1 /* $NetBSD: util.c,v 1.2 2011/06/11 18:03:17 christos Exp $ */
2
3 /*-
4 * Copyright (c) 2000 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Frank van der Linden.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29 * POSSIBILITY OF SUCH DAMAGE.
30 */
31
32 #include <sys/types.h>
33 #include <sys/socket.h>
34 #include <sys/queue.h>
35 #include <net/if.h>
36 #include <netinet/in.h>
37 #include <assert.h>
38 #include <ifaddrs.h>
39 #include <poll.h>
40 #include <rpc/rpc.h>
41 #include <errno.h>
42 #include <stdlib.h>
43 #include <string.h>
44 #include <unistd.h>
45 #include <netdb.h>
46 #include <netconfig.h>
47 #include <stdio.h>
48 #include <arpa/inet.h>
49
50 #include <rump/rump.h>
51 #include <rump/rump_syscalls.h>
52
53 #include "rpcbind.h"
54
55 static struct sockaddr_in *local_in4;
56 #ifdef INET6
57 static struct sockaddr_in6 *local_in6;
58 #endif
59
60 static int bitmaskcmp(void *, void *, void *, int);
61 #ifdef INET6
62 static void in6_fillscopeid(struct sockaddr_in6 *);
63 #endif
64
65 /*
66 * For all bits set in "mask", compare the corresponding bits in
67 * "dst" and "src", and see if they match.
68 */
69 static int
bitmaskcmp(void * dst,void * src,void * mask,int bytelen)70 bitmaskcmp(void *dst, void *src, void *mask, int bytelen)
71 {
72 int i, j;
73 u_int8_t *p1 = dst, *p2 = src, *netmask = mask;
74 u_int8_t bitmask;
75
76 for (i = 0; i < bytelen; i++) {
77 for (j = 0; j < 8; j++) {
78 bitmask = 1 << j;
79 if (!(netmask[i] & bitmask))
80 continue;
81 if ((p1[i] & bitmask) != (p2[i] & bitmask))
82 return 1;
83 }
84 }
85
86 return 0;
87 }
88
89 /*
90 * Taken from ifconfig.c
91 */
92 #ifdef INET6
93 static void
in6_fillscopeid(struct sockaddr_in6 * sin6)94 in6_fillscopeid(struct sockaddr_in6 *sin6)
95 {
96 if (IN6_IS_ADDR_LINKLOCAL(&sin6->sin6_addr)) {
97 sin6->sin6_scope_id =
98 ntohs(*(u_int16_t *)&sin6->sin6_addr.s6_addr[2]);
99 sin6->sin6_addr.s6_addr[2] = sin6->sin6_addr.s6_addr[3] = 0;
100 }
101 }
102 #endif
103
104 char *
addrmerge(struct netbuf * caller,char * serv_uaddr,char * clnt_uaddr,char * netid)105 addrmerge(struct netbuf *caller, char *serv_uaddr, char *clnt_uaddr,
106 char *netid)
107 {
108 struct ifaddrs *ifap, *ifp, *bestif;
109 #ifdef INET6
110 struct sockaddr_in6 *servsin6, *sin6mask, *clntsin6, *ifsin6, *realsin6;
111 struct sockaddr_in6 *newsin6;
112 #endif
113 struct sockaddr_in *servsin, *sinmask, *clntsin, *newsin, *ifsin;
114 struct netbuf *serv_nbp, *clnt_nbp = NULL, tbuf;
115 struct sockaddr *serv_sa;
116 struct sockaddr *clnt_sa;
117 struct sockaddr_storage ss;
118 struct netconfig *nconf;
119 struct sockaddr *clnt = caller->buf;
120 char *ret = NULL;
121
122 #ifdef INET6
123 servsin6 = ifsin6 = newsin6 = NULL; /* XXXGCC -Wuninitialized */
124 #endif
125 servsin = newsin = NULL; /* XXXGCC -Wuninitialized */
126
127 #ifdef RPCBIND_DEBUG
128 if (debugging)
129 fprintf(stderr, "addrmerge(caller, %s, %s, %s\n", serv_uaddr,
130 clnt_uaddr, netid);
131 #endif
132 nconf = getnetconfigent(netid);
133 if (nconf == NULL)
134 return NULL;
135
136 /*
137 * Local merge, just return a duplicate.
