embark/lib/modules/profiler/fuzzer.js

95 lines
2.9 KiB
JavaScript

const utils = require('web3-utils');
const u = require('../../utils/utils.js');
// generates random inputs based on the inputs of an ABI
class ContractFuzzer {
constructor(embark) {
this.embark = embark;
this.logger = embark.logger;
this.events = embark.events;
}
// main function to call, takes in iteration number and a contract and returns a map object
// composed of method names -> fuzzed inputs.
generateFuzz(iterations, contract) {
const self = this;
let fuzzMap = {};
contract.abiDefinition.filter((x) => x.inputs && x.inputs.length != 0 && x.type != "event").forEach((abiMethod) => {
let name = abiMethod.type === "constructor" ? "constructor" : abiMethod.name;
let inputTypes = abiMethod.inputs.map(input => input.type);
fuzzMap[name] = {};
for (let i = 0; i < iterations; i++) {
fuzzMap[name][i] = inputTypes.map(input => this.getTypeFuzz(input));
self.logger.trace(name);
self.logger.trace("iteration: " + i + "\n" + fuzzMap[name][i]);
}
});
self.logger.trace('\n');
return fuzzMap;
}
getTypeFuzz(typeString) {
const self = this;
// Group 0: uint256[3]
// Group 1: uint256
// Group 2: uint
// Group 3: 256
// Group 4: [3]
// Group 5: 3
let regexObj = typeString.match(/((bool|int|uint|bytes|string|address)([0-9]*)?)(\[([0-9]*)\])*$/);
let type = regexObj[1];
let kind = regexObj[2];
let size = regexObj[3];
let array = regexObj[4];
let arraySize = regexObj[5];
switch(true) {
case array !== undefined: {
// if it's a dynamic array pick a number between 1 and 256 for length of array
let length = arraySize === undefined || arraySize === null || arraySize === '' ? Math.floor((Math.random() * 256) + 1) : arraySize;
return self.generateArrayOfType(length, type);
}
case kind == "bool":
return self.generateRandomBool();
case kind == "uint" || kind == "int":
return self.generateRandomInt(size);
case kind === "bytes" && size !== undefined:
return self.generateRandomStaticBytes(size);
case kind === "string" || kind === "bytes":
return self.generateRandomDynamicType();
case kind === "address":
return self.generateRandomAddress();
default:
throw new Error("Couldn't find proper ethereum abi type");
}
}
generateRandomBool() {
return u.sample([true, false]);
}
generateArrayOfType(length, type) {
var arr = [];
for (var i = 0; i < length; i++) arr.push(this.getTypeFuzz(type));
return arr;
}
generateRandomDynamicType() {
return Math.random().toString(36).slice(2);
}
generateRandomStaticBytes(size) {
return utils.randomHex(size);
}
generateRandomInt(size) {
return utils.toBN(utils.randomHex(size / 8));
}
generateRandomAddress() {
return utils.randomHex(20);
}
}
module.exports = ContractFuzzer;