Title: Wallet with hidden key, plausible deniability - salting password with WIF key Post by: Michael_S on December 07, 2013, 07:08:59 PM This is a suggestion for a best practice key management technique for everybody, using tools available today!
At the end I am also suggesting a corresponding feature enhancement for clients/apps that support key control. The situation: You are printing a paper wallet and store it somewhere in your house or flat. The Problem: A thief may rob your paper wallet and steal your bitcoins, just the same way he could steal your gold treasure. A first solution today: You print an encrypted paper wallet (BIP38), see e.g. bitaddress.org, current version 2.6.5 (or later) But the Problem: The thief may hold a gun against your head and kindly ask you to disclose the password. Now the encryption is of little help for you, the only thing you could do is to say you forgot the password, but this may not seem plausible to the thief. The SOLUTION: Combine the concept of "paper wallet" with the concept of "my own password" and "brain wallet", as follows: 1.) You print out your paper wallet, with e.g. Private Key = "5MyPrivatePaperWaLLetKey" 2.) You are making up yourself a 1st (easy) dummy password, e.g. "MyFirstSimplePW" and create the following concatenated string "5MyPrivatePaperWaLLetKeyMyFirstSimplePW" 2b.) You use this as the input of the brainwallet tool (which just calculates priv key = SHA256(input). This gives you (after format conversion to WIF) the second private key "5MySecondPrivateKey" 3.) You are thinking of a 2nd (difficult) serious passphrase, e.g. "My_very-s3ri0UsP4s5PhRA5e" and create the following concatenated string "5MyPrivatePaperWaLLetKeyMy_very-s3ri0UsP4s5PhRA5e" 3b.) You use this as the input of the brainwallet tool. This gives you the third private key "5MyThirdReaLLySafePrivateKey" 4.1) You transfer a very small amount (e.g. 1% of your total BTC savings) to the Address of Key 1. 4.2) You transfer a bigger amount (maybe 10% of your total BTC savings) to the Address of Key 2. 4.3) You transfer the vast amount (e.g. 89% of your BTC savings) to the Address of Key 3. Note: Of course you print out at least two copies of this paper wallet and deposit them at very different places. With this best practice you now enjoy the following nice features:
Finally, the same scheme can also be applied to electronic wallets of course. One suggestion for bitcoin client developers: It might be nice and really useful to incorporate this in any bitcoin client that supports key control (coin control), i.e selection of the keys were to spend from:
Title: Re: Wallet with hidden key, plausible deniability - salting password with WIF key Post by: naphto on December 07, 2013, 07:38:02 PM Someone wanted to reply here:
https://bitcointalk.org/index.php?topic=361439.new#new Hi, I registered to reply to that post: https://bitcointalk.org/index.php?topic=361386.0 I would like to reply with a link to this bugtracker entry because it requests specifically what the thread emulates: https://github.com/bitcoin/bitcoin/issues/3212 Can someone post that link there for me, or allow me to do it myself? Thanks Title: Re: Wallet with hidden key, plausible deniability - salting password with WIF key Post by: TippingPoint on December 07, 2013, 07:39:09 PM Thank you for the ideas.
And there is no reason that a paper Bitcoin wallet has to always look like a paper Bitcoin wallet. https://bitcointalk.org/index.php?topic=327277.msg3535036#msg3535036 https://images.weserv.nl/?url=i43.tinypic.com/2i03bs5.png&fnr Title: Re: Wallet with hidden key, plausible deniability - salting password with WIF key Post by: virtualmaster on December 07, 2013, 08:35:06 PM Here is my advise:
https://bitcointalk.org/index.php?topic=359644.msg3853593#msg3853593 (https://bitcointalk.org/index.php?topic=359644.msg3853593#msg3853593) Title: Re: Wallet with hidden key, plausible deniability - salting password with WIF key Post by: Michael_S on December 07, 2013, 09:20:10 PM Thanks naphto / kgbxcbk, seems to be a similar idea indeed.
For the rest: Please do not dump everything that comes to your mind on "paperwallets" into this thread if it is otherwise unrelated to the OP (at least I do not see a relation). |