1 /* Copyright (c) 2013 Nicira, Inc.
3 * Licensed under the Apache License, Version 2.0 (the "License");
4 * you may not use this file except in compliance with the License.
5 * You may obtain a copy of the License at:
7 * http://www.apache.org/licenses/LICENSE-2.0
9 * Unless required by applicable law or agreed to in writing, software
10 * distributed under the License is distributed on an "AS IS" BASIS,
11 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 * See the License for the specific language governing permissions and
13 * limitations under the License. */
18 #include <arpa/inet.h>
22 #include "dynamic-string.h"
30 #include "openvswitch/types.h"
32 #include "poll-loop.h"
40 VLOG_DEFINE_THIS_MODULE(bfd);
44 * The goal of this module is to replace CFM with something both more flexible
45 * and standards compliant. In service of this goal, the following needs to be
49 * * Implement Demand mode.
50 * * Go through the RFC line by line and verify we comply.
51 * * Test against a hardware implementation. Preferably a popular one.
52 * * Delete BFD packets with nw_ttl != 255 in the datapath to prevent DOS
57 * - BFD show into ovs-bugtool.
59 * - Set TOS/PCP on inner BFD frame, and outer tunnel header when encapped.
61 * - CFM "check_tnl_key" option equivalent.
63 * - CFM "fault override" equivalent.
65 * - Sending BFD messages should be in its own thread/process.
67 * - Scale testing. How does it operate when there are large number of bfd
68 * sessions? Do we ever have random flaps? What's the CPU utilization?
70 * - Rely on data traffic for liveness by using BFD demand mode.
71 * If we're receiving traffic on a port, we can safely assume it's up (modulo
72 * unidrectional failures). BFD has a demand mode in which it can stay quiet
73 * unless it feels the need to check the status of the port. Using this, we
74 * can implement a strategy in which BFD only sends control messages on dark
77 * - Depending on how one interprets the spec, it appears that a BFD session
78 * can never change bfd.LocalDiag to "No Diagnostic". We should verify that
79 * this is what hardware implementations actually do. Seems like "No
80 * Diagnostic" should be set once a BFD session state goes UP. */
85 FLAG_MULTIPOINT = 1 << 0,
94 STATE_ADMIN_DOWN = 0 << 6,
101 DIAG_NONE = 0, /* No Diagnostic. */
102 DIAG_EXPIRED = 1, /* Control Detection Time Expired. */
103 DIAG_ECHO_FAILED = 2, /* Echo Function Failed. */
104 DIAG_RMT_DOWN = 3, /* Neighbor Signaled Session Down. */
105 DIAG_FWD_RESET = 4, /* Forwarding Plane Reset. */
106 DIAG_PATH_DOWN = 5, /* Path Down. */
107 DIAG_CPATH_DOWN = 6, /* Concatenated Path Down. */
108 DIAG_ADMIN_DOWN = 7, /* Administratively Down. */
109 DIAG_RCPATH_DOWN = 8 /* Reverse Concatenated Path Down. */
112 /* RFC 5880 Section 4.1
114 * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
115 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
116 * |Vers | Diag |Sta|P|F|C|A|D|M| Detect Mult | Length |
117 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
118 * | My Discriminator |
119 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
120 * | Your Discriminator |
121 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
122 * | Desired Min TX Interval |
123 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
124 * | Required Min RX Interval |
125 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
126 * | Required Min Echo RX Interval |
127 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ */
129 uint8_t vers_diag; /* Version and diagnostic. */
130 uint8_t flags; /* 2bit State field followed by flags. */
131 uint8_t mult; /* Fault detection multiplier. */
132 uint8_t length; /* Length of this BFD message. */
133 ovs_be32 my_disc; /* My discriminator. */
134 ovs_be32 your_disc; /* Your discriminator. */
