2 * Copyright (c) 2008, 2009 Nicira Networks.
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at:
8 * http://www.apache.org/licenses/LICENSE-2.0
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
24 #include "command-line.h"
26 #include "dhcp-client.h"
29 #include "dynamic-string.h"
30 #include "fatal-signal.h"
32 #include "poll-loop.h"
38 #define THIS_MODULE VLM_ovs_discover
42 struct dhclient *dhcp;
45 /* The interfaces that we serve. */
46 static struct iface *ifaces;
49 /* --accept-vconn: Regular expression specifying the class of controller vconns
50 * that we will accept during autodiscovery. */
51 static const char *accept_controller_re = ".*";
52 static regex_t accept_controller_regex;
54 /* --exit-without-bind: Exit after discovering the controller, without binding
55 * the network device to an IP address? */
56 static bool exit_without_bind;
58 /* --exit-after-bind: Exit after discovering the controller, after binding the
59 * network device to an IP address? */
60 static bool exit_after_bind;
62 static bool iface_init(struct iface *, const char *netdev_name);
63 static void release_ifaces(void *aux UNUSED);
65 static void parse_options(int argc, char *argv[]);
66 static void usage(void) NO_RETURN;
68 static void modify_dhcp_request(struct dhcp_msg *, void *aux);
69 static bool validate_dhcp_offer(const struct dhcp_msg *, void *aux);
72 main(int argc, char *argv[])
74 struct unixctl_server *unixctl;
78 set_program_name(argv[0]);
81 parse_options(argc, argv);
86 ovs_fatal(0, "need at least one non-option argument; "
87 "use --help for usage");
90 ifaces = xmalloc(argc * sizeof *ifaces);
92 for (i = 0; i < argc; i++) {
93 if (iface_init(&ifaces[n_ifaces], argv[i])) {
98 ovs_fatal(0, "failed to initialize any DHCP clients");
101 for (i = 0; i < n_ifaces; i++) {
102 struct iface *iface = &ifaces[i];
103 dhclient_init(iface->dhcp, 0);
105 fatal_signal_add_hook(release_ifaces, NULL, true);
107 retval = regcomp(&accept_controller_regex, accept_controller_re,
108 REG_NOSUB | REG_EXTENDED);
110 size_t length = regerror(retval, &accept_controller_regex, NULL, 0);
111 char *buffer = xmalloc(length);
112 regerror(retval, &accept_controller_regex, buffer, length);
113 ovs_fatal(0, "%s: %s", accept_controller_re, buffer);
116 retval = unixctl_server_create(NULL, &unixctl);
118 ovs_fatal(retval, "Could not listen for unixctl connections");
121 die_if_already_running();
123 signal(SIGPIPE, SIG_IGN);
125 fatal_signal_block();
126 for (i = 0; i < n_ifaces; i++) {
127 struct iface *iface = &ifaces[i];
128 dhclient_run(iface->dhcp);
129 if (dhclient_changed(iface->dhcp)) {
130 bool is_bound = dhclient_is_bound(iface->dhcp);
133 /* Configure network device. */
134 if (!exit_without_bind) {
135 dhclient_configure_netdev(iface->dhcp);
136 dhclient_update_resolv_conf(iface->dhcp);
140 static bool detached = false;
143 /* Disable timeout, since discovery was successful. */
146 /* Print discovered parameters. */
148 dhcp_msg_to_string(dhclient_get_config(iface->dhcp),
150 fputs(ds_cstr(&ds), stdout);
155 /* Exit if the user requested it. */
156 if (exit_without_bind) {
157 VLOG_DBG("exiting because of successful binding on %s "
158 "and --exit-without-bind specified",
162 if (exit_after_bind) {
163 VLOG_DBG("exiting because of successful binding on %s "
164 "and --exit-after-bind specified",
169 /* Detach into background, if we haven't already. */
176 /* We only want an address on a single one of our interfaces.
