1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
|
/* $Id$ */
/**
* @file core/udp.cpp Basic functions to receive and send UDP packets.
*/
#ifdef ENABLE_NETWORK
#include "../../stdafx.h"
#include "../../debug.h"
#include "../../core/bitmath_func.hpp"
#include "../../core/math_func.hpp"
#include "../../core/alloc_func.hpp"
#include "../../date_func.h"
#include "packet.h"
#include "udp.h"
/**
* Start listening on the given host and port.
* @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 NetworkUDPSocketHandler::Listen(const uint32 host, const uint16 port, const bool broadcast)
{
struct sockaddr_in sin;
/* Make sure socket is closed */
this->Close();
this->sock = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
if (!this->IsConnected()) {
DEBUG(net, 0, "[udp] failed to start UDP listener");
return false;
}
SetNonBlocking(this->sock);
sin.sin_family = AF_INET;
/* Listen on all IPs */
sin.sin_addr.s_addr = host;
sin.sin_port = htons(port);
if (bind(this->sock, (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(this->sock, 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
*/
void NetworkUDPSocketHandler::Close()
{
if (!this->IsConnected()) return;
closesocket(this->sock);
this->sock = INVALID_SOCKET;
}
NetworkRecvStatus NetworkUDPSocketHandler::CloseConnection()
{
this->has_quit = true;
return NETWORK_RECV_STATUS_OKAY;
}
/**
* Send a packet over UDP
* @param p the packet to send
* @param recv the receiver (target) of the packet
*/
void NetworkUDPSocketHandler::SendPacket(Packet *p, NetworkAddress *recv)
{
int res;
p->PrepareToSend();
/* Send the buffer */
res = sendto(this->sock, (const char*)p->buffer, p->size, 0, (struct sockaddr *)recv->GetAddress(), recv->GetAddressLength());
/* 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
*/
void NetworkUDPSocketHandler::ReceivePackets()
{
struct sockaddr_storage client_addr;
memset(&client_addr, 0, sizeof(client_addr));
socklen_t client_len;
int nbytes;
Packet p(this);
int packet_len;
if (!this->IsConnected()) return;
packet_len = sizeof(p.buffer);
client_len = sizeof(client_addr);
/* Try to receive anything */
SetNonBlocking(this->sock); // Some OSes seem to lose the non-blocking status of the socket
nbytes = recvfrom(this->sock, (char*)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) {
NetworkAddress address(client_addr, client_len);
p.PrepareToRead();
/* 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", address.GetAddressAsString());
return;
}
/* Handle the packet */
this->HandleUDPPacket(&p, &address);
}
}
/**
* Serializes the NetworkGameInfo struct to the packet
* @param p the packet to write the data to
* @param info the NetworkGameInfo struct to serialize
*/
void NetworkUDPSocketHandler::Send_NetworkGameInfo(Packet *p, const NetworkGameInfo *info)
{
p->Send_uint8 (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++;
}
p->Send_uint8 (count); // Send number of GRFs
/* Send actual GRF Identifications */
for (c = info->grfconfig; c != NULL; c = c->next) {
if (!HasBit(c->flags, GCF_STATIC)) this->Send_GRFIdentifier(p, c);
}
}
/* NETWORK_GAME_INFO_VERSION = 3 */
p->Send_uint32(info->game_date);
p->Send_uint32(info->start_date);
/* NETWORK_GAME_INFO_VERSION = 2 */
p->Send_uint8 (info->companies_max);
p->Send_uint8 (info->companies_on);
p->Send_uint8 (info->spectators_max);
/* NETWORK_GAME_INFO_VERSION = 1 */
p->Send_string(info->server_name);
p->Send_string(info->server_revision);
p->Send_uint8 (info->server_lang);
p->Send_bool (info->use_password);
p->Send_uint8 (info->clients_max);
p->Send_uint8 (info->clients_on);
p->Send_uint8 (info->spectators_on);
p->Send_string(info->map_name);
p->Send_uint16(info->map_width);
p->Send_uint16(info->map_height);
p->Send_uint8 (info->map_set);
p->Send_bool (info->dedicated);
}
/**
* Deserializes the NetworkGameInfo struct from the packet
* @param p the packet to read the data from
* @param info the NetworkGameInfo to deserialize into
*/
void NetworkUDPSocketHandler::Recv_NetworkGameInfo(Packet *p, NetworkGameInfo *info)
{
static const Date MAX_DATE = ConvertYMDToDate(MAX_YEAR, 11, 31); // December is month 11
info->game_info_version = p->Recv_uint8();
/*
* 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 **dst = &info->grfconfig;
uint i;
uint num_grfs = p->Recv_uint8();
/* Broken/bad data. It cannot have that many NewGRFs. */
if (num_grfs > NETWORK_MAX_GRF_COUNT) return;
for (i = 0; i < num_grfs; i++) {
GRFConfig *c = CallocT<GRFConfig>(1);
this->Recv_GRFIdentifier(p, c);
this->HandleIncomingNetworkGameInfoGRFConfig(c);
/* Append GRFConfig to the list */
*dst = c;
dst = &c->next;
}
} // Fallthrough
case 3:
info->game_date = Clamp(p->Recv_uint32(), 0, MAX_DATE);
info->start_date = Clamp(p->Recv_uint32(), 0, MAX_DATE);
/* Fallthrough */
case 2:
info->companies_max = p->Recv_uint8 ();
info->companies_on = p->Recv_uint8 ();
info->spectators_max = p->Recv_uint8 ();
/* Fallthrough */
case 1:
p->Recv_string(info->server_name, sizeof(info->server_name));
p->Recv_string(info->server_revision, sizeof(info->server_revision));
info->server_lang = p->Recv_uint8 ();
info->use_password = p->Recv_bool ();
info->clients_max = p->Recv_uint8 ();
info->clients_on = p->Recv_uint8 ();
info->spectators_on = p->Recv_uint8 ();
if (info->game_info_version < 3) { // 16 bits dates got scrapped and are read earlier
info->game_date = p->Recv_uint16() + DAYS_TILL_ORIGINAL_BASE_YEAR;
info->start_date = p->Recv_uint16() + DAYS_TILL_ORIGINAL_BASE_YEAR;
}
p->Recv_string(info->map_name, sizeof(info->map_name));
info->map_width = p->Recv_uint16();
info->map_height = p->Recv_uint16();
info->map_set = p->Recv_uint8 ();
info->dedicated = p->Recv_bool ();
if (info->server_lang >= NETWORK_NUM_LANGUAGES) info->server_lang = 0;
if (info->map_set >= NETWORK_NUM_LANDSCAPES) info->map_set = 0;
}
}
/**
* Defines a simple (switch) case for each network packet
* @param type the packet type to create the case for
*/
#define UDP_COMMAND(type) case type: this->NetworkPacketReceive_ ## type ## _command(p, client_addr); break;
/**
* Handle an incoming packets by sending it to the correct function.
