SecretStore: merge two types of errors into single one + Error::is_non_fatal

secret_store/src/acl_storage.rs

@@ -21,7 +21,7 @@ use ethcore::client::{BlockId, ChainNotify, CallContract, RegistryInfo};
 use ethereum_types::{H256, Address};
 use bytes::Bytes;
 use trusted_client::TrustedClient;
-use types::all::{Error, ServerKeyId};
+use types::{Error, ServerKeyId};
 
 use_contract!(acl_storage, "AclStorage", "res/acl_storage.json");
 
@@ -112,7 +112,7 @@ impl CachedContract {
 					self.contract.functions()
 						.check_permissions()
 						.call(requester, document.clone(), &do_call)
-						.map_err(|e| Error::Internal(e.to_string()))
+						.map_err(|e| Error::Internal(format!("ACL checker call error: {}", e.to_string())))
 				},
 				None => Err(Error::Internal("ACL checker contract is not configured".to_owned())),
 			}

secret_store/src/key_server.rs

@@ -27,7 +27,7 @@ use super::key_storage::KeyStorage;
 use super::key_server_set::KeyServerSet;
 use key_server_cluster::{math, ClusterCore};
 use traits::{AdminSessionsServer, ServerKeyGenerator, DocumentKeyServer, MessageSigner, KeyServer, NodeKeyPair};
-use types::all::{Error, Public, RequestSignature, Requester, ServerKeyId, EncryptedDocumentKey, EncryptedDocumentKeyShadow,
+use types::{Error, Public, RequestSignature, Requester, ServerKeyId, EncryptedDocumentKey, EncryptedDocumentKeyShadow,
 	ClusterConfiguration, MessageHash, EncryptedMessageSignature, NodeId};
 use key_server_cluster::{ClusterClient, ClusterConfiguration as NetClusterConfiguration};
 
@@ -238,7 +238,7 @@ pub mod tests {
 	use key_server_set::tests::MapKeyServerSet;
 	use key_server_cluster::math;
 	use ethereum_types::{H256, H520};
-	use types::all::{Error, Public, ClusterConfiguration, NodeAddress, RequestSignature, ServerKeyId,
+	use types::{Error, Public, ClusterConfiguration, NodeAddress, RequestSignature, ServerKeyId,
 		EncryptedDocumentKey, EncryptedDocumentKeyShadow, MessageHash, EncryptedMessageSignature,
 		Requester, NodeId};
 	use traits::{AdminSessionsServer, ServerKeyGenerator, DocumentKeyServer, MessageSigner, KeyServer};

secret_store/src/key_server_cluster/admin_sessions/key_version_negotiation_session.rs

@@ -143,6 +143,10 @@ pub struct FastestResultComputer {
 	self_node_id: NodeId,
 	/// Threshold (if known).
 	threshold: Option<usize>,
+	/// Count of all configured key server nodes.
+	configured_nodes_count: usize,
+	/// Count of all connected key server nodes.
+	connected_nodes_count: usize,
 }
 
 /// Selects version with most support, waiting for responses from all nodes.
@@ -185,7 +189,7 @@ impl<T> SessionImpl<T> where T: SessionTransport {
 	/// Return result computer reference.
 	pub fn version_holders(&self, version: &H256) -> Result<BTreeSet<NodeId>, Error> {
 		Ok(self.data.lock().versions.as_ref().ok_or(Error::InvalidStateForRequest)?
-			.get(version).ok_or(Error::KeyStorage("key version not found".into()))?
+			.get(version).ok_or(Error::ServerKeyIsNotFound)?
 			.clone())
 	}
 
@@ -236,7 +240,7 @@ impl<T> SessionImpl<T> where T: SessionTransport {
 		// try to complete session
 		Self::try_complete(&self.core, &mut *data);
 		if no_confirmations_required && data.state != SessionState::Finished {
-			return Err(Error::MissingKeyShare);
+			return Err(Error::ServerKeyIsNotFound);
 		} else if data.state == SessionState::Finished {
 			return Ok(());
 		}
@@ -266,7 +270,7 @@ impl<T> SessionImpl<T> where T: SessionTransport {
 			&KeyVersionNegotiationMessage::KeyVersions(ref message) =>
 				self.on_key_versions(sender, message),
 			&KeyVersionNegotiationMessage::KeyVersionsError(ref message) => {
-				self.on_session_error(sender, Error::Io(message.error.clone()));
+				self.on_session_error(sender, message.error.clone());
 				Ok(())
 			},
 		}
@@ -388,7 +392,7 @@ impl<T> ClusterSession for SessionImpl<T> where T: SessionTransport {
 			if data.state != SessionState::Finished {
 				warn!("{}: key version negotiation session failed with timeout", self.core.meta.self_node_id);
 
