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 int forwarding_override
; /* Manual override of 'forwarding' status. */
187 static bool bfd_in_poll(const struct bfd
*);
188 static void bfd_poll(struct bfd
*bfd
);
189 static const char *bfd_diag_str(enum diag
);
190 static const char *bfd_state_str(enum state
);
191 static long long int bfd_min_tx(const struct bfd
*);
192 static long long int bfd_tx_interval(const struct bfd
*);
193 static long long int bfd_rx_interval(const struct bfd
*);
194 static void bfd_set_next_tx(struct bfd
*);
195 static void bfd_set_state(struct bfd
*, enum state
, enum diag
);
196 static uint32_t generate_discriminator(void);
197 static void bfd_put_details(struct ds
*, const struct bfd
*);
198 static void bfd_unixctl_show(struct unixctl_conn
*, int argc
,
199 const char *argv
[], void *aux OVS_UNUSED
);
200 static void bfd_unixctl_set_forwarding_override(struct unixctl_conn
*,
201 int argc
, const char *argv
[],
202 void *aux OVS_UNUSED
);
203 static void log_msg(enum vlog_level
, const struct msg
*, const char *message
,
206 static struct vlog_rate_limit rl
= VLOG_RATE_LIMIT_INIT(20, 20);
207 static struct hmap all_bfds
= HMAP_INITIALIZER(&all_bfds
);
209 /* Returns true if the interface on which 'bfd' is running may be used to
210 * forward traffic according to the BFD session state. */
212 bfd_forwarding(const struct bfd
*bfd
)
214 if (bfd
->forwarding_override
!= -1) {
215 return bfd
->forwarding_override
== 1;
218 return bfd
->state
== STATE_UP
219 && bfd
->rmt_diag
!= DIAG_PATH_DOWN
220 && bfd
->rmt_diag
!= DIAG_CPATH_DOWN
221 && bfd
->rmt_diag
!= DIAG_RCPATH_DOWN
;
224 /* Returns a 'smap' of key value pairs representing the status of 'bfd'
225 * intended for the OVS database. */
227 bfd_get_status(const struct bfd
*bfd
, struct smap
*smap
)
229 smap_add(smap
, "forwarding", bfd_forwarding(bfd
) ? "true" : "false");
230 smap_add(smap
, "state", bfd_state_str(bfd
->state
));
231 smap_add(smap
, "diagnostic", bfd_diag_str(bfd
->diag
));
233 if (bfd
->state
!= STATE_DOWN
) {
234 smap_add(smap
, "remote_state", bfd_state_str(bfd
->rmt_state
));
235 smap_add(smap
, "remote_diagnostic", bfd_diag_str(bfd
->rmt_diag
));
239 /* Initializes, destroys, or reconfigures the BFD session 'bfd' (named 'name'),
240 * according to the database configuration contained in 'cfg'. Takes ownership
241 * of 'bfd', which may be NULL. Returns a BFD object which may be used as a
242 * handle for the session, or NULL if BFD is not enabled according to 'cfg'.