* @param p the received packet
* @param client_addr the sender of the packet
*/
void NetworkUDPSocketHandler::HandleUDPPacket(Packet *p, NetworkAddress *client_addr)
{
PacketUDPType type;
/* New packet == new client, which has not quit yet */
this->has_quit = false;
type = (PacketUDPType)p->Recv_uint8();
switch (this->HasClientQuit() ? PACKET_UDP_END : type) {
UDP_COMMAND(PACKET_UDP_CLIENT_FIND_SERVER);
UDP_COMMAND(PACKET_UDP_SERVER_RESPONSE);
UDP_COMMAND(PACKET_UDP_CLIENT_DETAIL_INFO);
UDP_COMMAND(PACKET_UDP_SERVER_DETAIL_INFO);
UDP_COMMAND(PACKET_UDP_SERVER_REGISTER);
UDP_COMMAND(PACKET_UDP_MASTER_ACK_REGISTER);
UDP_COMMAND(PACKET_UDP_CLIENT_GET_LIST);
UDP_COMMAND(PACKET_UDP_MASTER_RESPONSE_LIST);
UDP_COMMAND(PACKET_UDP_SERVER_UNREGISTER);
UDP_COMMAND(PACKET_UDP_CLIENT_GET_NEWGRFS);
UDP_COMMAND(PACKET_UDP_SERVER_NEWGRFS);
default:
if (this->HasClientQuit()) {
DEBUG(net, 0, "[udp] received invalid packet type %d from %s", type, client_addr->GetAddressAsString());
} else {
DEBUG(net, 0, "[udp] received illegal packet from %s", client_addr->GetAddressAsString());
}
break;
}
}
/**
* Create stub implementations for all receive commands that only
* show a warning that the given command is not available for the
* socket where the packet came from.
* @param type the packet type to create the stub for
*/
#define DEFINE_UNAVAILABLE_UDP_RECEIVE_COMMAND(type) \
void NetworkUDPSocketHandler::NetworkPacketReceive_## type ##_command(\
Packet *p, NetworkAddress *client_addr) { \
DEBUG(net, 0, "[udp] received packet type %d on wrong port from %s", \
type, client_addr->GetAddressAsString()); \
}
DEFINE_UNAVAILABLE_UDP_RECEIVE_COMMAND(PACKET_UDP_CLIENT_FIND_SERVER);
DEFINE_UNAVAILABLE_UDP_RECEIVE_COMMAND(PACKET_UDP_SERVER_RESPONSE);
DEFINE_UNAVAILABLE_UDP_RECEIVE_COMMAND(PACKET_UDP_CLIENT_DETAIL_INFO);
DEFINE_UNAVAILABLE_UDP_RECEIVE_COMMAND(PACKET_UDP_SERVER_DETAIL_INFO);
DEFINE_UNAVAILABLE_UDP_RECEIVE_COMMAND(PACKET_UDP_SERVER_REGISTER);
DEFINE_UNAVAILABLE_UDP_RECEIVE_COMMAND(PACKET_UDP_MASTER_ACK_REGISTER);
DEFINE_UNAVAILABLE_UDP_RECEIVE_COMMAND(PACKET_UDP_CLIENT_GET_LIST);
DEFINE_UNAVAILABLE_UDP_RECEIVE_COMMAND(PACKET_UDP_MASTER_RESPONSE_LIST);
DEFINE_UNAVAILABLE_UDP_RECEIVE_COMMAND(PACKET_UDP_SERVER_UNREGISTER);
DEFINE_UNAVAILABLE_UDP_RECEIVE_COMMAND(PACKET_UDP_CLIENT_GET_NEWGRFS);
DEFINE_UNAVAILABLE_UDP_RECEIVE_COMMAND(PACKET_UDP_SERVER_NEWGRFS);
#endif /* ENABLE_NETWORK */
|