1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
#![cfg(feature = "full")]

use {
    crate::{
        derivation_path::DerivationPath,
        pubkey::Pubkey,
        signature::Signature,
        signer::{Signer, SignerError},
    },
    ed25519_dalek::Signer as DalekSigner,
    ed25519_dalek_bip32::Error as Bip32Error,
    hmac::Hmac,
    rand::{rngs::OsRng, CryptoRng, RngCore},
    std::{
        error,
        fs::{self, File, OpenOptions},
        io::{Read, Write},
        path::Path,
    },
};

/// A vanilla Ed25519 key pair
#[derive(Debug)]
pub struct Keypair(ed25519_dalek::Keypair);

impl Keypair {
    /// Constructs a new, random `Keypair` using a caller-proveded RNG
    pub fn generate<R>(csprng: &mut R) -> Self
    where
        R: CryptoRng + RngCore,
    {
        Self(ed25519_dalek::Keypair::generate(csprng))
    }

    /// Constructs a new, random `Keypair` using `OsRng`
    pub fn new() -> Self {
        let mut rng = OsRng::default();
        Self::generate(&mut rng)
    }

    /// Recovers a `Keypair` from a byte array
    pub fn from_bytes(bytes: &[u8]) -> Result<Self, ed25519_dalek::SignatureError> {
        ed25519_dalek::Keypair::from_bytes(bytes).map(Self)
    }

    /// Returns this `Keypair` as a byte array
    pub fn to_bytes(&self) -> [u8; 64] {
        self.0.to_bytes()
    }

    /// Recovers a `Keypair` from a base58-encoded string
    pub fn from_base58_string(s: &str) -> Self {
        Self::from_bytes(&bs58::decode(s).into_vec().unwrap()).unwrap()
    }

    /// Returns this `Keypair` as a base58-encoded string
    pub fn to_base58_string(&self) -> String {
        bs58::encode(&self.0.to_bytes()).into_string()
    }

    /// Gets this `Keypair`'s SecretKey
    pub fn secret(&self) -> &ed25519_dalek::SecretKey {
        &self.0.secret
    }
}

impl Signer for Keypair {
    fn pubkey(&self) -> Pubkey {
        Pubkey::new(self.0.public.as_ref())
    }

    fn try_pubkey(&self) -> Result<Pubkey, SignerError> {
        Ok(self.pubkey())
    }

    fn sign_message(&self, message: &[u8]) -> Signature {
        Signature::new(&self.0.sign(message).to_bytes())
    }

    fn try_sign_message(&self, message: &[u8]) -> Result<Signature, SignerError> {
        Ok(self.sign_message(message))
    }
}

impl<T> PartialEq<T> for Keypair
where
    T: Signer,
{
    fn eq(&self, other: &T) -> bool {
        self.pubkey() == other.pubkey()
    }
}

/// Reads a JSON-encoded `Keypair` from a `Reader` implementor
pub fn read_keypair<R: Read>(reader: &mut R) -> Result<Keypair, Box<dyn error::Error>> {
    let bytes: Vec<u8> = serde_json::from_reader(reader)?;
    let dalek_keypair = ed25519_dalek::Keypair::from_bytes(&bytes)
        .map_err(|e| std::io::Error::new(std::io::ErrorKind::Other, e.to_string()))?;
    Ok(Keypair(dalek_keypair))
}

/// Reads a `Keypair` from a file
pub fn read_keypair_file<F: AsRef<Path>>(path: F) -> Result<Keypair, Box<dyn error::Error>> {
    let mut file = File::open(path.as_ref())?;
    read_keypair(&mut file)
}

/// Writes a `Keypair` to a `Write` implementor with JSON-encoding
pub fn write_keypair<W: Write>(
    keypair: &Keypair,
    writer: &mut W,
) -> Result<String, Box<dyn error::Error>> {
    let keypair_bytes = keypair.0.to_bytes();
    let serialized = serde_json::to_string(&keypair_bytes.to_vec())?;
    writer.write_all(&serialized.clone().into_bytes())?;
    Ok(serialized)
}

/// Writes a `Keypair` to a file with JSON-encoding
pub fn write_keypair_file<F: AsRef<Path>>(
    keypair: &Keypair,
    outfile: F,
) -> Result<String, Box<dyn error::Error>> {
    let outfile = outfile.as_ref();

    if let Some(outdir) = outfile.parent() {
        fs::create_dir_all(outdir)?;
    }

    let mut f = {
        #[cfg(not(unix))]
        {
            OpenOptions::new()
        }
        #[cfg(unix)]
        {
            use std::os::unix::fs::OpenOptionsExt;
            OpenOptions::new().mode(0o600)
        }
    }
    .write(true)
    .truncate(true)
    .create(true)
    .open(outfile)?;

    write_keypair(keypair, &mut f)
}

/// Constructs a `Keypair` from caller-provided seed entropy
pub fn keypair_from_seed(seed: &[u8]) -> Result<Keypair, Box<dyn error::Error>> {
    if seed.len() < ed25519_dalek::SECRET_KEY_LENGTH {
        return Err("Seed is too short".into());
    }
    let secret = ed25519_dalek::SecretKey::from_bytes(&seed[..ed25519_dalek::SECRET_KEY_LENGTH])
        .map_err(|e| e.to_string())?;
    let public = ed25519_dalek::PublicKey::from(&secret);
    let dalek_keypair = ed25519_dalek::Keypair { secret, public };
    Ok(Keypair(dalek_keypair))
}

