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

use std::error::Error;

use crate::common::address::Address;
use crate::traits::{BlockHeader, Encode, Proto};
use crate::util::hash::hash;

use crate::serialization::blockHeader::{BlockHeader as ProtoBlockHeader, HeaderPrehash};

use protobuf::{Message as ProtoMessage, RepeatedField};

#[derive(Clone, Debug, PartialEq)]
pub struct Header {
    pub merkle_root: Vec<u8>,
    pub time_stamp: u64,
    pub difficulty: f64,
    pub state_root: Vec<u8>,
    pub previous_hash: Vec<Vec<u8>>,
    pub nonce: u64,
    pub miner: Address,
}
impl BlockHeader for Header {
    fn get_merkle_root(&self) -> &Vec<u8> {
        &self.merkle_root
    }
    fn get_time_stamp(&self) -> u64 {
        self.time_stamp
    }
    fn get_difficulty(&self) -> f64 {
        self.difficulty
    }
    fn get_state_root(&self) -> &Vec<u8> {
        &self.state_root
    }
    fn get_previous_hash(&self) -> Option<&Vec<Vec<u8>>> {
        Some(&self.previous_hash)
    }
    fn get_nonce(&self) -> Option<u64> {
        Some(self.nonce)
    }
    fn get_miner(&self) -> Option<&Address> {
        Some(&self.miner)
    }
}

impl Header {
    pub fn new(
        merkle_root: Vec<u8>,
        time_stamp: u64,
        difficulty: f64,
        state_root: Vec<u8>,
        previous_hash: Vec<Vec<u8>>,
        nonce: u64,
        miner: Address,
    ) -> Header {
        Header {
            merkle_root,
            time_stamp,
            difficulty,
            state_root,
            previous_hash,
            nonce,
            miner,
        }
    }

    pub fn prehash(&self) -> Result<Vec<u8>, Box<Error>> {
        let mut proto_header = HeaderPrehash::new();
        proto_header.set_merkleRoot(self.merkle_root.clone());
        proto_header.set_timeStamp(self.time_stamp);
        proto_header.set_difficulty(self.difficulty);
        proto_header.set_stateRoot(self.state_root.clone());
        proto_header.set_previousHash(RepeatedField::from(self.previous_hash.clone()));
        proto_header.set_miner(self.miner.to_vec());
        let encoding = proto_header.write_to_bytes()?;
        Ok(hash(&encoding, 64))
    }
}

impl Encode for Header {
    fn encode(&self) -> Result<Vec<u8>, Box<Error>> {
        let proto_block_header = self.to_proto()?;
        Ok(proto_block_header.write_to_bytes()?)
    }
}

impl Proto for Header {
    type ProtoType = ProtoBlockHeader;
    fn to_proto(&self) -> Result<Self::ProtoType, Box<Error>> {
        let mut proto_header = Self::ProtoType::new();
        proto_header.set_merkleRoot(self.merkle_root.clone());
        proto_header.set_timeStamp(self.time_stamp);
        proto_header.set_difficulty(self.difficulty);
        proto_header.set_stateRoot(self.state_root.clone());
        proto_header.set_previousHash(RepeatedField::from(self.previous_hash.clone()));
        proto_header.set_nonce(self.nonce);
        proto_header.set_miner(self.miner.to_vec());
        Ok(proto_header)
    }

    fn from_proto(prototype: &Self::ProtoType) -> Result<Self, Box<Error>> {
        let mut miner = [0u8; 20];
        if &prototype.get_miner().len() == &20 {
            miner.copy_from_slice(&prototype.get_miner().to_vec()[0..20]);
        }
        Ok(Self {
            merkle_root: prototype.get_merkleRoot().to_vec(),
            time_stamp: prototype.get_timeStamp(),
            miner: miner,
            nonce: prototype.get_nonce(),
            difficulty: prototype.get_difficulty(),
            previous_hash: prototype.get_previousHash().to_vec(),
            state_root: prototype.get_stateRoot().to_vec(),
        })
    }
}

#[cfg(test)]
mod tests {
    use super::*;
    use crate::traits::ValidAddress;
    use rust_base58::FromBase58;

