// SPDX-License-Identifier: GPL-2.0-or-later /* * BFD data plane implementation (distributed BFD). * * Copyright (C) 2020 Network Device Education Foundation, Inc. ("NetDEF") * Rafael Zalamena */ #include #include #include #include #include #ifdef __FreeBSD__ #include #else #include #endif /* __FreeBSD__ */ #include #include #include "lib/hook.h" #include "lib/network.h" #include "lib/printfrr.h" #include "lib/stream.h" #include "lib/frrevent.h" #include "bfd.h" #include "bfddp_packet.h" #include "lib/openbsd-queue.h" DEFINE_MTYPE_STATIC(BFDD, BFDD_DPLANE_CTX, "Data plane client allocated memory"); /** Data plane client socket buffer size. */ #define BFD_DPLANE_CLIENT_BUF_SIZE 8192 struct bfd_dplane_ctx { /** Client file descriptor. */ int sock; /** Is this a connected or accepted? */ bool client; /** Is the socket still connecting? */ bool connecting; /** Client/server address. */ union { struct sockaddr sa; struct sockaddr_in sin; struct sockaddr_in6 sin6; struct sockaddr_un sun; } addr; /** Address length. */ socklen_t addrlen; /** Data plane current last used ID. */ uint16_t last_id; /** Input buffer data. */ struct stream *inbuf; /** Output buffer data. */ struct stream *outbuf; /** Input event data. */ struct event *inbufev; /** Output event data. */ struct event *outbufev; /** Connection event. */ struct event *connectev; /** Amount of bytes read. */ uint64_t in_bytes; /** Amount of bytes read peak. */ uint64_t in_bytes_peak; /** Amount of bytes written. */ uint64_t out_bytes; /** Amount of bytes written peak. */ uint64_t out_bytes_peak; /** Amount of output buffer full events (`bfd_dplane_enqueue` failed). */ uint64_t out_fullev; /** Amount of messages read (full messages). */ uint64_t in_msgs; /** Amount of messages enqueued (maybe written). */ uint64_t out_msgs; TAILQ_ENTRY(bfd_dplane_ctx) entry; }; /** * Callback type for `bfd_dplane_expect`. \see bfd_dplane_expect. */ typedef void (*bfd_dplane_expect_cb)(struct bfddp_message *msg, void *arg); static void bfd_dplane_client_connect(struct event *t); static bool bfd_dplane_client_connecting(struct bfd_dplane_ctx *bdc); static void bfd_dplane_ctx_free(struct bfd_dplane_ctx *bdc); static int _bfd_dplane_add_session(struct bfd_dplane_ctx *bdc, struct bfd_session *bs); /* * BFD data plane helper functions. */ static const char *bfd_dplane_messagetype2str(enum bfddp_message_type bmt) { switch (bmt) { case ECHO_REQUEST: return "ECHO_REQUEST"; case ECHO_REPLY: return "ECHO_REPLY"; case DP_ADD_SESSION: return "DP_ADD_SESSION"; case DP_DELETE_SESSION: return "DP_DELETE_SESSION"; case BFD_STATE_CHANGE: return "BFD_STATE_CHANGE"; case DP_REQUEST_SESSION_COUNTERS: return "DP_REQUEST_SESSION_COUNTERS"; case BFD_SESSION_COUNTERS: return "BFD_SESSION_COUNTERS"; default: return "UNKNOWN"; } } static void bfd_dplane_debug_message(const struct bfddp_message *msg) { enum bfddp_message_type bmt; char buf[256], addrs[256]; uint32_t flags; int rv; if (!bglobal.debug_dplane) return; bmt = ntohs(msg->header.type); zlog_debug("dplane-packet: [version=%d length=%d type=%s (%d)]", msg->header.version, ntohs(msg->header.length), bfd_dplane_messagetype2str(bmt), bmt); switch (bmt) { case ECHO_REPLY: case ECHO_REQUEST: zlog_debug(" [dp_time=%" PRIu64 " bfdd_time=%" PRIu64 "]", be64toh(msg->data.echo.dp_time), be64toh(msg->data.echo.bfdd_time)); break; case DP_ADD_SESSION: case DP_DELETE_SESSION: flags = ntohl(msg->data.session.flags); if (flags & SESSION_IPV6) snprintfrr(addrs, sizeof(addrs), "src=%pI6 