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Title: Modifying outputs before forwarding? Post by: DannyHamilton on December 07, 2012, 03:25:42 PM I'm sure I'm missing something simple and obvious, but as I look through the protocol I'm not seeing what keeps me from creating a client that modifies the tx_out of all transactions that it receives before relaying them.
The tx_in is already signed in the transaction, so I don't need the private key. All I need to do is change the address in the pk_script of tx_out to one that I have the primary key to before relaying it. What am I missing here? Title: Re: Modifying outputs before forwarding? Post by: casascius on December 07, 2012, 03:40:05 PM The signatures sign a hash of the whole transaction with blanks in place of the signatures (obviously, since the signatures aren't known before signing).
Changing a txout will change the hash and therefore require a different signature. Title: Re: Modifying outputs before forwarding? Post by: DannyHamilton on December 07, 2012, 03:42:48 PM The signatures sign a hash of the whole transaction with blanks in place of the signatures (obviously, since the signatures aren't known before signing). I knew it would be something simple and obvious, I just wasn't seeing it. Thanks.Changing a txout will change the hash and therefore require a different signature. |