-				data.result = Some(Err(Error::ConsensusUnreachable));
+				data.result = Some(Err(Error::ConsensusTemporaryUnreachable));
 				self.core.completed.notify_all();
 			}
 		}
@@ -431,19 +435,21 @@ impl SessionTransport for IsolatedSessionTransport {
 }
 
 impl FastestResultComputer {
-	pub fn new(self_node_id: NodeId, key_share: Option<&DocumentKeyShare>) -> Self {
+	pub fn new(self_node_id: NodeId, key_share: Option<&DocumentKeyShare>, configured_nodes_count: usize, connected_nodes_count: usize) -> Self {
 		let threshold = key_share.map(|ks| ks.threshold);
 		FastestResultComputer {
-			self_node_id: self_node_id,
-			threshold: threshold,
+			self_node_id,
+			threshold,
+			configured_nodes_count,
+			connected_nodes_count,
 		}
 	}}
 
 impl SessionResultComputer for FastestResultComputer {
 	fn compute_result(&self, threshold: Option<usize>, confirmations: &BTreeSet<NodeId>, versions: &BTreeMap<H256, BTreeSet<NodeId>>) -> Option<Result<(H256, NodeId), Error>> {
 		match self.threshold.or(threshold) {
 			// if there's no versions at all && we're not waiting for confirmations anymore
-			_ if confirmations.is_empty() && versions.is_empty() => Some(Err(Error::MissingKeyShare)),
+			_ if confirmations.is_empty() && versions.is_empty() => Some(Err(Error::ServerKeyIsNotFound)),
 			// if we have key share on this node
 			Some(threshold) => {
 				// select version this node have, with enough participants
@@ -459,7 +465,17 @@ impl SessionResultComputer for FastestResultComputer {
 						.find(|&(_, ref n)| n.len() >= threshold + 1)
 						.map(|(version, nodes)| Ok((version.clone(), nodes.iter().cloned().nth(0)
 							.expect("version is only inserted when there's at least one owner; qed"))))
-						.unwrap_or(Err(Error::ConsensusUnreachable))),
+						// if there's no version consensus among all connected nodes
+						//   AND we're connected to ALL configured nodes
+						//   OR there are less than required nodes for key restore
+						//     => this means that we can't restore key with CURRENT configuration => respond with fatal error
+						// otherwise we could try later, after all nodes are connected
+						.unwrap_or_else(|| Err(if self.configured_nodes_count == self.connected_nodes_count
+							|| self.configured_nodes_count < threshold + 1 {
+							Error::ConsensusUnreachable
+						} else {
+							Error::ConsensusTemporaryUnreachable
+						}))),
 				}
 			},
 			// if we do not have share, then wait for all confirmations
@@ -469,7 +485,11 @@ impl SessionResultComputer for FastestResultComputer {
 				.max_by_key(|&(_, ref n)| n.len())
 				.map(|(version, nodes)| Ok((version.clone(), nodes.iter().cloned().nth(0)
 					.expect("version is only inserted when there's at least one owner; qed"))))
-				.unwrap_or(Err(Error::ConsensusUnreachable))),
+				.unwrap_or_else(|| Err(if self.configured_nodes_count == self.connected_nodes_count {
+					Error::ConsensusUnreachable
+				} else {
+					Error::ConsensusTemporaryUnreachable
+				}))),
 		}
 	}
 }
@@ -480,7 +500,7 @@ impl SessionResultComputer for LargestSupportResultComputer {
 			return None;
 		}
 		if versions.is_empty() {
-			return Some(Err(Error::MissingKeyShare));
+			return Some(Err(Error::ServerKeyIsNotFound));
 		}
 
