diff options
Diffstat (limited to 'src/daemon/event.c')
| -rw-r--r-- | src/daemon/event.c | 911 |
1 files changed, 911 insertions, 0 deletions
diff --git a/src/daemon/event.c b/src/daemon/event.c new file mode 100644 index 0000000..971500f --- /dev/null +++ b/src/daemon/event.c @@ -0,0 +1,911 @@ +/* -*- mode: c; c-file-style: "openbsd" -*- */ +/* + * Copyright (c) 2012 Vincent Bernat <bernat@luffy.cx> + * + * Permission to use, copy, modify, and/or distribute this software for any + * purpose with or without fee is hereby granted, provided that the above + * copyright notice and this permission notice appear in all copies. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES + * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR + * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES + * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN + * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF + * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. + */ + +#include "lldpd.h" +#include "trace.h" + +#include <unistd.h> +#include <signal.h> +#include <errno.h> +#include <time.h> +#include <fcntl.h> +#if defined(__clang__) +# pragma clang diagnostic push +# pragma clang diagnostic ignored "-Wdocumentation" +#endif +#include <event2/event.h> +#include <event2/bufferevent.h> +#include <event2/buffer.h> +#if defined(__clang__) +# pragma clang diagnostic pop +#endif + +#define EVENT_BUFFER 1024 + +static void +levent_log_cb(int severity, const char *msg) +{ + switch (severity) { + case _EVENT_LOG_DEBUG: + log_debug("libevent", "%s", msg); + break; + case _EVENT_LOG_MSG: + log_info("libevent", "%s", msg); + break; + case _EVENT_LOG_WARN: + log_warnx("libevent", "%s", msg); + break; + case _EVENT_LOG_ERR: + log_warnx("libevent", "%s", msg); + break; + } +} + +struct lldpd_events { + TAILQ_ENTRY(lldpd_events) next; + struct event *ev; +}; +TAILQ_HEAD(ev_l, lldpd_events); + +#define levent_snmp_fds(cfg) ((struct ev_l *)(cfg)->g_snmp_fds) +#define levent_hardware_fds(hardware) ((struct ev_l *)(hardware)->h_recv) + +#ifdef USE_SNMP +# include <net-snmp/net-snmp-config.h> +# include <net-snmp/net-snmp-includes.h> +# include <net-snmp/agent/net-snmp-agent-includes.h> +# include <net-snmp/agent/snmp_vars.h> + +/* Compatibility with older versions of NetSNMP */ +# ifndef HAVE_SNMP_SELECT_INFO2 +# define netsnmp_large_fd_set fd_set +# define snmp_read2 snmp_read +# define snmp_select_info2 snmp_select_info +# define netsnmp_large_fd_set_init(...) +# define netsnmp_large_fd_set_cleanup(...) +# define NETSNMP_LARGE_FD_SET FD_SET +# define NETSNMP_LARGE_FD_CLR FD_CLR +# define NETSNMP_LARGE_FD_ZERO FD_ZERO +# define NETSNMP_LARGE_FD_ISSET FD_ISSET +# else +# include <net-snmp/library/large_fd_set.h> +# endif + +static void levent_snmp_update(struct lldpd *); + +/* + * Callback function when we have something to read from SNMP. + * + * This function is called because we have a read event on one SNMP + * file descriptor. When need to call snmp_read() on it. + */ +static void +levent_snmp_read(evutil_socket_t fd, short what, void *arg) +{ + struct lldpd *cfg = arg; + netsnmp_large_fd_set fdset; + (void)what; + netsnmp_large_fd_set_init(&fdset, FD_SETSIZE); + NETSNMP_LARGE_FD_ZERO(&fdset); + NETSNMP_LARGE_FD_SET(fd, &fdset); + snmp_read2(&fdset); + levent_snmp_update(cfg); +} + +/* + * Callback