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, "disable_ipv6", "1");
152 sysctl_interface(ifname, "accept_ra", "2");
153 sysctl_interface(ifname, "disable_ipv6", "0");
157 openlog("odhcp6c", LOG_PID, LOG_DAEMON); // Disable LOG_PERROR
159 syslog(LOG_ERR, "Failed to daemonize: %s",
166 snprintf(pidbuf, sizeof(pidbuf),
167 "/var/run/odhcp6c.%s.pid", ifname);
171 int fd = open(pidfile, O_WRONLY | O_CREAT);
174 int len = snprintf(buf, sizeof(buf), "%i\n", getpid());
180 while (do_signal != SIGTERM) { // Main logic
181 odhcp6c_clear_state(STATE_SERVER_ID);
182 odhcp6c_clear_state(STATE_SERVER_CAND);
183 odhcp6c_clear_state(STATE_IA_PD);
184 odhcp6c_clear_state(STATE_IA_PD_LOST);
185 dhcpv6_set_ia_na_mode(ia_na_mode);
189 int res = dhcpv6_request(DHCPV6_MSG_SOLICIT);
192 continue; // Might happen if we got a signal
193 } else if (res == DHCPV6_STATELESS) { // Stateless mode
194 while (do_signal == 0 || do_signal == SIGUSR1) {
197 res = dhcpv6_request(DHCPV6_MSG_INFO_REQ);
198 if (do_signal == SIGUSR1)
203 script_call("informed");
206 if (dhcpv6_poll_reconfigure() > 0)
207 script_call("informed");
210 if (do_signal == SIGALRM)
211 script_call("timeout");
217 if (dhcpv6_request(DHCPV6_MSG_REQUEST) < 0)
220 script_call("bound");
223 while (do_signal == 0 || do_signal == SIGUSR1) {
225 // Wait for T1 to expire or until we get a reconfigure
226 int res = dhcpv6_poll_reconfigure();
229 script_call("updated");
234 // Handle signal, if necessary
235 if (do_signal == SIGUSR1)
236 do_signal = 0; // Acknowledged
237 else if (do_signal > 0)
238 break; // Other signal type
240 size_t ia_pd_len, ia_na_len, ia_pd_new, ia_na_new;
241 odhcp6c_get_state(STATE_IA_PD, &ia_pd_len);
242 odhcp6c_get_state(STATE_IA_NA, &ia_na_len);
244 // If we have any IAs, send renew, otherwise request
246 if (ia_pd_len == 0 && ia_na_len == 0)
247 r = dhcpv6_request(DHCPV6_MSG_REQUEST);
249 r = dhcpv6_request(DHCPV6_MSG_RENEW);
250 if (r > 0) // Publish updates
251 script_call("updated");
253 continue; // Renew was successful
255 odhcp6c_clear_state(STATE_SERVER_ID); // Remove binding
257 // If we have IAs, try rebind otherwise restart
258 res = dhcpv6_request(DHCPV6_MSG_REBIND);
260 odhcp6c_get_state(STATE_IA_PD, &ia_pd_new);
261 odhcp6c_get_state(STATE_IA_NA, &ia_na_new);
262 if (res < 0 || (ia_pd_new == 0 && ia_pd_len) ||
263 (ia_na_new == 0 && ia_na_len))
264 break; // We lost all our IAs, restart
266 script_call("rebound");
270 size_t ia_pd_len, ia_na_len, server_id_len;
271 uint8_t *ia_pd = odhcp6c_get_state(STATE_IA_PD, &ia_pd_len);
272 odhcp6c_get_state(STATE_IA_NA, &ia_na_len);
273 odhcp6c_get_state(STATE_SERVER_ID, &server_id_len);
275 // Add all prefixes to lost prefixes
276 odhcp6c_add_state(STATE_IA_PD_LOST, ia_pd, ia_pd_len);
277 odhcp6c_clear_state(STATE_IA_PD);
279 if (do_signal == SIGALRM)
280 script_call("timeout");
282 script_call("unbound");
284 // Remove assigned addresses
286 dhcpv6_remove_addrs();
288 if (server_id_len > 0 && (ia_pd_len > 0 || ia_na_len > 0))
289 dhcpv6_request(DHCPV6_MSG_RELEASE);
296 static int usage(void)
299 "Usage: odhcp6c [options] <interface>\n"
300 "\nFeature options:\n"
301 " -N <mode> Mode for requesting addresses [try|force|none]\n"
302 " -P <length> Request IPv6-Prefix (0 = auto)\n"
303 " -c <clientid> Override client-ID (base-16 encoded)\n"
304 " -r <options> Options to be requested (comma-separated)\n"
305 " -s <script> Status update script (/usr/sbin/odhcp6c-update)\n"
306 " -t <timeout> Request timeout after which the script is called\n"
307 "\nInvocation options:\n"
308 " -p <pidfile> Set pidfile (/var/run/6relayd.pid)\n"
310 //" -v Increase logging verbosity\n"
311 " -h Show this help\n\n";
312 write(STDERR_FILENO, buf, sizeof(buf));
317 // Don't want to pull-in librt and libpthread just for a monotonic clock...
318 uint64_t adhc6c_get_milli_time(void)
320 struct timespec t = {0, 0};
321 syscall(SYS_clock_gettime, CLOCK_MONOTONIC, &t);
322 return t.tv_sec * 1000 + t.tv_nsec / 1000000;
326 static uint8_t* odhcp6c_resize_state(enum odhcp6c_state state, ssize_t len)
329 return state_data[state] + state_len[state];
331 uint8_t *n = realloc(state_data[state], state_len[state] + len);
332 if (n || state_len[state] + len == 0) {
333 state_data[state] = n;
334 n += state_len[state];
335 state_len[state] += len;
341 bool odhcp6c_signal_is_pending(void)
343 return do_signal != 0;
347 void odhcp6c_clear_state(enum odhcp6c_state state)
349 state_len[state] = 0;
353 void odhcp6c_add_state(enum odhcp6c_state state, const void *data, size_t len)
355 uint8_t *n = odhcp6c_resize_state(state, len);
357 memcpy(n, data, len);
361 size_t odhcp6c_remove_state(enum odhcp6c_state state, size_t offset, size_t len)
363 uint8_t *data = state_data[state];
364 ssize_t len_after = state_len[state] - (offset + len);
366 return state_len[state];
368 memmove(data + offset, data + offset + len, len_after);
369 return state_len[state] -= len;
373 bool odhcp6c_commit_state(enum odhcp6c_state state, size_t old_len)
375 size_t new_len = state_len[state] - old_len;
376 uint8_t *old_data = state_data[state], *new_data = old_data + old_len;
377 bool upd = new_len != old_len || memcmp(old_data, new_data, new_len);
379 memmove(old_data, new_data, new_len);
380 odhcp6c_resize_state(state, -old_len);
386 void* odhcp6c_get_state(enum odhcp6c_state state, size_t *len)
388 *len = state_len[state];
389 return state_data[state];
393 static int sysctl_interface(const char *ifname, const char *option,
397 const char *sysctl_pattern = "/proc/sys/net/ipv6/conf/%s/%s";
398 snprintf(pathbuf, sizeof(pathbuf), sysctl_pattern, ifname, option);
400 int fd = open(pathbuf, O_WRONLY);
401 int written = write(fd, data, strlen(data));
404 return (written > 0) ? 0 : -1;
408 static void sighandler(int signal)
410 if (signal == SIGCHLD)
411 while (waitpid(-1, NULL, WNOHANG) > 0);
412 else if (signal == SIGUSR1)
414 else if (signal == SIGUSR2)
416 else if (signal == SIGALRM)