135 ovs_be32 min_tx; /* Desired minimum tx interval. */
136 ovs_be32 min_rx; /* Required minimum rx interval. */
137 ovs_be32 min_rx_echo; /* Required minimum echo rx interval. */
139 BUILD_ASSERT_DECL(BFD_PACKET_LEN == sizeof(struct msg));
141 #define DIAG_MASK 0x1f
143 #define STATE_MASK 0xC0
144 #define FLAGS_MASK 0x3f
147 struct hmap_node node; /* In 'all_bfds'. */
148 uint32_t disc; /* bfd.LocalDiscr. Key in 'all_bfds' hmap. */
150 char *name; /* Name used for logging. */
152 bool cpath_down; /* Concatenated Path Down. */
153 uint8_t mult; /* bfd.DetectMult. */
155 enum state state; /* bfd.SessionState. */
156 enum state rmt_state; /* bfd.RemoteSessionState. */
158 enum diag diag; /* bfd.LocalDiag. */
159 enum diag rmt_diag; /* Remote diagnostic. */
161 enum flags flags; /* Flags sent on messages. */
162 enum flags rmt_flags; /* Flags last received. */
164 uint32_t rmt_disc; /* bfd.RemoteDiscr. */
166 uint16_t udp_src; /* UDP source port. */
168 /* All timers in milliseconds. */
169 long long int rmt_min_rx; /* bfd.RemoteMinRxInterval. */
170 long long int rmt_min_tx; /* Remote minimum TX interval. */
172 long long int cfg_min_tx; /* Configured minimum TX rate. */
173 long long int cfg_min_rx; /* Configured required minimum RX rate. */
174 long long int poll_min_tx; /* Min TX negotating in a poll sequence. */
175 long long int poll_min_rx; /* Min RX negotating in a poll sequence. */
176 long long int min_tx; /* bfd.DesiredMinTxInterval. */
177 long long int min_rx; /* bfd.RequiredMinRxInterval. */
179 long long int last_tx; /* Last TX time. */
180 long long int next_tx; /* Next TX time. */
181 long long int detect_time; /* RFC 5880 6.8.4 Detection time. */
184 static bool bfd_in_poll(const struct bfd *);
185 static void bfd_poll(struct bfd *bfd);
186 static const char *bfd_diag_str(enum diag);
187 static const char *bfd_state_str(enum state);
188 static long long int bfd_min_tx(const struct bfd *);
189 static long long int bfd_tx_interval(const struct bfd *);
190 static long long int bfd_rx_interval(const struct bfd *);
191 static void bfd_set_next_tx(struct bfd *);
192 static void bfd_set_state(struct bfd *, enum state, enum diag);
193 static uint32_t generate_discriminator(void);
194 static void bfd_put_details(struct ds *, const struct bfd *);
195 static void bfd_unixctl_show(struct unixctl_conn *, int argc,
196 const char *argv[], void *aux OVS_UNUSED);
197 static void log_msg(enum vlog_level, const struct msg *, const char *message,
200 static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(20, 20);
201 static struct hmap all_bfds = HMAP_INITIALIZER(&all_bfds);
203 /* Returns true if the interface on which 'bfd' is running may be used to
204 * forward traffic according to the BFD session state. */
206 bfd_forwarding(const struct bfd *bfd)
208 return bfd->state == STATE_UP
209 && bfd->rmt_diag != DIAG_PATH_DOWN
210 && bfd->rmt_diag != DIAG_CPATH_DOWN
211 && bfd->rmt_diag != DIAG_RCPATH_DOWN;
214 /* Returns a 'smap' of key value pairs representing the status of 'bfd'
215 * intended for the OVS database. */
217 bfd_get_status(const struct bfd *bfd, struct smap *smap)
219 smap_add(smap, "forwarding", bfd_forwarding(bfd) ? "true" : "false");
220 smap_add(smap, "state", bfd_state_str(bfd->state));
221 smap_add(smap, "diagnostic", bfd_diag_str(bfd->diag));
223 if (bfd->state != STATE_DOWN) {
224 smap_add(smap, "remote_state", bfd_state_str(bfd->rmt_state));
225 smap_add(smap, "remote_diagnostic", bfd_diag_str(bfd->rmt_diag));
229 /* Initializes, destroys, or reconfigures the BFD session 'bfd' (named 'name'),
230 * according to the database configuration contained in 'cfg'. Takes ownership
231 * of 'bfd', which may be NULL. Returns a BFD object which may be used as a
232 * handle for the session, or NULL if BFD is not enabled according to 'cfg'.
