use std::{collections::HashMap, io::Write, str::FromStr};
use rand::{rngs::OsRng, CryptoRng, Rng};
use sha2::{Digest, Sha256};
use thiserror::Error;
#[allow(unused)]
const MIN_NB_WORDS: usize = 12;
const MAX_NB_WORDS: usize = 24;
#[derive(Debug, Error)]
pub enum Bip39Error {
#[error("Invalid entropy length {0}, expect entropy len [16,64] and a multiple of 4")]
InvalidEntropyLength(usize),
#[error("Invalid num of mnemonic words {0}, should be 12,15,18,21 or 24")]
MnemonicNumOfWords(usize),
#[error("Invalid mnemonic word {0}, not found in dictionary")]
MnemonicWord(String),
#[error("mnemonic checksum mismatch")]
Checksum,
}
#[derive(Debug, Clone)]
pub struct Dictionary {
word_list: Vec<String>,
indexer: HashMap<String, usize>,
}
impl Dictionary {
pub fn new(word_list: Vec<String>) -> Self {
let mut indexer = HashMap::<String, usize>::new();
for (index, word) in word_list.iter().enumerate() {
indexer.insert(word.to_owned(), index);
}
Self { word_list, indexer }
}
}
impl FromStr for Dictionary {
type Err = serde_json::Error;
fn from_str(s: &str) -> Result<Self, Self::Err> {
Ok(Self::new(serde_json::from_str(s)?))
}
}
#[derive(Debug, Clone)]
pub struct Bip39Generator {
dic: Dictionary,
}
impl Bip39Generator {
pub fn new(dic: Dictionary) -> Self {
Self { dic }
}
pub fn gen_mnemonic<const LEN: usize>(&self) -> Result<String, Bip39Error> {
self.gen_mnemonic_with::<rand::rngs::OsRng, LEN>(&mut OsRng)
}
pub fn gen_mnemonic_with<EG, const LEN: usize>(
&self,
rng: &mut EG,
) -> Result<String, Bip39Error>
where
EG: CryptoRng + Rng,
{
if LEN < 16 || LEN > 64 || LEN % 4 != 0 {
return Err(Bip39Error::InvalidEntropyLength(LEN));
}
let mut entropy = [0; LEN];
rng.fill_bytes(&mut entropy);
self.mnemonic_from_entropy(&entropy)
}
pub fn mnemonic_from_entropy(&self, entropy: &[u8]) -> Result<String, Bip39Error> {
const MAX_ENTROPY_BITS: usize = 256;
const MIN_ENTROPY_BITS: usize = 128;
const MAX_CHECKSUM_BITS: usize = 8;
let nb_bytes = entropy.len();
let nb_bits = nb_bytes * 8;
if nb_bits % 32 != 0 {
return Err(Bip39Error::InvalidEntropyLength(nb_bytes));
}
if nb_bits < MIN_ENTROPY_BITS || nb_bits > MAX_ENTROPY_BITS {
return Err(Bip39Error::InvalidEntropyLength(nb_bytes));
}
let mut hasher = Sha256::new();
hasher.write(&entropy).expect("Sha256 entropy");
let check = hasher.finalize();
let mut bits = [false; MAX_ENTROPY_BITS + MAX_CHECKSUM_BITS];
for i in 0..nb_bytes {
for j in 0..8 {
bits[i * 8 + j] = (entropy[i] & (1 << (7 - j))) > 0;
}
}
for i in 0..nb_bytes / 4 {
bits[8 * nb_bytes + i] = (check[i / 8] & (1 << (7 - (i % 8)))) > 0;
}
let mut words = vec![];
let nb_words = nb_bytes * 3 / 4;
for i in 0..nb_words {
let mut idx = 0;
for j in 0..11 {
if bits[i * 11 + j] {
idx += 1 << (10 - j);
}
}
words.push(self.dic.word_list[idx].clone());
}
Ok(words.join(" "))
}
pub fn mnemonic_check<S>(&self, mnemonic: S) -> Result<(), Bip39Error>
where
S: AsRef<str>,
{
let mnemonic = mnemonic.as_ref();
let words = mnemonic.split(" ").collect::<Vec<_>>();
let num_of_words = words.len();
