Custom godot sockets for ENet now support DTLS.

Non-DTLS implementation uses plain NetSocket for performance as before.

2 files changed, 321 insertions, 56 deletions

diff --git a/thirdparty/enet/enet/enet.h b/thirdparty/enet/enet/enet.h
index 966e3a465d..ac7552adb2 100644
--- a/thirdparty/enet/enet/enet.h
+++ b/thirdparty/enet/enet/enet.h
@@ -578,6 +578,8 @@ ENET_API void       enet_host_channel_limit (ENetHost *, size_t);
 ENET_API void       enet_host_bandwidth_limit (ENetHost *, enet_uint32, enet_uint32);
 extern   void       enet_host_bandwidth_throttle (ENetHost *);
 extern  enet_uint32 enet_host_random_seed (void);
+ENET_API void enet_host_dtls_server_setup (ENetHost *, void *, void *);
+ENET_API void enet_host_dtls_client_setup (ENetHost *, void *, uint8_t, const char *);
 
 ENET_API int                 enet_peer_send (ENetPeer *, enet_uint8, ENetPacket *);
 ENET_API ENetPacket *        enet_peer_receive (ENetPeer *, enet_uint8 * channelID);
diff --git a/thirdparty/enet/godot.cpp b/thirdparty/enet/godot.cpp
index 63580b6d1a..da3a86277b 100644
--- a/thirdparty/enet/godot.cpp
+++ b/thirdparty/enet/godot.cpp
@@ -32,13 +32,313 @@
  @brief ENet Godot specific functions
 */
 
+#include "core/io/dtls_server.h"
 #include "core/io/ip.h"
 #include "core/io/net_socket.h"
+#include "core/io/packet_peer_dtls.h"
+#include "core/io/udp_server.h"
 #include "core/os/os.h"
 
 // This must be last for windows to compile (tested with MinGW)
 #include "enet/enet.h"
 
