2 * Copyright (C) 2012 Steven Barth <steven@midlink.org>
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License v2 as published by
6 * the Free Software Foundation.
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11 * GNU General Public License for more details.
28 #include <sys/syscall.h>
33 static void sighandler(int signal);
34 static int sysctl_interface(const char *ifname, const char *option,
36 static int usage(void);
39 static uint8_t *state_data[_STATE_MAX] = {NULL};
40 static size_t state_len[_STATE_MAX] = {0};
42 static volatile int do_signal = 0;
45 int main(_unused int argc, char* const argv[])
47 openlog("odhcp6c", LOG_PERROR | LOG_PID, LOG_DAEMON);
49 // Allocate ressources
50 const char *pidfile = NULL;
51 const char *script = "/usr/sbin/odhcp6c-update";
56 enum odhcp6c_ia_mode ia_na_mode = IA_MODE_TRY;
58 bool help = false, daemonize = false, reset = false;
59 int c, request_pd = 0, timeout = 0;
60 while ((c = getopt(argc, argv, "RN:P:c:r:s:t:hdp:")) != -1) {
67 if (!strcmp(optarg, "force"))
68 ia_na_mode = IA_MODE_FORCE;
69 else if (!strcmp(optarg, "none"))
70 ia_na_mode = IA_MODE_NONE;
71 else if (!strcmp(optarg, "try"))
72 ia_na_mode = IA_MODE_TRY;
78 request_pd = strtoul(optarg, NULL, 10);
84 l = script_unhexlify(&buf[4], sizeof(buf) - 4, optarg);
87 buf[1] = DHCPV6_OPT_CLIENTID;
90 odhcp6c_add_state(STATE_CLIENT_ID, buf, l + 4);
99 opttype = htons(strtoul(optarg, &optpos, 10));
100 if (optpos == optarg)
104 odhcp6c_add_state(STATE_ORO, &opttype, 2);
113 timeout = strtoul(optarg, NULL, 10);
130 const char *ifname = argv[optind];
135 if (init_dhcpv6(ifname, request_pd) || init_rtnetlink() ||
136 script_init(script, ifname)) {
137 syslog(LOG_ERR, "failed to initialize: %s", strerror(errno));
141 signal(SIGHUP, sighandler);
142 signal(SIGINT, sighandler);
143 signal(SIGALRM, sighandler);
144 signal(SIGCHLD, sighandler);
145 signal(SIGTERM, sighandler);
146 signal(SIGUSR1, sighandler);
147 signal(SIGUSR2, sighandler);
149 // Configure interface to accept RA
151 sysctl_interface(ifname, "accept_ra", "2");
152 sysctl_interface(ifname, "disable_ipv6", "1");
153 struct timespec ts = {1, 0};
154 nanosleep(&ts, NULL);
155 sysctl_interface(ifname, "disable_ipv6", "0");
159 openlog("odhcp6c", LOG_PID, LOG_DAEMON); // Disable LOG_PERROR
161 syslog(LOG_ERR, "Failed to daemonize: %s",
168 snprintf(pidbuf, sizeof(pidbuf),
169 "/var/run/odhcp6c.%s.pid", ifname);
173 int fd = open(pidfile, O_WRONLY | O_CREAT);
176 int len = snprintf(buf, sizeof(buf), "%i\n", getpid());
182 while (do_signal != SIGTERM) { // Main logic
183 odhcp6c_clear_state(STATE_SERVER_ID);
184 odhcp6c_clear_state(STATE_SERVER_CAND);
185 odhcp6c_clear_state(STATE_IA_PD);
186 odhcp6c_clear_state(STATE_IA_PD_LOST);
187 dhcpv6_set_ia_na_mode(ia_na_mode);
191 int res = dhcpv6_request(DHCPV6_MSG_SOLICIT);
194 continue; // Might happen if we got a signal
195 } else if (res == DHCPV6_STATELESS) { // Stateless mode
196 while (do_signal == 0 || do_signal == SIGUSR1) {
199 res = dhcpv6_request(DHCPV6_MSG_INFO_REQ);
200 if (do_signal == SIGUSR1)
205 script_call("informed");
208 if (dhcpv6_poll_reconfigure() > 0)
209 script_call("informed");
212 if (do_signal == SIGALRM)
213 script_call("timeout");
219 if (dhcpv6_request(DHCPV6_MSG_REQUEST) < 0)
222 script_call("bound");
225 while (do_signal == 0 || do_signal == SIGUSR1) {
227 // Wait for T1 to expire or until we get a reconfigure
228 int res = dhcpv6_poll_reconfigure();
231 script_call("updated");
236 // Handle signal, if necessary
237 if (do_signal == SIGUSR1)
238 do_signal = 0; // Acknowledged
239 else if (do_signal > 0)
240 break; // Other signal type
242 size_t ia_pd_len, ia_na_len, ia_pd_new, ia_na_new;
243 odhcp6c_get_state(STATE_IA_PD, &ia_pd_len);
244 odhcp6c_get_state(STATE_IA_NA, &ia_na_len);
246 // If we have any IAs, send renew, otherwise request
248 if (ia_pd_len == 0 && ia_na_len == 0)
249 r = dhcpv6_request(DHCPV6_MSG_REQUEST);
251 r = dhcpv6_request(DHCPV6_MSG_RENEW);
252 if (r > 0) // Publish updates