138 */
139 if (clnt_uaddr != NULL && strncmp(clnt_uaddr, "0.0.0.0.", 8) == 0)
140 return strdup(clnt_uaddr);
141
142 serv_nbp = uaddr2taddr(nconf, serv_uaddr);
143 if (serv_nbp == NULL)
144 return NULL;
145
146 serv_sa = (struct sockaddr *)serv_nbp->buf;
147 if (clnt_uaddr != NULL) {
148 clnt_nbp = uaddr2taddr(nconf, clnt_uaddr);
149 if (clnt_nbp == NULL) {
150 free(serv_nbp);
151 return NULL;
152 }
153 clnt_sa = (struct sockaddr *)clnt_nbp->buf;
154 if (clnt_sa->sa_family == AF_LOCAL) {
155 free(serv_nbp);
156 free(clnt_nbp);
157 free(clnt_sa);
158 return strdup(serv_uaddr);
159 }
160 } else {
161 clnt_sa = (struct sockaddr *)
162 malloc(sizeof (struct sockaddr_storage));
163 memcpy(clnt_sa, clnt, clnt->sa_len);
164 }
165
166 if (getifaddrs(&ifp) < 0) {
167 free(serv_nbp);
168 free(clnt_sa);
169 if (clnt_nbp != NULL)
170 free(clnt_nbp);
171 return 0;
172 }
173
174 /*
175 * Loop through all interfaces. For each interface, see if the
176 * network portion of its address is equal to that of the client.
177 * If so, we have found the interface that we want to use.
178 */
179 for (ifap = ifp; ifap != NULL; ifap = ifap->ifa_next) {
180 if (ifap->ifa_addr->sa_family != clnt->sa_family ||
181 !(ifap->ifa_flags & IFF_UP))
182 continue;
183
184 switch (clnt->sa_family) {
185 case AF_INET:
186 /*
187 * realsin: address that recvfrom gave us.
188 * ifsin: address of interface being examined.
189 * clntsin: address that client want us to contact
190 * it on
191 * servsin: local address of RPC service.
192 * sinmask: netmask of this interface
193 * newsin: initially a copy of clntsin, eventually
194 * the merged address
195 */
196 servsin = (struct sockaddr_in *)serv_sa;
197 clntsin = (struct sockaddr_in *)clnt_sa;
198 sinmask = (struct sockaddr_in *)ifap->ifa_netmask;
199 newsin = (struct sockaddr_in *)&ss;
200 ifsin = (struct sockaddr_in *)ifap->ifa_addr;
201 if (!bitmaskcmp(&ifsin->sin_addr, &clntsin->sin_addr,
202 &sinmask->sin_addr, sizeof (struct in_addr))) {
203 goto found;
204 }
205 break;
206 #ifdef INET6
207 case AF_INET6:
208 /*
209 * realsin6: address that recvfrom gave us.
210 * ifsin6: address of interface being examined.
211 * clntsin6: address that client want us to contact
212 * it on
213 * servsin6: local address of RPC service.
214 * sin6mask: netmask of this interface
215 * newsin6: initially a copy of clntsin, eventually
216 * the merged address
217 *
218 * For v6 link local addresses, if the client contacted
219 * us via a link-local address, and wants us to reply
220 * to one, use the scope id to see which one.
221 */
222 realsin6 = (struct sockaddr_in6 *)clnt;
223 ifsin6 = (struct sockaddr_in6 *)ifap->ifa_addr;
224 in6_fillscopeid(ifsin6);
225 clntsin6 = (struct sockaddr_in6 *)clnt_sa;
226 servsin6 = (struct sockaddr_in6 *)serv_sa;
227 sin6mask = (struct sockaddr_in6 *)ifap->ifa_netmask;
228 newsin6 = (struct sockaddr_in6 *)&ss;
229 if (IN6_IS_ADDR_LINKLOCAL(&ifsin6->sin6_addr) &&
230 IN6_IS_ADDR_LINKLOCAL(&realsin6->sin6_addr) &&
231 IN6_IS_ADDR_LINKLOCAL(&clntsin6->sin6_addr)) {
232 if (ifsin6->sin6_scope_id !=
233 realsin6->sin6_scope_id)
234 continue;
235 goto found;
236 }
237 if (!bitmaskcmp(&ifsin6->sin6_addr,
238 &clntsin6->sin6_addr, &sin6mask->sin6_addr,
239 sizeof (struct in6_addr)))
240 goto found;
241 break;
242 #endif
243 default:
244 goto freeit;
245 }
246 }
247 /*
248 * Didn't find anything. Get the first possibly useful interface,
249 * preferring "normal" interfaces to point-to-point and loopback
250 * ones.