 		versions.iter()
@@ -552,12 +572,15 @@ mod tests {
 								id: Default::default(),
 								self_node_id: node_id.clone(),
 								master_node_id: master_node_id.clone(),
+								configured_nodes_count: nodes.len(),
+								connected_nodes_count: nodes.len(),
 							},
 							sub_session: sub_sesion.clone(),
 							key_share: key_storage.get(&Default::default()).unwrap(),
 							result_computer: Arc::new(FastestResultComputer::new(
 								node_id.clone(),
 								key_storage.get(&Default::default()).unwrap().as_ref(),
+								nodes.len(), nodes.len()
 							)),
 							transport: DummyTransport {
 								cluster: cluster,
@@ -723,13 +746,15 @@ mod tests {
 		let computer = FastestResultComputer {
 			self_node_id: Default::default(),
 			threshold: None,
+			configured_nodes_count: 1,
+			connected_nodes_count: 1,
 		};
-		assert_eq!(computer.compute_result(Some(10), &Default::default(), &Default::default()), Some(Err(Error::MissingKeyShare)));
+		assert_eq!(computer.compute_result(Some(10), &Default::default(), &Default::default()), Some(Err(Error::ServerKeyIsNotFound)));
 	}
 
 	#[test]
 	fn largest_computer_returns_missing_share_if_no_versions_returned() {
 		let computer = LargestSupportResultComputer;
-		assert_eq!(computer.compute_result(Some(10), &Default::default(), &Default::default()), Some(Err(Error::MissingKeyShare)));
+		assert_eq!(computer.compute_result(Some(10), &Default::default(), &Default::default()), Some(Err(Error::ServerKeyIsNotFound)));
 	}
 }

secret_store/src/key_server_cluster/admin_sessions/mod.rs

@@ -32,6 +32,10 @@ pub struct ShareChangeSessionMeta {
 	pub master_node_id: NodeId,
 	/// Id of node, on which this session is running.
 	pub self_node_id: NodeId,
+	/// Count of all configured key server nodes.
+	pub configured_nodes_count: usize,
+	/// Count of all connected key server nodes.
+	pub connected_nodes_count: usize,
 }
 
 impl ShareChangeSessionMeta {
@@ -42,6 +46,8 @@ impl ShareChangeSessionMeta {
 			master_node_id: self.master_node_id,
 			self_node_id: self.self_node_id,
 			threshold: all_nodes_set_len.checked_sub(1).ok_or(Error::ConsensusUnreachable)?,
+			configured_nodes_count: self.configured_nodes_count,
+			connected_nodes_count: self.connected_nodes_count,
 		})
 	}
 }

secret_store/src/key_server_cluster/admin_sessions/servers_set_change_session.rs

@@ -282,7 +282,7 @@ impl SessionImpl {
 			&ServersSetChangeMessage::ServersSetChangeShareAddMessage(ref message) =>
 				self.on_share_add_message(sender, message),
 			&ServersSetChangeMessage::ServersSetChangeError(ref message) => {
-				self.on_session_error(sender, Error::Io(message.error.clone()));
+				self.on_session_error(sender, message.error.clone());
 				Ok(())
 			},
 			&ServersSetChangeMessage::ServersSetChangeCompleted(ref message) => 
@@ -416,12 +416,14 @@ impl SessionImpl {
 		match &message.message {
 			&KeyVersionNegotiationMessage::RequestKeyVersions(ref message) if sender == &self.core.meta.master_node_id => {
 				let key_id = message.session.clone().into();
-				let key_share = self.core.key_storage.get(&key_id).map_err(|e| Error::KeyStorage(e.into()))?;
+				let key_share = self.core.key_storage.get(&key_id)?;
 				let negotiation_session = KeyVersionNegotiationSessionImpl::new(KeyVersionNegotiationSessionParams {
 					meta: ShareChangeSessionMeta {
 						id: key_id.clone(),
 						self_node_id: self.core.meta.self_node_id.clone(),
 						master_node_id: sender.clone(),
+						configured_nodes_count: self.core.meta.configured_nodes_count,
+						connected_nodes_count: self.core.meta.connected_nodes_count,
 					},
 					sub_session: message.sub_session.clone().into(),
 					key_share: key_share,
@@ -492,7 +494,7 @@ impl SessionImpl {
 