243 * Also returns NULL if cfg is NULL. */
245 bfd_configure(struct bfd
*bfd
, const char *name
,
246 const struct smap
*cfg
)
248 static uint16_t udp_src
= 0;
249 static bool init
= false;
251 long long int min_tx
, min_rx
;
255 unixctl_command_register("bfd/show", "[interface]", 0, 1,
256 bfd_unixctl_show
, NULL
);
257 unixctl_command_register("bfd/set-forwarding",
258 "[interface] normal|false|true", 1, 2,
259 bfd_unixctl_set_forwarding_override
, NULL
);
263 if (!cfg
|| !smap_get_bool(cfg
, "enable", false)) {
269 bfd
= xzalloc(sizeof *bfd
);
270 bfd
->name
= xstrdup(name
);
271 bfd
->forwarding_override
= -1;
272 bfd
->disc
= generate_discriminator();
273 hmap_insert(&all_bfds
, &bfd
->node
, bfd
->disc
);
275 bfd
->diag
= DIAG_NONE
;
280 /* RFC 5881 section 4
281 * The source port MUST be in the range 49152 through 65535. The same
282 * UDP source port number MUST be used for all BFD Control packets
283 * associated with a particular session. The source port number SHOULD
284 * be unique among all BFD sessions on the system. */
285 bfd
->udp_src
= (udp_src
++ % 16384) + 49152;
287 bfd_set_state(bfd
, STATE_DOWN
, DIAG_NONE
);
290 min_tx
= smap_get_int(cfg
, "min_tx", 100);
291 min_tx
= MAX(min_tx
, 100);
292 if (bfd
->cfg_min_tx
!= min_tx
) {
293 bfd
->cfg_min_tx
= min_tx
;
294 if (bfd
->state
!= STATE_UP
295 || (!bfd_in_poll(bfd
) && bfd
->cfg_min_tx
< bfd
->min_tx
)) {
296 bfd
->min_tx
= bfd
->cfg_min_tx
;
301 min_rx
= smap_get_int(cfg
, "min_rx", 1000);
302 min_rx
= MAX(min_rx
, 100);
303 if (bfd
->cfg_min_rx
!= min_rx
) {
304 bfd
->cfg_min_rx
= min_rx
;
305 if (bfd
->state
!= STATE_UP
306 || (!bfd_in_poll(bfd
) && bfd
->cfg_min_rx
> bfd
->min_rx
)) {
307 bfd
->min_rx
= bfd
->cfg_min_rx
;
312 cpath_down
= smap_get_bool(cfg
, "cpath_down", false);
313 if (bfd
->cpath_down
!= cpath_down
) {
314 bfd
->cpath_down
= cpath_down
;
315 if (bfd
->diag
== DIAG_NONE
|| bfd
->diag
== DIAG_CPATH_DOWN
) {
316 bfd_set_state(bfd
, bfd
->state
, DIAG_NONE
);
324 bfd_ref(const struct bfd
*bfd_
)
326 struct bfd
*bfd
= CONST_CAST(struct bfd
*, bfd_
);
328 ovs_assert(bfd
->ref_cnt
> 0);
335 bfd_unref(struct bfd
*bfd
)
338 ovs_assert(bfd
->ref_cnt
> 0);
339 if (!--bfd
->ref_cnt
) {
340 hmap_remove(&all_bfds
, &bfd
->node
);
348 bfd_wait(const struct bfd
*bfd
)
350 if (bfd
->flags
& FLAG_FINAL
) {
351 poll_immediate_wake();
354 poll_timer_wait_until(bfd
->next_tx
);
355 if (bfd
->state
> STATE_DOWN
) {
356 poll_timer_wait_until(bfd
->detect_time
);
361 bfd_run(struct bfd
*bfd
)
363 if (bfd
->state
> STATE_DOWN
&& time_msec() >= bfd
->detect_time
) {
364 bfd_set_state(bfd
, STATE_DOWN
, DIAG_EXPIRED
);
367 if (bfd
->min_tx
!= bfd
->cfg_min_tx
|| bfd
->min_rx
!= bfd
->cfg_min_rx
) {
373 bfd_should_send_packet(const struct bfd
*bfd
)
375 return bfd
->flags
& FLAG_FINAL
|| time_msec() >= bfd
->next_tx
;
379 bfd_put_packet(struct bfd
*bfd
, struct ofpbuf
*p
,
380 uint8_t eth_src
[ETH_ADDR_LEN
])
382 long long int min_tx
, min_rx
;
383 struct udp_header
*udp
;
384 struct eth_header
*eth
;
