diff options
Diffstat (limited to 'bfdd/bfd.c')
| -rw-r--r-- | bfdd/bfd.c | 2069 |
1 files changed, 2069 insertions, 0 deletions
diff --git a/bfdd/bfd.c b/bfdd/bfd.c new file mode 100644 index 0000000..3096f47 --- /dev/null +++ b/bfdd/bfd.c @@ -0,0 +1,2069 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/********************************************************************* + * Copyright 2013 Cumulus Networks, LLC. All rights reserved. + * Copyright 2014,2015,2016,2017 Cumulus Networks, Inc. All rights reserved. + * + * bfd.c: implements the BFD protocol. + * + * Authors + * ------- + * Shrijeet Mukherjee [shm@cumulusnetworks.com] + * Kanna Rajagopal [kanna@cumulusnetworks.com] + * Radhika Mahankali [Radhika@cumulusnetworks.com] + */ + +#include <zebra.h> + +#include "lib/jhash.h" +#include "lib/network.h" + +#include "bfd.h" + +DEFINE_MTYPE_STATIC(BFDD, BFDD_CONFIG, "long-lived configuration memory"); +DEFINE_MTYPE_STATIC(BFDD, BFDD_PROFILE, "long-lived profile memory"); +DEFINE_MTYPE_STATIC(BFDD, BFDD_SESSION_OBSERVER, "Session observer"); +DEFINE_MTYPE_STATIC(BFDD, BFDD_VRF, "BFD VRF"); + +/* + * Prototypes + */ +static uint32_t ptm_bfd_gen_ID(void); +static void ptm_bfd_echo_xmt_TO(struct bfd_session *bfd); +static struct bfd_session *bfd_find_disc(struct sockaddr_any *sa, + uint32_t ldisc); +static int bfd_session_update(struct bfd_session *bs, struct bfd_peer_cfg *bpc); +static const char *get_diag_str(int diag); + +static void bs_admin_down_handler(struct bfd_session *bs, int nstate); +static void bs_down_handler(struct bfd_session *bs, int nstate); +static void bs_init_handler(struct bfd_session *bs, int nstate); +static void bs_up_handler(struct bfd_session *bs, int nstate); + +/** + * Remove BFD profile from all BFD sessions so we don't leave dangling + * pointers. + */ +static void bfd_profile_detach(struct bfd_profile *bp); + +/* Zeroed array with the size of an IPv6 address. */ +struct in6_addr zero_addr; + +/** BFD profiles list. */ +struct bfdproflist bplist; + +/* + * Functions + */ +struct bfd_profile *bfd_profile_lookup(const char *name) +{ + struct bfd_profile *bp; + + TAILQ_FOREACH (bp, &bplist, entry) { + if (strcmp(name, bp->name)) + continue; + + return bp; + } + + return NULL; +} + +static void bfd_profile_set_default(struct bfd_profile *bp) +{ + bp->admin_shutdown = false; + bp->detection_multiplier = BFD_DEFDETECTMULT; + bp->echo_mode = false; + bp->passive = false; + bp->minimum_ttl = BFD_DEF_MHOP_TTL; + bp->min_echo_rx = BFD_DEF_REQ_MIN_ECHO_RX; + bp->min_echo_tx = BFD_DEF_DES_MIN_ECHO_TX; + bp->min_rx = BFD_DEFREQUIREDMINRX; + bp->min_tx = BFD_DEFDESIREDMINTX; +} + +struct bfd_profile *bfd_profile_new(const char *name) +{ + struct bfd_profile *bp; + + /* Search for duplicates. */ + if (bfd_profile_lookup(name) != NULL) + return NULL; + + /* Allocate, name it and put into list. */ + bp = XCALLOC(MTYPE_BFDD_PROFILE, sizeof(*bp)); + strlcpy(bp->name, name, sizeof(bp->name)); + TAILQ_INSERT_TAIL(&bplist, bp, entry); + + /* Set default values. */ + bfd_profile_set_default(bp); + + return bp; +} + +void bfd_profile_free(struct bfd_profile *bp) +{ + /* Detach from any session. */ + if (bglobal.bg_shutdown == false) + bfd_profile_detach(bp); + + /* Remove from global list. */ + TAILQ_REMOVE(&bplist, bp, entry); + + XFREE(MTYPE_BFDD_PROFILE, bp); +} + +void bfd_profile_apply(const char *profname, struct bfd_session *bs) +{ + struct bfd_profile *bp; + + /* Remove previous profile if any. */ + if (bs->profile_name) { + /* We are changing profiles. */ + if (strcmp(bs->profile_name, profname)) { + XFREE(MTYPE_BFDD_PROFILE, bs->profile_name); + bs->profile_name = + XSTRDUP(MTYPE_BFDD_PROFILE, profname); + } + } else /* Save the current profile name (in case it doesn't exist). */ + bs->profile_name = XSTRDUP(MTYPE_BFDD_PROFILE, profname); + + /* Look up new profile to apply. */ + bp = bfd_profile_lookup(profname); + + /* Point to profile if it exists. */ + bs->profile = bp; + + /* Apply configuration. */ + bfd_session_apply(bs); +} + +void bfd_session_apply(struct bfd_session *bs) +{ + struct bfd_profile *bp; + uint32_t min_tx = bs->timers.desired_min_tx; + uint32_t min_rx = bs->timers.required_min_rx; + + /* Pick the source of configuration. */ + bp = bs->profile ? bs->profile : &bs->peer_profile; + + /* Set multiplier if not the default. */ + if (bs->peer_profile.detection_multiplier == BFD_DEFDETECTMULT) + bs->detect_mult = bp->detection_multiplier; + else + bs->detect_mult = bs->peer_profile.detection_multiplier; + + /* Set timers if not the default. */ + if (bs->peer_profile.min_tx == BFD_DEFDESIREDMINTX) + bs->timers.desired_min_tx = bp->min_tx; + else + bs->timers.desired_min_tx = bs->peer_profile.min_tx; + + if (bs->peer_profile.min_rx == BFD_DEFREQUIREDMINRX) + bs->timers.required_min_rx = bp->min_rx; + else + bs->timers.required_min_rx = bs->peer_profile.min_rx; + + /* We can only apply echo options on single hop sessions. */ + if (!CHECK_FLAG(bs->flags, BFD_SESS_FLAG_MH)) { + /* Configure echo timers if they were default. */ + if (bs->peer_profile.min_echo_rx == BFD_DEF_REQ_MIN_ECHO_RX) + bs->timers.required_min_echo_rx = bp->min_echo_rx; + else + bs->timers.required_min_echo_rx = + bs->peer_profile.min_echo_rx; + + if (bs->peer_profile.min_echo_tx == BFD_DEF_DES_MIN_ECHO_TX) + bs->timers.desired_min_echo_tx = bp->min_echo_tx; + else + bs->timers.desired_min_echo_tx = + bs->peer_profile.min_echo_tx; + + /* Toggle echo if default value. */ + if (bs->peer_profile.echo_mode == false) + bfd_set_echo(bs, bp->echo_mode); + else + bfd_set_echo(bs, bs->peer_profile.echo_mode); + } else { + /* Configure the TTL packet filter. */ + if (bs->peer_profile.minimum_ttl == BFD_DEF_MHOP_TTL) + bs->mh_ttl = bp->minimum_ttl; + else + bs->mh_ttl = bs->peer_profile.minimum_ttl; + } + + /* Toggle 'passive-mode' if default value. */ + if (bs->peer_profile.passive == false) + bfd_set_passive_mode(bs, bp->passive); + else + bfd_set_passive_mode(bs, bs->peer_profile.passive); + + /* Toggle 'no shutdown' if default value. */ + if (bs->peer_profile.admin_shutdown == false) + bfd_set_shutdown(bs, bp->admin_shutdown); + else + bfd_set_shutdown(bs, bs->peer_profile.admin_shutdown); + + /* If session interval changed negotiate new timers. */ + if (bs->ses_state == PTM_BFD_UP + && (bs->timers.desired_min_tx != min_tx + || bs->timers.required_min_rx != min_rx)) + bfd_set_polling(bs); + + /* Send updated information to data plane. */ + bfd_dplane_update_session(bs); +} + +void bfd_profile_remove(struct bfd_session *bs) +{ + /* Remove any previous set profile name. */ + XFREE(MTYPE_BFDD_PROFILE, bs->profile_name); + bs->profile = NULL; + + bfd_session_apply(bs); +} + +void gen_bfd_key(struct bfd_key *key, struct sockaddr_any *peer, + struct sockaddr_any *local, bool mhop, const char *ifname, + const char *vrfname) +{ + memset(key, 0, sizeof(*key)); + + switch (peer->sa_sin.sin_family) { + case AF_INET: + key->family = AF_INET; + memcpy(&key->peer, &peer->sa_sin.sin_addr, + sizeof(peer->sa_sin.sin_addr)); + memcpy(&key->local, &local->sa_sin.sin_addr, + sizeof(local->sa_sin.sin_addr)); + break; + case AF_INET6: + key->family = AF_INET6; + memcpy(&key->peer, &peer->sa_sin6.sin6_addr, + sizeof(peer->sa_sin6.sin6_addr)); + memcpy(&key->local, &local->sa_sin6.sin6_addr, + sizeof(local->sa_sin6.sin6_addr)); + break; + } + + key->mhop = mhop; + if (ifname && ifname[0]) + strlcpy(key->ifname, ifname, sizeof(key->ifname)); + if (vrfname && vrfname[0]) + strlcpy(key->vrfname, vrfname, sizeof(key->vrfname)); + else + strlcpy(key->vrfname, VRF_DEFAULT_NAME, sizeof(key->vrfname)); +} + +struct bfd_session *bs_peer_find(struct bfd_peer_cfg *bpc) +{ + struct bfd_session *bs; + struct peer_label *pl; + struct bfd_key key; + + /* Try to find label first. */ + if (bpc->bpc_has_label) { + pl = pl_find(bpc->bpc_label); + if (pl != NULL) { + bs = pl->pl_bs; + return bs; + } + } + + /* Otherwise fallback to peer/local hash lookup. */ + gen_bfd_key(&key, &bpc->bpc_peer, &bpc->bpc_local, bpc->bpc_mhop, + bpc->bpc_localif, bpc->bpc_vrfname); + + return bfd_key_lookup(key); +} + +/* + * Starts a disabled BFD session. + * + * A session is disabled when the specified interface/VRF doesn't exist + * yet. It might happen on FRR boot or with virtual interfaces. + */ +int bfd_session_enable(struct bfd_session *bs) +{ + struct interface *ifp = NULL; + struct vrf *vrf = NULL; + int psock; + + /* We are using data plane, we don't need software. */ + if (bs->bdc) + return 0; + + /* + * If the interface or VRF doesn't exist, then we must register + * the session but delay its start. + */ + if (bs->key.vrfname[0]) { + vrf = vrf_lookup_by_name(bs->key.vrfname); + if (vrf == NULL) { + zlog_err( + "session-enable: specified VRF %s doesn't exists.", + bs->key.vrfname); + return 0; + } + } else { + vrf = vrf_lookup_by_id(VRF_DEFAULT); + } + + assert(vrf); + + if (bs->key.ifname[0]) { + ifp = if_lookup_by_name(bs->key.ifname, vrf->vrf_id); + if (ifp == NULL) { + zlog_err( + "session-enable: specified interface %s (VRF %s) doesn't exist.", + bs->key.ifname, vrf->name); + return 0; + } + } + + /* Assign interface/VRF pointers. */ + bs->vrf = vrf; + + /* Assign interface pointer (if any). */ + bs->ifp = ifp; + + /* Attempt to use data plane. */ + if (bglobal.bg_use_dplane && bfd_dplane_add_session(bs) == 0) { + control_notify_config(BCM_NOTIFY_CONFIG_ADD, bs); + return 0; + } + + /* Sanity check: don't leak open sockets. */ + if (bs->sock != -1) { + if (bglobal.debug_peer_event) + zlog_debug("%s: previous socket open", __func__); + + close(bs->sock); + bs->sock = -1; + } + + /* + * Get socket for transmitting control packets. Note that if we + * could use the destination port (3784) for the source + * port we wouldn't need a socket per session. + */ + if (CHECK_FLAG(bs->flags, BFD_SESS_FLAG_IPV6) == 0) { + psock = bp_peer_socket(bs); + if (psock == -1) + return 0; + } else { + psock = bp_peer_socketv6(bs); + if (psock == -1) + return 0; + } + + /* + * We've got a valid socket, lets start the timers and the + * protocol. + */ + bs->sock = psock; + + /* Only start timers if we are using active mode. */ + if (CHECK_FLAG(bs->flags, BFD_SESS_FLAG_PASSIVE) == 0) { + bfd_recvtimer_update(bs); + ptm_bfd_start_xmt_timer(bs, false); + } + + /* initialize RTT */ + bfd_rtt_init(bs); + + return 0; +} + +/* + * Disabled a running BFD session. + * + * A session is disabled when the specified interface/VRF gets removed + * (e.g. virtual interfaces). + */ +void bfd_session_disable(struct bfd_session *bs) +{ + /* We are using data plane, we don't need software. */ + if (bs->bdc) + return; + + /* Free up socket resources. */ + if (bs->sock != -1) { + close(bs->sock); + bs->sock = -1; + } + + /* Disable all timers. */ + bfd_recvtimer_delete(bs); + bfd_xmttimer_delete(bs); + ptm_bfd_echo_stop(bs); + + /* Set session down so it doesn't report UP and disabled. */ + ptm_bfd_sess_dn(bs, BD_PATH_DOWN); +} + +static uint32_t ptm_bfd_gen_ID(void) +{ + uint32_t session_id; + + /* + * RFC 5880, Section 6.8.1. recommends that we should generate + * random session identification numbers. + */ + do { + session_id = ((frr_weak_random() << 16) & 0xFFFF0000) + | (frr_weak_random() & 0x0000FFFF); + } while (session_id == 0 || bfd_id_lookup(session_id) != NULL); + + return session_id; +} + +void ptm_bfd_start_xmt_timer(struct bfd_session *bfd, bool is_echo) +{ + uint64_t jitter, xmt_TO; + int maxpercent; + + xmt_TO = is_echo ? bfd->echo_xmt_TO : bfd->xmt_TO; + + /* + * From section 6.5.2: trasmit interval should be randomly jittered + * between + * 75% and 100% of nominal value, unless detect_mult is 1, then should + * be + * between 75% and 90%. + */ + maxpercent = (bfd->detect_mult == 1) ? 16 : 26; + jitter = (xmt_TO * (75 + (frr_weak_random() % maxpercent))) / 100; + /* XXX remove that division above */ + + if (is_echo) + bfd_echo_xmttimer_update(bfd, jitter); + else + bfd_xmttimer_update(bfd, jitter); +} + +static void ptm_bfd_echo_xmt_TO(struct bfd_session *bfd) +{ + /* Send the scheduled echo packet */ + /* if ipv4 use the new echo implementation that causes + * the packet to be looped in forwarding plane of peer + */ + if (CHECK_FLAG(bfd->flags, BFD_SESS_FLAG_IPV6) == 0) +#ifdef BFD_LINUX + ptm_bfd_echo_fp_snd(bfd); +#else + ptm_bfd_echo_snd(bfd); +#endif + else + ptm_bfd_echo_snd(bfd); + + /* Restart the timer for next time */ + ptm_bfd_start_xmt_timer(bfd, true); +} + +void ptm_bfd_xmt_TO(struct bfd_session *bfd, int fbit) +{ + /* Send the scheduled control packet */ + ptm_bfd_snd(bfd, fbit); + + /* Restart the timer for next time */ + ptm_bfd_start_xmt_timer(bfd, false); +} + +void ptm_bfd_echo_stop(struct bfd_session *bfd) +{ + bfd->echo_xmt_TO = 0; + bfd->echo_detect_TO = 0; + UNSET_FLAG(bfd->flags, BFD_SESS_FLAG_ECHO_ACTIVE); + + bfd_echo_xmttimer_delete(bfd); + bfd_echo_recvtimer_delete(bfd); +} + +void ptm_bfd_echo_start(struct