#include <config.h>
#include "cfm.h"
+#include <assert.h>
#include <stdint.h>
#include <stdlib.h>
#include <string.h>
+#include "dynamic-string.h"
#include "flow.h"
#include "hash.h"
#include "hmap.h"
#include "ofpbuf.h"
#include "packets.h"
#include "poll-loop.h"
+#include "timer.h"
#include "timeval.h"
+#include "unixctl.h"
#include "vlog.h"
VLOG_DEFINE_THIS_MODULE(cfm);
-#define CCM_OPCODE 1 /* CFM message opcode meaning CCM. */
-#define DEST_ADDR UINT64_C(0x0180C2000030) /* MD level 0 CCM destination. */
+/* Ethernet destination address of CCM packets. */
+static const uint8_t eth_addr_ccm[6] = { 0x01, 0x80, 0xC2, 0x00, 0x00, 0x30 };
+
+#define ETH_TYPE_CFM 0x8902
+
+/* A 'ccm' represents a Continuity Check Message from the 802.1ag
+ * specification. Continuity Check Messages are broadcast periodically so that
+ * hosts can determine whom they have connectivity to. */
+#define CCM_LEN 74
+#define CCM_MAID_LEN 48
+#define CCM_OPCODE 1 /* CFM message opcode meaning CCM. */
+#define CCM_RDI_MASK 0x80
+struct ccm {
+ uint8_t mdlevel_version; /* MD Level and Version */
+ uint8_t opcode;
+ uint8_t flags;
+ uint8_t tlv_offset;
+ ovs_be32 seq;
+ ovs_be16 mpid;
+ uint8_t maid[CCM_MAID_LEN];
+ uint8_t zero[16]; /* Defined by ITU-T Y.1731 should be zero */
+} __attribute__((packed));
+BUILD_ASSERT_DECL(CCM_LEN == sizeof(struct ccm));
+
+struct cfm {
+ char *name; /* Name of this CFM object. */
+ struct hmap_node hmap_node; /* Node in all_cfms list. */
+
+ uint16_t mpid;
+ bool fault; /* Indicates connectivity fault. */
+ bool recv_fault; /* Indicates an inability to receive CCMs. */
-struct cfm_internal {
- struct cfm cfm;
uint32_t seq; /* The sequence number of our last CCM. */
-
uint8_t ccm_interval; /* The CCM transmission interval. */
int ccm_interval_ms; /* 'ccm_interval' in milliseconds. */
+ uint8_t maid[CCM_MAID_LEN]; /* The MAID of this CFM. */
+
+ struct timer tx_timer; /* Send CCM when expired. */
+ struct timer fault_timer; /* Check for faults when expired. */
+
+ struct hmap remote_mps; /* Expected remote MPs. */
+};
+
+/* Remote MPs represent foreign network entities that are configured to have
+ * the same MAID as this CFM instance. */
+struct remote_mp {
+ uint16_t mpid; /* The Maintenance Point ID of this 'remote_mp'. */
+ struct hmap_node node; /* Node in 'remote_mps' map. */
- long long ccm_sent; /* The time we last sent a CCM. */
- long long fault_check; /* The time we last checked for faults. */
+ bool recv; /* CCM was received since last fault check. */
+ bool fault; /* Indicates a connectivity fault. */
+ bool rdi; /* Remote Defect Indicator. Indicates remote_mp isn't
+ receiving CCMs that it's expecting to. */
};
+static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(5, 20);
+static struct hmap all_cfms = HMAP_INITIALIZER(&all_cfms);
+
+static void cfm_unixctl_show(struct unixctl_conn *, const char *args,
+ void *aux);
+
+static void
+cfm_generate_maid(struct cfm *cfm)
+{
+ const char *ovs_md_name = "ovs_md";
+ const char *ovs_ma_name = "ovs_ma";
+ uint8_t *ma_p;
+ size_t md_len, ma_len;
+
+ memset(cfm->maid, 0, CCM_MAID_LEN);
+
+ md_len = strlen(ovs_md_name);
+ ma_len = strlen(ovs_ma_name);
+
+ assert(md_len && ma_len && md_len + ma_len + 4 <= CCM_MAID_LEN);
+
+ cfm->maid[0] = 4; /* MD name string format. */
+ cfm->maid[1] = md_len; /* MD name size. */
+ memcpy(&cfm->maid[2], ovs_md_name, md_len); /* MD name. */
+
+ ma_p = cfm->maid + 2 + md_len;
+ ma_p[0] = 2; /* MA name string format. */
+ ma_p[1] = ma_len; /* MA name size. */
+ memcpy(&ma_p[2], ovs_ma_name, ma_len); /* MA name. */
+}
+
static int
ccm_interval_to_ms(uint8_t interval)
{
NOT_REACHED();
}
+static long long int
+cfm_fault_interval(struct cfm *cfm)
+{
+ /* According to the 802.1ag specification we should assume every other MP
+ * with the same MAID has the same transmission interval that we have. If
+ * an MP has a different interval, cfm_process_heartbeat will register it
+ * as a fault (likely due to a configuration error). Thus we can check all
+ * MPs at once making this quite a bit simpler.
