WASM: add support for mnemonics

ironfish-rust-nodejs/src/lib.rs

@@ -109,7 +109,7 @@ pub fn spending_key_to_words(private_key: String, language_code: LanguageCode) -
 
 #[napi]
 pub fn words_to_spending_key(words: String, language_code: LanguageCode) -> Result<String> {
-    let key = SaplingKey::from_words(words, language_code.into()).map_err(to_napi_err)?;
+    let key = SaplingKey::from_words(&words, language_code.into()).map_err(to_napi_err)?;
     Ok(key.hex_spending_key())
 }
 

ironfish-rust-wasm/Cargo.toml

@@ -29,6 +29,7 @@ ironfish-jubjub = "0.1.0"
 ironfish_zkp = { version = "0.2.0", path = "../ironfish-zkp" }
 rand = "0.8.5"
 rayon = { version = "1.8.1", features = ["web_spin_lock"] } # need to explicitly enable the `web_spin_lock` in order to run in a browser
+tiny-bip39 = "1.0"
 wasm-bindgen = "0.2.95"
 
 [dev-dependencies]

ironfish-rust-wasm/src/keys/mnemonics.rs

@@ -0,0 +1,76 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
+
+use crate::errors::IronfishError;
+use ironfish::errors::IronfishErrorKind;
+use wasm_bindgen::prelude::*;
+
+#[wasm_bindgen]
+#[derive(Copy, Clone, PartialEq, Eq, Debug)]
+pub enum Language {
+    English,
+    ChineseSimplified,
+    ChineseTraditional,
+    French,
+    Italian,
+    Japanese,
+    Korean,
+    Spanish,
+}
+
+impl From<bip39::Language> for Language {
+    fn from(x: bip39::Language) -> Self {
+        match x {
+            bip39::Language::English => Self::English,
+            bip39::Language::ChineseSimplified => Self::ChineseSimplified,
+            bip39::Language::ChineseTraditional => Self::ChineseTraditional,
+            bip39::Language::French => Self::French,
+            bip39::Language::Italian => Self::Italian,
+            bip39::Language::Japanese => Self::Japanese,
+            bip39::Language::Korean => Self::Korean,
+            bip39::Language::Spanish => Self::Spanish,
+        }
+    }
+}
+
+impl From<Language> for bip39::Language {
+    fn from(x: Language) -> Self {
+        match x {
+            Language::English => Self::English,
+            Language::ChineseSimplified => Self::ChineseSimplified,
+            Language::ChineseTraditional => Self::ChineseTraditional,
+            Language::French => Self::French,
+            Language::Italian => Self::Italian,
+            Language::Japanese => Self::Japanese,
+            Language::Korean => Self::Korean,
+            Language::Spanish => Self::Spanish,
+        }
+    }
+}
+
+#[wasm_bindgen]
+impl Language {
+    #[wasm_bindgen(constructor)]
+    pub fn from_language_code(code: &str) -> Result<Self, IronfishError> {
+        bip39::Language::from_language_code(code)
+            .map(Self::from)
+            .ok_or_else(|| IronfishErrorKind::InvalidLanguageEncoding.into())
+    }
+
+    #[wasm_bindgen(getter, js_name = "languageCode")]
+    pub fn language_code(self) -> String {
+        // For some reason, `bip39` does not provide a way to convert a `Language` back to string.
+        match self {
+            Self::English => "en",
+            Self::ChineseSimplified => "zh-hans",
+            Self::ChineseTraditional => "zh-hant",
+            Self::French => "fr",
+            Self::Italian => "it",
+            Self::Japanese => "ja",
+            Self::Korean => "ko",
+            Self::Spanish => "es",
+        }
+        .to_owned()
+    }
+}

ironfish-rust-wasm/src/keys/mod.rs

@@ -2,11 +2,13 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
 
+mod mnemonics;
 mod proof_generation_key;
 mod public_address;
 mod sapling_key;
 mod view_keys;
 
+pub use mnemonics::Language;
 pub use proof_generation_key::ProofGenerationKey;
 pub use public_address::PublicAddress;
 pub use sapling_key::SaplingKey;

ironfish-rust-wasm/src/keys/sapling_key.rs

@@ -4,7 +4,9 @@
 
 use crate::{
     errors::IronfishError,
-    keys::{IncomingViewKey, OutgoingViewKey, ProofGenerationKey, PublicAddress, ViewKey},
+    keys::{
+        IncomingViewKey, Language, OutgoingViewKey, ProofGenerationKey, PublicAddress, ViewKey,
+    },
     wasm_bindgen_wrapper,
 };
 use wasm_bindgen::prelude::*;
@@ -45,7 +47,21 @@ impl SaplingKey {
         self.0.hex_spending_key()
     }
 
-    // TODO: to/fromWords
+    #[wasm_bindgen(js_name = fromWords)]
+    pub fn from_words(lang: Language, words: &str) -> Result<Self, IronfishError> {
+        ironfish::keys::SaplingKey::from_words(words, lang.into())
+            .map(|key| key.into())
+            .map_err(|err| err.into())
+    }
+
+    #[wasm_bindgen(js_name = toWords)]
+    pub fn to_words(&self, lang: Language) -> String {
+        self.0
+            .to_words(lang.into())
+            .expect("conversion to words failed")
+            .phrase()
+            .to_string()
+    }
 
     #[wasm_bindgen(getter, js_name = publicAddress)]
     pub fn public_address(&self) -> PublicAddress {
@@ -80,7 +96,9 @@ impl SaplingKey {
 
