How do I convert my The DAO tokens into ethers using the withdrawal contract after the hard fork?

Question

The DAO contract was attacked on 17th June 2016 where the attacker drained about USD 50 million worth of ethers using a recursive call vulnerability in The DAO contract code.

The attacker drained the stolen ethers into a few child DAOs and the Robin Hood Group drained the remaining funds into other child DAOs.

A hard fork is scheduled for block #1,920,000 (in around 24 hours time, ~ 23:26 20/07/2016 Australian Eastern Standard Time) to transfer the ethers from The DAO contract and it's child DAOs into a Withdrawal contract.

Once the hard fork has passed, how do I convert my The DAO tokens into ethers?

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The DAO Refunds

• [THIS] How do I convert my The DAO tokens into ethers using the withdrawal contract after the hard fork?
• How do I get a refund for the amount I paid in excess of 1 ether to 100 The DAO tokens
• How do I get a refund for my The DAO tokens that was split into a child DAO?
• How do I convert my The DAO tokens into ethers on the Ethereum Classic chain?
• How to conditionally send ethers to another account post-hard-fork to protect yourself from replay attacks

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Update 13:31 Jul 20 2016 UTC

The Withdrawal contract has a balance of 11,597,664.781027947 Ether ($145,318,739.71).

A successful hard fork. Happy Hard Fork Everyone! Good work Devs and other involved.

Update 22:31 Jul 20 2016 UTC

The Withdrawal contract now has a balance of 6,369,298.685677664 Ether ($79,807,312.53). About 45% of DAOs have now been converted into ETHs, over 1,506 transactions.

Update 18:04 Jul 23 2016 UTC

The Withdrawal contract now has a balance of 4,595,418.245476871 Ether ($65,944,251.82). About 60% of DAOs have now been converted into ETHs, over 3,887 transactions.

Here's a chart from https://slacknation.github.io/medium/11/11.html:

Update 23:18 Aug 1 2016 UTC

Update 14:58 Sep 6 2016 UTC

13.55% balance remaining.

Answer 1

Update Mar 29 2017

The latest instructions can be found at The DAO Refunds.

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Notes

• This Withdrawal contract only allows the conversion of The DAO tokens (DAO) into ethers (ETH) at the rate of 100 DAOs = 1 ETH.
• The way the Withdrawal contract has been coded means that you HAVE to approve the transfer of ALL DAOs in your account, as the Withdrawal contract will only transfer ALL of your DAOs in the one go. If you do not approve all of your DAOs to be transferred, the withdraw() function will throw an error, consuming all the gas specified with the transaction.

• Anyone who bought DAOs in the last two weeks of The DAO crowdfunding phase paid more than 1 ETH per 100 DAOs. The amount in excess of 1 ETH per 100 DAOs was stored in The DAO's extraBalance account. The balance of the extraBalance account has now been transferred into the curator's multisig wallet.

  There is a separate process for purchasers who paid more than 1 ETH per 100 DAOs to get refunded the extra amount paid (over the 1 ETH per 100 DAOs). This process is not covered in this answer, but rest assured that the developers are trying their best to fairly distribute the excess funds back to the original DAO buyers.

  See How do I get a refund for the amount I paid in excess of 1 ether to 100 The DAO tokens which will be updated when further details are announced.

• If you have executed a legitimate split from The DAO, your DAO balance has been moved to the child DAO and your DAO balance in The DAO is zeroed. As your DAO balance in The DAO is zero, you will not be able to convert your DAOs to ETHs using the procedure in this Q&A.

  See How do I get a refund for my The DAO tokens that was split into a child DAO? as you will need to contact TheDAOCurator for them to arrange for your refund.

• Wait for some time after the hard fork before attempting to convert your DAOs into ETHs. There is no deadline for the withdrawals. The safest thing to do is wait.

Update 06:33 Oct 26 2016 Some DAO -> ETH transactions are failing due to rounding errors. See Why Are My The DAO To ETH Refunds Failing?.

