Abstract: System and method is disclosed for protecting client software running on a client computer from tampering using a secure server. Prior to or independent of executing the client software, the system integrates self-protection into the client software; removes functions from the client software for execution on the server; develops client software self-protection updates; and periodically distributes the updates. During execution of the client software, the system receives an initial request from the client computer for execution of the removed function; verifies the initial request; and cooperates with the client computer in execution of the client software if verification is successful. If verification is unsuccessful, the system can attempt to update the client software on the client computer; and require a new initial request. Client software can be updated on occurrence of a triggering event. Communications can be encrypted, and the encryption updated. Authenticating checksums can be used for verification.

Abstract: An anti-tamper system is disclosed that includes self-adjusting guards inserted in software. Self-adjusting guards include invocation criteria and guard function. During run-time, each time the self-adjusting guard is invoked, the invocation criteria is evaluated and the guard function is only executed if the invocation criteria is satisfied. The invocation criteria can be static or dynamic, satisfied randomly with fixed or varying probability, a monotonically or exponentially decreasing function or most any other type of function. The invocation criteria can be satisfied based on elapsed inter-guard invocation time (time since last guard function execution), target inter-guard invocation time, and/or guard execution time. A method is disclosed of inserting self-adjusting guards into software, and executing the software. Evaluating the invocation criteria can include adjusting the invocation criteria when satisfied. The self-adjusting guards can be inserted into the software at a source or object code level.

Abstract: A system and method for protecting a software program from unauthorized modification or exploitation. A software security mechanism according to the present invention is difficult for a hacker or cracker to detect and/or defeat, but does not impose excessive runtime overhead on the host software program. The present invention further comprises a system and method for automating the injection of a software security mechanism according to the present invention into a host software program.