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/* Copyright (c) 2013 Nicira, Inc.
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at:
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* http://www.apache.org/licenses/LICENSE-2.0
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License. */
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#include <arpa/inet.h>
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#include "byte-order.h"
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#include "dynamic-string.h"
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#include "ovs-thread.h"
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#include "openvswitch/types.h"
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#include "poll-loop.h"
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VLOG_DEFINE_THIS_MODULE(bfd);
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* The goal of this module is to replace CFM with something both more flexible
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* and standards compliant. In service of this goal, the following needs to be
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* * Implement Demand mode.
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* * Go through the RFC line by line and verify we comply.
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* * Test against a hardware implementation. Preferably a popular one.
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* * Delete BFD packets with nw_ttl != 255 in the datapath to prevent DOS
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* - BFD show into ovs-bugtool.
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* - Set TOS/PCP on inner BFD frame, and outer tunnel header when encapped.
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* - Sending BFD messages should be in its own thread/process.
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* - Scale testing. How does it operate when there are large number of bfd
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* sessions? Do we ever have random flaps? What's the CPU utilization?
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* - Rely on data traffic for liveness by using BFD demand mode.
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* If we're receiving traffic on a port, we can safely assume it's up (modulo
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* unidrectional failures). BFD has a demand mode in which it can stay quiet
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* unless it feels the need to check the status of the port. Using this, we
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* can implement a strategy in which BFD only sends control messages on dark
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* - Depending on how one interprets the spec, it appears that a BFD session
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* can never change bfd.LocalDiag to "No Diagnostic". We should verify that
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* this is what hardware implementations actually do. Seems like "No
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* Diagnostic" should be set once a BFD session state goes UP. */
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FLAG_MULTIPOINT = 1 << 0,
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STATE_ADMIN_DOWN = 0 << 6,
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DIAG_NONE = 0, /* No Diagnostic. */
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DIAG_EXPIRED = 1, /* Control Detection Time Expired. */
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DIAG_ECHO_FAILED = 2, /* Echo Function Failed. */
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DIAG_RMT_DOWN = 3, /* Neighbor Signaled Session Down. */
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DIAG_FWD_RESET = 4, /* Forwarding Plane Reset. */
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DIAG_PATH_DOWN = 5, /* Path Down. */
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DIAG_CPATH_DOWN = 6, /* Concatenated Path Down. */
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DIAG_ADMIN_DOWN = 7, /* Administratively Down. */
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DIAG_RCPATH_DOWN = 8 /* Reverse Concatenated Path Down. */
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/* RFC 5880 Section 4.1
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* 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
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* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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* |Vers | Diag |Sta|P|F|C|A|D|M| Detect Mult | Length |
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* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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* | My Discriminator |
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* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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* | Your Discriminator |
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* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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* | Desired Min TX Interval |
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* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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* | Required Min RX Interval |
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* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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* | Required Min Echo RX Interval |
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* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ */
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uint8_t vers_diag; /* Version and diagnostic. */
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uint8_t flags; /* 2bit State field followed by flags. */
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uint8_t mult; /* Fault detection multiplier. */
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uint8_t length; /* Length of this BFD message. */
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ovs_be32 my_disc; /* My discriminator. */
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ovs_be32 your_disc; /* Your discriminator. */
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ovs_be32 min_tx; /* Desired minimum tx interval. */
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ovs_be32 min_rx; /* Required minimum rx interval. */
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ovs_be32 min_rx_echo; /* Required minimum echo rx interval. */
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BUILD_ASSERT_DECL(BFD_PACKET_LEN == sizeof(struct msg));
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#define DIAG_MASK 0x1f
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#define STATE_MASK 0xC0
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#define FLAGS_MASK 0x3f
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struct hmap_node node; /* In 'all_bfds'. */
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uint32_t disc; /* bfd.LocalDiscr. Key in 'all_bfds' hmap. */
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char *name; /* Name used for logging. */
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bool cpath_down; /* Concatenated Path Down. */
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uint8_t mult; /* bfd.DetectMult. */
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enum state state; /* bfd.SessionState. */
