OpenTTD
host.cpp
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1 /* $Id: host.cpp 26482 2014-04-23 20:13:33Z rubidium $ */
2 
3 /*
4  * This file is part of OpenTTD.
5  * OpenTTD 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, version 2.
6  * OpenTTD 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.
7  * See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with OpenTTD. If not, see <http://www.gnu.org/licenses/>.
8  */
9 
12 #ifdef ENABLE_NETWORK
13 
14 #include "../../stdafx.h"
15 #include "../../debug.h"
16 #include "address.h"
17 
18 #include "../../safeguards.h"
19 
26 
27 #if defined(PSP)
28 static void NetworkFindBroadcastIPsInternal(NetworkAddressList *broadcast) // PSP implementation
29 {
30 }
31 
32 #elif defined(BEOS_NET_SERVER) || defined(__HAIKU__) /* doesn't have neither getifaddrs or net/if.h */
33 /* Based on Andrew Bachmann's netstat+.c. Big thanks to him! */
34 extern "C" int _netstat(int fd, char **output, int verbose);
35 
36 int seek_past_header(char **pos, const char *header)
37 {
38  char *new_pos = strstr(*pos, header);
39  if (new_pos == 0) {
40  return B_ERROR;
41  }
42  *pos += strlen(header) + new_pos - *pos + 1;
43  return B_OK;
44 }
45 
46 static void NetworkFindBroadcastIPsInternal(NetworkAddressList *broadcast) // BEOS implementation
47 {
48  int sock = socket(AF_INET, SOCK_DGRAM, 0);
49 
50  if (sock < 0) {
51  DEBUG(net, 0, "[core] error creating socket");
52  return;
53  }
54 
55  char *output_pointer = NULL;
56  int output_length = _netstat(sock, &output_pointer, 1);
57  if (output_length < 0) {
58  DEBUG(net, 0, "[core] error running _netstat");
59  return;
60  }
61 
62  char **output = &output_pointer;
63  if (seek_past_header(output, "IP Interfaces:") == B_OK) {
64  for (;;) {
65  uint32 n;
66  int fields, read;
67  uint8 i1, i2, i3, i4, j1, j2, j3, j4;
68  uint32 ip;
69  uint32 netmask;
70 
71  fields = sscanf(*output, "%u: %hhu.%hhu.%hhu.%hhu, netmask %hhu.%hhu.%hhu.%hhu%n",
72  &n, &i1, &i2, &i3, &i4, &j1, &j2, &j3, &j4, &read);
73  read += 1;
74  if (fields != 9) {
75  break;
76  }
77 
78  ip = (uint32)i1 << 24 | (uint32)i2 << 16 | (uint32)i3 << 8 | (uint32)i4;
79  netmask = (uint32)j1 << 24 | (uint32)j2 << 16 | (uint32)j3 << 8 | (uint32)j4;
80 
81  if (ip != INADDR_LOOPBACK && ip != INADDR_ANY) {
82  sockaddr_storage address;
83  memset(&address, 0, sizeof(address));
84  ((sockaddr_in*)&address)->sin_addr.s_addr = htonl(ip | ~netmask);
85  NetworkAddress addr(address, sizeof(sockaddr));
86  if (!broadcast->Contains(addr)) *broadcast->Append() = addr;
87  }
88  if (read < 0) {
89  break;
90  }
91  *output += read;
92  }
93  closesocket(sock);
94  }
95 }
96 
97 #elif defined(HAVE_GETIFADDRS)
98 static void NetworkFindBroadcastIPsInternal(NetworkAddressList *broadcast) // GETIFADDRS implementation
99 {
100  struct ifaddrs *ifap, *ifa;
101 
102  if (getifaddrs(&ifap) != 0) return;
103 
104  for (ifa = ifap; ifa != NULL; ifa = ifa->ifa_next) {
105  if (!(ifa->ifa_flags & IFF_BROADCAST)) continue;
106  if (ifa->ifa_broadaddr == NULL) continue;
107  if (ifa->ifa_broadaddr->sa_family != AF_INET) continue;
108 
109  NetworkAddress addr(ifa->ifa_broadaddr, sizeof(sockaddr));
110  if (!broadcast->Contains(addr)) *broadcast->Append() = addr;
111  }
112  freeifaddrs(ifap);
113 }
114 
115 #elif defined(WIN32)
116 static void NetworkFindBroadcastIPsInternal(NetworkAddressList *broadcast) // Win32 implementation
117 {
118  SOCKET sock = socket(AF_INET, SOCK_DGRAM, 0);
119  if (sock == INVALID_SOCKET) return;
120 
121  DWORD len = 0;
122  int num = 2;
123  INTERFACE_INFO *ifo = CallocT<INTERFACE_INFO>(num);
124 
125  for (;;) {
126  if (WSAIoctl(sock, SIO_GET_INTERFACE_LIST, NULL, 0, ifo, num * sizeof(*ifo), &len, NULL, NULL) == 0) break;
127  free(ifo);
128  if (WSAGetLastError() != WSAEFAULT) {
129  closesocket(sock);
130  return;