+ *
+ * According to the specification we should check when (ccm_interval_ms *
+ * 3.5)ms have passed. */
+ return (cfm->ccm_interval_ms * 7) / 2;
+}
+
static uint8_t
ms_to_ccm_interval(int interval_ms)
{
return 1;
}
-static struct cfm_internal *
-cfm_to_internal(struct cfm *cfm)
-{
- return CONTAINER_OF(cfm, struct cfm_internal, cfm);
-}
-
static uint32_t
hash_mpid(uint8_t mpid)
{
return NULL;
}
-static struct ofpbuf *
-compose_ccm(struct cfm_internal *cfmi)
+void
+cfm_init(void)
{
- struct ccm *ccm;
- struct ofpbuf *packet;
- struct eth_header *eth;
-
- packet = ofpbuf_new(ETH_HEADER_LEN + CCM_LEN + 2);
-
- ofpbuf_reserve(packet, 2);
-
- eth = ofpbuf_put_zeros(packet, ETH_HEADER_LEN);
- ccm = ofpbuf_put_zeros(packet, CCM_LEN);
-
- eth_addr_from_uint64(DEST_ADDR, eth->eth_dst);
- memcpy(eth->eth_src, cfmi->cfm.eth_src, sizeof eth->eth_src);
- eth->eth_type = htons(ETH_TYPE_CFM);
-
- ccm->mdlevel_version = 0;
- ccm->opcode = CCM_OPCODE;
- ccm->tlv_offset = 70;
- ccm->seq = htonl(++cfmi->seq);
- ccm->mpid = htons(cfmi->cfm.mpid);
- ccm->flags = cfmi->ccm_interval;
- memcpy(ccm->maid, cfmi->cfm.maid, sizeof ccm->maid);
- return packet;
+ unixctl_command_register("cfm/show", cfm_unixctl_show, NULL);
}
-/* Allocates a 'cfm' object. This object should have its 'mpid', 'maid',
- * 'eth_src', and 'interval' filled out. When changes are made to the 'cfm'
- * object, cfm_configure should be called before using it. */
+/* Allocates a 'cfm' object called 'name'. 'cfm' should be initialized by
+ * cfm_configure() before use. */
struct cfm *
-cfm_create(void)
+cfm_create(const char *name)
{
struct cfm *cfm;
- struct cfm_internal *cfmi;
-
- cfmi = xzalloc(sizeof *cfmi);
- cfm = &cfmi->cfm;
+ cfm = xzalloc(sizeof *cfm);
+ cfm->name = xstrdup(name);
hmap_init(&cfm->remote_mps);
- hmap_init(&cfm->x_remote_mps);
- hmap_init(&cfm->x_remote_maids);
+ cfm_generate_maid(cfm);
+ hmap_insert(&all_cfms, &cfm->hmap_node, hash_string(cfm->name, 0));
return cfm;
}
cfm_destroy(struct cfm *cfm)
{
struct remote_mp *rmp, *rmp_next;
- struct remote_maid *rmaid, *rmaid_next;
if (!cfm) {
return;
free(rmp);
}
- HMAP_FOR_EACH_SAFE (rmp, rmp_next, node, &cfm->x_remote_mps) {
- hmap_remove(&cfm->x_remote_mps, &rmp->node);
- free(rmp);
- }
-
- HMAP_FOR_EACH_SAFE (rmaid, rmaid_next, node, &cfm->x_remote_maids) {
- hmap_remove(&cfm->x_remote_maids, &rmaid->node);
- free(rmaid);
- }
-
hmap_destroy(&cfm->remote_mps);
- hmap_destroy(&cfm->x_remote_mps);
- hmap_destroy(&cfm->x_remote_maids);
- free(cfm_to_internal(cfm));
+ hmap_remove(&all_cfms, &cfm->hmap_node);
+ free(cfm->name);
+ free(cfm);
}
-/* Should be run periodically to update fault statistics and generate CCM
- * messages. If necessary, returns a packet which the caller is responsible
- * for sending, un-initing, and deallocating. Otherwise returns NULL. */
-struct ofpbuf *
+/* Should be run periodically to update fault statistics messages. */
+void
cfm_run(struct cfm *cfm)
{
- long long now = time_msec();
- struct cfm_internal *cfmi = cfm_to_internal(cfm);
-
- /* According to the 802.1ag specification we should assume every other MP
- * with the same MAID has the same transmission interval that we have. If
- * an MP has a different interval, cfm_process_heartbeat will register it
- * as a fault (likely due to a configuration error). Thus we can check all
- * MPs at once making this quite a bit simpler.
- *
- * According to the specification we should check when (ccm_interval_ms *
- * 3.5)ms have passed. We changed the multiplier to 4 to avoid messy
- * floating point arithmetic and add a bit of wiggle room. */
- if (now >= cfmi->fault_check + cfmi->ccm_interval_ms * 4) {
- bool fault;
- struct remote_mp *rmp, *rmp_next;
- struct remote_maid *rmaid, *rmaid_next;
-
- fault = false;
+ if (timer_expired(&cfm->fault_timer)) {
+ long long int interval = cfm_fault_interval(cfm);
+ struct remote_mp *rmp;
+ cfm->fault = false;
+ cfm->recv_fault = false;
HMAP_FOR_EACH (rmp, node, &cfm->remote_mps) {
- rmp->fault = rmp->fault || cfmi->fault_check > rmp->recv_time;
- fault = rmp->fault || fault;
- }
-
- HMAP_FOR_EACH_SAFE (rmp, rmp_next, node, &cfm->x_remote_mps) {
- if (cfmi->fault_check > rmp->recv_time) {
- hmap_remove(&cfm->x_remote_mps, &rmp->node);
- free(rmp);
+ rmp->fault = !rmp->recv;
+ rmp->recv = false;
+
+ if (rmp->fault) {
+ cfm->recv_fault = true;
+ VLOG_DBG("No CCM from RMP %"PRIu16" in the last %lldms",
+ rmp->mpid, interval);
+ } else if (rmp->rdi) {
+ cfm->fault = true;
+ VLOG_DBG("RDI bit flagged from RMP %"PRIu16, rmp->mpid);
}
}
- HMAP_FOR_EACH_SAFE (rmaid, rmaid_next, node, &cfm->x_remote_maids) {
- if (cfmi->fault_check > rmaid->recv_time) {
- hmap_remove(&cfm->x_remote_maids, &rmaid->node);
- free(rmaid);
- }
+ if (cfm->recv_fault) {
+ cfm->fault = true;
+ } else {
+ VLOG_DBG("All RMPs received CCMs in the last %lldms", interval);
}
- fault = (fault || !hmap_is_empty(&cfm->x_remote_mps)
- || !hmap_is_empty(&cfm->x_remote_maids));
-
- cfm->fault = fault;
- cfmi->fault_check = now;
+ timer_set_duration(&cfm->fault_timer, interval);
}
+}
- if (now >= cfmi->ccm_sent + cfmi->ccm_interval_ms) {
- cfmi->ccm_sent = now;
- return compose_ccm(cfmi);
- }
+/* Should be run periodically to check if the CFM module has a CCM message it
