daopunk’s gists

daopunk / readEthStorageNestedMapping.js

Last active June 30, 2022 22:10

getMappingItem to access nested mapping elements in struct in Ethereum state with ethers.js

	async function getNestedMappingStruct(slot, contractAddress, key, item, nestedKey) {
	const paddedSlot = utils.hexZeroPad(slot, 32);
	const paddedKey = utils.hexZeroPad(key, 32);
	const itemSlot1 = utils.keccak256(paddedKey + paddedSlot.slice(2));
	const itemSlot = BigNumber.from(itemSlot1).add(item).toHexString();
	const paddednestedKey = utils.hexZeroPad(nestedKey, 32);
	const itemNestedSlot = utils.keccak256(paddednestedKey + itemSlot.slice(2));

	return getUint256(itemNestedSlot, contractAddress);
	}

daopunk / readEthStorageMappingStruct.js

Created June 30, 2022 21:42

getMappingItem to access mapping elements in struct in Ethereum state with ethers.js

	async function getMappingStruct(slot, contractAddress, key, item, type) {
	const paddedSlot = utils.hexZeroPad(slot, 32);
	const paddedKey = utils.hexZeroPad(key, 32);
	const itemSlot1 = utils.keccak256(paddedKey + paddedSlot.slice(2));
	const itemSlot = BigNumber.from(itemSlot1).add(item).toHexString();

	switch (type) {
	case "string":
	return await getShortStr(itemSlot, contractAddress);
	case "bytes":

daopunk / readEthStorageMappingItem.js

Created June 30, 2022 21:41

getMappingItem to access mapping elements in Ethereum state with ethers.js

	async function getMappingItem(slot, contractAddress, key) {
	const paddedSlot = utils.hexZeroPad(slot, 32);
	const paddedKey = utils.hexZeroPad(key, 32);
	const itemSlot = utils.keccak256(paddedKey + paddedSlot.slice(2));
	return await getUint256(itemSlot, contractAddress);
	}

daopunk / readEthStorageArrayItem.js

Created June 30, 2022 21:35

getArrayItem to access array items in Ethereum state with ethers.js

	async function getArrayItem(slot, contractAddress, item, byteSize) {
	const hashedSlot = utils.keccak256(utils.hexZeroPad(slot, 32));
	const itemsPerSlot = 32 / byteSize;
	let itemPos = item;

	for (let s=1; s<item; s++) {
	if (item >= itemsPerSlot) {
	itemPos - itemsPerSlot;
	}
	}

daopunk / readEthStorageBytePacked.js

Created June 30, 2022 21:17

getBytePackedVar to access variables packed into 32 byte slot in Ethereum state with ethers.js

	async function getBytePackedVar(slot, contractAddress, byteShift, byteSize) {
	const paddedSlot = utils.hexZeroPad(slot, 32);
	const storageLocation = await ethers.provider.getStorageAt(contractAddress, paddedSlot);
	let result = "";
	let altByteSize = 0;
	let altByteShift = 0;
	let check = false;

	if (byteSize <= 6) {
	return BigNumber.from(storageLocation).shr(byteShift * 4).mask(byteSize * 4 * 2).toNumber().toString(16);

daopunk / StorageEx.sol

Last active June 30, 2022 20:56

A storage example solidity smart contract for reference to Medium article: https://medium.com/@cryptoAnarchy

	contract StorageEx {
	enum Vote { Absent, Yes, No }

	// slot 0x0 Big Endian (first byte stored first)
	bytes2 a = 0xAce0;
	bytes4 b = 0xBebeAce0;
	bytes4 c = 0xCafeBebe;
	bytes6 d = 0xDebeCafeBebe;
	bytes8 e = 0xEbeeDebeCafeBebe;
	bytes8 f = 0xFebeeAceCafeBebe;

daopunk / readEthStorageShortString.js

Last active June 30, 2022 20:49

getShortStr to access <=32 byte strings in Ethereum state with ethers.js

	async function getShortStr(slot, contractAddress) {
	const paddedSlot = utils.hexZeroPad(slot, 32);
	const storageLocation = await ethers.provider.getStorageAt(contractAddress, paddedSlot);
	const storageValue = BigNumber.from(storageLocation);

	const stringData = utils.toUtf8String(
	storageValue.and(MaxUint256.sub(255)).toHexString()
	);
	return stringData.replace(/\x00/g, '');
	}

daopunk / readEthStorageEthersConstants.js

Created June 30, 2022 20:20

Reusable ethers.js methods for cleaner code

	const { ethers } = require('hardhat');
	require('dotenv').config();

	// ethers methods
	const utils = ethers.utils;
	const BigNumber = ethers.BigNumber;
	const MaxUint256 = ethers.constants.MaxUint256

daopunk / readEthStorageNumber.js

Created June 30, 2022 20:19

getUint256 function to access 32 byte numbers in Ethereum state with ethers.js

	async function getUint256(slot, contractAddress) {
	const paddedSlot = utils.hexZeroPad(slot, 32);
	const storageLocation = await ethers.provider.getStorageAt(contractAddress, paddedSlot);
	const storageValue = BigNumber.from(storageLocation);
	return storageValue;
	}

daopunk / readEthStorageLongString.js

Last active June 30, 2022 20:50

getLongStr to access >32 byte strings in Ethereum state with ethers.js

	async function getLongStr(slot, contractAddress) {
	const paddedSlot = utils.hexZeroPad(slot, 32);
	const storageReference = await ethers.provider.getStorageAt(contractAddress, paddedSlot);

	const baseSlot = utils.keccak256(paddedSlot);
	const sLength = BigNumber.from(storageReference).shr(1).toNumber();
	const totalSlots = Math.ceil(sLength / 32);

	let storageLocation = BigNumber.from(baseSlot).toHexString();
	let str = "";

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