On-chain ACL checker for secretstore (#5015)

* ECDKG protocol prototype

* added test for enc/dec math

* get rid of decryption_session

* added licenses

* fix after merge

* get rid of unused serde dependency

* doc

* decryption session [without commutative enc]

* failed_dec_session

* fixed tests

* added commen

* added more decryption session tests

* helper to localize an issue

* more computations to localize error

* decryption_session::SessionParams

* added tests for EC math to localize problem

* secretstore network transport

* encryption_session_works_over_network

* network errors processing

* connecting to KeyServer

* licenses

* get rid of debug println-s

* fixed secretstore args

* encryption results are stored in KS database

* decryption protocol works over network

* enc/dec Session traits

* fixing warnings

* fix after merge

* on-chain ACL checker proto

* fixed compilation

* fixed compilation

* finally fixed <odd>-of-N-scheme

* temporary commented test

* 1-of-N works in math

* scheme 1-of-N works

* updated AclStorage with real contract ABI

* remove unnecessary unsafety

* fixed grumbles

* wakeup on access denied

* fix after merge

* fix after merge

* moved contract to native-contracts lib

Cargo.lock

@@ -635,6 +635,8 @@ name = "ethcore-secretstore"
 version = "1.0.0"
 dependencies = [
  "byteorder 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "ethabi 1.0.4 (registry+https://github.com/rust-lang/crates.io-index)",
+ "ethcore 1.7.0",
  "ethcore-devtools 1.7.0",
  "ethcore-ipc 1.7.0",
  "ethcore-ipc-codegen 1.7.0",
@@ -646,6 +648,7 @@ dependencies = [
  "futures-cpupool 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "hyper 0.10.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.3.6 (registry+https://github.com/rust-lang/crates.io-index)",
+ "native-contracts 0.1.0",
  "parking_lot 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustc-serialize 0.3.19 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde 0.9.6 (registry+https://github.com/rust-lang/crates.io-index)",