233 * Also returns NULL if cfg is NULL. */
235 bfd_configure(struct bfd *bfd, const char *name,
236 const struct smap *cfg)
238 static uint16_t udp_src = 0;
239 static bool init = false;
241 long long int min_tx, min_rx;
245 unixctl_command_register("bfd/show", "[interface]", 0, 1,
246 bfd_unixctl_show, NULL);
250 if (!cfg || !smap_get_bool(cfg, "enable", false)) {
252 hmap_remove(&all_bfds, &bfd->node);
260 bfd = xzalloc(sizeof *bfd);
261 bfd->name = xstrdup(name);
262 bfd->disc = generate_discriminator();
263 hmap_insert(&all_bfds, &bfd->node, bfd->disc);
265 bfd->diag = DIAG_NONE;
269 /* RFC 5881 section 4
270 * The source port MUST be in the range 49152 through 65535. The same
271 * UDP source port number MUST be used for all BFD Control packets
272 * associated with a particular session. The source port number SHOULD
273 * be unique among all BFD sessions on the system. */
274 bfd->udp_src = (udp_src++ % 16384) + 49152;
276 bfd_set_state(bfd, STATE_DOWN, DIAG_NONE);
279 min_tx = smap_get_int(cfg, "min_tx", 100);
280 min_tx = MAX(min_tx, 100);
281 if (bfd->cfg_min_tx != min_tx) {
282 bfd->cfg_min_tx = min_tx;
283 if (bfd->state != STATE_UP
284 || (!bfd_in_poll(bfd) && bfd->cfg_min_tx < bfd->min_tx)) {
285 bfd->min_tx = bfd->cfg_min_tx;
290 min_rx = smap_get_int(cfg, "min_rx", 1000);
291 min_rx = MAX(min_rx, 100);
292 if (bfd->cfg_min_rx != min_rx) {
293 bfd->cfg_min_rx = min_rx;
294 if (bfd->state != STATE_UP
295 || (!bfd_in_poll(bfd) && bfd->cfg_min_rx > bfd->min_rx)) {
296 bfd->min_rx = bfd->cfg_min_rx;
301 cpath_down = smap_get_bool(cfg, "cpath_down", false);
302 if (bfd->cpath_down != cpath_down) {
303 bfd->cpath_down = cpath_down;
304 if (bfd->diag == DIAG_NONE || bfd->diag == DIAG_CPATH_DOWN) {
305 bfd_set_state(bfd, bfd->state, DIAG_NONE);
313 bfd_wait(const struct bfd *bfd)
315 if (bfd->flags & FLAG_FINAL) {
316 poll_immediate_wake();
319 poll_timer_wait_until(bfd->next_tx);
320 if (bfd->state > STATE_DOWN) {
321 poll_timer_wait_until(bfd->detect_time);
326 bfd_run(struct bfd *bfd)
328 if (bfd->state > STATE_DOWN && time_msec() >= bfd->detect_time) {
329 bfd_set_state(bfd, STATE_DOWN, DIAG_EXPIRED);
332 if (bfd->min_tx != bfd->cfg_min_tx || bfd->min_rx != bfd->cfg_min_rx) {
338 bfd_should_send_packet(const struct bfd *bfd)
340 return bfd->flags & FLAG_FINAL || time_msec() >= bfd->next_tx;
344 bfd_put_packet(struct bfd *bfd, struct ofpbuf *p,
345 uint8_t eth_src[ETH_ADDR_LEN])
347 long long int min_tx, min_rx;
348 struct udp_header *udp;
349 struct eth_header *eth;
350 struct ip_header *ip;
354 long long int delay = time_msec() - bfd->next_tx;
355 long long int interval = bfd_tx_interval(bfd);
356 if (delay > interval * 3 / 2) {
357 VLOG_WARN("%s: long delay of %lldms (expected %lldms) sending BFD"
358 " control message", bfd->name, delay, interval);
362 /* RFC 5880 Section 6.5
363 * A BFD Control packet MUST NOT have both the Poll (P) and Final (F) bits
365 ovs_assert(!(bfd->flags & FLAG_POLL) || !(bfd->flags & FLAG_FINAL));
367 ofpbuf_reserve(p, 2); /* Properly align after the ethernet header. */
368 eth = ofpbuf_put_uninit(p, sizeof *eth);