dst=%pI6", &msg->data.session.src, &msg->data.session.dst); else snprintfrr(addrs, sizeof(addrs), "src=%pI4 dst=%pI4", (struct in_addr *)&msg->data.session.src, (struct in_addr *)&msg->data.session.dst); buf[0] = 0; if (flags & SESSION_CBIT) strlcat(buf, "cpi ", sizeof(buf)); if (flags & SESSION_ECHO) strlcat(buf, "echo ", sizeof(buf)); if (flags & SESSION_IPV6) strlcat(buf, "ipv6 ", sizeof(buf)); if (flags & SESSION_DEMAND) strlcat(buf, "demand ", sizeof(buf)); if (flags & SESSION_PASSIVE) strlcat(buf, "passive ", sizeof(buf)); if (flags & SESSION_MULTIHOP) strlcat(buf, "multihop ", sizeof(buf)); if (flags & SESSION_SHUTDOWN) strlcat(buf, "shutdown ", sizeof(buf)); /* Remove the last space to make things prettier. */ rv = (int)strlen(buf); if (rv > 0) buf[rv - 1] = 0; zlog_debug( " [flags=0x%08x{%s} %s ttl=%d detect_mult=%d " "ifindex=%d ifname=%s]", flags, buf, addrs, msg->data.session.ttl, msg->data.session.detect_mult, ntohl(msg->data.session.ifindex), msg->data.session.ifname); break; case BFD_STATE_CHANGE: buf[0] = 0; flags = ntohl(msg->data.state.remote_flags); if (flags & RBIT_CPI) strlcat(buf, "cbit ", sizeof(buf)); if (flags & RBIT_DEMAND) strlcat(buf, "demand ", sizeof(buf)); if (flags & RBIT_MP) strlcat(buf, "mp ", sizeof(buf)); /* Remove the last space to make things prettier. */ rv = (int)strlen(buf); if (rv > 0) buf[rv - 1] = 0; zlog_debug( " [lid=%u rid=%u flags=0x%02x{%s} state=%s " "diagnostics=%s mult=%d tx=%u rx=%u erx=%u]", ntohl(msg->data.state.lid), ntohl(msg->data.state.rid), flags, buf, state_list[msg->data.state.state].str, diag2str(msg->data.state.diagnostics), msg->data.state.detection_multiplier, ntohl(msg->data.state.desired_tx), ntohl(msg->data.state.required_rx), ntohl(msg->data.state.required_echo_rx)); break; case DP_REQUEST_SESSION_COUNTERS: zlog_debug(" [lid=%u]", ntohl(msg->data.counters_req.lid)); break; case BFD_SESSION_COUNTERS: zlog_debug( " [lid=%u " "control{in %" PRIu64 " bytes (%" PRIu64 " packets), " "out %" PRIu64 " bytes (%" PRIu64 " packets)} " "echo{in %" PRIu64 " bytes (%" PRIu64 " packets), " "out %" PRIu64 " bytes (%" PRIu64 " packets)}]", ntohl(msg->data.session_counters.lid), be64toh(msg->data.session_counters.control_input_bytes), be64toh(msg->data.session_counters .control_input_packets), be64toh(msg->data.session_counters .control_output_bytes), be64toh(msg->data.session_counters .control_output_packets), be64toh(msg->data.session_counters.echo_input_bytes), be64toh(msg->data.session_counters.echo_input_packets), be64toh(msg->data.session_counters.echo_output_bytes), be64toh(msg->data.session_counters .echo_output_packets)); break; } } /** * Gets the next unused non zero identification. * * \param bdc the data plane context. * * \returns next usable id. */ static uint16_t bfd_dplane_next_id(struct bfd_dplane_ctx *bdc) { bdc->last_id++; /* Don't use reserved id `0`. */ if (bdc->last_id == 0) bdc->last_id = 1; return bdc->last_id; } static ssize_t bfd_dplane_flush(struct bfd_dplane_ctx *bdc) { ssize_t total = 0; int rv; while (STREAM_READABLE(bdc->outbuf)) { /* Flush buffer contents to socket. */ rv = stream_flush(bdc->outbuf, bdc->sock); if (rv == -1) { /* Interruption: try again. */ if (errno == EAGAIN || errno == EWOULDBLOCK || errno == EINTR) continue; zlog_warn("%s: socket failed: %s", __func__, strerror(errno)); bfd_dplane_ctx_free(bdc); return 0; } if (rv == 0) { if (bglobal.debug_dplane) zlog_info("%s: connection closed", __func__); bfd_dplane_ctx_free(bdc); return 