/* * (C) 2012-2013 by Pablo Neira Ayuso * (C) 2012-2013 by On Waves ehf * All rights not specifically granted under this license are reserved. * * This program is free software; you can redistribute it and/or modify it * under the terms of the GNU Affero General Public License as published by the * Free Software Foundation; either version 3 of the License, or (at your * option) any later version. */ #include /* for printf */ #include /* for memcpy */ #include /* for abs */ #include /* for PRIu64 */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include static struct osmo_fd osmux_fd_v4; static struct osmo_fd osmux_fd_v6; static LLIST_HEAD(osmux_handle_list); struct osmux_handle { struct llist_head head; struct osmux_in_handle *in; struct osmo_sockaddr rem_addr; int refcnt; }; const struct value_string osmux_state_strs[] = { { OSMUX_STATE_DISABLED, "disabled" }, { OSMUX_STATE_ACTIVATING, "activating" }, { OSMUX_STATE_ENABLED, "enabled" }, { 0, NULL } }; static const struct rate_ctr_group_desc rate_ctr_group_osmux_desc = { .group_name_prefix = "conn_osmux", .group_description = "Osmux connection statistics", .class_id = 1, .num_ctr = ARRAY_SIZE(mgcp_conn_osmux_rate_ctr_desc), .ctr_desc = mgcp_conn_osmux_rate_ctr_desc }; static void rtpconn_osmux_rate_ctr_add(struct mgcp_conn_rtp *conn_rtp, int id, int inc) { struct rate_ctr_group *conn_osmux_stats = conn_rtp->osmux.ctrg; struct rate_ctr_group *trunk_osmux_stats = conn_rtp->conn->endp->trunk->ratectr.all_osmux_conn_stats; /* add to both the per-connection and the global stats */ rate_ctr_add(rate_ctr_group_get_ctr(conn_osmux_stats, id), inc); rate_ctr_add(rate_ctr_group_get_ctr(trunk_osmux_stats, id), inc); } static void rtpconn_osmux_rate_ctr_inc(struct mgcp_conn_rtp *conn_rtp, int id) { rtpconn_osmux_rate_ctr_add(conn_rtp, id, 1); } /* Deliver OSMUX batch to the remote end */ static void osmux_deliver_cb(struct msgb *batch_msg, void *data) { struct osmux_handle *handle = data; socklen_t dest_len; int rc, fd; struct mgcp_trunk *trunk = (struct mgcp_trunk *)osmux_fd_v4.data; struct rate_ctr_group *all_osmux_stats = trunk->ratectr.all_osmux_conn_stats; switch (handle->rem_addr.u.sa.sa_family) { case AF_INET6: dest_len = sizeof(handle->rem_addr.u.sin6); fd = osmux_fd_v6.fd; break; case AF_INET: default: dest_len = sizeof(handle->rem_addr.u.sin); fd = osmux_fd_v4.fd; break; } rc = sendto(fd, batch_msg->data, batch_msg->len, 0, (struct sockaddr *)&handle->rem_addr.u.sa, dest_len); if (rc < 0) { char errbuf[129]; strerror_r(errno, errbuf, sizeof(errbuf)); LOGP(DOSMUX, LOGL_NOTICE, "osmux sendto(%s) failed: %s\n", osmo_sockaddr_to_str(&handle->rem_addr), errbuf); rate_ctr_inc(rate_ctr_group_get_ctr(all_osmux_stats, OSMUX_DROPPED_PACKETS_CTR)); } else { rate_ctr_inc(rate_ctr_group_get_ctr(all_osmux_stats, OSMUX_PACKETS_TX_CTR)); } msgb_free(batch_msg); } /* Lookup existing OSMUX handle for specified destination address. */ static struct osmux_handle * osmux_handle_find_get(const struct osmo_sockaddr *rem_addr) { struct osmux_handle *h; llist_for_each_entry(h, &osmux_handle_list, head) { if (osmo_sockaddr_cmp(&h->rem_addr, rem_addr) == 0) { h->refcnt++; LOGP(DOSMUX, LOGL_DEBUG, "Using existing OSMUX handle for addr=%s (rfcnt=%u)\n", osmo_sockaddr_to_str(rem_addr), h->refcnt); return h; } } return NULL; } /* Put down no longer needed OSMUX handle */ static void osmux_handle_put(struct