Questions tagged [script]
A simple, stack-based, Forth-like programming language using "opcodes" to express spending conditions.
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Why CHECKMULTISIG bug can't be solved?
I was reading Mastering Bitcoin and I read about a bug in CHECKMULTISIG. If the starting ideas of this command should work like this
<Signature B><Signature C> M <Public key A><...
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What is the asm section of scriptSig
I am trying to understand the output from bitcoin-cli. The sample transaction's txid is 061959f1a3360d3781a870b2d43f73f7105b194b22f3765fcb9b8f545f9c8317, from block 222,222.
The asm section of ...
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What's the difference between decoderawtransaction and decodescript?
I'm looking for an explanation on the difference between the bitcoin CLI for decoderawtransaction and decodescript please.
From what I know, decodetransaction will undo the hash and ECDSA elliptic ...
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1
answer
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Is it correct to use OP_PUSHDATA1 to encode data less than 76 bytes?
According to https://en.bitcoin.it/wiki/Script#Constants, for data between 1-75 bytes, the length byte is directly appended to the data, without any OP_PUSHDATA op-codes.
However, I noticed that in ...
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Precedence of competing multisig spends
Imagine I want to create a multisig threshold (k-of-n) scheme where a spending transaction with more signatures takes precedence over other spending transactions with less signatures (but in both ...
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Is there a particular order in which transaction inputs are checked for script validity?
When a transaction is being checked for validity, is there a particular order that the inputs are evaluated for script correctness?
This might be relevant when determining what consensus changes might ...
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Error validating transaction: unexpected witness payload for non-witness script in a P2TR using script path
I am trying to create a raw transaction P2TR, spending a Taproot UTXO using the script path.
I did the following:
Create a random private key d and corresponding pubkey P (the internal pubkey)
...
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How to choose a nothing-up-my-sleeve (NUMS) point on secp256k1 for use in Taproot?
Per BIP-341, if you want to create a Taproot output that is only spendable via the script-path spend (and not a key-path spend), you must "pick as internal key a point with unknown discrete ...
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What is OP_RETURN_252?
The first scriptsig opcode in this coinbase transaction is OP_RETURN_252, followed a bit later by a OP_RETURN_188.
These don't show in this list of opcodes.
Digging the internet, I found this rust lib ...
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How do I set up a time-decay multisig?
I want to set up a multisig that requires fewer signatures as time goes by.
Let T be some time in the future (e.g. a year from now).
Before T, 2/3 signatures are required to unlock the UTXO (send ...
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Bitcoin script and unsecure ScriptPubKey
The following is taken from problem 3 in HW1 of CS 251 Stanford's course (https://cs251.stanford.edu/syllabus.html).
Alice is on a backpacking trip and is worried about her devices containing private ...
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I found a historical OP_HASH256 hashlock unspent output with 1 Bitcoin still in it, is it spendable?
The output:
Block Height
TXID
Output Index
Satoshi Amount
Locking Script
Status
211914
AF32BB06F12F2AE5FDB7FACE7CD272BE67C923E86B7A66A76DED02D954C2F94D
0
100000000
...
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Why wrapping P2PK inside P2SH didn't catch on?
Call it a pay-to-public-key-script-hash (P2PKSH), like so:
Locking script:
OP_HASH160 OP_DATA_20 redeem_script OP_EQUAL
Redeem script:
OP_DATA_20 pubkey OP_CHECKSIG
Unlocking script:
<push ...
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OP_SHA256 - Hashing the string representation
I'm building my own Bitcoin script interpreter for learning purposes.
I've compared my results with https://siminchen.github.io/bitcoinIDE/build/editor.html
And the script OP_16 OP_SHA256 which ...
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What are Known Bits in a bitcoin Transaction?
How do I know if my signatures has leak/weak signatures?
Is there a website or script where I can input my signatures to check for weak/leak Nonce part?
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Why has the Miniscript for this particular Policy changed over the past few months?
The "A 3-of-3 that turns into a 2-of-3 after 90 days" policy:
thresh(3,pk(key_1),pk(key_2),pk(key_3),older(12960))
compiled to this Miniscript a few months ago:
thresh(3,pk(key_1),s:pk(key_2)...