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enum state rmt_state; /* bfd.RemoteSessionState. */
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enum diag diag; /* bfd.LocalDiag. */
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enum diag rmt_diag; /* Remote diagnostic. */
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enum flags flags; /* Flags sent on messages. */
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enum flags rmt_flags; /* Flags last received. */
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uint32_t rmt_disc; /* bfd.RemoteDiscr. */
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uint8_t eth_dst[ETH_ADDR_LEN];/* Ethernet destination address. */
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bool eth_dst_set; /* 'eth_dst' set through database. */
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uint16_t udp_src; /* UDP source port. */
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/* All timers in milliseconds. */
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long long int rmt_min_rx; /* bfd.RemoteMinRxInterval. */
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long long int rmt_min_tx; /* Remote minimum TX interval. */
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long long int cfg_min_tx; /* Configured minimum TX rate. */
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long long int cfg_min_rx; /* Configured required minimum RX rate. */
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long long int poll_min_tx; /* Min TX negotating in a poll sequence. */
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long long int poll_min_rx; /* Min RX negotating in a poll sequence. */
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long long int min_tx; /* bfd.DesiredMinTxInterval. */
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long long int min_rx; /* bfd.RequiredMinRxInterval. */
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long long int last_tx; /* Last TX time. */
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long long int next_tx; /* Next TX time. */
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long long int detect_time; /* RFC 5880 6.8.4 Detection time. */
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int forwarding_override; /* Manual override of 'forwarding' status. */
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atomic_bool check_tnl_key; /* Verify tunnel key of inbound packets? */
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static struct ovs_mutex mutex = OVS_MUTEX_INITIALIZER;
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static struct hmap all_bfds__ = HMAP_INITIALIZER(&all_bfds__);
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static struct hmap *const all_bfds OVS_GUARDED_BY(mutex) = &all_bfds__;
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static bool bfd_forwarding__(const struct bfd *) OVS_REQ_WRLOCK(mutex);
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static bool bfd_in_poll(const struct bfd *) OVS_REQ_WRLOCK(&mutex);
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static void bfd_poll(struct bfd *bfd) OVS_REQ_WRLOCK(&mutex);
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static const char *bfd_diag_str(enum diag) OVS_REQ_WRLOCK(&mutex);
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static const char *bfd_state_str(enum state) OVS_REQ_WRLOCK(&mutex);
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static long long int bfd_min_tx(const struct bfd *) OVS_REQ_WRLOCK(&mutex);
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static long long int bfd_tx_interval(const struct bfd *)
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OVS_REQ_WRLOCK(&mutex);
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static long long int bfd_rx_interval(const struct bfd *)
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OVS_REQ_WRLOCK(&mutex);
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static void bfd_set_next_tx(struct bfd *) OVS_REQ_WRLOCK(&mutex);
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static void bfd_set_state(struct bfd *, enum state, enum diag)
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OVS_REQ_WRLOCK(&mutex);
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static uint32_t generate_discriminator(void) OVS_REQ_WRLOCK(&mutex);
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static void bfd_put_details(struct ds *, const struct bfd *)
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OVS_REQ_WRLOCK(&mutex);
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static void bfd_unixctl_show(struct unixctl_conn *, int argc,
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const char *argv[], void *aux OVS_UNUSED);
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static void bfd_unixctl_set_forwarding_override(struct unixctl_conn *,
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int argc, const char *argv[],
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void *aux OVS_UNUSED);
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static void log_msg(enum vlog_level, const struct msg *, const char *message,
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const struct bfd *) OVS_REQ_WRLOCK(&mutex);
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static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(20, 20);
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/* Returns true if the interface on which 'bfd' is running may be used to
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* forward traffic according to the BFD session state. */
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bfd_forwarding(const struct bfd *bfd) OVS_EXCLUDED(mutex)
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ovs_mutex_lock(&mutex);
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ret = bfd_forwarding__(bfd);
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ovs_mutex_unlock(&mutex);
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/* Returns a 'smap' of key value pairs representing the status of 'bfd'
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* intended for the OVS database. */
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bfd_get_status(const struct bfd *bfd, struct smap *smap)
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ovs_mutex_lock(&mutex);
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smap_add(smap, "forwarding", bfd_forwarding__(bfd)? "true" : "false");
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smap_add(smap, "state", bfd_state_str(bfd->state));
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smap_add(smap, "diagnostic", bfd_diag_str(bfd->diag));
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if (bfd->state != STATE_DOWN) {
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smap_add(smap, "remote_state", bfd_state_str(bfd->rmt_state));
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smap_add(smap, "remote_diagnostic", bfd_diag_str(bfd->rmt_diag));
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ovs_mutex_unlock(&mutex);
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/* Initializes, destroys, or reconfigures the BFD session 'bfd' (named 'name'),
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* according to the database configuration contained in 'cfg'. Takes ownership
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* of 'bfd', which may be NULL. Returns a BFD object which may be used as a
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* handle for the session, or NULL if BFD is not enabled according to 'cfg'.
