2 * Copyright (c) 2010, 2011 Nicira Networks.
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at:
8 * http://www.apache.org/licenses/LICENSE-2.0
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
24 #include "dynamic-string.h"
30 #include "poll-loop.h"
34 VLOG_DEFINE_THIS_MODULE(cfm);
36 #define CCM_OPCODE 1 /* CFM message opcode meaning CCM. */
40 uint32_t seq; /* The sequence number of our last CCM. */
42 uint8_t ccm_interval; /* The CCM transmission interval. */
43 int ccm_interval_ms; /* 'ccm_interval' in milliseconds. */
45 long long ccm_sent; /* The time we last sent a CCM. */
46 long long fault_check; /* The time we last checked for faults. */
48 long long x_recv_time;
52 ccm_interval_to_ms(uint8_t interval)
55 case 0: NOT_REACHED(); /* Explicitly not supported by 802.1ag. */
56 case 1: return 3; /* Not recommended due to timer resolution. */
57 case 2: return 10; /* Not recommended due to timer resolution. */
62 case 7: return 600000;
63 default: NOT_REACHED(); /* Explicitly not supported by 802.1ag. */
70 ms_to_ccm_interval(int interval_ms)
74 for (i = 7; i > 0; i--) {
75 if (ccm_interval_to_ms(i) <= interval_ms) {
83 static struct cfm_internal *
84 cfm_to_internal(const struct cfm *cfm)
86 return CONTAINER_OF(cfm, struct cfm_internal, cfm);
90 hash_mpid(uint8_t mpid)
92 return hash_int(mpid, 0);
96 cfm_is_valid_mpid(uint32_t mpid)
98 /* 802.1ag specification requires MPIDs to be within the range [1, 8191] */
99 return mpid >= 1 && mpid <= 8191;
102 static struct remote_mp *
103 lookup_remote_mp(const struct hmap *hmap, uint16_t mpid)
105 struct remote_mp *rmp;
107 HMAP_FOR_EACH_IN_BUCKET (rmp, node, hash_mpid(mpid), hmap) {
108 if (rmp->mpid == mpid) {
116 /* Allocates a 'cfm' object. This object should have its 'mpid', 'maid',
117 * 'eth_src', and 'interval' filled out. When changes are made to the 'cfm'
118 * object, cfm_configure should be called before using it. */
123 struct cfm_internal *cfmi;
125 cfmi = xzalloc(sizeof *cfmi);
127 cfmi->x_recv_time = LLONG_MIN;
129 hmap_init(&cfm->remote_mps);
134 cfm_destroy(struct cfm *cfm)
136 struct cfm_internal *cfmi = cfm_to_internal(cfm);
137 struct remote_mp *rmp, *rmp_next;
143 HMAP_FOR_EACH_SAFE (rmp, rmp_next, node, &cfm->remote_mps) {
144 hmap_remove(&cfm->remote_mps, &rmp->node);
148 hmap_destroy(&cfm->remote_mps);
152 /* Should be run periodically to update fault statistics messages. */
154 cfm_run(struct cfm *cfm)
156 long long now = time_msec();
157 struct cfm_internal *cfmi = cfm_to_internal(cfm);
158 long long fault_interval;
160 /* According to the 802.1ag specification we should assume every other MP
161 * with the same MAID has the same transmission interval that we have. If
162 * an MP has a different interval, cfm_process_heartbeat will register it
163 * as a fault (likely due to a configuration error). Thus we can check all
164 * MPs at once making this quite a bit simpler.
