New answers tagged

1

Only the private key for the second input is used in this signature as this signature is only for the second input. The first input is P2PK and is ignored in this example as it is non-segwit so the standard non-segwit sighash algorithm is used for it.


0

Isn't each transaction dependent on a hash of the previous transaction? Yes and no. Yes, in that each transaction must be created using valid inputs (ie, referencing a valid UTXO to be consumed as an input). No, in that transactions are not 'dependant' on the previous transaction's hash in the same way that blocks are 'dependant' on the previous block's ...


0

Isn't each transaction dependent on a hash of the previous transaction? It is correct for most transactions apart from the coinbase transaction. The coinbase transaction is one that mints new coins through the mining process and as such does not have a preceding transaction it can reference. Wouldn't that mean all of the transactions for a particular ...


0

Yes, to get addresses from scriptPubKeys, you will need to do a pattern match. There are only a small number of address types each with their own fixed scriptPubKey pattern. Keep in mind that not all scriptPubKeys map to an address so you will find scriptPubKeys that have no address and you will need to handle those. Bitcoin Core has a pattern matcher for ...


0

Yes, every Bitcoin fork and others: Litecoin, Zcash, Dash, Decred, Dogecoin, Zcoin, Monero (~?), etc. You are looking for UTXO-based blockchains. The ones which you describe are account-based blockchains. I found this article that might help you under the limitations behind each design source: here.


0

Steps to debug will look like this. First of all you mentioned Bitcoin Cash, are you sure you are on the correct network? The explorer might be looking at the wrong network Which wallet did you use to send this, can you confirm the sending address is the same in the wallet as you expected from the site? The money may have already been forwarded but ...


0

Yes, you can prove you are the transaction's sender, by signing an arbitrary message with the transaction sender's private key. Here is an example using Electrum 3.3.6. Navigate the menu bar: Tools -> Sign/Verify message. Fill an arbitrary message (ex: This is a test message.) Enter the sender's address for that transaction (ex: ...


0

Any ideas or can someone be of assistance? I really don't know what to do TL;DR: Your money has been stolen. There is nothing you can do that has any significant probability to recover your $660. The thief got access to the private-keys stored in your wallet. a transaction sometime in March of 2019 was made and I didn't make any transactions in March ...


1

how can I find out who sent them? Realistically, you cannot. You could see which inputs were used in the transaction that sent you the bitcoins, and attempt to find their owner. But there is no information encoded into the transaction that states who sent it. If you met someone that claimed they were the one to send the coins to you, then you could ask ...


2

Are each of the wallets mentioned on the left hand side here always from the same person (ie. perhaps change wallets)? Or, is this transaction taking inputs from multiple (unrelated) people/wallets? It could be either. A single user's wallet might consume many UTXOs when crafting a transaction, but it is also possible for two (or more) people to supply ...


1

As per BIP 21, Bitcoin URIs are only allowed to contain a single address. You are free to develop your own format that supports multiple outputs, but it won't get very far unless you can convince other wallets to adopt it.


1

Assuming the two private keys are unrelated, the answer is no. The reason for this is simple: there are 3 unknowns (the two private keys, and the single secret k value), but only two equations (the ECDSA validation equation for both signatures). If a relation is known between the two private keys (like one is twice the other, or one is one higher than the ...


1

Lets say bitcoin become a global currency which replace fiat money Logically, if Bitcoin were to fully replace fiat money and be used for every transaction, then we should expect there would be some way of facilitating transactions easily, in pretty much every situation. Otherwise, people aren't going to adopt it if it is a worse solution that what is ...


1

Note: Although this answer is written for testnet, it is absolutely valid for the mainnet as well. The script will be similar, just the address encoding will be different (P2PKH start with 1 vs m for testnet as we use 0x00 as prefix in address base58check in mainnet). I tried to make transaction with Locktime on bitcoin testnet. I am not able to broadcast ...


1

Does this mean the company has received the payment for the investment? Yes Once a transaction has more than about 6 confirmations it is regarded as complete and the money is fully under the control of the recipient Can l claim the unspent output ? No and Yes. If the recipient hadn't yet spent the money you sent them, it is still their money not yours....


0

Adding onto @chytrik answer, the "proof" that it's impossible to find such a hash is purely probabilistic; perhaps there is some transaction hash which by sheer mind-boggling coincidence would not be hashable with all the others or any nonce to find a block with the necessary difficulty. If we supposed that this were the case, the next question would be how ...


