Old txn formula - from to same address

BlackHatCoiner

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Farewell, Leo

Quote from: MikeJ_NpC on March 28, 2023, 07:39:10 AM

i just recall something along these lines of old txns prior to change addresses being mandated.

What you're asking in the OP is if somebody could work out the key from a reused address, as far as I understand; that's what it essentially is, a reused address (for no obvious reason).

If you meant the private key, then no. Nobody could work it out with just a transaction which empties an output to the same address. If you meant the public key, then every transaction reveals it, regardless of whether it reuses addresses or not.

MikeJ_NpC

member

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if you want to lie *cough*use your data; not mine.

Sorry guys i should of been more clear...
not talking about a reuse aspect nor do i want people to argue over the question... i just recall something along these lines of old txns prior to change addresses being mandated.

Correct me if i am wrong .. but if you send payments to yourself without a change address, wasnt it possible to have a leak sorta speak..
Not referring to the reused R value which is not present...

or something where you use the rsz to narrow down the results.. etc ...

o_e_l_e_o

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What a classic insane piece of franky1 rambling nonsense.

Quote from: ?? on ??

topic title is about OLD transactions
you saying about stuff after 2013.. becomes redundant

Reused k values are possible with any transaction since day 1 of bitcoin.

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and while you say that stuff pre 6979 is a risk

Nope, never said that.

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so its not as vulnerable as you think

I never said it was.

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one of the many great things satoshi done was leave funds on keys he used as it helps prove the security of even the most basic of transaction formats

I never said that old transactions were vulnerable.

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the old stuff is not a case of "rapidly have their coins stolen"

Nope, didn't say that either.

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so cool down on the "rapidly stolen" ability of things you dont understand

Maybe you should try reading what I wrote rather than just launching in to one of your usual diatribes arguing against random strawmen.

All that I stated was that if you reuse a k value, your coins will be stolen. This is a simple fact. I made no statement whatsoever regarding old transactions being vulnerable or anything pre-6979 being vulnerable. This is all nonsense you made up simply to argue against.

BlackHatCoiner

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Merit: 7340

Farewell, Leo

It is impossible to work out the private key of such transaction, unless k value is reused as said above. No matter how many times you use an address, you only reveal the public key and the respective signature.

Quote from: ?? on ??

firstly there is no point making a transaction to send all funds to the same address..

You might want to leave a message. So, you burn 0 coins with OP_RETURN and send the rest to the same address.

Quote from: ?? on ??

and while you say that stuff pre 6979 is a risk.. again satoshi has respends of same address and 14 years of opportunity.. no one has bruted his funds

Reusing k value is irrelevant to Satoshi's P2PK funds. Just because he didn't it doesn't mean you can't create such transaction.

o_e_l_e_o

legendary

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Quote from: MikeJ_NpC on March 27, 2023, 01:17:52 AM

So from 123abc ---> to 123abc ...
If you had 2 of these you would be able to pull the key from it from what i recall...

I assume, since you are talking about 2 or more transactions, you are referring to the situation where a wallet would reuse k values. If you have two transactions spending coins from the same address and therefore using the same private key, and these two transactions also use the same k value (and therefore have the same r value), then it is possible to calculate the private key for that address.

However, this situation is a well known vulnerability, and there is no current wallet software I am aware of which utilizes reused k values. If there was, all its users would fairly rapidly have their coins stolen. Most good wallets will generate the k value deterministically using RFC 6979, ensuring a different k value for each transaction.

hd49728

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Not your keys, not your coins!

Quote from: MikeJ_NpC on March 27, 2023, 01:17:52 AM

If you have a wallet where the txn is to the same address as the sender ... without any change address... what was the formula to be able to derive the key from it ?

So from 123abc ---> to 123abc ...
If you had 2 of these you would be able to pull the key from it from what i recall...

Derive the key from it, pull the key from it, what did you mean?

Do you want to derive a private key from a public address?

It is impossible because if it is possible, your bitcoin will be stolen, my bitcoin will be stolen and bitcoin will have zero value.

Mastering Bitcoin (Keys, Addresses - chapter 4)

https://github.com/bitcoinbook/bitcoinbook/raw/develop/images/mbc2_0401.png

Private Key > Public Key (By Elliptic Curve Multiplication) > Bitcoin Address (By Hash Function, One-way).

You can not go from Bitcoin Address > Public Key > Private Key.

MikeJ_NpC

member

Activity: 107

Merit: 10

if you want to lie *cough*use your data; not mine.

If you have a wallet where the txn is to the same address as the sender ... without any change address... what was the formula to be able to derive the key from it ?

So from 123abc ---> to 123abc ...
If you had 2 of these you would be able to pull the key from it from what i recall...

This really doesnt apply now since change addresses are used but if anyone knows the format i would appreciate it...

Thanks.

Topic: Old txn formula - from to same address (Read 155 times)