CIRCUITRY AND METHODS FOR CRYPTOGRAPHICALLY ENFORCING CONTROL-FLOW INTEGRITY

Techniques for cryptographically enforcing control-flow integrity are described. In certain examples, a processor includes: a cryptographic circuit to encrypt, with a first key, a first code section to be stored in a single page of memory, and to encrypt, with a second key, a second code section to be stored in the single page of memory; decoder circuitry to decode a single instruction into a decoded single instruction, the single instruction comprising a key identifier, an identifier of the second code section, and an opcode that is to indicate execution circuitry is to, when executing the first code section, determine if the key identifier corresponds to the second key, and in response to corresponding, cause the cryptographic circuit to switch to using the second key to decrypt the second code section, and transfer execution from the first code section to the second code section; and the execution circuitry to execute the decoded instruction according to the opcode.