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'. */
234 bfd_configure(struct bfd *bfd, const char *name,
235 const struct smap *cfg)
237 static uint16_t udp_src = 0;
238 static bool init = false;
240 long long int min_tx, min_rx;
244 unixctl_command_register("bfd/show", "[interface]", 0, 1,
245 bfd_unixctl_show, NULL);
249 if (!smap_get_bool(cfg, "enable", false)) {
251 hmap_remove(&all_bfds, &bfd->node);
259 bfd = xzalloc(sizeof *bfd);
260 bfd->name = xstrdup(name);
261 bfd->disc = generate_discriminator();
262 hmap_insert(&all_bfds, &bfd->node, bfd->disc);
264 bfd->diag = DIAG_NONE;
268 /* RFC 5881 section 4
269 * The source port MUST be in the range 49152 through 65535. The same
270 * UDP source port number MUST be used for all BFD Control packets
271 * associated with a particular session. The source port number SHOULD
272 * be unique among all BFD sessions on the system. */
273 bfd->udp_src = (udp_src++ % 16384) + 49152;
275 bfd_set_state(bfd, STATE_DOWN, DIAG_NONE);
278 min_tx = smap_get_int(cfg, "min_tx", 100);
279 min_tx = MAX(min_tx, 100);
280 if (bfd->cfg_min_tx != min_tx) {
281 bfd->cfg_min_tx = min_tx;
282 if (bfd->state != STATE_UP
283 || (!bfd_in_poll(bfd) && bfd->cfg_min_tx < bfd->min_tx)) {
284 bfd->min_tx = bfd->cfg_min_tx;
289 min_rx = smap_get_int(cfg, "min_rx", 1000);
290 min_rx = MAX(min_rx, 100);
291 if (bfd->cfg_min_rx != min_rx) {
292 bfd->cfg_min_rx = min_rx;
293 if (bfd->state != STATE_UP
294 || (!bfd_in_poll(bfd) && bfd->cfg_min_rx > bfd->min_rx)) {
295 bfd->min_rx = bfd->cfg_min_rx;
300 cpath_down = smap_get_bool(cfg, "cpath_down", false);
301 if (bfd->cpath_down != cpath_down) {
302 bfd->cpath_down = cpath_down;
303 if (bfd->diag == DIAG_NONE || bfd->diag == DIAG_CPATH_DOWN) {
304 bfd_set_state(bfd, bfd->state, DIAG_NONE);
312 bfd_wait(const struct bfd *bfd)
314 if (bfd->flags & FLAG_FINAL) {
315 poll_immediate_wake();
318 poll_timer_wait_until(bfd->next_tx);
319 if (bfd->state > STATE_DOWN) {
320 poll_timer_wait_until(bfd->detect_time);
325 bfd_run(struct bfd *bfd)
327 if (bfd->state > STATE_DOWN && time_msec() >= bfd->detect_time) {
328 bfd_set_state(bfd, STATE_DOWN, DIAG_EXPIRED);
331 if (bfd->min_tx != bfd->cfg_min_tx || bfd->min_rx != bfd->cfg_min_rx) {
337 bfd_should_send_packet(const struct bfd *bfd)
339 return bfd->flags & FLAG_FINAL || time_msec() >= bfd->next_tx;
343 bfd_put_packet(struct bfd *bfd, struct ofpbuf *p,
344 uint8_t eth_src[ETH_ADDR_LEN])
346 long long int min_tx, min_rx;
347 struct udp_header *udp;
348 struct eth_header *eth;
349 struct ip_header *ip;
353 long long int delay = time_msec() - bfd->next_tx;
354 long long int interval = bfd_tx_interval(bfd);