ethcore/native_contracts/build.rs

@@ -23,6 +23,7 @@ use std::io::Write;
 // TODO: `include!` these from files where they're pretty-printed?
 const REGISTRY_ABI: &'static str = r#"[{"constant":true,"inputs":[{"name":"_data","type":"address"}],"name":"canReverse","outputs":[{"name":"","type":"bool"}],"payable":false,"type":"function"},{"constant":false,"inputs":[{"name":"_new","type":"address"}],"name":"setOwner","outputs":[],"payable":false,"type":"function"},{"constant":false,"inputs":[{"name":"_name","type":"bytes32"},{"name":"_key","type":"string"},{"name":"_value","type":"bytes32"}],"name":"setData","outputs":[{"name":"success","type":"bool"}],"payable":false,"type":"function"},{"constant":false,"inputs":[{"name":"_name","type":"string"}],"name":"confirmReverse","outputs":[{"name":"success","type":"bool"}],"payable":false,"type":"function"},{"constant":false,"inputs":[{"name":"_name","type":"bytes32"}],"name":"reserve","outputs":[{"name":"success","type":"bool"}],"payable":true,"type":"function"},{"constant":false,"inputs":[{"name":"_name","type":"bytes32"}],"name":"drop","outputs":[{"name":"success","type":"bool"}],"payable":false,"type":"function"},{"constant":true,"inputs":[{"name":"_name","type":"bytes32"},{"name":"_key","type":"string"}],"name":"getAddress","outputs":[{"name":"","type":"address"}],"payable":false,"type":"function"},{"constant":false,"inputs":[{"name":"_amount","type":"uint256"}],"name":"setFee","outputs":[{"name":"","type":"bool"}],"payable":false,"type":"function"},{"constant":false,"inputs":[{"name":"_name","type":"bytes32"},{"name":"_to","type":"address"}],"name":"transfer","outputs":[{"name":"success","type":"bool"}],"payable":false,"type":"function"},{"constant":true,"inputs":[],"name":"owner","outputs":[{"name":"","type":"address"}],"payable":false,"type":"function"},{"constant":true,"inputs":[{"name":"_name","type":"bytes32"},{"name":"_key","type":"string"}],"name":"getData","outputs":[{"name":"","type":"bytes32"}],"payable":false,"type":"function"},{"constant":true,"inputs":[{"name":"_name","type":"bytes32"}],"name":"reserved","outputs":[{"name":"reserved","type":"bool"}],"payable":false,"type":"function"},{"constant":false,"inputs":[],"name":"drain","outputs":[{"name":"","type":"bool"}],"payable":false,"type":"function"},{"constant":false,"inputs":[{"name":"_name","type":"string"},{"name":"_who","type":"address"}],"name":"proposeReverse","outputs":[{"name":"success","type":"bool"}],"payable":false,"type":"function"},{"constant":true,"inputs":[{"name":"_name","type":"bytes32"}],"name":"hasReverse","outputs":[{"name":"","type":"bool"}],"payable":false,"type":"function"},{"constant":true,"inputs":[{"name":"_name","type":"bytes32"},{"name":"_key","type":"string"}],"name":"getUint","outputs":[{"name":"","type":"uint256"}],"payable":false,"type":"function"},{"constant":true,"inputs":[],"name":"fee","outputs":[{"name":"","type":"uint256"}],"payable":false,"type":"function"},{"constant":true,"inputs":[{"name":"_name","type":"bytes32"}],"name":"getOwner","outputs":[{"name":"","type":"address"}],"payable":false,"type":"function"},{"constant":true,"inputs":[{"name":"_name","type":"bytes32"}],"name":"getReverse","outputs":[{"name":"","type":"address"}],"payable":false,"type":"function"},{"constant":true,"inputs":[{"name":"_data","type":"address"}],"name":"reverse","outputs":[{"name":"","type":"string"}],"payable":false,"type":"function"},{"constant":false,"inputs":[{"name":"_name","type":"bytes32"},{"name":"_key","type":"string"},{"name":"_value","type":"uint256"}],"name":"setUint","outputs":[{"name":"success","type":"bool"}],"payable":false,"type":"function"},{"constant":false,"inputs":[{"name":"_name","type":"string"},{"name":"_who","type":"address"}],"name":"confirmReverseAs","outputs":[{"name":"success","type":"bool"}],"payable":false,"type":"function"},{"constant":false,"inputs":[],"name":"removeReverse","outputs":[],"payable":false,"type":"function"},{"constant":false,"inputs":[{"name":"_name","type":"bytes32"},{"name":"_key","type":"string"},{"name":"_value","type":"address"}],"name":"setAddress","outputs":[{"name":"success","type":"bool"}],"payable":false,"type":"function"}]"#;
 const SERVICE_TRANSACTION_ABI: &'static str = r#"[{"constant":false,"inputs":[{"name":"_new","type":"address"}],"name":"setOwner","outputs":[],"payable":false,"type":"function"},{"constant":false,"inputs":[{"name":"_who","type":"address"}],"name":"certify","outputs":[],"payable":false,"type":"function"},{"constant":true,"inputs":[{"name":"_who","type":"address"},{"name":"_field","type":"string"}],"name":"getAddress","outputs":[{"name":"","type":"address"}],"payable":false,"type":"function"},{"constant":false,"inputs":[{"name":"_who","type":"address"}],"name":"revoke","outputs":[],"payable":false,"type":"function"},{"constant":true,"inputs":[],"name":"owner","outputs":[{"name":"","type":"address"}],"payable":false,"type":"function"},{"constant":true,"inputs":[],"name":"delegate","outputs":[{"name":"","type":"address"}],"payable":false,"type":"function"},{"constant":true,"inputs":[{"name":"_who","type":"address"},{"name":"_field","type":"string"}],"name":"getUint","outputs":[{"name":"","type":"uint256"}],"payable":false,"type":"function"},{"constant":false,"inputs":[{"name":"_new","type":"address"}],"name":"setDelegate","outputs":[],"payable":false,"type":"function"},{"constant":true,"inputs":[{"name":"_who","type":"address"}],"name":"certified","outputs":[{"name":"","type":"bool"}],"payable":false,"type":"function"},{"constant":true,"inputs":[{"name":"_who","type":"address"},{"name":"_field","type":"string"}],"name":"get","outputs":[{"name":"","type":"bytes32"}],"payable":false,"type":"function"}]"#;
+const SECRETSTORE_ACL_STORAGE_ABI: &'static str = r#"[{"constant":true,"inputs":[{"name":"user","type":"address"},{"name":"document","type":"bytes32"}],"name":"checkPermissions","outputs":[{"name":"","type":"bool"}],"payable":false,"type":"function"}]"#;
 
