1 /* Copyright (c) 2008 The Board of Trustees of The Leland Stanford
4 * We are making the OpenFlow specification and associated documentation
5 * (Software) available for public use and benefit with the expectation
6 * that others will use, modify and enhance the Software and contribute
7 * those enhancements back to the community. However, since we would
8 * like to make the Software available for broadest use, with as few
9 * restrictions as possible permission is hereby granted, free of
10 * charge, to any person obtaining a copy of this Software to deal in
11 * the Software under the copyrights without restriction, including
12 * without limitation the rights to use, copy, modify, merge, publish,
13 * distribute, sublicense, and/or sell copies of the Software, and to
14 * permit persons to whom the Software is furnished to do so, subject to
15 * the following conditions:
17 * The above copyright notice and this permission notice shall be
18 * included in all copies or substantial portions of the Software.
20 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
21 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
22 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
23 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
24 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
25 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
26 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
29 * The name and trademarks of copyright holder(s) may NOT be used in
30 * advertising or publicity pertaining to the Software or any
31 * derivatives without specific, written prior permission.
39 #include <netinet/in.h>
48 #include "command-line.h"
52 #include "dhcp-client.h"
53 #include "dynamic-string.h"
56 #include "learning-switch.h"
58 #include "mac-learning.h"
62 #include "poll-loop.h"
65 #include "vconn-ssl.h"
67 #include "vlog-socket.h"
70 #define THIS_MODULE VLM_secchan
72 /* Behavior when the connection to the controller fails. */
74 FAIL_OPEN, /* Act as learning switch. */
75 FAIL_CLOSED /* Drop all packets. */
78 /* Settings that may be configured by the user. */
80 /* Overall mode of operation. */
81 bool discovery; /* Discover the controller automatically? */
82 bool in_band; /* Connect to controller in-band? */
84 /* Related vconns and network devices. */
85 const char *nl_name; /* Local datapath (must be "nl:" vconn). */
86 char *of_name; /* ofX network device name. */
87 const char *controller_name; /* Controller (if not discovery mode). */
88 const char *listen_vconn_name; /* Listens for mgmt connections. */
90 /* Failure behavior. */
91 enum fail_mode fail_mode; /* Act as learning switch if no controller? */
92 int max_idle; /* Idle time for flows in fail-open mode. */
93 int probe_interval; /* # seconds idle before sending echo request. */
94 int max_backoff; /* Max # seconds between connection attempts. */
96 /* Discovery behavior. */
97 regex_t accept_controller_regex; /* Controller vconns to accept. */
98 const char *accept_controller_re; /* String version of regex. */
99 bool update_resolv_conf; /* Update /etc/resolv.conf? */
104 struct buffer *rxbuf;
111 #define HALF_REMOTE 1
112 struct half halves[2];
118 bool (*packet_cb)(struct relay *, int half, void *aux);
119 void (*periodic_cb)(void *aux);
123 static void parse_options(int argc, char *argv[], struct settings *);
124 static void usage(void) NO_RETURN;
126 static struct relay *relay_create(struct rconn *local, struct rconn *remote,
128 static struct relay *relay_accept(const struct settings *, struct vconn *);
129 static void relay_run(struct relay *, const struct hook[], size_t n_hooks);
130 static void relay_wait(struct relay *);
131 static void relay_destroy(struct relay *);
133 static struct hook make_hook(bool (*packet_cb)(struct relay *, int, void *),
