#include "hash.h"
#include "hmap.h"
#include "list.h"
+#include "netdev.h"
#include "netlink.h"
#include "odp-util.h"
#include "ofpbuf.h"
#include "random.h"
#include "smap.h"
#include "timeval.h"
+#include "unaligned.h"
#include "unixctl.h"
#include "util.h"
#include "vlog.h"
bool cpath_down; /* Concatenated Path Down. */
uint8_t mult; /* bfd.DetectMult. */
+ struct netdev *netdev;
+ uint64_t rx_packets; /* Packets received by 'netdev'. */
+
enum state state; /* bfd.SessionState. */
enum state rmt_state; /* bfd.RemoteSessionState. */
atomic_bool check_tnl_key; /* Verify tunnel key of inbound packets? */
atomic_int ref_cnt;
+
+ /* When forward_if_rx is true, bfd_forwarding() will return
+ * true as long as there are incoming packets received.
+ * Note, forwarding_override still has higher priority. */
+ bool forwarding_if_rx;
+ long long int forwarding_if_rx_detect_time;
+
+ /* BFD decay related variables. */
+ bool in_decay; /* True when bfd is in decay. */
+ int decay_min_rx; /* min_rx is set to decay_min_rx when */
+ /* in decay. */
+ int decay_rx_ctl; /* Count bfd packets received within decay */
+ /* detect interval. */
+ uint64_t decay_rx_packets; /* Packets received by 'netdev'. */
+ long long int decay_detect_time; /* Decay detection time. */
};
static struct ovs_mutex mutex = OVS_MUTEX_INITIALIZER;
static uint32_t generate_discriminator(void) OVS_REQUIRES(mutex);
static void bfd_put_details(struct ds *, const struct bfd *)
OVS_REQUIRES(mutex);
+static uint64_t bfd_rx_packets(const struct bfd *) OVS_REQUIRES(mutex);
+static void bfd_try_decay(struct bfd *) OVS_REQUIRES(mutex);
+static void bfd_decay_update(struct bfd *) OVS_REQUIRES(mutex);
+static void bfd_check_rx(struct bfd *) OVS_REQUIRES(mutex);
+static void bfd_forwarding_if_rx_update(struct bfd *) OVS_REQUIRES(mutex);
static void bfd_unixctl_show(struct unixctl_conn *, int argc,
const char *argv[], void *aux OVS_UNUSED);
static void bfd_unixctl_set_forwarding_override(struct unixctl_conn *,
* handle for the session, or NULL if BFD is not enabled according to 'cfg'.
* Also returns NULL if cfg is NULL. */
struct bfd *
-bfd_configure(struct bfd *bfd, const char *name, const struct smap *cfg)
- OVS_EXCLUDED(mutex)
+bfd_configure(struct bfd *bfd, const char *name, const struct smap *cfg,
+ struct netdev *netdev) OVS_EXCLUDED(mutex)
{
static struct ovsthread_once once = OVSTHREAD_ONCE_INITIALIZER;
static atomic_uint16_t udp_src = ATOMIC_VAR_INIT(0);
+ int decay_min_rx;
long long int min_tx, min_rx;
bool need_poll = false;
- bool cpath_down;
+ bool cfg_min_rx_changed = false;
+ bool cpath_down, forwarding_if_rx;
const char *hwaddr;
uint8_t ea[ETH_ADDR_LEN];
bfd->min_tx = 1000;
bfd->mult = 3;
atomic_init(&bfd->ref_cnt, 1);
+ bfd->netdev = netdev_ref(netdev);
+ bfd->rx_packets = bfd_rx_packets(bfd);
+ bfd->in_decay = false;