bfd_session *bfd) +{ + bfd->echo_detect_TO = (bfd->remote_detect_mult * bfd->echo_xmt_TO); + if (bfd->echo_detect_TO > 0) { + bfd_echo_recvtimer_update(bfd); + ptm_bfd_echo_xmt_TO(bfd); + } +} + +void ptm_bfd_sess_up(struct bfd_session *bfd) +{ + int old_state = bfd->ses_state; + + bfd->local_diag = 0; + bfd->ses_state = PTM_BFD_UP; + monotime(&bfd->uptime); + + /* Connection is up, lets negotiate timers. */ + bfd_set_polling(bfd); + + /* Start sending control packets with poll bit immediately. */ + ptm_bfd_snd(bfd, 0); + + control_notify(bfd, bfd->ses_state); + + if (old_state != bfd->ses_state) { + bfd->stats.session_up++; + if (bglobal.debug_peer_event) + zlog_debug("state-change: [%s] %s -> %s", + bs_to_string(bfd), state_list[old_state].str, + state_list[bfd->ses_state].str); + } +} + +void ptm_bfd_sess_dn(struct bfd_session *bfd, uint8_t diag) +{ + int old_state = bfd->ses_state; + + bfd->local_diag = diag; + bfd->discrs.remote_discr = 0; + bfd->ses_state = PTM_BFD_DOWN; + bfd->polling = 0; + bfd->demand_mode = 0; + monotime(&bfd->downtime); + + /* + * Only attempt to send if we have a valid socket: + * this function might be called by session disablers and in + * this case we won't have a valid socket (i.e. interface was + * removed or VRF doesn't exist anymore). + */ + if (bfd->sock != -1) + ptm_bfd_snd(bfd, 0); + + /* Slow down the control packets, the connection is down. */ + bs_set_slow_timers(bfd); + + /* only signal clients when going from up->down state */ + if (old_state == PTM_BFD_UP) + control_notify(bfd, PTM_BFD_DOWN); + + /* Stop echo packet transmission if they are active */ + if (CHECK_FLAG(bfd->flags, BFD_SESS_FLAG_ECHO_ACTIVE)) + ptm_bfd_echo_stop(bfd); + + /* Stop attempting to transmit or expect control packets if passive. */ + if (CHECK_FLAG(bfd->flags, BFD_SESS_FLAG_PASSIVE)) { + bfd_recvtimer_delete(bfd); + bfd_xmttimer_delete(bfd); + } + + if (old_state != bfd->ses_state) { + bfd->stats.session_down++; + if (bglobal.debug_peer_event) + zlog_debug("state-change: [%s] %s -> %s reason:%s", + bs_to_string(bfd), state_list[old_state].str, + state_list[bfd->ses_state].str, + get_diag_str(bfd->local_diag)); + } + + /* clear peer's mac address */ + UNSET_FLAG(bfd->flags, BFD_SESS_FLAG_MAC_SET); + memset(bfd->peer_hw_addr, 0, sizeof(bfd->peer_hw_addr)); + /* reset local address ,it might has been be changed after bfd is up*/ + memset(&bfd->local_address, 0, sizeof(bfd->local_address)); + + /* reset RTT */ + bfd_rtt_init(bfd); +} + +static struct bfd_session *bfd_find_disc(struct sockaddr_any *sa, + uint32_t ldisc) +{ + struct bfd_session *bs; + + bs = bfd_id_lookup(ldisc); + if (bs == NULL) + return NULL; + + switch (bs->key.family) { + case AF_INET: + if (memcmp(&sa->sa_sin.sin_addr, &bs->key.peer, + sizeof(sa->sa_sin.sin_addr))) + return NULL; + break; + case AF_INET6: + if (memcmp(&sa->sa_sin6.sin6_addr, &bs->key.peer, + sizeof(sa->sa_sin6.sin6_addr))) + return NULL; + break; + } + + return bs; +} + +struct bfd_session *ptm_bfd_sess_find(struct bfd_pkt *cp, + struct sockaddr_any *peer, + struct sockaddr_any *local, + struct interface *ifp, + vrf_id_t vrfid, + bool is_mhop) +{ + struct vrf *vrf; + struct bfd_key key; + + /* Find our session using the ID signaled by the remote end. */ + if (cp->discrs.remote_discr) + return bfd_find_disc(peer, ntohl(cp->discrs.remote_discr)); + + /* Search for session without using discriminator. */ + vrf = vrf_lookup_by_id(vrfid); + + gen_bfd_key(&key, peer, local, is_mhop, ifp ? ifp->name : NULL, + vrf ? vrf->name : VRF_DEFAULT_NAME); + + /* XXX maybe remoteDiscr should be checked for remoteHeard cases. */ + return bfd_key_lookup(key); +} + +void bfd_xmt_cb(struct event *t) +{ + struct bfd_session *bs = EVENT_ARG(t); + + ptm_bfd_xmt_TO(bs, 0); +} + +void bfd_echo_xmt_cb(struct event *t) +{ + struct bfd_session *bs = EVENT_ARG(t); + + if (bs->echo_xmt_TO > 0) + ptm_bfd_echo_xmt_TO(bs); +} + +/* Was ptm_bfd_detect_TO() */ +void bfd_recvtimer_cb(struct event *t) +{ + struct bfd_session *bs = EVENT_ARG(t); + + switch (bs->ses_state) { + case PTM_BFD_INIT: + case PTM_BFD_UP: + ptm_bfd_sess_dn(bs, BD_CONTROL_EXPIRED); + break; + } +} + +/* Was ptm_bfd_echo_detect_TO() */ +void bfd_echo_recvtimer_cb(struct event *t) +{ + struct bfd_session *bs = EVENT_ARG(t); + + switch (bs->ses_state) { + case PTM_BFD_INIT: + case PTM_BFD_UP: + ptm_bfd_sess_dn(bs, BD_ECHO_FAILED); + break; + } +} + +struct bfd_session *bfd_session_new(void) +{ + struct bfd_session *bs; + + bs = XCALLOC(MTYPE_BFDD_CONFIG, sizeof(*bs)); + + /* Set peer session defaults. */ + bfd_profile_set_default(&bs->peer_profile); + + bs->timers.desired_min_tx = BFD_DEFDESIREDMINTX; + bs->timers.required_min_rx = BFD_DEFREQUIREDMINRX; + bs->timers.required_min_echo_rx = BFD_DEF_REQ_MIN_ECHO_RX; + bs->timers.desired_min_echo_tx = BFD_DEF_DES_MIN_ECHO_TX; + bs->detect_mult = BFD_DEFDETECTMULT; + bs->mh_ttl = BFD_DEF_MHOP_TTL; + bs->ses_state = PTM_BFD_DOWN; + + /* Initiate connection with slow timers. */ + bs_set_slow_timers(bs); + + /* Initiate remote settings as well. */ + bs->remote_timers = bs->cur_timers; + bs->remote_detect_mult = BFD_DEFDETECTMULT; + + bs->sock = -1; + monotime(&bs->uptime); + bs->downtime = bs->uptime; + + return bs; +} + +int bfd_session_update_label(struct bfd_session *bs, const char *nlabel) +{ + /* New label treatment: + * - Check if the label is taken; + * - Try to allocate the memory for it and register; + */ + if (bs->pl == NULL) { + if (pl_find(nlabel) != NULL) { + /* Someone is already using it. */ + return -1; + } + + pl_new(nlabel, bs); + + return 0; + } + + /* + * Test label change consistency: + * - Do nothing if it's the same label; + * - Check if the future label is already taken; + * - Change label; + */ + if (strcmp(nlabel, bs->pl->pl_label) == 0) + return -1; + if (pl_find(nlabel) != NULL) + return -1; + + strlcpy(bs->pl->pl_label, nlabel, sizeof(bs->pl->pl_label)); + return 0; +} + +static void _bfd_session_update(struct bfd_session *bs, + struct bfd_peer_cfg *bpc) +{ + if (bpc->bpc_has_txinterval) { + bs->timers.desired_min_tx = bpc->bpc_txinterval * 1000; + bs->peer_profile.min_tx = bs->timers.desired_min_tx; + } + + if (bpc->bpc_has_recvinterval) { + bs->timers.required_min_rx = bpc->bpc_recvinterval * 1000; + bs->peer_profile.min_rx = bs->timers.required_min_rx; + } + + if (bpc->bpc_has_detectmultiplier) { + bs->detect_mult = bpc->bpc_detectmultiplier; + bs->peer_profile.detection_multiplier = bs->detect_mult; + } + + if (bpc->bpc_has_echorecvinterval) { + bs->timers.required_min_echo_rx = bpc->bpc_echorecvinterval * 1000; + bs->peer_profile.min_echo_rx = bs->timers.required_min_echo_rx; + } + + if (bpc->bpc_has_echotxinterval) { + bs->timers.desired_min_echo_tx = bpc->bpc_echotxinterval * 1000; + bs->peer_profile.min_echo_tx = bs->timers.desired_min_echo_tx; + } + + if (bpc->bpc_has_label) + bfd_session_update_label(bs, bpc->bpc_label); + + if (bpc->bpc_cbit) + SET_FLAG(bs->flags, BFD_SESS_FLAG_CBIT); + else + UNSET_FLAG(bs->flags, BFD_SESS_FLAG_CBIT); + + if (bpc->bpc_has_minimum_ttl) { + bs->mh_ttl = bpc->bpc_minimum_ttl; + bs->peer_profile.minimum_ttl = bpc->bpc_minimum_ttl; + } + + bs->peer_profile.echo_mode = bpc->bpc_echo; + bfd_set_echo(bs, bpc->bpc_echo); + + /* + * Shutdown needs to be the last in order to avoid timers enable when + * the session is disabled. + */ + bs->peer_profile.admin_shutdown = bpc->bpc_shutdown; + bfd_set_passive_mode(bs, bpc->bpc_passive); + bfd_set_shutdown(bs, bpc->bpc_shutdown); + + /* + * Apply profile last: it also calls `bfd_set_shutdown`. + * + * There is no problem calling `shutdown` twice if the value doesn't + * change or if it is overridden by peer specific configuration. + */ + if (bpc->bpc_has_profile) + bfd_profile_apply(bpc->bpc_profile, bs); +} + +static int bfd_session_update(struct bfd_session *bs, struct bfd_peer_cfg *bpc) +{ + /* User didn't want to update, return failure. */ + if (bpc->bpc_createonly) + return -1; + + _bfd_session_update(bs, bpc); + + control_notify_config(BCM_NOTIFY_CONFIG_UPDATE, bs); + + return 0; +} + +void bfd_session_free(struct bfd_session *bs) +{ + struct bfd_session_observer *bso; + + bfd_session_disable(bs); + + /* Remove session from data plane if any. */ + bfd_dplane_delete_session(bs); + + bfd_key_delete(bs->key); + bfd_id_delete(bs->discrs.my_discr); + + /* Remove observer if any. */ + TAILQ_FOREACH(bso, &bglobal.bg_obslist, bso_entry) { + if (bso->bso_bs != bs) + continue; + + break; + } + if (bso != NULL) + bs_observer_del(bso); + + pl_free(bs->pl); + + XFREE(MTYPE_BFDD_PROFILE, bs->profile_name); + XFREE(MTYPE_BFDD_CONFIG, bs); +} + +struct bfd_session *ptm_bfd_sess_new(struct bfd_peer_cfg *bpc) +{ + struct bfd_session *bfd, *l_bfd; + + /* check to see if this needs a new session */ + l_bfd = bs_peer_find(bpc); + if (l_bfd) { + /* Requesting a duplicated peer means update configuration. */ + if (bfd_session_update(l_bfd, bpc) == 0) + return l_bfd; + else + return NULL; + } + + /* Get BFD session storage with its defaults. */ + bfd = bfd_session_new(); + + /* + * Store interface/VRF name in case we need to delay session + * start. See `bfd_session_enable` for more information. + */ + if (bpc->bpc_has_localif) + strlcpy(bfd->key.ifname, bpc->bpc_localif, + sizeof(bfd->key.ifname)); + + if (bpc->bpc_has_vrfname) + strlcpy(bfd->key.vrfname, bpc->bpc_vrfname, + sizeof(bfd->key.vrfname)); + else + strlcpy(bfd->key.vrfname, VRF_DEFAULT_NAME, + sizeof(bfd->key.vrfname)); + + /* Copy remaining data. */ + if (bpc->bpc_ipv4 == false) + SET_FLAG(bfd->flags, BFD_SESS_FLAG_IPV6); + + bfd->key.family = (bpc->bpc_ipv4) ? AF_INET : AF_INET6; + switch (bfd->key.family) { + case AF_INET: + memcpy(&bfd->key.peer, &bpc->bpc_peer.sa_sin.sin_addr, + sizeof(bpc->bpc_peer.sa_sin.sin_addr)); + memcpy(&bfd->key.local, &bpc->bpc_local.sa_sin.sin_addr, + sizeof(bpc->bpc_local.sa_sin.sin_addr)); + break; + + case AF_INET6: + memcpy(&bfd->key.peer, &bpc->bpc_peer.sa_sin6.sin6_addr, + sizeof(bpc->bpc_peer.sa_sin6.sin6_addr)); + memcpy(&bfd->key.local, &bpc->bpc_local.sa_sin6.sin6_addr, + sizeof(bpc->bpc_local.sa_sin6.sin6_addr)); + break; + + default: + assert(1); + break; + } + + if (bpc->bpc_mhop) + SET_FLAG(bfd->flags, BFD_SESS_FLAG_MH); + + bfd->key.mhop = bpc->bpc_mhop; + + if (bs_registrate(bfd) == NULL) + return NULL; + + /* Apply other configurations. */ + _bfd_session_update(bfd, bpc); + + return bfd; +} + +struct bfd_session *bs_registrate(struct bfd_session *bfd) +{ + /* Registrate session into data structures. */ + bfd_key_insert(bfd); + bfd->discrs.my_discr = ptm_bfd_gen_ID(); + bfd_id_insert(bfd); + + /* Try to enable session and schedule for packet receive/send. */ + if (bfd_session_enable(bfd) == -1) { + /* Unrecoverable failure, remove the session/peer. */ + bfd_session_free(bfd); + return NULL; + } + + /* Add observer if we have moving parts. */ + if (bfd->key.ifname[0] || bfd->key.vrfname[0] || bfd->sock == -1) + bs_observer_add(bfd); + + if (bglobal.debug_peer_event) + zlog_debug("session-new: %s", bs_to_string(bfd)); + + control_notify_config(BCM_NOTIFY_CONFIG_ADD, bfd); + + return bfd; +} + +int ptm_bfd_sess_del(struct bfd_peer_cfg *bpc) +{ + struct bfd_session *bs; + + /* Find session and call free(). */ + bs = bs_peer_find(bpc); + if (bs == NULL) + return -1; + + /* This pointer is being referenced, don't let it be deleted. */ + if (bs->refcount > 0) { + zlog_err("session-delete: refcount failure: %" PRIu64" references", + bs->refcount); + return -1; + } + + if (bglobal.debug_peer_event) + zlog_debug("%s: %s", __func__, bs_to_string(bs)); + + control_notify_config(BCM_NOTIFY_CONFIG_DELETE, bs); + + bfd_session_free(bs); + + return 0; +} + +void bfd_set_polling(struct bfd_session *bs) +{ + /* + * Start polling procedure: the only timers that require polling + * to change value without losing connection are: + * + * - Desired minimum transmission interval; + * - Required minimum receive interval; + * + * RFC 5880, Section 6.8.3. + */ + bs->polling = 1; +} + +/* + * bs_<state>_handler() functions implement the BFD state machine + * transition mechanism. `<state>` is the current session state and + * the parameter `nstate` is the peer new state. + */ +static void bs_admin_down_handler(struct bfd_session *bs + __attribute__((__unused__)), + int nstate __attribute__((__unused__))) +{ + /* + * We are administratively down, there is no state machine + * handling. + */ +} + +static void bs_down_handler(struct bfd_session *bs, int nstate) +{ + switch (nstate) { + case PTM_BFD_ADM_DOWN: + /* + * Remote peer doesn't want to talk, so lets keep the + * connection down. + */ + case PTM_BFD_UP: + /* Peer can't be up yet, wait it go to 'init' or 'down'. */ + break; + + case PTM_BFD_DOWN: + /* + * Remote peer agreed that the path is down, lets try to + * bring it up. + */ + bs->ses_state = PTM_BFD_INIT; + + /* + * RFC 5880, Section 