134 void (*periodic_cb)(void *),
137 static struct discovery *discovery_init(const struct settings *);
138 static void discovery_question_connectivity(struct discovery *);
139 static bool discovery_run(struct discovery *, char **controller_name);
140 static void discovery_wait(struct discovery *);
142 static struct hook in_band_hook_create(const struct settings *);
143 static struct hook fail_open_hook_create(const struct settings *,
145 struct rconn *remote);
147 static void modify_dhcp_request(struct dhcp_msg *, void *aux);
148 static bool validate_dhcp_offer(const struct dhcp_msg *, void *aux);
151 main(int argc, char *argv[])
155 struct list relays = LIST_INITIALIZER(&relays);
157 struct hook hooks[3];
160 struct rconn *local_rconn, *remote_rconn;
161 struct vconn *listen_vconn;
162 struct relay *controller_relay;
163 struct discovery *discovery;
166 set_program_name(argv[0]);
167 register_fault_handlers();
169 parse_options(argc, argv, &s);
171 /* Start listening for management connections. */
172 if (s.listen_vconn_name) {
173 retval = vconn_open(s.listen_vconn_name, &listen_vconn);
174 if (retval && retval != EAGAIN) {
175 fatal(retval, "opening %s", s.listen_vconn_name);
177 if (!vconn_is_passive(listen_vconn)) {
178 fatal(0, "%s is not a passive vconn", s.listen_vconn_name);
184 /* Start controller discovery. */
185 discovery = s.discovery ? discovery_init(&s) : NULL;
187 /* Start listening for vlogconf requests. */
188 retval = vlog_server_listen(NULL, NULL);
190 fatal(retval, "Could not listen for vlog connections");
195 /* Connect to datapath. */
196 local_rconn = rconn_create(1, 0, s.max_backoff);
197 rconn_connect(local_rconn, s.nl_name);
199 /* Connect to controller. */
200 remote_rconn = rconn_create(1, s.probe_interval, s.max_backoff);
201 if (s.controller_name) {
202 retval = rconn_connect(remote_rconn, s.controller_name);
203 if (retval == EAFNOSUPPORT) {
204 fatal(0, "No support for %s vconn", s.controller_name);
208 /* Start relaying. */
209 controller_relay = relay_create(local_rconn, remote_rconn, false);
210 list_push_back(&relays, &controller_relay->node);
215 hooks[n_hooks++] = in_band_hook_create(&s);
217 if (s.fail_mode == FAIL_OPEN) {
218 hooks[n_hooks++] = fail_open_hook_create(&s,
219 local_rconn, remote_rconn);
221 assert(n_hooks <= ARRAY_SIZE(hooks));
228 LIST_FOR_EACH_SAFE (r, n, struct relay, node, &relays) {
229 relay_run(r, hooks, n_hooks);
233 struct relay *r = relay_accept(&s, listen_vconn);
237 list_push_back(&relays, &r->node);
240 for (i = 0; i < n_hooks; i++) {
241 if (hooks[i].periodic_cb) {
242 hooks[i].periodic_cb(hooks[i].aux);
246 char *controller_name;
247 if (rconn_is_connectivity_questionable(remote_rconn)) {
248 discovery_question_connectivity(discovery);
250 if (discovery_run(discovery, &controller_name)) {
251 if (controller_name) {
252 rconn_connect(remote_rconn, controller_name);
254 rconn_disconnect(remote_rconn);
259 /* Wait for something to happen. */
260 LIST_FOR_EACH (r, struct relay, node, &relays) {
264 vconn_accept_wait(listen_vconn);
267 discovery_wait(discovery);
276 make_hook(bool (*packet_cb)(struct relay *, int half, void *aux),
277 void (*periodic_cb)(void *aux),
281 h.packet_cb = packet_cb;
282 h.periodic_cb = periodic_cb;
287 /* OpenFlow message relaying. */
289 static struct relay *
290 relay_accept(const struct settings *s, struct vconn *listen_vconn)
292 struct vconn *new_remote, *new_local;
293 char *nl_name_without_subscription;
294 struct rconn *r1, *r2;
297 retval = vconn_accept(listen_vconn, &new_remote);
299 if (retval != EAGAIN) {
300 VLOG_WARN("accept failed (%s)", strerror(retval));
305 /* nl:123 or nl:123:1 opens a netlink connection to local datapath 123. We
306 * only accept the former syntax in main().
