Block header parsing and transaction ID computation

zcash_primitives/Cargo.toml

@@ -8,6 +8,7 @@ authors = [
 [dependencies]
 byteorder = "1"
 ff = { path = "../ff" }
+hex = "0.3"
 lazy_static = "1"
 pairing = { path = "../pairing" }
 rand = "0.4"

zcash_primitives/src/block.rs

@@ -0,0 +1,42 @@
+use hex;
+use std::fmt;
+use std::ops::Deref;
+
+#[derive(Clone, Copy, Debug, PartialEq, Eq, Hash)]
+pub struct BlockHash(pub [u8; 32]);
+
+impl fmt::Display for BlockHash {
+    fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
+        let mut data = self.0.to_vec();
+        data.reverse();
+        formatter.write_str(&hex::encode(data))
+    }
+}
+
+/// A Zcash block header.
+pub struct BlockHeader(BlockHeaderData);
+
+impl Deref for BlockHeader {
+    type Target = BlockHeaderData;
+
+    fn deref(&self) -> &BlockHeaderData {
+        &self.0
+    }
+}
+
+pub struct BlockHeaderData {
+    pub version: i32,
+    pub prev_block: BlockHash,
+    pub merkle_root: [u8; 32],
+    pub final_sapling_root: [u8; 32],
+    pub time: u32,
+    pub bits: u32,
+    pub nonce: [u8; 32],
+    pub solution: Vec<u8>,
+}
+
+impl BlockHeaderData {
+    pub fn freeze(self) -> BlockHeader {
+        BlockHeader(self)
+    }
+}

zcash_primitives/src/lib.rs

@@ -4,12 +4,14 @@ extern crate lazy_static;
 extern crate blake2_rfc;
 extern crate byteorder;
 extern crate ff;
+extern crate hex;
 extern crate pairing;
 extern crate rand;
 extern crate sapling_crypto;
 
 use sapling_crypto::jubjub::JubjubBls12;
 
+pub mod block;
 pub mod sapling;
 mod serialize;
 pub mod transaction;

zcash_primitives/src/transaction/mod.rs

@@ -1,5 +1,7 @@
 use byteorder::{LittleEndian, ReadBytesExt, WriteBytesExt};
+use hex;
 use sapling_crypto::redjubjub::Signature;
+use std::fmt;
 use std::io::{self, Read, Write};
 use std::ops::Deref;
 
@@ -20,6 +22,17 @@ const OVERWINTER_TX_VERSION: u32 = 3;
 const SAPLING_VERSION_GROUP_ID: u32 = 0x892F2085;
 const SAPLING_TX_VERSION: u32 = 4;
 
+#[derive(Clone, Copy, Debug, PartialEq, Eq, Hash)]
+pub struct TxId(pub [u8; 32]);
+
+impl fmt::Display for TxId {
+    fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
+        let mut data = self.0.to_vec();
+        data.reverse();
+        formatter.write_str(&hex::encode(data))
+    }
+}
+
 /// A Zcash transaction.
 #[derive(Debug)]
 pub struct Transaction(TransactionData);