2

I think that the answer to your question is no, a transaction which makes every block it is included in invalid does not exist. An important core property of a cryptographic hash function is that there is no discernable relationship between the input data, and output data. If such a relationship existed, then miners could 'cheat' by only creating blocks (...


1

After searching about this, i found out that each full node maintains a database with the set of unspent transaction outputs (UTXOs) in the memory. So When a new transaction is added, its UTXOs get updated accordingly (source). Also, a full node keeps track of all transactions that ever happened (source) and offer this: Filtering transactions and blocks ...


3

Signing transaction is a bit more complicated than just signing the hash of unsigned transaction Look at the explanations here: Redeeming a raw transaction step by step example required How to redeem a basic Tx?


0

In UTXO model, each transaction spends output from previous transactions and creates new output that can be spent by transactions later on operated by full nodes. Your wallet maintains a list of UTXOs associated with all addresses owned by the user, and the balance of the wallet is calculated as the sum of these unspent transactions. Take a look at this ...


0

The coinbase transactions e3bf3d07d4b0375638d5f1db5255fe07ba2c4cb067cd81b84ee974b6585fb468 and d5d27987d2a3dfc724e359870c6644b40e497bdc0589a033220fe15429d88599 both exist in two blocks. This problem was solved in BIP30 so this cannot happen again. BIP30 also dictates that it is the newest version of these transactions that is spendable.


3

A valid Bitcoin block has to include a minimum of one transaction, which is the coinbase transaction that pays out the block reward. Most of the early Bitcoin blocks did not include transactions that sent bitcoins from one party to other, but included only the coinbase transaction that paid out the newly minted bitcoins. In fact, the first transaction ...


1

If the transaction outputs associated to the public key has not been spent, then finding the funds associated with that public key will mostly be a trial and error method. Searching in outputs Most outputs in Bitcoin send funds to an address that is the hash of the public key. Pay-to-public-key (P2PK) is the only standard output that sends funds directly ...


1

In fact, the usual way to consult blockchains is using the public key (purportedly the public key of the searcher) as the result will be all the transactions in which the key is involved: https://www.blockchain.com/btc/address/1EwpnNBdFJykwxp6X8v9AfZnup9bgmrLE1 I suppose you're puzzled about the way to convert the public key to the public address, as the ...


0

Blockexplorers typically provide APIs that serve exactly that sort of data. For example the address call of the Blockchair API returns the latest 100 transactions the address was involved in. You would retrieve the data for example by calling curl https://api.blockchair.com/bitcoin-cash/dashboards/address/<someAddress> where you'll need to replace ...


1

The public key that you mentioned is indeed the key that was used to derive the P2SH(P2WPKH) address: 35yfMa3CRBiWny8DFdb4tUu9fn7fcdvVp9. The way in which a P2SH(P2WPKH) address is derived is as follows: 1. witness_script = hash160(pub_key) #this is equal to '4b9d2d3dd1174ad656754a0c664e7a129b131f3b' 2. witness_version = 0x00 #current SegWit version 3. ...


0

First Question: private key for what exactly? For the scriptPubKey that locks/encumbers the coins from being able to be spent. An output contains instructions for sending bitcoins. Value is the number of Satoshi (1 BTC = 100,000,000 Satoshi) that this output will be worth when claimed. ScriptPubKey is the second half of a script (discussed later). There ...


1

However, what is stopping someone, for example the recipient of the original transaction, to simply send in the same exact transaction with the same data and signature? Bitcoin does not have the concept of account balance but works on the concept of unspent transaction outputs (UTXOs). Each output of a transaction (except OP_RETURN ones) lead to the ...


1

the coin is gone from the sending wallet yet never arrived in the receiving wallet. Although we often say (or write) that coins are stored in wallets, it is important to remember this is just a convenient shorthand analogy for communication between people. In reality, Bitcoins don't exist in wallets, they are not stored in wallets and are not moved in and ...


2

the coin is gone from the sending wallet yet never arrived in the receiving wallet This isn't really a thing - The transaction is confirmed, which means the coins did move. In fact, the 0.0215682 sent has already been spent (I am assuming that is the payment amount, as the other output goes to a p2pkh address, which seems likely for a change output), which ...


1

The problem is the transaction fee doesn't depend on the values of inputs, but the number of inputs.


2

This is a process known as consolidation - If your wallet has several small inputs, many wallets will often try to combine them into a single change input during regular transactions, especially ones made with a low sat/byte feerate. This allows you to spend the coins in a smaller transaction during possibly high traffic times, when the feerate may be much ...


Top 50 recent answers are included