/* RFC 5881 section 4
* The source port MUST be in the range 49152 through 65535. The same
|| (!bfd_in_poll(bfd) && bfd->cfg_min_rx > bfd->min_rx)) {
bfd->min_rx = bfd->cfg_min_rx;
}
+ cfg_min_rx_changed = true;
+ need_poll = true;
+ }
+
+ decay_min_rx = smap_get_int(cfg, "decay_min_rx", 0);
+ if (bfd->decay_min_rx != decay_min_rx || cfg_min_rx_changed) {
+ if (decay_min_rx > 0 && decay_min_rx < bfd->cfg_min_rx) {
+ VLOG_WARN("%s: decay_min_rx cannot be less than %lld ms",
+ bfd->name, bfd->cfg_min_rx);
+ bfd->decay_min_rx = 0;
+ } else {
+ bfd->decay_min_rx = decay_min_rx;
+ }
+ /* Resets decay. */
+ bfd->in_decay = false;
+ bfd_decay_update(bfd);
need_poll = true;
}
bfd->eth_dst_set = false;
}
+ forwarding_if_rx = smap_get_bool(cfg, "forwarding_if_rx", false);
+ if (bfd->forwarding_if_rx != forwarding_if_rx) {
+ bfd->forwarding_if_rx = forwarding_if_rx;
+ if (bfd->state == STATE_UP && bfd->forwarding_if_rx) {
+ bfd_forwarding_if_rx_update(bfd);
+ } else {
+ bfd->forwarding_if_rx_detect_time = 0;
+ }
+ }
+
if (need_poll) {
bfd_poll(bfd);
}
if (orig == 1) {
ovs_mutex_lock(&mutex);
hmap_remove(all_bfds, &bfd->node);
+ netdev_close(bfd->netdev);
free(bfd->name);
free(bfd);
ovs_mutex_unlock(&mutex);
void
bfd_wait(const struct bfd *bfd) OVS_EXCLUDED(mutex)
{
- ovs_mutex_lock(&mutex);
- if (bfd->flags & FLAG_FINAL) {
- poll_immediate_wake();
+ poll_timer_wait_until(bfd_wake_time(bfd));
+}
+
+/* Returns the next wake up time. */
+long long int
+bfd_wake_time(const struct bfd *bfd) OVS_EXCLUDED(mutex)
+{
+ long long int retval;
+
+ if (!bfd) {
+ return LLONG_MAX;
}
- poll_timer_wait_until(bfd->next_tx);
- if (bfd->state > STATE_DOWN) {
- poll_timer_wait_until(bfd->detect_time);
+ ovs_mutex_lock(&mutex);
+ if (bfd->flags & FLAG_FINAL) {
+ retval = 0;
+ } else {
+ retval = bfd->next_tx;
+ if (bfd->state > STATE_DOWN) {
+ retval = MIN(bfd->detect_time, retval);
+ }
}
ovs_mutex_unlock(&mutex);
+ return retval;
}
void
bfd_run(struct bfd *bfd) OVS_EXCLUDED(mutex)
{
+ long long int now;
+ bool old_in_decay;
+
ovs_mutex_lock(&mutex);
- if (bfd->state > STATE_DOWN && time_msec() >= bfd->detect_time) {
+ now = time_msec();
+ old_in_decay = bfd->in_decay;
+
+ if (bfd->state > STATE_DOWN && now >= bfd->detect_time) {
bfd_set_state(bfd, STATE_DOWN, DIAG_EXPIRED);
}
- if (bfd->min_tx != bfd->cfg_min_tx || bfd->min_rx != bfd->cfg_min_rx) {
+ /* Decay may only happen when state is STATE_UP, bfd->decay_min_rx is
+ * configured, and decay_detect_time is reached. */
+ if (bfd->state == STATE_UP && bfd->decay_min_rx > 0
+ && now >= bfd->decay_detect_time) {
+ bfd_try_decay(bfd);
+ }
+
+ /* Always checks the reception of any packet. */
+ bfd_check_rx(bfd);
+
+ if (bfd->min_tx != bfd->cfg_min_tx
+ || (bfd->min_rx != bfd->cfg_min_rx && bfd->min_rx != bfd->decay_min_rx)
+ || bfd->in_decay != old_in_decay) {