if num_of_words % 3 != 0 || num_of_words < 12 || num_of_words > 24 {
return Err(Bip39Error::MnemonicNumOfWords(num_of_words));
}
let mut bits = [false; MAX_NB_WORDS * 11];
for (i, word) in words.iter().enumerate() {
if let Some(index) = self.dic.indexer.get(*word) {
for j in 0..11 {
bits[i * 11 + j] = index >> (10 - j) & 1 == 1;
}
} else {
return Err(Bip39Error::MnemonicWord(word.to_string()));
}
}
let mut entropy = [0u8; MAX_NB_WORDS / 3 * 4];
let nb_bytes_entropy = num_of_words / 3 * 4;
for i in 0..nb_bytes_entropy {
for j in 0..8 {
if bits[i * 8 + j] {
entropy[i] += 1 << (7 - j);
}
}
}
let mut hasher = Sha256::new();
hasher.write(&entropy[0..nb_bytes_entropy]).expect("");
let check = hasher.finalize();
for i in 0..nb_bytes_entropy / 4 {
if bits[8 * nb_bytes_entropy + i] != ((check[i / 8] & (1 << (7 - (i % 8)))) > 0) {
return Err(Bip39Error::Checksum);
}
}
Ok(())
}
}
pub mod languages {
use super::Dictionary;
pub fn en_us() -> Dictionary {
include_str!("bip39/en_us.json")
.parse()
.expect("Load dictionary")
}
}
#[cfg(test)]
mod tests {
use ethers_primitives::FromEtherHex;
use super::{languages::en_us, Bip39Generator};
#[test]
fn test_checksum() {
let _ = pretty_env_logger::try_init();
let gen = Bip39Generator::new(en_us());
let mnemonic = gen.gen_mnemonic::<16>().expect("Generate mnemonic");
log::debug!("mnemonic: \r\n {}", mnemonic);
gen.mnemonic_check(mnemonic).expect("Mnemonic check");
}
#[test]
fn test_with_entropy() {
let entropy = Vec::<u8>::from_eth_hex("0x7b6228a8803ad9883bca8b46c55a2c3f").unwrap();
let gen = Bip39Generator::new(en_us());
let mnemonic = gen.mnemonic_from_entropy(&entropy).expect("From entropy");
assert_eq!(
mnemonic,
"kiwi bacon clay about pulse series upset fabric egg client mention lazy"
);
}
#[test]
fn teset_vectors() {
let test_vectors = [
(
"00000000000000000000000000000000",
"abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon about",
"c55257c360c07c72029aebc1b53c05ed0362ada38ead3e3e9efa3708e53495531f09a6987599d18264c1e1c92f2cf141630c7a3c4ab7c81b2f001698e7463b04",
),
(
"7f7f7f7f7f7f7f7f7f7f7f7f7f7f7f7f",
"legal winner thank year wave sausage worth useful legal winner thank yellow",
"2e8905819b8723fe2c1d161860e5ee1830318dbf49a83bd451cfb8440c28bd6fa457fe1296106559a3c80937a1c1069be3a3a5bd381ee6260e8d9739fce1f607",
),
(
"80808080808080808080808080808080",
"letter advice cage absurd amount doctor acoustic avoid letter advice cage above",
"d71de856f81a8acc65e6fc851a38d4d7ec216fd0796d0a6827a3ad6ed5511a30fa280f12eb2e47ed2ac03b5c462a0358d18d69fe4f985ec81778c1b370b652a8",
),
(
"ffffffffffffffffffffffffffffffff",
"zoo zoo zoo zoo zoo zoo zoo zoo zoo zoo zoo wrong",
"ac27495480225222079d7be181583751e86f571027b0497b5b5d11218e0a8a13332572917f0f8e5a589620c6f15b11c61dee327651a14c34e18231052e48c069",
),
(
"000000000000000000000000000000000000000000000000",
"abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon agent",
"035895f2f481b1b0f01fcf8c289c794660b289981a78f8106447707fdd9666ca06da5a9a565181599b79f53b844d8a71dd9f439c52a3d7b3e8a79c906ac845fa",