0; } /* Account total written. */ total += rv; /* Account output bytes. */ bdc->out_bytes += (uint64_t)rv; /* Forward pointer. */ stream_forward_getp(bdc->outbuf, (size_t)rv); } /* Make more space for new data. */ stream_pulldown(bdc->outbuf); /* Disable write ready events. */ EVENT_OFF(bdc->outbufev); return total; } static void bfd_dplane_write(struct event *t) { struct bfd_dplane_ctx *bdc = EVENT_ARG(t); /* Handle connection stage. */ if (bdc->connecting && bfd_dplane_client_connecting(bdc)) return; bfd_dplane_flush(bdc); } static void bfd_dplane_session_state_change(struct bfd_dplane_ctx *bdc, const struct bfddp_state_change *state) { struct bfd_session *bs; uint32_t flags; int old_state; /* Look up session. */ bs = bfd_id_lookup(ntohl(state->lid)); if (bs == NULL) { if (bglobal.debug_dplane) zlog_debug("%s: failed to find session to update", __func__); return; } flags = ntohl(state->remote_flags); old_state = bs->ses_state; /* Update session state. */ bs->ses_state = state->state; bs->remote_diag = state->diagnostics; bs->discrs.remote_discr = ntohl(state->rid); bs->remote_cbit = !!(flags & RBIT_CPI); bs->remote_detect_mult = state->detection_multiplier; bs->remote_timers.desired_min_tx = ntohl(state->desired_tx); bs->remote_timers.required_min_rx = ntohl(state->required_rx); bs->remote_timers.required_min_echo = ntohl(state->required_echo_rx); /* Notify and update counters. */ ptm_bfd_notify(bs, bs->ses_state); /* No state change. */ if (old_state == bs->ses_state) return; switch (bs->ses_state) { case PTM_BFD_ADM_DOWN: case PTM_BFD_DOWN: /* Both states mean down. */ if (old_state == PTM_BFD_ADM_DOWN || old_state == PTM_BFD_DOWN) break; monotime(&bs->downtime); bs->stats.session_down++; break; case PTM_BFD_UP: monotime(&bs->uptime); bs->stats.session_up++; break; case PTM_BFD_INIT: /* NOTHING */ break; default: zlog_warn("%s: unhandled new state %d", __func__, bs->ses_state); break; } if (bglobal.debug_peer_event) zlog_debug("state-change: [data plane: %s] %s -> %s", bs_to_string(bs), state_list[old_state].str, state_list[bs->ses_state].str); } /** * Enqueue message in output buffer. * * \param[in,out] bdc data plane client context. * \param[in] buf the message to buffer. * \param[in] buflen the amount of bytes to buffer. * * \returns `-1` on failure (buffer full) or `0` on success. */ static int bfd_dplane_enqueue(struct bfd_dplane_ctx *bdc, const void *buf, size_t buflen) { size_t rlen; /* Handle not connected yet client. */ if (bdc->client && bdc->sock == -1) return -1; /* Not enough space. */ if (buflen > STREAM_WRITEABLE(bdc->outbuf)) { bdc->out_fullev++; return -1; } /* Show debug message if active. */ bfd_dplane_debug_message((struct bfddp_message *)buf); /* Buffer the message. */ stream_write(bdc->outbuf, buf, buflen); /* Account message as sent. */ bdc->out_msgs++; /* Register peak buffered bytes. */ rlen = STREAM_READABLE(bdc->outbuf); if (bdc->out_bytes_peak < rlen) bdc->out_bytes_peak = rlen; /* Schedule if it is not yet. */ if (bdc->outbufev == NULL) event_add_write(master, bfd_dplane_write, bdc, bdc->sock, &bdc->outbufev); return 0; } static void bfd_dplane_echo_request_handle(struct bfd_dplane_ctx *bdc, const struct bfddp_message *bm) { struct bfddp_message msg = {}; uint16_t msglen = sizeof(msg.header) + sizeof(msg.data.echo); struct timeval tv; gettimeofday(&tv, NULL); /* Prepare header. */ msg.header.version = BFD_DP_VERSION; msg.header.type = htons(ECHO_REPLY); msg.header.length = htons(msglen); /* Prepare