308 * nl:123:0 opens a netlink connection to local datapath 123 without
309 * obtaining a subscription for ofp_packet_in or ofp_flow_expired
311 nl_name_without_subscription = xasprintf("%s:0", s->nl_name);
312 retval = vconn_open(nl_name_without_subscription, &new_local);
314 VLOG_ERR("could not connect to %s (%s)",
315 nl_name_without_subscription, strerror(retval));
316 vconn_close(new_remote);
317 free(nl_name_without_subscription);
321 /* Create and return relay. */
322 r1 = rconn_create(1, 0, 0);
323 rconn_connect_unreliably(r1, nl_name_without_subscription, new_local);
324 free(nl_name_without_subscription);
326 r2 = rconn_create(1, 0, 0);
327 rconn_connect_unreliably(r2, "passive", new_remote);
329 return relay_create(r1, r2, true);
332 static struct relay *
333 relay_create(struct rconn *local, struct rconn *remote, bool is_mgmt_conn)
338 r = xmalloc(sizeof *r);
339 r->halves[HALF_LOCAL].rconn = local;
340 r->halves[HALF_REMOTE].rconn = remote;
341 for (i = 0; i < 2; i++) {
342 r->halves[i].rxbuf = NULL;
344 r->is_mgmt_conn = is_mgmt_conn;
349 relay_run(struct relay *r, const struct hook hooks[], size_t n_hooks)
354 for (i = 0; i < 2; i++) {
355 rconn_run(r->halves[i].rconn);
358 /* Limit the number of iterations to prevent other tasks from starving. */
359 for (iteration = 0; iteration < 50; iteration++) {
360 bool progress = false;
361 for (i = 0; i < 2; i++) {
362 struct half *this = &r->halves[i];
363 struct half *peer = &r->halves[!i];
366 this->rxbuf = rconn_recv(this->rconn);
368 const struct hook *h;
369 for (h = hooks; h < &hooks[n_hooks]; h++) {
370 if (h->packet_cb(r, i, h->aux)) {
371 buffer_delete(this->rxbuf);
381 int retval = rconn_send(peer->rconn, this->rxbuf);
382 if (retval != EAGAIN) {
386 buffer_delete(this->rxbuf);
397 if (r->is_mgmt_conn) {
398 for (i = 0; i < 2; i++) {
399 struct half *this = &r->halves[i];
400 if (!rconn_is_alive(this->rconn)) {
409 relay_wait(struct relay *r)
413 for (i = 0; i < 2; i++) {
414 struct half *this = &r->halves[i];
416 rconn_run_wait(this->rconn);
418 rconn_recv_wait(this->rconn);
424 relay_destroy(struct relay *r)
428 list_remove(&r->node);
429 for (i = 0; i < 2; i++) {
430 struct half *this = &r->halves[i];
431 rconn_destroy(this->rconn);
432 buffer_delete(this->rxbuf);
437 /* In-band control. */
439 struct in_band_data {
440 const struct settings *s;
441 struct mac_learning *ml;
442 struct netdev *of_device;
443 uint8_t mac[ETH_ADDR_LEN];
447 queue_tx(struct rconn *rc, struct buffer *b)
449 if (rconn_force_send(rc, b)) {
455 is_controller_mac(const uint8_t dl_addr[ETH_ADDR_LEN], struct netdev *netdev,
456 struct rconn *controller)
458 static uint32_t ip, last_nonzero_ip;
459 static uint8_t mac[ETH_ADDR_LEN], last_nonzero_mac[ETH_ADDR_LEN];
460 static time_t next_refresh = 0;
462 uint32_t last_ip = ip;
464 time_t now = time(0);
466 ip = rconn_get_ip(controller);
467 if (last_ip != ip || !next_refresh || now >= next_refresh) {
470 /* Look up MAC address. */
471 memset(mac, 0, sizeof mac);
473 int retval = netdev_arp_lookup(netdev, ip, mac);
475 VLOG_DBG("cannot look up controller hw address ("IP_FMT"): %s",
476 IP_ARGS(&ip), strerror(retval));
479 have_mac = !eth_addr_is_zero(mac);
481 /* Log changes in IP, MAC addresses. */
482 if (ip && ip != last_nonzero_ip) {
483 VLOG_DBG("controller IP address changed from "IP_FMT
484 " to "IP_FMT, IP_ARGS(&last_nonzero_ip), IP_ARGS(&ip));
485 last_nonzero_ip = ip;
487 if (have_mac && memcmp(last_nonzero_mac, mac, ETH_ADDR_LEN)) {
488 VLOG_DBG("controller MAC address changed from "ETH_ADDR_FMT" to "
490 ETH_ADDR_ARGS(last_nonzero_mac), ETH_ADDR_ARGS(mac));
491 memcpy(last_nonzero_mac, mac, ETH_ADDR_LEN);
494 /* Schedule next refresh.