369 memcpy(eth->eth_dst, eth_addr_broadcast, ETH_ADDR_LEN);
370 memcpy(eth->eth_src, eth_src, ETH_ADDR_LEN);
371 eth->eth_type = htons(ETH_TYPE_IP);
373 ip = ofpbuf_put_zeros(p, sizeof *ip);
374 ip->ip_ihl_ver = IP_IHL_VER(5, 4);
375 ip->ip_tot_len = htons(sizeof *ip + sizeof *udp + sizeof *msg);
377 ip->ip_proto = IPPROTO_UDP;
378 ip->ip_src = htonl(0xA9FE0100); /* 169.254.1.0 Link Local. */
379 ip->ip_dst = htonl(0xA9FE0101); /* 169.254.1.1 Link Local. */
380 ip->ip_csum = csum(ip, sizeof *ip);
382 udp = ofpbuf_put_zeros(p, sizeof *udp);
383 udp->udp_src = htons(bfd->udp_src);
384 udp->udp_dst = htons(BFD_DEST_PORT);
385 udp->udp_len = htons(sizeof *udp + sizeof *msg);
387 msg = ofpbuf_put_uninit(p, sizeof *msg);
388 msg->vers_diag = (BFD_VERSION << 5) | bfd->diag;
389 msg->flags = (bfd->state & STATE_MASK) | bfd->flags;
391 msg->mult = bfd->mult;
392 msg->length = BFD_PACKET_LEN;
393 msg->my_disc = htonl(bfd->disc);
394 msg->your_disc = htonl(bfd->rmt_disc);
395 msg->min_rx_echo = htonl(0);
397 if (bfd_in_poll(bfd)) {
398 min_tx = bfd->poll_min_tx;
399 min_rx = bfd->poll_min_rx;
401 min_tx = bfd_min_tx(bfd);
402 min_rx = bfd->min_rx;
405 msg->min_tx = htonl(min_tx * 1000);
406 msg->min_rx = htonl(min_rx * 1000);
408 bfd->flags &= ~FLAG_FINAL;
410 log_msg(VLL_DBG, msg, "Sending BFD Message", bfd);
412 bfd->last_tx = time_msec();
413 bfd_set_next_tx(bfd);
417 bfd_should_process_flow(const struct flow *flow)
419 return (flow->dl_type == htons(ETH_TYPE_IP)
420 && flow->nw_proto == IPPROTO_UDP
421 && flow->tp_dst == htons(3784));
425 bfd_process_packet(struct bfd *bfd, const struct flow *flow,
426 const struct ofpbuf *p)
428 uint32_t rmt_min_rx, pkt_your_disc;
429 enum state rmt_state;
434 /* This function is designed to follow section RFC 5880 6.8.6 closely. */
436 if (flow->nw_ttl != 255) {
437 /* XXX Should drop in the kernel to prevent DOS. */
441 msg = ofpbuf_at(p, (uint8_t *)p->l7 - (uint8_t *)p->data, BFD_PACKET_LEN);
443 VLOG_INFO_RL(&rl, "%s: Received unparseable BFD control message.",
448 /* RFC 5880 Section 6.8.6
449 * If the Length field is greater than the payload of the encapsulating
450 * protocol, the packet MUST be discarded.
452 * Note that we make this check implicity. Above we use ofpbuf_at() to
453 * ensure that there are at least BFD_PACKET_LEN bytes in the payload of
454 * the encapsulating protocol. Below we require msg->length to be exactly
455 * BFD_PACKET_LEN bytes. */
457 flags = msg->flags & FLAGS_MASK;
458 rmt_state = msg->flags & STATE_MASK;
459 version = msg->vers_diag >> VERS_SHIFT;
461 log_msg(VLL_DBG, msg, "Received BFD control message", bfd);
463 if (version != BFD_VERSION) {
464 log_msg(VLL_WARN, msg, "Incorrect version", bfd);
468 /* Technically this should happen after the length check. We don't support
469 * authentication however, so it's simpler to do the check first. */
470 if (flags & FLAG_AUTH) {
471 log_msg(VLL_WARN, msg, "Authenticated control message with"
472 " authentication disabled", bfd);
476 if (msg->length != BFD_PACKET_LEN) {
477 log_msg(VLL_WARN, msg, "Unexpected length", bfd);
478 if (msg->length < BFD_PACKET_LEN) {