 fn build_file(name: &str, abi: &str, filename: &str) {
 	let code = ::native_contract_generator::generate_module(name, abi).unwrap();
@@ -37,4 +38,5 @@ fn build_file(name: &str, abi: &str, filename: &str) {
 fn main() {
 	build_file("Registry", REGISTRY_ABI, "registry.rs");
 	build_file("ServiceTransactionChecker", SERVICE_TRANSACTION_ABI, "service_transaction.rs");
+	build_file("SecretStoreAclStorage", SECRETSTORE_ACL_STORAGE_ABI, "secretstore_acl_storage.rs");
 }

ethcore/native_contracts/src/lib.rs

@@ -25,6 +25,8 @@ extern crate ethcore_util as util;
 
 mod registry;
 mod service_transaction;
+mod secretstore_acl_storage;
 
 pub use self::registry::Registry;
 pub use self::service_transaction::ServiceTransactionChecker;
+pub use self::secretstore_acl_storage::SecretStoreAclStorage;

ethcore/native_contracts/src/secretstore_acl_storage.rs

@@ -0,0 +1,22 @@
+// Copyright 2015-2017 Parity Technologies (UK) Ltd.
+// This file is part of Parity.
+
+// Parity is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// Parity is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with Parity.  If not, see <http://www.gnu.org/licenses/>.
+
+#![allow(unused_mut, unused_variables, unused_imports)]
+
+//! Secret store ACL storage contract.
+// TODO: testing.
+
+include!(concat!(env!("OUT_DIR"), "/secretstore_acl_storage.rs"));

parity/run.rs

@@ -463,7 +463,9 @@ pub fn execute(cmd: RunCmd, can_restart: bool, logger: Arc<RotatingLogger>) -> R
 	let signer_server = signer::start(cmd.signer_conf.clone(), signer_deps)?;
 
 	// secret store key server
-	let secretstore_deps = secretstore::Dependencies { };
+	let secretstore_deps = secretstore::Dependencies {
+		client: client.clone(),
+	};
 	let secretstore_key_server = secretstore::start(cmd.secretstore_conf.clone(), secretstore_deps);
 
 	// the ipfs server

parity/secretstore.rs

@@ -14,7 +14,9 @@
 // You should have received a copy of the GNU General Public License
 // along with Parity.  If not, see <http://www.gnu.org/licenses/>.
 
+use std::sync::Arc;
 use dir::default_data_path;
+use ethcore::client::Client;
 use helpers::replace_home;
 
 #[derive(Debug, PartialEq, Clone)]
@@ -30,10 +32,10 @@ pub struct Configuration {
 	pub data_path: String,
 }
 
-#[derive(Debug, PartialEq, Clone)]
 /// Secret store dependencies
 pub struct Dependencies {
-	// the only dependency will be BlockChainClient
+	/// Blockchain client.
+	pub client: Arc<Client>,
 }
 
 #[cfg(not(feature = "secretstore"))]
@@ -64,7 +66,7 @@ mod server {
 
 	impl KeyServer {
 		/// Create new key server
-		pub fn new(conf: Configuration, _deps: Dependencies) -> Result<Self, String> {
+		pub fn new(conf: Configuration, deps: Dependencies) -> Result<Self, String> {
 			let key_pairs = vec![
 				ethkey::KeyPair::from_secret("6c26a76e9b31048d170873a791401c7e799a11f0cefc0171cc31a49800967509".parse().unwrap()).unwrap(),
 				ethkey::KeyPair::from_secret("7e94018b3731afdb3b4e6f4c3e179475640166da12e1d1b0c7d80729b1a5b452".parse().unwrap()).unwrap(),
@@ -96,7 +98,7 @@ mod server {
 				}
 			};
 
