-
Notifications
You must be signed in to change notification settings - Fork 10
Commit
This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
Begin work on implementing BIP39 algorithm.
- Loading branch information
Showing
6 changed files
with
254 additions
and
10 deletions.
There are no files selected for viewing
Some generated files are not rendered by default. Learn more about how customized files appear on GitHub.
Oops, something went wrong.
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -0,0 +1,81 @@ | ||
| use sha2::{Digest, Sha256}; | ||
|
|
||
| /// Calculate BIP39 checksum (CS) bits given entropy bits. | ||
| fn calculate_cs_bits(ent: &[u8]) -> u8 { | ||
| let mut hasher = Sha256::new(); | ||
| hasher.update(ent); | ||
| let hash = hasher.finalize(); | ||
| let shift = match ent.len() { | ||
| // 128 bits of entropy (16 bytes) needs 4 bits of checksum | ||
| 16 => 4usize, | ||
| // 160 bits of entropy (20 bytes) needs 5 bits of checksum | ||
| 20 => 3, | ||
| // 192 bits of entropy (24 bytes) needs 6 bits of checksum | ||
| 24 => 2, | ||
| // 224 bits of entropy (28 bytes) needs 7 bits of checksum | ||
| 28 => 1, | ||
| // 256 bits of entropy (32 bytes) needs 8 bits of checksum | ||
| 32 => 0, | ||
| // No other number of bits of entropy aside from the above is supported by BIP39. | ||
| // And since this function is internal to our program, and we only intend to call it | ||
| // with the supported number of bits of entropy, there really isn't much point in going | ||
| // through the extra motions of returning an error since it would mean we have a fatal | ||
| // (unrecoverable) error in the coding of our program anyway. So we may as well panic | ||
| // via `unreachable!()` instead of returning details about the error. | ||
| _ => unreachable!(), | ||
| }; | ||
| hash[0] >> shift | ||
| } | ||
|
|
||
| #[cfg(test)] | ||
| mod test { | ||
| use crate::bip39_algorithm::calculate_cs_bits; | ||
| use test_case::test_case; | ||
|
|
||
| // From <https://github.com/trezor/python-mnemonic/blob/b57a5ad77a981e743f4167ab2f7927a55c1e82a8/vectors.json#L3-L8>: | ||
| // | ||
| // ```json | ||
| // [ | ||
| // "00000000000000000000000000000000", | ||
| // "abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon about", | ||
| // "c55257c360c07c72029aebc1b53c05ed0362ada38ead3e3e9efa3708e53495531f09a6987599d18264c1e1c92f2cf141630c7a3c4ab7c81b2f001698e7463b04", | ||
| // "xprv9s21ZrQH143K3h3fDYiay8mocZ3afhfULfb5GX8kCBdno77K4HiA15Tg23wpbeF1pLfs1c5SPmYHrEpTuuRhxMwvKDwqdKiGJS9XFKzUsAF" | ||
| // ], | ||
| // ``` | ||
| // | ||
| // - 128 bits of "entropy" (all zero in this case). | ||
| // - The 12th word in the mnemonic sentence is the 4th word (index 3) in the BIP39 English wordlist. | ||
| #[test_case(&[0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0], 3; "128 bits of all zeros")] | ||
| // From <https://github.com/trezor/python-mnemonic/blob/b57a5ad77a981e743f4167ab2f7927a55c1e82a8/vectors.json#L27-L32>: | ||
| // | ||
| // ```json | ||
| // [ | ||
| // "000000000000000000000000000000000000000000000000", | ||
| // "abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon agent", | ||
| // "035895f2f481b1b0f01fcf8c289c794660b289981a78f8106447707fdd9666ca06da5a9a565181599b79f53b844d8a71dd9f439c52a3d7b3e8a79c906ac845fa", | ||
| // "xprv9s21ZrQH143K3mEDrypcZ2usWqFgzKB6jBBx9B6GfC7fu26X6hPRzVjzkqkPvDqp6g5eypdk6cyhGnBngbjeHTe4LsuLG1cCmKJka5SMkmU" | ||
| // ], | ||
| // ``` | ||
| // | ||
| // - 192 bits of "entropy" (all zero in this case). | ||
| // - The 18th word in the mnemonic sentence is the 40th word (index 39) in the BIP39 English wordlist. | ||
| #[test_case(&[0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0], 39; "192 bits of all zeros")] | ||
| // From <https://github.com/trezor/python-mnemonic/blob/b57a5ad77a981e743f4167ab2f7927a55c1e82a8/vectors.json#L51-L56>: | ||
| // | ||
| // ```json | ||
| // [ | ||
| // "0000000000000000000000000000000000000000000000000000000000000000", | ||
| // "abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon art", | ||
| // "bda85446c68413707090a52022edd26a1c9462295029f2e60cd7c4f2bbd3097170af7a4d73245cafa9c3cca8d561a7c3de6f5d4a10be8ed2a5e608d68f92fcc8", | ||
| // "xprv9s21ZrQH143K32qBagUJAMU2LsHg3ka7jqMcV98Y7gVeVyNStwYS3U7yVVoDZ4btbRNf4h6ibWpY22iRmXq35qgLs79f312g2kj5539ebPM" | ||
| // ], | ||
| // ``` | ||
| // | ||
| // - 256 bits of "entropy" (all zero in this case). | ||
| // - The 24th word in the mnemonic sentence is the 103rd word (index 102) in the BIP39 English wordlist. | ||
| #[test_case(&[0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0], 102; "256 bits of all zeros")] | ||
| fn calculates_cs_bits_correctly(ent: &[u8], cs_expected: u8) { | ||
| let cs_actual = calculate_cs_bits(ent); | ||
| assert_eq!(cs_expected, cs_actual); | ||
| } | ||
| } |
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters