1 files changed, 297 insertions, 0 deletions
diff --git a/src/network/core/udp.cpp b/src/network/core/udp.cpp
new file mode 100644
index 000000000..6699b4b87
--- /dev/null
+++ b/src/network/core/udp.cpp
@@ -0,0 +1,297 @@
+/* $Id$ */
+
+#ifdef ENABLE_NETWORK
+
+#include "../../stdafx.h"
+#include "../../debug.h"
+#include "../../macros.h"
+#include "packet.h"
+#include "udp.h"
+
+/**
+ * @file udp.c Basic functions to receive and send UDP packets.
+ */
+
+/**
+ * Start listening on the given host and port.
+ * @param udp       the place where the (references to the) UDP are stored
+ * @param host      the host (ip) to listen on
+ * @param port      the port to listen on
+ * @param broadcast whether to allow broadcast sending/receiving
+ * @return true if the listening succeeded
+ */
+bool NetworkUDPListen(SOCKET *udp, const uint32 host, const uint16 port, const bool broadcast)
+{
+	struct sockaddr_in sin;
+
+	/* Make sure socket is closed */
+	NetworkUDPClose(udp);
+
+	*udp = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
+	if (*udp == INVALID_SOCKET) {
+		DEBUG(net, 0, "[udp] failed to start UDP listener");
+		return false;
+	}
+
+	/* set nonblocking mode for socket */
+	{
+		unsigned long blocking = 1;
+#ifndef BEOS_NET_SERVER
+		ioctlsocket(*udp, FIONBIO, &blocking);
+#else
+		setsockopt(*udp, SOL_SOCKET, SO_NONBLOCK, &blocking, NULL);
+#endif
+	}
+
+	sin.sin_family = AF_INET;
+	/* Listen on all IPs */
+	sin.sin_addr.s_addr = host;
+	sin.sin_port = htons(port);
+
+	if (bind(*udp, (struct sockaddr*)&sin, sizeof(sin)) != 0) {
+		DEBUG(net, 0, "[udp] bind failed on %s:%i", inet_ntoa(*(struct in_addr *)&host), port);
+		return false;
+	}
+
+	if (broadcast) {
+		/* Enable broadcast */
+		unsigned long val = 1;
+#ifndef BEOS_NET_SERVER // will work around this, some day; maybe.
+		setsockopt(*udp, SOL_SOCKET, SO_BROADCAST, (char *) &val , sizeof(val));
+#endif
+	}
+
+	DEBUG(net, 1, "[udp] listening on port %s:%d", inet_ntoa(*(struct in_addr *)&host), port);
+
+	return true;
+}
+
+/**
+ * Close the given UDP socket
+ * @param udp the socket to close
+ */
+void NetworkUDPClose(SOCKET *udp)
+{
+	if (*udp == INVALID_SOCKET) return;
+
+	closesocket(*udp);
+	*udp = INVALID_SOCKET;
+}
+
+
+/**
+ * Send a packet over UDP
+ * @param udp  the socket to send over
+ * @param p    the packet to send
+ * @param recv the receiver (target) of the packet
+ */
+void NetworkSendUDP_Packet(const SOCKET udp, Packet *p, const struct sockaddr_in *recv)
+{
+	int res;
+
+	NetworkSend_FillPacketSize(p);
+
+	/* Send the buffer */
+	res = sendto(udp, p->buffer, p->size, 0, (struct sockaddr *)recv, sizeof(*recv));
+
+	/* Check for any errors, but ignore it otherwise */
+	if (res == -1) DEBUG(net, 1, "[udp] sendto failed with: %i", GET_LAST_ERROR());
+}
+
+/**
+ * Receive a packet at UDP level
+ * @param udp the socket to receive the packet on
+ */
+void NetworkUDPReceive(const SOCKET udp)
+{
+	struct sockaddr_in client_addr;
+	socklen_t client_len;
+	int nbytes;
+	Packet p;
+	int packet_len;
+
+	packet_len = sizeof(p.buffer);
+	client_len = sizeof(client_addr);
+
+	/* Try to receive anything */
+	nbytes = recvfrom(udp, p.buffer, packet_len, 0, (struct sockaddr *)&client_addr, &client_len);
+
+	/* We got some bytes for the base header of the packet. */
+	if (nbytes > 2) {
+		NetworkRecv_ReadPacketSize(&p);
+
+		/* If the size does not match the packet must be corrupted.