496 * If we have an IP address but not a MAC address, then refresh
497 * quickly, since we probably will get a MAC address soon (via ARP).
498 * Otherwise, we can afford to wait a little while. */
499 next_refresh = now + (!ip || have_mac ? 10 : 1);
501 return !eth_addr_is_zero(mac) && eth_addr_equals(mac, dl_addr);
505 in_band_packet_cb(struct relay *r, int half, void *in_band_)
507 struct in_band_data *in_band = in_band_;
508 struct rconn *rc = r->halves[HALF_LOCAL].rconn;
509 struct buffer *msg = r->halves[HALF_LOCAL].rxbuf;
510 struct ofp_packet_in *opi;
511 struct ofp_header *oh;
512 size_t pkt_ofs, pkt_len;
515 uint16_t in_port, out_port;
517 if (half != HALF_LOCAL || r->is_mgmt_conn) {
522 if (oh->type != OFPT_PACKET_IN) {
525 if (msg->size < offsetof (struct ofp_packet_in, data)) {
526 VLOG_WARN("packet too short (%zu bytes) for packet_in", msg->size);
530 /* Extract flow data from 'opi' into 'flow'. */
532 in_port = ntohs(opi->in_port);
533 pkt_ofs = offsetof(struct ofp_packet_in, data);
534 pkt_len = ntohs(opi->header.length) - pkt_ofs;
535 pkt.data = opi->data;
537 flow_extract(&pkt, in_port, &flow);
539 /* Deal with local stuff. */
540 if (in_port == OFPP_LOCAL) {
541 out_port = mac_learning_lookup(in_band->ml, flow.dl_dst);
542 } else if (eth_addr_equals(flow.dl_dst, in_band->mac)) {
543 out_port = OFPP_LOCAL;
544 if (mac_learning_learn(in_band->ml, flow.dl_src, in_port)) {
545 VLOG_DBG("learned that "ETH_ADDR_FMT" is on port %"PRIu16,
546 ETH_ADDR_ARGS(flow.dl_src), in_port);
548 } else if (flow.dl_type == htons(ETH_TYPE_ARP)
549 && eth_addr_is_broadcast(flow.dl_dst)
550 && is_controller_mac(flow.dl_src, in_band->of_device,
551 r->halves[HALF_REMOTE].rconn)) {
552 out_port = OFPP_FLOOD;
557 if (out_port != OFPP_FLOOD) {
558 /* The output port is known, so add a new flow. */
559 queue_tx(rc, make_add_simple_flow(&flow, ntohl(opi->buffer_id),
560 out_port, in_band->s->max_idle));
562 /* If the switch didn't buffer the packet, we need to send a copy. */
563 if (ntohl(opi->buffer_id) == UINT32_MAX) {
564 queue_tx(rc, make_unbuffered_packet_out(&pkt, in_port, out_port));
567 /* We don't know that MAC. Send along the packet without setting up a
570 if (ntohl(opi->buffer_id) == UINT32_MAX) {
571 b = make_unbuffered_packet_out(&pkt, in_port, out_port);
573 b = make_buffered_packet_out(ntohl(opi->buffer_id),
582 in_band_hook_create(const struct settings *s)
584 struct in_band_data *in_band;
587 in_band = xmalloc(sizeof *in_band);
589 in_band->ml = mac_learning_create();
590 retval = netdev_open(s->of_name, NETDEV_ETH_TYPE_NONE,
591 &in_band->of_device);
593 fatal(retval, "Could not open %s device", s->of_name);
595 memcpy(in_band->mac, netdev_get_etheraddr(in_band->of_device),
598 return make_hook(in_band_packet_cb, NULL, in_band);
601 /* Fail open support. */
603 struct fail_open_data {
604 const struct settings *s;
605 struct rconn *local_rconn;
606 struct rconn *remote_rconn;
607 struct lswitch *lswitch;
608 int last_disconn_secs;
611 /* Causes 'r' to enter or leave fail-open mode, if appropriate. */
