Questions tagged [sighash-flags]
The sighash-flags tag has no usage guidance.
21
questions
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Strange double-spending attack possibility
In Bitcoin you can have different UTXO with different public keys in a single transaction.
So suppose someone broadcasts a transaction with sending 10000 BTC. Theoretically I can copy this transaction,...
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1
answer
98
views
Trying to make SIGHASH_SINGLE transaction
I am trying to make a SIGHASH_SINGLE transaction.
I have two inputs, one output. I understand that second input can be not signed (really?).
Script I have is:
#!/usr/bin/env python3
import hashlib
...
- 141
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1
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167
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What is the transaction hash preimage for different values of SIGHASH (not SIGHASH_ALL) in P2PKH?
I have a few questions regarding the transaction hash preimage when signing with different values of the SIGHASH flag in the case of the P2PKH script.
I know what the transaction hash preimage looks ...
- 1,029
5
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0
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76
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Which wallets are spending P2TR with SIGHASH_ALL?
I noticed there are quite a lot of transactions spending taproot key path inputs that use SIGHASH_ALL instead of SIGHASH_DEFAULT in signatures (around 20% in the last two weeks). Recall that ...
- 6,733
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334
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Can't verify Taproot signatures that use SIGHASH_ANYONECANPAY
I wrote a program that verifies signatures for Taproot transactions using the secp256k1 library. My program works perfectly for SIGHASH_ALL, SIGHASH_NONE and SIGHASH_SINGLE. But in February, we saw ...
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119
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SIGHASH_SINGLE with no corresponding output
Transaction 99fc1e5c753459808bac56435b3d45f2fcf0dd73016ea14460d63e9ddf353714 is an interesting example.
This transaction has 5 inputs and 1 output. All of the input scripts include 1 public key and 1 ...
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340
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What is SIGHASH_ANYPREVOUTANYSCRIPT?
BIP 118 describes SIGHASH_ANYPREVOUT, but also mentions SIGHASH_ANYPREVOUTANYSCRIPT. What is the difference, and why is the later sighash flag needed?
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Do you sign only the previous output of transaction?
I need to confirm that I understand how transactions work in the Bitcoin network. Ok, so:
Alice is a network node. Alice wants to send bitcoins to someone in the network. Alice is creating a ...
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1
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52
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Is it possible to reference an input outpoint more than once in a transaction?
For example, could you have the following transaction:
A --> B
A --> C
Where A is an input txid and index, and B and C are outputs? The reason I'm asking is because I believe with SIGHASH_SINGLE ...
- 779
1
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1
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318
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What goes in the tx hash preimage when signing with 0x83 (SINGLE|ANYONECANPAY)?
I have script to create a P2WPKH to P2WPKH transaction (1 input, 1 output) and sign it with the sighash type 0x01 SIGHASH_ALL.
Which fields would I need to change in the tx digest preimage to turn ...
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answer
988
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Do we still need SIGHASH_NOINPUT for Lightning Network?
In the original Lightning whitepaper, Joseph Poon advocates using SIGHASH_NOINPUT so that we can create the first commitment transaction which references the funding transaction txid without actually ...
- 7,348
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1
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125
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Is SIGHASH_NONE encompassing of other signature types?
Say I am building a transaction in private:
Input 1 is signed with SIGHASH_SINGLE ( | SIGHASH_ANYONECANPAY)
Input 2 is signed with SIGHASH_NONE | SIGHASH_ANYONECANPAY
SIGHASH_NONE implies that ...
- 243
0
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1
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255
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How to generate the digest from a raw bitcoin transaction for verifying signature of specific input?
I'm writing a stand alone process that needs to verify that a known UTXO is part of a new transaction with a valid signature.
Inputs [ UTXO, raw transaction, input_number ]
How do to I verify the ...
- 173
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1
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How was FORKID used in Bitcoin Cash at the original fork point and in all upgrades since?
References:
https://github.com/bitcoincashorg/bitcoincash.org/blob/master/spec/replay-protected-sighash.md
https://github.com/bitcoincashorg/bitcoincash.org/blob/master/spec/2018-nov-upgrade.md
It ...
- 4,992
2
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1
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237
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For a transaction with a single input and output, is there a difference between SIGHASH_ALL and SIGHASH_SINGLE|SIGHASH_ANYONECANPAY
I have an signing implementation that already works for SIGHASH_ALL, and I'm trying to also support SIGHASH_SINGLE|SIGHASH_ANYONECANPAY.
I'm referencing https://en.bitcoin.it/wiki/OP_CHECKSIG for the ...
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311
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How to specify the right input and output to be signed for SIGHASH_SINGLE
For my understand, when building a new TX, need to produce a new scriptSig for the TX; and need add a sigHash code at the end of the TX. If the sighash type is SIGHASH_SINGLE, for a TX with multiple ...
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186
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SIGHASH_SINGLE vbuterin/pybitcointools
Checking the implementation of Buterin's bitcoin tools I've noticed something strange. According to the Bitcoin developers guide, sighash_single signs only the outputs that match the input where the ...
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332
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Why are SIGHASH flags signed as 4 bytes when only 1 byte is included in the transaction?
This article brought to my attention that SIGHASH flags are 4 bytes long when signed, but only the last byte is actually included in the transaction. Then OP_CHECKSIG adds 3 bytes 0x000000 back on ...
- 4,992
3
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1
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448
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I'm trying to create a new kind of escrow with bitcoin, not sure if it's possible
First off, I understand that the standard way to do escrow with bitcoin is a P2SH with a 2 of 3 multisig redeem script. I'd like to try and do escrow in the following way:
names of 3 parties involved:...
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366
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Using SIGHASH_NONE in P2SH address
I know that using SIGHASH_NONE in signatures is safe for a transaction only if at least one of the inputs is signed with SIGHASH_ALL, so that a miner can't change the outputs and reclaim the inputs.
...
9
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What SIGHASH flags does CoinJoin use?
What SIGHASH flags are used when constructing a CoinJoin transaction?
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