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Withdrawal Method 1 - MyEtherWallet

1. Go to http://www.myetherwallet.com/#the-dao

2. Upload / Paste your Keystore file / Private Key to access your wallet.

3. Press big red button.

4. Confirm that you are sure you want to withdraw.

5. Wait a couple seconds and 2 transaction links will appear. Wait about 30 more seconds and check the balance of your account on Etherscan. You should have more ETH and 0 DAO. I (@tayvano) confirmed it worked @ 6:43AM PDT using the MyEtherWallet donation account: http://etherscan.io/address/0x7cb57b5a97eabe94205c07890be4c1ad31e486a8

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Withdrawal Method 2 - Ethereum Wallet

The (circularly referenced) article How to use the Withdraw Contract with Mist by Griff Green provides a step-by-step screen printed guide similar to the instructions below.

Make sure that you have downloaded Ethereum Wallet 0.8.1 or later.

The first time you start Ethereum Wallet 0.8.1, select "Yes" to the question "Do you want to activate the chain in which funds linked to the exploit are restored to a contract where they can be withdrawn by The DAO token holders?". You have now made the choice to use the hard-forked Ethereum chain.

If Ethereum Wallet is freezing, see UPDATE 23 Jul 2016 in How to remove The DAO contract from Ethereum Wallet (Mist) watch list as it is freezing?.

If you have not already added a watch on The DAO contract, see The DAO - How to add and watch the DAO contract. This step will give you access to approve the transfer of DAOs to the Withdrawal contract.

If you cannot find the Approve function as required below, reload the JSON interface for The DAO contract using the steps immediately above. If you have trouble using the Ethereum Wallet with a freezing display, try removing The DAO contract from the Ethereum Wallet (How to remove The DAO contract from Ethereum Wallet (Mist) watch list as it is freezing?), then watch The DAO contract again.

Add a watch on The DAO Withdrawal contract. Use the same procedure as in the link directly above, but set:

• Contract Name: The DAO Withdrawal
• Contract Address: 0xbf4ed7b27f1d666546e30d74d50d173d20bca754
• JSON Interface: [{"constant":false,"inputs":[],"name":"trusteeWithdraw","outputs":[],"type":"function"},{"constant":false,"inputs":[],"name":"withdraw","outputs":[],"type":"function"},{"constant":true,"inputs":[],"name":"mainDAO","outputs":[{"name":"","type":"address"}],"type":"function"},{"constant":true,"inputs":[],"name":"trustee","outputs":[{"name":"","type":"address"}],"type":"function"}]

23:47 20/07/2016 AEST - I have confirmed that the process below using the Ethereum Wallet works

Approve The Transfer Of Your DAOs To The Withdrawal Contract

1. Get the account address from which you want to convert your DAOs into ETHs

   • Under the Wallet menu, select the account from which you want to convert DAOs into ETH.
   • Double click on the account address and copy the address into your clipboard using Control-C in Linux or Windows, or Command-C on a MacBook.

2. Get the balance of the account from which you want to convert your DAOs into ETHs

   • In the Contract menu, select The DAO contract.
   • Scroll down to the Balance of function under the Read From Contract column on the left.
   • Paste the address in your clipboard into the owner-address field.
   • Double click on the Balance displayed and copy the balance into your clipboard using Control-C in Linux or Windows, or Command-C on a MacBook.

3. Approve the transfer of your account's DAO balance to the Withdrawal contract address

   • In the Contract menu, select The DAO contract.
   • Under the Write To Contract column on the right, select the Approve function.
   • Paste the balance from your clipboard into the amount-256 bits unsigned integer field using Control-V in Linux or Windows, or Command-V on a MacBook.
   • Enter the Withdrawal contract address 0xbf4ed7b27f1d666546e30d74d50d173d20bca754 in the spender-address field.
   • Under the Execute from field, select the account from which you want to convert your DAOs into ETHs.
   • Leave the Send ETHER field as 0.
   • Click on Execute and enter your account password.
   • You should get a transaction confirmation message.

