Message-ID: <54FBA72E.4040308@gk2.sk>
Date: Sun, 08 Mar 2015 02:34:38 +0100
From: Pavol Rusnak <stick@gk2.sk>
User-Agent: Mozilla/5.0 (X11; Linux x86_64;
	rv:31.0) Gecko/20100101 Thunderbird/31.4.0
MIME-Version: 1.0
To: Mem Wallet <memwallet.info@gmail.com>, 
	bitcoin-development@lists.sourceforge.net
References: <CAKzHBKnh+yzTwXkZXmezRaOkTTnUO4Z1dJnvKjYGnZBKoNQNEQ@mail.gmail.com>
In-Reply-To: <CAKzHBKnh+yzTwXkZXmezRaOkTTnUO4Z1dJnvKjYGnZBKoNQNEQ@mail.gmail.com>
Content-Type: text/plain; charset=windows-1252
Content-Transfer-Encoding: 8bit
Subject: Re: [Bitcoin-development] bip44 GPG identities - POC demo
Precedence: list

On 07/03/15 16:53, Mem Wallet wrote:
> this allows a user to manage a GPG identity for encryption
> and signing with zero bytes of permanent storage. (on tails for example)

Hi!

As an author of BIP44 I don't think that you should use BIP44 for this
and a new BIP number should be allocated. To me it does not make much
sense to create GPG key hierarchy per Bitcoin account, but rather create
a GPG key hierarchy per device/master seed.

I am currently in process of implementing a SignIdentity message for
TREZOR, which will be used for HTTPS/SSH/etc. logins.

See PoC here:
https://github.com/trezor/trezor-emu/commit/9f612c286cc7b8268ebaec4a36757e1c19548717

The idea is to derive the BIP32 path from HTTPS/SSH URI (by hashing it
and use m/46'/a'/b'/c'/d' where a,b,c,d are first 4*32 bits of the hash)
and use that to derive the private key. This scheme might work for GPG
keys (just use gpg://user@host.com for the URI) as well.

-- 
Best Regards / S pozdravom,

Pavol Rusnak <stick@gk2.sk>