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

// Copyright 2019-2022 PureStake Inc.
// This file is part of Moonbeam.

// Moonbeam is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.

// Moonbeam is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.

// You should have received a copy of the GNU General Public License
// along with Moonbeam.  If not, see <http://www.gnu.org/licenses/>.

use bip32::{
	Error as Bip32Error, ExtendedPrivateKey, PrivateKey as PrivateKeyT, PrivateKeyBytes,
	PublicKey as PublicKeyT, PublicKeyBytes,
};
use bip39::{Language, Mnemonic, MnemonicType, Seed};
use clap::Parser;
use libsecp256k1::{PublicKey, SecretKey};
use primitive_types::H256;
use sp_runtime::traits::IdentifyAccount;

#[derive(Debug, Parser)]
pub struct GenerateAccountKey {
	/// Generate 12 words mnemonic instead of 24
	#[clap(long, short = 'w')]
	w12: bool,

	/// Specify the mnemonic
	#[clap(long, short = 'm')]
	mnemonic: Option<String>,

	/// The account index to use in the derivation path
	#[clap(long = "account-index", short = 'a')]
	account_index: Option<u32>,
}

impl GenerateAccountKey {
	pub fn run(&self) {
		// Retrieve the mnemonic from the args or generate random ones
		let mnemonic = if let Some(phrase) = &self.mnemonic {
			Mnemonic::from_phrase(phrase, Language::English).expect("invalid mnemonic")
		} else {
			match self.w12 {
				true => Mnemonic::new(MnemonicType::Words12, Language::English),
				false => Mnemonic::new(MnemonicType::Words24, Language::English),
			}
		};

		// Retrieves the seed from the mnemonic
		let seed = Seed::new(&mnemonic, "");
		let derivation_path = format!("m/44'/60'/0'/0/{}", self.account_index.unwrap_or(0));
		let private_key = if let Some(private_key) =
			derivation_path.parse().ok().and_then(|derivation_path| {
				let extended = ExtendedPrivateKey::<Secp256k1SecretKey>::derive_from_path(
					&seed,
					&derivation_path,
				)
				.expect("invalid extended private key");
				Some(extended.private_key().0)
			}) {
			private_key
		} else {
			panic!("invalid extended private key");
		};

		// Retrieves the public key
		let public_key = PublicKey::from_secret_key(&private_key);

		// Convert into Ethereum-style address.
		let signer: account::EthereumSigner = public_key.into();
		let address = signer.into_account();

		println!("Address:      {:?}", address);
		println!("Mnemonic:     {}", mnemonic.phrase());
		println!("Private Key:  {:?}", H256::from(private_key.serialize()));
		println!("Path:         {}", derivation_path);
	}
}

// `libsecp256k1::PublicKey` wrapped type
pub struct Secp256k1PublicKey(pub PublicKey);
// `libsecp256k1::Secret`  wrapped type
pub struct Secp256k1SecretKey(pub SecretKey);

impl PublicKeyT for Secp256k1PublicKey {
	fn from_bytes(bytes: PublicKeyBytes) -> Result<Self, Bip32Error> {
		let public = PublicKey::parse_compressed(&bytes).map_err(|_| return Bip32Error::Decode)?;
		Ok(Self(public))
	}

	fn to_bytes(&self) -> PublicKeyBytes {
		self.0.serialize_compressed()
	}

	fn derive_child(&self, other: PrivateKeyBytes) -> Result<Self, Bip32Error> {
		let mut child = self.0.clone();
		let secret = SecretKey::parse(&other).map_err(|_| return Bip32Error::Decode)?;
		let _ = child.tweak_add_assign(&secret);
		Ok(Self(child))
	}
}

impl PrivateKeyT for Secp256k1SecretKey {
	type PublicKey = Secp256k1PublicKey;

	fn from_bytes(bytes: &PrivateKeyBytes) -> Result<Self, Bip32Error> {
		let secret = SecretKey::parse(&bytes).map_err(|_| return Bip32Error::Decode)?;
		Ok(Self(secret))
	}

	fn to_bytes(&self) -> PrivateKeyBytes {
		self.0.serialize()
	}

	fn derive_child(&self, other: PrivateKeyBytes) -> Result<Self, Bip32Error> {
		let mut child = self.0.clone();
		let secret = SecretKey::parse(&other).map_err(|_| return Bip32Error::Decode)?;
		let _ = child.tweak_add_assign(&secret);
		Ok(Self(child))
	}

	fn public_key(&self) -> Self::PublicKey {
		Secp256k1PublicKey(PublicKey::from_secret_key(&self.0))
	}
}