CN102521385B - Method for setting forced access control on database system graph - Google Patents
Method for setting forced access control on database system graph Download PDFInfo
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- CN102521385B CN102521385B CN201110433709.7A CN201110433709A CN102521385B CN 102521385 B CN102521385 B CN 102521385B CN 201110433709 A CN201110433709 A CN 201110433709A CN 102521385 B CN102521385 B CN 102521385B
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Abstract
The invention discloses a method for setting forced access control on a database system graph, which includes steps: (1) judging whether an applied forced access control strategy exists and entering step (2) on yes judgment; (2) judging whether the database system graph of the applied forced access control strategy exists and entering step (3) on yes judgment; (3) judging whether a graph of the applied forced access control strategy is a system graph, entering step (4) on yes judgment and stopping the flow path on no judgment; and (4) judging whether the forced access control strategy is depended on repeatedly, namely whether the forced access control strategy is already applied to the system graph, building a dependence relation on no judgment and stopping the flow path on yes judgment. The method for setting forced access control on the database system graph can protect sensitive data in the database system graph.
Description
Technical field
The present invention relates to a kind of Access and control strategy of database method, particularly relate to a kind of method system table in database being arranged to forced symmetric centralization (Mandatory Access Control is called for short MAC), belong to technical field of database security.
Background technology
Database Systems carry the task of store and management business datum, and the security of guarantee and reinforcement Database Systems is importances for information security.The security of Database Systems depends on data base management system (DBMS) to a great extent.If the security mechanism of data base management system (DBMS) is as fairly perfect in access control policy etc., then the security performance of Database Systems is just relatively better.
The access control policy that conventional database systems provides can meet the requirement of general application, but cannot meet the demand of some important departments or Sensitive Domain.This is because in traditional database, general access control ability can only reach self contained navigation rank, manage according to unified mode for sensitive information and general information, authority by means of only user conducts interviews control, the effect of protection just cannot be reached for those premeditated saboteurs, particularly internal staff.In order to meet more and more higher safety requirements, needing the access control ability of Database Systems to bring up to forced symmetric centralization rank, providing special protection to sensitive data.
Forced symmetric centralization refers to that system is the security ensureing higher degree, the pressure access audit means taked according to the requirement of security strategy in TDI/TCSEC standard.In forced symmetric centralization, whole entities that data base management system (DBMS) (Database Management System is called for short DBMS) manages are divided into the large class of subject and object two.Main body comprises domestic consumer, system manager and superuser etc.; Object comprises database table, index, data dictionary and tuple etc. wherein.For subject and object, DBMS is that their each example assignment susceptibility marks (Label).Namely Mandatory Access Control is the Label by the Label and object comparing main body, finally determines whether main body can access object.
Be in the Chinese invention patent application of 201010578774.4 at application number, disclose a kind of database forced access control method based on strategy and system thereof.The method comprises the following steps: 1) for the tables of data in database set up multi-dimensional indexing tree; 2) the successively superposition of forced symmetric centralization safety label setting strategy is stored on the node of multi-dimensional indexing tree; 3) user access control is carried out based on having superposed tactful multi-dimensional indexing tree.This system comprises front-end and back-end, and front end comprises policy management component and index tree assembly, and rear end comprises access control components and strategy modification assembly.Use keeper of the present invention only need to manage a small amount of forced symmetric centralization safety label setting strategy in high-volume database, thus the expending of a large amount of minimizing time and manpower.Strategy is superimposed on index tree, the calculating of the safety label of data and the access control based on safety label can be combined as a whole with the retrieving of data, decreases extra retrieval consuming time.Improve the speed of response of execution efficiency and data access.
In conventional data base management system (DBMS) as in SQL Server, almost all configuration informations, safety information and object information are all stored in it self system table.System table is present in each independently database.While establishment database, data base management system (DBMS) can set up some system tables automatically, such as show SYSOBJECTS for the object graph, view, storing process etc. in descriptive data base, table SYSUSER is used for the user of descriptive data base, table SYSLOGINS is for preserving the login name of each server, password and configuration information, and table SYSDATABASE preserves all database names, the owner, state and other information etc. on server.For the user of Database Systems, no matter be the system table in direct usage data storehouse or the system table in indirect usage data storehouse, all need to prevent the object in system table from defining and used by undelegated user.Therefore, user, before operand (or data of object preservation), must have the right competence of access object definition.But, at present for the access control policy of Database System Tables, still there is no the technical solution of complete mature.
