CN112685779A - Static credibility judgment method for executing main keywords of select statement based on database - Google Patents

Abstract

The invention provides a static credibility judgment method for executing main keywords of select statement based on a database, which comprises the following steps: s1, determining main keywords according to the characteristics of an SQL statement by an administrator, calculating a hash value of a keyword character string, adding the hash to the original latest PCR, and performing hash calculation to obtain a new PCR value; s2, when the database runs in a trusted environment, a user uses a select statement to inquire and calculates a PCR value of the select statement; s3, comparing the PCR value obtained in the step S2 with the PCR value obtained in the step S1; and S4, the comparison result proves that the SQL sentence input by the current user is credible consistently, the next operation is continuously executed, the inconsistency proves that the user operation is not credible, and the execution is terminated and fed back to the user. The main keywords selected by the static credibility judgment method for executing the main keywords of the select statement based on the database are the keywords used by the user executing most of the select statements, and the static credibility calculation can meet the user requirements as much as possible.

Description

Static credibility judgment method for executing main keywords of select statement based on database

Technical Field

The invention belongs to the technical field of databases, and particularly relates to a static credibility judgment method for executing main keywords of a select statement based on a database.

Background

With the rapid development of information technology, the data security problem is becoming more complex, and the trusted computing technology is also developing continuously as an important means for protecting data security. Today, trusted computing is used in a number of ways, such as identity theft protection, digital rights management, and the like. In order to solve the insecurity of a computer and a network structure and improve the safety fundamentally, a trusted hardware environment is started based on a trusted root of a trusted control module (TPMC) to measure the reliability of an operating system, a trust relationship is expanded to the operating system environment, the reliability of application and the network is measured to form a trusted safe operating environment guaranteed by a trusted chain, and the trusted measurement is carried out when a database is installed, so that the environment credibility and the static credibility of the database are realized, but the further credibility measurement of dynamic information of the database is lacked. The user performs credibility measurement on the operation of increasing, deleting, modifying and checking the data information in the database through SQL to know whether the user behavior is credible or not, which is very important for protecting the data security of the database. Meanwhile, the SQL statement has a plurality of keywords, various keywords can form various combinations, each combination is used as one group for carrying out credibility measurement, and a large amount of storage space and credibility measurement time are wasted.

Disclosure of Invention

In view of the above, in order to overcome the above drawbacks, the present invention is directed to a static confidence determination method for executing a main keyword of a select statement based on a database.

In order to achieve the purpose, the technical scheme of the invention is realized as follows:

a static credibility judgment method for executing main keywords of select statement based on a database comprises the following steps:

s1, determining main keywords according to the characteristics of an SQL statement by an administrator, calculating a hash value of a keyword character string, adding the hash to the original latest PCR, and performing hash calculation to obtain a new PCR value;

s2, when the database runs in a trusted environment, a user uses a select statement to inquire and calculates a PCR value of the select statement;

s3, comparing the PCR value obtained in the step S2 with the PCR value obtained in the step S1;

and S4, the comparison result proves that the SQL sentence input by the current user is credible consistently, the next operation is continuously executed, the inconsistency proves that the user operation is not credible, and the execution is terminated and fed back to the user.

Further, in step S1, the new PCR value is stored in the register of the TCG, so that the query statement input by the user can be compared with the confidence measure.

Further, the method for calculating the PCR value of the select statement in step S2 is as follows:

and analyzing the SQL statement by a syntax analyzer and a compiler to generate a syntax analysis tree, extracting main keywords in the query statement and combining the main keywords into a character string, performing hash operation to obtain a summary value, combining the summary value with the last PCR value in the credible chain, and performing the hash operation again to obtain the PCR value of the select statement.

Compared with the prior art, the static credibility judgment method for executing the main keywords of the select statement based on the database has the following advantages:

the static credibility judgment method for executing the main keywords of the select statement based on the database has the following advantages that: firstly, the selected main keywords are the keywords used by the user to execute most select sentences, and the keywords are used for performing static trusted calculation so as to meet the requirements of the user as much as possible; in addition, the main keywords are subjected to static credible calculation, PCR values of the main keywords are stored in the TCG, the number of traversals is small, and the judgment efficiency is high.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate an embodiment of the invention and, together with the description, serve to explain the invention and not to limit the invention. In the drawings:

FIG. 1 is an overall flow diagram;

FIG. 2 is a schematic diagram of a parse tree;

FIG. 3 is an example view of a parse tree;

FIG. 4 is an example parse tree diagram of FIG. two.

Detailed Description

It should be noted that the embodiments and features of the embodiments may be combined with each other without conflict.

In the description of the present invention, it is to be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like, indicate orientations or positional relationships based on those shown in the drawings, and are used only for convenience in describing the present invention and for simplicity in description, and do not indicate or imply that the referenced devices or elements must have a particular orientation, be constructed and operated in a particular orientation, and thus, are not to be construed as limiting the present invention. Furthermore, the terms "first", "second", etc. are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first," "second," etc. may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless otherwise specified.

In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present invention can be understood by those of ordinary skill in the art through specific situations.