function for a SNMP timeout. + * + * A SNMP timeout has occurred. Call `snmp_timeout()` to handle it. + */ +static void +levent_snmp_timeout(evutil_socket_t fd, short what, void *arg) +{ + struct lldpd *cfg = arg; + (void)what; + (void)fd; + snmp_timeout(); + run_alarms(); + levent_snmp_update(cfg); +} + +/* + * Watch a new SNMP FD. + * + * @param base The libevent base we are working on. + * @param fd The file descriptor we want to watch. + * + * The file descriptor is appended to the list of file descriptors we + * want to watch. + */ +static void +levent_snmp_add_fd(struct lldpd *cfg, int fd) +{ + struct event_base *base = cfg->g_base; + struct lldpd_events *snmpfd = calloc(1, sizeof(struct lldpd_events)); + if (!snmpfd) { + log_warn("event", "unable to allocate memory for new SNMP event"); + return; + } + levent_make_socket_nonblocking(fd); + if ((snmpfd->ev = event_new(base, fd, EV_READ | EV_PERSIST, levent_snmp_read, + cfg)) == NULL) { + log_warnx("event", "unable to allocate a new SNMP event for FD %d", fd); + free(snmpfd); + return; + } + if (event_add(snmpfd->ev, NULL) == -1) { + log_warnx("event", "unable to schedule new SNMP event for FD %d", fd); + event_free(snmpfd->ev); + free(snmpfd); + return; + } + TAILQ_INSERT_TAIL(levent_snmp_fds(cfg), snmpfd, next); +} + +/* + * Update SNMP event loop. + * + * New events are added and some other are removed. This function + * should be called every time a SNMP event happens: either when + * handling a SNMP packet, a SNMP timeout or when sending a SNMP + * packet. This function will keep libevent in sync with NetSNMP. + * + * @param base The libevent base we are working on. + */ +static void +levent_snmp_update(struct lldpd *cfg) +{ + int maxfd = 0; + int block = 1; + struct timeval timeout; + static int howmany = 0; + int added = 0, removed = 0, current = 0; + struct lldpd_events *snmpfd, *snmpfd_next; + + /* snmp_select_info() can be tricky to understand. We set `block` to + 1 to means that we don't request a timeout. snmp_select_info() + will reset `block` to 0 if it wants us to setup a timeout. In + this timeout, `snmp_timeout()` should be invoked. + + Each FD in `fdset` will need to be watched for reading. If one of + them become active, `snmp_read()` should be called on it. + */ + + netsnmp_large_fd_set fdset; + netsnmp_large_fd_set_init(&fdset, FD_SETSIZE); + NETSNMP_LARGE_FD_ZERO(&fdset); + snmp_select_info2(&maxfd, &fdset, &timeout, &block); + + /* We need to untrack any event whose FD is not in `fdset` + anymore */ + for (snmpfd = TAILQ_FIRST(levent_snmp_fds(cfg)); snmpfd; snmpfd = snmpfd_next) { + snmpfd_next = TAILQ_NEXT(snmpfd, next); + if (event_get_fd(snmpfd->ev) >= maxfd || + (!NETSNMP_LARGE_FD_ISSET(event_get_fd(snmpfd->ev), &fdset))) { + event_free(snmpfd->ev); + TAILQ_REMOVE(levent_snmp_fds(cfg), snmpfd, next); + free(snmpfd); + removed++; + } else { + NETSNMP_LARGE_FD_CLR(event_get_fd(snmpfd->ev), &fdset); + current++; + } + } + + /* Invariant: FD in `fdset` are not in list of FD */ + for (int fd = 0; fd < maxfd; fd++) { + if (NETSNMP_LARGE_FD_ISSET(fd, &fdset)) { + levent_snmp_add_fd(cfg, fd); + added++; + } + } + current += added; + if (howmany != current) { + log_debug("event", + "added %d events, removed %d