Summary of the invention
Technical matters to be solved by this invention is to provide a kind of method system table in database being arranged to forced symmetric centralization.
For realizing above-mentioned goal of the invention, the present invention adopts following technical scheme:
Database System Tables is arranged to a method for forced symmetric centralization, it is characterized in that comprising the steps:
(1) judge whether the Mandatory Access Control be employed exists, if Mandatory Access Control exists, enter step (2);
(2) judge whether the Database System Tables being employed Mandatory Access Control exists; If existed, enter step (3);
(3) judge whether the table being employed Mandatory Access Control is system table, if system table then enters step (4); If not system table, then process ends;
(4) judge whether Mandatory Access Control is repeated to rely on, and namely whether Mandatory Access Control has been applied on this system table, if be not applied on this system table, then can set up dependence; If Mandatory Access Control has been applied on system table, then process ends.
Wherein more preferably, said method also comprises the steps:
Judge that the system table setting up dependence is shared system table or unshared system table; if shared system table; then Mandatory Access Control and system table ID are write in the strategy on shared system table; if unshared system table, then this Mandatory Access Control is write in the strategy on protected system table.
Wherein more preferably, by the forced symmetric centralization information of Database Systems function setup Database System Tables, the forced symmetric centralization information of Database System Tables is recorded in the strategy of Database System Tables.
Wherein more preferably, the operation steps arranging the safety label of the row in correspondence system table comprises:
(11) judge to need the Mandatory Access Control deleted whether to exist, if existed, enter next step; If there is no, process ends;
(15) judge whether Mandatory Access Control is applied on goal systems table, if not application, then process ends; If applied, then go to next step;
(16) safety label based on row in correspondence system table is set.
Wherein more preferably, also comprise the steps: between step (11) and step (15)
(12) judge whether the system table being employed strategy is system table, judges whether this table exists simultaneously, if this table does not exist or be not system table, then process ends, otherwise enters next step.
Wherein more preferably, also comprise the steps: between step (12) and step (15)
(13) rational class information is judged whether, if yes then enter next step, if not then process ends.
Wherein more preferably, also comprise the steps: between step (13) and step (15)
(14) judge whether it is shared system table, for dissimilar system table, following flow process will transfer to different safe class tables.
Wherein more preferably, said method also comprises step Database System Tables being removed to Mandatory Access Control:
(21) judge whether the system table being employed strategy exists, if this table does not exist, then process ends; If this table exists, then enter next step;
(22) judge to need the Mandatory Access Control removed whether to exist, if there is no, then process ends; If existed, enter next step;
(24) check whether this Mandatory Access Control has produced with Database System Tables to rely on, if Mandatory Access Control is not applied on Database System Tables, this process ends; If produce dependence, then enter next step;
(25) remove the dependence of Database System Tables and Mandatory Access Control, also remove the label information in corresponding safe class simultaneously.
Wherein more preferably, also comprise the steps: between step (22) and step (24)
(23) judge that the Database System Tables be cited is the system table of what type, if shared system table, then the operand of following flow process is the strategy on shared system table, if unshared system table, then the operand of following flow process is the strategy on protected system table; Then next step is entered.
Forced access control method provided by the present invention can arrange Mandatory Access Control to Database System Tables.When user accesses data storehouse system table; first the forced symmetric centralization authority of Database System Tables is checked; uncommitted non-authority user can not access this system table, only has authorized authority user can access this system table, thus protects the sensitive data in system table.
Accompanying drawing explanation
Below in conjunction with the drawings and specific embodiments, the present invention is described in further detail.
Fig. 1 is schematic diagram Database System Tables being arranged to Mandatory Access Control;
Fig. 2 is the operation steps schematic diagram to Database System Tables application Mandatory Access Control;
Fig. 3 is operation steps schematic diagram Database System Tables being removed to Mandatory Access Control;
Fig. 4 is the operation steps schematic diagram of the safety label of the row arranged in correspondence system table.
