Eurus - Precise Attack Synthesis for DeFi Apps

Eurus is an open-source general framework for smart contract verification and synthesis. Eurus performs reasoning using a builtin symbolic virtual machine based on the YUL intermediate language from Solidity.

Eurus is still under active development. Please see different branches for history versions (e.g. demo version).

Building from Docker

docker build -t eurus:v0 .
docker run -it --rm eurus:v0 bash

Building from Source

• Python (3.6+, Anaconda3 is highly recommended; otherwise you may be missing some packages)

  • Set alias of python in your environment to python3
  • pysha3: https://github.com/tiran/pysha3
    • pip install pysha3==1.0.2
    • This is temporarily required for supporting keccak-256 hashing/computation.
  • eth-abi: https://github.com/ethereum/eth-abi
    • pip install eth_abi==2.1.1
    • This is for easy abi encoding.

• Racket (8.0+): https://racket-lang.org/

  • Rosette (4.0+): https://github.com/emina/rosette
    • raco pkg install rosette
  • bv package (for running racket version of interpreter): https://github.com/pmatos/racket-bv
    • raco pkg install bv
  • sha package
    • raco pkg install sha

• Solidity/Solc (0.8.14+ required; older versions have known Yul support issues): https://soliditylang.org/

  • solc-select is recommended: https://github.com/crytic/solc-select

• Antlr (4.8 required, not compatible with other versions): https://github.com/antlr/antlr4

  • Python Targets Setup: https://github.com/antlr/antlr4/blob/master/doc/python-target.md
  • pip install antlr4-python3-runtime==4.8
  • You also need antlr backend, for Ubuntu, run sudo apt-get install antlr4; for other systems, please check the Antlr homepage: https://www.antlr.org/

Python Yul Parser

This parses the Yul source code into json representation, and generates a helper configuration file which includes:

• mapping of call codes and function names (signatures)

usage: yul_parser.py [-h] [--yul YUL] [--verbose VERBOSE]
optional arguments:
-h, --help show this help message and exit
--yul YUL input yul file
--verbose VERBOSE show more info for debugging

It will automatically outputs filename.json and filename.config.json in the same folder.

Example Usage

There are two sets of examples in examples/ showing how to use Eurus to perform concrete and symbolic execution with verification performed. The ex/ corresponds to the concrete reasoning part of Eurus, and the symex/ corresponds to the symbolic reasoning part. To run them, you'll need to first prepare them by running:

cd examples/
bash ./prepare-ex.sh
# or:# bash ./prepare-symex.sh

Then you can run different Eurus script to perform different tasks:

racket ./test-ex5.rkt
# or:# racket ./test-symex1.rkt

You can find out more details by reading ex/ex.sol and symex/symex.sol, as well as the test-*.rkt Eurus scripts. More documentations are on the way. For detailed steps, please see the "Other Commands" section.

Other Commands

• Automatically generate the core Yul parser:

  cd ./utils/YulAntlr/
  antlr4 -Dlanguage=Python3 Yul.g4

• Compile a solidity source code into Yul:

  # ex (examples)
  solc ./examples/ex/ex.sol --ir --overwrite -o ./examples/ex

• Translate original Yul to Eurus Yul:

  # examples
  python ./utils/yul_translator.py --yul ./examples/ex/ex0.yul
  python ./utils/yul_translator.py --yul ./examples/ex/ex1.yul
  python ./utils/yul_translator.py --yul ./examples/ex/ex2.yul
  python ./utils/yul_translator.py --yul ./examples/ex/ex3.yul

• Pre-process the Yul code and generated parsed json and config:

  # examples
  python ./utils/yul_parser.py --yul ./examples/ex/ex0.eurus.yul
  python ./utils/yul_parser.py --yul ./examples/ex/ex1.eurus.yul
  python ./utils/yul_parser.py --yul ./examples/ex/ex2.eurus.yul
  python ./utils/yul_parser.py --yul ./examples/ex/ex3.eurus.yul

• run test script

  racket ./test-ex5.rkt

• External ABI Encoding

  python ./utils/abiencode.py "['string'],['abcd']"

• External ABI Decoding

  python ./utils/abidecode.py "['string'],b'\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x20\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x06\x6d\x79\x6e\x61\x6d\x65\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'"

• External Keccak256

  python ./utils/keccak256.py "fun(uint256,bool)"