events, total of %d events", added, + removed, current); + howmany = current; + } + + /* If needed, handle timeout */ + if (evtimer_add(cfg->g_snmp_timeout, block ? NULL : &timeout) == -1) + log_warnx("event", "unable to schedule timeout function for SNMP"); + + netsnmp_large_fd_set_cleanup(&fdset); +} +#endif /* USE_SNMP */ + +struct lldpd_one_client { + TAILQ_ENTRY(lldpd_one_client) next; + struct lldpd *cfg; + struct bufferevent *bev; + int subscribed; /* Is this client subscribed to changes? */ +}; +TAILQ_HEAD(, lldpd_one_client) lldpd_clients; + +static void +levent_ctl_free_client(struct lldpd_one_client *client) +{ + if (client && client->bev) bufferevent_free(client->bev); + if (client) { + TAILQ_REMOVE(&lldpd_clients, client, next); + free(client); + } +} + +static void +levent_ctl_close_clients() +{ + struct lldpd_one_client *client, *client_next; + for (client = TAILQ_FIRST(&lldpd_clients); client; client = client_next) { + client_next = TAILQ_NEXT(client, next); + levent_ctl_free_client(client); + } +} + +static ssize_t +levent_ctl_send(struct lldpd_one_client *client, int type, void *data, size_t len) +{ + struct bufferevent *bev = client->bev; + struct hmsg_header hdr = { .len = len, .type = type }; + bufferevent_disable(bev, EV_WRITE); + if (bufferevent_write(bev, &hdr, sizeof(struct hmsg_header)) == -1 || + (len > 0 && bufferevent_write(bev, data, len) == -1)) { + log_warnx("event", "unable to create answer to client"); + levent_ctl_free_client(client); + return -1; + } + bufferevent_enable(bev, EV_WRITE); + return len; +} + +void +levent_ctl_notify(char *ifname, int state, struct lldpd_port *neighbor) +{ + struct lldpd_one_client *client, *client_next; + struct lldpd_neighbor_change neigh = { .ifname = ifname, + .state = state, + .neighbor = neighbor }; + void *output = NULL; + ssize_t output_len = 0; + + /* Don't use TAILQ_FOREACH, the client may be deleted in case of errors. */ + log_debug("control", "notify clients of neighbor changes"); + for (client = TAILQ_FIRST(&lldpd_clients); client; client = client_next) { + client_next = TAILQ_NEXT(client, next); + if (!client->subscribed) continue; + + if (output == NULL) { + /* Ugly hack: we don't want to transmit a list of + * ports. We patch the port to avoid this. */ + TAILQ_ENTRY(lldpd_port) backup_p_entries; + memcpy(&backup_p_entries, &neighbor->p_entries, + sizeof(backup_p_entries)); + memset(&neighbor->p_entries, 0, sizeof(backup_p_entries)); + output_len = lldpd_neighbor_change_serialize(&neigh, &output); + memcpy(&neighbor->p_entries, &backup_p_entries, + sizeof(backup_p_entries)); + + if (output_len <= 0) { + log_warnx("event", + "unable to serialize changed neighbor"); + return; + } + } + + levent_ctl_send(client, NOTIFICATION, output, output_len); + } + + free(output); +} + +static ssize_t +levent_ctl_send_cb(void *out, int type, void *data, size_t len) +{ + struct lldpd_one_client *client = out; + return levent_ctl_send(client, type, data, len); +} + +static void +levent_ctl_recv(struct bufferevent *bev, void *ptr) +{ + struct lldpd_one_client *client = ptr; + struct evbuffer *buffer = bufferevent_get_input(bev); + size_t buffer_len = evbuffer_get_length(buffer); + struct hmsg_header hdr; + void *data = NULL; + + log_debug("control", "receive data on Unix socket"); + if (buffer_len < sizeof(struct hmsg_header)) return; /* Not enough data yet */ + if (evbuffer_copyout(buffer, &hdr, sizeof(struct hmsg_header)) != + sizeof(struct hmsg_header)) { + log_warnx("event", "not able to read header"); + return; + } + if (hdr.len > HMSG_MAX_SIZE) { + log_warnx("event", "message received is too large"); + goto recv_error; + } + + if (buffer_len < hdr.len + sizeof(struct hmsg_header)) + return; /* Not enough data yet */ + if (hdr.len > 0 && (data = malloc(hdr.len)) == NULL) { + log_warnx("event", "not enough memory"); + goto recv_error; + } + evbuffer_drain(buffer, sizeof(struct hmsg_header)); + if (hdr.len > 0) evbuffer_remove(buffer, data, hdr.len); + + /* Currently, we should not receive notification acknowledgment. But if + * we receive one, we can discard it. */ + if (hdr.len == 0 && hdr.type == NOTIFICATION) return; + if (client_handle_client(client->cfg, levent_ctl_send_cb, client, hdr.type, + data, hdr.len, &client->subscribed) == -1) + goto recv_error; + free(data); + return; + +recv_error: + free(data); + levent_ctl_free_client(client); +} + +static void +levent_ctl_event(struct bufferevent *bev, short events, void *ptr) +{ + struct lldpd_one_client *client = ptr; + if (events & BEV_EVENT_ERROR) { + log_warnx("event", "an error occurred with client: %s", + evutil_socket_error_to_string(EVUTIL_SOCKET_ERROR())); + levent_ctl_free_client(client); + } else if (events & BEV_EVENT_EOF) { + log_debug("event", "client has been disconnected"); + levent_ctl_free_client(client); + } +} + +static void +levent_ctl_accept(evutil_socket_t fd, short what, void *arg) +{ + struct lldpd *cfg = arg; + struct lldpd_one_client *client = NULL; + int s; + (void)what; + + log_debug("control", "accept a new connection"); + if ((s = accept(fd, NULL, NULL)) == -1) { + log_warn("event", "unable to accept connection from socket"); + return; + } + client = calloc(1, sizeof(struct lldpd_one_client)); + if (!client) { + log_warnx("event", "unable to allocate memory for new client"); + close(s); + goto accept_failed; + } + client->cfg = cfg; + levent_make_socket_nonblocking(s); + TAILQ_INSERT_TAIL(&lldpd_clients, client, next); + if ((client->bev = bufferevent_socket_new(cfg->g_base, s, + BEV_OPT_CLOSE_ON_FREE)) == NULL) { + log_warnx("event", + "unable to allocate a new buffer event for new client"); + close(s); + goto accept_failed; + } + bufferevent_setcb(client->bev, levent_ctl_recv, NULL, levent_ctl_event, client); + bufferevent_enable(client->bev, EV_READ | EV_WRITE); + log_debug("event", "new client accepted"); + /* coverity[leaked_handle] + s has been saved by bufferevent_socket_new */ + return; +accept_failed: + levent_ctl_free_client(client); +} + +static void +levent_priv(evutil_socket_t fd, short what, void *arg) +{ + struct event_base *base = arg; + ssize_t n; + int err; + char one; + (void)what; + /* Check if we have some data available. We need to pass the socket in + * non-blocking mode to be able to run the check without disruption. */ + levent_make_socket_nonblocking(fd); + n = read(fd, &one, 1); + err = errno; + levent_make_socket_blocking(fd); + + switch (n) { + case -1: + if (err == EAGAIN || err == EWOULDBLOCK) /* No data, all good */ + return; + log_warnx("event", "unable to poll monitor process, exit"); + break; + case 