177 * So: if we have an address on this interface, stop looking
178 * for one on the others; if we don't have an address on this
179 * interface, start looking everywhere. */
180 for (j = 0; j < n_ifaces; j++) {
181 struct iface *if2 = &ifaces[j];
184 dhclient_release(if2->dhcp);
186 dhclient_init(if2->dhcp, 0);
192 unixctl_server_run(unixctl);
193 for (i = 0; i < n_ifaces; i++) {
194 struct iface *iface = &ifaces[i];
195 dhclient_wait(iface->dhcp);
197 unixctl_server_wait(unixctl);
198 fatal_signal_unblock();
206 iface_init(struct iface *iface, const char *netdev_name)
210 iface->name = netdev_name;
213 if (exit_after_bind) {
214 /* Bring this interface up permanently, so that the bound address
215 * persists past program termination. */
216 struct netdev *netdev;
218 retval = netdev_open(iface->name, NETDEV_ETH_TYPE_NONE, &netdev);
220 ovs_error(retval, "Could not open %s device", iface->name);
223 retval = netdev_turn_flags_on(netdev, NETDEV_UP, true);
225 ovs_error(retval, "Could not bring %s device up", iface->name);
228 netdev_close(netdev);
231 retval = dhclient_create(iface->name, modify_dhcp_request,
232 validate_dhcp_offer, NULL, &iface->dhcp);
234 ovs_error(retval, "%s: failed to initialize DHCP client", iface->name);
242 release_ifaces(void *aux UNUSED)
246 for (i = 0; i < n_ifaces; i++) {
247 struct dhclient *dhcp = ifaces[i].dhcp;
248 dhclient_release(dhcp);
249 if (dhclient_changed(dhcp)) {
250 dhclient_configure_netdev(dhcp);
256 modify_dhcp_request(struct dhcp_msg *msg, void *aux UNUSED)
258 dhcp_msg_put_string(msg, DHCP_CODE_VENDOR_CLASS, "OpenFlow");
262 validate_dhcp_offer(const struct dhcp_msg *msg, void *aux UNUSED)
264 static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(60, 60);
268 vconn_name = dhcp_msg_get_string(msg, DHCP_CODE_OFP_CONTROLLER_VCONN);
270 VLOG_WARN_RL(&rl, "rejecting DHCP offer missing controller vconn");
273 accept = !regexec(&accept_controller_regex, vconn_name, 0, NULL, 0);
279 parse_options(int argc, char *argv[])
282 OPT_ACCEPT_VCONN = UCHAR_MAX + 1,
283 OPT_EXIT_WITHOUT_BIND,
287 static struct option long_options[] = {
288 {"accept-vconn", required_argument, 0, OPT_ACCEPT_VCONN},
289 {"exit-without-bind", no_argument, 0, OPT_EXIT_WITHOUT_BIND},
290 {"exit-after-bind", no_argument, 0, OPT_EXIT_AFTER_BIND},
291 {"no-detach", no_argument, 0, OPT_NO_DETACH},
292 {"timeout", required_argument, 0, 't'},
293 {"pidfile", optional_argument, 0, 'P'},
294 {"force", no_argument, 0, 'f'},
295 {"verbose", optional_argument, 0, 'v'},
296 {"help", no_argument, 0, 'h'},
297 {"version", no_argument, 0, 'V'},
300 char *short_options = long_options_to_short_options(long_options);
301 bool detach_after_bind = true;
304 unsigned long int timeout;
307 c = getopt_long(argc, argv, short_options, long_options, NULL);
313 case OPT_ACCEPT_VCONN:
314 accept_controller_re = (optarg[0] == '^'
316 : xasprintf("^%s", optarg));
319 case OPT_EXIT_WITHOUT_BIND:
320 exit_without_bind = true;
323 case OPT_EXIT_AFTER_BIND:
324 exit_after_bind = true;
328 detach_after_bind = false;
336 ignore_existing_pidfile();
340 timeout = strtoul(optarg, NULL, 10);
342 ovs_fatal(0, "value %s on -t or --timeout is not at least 1",
347 signal(SIGALRM, SIG_DFL);
354 OVS_PRINT_VERSION(0, 0);
358 vlog_set_verbosity(optarg);
370 if ((exit_without_bind + exit_after_bind + !detach_after_bind) > 1) {
371 ovs_fatal(0, "--exit-without-bind, --exit-after-bind, and --no-detach "
372 "are mutually exclusive");
374 if (detach_after_bind) {
382 printf("%s: a tool for discovering OpenFlow controllers.\n"
383 "usage: %s [OPTIONS] NETDEV [NETDEV...]\n"
384 "where each NETDEV is a network device on which to perform\n"
385 "controller discovery.\n"
386 "\nOrdinarily, ovs-discover runs in the foreground until it\n"
387 "obtains an IP address and discovers an OpenFlow controller via\n"
388 "DHCP, then it prints information about the controller to stdout\n"
389 "and detaches to the background to maintain the IP address lease.\n"
390 "\nNetworking options:\n"
391 " --accept-vconn=REGEX accept matching discovered controllers\n"
392 " --exit-without-bind exit after discovery, without binding\n"
393 " --exit-after-bind exit after discovery, after binding\n"
394 " --no-detach do not detach after discovery\n",
395 program_name, program_name);
397 printf("\nOther options:\n"
398 " -t, --timeout=SECS give up discovery after SECS seconds\n"
399 " -P, --pidfile[=FILE] create pidfile (default: %s/%s.pid)\n"
400 " -f, --force with -P, start even if already running\n"
401 " -h, --help display this help message\n"
402 " -V, --version display version information\n",
403 ovs_rundir, program_name);