    #[test]
    fn it_makes_a_header() {
        let merkle_root = vec![
            218, 175, 98, 56, 136, 59, 157, 43, 178, 250, 66, 194, 50, 129, 87, 37, 147, 54, 157,
            79, 238, 83, 118, 209, 92, 202, 25, 32, 246, 230, 153, 39,
        ];
        let state_root = vec![
            121, 132, 139, 154, 165, 229, 182, 152, 126, 204, 58, 142, 150, 220, 236, 119, 144, 1,
            181, 107, 19, 130, 67, 220, 241, 192, 46, 94, 69, 215, 134, 11,
        ];
        let time_stamp = 1515003305000;
        let difficulty = 0 as f64;
        let nonce = 0;
        let miner = Address::from_string(&"H3yGUaF38TxQxoFrqCqPdB2pN9jyBHnaj".to_string()).unwrap();
        let previous_hash = vec!["G4qXusbRyXmf62c8Tsha7iZoyLsVGfka7ynkvb3Esd1d"
            .from_base58()
            .unwrap()];

        let header = Header::new(
            merkle_root.clone(),
            time_stamp,
            difficulty,
            state_root.clone(),
            previous_hash.clone(),
            nonce,
            miner,
        );
        assert_eq!(header.merkle_root, merkle_root);
        assert_eq!(header.state_root, state_root);
        assert_eq!(header.time_stamp, time_stamp);
        assert_eq!(header.difficulty, difficulty);
        assert_eq!(header.nonce, nonce);
        assert_eq!(header.miner, miner);
        assert_eq!(header.previous_hash, previous_hash);
    }

    #[test]
    fn it_makes_a_raw_header() {
        let merkle_root = vec![
            218, 175, 98, 56, 136, 59, 157, 43, 178, 250, 66, 194, 50, 129, 87, 37, 147, 54, 157,
            79, 238, 83, 118, 209, 92, 202, 25, 32, 246, 230, 153, 39,
        ];
        let state_root = vec![
            121, 132, 139, 154, 165, 229, 182, 152, 126, 204, 58, 142, 150, 220, 236, 119, 144, 1,
            181, 107, 19, 130, 67, 220, 241, 192, 46, 94, 69, 215, 134, 11,
        ];
        let time_stamp = 1515003305000;
        let difficulty = 0 as f64;
        let miner = Address::from_string(&"H3yGUaF38TxQxoFrqCqPdB2pN9jyBHnaj".to_string()).unwrap();
        let previous_hash = vec!["G4qXusbRyXmf62c8Tsha7iZoyLsVGfka7ynkvb3Esd1d"
            .from_base58()
            .unwrap()];
        let nonce = 0;
        let header = Header::new(
            merkle_root.clone(),
            time_stamp,
            difficulty,
            state_root.clone(),
            previous_hash.clone(),
            nonce,
            miner,
        );
        let encoding = header.encode().unwrap();
        let expected_encoding = vec![
            10, 32, 223, 218, 236, 54, 245, 118, 35, 75, 80, 237, 79, 63, 61, 46, 46, 228, 77, 128,
            114, 163, 92, 252, 73, 201, 159, 108, 48, 48, 86, 233, 136, 20, 18, 32, 218, 175, 98,
            56, 136, 59, 157, 43, 178, 250, 66, 194, 50, 129, 87, 37, 147, 54, 157, 79, 238, 83,
            118, 209, 92, 202, 25, 32, 246, 230, 153, 39, 26, 32, 121, 132, 139, 154, 165, 229,
            182, 152, 126, 204, 58, 142, 150, 220, 236, 119, 144, 1, 181, 107, 19, 130, 67, 220,
            241, 192, 46, 94, 69, 215, 134, 11, 33, 0, 0, 0, 0, 0, 0, 0, 0, 40, 168, 184, 239, 233,
            139, 44, 48, 0, 58, 20, 213, 49, 13, 190, 194, 137, 35, 119, 16, 249, 57, 125, 207, 78,
            117, 246, 36, 136, 151, 210,
        ];
        let prehash = header.prehash().unwrap();
        let expected_prehash = vec![
            213, 155, 184, 6, 160, 192, 238, 37, 190, 172, 89, 224, 41, 36, 132, 38, 46, 5, 70,
            193, 159, 49, 130, 25, 220, 56, 238, 148, 167, 135, 240, 158, 162, 189, 223, 13, 85,
            156, 251, 105, 34, 21, 90, 14, 21, 248, 16, 183, 136, 77, 231, 102, 80, 183, 192, 177,
            184, 19, 75, 226, 188, 134, 38, 218,
        ];

        assert_eq!(encoding, expected_encoding);
        assert_eq!(prehash, expected_prehash);
    }
}