484 log_msg(VLL_WARN, msg, "Zero multiplier", bfd);
488 if (flags & FLAG_MULTIPOINT) {
489 log_msg(VLL_WARN, msg, "Unsupported multipoint flag", bfd);
494 log_msg(VLL_WARN, msg, "NULL my_disc", bfd);
498 pkt_your_disc = ntohl(msg->your_disc);
500 /* Technically, we should use the your discriminator field to figure
501 * out which 'struct bfd' this packet is destined towards. That way a
502 * bfd session could migrate from one interface to another
503 * transparently. This doesn't fit in with the OVS structure very
504 * well, so in this respect, we are not compliant. */
505 if (pkt_your_disc != bfd->disc) {
506 log_msg(VLL_WARN, msg, "Incorrect your_disc", bfd);
509 } else if (rmt_state > STATE_DOWN) {
510 log_msg(VLL_WARN, msg, "Null your_disc", bfd);
514 bfd->rmt_disc = ntohl(msg->my_disc);
515 bfd->rmt_state = rmt_state;
516 bfd->rmt_flags = flags;
517 bfd->rmt_diag = msg->vers_diag & DIAG_MASK;
519 if (flags & FLAG_FINAL && bfd_in_poll(bfd)) {
520 bfd->min_tx = bfd->poll_min_tx;
521 bfd->min_rx = bfd->poll_min_rx;
522 bfd->flags &= ~FLAG_POLL;
523 log_msg(VLL_INFO, msg, "Poll sequence terminated", bfd);
526 if (flags & FLAG_POLL) {
527 /* RFC 5880 Section 6.5
528 * When the other system receives a Poll, it immediately transmits a
529 * BFD Control packet with the Final (F) bit set, independent of any
530 * periodic BFD Control packets it may be sending
531 * (see section 6.8.7). */
532 bfd->flags &= ~FLAG_POLL;
533 bfd->flags |= FLAG_FINAL;
536 rmt_min_rx = MAX(ntohl(msg->min_rx) / 1000, 1);
537 if (bfd->rmt_min_rx != rmt_min_rx) {
538 bfd->rmt_min_rx = rmt_min_rx;
539 bfd_set_next_tx(bfd);
540 log_msg(VLL_INFO, msg, "New remote min_rx", bfd);
543 bfd->rmt_min_tx = MAX(ntohl(msg->min_tx) / 1000, 1);
544 bfd->detect_time = bfd_rx_interval(bfd) * bfd->mult + time_msec();
546 if (bfd->state == STATE_ADMIN_DOWN) {
547 VLOG_DBG_RL(&rl, "Administratively down, dropping control message.");
551 if (rmt_state == STATE_ADMIN_DOWN) {
552 if (bfd->state != STATE_DOWN) {
553 bfd_set_state(bfd, STATE_DOWN, DIAG_RMT_DOWN);
556 switch (bfd->state) {
558 if (rmt_state == STATE_DOWN) {
559 bfd_set_state(bfd, STATE_INIT, bfd->diag);
560 } else if (rmt_state == STATE_INIT) {
561 bfd_set_state(bfd, STATE_UP, bfd->diag);
565 if (rmt_state > STATE_DOWN) {
566 bfd_set_state(bfd, STATE_UP, bfd->diag);
570 if (rmt_state <= STATE_DOWN) {
571 bfd_set_state(bfd, STATE_DOWN, DIAG_RMT_DOWN);
572 log_msg(VLL_INFO, msg, "Remote signaled STATE_DOWN", bfd);
575 case STATE_ADMIN_DOWN:
580 /* XXX: RFC 5880 Section 6.8.6 Demand mode related calculations here. */
585 bfd_in_poll(const struct bfd *bfd)
587 return (bfd->flags & FLAG_POLL) != 0;
591 bfd_poll(struct bfd *bfd)
593 if (bfd->state > STATE_DOWN && !bfd_in_poll(bfd)
594 && !(bfd->flags & FLAG_FINAL)) {
595 bfd->poll_min_tx = bfd->cfg_min_tx;
596 bfd->poll_min_rx = bfd->cfg_min_rx;
597 bfd->flags |= FLAG_POLL;
599 VLOG_INFO_RL(&rl, "%s: Initiating poll sequence", bfd->name);
604 bfd_min_tx(const struct bfd *bfd)
606 /* RFC 5880 Section 6.8.3
607 * When bfd.SessionState is not Up, the system MUST set
608 * bfd.DesiredMinTxInterval to a value of not less than one second