-			let key_server = ethcore_secretstore::start(conf)
+			let key_server = ethcore_secretstore::start(deps.client, conf)
 				.map_err(Into::<String>::into)?;
 
 			Ok(KeyServer {

secret_store/Cargo.toml

@@ -24,12 +24,15 @@ tokio-core = "0.1"
 tokio-service = "0.1"
 tokio-proto = "0.1"
 url = "1.0"
+ethabi = "1.0.0"
+ethcore = { path = "../ethcore" }
 ethcore-devtools = { path = "../devtools" }
 ethcore-util = { path = "../util" }
 ethcore-ipc = { path = "../ipc/rpc" }
 ethcore-ipc-nano = { path = "../ipc/nano" }
 ethcrypto = { path = "../ethcrypto" }
 ethkey = { path = "../ethkey" }
+native-contracts = { path = "../ethcore/native_contracts" }
 
 [profile.release]
 debug = true

secret_store/src/acl_storage.rs

@@ -14,38 +14,92 @@
 // You should have received a copy of the GNU General Public License
 // along with Parity.  If not, see <http://www.gnu.org/licenses/>.
 
-use std::collections::{HashMap, HashSet};
-use parking_lot::RwLock;
+use std::sync::Arc;
+use futures::{future, Future};
+use parking_lot::Mutex;
+use ethkey::public_to_address;
+use ethcore::client::{Client, BlockChainClient, BlockId};
+use native_contracts::SecretStoreAclStorage;
 use types::all::{Error, DocumentAddress, Public};
 
+const ACL_CHECKER_CONTRACT_REGISTRY_NAME: &'static str = "secretstore_acl_checker";
+
 /// ACL storage of Secret Store
 pub trait AclStorage: Send + Sync {
 	/// Check if requestor with `public` key can access document with hash `document`
 	fn check(&self, public: &Public, document: &DocumentAddress) -> Result<bool, Error>;
 }
 
-/// Dummy ACL storage implementation
-#[derive(Default, Debug)]
-pub struct DummyAclStorage {
-	prohibited: RwLock<HashMap<Public, HashSet<DocumentAddress>>>,
+/// On-chain ACL storage implementation.
+pub struct OnChainAclStorage {
+	/// Blockchain client.
+	client: Arc<Client>,
+	/// On-chain contract.
+	contract: Mutex<Option<SecretStoreAclStorage>>,
 }
 
-impl DummyAclStorage {
-	#[cfg(test)]
-	/// Prohibit given requestor access to given document
-	pub fn prohibit(&self, public: Public, document: DocumentAddress) {
-		self.prohibited.write()
-			.entry(public)
-			.or_insert_with(Default::default)
-			.insert(document);
+impl OnChainAclStorage {
+	pub fn new(client: Arc<Client>) -> Self {
+		OnChainAclStorage {
+			client: client,
+			contract: Mutex::new(None),
+		}
 	}
 }
 