osmux_in_handle *in) { struct osmux_handle *h; llist_for_each_entry(h, &osmux_handle_list, head) { if (h->in == in) { LOGP(DOSMUX, LOGL_DEBUG, "Putting existing OSMUX handle for addr=%s (rfcnt=%u)\n", osmo_sockaddr_to_str(&h->rem_addr), h->refcnt); if (--h->refcnt == 0) { LOGP(DOSMUX, LOGL_INFO, "Releasing unused osmux handle for %s\n", osmo_sockaddr_to_str(&h->rem_addr)); llist_del(&h->head); TALLOC_FREE(h->in); talloc_free(h); } return; } } LOGP(DOSMUX, LOGL_ERROR, "Cannot find Osmux input handle %p\n", in); } /* Allocate free OSMUX handle */ static struct osmux_handle * osmux_handle_alloc(const struct mgcp_trunk *trunk, const struct osmo_sockaddr *rem_addr) { struct osmux_handle *h; const struct mgcp_config *cfg = trunk->cfg; h = talloc_zero(trunk, struct osmux_handle); if (!h) return NULL; h->rem_addr = *rem_addr; h->refcnt++; h->in = osmux_xfrm_input_alloc(h); if (!h->in) { talloc_free(h); return NULL; } /* sequence number to start OSMUX message from */ osmux_xfrm_input_set_initial_seqnum(h->in, 0); osmux_xfrm_input_set_batch_factor(h->in, cfg->osmux.batch_factor); /* If batch size is zero, the library defaults to 1472 bytes. */ osmux_xfrm_input_set_batch_size(h->in, cfg->osmux.batch_size); osmux_xfrm_input_set_deliver_cb(h->in, osmux_deliver_cb, h); llist_add(&h->head, &osmux_handle_list); LOGP(DOSMUX, LOGL_DEBUG, "Created new OSMUX handle for rem_addr=%s\n", osmo_sockaddr_to_str(rem_addr)); return h; } /* Lookup existing handle for a specified address, if the handle can not be * found, the function will automatically allocate one */ static struct osmux_in_handle * osmux_handle_find_or_create(const struct mgcp_trunk *trunk, const struct osmo_sockaddr *rem_addr) { struct osmux_handle *h; h = osmux_handle_find_get(rem_addr); if (h != NULL) return h->in; h = osmux_handle_alloc(trunk, rem_addr); if (h == NULL) return NULL; return h->in; } /*! send RTP packet through OSMUX connection. * \param[in] conn associated RTP connection * \param[in] msg msgb containing an RTP AMR packet * \returns 0 on success, -1 on ERROR */ int conn_osmux_send_rtp(struct mgcp_conn_rtp *conn, struct msgb *msg) { int ret; struct msgb *msg2; if (!conn->end.output_enabled) { rtpconn_osmux_rate_ctr_inc(conn, OSMUX_RTP_PACKETS_TX_DROPPED_CTR); return -1; } if (conn->osmux.state != OSMUX_STATE_ENABLED) { LOGPCONN(conn->conn, DOSMUX, LOGL_INFO, "forwarding RTP to Osmux conn not yet enabled, dropping (cid=%d)\n", conn->osmux.remote_cid); rtpconn_osmux_rate_ctr_inc(conn, OSMUX_RTP_PACKETS_TX_DROPPED_CTR); return -1; } /* msg is not owned by us and will be freed by the caller stack upon return: */ msg2 = msgb_copy_c(conn->conn, msg, "osmux-rtp-send"); if (!msg2) return -1; while ((ret = osmux_xfrm_input(conn->osmux.in, msg2, conn->osmux.remote_cid)) > 0) { /* batch full, build and deliver it */ osmux_xfrm_input_deliver(conn->osmux.in); } if (ret < 0) { rtpconn_osmux_rate_ctr_inc(conn, OSMUX_RTP_PACKETS_TX_DROPPED_CTR); } else { rtpconn_osmux_rate_ctr_inc(conn, OSMUX_RTP_PACKETS_TX_CTR); rtpconn_osmux_rate_ctr_add(conn, OSMUX_AMR_OCTETS_TX_CTR, msgb_length(msg2) - sizeof(struct rtp_hdr)); } return 0; } /* Lookup the endpoint that corresponds to the specified address (port) */ static struct mgcp_conn_rtp* osmux_conn_lookup(const struct mgcp_trunk *trunk, uint8_t local_cid, const struct osmo_sockaddr *rem_addr) { struct mgcp_endpoint *endp; struct mgcp_conn *conn = NULL; struct mgcp_conn_rtp *conn_rtp; struct osmux_handle *h; int i; for (i = 0; i < trunk->number_endpoints; i++) { endp = trunk->endpoints[i]; llist_for_each_entry(conn, &endp->conns, entry) { if (conn->type != MGCP_CONN_TYPE_RTP) continue; conn_rtp = &conn->u.rtp; if (!mgcp_conn_rtp_is_osmux(conn_rtp)) continue; /* If Osmux peer is behind NAT: * + state OSMUX_STATE_ACTIVATING: we cannot validate the remote address & port for * the conn since we actually set conn's remote IP address from the info we received * from this source address. NOTE: This means if Osmux peer is behind NAT we cannot * have more than 1 osmux trunk since it's not possible to differentiate based on * remote address. * + state OSMUX_STATE_ENABLED: the conn is fully established (remote address is known), * it is now posssible to validate the remote address doesn't change. * If Osmux peer is not behind NAT: * We can always validate the remote IP address is matching the one we received in * CRCX/MDCX, we can support several parallel Osmux trunks since we can differentiate same CID * based on remote IP addr+port. However, if Osmux peer is not behind NAT it means it will go * into OSMUX_STATE_ENABLED as soon as the remote address is known, meaning if the conn is not * in that state we cannot (nor want) validate the IP address, we want to skip it until it is * ready (to avoid 3rd party data injections). * TLDR: When in OSMUX_STATE_ENABLED we can always validate remote address+port. * When in OSMUX_STATE_ACTIVATING, in case peer behind NAT we select it, * in case peer NOT behind NAT we skip it. */ if (conn_rtp->osmux.state == OSMUX_STATE_ENABLED) { h = osmux_xfrm_input_get_deliver_cb_data(conn_rtp->osmux.in); if (osmo_sockaddr_cmp(&h->rem_addr, rem_addr) != 0) continue; } else if (!trunk->cfg->osmux.peer_behind_nat) { LOGPCONN(conn, DOSMUX, LOGL_DEBUG, "osmux_conn_lookup(rem_addr=%s local_cid=%d): Skipping because not (yet) ENABLED\n", osmo_sockaddr_to_str(rem_addr), local_cid); continue; /* skip, read above */ } /* else: continue CID validation below: */ if (conn_rtp->osmux.local_cid == local_cid) return conn_rtp; } } LOGP(DOSMUX, LOGL_DEBUG, "Cannot find osmux conn with rem_addr=%s local_cid=%d\n", osmo_sockaddr_to_str(rem_addr), local_cid); return NULL; } static void scheduled_from_osmux_tx_rtp_cb(struct msgb *msg, void *data) { struct mgcp_conn_rtp *conn = data; const struct mgcp_endpoint *endp = conn->conn->endp; struct osmux_handle *h = osmux_xfrm_input_get_deliver_cb_data(conn->osmux.in); struct osmo_rtp_msg_ctx *mc = OSMO_RTP_MSG_CTX(msg); *mc = (struct osmo_rtp_msg_ctx){ .proto = MGCP_PROTO_RTP, .conn_src = conn, .from_addr = &h->rem_addr, }; endp->type->dispatch_rtp_cb(msg); msgb_free(msg); } static struct msgb *osmux_recv(struct osmo_fd *ofd, struct osmo_sockaddr *addr) { struct msgb *msg; socklen_t slen = sizeof(addr->u.sas); int ret; msg = msgb_alloc(4096, "OSMUX"); if (!msg) { LOGP(DOSMUX, LOGL_ERROR, "cannot allocate message\n"); return NULL; } ret = recvfrom(ofd->fd, msg->data, msg->data_len, 0, &addr->u.sa, &slen); if (ret <= 0) { msgb_free(msg); LOGP(DOSMUX, LOGL_ERROR, "cannot receive message\n"); return NULL; } msgb_put(msg, ret); return msg; } /* To be called every time some AMR data is received on a connection * returns: 0 if conn can process data, negative if an error ocurred and data should not be further processed */ static int