Embodiment
Basic ideas of the present invention are to arrange the forced symmetric centralization authority to Database System Tables, prevent the object in Database System Tables from defining and are used by undelegated user.Forced symmetric centralization authority herein refers to authorizing and retrieving to control the access to information by authority (SELECT, INSERT, UPDATE and DELETE).
As shown in Figure 1, the present invention arranges forced symmetric centralization (MAC) strategy in the system table of Database Systems, namely the access control right of interface to Database System Tables that security official is provided by calling data storehouse system is arranged, and policy information is left in Database System Tables, make Database System Tables have corresponding forced symmetric centralization authority.When user accesses data storehouse system table; first the forced symmetric centralization authority of Database System Tables is checked; uncommitted non-authority user can not access this system table, only has authorized authority user can access this system table, thus protects the sensitive data in system table.
In the present invention, the system table of database comprises shared (shared) system table and unshared system table.They all save the metamessage that database is shared.Said system table Mandatory Access Control all carries out same control to shared system table and unshared system table.
In order to the Mandatory Access Control of storage system table, first need the Database System Tables that increase by four is new.Deposit respectively:
strategy (see table 1:SYS_ forced symmetric centralization _ SHCATALOG_ENFORCEMENT) on shared system table, this table is shared system table.
| Row | Type | Describe |
| POLICYID | OID | Strategy OID |
| RELOID | OID | Table OID (must be system table) |
Table 1SYS_ forced symmetric centralization _ SHCATALOG_ENFORCEMENT
the each row safe class of shared system table (see table 2:SYS_ forced symmetric centralization _ SHCATALOG_ROW_LABEL), this table is shared system table.
| Row | Type | Describe |
| POLICYID | OID | Strategy OID |
| RELOID | OID | Table OID (must be system table) |
Table 2SYS_ forced symmetric centralization _ CATALOG_ENFORCEMENT
strategy (see table 3:SYS_ forced symmetric centralization _ SHCATALOG_ENFORCEMENT) on protected system table, this table is non-shared system table.
Table 3SYS_ forced symmetric centralization _ CATALOG_ROW_LABEL
the safe class (see table 4:SYS_ forced symmetric centralization _ CATALOG_ROW_LABEL) of each row in protected system, this table is non-shared system table.
Table 4SYS_ forced symmetric centralization _ SHCATALOG_ROW_LABEL
The interface that above-mentioned Database Systems provide is Database Systems function, by the forced symmetric centralization information of Database Systems function setup Database System Tables.Specifically, by increasing system function APPLY_SYS_CATALOG_POLICY, the forced symmetric centralization information of Database System Tables being recorded in the strategy (SYS_ forced symmetric centralization _ SHCATALOG_ENFORCEMENT) of Database System Tables, cancelling the forced symmetric centralization to Database System Tables by system function REMOVE_SYS_CATALOG_POLICY.
Fig. 2 shows the operation steps to Database System Tables application Mandatory Access Control.This step specifically comprises:
(1) judge whether the Mandatory Access Control be employed exists, if Mandatory Access Control exists, enter step 2;
(2) judge whether the Database System Tables being employed Mandatory Access Control exists; If existed, enter step 3;
(3) judge whether the table being employed Mandatory Access Control is system table, if system table then enters step 4; If not system table, not by the method application Mandatory Access Control, process ends;
(4) judge whether Mandatory Access Control is repeated to rely on, and namely whether Mandatory Access Control has been applied on this system table, if be not applied on this system table, then can set up dependence, enter step 5; If Mandatory Access Control has been applied on system table, can not repeat to set up dependence, then process ends;
(5) judge that the system table setting up dependence is shared system table or unshared system table; if shared system table; then Mandatory Access Control and system table ID are write in the strategy (SYS_ forced symmetric centralization _ SHCATALOG_ENFORCEMENT) on shared system table; if unshared system table, then this Mandatory Access Control is write in the strategy (SYS_ forced symmetric centralization _ SHCATALOG_ENFORCEMENT) on protected system table.