+/// Abstract ENet interface for UDP/DTLS.
+class ENetGodotSocket {
+
+public:
+	virtual Error bind(IP_Address p_ip, uint16_t p_port) = 0;
+	virtual Error sendto(const uint8_t *p_buffer, int p_len, int &r_sent, IP_Address p_ip, uint16_t p_port) = 0;
+	virtual Error recvfrom(uint8_t *p_buffer, int p_len, int &r_read, IP_Address &r_ip, uint16_t &r_port) = 0;
+	virtual int set_option(ENetSocketOption p_option, int p_value) = 0;
+	virtual void close() = 0;
+	virtual ~ENetGodotSocket(){};
+};
+
+class ENetDTLSClient;
+class ENetDTLSServer;
+
+/// NetSocket interface
+class ENetUDP : public ENetGodotSocket {
+
+	friend class ENetDTLSClient;
+	friend class ENetDTLSServer;
+
+private:
+	Ref<NetSocket> sock;
+	IP_Address address;
+	uint16_t port;
+	bool bound;
+
+public:
+	ENetUDP() {
+		sock = Ref<NetSocket>(NetSocket::create());
+		IP::Type ip_type = IP::TYPE_ANY;
+		bound = false;
+		sock->open(NetSocket::TYPE_UDP, ip_type);
+	}
+
+	~ENetUDP() {
+		sock->close();
+	}
+
+	Error bind(IP_Address p_ip, uint16_t p_port) {
+		address = p_ip;
+		port = p_port;
+		bound = true;
+		return sock->bind(address, port);
+	}
+
+	Error sendto(const uint8_t *p_buffer, int p_len, int &r_sent, IP_Address p_ip, uint16_t p_port) {
+		return sock->sendto(p_buffer, p_len, r_sent, p_ip, p_port);
+	}
+
+	Error recvfrom(uint8_t *p_buffer, int p_len, int &r_read, IP_Address &r_ip, uint16_t &r_port) {
+		Error err = sock->poll(NetSocket::POLL_TYPE_IN, 0);
+		if (err != OK)
+			return err;
+		return sock->recvfrom(p_buffer, p_len, r_read, r_ip, r_port);
+	}
+
+	int set_option(ENetSocketOption p_option, int p_value) {
+		switch (p_option) {
+			case ENET_SOCKOPT_NONBLOCK: {
+				sock->set_blocking_enabled(p_value ? false : true);
+				return 0;
+			} break;
+
+			case ENET_SOCKOPT_BROADCAST: {
+				sock->set_broadcasting_enabled(p_value ? true : false);
+				return 0;
+			} break;
+
+			case ENET_SOCKOPT_REUSEADDR: {
+				sock->set_reuse_address_enabled(p_value ? true : false);
+				return 0;
+			} break;
+
+			case ENET_SOCKOPT_RCVBUF: {
+				return -1;
+			} break;
+
+			case ENET_SOCKOPT_SNDBUF: {
+				return -1;
+			} break;
+
+			case ENET_SOCKOPT_RCVTIMEO: {
+				return -1;
+			} break;
+
+			case ENET_SOCKOPT_SNDTIMEO: {
+				return -1;
+			} break;
+
+			case ENET_SOCKOPT_NODELAY: {
+				sock->set_tcp_no_delay_enabled(p_value ? true : false);
+				return 0;
+			} break;
+		}
+
+		return -1;
+	}
+
+	void close() {
+		sock->close();
+	}
+};
+
+/// DTLS Client ENet interface
+class ENetDTLSClient : public ENetGodotSocket {
+
+	bool connected;
+	Ref<PacketPeerUDP> udp;
+	Ref<PacketPeerDTLS> dtls;
+	bool verify;
+	String for_hostname;
+	Ref<X509Certificate> cert;
+
+public:
+	ENetDTLSClient(ENetUDP *p_base, Ref<X509Certificate> p_cert, bool p_verify, String p_for_hostname) {
+		verify = p_verify;
+		for_hostname = p_for_hostname;
+		cert = p_cert;
+		udp.instance();
+		dtls = Ref<PacketPeerDTLS>(PacketPeerDTLS::create());
+		p_base->close();
+		if (p_base->bound) {
+			bind(p_base->address, p_base->port);
+		}
+		connected = false;
+	}
+
+	~ENetDTLSClient() {
+		close();
+	}
+
+	Error bind(IP_Address p_ip, uint16_t p_port) {
+		return udp->listen(p_port, p_ip);
+	}
+
+	Error sendto(const uint8_t *p_buffer, int p_len, int &r_sent, IP_Address p_ip, uint16_t p_port) {
+		if (!connected) {
+			udp->connect_to_host(p_ip, p_port);
+			dtls->connect_to_peer(udp, verify, for_hostname, cert);
+			connected = true;
+		}
+		dtls->poll();
+		if (dtls->get_status() == PacketPeerDTLS::STATUS_HANDSHAKING)
+			return ERR_BUSY;
+		else if (dtls->get_status() != PacketPeerDTLS::STATUS_CONNECTED)
+			return FAILED;
+		r_sent = p_len;
+		return dtls->put_packet(p_buffer, p_len);
+	}
+
+	Error recvfrom(uint8_t *p_buffer, int p_len, int &r_read, IP_Address &r_ip, uint16_t &r_port) {
+		dtls->poll();
+		if (dtls->get_status() == PacketPeerDTLS::STATUS_HANDSHAKING)
+			return ERR_BUSY;
+		if (dtls->get_status() != PacketPeerDTLS::STATUS_CONNECTED)
