Report on the Design and Implementation of a Garbled Processor Architecture Supporting Trade-off between Privacy and Performance
In this report, we present GarbledCPU, the first framework that realizes a hardware-based general purpose sequential processor for secure computation. Our MIPS-based implementation enables development of applications (functions) in a high-level language while performing secure function evaluation (SFE) using Yao's garbled circuit protocol in hardware. GarbledCPU provides three degrees of freedom for SFE which allow leveraging the trade-off between privacy and performance: public functions, private functions, and semi-private functions. We synthesize GarbledCPU on a Virtex-7 FPGA as a proof-of-concept implementation and evaluate it on various benchmarks including Hamming distance, private set intersection and AES. Our results indicate that our pipelined hardware framework outperforms the fastest available software implementation.