355 if (delay > interval * 3 / 2) {
356 VLOG_WARN("%s: long delay of %lldms (expected %lldms) sending BFD"
357 " control message", bfd->name, delay, interval);
361 /* RFC 5880 Section 6.5
362 * A BFD Control packet MUST NOT have both the Poll (P) and Final (F) bits
364 ovs_assert(!(bfd->flags & FLAG_POLL) || !(bfd->flags & FLAG_FINAL));
366 ofpbuf_reserve(p, 2); /* Properly align after the ethernet header. */
367 eth = ofpbuf_put_uninit(p, sizeof *eth);
368 memcpy(eth->eth_dst, eth_addr_broadcast, ETH_ADDR_LEN);
369 memcpy(eth->eth_src, eth_src, ETH_ADDR_LEN);
370 eth->eth_type = htons(ETH_TYPE_IP);
372 ip = ofpbuf_put_zeros(p, sizeof *ip);
373 ip->ip_ihl_ver = IP_IHL_VER(5, 4);
374 ip->ip_tot_len = htons(sizeof *ip + sizeof *udp + sizeof *msg);
376 ip->ip_proto = IPPROTO_UDP;
377 ip->ip_src = htonl(0xA9FE0100); /* 169.254.1.0 Link Local. */
378 ip->ip_dst = htonl(0xA9FE0101); /* 169.254.1.1 Link Local. */
379 ip->ip_csum = csum(ip, sizeof *ip);
381 udp = ofpbuf_put_zeros(p, sizeof *udp);
382 udp->udp_src = htons(bfd->udp_src);
383 udp->udp_dst = htons(BFD_DEST_PORT);
384 udp->udp_len = htons(sizeof *udp + sizeof *msg);
386 msg = ofpbuf_put_uninit(p, sizeof *msg);
387 msg->vers_diag = (BFD_VERSION << 5) | bfd->diag;
388 msg->flags = (bfd->state & STATE_MASK) | bfd->flags;
390 msg->mult = bfd->mult;
391 msg->length = BFD_PACKET_LEN;
392 msg->my_disc = htonl(bfd->disc);
393 msg->your_disc = htonl(bfd->rmt_disc);
394 msg->min_rx_echo = htonl(0);
396 if (bfd_in_poll(bfd)) {
397 min_tx = bfd->poll_min_tx;
398 min_rx = bfd->poll_min_rx;
400 min_tx = bfd_min_tx(bfd);
401 min_rx = bfd->min_rx;
404 msg->min_tx = htonl(min_tx * 1000);
405 msg->min_rx = htonl(min_rx * 1000);
407 bfd->flags &= ~FLAG_FINAL;
409 log_msg(VLL_DBG, msg, "Sending BFD Message", bfd);
411 bfd->last_tx = time_msec();
412 bfd_set_next_tx(bfd);
416 bfd_should_process_flow(const struct flow *flow)
418 return (flow->dl_type == htons(ETH_TYPE_IP)
419 && flow->nw_proto == IPPROTO_UDP
420 && flow->tp_dst == htons(3784));
424 bfd_process_packet(struct bfd *bfd, const struct flow *flow,
425 const struct ofpbuf *p)
427 uint32_t rmt_min_rx, pkt_your_disc;
428 enum state rmt_state;
433 /* This function is designed to follow section RFC 5880 6.8.6 closely. */
435 if (flow->nw_ttl != 255) {
436 /* XXX Should drop in the kernel to prevent DOS. */
440 msg = ofpbuf_at(p, (uint8_t *)p->l7 - (uint8_t *)p->data, BFD_PACKET_LEN);
442 VLOG_INFO_RL(&rl, "%s: Received unparseable BFD control message.",
447 /* RFC 5880 Section 6.8.6
448 * If the Length field is greater than the payload of the encapsulating
449 * protocol, the packet MUST be discarded.