-impl AclStorage for DummyAclStorage {
+impl AclStorage for OnChainAclStorage {
 	fn check(&self, public: &Public, document: &DocumentAddress) -> Result<bool, Error> {
-		Ok(self.prohibited.read()
-			.get(public)
-			.map(|docs| !docs.contains(document))
-			.unwrap_or(true))
+		let mut contract = self.contract.lock();
+		if !contract.is_some() {
+			*contract = self.client.registry_address(ACL_CHECKER_CONTRACT_REGISTRY_NAME.to_owned())
+				.and_then(|contract_addr| {
+					trace!(target: "secretstore", "Configuring for ACL checker contract from {}", contract_addr);
+
+					Some(SecretStoreAclStorage::new(contract_addr))
+				})
+		}
+		if let Some(ref contract) = *contract {
+			let address = public_to_address(&public);
+			let do_call = |a, d| future::done(self.client.call_contract(BlockId::Latest, a, d));
+			contract.check_permissions(do_call, address, document.clone())
+				.map_err(|err| Error::Internal(err))
+				.wait()
+		} else {
+			Err(Error::Internal("ACL checker contract is not configured".to_owned()))
+		}
+	}
+}
+
+#[cfg(test)]
+pub mod tests {
+	use std::collections::{HashMap, HashSet};
+	use parking_lot::RwLock;
+	use types::all::{Error, DocumentAddress, Public};
+	use super::AclStorage;
+
+	#[derive(Default, Debug)]
+	/// Dummy ACL storage implementation
+	pub struct DummyAclStorage {
+		prohibited: RwLock<HashMap<Public, HashSet<DocumentAddress>>>,
+	}
+
+	impl DummyAclStorage {
+		#[cfg(test)]
+		/// Prohibit given requestor access to given document
+		pub fn prohibit(&self, public: Public, document: DocumentAddress) {
+			self.prohibited.write()
+				.entry(public)
+				.or_insert_with(Default::default)
+				.insert(document);
+		}
+	}
+
+	impl AclStorage for DummyAclStorage {
+		fn check(&self, public: &Public, document: &DocumentAddress) -> Result<bool, Error> {
+			Ok(self.prohibited.read()
+				.get(public)
+				.map(|docs| !docs.contains(document))
+				.unwrap_or(true))
+		}
 	}
 }

secret_store/src/key_server.rs

@@ -147,7 +147,7 @@ mod tests {
 	use std::sync::Arc;
 	use ethcrypto;
 	use ethkey::{self, Random, Generator};
-	use acl_storage::DummyAclStorage;
+	use acl_storage::tests::DummyAclStorage;
 	use key_storage::tests::DummyKeyStorage;
 	use types::all::{ClusterConfiguration, NodeAddress, EncryptionConfiguration, DocumentEncryptedKey, DocumentKey};
 	use super::super::{RequestSignature, DocumentAddress};

secret_store/src/key_server_cluster/decryption_session.rs

@@ -220,7 +220,7 @@ impl SessionImpl {
 				self.completed.notify_all();
 			},
 			// we can not decrypt data
-			SessionState::Failed => (),
+			SessionState::Failed => self.completed.notify_all(),
 			// cannot reach other states
 			_ => unreachable!("process_initialization_response can change state to WaitingForPartialDecryption or Failed; checked that we are in WaitingForInitializationConfirm state above; qed"),
 		}
@@ -285,7 +285,10 @@ impl SessionImpl {
 			SessionState::WaitingForPartialDecryption =>
 				SessionImpl::start_waiting_for_partial_decryption(self.node().clone(), self.id.clone(), self.access_key.clone(), &self.cluster, &self.encrypted_data, &mut *data),
 			// we can not have enough nodes for decryption
-			SessionState::Failed => Ok(()),
+			SessionState::Failed => {
+				self.completed.notify_all();
+				Ok(())
+			},
 			// cannot reach other states
 			_ => unreachable!("process_initialization_response can change state to WaitingForPartialDecryption or Failed; checked that we are in WaitingForInitializationConfirm state above; qed"),
 		}
@@ -480,6 +483,7 @@ fn process_initialization_response(encrypted_data: &DocumentKeyShare, data: &mut
 
 			// check if we still can receive enough confirmations to do a decryption?
 			if encrypted_data.id_numbers.len() - data.rejected_nodes.len() < encrypted_data.threshold + 1 {
+				data.decrypted_secret = Some(Err(Error::AccessDenied));
 				data.state = SessionState::Failed;
 			}
 		},
@@ -503,7 +507,7 @@ fn do_partial_decryption(node: &NodeId, _requestor_public: &Public, participants
 mod tests {
 	use std::sync::Arc;
 	use std::collections::BTreeMap;
-	use super::super::super::acl_storage::DummyAclStorage;
+	use super::super::super::acl_storage::tests::DummyAclStorage;
 	use ethkey::{self, Random, Generator, Public, Secret};
 	use key_server_cluster::{NodeId, DocumentKeyShare, SessionId, Error};
 	use key_server_cluster::cluster::tests::DummyCluster;

