More robust get_address_info
[mono.git] / mono / utils / networking-posix.c
1 /*
2  * networking-posix.c: Modern posix networking code
3  *
4  * Author:
5  *      Rodrigo Kumpera (kumpera@gmail.com)
6  *
7  * (C) 2015 Xamarin
8  */
9
10 #include <mono/utils/networking.h>
11 #include <glib.h>
12
13 #ifdef HAVE_NETDB_H
14 #include <netdb.h>
15 #endif
16 #ifdef HAVE_SYS_IOCTL_H
17 #include <sys/ioctl.h>
18 #endif
19 #ifdef HAVE_NET_IF_H
20 #include <net/if.h>
21 #endif
22 #ifdef HAVE_UNISTD_H
23 #include <unistd.h>
24 #endif
25 #ifdef HAVE_GETIFADDRS
26 #include <ifaddrs.h>
27 #endif
28
29 static void*
30 get_address_from_sockaddr (struct sockaddr *sa)
31 {
32         switch (sa->sa_family) {
33         case AF_INET:
34                 return &((struct sockaddr_in*)sa)->sin_addr;
35         case AF_INET6:
36                 return &((struct sockaddr_in6*)sa)->sin6_addr;
37         }
38         return NULL;
39 }
40
41 #ifdef HAVE_GETADDRINFO
42
43 int
44 mono_get_address_info (const char *hostname, int port, int flags, MonoAddressInfo **result)
45 {
46         char service_name [16];
47         struct addrinfo hints, *res = NULL, *info;
48         MonoAddressEntry *cur = NULL, *prev = NULL;
49         MonoAddressInfo *addr_info;
50
51         memset (&hints, 0, sizeof (struct addrinfo));
52         *result = NULL;
53
54         hints.ai_family = PF_UNSPEC;
55         if (flags & MONO_HINT_IPV4)
56                 hints.ai_family = PF_INET;
57         else if (flags & MONO_HINT_IPV6)
58                 hints.ai_family = PF_INET6;
59
60         hints.ai_socktype = SOCK_STREAM;
61
62         if (flags & MONO_HINT_CANONICAL_NAME)
63                 hints.ai_flags = AI_CANONNAME;
64
65 /* Some ancient libc don't define AI_ADDRCONFIG */
66 #ifdef AI_ADDRCONFIG
67         if (flags & MONO_HINT_CONFIGURED_ONLY)
68                 hints.ai_flags = AI_ADDRCONFIG;
69 #endif
70         sprintf (service_name, "%d", port);
71     if (getaddrinfo (hostname, service_name, &hints, &info))
72                 return 1; /* FIXME propagate the error */
73
74         res = info;
75         *result = addr_info = g_new0 (MonoAddressInfo, 1);
76
77         while (res) {
78                 cur = g_new0 (MonoAddressEntry, 1);
79                 cur->family = res->ai_family;
80                 cur->socktype = res->ai_socktype;
81                 cur->protocol = res->ai_protocol;
82                 if (cur->family == PF_INET) {
83                         cur->address_len = sizeof (struct in_addr);
84                         cur->address.v4 = ((struct sockaddr_in*)res->ai_addr)->sin_addr;
85                 } else if (cur->family == PF_INET6) {
86                         cur->address_len = sizeof (struct in6_addr);
87                         cur->address.v6 = ((struct sockaddr_in6*)res->ai_addr)->sin6_addr;
88                 } else {
89                         g_warning ("Cannot handle address family %d", cur->family);
90                         res = res->ai_next;
91                         g_free (cur);
92                         continue;
93                 }
94
95                 if (res->ai_canonname)
96                         cur->canonical_name = g_strdup (res->ai_canonname);
97
98                 if (prev)
99                         prev->next = cur;
100                 else
101                         addr_info->entries = cur;
102                         
103                 prev = cur;
104                 res = res->ai_next;
105         }
106
107         freeaddrinfo (info);
108         return 0;
109 }
110
111 #endif
112
113 #ifdef HAVE_GETPROTOBYNAME
114
115 static int
116 fetch_protocol (const char *proto_name, int *cache, int *proto, int default_val)
117 {
118         if (!*cache) {
119                 struct protoent *pent;
120