The present invention will be described in detail below with reference to the embodiments with reference to the attached drawings.

As shown in fig. 1 and fig. 2, a static credibility judgment method for executing a main keyword of a select statement based on a database includes the following steps:

s1, determining main keywords according to the characteristics of an SQL statement by an administrator, calculating a hash value of a keyword character string, adding the hash to the original latest PCR, and performing hash calculation to obtain a new PCR value;

s2, when the database runs in a trusted environment, a user uses a select statement to inquire and calculates a PCR value of the select statement;

s3, comparing the PCR value obtained in the step S2 with the PCR value obtained in the step S1;

and S4, the comparison result proves that the SQL sentence input by the current user is credible consistently, the next operation is continuously executed, the inconsistency proves that the user operation is not credible, and the execution is terminated and fed back to the user.

In step S1, the new PCR value is stored in the register of the TCG for comparing the query statement input by the user with the confidence metric.

The method for calculating the PCR value of the select statement in step S2 is as follows:

and analyzing the SQL statement by a syntax analyzer and a compiler to generate a syntax analysis tree, extracting main keywords in the query statement and combining the main keywords into a character string, performing hash operation to obtain a summary value, combining the summary value with the last PCR value in the credible chain, and performing the hash operation again to obtain the PCR value of the select statement.

According to the method, an administrator sets credible keywords, after the keywords are combined into a character string, the abstract of the character string is calculated by using a hash algorithm, a new PCR value corresponding to an SQL statement is calculated by combining with a PCR and stored in a register of a TCG, and a credible chain is expanded to compare the credible measurement of the query statement input by a user.

The user enters a query statement. The parser examines the syntax of the user query and then constructs a parse tree representation of the query statement. And extracting and combining the main keywords into a character string, and calculating the character string by using a hash algorithm to obtain a hash value.

And combining the hash result of the main key words of the statement input by the user with the latest credible PCR in the TCG to calculate a hash value to obtain a new undetermined PCR value.

And comparing the undetermined PCR value with a preset PCR value in a corresponding keyword register of the TCG, if the two PCR values are different, proving that the operation of the user is not credible, and prompting an error to the user and refusing to access the database. If the two PCR values are the same, the user operation is proved to be credible, and the next operation is continuously executed.

The technical scheme of the application is further explained by combining the specific examples as follows:

s1: the security administrator of the system sets a comparison template in the trusted database. The administrator makes the following statement settings

“user1；

8:00AM～16:00PM；

Select...from...where...”

The keywords select.. from.. where.. are merged into a string, hashing is performed using SM3 algorithm to obtain a digest 0xB3F7 …, which is added to the PCR value of the crude oil to calculate a new digest value 0xC236 …, which is stored in the memory of the TCG.

S2: and the user uses a select statement to inquire, generates a syntax analysis tree through a syntax analyzer and a translator, extracts and combines the keywords of the query statement into a character string and carries out hash operation.

And (3) during normal query: select from tb1 where name is zhang san;

the resulting parse tree is shown in fig. 3.

The keywords' select.

When the operation is not credible: delete from. The parse tree for this SQL statement is shown in FIG. 4.

Extracting keywords' delete from.

And S3, comparing the PCR to be determined in S2 with the PCR value in the corresponding register of S1. And if the PCR value of the normal query is the same as the preset PCR value in the register, the comparison is successful, and the database returns a statement of 'allowing access' and simultaneously returns a query result. The hash value of the key word of the untrusted SQL statement is changed, the computed PCR value is different from the PCR value stored in the register in the S1, the comparison is unsuccessful, the database returns a statement of 'access refusal', and a user cannot use the statement to query the statement, and the user needs to modify the statement to query again.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.

Claims (3)

1. The static credibility judgment method for executing the main keywords of the select statement based on the database is characterized by comprising the following steps of:

s1, determining main keywords according to the characteristics of an SQL statement by an administrator, calculating a hash value of a keyword character string, adding the hash to the original latest PCR, and performing hash calculation to obtain a new PCR value;

s2, when the database runs in a trusted environment, a user uses a select statement to inquire and calculates a PCR value of the select statement;

s3, comparing the PCR value obtained in the step S2 with the PCR value obtained in the step S1;

and S4, the comparison result proves that the SQL sentence input by the current user is credible consistently, the next operation is continuously executed, the inconsistency proves that the user operation is not credible, and the execution is terminated and fed back to the user.

2. The static credible judgment method for executing select statement primary keywords based on database according to claim 1, wherein: in step S1, the new PCR value is stored in the register of the TCG for comparing the query statement input by the user with the confidence metric.

3. The static credibility determination method for executing select statement main keyword based on database according to claim 1, wherein the method for calculating PCR value of select statement in step S2 is as follows:

and analyzing the SQL statement by a syntax analyzer and a compiler to generate a syntax analysis tree, extracting main keywords in the query statement and combining the main keywords into a character string, performing hash operation to obtain a summary value, combining the summary value with the last PCR value in the credible chain, and performing the hash operation again to obtain the PCR value of the select statement.

Images