451 * Note that we make this check implicity. Above we use ofpbuf_at() to
452 * ensure that there are at least BFD_PACKET_LEN bytes in the payload of
453 * the encapsulating protocol. Below we require msg->length to be exactly
454 * BFD_PACKET_LEN bytes. */
456 flags = msg->flags & FLAGS_MASK;
457 rmt_state = msg->flags & STATE_MASK;
458 version = msg->vers_diag >> VERS_SHIFT;
460 log_msg(VLL_DBG, msg, "Received BFD control message", bfd);
462 if (version != BFD_VERSION) {
463 log_msg(VLL_WARN, msg, "Incorrect version", bfd);
467 /* Technically this should happen after the length check. We don't support
468 * authentication however, so it's simpler to do the check first. */
469 if (flags & FLAG_AUTH) {
470 log_msg(VLL_WARN, msg, "Authenticated control message with"
471 " authentication disabled", bfd);
475 if (msg->length != BFD_PACKET_LEN) {
476 log_msg(VLL_WARN, msg, "Unexpected length", bfd);
477 if (msg->length < BFD_PACKET_LEN) {
483 log_msg(VLL_WARN, msg, "Zero multiplier", bfd);
487 if (flags & FLAG_MULTIPOINT) {
488 log_msg(VLL_WARN, msg, "Unsupported multipoint flag", bfd);
493 log_msg(VLL_WARN, msg, "NULL my_disc", bfd);
497 pkt_your_disc = ntohl(msg->your_disc);
499 /* Technically, we should use the your discriminator field to figure
500 * out which 'struct bfd' this packet is destined towards. That way a
501 * bfd session could migrate from one interface to another
502 * transparently. This doesn't fit in with the OVS structure very
503 * well, so in this respect, we are not compliant. */
504 if (pkt_your_disc != bfd->disc) {
505 log_msg(VLL_WARN, msg, "Incorrect your_disc", bfd);
508 } else if (rmt_state > STATE_DOWN) {
509 log_msg(VLL_WARN, msg, "Null your_disc", bfd);
513 bfd->rmt_disc = ntohl(msg->my_disc);
514 bfd->rmt_state = rmt_state;
515 bfd->rmt_flags = flags;
516 bfd->rmt_diag = msg->vers_diag & DIAG_MASK;
518 if (flags & FLAG_FINAL && bfd_in_poll(bfd)) {
519 bfd->min_tx = bfd->poll_min_tx;
520 bfd->min_rx = bfd->poll_min_rx;
521 bfd->flags &= ~FLAG_POLL;
522 log_msg(VLL_INFO, msg, "Poll sequence terminated", bfd);
525 if (flags & FLAG_POLL) {
526 /* RFC 5880 Section 6.5
527 * When the other system receives a Poll, it immediately transmits a
528 * BFD Control packet with the Final (F) bit set, independent of any
529 * periodic BFD Control packets it may be sending
530 * (see section 6.8.7). */
531 bfd->flags &= ~FLAG_POLL;
532 bfd->flags |= FLAG_FINAL;
535 rmt_min_rx = MAX(ntohl(msg->min_rx) / 1000, 1);
536 if (bfd->rmt_min_rx != rmt_min_rx) {
537 bfd->rmt_min_rx = rmt_min_rx;
538 bfd_set_next_tx(bfd);
539 log_msg(VLL_INFO, msg, "New remote min_rx", bfd);
542 bfd->rmt_min_tx = MAX(ntohl(msg->min_tx) / 1000, 1);
543 bfd->detect_time = bfd_rx_interval(bfd) * bfd->mult + time_msec();
545 if (bfd->state == STATE_ADMIN_DOWN) {
546 VLOG_DBG_RL(&rl, "Administratively down, dropping control message.");
550 if (rmt_state == STATE_ADMIN_DOWN) {
551 if (bfd->state != STATE_DOWN) {
552 bfd_set_state(bfd, STATE_DOWN, DIAG_RMT_DOWN);
555 switch (bfd->state) {
557 if (rmt_state == STATE_DOWN) {
558 bfd_set_state(bfd, STATE_INIT, bfd->diag);
559 } else if (rmt_state == STATE_INIT) {
560 bfd_set_state(bfd, STATE_UP, bfd->diag);
564 if (rmt_state > STATE_DOWN) {
565 bfd_set_state(bfd, STATE_UP, bfd->diag);
569 if (rmt_state <= STATE_DOWN) {
570 bfd_set_state(bfd, STATE_DOWN, DIAG_RMT_DOWN);
571 log_msg(VLL_INFO, msg, "Remote signaled STATE_DOWN", bfd);
574 case STATE_ADMIN_DOWN:
