MQP:Security Analysis Data Model

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Overview

In order to provide the results of analysis, a data structure was devised to store the results.

Requirements

• The structure should be easy to search and traverse
• The structure must contain a representation of each code element analyzed along with the permissions required by each code element
• Each permission requirement must provide a complete path to where the requirement originated
• Each permission requirement must provide the names of the methods that determined it
• The structure must hold "Management Data" - policy information that comes from absolute sources (for example, the security policy of a given server or user input at runtime)
• There must be a way to calculate the resultant set of policy
• There should be a way to optimize the resultant set of policy by analyzing overlapping permission requirements

Design

• Data storage
  • A top level singleton class, AnalysisModel, contains each CodeBlock
    • CodeBlock - Any grouping of code: package, protection domain, class, method, etc.
    • The CodeBlock contains any number of PermissionRequirements and any number of PolicyDescriptions
      • PermissionRequirement - Tells what permission is required (using a PermissionDescription), the path to get to the permission checking call, and a list of tools that agree on this requirement
      • PolicyDescription - Describes a set of policy
• Data Retrieval
  • Search is performed from the AnalysisModel - any CodeBlock can be found this way, as the AnaysisModel contains each CodeBlock
  • Traversal of the call structure is performed from any CodeBlock - each has a list of children and a reference back to its parent (if any)
  • Traversal of the permission structure is performed from any PermissionRequirement (via a CodeBlock) - each PermissionRequirement has a full trace to the origin of the permission it describes
  • Resultant policy calculation uses a PolicyApplicationStrategy, which starts at any CodeBlock, and is passed through all its children, processing permissions as it goes
  • Policy optimization can occur if more than one PermissionRequirement exists for a given PermissionDescription

Security Analysis Model