1 /*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21 /*
22 * Copyright 2009 Sun Microsystems, Inc. All rights reserved.
23 * Use is subject to license terms.
24 */
25
26 #include <sys/socket.h>
27 #include <sys/stream.h>
28 #include <sys/param.h>
29
30 #include <net/route.h>
31 #include <net/if.h>
32 #include <netinet/in.h>
33 #include <arpa/inet.h>
34
35 #include <locale.h>
36
37 #include <errno.h>
38 #include <unistd.h>
39 #include <stdio.h>
40 #include <stdlib.h>
41 #include <strings.h>
42 #include <string.h>
43 #include <stropts.h>
44 #include <fcntl.h>
45 #include <libdliptun.h>
46
47 static void usage(void);
48
49 static dladm_handle_t handle;
50 /* booleans corresponding to command line flags */
51 static boolean_t eflag = B_FALSE;
52 static boolean_t dflag = B_FALSE;
53 static boolean_t aflag = B_FALSE;
54
55
56 /*
57 * printkstatus()
58 *
59 * Queries the kernel for the current 6to4 Relay Router value, prints
60 * a status message based on the value and exits this command.
61 * INADDR_ANY is used to denote that Relay Router communication support is
62 * disabled within the kernel.
63 */
64 static void
printkstatus(void)65 printkstatus(void)
66 {
67 struct in_addr rr_addr;
68 char buf[INET6_ADDRSTRLEN];
69 char errstr[DLADM_STRSIZE];
70 dladm_status_t status;
71
72 status = dladm_iptun_get6to4relay(handle, &rr_addr);
73 if (status != DLADM_STATUS_OK) {
74 (void) fprintf(stderr, gettext("6to4relay: unable to get "
75 "6to4 relay status: %s\n"),
76 dladm_status2str(status, errstr));
77 return;
78 }
79 (void) printf("6to4relay: ");
80 if (rr_addr.s_addr == INADDR_ANY) {
81 (void) printf(gettext("6to4 Relay Router communication "
82 "support is disabled.\n"));
83 } else {
84 (void) printf(gettext("6to4 Relay Router communication "
85 "support is enabled.\n"));
86 (void) printf(gettext("IPv4 destination address of Relay "
87 "Router = "));
88 (void) printf("%s\n",
89 inet_ntop(AF_INET, &rr_addr, buf, sizeof (buf)));
90 }
91 }
92
93 /*
94 * modifyroute(cmd, in_gw)
95 *
96 * Modifies a default IPv6 route with DST = ::, GATEWAY = in_gw, NETMASK = ::
97 * and flags = <GATEWAY, STATIC>.
98 * This route is to be propagated through the 6to4 site so that 6to4 hosts
99 * can send packets to native IPv6 hosts behind a remote 6to4 Relay Router.
100 */
101 static void
modifyroute(unsigned int cmd,in6_addr_t * in_gw)102 modifyroute(unsigned int cmd, in6_addr_t *in_gw)
103 {
104 static int rtmseq;
105 int rtsock;
106 int rlen;
107
108 static struct {
109 struct rt_msghdr rt_hdr;
110 struct sockaddr_in6 rt_dst;
111 struct sockaddr_in6 rt_gate;
112 struct sockaddr_in6 rt_mask;
113 } rt_msg;
114
115 /* Open a routing socket for passing route commands */
116 if ((rtsock = socket(AF_ROUTE, SOCK_RAW, AF_INET)) < 0) {
117 (void) fprintf(stderr, gettext("6to4relay: unable to modify "
118 "default IPv6 route: socket: %s\n"), strerror(errno));
119 return;
120 }
121
122 (void) memset(&rt_msg, 0, sizeof (rt_msg));
123 rt_msg.rt_hdr.rtm_msglen = sizeof (rt_msg);
124 rt_msg.rt_hdr.rtm_version = RTM_VERSION;
125 rt_msg.rt_hdr.rtm_addrs = RTA_DST | RTA_GATEWAY | RTA_NETMASK;
126 rt_msg.rt_hdr.rtm_pid = getpid();
127 rt_msg.rt_hdr.rtm_type = cmd;
128 rt_msg.rt_hdr.rtm_seq = ++rtmseq;
129 rt_msg.rt_hdr.rtm_flags = RTF_STATIC | RTF_GATEWAY;
130
131 /* DST */
132 rt_msg.rt_dst.sin6_family = AF_INET6;
133 (void) memset(&rt_msg.rt_dst.sin6_addr.s6_addr, 0,
134 sizeof (in6_addr_t));
135
136 /* GATEWAY */
137 rt_msg.rt_gate.sin6_family = AF_INET6;
138 bcopy(in_gw->s6_addr, &rt_msg.rt_gate.sin6_addr.s6_addr,
139 sizeof (in6_addr_t));
140
141 /* NETMASK */
142 rt_msg.rt_mask.sin6_family = AF_INET6;
143 (void) memset(&rt_msg.rt_mask.sin6_addr.s6_addr, 0,
144 sizeof (in6_addr_t));
145
146 /* Send the routing message */
147 rlen = write(rtsock, &rt_msg, rt_msg.rt_hdr.rtm_msglen);
148 if (rlen < rt_msg.rt_hdr.rtm_msglen) {
149 if (rlen < 0) {
150 (void) fprintf(stderr,
151 gettext("6to4relay: write to routing socket: %s\n"),
152 strerror(errno));
153 } else {
154 (void) fprintf(stderr, gettext("6to4relay: write to "
155 "routing socket got only %d for rlen\n"), rlen);
156 }
157 }
158 (void) close(rtsock);