/// Generates a Keypair using Bip32 Hierarchical Derivation if derivation-path is provided;
/// otherwise generates the base Bip44 Solana keypair from the seed
pub fn keypair_from_seed_and_derivation_path(
    seed: &[u8],
    derivation_path: Option<DerivationPath>,
) -> Result<Keypair, Box<dyn error::Error>> {
    let derivation_path = derivation_path.unwrap_or_else(DerivationPath::default);
    bip32_derived_keypair(seed, derivation_path).map_err(|err| err.to_string().into())
}

/// Generates a Keypair using Bip32 Hierarchical Derivation
fn bip32_derived_keypair(
    seed: &[u8],
    derivation_path: DerivationPath,
) -> Result<Keypair, Bip32Error> {
    let extended = ed25519_dalek_bip32::ExtendedSecretKey::from_seed(seed)
        .and_then(|extended| extended.derive(&derivation_path))?;
    let extended_public_key = extended.public_key();
    Ok(Keypair(ed25519_dalek::Keypair {
        secret: extended.secret_key,
        public: extended_public_key,
    }))
}

pub fn generate_seed_from_seed_phrase_and_passphrase(
    seed_phrase: &str,
    passphrase: &str,
) -> Vec<u8> {
    const PBKDF2_ROUNDS: u32 = 2048;
    const PBKDF2_BYTES: usize = 64;

    let salt = format!("mnemonic{}", passphrase);

    let mut seed = vec![0u8; PBKDF2_BYTES];
    pbkdf2::pbkdf2::<Hmac<sha2::Sha512>>(
        seed_phrase.as_bytes(),
        salt.as_bytes(),
        PBKDF2_ROUNDS,
        &mut seed,
    );
    seed
}

pub fn keypair_from_seed_phrase_and_passphrase(
    seed_phrase: &str,
    passphrase: &str,
) -> Result<Keypair, Box<dyn error::Error>> {
    keypair_from_seed(&generate_seed_from_seed_phrase_and_passphrase(
        seed_phrase,
        passphrase,
    ))
}

#[cfg(test)]
mod tests {
    use {
        super::*,
        bip39::{Language, Mnemonic, MnemonicType, Seed},
        std::mem,
    };

    fn tmp_file_path(name: &str) -> String {
        use std::env;
        let out_dir = env::var("FARF_DIR").unwrap_or_else(|_| "farf".to_string());
        let keypair = Keypair::new();

        format!("{}/tmp/{}-{}", out_dir, name, keypair.pubkey())
    }

    #[test]
    fn test_write_keypair_file() {
        let outfile = tmp_file_path("test_write_keypair_file.json");
        let serialized_keypair = write_keypair_file(&Keypair::new(), &outfile).unwrap();
        let keypair_vec: Vec<u8> = serde_json::from_str(&serialized_keypair).unwrap();
        assert!(Path::new(&outfile).exists());
        assert_eq!(
            keypair_vec,
            read_keypair_file(&outfile).unwrap().0.to_bytes().to_vec()
        );

        #[cfg(unix)]
        {
            use std::os::unix::fs::PermissionsExt;
            assert_eq!(
                File::open(&outfile)
                    .expect("open")
                    .metadata()
                    .expect("metadata")
                    .permissions()
                    .mode()
                    & 0o777,
                0o600
            );
        }

        assert_eq!(
            read_keypair_file(&outfile).unwrap().pubkey().as_ref().len(),
            mem::size_of::<Pubkey>()
        );
        fs::remove_file(&outfile).unwrap();
        assert!(!Path::new(&outfile).exists());
    }

    #[test]
    fn test_write_keypair_file_overwrite_ok() {
        let outfile = tmp_file_path("test_write_keypair_file_overwrite_ok.json");

        write_keypair_file(&Keypair::new(), &outfile).unwrap();
        write_keypair_file(&Keypair::new(), &outfile).unwrap();
    }

    #[test]
    fn test_write_keypair_file_truncate() {
        let outfile = tmp_file_path("test_write_keypair_file_truncate.json");

        write_keypair_file(&Keypair::new(), &outfile).unwrap();
        read_keypair_file(&outfile).unwrap();

        // Ensure outfile is truncated
        {
            let mut f = File::create(&outfile).unwrap();
            f.write_all(String::from_utf8([b'a'; 2048].to_vec()).unwrap().as_bytes())
                .unwrap();
        }
        write_keypair_file(&Keypair::new(), &outfile).unwrap();
        read_keypair_file(&outfile).unwrap();
    }

    #[test]
    fn test_keypair_from_seed() {
        let good_seed = vec![0; 32];
        assert!(keypair_from_seed(&good_seed).is_ok());

        let too_short_seed = vec![0; 31];
        assert!(keypair_from_seed(&too_short_seed).is_err());
    }

    #[test]
    fn test_keypair_from_seed_phrase_and_passphrase() {
        let mnemonic = Mnemonic::new(MnemonicType::Words12, Language::English);
        let passphrase = "42";
        let seed = Seed::new(&mnemonic, passphrase);
        let expected_keypair = keypair_from_seed(seed.as_bytes()).unwrap();
        let keypair =
            keypair_from_seed_phrase_and_passphrase(mnemonic.phrase(), passphrase).unwrap();
        assert_eq!(keypair.pubkey(), expected_keypair.pubkey());
    }

    #[test]
    fn test_keypair() {
        let keypair = keypair_from_seed(&[0u8; 32]).unwrap();
        let pubkey = keypair.pubkey();
        let data = [1u8];
        let sig = keypair.sign_message(&data);

        // Signer
        assert_eq!(keypair.try_pubkey().unwrap(), pubkey);
        assert_eq!(keypair.pubkey(), pubkey);
        assert_eq!(keypair.try_sign_message(&data).unwrap(), sig);
        assert_eq!(keypair.sign_message(&data), sig);

        // PartialEq
        let keypair2 = keypair_from_seed(&[0u8; 32]).unwrap();
        assert_eq!(keypair, keypair2);
    }
}