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r/Bitcoin: mixing human and hardware entropy with a one-time passphrase and BIP85

reddit-bip85-passphrase-entropy-mix

https://www.reddit.com/r/Bitcoin/comments/1vizful/you_can_mix_human_entropy_with_hardware_wallet/

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  1. Earliest copy held Current
    seen · Captured here 3,281 chars
    Extracted text as captured 
    post: 1vizful
author: randbtcacct
created_utc: 1786204321
title: You can mix human entropy with hardware wallet entropy using a one time passphrase and BIP85
body:
First let your hardware create a new seed normally. Enable passphrase. Use the passphrase field to enter over 100 dice rolls or any other equivalent entropy and apply. Do not worry about remembering the passphrase. After passphrase is active select BIP85 seed and copy the new BIP85 seed. 

Only keep the final seed and throw out the dice rolls or passphrase info and original seed (only if empty). Your final seed will be created using hardware entropy in original seed and human entropy from the passphrase. If either make a mistake in entropy the entropy is still good and requires failures of both to fail. 

Works on hardware wallets that will support BIP85 after passphrase

comment: p2hoso7
parent: t3_1vizful
author: creative_usr_name
created_utc: 1786208485
edited: false
body:
Assumes the hardware wallet works correctly, which we recently found out is not always the case. 

comment: p2hy57v
parent: t1_p2hoso7
author: randbtcacct
created_utc: 1786211102
edited: false
body:
Correct. This just eliminates any entropy risk.

comment: p2i5ulw
parent: t3_1vizful
author: flutecop
created_utc: 1786213275
edited: false
body:
Would XORing two seeds together accomplish the same thing?

I was thinking of XORing three seeds together. A coldcard seed with added dice rolls on updated firmware; a pen and paper dice rolled seed; and a seedsigner seed with image based entropy.

comment: p2ia8ef
parent: t3_1vizful
author: slvbtc

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