159 }
160
161 static void
usage(void)162 usage(void)
163 {
164 (void) fprintf(stderr,
165 gettext("usage:\n"
166 "\t6to4relay\n"
167 "\t6to4relay -e [-a <addr>]\n"
168 "\t6to4relay -d\n"
169 "\t6to4relay -h\n"));
170 }
171
172 int
main(int argc,char ** argv)173 main(int argc, char **argv)
174 {
175 int ch;
176 char *relay_arg = NULL;
177 dladm_status_t status;
178 char errstr[DLADM_STRSIZE];
179
180 (void) setlocale(LC_ALL, "");
181
182 #if !defined(TEXT_DOMAIN)
183 #define TEXT_DOMAIN "SYS_TEST"
184 #endif
185 (void) textdomain(TEXT_DOMAIN);
186
187 if ((status = dladm_open(&handle)) != DLADM_STATUS_OK) {
188 (void) fprintf(stderr, gettext("6to4relay: error opening "
189 "dladm handle: %s\n"), dladm_status2str(status, errstr));
190 return (EXIT_FAILURE);
191 }
192
193 /* If no args are specified, print the current status. */
194 if (argc < 2) {
195 printkstatus();
196 return (EXIT_SUCCESS);
197 }
198
199 while ((ch = getopt(argc, argv, "ea:dh")) != EOF) {
200 switch (ch) {
201 case 'e':
202 eflag = B_TRUE;
203 break;
204 case 'd':
205 dflag = B_TRUE;
206 break;
207 case 'a':
208 aflag = B_TRUE;
209 relay_arg = optarg;
210 break;
211 case 'h':
212 usage();
213 return (EXIT_SUCCESS);
214 default:
215 usage();
216 return (EXIT_FAILURE);
217 }
218 }
219 /*
220 * If -a is specified, -e must also be specified. Also, the
221 * combination of -e and -d is illegal. Fail on either case.
222 */
223 if ((aflag && !eflag) || (eflag && dflag)) {
224 usage();
225 return (EXIT_FAILURE);
226 }
227
228 /*
229 * Enable Relay Router communication support in the kernel.
230 */
231 if (eflag) {
232 struct in_addr current_addr;
233 struct in_addr new_addr;
234 in6_addr_t v6_rt;
235
236 /*
237 * if -a was not specified, the well-known anycast will
238 * be used.
239 */
240 if (!aflag) {
241 new_addr.s_addr = htonl(INADDR_6TO4RRANYCAST);
242 } else if (inet_pton(AF_INET, relay_arg, &new_addr) <= 0) {
243 (void) fprintf(stderr, gettext("6to4relay: input "
244 "address (%s) is not a valid IPv4 dotted-decimal "
245 "string.\n"), relay_arg);
246 return (EXIT_FAILURE);
247 }
248
249 status = dladm_iptun_get6to4relay(handle, ¤t_addr);
250 if (status != DLADM_STATUS_OK) {
251 (void) fprintf(stderr, gettext("6to4relay: "
252 "unable to obtain current 6to4 relay address: %s"),
253 dladm_status2str(status, errstr));
254 return (EXIT_FAILURE);
255 }
256
257 if (current_addr.s_addr == new_addr.s_addr)
258 return (EXIT_SUCCESS);
259
260 status = dladm_iptun_set6to4relay(handle, &new_addr);
261 if (status != DLADM_STATUS_OK) {
262 (void) fprintf(stderr, gettext("6to4relay: "
263 "unable to set the 6to4 relay router address: "
264 "%s\n"), dladm_status2str(status, errstr));
265 return (EXIT_FAILURE);
266 }
267
268 if (current_addr.s_addr != INADDR_ANY) {
269 /* remove old default IPv6 route */
270 IN6_V4ADDR_TO_6TO4(¤t_addr, &v6_rt);
271 modifyroute(RTM_DELETE, &v6_rt);
272 }
273
274 IN6_V4ADDR_TO_6TO4(&new_addr, &v6_rt);
275 modifyroute(RTM_ADD, &v6_rt);
276 }
277
278 /*
279 * Disable Relay Router communication support in kernel.
280 */
281 if (dflag) {
282 struct in_addr rr_addr;
283 in6_addr_t v6_rt;
284
285 /*
286 * get Relay Router address from the kernel and delete
287 * default IPv6 route that was added for it.
288 */
289 status = dladm_iptun_get6to4relay(handle, &rr_addr);
290 if (status != DLADM_STATUS_OK) {
291 (void) fprintf(stderr, gettext("6to4relay: "
292 "unable to obtain current 6to4 relay address: %s"),
293 dladm_status2str(status, errstr));
294 return (EXIT_FAILURE);
295 }
296 if (rr_addr.s_addr == INADDR_ANY)
297 return (EXIT_SUCCESS);
298
299 IN6_V4ADDR_TO_6TO4(&rr_addr, &v6_rt);
300 modifyroute(RTM_DELETE, &v6_rt);
301
302 /*
303 * INADDR_ANY (0.0.0.0) is used by the kernel to disable Relay
304 * Router communication support.
305 */
306 rr_addr.s_addr = INADDR_ANY;
307 status = dladm_iptun_set6to4relay(handle, &rr_addr);
308 if (status != DLADM_STATUS_OK) {
309 (void) fprintf(stderr, gettext("6to4relay: "
310 "unable to disable tunneling to 6to4 relay router: "
311 "%s\n"), dladm_status2str(status, errstr));
312 return (EXIT_FAILURE);
313 }
314 }
315
316 return (EXIT_SUCCESS);
317 }
318