6.1. + * A system taking the Passive role MUST NOT begin + * sending BFD packets for a particular session until + * it has received a BFD packet for that session, and thus + * has learned the remote system's discriminator value. + * + * Now we can start transmission timer in passive mode. + */ + if (CHECK_FLAG(bs->flags, BFD_SESS_FLAG_PASSIVE)) + ptm_bfd_xmt_TO(bs, 0); + + break; + + case PTM_BFD_INIT: + /* + * Remote peer told us his path is up, lets turn + * activate the session. + */ + ptm_bfd_sess_up(bs); + break; + + default: + if (bglobal.debug_peer_event) + zlog_debug("state-change: unhandled neighbor state: %d", + nstate); + break; + } +} + +static void bs_init_handler(struct bfd_session *bs, int nstate) +{ + switch (nstate) { + case PTM_BFD_ADM_DOWN: + /* + * Remote peer doesn't want to talk, so lets make the + * connection down. + */ + ptm_bfd_sess_dn(bs, BD_NEIGHBOR_DOWN); + break; + + case PTM_BFD_DOWN: + /* Remote peer hasn't moved to first stage yet. */ + break; + + case PTM_BFD_INIT: + case PTM_BFD_UP: + /* We agreed on the settings and the path is up. */ + ptm_bfd_sess_up(bs); + break; + + default: + if (bglobal.debug_peer_event) + zlog_debug("state-change: unhandled neighbor state: %d", + nstate); + break; + } +} + +static void bs_up_handler(struct bfd_session *bs, int nstate) +{ + switch (nstate) { + case PTM_BFD_ADM_DOWN: + case PTM_BFD_DOWN: + /* Peer lost or asked to shutdown connection. */ + ptm_bfd_sess_dn(bs, BD_NEIGHBOR_DOWN); + break; + + case PTM_BFD_INIT: + case PTM_BFD_UP: + /* Path is up and working. */ + break; + + default: + if (bglobal.debug_peer_event) + zlog_debug("state-change: unhandled neighbor state: %d", + nstate); + break; + } +} + +void bs_state_handler(struct bfd_session *bs, int nstate) +{ + switch (bs->ses_state) { + case PTM_BFD_ADM_DOWN: + bs_admin_down_handler(bs, nstate); + break; + case PTM_BFD_DOWN: + bs_down_handler(bs, nstate); + break; + case PTM_BFD_INIT: + bs_init_handler(bs, nstate); + break; + case PTM_BFD_UP: + bs_up_handler(bs, nstate); + break; + + default: + if (bglobal.debug_peer_event) + zlog_debug("state-change: [%s] is in invalid state: %d", + bs_to_string(bs), nstate); + break; + } +} + +/* + * Handles echo timer manipulation after updating timer. + */ +void bs_echo_timer_handler(struct bfd_session *bs) +{ + uint32_t old_timer; + + /* + * Before doing any echo handling, check if it is possible to + * use it. + * + * - Check for `echo-mode` configuration. + * - Check that we are not using multi hop (RFC 5883, + * Section 3). + * - Check that we are already at the up state. + */ + if (CHECK_FLAG(bs->flags, BFD_SESS_FLAG_ECHO) == 0 + || CHECK_FLAG(bs->flags, BFD_SESS_FLAG_MH) + || bs->ses_state != PTM_BFD_UP) + return; + + /* Remote peer asked to stop echo. */ + if (bs->remote_timers.required_min_echo == 0) { + if (CHECK_FLAG(bs->flags, BFD_SESS_FLAG_ECHO_ACTIVE)) + ptm_bfd_echo_stop(bs); + + return; + } + + /* + * Calculate the echo transmission timer: we must not send + * echo packets faster than the minimum required time + * announced by the remote system. + * + * RFC 5880, Section 6.8.9. + */ + old_timer = bs->echo_xmt_TO; + if (bs->remote_timers.required_min_echo > bs->timers.desired_min_echo_tx) + bs->echo_xmt_TO = bs->remote_timers.required_min_echo; + else + bs->echo_xmt_TO = bs->timers.desired_min_echo_tx; + + if (CHECK_FLAG(bs->flags, BFD_SESS_FLAG_ECHO_ACTIVE) == 0 + || old_timer != bs->echo_xmt_TO) + ptm_bfd_echo_start(bs); +} + +/* + * RFC 5880 Section 6.5. + * + * When a BFD control packet with the final bit is received, we must + * update the session parameters. + */ +void bs_final_handler(struct bfd_session *bs) +{ + /* Start using our new timers. */ + bs->cur_timers.desired_min_tx = bs->timers.desired_min_tx; + bs->cur_timers.required_min_rx = bs->timers.required_min_rx; + + /* + * TODO: demand mode. See RFC 5880 Section 6.1. + * + * When using demand mode we must disable the detection timer + * for lost control packets. + */ + if (bs->demand_mode) { + /* Notify watchers about changed timers. */ + control_notify_config(BCM_NOTIFY_CONFIG_UPDATE, bs); + return; + } + + /* + * Calculate transmission time based on new timers. + * + * Transmission calculation: + * Unless specified by exceptions at the end of Section 6.8.7, the + * transmission time will be determined by the system with the + * slowest rate. + * + * RFC 5880, Section 6.8.7. + */ + if (bs->timers.desired_min_tx > bs->remote_timers.required_min_rx) + bs->xmt_TO = bs->timers.desired_min_tx; + else + bs->xmt_TO = bs->remote_timers.required_min_rx; + + /* Apply new transmission timer immediately. */ + ptm_bfd_start_xmt_timer(bs, false); + + /* Notify watchers about changed timers. */ + control_notify_config(BCM_NOTIFY_CONFIG_UPDATE, bs); +} + +void bs_set_slow_timers(struct bfd_session *bs) +{ + /* + * BFD connection must use slow timers before going up or after + * losing connectivity to avoid wasting bandwidth. + * + * RFC 5880, Section 6.8.3. + */ + bs->cur_timers.desired_min_tx = BFD_DEF_SLOWTX; + bs->cur_timers.required_min_rx = BFD_DEF_SLOWTX; + bs->cur_timers.required_min_echo = 0; + + /* Set the appropriated timeouts for slow connection. */ + bs->detect_TO = (BFD_DEFDETECTMULT * BFD_DEF_SLOWTX); + bs->xmt_TO = BFD_DEF_SLOWTX; +} + +void bfd_set_echo(struct bfd_session *bs, bool echo) +{ + if (echo) { + /* Check if echo mode is already active. */ + if (CHECK_FLAG(bs->flags, BFD_SESS_FLAG_ECHO)) + return; + + SET_FLAG(bs->flags, BFD_SESS_FLAG_ECHO); + + /* Activate/update echo receive timeout timer. */ + if (bs->bdc == NULL) + bs_echo_timer_handler(bs); + } else { + /* Check if echo mode is already disabled. */ + if (!CHECK_FLAG(bs->flags, BFD_SESS_FLAG_ECHO)) + return; + + UNSET_FLAG(bs->flags, BFD_SESS_FLAG_ECHO); + + /* Deactivate timeout timer. */ + if (bs->bdc == NULL) + ptm_bfd_echo_stop(bs); + } +} + +void bfd_set_shutdown(struct bfd_session *bs, bool shutdown) +{ + bool is_shutdown; + + /* + * Special case: we are batching changes and the previous state was + * not shutdown. Instead of potentially disconnect a running peer, + * we'll get the current status to validate we were really down. + */ + if (bs->ses_state == PTM_BFD_UP) + is_shutdown = false; + else + is_shutdown = CHECK_FLAG(bs->flags, BFD_SESS_FLAG_SHUTDOWN); + + if (shutdown) { + /* Already shutdown. */ + if (is_shutdown) + return; + + SET_FLAG(bs->flags, BFD_SESS_FLAG_SHUTDOWN); + + /* Handle data plane shutdown