Bridge between instrumentation and IAST

[manuel-alvarez-alvarez]

What Does This Do

Introduces a bridge class between instrumentations and an IAST module. All hooks in IAST instrumentation will call static methods of this bridge.

Motivation

Due to the potentially large amount of callbacks the IAST module will receive and performance requirements for certain operations, we have decided to introduce a custom bridge for direct communication between instrumentations and IAST. This bridge will have static methods for each of the callbacks that the IAST will be installing. Static methods are selected mostly because they need simpler instrumentation, with less stack operations and better performance. The callbacks will be added to client code by instrumentation modules. The callback implementations will be in the dd-java-agent/iast module.

Additional Notes

IASTModule will be implemented in future pull requests.