openethereum/secret_store/src/key_server_cluster/io/handshake.rs

313 lines
12 KiB
Rust

// 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/>.
use std::io;
use std::collections::BTreeSet;
use futures::{Future, Poll, Async};
use tokio_io::{AsyncRead, AsyncWrite};
use ethkey::{Random, Generator, KeyPair, Secret, sign, verify_public};
use util::H256;
use key_server_cluster::{NodeId, Error};
use key_server_cluster::message::{Message, ClusterMessage, NodePublicKey, NodePrivateKeySignature};
use key_server_cluster::io::{write_message, write_encrypted_message, WriteMessage, ReadMessage,
read_message, read_encrypted_message, compute_shared_key};
/// Start handshake procedure with another node from the cluster.
pub fn handshake<A>(a: A, self_key_pair: KeyPair, trusted_nodes: BTreeSet<NodeId>) -> Handshake<A> where A: AsyncWrite + AsyncRead {
let self_confirmation_plain = Random.generate().map(|kp| *kp.secret().clone()).map_err(Into::into);
handshake_with_plain_confirmation(a, self_confirmation_plain, self_key_pair, trusted_nodes)
}
/// Start handshake procedure with another node from the cluster and given plain confirmation.
pub fn handshake_with_plain_confirmation<A>(a: A, self_confirmation_plain: Result<H256, Error>, self_key_pair: KeyPair, trusted_nodes: BTreeSet<NodeId>) -> Handshake<A> where A: AsyncWrite + AsyncRead {
let (error, state) = match self_confirmation_plain.clone()
.and_then(|c| Handshake::<A>::make_public_key_message(self_key_pair.public().clone(), c)) {
Ok(message) => (None, HandshakeState::SendPublicKey(write_message(a, message))),
Err(err) => (Some((a, Err(err))), HandshakeState::Finished),
};
Handshake {
is_active: true,
error: error,
state: state,
self_key_pair: self_key_pair,
self_confirmation_plain: self_confirmation_plain.unwrap_or(Default::default()),
trusted_nodes: trusted_nodes,
other_node_id: None,
other_confirmation_plain: None,
shared_key: None,
}
}
/// Wait for handshake procedure to be started by another node from the cluster.
pub fn accept_handshake<A>(a: A, self_key_pair: KeyPair, trusted_nodes: BTreeSet<NodeId>) -> Handshake<A> where A: AsyncWrite + AsyncRead {
let self_confirmation_plain = Random.generate().map(|kp| *kp.secret().clone()).map_err(Into::into);
let (error, state) = match self_confirmation_plain.clone() {
Ok(_) => (None, HandshakeState::ReceivePublicKey(read_message(a))),
Err(err) => (Some((a, Err(err))), HandshakeState::Finished),
};
Handshake {
is_active: false,
error: error,
state: state,
self_key_pair: self_key_pair,
self_confirmation_plain: self_confirmation_plain.unwrap_or(Default::default()),
trusted_nodes: trusted_nodes,
other_node_id: None,
other_confirmation_plain: None,
shared_key: None,
}
}
#[derive(Debug, PartialEq)]
/// Result of handshake procedure.
pub struct HandshakeResult {
/// Node id.
pub node_id: NodeId,
/// Shared key.
pub shared_key: KeyPair,
}
/// Future handshake procedure.
pub struct Handshake<A> {
is_active: bool,
error: Option<(A, Result<HandshakeResult, Error>)>,
state: HandshakeState<A>,
self_key_pair: KeyPair,
self_confirmation_plain: H256,
trusted_nodes: BTreeSet<NodeId>,
other_node_id: Option<NodeId>,
other_confirmation_plain: Option<H256>,
shared_key: Option<KeyPair>,
}
/// Active handshake state.