613 fail_open_periodic_cb(void *fail_open_)
615 struct fail_open_data *fail_open = fail_open_;
619 disconn_secs = rconn_disconnected_duration(fail_open->remote_rconn);
620 open = disconn_secs >= fail_open->s->probe_interval * 3;
621 if (open != (fail_open->lswitch != NULL)) {
623 VLOG_WARN("No longer in fail-open mode");
624 lswitch_destroy(fail_open->lswitch);
625 fail_open->lswitch = NULL;
627 VLOG_WARN("Could not connect to controller for %d seconds, "
628 "failing open", disconn_secs);
629 fail_open->lswitch = lswitch_create(fail_open->local_rconn, true,
630 fail_open->s->max_idle);
631 fail_open->last_disconn_secs = disconn_secs;
633 } else if (open && disconn_secs > fail_open->last_disconn_secs + 60) {
634 VLOG_WARN("Still in fail-open mode after %d seconds disconnected "
635 "from controller", disconn_secs);
636 fail_open->last_disconn_secs = disconn_secs;
641 fail_open_packet_cb(struct relay *r, int half, void *fail_open_)
643 struct fail_open_data *fail_open = fail_open_;
644 if (half != HALF_LOCAL || r->is_mgmt_conn || !fail_open->lswitch) {
647 lswitch_process_packet(fail_open->lswitch, fail_open->local_rconn,
648 r->halves[HALF_LOCAL].rxbuf);
649 rconn_run(fail_open->local_rconn);
655 fail_open_hook_create(const struct settings *s, struct rconn *local_rconn,
656 struct rconn *remote_rconn)
658 struct fail_open_data *fail_open = xmalloc(sizeof *fail_open);
660 fail_open->local_rconn = local_rconn;
661 fail_open->remote_rconn = remote_rconn;
662 fail_open->lswitch = NULL;
663 return make_hook(fail_open_packet_cb, fail_open_periodic_cb, fail_open);
666 /* Controller discovery. */
670 const struct settings *s;
671 struct dhclient *dhcp;
672 bool ever_successful;
675 static struct discovery *
676 discovery_init(const struct settings *s)
678 struct netdev *netdev;
680 struct dhclient *dhcp;
683 /* Bring ofX network device up. */
684 retval = netdev_open(s->of_name, NETDEV_ETH_TYPE_NONE, &netdev);
686 fatal(retval, "Could not open %s device", s->of_name);
688 retval = netdev_turn_flags_on(netdev, NETDEV_UP, true);
690 fatal(retval, "Could not bring %s device up", s->of_name);
692 netdev_close(netdev);
694 /* Initialize DHCP client. */
695 retval = dhclient_create(s->of_name, modify_dhcp_request,
696 validate_dhcp_offer, (void *) s, &dhcp);
698 fatal(retval, "Failed to initialize DHCP client");
700 dhclient_init(dhcp, 0);
702 d = xmalloc(sizeof *d);
705 d->ever_successful = false;
710 discovery_question_connectivity(struct discovery *d)
712 dhclient_force_renew(d->dhcp, 15);
716 discovery_run(struct discovery *d, char **controller_name)
718 dhclient_run(d->dhcp);
719 if (!dhclient_changed(d->dhcp)) {
723 dhclient_configure_netdev(d->dhcp);
724 if (d->s->update_resolv_conf) {
725 dhclient_update_resolv_conf(d->dhcp);
728 if (dhclient_is_bound(d->dhcp)) {
729 *controller_name = dhcp_msg_get_string(dhclient_get_config(d->dhcp),
730 DHCP_CODE_OFP_CONTROLLER_VCONN);
731 VLOG_WARN("%s: discovered controller", *controller_name);
732 d->ever_successful = true;
733 } else if (controller_name) {