Fig. 3 shows operation steps Database System Tables being removed to Mandatory Access Control.This step specifically comprises:
(1) judge be cited strategy system table whether exist, if this table does not exist, then can not continue perform flow process, produce false alarm;
(2) whether judge to need the Mandatory Access Control removed to exist, if there is no, be then illegal operation;
(3) judge that the Database System Tables be cited is the system table of what type, if shared system table, then the operand of following execution flow process is the strategy (SYS_ forced symmetric centralization _ SHCATALOG_ENFORCEMENT) on shared system table, if unshared system table, then the operand of following execution flow process is the strategy (SYS_ forced symmetric centralization _ SHCATALOG_ENFORCEMENT) on protected system table;
(4) check whether this Mandatory Access Control has produced with Database System Tables to rely on, namely Mandatory Access Control has been applied on Database System Tables, if Mandatory Access Control is not applied on Database System Tables, this is operating as illegal operation.
(5) whether judge mark can be eliminated, if can be eliminated and meet above condition, then remove the dependence of Database System Tables and Mandatory Access Control, also remove label (mark) information in corresponding safe class simultaneously; If can not be eliminated, directly terminate.
Applying Database System Tables or removing in the process of Mandatory Access Control, need the safety label of the row arranged in correspondence system table.Now, owing to have employed the security management mechanism (can be specifically the Chinese invention patent application of 200610019230.8 see application number) of separation of the three powers, user does not modify to Database System Tables by UPDATE statement.Therefore, for the row in the Database System Tables existed, the mark of function SET_SYS_CATALOG_ROW_LABEL to row can be used to adjust accordingly, and update strategy (SYS_ forced symmetric centralization _ SHCATALOG_ROW_LABEL or SYS_ forced symmetric centralization _ CATALOG_ROW_LABEL), corresponding safety label is set.
Fig. 4 shows the operation steps of the safety label of the row arranged in correspondence system table.This step specifically comprises:
(1) whether judge to need the Mandatory Access Control deleted to exist, if there is no, be then illegal operation;
(2) judge to be cited the system table whether system table of strategy, judges whether this table exists simultaneously, if this table does not exist or be not system table, then can not continue to perform flow process, produce false alarm;
(3) rational class information is judged whether;
(4) judge whether it is shared system table, for dissimilar system table, following flow process will transfer to different safe class tables;
(5) judge whether Mandatory Access Control is applied on goal systems table, if not application, then end operation, if applied, then goes to step (6);
(6) safety label based on row in correspondence system table is set.
After Mandatory Access Control is applied to Database System Tables, when user is conducted interviews to Database System Tables by common SQL query, RTE (RTU (remote terminal unit)) in traversal queries request, replaces (query rewrite) by the RTE inquiry wherein about Database System Tables and becomes the connection (JOIN) of Database System Tables and Mandatory Access Control system table to inquire about.
Database Systems, in operational process, need to carry out dereference to Database System Tables to complete specific query function, obtain object definition.For dissimilar SQL statement, carry out the inspection based on Mandatory Access Control in its porch.User, when direct accessing database system table, checks the forced symmetric centralization authority of Database System Tables, only to the open authority of authorized user.User is when accessing certain Database System Tables, and these operations can other Database System Tables of dereference, therefore also needs the forced symmetric centralization authority of the Database System Tables checking other, only to the open authority of authorized user.
Specifically, the read right of the Mandatory Access Control of Database System Tables not control system table definition, only controls the access limit of subscriber's meter definition.User needs to write Database System Tables when creating object, preserves active user institute and creates the definition of object, is equivalent to perform INSERT (insertion) to Database System Tables and operates.At this moment the record for inserting generates legal safety label.This safety label comes from the row labels of active user, but does not check whether user has read right to system table definition.User is while to certain object executable operations, in fact SELECT (selection) operation can indirectly be carried out to the definition of Database System Tables, now need user to have read right to object definition, but need not read right be had on the Database Systems table definition of correspondence.During to object modification, deletion (write object definition, be equivalent to perform UPDATE/DELETE operation to system table), without the need for the read right of object definition, but need the write permission of object.
To provided by the present invention, the method that Database System Tables arranges forced symmetric centralization is described in detail above.To those skilled in the art, to any apparent change that it does under the prerequisite not deviating from connotation of the present invention, all by formation to infringement of patent right of the present invention, corresponding legal liabilities will be born.
