Merge pull request #25 from gavofyork/gav

Secure trie functions & structs.

src/bytes.rs

@@ -92,7 +92,10 @@ pub type Bytes = Vec<u8>;
 
 /// Slice of bytes to underlying memory
 pub trait BytesConvertable {
+	// TODO: rename to as_slice
 	fn bytes(&self) -> &[u8];
+	fn as_slice(&self) -> &[u8] { self.bytes() }
+	fn to_bytes(&self) -> Bytes { self.as_slice().to_vec() }
 }
 
 impl<'a> BytesConvertable for &'a [u8] {

src/error.rs

@@ -13,7 +13,7 @@ pub enum EthcoreError {
 	FromHex(FromHexError),
 	BaseData(BaseDataError),
 	BadSize,
-	UnknownName
+	UnknownName,
 }
 
 impl From<FromHexError> for EthcoreError {

src/rlp/tests.rs

@@ -4,7 +4,7 @@ use self::json_tests::rlp as rlptest;
 use std::{fmt, cmp};
 use std::str::FromStr;
 use rlp;
-use rlp::{UntrustedRlp, RlpStream, Decodable, View, Stream, Encodable};
+use rlp::{UntrustedRlp, RlpStream, View, Stream};
 use uint::U256;
 
 #[test]

src/trie/mod.rs

@@ -4,8 +4,12 @@ pub mod journal;
 pub mod node;
 pub mod triedb;
 pub mod triedbmut;
+pub mod sectriedb;
+pub mod sectriedbmut;
 
 pub use self::trietraits::*;
 pub use self::standardmap::*;
 pub use self::triedbmut::*;
 pub use self::triedb::*;
+pub use self::sectriedbmut::*;
+pub use self::sectriedb::*;

src/trie/sectriedb.rs

@@ -0,0 +1,59 @@
+use hash::*;
+use sha3::*;
+use hashdb::*;
+use rlp::*;
+use super::triedb::*;
+use super::trietraits::*;
+
+/// A `Trie` implementation which hashes keys and uses a generic `HashDB` backing database.
+/// 
+/// Use it as a `Trie` trait object. You can use `raw()` to get the backing TrieDB object.
+pub struct SecTrieDB<'db> {
+	raw: TrieDB<'db>
+}
+
+impl<'db> SecTrieDB<'db> {
+	/// Create a new trie with the backing database `db` and empty `root`
+	/// Initialise to the state entailed by the genesis block.
+	/// This guarantees the trie is built correctly.
+	pub fn new(db: &'db HashDB, root: &'db H256) -> Self { 
+		SecTrieDB { raw: TrieDB::new(db, root) }
+	}
+
+	/// Get a reference to the underlying raw TrieDB struct.
+	pub fn raw(&self) -> &TrieDB {
+		&self.raw
+	}
+
+	/// Get a mutable reference to the underlying raw TrieDB struct.
+	pub fn raw_mut(&mut self) -> &TrieDB {
+		&mut self.raw
+	}
+}
+
+impl<'db> Trie for SecTrieDB<'db> {
+	fn root(&self) -> &H256 { self.raw.root() }
+
+	fn contains(&self, key: &[u8]) -> bool {
+		self.raw.contains(&key.sha3())
+	}
+
+	fn get<'a, 'key>(&'a self, key: &'key [u8]) -> Option<&'a [u8]> where 'a: 'key {
+		self.raw.get(&key.sha3())
+	}
+}
+
+#[test]
+fn trie_to_sectrie() {
+	use memorydb::*;
+	use super::triedbmut::*;
+
+	let mut memdb = MemoryDB::new();
+	let mut root = H256::new();
+	{
+		let mut t = TrieDBMut::new(&mut memdb, &mut root);
+		t.insert(&(&[0x01u8, 0x23]).sha3(), &[0x01u8, 0x23]);
+	}
+	let t = SecTrieDB::new(&memdb, &root);
+	assert_eq!(t.get(&[0x01u8, 0x23]).unwrap(), &[0x01u8, 0x23]);
+}