+			return FAILED;
+		int pc = dtls->get_available_packet_count();
+		if (pc == 0)
+			return ERR_BUSY;
+		else if (pc < 0)
+			return FAILED;
+
+		const uint8_t *buffer;
+		Error err = dtls->get_packet(&buffer, r_read);
+		ERR_FAIL_COND_V(err != OK, err);
+		ERR_FAIL_COND_V(p_len < r_read, ERR_OUT_OF_MEMORY);
+
+		copymem(p_buffer, buffer, r_read);
+		r_ip = udp->get_packet_address();
+		r_port = udp->get_packet_port();
+		return err;
+	}
+
+	int set_option(ENetSocketOption p_option, int p_value) {
+		return -1;
+	}
+
+	void close() {
+		dtls->disconnect_from_peer();
+		udp->close();
+	}
+};
+
+/// DTLSServer - ENet interface
+class ENetDTLSServer : public ENetGodotSocket {
+
+	Ref<DTLSServer> server;
+	Ref<UDPServer> udp_server;
+	Map<String, Ref<PacketPeerDTLS> > peers;
+	int last_service;
+
+public:
+	ENetDTLSServer(ENetUDP *p_base, Ref<CryptoKey> p_key, Ref<X509Certificate> p_cert) {
+		last_service = 0;
+		udp_server.instance();
+		p_base->close();
+		if (p_base->bound) {
+			bind(p_base->address, p_base->port);
+		}
+		server = Ref<DTLSServer>(DTLSServer::create());
+		server->setup(p_key, p_cert);
+	}
+
+	~ENetDTLSServer() {
+		close();
+	}
+
+	Error bind(IP_Address p_ip, uint16_t p_port) {
+		return udp_server->listen(p_port, p_ip);
+	}
+
+	Error sendto(const uint8_t *p_buffer, int p_len, int &r_sent, IP_Address p_ip, uint16_t p_port) {
+		String key = String(p_ip) + ":" + itos(p_port);
+		ERR_FAIL_COND_V(!peers.has(key), ERR_UNAVAILABLE);
+		Ref<PacketPeerDTLS> peer = peers[key];
+		Error err = peer->put_packet(p_buffer, p_len);
+		if (err == OK)
+			r_sent = p_len;
+		else if (err == ERR_BUSY)
+			r_sent = 0;
+		else
+			r_sent = -1;
+		return err;
+	}
+
+	Error recvfrom(uint8_t *p_buffer, int p_len, int &r_read, IP_Address &r_ip, uint16_t &r_port) {
+		// TODO limits? Maybe we can better enforce allowed connections!
+		if (udp_server->is_connection_available()) {
+			Ref<PacketPeerUDP> udp = udp_server->take_connection();
+			IP_Address peer_ip = udp->get_packet_address();
+			int peer_port = udp->get_packet_port();
+			Ref<PacketPeerDTLS> peer = server->take_connection(udp);
+			PacketPeerDTLS::Status status = peer->get_status();
+			if (status == PacketPeerDTLS::STATUS_HANDSHAKING || status == PacketPeerDTLS::STATUS_CONNECTED) {
+				String key = String(peer_ip) + ":" + itos(peer_port);
+				peers[key] = peer;
+			}
+		}
+
+		List<String> remove;
+		Error err = ERR_BUSY;
+		// TODO this needs to be fair!
+		for (Map<String, Ref<PacketPeerDTLS> >::Element *E = peers.front(); E; E = E->next()) {
+			Ref<PacketPeerDTLS> peer = E->get();
+			peer->poll();
+
+			if (peer->get_status() == PacketPeerDTLS::STATUS_HANDSHAKING)
+				continue;
+			else if (peer->get_status() != PacketPeerDTLS::STATUS_CONNECTED) {
+				// Peer disconnected, removing it.
+				remove.push_back(E->key());
+				continue;
+			}
+
+			if (peer->get_available_packet_count() > 0) {
+				const uint8_t *buffer;
+				err = peer->get_packet(&buffer, r_read);
+				if (err != OK || p_len < r_read) {
+					// Something wrong with this peer, removing it.
+					remove.push_back(E->key());
+					err = FAILED;
+					continue;
+				}
+
+				Vector<String> s = E->key().rsplit(":", false, 1);
+				ERR_CONTINUE(s.size() != 2); // BUG!
+
+				copymem(p_buffer, buffer, r_read);
+				r_ip = s[0];
+				r_port = s[1].to_int();
+				break; // err = OK
+			}
+		}
+
+		// Remove disconnected peers from map.
+		for (List<String>::Element *E = remove.front(); E; E = E->next()) {
+			peers.erase(E->get());
+		}
+
+		return err; // OK, ERR_BUSY, or possibly an error.
+	}
+
+	int set_option(ENetSocketOption p_option, int p_value) {
+		return -1;
+	}
+
+	void close() {
+		for (Map<String, Ref<PacketPeerDTLS> >::Element *E = peers.front(); E; E = E->next()) {
+			E->get()->disconnect_from_peer();
+		}
+		peers.clear();
+		udp_server->stop();
+		server->stop();
+	}
+};
+
 static enet_uint32 timeBase = 0;
 