Claims (8)
1. Database System Tables is arranged to a method for forced symmetric centralization, it is characterized in that comprising the steps:
(1) judge whether the Mandatory Access Control be employed exists, if Mandatory Access Control exists, enter step (2);
(2) judge whether the Database System Tables being employed Mandatory Access Control exists; If existed, enter step (3);
(3) judge whether the table being employed Mandatory Access Control is system table, if system table then enters step (4); If not system table, then process ends;
(4) judge whether Mandatory Access Control is repeated to rely on, namely whether Mandatory Access Control has been applied on this system table, if be not applied on this system table, then set up dependence, be described system table and forced symmetric centralization authority is set; If Mandatory Access Control has been applied on system table, then process ends;
(5) judge that the system table arranging forced symmetric centralization authority is shared system table or unshared system table, when setting up forced symmetric centralization authority, if shared system table, then Mandatory Access Control and system table ID are write in the strategy on shared system table, if unshared system table, then this Mandatory Access Control is write in the strategy on protected system table; When removing forced symmetric centralization authority, if shared system table, then the operand of follow-up flow process is the strategy on shared system table, if unshared system table, then the operand of follow-up flow process is the strategy on protected system table;
Wherein, the read right of described Mandatory Access Control not control system table definition, only controls the access limit of subscriber's meter definition.
2. method Database System Tables being arranged to forced symmetric centralization as claimed in claim 1, is characterized in that,
By the forced symmetric centralization information of Database Systems function setup Database System Tables, the forced symmetric centralization information of Database System Tables is recorded in the strategy of Database System Tables.
3. method Database System Tables being arranged to forced symmetric centralization as claimed in claim 1, characterized by further comprising the operation steps of the safety label of the row arranged in correspondence system table.
4. method Database System Tables being arranged to forced symmetric centralization as claimed in claim 3, it is characterized in that, the operation steps of the safety label of the described row arranged in correspondence system table comprises:
(11) judge to need the Mandatory Access Control deleted whether to exist, if existed, enter next step; If there is no, process ends;
(15) judge whether Mandatory Access Control is applied on goal systems table, if not application, then process ends; If applied, then go to next step;
(16) safety label based on row in correspondence system table is set.
5. method Database System Tables being arranged to forced symmetric centralization as claimed in claim 4, is characterized in that also comprising the steps: between step (11) and step (15)
(12) judge whether the system table being employed strategy is system table, judges whether this table exists simultaneously, if this table does not exist or be not system table, then process ends, otherwise enters next step.
6. method Database System Tables being arranged to forced symmetric centralization as claimed in claim 5, is characterized in that also comprising the steps: between step (12) and step (15)
(13) rational class information is judged whether, if yes then enter next step, if not then process ends.
7. method Database System Tables being arranged to forced symmetric centralization as claimed in claim 6, is characterized in that also comprising the steps: between step (13) and step (15)
(14) judge whether it is shared system table, for dissimilar system table, follow-up flow process will transfer to different safe class tables.
8. method Database System Tables being arranged to forced symmetric centralization as claimed in claim 1, is characterized in that step Database System Tables being removed to Mandatory Access Control comprises:
(21) judge whether the system table being employed strategy exists, if this table does not exist, then process ends; If this table exists, then enter next step;
(22) judge to need the Mandatory Access Control removed whether to exist, if there is no, then process ends; If existed, enter next step;
(23) check whether this Mandatory Access Control has produced with Database System Tables to rely on, if Mandatory Access Control is not applied on Database System Tables, this process ends; If produce dependence, then enter next step;
(24) remove the dependence of Database System Tables and Mandatory Access Control, also remove the label information in corresponding safe class simultaneously.
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| CN105512569A (en) * | 2015-12-17 | 2016-04-20 | 浪潮电子信息产业股份有限公司 | Database security reinforcing method and device |
| CN106293875A (en) * | 2016-08-04 | 2017-01-04 | 中国联合网络通信集团有限公司 | The creation method of a kind of Docker container and the system of establishment |
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| CN112613075A (en) * | 2020-12-31 | 2021-04-06 | 北京安华金和科技有限公司 | Permission determination method and device, storage medium and electronic device |
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