385 struct ip_header
*ip
;
389 long long int delay
= time_msec() - bfd
->next_tx
;
390 long long int interval
= bfd_tx_interval(bfd
);
391 if (delay
> interval
* 3 / 2) {
392 VLOG_WARN("%s: long delay of %lldms (expected %lldms) sending BFD"
393 " control message", bfd
->name
, delay
, interval
);
397 /* RFC 5880 Section 6.5
398 * A BFD Control packet MUST NOT have both the Poll (P) and Final (F) bits
400 ovs_assert(!(bfd
->flags
& FLAG_POLL
) || !(bfd
->flags
& FLAG_FINAL
));
402 ofpbuf_reserve(p
, 2); /* Properly align after the ethernet header. */
403 eth
= ofpbuf_put_uninit(p
, sizeof *eth
);
404 memcpy(eth
->eth_dst
, eth_addr_broadcast
, ETH_ADDR_LEN
);
405 memcpy(eth
->eth_src
, eth_src
, ETH_ADDR_LEN
);
406 eth
->eth_type
= htons(ETH_TYPE_IP
);
408 ip
= ofpbuf_put_zeros(p
, sizeof *ip
);
409 ip
->ip_ihl_ver
= IP_IHL_VER(5, 4);
410 ip
->ip_tot_len
= htons(sizeof *ip
+ sizeof *udp
+ sizeof *msg
);
412 ip
->ip_proto
= IPPROTO_UDP
;
413 ip
->ip_src
= htonl(0xA9FE0100); /* 169.254.1.0 Link Local. */
414 ip
->ip_dst
= htonl(0xA9FE0101); /* 169.254.1.1 Link Local. */
415 ip
->ip_csum
= csum(ip
, sizeof *ip
);
417 udp
= ofpbuf_put_zeros(p
, sizeof *udp
);
418 udp
->udp_src
= htons(bfd
->udp_src
);
419 udp
->udp_dst
= htons(BFD_DEST_PORT
);
420 udp
->udp_len
= htons(sizeof *udp
+ sizeof *msg
);
422 msg
= ofpbuf_put_uninit(p
, sizeof *msg
);
423 msg
->vers_diag
= (BFD_VERSION
<< 5) | bfd
->diag
;
424 msg
->flags
= (bfd
->state
& STATE_MASK
) | bfd
->flags
;
426 msg
->mult
= bfd
->mult
;
427 msg
->length
= BFD_PACKET_LEN
;
428 msg
->my_disc
= htonl(bfd
->disc
);
429 msg
->your_disc
= htonl(bfd
->rmt_disc
);
430 msg
->min_rx_echo
= htonl(0);
432 if (bfd_in_poll(bfd
)) {
433 min_tx
= bfd
->poll_min_tx
;
434 min_rx
= bfd
->poll_min_rx
;
436 min_tx
= bfd_min_tx(bfd
);
437 min_rx
= bfd
->min_rx
;
440 msg
->min_tx
= htonl(min_tx
* 1000);
441 msg
->min_rx
= htonl(min_rx
* 1000);
443 bfd
->flags
&= ~FLAG_FINAL
;
445 log_msg(VLL_DBG
, msg
, "Sending BFD Message", bfd
);
447 bfd
->last_tx
= time_msec();
448 bfd_set_next_tx(bfd
);
452 bfd_should_process_flow(const struct flow
*flow
, struct flow_wildcards
*wc
)
454 memset(&wc
->masks
.nw_proto
, 0xff, sizeof wc
->masks
.nw_proto
);
455 memset(&wc
->masks
.tp_dst
, 0xff, sizeof wc
->masks
.tp_dst
);
456 return (flow
->dl_type
== htons(ETH_TYPE_IP
)
457 && flow
->nw_proto
== IPPROTO_UDP
458 && flow
->tp_dst
== htons(3784));
462 bfd_process_packet(struct bfd
*bfd
, const struct flow
*flow
,
463 const struct ofpbuf
*p
)
465 uint32_t rmt_min_rx
, pkt_your_disc
;
466 enum state rmt_state
;
471 /* This function is designed to follow section RFC 5880 6.8.6 closely. */
473 if (flow
->nw_ttl
!= 255) {
474 /* XXX Should drop in the kernel to prevent DOS. */
478 msg
= ofpbuf_at(p
, (uint8_t *)p
->l7
- (uint8_t *)p
->data
, BFD_PACKET_LEN
);
480 VLOG_INFO_RL(&rl
, "%s: Received unparseable BFD control message.",
485 /* RFC 5880 Section 6.8.6
486 * If the Length field is greater than the payload of the encapsulating
487 * protocol, the packet MUST be discarded.