case. */ + if (bs->bdc) { + bs->ses_state = PTM_BFD_ADM_DOWN; + bfd_dplane_update_session(bs); + control_notify(bs, bs->ses_state); + return; + } + + /* Disable all events. */ + bfd_recvtimer_delete(bs); + bfd_echo_recvtimer_delete(bs); + bfd_xmttimer_delete(bs); + bfd_echo_xmttimer_delete(bs); + + /* Change and notify state change. */ + bs->ses_state = PTM_BFD_ADM_DOWN; + control_notify(bs, bs->ses_state); + + /* Don't try to send packets with a disabled session. */ + if (bs->sock != -1) + ptm_bfd_snd(bs, 0); + } else { + /* Already working. */ + if (!is_shutdown) + return; + + UNSET_FLAG(bs->flags, BFD_SESS_FLAG_SHUTDOWN); + + /* Handle data plane shutdown case. */ + if (bs->bdc) { + bs->ses_state = PTM_BFD_DOWN; + bfd_dplane_update_session(bs); + control_notify(bs, bs->ses_state); + return; + } + + /* Change and notify state change. */ + bs->ses_state = PTM_BFD_DOWN; + control_notify(bs, bs->ses_state); + + /* Enable timers if non passive, otherwise stop them. */ + if (CHECK_FLAG(bs->flags, BFD_SESS_FLAG_PASSIVE)) { + bfd_recvtimer_delete(bs); + bfd_xmttimer_delete(bs); + } else { + bfd_recvtimer_update(bs); + bfd_xmttimer_update(bs, bs->xmt_TO); + } + } +} + +void bfd_set_passive_mode(struct bfd_session *bs, bool passive) +{ + if (passive) { + SET_FLAG(bs->flags, BFD_SESS_FLAG_PASSIVE); + + /* Session is already up and running, nothing to do now. */ + if (bs->ses_state != PTM_BFD_DOWN) + return; + + /* Lets disable the timers since we are now passive. */ + bfd_recvtimer_delete(bs); + bfd_xmttimer_delete(bs); + } else { + UNSET_FLAG(bs->flags, BFD_SESS_FLAG_PASSIVE); + + /* Session is already up and running, nothing to do now. */ + if (bs->ses_state != PTM_BFD_DOWN) + return; + + /* Session is down, let it attempt to start the connection. */ + bfd_xmttimer_update(bs, bs->xmt_TO); + bfd_recvtimer_update(bs); + } +} + +/* + * Helper functions. + */ +static const char *get_diag_str(int diag) +{ + for (int i = 0; diag_list[i].str; i++) { + if (diag_list[i].type == diag) + return diag_list[i].str; + } + return "N/A"; +} + +const char *satostr(const struct sockaddr_any *sa) +{ +#define INETSTR_BUFCOUNT 8 + static char buf[INETSTR_BUFCOUNT][INET6_ADDRSTRLEN]; + static int bufidx; + const struct sockaddr_in *sin = &sa->sa_sin; + const struct sockaddr_in6 *sin6 = &sa->sa_sin6; + + bufidx += (bufidx + 1) % INETSTR_BUFCOUNT; + buf[bufidx][0] = 0; + + switch (sin->sin_family) { + case AF_INET: + inet_ntop(AF_INET, &sin->sin_addr, buf[bufidx], + sizeof(buf[bufidx])); + break; + case AF_INET6: + inet_ntop(AF_INET6, &sin6->sin6_addr, buf[bufidx], + sizeof(buf[bufidx])); + break; + + default: + strlcpy(buf[bufidx], "unknown", sizeof(buf[bufidx])); + break; + } + + return buf[bufidx]; +} + +const char *diag2str(uint8_t diag) +{ + switch (diag) { + case 0: + return "ok"; + case 1: + return "control detection time expired"; + case 2: + return "echo function failed"; + case 3: + return "neighbor signaled session down"; + case 4: + return "forwarding plane reset"; + case 5: + return "path down"; + case 6: + return "concatenated path down"; + case 7: + return "administratively down"; + case 8: + return "reverse concatenated path down"; + default: + return "unknown"; + } +} + +int strtosa(const char *addr, struct sockaddr_any *sa) +{ + memset(sa, 0, sizeof(*sa)); + + if (inet_pton(AF_INET, addr, &sa->sa_sin.sin_addr) == 1) { + sa->sa_sin.sin_family = AF_INET; +#ifdef HAVE_STRUCT_SOCKADDR_SA_LEN + sa->sa_sin.sin_len = sizeof(sa->sa_sin); +#endif /* HAVE_STRUCT_SOCKADDR_SA_LEN */ + return 0; + } + + if (inet_pton(AF_INET6, addr, &sa->sa_sin6.sin6_addr) == 1) { + sa->sa_sin6.sin6_family = AF_INET6; +#ifdef HAVE_STRUCT_SOCKADDR_SA_LEN + sa->sa_sin6.sin6_len = sizeof(sa->sa_sin6); +#endif /* HAVE_STRUCT_SOCKADDR_SA_LEN */ + return 0; + } + + return -1; +} + +void integer2timestr(uint64_t time, char *buf, size_t buflen) +{ + uint64_t year, month, day, hour, minute, second; + int rv; + +#define MINUTES (60) +#define HOURS (60 * MINUTES) +#define DAYS (24 * HOURS) +#define MONTHS (30 * DAYS) +#define YEARS (12 * MONTHS) + if (time >= YEARS) { + year = time / YEARS; + time -= year * YEARS; + + rv = snprintfrr(buf, buflen, "%" PRIu64 " year(s), ", year); + buf += rv; + buflen -= rv; + } + if (time >= MONTHS) { + month = time / MONTHS; + time -= month * MONTHS; + + rv = snprintfrr(buf, buflen, "%" PRIu64 " month(s), ", month); + buf += rv; + buflen -= rv; + } + if (time >= DAYS) { + day = time / DAYS; + time -= day * DAYS; + + rv = snprintfrr(buf, buflen, "%" PRIu64 " day(s), ", day); + buf += rv; + buflen -= rv; + } + if (time >= HOURS) { + hour = time / HOURS; + time -= hour * HOURS; + + rv = snprintfrr(buf, buflen, "%" PRIu64 " hour(s), ", hour); + buf += rv; + buflen -= rv; + } + if (time >= MINUTES) { + minute = time / MINUTES; + time -= minute * MINUTES; + + rv = snprintfrr(buf, buflen, "%" PRIu64 " minute(s), ", minute); + buf += rv; + buflen -= rv; + } + second = time % MINUTES; + snprintfrr(buf, buflen, "%" PRIu64 " second(s)", second); +} + +const char *bs_to_string(const struct bfd_session *bs) +{ + static char buf[256]; + char addr_buf[INET6_ADDRSTRLEN]; + int pos; + bool is_mhop = CHECK_FLAG(bs->flags, BFD_SESS_FLAG_MH); + + pos = snprintf(buf, sizeof(buf), "mhop:%s", is_mhop ? "yes" : "no"); + pos += snprintf(buf + pos, sizeof(buf) - pos, " peer:%s", + inet_ntop(bs->key.family, &bs->key.peer, addr_buf, + sizeof(addr_buf))); + pos += snprintf(buf + pos, sizeof(buf) - pos, " local:%s", + inet_ntop(bs->key.family, &bs->key.local, addr_buf, + sizeof(addr_buf))); + if (bs->key.vrfname[0]) + pos += snprintf(buf + pos, sizeof(buf) - pos, " vrf:%s", + bs->key.vrfname); + if (bs->key.ifname[0]) + pos += snprintf(buf + pos, sizeof(buf) - pos, " ifname:%s", + bs->key.ifname); + + (void)pos; + + return buf; +} + +int bs_observer_add(struct bfd_session *bs) +{ + struct bfd_session_observer *bso; + + bso = XCALLOC(MTYPE_BFDD_SESSION_OBSERVER, sizeof(*bso)); + bso->bso_bs = bs; + bso->bso_addr.family = bs->key.family; + memcpy(&bso->bso_addr.u.prefix, &bs->key.local, + sizeof(bs->key.local)); + + TAILQ_INSERT_TAIL(&bglobal.bg_obslist, bso, bso_entry); + + return 0; +} + +void bs_observer_del(struct bfd_session_observer *bso) +{ + TAILQ_REMOVE(&bglobal.bg_obslist, bso, bso_entry); + XFREE(MTYPE_BFDD_SESSION_OBSERVER, bso); +} + +void bs_to_bpc(struct bfd_session *bs, struct bfd_peer_cfg *bpc) +{ + memset(bpc, 0, sizeof(*bpc)); + + bpc->bpc_ipv4 = (bs->key.family == AF_INET); + bpc->bpc_mhop = bs->key.mhop; + + switch (bs->key.family) { + case AF_INET: + bpc->bpc_peer.sa_sin.sin_family = AF_INET; + memcpy(&bpc->bpc_peer.sa_sin.sin_addr, &bs->key.peer, + sizeof(bpc->bpc_peer.sa_sin.sin_addr)); + + if (memcmp(&bs->key.local, &zero_addr, sizeof(bs->key.local))) { + bpc->bpc_local.sa_sin.sin_family = AF_INET6; + memcpy(&bpc->bpc_local.sa_sin.sin_addr, &bs->key.local, + sizeof(bpc->bpc_local.sa_sin.sin_addr)); + } + break; + + case AF_INET6: + bpc->bpc_peer.sa_sin.sin_family = AF_INET6; + memcpy(&bpc->bpc_peer.sa_sin6.sin6_addr, &bs->key.peer, + sizeof(bpc->bpc_peer.sa_sin6.sin6_addr)); + + bpc->bpc_local.sa_sin6.sin6_family = AF_INET6; + memcpy(&bpc->bpc_local.sa_sin6.sin6_addr, &bs->key.local, + sizeof(bpc->bpc_local.sa_sin6.sin6_addr)); + break; + } + + if (bs->key.ifname[0]) { + bpc->bpc_has_localif = true; + strlcpy(bpc->bpc_localif, bs->key.ifname, + sizeof(bpc->bpc_localif)); + } + + if (bs->key.vrfname[0]) { + bpc->bpc_has_vrfname = true; + strlcpy(bpc->bpc_vrfname, bs->key.vrfname, + sizeof(bpc->bpc_vrfname)); + } +} + + +/* + * BFD hash data structures to find sessions. + */ +static struct hash *bfd_id_hash; +static struct hash *bfd_key_hash; + +static unsigned int bfd_id_hash_do(const void *p); +static unsigned int bfd_key_hash_do(const void *p); + +static void _bfd_free(struct hash_bucket *hb, + void *arg __attribute__((__unused__))); + +/* BFD hash for our discriminator. */ +static unsigned int bfd_id_hash_do(const void *p) +{ + const struct bfd_session *bs = p; + + return jhash_1word(bs->discrs.my_discr, 0); +} + +static bool bfd_id_hash_cmp(const void *n1, const void *n2) +{ + const struct bfd_session *bs1 = n1, *bs2 = n2; + + return bs1->discrs.my_discr == bs2->discrs.my_discr; +} + +/* BFD hash for single hop. */ +static unsigned int bfd_key_hash_do(const void *p) +{ + const struct bfd_session *bs = p; + struct bfd_key key = bs->key; + + /* + * Local address and interface name are optional and + * can be filled any time after session creation. + * Hash key should not depend on these fields. + */ + memset(&key.local, 0, sizeof(key.local)); + memset(key.ifname, 0, sizeof(key.ifname)); + + return jhash(&key, sizeof(key), 0); +} + +static bool bfd_key_hash_cmp(const void *n1, const void *n2) +{ + const struct bfd_session *bs1 = n1, *bs2 = n2; + + if (bs1->key.family != bs2->key.family) + return false; + if (bs1->key.mhop != bs2->key.mhop) + return false; + if (memcmp(&bs1->key.peer, &bs2->key.peer, sizeof(bs1->key.peer))) + return false; + if (memcmp(bs1->key.vrfname, bs2->key.vrfname, + sizeof(bs1->key.vrfname))) + return false; + + /* + * Local address is optional and can be empty. + * If both addresses are not empty and different, + * then the keys are different. + */ + if (memcmp(&bs1->key.local, &zero_addr, sizeof(bs1->key.local)) + && memcmp(&bs2->key.local, &zero_addr, sizeof(bs2->key.local)) + && memcmp(&bs1->key.local, &bs2->key.local, sizeof(bs1->key.local))) + return false; + + /* + * Interface name is optional and can be empty. + * If both names are not empty and different, + * then the keys are different. + */ + if (bs1->key.ifname[0] && bs2->key.ifname[0] + && memcmp(bs1->key.ifname, bs2->key.ifname, + sizeof(bs1->key.ifname))) + return false; + + return true; +} + + +/* + * Hash public interface / exported functions. + */ + +/* Lookup functions. */ +struct bfd_session *bfd_id_lookup(uint32_t id) +{ + struct bfd_session bs; + + bs.discrs.my_discr = id; + + return hash_lookup(bfd_id_hash, &bs); +} + +struct bfd_session *bfd_key_lookup(struct bfd_key key) +{ + struct bfd_session bs; + + bs.key = key; + + return hash_lookup(bfd_key_hash, &bs); +} + +/* + * Delete functions. + * + * Delete functions searches and remove the item from the hash and + * returns a pointer to the removed item data. If the item was not found + * then it returns NULL. + * + * The data stored inside the hash is not free()ed, so you must do it + * manually after getting the pointer back. + */ +struct bfd_session *bfd_id_delete(uint32_t id) +{ + struct bfd_session bs; + + bs.discrs.my_discr = id; + + return hash_release(bfd_id_hash, &bs); +} + +struct bfd_session *bfd_key_delete(struct bfd_key key) +{ + struct bfd_session bs; + + bs.key = key; + + return hash_release(bfd_key_hash, &bs); +} + +/* Iteration functions. */ +void bfd_id_iterate(hash_iter_func hif, void *arg) +{ + hash_iterate(bfd_id_hash, hif, arg); +} + +void bfd_key_iterate(hash_iter_func hif, void *arg) +{ + hash_iterate(bfd_key_hash, hif, arg); +} + +/* + * Insert functions. + * + * Inserts session into hash and returns `true` on success, otherwise + * `false`. + */ +bool bfd_id_insert(struct bfd_session *bs) +{ + return (hash_get(bfd_id_hash, bs, hash_alloc_intern) == bs); +} + +bool bfd_key_insert(struct bfd_session *bs) +{ + return (hash_get(bfd_key_hash, bs, hash_alloc_intern) == bs); +} + +void bfd_initialize(void) +{ + bfd_id_hash = hash_create(bfd_id_hash_do, bfd_id_hash_cmp, + "BFD session discriminator hash"); + bfd_key_hash = hash_create(bfd_key_hash_do, bfd_key_hash_cmp, + "BFD session hash"); + TAILQ_INIT(&bplist); +} + +static void _bfd_free(struct hash_bucket *hb, + void *arg __attribute__((__unused__))) +{ + struct bfd_session *bs = hb->data; + + bfd_session_free(bs); +} + +void bfd_shutdown(void) +{ + struct bfd_profile *bp; + + /* + * Close and free all BFD sessions. + * + * _bfd_free() will call bfd_session_free() which will take care + * of removing the session from all hashes, so we just run an + * assert() here to make sure it really happened. + */ + bfd_id_iterate(_bfd_free, NULL); + assert(bfd_key_hash->count == 0); + + /* Now free the hashes themselves. */ + hash_free(bfd_id_hash); + hash_free(bfd_key_hash); + + /* Free all profile allocations. */ + while ((bp = TAILQ_FIRST(&bplist)) != NULL) + bfd_profile_free(bp); +} + +struct bfd_session_iterator { + int bsi_stop; + bool bsi_mhop; + const struct bfd_session *bsi_bs; +}; + +static int _bfd_session_next(struct hash_bucket *hb, void *arg) +{ + struct bfd_session_iterator *bsi = arg; + struct bfd_session *bs = hb->data; + + /* Previous entry signaled stop. */ + if (bsi->bsi_stop == 1) { + /* Match the single/multi hop sessions. */ + if (bs->key.mhop != bsi->bsi_mhop) + return HASHWALK_CONTINUE; + + bsi->bsi_bs = bs; + return HASHWALK_ABORT; + } + + /* We found the current item, stop in the next one. */ + if (bsi->bsi_bs == hb->data) { + bsi->bsi_stop = 1; + /* Set entry to NULL to signal end of list. */ + bsi->bsi_bs = NULL; + } else if (bsi->bsi_bs == NULL && bsi->bsi_mhop == bs->key.mhop) { + /* We want the first list item. */ + bsi->bsi_stop = 1; + bsi->bsi_bs = hb->data; + return HASHWALK_ABORT; + } + + return HASHWALK_CONTINUE; +} + +/* + * bfd_session_next: uses the current session to find the next. + * + * `bs` might point to NULL to get the first item of the data structure. + */ +const struct bfd_session *bfd_session_next(const struct bfd_session *bs, + bool mhop) +{ + struct bfd_session_iterator bsi; + + bsi.bsi_stop = 0; + bsi.bsi_bs = bs; + bsi.bsi_mhop = mhop; + hash_walk(bfd_key_hash, _bfd_session_next, &bsi); + if (bsi.bsi_stop == 0) + return NULL; + + return bsi.bsi_bs; +} + +static void _bfd_session_remove_manual(struct hash_bucket *hb, + void *arg __attribute__((__unused__))) +{ + struct bfd_session *bs = hb->data; + + /* Delete only manually configured sessions. */ + if (CHECK_FLAG(bs->flags, BFD_SESS_FLAG_CONFIG) == 0) + return; + + bs->refcount--; + UNSET_FLAG(bs->flags, BFD_SESS_FLAG_CONFIG); + + /* Don't delete sessions still in use. */ + if (bs->refcount != 0) + return; + + bfd_session_free(bs); +} + +/* + * bfd_sessions_remove_manual: remove all manually configured sessions. + * + * NOTE: this function doesn't remove automatically created sessions. + */ +void bfd_sessions_remove_manual(void) +{ + hash_iterate(bfd_key_hash, _bfd_session_remove_manual, NULL); +} + +void bfd_profiles_remove(void) +{ + struct bfd_profile *bp; + + while ((bp = TAILQ_FIRST(&bplist)) != NULL) + bfd_profile_free(bp); +} + +/* + * Profile related hash functions. + */ +static void _bfd_profile_update(struct hash_bucket *hb, void *arg) +{ + struct bfd_profile *bp = arg; + struct bfd_session *bs = hb->data; + + /* This session is not using the profile. */ + if (bs->profile_name == NULL || strcmp(bs->profile_name, bp->name) != 0) + return; + + bfd_profile_apply(bp->name, bs); +} + +void bfd_profile_update(struct bfd_profile *bp) +{ + hash_iterate(bfd_key_hash, _bfd_profile_update, bp); +} + +static void _bfd_profile_detach(struct hash_bucket *hb, void *arg) +{ + struct bfd_profile *bp = arg; + struct bfd_session *bs = hb->data; + + /* This session is not using the profile. */ + if (bs->profile_name == NULL || strcmp(bs->profile_name, bp->name) != 0) + return; + + bfd_profile_remove(bs); +} + +static void bfd_profile_detach(struct bfd_profile *bp) +{ + hash_iterate(bfd_key_hash, _bfd_profile_detach, bp); +} + +/* + * VRF related functions. + */ +static int bfd_vrf_new(struct vrf *vrf) +{ + if (bglobal.debug_zebra) + zlog_debug("VRF Created: %s(%u)", vrf->name, vrf->vrf_id); + + return 0; +} + +static int bfd_vrf_delete(struct vrf *vrf) +{ + if (bglobal.debug_zebra) + zlog_debug("VRF Deletion: %s(%u)", vrf->name, vrf->vrf_id); + + return 0; +} + +static int bfd_vrf_enable(struct vrf *vrf) +{ + struct bfd_vrf_global *bvrf; + + /* a different name */ + if (!vrf->info) { + bvrf = XCALLOC(MTYPE_BFDD_VRF, sizeof(struct bfd_vrf_global)); + bvrf->vrf = vrf; + vrf->info = (void *)bvrf; + + /* Disable sockets if using data plane. */ + if (bglobal.bg_use_dplane) { + bvrf->bg_shop = -1; + bvrf->bg_mhop = -1; + bvrf->bg_shop6 = -1; + bvrf->bg_mhop6 = -1; + bvrf->bg_echo = -1; + bvrf->bg_echov6 = -1; + } + } else + bvrf = vrf->info; + + if (bglobal.debug_zebra) + zlog_debug("VRF enable add %s id %u", vrf->name, vrf->vrf_id); + + if (!bvrf->bg_shop) + bvrf->bg_shop = bp_udp_shop(vrf); + if (!bvrf->bg_mhop) + bvrf->bg_mhop = bp_udp_mhop(vrf); + if (!bvrf->bg_shop6) + bvrf->bg_shop6 = bp_udp6_shop(vrf); + if (!bvrf->bg_mhop6) + bvrf->bg_mhop6 = bp_udp6_mhop(vrf); + if (!bvrf->bg_echo) + bvrf->bg_echo = bp_echo_socket(vrf); + if (!bvrf->bg_echov6) + bvrf->bg_echov6 = bp_echov6_socket(vrf); + + if (!bvrf->bg_ev[0] && bvrf->bg_shop != -1) + event_add_read(master, bfd_recv_cb, bvrf, bvrf->bg_shop, + &bvrf->bg_ev[0]); + if (!bvrf->bg_ev[1] && bvrf->bg_mhop != -1) + event_add_read(master, bfd_recv_cb, bvrf, bvrf->bg_mhop, + &bvrf->bg_ev[1]); + if (!bvrf->bg_ev[2] && bvrf->bg_shop6 != -1) + event_add_read(master, bfd_recv_cb, bvrf, bvrf->bg_shop6, + &bvrf->bg_ev[2]); + if (!bvrf->bg_ev[3] && bvrf->bg_mhop6 != -1) + event_add_read(master, bfd_recv_cb, bvrf, bvrf->bg_mhop6, + &bvrf->bg_ev[3]); + if (!bvrf->bg_ev[4] && bvrf->bg_echo != -1) + event_add_read(master, bfd_recv_cb, bvrf, bvrf->bg_echo, + &bvrf->bg_ev[4]); + if (!bvrf->bg_ev[5] && bvrf->bg_echov6 != -1) + event_add_read(master, bfd_recv_cb, bvrf, bvrf->bg_echov6, + &bvrf->bg_ev[5]); + + if (vrf->vrf_id != VRF_DEFAULT) { + bfdd_zclient_register(vrf->vrf_id); + bfdd_sessions_enable_vrf(vrf); + } + return 0; +} + +static int bfd_vrf_disable(struct vrf *vrf) +{ + struct bfd_vrf_global *bvrf; + + if (!vrf->info) + return 0; + bvrf = vrf->info; + + if (vrf->vrf_id != VRF_DEFAULT) { + bfdd_sessions_disable_vrf(vrf); + bfdd_zclient_unregister(vrf->vrf_id); + } + + if (bglobal.debug_zebra) + zlog_debug("VRF disable %s id %d", vrf->name, vrf->vrf_id); + + /* Disable read/write poll triggering. */ + EVENT_OFF(bvrf->bg_ev[0]); + EVENT_OFF(bvrf->bg_ev[1]); + EVENT_OFF(bvrf->bg_ev[2]); + EVENT_OFF(bvrf->bg_ev[3]); + EVENT_OFF(bvrf->bg_ev[4]); + EVENT_OFF(bvrf->bg_ev[5]); + + /* Close all descriptors. */ + socket_close(&bvrf->bg_echo); + socket_close(&bvrf->bg_shop); + socket_close(&bvrf->bg_mhop); + if (bvrf->bg_shop6 != -1) + socket_close(&bvrf->bg_shop6); + if (bvrf->bg_mhop6 != -1) + socket_close(&bvrf->bg_mhop6); + socket_close(&bvrf->bg_echo); + if (bvrf->bg_echov6 != -1) + socket_close(&bvrf->bg_echov6); + + /* free context */ + XFREE(MTYPE_BFDD_VRF, bvrf); + vrf->info = NULL; + + return 0; +} + +void bfd_vrf_init(void) +{ + vrf_init(bfd_vrf_new, bfd_vrf_enable, bfd_vrf_disable, bfd_vrf_delete); +} + +void bfd_vrf_terminate(void) +{ + vrf_terminate(); +} + +struct bfd_vrf_global *bfd_vrf_look_by_session(struct bfd_session *bfd) +{ + struct vrf *vrf; + + if (!vrf_is_backend_netns()) { + vrf = vrf_lookup_by_id(VRF_DEFAULT); + if (vrf) + return (struct bfd_vrf_global *)vrf->info; + return NULL; + } + if (!bfd) + return NULL; + if (!bfd->vrf) + return NULL; + return bfd->vrf->info; +} + +unsigned long bfd_get_session_count(void) +{ + return bfd_key_hash->count; +} + +void bfd_rtt_init(struct bfd_session *bfd) +{ + uint8_t i; + + /* initialize RTT */ + bfd->rtt_valid = 0; + bfd->rtt_index = 0; + for (i = 0; i < BFD_RTT_SAMPLE; i++) + bfd->rtt[i] = 0; +} |