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Why is there a OP_NUMEQUAL opcode? Does OP_NUMEQUAL offer a subset of the functionality of OP_EQUAL?
There is a OP_EQUAL opcode that returns (from the Bitcoin wiki):
1 if the inputs are exactly equal, 0 otherwise
And a OP_NUMEQUAL opcode that returns:
1 if the numbers are equal, 0 otherwise
In ...
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Time delayed transactions as a solution for the inheritance problem?
Is it possible to construct a transaction which is delayed in time, more specifically blocks?
The idea being that you have a device which has a signed transaction, which sends all of your Bitcoin to ...
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Divide unknown future input amount sent to a given address amongst known recipients in known proportions?
Is there a way to divide an unknown future input amount received by a given address amongst three recipients with proportions of, for example 0.2 , 0.3, 0.5?
This would need to be done in such a way ...
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What OP_CODEs would push 254 bytes of data?
From BIP62 I would expect to use OP_PUSHDATA1 followed by uint8_t:
Pushing 76 to 255 bytes must use OP_PUSHDATA1.
But then from this answer, the link to variable-length integer makes it seem that a ...
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Meaning of SigScript in Satoshi Nakamoto's "Genesis" coinbase transaction
The Satoshi's coinbase transaction includes this following scriptSig:
...
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Optimistic Multisigs
I had an idea for an optimistic multisig scheme. In a 2/2 multisig where pubkey1 could spend any time and pubkey2 could only spend after a future block number, could you have a condition that allowed ...
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How does the CHECKSIGADD opcode work? How does it compare to its predecessor CHECKMULTISIG?
How does the CHECKSIGADD opcode (defined in the Tapscript BIP) BIP342 work? How does it compare to its predecessor CHECKMULTISIG?
The design of CHECKSIGADD was discussed in this StackExchange question....
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Why do invalid signatures in OP_CHECKSIGADD not push to the stack?
I've been working through the static test vectors provided by bitcoin core to implement an interpreter.
Some surprising behavior I found was that in the case of OP_CHECKSIGADD, if an invalid signature ...
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I can't find 3 words out of my 12 words recovery phrase that i saved. I hear i need to run a script I just need guidelines as a newbie on how to do it
So i can't find 3 words out of my 12 words recovery phrase that i saved. I just don't know how to go about the whole script thing. Really hoping someone could guide me step by step on it.
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Translating inputs (and outputs) to find addresses involved in transaction?
Is there a way for me to translate the input and output scripts in a bitcoin transaction?
I am building an application that lets you query different stats from the Bitcoin-network, down the line I ...
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Can The Redeem Script Consist Of Only 1 Public Key In P2SH Transactions:
I have a few questions relating to Bitcoin Signatures And P2SH:
Why is P2SH used as opposed to other forms? Is it still prevalent today - has SegWit made it redundant or less useful, if not, what is ...
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Where Is Signature Data Stored In Post-SegWit Transactions?
If i'm correct, i am pretty sure that signature data such as the scriptsigsize
and scriptsig is stored outside the Tx_Data of a Bitcoin transaction. But then where is it stored? Is it in the block or ...
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Why does `OP_CHECKSIGADD` allow TAPROOT keyspends?
My understanding is this sig version is only for taproot keyspends, why is it allowed to be used in OP_CHECKSIGADD?
https://github.com/bitcoin/bitcoin/blob/e826b22da252e0599c61d21c98ff89f366b3120f/src/...
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Is bitcoin script necessary?
satoshi created bitcoin script which is the language that the bitcoin client uses to handle most of the operations such as sending or verifying transactions.
was it necessary to have another language ...
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What is a sane Miniscript? How does it differ to a valid Miniscript?
What is a sane Miniscript? How does it differ to a valid Miniscript?
This was asked during a Bitcoin Core PR review club on Miniscript hosted by stickies-v on May 18th 2022.
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Is it possible to do OP_MOD with OP_GREATERTHAN and a few other opcodes?
Currently OP MOD is considered nonstandard in the Bitcoin protocol, but we
can for example combine OP SHA1 and OP GREATERTHAN to gain a similar effect.
https://www.cs.technion.ac.il/~idddo/...
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Reasons not to rename scriptPubKey and scriptSig to something more intuitive?