734 *controller_name = NULL;
735 if (d->ever_successful) {
736 VLOG_WARN("discovered controller no longer available");
743 discovery_wait(struct discovery *d)
745 dhclient_wait(d->dhcp);
749 modify_dhcp_request(struct dhcp_msg *msg, void *aux)
751 dhcp_msg_put_string(msg, DHCP_CODE_VENDOR_CLASS, "OpenFlow");
755 validate_dhcp_offer(const struct dhcp_msg *msg, void *s_)
757 const struct settings *s = s_;
761 vconn_name = dhcp_msg_get_string(msg, DHCP_CODE_OFP_CONTROLLER_VCONN);
763 VLOG_WARN("rejecting DHCP offer missing controller vconn");
766 accept = !regexec(&s->accept_controller_regex, vconn_name, 0, NULL, 0);
768 VLOG_WARN("rejecting controller vconn that fails to match %s",
769 s->accept_controller_re);
775 /* User interface. */
778 parse_options(int argc, char *argv[], struct settings *s)
781 OPT_ACCEPT_VCONN = UCHAR_MAX + 1,
783 OPT_INACTIVITY_PROBE,
787 static struct option long_options[] = {
788 {"accept-vconn", required_argument, 0, OPT_ACCEPT_VCONN},
789 {"no-resolv-conf", no_argument, 0, OPT_NO_RESOLV_CONF},
790 {"fail", required_argument, 0, 'f'},
791 {"inactivity-probe", required_argument, 0, OPT_INACTIVITY_PROBE},
792 {"max-idle", required_argument, 0, OPT_MAX_IDLE},
793 {"max-backoff", required_argument, 0, OPT_MAX_BACKOFF},
794 {"listen", required_argument, 0, 'l'},
795 {"detach", no_argument, 0, 'D'},
796 {"pidfile", optional_argument, 0, 'P'},
797 {"verbose", optional_argument, 0, 'v'},
798 {"help", no_argument, 0, 'h'},
799 {"version", no_argument, 0, 'V'},
800 VCONN_SSL_LONG_OPTIONS
803 char *short_options = long_options_to_short_options(long_options);
804 char *accept_re = NULL;
807 /* Set defaults that we can figure out before parsing options. */
808 s->listen_vconn_name = NULL;
809 s->fail_mode = FAIL_OPEN;
811 s->probe_interval = 15;
813 s->update_resolv_conf = true;
817 c = getopt_long(argc, argv, short_options, long_options, NULL);
823 case OPT_ACCEPT_VCONN:
824 accept_re = optarg[0] == '^' ? optarg : xasprintf("^%s", optarg);
827 case OPT_NO_RESOLV_CONF:
828 s->update_resolv_conf = false;
832 if (!strcmp(optarg, "open")) {
833 s->fail_mode = FAIL_OPEN;
834 } else if (!strcmp(optarg, "closed")) {
835 s->fail_mode = FAIL_CLOSED;
838 "-f or --fail argument must be \"open\" or \"closed\"");
842 case OPT_INACTIVITY_PROBE:
843 s->probe_interval = atoi(optarg);
844 if (s->probe_interval < 5) {
845 fatal(0, "--inactivity-probe argument must be at least 5");
850 if (!strcmp(optarg, "permanent")) {
851 s->max_idle = OFP_FLOW_PERMANENT;
853 s->max_idle = atoi(optarg);
854 if (s->max_idle < 1 || s->max_idle > 65535) {
855 fatal(0, "--max-idle argument must be between 1 and "
856 "65535 or the word 'permanent'");
861 case OPT_MAX_BACKOFF:
862 s->max_backoff = atoi(optarg);
863 if (s->max_backoff < 1) {
864 fatal(0, "--max-backoff argument must be at least 1");
865 } else if (s->max_backoff > 3600) {
866 s->max_backoff = 3600;
879 if (s->listen_vconn_name) {
880 fatal(0, "-l or --listen may be only specified once");
882 s->listen_vconn_name = optarg;
