From: Jonas Schnelli <dev@jonasschnelli.ch>
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Date: Fri, 29 Sep 2017 21:49:52 -0700
References: <e43c6e06-0bdc-360e-eb5c-a3726e4f0fc8@osc.co.cr>
To: Dan Libby <dan@osc.co.cr>,
	Bitcoin Protocol Discussion <bitcoin-dev@lists.linuxfoundation.org>
In-Reply-To: <e43c6e06-0bdc-360e-eb5c-a3726e4f0fc8@osc.co.cr>
Message-Id: <96328209-9249-44BC-957A-4EF8DE014E2D@jonasschnelli.ch>
Subject: Re: [bitcoin-dev] Paper Wallet support in bitcoin-core
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> Hi,
>=20
> I'm writing to suggest and discuss the addition of paper wallet
> functionality in bitcoin-core software, starting with a single new RPC
> call: genExternalAddress [type].
>=20

AFAIK, client implementations such as your proposal are off-topic for =
this ML.
Better use bitcoin-core-dev (ML or IRC) or Github (bitcoin/bitcoin) for =
such proposals.


> On 09/29/2017 02:03 PM, Luke Dashjr wrote:
> Paper wallets are a safety hazard, insecure, and generally not =
advisable.
>=20

I have to agree with Luke.
And I would also extend those concerns to BIP39 plaintext paper backups.

IMO, private keys should be generated and used (signing) on a trusted, =
minimal and offline hardware/os. They should never leave the device over =
the channel used for the signing I/O. Users should have no way to view =
or export the private keys (expect for the seed backup). Backups should =
be encrypted (whoever finds the paper backup should need a second factor =
to decrypt) and the restore process should be footgun-safe (especially =
the lost-passphrase deadlock).


/jonas

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