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* Also returns NULL if cfg is NULL. */
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bfd_configure(struct bfd *bfd, const char *name, const struct smap *cfg)
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static struct ovsthread_once once = OVSTHREAD_ONCE_INITIALIZER;
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static atomic_uint16_t udp_src = ATOMIC_VAR_INIT(0);
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long long int min_tx, min_rx;
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uint8_t ea[ETH_ADDR_LEN];
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if (ovsthread_once_start(&once)) {
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unixctl_command_register("bfd/show", "[interface]", 0, 1,
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bfd_unixctl_show, NULL);
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unixctl_command_register("bfd/set-forwarding",
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"[interface] normal|false|true", 1, 2,
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bfd_unixctl_set_forwarding_override, NULL);
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ovsthread_once_done(&once);
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if (!cfg || !smap_get_bool(cfg, "enable", false)) {
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ovs_mutex_lock(&mutex);
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bfd = xzalloc(sizeof *bfd);
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bfd->name = xstrdup(name);
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bfd->forwarding_override = -1;
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bfd->disc = generate_discriminator();
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hmap_insert(all_bfds, &bfd->node, bfd->disc);
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bfd->diag = DIAG_NONE;
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atomic_init(&bfd->ref_cnt, 1);
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/* RFC 5881 section 4
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* The source port MUST be in the range 49152 through 65535. The same
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* UDP source port number MUST be used for all BFD Control packets
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* associated with a particular session. The source port number SHOULD
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* be unique among all BFD sessions on the system. */
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atomic_add(&udp_src, 1, &bfd->udp_src);
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bfd->udp_src = (bfd->udp_src % 16384) + 49152;
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bfd_set_state(bfd, STATE_DOWN, DIAG_NONE);
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memcpy(bfd->eth_dst, eth_addr_bfd, ETH_ADDR_LEN);
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atomic_store(&bfd->check_tnl_key,
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smap_get_bool(cfg, "check_tnl_key", false));
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min_tx = smap_get_int(cfg, "min_tx", 100);
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min_tx = MAX(min_tx, 100);
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if (bfd->cfg_min_tx != min_tx) {
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bfd->cfg_min_tx = min_tx;
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if (bfd->state != STATE_UP
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|| (!bfd_in_poll(bfd) && bfd->cfg_min_tx < bfd->min_tx)) {
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bfd->min_tx = bfd->cfg_min_tx;
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min_rx = smap_get_int(cfg, "min_rx", 1000);
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min_rx = MAX(min_rx, 100);
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if (bfd->cfg_min_rx != min_rx) {
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bfd->cfg_min_rx = min_rx;
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if (bfd->state != STATE_UP
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|| (!bfd_in_poll(bfd) && bfd->cfg_min_rx > bfd->min_rx)) {
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bfd->min_rx = bfd->cfg_min_rx;
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cpath_down = smap_get_bool(cfg, "cpath_down", false);
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if (bfd->cpath_down != cpath_down) {
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bfd->cpath_down = cpath_down;
