Commit introducing Client keyexchange, triggering bugs.

Clients now send their public key to each node and the node calculates
the shared secret. The node does not yet respond with it's public key.
To keep this commit smaller.

Nodes now disconnect from each other in a better way.

Getting the relevant crypto api is now done with a generic function.
What crypto algorithm and implemenation is beign used can be selected in
the cmake cache (use cmake-gui or ccmake)

Clients now connect correctly to multiple nodes.

5 files changed, 89 insertions, 19 deletions

diff --git a/client/cmixclient.cpp b/client/cmixclient.cpp
index e3f5ac4..195c5e0 100644
--- a/client/cmixclient.cpp
+++ b/client/cmixclient.cpp
@@ -1,38 +1,86 @@
 
 #include "cmixclient.hpp"
 
-void CMixClient::initialized() {
-	BOOST_LOG_TRIVIAL(trace) << "Client connections were made";
-	for(auto&& connection : network_connections) {
-		cmix_proto::Bye bye;
-		connection.send(bye);
-	}
-	io_service.stop();
+void CMixClient::key_exchange(int i) {
+	shared_keys.resize(network_connections.size());
+		
+	cmix_proto::KeyExchange ke;
+	ke.set_public_key(keypair.pub, keypair.pub_len);
+		
+	network_connections[i].send(ke);
+		
+	cmix_proto::Bye bye;
+	network_connections[i].send(bye);
 }
 
 void CMixClient::initialize_connections() {
 	network_connections.reserve(network_details.size());
 	
-	int i = network_details.size();
-	auto handler = [this, i]() mutable {
-		cmix_proto::ImAClient imaclient;
-		network_connections.at(network_details.size() - i).send(imaclient);
+	for(int i = 0; i < network_details.size(); ++i) {
+		auto handler = [this, i]() mutable {
+			cmix_proto::ImAClient imaclient;
+			BOOST_LOG_TRIVIAL(trace) << "sending imaclient to node: " << i;
+			network_connections.at(i).send(imaclient);
 		
-		if(--i == 0) {
-			initialized();
-		}
-	};
+			key_exchange(i);
+		};
 	
-	for(auto&& details : network_details) {
 		network_connections.emplace_back(boost::asio::ip::tcp::socket(io_service));
-		network_connections.back().async_connect(details.host, details.port, handler);
+		network_connections.back().async_connect(network_details[i].host, network_details[i].port, handler);
+	
+	}
+}
+
+cmix_proto::CMixMessage CMixClient::parse_cmix_message(std::vector<uint8_t> const& buffer)
+{
+	cmix_proto::CMixMessage message;
+	if(!message.ParseFromArray(buffer.data(), buffer.size())) {
+		BOOST_LOG_TRIVIAL(error) << "Received something which was not a CMixMessage";
+		throw std::runtime_error("Network communication was disrupted in a unrecoverable way.");
+	}
+	return message;
+}
+
+void CMixClient::handle_key_exchange(int node_id, cmix_proto::KeyExchange const& ke)
+{
+	shared_keys[node_id] = api.derive_shared_key(keypair, reinterpret_cast<uint8_t const*>(ke.public_key().c_str()), false);
+}
+
+void CMixClient::handle_message(int node_id, std::vector<uint8_t> const& message_buffer)
+{
+	cmix_proto::CMixMessage message;
+	try {
+		message = parse_cmix_message(message_buffer);
+	} catch(std::runtime_error const& e) {
+		for(auto&& connection : network_connections) {
+			connection.close();
+		}
+		io_service.stop();
+		return;
+	}
+	
+	switch(message.contents_case()) {
+		case cmix_proto::CMixMessage::ContentsCase::kKeyexchange: {
+			handle_key_exchange(node_id, *message.mutable_keyexchange());
+			return;
+		}
+		default: {
+			BOOST_LOG_TRIVIAL(error) << "Received unknown message";
+		}
 	}
+	
+	for(auto&& connection : network_connections) {
+		connection.close();
+	}
+	io_service.stop();
 }
 
 CMixClient::CMixClient(std::vector<NodeDetails> details)
 : io_service()
 , network_details(details)
 , network_connections()
+, api(get_implementation())
+, keypair(api.create_key_pair())
 {
 	initialize_connections();
 }
diff --git a/client/cmixclient.hpp b/client/cmixclient.hpp
index 10438d1..5c6405a 100644
--- a/client/cmixclient.hpp
+++ b/client/cmixclient.hpp
@@ -2,6 +2,7 @@
 
 #include "node.hpp"
 
+#include "api.h"
 #include "logging.hpp"
 #include "client.hpp"
 #include "connect.hpp"
@@ -22,10 +23,20 @@ class CMixClient {
 	std::vector<NodeDetails> network_details;
 	std::vector<Node> network_connections;
 
-	void initialized();
+	Api api;
+	KeyPair keypair;
+	std::vector<SharedKey> shared_keys;
+
+	void key_exchange(int i);
 
 	void initialize_connections();
 
+	cmix_proto::CMixMessage parse_cmix_message(std::vector<uint8_t> const& buffer);
+
+	void handle_key_exchange(int node_id, cmix_proto::KeyExchange const& ke);
+
+	void handle_message(int node_id, std::vector<uint8_t> const& message_buffer);
+
 public: 
 	CMixClient(std::vector<NodeDetails> details);
 	
diff --git a/client/main.cpp b/client/main.cpp
index fb05171..bcac249 100644
--- a/client/main.cpp
+++ b/client/main.cpp
@@ -14,7 +14,7 @@ int main(int argc, char* argv[]) {
 	
 	init_logging(boost::log::trivial::severity_level::trace, "client");
 	
-	BOOST_LOG_TRIVIAL(info) << "Started node";
+	BOOST_LOG_TRIVIAL(info) << "Started client";
 	
 	po::options_description desc("Allowed options");
 	desc.add_options()
diff --git a/client/node.cpp b/client/node.cpp
index 8fd1dd8..46375f4 100644
--- a/client/node.cpp
+++ b/client/node.cpp
@@ -13,6 +13,10 @@ void Node::async_connect(std::string next_host, std::string next_port, std::func
 	client.async_connect(next_host, next_port, on_connect);
 }
 
+void Node::receive(std::function<void (const std::vector<uint8_t>&)> receive_handler) {
+	client.receive(receive_handler);
+}
+
 void Node::close()
 {
 	client.close();
diff --git a/client/node.hpp b/client/node.hpp
index 3719223..afcf56a 100644
--- a/client/node.hpp
+++ b/client/node.hpp
@@ -22,6 +22,7 @@ inline void message_setter(cmix_proto::CMixMessage& m, cmix_proto::TYPE const& v
 
 MESSAGE_SETTER(ImAClient, imaclient)
 MESSAGE_SETTER(Bye, bye)
+MESSAGE_SETTER(KeyExchange, keyexchange)
 
 #undef MESSAGE_SETTER
 
@@ -50,6 +51,12 @@ public:
 	}
 	
 	/*!
+	 * \brief receive
+	 * \param receive_handler
+	 */
+	void receive(std::function<void(std::vector<uint8_t> const&)> receive_handler);
+	
+	/*!
 	 * \brief async_connect
 	 * \param next_host The host of the next node.
 	 * \param next_port The port of the next node.