payload. */ msg.data.echo.dp_time = bm->data.echo.dp_time; msg.data.echo.bfdd_time = htobe64((uint64_t)((tv.tv_sec * 1000000) + tv.tv_usec)); /* Enqueue for output. */ bfd_dplane_enqueue(bdc, &msg, msglen); } static void bfd_dplane_handle_message(struct bfddp_message *msg, void *arg) { enum bfddp_message_type bmt; struct bfd_dplane_ctx *bdc = arg; /* Call the appropriated handler. */ bmt = ntohs(msg->header.type); switch (bmt) { case ECHO_REQUEST: bfd_dplane_echo_request_handle(bdc, msg); break; case BFD_STATE_CHANGE: bfd_dplane_session_state_change(bdc, &msg->data.state); break; case ECHO_REPLY: /* NOTHING: we don't do anything with this information. */ break; case DP_ADD_SESSION: case DP_DELETE_SESSION: case DP_REQUEST_SESSION_COUNTERS: /* NOTHING: we are not supposed to receive this. */ break; case BFD_SESSION_COUNTERS: /* * NOTHING: caller of DP_REQUEST_SESSION_COUNTERS should * handle this with `bfd_dplane_expect`. */ break; default: zlog_debug("%s: unhandled message type %d", __func__, bmt); break; } } /** * Reads the socket immediately to receive data plane answer to query. * * \param bdc the data plane context. * \param id the message ID waiting response. * \param cb the callback to call when ready. * \param arg the callback argument. * * \return * `-2` on unavailability (try again), `-1` on failure or `0` on success. */ static int bfd_dplane_expect(struct bfd_dplane_ctx *bdc, uint16_t id, bfd_dplane_expect_cb cb, void *arg) { struct bfddp_message_header *bh; size_t rlen = 0, reads = 0; ssize_t rv; /* * Don't attempt to read if buffer is full, otherwise we'll get a * bogus 'connection closed' signal (rv == 0). */ if (bdc->inbuf->endp == bdc->inbuf->size) goto skip_read; read_again: /* Attempt to read message from client. */ rv = stream_read_try(bdc->inbuf, bdc->sock, STREAM_WRITEABLE(bdc->inbuf)); if (rv == 0) { if (bglobal.debug_dplane) zlog_info("%s: socket closed", __func__); bfd_dplane_ctx_free(bdc); return -1; } if (rv == -1) { zlog_warn("%s: socket failed: %s", __func__, strerror(errno)); bfd_dplane_ctx_free(bdc); return -1; } /* We got interrupted, reschedule read. */ if (rv == -2) return -2; /* Account read bytes. */ bdc->in_bytes += (uint64_t)rv; /* Register peak buffered bytes. */ rlen = STREAM_READABLE(bdc->inbuf); if (bdc->in_bytes_peak < rlen) bdc->in_bytes_peak = rlen; skip_read: while (rlen > 0) { bh = (struct bfddp_message_header *)stream_pnt(bdc->inbuf); /* Not enough data read. */ if (ntohs(bh->length) > rlen) goto read_again; /* Account full message read. */ bdc->in_msgs++; /* Account this message as whole read for buffer reorganize. */ reads++; /* Check for bad version. */ if (bh->version != BFD_DP_VERSION) { zlog_err("%s: bad data plane client version: %d", __func__, bh->version); return -1; } /* Show debug message if active. */ bfd_dplane_debug_message((struct bfddp_message *)bh); /* * Handle incoming message with callback if the ID matches, * otherwise fallback to default handler. */ if (id && ntohs(bh->id) == id) cb((struct bfddp_message *)bh, arg); else bfd_dplane_handle_message((struct bfddp_message *)bh, bdc); /* Advance current read pointer. */ stream_forward_getp(bdc->inbuf, ntohs(bh->length)); /* Reduce the buffer available bytes. */ rlen -= ntohs(bh->length); /* Reorganize buffer to handle more bytes read. */ if (reads >= 3) { stream_pulldown(bdc->inbuf); reads = 0; } /* We found the message, return to caller. */ if (id && ntohs(bh->id) == id) break; } return 0; } static void bfd_dplane_read(struct