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if (bfd->diag == DIAG_NONE || bfd->diag == DIAG_CPATH_DOWN) {
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bfd_set_state(bfd, bfd->state, DIAG_NONE);
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hwaddr = smap_get(cfg, "bfd_dst_mac");
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if (hwaddr && eth_addr_from_string(hwaddr, ea) && !eth_addr_is_zero(ea)) {
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memcpy(bfd->eth_dst, ea, ETH_ADDR_LEN);
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bfd->eth_dst_set = true;
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} else if (bfd->eth_dst_set) {
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memcpy(bfd->eth_dst, eth_addr_bfd, ETH_ADDR_LEN);
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bfd->eth_dst_set = false;
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ovs_mutex_unlock(&mutex);
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bfd_ref(const struct bfd *bfd_)
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struct bfd *bfd = CONST_CAST(struct bfd *, bfd_);
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atomic_add(&bfd->ref_cnt, 1, &orig);
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ovs_assert(orig > 0);
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bfd_unref(struct bfd *bfd) OVS_EXCLUDED(mutex)
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atomic_sub(&bfd->ref_cnt, 1, &orig);
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ovs_assert(orig > 0);
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ovs_mutex_lock(&mutex);
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hmap_remove(all_bfds, &bfd->node);
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ovs_mutex_unlock(&mutex);
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bfd_wait(const struct bfd *bfd) OVS_EXCLUDED(mutex)
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ovs_mutex_lock(&mutex);
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if (bfd->flags & FLAG_FINAL) {
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poll_immediate_wake();
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poll_timer_wait_until(bfd->next_tx);
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if (bfd->state > STATE_DOWN) {
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poll_timer_wait_until(bfd->detect_time);
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ovs_mutex_unlock(&mutex);
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bfd_run(struct bfd *bfd) OVS_EXCLUDED(mutex)
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ovs_mutex_lock(&mutex);
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if (bfd->state > STATE_DOWN && time_msec() >= bfd->detect_time) {
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bfd_set_state(bfd, STATE_DOWN, DIAG_EXPIRED);
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if (bfd->min_tx != bfd->cfg_min_tx || bfd->min_rx != bfd->cfg_min_rx) {
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ovs_mutex_unlock(&mutex);
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bfd_should_send_packet(const struct bfd *bfd) OVS_EXCLUDED(mutex)
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ovs_mutex_lock(&mutex);
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ret = bfd->flags & FLAG_FINAL || time_msec() >= bfd->next_tx;
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ovs_mutex_unlock(&mutex);
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bfd_put_packet(struct bfd *bfd, struct ofpbuf *p,
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uint8_t eth_src[ETH_ADDR_LEN]) OVS_EXCLUDED(mutex)
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long long int min_tx, min_rx;
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struct udp_header *udp;
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struct eth_header *eth;
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struct ip_header *ip;
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ovs_mutex_lock(&mutex);
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long long int delay = time_msec() - bfd->next_tx;
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long long int interval = bfd_tx_interval(bfd);
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if (delay > interval * 3 / 2) {
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VLOG_INFO("%s: long delay of %lldms (expected %lldms) sending BFD"
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" control message", bfd->name, delay, interval);
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/* RFC 5880 Section 6.5