0: + log_warnx("event", "monitor process has terminated, exit"); + break; + default: + /* This is a bit unsafe as we are now out-of-sync with the + * monitor. It would be safer to request 0 byte, but some OS + * (illumos) seem to take the shortcut that by asking 0 byte, + * we can just return 0 byte. */ + log_warnx("event", + "received unexpected data from monitor process, exit"); + break; + } + event_base_loopbreak(base); +} + +static void +levent_dump(evutil_socket_t fd, short what, void *arg) +{ + struct event_base *base = arg; + (void)fd; + (void)what; + log_debug("event", "dumping all events"); + event_base_dump_events(base, stderr); +} +static void +levent_stop(evutil_socket_t fd, short what, void *arg) +{ + struct event_base *base = arg; + (void)fd; + (void)what; + event_base_loopbreak(base); +} + +static void +levent_update_and_send(evutil_socket_t fd, short what, void *arg) +{ + struct lldpd *cfg = arg; + struct timeval tv; + long interval_ms = cfg->g_config.c_tx_interval; + + (void)fd; + (void)what; + lldpd_loop(cfg); + if (cfg->g_iface_event != NULL) interval_ms *= 20; + if (interval_ms < 30000) interval_ms = 30000; + tv.tv_sec = interval_ms / 1000; + tv.tv_usec = (interval_ms % 1000) * 1000; + event_add(cfg->g_main_loop, &tv); +} + +void +levent_update_now(struct lldpd *cfg) +{ + if (cfg->g_main_loop) event_active(cfg->g_main_loop, EV_TIMEOUT, 1); +} + +void +levent_send_now(struct lldpd *cfg) +{ + struct lldpd_hardware *hardware; + TAILQ_FOREACH (hardware, &cfg->g_hardware, h_entries) { + if (hardware->h_timer) + event_active(hardware->h_timer, EV_TIMEOUT, 1); + else + log_warnx("event", "BUG: no timer present for interface %s", + hardware->h_ifname); + } +} + +static void +levent_init(struct lldpd *cfg) +{ + /* Setup libevent */ + log_debug("event", "initialize libevent"); + event_set_log_callback(levent_log_cb); + if (!(cfg->g_base = event_base_new())) + fatalx("event", "unable to create a new libevent base"); + log_info("event", "libevent %s initialized with %s method", event_get_version(), + event_base_get_method(cfg->g_base)); + + /* Setup SNMP */ +#ifdef USE_SNMP + if (cfg->g_snmp) { + agent_init(cfg, cfg->g_snmp_agentx); + cfg->g_snmp_timeout = + evtimer_new(cfg->g_base, levent_snmp_timeout, cfg); + if (!cfg->g_snmp_timeout) + fatalx("event", "unable to setup timeout function for SNMP"); + if ((cfg->g_snmp_fds = malloc(sizeof(struct ev_l))) == NULL) + fatalx("event", "unable to allocate memory for SNMP events"); + TAILQ_INIT(levent_snmp_fds(cfg)); + } +#endif + + /* Setup loop that will run every X seconds. */ + log_debug("event", "register loop timer"); + if (!(cfg->g_main_loop = + event_new(cfg->g_base, -1, 0, levent_update_and_send, cfg))) + fatalx("event", "unable to setup main timer"); + event_active(cfg->g_main_loop, EV_TIMEOUT, 1); + + /* Setup unix socket */ + struct event *ctl_event; + log_debug("event", "register Unix socket"); + TAILQ_INIT(&lldpd_clients); + levent_make_socket_nonblocking(cfg->g_ctl); + if ((ctl_event = event_new(cfg->g_base, cfg->g_ctl, EV_READ | EV_PERSIST, + levent_ctl_accept, cfg)) == NULL) + fatalx("event", "unable to setup control socket event"); + event_add(ctl_event, NULL); + + /* Somehow monitor the monitor process */ + struct event *monitor_event; + log_debug("event", "monitor