 				// on nodes, holding selected key share version, we could check if master node plan is correct
 				let master_node_id = message.master_node_id.clone().into();
-				if let Some(key_share) = self.core.key_storage.get(&key_id).map_err(|e| Error::KeyStorage(e.into()))? {
+				if let Some(key_share) = self.core.key_storage.get(&key_id)? {
 					let version = message.version.clone().into();
 					if let Ok(key_version) = key_share.version(&version) {
 						let key_share_owners = key_version.id_numbers.keys().cloned().collect();
@@ -660,7 +662,7 @@ impl SessionImpl {
 		if !data.new_nodes_set.as_ref()
 			.expect("new_nodes_set is filled during initialization; session is completed after initialization; qed")
 			.contains(&self.core.meta.self_node_id) {
-			self.core.key_storage.clear().map_err(|e| Error::KeyStorage(e.into()))?;
+			self.core.key_storage.clear()?;
 		}
 
 		data.state = SessionState::Finished;
@@ -709,6 +711,8 @@ impl SessionImpl {
 				id: key_id,
 				self_node_id: core.meta.self_node_id.clone(),
 				master_node_id: master_node_id,
+				configured_nodes_count: core.meta.configured_nodes_count,
+				connected_nodes_count: core.meta.connected_nodes_count,
 			},
 			cluster: core.cluster.clone(),
 			key_storage: core.key_storage.clone(),
@@ -731,12 +735,14 @@ impl SessionImpl {
 					Some(Ok(key_id)) => key_id,
 				};
 
-				let key_share = core.key_storage.get(&key_id).map_err(|e| Error::KeyStorage(e.into()))?;
+				let key_share = core.key_storage.get(&key_id)?;
 				let negotiation_session = KeyVersionNegotiationSessionImpl::new(KeyVersionNegotiationSessionParams {
 					meta: ShareChangeSessionMeta {
 						id: key_id,
 						self_node_id: core.meta.self_node_id.clone(),
 						master_node_id: core.meta.self_node_id.clone(),
+						configured_nodes_count: core.meta.configured_nodes_count,
+						connected_nodes_count: core.meta.connected_nodes_count,
 					},
 					sub_session: math::generate_random_scalar()?,
 					key_share: key_share,
@@ -888,7 +894,7 @@ impl SessionImpl {
 		if !data.new_nodes_set.as_ref()
 			.expect("new_nodes_set is filled during initialization; session is completed after initialization; qed")
 			.contains(&core.meta.self_node_id) {
-			core.key_storage.clear().map_err(|e| Error::KeyStorage(e.into()))?;
+			core.key_storage.clear()?;
 		}
 
 		data.state = SessionState::Finished;
@@ -1011,9 +1017,9 @@ impl KeyVersionNegotiationTransport for ServersSetChangeKeyVersionNegotiationTra
 }
 
 fn check_nodes_set(all_nodes_set: &BTreeSet<NodeId>, new_nodes_set: &BTreeSet<NodeId>) -> Result<(), Error> {
-	// all new nodes must be a part of all nodes set
+	// all_nodes_set is the set of nodes we're currently connected to (and configured for)
 	match new_nodes_set.iter().any(|n| !all_nodes_set.contains(n)) {
-		true => Err(Error::InvalidNodesConfiguration),
+		true => Err(Error::NodeDisconnected),
 		false => Ok(())
 	}
 }
@@ -1104,6 +1110,8 @@ pub mod tests {
 				self_node_id: master_node_id.clone(),
 				master_node_id: master_node_id.clone(),
 				id: SessionId::default(),
+				configured_nodes_count: all_nodes_set.len(),
+				connected_nodes_count: all_nodes_set.len(),
 			};
 
 			let old_nodes = gml.nodes.iter().map(|n| create_node(meta.clone(), admin_public.clone(), all_nodes_set.clone(), n.1));

secret_store/src/key_server_cluster/admin_sessions/share_add_session.rs

@@ -155,9 +155,7 @@ pub struct IsolatedSessionTransport {
 impl<T> SessionImpl<T> where T: SessionTransport {
 	/// Create new share addition session.
 	pub fn new(params: SessionParams<T>) -> Result<Self, Error> {
-		let key_share = params.key_storage
-			.get(&params.meta.id)
-			.map_err(|e| Error::KeyStorage(e.into()))?;
+		let key_share = params.key_storage.get(&params.meta.id)?;
 