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* A BFD Control packet MUST NOT have both the Poll (P) and Final (F) bits
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ovs_assert(!(bfd->flags & FLAG_POLL) || !(bfd->flags & FLAG_FINAL));
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ofpbuf_reserve(p, 2); /* Properly align after the ethernet header. */
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eth = ofpbuf_put_uninit(p, sizeof *eth);
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memcpy(eth->eth_src, eth_src, ETH_ADDR_LEN);
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memcpy(eth->eth_dst, bfd->eth_dst, ETH_ADDR_LEN);
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eth->eth_type = htons(ETH_TYPE_IP);
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ip = ofpbuf_put_zeros(p, sizeof *ip);
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ip->ip_ihl_ver = IP_IHL_VER(5, 4);
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ip->ip_tot_len = htons(sizeof *ip + sizeof *udp + sizeof *msg);
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ip->ip_proto = IPPROTO_UDP;
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ip->ip_src = htonl(0xA9FE0100); /* 169.254.1.0 Link Local. */
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ip->ip_dst = htonl(0xA9FE0101); /* 169.254.1.1 Link Local. */
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ip->ip_csum = csum(ip, sizeof *ip);
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udp = ofpbuf_put_zeros(p, sizeof *udp);
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udp->udp_src = htons(bfd->udp_src);
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udp->udp_dst = htons(BFD_DEST_PORT);
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udp->udp_len = htons(sizeof *udp + sizeof *msg);
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msg = ofpbuf_put_uninit(p, sizeof *msg);
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msg->vers_diag = (BFD_VERSION << 5) | bfd->diag;
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msg->flags = (bfd->state & STATE_MASK) | bfd->flags;
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msg->mult = bfd->mult;
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msg->length = BFD_PACKET_LEN;
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msg->my_disc = htonl(bfd->disc);
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msg->your_disc = htonl(bfd->rmt_disc);
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msg->min_rx_echo = htonl(0);
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if (bfd_in_poll(bfd)) {
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min_tx = bfd->poll_min_tx;
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min_rx = bfd->poll_min_rx;
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min_tx = bfd_min_tx(bfd);
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min_rx = bfd->min_rx;
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msg->min_tx = htonl(min_tx * 1000);
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msg->min_rx = htonl(min_rx * 1000);
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bfd->flags &= ~FLAG_FINAL;
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log_msg(VLL_DBG, msg, "Sending BFD Message", bfd);
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bfd->last_tx = time_msec();
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bfd_set_next_tx(bfd);
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ovs_mutex_unlock(&mutex);
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bfd_should_process_flow(const struct bfd *bfd, const struct flow *flow,
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struct flow_wildcards *wc)
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memset(&wc->masks.dl_dst, 0xff, sizeof wc->masks.dl_dst);
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if (bfd->eth_dst_set && memcmp(bfd->eth_dst, flow->dl_dst, ETH_ADDR_LEN)) {
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memset(&wc->masks.nw_proto, 0xff, sizeof wc->masks.nw_proto);
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memset(&wc->masks.tp_dst, 0xff, sizeof wc->masks.tp_dst);
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atomic_read(&bfd->check_tnl_key, &check_tnl_key);
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memset(&wc->masks.tunnel.tun_id, 0xff, sizeof wc->masks.tunnel.tun_id);
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return (flow->dl_type == htons(ETH_TYPE_IP)
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&& flow->nw_proto == IPPROTO_UDP
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&& flow->tp_dst == htons(BFD_DEST_PORT)