 int enet_initialize(void) {
@@ -92,13 +392,23 @@ int enet_address_get_host(const ENetAddress *address, char *name, size_t nameLen
 
 ENetSocket enet_socket_create(ENetSocketType type) {
 
-	NetSocket *socket = NetSocket::create();
-	IP::Type ip_type = IP::TYPE_ANY;
-	socket->open(NetSocket::TYPE_UDP, ip_type);
+	ENetUDP *socket = memnew(ENetUDP);
 
 	return socket;
 }
 
+void enet_host_dtls_server_setup(ENetHost *host, void *p_key, void *p_cert) {
+	ENetUDP *sock = (ENetUDP *)host->socket;
+	host->socket = memnew(ENetDTLSServer(sock, Ref<CryptoKey>((CryptoKey *)p_key), Ref<X509Certificate>((X509Certificate *)p_cert)));
+	memdelete(sock);
+}
+
+void enet_host_dtls_client_setup(ENetHost *host, void *p_cert, uint8_t p_verify, const char *p_for_hostname) {
+	ENetUDP *sock = (ENetUDP *)host->socket;
+	host->socket = memnew(ENetDTLSClient(sock, Ref<X509Certificate>((X509Certificate *)p_cert), p_verify, String(p_for_hostname)));
+	memdelete(sock);
+}
+
 int enet_socket_bind(ENetSocket socket, const ENetAddress *address) {
 
 	IP_Address ip;
@@ -108,7 +418,7 @@ int enet_socket_bind(ENetSocket socket, const ENetAddress *address) {
 		ip.set_ipv6(address->host);
 	}
 
-	NetSocket *sock = (NetSocket *)socket;
+	ENetGodotSocket *sock = (ENetGodotSocket *)socket;
 	if (sock->bind(ip, address->port) != OK) {
 		return -1;
 	}
@@ -116,7 +426,7 @@ int enet_socket_bind(ENetSocket socket, const ENetAddress *address) {
 }
 
 void enet_socket_destroy(ENetSocket socket) {
-	NetSocket *sock = (NetSocket *)socket;
+	ENetGodotSocket *sock = (ENetGodotSocket *)socket;
 	sock->close();
 	memdelete(sock);
 }
@@ -125,7 +435,7 @@ int enet_socket_send(ENetSocket socket, const ENetAddress *address, const ENetBu
 
 	ERR_FAIL_COND_V(address == NULL, -1);
 
-	NetSocket *sock = (NetSocket *)socket;
+	ENetGodotSocket *sock = (ENetGodotSocket *)socket;
 	IP_Address dest;
 	Error err;
 	size_t i = 0;
@@ -167,15 +477,7 @@ int enet_socket_receive(ENetSocket socket, ENetAddress *address, ENetBuffer *buf
 
 	ERR_FAIL_COND_V(bufferCount != 1, -1);
 
-	NetSocket *sock = (NetSocket *)socket;
-
-	Error ret = sock->poll(NetSocket::POLL_TYPE_IN, 0);
-
-	if (ret == ERR_BUSY)
-		return 0;
-
-	if (ret != OK)
-		return -1;
+	ENetGodotSocket *sock = (ENetGodotSocket *)socket;
 
 	int read;
 	IP_Address ip;
@@ -215,47 +517,8 @@ int enet_socket_listen(ENetSocket socket, int backlog) {
 
 int enet_socket_set_option(ENetSocket socket, ENetSocketOption option, int value) {
 
-	NetSocket *sock = (NetSocket *)socket;
-
-	switch (option) {
-		case ENET_SOCKOPT_NONBLOCK: {
-			sock->set_blocking_enabled(value ? false : true);
-			return 0;
-		} break;
-
-		case ENET_SOCKOPT_BROADCAST: {
-			sock->set_broadcasting_enabled(value ? true : false);
-			return 0;
-		} break;
-
-		case ENET_SOCKOPT_REUSEADDR: {
-			sock->set_reuse_address_enabled(value ? true : false);
-			return 0;
-		} break;
-
-		case ENET_SOCKOPT_RCVBUF: {
-			return -1;
-		} break;
-
-		case ENET_SOCKOPT_SNDBUF: {
-			return -1;
-		} break;
-
-		case ENET_SOCKOPT_RCVTIMEO: {
-			return -1;
-		} break;
-
-		case ENET_SOCKOPT_SNDTIMEO: {
-			return -1;
-		} break;
-
-		case ENET_SOCKOPT_NODELAY: {
-			sock->set_tcp_no_delay_enabled(value ? true : false);
-			return 0;
-		} break;
-	}
-
-	return -1;
+	ENetGodotSocket *sock = (ENetGodotSocket *)socket;
+	return sock->set_option(option, value);
 }
 
 int enet_socket_get_option(ENetSocket socket, ENetSocketOption option, int *value) {