121                 pent = getprotobyname (proto_name);
122                 *proto = pent ? pent->p_proto : default_val;
123                 *cache = 1;
124         }
125         return *proto;
126 }
127
128 int
129 mono_networking_get_tcp_protocol (void)
130 {
131         static int cache, proto;
132         return fetch_protocol ("tcp", &cache, &proto, 6); //6 is SOL_TCP on linux
133 }
134
135 int
136 mono_networking_get_ip_protocol (void)
137 {
138         static int cache, proto;
139         return fetch_protocol ("ip", &cache, &proto, 0); //0 is SOL_IP on linux
140 }
141
142 int
143 mono_networking_get_ipv6_protocol (void)
144 {
145         static int cache, proto;
146         return fetch_protocol ("ipv6", &cache, &proto, 41); //41 is SOL_IPV6 on linux
147 }
148
149 #endif
150
151 #if defined (HAVE_SIOCGIFCONF)
152
153 #define IFCONF_BUFF_SIZE 1024
154 #ifndef _SIZEOF_ADDR_IFREQ
155 #define _SIZEOF_ADDR_IFREQ(ifr) (sizeof (struct ifreq))
156 #endif
157
158 #define FOREACH_IFR(IFR, IFC) \
159         for (IFR = (IFC).ifc_req;       \
160         ifr < (struct ifreq*)((char*)(IFC).ifc_req + (IFC).ifc_len); \
161         ifr = (struct ifreq*)((char*)(IFR) + _SIZEOF_ADDR_IFREQ (*(IFR))))
162
163 void *
164 mono_get_local_interfaces (int family, int *interface_count)
165 {
166         int fd;
167         struct ifconf ifc;
168         struct ifreq *ifr;
169         int if_count = 0;
170         gboolean ignore_loopback = FALSE;
171         void *result = NULL;
172         char *result_ptr;
173
174         *interface_count = 0;
175
176         if (!mono_address_size_for_family (family))
177                 return NULL;
178
179         fd = socket (family, SOCK_STREAM, 0);
180         if (fd == -1)
181                 return NULL;
182
183         memset (&ifc, 0, sizeof (ifc));
184         ifc.ifc_len = IFCONF_BUFF_SIZE;
185         ifc.ifc_buf = g_malloc (IFCONF_BUFF_SIZE); /* We can't have such huge buffers on the stack. */
186         if (ioctl (fd, SIOCGIFCONF, &ifc) < 0)
187                 goto done;
188
189         FOREACH_IFR (ifr, ifc) {
190                 struct ifreq iflags;
191
192                 //only return addresses of the same type as @family
193                 if (ifr->ifr_addr.sa_family != family) {
194                         ifr->ifr_name [0] = '\0';
195                         continue;
196                 }
197
198                 strcpy (iflags.ifr_name, ifr->ifr_name);
199
200                 //ignore interfaces we can't get props for
201                 if (ioctl (fd, SIOCGIFFLAGS, &iflags) < 0) {
202                         ifr->ifr_name [0] = '\0';
203                         continue;
204                 }
205
206                 //ignore interfaces that are down
207                 if ((iflags.ifr_flags & IFF_UP) == 0) {
208                         ifr->ifr_name [0] = '\0';
209                         continue;
210                 }
211
212                 //If we have a non-loopback iface, don't return any loopback
213                 if ((iflags.ifr_flags & IFF_LOOPBACK) == 0) {
214                         ignore_loopback = TRUE;
215                         ifr->ifr_name [0] = 1;//1 means non-loopback
216                 } else {
217                         ifr->ifr_name [0] = 2; //2 means loopback
218                 }
219                 ++if_count;
220         }
221
222         result_ptr = result = g_malloc (if_count * mono_address_size_for_family (family));
223         FOREACH_IFR (ifr, ifc) {
224                 if (ifr->ifr_name [0] == '\0')
225                         continue;
226
227                 if (ignore_loopback && ifr->ifr_name [0] == 2) {
228                         --if_count;
229                         continue;
230                 }
231