889 printf("%s "VERSION" compiled "__DATE__" "__TIME__"\n", argv[0]);
893 vlog_set_verbosity(optarg);
896 VCONN_SSL_OPTION_HANDLERS
909 if (argc < 1 || argc > 2) {
910 fatal(0, "need one or two non-option arguments; use --help for usage");
913 /* Local and remote vconns. */
914 s->nl_name = argv[0];
915 if (strncmp(s->nl_name, "nl:", 3)
916 || strlen(s->nl_name) < 4
917 || s->nl_name[strspn(s->nl_name + 3, "0123456789") + 3]) {
918 fatal(0, "%s: argument is not of the form \"nl:DP_IDX\"", s->nl_name);
920 s->of_name = xasprintf("of%s", s->nl_name + 3);
921 s->controller_name = argc > 1 ? xstrdup(argv[1]) : NULL;
923 /* Set accept_controller_regex. */
925 accept_re = vconn_ssl_is_configured() ? "^ssl:.*" : ".*";
927 retval = regcomp(&s->accept_controller_regex, accept_re,
928 REG_NOSUB | REG_EXTENDED);
930 size_t length = regerror(retval, &s->accept_controller_regex, NULL, 0);
931 char *buffer = xmalloc(length);
932 regerror(retval, &s->accept_controller_regex, buffer, length);
933 fatal(0, "%s: %s", accept_re, buffer);
935 s->accept_controller_re = accept_re;
937 /* Mode of operation. */
938 s->discovery = s->controller_name == NULL;
942 enum netdev_flags flags;
943 struct netdev *netdev;
945 retval = netdev_open(s->of_name, NETDEV_ETH_TYPE_NONE, &netdev);
947 fatal(retval, "Could not open %s device", s->of_name);
950 retval = netdev_get_flags(netdev, &flags);
952 fatal(retval, "Could not get flags for %s device", s->of_name);
955 s->in_band = (flags & NETDEV_UP) != 0;
956 if (s->in_band && netdev_get_in6(netdev, NULL)) {
957 VLOG_WARN("Ignoring IPv6 address on %s device: IPv6 not supported",
961 netdev_close(netdev);
968 printf("%s: secure channel, a relay for OpenFlow messages.\n"
969 "usage: %s [OPTIONS] nl:DP_IDX [CONTROLLER]\n"
970 "where nl:DP_IDX is a datapath that has been added with dpctl.\n"
971 "CONTROLLER is an active OpenFlow connection method; if it is\n"
972 "omitted, then secchan performs controller discovery.\n",
973 program_name, program_name);
974 vconn_usage(true, true);
975 printf("\nController discovery options:\n"
976 " --accept-vconn=REGEX accept matching discovered controllers\n"
977 " --no-resolv-conf do not update /etc/resolv.conf\n"
978 "\nNetworking options:\n"
979 " -f, --fail=open|closed when controller connection fails:\n"
980 " closed: drop all packets\n"
981 " open (default): act as learning switch\n"
982 " --inactivity-probe=SECS time between inactivity probes\n"
983 " --max-idle=SECS max idle for flows set up by secchan\n"
984 " --max-backoff=SECS max time between controller connection\n"
985 " attempts (default: 15 seconds)\n"
986 " -l, --listen=METHOD allow management connections on METHOD\n"
987 " (a passive OpenFlow connection method)\n"
989 " -D, --detach run in background as daemon\n"
990 " -P, --pidfile[=FILE] create pidfile (default: %s/secchan.pid)\n"
991 " -v, --verbose=MODULE[:FACILITY[:LEVEL]] set logging levels\n"
992 " -v, --verbose set maximum verbosity level\n"
993 " -h, --help display this help message\n"
994 " -V, --version display version information\n",