+ * wishes to send. */
+bool
+cfm_should_send_ccm(struct cfm *cfm)
+{
+ return timer_expired(&cfm->tx_timer);
+}
- return NULL;
+/* Composes a CCM message into 'packet'. Messages generated with this function
+ * should be sent whenever cfm_should_send_ccm() indicates. */
+void
+cfm_compose_ccm(struct cfm *cfm, struct ofpbuf *packet,
+ uint8_t eth_src[ETH_ADDR_LEN])
+{
+ struct ccm *ccm;
+
+ timer_set_duration(&cfm->tx_timer, cfm->ccm_interval_ms);
+
+ ccm = eth_compose(packet, eth_addr_ccm, eth_src, ETH_TYPE_CFM,
+ sizeof *ccm);
+ ccm->mdlevel_version = 0;
+ ccm->opcode = CCM_OPCODE;
+ ccm->tlv_offset = 70;
+ ccm->seq = htonl(++cfm->seq);
+ ccm->mpid = htons(cfm->mpid);
+ ccm->flags = cfm->ccm_interval;
+ memcpy(ccm->maid, cfm->maid, sizeof ccm->maid);
+
+ if (cfm->recv_fault) {
+ ccm->flags |= CCM_RDI_MASK;
+ }
}
void
cfm_wait(struct cfm *cfm)
{
- long long wait;
- struct cfm_internal *cfmi = cfm_to_internal(cfm);
- wait = MIN(cfmi->ccm_sent + cfmi->ccm_interval_ms,
- cfmi->fault_check + cfmi->ccm_interval_ms * 4);
- poll_timer_wait_until(wait);
+ timer_wait(&cfm->tx_timer);
+ timer_wait(&cfm->fault_timer);
}
-/* Should be called whenever a client of the cfm library changes the internals
- * of 'cfm'. Returns true if 'cfm' is valid. */
+/* Configures 'cfm' with settings from 's'. */
bool
-cfm_configure(struct cfm *cfm)
+cfm_configure(struct cfm *cfm, const struct cfm_settings *s)
{
- struct cfm_internal *cfmi;
+ size_t i;
+ uint8_t interval;
+ struct hmap new_rmps;
+ struct remote_mp *rmp, *rmp_next;
- if (!cfm_is_valid_mpid(cfm->mpid) || !cfm->interval) {
+ if (!cfm_is_valid_mpid(s->mpid) || s->interval <= 0
+ || s->n_remote_mpids <= 0) {
return false;
}
- cfmi = cfm_to_internal(cfm);
- cfmi->ccm_interval = ms_to_ccm_interval(cfm->interval);
- cfmi->ccm_interval_ms = ccm_interval_to_ms(cfmi->ccm_interval);
+ cfm->mpid = s->mpid;
+ interval = ms_to_ccm_interval(s->interval);
- /* Force a resend and check in case anything changed. */
- cfmi->ccm_sent = 0;
- cfmi->fault_check = 0;
- return true;
-}
+ if (interval != cfm->ccm_interval) {
+ cfm->ccm_interval = interval;
+ cfm->ccm_interval_ms = ccm_interval_to_ms(interval);
-/* Given an array of MPIDs, updates the 'remote_mps' map of 'cfm' to reflect
- * it. Invalid MPIDs are skipped. */
-void
-cfm_update_remote_mps(struct cfm *cfm, const uint16_t *mpids, size_t n_mpids)
-{
- size_t i;
- struct hmap new_rmps;
- struct remote_mp *rmp, *rmp_next;
+ timer_set_expired(&cfm->tx_timer);
+ timer_set_duration(&cfm->fault_timer, cfm_fault_interval(cfm));
+ }
hmap_init(&new_rmps);
-
- for (i = 0; i < n_mpids; i++) {
- uint16_t mpid = mpids[i];