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&& (check_tnl_key || flow->tunnel.tun_id == htonll(0)));
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bfd_process_packet(struct bfd *bfd, const struct flow *flow,
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const struct ofpbuf *p) OVS_EXCLUDED(mutex)
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uint32_t rmt_min_rx, pkt_your_disc;
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enum state rmt_state;
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/* This function is designed to follow section RFC 5880 6.8.6 closely. */
533
ovs_mutex_lock(&mutex);
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if (flow->nw_ttl != 255) {
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/* XXX Should drop in the kernel to prevent DOS. */
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msg = ofpbuf_at(p, (uint8_t *)p->l7 - (uint8_t *)p->data, BFD_PACKET_LEN);
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VLOG_INFO_RL(&rl, "%s: Received unparseable BFD control message.",
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/* RFC 5880 Section 6.8.6
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* If the Length field is greater than the payload of the encapsulating
548
* protocol, the packet MUST be discarded.
550
* Note that we make this check implicity. Above we use ofpbuf_at() to
551
* ensure that there are at least BFD_PACKET_LEN bytes in the payload of
552
* the encapsulating protocol. Below we require msg->length to be exactly
553
* BFD_PACKET_LEN bytes. */
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flags = msg->flags & FLAGS_MASK;
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rmt_state = msg->flags & STATE_MASK;
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version = msg->vers_diag >> VERS_SHIFT;
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log_msg(VLL_DBG, msg, "Received BFD control message", bfd);
561
if (version != BFD_VERSION) {
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log_msg(VLL_WARN, msg, "Incorrect version", bfd);
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/* Technically this should happen after the length check. We don't support
567
* authentication however, so it's simpler to do the check first. */
568
if (flags & FLAG_AUTH) {
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log_msg(VLL_WARN, msg, "Authenticated control message with"
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" authentication disabled", bfd);
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if (msg->length != BFD_PACKET_LEN) {
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log_msg(VLL_WARN, msg, "Unexpected length", bfd);
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if (msg->length < BFD_PACKET_LEN) {
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log_msg(VLL_WARN, msg, "Zero multiplier", bfd);
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if (flags & FLAG_MULTIPOINT) {
587
log_msg(VLL_WARN, msg, "Unsupported multipoint flag", bfd);
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log_msg(VLL_WARN, msg, "NULL my_disc", bfd);
596
pkt_your_disc = ntohl(msg->your_disc);
598
/* Technically, we should use the your discriminator field to figure
599
* out which 'struct bfd' this packet is destined towards. That way a
600
* bfd session could migrate from one interface to another
601
* transparently. This doesn't fit in with the OVS structure very
602
* well, so in this respect, we are not compliant. */
603
if (pkt_your_disc != bfd->disc) {
604
log_msg(VLL_WARN, msg, "Incorrect your_disc", bfd);
607
} else if (rmt_state > STATE_DOWN) {
608
log_msg(VLL_WARN, msg, "Null your_disc", bfd);
612
bfd->rmt_disc = ntohl(msg->my_disc);
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bfd->rmt_state = rmt_state;
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bfd->rmt_flags = flags;
615
bfd->rmt_diag = msg->vers_diag & DIAG_MASK;
617
if (flags & FLAG_FINAL && bfd_in_poll(bfd)) {
618
bfd->min_tx = bfd->poll_min_tx;
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bfd->min_rx = bfd->poll_min_rx;
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bfd->flags &= ~FLAG_POLL;
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log_msg(VLL_INFO, msg, "Poll sequence terminated", bfd);
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if (flags & FLAG_POLL) {
625
/* RFC 5880 Section 6.5
626
* When the other system receives a Poll, it immediately transmits a
627
* BFD Control packet with the Final (F) bit set, independent of any
628
* periodic BFD Control packets it may be sending
629
* (see section 6.8.7). */
630
bfd->flags &= ~FLAG_POLL;
631
bfd->flags |= FLAG_FINAL;
634
