Const time comparison

ethcrypto/Cargo.toml

@@ -9,4 +9,4 @@ tiny-keccak = "1.3"
 eth-secp256k1 = { git = "https://github.com/paritytech/rust-secp256k1" }
 ethkey = { path = "../ethkey" }
 ethereum-types = "0.2"
-subtle = "0.1"
+subtle = "0.5"

ethcrypto/src/lib.rs

@@ -308,7 +308,7 @@ pub mod ecies {
 		hmac.raw_result(&mut mac);
 
 		// constant time compare to avoid timing attack.
-		if ::subtle::arrays_equal(&mac[..], msg_mac) != 1 {
+		if ::subtle::slices_equal(&mac[..], msg_mac) != 1 {
 			return Err(Error::InvalidMessage);
 		}
 

ethstore/Cargo.toml

@@ -22,6 +22,10 @@ ethereum-types = "0.2"
 dir = { path = "../util/dir" }
 smallvec = "0.4"
 parity-wordlist = "1.0"
+subtle = "0.5"
 tempdir = "0.3"
 
+[dev-dependencies]
+matches = "0.1"
+
 [lib]

ethstore/src/account/crypto.rs

@@ -21,6 +21,7 @@ use crypto::Keccak256;
 use random::Random;
 use smallvec::SmallVec;
 use account::{Cipher, Kdf, Aes128Ctr, Pbkdf2, Prf};
+use subtle;
 
 /// Encrypted data
 #[derive(Debug, PartialEq, Clone)]
@@ -136,7 +137,7 @@ impl Crypto {
 
 		let mac = crypto::derive_mac(&derived_right_bits, &self.ciphertext).keccak256();
 
-		if mac != self.mac {
+		if subtle::slices_equal(&mac, &self.mac) == 0 {
 			return Err(Error::InvalidPassword);
 		}
 
@@ -158,7 +159,7 @@ impl Crypto {
 #[cfg(test)]
 mod tests {
 	use ethkey::{Generator, Random};
-	use super::Crypto;
+	use super::{Crypto, Error};
 
 	#[test]
 	fn crypto_with_secret_create() {
@@ -169,11 +170,10 @@ mod tests {
 	}
 
 	#[test]
-	#[should_panic]
 	fn crypto_with_secret_invalid_password() {
 		let keypair = Random.generate().unwrap();
 		let crypto = Crypto::with_secret(keypair.secret(), "this is sparta", 10240);
-		let _ = crypto.secret("this is sparta!").unwrap();
+		assert_matches!(crypto.secret("this is sparta!"), Err(Error::InvalidPassword))
 	}
 
 	#[test]

ethstore/src/lib.rs

@@ -28,6 +28,7 @@ extern crate rustc_hex;
 extern crate serde;
 extern crate serde_json;
 extern crate smallvec;
+extern crate subtle;
 extern crate time;
 extern crate tiny_keccak;
 extern crate tempdir;
@@ -42,6 +43,10 @@ extern crate log;
 #[macro_use]
 extern crate serde_derive;
 
+#[cfg(test)]
+#[macro_use]
+extern crate matches;
+
 pub mod accounts_dir;
 pub mod ethkey;