bfd_poll(bfd);
}
ovs_mutex_unlock(&mutex);
ip->ip_ttl = MAXTTL;
ip->ip_tos = IPTOS_LOWDELAY | IPTOS_THROUGHPUT;
ip->ip_proto = IPPROTO_UDP;
- ip->ip_src = htonl(0xA9FE0100); /* 169.254.1.0 Link Local. */
- ip->ip_dst = htonl(0xA9FE0101); /* 169.254.1.1 Link Local. */
+ /* Use link local addresses: */
+ put_16aligned_be32(&ip->ip_src, htonl(0xA9FE0100)); /* 169.254.1.0. */
+ put_16aligned_be32(&ip->ip_dst, htonl(0xA9FE0101)); /* 169.254.1.1. */
ip->ip_csum = csum(ip, sizeof *ip);
udp = ofpbuf_put_zeros(p, sizeof *udp);
}
bool
-bfd_should_process_flow(const struct bfd *bfd, const struct flow *flow,
+bfd_should_process_flow(const struct bfd *bfd_, const struct flow *flow,
struct flow_wildcards *wc)
{
+ struct bfd *bfd = CONST_CAST(struct bfd *, bfd_);
bool check_tnl_key;
+
memset(&wc->masks.dl_dst, 0xff, sizeof wc->masks.dl_dst);
if (bfd->eth_dst_set && memcmp(bfd->eth_dst, flow->dl_dst, ETH_ADDR_LEN)) {
return false;
/* This function is designed to follow section RFC 5880 6.8.6 closely. */
ovs_mutex_lock(&mutex);
+ /* Increments the decay rx counter. */
+ bfd->decay_rx_ctl++;
+
if (flow->nw_ttl != 255) {
/* XXX Should drop in the kernel to prevent DOS. */
goto out;
msg = ofpbuf_at(p, (uint8_t *)p->l7 - (uint8_t *)p->data, BFD_PACKET_LEN);
if (!msg) {
- VLOG_INFO_RL(&rl, "%s: Received unparseable BFD control message.",
- bfd->name);
+ VLOG_INFO_RL(&rl, "%s: Received too-short BFD control message (only "
+ "%td bytes long, at least %d required).",
+ bfd->name, (uint8_t *) ofpbuf_tail(p) - (uint8_t *) p->l7,
+ BFD_PACKET_LEN);
goto out;
}
out:
ovs_mutex_unlock(&mutex);
}
+
+/* Must be called when the netdev owned by 'bfd' should change. */
+void
+bfd_set_netdev(struct bfd *bfd, const struct netdev *netdev)
+ OVS_EXCLUDED(mutex)
+{
+ ovs_mutex_lock(&mutex);
+ if (bfd->netdev != netdev) {
+ netdev_close(bfd->netdev);
+ bfd->netdev = netdev_ref(netdev);
+ if (bfd->decay_min_rx && bfd->state == STATE_UP) {
+ bfd_decay_update(bfd);
+ }
+ if (bfd->forwarding_if_rx && bfd->state == STATE_UP) {
+ bfd_forwarding_if_rx_update(bfd);
+ }
+ bfd->rx_packets = bfd_rx_packets(bfd);
+ }
+ ovs_mutex_unlock(&mutex);
+}
+
\f
static bool
bfd_forwarding__(const struct bfd *bfd) OVS_REQUIRES(mutex)
{
+ long long int time;
+
if (bfd->forwarding_override != -1) {
return bfd->forwarding_override == 1;
}
- return bfd->state == STATE_UP
- && bfd->rmt_diag != DIAG_PATH_DOWN
- && bfd->rmt_diag != DIAG_CPATH_DOWN
- && bfd->rmt_diag != DIAG_RCPATH_DOWN;
+ time = bfd->forwarding_if_rx_detect_time;
+ return (bfd->state == STATE_UP
+ || (bfd->forwarding_if_rx && time > time_msec()))
+ && bfd->rmt_diag != DIAG_PATH_DOWN
+ && bfd->rmt_diag != DIAG_CPATH_DOWN
+ && bfd->rmt_diag != DIAG_RCPATH_DOWN;
}
/* Helpers. */
if (bfd->state > STATE_DOWN && !bfd_in_poll(bfd)
&& !(bfd->flags & FLAG_FINAL)) {
bfd->poll_min_tx = bfd->cfg_min_tx;