Execute The Withdrawal Contract Function

1. Withdraw ETH from the Withdrawal contract

   • In the Contract menu, select The DAO Withdrawal contract
   • Under the Write To Contract column on the right, select the Withdraw function.
   • Under the Execute from field, select the account from which you want to convert your DAOs into ETHs.
   • Click on Execute and enter your account password.
   • You should get a transaction confirmation message.
   • Wait a short while and your ether balance should update. If not, restart Ethereum Wallet.

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Withdrawal Method 3 - geth

Make sure that you are running geth version 1.4.10 or later. And run your geth commands with the --support-dao-fork option so that you are on the hard-forked blockchain. For example:

geth --support-dao-fork console

The --support-dao-fork setting is persisted between separate executions of geth, so you only have to specify this parameter once.

Confirm your geth version using

user@Kumquat:~$ geth version
Geth
Version: 1.4.10-stable
Protocol Versions: [63 62]
Network Id: 1
Go Version: go1.5.1
OS: linux

Here is the process using geth to convert your DAOs into ETHs for your account {x}.

00:14 21/07/2016 AEST - I have confirmed that the process below using geth works

geth --support-dao-fork --unlock {your account} console
...
Unlocking account {your account}
Passhrase: {enter your passphrase}
// Allow your blockchain to sync

> var account = "{your account}";
undefined

> var theDAOAddress = "0xBB9bc244D798123fDe783fCc1C72d3Bb8C189413";
undefined

> var theDAOWithdrawalAddress = "0xbf4ed7b27f1d666546e30d74d50d173d20bca754";
undefined

> var theDAOABIFragment = [{"constant":false,"inputs":[{"name":"_spender","type":"address"},{"name":"_amount","type":"uint256"}],"name":"approve","outputs":[{"name":"success","type":"bool"}],"type":"function"}, {"constant":true,"inputs":[{"name":"_owner","type":"address"}],"name":"balanceOf","outputs":[{"name":"balance","type":"uint256"}],"type":"function"}];
undefined

> var theDAO = web3.eth.contract(theDAOABIFragment).at(theDAOAddress);
undefined

> var approve = theDAO.approve(theDAOWithdrawalAddress, theDAO.balanceOf(account), {from: account});
undefined

> eth.getTransaction(approve);
// Repeat the command above until you see that blockNumber is not null

// Wait a few blocks (~ 15 seconds each) for your approve transaction to get mined

> var theDAOWithdrawalABIFragment = [{"constant":false,"inputs":[],"name":"withdraw","outputs":[],"type":"function"}];
undefined

> var theDAOWithdrawal = web3.eth.contract(theDAOWithdrawalABIFragment).at(theDAOWithdrawalAddress);
undefined

> var withdrawal = theDAOWithdrawal.withdraw({from: account});
undefined

> eth.getTransaction(withdrawal);
// Repeat the command above until you see that blockNumber is not null

// Wait a few blocks (~15 second each) and check your new account balance
web3.fromWei(eth.getBalance(account), "ether")
11.023456789012345678

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Withdrawal Method 4 - Ethereum Wallet In Mist Browser Mode

Make sure that you have downloaded Ethereum Wallet 0.8.1 or later.

The first time you start Ethereum Wallet 0.8.1, select "Yes" to the question "Do you want to activate the chain in which funds linked to the exploit are restored to a contract where they can be withdrawn by The DAO token holders?". You have now made the choice to use the hard-forked Ethereum chain. Exit from Ethereum Wallet.

Now run the Ethereum Wallet in the Mist browser mode using the following command from the subdirectory you installed the software in:

• In Linux & the MacBook

  ./Ethereum-Wallet --mode mist & 
  

• In Windows

  Ethereum-Wallet --mode mist
  

(Alternatively, you can download the Mist browser directly - see @johnmardlin answer below).