rmt_min_rx = MAX(ntohl(msg->min_rx) / 1000, 1);
635
if (bfd->rmt_min_rx != rmt_min_rx) {
636
bfd->rmt_min_rx = rmt_min_rx;
637
bfd_set_next_tx(bfd);
638
log_msg(VLL_INFO, msg, "New remote min_rx", bfd);
641
bfd->rmt_min_tx = MAX(ntohl(msg->min_tx) / 1000, 1);
642
bfd->detect_time = bfd_rx_interval(bfd) * bfd->mult + time_msec();
644
if (bfd->state == STATE_ADMIN_DOWN) {
645
VLOG_DBG_RL(&rl, "Administratively down, dropping control message.");
649
if (rmt_state == STATE_ADMIN_DOWN) {
650
if (bfd->state != STATE_DOWN) {
651
bfd_set_state(bfd, STATE_DOWN, DIAG_RMT_DOWN);
654
switch (bfd->state) {
656
if (rmt_state == STATE_DOWN) {
657
bfd_set_state(bfd, STATE_INIT, bfd->diag);
658
} else if (rmt_state == STATE_INIT) {
659
bfd_set_state(bfd, STATE_UP, bfd->diag);
663
if (rmt_state > STATE_DOWN) {
664
bfd_set_state(bfd, STATE_UP, bfd->diag);
668
if (rmt_state <= STATE_DOWN) {
669
bfd_set_state(bfd, STATE_DOWN, DIAG_RMT_DOWN);
670
log_msg(VLL_INFO, msg, "Remote signaled STATE_DOWN", bfd);
673
case STATE_ADMIN_DOWN:
678
/* XXX: RFC 5880 Section 6.8.6 Demand mode related calculations here. */
681
ovs_mutex_unlock(&mutex);
685
bfd_forwarding__(const struct bfd *bfd) OVS_REQ_WRLOCK(mutex)
687
if (bfd->forwarding_override != -1) {
688
return bfd->forwarding_override == 1;
691
return bfd->state == STATE_UP
692
&& bfd->rmt_diag != DIAG_PATH_DOWN
693
&& bfd->rmt_diag != DIAG_CPATH_DOWN
694
&& bfd->rmt_diag != DIAG_RCPATH_DOWN;
699
bfd_in_poll(const struct bfd *bfd) OVS_REQ_WRLOCK(mutex)
701
return (bfd->flags & FLAG_POLL) != 0;
705
bfd_poll(struct bfd *bfd) OVS_REQ_WRLOCK(mutex)
707
if (bfd->state > STATE_DOWN && !bfd_in_poll(bfd)
708
&& !(bfd->flags & FLAG_FINAL)) {
709
bfd->poll_min_tx = bfd->cfg_min_tx;
710
bfd->poll_min_rx = bfd->cfg_min_rx;
711
bfd->flags |= FLAG_POLL;
713
VLOG_INFO_RL(&rl, "%s: Initiating poll sequence", bfd->name);
718
bfd_min_tx(const struct bfd *bfd) OVS_REQ_WRLOCK(mutex)
720
/* RFC 5880 Section 6.8.3
721
* When bfd.SessionState is not Up, the system MUST set
722
* bfd.DesiredMinTxInterval to a value of not less than one second
723
* (1,000,000 microseconds). This is intended to ensure that the
724
* bandwidth consumed by BFD sessions that are not Up is negligible,
725
* particularly in the case where a neighbor may not be running BFD. */
726
return (bfd->state == STATE_UP ? bfd->min_tx : MAX(bfd->min_tx, 1000));
730
bfd_tx_interval(const struct bfd *bfd) OVS_REQ_WRLOCK(mutex)
732
long long int interval = bfd_min_tx(bfd);
733
return MAX(interval, bfd->rmt_min_rx);
737
bfd_rx_interval(const struct bfd *bfd) OVS_REQ_WRLOCK(mutex)
739
return MAX(bfd->min_rx, bfd->rmt_min_tx);
743
bfd_set_next_tx(struct bfd *bfd) OVS_REQ_WRLOCK(mutex)
745
long long int interval = bfd_tx_interval(bfd);
746
interval -= interval * random_range(26) / 100;
747
bfd->next_tx = bfd->last_tx + interval;
751
bfd_flag_str(enum flags flags)
753
struct ds ds = DS_EMPTY_INITIALIZER;
754
static char flag_str[128];
760
if (flags & FLAG_MULTIPOINT) {
761
ds_put_cstr(&ds, "multipoint ");
764
if (flags & FLAG_DEMAND) {
765
ds_put_cstr(&ds, "demand ");
768
if (flags & FLAG_AUTH) {
769
ds_put_cstr(&ds, "auth ");
772
if (flags & FLAG_CTL) {
773
ds_put_cstr(&ds, "ctl ");
776
if (flags & FLAG_FINAL) {
777
ds_put_cstr(&ds, "final ");
780
if (flags & FLAG_POLL) {
781
ds_put_cstr(&ds, "poll ");
784
ovs_strlcpy(flag_str, ds_cstr(&ds), sizeof flag_str);
790
bfd_state_str(enum state state)
793
case STATE_ADMIN_DOWN: return "admin_down";
794
case STATE_DOWN: return "down";
795
case STATE_INIT: return "init";
796
case STATE_UP: return "up";
797
default: return "invalid";
802
bfd_diag_str(enum diag diag) {
804
case DIAG_NONE: return "No Diagnostic";
805
case DIAG_EXPIRED: return "Control Detection Time Expired";
806
case DIAG_ECHO_FAILED: return "Echo Function Failed";
807
case DIAG_RMT_DOWN: return "Neighbor Signaled Session Down";
808
case DIAG_FWD_RESET: return "Forwarding Plane Reset";
809
case DIAG_PATH_DOWN: return "Path Down";
810
case DIAG_CPATH_DOWN: return "Concatenated Path Down";
811
case DIAG_ADMIN_DOWN: return "Administratively Down";
812
case DIAG_RCPATH_DOWN: return "Reverse Concatenated Path Down";
813
default: return "Invalid Diagnostic";
818
log_msg(enum vlog_level level, const struct msg *p, const char *message,
819
const struct bfd *bfd) OVS_REQ_WRLOCK(mutex)
821
struct ds ds = DS_EMPTY_INITIALIZER;
823
if (vlog_should_drop(THIS_MODULE, level, &rl)) {
829
"\n\tvers:%"PRIu8" diag:\"%s\" state:%s mult:%"PRIu8
832
"\n\tmy_disc:0x%"PRIx32" your_disc:0x%"PRIx32
833
"\n\tmin_tx:%"PRIu32"us (%"PRIu32"ms)"
834
"\n\tmin_rx:%"PRIu32"us (%"PRIu32"ms)"
835
"\n\tmin_rx_echo:%"PRIu32"us (%"PRIu32"ms)",
836
bfd->name, message, p->vers_diag >> VERS_SHIFT,