event *t) { struct bfd_dplane_ctx *bdc = EVENT_ARG(t); int rv; rv = bfd_dplane_expect(bdc, 0, bfd_dplane_handle_message, NULL); if (rv == -1) return; stream_pulldown(bdc->inbuf); event_add_read(master, bfd_dplane_read, bdc, bdc->sock, &bdc->inbufev); } static void _bfd_session_register_dplane(struct hash_bucket *hb, void *arg) { struct bfd_session *bs = hb->data; struct bfd_dplane_ctx *bdc = arg; if (bs->bdc != NULL) return; /* Disable software session. */ bfd_session_disable(bs); /* Move session to data plane. */ _bfd_dplane_add_session(bdc, bs); } static struct bfd_dplane_ctx *bfd_dplane_ctx_new(int sock) { struct bfd_dplane_ctx *bdc; bdc = XCALLOC(MTYPE_BFDD_DPLANE_CTX, sizeof(*bdc)); bdc->sock = sock; bdc->inbuf = stream_new(BFD_DPLANE_CLIENT_BUF_SIZE); bdc->outbuf = stream_new(BFD_DPLANE_CLIENT_BUF_SIZE); /* If not socket ready, skip read and session registration. */ if (sock == -1) return bdc; event_add_read(master, bfd_dplane_read, bdc, sock, &bdc->inbufev); /* Register all unattached sessions. */ bfd_key_iterate(_bfd_session_register_dplane, bdc); return bdc; } static void _bfd_session_unregister_dplane(struct hash_bucket *hb, void *arg) { struct bfd_session *bs = hb->data; struct bfd_dplane_ctx *bdc = arg; if (bs->bdc != bdc) return; bs->bdc = NULL; /* Fallback to software. */ bfd_session_enable(bs); } static void bfd_dplane_ctx_free(struct bfd_dplane_ctx *bdc) { if (bglobal.debug_dplane) zlog_debug("%s: terminating data plane client %d", __func__, bdc->sock); /* Client mode has special treatment. */ if (bdc->client) { /* Disable connection event if any. */ EVENT_OFF(bdc->connectev); /* Normal treatment on shutdown. */ if (bglobal.bg_shutdown) goto free_resources; /* Attempt reconnection. */ socket_close(&bdc->sock); EVENT_OFF(bdc->inbufev); EVENT_OFF(bdc->outbufev); event_add_timer(master, bfd_dplane_client_connect, bdc, 3, &bdc->connectev); return; } free_resources: /* Remove from the list of attached data planes. */ TAILQ_REMOVE(&bglobal.bg_dplaneq, bdc, entry); /* Detach all associated sessions. */ if (bglobal.bg_shutdown == false) bfd_key_iterate(_bfd_session_unregister_dplane, bdc); /* Free resources. */ socket_close(&bdc->sock); stream_free(bdc->inbuf); stream_free(bdc->outbuf); EVENT_OFF(bdc->inbufev); EVENT_OFF(bdc->outbufev); XFREE(MTYPE_BFDD_DPLANE_CTX, bdc); } static void _bfd_dplane_session_fill(const struct bfd_session *bs, struct bfddp_message *msg) { uint16_t msglen = sizeof(msg->header) + sizeof(msg->data.session); /* Message header. */ msg->header.version = BFD_DP_VERSION; msg->header.length = ntohs(msglen); msg->header.type = ntohs(DP_ADD_SESSION); /* Message payload. */ msg->data.session.dst = bs->key.peer; msg->data.session.src = bs->key.local; msg->data.session.detect_mult = bs->detect_mult; if (bs->ifp) { msg->data.session.ifindex = htonl(bs->ifp->ifindex); strlcpy(msg->data.session.ifname, bs->ifp->name, sizeof(msg->data.session.ifname)); } if (bs->flags & BFD_SESS_FLAG_MH) { msg->data.session.flags |= SESSION_MULTIHOP; msg->data.session.ttl = bs->mh_ttl; } else msg->data.session.ttl = BFD_TTL_VAL; if (bs->flags & BFD_SESS_FLAG_IPV6) msg->data.session.flags |= SESSION_IPV6; if (bs->flags & BFD_SESS_FLAG_ECHO) msg->data.session.flags |= SESSION_ECHO; if (bs->flags & BFD_SESS_FLAG_CBIT) msg->data.session.flags |= SESSION_CBIT; if (bs->flags & BFD_SESS_FLAG_PASSIVE) msg->data.session.flags |= SESSION_PASSIVE; if (bs->flags & BFD_SESS_FLAG_SHUTDOWN) msg->data.session.flags |= SESSION_SHUTDOWN; msg->data.session.flags = htonl(msg->data.session.flags); msg->data.session.lid = htonl(bs->discrs.my_discr); msg->data.session.min_tx = htonl(bs->timers.desired_min_tx); msg->data.session.min_rx = htonl(bs->timers.required_min_rx); msg->data.session.min_echo_tx = htonl(bs->timers.desired_min_echo_tx); msg->data.session.min_echo_rx = htonl(bs->timers.required_min_echo_rx); } static int _bfd_dplane_add_session(struct bfd_dplane_ctx *bdc, struct bfd_session *bs) { int rv; /* Associate session. */ bs->bdc = bdc; /* Reset previous state. */ bs->remote_diag = 0; bs->local_diag = 0; bs->ses_state = PTM_BFD_DOWN; /* Enqueue message to data plane client. */ rv = bfd_dplane_update_session(bs); if (rv != 0) bs->bdc = NULL; return rv; } static void _bfd_dplane_update_session_counters(struct bfddp_message *msg, void *arg) { struct bfd_session *bs = arg; bs->stats.rx_ctrl_pkt = be64toh(msg->data.session_counters.control_input_packets); bs->stats.tx_ctrl_pkt = be64toh(msg->data.session_counters.control_output_packets); bs->stats.rx_echo_pkt = be64toh(msg->data.session_counters.echo_input_packets); bs->stats.tx_echo_pkt = be64toh(msg->data.session_counters.echo_output_bytes); } /** * Send message to data plane requesting the session counters. * * \param bs the BFD session. * * \returns `0` on failure or the request id. */ static uint16_t bfd_dplane_request_counters(const struct bfd_session *bs) { struct bfddp_message msg = {}; size_t msglen = sizeof(msg.header) + sizeof(msg.data.counters_req); /* Fill header information. */ msg.header.version = BFD_DP_VERSION; msg.header.length = htons(msglen); msg.header.type = htons(DP_REQUEST_SESSION_COUNTERS); msg.header.id = htons(bfd_dplane_next_id(bs->bdc)); /* Session to get counters. */ msg.data.counters_req.lid = htonl(bs->discrs.my_discr); /* If enqueue failed, let caller know. */ if (bfd_dplane_enqueue(bs->bdc, &msg, msglen) == -1) return 0; /* Flush socket. */ bfd_dplane_flush(bs->bdc); return ntohs(msg.header.id); } /* * Data plane listening socket. */ static void bfd_dplane_accept(struct event *t) { struct bfd_global *bg = EVENT_ARG(t); struct bfd_dplane_ctx *bdc; int sock; /* Accept new connection. */ sock = accept(bg->bg_dplane_sock, NULL, 0); if (sock == -1) { zlog_warn("%s: accept failed: %s", __func__, strerror(errno)); goto reschedule_and_return; } /* Create and handle new connection. */ bdc = bfd_dplane_ctx_new(sock); TAILQ_INSERT_TAIL(&bglobal.bg_dplaneq, bdc, entry); if (bglobal.debug_dplane) zlog_debug("%s: new data plane client connected", __func__); reschedule_and_return: event_add_read(master, bfd_dplane_accept, bg, bg->bg_dplane_sock, &bglobal.bg_dplane_sockev); } /* * Data plane connecting socket. */ static void _bfd_dplane_client_bootstrap(struct bfd_dplane_ctx *bdc) { bdc->connecting = false; /* Clean up buffers. */ stream_reset(bdc->inbuf); stream_reset(bdc->outbuf); /* Ask for read notifications. */ event_add_read(master, bfd_dplane_read, bdc, bdc->sock, &bdc->inbufev); /* Remove all sessions then register again to send them all. */ bfd_key_iterate(_bfd_session_unregister_dplane, bdc); bfd_key_iterate(_bfd_session_register_dplane, bdc); } static bool bfd_dplane_client_connecting(struct bfd_dplane_ctx *bdc) { int rv; socklen_t rvlen = sizeof(rv); /* Make sure `errno` is reset, then test `getsockopt` success. */ errno = 0; if (getsockopt(bdc->sock, SOL_SOCKET, SO_ERROR, &rv, &rvlen) == -1) rv = -1; /* Connection successful. */ if (rv == 0) { if (bglobal.debug_dplane) zlog_debug("%s: connected to server: %d", __func__, bdc->sock); _bfd_dplane_client_bootstrap(bdc); return false; } switch (rv) { case EINTR: case EAGAIN: case EALREADY: case EINPROGRESS: /* non error, wait more. */ return true; default: zlog_warn("%s: connection failed: %s", __func__, strerror(errno)); bfd_dplane_ctx_free(bdc); return true; } } static void bfd_dplane_client_connect(struct event *t) { struct bfd_dplane_ctx *bdc = EVENT_ARG(t); int rv, sock; socklen_t rvlen = sizeof(rv); /* Allocate new socket. */ sock = socket(bdc->addr.sa.sa_family, SOCK_STREAM, 0); if (sock == -1) { zlog_warn("%s: failed to initialize socket: %s", __func__, strerror(errno)); goto reschedule_connect; } /* Set non blocking socket. */ set_nonblocking(sock); /* Set 'no delay' (disables nagle algorithm) for IPv4/IPv6. */ rv = 1; if (bdc->addr.sa.sa_family != AF_UNIX && setsockopt(sock, IPPROTO_TCP, TCP_NODELAY, &rv, rvlen) == -1) zlog_warn("%s: TCP_NODELAY: %s", __func__, strerror(errno)); /* Attempt to connect. */ rv = connect(sock, &bdc->addr.sa, bdc->addrlen); if (rv == -1 && (errno != EINPROGRESS && errno != EAGAIN)) { zlog_warn("%s: data plane connection failed: %s", __func__, strerror(errno)); goto reschedule_connect; } bdc->sock = sock; if (rv == -1) { if (bglobal.debug_dplane) zlog_debug("%s: server connection in progress: %d", __func__, sock); /* If we are not connected yet, ask for write notifications. */ bdc->connecting = true; event_add_write(master, bfd_dplane_write, bdc, bdc->sock, &bdc->outbufev); } else { if (bglobal.debug_dplane) zlog_debug("%s: server connection: %d", __func__, sock); /* Otherwise just start accepting data. */ _bfd_dplane_client_bootstrap(bdc); } reschedule_connect: EVENT_OFF(bdc->inbufev); EVENT_OFF(bdc->outbufev); socket_close(&sock); event_add_timer(master, bfd_dplane_client_connect, bdc, 3, &bdc->connectev); } static void bfd_dplane_client_init(const struct sockaddr *sa, socklen_t salen) { struct bfd_dplane_ctx *bdc; /* Allocate context and copy address for reconnection. */ bdc = bfd_dplane_ctx_new(-1); if (salen <= sizeof(bdc->addr)) { memcpy(&bdc->addr, sa, salen); bdc->addrlen = sizeof(bdc->addr); } else { memcpy(&bdc->addr, sa, sizeof(bdc->addr)); bdc->addrlen = sizeof(bdc->addr); zlog_warn("%s: server address truncated (from %d to %d)", __func__, salen, bdc->addrlen); } bdc->client = true; event_add_timer(master, bfd_dplane_client_connect, bdc, 0, &bdc->connectev); /* Insert into data plane lists. */ TAILQ_INSERT_TAIL(&bglobal.bg_dplaneq, bdc, entry); } /** * Termination phase of the distributed BFD infrastructure: free all allocated * resources. */ static int bfd_dplane_finish_late(void) { struct bfd_dplane_ctx *bdc; if (bglobal.debug_dplane) zlog_debug("%s: terminating distributed BFD", __func__); /* Free all data plane client contexts. */ while ((bdc = TAILQ_FIRST(&bglobal.bg_dplaneq)) != NULL) bfd_dplane_ctx_free(bdc); /* Cancel accept thread and close socket. */ EVENT_OFF(bglobal.bg_dplane_sockev); close(bglobal.bg_dplane_sock); return 0; } /* * Data plane exported functions. */ void bfd_dplane_init(const struct sockaddr *sa, socklen_t salen, bool client) { int sock; zlog_info("initializing distributed BFD"); /* Initialize queue header. */ TAILQ_INIT(&bglobal.bg_dplaneq); /* Initialize listening socket. */ bglobal.bg_dplane_sock = -1; /* Observe shutdown events. */ hook_register(frr_fini, bfd_dplane_finish_late); /* Handle client mode. */ if (client) { bfd_dplane_client_init(sa, salen); return; } /* * Data plane socket