the monitor process"); + if ((monitor_event = event_new(cfg->g_base, priv_fd(PRIV_UNPRIVILEGED), + EV_READ | EV_PERSIST, levent_priv, cfg->g_base)) == NULL) + fatalx("event", "unable to monitor monitor process"); + event_add(monitor_event, NULL); + + /* Signals */ + log_debug("event", "register signals"); + evsignal_add(evsignal_new(cfg->g_base, SIGUSR1, levent_dump, cfg->g_base), + NULL); + evsignal_add(evsignal_new(cfg->g_base, SIGINT, levent_stop, cfg->g_base), NULL); + evsignal_add(evsignal_new(cfg->g_base, SIGTERM, levent_stop, cfg->g_base), + NULL); +} + +/* Initialize libevent and start the event loop */ +void +levent_loop(struct lldpd *cfg) +{ + levent_init(cfg); + lldpd_loop(cfg); +#ifdef USE_SNMP + if (cfg->g_snmp) levent_snmp_update(cfg); +#endif + + /* libevent loop */ + do { + TRACE(LLDPD_EVENT_LOOP()); + if (event_base_got_break(cfg->g_base) || + event_base_got_exit(cfg->g_base)) + break; + } while (event_base_loop(cfg->g_base, EVLOOP_ONCE) == 0); + + if (cfg->g_iface_timer_event != NULL) event_free(cfg->g_iface_timer_event); + +#ifdef USE_SNMP + if (cfg->g_snmp) agent_shutdown(); +#endif /* USE_SNMP */ + + levent_ctl_close_clients(); +} + +/* Release libevent resources */ +void +levent_shutdown(struct lldpd *cfg) +{ + if (cfg->g_iface_event) event_free(cfg->g_iface_event); + if (cfg->g_cleanup_timer) event_free(cfg->g_cleanup_timer); + event_base_free(cfg->g_base); +} + +static void +levent_hardware_recv(evutil_socket_t fd, short what, void *arg) +{ + struct lldpd_hardware *hardware = arg; + struct lldpd *cfg = hardware->h_cfg; + (void)what; + log_debug("event", "received something for %s", hardware->h_ifname); + lldpd_recv(cfg, hardware, fd); + levent_schedule_cleanup(cfg); +} + +void +levent_hardware_init(struct lldpd_hardware *hardware) +{ + log_debug("event", "initialize events for %s", hardware->h_ifname); + if ((hardware->h_recv = malloc(sizeof(struct ev_l))) == NULL) { + log_warnx("event", "unable to allocate memory for %s", + hardware->h_ifname); + return; + } + TAILQ_INIT(levent_hardware_fds(hardware)); +} + +void +levent_hardware_add_fd(struct lldpd_hardware *hardware, int fd) +{ + struct lldpd_events *hfd = NULL; + if (!hardware->h_recv) return; + + hfd = calloc(1, sizeof(struct lldpd_events)); + if (!hfd) { + log_warnx("event", "unable to allocate new event for %s", + hardware->h_ifname); + return; + } + levent_make_socket_nonblocking(fd); + if ((hfd->ev = event_new(hardware->h_cfg->g_base, fd, EV_READ | EV_PERSIST, + levent_hardware_recv, hardware)) == NULL) { + log_warnx("event", "unable to allocate a new event for %s", + hardware->h_ifname); + free(hfd); + return; + } + if (event_add(hfd->ev, NULL) == -1) { + log_warnx("event", "unable to schedule new event for %s", + hardware->h_ifname); + event_free(hfd->ev); + free(hfd); + return; + } + TAILQ_INSERT_TAIL(levent_hardware_fds(hardware), hfd, next); +} + +void +levent_hardware_release(struct lldpd_hardware *hardware) +{ + struct lldpd_events *ev, *ev_next; + if (hardware->h_timer) { + event_free(hardware->h_timer); + hardware->h_timer = NULL; + } + if (!hardware->h_recv) return; + + log_debug("event", "release events for %s", hardware->h_ifname); + for (ev = TAILQ_FIRST(levent_hardware_fds(hardware)); ev; ev = ev_next) { + ev_next = TAILQ_NEXT(ev, next); + /* We