),
(
"7f7f7f7f7f7f7f7f7f7f7f7f7f7f7f7f7f7f7f7f7f7f7f7f",
"legal winner thank year wave sausage worth useful legal winner thank year wave sausage worth useful legal will",
"f2b94508732bcbacbcc020faefecfc89feafa6649a5491b8c952cede496c214a0c7b3c392d168748f2d4a612bada0753b52a1c7ac53c1e93abd5c6320b9e95dd",
),
(
"808080808080808080808080808080808080808080808080",
"letter advice cage absurd amount doctor acoustic avoid letter advice cage absurd amount doctor acoustic avoid letter always",
"107d7c02a5aa6f38c58083ff74f04c607c2d2c0ecc55501dadd72d025b751bc27fe913ffb796f841c49b1d33b610cf0e91d3aa239027f5e99fe4ce9e5088cd65",
),
(
"ffffffffffffffffffffffffffffffffffffffffffffffff",
"zoo zoo zoo zoo zoo zoo zoo zoo zoo zoo zoo zoo zoo zoo zoo zoo zoo when",
"0cd6e5d827bb62eb8fc1e262254223817fd068a74b5b449cc2f667c3f1f985a76379b43348d952e2265b4cd129090758b3e3c2c49103b5051aac2eaeb890a528",
),
(
"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",
),
(
"7f7f7f7f7f7f7f7f7f7f7f7f7f7f7f7f7f7f7f7f7f7f7f7f7f7f7f7f7f7f7f7f",
"legal winner thank year wave sausage worth useful legal winner thank year wave sausage worth useful legal winner thank year wave sausage worth title",
"bc09fca1804f7e69da93c2f2028eb238c227f2e9dda30cd63699232578480a4021b146ad717fbb7e451ce9eb835f43620bf5c514db0f8add49f5d121449d3e87",
),
(
"8080808080808080808080808080808080808080808080808080808080808080",
"letter advice cage absurd amount doctor acoustic avoid letter advice cage absurd amount doctor acoustic avoid letter advice cage absurd amount doctor acoustic bless",
"c0c519bd0e91a2ed54357d9d1ebef6f5af218a153624cf4f2da911a0ed8f7a09e2ef61af0aca007096df430022f7a2b6fb91661a9589097069720d015e4e982f",
),
(
"ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff",
"zoo zoo zoo zoo zoo zoo zoo zoo zoo zoo zoo zoo zoo zoo zoo zoo zoo zoo zoo zoo zoo zoo zoo vote",
"dd48c104698c30cfe2b6142103248622fb7bb0ff692eebb00089b32d22484e1613912f0a5b694407be899ffd31ed3992c456cdf60f5d4564b8ba3f05a69890ad",
),
(
"9e885d952ad362caeb4efe34a8e91bd2",
"ozone drill grab fiber curtain grace pudding thank cruise elder eight picnic",
"274ddc525802f7c828d8ef7ddbcdc5304e87ac3535913611fbbfa986d0c9e5476c91689f9c8a54fd55bd38606aa6a8595ad213d4c9c9f9aca3fb217069a41028",
),
(
"6610b25967cdcca9d59875f5cb50b0ea75433311869e930b",
"gravity machine north sort system female filter attitude volume fold club stay feature office ecology stable narrow fog",
"628c3827a8823298ee685db84f55caa34b5cc195a778e52d45f59bcf75aba68e4d7590e101dc414bc1bbd5737666fbbef35d1f1903953b66624f910feef245ac",
),
(
"68a79eaca2324873eacc50cb9c6eca8cc68ea5d936f98787c60c7ebc74e6ce7c",
"hamster diagram private dutch cause delay private meat slide toddler razor book happy fancy gospel tennis maple dilemma loan word shrug inflict delay length",
"64c87cde7e12ecf6704ab95bb1408bef047c22db4cc7491c4271d170a1b213d20b385bc1588d9c7b38f1b39d415665b8a9030c9ec653d75e65f847d8fc1fc440",
),
(
"c0ba5a8e914111210f2bd131f3d5e08d",
