bch 0.1.1

A Rust library for working with Bitcoin Cash
Documentation 
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

use address::AddressType;
use network::Network;
use rust_base58::base58::{FromBase58, ToBase58};
use util::{sha256d, Error, Hash160, Result};

/// Converts a public key hash to its legacy address
pub fn legacyaddr_encode(hash160: &Hash160, addr_type: AddressType, network: Network) -> String {
    let mut v = Vec::with_capacity(1 + hash160.0.len() + 2);
    v.push(match addr_type {
        AddressType::P2PKH => network.legacyaddr_pubkeyhash_flag(),
        AddressType::P2SH => network.legacyaddr_script_flag(),
    });
    v.extend_from_slice(&hash160.0);
    let checksum = sha256d(&v).0;
    v.push(checksum[0]);
    v.push(checksum[1]);
    v.push(checksum[2]);
    v.push(checksum[3]);
    let b: &[u8] = v.as_ref();
    b.to_base58()
}

/// Decodes a legacy address to a public key hash
pub fn legacyaddr_decode(input: &str, network: Network) -> Result<(Hash160, AddressType)> {
    // Make sure addr is at least some minimum to verify checksum and addr type
    // We will check the private key size later.
    let v = input.from_base58()?;
    if v.len() < 6 {
        let msg = format!("Base58 address not long enough: {}", v.len());
        return Err(Error::BadData(msg));
    }

    // Verify checksum
    let v0 = &v[0..v.len() - 4];
    let v1 = &v[v.len() - 4..v.len()];
    let cs = sha256d(v0).0;
    if v1[0] != cs[0] || v1[1] != cs[1] || v1[2] != cs[2] || v1[3] != cs[3] {
        let msg = format!("Bad checksum: {:?} != {:?}", &cs[..4], v1);
        return Err(Error::BadData(msg));
    }

    // Extract address type
    let addr_type_byte = v0[0];
    let addr_type = if addr_type_byte == network.legacyaddr_pubkeyhash_flag() {
        AddressType::P2PKH
    } else if addr_type_byte == network.legacyaddr_script_flag() {
        AddressType::P2SH
    } else {
        let msg = format!("Unknown address type {}", addr_type_byte);
        return Err(Error::BadData(msg));
    };

    // Extract hash160 address and return
    if v0.len() != 21 {
        let msg = format!("Hash160 address not long enough: {}", v0.len() - 1);
        return Err(Error::BadData(msg));
    }
    let mut hash160addr = [0; 20];
    hash160addr.clone_from_slice(&v0[1..]);
    Ok((Hash160(hash160addr), addr_type))
}

#[cfg(test)]
mod tests {
    use super::*;
    use hex;
    use util::hash160;

    #[test]
    fn to_legacyaddr() {
        let pubkey_hex = "04005937fd439b3c19014d5f328df8c7ed514eaaf41c1980b8aeab461dffb23fbf3317e42395db24a52ce9fc947d9c22f54dc3217c8b11dfc7a09c59e0dca591d3";
        let pubkeyhash = hash160(&hex::decode(pubkey_hex).unwrap());
        let legacyaddr = legacyaddr_encode(&pubkeyhash, AddressType::P2PKH, Network::Mainnet);
        assert!(legacyaddr == "1NM2HFXin4cEQRBLjkNZAS98qLX9JKzjKn");
    }

    #[test]
    fn from_legacyaddr() {
        let legacyaddr = "1NM2HFXin4cEQRBLjkNZAS98qLX9JKzjKn";
        let result = legacyaddr_decode(&legacyaddr, Network::Mainnet).unwrap();
        let hash160 = result.0;
        let addr_type = result.1;
        assert!(addr_type == AddressType::P2PKH);
        assert!(hex::encode(hash160.0) == "ea2407829a5055466b27784cde8cf463167946bf");
    }

    #[test]
    fn from_legacyaddr_errors() {
        assert!(legacyaddr_decode("0", Network::Mainnet).is_err());
        assert!(legacyaddr_decode("1000000000000000000000000000000000", Network::Mainnet).is_err());
    }
}