creation: * - Set REUSEADDR option for taking over previously open socket. * - Bind to address requested (maybe IPv4, IPv6, UNIX etc...). * - Listen on that address for new connections. * - Ask to be waken up when a new connection comes. */ sock = socket(sa->sa_family, SOCK_STREAM, 0); if (sock == -1) { zlog_warn("%s: failed to initialize socket: %s", __func__, strerror(errno)); return; } if (sockopt_reuseaddr(sock) == -1) { zlog_warn("%s: failed to set reuseaddr: %s", __func__, strerror(errno)); close(sock); return; } /* Handle UNIX socket: delete previous socket if any. */ if (sa->sa_family == AF_UNIX) unlink(((struct sockaddr_un *)sa)->sun_path); if (bind(sock, sa, salen) == -1) { zlog_warn("%s: failed to bind socket: %s", __func__, strerror(errno)); close(sock); return; } if (listen(sock, SOMAXCONN) == -1) { zlog_warn("%s: failed to put socket on listen: %s", __func__, strerror(errno)); close(sock); return; } bglobal.bg_dplane_sock = sock; event_add_read(master, bfd_dplane_accept, &bglobal, sock, &bglobal.bg_dplane_sockev); } int bfd_dplane_add_session(struct bfd_session *bs) { struct bfd_dplane_ctx *bdc; /* Select a data plane client to install session. */ TAILQ_FOREACH (bdc, &bglobal.bg_dplaneq, entry) { if (_bfd_dplane_add_session(bdc, bs) == 0) return 0; } return -1; } int bfd_dplane_update_session(const struct bfd_session *bs) { struct bfddp_message msg = {}; if (bs->bdc == NULL) return 0; _bfd_dplane_session_fill(bs, &msg); /* Enqueue message to data plane client. */ return bfd_dplane_enqueue(bs->bdc, &msg, ntohs(msg.header.length)); } int bfd_dplane_delete_session(struct bfd_session *bs) { struct bfddp_message msg = {}; int rv; /* Not using data plane, just return success. */ if (bs->bdc == NULL) return 0; /* Fill most of the common fields. */ _bfd_dplane_session_fill(bs, &msg); /* Change the message type. */ msg.header.type = ntohs(DP_DELETE_SESSION); /* Enqueue message to data plane client. */ rv = bfd_dplane_enqueue(bs->bdc, &msg, ntohs(msg.header.length)); /* Remove association. */ bs->bdc = NULL; return rv; } /* * Data plane CLI. */ void bfd_dplane_show_counters(struct vty *vty) { struct bfd_dplane_ctx *bdc; #define SHOW_COUNTER(label, counter, formatter) \ vty_out(vty, "%28s: %" formatter "\n", (label), (counter)) vty_out(vty, "%28s\n%28s\n", "Data plane", "=========="); TAILQ_FOREACH (bdc, &bglobal.bg_dplaneq, entry) { SHOW_COUNTER("File descriptor", bdc->sock, "d"); SHOW_COUNTER("Input bytes", bdc->in_bytes, PRIu64); SHOW_COUNTER("Input bytes peak", bdc->in_bytes_peak, PRIu64); SHOW_COUNTER("Input messages", bdc->in_msgs, PRIu64); SHOW_COUNTER("Input current usage", STREAM_READABLE(bdc->inbuf), "zu"); SHOW_COUNTER("Output bytes", bdc->out_bytes, PRIu64); SHOW_COUNTER("Output bytes peak", bdc->out_bytes_peak, PRIu64); SHOW_COUNTER("Output messages", bdc->out_msgs, PRIu64); SHOW_COUNTER("Output full events", bdc->out_fullev, PRIu64); SHOW_COUNTER("Output current usage", STREAM_READABLE(bdc->inbuf), "zu"); vty_out(vty, "\n"); } #undef SHOW_COUNTER } int bfd_dplane_update_session_counters(struct bfd_session *bs) { uint16_t id; int rv; /* If session is not using data plane, then just return success. */ if (bs->bdc == NULL) return 0; /* Make the request. */ id = bfd_dplane_request_counters(bs); if (id == 0) { zlog_debug("%s: counters request failed", __func__); return -1; } /* Handle interruptions. */ do { rv = bfd_dplane_expect(bs->bdc, id, _bfd_dplane_update_session_counters, bs); } while (rv == -2); return rv; }