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
|
/* network.h
*
* Functions for the core networking.
*
* Copyright (C) 2013 Tox project All Rights Reserved.
*
* This file is part of Tox.
*
* Tox 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.
*
* Tox 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 Tox. If not, see <http://www.gnu.org/licenses/>.
*
*/
#include "network.h"
/* return current UNIX time in microseconds (us). */
uint64_t current_time(void)
{
uint64_t time;
#ifdef WIN32
/* This probably works fine */
FILETIME ft;
GetSystemTimeAsFileTime(&ft);
time = ft.dwHighDateTime;
time <<= 32;
time |= ft.dwLowDateTime;
time -= 116444736000000000UL;
return time / 10;
#else
struct timeval a;
gettimeofday(&a, NULL);
time = 1000000UL * a.tv_sec + a.tv_usec;
return time;
#endif
}
/* return a random number.
* NOTE: This function should probably not be used where cryptographic randomness is absolutely necessary.
*/
uint32_t random_int(void)
{
#ifndef VANILLA_NACL
/* NOTE: this function comes from libsodium. */
return randombytes_random();
#else
return random();
#endif
}
/* Basic network functions:
* Function to send packet(data) of length length to ip_port.
*/
int sendpacket(int sock, IP_Port ip_port, uint8_t *data, uint32_t length)
{
ADDR addr = {AF_INET, ip_port.port, ip_port.ip};
return sendto(sock, (char *) data, length, 0, (struct sockaddr *)&addr, sizeof(addr));
}
/* Function to receive data
* ip and port of sender is put into ip_port.
* Packet data is put into data.
* Packet length is put into length.
* Dump all empty packets.
*/
static int receivepacket(int sock, IP_Port *ip_port, uint8_t *data, uint32_t *length)
{
ADDR addr;
#ifdef WIN32
int addrlen = sizeof(addr);
#else
uint32_t addrlen = sizeof(addr);
#endif
(*(int32_t *)length) = recvfrom(sock, (char *) data, MAX_UDP_PACKET_SIZE, 0, (struct sockaddr *)&addr, &addrlen);
if (*(int32_t *)length <= 0)
return -1; /* Nothing received or empty packet. */
ip_port->ip = addr.ip;
ip_port->port = addr.port;
return 0;
}
void networking_registerhandler(Networking_Core *net, uint8_t byte, packet_handler_callback cb, void *object)
{
net->packethandlers[byte].function = cb;
net->packethandlers[byte].object = object;
}
void networking_poll(Networking_Core *net)
{
IP_Port ip_port;
uint8_t data[MAX_UDP_PACKET_SIZE];
uint32_t length;
while (receivepacket(net->sock, &ip_port, data, &length) != -1) {
if (length < 1) continue;
if (!(net->packethandlers[data[0]].function)) continue;
net->packethandlers[data[0]].function(net->packethandlers[data[0]].object, ip_port, data, length);
}
}
uint8_t at_startup_ran;
static int at_startup(void)
{
if (at_startup_ran != 0)
return 0;
#ifdef WIN32
WSADATA wsaData;
if (WSAStartup(MAKEWORD(2, 2), &wsaData) != NO_ERROR)
return -1;
#else
srandom((uint32_t)current_time());
#endif
srand((uint32_t)current_time());
at_startup_ran = 1;
return 0;
}
/* TODO: Put this somewhere
static void at_shutdown(void)
{
#ifdef WIN32
WSACleanup();
#endif
}
*/
/* Initialize networking.
* Bind to ip and port.
* ip must be in network order EX: 127.0.0.1 = (7F000001).
* port is in host byte order (this means don't worry about it).
*
* returns Networking_Core object if no problems
* returns NULL if there are problems.
*/
Networking_Core *new_networking(IP ip, uint16_t port)
{
if (at_startup() != 0)
return NULL;
/* Initialize our socket. */
Networking_Core *temp = calloc(1, sizeof(Networking_Core));
if (temp == NULL)
return NULL;
temp->sock = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
/* Check for socket error. */
#ifdef WIN32
if (temp->sock == INVALID_SOCKET) { /* MSDN recommends this. */
free(temp);
return NULL;
}
#else
if (temp->sock < 0) {
free(temp);
return NULL;
}
#endif
/* Functions to increase the size of the send and receive UDP buffers.
* NOTE: Uncomment if necessary.
*/
/*
int n = 1024 * 1024 * 2;
if(setsockopt(sock, SOL_SOCKET, SO_RCVBUF, (char*)&n, sizeof(n)) == -1)
{
return -1;
}
if(setsockopt(sock, SOL_SOCKET, SO_SNDBUF, (char*)&n, sizeof(n)) == -1)
return -1;
*/
/* Enable broadcast on socket. */
int broadcast = 1;
setsockopt(temp->sock, SOL_SOCKET, SO_BROADCAST, (char *)&broadcast, sizeof(broadcast));
/* Set socket nonblocking. */
#ifdef WIN32
/* I think this works for Windows. */
u_long mode = 1;
/* ioctl(sock, FIONBIO, &mode); */
ioctlsocket(temp->sock, FIONBIO, &mode);
#else
fcntl(temp->sock, F_SETFL, O_NONBLOCK, 1);
#endif
/* Bind our socket to port PORT and address 0.0.0.0 */
ADDR addr = {AF_INET, htons(port), ip};
bind(temp->sock, (struct sockaddr *)&addr, sizeof(addr));
return temp;
}
/* Function to cleanup networking stuff. */
void kill_networking(Networking_Core *net)
{
#ifdef WIN32
closesocket(net->sock);
#else
close(net->sock);
#endif
free(net);
return;
}
|