489 * Note that we make this check implicity. Above we use ofpbuf_at() to
490 * ensure that there are at least BFD_PACKET_LEN bytes in the payload of
491 * the encapsulating protocol. Below we require msg->length to be exactly
492 * BFD_PACKET_LEN bytes. */
494 flags
= msg
->flags
& FLAGS_MASK
;
495 rmt_state
= msg
->flags
& STATE_MASK
;
496 version
= msg
->vers_diag
>> VERS_SHIFT
;
498 log_msg(VLL_DBG
, msg
, "Received BFD control message", bfd
);
500 if (version
!= BFD_VERSION
) {
501 log_msg(VLL_WARN
, msg
, "Incorrect version", bfd
);
505 /* Technically this should happen after the length check. We don't support
506 * authentication however, so it's simpler to do the check first. */
507 if (flags
& FLAG_AUTH
) {
508 log_msg(VLL_WARN
, msg
, "Authenticated control message with"
509 " authentication disabled", bfd
);
513 if (msg
->length
!= BFD_PACKET_LEN
) {
514 log_msg(VLL_WARN
, msg
, "Unexpected length", bfd
);
515 if (msg
->length
< BFD_PACKET_LEN
) {
521 log_msg(VLL_WARN
, msg
, "Zero multiplier", bfd
);
525 if (flags
& FLAG_MULTIPOINT
) {
526 log_msg(VLL_WARN
, msg
, "Unsupported multipoint flag", bfd
);
531 log_msg(VLL_WARN
, msg
, "NULL my_disc", bfd
);
535 pkt_your_disc
= ntohl(msg
->your_disc
);
537 /* Technically, we should use the your discriminator field to figure
538 * out which 'struct bfd' this packet is destined towards. That way a
539 * bfd session could migrate from one interface to another
540 * transparently. This doesn't fit in with the OVS structure very
541 * well, so in this respect, we are not compliant. */
542 if (pkt_your_disc
!= bfd
->disc
) {
543 log_msg(VLL_WARN
, msg
, "Incorrect your_disc", bfd
);
546 } else if (rmt_state
> STATE_DOWN
) {
547 log_msg(VLL_WARN
, msg
, "Null your_disc", bfd
);
551 bfd
->rmt_disc
= ntohl(msg
->my_disc
);
552 bfd
->rmt_state
= rmt_state
;
553 bfd
->rmt_flags
= flags
;
554 bfd
->rmt_diag
= msg
->vers_diag
& DIAG_MASK
;
556 if (flags
& FLAG_FINAL
&& bfd_in_poll(bfd
)) {
557 bfd
->min_tx
= bfd
->poll_min_tx
;
558 bfd
->min_rx
= bfd
->poll_min_rx
;
559 bfd
->flags
&= ~FLAG_POLL
;
560 log_msg(VLL_INFO
, msg
, "Poll sequence terminated", bfd
);
563 if (flags
& FLAG_POLL
) {
564 /* RFC 5880 Section 6.5
565 * When the other system receives a Poll, it immediately transmits a
566 * BFD Control packet with the Final (F) bit set, independent of any
567 * periodic BFD Control packets it may be sending
568 * (see section 6.8.7). */
569 bfd
->flags
&= ~FLAG_POLL
;
570 bfd
->flags
|= FLAG_FINAL
;
573 rmt_min_rx
= MAX(ntohl(msg
->min_rx
) / 1000, 1);
574 if (bfd
->rmt_min_rx
!= rmt_min_rx
) {
575 bfd
->rmt_min_rx
= rmt_min_rx
;
576 bfd_set_next_tx(bfd
);
577 log_msg(VLL_INFO
, msg
, "New remote min_rx", bfd
);
580 bfd
->rmt_min_tx
= MAX(ntohl(msg
->min_tx
) / 1000, 1);
581 bfd
->detect_time
= bfd_rx_interval(bfd
) * bfd
->mult
+ time_msec();
583 if (bfd
->state