579 /* XXX: RFC 5880 Section 6.8.6 Demand mode related calculations here. */
584 bfd_in_poll(const struct bfd *bfd)
586 return (bfd->flags & FLAG_POLL) != 0;
590 bfd_poll(struct bfd *bfd)
592 if (bfd->state > STATE_DOWN && !bfd_in_poll(bfd)
593 && !(bfd->flags & FLAG_FINAL)) {
594 bfd->poll_min_tx = bfd->cfg_min_tx;
595 bfd->poll_min_rx = bfd->cfg_min_rx;
596 bfd->flags |= FLAG_POLL;
598 VLOG_INFO_RL(&rl, "%s: Initiating poll sequence", bfd->name);
603 bfd_min_tx(const struct bfd *bfd)
605 /* RFC 5880 Section 6.8.3
606 * When bfd.SessionState is not Up, the system MUST set
607 * bfd.DesiredMinTxInterval to a value of not less than one second
608 * (1,000,000 microseconds). This is intended to ensure that the
609 * bandwidth consumed by BFD sessions that are not Up is negligible,
610 * particularly in the case where a neighbor may not be running BFD. */
611 return (bfd->state == STATE_UP ? bfd->min_tx : MAX(bfd->min_tx, 1000));
615 bfd_tx_interval(const struct bfd *bfd)
617 long long int interval = bfd_min_tx(bfd);
618 return MAX(interval, bfd->rmt_min_rx);
622 bfd_rx_interval(const struct bfd *bfd)
624 return MAX(bfd->min_rx, bfd->rmt_min_tx);
628 bfd_set_next_tx(struct bfd *bfd)
630 long long int interval = bfd_tx_interval(bfd);
631 interval -= interval * random_range(26) / 100;
632 bfd->next_tx = bfd->last_tx + interval;
636 bfd_flag_str(enum flags flags)
638 struct ds ds = DS_EMPTY_INITIALIZER;
639 static char flag_str[128];
645 if (flags & FLAG_MULTIPOINT) {
646 ds_put_cstr(&ds, "multipoint ");
649 if (flags & FLAG_DEMAND) {
650 ds_put_cstr(&ds, "demand ");
653 if (flags & FLAG_AUTH) {
654 ds_put_cstr(&ds, "auth ");
657 if (flags & FLAG_CTL) {
658 ds_put_cstr(&ds, "ctl ");
661 if (flags & FLAG_FINAL) {
662 ds_put_cstr(&ds, "final ");
665 if (flags & FLAG_POLL) {
666 ds_put_cstr(&ds, "poll ");
669 ovs_strlcpy(flag_str, ds_cstr(&ds), sizeof flag_str);
675 bfd_state_str(enum state state)
678 case STATE_ADMIN_DOWN: return "admin_down";
679 case STATE_DOWN: return "down";
680 case STATE_INIT: return "init";
681 case STATE_UP: return "up";
682 default: return "invalid";
687 bfd_diag_str(enum diag diag) {
689 case DIAG_NONE: return "No Diagnostic";
690 case DIAG_EXPIRED: return "Control Detection Time Expired";
691 case DIAG_ECHO_FAILED: return "Echo Function Failed";
692 case DIAG_RMT_DOWN: return "Neighbor Signaled Session Down";
693 case DIAG_FWD_RESET: return "Forwarding Plane Reset";
694 case DIAG_PATH_DOWN: return "Path Down";
695 case DIAG_CPATH_DOWN: return "Concatenated Path Down";
696 case DIAG_ADMIN_DOWN: return "Administratively Down";
697 case DIAG_RCPATH_DOWN: return "Reverse Concatenated Path Down";
698 default: return "Invalid Diagnostic";
703 log_msg(enum vlog_level level, const struct msg *p, const char *message,
704 const struct bfd *bfd)
706 struct ds ds = DS_EMPTY_INITIALIZER;
708 if (vlog_should_drop(THIS_MODULE, level, &rl)) {
714 "\n\tvers:%"PRIu8" diag:\"%s\" state:%s mult:%"PRIu8
717 "\n\tmy_disc:0x%"PRIx32" your_disc:0x%"PRIx32
718 "\n\tmin_tx:%"PRIu32"us (%"PRIu32"ms)"
719 "\n\tmin_rx:%"PRIu32"us (%"PRIu32"ms)"
720 "\n\tmin_rx_echo:%"PRIu32"us (%"PRIu32"ms)",
721 bfd->name, message, p->vers_diag >> VERS_SHIFT,
722 bfd_diag_str(p->vers_diag & DIAG_MASK),
723 bfd_state_str(p->flags & STATE_MASK),
724 p->mult, p->length, bfd_flag_str(p->flags & FLAGS_MASK),
725 ntohl(p->my_disc), ntohl(p->your_disc),
726 ntohl(p->min_tx), ntohl(p->min_tx) / 1000,