- bfd->poll_min_rx = bfd->cfg_min_rx;
+ bfd->poll_min_rx = bfd->in_decay ? bfd->decay_min_rx : bfd->cfg_min_rx;
bfd->flags |= FLAG_POLL;
bfd->next_tx = 0;
VLOG_INFO_RL(&rl, "%s: Initiating poll sequence", bfd->name);
bfd->rmt_flags = 0;
bfd->rmt_disc = 0;
bfd->rmt_min_tx = 0;
+ /* Resets the min_rx if in_decay. */
+ if (bfd->in_decay) {
+ bfd->min_rx = bfd->cfg_min_rx;
+ bfd->in_decay = false;
+ }
}
+ /* Resets the decay when state changes to STATE_UP
+ * and decay_min_rx is configured. */
+ if (bfd->state == STATE_UP && bfd->decay_min_rx) {
+ bfd_decay_update(bfd);
+ }
+ }
+}
+
+static uint64_t
+bfd_rx_packets(const struct bfd *bfd) OVS_REQUIRES(mutex)
+{
+ struct netdev_stats stats;
+
+ if (!netdev_get_stats(bfd->netdev, &stats)) {
+ return stats.rx_packets;
+ } else {
+ return 0;
}
}
+/* Decays the bfd->min_rx to bfd->decay_min_rx when 'diff' is less than
+ * the 'expect' value. */
+static void
+bfd_try_decay(struct bfd *bfd) OVS_REQUIRES(mutex)
+{
+ int64_t diff, expect;
+
+ /* The 'diff' is the difference between current interface rx_packets
+ * stats and last-time check. The 'expect' is the recorded number of
+ * bfd control packets received within an approximately decay_min_rx
+ * (2000 ms if decay_min_rx is less than 2000 ms) interval.
+ *
+ * Since the update of rx_packets stats at interface happens
+ * asynchronously to the bfd_rx_packets() function, the 'diff' value
+ * can be jittered. Thusly, we double the decay_rx_ctl to provide
+ * more wiggle room. */
+ diff = bfd_rx_packets(bfd) - bfd->decay_rx_packets;
+ expect = 2 * MAX(bfd->decay_rx_ctl, 1);
+ bfd->in_decay = diff <= expect ? true : false;
+ bfd_decay_update(bfd);
+}
+
+/* Updates the rx_packets, decay_rx_ctl and decay_detect_time. */
+static void
+bfd_decay_update(struct bfd * bfd) OVS_REQUIRES(mutex)
+{
+ bfd->decay_rx_packets = bfd_rx_packets(bfd);
+ bfd->decay_rx_ctl = 0;
+ bfd->decay_detect_time = MAX(bfd->decay_min_rx, 2000) + time_msec();
+}
+
+/* Checks if there are packets received during the time since last call.
+ * If forwarding_if_rx is enabled and packets are received, updates the
+ * forwarding_if_rx_detect_time. */
+static void
+bfd_check_rx(struct bfd *bfd) OVS_REQUIRES(mutex)
+{
+ uint64_t rx_packets = bfd_rx_packets(bfd);
+ int64_t diff;
+
+ diff = rx_packets - bfd->rx_packets;
+ bfd->rx_packets = rx_packets;
+ if (diff < 0) {
+ VLOG_INFO_RL(&rl, "rx_packets count is smaller than last time.");
+ }
+ if (bfd->forwarding_if_rx && diff > 0) {
+ bfd_forwarding_if_rx_update(bfd);
+ }
+}
+
+/* Updates the forwarding_if_rx_detect_time. */
+static void
+bfd_forwarding_if_rx_update(struct bfd *bfd) OVS_REQUIRES(mutex)
+{
+ int64_t incr = bfd_rx_interval(bfd) * bfd->mult;
+ bfd->forwarding_if_rx_detect_time = MAX(incr, 2000) + time_msec();
+}
+
static uint32_t
generate_discriminator(void)
{