== STATE_ADMIN_DOWN
) {
584 VLOG_DBG_RL(&rl
, "Administratively down, dropping control message.");
588 if (rmt_state
== STATE_ADMIN_DOWN
) {
589 if (bfd
->state
!= STATE_DOWN
) {
590 bfd_set_state(bfd
, STATE_DOWN
, DIAG_RMT_DOWN
);
593 switch (bfd
->state
) {
595 if (rmt_state
== STATE_DOWN
) {
596 bfd_set_state(bfd
, STATE_INIT
, bfd
->diag
);
597 } else if (rmt_state
== STATE_INIT
) {
598 bfd_set_state(bfd
, STATE_UP
, bfd
->diag
);
602 if (rmt_state
> STATE_DOWN
) {
603 bfd_set_state(bfd
, STATE_UP
, bfd
->diag
);
607 if (rmt_state
<= STATE_DOWN
) {
608 bfd_set_state(bfd
, STATE_DOWN
, DIAG_RMT_DOWN
);
609 log_msg(VLL_INFO
, msg
, "Remote signaled STATE_DOWN", bfd
);
612 case STATE_ADMIN_DOWN
:
617 /* XXX: RFC 5880 Section 6.8.6 Demand mode related calculations here. */
622 bfd_in_poll(const struct bfd
*bfd
)
624 return (bfd
->flags
& FLAG_POLL
) != 0;
628 bfd_poll(struct bfd
*bfd
)
630 if (bfd
->state
> STATE_DOWN
&& !bfd_in_poll(bfd
)
631 && !(bfd
->flags
& FLAG_FINAL
)) {
632 bfd
->poll_min_tx
= bfd
->cfg_min_tx
;
633 bfd
->poll_min_rx
= bfd
->cfg_min_rx
;
634 bfd
->flags
|= FLAG_POLL
;
636 VLOG_INFO_RL(&rl
, "%s: Initiating poll sequence", bfd
->name
);
641 bfd_min_tx(const struct bfd
*bfd
)
643 /* RFC 5880 Section 6.8.3
644 * When bfd.SessionState is not Up, the system MUST set
645 * bfd.DesiredMinTxInterval to a value of not less than one second
646 * (1,000,000 microseconds). This is intended to ensure that the
647 * bandwidth consumed by BFD sessions that are not Up is negligible,
648 * particularly in the case where a neighbor may not be running BFD. */
649 return (bfd
->state
== STATE_UP
? bfd
->min_tx
: MAX(bfd
->min_tx
, 1000));
653 bfd_tx_interval(const struct bfd
*bfd
)
655 long long int interval
= bfd_min_tx(bfd
);
656 return MAX(interval
, bfd
->rmt_min_rx
);
660 bfd_rx_interval(const struct bfd
*bfd
)
662 return MAX(bfd
->min_rx
, bfd
->rmt_min_tx
);
666 bfd_set_next_tx(struct bfd
*bfd
)
668 long long int interval
= bfd_tx_interval(bfd
);
669 interval
-= interval
* random_range(26) / 100;
670 bfd
->next_tx
= bfd
->last_tx
+ interval
;
674 bfd_flag_str(enum flags flags
)
676 struct ds ds
= DS_EMPTY_INITIALIZER
;
677 static char flag_str
[128];
683 if (flags
& FLAG_MULTIPOINT
) {
684 ds_put_cstr(&ds
, "multipoint ");
687 if (flags
& FLAG_DEMAND
) {
688 ds_put_cstr(&ds
, "demand ");
691 if (flags
& FLAG_AUTH
) {
692 ds_put_cstr(&ds
, "auth ");
695 if (flags
& FLAG_CTL
) {
696 ds_put_cstr(&ds
, "ctl ");
699 if (flags
& FLAG_FINAL
) {
700 ds_put_cstr(&ds
, "final ");
703 if (flags
& FLAG_POLL
) {
704 ds_put_cstr(&ds
, "poll ");
707 ovs_strlcpy(flag_str
, ds_cstr(&ds
), sizeof flag_str
);
713 bfd_state_str(enum state state
)
716 case STATE_ADMIN_DOWN
: return "admin_down";
717 case STATE_DOWN
: return "down";
718 case STATE_INIT
: return "init";
719 case STATE_UP
: return "up";
720 default: return "invalid";