enum HandshakeState<A> {
SendPublicKey(WriteMessage<A>),
ReceivePublicKey(ReadMessage<A>),
SendPrivateKeySignature(WriteMessage<A>),
ReceivePrivateKeySignature(ReadMessage<A>),
Finished,
}
impl<A> Handshake<A> where A: AsyncRead + AsyncWrite {
#[cfg(test)]
pub fn set_self_confirmation_plain(&mut self, self_confirmation_plain: H256) {
self.self_confirmation_plain = self_confirmation_plain;
}
pub fn make_public_key_message(self_node_id: NodeId, confirmation_plain: H256) -> Result<Message, Error> {
Ok(Message::Cluster(ClusterMessage::NodePublicKey(NodePublicKey {
node_id: self_node_id.into(),
confirmation_plain: confirmation_plain.into(),
})))
}
fn make_private_key_signature_message(secret: &Secret, confirmation_plain: &H256) -> Result<Message, Error> {
Ok(Message::Cluster(ClusterMessage::NodePrivateKeySignature(NodePrivateKeySignature {
confirmation_signed: sign(secret, confirmation_plain)?.into(),
})))
}
}
impl<A> Future for Handshake<A> where A: AsyncRead + AsyncWrite {
type Item = (A, Result<HandshakeResult, Error>);
type Error = io::Error;
fn poll(&mut self) -> Poll<Self::Item, Self::Error> {
if let Some(error_result) = self.error.take() {
return Ok(error_result.into());
}
let (next, result) = match self.state {
HandshakeState::SendPublicKey(ref mut future) => {
let (stream, _) = try_ready!(future.poll());
if self.is_active {
(HandshakeState::ReceivePublicKey(
read_message(stream)
), Async::NotReady)
} else {
self.shared_key = match compute_shared_key(self.self_key_pair.secret(),
self.other_node_id.as_ref().expect("we are in passive mode; in passive mode SendPublicKey follows ReceivePublicKey; other_node_id is filled in ReceivePublicKey; qed")
) {
Ok(shared_key) => Some(shared_key),
Err(err) => return Ok((stream, Err(err)).into()),
};
let message = match Handshake::<A>::make_private_key_signature_message(
self.self_key_pair.secret(),
self.other_confirmation_plain.as_ref().expect("we are in passive mode; in passive mode SendPublicKey follows ReceivePublicKey; other_confirmation_plain is filled in ReceivePublicKey; qed")
) {
Ok(message) => message,
Err(err) => return Ok((stream, Err(err)).into()),
};
(HandshakeState::SendPrivateKeySignature(write_encrypted_message(stream,
self.shared_key.as_ref().expect("filled couple of lines above; qed"),
message)), Async::NotReady)
}
},
HandshakeState::ReceivePublicKey(ref mut future) => {
let (stream, message) = try_ready!(future.poll());
let message = match message {
Ok(message) => match message {
Message::Cluster(ClusterMessage::NodePublicKey(message)) => message,
_ => return Ok((stream, Err(Error::InvalidMessage)).into()),
},
Err(err) => return Ok((stream, Err(err.into())).into()),
};
if !self.trusted_nodes.contains(&*message.node_id) {
return Ok((stream, Err(Error::InvalidNodeId)).into());
}
self.other_node_id = Some(message.node_id.into());
self.other_confirmation_plain = Some(message.confirmation_plain.into());
if self.is_active {
self.shared_key = match compute_shared_key(self.self_key_pair.secret(),
self.other_node_id.as_ref().expect("filled couple of lines above; qed")
) {
Ok(shared_key) => Some(shared_key),
Err(err) => return Ok((stream, Err(err)).into()),
};
let message = match Handshake::<A>::make_private_key_signature_message(
self.self_key_pair.secret(),
self.other_confirmation_plain.as_ref().expect("filled couple of lines above; qed")
) {
Ok(message) => message,
Err(err) => return Ok((stream, Err(err)).into()),
};
(HandshakeState::SendPrivateKeySignature(write_encrypted_message(stream,
self.shared_key.as_ref().expect("filled couple of lines above; qed"),
message)), Async::NotReady)
} else {
let message = match Handshake::<A>::make_public_key_message(self.self_key_pair.public().clone(), self.self_confirmation_plain.clone()) {
Ok(message) => message,
Err(err) => return Ok((stream, Err(err)).into()),
};
(HandshakeState::SendPublicKey(write_message(stream, message)), Async::NotReady)
}
},
HandshakeState::SendPrivateKeySignature(ref mut future) => {
let (stream, _) = try_ready!(future.poll());
(HandshakeState::ReceivePrivateKeySignature(