837
bfd_diag_str(p->vers_diag & DIAG_MASK),
838
bfd_state_str(p->flags & STATE_MASK),
839
p->mult, p->length, bfd_flag_str(p->flags & FLAGS_MASK),
840
ntohl(p->my_disc), ntohl(p->your_disc),
841
ntohl(p->min_tx), ntohl(p->min_tx) / 1000,
842
ntohl(p->min_rx), ntohl(p->min_rx) / 1000,
843
ntohl(p->min_rx_echo), ntohl(p->min_rx_echo) / 1000);
844
bfd_put_details(&ds, bfd);
845
VLOG(level, "%s", ds_cstr(&ds));
850
bfd_set_state(struct bfd *bfd, enum state state, enum diag diag)
851
OVS_REQ_WRLOCK(mutex)
853
if (diag == DIAG_NONE && bfd->cpath_down) {
854
diag = DIAG_CPATH_DOWN;
857
if (bfd->state != state || bfd->diag != diag) {
858
if (!VLOG_DROP_INFO(&rl)) {
859
struct ds ds = DS_EMPTY_INITIALIZER;
861
ds_put_format(&ds, "%s: BFD state change: %s->%s"
862
" \"%s\"->\"%s\".\n",
863
bfd->name, bfd_state_str(bfd->state),
864
bfd_state_str(state), bfd_diag_str(bfd->diag),
866
bfd_put_details(&ds, bfd);
867
VLOG_INFO("%s", ds_cstr(&ds));
874
if (bfd->state <= STATE_DOWN) {
875
bfd->rmt_state = STATE_DOWN;
876
bfd->rmt_diag = DIAG_NONE;
886
generate_discriminator(void)
890
/* RFC 5880 Section 6.8.1
891
* It SHOULD be set to a random (but still unique) value to improve
892
* security. The value is otherwise outside the scope of this
898
/* 'disc' is by definition random, so there's no reason to waste time
900
disc = random_uint32();
901
HMAP_FOR_EACH_IN_BUCKET (bfd, node, disc, all_bfds) {
902
if (bfd->disc == disc) {
913
bfd_find_by_name(const char *name) OVS_REQ_WRLOCK(mutex)
917
HMAP_FOR_EACH (bfd, node, all_bfds) {
918
if (!strcmp(bfd->name, name)) {
926
bfd_put_details(struct ds *ds, const struct bfd *bfd) OVS_REQ_WRLOCK(mutex)
928
ds_put_format(ds, "\tForwarding: %s\n",
929
bfd_forwarding__(bfd) ? "true" : "false");
930
ds_put_format(ds, "\tDetect Multiplier: %d\n", bfd->mult);
931
ds_put_format(ds, "\tConcatenated Path Down: %s\n",
932
bfd->cpath_down ? "true" : "false");
933
ds_put_format(ds, "\tTX Interval: Approx %lldms\n", bfd_tx_interval(bfd));
934
ds_put_format(ds, "\tRX Interval: Approx %lldms\n", bfd_rx_interval(bfd));
935
ds_put_format(ds, "\tDetect Time: now %+lldms\n",
936
time_msec() - bfd->detect_time);
937
ds_put_format(ds, "\tNext TX Time: now %+lldms\n",
938
time_msec() - bfd->next_tx);
939
ds_put_format(ds, "\tLast TX Time: now %+lldms\n",
940
time_msec() - bfd->last_tx);
942
ds_put_cstr(ds, "\n");
944
ds_put_format(ds, "\tLocal Flags: %s\n", bfd_flag_str(bfd->flags));
945
ds_put_format(ds, "\tLocal Session State: %s\n",
946
bfd_state_str(bfd->state));
947
ds_put_format(ds, "\tLocal Diagnostic: %s\n", bfd_diag_str(bfd->diag));
948
ds_put_format(ds, "\tLocal Discriminator: 0x%"PRIx32"\n", bfd->disc);
949
ds_put_format(ds, "\tLocal Minimum TX Interval: %lldms\n",
951
ds_put_format(ds, "\tLocal Minimum RX Interval: %lldms\n", bfd->min_rx);
953
ds_put_cstr(ds, "\n");
955
ds_put_format(ds, "\tRemote Flags: %s\n", bfd_flag_str(bfd->rmt_flags));
956
ds_put_format(ds, "\tRemote Session State: %s\n",
957
bfd_state_str(bfd->rmt_state));
958
ds_put_format(ds, "\tRemote Diagnostic: %s\n",
959
bfd_diag_str(bfd->rmt_diag));
960
ds_put_format(ds, "\tRemote Discriminator: 0x%"PRIx32"\n", bfd->rmt_disc);
961
ds_put_format(ds, "\tRemote Minimum TX Interval: %lldms\n",
963
ds_put_format(ds, "\tRemote Minimum RX Interval: %lldms\n",
968
bfd_unixctl_show(struct unixctl_conn *conn, int argc, const char *argv[],
969
void *aux OVS_UNUSED) OVS_EXCLUDED(mutex)
971
struct ds ds = DS_EMPTY_INITIALIZER;
974
ovs_mutex_lock(&mutex);
976
bfd = bfd_find_by_name(argv[1]);
978
unixctl_command_reply_error(conn, "no such bfd object");
981
bfd_put_details(&ds, bfd);
983
HMAP_FOR_EACH (bfd, node, all_bfds) {
984
ds_put_format(&ds, "---- %s ----\n", bfd->name);
985
bfd_put_details(&ds, bfd);
988
unixctl_command_reply(conn, ds_cstr(&ds));
992
ovs_mutex_unlock(&mutex);
997
bfd_unixctl_set_forwarding_override(struct unixctl_conn *conn, int argc,
998
const char *argv[], void *aux OVS_UNUSED)
1001
const char *forward_str = argv[argc - 1];
1002
int forwarding_override;
1005
ovs_mutex_lock(&mutex);
1006
if (!strcasecmp("true", forward_str)) {
1007
forwarding_override = 1;
1008
} else if (!strcasecmp("false", forward_str)) {
1009
forwarding_override = 0;
1010
} else if (!strcasecmp("normal", forward_str)) {
1011
forwarding_override = -1;
1013
unixctl_command_reply_error(conn, "unknown fault string");
1018
bfd = bfd_find_by_name(argv[1]);
1020
unixctl_command_reply_error(conn, "no such BFD object");
1023
bfd->forwarding_override = forwarding_override;
1025
HMAP_FOR_EACH (bfd, node, all_bfds) {
1026
bfd->forwarding_override = forwarding_override;
1030
unixctl_command_reply(conn, "OK");
1033
ovs_mutex_unlock(&mutex);
added
removed
lib/bfd.c