+		 * Otherwise it will be marked as corrupted later on. */
+		if (nbytes != p.size) {
+			DEBUG(net, 1, "received a packet with mismatching size from %s:%d",
+					inet_ntoa(client_addr.sin_addr), ntohs(client_addr.sin_port));
+
+			return;
+		}
+
+		/* Put the position on the right place */
+		p.pos = 2;
+		p.next = NULL;
+
+		/* Handle the packet */
+		NetworkHandleUDPPacket(udp, &p, &client_addr);
+	}
+}
+
+
+/**
+ * Serializes the GRFIdentifier (GRF ID and MD5 checksum) to the packet
+ * @param p the packet to write the data to
+ * @param c the configuration to write the GRF ID and MD5 checksum from
+ */
+void NetworkSend_GRFIdentifier(Packet *p, const GRFConfig *c)
+{
+	uint j;
+	NetworkSend_uint32(p, c->grfid);
+	for (j = 0; j < sizeof(c->md5sum); j++) {
+		NetworkSend_uint8 (p, c->md5sum[j]);
+	}
+}
+
+/**
+ * Deserializes the GRFIdentifier (GRF ID and MD5 checksum) from the packet
+ * @param cs the client state (for closing connect on out-of-bounds reading etc)
+ * @param p  the packet to read the data from
+ * @param c  the configuration to write the GRF ID and MD5 checksum to
+ */
+void NetworkRecv_GRFIdentifier(NetworkClientState *cs, Packet *p, GRFConfig *c)
+{
+	uint j;
+	c->grfid = NetworkRecv_uint32(cs, p);
+	for (j = 0; j < sizeof(c->md5sum); j++) {
+		c->md5sum[j] = NetworkRecv_uint8(cs, p);
+	}
+}
+
+
+/**
+ * Serializes the NetworkGameInfo struct to the packet
+ * @param p    the packet to write the data to
+ * @param info the NetworkGameInfo struct to serialize
+ */
+void NetworkSend_NetworkGameInfo(Packet *p, const NetworkGameInfo *info)
+{
+	NetworkSend_uint8 (p, NETWORK_GAME_INFO_VERSION);
+
+	/*
+	 *              Please observe the order.
+	 * The parts must be read in the same order as they are sent!
+	 */
+
+	/* Update the documentation in udp.h on changes
+	 * to the NetworkGameInfo wire-protocol! */
+
+	/* NETWORK_GAME_INFO_VERSION = 4 */
+	{
+		/* Only send the GRF Identification (GRF_ID and MD5 checksum) of
+		 * the GRFs that are needed, i.e. the ones that the server has
+		 * selected in the NewGRF GUI and not the ones that are used due
+		 * to the fact that they are in [newgrf-static] in openttd.cfg */
+		const GRFConfig *c;
+		uint count = 0;
+
+		/* Count number of GRFs to send information about */
+		for (c = info->grfconfig; c != NULL; c = c->next) {
+			if (!HASBIT(c->flags, GCF_STATIC)) count++;
+		}
+		NetworkSend_uint8 (p, count); // Send number of GRFs
+
+		/* Send actual GRF Identifications */
+		for (c = info->grfconfig; c != NULL; c = c->next) {
+			if (!HASBIT(c->flags, GCF_STATIC)) NetworkSend_GRFIdentifier(p, c);
+		}
+	}
+
+	/* NETWORK_GAME_INFO_VERSION = 3 */
+	NetworkSend_uint32(p, info->game_date);
+	NetworkSend_uint32(p, info->start_date);
+
+	/* NETWORK_GAME_INFO_VERSION = 2 */
+	NetworkSend_uint8 (p, info->companies_max);
+	NetworkSend_uint8 (p, info->companies_on);
+	NetworkSend_uint8 (p, info->spectators_max);
+
+	/* NETWORK_GAME_INFO_VERSION = 1 */