+ for (i = 0; i < s->n_remote_mpids; i++) {
+ uint16_t mpid = s->remote_mpids[i];
if (!cfm_is_valid_mpid(mpid)
|| lookup_remote_mp(&new_rmps, mpid)) {
if ((rmp = lookup_remote_mp(&cfm->remote_mps, mpid))) {
hmap_remove(&cfm->remote_mps, &rmp->node);
- } else if ((rmp = lookup_remote_mp(&cfm->x_remote_mps, mpid))) {
- hmap_remove(&cfm->x_remote_mps, &rmp->node);
} else {
rmp = xzalloc(sizeof *rmp);
rmp->mpid = mpid;
}
hmap_swap(&new_rmps, &cfm->remote_mps);
-
HMAP_FOR_EACH_SAFE (rmp, rmp_next, node, &new_rmps) {
hmap_remove(&new_rmps, &rmp->node);
free(rmp);
}
-
hmap_destroy(&new_rmps);
-}
-
-/* Finds a 'remote_mp' with 'mpid' in 'cfm'. If no such 'remote_mp' exists
- * returns NULL. */
-const struct remote_mp *
-cfm_get_remote_mp(const struct cfm *cfm, uint16_t mpid)
-{
- return lookup_remote_mp(&cfm->remote_mps, mpid);
-}
-
-/* Generates 'maid' from 'md_name' and 'ma_name'. A NULL parameter indicates
- * the default should be used. Returns false if unsuccessful. */
-bool
-cfm_generate_maid(const char *md_name, const char *ma_name,
- uint8_t maid[CCM_MAID_LEN])
-{
- uint8_t *ma_p;
- size_t md_len, ma_len;
-
- if (!md_name) {
- md_name = "ovs";
- }
-
- if (!ma_name) {
- ma_name = "ovs";
- }
-
- memset(maid, 0, CCM_MAID_LEN);
-
- md_len = strlen(md_name);
- ma_len = strlen(ma_name);
-
- if (!md_len || !ma_len || md_len + ma_len + 4 > CCM_MAID_LEN) {
- return false;
- }
- maid[0] = 4; /* MD name string format. */
- maid[1] = md_len; /* MD name size. */
- memcpy(&maid[2], md_name, md_len); /* MD name. */
-
- ma_p = maid + 2 + md_len;
- ma_p[0] = 2; /* MA name string format. */
- ma_p[1] = ma_len; /* MA name size. */
- memcpy(&ma_p[2], ma_name, ma_len); /* MA name. */
return true;
}
cfm_should_process_flow(const struct flow *flow)
{
return (ntohs(flow->dl_type) == ETH_TYPE_CFM
- && eth_addr_to_uint64(flow->dl_dst) == DEST_ADDR);
+ && eth_addr_equals(flow->dl_dst, eth_addr_ccm));
}
/* Updates internal statistics relevant to packet 'p'. Should be called on
cfm_process_heartbeat(struct cfm *cfm, const struct ofpbuf *p)
{
struct ccm *ccm;
+ bool ccm_rdi;
uint16_t ccm_mpid;
- uint32_t ccm_seq;
uint8_t ccm_interval;
struct remote_mp *rmp;
+ struct eth_header *eth;
- struct cfm_internal *cfmi = cfm_to_internal(cfm);
- static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(5, 20);
-
+ eth = p->l2;
ccm = ofpbuf_at(p, (uint8_t *)p->l3 - (uint8_t *)p->data, CCM_LEN);
if (!ccm) {
return;
}
+ /* According to the 802.1ag specification, reception of a CCM with an
+ * incorrect ccm_interval, unexpected MAID, or unexpected MPID should
+ * trigger a fault. We ignore this requirement for several reasons.