251 */
252 bestif = NULL;
253 for (ifap = ifp; ifap != NULL; ifap = ifap->ifa_next) {
254 if (ifap->ifa_addr->sa_family != clnt->sa_family ||
255 !(ifap->ifa_flags & IFF_UP))
256 continue;
257 if (!(ifap->ifa_flags & IFF_LOOPBACK) &&
258 !(ifap->ifa_flags & IFF_POINTOPOINT)) {
259 bestif = ifap;
260 break;
261 }
262 if (bestif == NULL)
263 bestif = ifap;
264 else if ((bestif->ifa_flags & IFF_LOOPBACK) &&
265 !(ifap->ifa_flags & IFF_LOOPBACK))
266 bestif = ifap;
267 }
268 ifap = bestif;
269 found:
270 switch (clnt->sa_family) {
271 case AF_INET:
272 memcpy(newsin, ifap->ifa_addr, clnt_sa->sa_len);
273 newsin->sin_port = servsin->sin_port;
274 tbuf.len = clnt_sa->sa_len;
275 tbuf.maxlen = sizeof (struct sockaddr_storage);
276 tbuf.buf = newsin;
277 break;
278 #ifdef INET6
279 case AF_INET6:
280 assert(newsin6);
281 memcpy(newsin6, ifsin6, clnt_sa->sa_len);
282 newsin6->sin6_port = servsin6->sin6_port;
283 tbuf.maxlen = sizeof (struct sockaddr_storage);
284 tbuf.len = clnt_sa->sa_len;
285 tbuf.buf = newsin6;
286 break;
287 #endif
288 default:
289 goto freeit;
290 }
291 if (ifap != NULL)
292 ret = taddr2uaddr(nconf, &tbuf);
293 freeit:
294 freenetconfigent(nconf);
295 free(serv_sa);
296 free(serv_nbp);
297 if (clnt_sa != NULL)
298 free(clnt_sa);
299 if (clnt_nbp != NULL)
300 free(clnt_nbp);
301 freeifaddrs(ifp);
302
303 #ifdef RPCBIND_DEBUG
304 if (debugging)
305 fprintf(stderr, "addrmerge: returning %s\n", ret);
306 #endif
307 return ret;
308 }
309
310 void
network_init()311 network_init()
312 {
313 #ifdef INET6
314 struct ifaddrs *ifap, *ifp;
315 struct ipv6_mreq mreq6;
316 int ifindex, s;
317 #endif
318 int ecode;
319 struct addrinfo hints, *res;
320
321 memset(&hints, 0, sizeof hints);
322 hints.ai_family = AF_INET;
323 if ((ecode = getaddrinfo(NULL, "sunrpc", &hints, &res))) {
324 if (debugging)
325 fprintf(stderr, "can't get local ip4 address: %s\n",
326 gai_strerror(ecode));
327 } else {
328 local_in4 = (struct sockaddr_in *)malloc(sizeof *local_in4);
329 if (local_in4 == NULL) {
330 if (debugging)
331 fprintf(stderr, "can't alloc local ip4 addr\n");
332 }
333 memcpy(local_in4, res->ai_addr, sizeof *local_in4);
334 }
335
336 #ifdef INET6
337 hints.ai_family = AF_INET6;
338 if ((ecode = getaddrinfo(NULL, "sunrpc", &hints, &res))) {
339 if (debugging)
340 fprintf(stderr, "can't get local ip6 address: %s\n",
341 gai_strerror(ecode));
342 } else {
343 local_in6 = (struct sockaddr_in6 *)malloc(sizeof *local_in6);
344 if (local_in6 == NULL) {
345 if (debugging)
346 fprintf(stderr, "can't alloc local ip6 addr\n");
347 }
348 memcpy(local_in6, res->ai_addr, sizeof *local_in6);
349 }
350
351 /*
352 * Now join the RPC ipv6 multicast group on all interfaces.
353 */
354 if (getifaddrs(&ifp) < 0)
355 return;
356
357 mreq6.ipv6mr_interface = 0;
358 inet_pton(AF_INET6, RPCB_MULTICAST_ADDR, &mreq6.ipv6mr_multiaddr);
359
360 s = socket(AF_INET6, SOCK_DGRAM, IPPROTO_UDP);
361
362 /*
363 * Loop through all interfaces. For each interface, see if the
364 * network portion of its address is equal to that of the client.
365 * If so, we have found the interface that we want to use.
366 */
367 for (ifap = ifp; ifap != NULL; ifap = ifap->ifa_next) {
368 if (ifap->ifa_addr->sa_family != AF_INET6 ||
369 !(ifap->ifa_flags & IFF_MULTICAST))
370 continue;
371 ifindex = if_nametoindex(ifap->ifa_name);
372 if (ifindex == mreq6.ipv6mr_interface)
373 /*
374 * Already did this one.
375 */
376 continue;
377 mreq6.ipv6mr_interface = ifindex;
378 if (setsockopt(s, IPPROTO_IPV6, IPV6_JOIN_GROUP, &mreq6,
379 sizeof mreq6) < 0)
380 if (debugging)
381 warn("setsockopt v6 multicast");
382 }
383 #endif
384
385 /* close(s); */
386 }
387
388 struct sockaddr *
local_sa(int af)389 local_sa(int af)
390 {
391 switch (af) {
392 case AF_INET:
393 return (struct sockaddr *)local_in4;
394 #ifdef INET6
395 case AF_INET6:
396 return (struct sockaddr *)local_in6;
397 #endif
398 default:
399 return NULL;
400 }
401 }
402