166 * According to the specification we should check when (ccm_interval_ms *
167 * 3.5)ms have passed. */
168 fault_interval = (cfmi->ccm_interval_ms * 7) / 2;
169 if (now >= cfmi->fault_check + fault_interval) {
171 struct remote_mp *rmp;
173 fault = now < cfmi->x_recv_time + fault_interval;
175 HMAP_FOR_EACH (rmp, node, &cfm->remote_mps) {
176 rmp->fault = rmp->fault || cfmi->fault_check > rmp->recv_time;
177 fault = rmp->fault || fault;
181 cfmi->fault_check = now;
185 /* Should be run periodically to check if the CFM module has a CCM message it
188 cfm_should_send_ccm(struct cfm *cfm)
190 struct cfm_internal *cfmi = cfm_to_internal(cfm);
192 return time_msec() >= cfmi->ccm_sent + cfmi->ccm_interval_ms;
195 /* Composes a CCM message into 'ccm'. Messages generated with this function
196 * should be sent whenever cfm_should_send_ccm() indicates. */
198 cfm_compose_ccm(struct cfm *cfm, struct ccm *ccm)
200 struct cfm_internal *cfmi = cfm_to_internal(cfm);
202 cfmi->ccm_sent = time_msec();
204 ccm->mdlevel_version = 0;
205 ccm->opcode = CCM_OPCODE;
206 ccm->tlv_offset = 70;
207 ccm->seq = htonl(++cfmi->seq);
208 ccm->mpid = htons(cfmi->cfm.mpid);
209 ccm->flags = cfmi->ccm_interval;
210 memcpy(ccm->maid, cfmi->cfm.maid, sizeof ccm->maid);
214 cfm_wait(struct cfm *cfm)
217 struct cfm_internal *cfmi = cfm_to_internal(cfm);
219 wait = MIN(cfmi->ccm_sent + cfmi->ccm_interval_ms,
220 cfmi->fault_check + cfmi->ccm_interval_ms * 4);
221 poll_timer_wait_until(wait);
224 /* Should be called whenever a client of the cfm library changes the internals
225 * of 'cfm'. Returns true if 'cfm' is valid. */
227 cfm_configure(struct cfm *cfm)
229 struct cfm_internal *cfmi;
231 if (!cfm_is_valid_mpid(cfm->mpid) || !cfm->interval) {
235 cfmi = cfm_to_internal(cfm);
236 cfmi->ccm_interval = ms_to_ccm_interval(cfm->interval);
237 cfmi->ccm_interval_ms = ccm_interval_to_ms(cfmi->ccm_interval);
239 /* Force a resend and check in case anything changed. */
241 cfmi->fault_check = 0;
245 /* Given an array of MPIDs, updates the 'remote_mps' map of 'cfm' to reflect
246 * it. Invalid MPIDs are skipped. */
248 cfm_update_remote_mps(struct cfm *cfm, const uint16_t *mpids, size_t n_mpids)
251 struct hmap new_rmps;
252 struct remote_mp *rmp, *rmp_next;
254 hmap_init(&new_rmps);
256 for (i = 0; i < n_mpids; i++) {
257 uint16_t mpid = mpids[i];
259 if (!cfm_is_valid_mpid(mpid)
260 || lookup_remote_mp(&new_rmps, mpid)) {
264 if ((rmp = lookup_remote_mp(&cfm->remote_mps, mpid))) {
265 hmap_remove(&cfm->remote_mps, &rmp->node);
267 rmp = xzalloc(sizeof *rmp);
271 hmap_insert(&new_rmps, &rmp->node, hash_mpid(mpid));
274 hmap_swap(&new_rmps, &cfm->remote_mps);
276 HMAP_FOR_EACH_SAFE (rmp, rmp_next, node, &new_rmps) {
277 hmap_remove(&new_rmps, &rmp->node);
281 hmap_destroy(&new_rmps);
284 /* Finds a 'remote_mp' with 'mpid' in 'cfm'. If no such 'remote_mp' exists
286 const struct remote_mp *
287 cfm_get_remote_mp(const struct cfm *cfm, uint16_t mpid)
289 return lookup_remote_mp(&cfm->remote_mps, mpid);
292 /* Generates 'maid' from 'md_name' and 'ma_name'. A NULL parameter indicates