"scheme spot photo card baby mountain device kick cradle pact join borrow",
"ea725895aaae8d4c1cf682c1bfd2d358d52ed9f0f0591131b559e2724bb234fca05aa9c02c57407e04ee9dc3b454aa63fbff483a8b11de949624b9f1831a9612",
),
(
"6d9be1ee6ebd27a258115aad99b7317b9c8d28b6d76431c3",
"horn tenant knee talent sponsor spell gate clip pulse soap slush warm silver nephew swap uncle crack brave",
"fd579828af3da1d32544ce4db5c73d53fc8acc4ddb1e3b251a31179cdb71e853c56d2fcb11aed39898ce6c34b10b5382772db8796e52837b54468aeb312cfc3d",
),
(
"9f6a2878b2520799a44ef18bc7df394e7061a224d2c33cd015b157d746869863",
"panda eyebrow bullet gorilla call smoke muffin taste mesh discover soft ostrich alcohol speed nation flash devote level hobby quick inner drive ghost inside",
"72be8e052fc4919d2adf28d5306b5474b0069df35b02303de8c1729c9538dbb6fc2d731d5f832193cd9fb6aeecbc469594a70e3dd50811b5067f3b88b28c3e8d",
),
(
"23db8160a31d3e0dca3688ed941adbf3",
"cat swing flag economy stadium alone churn speed unique patch report train",
"deb5f45449e615feff5640f2e49f933ff51895de3b4381832b3139941c57b59205a42480c52175b6efcffaa58a2503887c1e8b363a707256bdd2b587b46541f5",
),
(
"8197a4a47f0425faeaa69deebc05ca29c0a5b5cc76ceacc0",
"light rule cinnamon wrap drastic word pride squirrel upgrade then income fatal apart sustain crack supply proud access",
"4cbdff1ca2db800fd61cae72a57475fdc6bab03e441fd63f96dabd1f183ef5b782925f00105f318309a7e9c3ea6967c7801e46c8a58082674c860a37b93eda02",
),
(
"066dca1a2bb7e8a1db2832148ce9933eea0f3ac9548d793112d9a95c9407efad",
"all hour make first leader extend hole alien behind guard gospel lava path output census museum junior mass reopen famous sing advance salt reform",
"26e975ec644423f4a4c4f4215ef09b4bd7ef924e85d1d17c4cf3f136c2863cf6df0a475045652c57eb5fb41513ca2a2d67722b77e954b4b3fc11f7590449191d",
),
(
"f30f8c1da665478f49b001d94c5fc452",
"vessel ladder alter error federal sibling chat ability sun glass valve picture",
"2aaa9242daafcee6aa9d7269f17d4efe271e1b9a529178d7dc139cd18747090bf9d60295d0ce74309a78852a9caadf0af48aae1c6253839624076224374bc63f",
),
(
"c10ec20dc3cd9f652c7fac2f1230f7a3c828389a14392f05",
"scissors invite lock maple supreme raw rapid void congress muscle digital elegant little brisk hair mango congress clump",
"7b4a10be9d98e6cba265566db7f136718e1398c71cb581e1b2f464cac1ceedf4f3e274dc270003c670ad8d02c4558b2f8e39edea2775c9e232c7cb798b069e88",
),
(
"f585c11aec520db57dd353c69554b21a89b20fb0650966fa0a9d6f74fd989d8f",
"void come effort suffer camp survey warrior heavy shoot primary clutch crush open amazing screen patrol group space point ten exist slush involve unfold",
"01f5bced59dec48e362f2c45b5de68b9fd6c92c6634f44d6d40aab69056506f0e35524a518034ddc1192e1dacd32c1ed3eaa3c3b131c88ed8e7e54c49a5d0998",
)
];
let gen = Bip39Generator::new(en_us());
for vector in &test_vectors {
let entropy = Vec::<u8>::from_eth_hex(&vector.0).unwrap();
let mnemonic_expected = vector.1;
let mnemonic = gen.mnemonic_from_entropy(&entropy).expect("From entropy");
assert_eq!(mnemonic, mnemonic_expected);
}
}
}