the ROM and executes the program B10S, the inspection system, the interrupt load settings and various memory chip and a vector table. 此时,相对于SMI中断服务程序的中断向量值亦载入存储器中(S28)。 At this point, with respect to the SMI interrupt service routine interrupt vector values ​​are entered on the memory (S28). 举可编程芯片的組态暂存器为不可修改的暂存器为例,在系统中的可编程芯片的组态暂存器存入数值以设定各可编程芯片的功能,所以电脑开机完成各可编程芯片的功能设定后,各可編程芯片的組态暂存器所存入的数值是不可以任意修改的,故建立指标表以记录这些不可任意修改的可编程芯片的组态暂存器的地址,让CPU知道指标暂存器所指的地址是否为这些不可任意修改的可编程芯片的组态暂存器的地址。 For the configuration register programmable chip is an example unmodifiable register, the configuration register programmable chip in the system to set the value stored in the programmable functions of the chip, so the computer power on complete after each programmable chip function set, each programmable chip configuration register values ​​stored in the modification is not arbitrary, it is configured to establish the indicator table to record can not be arbitrarily modified programmable chips temporarily register address, so that CPU knows the address of index register within the meaning of the configuration registers whether any modifications of these non-programmable chip address. 当电脑升机完成系统的测试及设定后,电脑依使用者的需求执行所需的应用程序,依序完成所要的目的。 When the computer to perform the testing and set-liter system, the computer performs the required applications based on user demand, in turn accomplish the objectives desired. 若因人为的操作不当或病毒程序的侵入, 而发生修改可编程芯片的组态暂存器的数值,造成系统停滞或不稳定的情况,本发明所提出的方法是可以解決这个问题。 Ruoyin human improper operation or intrusion virus program, the value is modified configuration register programmable chips, or cause system instability stagnation, the method proposed in the present invention can solve this problem. 图4示出执行中断服务程序的流程图。 Figure 4 shows a flow chart of the interrupt service routine. 当CPU执行应用程序时,CPU 读取到写入可编程芯片的指标暂存器的指令,则CPU会中断目前的指令,然后在中断向量表找出一个中断向量值,这个中断向量值是对应于SMI服务程序的起始地址,接下来CPU升始执行SMI服务程序。 When the CPU executes the application program, the CPU reads the index register instructions written to the programmable chip, the CPU interrupts the current directive, then the interrupt vector table to find an interrupt vector value, this value corresponds to interrupt the starting address of the SMI service routine, followed by beginning to perform CPU-liter SMI service routine. 首先,CPU将目前的工作进度的资料储存起来(S30),接着,CPU判断指令中写入可编程芯片的指标暂存器的地址是否对应于指标表中的地址(S32),即判断写入指标暂存器所指的地址是否对应于可编程芯片的组态暂存器的地址,如果判断的结果为否,则取回工作进度的资料,离开SMI服务程序,继续执行未执行完毕的指令(S36);若结果为是,修改指令中的数值,修改后的数值使可编程芯片的指标暂存器所指的地址指向只读存储器的地址或者不影响系统正常运作的存储器的地址,不再是可編程芯片的组态暂存器的地址(S34)。 First, CPU of the information currently stored in progress (S30), Next, CPU determines whether the index register instruction to write a programmable chip address corresponding to the address index table (S32), i.e., determines the write address index register within the meaning corresponds to the programmable chip configuration register address, if the result of judgment is no, then retrieve information on the work progress, leaving the SMI service routine to continue executing instructions not finished the (S36); if the result is YES, the modified command value, so that the modified index value programmable chip address register points to the address indicated in the read-only memory or a memory address does not affect the normal operation of the system, not It is further configured programmable chip address register (S34). 当修改完毕后,取回工作进度的资料,离开SMI服务程序, 继续执行未执行完毕的指令(S36)。 When the modification is completed, information retrieval work schedule, leaving the SMI service routine to continue executing instructions not finished the (S36). 因此,本发明的优点系使用软件的方式来防止可編程芯片的組态暂存器 Thus, the advantages of the present invention using software-based manner to prevent the chip configuration register programmable

的数值被修改,只需增加一小段程序就可完成,不需增加额外的硬体线路, 如此,就不会增加硬体线路设计的复杂度。 The value is modified, the program can be completed only a small increase, without additional hardware lines, thus, does not increase the complexity of the hardware circuit design. 综上所述,虽然本发明已以优选实施例公开如上,然其并非用以限定本发明,任何本领域技术人员,在不脱离本发明的精神和茫围内,当可作各补的替代和修改,因此本发明的保护范围当由后附的杈利要求界定。 In summary, although the above disclosed embodiments of the present invention in a preferred, they are not intended to limit the present invention, anyone skilled in the art, without departing from the spirit of the present invention and the vast circumference, when the substitute can be made up of various and modified so that the scope of the present invention when executed by the appended claims benefit bifurcation defined.

Claims (4)

1.一种可编程芯片软件防写保护的方法,用于一电脑系统,该电脑系统包括一可编程芯片,该可编程芯片包括至少一指标暂存器,该方法包括步骤: 提供一中断服务程序及一指标表于该电脑系统中,该指标表包含该指标暂存器中的至少一禁止写入地址; 当CPU读取到一写入该可编程芯片的指标暂存器的指令时,执行该中断服务程序并且读入该指标表; 该中断服务程序判断该指令的写入指标暂存器的地址是否属于该指标表的该禁止写入地址; 当判断结果属于该禁止写入地址时,修改该指令所写入的该指标暂存器的地址为一不属于该禁止写入地址的替代地址;和根据该替代地址,执行该指令。 A programmable chip software write-protect method for a computer system, said computer system comprising a programmable chip, the chip including at least a programmable index register, the method comprising the steps of: providing an interrupt service and a program index table in the computer system, the index table containing the index register is prohibited in at least one write address; when a CPU read the index register instructions written in the programmable chip, and executing the interrupt service routine reads the index table; interrupt service routine determines the write pointer register the address of the instruction belongs to the address of the write-inhibit indicator table; when the determination result belongs to a write address when the prohibiting , modify the instruction written in the index register address is not a substitute address of the inhibit write address; and according to the alternative address, the instruction is executed.
2. 如杈利要求1所述的可編程芯片软件防写保护的方法,其中该中断服务程序及该地址表的步骤中,还包括设定一中断向量值,以作为该中断服务程序的起始地址。 2. The programmable chip bifurcation claims 1 prevention software write protection method, wherein the step of interrupt service routine address table and said, further comprising setting an interrupt vector value, as from the interrupt service routine start address.
3. 如杈利要求1所述的可編程芯片软件防写保护的方法,其中该指标表还包括一中断向量地址值、 一中断服务程序起始地址值与一指标表地址值。 The method according to the write-protect a software programmable chip 3. bifurcation claims, wherein the indicator further comprises an interrupt vector table address value, a start address of the interrupt service routine table address value and an index value.
4. 如杈利要求1所述的可編程芯片软件防写保护的方法,其中建立该指标表于该中断服务程序之中。 4. bifurcation claims programmable chip software write-protect method of claim 1, wherein in establishing the indicator table in the interrupt service routine.
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CN100474273C (en) 2006-04-28 2009-04-01 佛山市顺德区顺达电脑厂有限公司;神达电脑股份有限公司 Method and electronic device for preventing storing card from being written
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