conn_osmux_event_data_received(struct mgcp_conn_rtp *conn, const struct osmo_sockaddr *rem_addr) { const struct mgcp_config *cfg; switch(conn->osmux.state) { case OSMUX_STATE_ACTIVATING: /* If peer is not behind NAT, transition to OSMUX_STATE_ENABLED is done through * conn_osmux_rx_mdcx() whenever a CRCX/MDCX with the remote address is received. */ cfg = conn->conn->endp->trunk->cfg; if (!cfg->osmux.peer_behind_nat) { /* osmux_conn_lookup() should never provide us with an * ACTIVATING conn without NAT in first place. This should never happen. */ LOGPCONN(conn->conn, DOSMUX, LOGL_ERROR, "Unexpected rx osmux data for conn in ACTIVATING state without NAT\n"); return -1; } /* We have to wait until we received the remote CID from CRCX/MDCX. */ if (!conn->osmux.remote_cid_present) return -1; /* Update remote address with the src address of the package we received */ conn->end.addr = *rem_addr; /* mgcp_rtp_end_remote_addr_available() is now true and we can enable the conn: */ if (conn_osmux_enable(conn) < 0) { LOGPCONN(conn->conn, DOSMUX, LOGL_ERROR, "Could not enable osmux conn: %s\n", mgcp_conn_dump(conn->conn)); return -1; } return 0; case OSMUX_STATE_ENABLED: return 0; default: return -1; } } /* To be called every time an CRCX/MDCX is received. * returns: 0 if conn can continue, negative if an error ocurred during setup */ int conn_osmux_event_rx_crcx_mdcx(struct mgcp_conn_rtp *conn) { struct mgcp_config *cfg; switch (conn->osmux.state) { case OSMUX_STATE_ACTIVATING: /* If peer is behind NAT, we have to wait until 1st osmux frame is received * to discover peer's real remote address */ cfg = conn->conn->endp->trunk->cfg; if (cfg->osmux.peer_behind_nat) return 0; /* Keep waiting to receive remote CID through CRCX/MDCX */ if (!conn->osmux.remote_cid_present) return 0; /* keep waiting to receive remote address through CRCX/MDCX */ if (!mgcp_rtp_end_remote_addr_available(&conn->end)) return 0; /* Since the peer is not behind NAT, we can enable the conn right away since the proper * remote address is now known: */ if (conn_osmux_enable(conn) < 0) return -1; /* We have already transitioned to OSMUX_STATE_ENABLED here */ return 0; case OSMUX_STATE_ENABLED: return 0; default: OSMO_ASSERT(NULL); } return 0; } /* Old versions of osmux used to send dummy packets [0x23 0x] to punch the * hole in the NAT. Let's handle them speficially. */ static int osmux_handle_legacy_dummy(const struct mgcp_trunk *trunk, const struct osmo_sockaddr *rem_addr, struct msgb *msg) { uint8_t osmux_cid = msg->data[1]; struct mgcp_conn_rtp *conn; conn = osmux_conn_lookup(trunk, osmux_cid, rem_addr); if (!conn) { LOGP(DOSMUX, LOGL_DEBUG, "Cannot find conn for Osmux CID %d\n", osmux_cid); goto out; } conn_osmux_event_data_received(conn, rem_addr); /* Only needed to punch hole in firewall, it can be dropped */ out: msgb_free(msg); return 0; } #define osmux_chunk_length(msg, rem) ((rem) - (msg)->len) static int osmux_read_fd_cb(struct osmo_fd *ofd, unsigned int what) { struct msgb *msg; struct osmux_hdr *osmuxh; struct osmo_sockaddr rem_addr; uint32_t rem; struct mgcp_trunk *trunk = ofd->data; struct rate_ctr_group *all_rtp_stats = trunk->ratectr.all_osmux_conn_stats; char addr_str[64]; msg = osmux_recv(ofd, &rem_addr); if (!msg) return -1; rate_ctr_inc(rate_ctr_group_get_ctr(all_rtp_stats, OSMUX_PACKETS_RX_CTR)); osmo_sockaddr_to_str_buf(addr_str, sizeof(addr_str), &rem_addr); if (trunk->cfg->osmux.usage == OSMUX_USAGE_OFF) { LOGP(DOSMUX, LOGL_ERROR, "Peer %s wants to use Osmux but MGCP Client did not request it\n", addr_str); goto out; } /* Catch legacy dummy message and process them separately: */ if (msg->len == 2 && msg->data[0] == MGCP_DUMMY_LOAD) return osmux_handle_legacy_dummy(trunk, &rem_addr, msg); rem = msg->len; while((osmuxh = osmux_xfrm_output_pull(msg)) != NULL) { struct mgcp_conn_rtp *conn_src; conn_src = osmux_conn_lookup(trunk, osmuxh->circuit_id, &rem_addr); if (!conn_src) { LOGP(DOSMUX, LOGL_DEBUG, "Cannot find a src conn for %s CID=%d\n", addr_str, osmuxh->circuit_id); goto next; } if (conn_osmux_event_data_received(conn_src, &rem_addr) < 0) goto next; mgcp_conn_watchdog_kick(conn_src->conn); rtpconn_osmux_rate_ctr_inc(conn_src, OSMUX_CHUNKS_RX_CTR); rtpconn_osmux_rate_ctr_add(conn_src, OSMUX_OCTETS_RX_CTR, osmux_chunk_length(msg, rem)); osmux_xfrm_output_sched(conn_src->osmux.out, osmuxh); next: rem = msg->len; } out: msgb_free(msg); return 0; } int osmux_init(struct mgcp_trunk *trunk) { int ret; struct mgcp_config *cfg = trunk->cfg; /* So far we only support running on one trunk: */ OSMO_ASSERT(trunk == mgcp_trunk_by_num(cfg, MGCP_TRUNK_VIRTUAL, MGCP_VIRT_TRUNK_ID)); osmo_fd_setup(&osmux_fd_v4, -1, OSMO_FD_READ, osmux_read_fd_cb, trunk, 0); osmo_fd_setup(&osmux_fd_v6, -1, OSMO_FD_READ, osmux_read_fd_cb, trunk, 0); if (cfg->osmux.local_addr_v4) { ret = mgcp_create_bind(cfg->osmux.local_addr_v4, &osmux_fd_v4, cfg->osmux.local_port, cfg->endp_dscp, cfg->endp_priority); if (ret < 0) { LOGP(DOSMUX, LOGL_ERROR, "Cannot bind OSMUX IPv4 socket to %s:%u\n", cfg->osmux.local_addr_v4, cfg->osmux.local_port); return ret; } ret = osmo_fd_register(&osmux_fd_v4); if (ret < 0) { LOGP(DOSMUX, LOGL_ERROR, "Cannot register OSMUX IPv4 socket %s\n", osmo_sock_get_name2(osmux_fd_v4.fd)); return ret; } LOGP(DOSMUX, LOGL_INFO, "OSMUX IPv4 socket listening on %s\n", osmo_sock_get_name2(osmux_fd_v4.fd)); } if (cfg->osmux.local_addr_v6) { ret = mgcp_create_bind(cfg->osmux.local_addr_v6, &osmux_fd_v6, cfg->osmux.local_port, cfg->endp_dscp, cfg->endp_priority); if (ret < 0) { LOGP(DOSMUX, LOGL_ERROR, "Cannot bind OSMUX IPv6 socket to [%s]:%u\n", cfg->osmux.local_addr_v6, cfg->osmux.local_port); return ret; } ret = osmo_fd_register(&osmux_fd_v6); if (ret < 0) { LOGP(DOSMUX, LOGL_ERROR, "Cannot register OSMUX IPv6 socket %s\n", osmo_sock_get_name2(osmux_fd_v6.fd)); return ret; } LOGP(DOSMUX, LOGL_INFO, "OSMUX IPv6 socket listening on %s\n", osmo_sock_get_name2(osmux_fd_v6.fd)); } cfg->osmux.initialized = true; return 0; } /*! relase OSXMUX cid, that had been allocated to this connection. * \param[in] conn connection with OSMUX cid to release */ static void conn_osmux_release_local_cid(struct mgcp_conn_rtp *conn) { if (conn->osmux.local_cid_allocated) osmux_cid_pool_put(conn->osmux.local_cid); conn->osmux.local_cid = 0; conn->osmux.local_cid_allocated = false; } /*! allocate local OSMUX cid to connection. * \param[in] conn connection for which we allocate the local OSMUX cid * \returns Allocated OSMUX cid, -1 on error (no free CIDs avail). */ static int conn_osmux_allocate_local_cid(struct mgcp_conn_rtp *conn) { OSMO_ASSERT(conn->osmux.local_cid_allocated == false); int osmux_cid = osmux_cid_pool_get_next(); if (osmux_cid == -1) { LOGPCONN(conn->conn, DOSMUX, LOGL_INFO, "no available local Osmux CID to allocate!