Recent data breaches have motivated a desire to remove all trust storage platforms (e.g., the cloud). To this end, research has focused on implementing cryptographic access controls on untrusted storage platforms. However, there are issues with the feasibility of implementing such controls, particularly when revocation (i.e., a user losing permission) occurs. This thesis investigates the opportunity to increase the viability of these systems by exploiting new functionality in emerging main memory technology. Technology such as the Hybrid Memory Cube possess the ability to perform certain computations in-memory, without reading data into the CPU. This thesis focuses on implementing a re-encryption scheme, called keystream re-encryption, that computes a stream of key material that can be XOR-ed in-memory to re-encrypt a file, without ever bringing the contents of that file into the CPU. We show that keystream re-encryption can produce 5-10% improvements in Instructions Per Cycle (IPC), while also increasing throughput by 18% and reducing energy consumption by 44-65%