I realize that this is how Satoshi named them and there was some reasoning behind these names, but even after years of using them, I find them weird and confusing, especially when e.g. explaining them ...
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Is weighed multi-sig wallet possible?
In a multi-sig wallet, each of the public keys is unique. Is it possible to create weighted multi-sig wallet, such that one private key has more power than the others?
Case 1: typical Example (need 2 ...
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How would one turn a Miniscript tree into a Taproot tree with Taproot'd Miniscript?
How would one turn a Miniscript "tree" into a Taproot tree with Taproot'd Miniscript?
(To be clear unlike a Taproot tree a Miniscript tree likely would't be surfaced to the user. Breaking ...
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Transactions with invalid or non-parseable Script
During parsing of Bitcoin data from blockchain, I found many transactions which has invalid script (example 37b828de0da38f0b3b9ec09f6f8b7883c3202a99a285b0b0087f19f9cbf526d9,...
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What is the script signature and PUSHDATA operation? [duplicate]
In bitcoin transactions, there is a part of the transaction known as the scriptSig. What does this mean? Also, what is the scriptSig (PUSHDATA opcode) operation.
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How to submit nonstandard scriptPubKey transaction to bitcoind in regtest mode?
I'm trying to replicate an algebraic puzzle I saw in the scriptPubKey of a testnet transaction:
OP_2DUP
OP_ADD
6e
OP_EQUAL
I think the intent was for this output to be spendable by a scriptSig of ...
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How did testnet transaction b6714e05dd014cc92de09271886e62d85e7d41dd44fad417c520eb51d57f94c0 validate?
Testnet transaction c474c67cabc13f74c65e7cf503db971d5ba176794bff7de36f46d51ca675cf3a locked 0.0005BTC with a simple math script:
OP_2DUP
OP_ADD
5102
OP_EQUALVERIFY
OP_SUB
230d
OP_EQUAL
Transaction ...
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Simplicity vs Miniscript [duplicate]
It is clear that both simplicity and Miniscript aims to extend and improve upon the bitcoin script. However what are the differences between them and the pros and cons they both have against the other?...
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Newbie, please help, I'm totally clueless about Bitcoin and the rest of them and I need help [duplicate]
I'm a beginner and I'm new to everything about Bitcoin, crypto and
everything. Please, I need help,anyone??
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Why does this not return TRUE?
scriptSig: <pubKey>
scriptPubKey: <pubKey> OP_EQUALVERIFY
The stack has <pubKey>, <pubKey> and then OP_EQUALVERIFY. So why, does it not return TRUE, even when the recent two ...
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1
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Are attempts to spend from a timelocked UTXO rejected?
Background
I was reading a bit about Bitcoin time locked transactions within the context of the Lightning Network. One thing that was never explained is what happens when one tries to prematurely ...
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Using EQUALVERIFY with different public keys, but generated from the same seed
I am building certain system that involves Bitcoin and therefore I need to understand well how it works under the hood.
In order to receive funds, for every new transaction new public key and its hash ...
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How to regularly restart bitcoind after some period of time on Linux
If, like me you wish to automatically restart bitcoind after some period of time, or if it crashes at least it will restart sometime on it's own you know that it can take a long time on Linux before ...
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Q's about P2WPKH
I got some btc in testnet, here are the outputs.
this is the UTXO that i get my btc
{
"value": 17.24756333,
"n": 1,
"scriptPubKey": {
"asm": "...
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How can the genesis block contain arbitrary data on it if the script is invalid?
The coinbase transaction from the genesis block contains this script: ...
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How transactions script work?
I am trying to learn Bitcoin in some technical details, but I don't really understand the process of locking and unlocking scripts. I know that for what they are using, but can someone explain me some ...
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Is it possible to design a recursive covenant opcode that results in a full node stuck in an infinite verification loop?
Is it possible to design a new opcode enabling recursive covenants that could result in a full node stuck in an infinite loop of verifying transactions? (Obviously this would never be considered for a ...
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Trying to understand a nonstandard transaction in bitcoin tests
I am trying to implement a bitcoin script interpreter and today I stumbled upon a nonstandard transaction in tx_valid.json which gave me a lot of headaches. The transaction in question has the ...