may close several time the same FD. This is harmless. */ + close(event_get_fd(ev->ev)); + event_free(ev->ev); + TAILQ_REMOVE(levent_hardware_fds(hardware), ev, next); + free(ev); + } + free(levent_hardware_fds(hardware)); +} + +static void +levent_iface_trigger(evutil_socket_t fd, short what, void *arg) +{ + struct lldpd *cfg = arg; + log_debug("event", "triggering update of all interfaces"); + lldpd_update_localports(cfg); +} + +static void +levent_iface_recv(evutil_socket_t fd, short what, void *arg) +{ + struct lldpd *cfg = arg; + char buffer[EVENT_BUFFER]; + int n; + + if (cfg->g_iface_cb == NULL) { + /* Discard the message */ + while (1) { + n = read(fd, buffer, sizeof(buffer)); + if (n == -1 && (errno == EWOULDBLOCK || errno == EAGAIN)) break; + if (n == -1) { + log_warn("event", + "unable to receive interface change notification message"); + return; + } + if (n == 0) { + log_warnx("event", + "end of file reached while getting interface change notification message"); + return; + } + } + } else { + cfg->g_iface_cb(cfg); + } + + /* Schedule local port update. We don't run it right away because we may + * receive a batch of events like this. */ + struct timeval one_sec = { 1, 0 }; + TRACE(LLDPD_INTERFACES_NOTIFICATION()); + log_debug("event", + "received notification change, schedule an update of all interfaces in one second"); + if (cfg->g_iface_timer_event == NULL) { + if ((cfg->g_iface_timer_event = evtimer_new(cfg->g_base, + levent_iface_trigger, cfg)) == NULL) { + log_warnx("event", + "unable to create a new event to trigger interface update"); + return; + } + } + if (evtimer_add(cfg->g_iface_timer_event, &one_sec) == -1) { + log_warnx("event", "unable to schedule interface updates"); + return; + } +} + +int +levent_iface_subscribe(struct lldpd *cfg, int socket) +{ + log_debug("event", "subscribe to interface changes from socket %d", socket); + levent_make_socket_nonblocking(socket); + cfg->g_iface_event = event_new(cfg->g_base, socket, EV_READ | EV_PERSIST, + levent_iface_recv, cfg); + if (cfg->g_iface_event == NULL) { + log_warnx("event", + "unable to allocate a new event for interface changes"); + return -1; + } + if (event_add(cfg->g_iface_event, NULL) == -1) { + log_warnx("event", "unable to schedule new interface changes event"); + event_free(cfg->g_iface_event); + cfg->g_iface_event = NULL; + return -1; + } + return 0; +} + +static void +levent_trigger_cleanup(evutil_socket_t fd, short what, void *arg) +{ + struct lldpd *cfg = arg; + lldpd_cleanup(cfg); +} + +void +levent_schedule_cleanup(struct lldpd *cfg) +{ + log_debug("event", "schedule next cleanup"); + if (cfg->g_cleanup_timer != NULL) { + event_free(cfg->g_cleanup_timer); + } + cfg->g_cleanup_timer = evtimer_new(cfg->g_base, levent_trigger_cleanup, cfg); + if (cfg->g_cleanup_timer == NULL) { + log_warnx("event", "unable to allocate a new event for cleanup tasks"); + return; + } + + /* Compute the next TTL event */ + struct timeval tv = { cfg->g_config.c_ttl, 0 }; + time_t now = time(NULL); + time_t next; + struct lldpd_hardware *hardware; + struct lldpd_port *port; + TAILQ_FOREACH (hardware, &cfg->g_hardware, h_entries) { + TAILQ_FOREACH (port, &hardware->h_rports, p_entries) { + if (now >= port->p_lastupdate + port->p_ttl) { + tv.tv_sec = 