+	NetworkSend_string(p, info->server_name);
+	NetworkSend_string(p, info->server_revision);
+	NetworkSend_uint8 (p, info->server_lang);
+	NetworkSend_uint8 (p, info->use_password);
+	NetworkSend_uint8 (p, info->clients_max);
+	NetworkSend_uint8 (p, info->clients_on);
+	NetworkSend_uint8 (p, info->spectators_on);
+	NetworkSend_string(p, info->map_name);
+	NetworkSend_uint16(p, info->map_width);
+	NetworkSend_uint16(p, info->map_height);
+	NetworkSend_uint8 (p, info->map_set);
+	NetworkSend_uint8 (p, info->dedicated);
+}
+
+/**
+ * Deserializes the NetworkGameInfo struct from the packet
+ * @param cs   the client state (for closing connect on out-of-bounds reading etc)
+ * @param p    the packet to read the data from
+ * @param info the NetworkGameInfo to deserialize into
+ */
+void NetworkRecv_NetworkGameInfo(NetworkClientState *cs, Packet *p, NetworkGameInfo *info)
+{
+	info->game_info_version = NetworkRecv_uint8(cs, p);
+
+	/*
+	 *              Please observe the order.
+	 * The parts must be read in the same order as they are sent!
+	 */
+
+	/* Update the documentation in udp.h on changes
+	 * to the NetworkGameInfo wire-protocol! */
+
+	switch (info->game_info_version) {
+		case 4: {
+			GRFConfig *c, **dst = &info->grfconfig;
+			uint i;
+			uint num_grfs = NetworkRecv_uint8(cs, p);
+
+			for (i = 0; i < num_grfs; i++) {
+				c = calloc(1, sizeof(*c));
+				NetworkRecv_GRFIdentifier(cs, p, c);
+				HandleIncomingNetworkGameInfoGRFConfig(c);
+
+				/* Append GRFConfig to the list */
+				*dst = c;
+				dst = &c->next;
+			}
+		} /* Fallthrough */
+		case 3:
+			info->game_date      = NetworkRecv_uint32(cs, p);
+			info->start_date     = NetworkRecv_uint32(cs, p);
+			/* Fallthrough */
+		case 2:
+			info->companies_max  = NetworkRecv_uint8 (cs, p);
+			info->companies_on   = NetworkRecv_uint8 (cs, p);
+			info->spectators_max = NetworkRecv_uint8 (cs, p);
+			/* Fallthrough */
+		case 1:
+			NetworkRecv_string(cs, p, info->server_name,     sizeof(info->server_name));
+			NetworkRecv_string(cs, p, info->server_revision, sizeof(info->server_revision));
+			info->server_lang    = NetworkRecv_uint8 (cs, p);
+			info->use_password   = NetworkRecv_uint8 (cs, p);
+			info->clients_max    = NetworkRecv_uint8 (cs, p);
+			info->clients_on     = NetworkRecv_uint8 (cs, p);
+			info->spectators_on  = NetworkRecv_uint8 (cs, p);
+			if (info->game_info_version < 3) { // 16 bits dates got scrapped and are read earlier
+				info->game_date    = NetworkRecv_uint16(cs, p) + DAYS_TILL_ORIGINAL_BASE_YEAR;
+				info->start_date   = NetworkRecv_uint16(cs, p) + DAYS_TILL_ORIGINAL_BASE_YEAR;
+			}
+			NetworkRecv_string(cs, p, info->map_name, sizeof(info->map_name));
+			info->map_width      = NetworkRecv_uint16(cs, p);
+			info->map_height     = NetworkRecv_uint16(cs, p);
+			info->map_set        = NetworkRecv_uint8 (cs, p);
+			info->dedicated      = NetworkRecv_uint8 (cs, p);
+	}
+}
+
+#endif /* ENABLE_NETWORK */