Anonymizing sensitive data in logic problems for input to a constraint solver

Abstract

A document anonymization system transforms structured documents, such as security policies, that contain user-specific and other sensitive data, producing encoded logic problems in the format or language of one or more constraint solvers; the logic problems do not contain any of the sensitive data. The system may perform a one- or two-stage anonymization process: in a first stage, the electronic document is analyzed according to its document type to identify parameters likely to contain sensitive data, and the associated values are replaced with arbitrary values; in a second stage, after the anonymized electronic document is converted into logic formulae representing the data, the system performs replacements of string constants in the logic formulae with arbitrary strings to further anonymize the sensitive data. The system may confirm that anonymization preserves the document structure, difficulty level, and satisfiability of the original document by executing the constraint solver against the anonymized logic problem.