From a36e1ebca139ab4b31e12f0bf84bfb99481528bb Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Rafael=20Korba=C5=A1?= Date: Tue, 27 Apr 2021 09:11:13 +0200 Subject: [PATCH] CIP-0003 clarify Trezor deviation at 24-word mnemonics (#76) --- CIP-0003/Icarus.md | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/CIP-0003/Icarus.md b/CIP-0003/Icarus.md index 74864afeaa..4550e1630d 100644 --- a/CIP-0003/Icarus.md +++ b/CIP-0003/Icarus.md @@ -74,6 +74,6 @@ function tweakBits(data) { When used < 24 words, the algorithm is the same as **Icarus** -When using 24 words, **TODO** +When using 24 words, due to incorrect removal of the [BIP-39](https://github.com/bitcoin/bips/blob/master/bip-0039.mediawiki#generating-the-mnemonic) entropy checksum bits (via integer division by 8, incorrectly assuming the entropy checksum is always less than 8 bits), the entropy bytes are passed into the `generateMasterKey()` function together with the checksum which for 24-word mnemonics happens to be 8 bits = 1 byte. This bug has been identified and documented in the following Trezor firmware pull request: https://github.com/trezor/trezor-firmware/pull/1388 *Note*: Trezor also allows users to set an additional [passphrase](https://wiki.trezor.io/Passphrase) that works exactly the same as Icarus passphrase