 		Ok(SessionImpl {
 			core: SessionCore {
@@ -257,8 +255,8 @@ impl<T> SessionImpl<T> where T: SessionTransport {
 		let admin_public = self.core.admin_public.as_ref().cloned().ok_or(Error::ConsensusUnreachable)?;
 
 		// key share version is required on ShareAdd master node
-		let key_share = self.core.key_share.as_ref().ok_or_else(|| Error::KeyStorage("key share is not found on master node".into()))?;
-		let key_version = key_share.version(&version).map_err(|e| Error::KeyStorage(e.into()))?;
+		let key_share = self.core.key_share.as_ref().ok_or_else(|| Error::ServerKeyIsNotFound)?;
+		let key_version = key_share.version(&version)?;
 
 		// old nodes set is all non-isolated owners of version holders
 		let non_isolated_nodes = self.core.transport.nodes();
@@ -326,7 +324,7 @@ impl<T> SessionImpl<T> where T: SessionTransport {
 			&ShareAddMessage::NewKeysDissemination(ref message) =>
 				self.on_new_keys_dissemination(sender, message),
 			&ShareAddMessage::ShareAddError(ref message) => {
-				self.on_session_error(sender, Error::Io(message.error.clone().into()));
+				self.on_session_error(sender, message.error.clone());
 				Ok(())
 			},
 		}
@@ -714,10 +712,10 @@ impl<T> SessionImpl<T> where T: SessionTransport {
 		// save encrypted data to the key storage
 		data.state = SessionState::Finished;
 		if core.key_share.is_some() {
-			core.key_storage.update(core.meta.id.clone(), refreshed_key_share.clone())
+			core.key_storage.update(core.meta.id.clone(), refreshed_key_share.clone())?;
 		} else {
-			core.key_storage.insert(core.meta.id.clone(), refreshed_key_share.clone())
-		}.map_err(|e| Error::KeyStorage(e.into()))?;
+			core.key_storage.insert(core.meta.id.clone(), refreshed_key_share.clone())?;
+		}
 
 		// signal session completion
 		data.state = SessionState::Finished;
@@ -851,7 +849,7 @@ impl SessionTransport for IsolatedSessionTransport {
 #[cfg(test)]
 pub mod tests {
 	use std::sync::Arc;
-	use std::collections::{VecDeque, BTreeMap, BTreeSet};
+	use std::collections::{VecDeque, BTreeMap, BTreeSet, HashSet};
 	use ethkey::{Random, Generator, Public, KeyPair, Signature, sign};
 	use ethereum_types::H256;
 	use key_server_cluster::{NodeId, SessionId, Error, KeyStorage, DummyKeyStorage};
@@ -952,6 +950,8 @@ pub mod tests {
 				id: SessionId::default(),
 				self_node_id: NodeId::default(),
 				master_node_id: master_node_id,
+				configured_nodes_count: new_nodes_set.iter().chain(old_nodes_set.iter()).collect::<HashSet<_>>().len(),
+				connected_nodes_count: new_nodes_set.iter().chain(old_nodes_set.iter()).collect::<HashSet<_>>().len(),
 			};
 			let new_nodes = new_nodes_set.iter()
 				.filter(|n| !old_nodes_set.contains(&n))
@@ -992,6 +992,8 @@ pub mod tests {
 				id: SessionId::default(),
 				self_node_id: NodeId::default(),
 				master_node_id: master_node_id,
+				configured_nodes_count: new_nodes_set.iter().chain(ml.nodes.keys()).collect::<BTreeSet<_>>().len(),
+				connected_nodes_count: new_nodes_set.iter().chain(ml.nodes.keys()).collect::<BTreeSet<_>>().len(),
 			};
 			let old_nodes_set = ml.nodes.keys().cloned().collect();
 			let nodes = ml.nodes.iter()
@@ -1102,7 +1104,7 @@ pub mod tests {
 		assert_eq!(ml.nodes[&master_node_id].session.initialize(Some(ml.version), Some(new_nodes_set),
 			Some(ml.old_set_signature.clone()),
 			Some(ml.new_set_signature.clone())
-		).unwrap_err(), Error::KeyStorage("key share is not found on master node".into()));
+		).unwrap_err(), Error::ServerKeyIsNotFound);
 	}
 
 	#[test]