253 script_call("updated");
255 continue; // Renew was successful
257 odhcp6c_clear_state(STATE_SERVER_ID); // Remove binding
259 // If we have IAs, try rebind otherwise restart
260 res = dhcpv6_request(DHCPV6_MSG_REBIND);
262 odhcp6c_get_state(STATE_IA_PD, &ia_pd_new);
263 odhcp6c_get_state(STATE_IA_NA, &ia_na_new);
264 if (res < 0 || (ia_pd_new == 0 && ia_pd_len) ||
265 (ia_na_new == 0 && ia_na_len))
266 break; // We lost all our IAs, restart
268 script_call("rebound");
272 size_t ia_pd_len, ia_na_len, server_id_len;
273 uint8_t *ia_pd = odhcp6c_get_state(STATE_IA_PD, &ia_pd_len);
274 odhcp6c_get_state(STATE_IA_NA, &ia_na_len);
275 odhcp6c_get_state(STATE_SERVER_ID, &server_id_len);
277 // Add all prefixes to lost prefixes
278 odhcp6c_add_state(STATE_IA_PD_LOST, ia_pd, ia_pd_len);
279 odhcp6c_clear_state(STATE_IA_PD);
281 if (do_signal == SIGALRM)
282 script_call("timeout");
284 script_call("unbound");
286 // Remove assigned addresses
288 dhcpv6_remove_addrs();
290 if (server_id_len > 0 && (ia_pd_len > 0 || ia_na_len > 0))
291 dhcpv6_request(DHCPV6_MSG_RELEASE);
298 static int usage(void)
301 "Usage: odhcp6c [options] <interface>\n"
302 "\nFeature options:\n"
303 " -N <mode> Mode for requesting addresses [try|force|none]\n"
304 " -P <length> Request IPv6-Prefix (0 = auto)\n"
305 " -c <clientid> Override client-ID (base-16 encoded)\n"
306 " -r <options> Options to be requested (comma-separated)\n"
307 " -s <script> Status update script (/usr/sbin/odhcp6c-update)\n"
308 " -t <timeout> Request timeout after which the script is called\n"
309 "\nInvocation options:\n"
310 " -p <pidfile> Set pidfile (/var/run/6relayd.pid)\n"
312 //" -v Increase logging verbosity\n"
313 " -h Show this help\n\n";
314 write(STDERR_FILENO, buf, sizeof(buf));
319 // Don't want to pull-in librt and libpthread just for a monotonic clock...
320 uint64_t adhc6c_get_milli_time(void)
322 struct timespec t = {0, 0};
323 syscall(SYS_clock_gettime, CLOCK_MONOTONIC, &t);
324 return t.tv_sec * 1000 + t.tv_nsec / 1000000;
328 static uint8_t* odhcp6c_resize_state(enum odhcp6c_state state, ssize_t len)
331 return state_data[state] + state_len[state];
333 uint8_t *n = realloc(state_data[state], state_len[state] + len);
334 if (n || state_len[state] + len == 0) {
335 state_data[state] = n;
336 n += state_len[state];
337 state_len[state] += len;
343 bool odhcp6c_signal_is_pending(void)
345 return do_signal != 0;
349 void odhcp6c_clear_state(enum odhcp6c_state state)
351 state_len[state] = 0;
355 void odhcp6c_add_state(enum odhcp6c_state state, const void *data, size_t len)
357 uint8_t *n = odhcp6c_resize_state(state, len);
359 memcpy(n, data, len);
363 size_t odhcp6c_remove_state(enum odhcp6c_state state, size_t offset, size_t len)
365 uint8_t *data = state_data[state];
366 ssize_t len_after = state_len[state] - (offset + len);
368 return state_len[state];
370 memmove(data + offset, data + offset + len, len_after);
371 return state_len[state] -= len;
375 bool odhcp6c_commit_state(enum odhcp6c_state state, size_t old_len)
377 size_t new_len = state_len[state] - old_len;
378 uint8_t *old_data = state_data[state], *new_data = old_data + old_len;
379 bool upd = new_len != old_len || memcmp(old_data, new_data, new_len);
381 memmove(old_data, new_data, new_len);
382 odhcp6c_resize_state(state, -old_len);
388 void* odhcp6c_get_state(enum odhcp6c_state state, size_t *len)
390 *len = state_len[state];
391 return state_data[state];
395 static int sysctl_interface(const char *ifname, const char *option,
399 const char *sysctl_pattern = "/proc/sys/net/ipv6/conf/%s/%s";
400 snprintf(pathbuf, sizeof(pathbuf), sysctl_pattern, ifname, option);
402 int fd = open(pathbuf, O_WRONLY);
403 int written = write(fd, data, strlen(data));
406 return (written > 0) ? 0 : -1;
410 static void sighandler(int signal)
412 if (signal == SIGCHLD)
413 while (waitpid(-1, NULL, WNOHANG) > 0);
414 else if (signal == SIGUSR1)
416 else if (signal == SIGUSR2)
418 else if (signal == SIGALRM)