How do you find the signing message of a TxIn signature? [NOT a duplicate] [duplicate]
This question already has an answer here:
- How to redeem a basic Tx? 3 answers
So I'm trying to find m in s = (m + r * x) / k of a Bitcoin transaction input.
Taking a look at this transaction, I can pull out s and r from the ScriptSig of an individual input: 30 45 02 21 00c717169b0055cf66d79d4cc59d05ce220341efd80985fa30bbfa88e9b69ecfb0 <--- r 02 20 10dbe3a7e3bc3201df8a42081c869f981bdd9d3e465f5fc483eaafab82f1ce7c <--- s 01
I know x is the PrivateKey and k is the Ethereal PrivateKey. But I can't seem to figure out m. I know it's a double sha2 hash of some message that produces r and s, but where it comes from or how it's put together seems a mystery. I've spent days stepping through NBitcoin's source code but I'm pretty lost. What makes it confusing is a bunch of things (versions, prev out, script sigs, sequences, etc) are hashed for the transaction as a whole and for each input but it's all sort of jumbled together.
What would be great is if the hashed signing message was available somewhere as a property in the transaction input details.
Maybe another way to ask this question might be, "Just using blockchain.info, how can I gather all the data necessary to verify a Bitcoin transaction INPUT (Not transaction)? Which would be s, r, and m." I already got r and s covered.
Update This isn't exactly a duplicate of How to redeem a basic Tx? because my question is around finding the signing messages of each input of an existing transaction, preferably just using info found on Blockchain.info. That question is about building a raw transaction which ties back to the expressed confusion in my question. It seems like signature explanations are geared towards signing the transaction as a whole as opposed to each individual Input. I'm trying to find many (s, r, m) in a transaction that has many inputs.
https://ift.tt/2KhYd9C
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