Log Parser

A TypeScript utility for parsing Medusa and Echidna fuzzing logs.

Web

Used in:

• https://getrecon.xyz/tools/medusa

• https://getrecon.xyz/tools/echidna

NPM

https://www.npmjs.com/package/@recon-fuzz/log-parser

Installation

yarn add @recon-fuzz/log-parser

Usage

import { processLogs, Fuzzer } from '@recon-fuzz/log-parser';

// Process Medusa logs
const medusaResults = processLogs(medusaLogContent, Fuzzer.MEDUSA);

// Process Echidna logs
const echidnaResults = processLogs(echidnaLogContent, Fuzzer.ECHIDNA);

API Reference

processLogs(logs: string, tool: Fuzzer): FuzzingResults

Processes fuzzing logs and returns structured results.

Parameters

• logs: string - The raw log content as a string
• tool: Fuzzer - The fuzzer tool used (Fuzzer.MEDUSA or Fuzzer.ECHIDNA)

Returns: FuzzingResults

interface FuzzingResults {
  duration: string;
  coverage: number;
  failed: number;
  passed: number;
  results: any[];
  traces: any[];
  brokenProperties: any[];
  numberOfTests: number;
}

Medusa and Echidna Conversion to Foundry

Converting Fuzzer Logs to Foundry Tests

Both Medusa and Echidna logs can be converted into Foundry test cases using the provided utility functions:

// For Echidna logs
import { echidnaLogsToFunctions } from '@recon-fuzz/log-parser';

const foundryTest = echidnaLogsToFunctions(
  echidnaLogs,
  "test_identifier",
  "brokenProperty",
  { roll: true, time: true, prank: true }
);

// For Medusa logs
import { medusaLogsToFunctions } from '@recon-fuzz/log-parser';

const foundryTest = medusaLogsToFunctions(
  medusaLogs,
  "test_identifier",
  { roll: true, time: true, prank: true }
);

The conversion handles:

• VM state manipulation (block numbers, timestamps)
• Actor simulation (pranks for different senders)
• Function call sequences
• Special data types (addresses, bytes)

Generated tests will include the exact sequence of calls that triggered the property violation, making it easy to reproduce and debug issues found during fuzzing.

Development

Requirements

• Node.js (>= 14.x)
• yarn or npm

Setup

1. Clone the repository
2. Install dependencies:

yarn install

Scripts

• yarn build - Build the package
• yarn test - Run tests
• yarn lint - Run linting

License

https://www.gnu.org/licenses/old-licenses/gpl-2.0.txt