1. A system-on-chip data security appliance (SoC-DSA) comprising: a single-chip device defining a protected boundary co-incident with a boundary of the single-chip device; a first communication interface; a second communication interface; an electronic processor located within the protected boundary; a cryptographic component located within the protected boundary; a data transfer control component located within the protection boundary; and memory located within the protected boundary, the memory storing data, wherein the electronic processor is configured to perform at least one of encrypting and decrypting data appearing on the first communication interface using the cryptographic component and subsequently perform, based on data stored in the memory, at least one of dropping, modifying, and transferring the data to the second communication interface using the data transfer control component.