read_encrypted_message(stream,
self.shared_key.as_ref().expect("shared_key is filled in Send/ReceivePublicKey; SendPrivateKeySignature follows Send/ReceivePublicKey; qed").clone()
)
), Async::NotReady)
},
HandshakeState::ReceivePrivateKeySignature(ref mut future) => {
let (stream, message) = try_ready!(future.poll());
let message = match message {
Ok(message) => match message {
Message::Cluster(ClusterMessage::NodePrivateKeySignature(message)) => message,
_ => return Ok((stream, Err(Error::InvalidMessage)).into()),
},
Err(err) => return Ok((stream, Err(err.into())).into()),
};
let other_node_public = self.other_node_id.as_ref().expect("other_node_id is filled in ReceivePublicKey; ReceivePrivateKeySignature follows ReceivePublicKey; qed");
if !verify_public(other_node_public, &*message.confirmation_signed, &self.self_confirmation_plain).unwrap_or(false) {
return Ok((stream, Err(Error::InvalidMessage)).into());
}
(HandshakeState::Finished, Async::Ready((stream, Ok(HandshakeResult {
node_id: self.other_node_id.expect("other_node_id is filled in ReceivePublicKey; ReceivePrivateKeySignature follows ReceivePublicKey; qed"),
shared_key: self.shared_key.clone().expect("shared_key is filled in Send/ReceivePublicKey; ReceivePrivateKeySignature follows Send/ReceivePublicKey; qed"),
}))))
},
HandshakeState::Finished => panic!("poll Handshake after it's done"),
};
self.state = next;
match result {
// by polling again, we register new future
Async::NotReady => self.poll(),
result => Ok(result)
}
}
}
#[cfg(test)]
mod tests {
use std::collections::BTreeSet;
use futures::Future;
use ethkey::{Random, Generator, sign};
use util::H256;
use key_server_cluster::io::message::compute_shared_key;
use key_server_cluster::io::message::tests::TestIo;
use key_server_cluster::message::{Message, ClusterMessage, NodePublicKey, NodePrivateKeySignature};
use super::{handshake_with_plain_confirmation, accept_handshake, HandshakeResult};
fn prepare_test_io() -> (H256, TestIo) {
let self_key_pair = Random.generate().unwrap();
let peer_key_pair = Random.generate().unwrap();
let mut io = TestIo::new(self_key_pair.clone(), peer_key_pair.public().clone());
let self_confirmation_plain = *Random.generate().unwrap().secret().clone();
let peer_confirmation_plain = *Random.generate().unwrap().secret().clone();
let self_confirmation_signed = sign(peer_key_pair.secret(), &self_confirmation_plain).unwrap();
io.add_input_message(Message::Cluster(ClusterMessage::NodePublicKey(NodePublicKey {
node_id: peer_key_pair.public().clone().into(),
confirmation_plain: peer_confirmation_plain.into(),
})));
io.add_encrypted_input_message(Message::Cluster(ClusterMessage::NodePrivateKeySignature(NodePrivateKeySignature {
confirmation_signed: self_confirmation_signed.into(),
})));
(self_confirmation_plain, io)
}
#[test]
fn active_handshake_works() {
let (self_confirmation_plain, io) = prepare_test_io();
let self_key_pair = io.self_key_pair().clone();
let trusted_nodes: BTreeSet<_> = vec![io.peer_public().clone()].into_iter().collect();
let shared_key = compute_shared_key(self_key_pair.secret(), trusted_nodes.iter().nth(0).unwrap()).unwrap();
let handshake = handshake_with_plain_confirmation(io, Ok(self_confirmation_plain), self_key_pair, trusted_nodes);
let handshake_result = handshake.wait().unwrap();
assert_eq!(handshake_result.1, Ok(HandshakeResult {
node_id: handshake_result.0.peer_public().clone(),
shared_key: shared_key,
}));
}
#[test]
fn passive_handshake_works() {
let (self_confirmation_plain, io) = prepare_test_io();
let self_key_pair = io.self_key_pair().clone();
let trusted_nodes: BTreeSet<_> = vec![io.peer_public().clone()].into_iter().collect();
let shared_key = compute_shared_key(self_key_pair.secret(), trusted_nodes.iter().nth(0).unwrap()).unwrap();
let mut handshake = accept_handshake(io, self_key_pair, trusted_nodes);
handshake.set_self_confirmation_plain(self_confirmation_plain);
let handshake_result = handshake.wait().unwrap();
assert_eq!(handshake_result.1, Ok(HandshakeResult {
node_id: handshake_result.0.peer_public().clone(),
shared_key: shared_key,
}));
}
}