232                 memcpy (result_ptr, get_address_from_sockaddr (&ifr->ifr_addr), mono_address_size_for_family (family));
233                 result_ptr += mono_address_size_for_family (family);
234         }
235         g_assert (result_ptr <= (char*)result + if_count * mono_address_size_for_family (family));
236
237 done:
238         *interface_count = if_count;
239         g_free (ifc.ifc_buf);
240         close (fd);
241         return result;
242 }
243
244 #elif defined(HAVE_GETIFADDRS)
245
246 void *
247 mono_get_local_interfaces (int family, int *interface_count)
248 {
249         struct ifaddrs *ifap = NULL, *cur;
250         int if_count = 0;
251         gboolean ignore_loopback = FALSE;
252         void *result;
253         char *result_ptr;
254
255         *interface_count = 0;
256
257         if (!mono_address_size_for_family (family))
258                 return NULL;
259
260         if (getifaddrs (&ifap))
261                 return NULL;
262
263         for (cur = ifap; cur; cur = cur->ifa_next) {
264                 //ignore interfaces with no address assigned
265                 if (!cur->ifa_addr)
266                         continue;
267
268                 //ignore interfaces that don't belong to @family
269                 if (cur->ifa_addr->sa_family != family)
270                         continue;
271
272                 //ignore interfaces that are down
273                 if ((cur->ifa_flags & IFF_UP) == 0)
274                         continue;
275
276                 //If we have a non-loopback iface, don't return any loopback
277                 if ((cur->ifa_flags & IFF_LOOPBACK) == 0)
278                         ignore_loopback = TRUE;
279
280                 if_count++;
281         }
282
283         result_ptr = result = g_malloc (if_count * mono_address_size_for_family (family));
284         for (cur = ifap; cur; cur = cur->ifa_next) {
285                 if (!cur->ifa_addr)
286                         continue;
287                 if (cur->ifa_addr->sa_family != family)
288                         continue;
289                 if ((cur->ifa_flags & IFF_UP) == 0)
290                         continue;
291
292                 //we decrement if_count because it did not on the previous loop.
293                 if (ignore_loopback && (cur->ifa_flags & IFF_LOOPBACK)) {
294                         --if_count;
295                         continue;
296                 }
297
298                 memcpy (result_ptr, get_address_from_sockaddr (cur->ifa_addr), mono_address_size_for_family (family));
299                 result_ptr += mono_address_size_for_family (family);
300         }
301         g_assert (result_ptr <= (char*)result + if_count * mono_address_size_for_family (family));
302
303         freeifaddrs (ifap);
304         *interface_count = if_count;
305         return result;
306 }
307
308 #endif
309
310 #ifdef HAVE_GETNAMEINFO
311
312 gboolean
313 mono_networking_addr_to_str (MonoAddress *address, char *buffer, socklen_t buflen)
314 {
315         MonoSocketAddress saddr;
316         socklen_t len;
317         mono_socket_address_init (&saddr, &len, address->family, &address->addr, 0);
318
319         return getnameinfo (&saddr.addr, len, buffer, buflen, NULL, 0, NI_NUMERICHOST) == 0;
320 }
321
322 #elif HAVE_INET_NTOP
323
324 gboolean
325 mono_networking_addr_to_str (MonoAddress *address, char *buffer, socklen_t buflen)
326 {
327         return inet_ntop (address->family, &address->addr, buffer, buflen) != NULL;
328 }
329
330 #endif
331
332 #ifndef _WIN32
333 // These are already defined in networking-windows.c for Windows
334 void
335 mono_networking_init (void)
336 {
337         //nothing really
338 }
339
340 void
341 mono_networking_shutdown (void)
342 {
343         //nothing really
344 }
345 #endif