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
|
/* 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"
/* returns current UNIX time in microseconds (us). */
uint64_t current_time()
{
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()
{
#ifndef VANILLA_NACL
//NOTE: this function comes from libsodium
return randombytes_random();
#else
return random();
#endif
}
/* our UDP socket, a global variable. */
static int sock;
/* Basic network functions:
Function to send packet(data) of length length to ip_port */
int sendpacket(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
the packet data into data
the packet length into length.
dump all empty packets. */
int receivepacket(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;
}
/* 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 0 if no problems
returns -1 if there are problems */
int init_networking(IP ip, uint16_t port)
{
#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());
/* initialize our socket */
sock = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
/* Check for socket error */
#ifdef WIN32
if (sock == INVALID_SOCKET) /* MSDN recommends this */
return -1;
#else
if (sock < 0)
return -1;
#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(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(sock, FIONBIO, &mode);
#else
fcntl(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(sock, (struct sockaddr*)&addr, sizeof(addr));
return 0;
}
/* function to cleanup networking stuff */
void shutdown_networking()
{
#ifdef WIN32
closesocket(sock);
WSACleanup();
#else
close(sock);
#endif
return;
}
/* resolves provided address to a binary data in network byte order
address is ASCII null terminated string
address should represent IPv4, IPv6 or a hostname
on success returns a data in network byte order that can be used to set IP.i or IP_Port.ip.i
on failure returns -1 */
int resolve_addr(const char *address)
{
struct addrinfo hints;
memset(&hints, 0, sizeof(hints));
hints.ai_family = AF_UNSPEC; //support both IPv4 and IPv6
hints.ai_socktype = SOCK_DGRAM; //type of socket Tox uses
struct addrinfo *server = NULL;
int success = getaddrinfo(address, "echo", &hints, &server);
if(success != 0)
return -1;
int resolved = ((struct sockaddr_in*)server->ai_addr)->sin_addr.s_addr;
freeaddrinfo(server);
return resolved;
}
|