131  }
132  num *= 2;
133  ifo = CallocT<INTERFACE_INFO>(num);
134  }
135 
136  for (uint j = 0; j < len / sizeof(*ifo); j++) {
137  if (ifo[j].iiFlags & IFF_LOOPBACK) continue;
138  if (!(ifo[j].iiFlags & IFF_BROADCAST)) continue;
139 
140  sockaddr_storage address;
141  memset(&address, 0, sizeof(address));
142  /* iiBroadcast is unusable, because it always seems to be set to 255.255.255.255. */
143  memcpy(&address, &ifo[j].iiAddress.Address, sizeof(sockaddr));
144  ((sockaddr_in*)&address)->sin_addr.s_addr = ifo[j].iiAddress.AddressIn.sin_addr.s_addr | ~ifo[j].iiNetmask.AddressIn.sin_addr.s_addr;
145  NetworkAddress addr(address, sizeof(sockaddr));
146  if (!broadcast->Contains(addr)) *broadcast->Append() = addr;
147  }
148 
149  free(ifo);
150  closesocket(sock);
151 }
152 
153 #else /* not HAVE_GETIFADDRS */
154 
155 #include "../../string_func.h"
156 
157 static void NetworkFindBroadcastIPsInternal(NetworkAddressList *broadcast) // !GETIFADDRS implementation
158 {
159  SOCKET sock = socket(AF_INET, SOCK_DGRAM, 0);
160  if (sock == INVALID_SOCKET) return;
161 
162  char buf[4 * 1024]; // Arbitrary buffer size
163  struct ifconf ifconf;
164 
165  ifconf.ifc_len = sizeof(buf);
166  ifconf.ifc_buf = buf;
167  if (ioctl(sock, SIOCGIFCONF, &ifconf) == -1) {
168  closesocket(sock);
169  return;
170  }
171 
172  const char *buf_end = buf + ifconf.ifc_len;
173  for (const char *p = buf; p < buf_end;) {
174  const struct ifreq *req = (const struct ifreq*)p;
175 
176  if (req->ifr_addr.sa_family == AF_INET) {
177  struct ifreq r;
178 
179  strecpy(r.ifr_name, req->ifr_name, lastof(r.ifr_name));
180  if (ioctl(sock, SIOCGIFFLAGS, &r) != -1 &&
181  (r.ifr_flags & IFF_BROADCAST) &&
182  ioctl(sock, SIOCGIFBRDADDR, &r) != -1) {
183  NetworkAddress addr(&r.ifr_broadaddr, sizeof(sockaddr));
184  if (!broadcast->Contains(addr)) *broadcast->Append() = addr;
185  }
186  }
187 
188  p += sizeof(struct ifreq);
189 #if defined(AF_LINK) && !defined(SUNOS)
190  p += req->ifr_addr.sa_len - sizeof(struct sockaddr);
191 #endif
192  }
193 
194  closesocket(sock);
195 }
196 #endif /* all NetworkFindBroadcastIPsInternals */
197 
204 {
206 
207  /* Now display to the debug all the detected ips */
208  DEBUG(net, 3, "Detected broadcast addresses:");
209  int i = 0;
210  for (NetworkAddress *addr = broadcast->Begin(); addr != broadcast->End(); addr++) {
211  addr->SetPort(NETWORK_DEFAULT_PORT);
212  DEBUG(net, 3, "%d) %s", i++, addr->GetHostname());
213  }
214 }
215 
216 #endif /* ENABLE_NETWORK */
Wrapper for (un)resolved network addresses; there&#39;s no reason to transform a numeric IP to a string a...
Definition: address.h:31
const T * Begin() const
Get the pointer to the first item (const)
void NetworkFindBroadcastIPs(NetworkAddressList *broadcast)
Find the IPv4 broadcast addresses; IPv6 uses a completely different strategy for broadcasting.
Definition: host.cpp:203
#define lastof(x)
Get the last element of an fixed size array.
Definition: depend.cpp:50
const T * End() const
Get the pointer behind the last valid item (const)
T * Append(uint to_add=1)
Append an item and return it.
bool Contains(const T &item) const
Tests whether a item is present in the vector.
Wrapper for network addresses.
#define DEBUG(name, level,...)
Output a line of debugging information.
Definition: debug.h:39
static const uint16 NETWORK_DEFAULT_PORT
The default port of the game server (TCP & UDP)
Definition: config.h:31
char * strecpy(char *dst, const char *src, const char *last)
Copies characters from one buffer to another.
Definition: depend.cpp:68
static void free(const void *ptr)
Version of the standard free that accepts const pointers.
Definition: depend.cpp:114
static void NetworkFindBroadcastIPsInternal(NetworkAddressList *broadcast)
Internal implementation for finding the broadcast IPs.
Definition: host.cpp:157