Quote from: damianmontero on January 09, 2015, 06:51:18 PM

Just updating the group.

We have created successfully a MultiSig Signature from JUST the Bitcoin Addresses (I think we're the first to do that, can't find anyone else online doing this.)
NO PUBKEY WAS USED (well the PubKey HASH was using, but not the original uncompressed full PubKey)

See transactions IN (the first from edmundedgar with the public Keys and the second from ME using the code below)

https://blockchain.info/address/3PcxJeW5f6Tp4mVAXe4ggGRvDREAPCMF4o

Thanks of course to everyone. And especially to edmundedgar for his amazing code examples INCLUDING his private keys (which makes live easier)

You need to do a:
1) download edmundedgar's Bitcoin Branching Transaction builder: https://github.com/edmundedgar/bitcoin-branching-transaction-builder
2) run "npm install bitcoinjs-lib" on that root directory
3) Make an app.js in the root of that project with the following code below (of course you have to have NODEjs installed)

Code:

var bitcoin = require('bitcoinjs-lib');
var BranchingTransactionBuilder = require('./src/branching_transaction_builder');
var ECKey = bitcoin.ECKey;
var Address = bitcoin.Address;
var scripts = bitcoin.scripts;

var BitcoinAddress1 = "1Fratqwo3Bu2FwMBzAex8WgDbmmGgJYLGH";
var BitcoinAddress2 = "112jFbM3Lp3qRSjezGFCv2rejT3UQ6rH5Z";

var addr1 = Address.fromBase58Check(BitcoinAddress1);
var addr2 = Address.fromBase58Check(BitcoinAddress2);

var branch1 = scripts.pubKeyHashOutput(addr1.hash);
var branch2 = scripts.pubKeyHashOutput(addr2.hash);

var branch_builder = new BranchingTransactionBuilder();
branch_builder.addSubScript(branch1);
branch_builder.addSubScript(branch2);
var branch_redeem_script = branch_builder.script();

var scriptPubKey = bitcoin.scripts.scriptHashOutput(branch_redeem_script.getHash())
var multisigAddress = bitcoin.Address.fromOutputScript(scriptPubKey).toString()
console.log("MultiSig Address: " + multisigAddress);
console.log("Redeem script: " + branch_redeem_script.buffer.toString('hex'));

console.log("");
console.log("Ok. Now you FUND the account with something of MORE than 0.0001 bitcoins (that's the minimum)");
console.log("");

// Make Transaction
var Transaction = bitcoin.Transaction;
var TransactionBuilder = bitcoin.TransactionBuilder;

var BitcoinToSendTo = "1GzUEmh472VwWydkhY4vDQMqY3xFpZRcKs";
var addrToSendTo = Address.fromBase58Check(BitcoinToSendTo);
var branchToSendTo = scripts.pubKeyHashOutput(addrToSendTo.hash);

// Just repeating what's above to reiterate and segregate the code
BitcoinAddress2 = "112jFbM3Lp3qRSjezGFCv2rejT3UQ6rH5Z";
addr2 = Address.fromBase58Check(BitcoinAddress2);
branch2 = scripts.pubKeyHashOutput(addr2.hash);

// Unspent amount: from https://blockchain.info/unspent?active=3PcxJeW5f6Tp4mVAXe4ggGRvDREAPCMF4o
   var test_output = {"unspent_outputs":[
   {
   "tx_hash":"3be8387e161bfc927cd4d06e4f1a800806ba509f74185709ee460967fe1d57c5",
   "tx_hash_big_endian":"c5571dfe670946ee095718749f50ba0608801a4f6ed0d47c92fc1b167e38e83b",
   "tx_index":74160687,
   "tx_output_n": 0,
   "script":"a914f08e151def9e83a2d96b44b5d87c719dcd374d8a87",
   "value": 200000,
   "value_hex": "030d40",
   "confirmations":0
   }
   ]};

var branch_redeem_script2 = branch_builder.script(branch_redeem_script.buffer.toString('hex'));
var spend_builder = new TransactionBuilder();
spend_builder.addInput(test_output['unspent_outputs'][0]['tx_hash_big_endian'], 0);
spend_builder.addOutput("1Dc8JwPsxxwHJ9zX1ERYo9q7NQA9SRLqbC", test_output['unspent_outputs'][0]['value'] - 10000);

var priv2 = ECKey.fromWIF('L3MRgBTuEtfvEpwb4CcGtDm4s79fDR8UK1AhVYcDdRL4pRpsy686');
var gp_builder = new BranchingTransactionBuilder(spend_builder);

// input 0 of the tx, second branch of 2 (index 1)
gp_builder.selectInputBranch(0, 1, 2);
gp_builder.signBranch(0, priv2, branch_redeem_script2, null, branchToSendTo);
var tx = gp_builder.build();

console.log(tx.toHex());

Sweet. We should probably:
1) Write a test for the other branch as well
2) Try sending the tx to a 0.10 node before using blochain.info/pushtx on it to prove that the network will really take these things when it starts to upgrade.