0; + log_debug("event", + "immediate cleanup on port %s (%lld, %d, %lld)", + hardware->h_ifname, (long long)now, port->p_ttl, + (long long)port->p_lastupdate); + break; + } + next = port->p_ttl - (now - port->p_lastupdate); + if (next < tv.tv_sec) tv.tv_sec = next; + } + } + + log_debug("event", "next cleanup in %ld seconds", (long)tv.tv_sec); + if (event_add(cfg->g_cleanup_timer, &tv) == -1) { + log_warnx("event", "unable to schedule cleanup task"); + event_free(cfg->g_cleanup_timer); + cfg->g_cleanup_timer = NULL; + return; + } +} + +static void +levent_send_pdu(evutil_socket_t fd, short what, void *arg) +{ + struct lldpd_hardware *hardware = arg; + int tx_interval = hardware->h_cfg->g_config.c_tx_interval; + + log_debug("event", "trigger sending PDU for port %s", hardware->h_ifname); + lldpd_send(hardware); + +#ifdef ENABLE_LLDPMED + if (hardware->h_tx_fast > 0) hardware->h_tx_fast--; + + if (hardware->h_tx_fast > 0) + tx_interval = hardware->h_cfg->g_config.c_tx_fast_interval * 1000; +#endif + + struct timeval tv; + tv.tv_sec = tx_interval / 1000; + tv.tv_usec = (tx_interval % 1000) * 1000; + if (event_add(hardware->h_timer, &tv) == -1) { + log_warnx("event", "unable to re-register timer event for port %s", + hardware->h_ifname); + event_free(hardware->h_timer); + hardware->h_timer = NULL; + return; + } +} + +void +levent_schedule_pdu(struct lldpd_hardware *hardware) +{ + log_debug("event", "schedule sending PDU on %s", hardware->h_ifname); + if (hardware->h_timer == NULL) { + hardware->h_timer = + evtimer_new(hardware->h_cfg->g_base, levent_send_pdu, hardware); + if (hardware->h_timer == NULL) { + log_warnx("event", "unable to schedule PDU sending for port %s", + hardware->h_ifname); + return; + } + } + + struct timeval tv = { 0, 0 }; + if (event_add(hardware->h_timer, &tv) == -1) { + log_warnx("event", "unable to register timer event for port %s", + hardware->h_ifname); + event_free(hardware->h_timer); + hardware->h_timer = NULL; + return; + } +} + +int +levent_make_socket_nonblocking(int fd) +{ + int flags; + if ((flags = fcntl(fd, F_GETFL, NULL)) < 0) { + log_warn("event", "fcntl(%d, F_GETFL)", fd); + return -1; + } + if (flags & O_NONBLOCK) return 0; + if (fcntl(fd, F_SETFL, flags | O_NONBLOCK) == -1) { + log_warn("event", "fcntl(%d, F_SETFL)", fd); + return -1; + } + return 0; +} + +int +levent_make_socket_blocking(int fd) +{ + int flags; + if ((flags = fcntl(fd, F_GETFL, NULL)) < 0) { + log_warn("event", "fcntl(%d, F_GETFL)", fd); + return -1; + } + if (!(flags & O_NONBLOCK)) return 0; + if (fcntl(fd, F_SETFL, flags & ~O_NONBLOCK) == -1) { + log_warn("event", "fcntl(%d, F_SETFL)", fd); + return -1; + } + return 0; +} + +#ifdef HOST_OS_LINUX +/* Receive and log error from a socket when there is suspicion of an error. */ +void +levent_recv_error(int fd, const char *source) +{ + do { + ssize_t n; + char buf[1024] = {}; + struct msghdr msg = { .msg_control = buf, + .msg_controllen = sizeof(buf) }; + if ((n = recvmsg(fd, &msg, MSG_ERRQUEUE | MSG_DONTWAIT)) <= 0) { + return; + } + struct cmsghdr *cmsg = CMSG_FIRSTHDR(&msg); + if (cmsg == NULL) + log_warnx("event", "received unknown error on %s", source); + else + log_warnx("event", "received error (level=%d/type=%d) on %s", + cmsg->cmsg_level, cmsg->cmsg_type, source); + } while (1); +} +#endif |