src/trie/sectriedbmut.rs

@@ -0,0 +1,65 @@
+use hash::*;
+use sha3::*;
+use hashdb::*;
+use rlp::*;
+use super::triedbmut::*;
+use super::trietraits::*;
+
+/// A mutable `Trie` implementation which hashes keys and uses a generic `HashDB` backing database.
+/// 
+/// Use it as a `Trie` or `TrieMut` trait object. You can use `raw()` to get the backing TrieDBMut object.
+pub struct SecTrieDBMut<'db> {
+	raw: TrieDBMut<'db>
+}
+
+impl<'db> SecTrieDBMut<'db> {
+	/// Create a new trie with the backing database `db` and empty `root`
+	/// Initialise to the state entailed by the genesis block.
+	/// This guarantees the trie is built correctly.
+	pub fn new(db: &'db mut HashDB, root: &'db mut H256) -> Self { 
+		SecTrieDBMut { raw: TrieDBMut::new(db, root) }
+	}
+
+	/// Create a new trie with the backing database `db` and `root`
+	/// Panics, if `root` does not exist
+	pub fn new_existing(db: &'db mut HashDB, root: &'db mut H256) -> Self {
+		SecTrieDBMut { raw: TrieDBMut::new_existing(db, root) }
+	}
+}
+
+impl<'db> Trie for SecTrieDBMut<'db> {
+	fn root(&self) -> &H256 { self.raw.root() }
+
+	fn contains(&self, key: &[u8]) -> bool {
+		self.raw.contains(&key.sha3())
+	}
+
+	fn get<'a, 'key>(&'a self, key: &'key [u8]) -> Option<&'a [u8]> where 'a: 'key {
+		self.raw.get(&key.sha3())
+	}
+}
+
+impl<'db> TrieMut for SecTrieDBMut<'db> {
+	fn insert(&mut self, key: &[u8], value: &[u8]) {
+		self.raw.insert(&key.sha3(), value);
+	}
+
+	fn remove(&mut self, key: &[u8]) {
+		self.raw.remove(&key.sha3());
+	}
+}
+
+#[test]
+fn sectrie_to_trie() {
+	use memorydb::*;
+	use super::triedb::*;
+
+	let mut memdb = MemoryDB::new();
+	let mut root = H256::new();
+	{
+		let mut t = SecTrieDBMut::new(&mut memdb, &mut root);
+		t.insert(&[0x01u8, 0x23], &[0x01u8, 0x23]);
+	}
+	let t = TrieDB::new(&memdb, &root);
+	assert_eq!(t.get(&(&[0x01u8, 0x23]).sha3()).unwrap(), &[0x01u8, 0x23]);
+}

src/trie/triedbmut.rs

@@ -9,18 +9,6 @@ use super::node::*;
 use super::journal::*;
 use super::trietraits::*;
 
-pub struct TrieDBMut<'db> {
-	db: &'db mut HashDB,
-	root: &'db mut H256,
-	pub hash_count: usize,
-}
-
-/// Option-like type allowing either a Node object passthrough or Bytes in the case of data alteration.
-enum MaybeChanged<'a> {
-	Same(Node<'a>),
-	Changed(Bytes),
-}
-
 /// A `Trie` implementation using a generic `HashDB` backing database.
 /// 
 /// Use it as a `Trie` trait object. You can use `db()` to get the backing database object, `keys`
@@ -52,6 +40,18 @@ enum MaybeChanged<'a> {
 ///   assert!(t.db_items_remaining().is_empty());
 /// }
 /// ```
+pub struct TrieDBMut<'db> {
+	db: &'db mut HashDB,
+	root: &'db mut H256,
+	pub hash_count: usize,
+}
+
+/// Option-like type allowing either a Node object passthrough or Bytes in the case of data alteration.
+enum MaybeChanged<'a> {
+	Same(Node<'a>),
+	Changed(Bytes),
+}
+
 impl<'db> TrieDBMut<'db> {
 	/// Create a new trie with the backing database `db` and empty `root`
 	/// Initialise to the state entailed by the genesis block.

src/triehash.rs

@@ -77,6 +77,41 @@ pub fn trie_root(input: Vec<(Vec<u8>, Vec<u8>)>) -> H256 {
 	gen_trie_root(gen_input)
 }
 
+/// Generates a key-hashed (secure) trie root hash for a vector of key-values.
+///
+/// ```rust
+/// extern crate ethcore_util as util;
+/// use std::str::FromStr;
+/// use util::triehash::*;
+/// use util::hash::*;
+/// 
+/// fn main() {
+/// 	let v = vec![
+/// 		(From::from("doe"), From::from("reindeer")),
+/// 		(From::from("dog"), From::from("puppy")),
+/// 		(From::from("dogglesworth"), From::from("cat")),
+/// 	];
+///
+/// 	let root = "d4cd937e4a4368d7931a9cf51686b7e10abb3dce38a39000fd7902a092b64585";
+/// 	assert_eq!(sec_trie_root(v), H256::from_str(root).unwrap());
+/// }
+/// ```
+pub fn sec_trie_root(input: Vec<(Vec<u8>, Vec<u8>)>) -> H256 {
+	let gen_input = input
+		// first put elements into btree to sort them and to remove duplicates
+		.into_iter()
+		.fold(BTreeMap::new(), | mut acc, (k, v) | {
+			acc.insert(k.sha3().to_vec(), v);
+			acc
+		})
+		// then move them to a vector
+		.into_iter()
+		.map(|(k, v)| (as_nibbles(&k), v) )
+		.collect();
+
+	gen_trie_root(gen_input)
+}
+
 fn gen_trie_root(input: Vec<(Vec<u8>, Vec<u8>)>) -> H256 {
 	let mut stream = RlpStream::new();
 	hash256rlp(&input, 0, &mut stream);