725 bfd_diag_str(enum diag diag
) {
727 case DIAG_NONE
: return "No Diagnostic";
728 case DIAG_EXPIRED
: return "Control Detection Time Expired";
729 case DIAG_ECHO_FAILED
: return "Echo Function Failed";
730 case DIAG_RMT_DOWN
: return "Neighbor Signaled Session Down";
731 case DIAG_FWD_RESET
: return "Forwarding Plane Reset";
732 case DIAG_PATH_DOWN
: return "Path Down";
733 case DIAG_CPATH_DOWN
: return "Concatenated Path Down";
734 case DIAG_ADMIN_DOWN
: return "Administratively Down";
735 case DIAG_RCPATH_DOWN
: return "Reverse Concatenated Path Down";
736 default: return "Invalid Diagnostic";
741 log_msg(enum vlog_level level
, const struct msg
*p
, const char *message
,
742 const struct bfd
*bfd
)
744 struct ds ds
= DS_EMPTY_INITIALIZER
;
746 if (vlog_should_drop(THIS_MODULE
, level
, &rl
)) {
752 "\n\tvers:%"PRIu8
" diag:\"%s\" state:%s mult:%"PRIu8
755 "\n\tmy_disc:0x%"PRIx32
" your_disc:0x%"PRIx32
756 "\n\tmin_tx:%"PRIu32
"us (%"PRIu32
"ms)"
757 "\n\tmin_rx:%"PRIu32
"us (%"PRIu32
"ms)"
758 "\n\tmin_rx_echo:%"PRIu32
"us (%"PRIu32
"ms)",
759 bfd
->name
, message
, p
->vers_diag
>> VERS_SHIFT
,
760 bfd_diag_str(p
->vers_diag
& DIAG_MASK
),
761 bfd_state_str(p
->flags
& STATE_MASK
),
762 p
->mult
, p
->length
, bfd_flag_str(p
->flags
& FLAGS_MASK
),
763 ntohl(p
->my_disc
), ntohl(p
->your_disc
),
764 ntohl(p
->min_tx
), ntohl(p
->min_tx
) / 1000,
765 ntohl(p
->min_rx
), ntohl(p
->min_rx
) / 1000,
766 ntohl(p
->min_rx_echo
), ntohl(p
->min_rx_echo
) / 1000);
767 bfd_put_details(&ds
, bfd
);
768 VLOG(level
, "%s", ds_cstr(&ds
));
773 bfd_set_state(struct bfd
*bfd
, enum state state
, enum diag diag
)
775 if (diag
== DIAG_NONE
&& bfd
->cpath_down
) {
776 diag
= DIAG_CPATH_DOWN
;
779 if (bfd
->state
!= state
|| bfd
->diag
!= diag
) {
780 if (!VLOG_DROP_INFO(&rl
)) {
781 struct ds ds
= DS_EMPTY_INITIALIZER
;
783 ds_put_format(&ds
, "%s: BFD state change: %s->%s"
784 " \"%s\"->\"%s\".\n",
785 bfd
->name
, bfd_state_str(bfd
->state
),
786 bfd_state_str(state
), bfd_diag_str(bfd
->diag
),
788 bfd_put_details(&ds
, bfd
);
789 VLOG_INFO("%s", ds_cstr(&ds
));
796 if (bfd
->state
<= STATE_DOWN
) {
797 bfd
->rmt_state
= STATE_DOWN
;
798 bfd
->rmt_diag
= DIAG_NONE
;
808 generate_discriminator(void)
812 /* RFC 5880 Section 6.8.1
813 * It SHOULD be set to a random (but still unique) value to improve
814 * security. The value is otherwise outside the scope of this
820 /* 'disc' is by definition random, so there's no reason to waste time
822 disc
= random_uint32();
823 HMAP_FOR_EACH_IN_BUCKET (bfd
, node
, disc
, &all_bfds
) {
824 if (bfd
->disc
== disc
) {
835 bfd_find_by_name(const char *name
)
839 HMAP_FOR_EACH (bfd
, node
, &all_bfds
) {
840 if (!strcmp(bfd
->name
, name
)) {
848 bfd_put_details(struct ds
*ds
, const struct bfd
*bfd
)
850 ds_put_format(ds
, "\tForwarding: %s\n",
851 bfd_forwarding(bfd
) ? "true" : "false");