727 ntohl(p->min_rx), ntohl(p->min_rx) / 1000,
728 ntohl(p->min_rx_echo), ntohl(p->min_rx_echo) / 1000);
729 bfd_put_details(&ds, bfd);
730 VLOG(level, "%s", ds_cstr(&ds));
735 bfd_set_state(struct bfd *bfd, enum state state, enum diag diag)
737 if (diag == DIAG_NONE && bfd->cpath_down) {
738 diag = DIAG_CPATH_DOWN;
741 if (bfd->state != state || bfd->diag != diag) {
742 if (!VLOG_DROP_INFO(&rl)) {
743 struct ds ds = DS_EMPTY_INITIALIZER;
745 ds_put_format(&ds, "%s: BFD state change: %s->%s"
746 " \"%s\"->\"%s\".\n",
747 bfd->name, bfd_state_str(bfd->state),
748 bfd_state_str(state), bfd_diag_str(bfd->diag),
750 bfd_put_details(&ds, bfd);
751 VLOG_INFO("%s", ds_cstr(&ds));
758 if (bfd->state <= STATE_DOWN) {
759 bfd->rmt_state = STATE_DOWN;
760 bfd->rmt_diag = DIAG_NONE;
770 generate_discriminator(void)
774 /* RFC 5880 Section 6.8.1
775 * It SHOULD be set to a random (but still unique) value to improve
776 * security. The value is otherwise outside the scope of this
782 /* 'disc' is by defnition random, so there's no reason to waste time
784 disc = random_uint32();
785 HMAP_FOR_EACH_IN_BUCKET (bfd, node, disc, &all_bfds) {
786 if (bfd->disc == disc) {
797 bfd_find_by_name(const char *name)
801 HMAP_FOR_EACH (bfd, node, &all_bfds) {
802 if (!strcmp(bfd->name, name)) {
810 bfd_put_details(struct ds *ds, const struct bfd *bfd)
812 ds_put_format(ds, "\tForwarding: %s\n",
813 bfd_forwarding(bfd) ? "true" : "false");
814 ds_put_format(ds, "\tDetect Multiplier: %d\n", bfd->mult);
815 ds_put_format(ds, "\tConcatenated Path Down: %s\n",
816 bfd->cpath_down ? "true" : "false");
817 ds_put_format(ds, "\tTX Interval: Approx %lldms\n", bfd_tx_interval(bfd));
818 ds_put_format(ds, "\tRX Interval: Approx %lldms\n", bfd_rx_interval(bfd));
819 ds_put_format(ds, "\tDetect Time: now %+lldms\n",
820 time_msec() - bfd->detect_time);
821 ds_put_format(ds, "\tNext TX Time: now %+lldms\n",
822 time_msec() - bfd->next_tx);
823 ds_put_format(ds, "\tLast TX Time: now %+lldms\n",
824 time_msec() - bfd->last_tx);
826 ds_put_cstr(ds, "\n");
828 ds_put_format(ds, "\tLocal Flags: %s\n", bfd_flag_str(bfd->flags));
829 ds_put_format(ds, "\tLocal Session State: %s\n",
830 bfd_state_str(bfd->state));
831 ds_put_format(ds, "\tLocal Diagnostic: %s\n", bfd_diag_str(bfd->diag));
832 ds_put_format(ds, "\tLocal Discriminator: 0x%"PRIx32"\n", bfd->disc);
833 ds_put_format(ds, "\tLocal Minimum TX Interval: %lldms\n",
835 ds_put_format(ds, "\tLocal Minimum RX Interval: %lldms\n", bfd->min_rx);
837 ds_put_cstr(ds, "\n");
839 ds_put_format(ds, "\tRemote Flags: %s\n", bfd_flag_str(bfd->rmt_flags));
840 ds_put_format(ds, "\tRemote Session State: %s\n",
841 bfd_state_str(bfd->rmt_state));
842 ds_put_format(ds, "\tRemote Diagnostic: %s\n",
843 bfd_diag_str(bfd->rmt_diag));
844 ds_put_format(ds, "\tRemote Discriminator: 0x%"PRIx32"\n", bfd->rmt_disc);
845 ds_put_format(ds, "\tRemote Minimum TX Interval: %lldms\n",
847 ds_put_format(ds, "\tRemote Minimum RX Interval: %lldms\n",
852 bfd_unixctl_show(struct unixctl_conn *conn, int argc, const char *argv[],
853 void *aux OVS_UNUSED)
855 struct ds ds = DS_EMPTY_INITIALIZER;
859 bfd = bfd_find_by_name(argv[1]);
861 unixctl_command_reply_error(conn, "no such bfd object");
864 bfd_put_details(&ds, bfd);
866 HMAP_FOR_EACH (bfd, node, &all_bfds) {
867 ds_put_format(&ds, "---- %s ----\n", bfd->name);
868 bfd_put_details(&ds, bfd);
871 unixctl_command_reply(conn, ds_cstr(&ds));