609 * (1,000,000 microseconds). This is intended to ensure that the
610 * bandwidth consumed by BFD sessions that are not Up is negligible,
611 * particularly in the case where a neighbor may not be running BFD. */
612 return (bfd->state == STATE_UP ? bfd->min_tx : MAX(bfd->min_tx, 1000));
616 bfd_tx_interval(const struct bfd *bfd)
618 long long int interval = bfd_min_tx(bfd);
619 return MAX(interval, bfd->rmt_min_rx);
623 bfd_rx_interval(const struct bfd *bfd)
625 return MAX(bfd->min_rx, bfd->rmt_min_tx);
629 bfd_set_next_tx(struct bfd *bfd)
631 long long int interval = bfd_tx_interval(bfd);
632 interval -= interval * random_range(26) / 100;
633 bfd->next_tx = bfd->last_tx + interval;
637 bfd_flag_str(enum flags flags)
639 struct ds ds = DS_EMPTY_INITIALIZER;
640 static char flag_str[128];
646 if (flags & FLAG_MULTIPOINT) {
647 ds_put_cstr(&ds, "multipoint ");
650 if (flags & FLAG_DEMAND) {
651 ds_put_cstr(&ds, "demand ");
654 if (flags & FLAG_AUTH) {
655 ds_put_cstr(&ds, "auth ");
658 if (flags & FLAG_CTL) {
659 ds_put_cstr(&ds, "ctl ");
662 if (flags & FLAG_FINAL) {
663 ds_put_cstr(&ds, "final ");
666 if (flags & FLAG_POLL) {
667 ds_put_cstr(&ds, "poll ");
670 ovs_strlcpy(flag_str, ds_cstr(&ds), sizeof flag_str);
676 bfd_state_str(enum state state)
679 case STATE_ADMIN_DOWN: return "admin_down";
680 case STATE_DOWN: return "down";
681 case STATE_INIT: return "init";
682 case STATE_UP: return "up";
683 default: return "invalid";
688 bfd_diag_str(enum diag diag) {
690 case DIAG_NONE: return "No Diagnostic";
691 case DIAG_EXPIRED: return "Control Detection Time Expired";
692 case DIAG_ECHO_FAILED: return "Echo Function Failed";
693 case DIAG_RMT_DOWN: return "Neighbor Signaled Session Down";
694 case DIAG_FWD_RESET: return "Forwarding Plane Reset";
695 case DIAG_PATH_DOWN: return "Path Down";
696 case DIAG_CPATH_DOWN: return "Concatenated Path Down";
697 case DIAG_ADMIN_DOWN: return "Administratively Down";
698 case DIAG_RCPATH_DOWN: return "Reverse Concatenated Path Down";
699 default: return "Invalid Diagnostic";
704 log_msg(enum vlog_level level, const struct msg *p, const char *message,
705 const struct bfd *bfd)
707 struct ds ds = DS_EMPTY_INITIALIZER;
709 if (vlog_should_drop(THIS_MODULE, level, &rl)) {
715 "\n\tvers:%"PRIu8" diag:\"%s\" state:%s mult:%"PRIu8
718 "\n\tmy_disc:0x%"PRIx32" your_disc:0x%"PRIx32
719 "\n\tmin_tx:%"PRIu32"us (%"PRIu32"ms)"
720 "\n\tmin_rx:%"PRIu32"us (%"PRIu32"ms)"
721 "\n\tmin_rx_echo:%"PRIu32"us (%"PRIu32"ms)",
722 bfd->name, message, p->vers_diag >> VERS_SHIFT,
723 bfd_diag_str(p->vers_diag & DIAG_MASK),
724 bfd_state_str(p->flags & STATE_MASK),
725 p->mult, p->length, bfd_flag_str(p->flags & FLAGS_MASK),
726 ntohl(p->my_disc), ntohl(p->your_disc),
727 ntohl(p->min_tx), ntohl(p->min_tx) / 1000,
728 ntohl(p->min_rx), ntohl(p->min_rx) / 1000,
729 ntohl(p->min_rx_echo), ntohl(p->min_rx_echo) / 1000);
730 bfd_put_details(&ds, bfd);
731 VLOG(level, "%s", ds_cstr(&ds));
736 bfd_set_state(struct bfd *bfd, enum state state, enum diag diag)
738 if (diag == DIAG_NONE && bfd->cpath_down) {
739 diag = DIAG_CPATH_DOWN;