\n"); return -1; } conn->osmux.local_cid = (uint8_t) osmux_cid; conn->osmux.local_cid_allocated = true; return osmux_cid; } /*! Initialize Osmux bits of a conn. * \param[in] conn Osmux connection to initialize * \returns 0 on success, negative on ERROR */ int osmux_init_conn(struct mgcp_conn_rtp *conn) { if (conn_osmux_allocate_local_cid(conn) == -1) return -1; conn->osmux.ctrg = rate_ctr_group_alloc(conn->conn, &rate_ctr_group_osmux_desc, conn->ctrg->idx); conn->type = MGCP_RTP_OSMUX; /* Annotate Osmux circuit ID and set it to negotiating state until this * is fully set up from the dummy load. */ conn->osmux.state = OSMUX_STATE_ACTIVATING; return 0; } /*! enable OSXMUX circuit for a specified connection. * \param[in] conn connection to enable * \returns 0 on success, -1 on ERROR */ int conn_osmux_enable(struct mgcp_conn_rtp *conn) { OSMO_ASSERT(conn->osmux.state == OSMUX_STATE_ACTIVATING); OSMO_ASSERT(conn->osmux.remote_cid_present == true); /*! If osmux is enabled, initialize the output handler. This handler is * used to reconstruct the RTP flow from osmux. The RTP SSRC is * allocated based on the circuit ID (conn_net->osmux.cid), which is unique * in the local scope to the BSC/BSC-NAT. We use it to divide the RTP * SSRC space (2^32) by the OSMUX_CID_MAX + 1 possible circuit IDs, then randomly * select one value from that window. Thus, we have no chance to have * overlapping RTP SSRC traveling to the BTSes behind the BSC, * similarly, for flows traveling to the MSC. */ const struct mgcp_trunk *trunk = conn->conn->endp->trunk; static const uint32_t rtp_ssrc_winlen = UINT32_MAX / (OSMUX_CID_MAX + 1); bool osmux_dummy = trunk->cfg->osmux.dummy_padding; /* Wait until we have the remote connection information, be it from MDCX (peer not behind NAT) * or later learned from first received remote osmux packet (peer behind NAT) */ if (!mgcp_rtp_end_remote_addr_available(&conn->end)) { LOGPCONN(conn->conn, DOSMUX, LOGL_INFO, "Osmux remote address/port still unknown\n"); return -1; } conn->osmux.in = osmux_handle_find_or_create(trunk, &conn->end.addr); if (!conn->osmux.in) { LOGPCONN(conn->conn, DOSMUX, LOGL_ERROR, "Cannot allocate input osmux handle for conn:%s\n", mgcp_conn_dump(conn->conn)); return -1; } if (osmux_xfrm_input_open_circuit(conn->osmux.in, conn->osmux.remote_cid, osmux_dummy) < 0) { LOGPCONN(conn->conn, DOSMUX, LOGL_ERROR, "Cannot open osmux circuit %u for conn:%s\n", conn->osmux.remote_cid, mgcp_conn_dump(conn->conn)); return -1; } conn->osmux.out = osmux_xfrm_output_alloc(conn->conn); osmux_xfrm_output_set_rtp_ssrc(conn->osmux.out, (conn->osmux.remote_cid * rtp_ssrc_winlen) + (random() % rtp_ssrc_winlen)); osmux_xfrm_output_set_rtp_pl_type(conn->osmux.out, conn->end.codec->payload_type); osmux_xfrm_output_set_tx_cb(conn->osmux.out, scheduled_from_osmux_tx_rtp_cb, conn); conn->osmux.state = OSMUX_STATE_ENABLED; LOGPCONN(conn->conn, DOSMUX, LOGL_INFO, "Osmux CID %u towards %s is now enabled\n", conn->osmux.remote_cid, osmo_sockaddr_to_str(&conn->end.addr)); return 0; } /*! disable OSXMUX circuit for a specified connection. * \param[in] conn connection to disable */ void conn_osmux_disable(struct mgcp_conn_rtp *conn) { OSMO_ASSERT(conn->osmux.state != OSMUX_STATE_DISABLED); LOGPCONN(conn->conn, DOSMUX, LOGL_INFO, "Releasing connection using local Osmux CID %u\n", conn->osmux.local_cid); struct rate_ctr_group *all_osmux_stats = conn->conn->endp->trunk->ratectr.all_osmux_conn_stats; rate_ctr_inc(rate_ctr_group_get_ctr(all_osmux_stats, OSMUX_NUM_CONNECTIONS)); if (conn->osmux.state == OSMUX_STATE_ENABLED) { /* We are closing, we don't need pending RTP packets to be transmitted */ osmux_xfrm_output_set_tx_cb(conn->osmux.out, NULL, NULL); TALLOC_FREE(conn->osmux.out); osmux_xfrm_input_close_circuit(conn->osmux.in, conn->osmux.remote_cid); conn->osmux.state = OSMUX_STATE_DISABLED; osmux_handle_put(conn->osmux.in); conn->osmux.remote_cid = 0; conn->osmux.remote_cid_present = false; } conn_osmux_release_local_cid(conn); rate_ctr_group_free(conn->osmux.ctrg); conn->osmux.ctrg = NULL; } /*! send RTP dummy packet to OSMUX connection port. * \param[in] conn associated RTP connection * \returns bytes sent, -1 on error */ int osmux_send_dummy(struct mgcp_conn_rtp *conn) { char ipbuf[INET6_ADDRSTRLEN]; struct osmux_hdr *osmuxh; int buf_len; /*! The dummy packet will not be sent via the actual OSMUX connection, * instead it is sent out of band to port where the remote OSMUX * multplexer is listening. The goal is to ensure that the connection * is kept open */ /*! We don't need to send the dummy load for osmux so often as another * endpoint may have already punched the hole in the firewall. This * approach is simple though. */ buf_len = sizeof(struct osmux_hdr) + osmo_amr_bytes(AMR_FT_0); osmuxh = (struct osmux_hdr *) alloca(buf_len); memset(osmuxh, 0, buf_len); osmuxh->ft = OSMUX_FT_DUMMY; osmuxh->amr_ft = AMR_FT_0; osmuxh->circuit_id = conn->osmux.remote_cid; LOGPCONN(conn->conn, DOSMUX, LOGL_DEBUG, "sending OSMUX dummy load to %s:%u CID %u\n", osmo_sockaddr_ntop(&conn->end.addr.u.sa, ipbuf), osmo_sockaddr_port(&conn->end.addr.u.sa), conn->osmux.remote_cid); return mgcp_udp_send(osmux_fd_v4.fd, &conn->end.addr, (char *)osmuxh, buf_len); } /* Keeps track of locally allocated Osmux circuit ID. +7 to round up to 8 bit boundary. */ static uint8_t osmux_cid_bitmap[(OSMUX_CID_MAX + 1 + 7) / 8]; /*! count the number of taken OSMUX cids. * \returns number of OSMUX cids in use */ int osmux_cid_pool_count_used(void) { int i, j, used = 0; for (i = 0; i < sizeof(osmux_cid_bitmap); i++) { for (j = 0; j < 8; j++) { if (osmux_cid_bitmap[i] & (1 << j)) used += 1; } } return used; } /*! take a free OSMUX cid. * \returns OSMUX cid */ int osmux_cid_pool_get_next(void) { int i, j; for (i = 0; i < sizeof(osmux_cid_bitmap); i++) { for (j = 0; j < 8; j++) { if (osmux_cid_bitmap[i] & (1 << j)) continue; osmux_cid_bitmap[i] |= (1 << j); LOGP(DOSMUX, LOGL_DEBUG, "Allocating Osmux CID %u from pool\n", (i * 8) + j); return (i * 8) + j; } } LOGP(DOSMUX, LOGL_ERROR, "All Osmux circuits are in use!\n"); return -1; } /*! take a specific OSMUX cid. * \param[in] osmux_cid OSMUX cid */ void osmux_cid_pool_get(uint8_t osmux_cid) { LOGP(DOSMUX, LOGL_DEBUG, "Allocating Osmux CID %u from pool\n", osmux_cid); osmux_cid_bitmap[osmux_cid / 8] |= (1 << (osmux_cid % 8)); } /*! put back a no longer used OSMUX cid. * \param[in] osmux_cid OSMUX cid */ void osmux_cid_pool_put(uint8_t osmux_cid) { LOGP(DOSMUX, LOGL_DEBUG, "Osmux CID %u is back to the pool\n", osmux_cid); osmux_cid_bitmap[osmux_cid / 8] &= ~(1 << (osmux_cid % 8)); } /*! check if OSMUX cid is already taken */ bool osmux_cid_pool_allocated(uint8_t osmux_cid) { return !!(osmux_cid_bitmap[osmux_cid / 8] & (1 << (osmux_cid % 8))); }