 #[cfg(test)]
 mod tests {
-    use crate::keys::{IncomingViewKey, OutgoingViewKey, ProofGenerationKey, SaplingKey, ViewKey};
+    use crate::keys::{
+        IncomingViewKey, Language, OutgoingViewKey, ProofGenerationKey, SaplingKey, ViewKey,
+    };
     use wasm_bindgen_test::wasm_bindgen_test;
 
     macro_rules! assert_serde_ok {
@@ -102,4 +120,15 @@ mod tests {
         assert_serde_ok!(ViewKey, key.view_key());
         assert_serde_ok!(ProofGenerationKey, key.proof_generation_key());
     }
+
+    #[test]
+    #[wasm_bindgen_test]
+    fn from_to_words() {
+        let key = SaplingKey::random();
+        let lang = Language::English;
+        assert_eq!(
+            &key,
+            &SaplingKey::from_words(lang, key.to_words(lang).as_ref()).unwrap()
+        );
+    }
 }

ironfish-rust-wasm/src/keys/view_keys.rs

@@ -4,7 +4,7 @@
 
 use crate::{
     errors::IronfishError,
-    keys::PublicAddress,
+    keys::{Language, PublicAddress},
     primitives::{Fr, PublicKey},
     wasm_bindgen_wrapper,
 };
@@ -39,7 +39,21 @@ impl IncomingViewKey {
         self.0.hex_key()
     }
 
-    // TODO: to/fromWords
+    #[wasm_bindgen(js_name = fromWords)]
+    pub fn from_words(lang: Language, words: &str) -> Result<Self, IronfishError> {
+        ironfish::keys::IncomingViewKey::from_words(lang.language_code().as_ref(), words)
+            .map(|key| key.into())
+            .map_err(|err| err.into())
+    }
+
+    #[wasm_bindgen(js_name = toWords)]
+    pub fn to_words(&self, lang: Language) -> String {
+        // `words_key()` may fail only if the language code is invalid, but here we're accepting
+        // `Language`, not an arbitrary input, so the language code is guaranteed to be valid.
+        self.0
+            .words_key(lang.language_code().as_ref())
+            .expect("conversion to words failed")
+    }
 
     #[wasm_bindgen(getter, js_name = publicAddress)]
     pub fn public_address(&self) -> PublicAddress {
@@ -74,7 +88,21 @@ impl OutgoingViewKey {
         self.0.hex_key()
     }
 
-    // TODO: to/fromWords
+    #[wasm_bindgen(js_name = fromWords)]
+    pub fn from_words(lang: Language, words: &str) -> Result<Self, IronfishError> {
+        ironfish::keys::OutgoingViewKey::from_words(lang.language_code().as_ref(), words)
+            .map(|key| key.into())
+            .map_err(|err| err.into())
+    }
+
+    #[wasm_bindgen(js_name = toWords)]
+    pub fn to_words(&self, lang: Language) -> String {
+        // `words_key()` may fail only if the language code is invalid, but here we're accepting
+        // `Language`, not an arbitrary input, so the language code is guaranteed to be valid.
+        self.0
+            .words_key(lang.language_code().as_ref())
+            .expect("conversion to words failed")
+    }
 }
 
 wasm_bindgen_wrapper! {

ironfish-rust/src/keys/mod.rs

@@ -182,8 +182,8 @@ impl SaplingKey {
     }
 
     /// Takes a bip-39 phrase as a string and turns it into a SaplingKey instance
-    pub fn from_words(words: String, language: Language) -> Result<Self, IronfishError> {
-        let mnemonic = Mnemonic::from_phrase(&words, language)
+    pub fn from_words(words: &str, language: Language) -> Result<Self, IronfishError> {
+        let mnemonic = Mnemonic::from_phrase(words, language)
             .map_err(|_| IronfishError::new(IronfishErrorKind::InvalidMnemonicString))?;
         let bytes = mnemonic.entropy();
         let mut byte_arr = [0; SPEND_KEY_SIZE];

ironfish-rust/src/keys/test.rs

@@ -127,6 +127,6 @@ fn test_from_and_to_words() {
 
     // Convert from words
     let key =
-        SaplingKey::from_words(words, bip39::Language::English).expect("key should be created");
+        SaplingKey::from_words(&words, bip39::Language::English).expect("key should be created");
     assert_eq!(key.spending_key, key_bytes);
 }

ironfish-rust/src/keys/view_keys.rs

@@ -57,10 +57,10 @@ impl IncomingViewKey {
     }
 
     /// Load a key from a string of words to be decoded into bytes.
-    pub fn from_words(language_code: &str, value: String) -> Result<Self, IronfishError> {
+    pub fn from_words(language_code: &str, value: &str) -> Result<Self, IronfishError> {
         let language = Language::from_language_code(language_code)
             .ok_or_else(|| IronfishError::new(IronfishErrorKind::InvalidLanguageEncoding))?;
-        let mnemonic = Mnemonic::from_phrase(&value, language)
+        let mnemonic = Mnemonic::from_phrase(value, language)
             .map_err(|_| IronfishError::new(IronfishErrorKind::InvalidPaymentAddress))?;
         let bytes = mnemonic.entropy();
         let mut byte_arr = [0; 32];
@@ -227,10 +227,10 @@ impl OutgoingViewKey {
     }
 
     /// Load a key from a string of words to be decoded into bytes.
-    pub fn from_words(language_code: &str, value: String) -> Result<Self, IronfishError> {
+    pub fn from_words(language_code: &str, value: &str) -> Result<Self, IronfishError> {
         let language = Language::from_language_code(language_code)
             .ok_or_else(|| IronfishError::new(IronfishErrorKind::InvalidLanguageEncoding))?;
-        let mnemonic = Mnemonic::from_phrase(&value, language)
+        let mnemonic = Mnemonic::from_phrase(value, language)
             .map_err(|_| IronfishError::new(IronfishErrorKind::InvalidPaymentAddress))?;
         let bytes = mnemonic.entropy();
         let mut view_key = [0; 32];