742 if (bfd->state != state || bfd->diag != diag) {
743 if (!VLOG_DROP_INFO(&rl)) {
744 struct ds ds = DS_EMPTY_INITIALIZER;
746 ds_put_format(&ds, "%s: BFD state change: %s->%s"
747 " \"%s\"->\"%s\".\n",
748 bfd->name, bfd_state_str(bfd->state),
749 bfd_state_str(state), bfd_diag_str(bfd->diag),
751 bfd_put_details(&ds, bfd);
752 VLOG_INFO("%s", ds_cstr(&ds));
759 if (bfd->state <= STATE_DOWN) {
760 bfd->rmt_state = STATE_DOWN;
761 bfd->rmt_diag = DIAG_NONE;
771 generate_discriminator(void)
775 /* RFC 5880 Section 6.8.1
776 * It SHOULD be set to a random (but still unique) value to improve
777 * security. The value is otherwise outside the scope of this
783 /* 'disc' is by defnition random, so there's no reason to waste time
785 disc = random_uint32();
786 HMAP_FOR_EACH_IN_BUCKET (bfd, node, disc, &all_bfds) {
787 if (bfd->disc == disc) {
798 bfd_find_by_name(const char *name)
802 HMAP_FOR_EACH (bfd, node, &all_bfds) {
803 if (!strcmp(bfd->name, name)) {
811 bfd_put_details(struct ds *ds, const struct bfd *bfd)
813 ds_put_format(ds, "\tForwarding: %s\n",
814 bfd_forwarding(bfd) ? "true" : "false");
815 ds_put_format(ds, "\tDetect Multiplier: %d\n", bfd->mult);
816 ds_put_format(ds, "\tConcatenated Path Down: %s\n",
817 bfd->cpath_down ? "true" : "false");
818 ds_put_format(ds, "\tTX Interval: Approx %lldms\n", bfd_tx_interval(bfd));
819 ds_put_format(ds, "\tRX Interval: Approx %lldms\n", bfd_rx_interval(bfd));
820 ds_put_format(ds, "\tDetect Time: now %+lldms\n",
821 time_msec() - bfd->detect_time);
822 ds_put_format(ds, "\tNext TX Time: now %+lldms\n",
823 time_msec() - bfd->next_tx);
824 ds_put_format(ds, "\tLast TX Time: now %+lldms\n",
825 time_msec() - bfd->last_tx);
827 ds_put_cstr(ds, "\n");
829 ds_put_format(ds, "\tLocal Flags: %s\n", bfd_flag_str(bfd->flags));
830 ds_put_format(ds, "\tLocal Session State: %s\n",
831 bfd_state_str(bfd->state));
832 ds_put_format(ds, "\tLocal Diagnostic: %s\n", bfd_diag_str(bfd->diag));
833 ds_put_format(ds, "\tLocal Discriminator: 0x%"PRIx32"\n", bfd->disc);
834 ds_put_format(ds, "\tLocal Minimum TX Interval: %lldms\n",
836 ds_put_format(ds, "\tLocal Minimum RX Interval: %lldms\n", bfd->min_rx);
838 ds_put_cstr(ds, "\n");
840 ds_put_format(ds, "\tRemote Flags: %s\n", bfd_flag_str(bfd->rmt_flags));
841 ds_put_format(ds, "\tRemote Session State: %s\n",
842 bfd_state_str(bfd->rmt_state));
843 ds_put_format(ds, "\tRemote Diagnostic: %s\n",
844 bfd_diag_str(bfd->rmt_diag));
845 ds_put_format(ds, "\tRemote Discriminator: 0x%"PRIx32"\n", bfd->rmt_disc);
846 ds_put_format(ds, "\tRemote Minimum TX Interval: %lldms\n",
848 ds_put_format(ds, "\tRemote Minimum RX Interval: %lldms\n",
853 bfd_unixctl_show(struct unixctl_conn *conn, int argc, const char *argv[],
854 void *aux OVS_UNUSED)
856 struct ds ds = DS_EMPTY_INITIALIZER;
860 bfd = bfd_find_by_name(argv[1]);
862 unixctl_command_reply_error(conn, "no such bfd object");
865 bfd_put_details(&ds, bfd);
867 HMAP_FOR_EACH (bfd, node, &all_bfds) {
868 ds_put_format(&ds, "---- %s ----\n", bfd->name);
869 bfd_put_details(&ds, bfd);
872 unixctl_command_reply(conn, ds_cstr(&ds));