Then:

1. Make sure you've selected only the account which you used to purchase "The DAO" tokens.
2. In Mist browse to https://slacknation.github.io/medium/12/12.html
3. Click on "Approve", wait for one block
4. Click on "Refund", wait for one block

(Added Method 4 as requested by @slacknation in https://www.reddit.com/r/ethereum/comments/4tx13d/how_do_i_withdraw_dao_tokens_eth_after_hf_update/)

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Withdrawal Process Explanation

There is a two step process to convert your DAOs into ETHs.

a) Approve The Transfer Of DAOs From The DAO To The Withdrawal Contract

The first step is to approve the transfer of DAOs from The DAO into the Withdrawal contract. This is done by calling The DAO's approve(...) function, listed below:

From The DAO's source code, here is the TokenInterface.approve() function definition:

/// @notice `msg.sender` approves `_spender` to spend `_amount` tokens on
/// its behalf
/// @param _spender The address of the account able to transfer the tokens
/// @param _amount The amount of tokens to be approved for transfer
/// @return Whether the approval was successful or not
function approve(address _spender, uint256 _amount) returns (bool success);

Here is the Token.approve(...) function that implements the function defined above:

function approve(address _spender, uint256 _amount) returns (bool success) {
    allowed[msg.sender][_spender] = _amount;
    Approval(msg.sender, _spender, _amount);
    return true;
}

Once you have called The DAO's approve(...) function, you have created an approval for the Withdrawal contract to transfer your DAOs into the Withdrawal contract.

b) Convert Your DAOs Into ETHs With The Withdrawal Contract

The second step is to call the Withdrawal contract's withdraw() function to transfer DAOs from The DAO into the Withdrawal contract, and for the Withdrawal contract to send your account the equivalent amount in ETH.

Here is the source code for the withdraw() function:

function withdraw(){
    uint balance = mainDAO.balanceOf(msg.sender);

    if (!mainDAO.transferFrom(msg.sender, this, balance) || !msg.sender.send(balance))
        throw;
}

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Source of information

User @lefteris in thedao.slack.com stated that The DAO Withdrawal contract can be found at 0xbf4ed7b27f1d666546e30d74d50d173d20bca754 and the process to convert DAOs into ETHs are the following:

a) call dao.approve("0xbf4ed7b27f1d666546e30d74d50d173d20bca754", dao.balanceOf(youraccount))
b) call withdrawContract.withdraw()

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Withdrawal Contract Source Code And Address

The source code for the Withdrawal contract can be found at 0xbf4ed7b27f1d666546e30d74d50d173d20bca754 and is as follows:

contract DAO {
    function balanceOf(address addr) returns (uint);
    function transferFrom(address from, address to, uint balance) returns (bool);
    uint public totalSupply;
}

contract WithdrawDAO {
    DAO constant public mainDAO = DAO(0xbb9bc244d798123fde783fcc1c72d3bb8c189413);
    address public trustee = 0xda4a4626d3e16e094de3225a751aab7128e96526;

    function withdraw(){
        uint balance = mainDAO.balanceOf(msg.sender);

        if (!mainDAO.transferFrom(msg.sender, this, balance) || !msg.sender.send(balance))
            throw;
    }

    function trusteeWithdraw() {
        trustee.send((this.balance + mainDAO.balanceOf(this)) - mainDAO.totalSupply());
    }
}

From The DAO's source code (referenced above), here is the Token.transferFrom(...) function:

function transferFrom(
    address _from,
    address _to,
    uint256 _amount
) noEther returns (bool success) {

    if (balances[_from] >= _amount
        && allowed[_from][msg.sender] >= _amount
        && _amount > 0) {

        balances[_to] += _amount;
        balances[_from] -= _amount;
        allowed[_from][msg.sender] -= _amount;
        Transfer(_from, _to, _amount);
        return true;
    } else {
        return false;
    }
}

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Some Further References

• TheDAO hack FAQ: How did the attack happen on 17 June 2016?
• What is a recursive calling vulnerability?
• How many ethers have been drained through the recursive call attacks on The DAO?

Answer 2

This is a fairly straight forward method using Mist.

1. Make sure you've selected only the account which you used to purchase "The DAO" tokens.
2. In Mist browse to https://slacknation.github.io/medium/12/12.html
3. Click on "Approve", wait for one block
4. Click on "Refund", wait for one block