+ *
+ * Faults can cause a controller or Open vSwitch to make potentially
+ * expensive changes to the network topology. It seems prudent to trigger
+ * them judiciously, especially when CFM is used to check slave status of
+ * bonds. Furthermore, faults can be maliciously triggered by crafting
+ * invalid CCMs. */
if (memcmp(ccm->maid, cfm->maid, sizeof ccm->maid)) {
- uint32_t hash;
- struct remote_maid *rmaid;
-
- hash = hash_bytes(ccm->maid, sizeof ccm->maid, 0);
-
- HMAP_FOR_EACH_IN_BUCKET (rmaid, node, hash, &cfm->x_remote_maids) {
- if (memcmp(rmaid->maid, ccm->maid, sizeof rmaid->maid) == 0) {
- rmaid->recv_time = time_msec();
- return;
+ VLOG_WARN_RL(&rl, "Received unexpected remote MAID from MAC "
+ ETH_ADDR_FMT, ETH_ADDR_ARGS(eth->eth_src));
+ } else {
+ ccm_mpid = ntohs(ccm->mpid);
+ ccm_interval = ccm->flags & 0x7;
+ ccm_rdi = ccm->flags & CCM_RDI_MASK;
+
+ rmp = lookup_remote_mp(&cfm->remote_mps, ccm_mpid);
+
+ if (rmp) {
+ rmp->recv = true;
+ rmp->rdi = ccm_rdi;
+
+ if (ccm_interval != cfm->ccm_interval) {
+ VLOG_WARN_RL(&rl, "received a CCM with an invalid interval"
+ " (%"PRIu8") from RMP %"PRIu16, ccm_interval,
+ rmp->mpid);
}
+ } else {
+ VLOG_WARN_RL(&rl, "Received unexpected remote MPID %d from MAC "
+ ETH_ADDR_FMT, ccm_mpid, ETH_ADDR_ARGS(eth->eth_src));
}
- rmaid = xzalloc(sizeof *rmaid);
- rmaid->recv_time = time_msec();
- memcpy(rmaid->maid, ccm->maid, sizeof rmaid->maid);
- hmap_insert(&cfm->x_remote_maids, &rmaid->node, hash);
- return;
+ VLOG_DBG("Received CCM (mpid %"PRIu16") (interval %"PRIu8") (RDI %s)",
+ ccm_mpid, ccm_interval, ccm_rdi ? "true" : "false");
}
+}
+
+/* Gets the fault status of 'cfm'. Returns true when 'cfm' has detected
+ * connectivity problems, false otherwise. */
+bool
+cfm_get_fault(const struct cfm *cfm)
+{
+ return cfm->fault;
+}
+
+static struct cfm *
+cfm_find(const char *name)
+{
+ struct cfm *cfm;
- ccm_mpid = ntohs(ccm->mpid);
- ccm_seq = ntohl(ccm->seq);
- ccm_interval = ccm->flags & 0x7;
+ HMAP_FOR_EACH_WITH_HASH (cfm, hmap_node, hash_string(name, 0), &all_cfms) {
+ if (!strcmp(cfm->name, name)) {
+ return cfm;
+ }
+ }
+ return NULL;
+}
- rmp = lookup_remote_mp(&cfm->remote_mps, ccm_mpid);
+static void
+cfm_unixctl_show(struct unixctl_conn *conn,
+ const char *args, void *aux OVS_UNUSED)
+{
+ struct ds ds = DS_EMPTY_INITIALIZER;
+ const struct cfm *cfm;
+ struct remote_mp *rmp;
- if (!rmp) {
- rmp = lookup_remote_mp(&cfm->x_remote_mps, ccm_mpid);
+ cfm = cfm_find(args);
+ if (!cfm) {
+ unixctl_command_reply(conn, 501, "no such CFM object");
+ return;
}
- if (!rmp) {
- rmp = xzalloc(sizeof *rmp);
- rmp->mpid = ccm_mpid;
- hmap_insert(&cfm->x_remote_mps, &rmp->node, hash_mpid(ccm_mpid));
- cfm->fault = true;
+ ds_put_format(&ds, "MPID %"PRIu16":%s%s\n", cfm->mpid,
+ cfm->fault ? " fault" : "",
+ cfm->recv_fault ? " recv_fault" : "");
+
+ ds_put_format(&ds, "\tinterval: %dms\n", cfm->ccm_interval_ms);
+ ds_put_format(&ds, "\tnext CCM tx: %lldms\n",
+ timer_msecs_until_expired(&cfm->tx_timer));
+ ds_put_format(&ds, "\tnext fault check: %lldms\n",
+ timer_msecs_until_expired(&cfm->fault_timer));
+
+ ds_put_cstr(&ds, "\n");
+ HMAP_FOR_EACH (rmp, node, &cfm->remote_mps) {
+ ds_put_format(&ds, "Remote MPID %"PRIu16": %s\n", rmp->mpid,
+ rmp->fault ? "fault" : "");
+ ds_put_format(&ds, "\trecv since check: %s",
+ rmp->recv ? "true" : "false");
}
- rmp->recv_time = time_msec();
- rmp->fault = ccm_interval != cfmi->ccm_interval;
+ unixctl_command_reply(conn, 200, ds_cstr(&ds));
+ ds_destroy(&ds);
}
git://git.onelab.eu / sliver-openvswitch.git / blobdiff