852 ds_put_format(ds
, "\tDetect Multiplier: %d\n", bfd
->mult
);
853 ds_put_format(ds
, "\tConcatenated Path Down: %s\n",
854 bfd
->cpath_down
? "true" : "false");
855 ds_put_format(ds
, "\tTX Interval: Approx %lldms\n", bfd_tx_interval(bfd
));
856 ds_put_format(ds
, "\tRX Interval: Approx %lldms\n", bfd_rx_interval(bfd
));
857 ds_put_format(ds
, "\tDetect Time: now %+lldms\n",
858 time_msec() - bfd
->detect_time
);
859 ds_put_format(ds
, "\tNext TX Time: now %+lldms\n",
860 time_msec() - bfd
->next_tx
);
861 ds_put_format(ds
, "\tLast TX Time: now %+lldms\n",
862 time_msec() - bfd
->last_tx
);
864 ds_put_cstr(ds
, "\n");
866 ds_put_format(ds
, "\tLocal Flags: %s\n", bfd_flag_str(bfd
->flags
));
867 ds_put_format(ds
, "\tLocal Session State: %s\n",
868 bfd_state_str(bfd
->state
));
869 ds_put_format(ds
, "\tLocal Diagnostic: %s\n", bfd_diag_str(bfd
->diag
));
870 ds_put_format(ds
, "\tLocal Discriminator: 0x%"PRIx32
"\n", bfd
->disc
);
871 ds_put_format(ds
, "\tLocal Minimum TX Interval: %lldms\n",
873 ds_put_format(ds
, "\tLocal Minimum RX Interval: %lldms\n", bfd
->min_rx
);
875 ds_put_cstr(ds
, "\n");
877 ds_put_format(ds
, "\tRemote Flags: %s\n", bfd_flag_str(bfd
->rmt_flags
));
878 ds_put_format(ds
, "\tRemote Session State: %s\n",
879 bfd_state_str(bfd
->rmt_state
));
880 ds_put_format(ds
, "\tRemote Diagnostic: %s\n",
881 bfd_diag_str(bfd
->rmt_diag
));
882 ds_put_format(ds
, "\tRemote Discriminator: 0x%"PRIx32
"\n", bfd
->rmt_disc
);
883 ds_put_format(ds
, "\tRemote Minimum TX Interval: %lldms\n",
885 ds_put_format(ds
, "\tRemote Minimum RX Interval: %lldms\n",
890 bfd_unixctl_show(struct unixctl_conn
*conn
, int argc
, const char *argv
[],
891 void *aux OVS_UNUSED
)
893 struct ds ds
= DS_EMPTY_INITIALIZER
;
897 bfd
= bfd_find_by_name(argv
[1]);
899 unixctl_command_reply_error(conn
, "no such bfd object");
902 bfd_put_details(&ds
, bfd
);
904 HMAP_FOR_EACH (bfd
, node
, &all_bfds
) {
905 ds_put_format(&ds
, "---- %s ----\n", bfd
->name
);
906 bfd_put_details(&ds
, bfd
);
909 unixctl_command_reply(conn
, ds_cstr(&ds
));
915 bfd_unixctl_set_forwarding_override(struct unixctl_conn
*conn
, int argc
,
916 const char *argv
[], void *aux OVS_UNUSED
)
918 const char *forward_str
= argv
[argc
- 1];
919 int forwarding_override
;
922 if (!strcasecmp("true", forward_str
)) {
923 forwarding_override
= 1;
924 } else if (!strcasecmp("false", forward_str
)) {
925 forwarding_override
= 0;
926 } else if (!strcasecmp("normal", forward_str
)) {
927 forwarding_override
= -1;
929 unixctl_command_reply_error(conn
, "unknown fault string");
934 bfd
= bfd_find_by_name(argv
[1]);
936 unixctl_command_reply_error(conn
, "no such BFD object");
939 bfd
->forwarding_override
= forwarding_override
;
941 HMAP_FOR_EACH (bfd
, node
, &all_bfds
) {
942 bfd
->forwarding_override
= forwarding_override
;
946 unixctl_command_reply(conn
, "OK");