293 * the default should be used. Returns false if unsuccessful. */
295 cfm_generate_maid(const char *md_name, const char *ma_name,
296 uint8_t maid[CCM_MAID_LEN])
299 size_t md_len, ma_len;
309 memset(maid, 0, CCM_MAID_LEN);
311 md_len = strlen(md_name);
312 ma_len = strlen(ma_name);
314 if (!md_len || !ma_len || md_len + ma_len + 4 > CCM_MAID_LEN) {
318 maid[0] = 4; /* MD name string format. */
319 maid[1] = md_len; /* MD name size. */
320 memcpy(&maid[2], md_name, md_len); /* MD name. */
322 ma_p = maid + 2 + md_len;
323 ma_p[0] = 2; /* MA name string format. */
324 ma_p[1] = ma_len; /* MA name size. */
325 memcpy(&ma_p[2], ma_name, ma_len); /* MA name. */
329 /* Returns true if the CFM library should process packets from 'flow'. */
331 cfm_should_process_flow(const struct flow *flow)
333 return (ntohs(flow->dl_type) == ETH_TYPE_CFM
334 && eth_addr_equals(flow->dl_dst, eth_addr_ccm));
337 /* Updates internal statistics relevant to packet 'p'. Should be called on
338 * every packet whose flow returned true when passed to
339 * cfm_should_process_flow. */
341 cfm_process_heartbeat(struct cfm *cfm, const struct ofpbuf *p)
345 uint8_t ccm_interval;
346 struct remote_mp *rmp;
347 struct eth_header *eth;
349 struct cfm_internal *cfmi = cfm_to_internal(cfm);
350 static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(5, 20);
353 ccm = ofpbuf_at(p, (uint8_t *)p->l3 - (uint8_t *)p->data, CCM_LEN);
356 VLOG_INFO_RL(&rl, "Received an un-parseable 802.1ag CCM heartbeat.");
360 if (ccm->opcode != CCM_OPCODE) {
361 VLOG_INFO_RL(&rl, "Received an unsupported 802.1ag message. "
362 "(opcode %u)", ccm->opcode);
366 if (memcmp(ccm->maid, cfm->maid, sizeof ccm->maid)) {
367 cfmi->x_recv_time = time_msec();
369 VLOG_WARN_RL(&rl, "Received unexpected remote MAID from MAC "
370 ETH_ADDR_FMT, ETH_ADDR_ARGS(eth->eth_src));
372 ccm_mpid = ntohs(ccm->mpid);
373 ccm_interval = ccm->flags & 0x7;
375 rmp = lookup_remote_mp(&cfm->remote_mps, ccm_mpid);
378 rmp->recv_time = time_msec();
379 rmp->fault = ccm_interval != cfmi->ccm_interval;
380 cfm->fault = rmp->fault || cfm->fault;
382 cfmi->x_recv_time = time_msec();
384 VLOG_WARN_RL(&rl, "Received unexpected remote MPID %d from MAC "
385 ETH_ADDR_FMT, ccm_mpid, ETH_ADDR_ARGS(eth->eth_src));
391 cfm_dump_ds(const struct cfm *cfm, struct ds *ds)
393 const struct cfm_internal *cfmi = cfm_to_internal(cfm);
394 long long int now = time_msec();
395 struct remote_mp *rmp;
397 ds_put_format(ds, "MPID %"PRIu16": %s\n", cfm->mpid,
398 cfm->fault ? "fault" : "");
400 ds_put_format(ds, "\tinterval: %dms\n", cfmi->ccm_interval_ms);
401 ds_put_format(ds, "\ttime since CCM tx: %lldms\n", now - cfmi->ccm_sent);
402 ds_put_format(ds, "\ttime since bad CCM rx: %lldms\n",
403 now - cfmi->x_recv_time);
404 ds_put_format(ds, "\ttime since fault check: %lldms\n",
405 now - cfmi->fault_check);
407 ds_put_cstr(ds, "\n");
408 HMAP_FOR_EACH (rmp, node, &cfm->remote_mps) {
409 ds_put_format(ds, "Remote MPID %"PRIu16": %s\n", rmp->mpid,
410 rmp->fault ? "fault" : "");
411 ds_put_format(ds, "\ttime since CCM rx: %lldms\n",
412 time_msec() - rmp->recv_time);