COMPRESS

This repository contains the tool COMPRESS described in the paper "Compress: Reducing Area and Latency of Masked Pipelined Circuits"

Canonical location: https://github.com/cassiersg/compress.

Dependencies

COMPRESS itself is a python3 script (tested with python3.10), with dependencies given in requirements.txt.

Other parts of the flow use iverilog (tested with version 0.11) and yosys (tested with version 0.33) respectively for simulation and area usage estimation of the netlist generated by COMPRESS.

Usage

Example:

make CIRCUIT=circuits/bp_sbox.txt "LATS=4 5" "DS=2 3" area -j

produces area results for the Boyar-Peralta AES S-box (circuits/aes_bp.txt) with 2 and 3 shares, latency 4 and 5 in work/aes_bp_area.csv.

Variables for make invocation:

• WORK: directory where all intermediate files are stored
• CIRCUIT: path to a circuit file (e.g., circuits/bp_sbox.txt)
• LATS: space-separated list of latencies (a circuit is generated for each latency)
• DS: space-separated number of shares (a circuit is generated for each number of shares)
• GADGETS_CONFIG: list of gadgets that can be used for synthesis (default: gadget_library/all_gadgets.toml)

In order to only run the COMPRESS design generation, use directly scripts/compress.py (run python3 scripts/compress.py --help for command-line parameters).

Adder generation

The script scripts/generate_adder_circuit.py has been used to generate the adder circuits in circuits/.

Usage:

python3 scripts/generate_adder_circuit.py -n <bit_width> --type <TYPE> --out <OUTPATH>

where

• -n <bit_width> refers to the input bits of the summands
• --out indicates the generated file path
• --type refers to the adder type. The following adders are currently supported:
  • RC1: standard ripple-carry adder computing the carry as c_(i+1) = (a_i & b_i) ^ (b_i & c_i) ^ (a_i & c_i)
  • RC2: slightly improved ripple-carry adder computing the carry as c_(i+1) = (a_i & b_i) ^ ((a_i ^ b_i) & c_i)
  • RC3: more improved ripple-carry adder computing the carry as c_(i+1) = a_i ^ ( (a_i ^ b_i) & (a_i ^ c_(i-1) ))
  • KS: Koggle-Stone adder as described in https://www.mdpi.com/2076-3417/12/5/2274
  • sklansky: Sklansky adder as described in https://www.mdpi.com/2076-3417/12/5/2274
  • BK: Brent-Kung adder as described in https://www.mdpi.com/2076-3417/12/5/2274

Contents

Selected files/directories:

├── circuits # textual description of some circuits to mask
├── gadget_library
│   ├── BIN/bin_REG.v # simple reg, instantiated in masked gadgets
│   ├── *.toml # sets of gadgets with metadata.
│   ├── MSK
│   │   └── *.v, *.vh # implementation of the gadgets
│   └── RNG # PRNG based on Trivum for generating masking randomness.
├── Makefile # Top-level entry point.
├── scripts # python scripts: COMPRESS, its dependencies, pre- and post-processing.
├── simu.mk # behavioral and structural simulation of circuits generated by COMPRESS.
└── synthesis # synthesis with Yosys and Nangate45

License

GPLv3 and CERN-OHL-S v2, see LICENSE.txt