secret_store/src/key_server_cluster/mod.rs

@@ -21,7 +21,7 @@ use ethcrypto;
 use super::types::all::DocumentAddress;
 
 pub use super::types::all::{NodeId, EncryptionConfiguration};
-pub use super::acl_storage::{AclStorage, DummyAclStorage};
+pub use super::acl_storage::AclStorage;
 pub use super::key_storage::{KeyStorage, DocumentKeyShare};
 pub use super::serialization::{SerializableSignature, SerializableH256, SerializableSecret, SerializablePublic};
 pub use self::cluster::{ClusterCore, ClusterConfiguration, ClusterClient};
@@ -30,6 +30,8 @@ pub use self::decryption_session::Session as DecryptionSession;
 
 #[cfg(test)]
 pub use super::key_storage::tests::DummyKeyStorage;
+#[cfg(test)]
+pub use super::acl_storage::tests::DummyAclStorage;
 
 pub type SessionId = DocumentAddress;
 
@@ -72,6 +74,8 @@ pub enum Error {
 	Serde(String),
 	/// Key storage error.
 	KeyStorage(String),
+	/// Acl storage error.
+	AccessDenied,
 }
 
 impl From<ethkey::Error> for Error {
@@ -110,6 +114,7 @@ impl fmt::Display for Error {
 			Error::Io(ref e) => write!(f, "i/o error {}", e),
 			Error::Serde(ref e) => write!(f, "serde error {}", e),
 			Error::KeyStorage(ref e) => write!(f, "key storage error {}", e),
+			Error::AccessDenied => write!(f, "Access denied"),
 		}
 	}
 }

secret_store/src/lib.rs

@@ -32,11 +32,14 @@ extern crate tokio_service;
 extern crate tokio_proto;
 extern crate url;
 
+extern crate ethabi;
+extern crate ethcore;
 extern crate ethcore_devtools as devtools;
 extern crate ethcore_util as util;
 extern crate ethcore_ipc as ipc;
 extern crate ethcrypto;
 extern crate ethkey;
+extern crate native_contracts;
 
 mod key_server_cluster;
 mod types;
@@ -52,15 +55,18 @@ mod key_server;
 mod key_storage;
 mod serialization;
 
+use std::sync::Arc;
+use ethcore::client::Client;
+
 pub use types::all::{DocumentAddress, DocumentKey, DocumentEncryptedKey, RequestSignature, Public,
 	Error, NodeAddress, ServiceConfiguration, ClusterConfiguration, EncryptionConfiguration};
 pub use traits::{KeyServer};
 
 /// Start new key server instance
-pub fn start(config: ServiceConfiguration) -> Result<Box<KeyServer>, Error> {
+pub fn start(client: Arc<Client>, config: ServiceConfiguration) -> Result<Box<KeyServer>, Error> {
 	use std::sync::Arc;
 
-	let acl_storage = Arc::new(acl_storage::DummyAclStorage::default());
+	let acl_storage = Arc::new(acl_storage::OnChainAclStorage::new(client));
 	let key_storage = Arc::new(key_storage::PersistentKeyStorage::new(&config)?);
 	let key_server = key_server::KeyServerImpl::new(&config.cluster_config, acl_storage, key_storage)?;
 	let listener = http_listener::KeyServerHttpListener::start(config, key_server)?;

secret_store/src/types/all.rs

@@ -119,7 +119,10 @@ impl From<ethkey::Error> for Error {
 
 impl From<key_server_cluster::Error> for Error {
 	fn from(err: key_server_cluster::Error) -> Self {
-		Error::Internal(err.into())
+		match err {
+			key_server_cluster::Error::AccessDenied => Error::AccessDenied,
+			_ => Error::Internal(err.into()),
+		}
 	}
 }