EtherSolve

EtherSolve is a tool for Control Flow Graph (CFG) reconstruction and static analysis of Solidity smart-contracts from Ethereum bytecode.

The tool is based on the peer-reviewed pubblication

Michele Pasqua, Andrea Benini, Filippo Contro, Marco Crosara, Mila Dalla Preda, and Mariano Ceccato. "Enhancing Ethereum smart-contracts static analysis by computing a precise Control-Flow Graph of Ethereum bytecode". In: Journal of Systems and Software (pp. 1-18), Elsevier, 2023. DOI: 10.1016/j.jss.2023.111653

That is a revised and extended version of the peer-reviewed publication

Filippo Contro, Marco Crosara, Mariano Ceccato, and Mila Dalla Preda. "EtherSolve: Computing an Accurate Control-Flow Graph from Ethereum Bytecode". In: Proceedings of the 29^th IEEE/ACM International Conference on Program Comprehension (pp. 127-137), IEEE, 2021. DOI: 10.1109/ICPC52881.2021.00021

Vulnerability Detection

The tool also provides modules for the detection of Ethereum vulnerabilities. It currently supports Re-entrancy and Tx.origin vulnerabilities.

Usage

JAR

The simplest way to try EtherSolve is through the provided EtherSolve.jar (link).

Usage: ethersolve [-hV] [--re-entrancy] [--tx-origin] [-o=<outputFilename>] (-c | -r) (-j | -H | -s | -d) <source>
EtherSolve, build an accurate CFG from Ethereum bytecode.
      <source>                    Bytecode string or file containing it.
  -h, --help                      Show this help message and exit.
  -V, --version                   Print version information and exit.
      --re-entrancy               Execute the Re-entrancy detector and save output.
      --tx-origin                 Execute the Tx.origin detector and save output.
  -o, --output=<outputFilename>   Output file name.
  -c, --creation                  Parse bytecode as creation code.
  -r, --runtime                   Parse bytecode as runtime code.
  -j, --json                      Export a Json report.
  -H, --html                      Export a graphic HTML report. Graphviz is required!
  -s, --svg                       Export a graphic SVG image. Graphviz is required!
  -d, --dot                       Export a dot-notation file.

The source can be the EVM bytecode string or a path to a file containing it. Specify if the bytecode is creation code (-c) or runtime code (-r), and the desired output type.
The tool has been tested on Linux x64 with Java 11.0.8. To produce a graphical output (HTML or SVG) Graphviz is required.

To run the Re-entrancy and the Tx.origin validators add the --re-entrancy and the --tx-origin options, respectively. The tool will create a CSV file containing the detected vulnerabilities and their location in the code.

Examples

To analize the bytecode of a smart-contract contained in a given file, you can run following:

# Generate HTML report for creation-code source file
java -jar EtherSolve.jar -c -H path/to/bytecode/file.evm

# Generate JSON report in 'report.json' for creation-code source file
java -jar EtherSolve.jar -c -j -o report.json path/to/bytecode/file.evm

# Generate HTML report in 'index.html' for runtime-code source file
java -jar EtherSolve.jar -r -H -o index.html path/to/bytecode/file.evm

# Generate HTML report in 'index.html' for creation-code source file with Re-entrancy detection analysis
java -jar EtherSolve.jar -c -H -o index.html --re-entrancy path/to/bytecode/file.evm

Gradle

To build from source and run the project you should use gradle (minimum Gradle supported version: 5.2.1). To build from source Java 8 is required.

EtherSolve is composed of five modules.

• Core: it contains the main procedures to parse the bytecode and build the CFG.
• Abi: it contains the validation methods (see the paper) and a prototype for an Abi extraction.
• UI: it contains the procedures to graphically represent the CFG using Graphviz and to produce the HTML report. It also contains the command line interface and the main class of the tool.
• SecurityAnalysis: it contains the security analyser and the dataset tester used for the comparison with the SolidiFI survey.
• WebApp: it contains a simple SpringBoot server to provide analysis via APIs (unmantained).

The following Gradle tasks are available.

• bootRun: run the project as a Spring Boot application.
• runCoreMain: run the main class of the Core module, that analyses a sample bytecode written in the Main class, producing a JSON output.
• runIRExtractor: run the extractor to get the intermediate representation used for the analysis.
• runSecurityAnalyser: run the main class of the Core module, that analyses a sample bytecode.
• jar: build a JAR for each module. The only JAR having an entry point is the one of the UI module. The artifact output can be found in the UI/build/libs folder.

For the full list run gradle tasks.

Replication Package

The material to replicate the results presented in the JSS 2023 publication can be found in the JSS Replication Package.