| /* |
| * (C) 2012-2013 by Pablo Neira Ayuso <pablo@gnumonks.org> |
| * (C) 2012-2013 by On Waves ehf <http://www.on-waves.com> |
| * 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 <stdio.h> /* for printf */ |
| #include <string.h> /* for memcpy */ |
| #include <stdlib.h> /* for abs */ |
| #include <inttypes.h> /* for PRIu64 */ |
| #include <netinet/in.h> |
| #include <osmocom/core/msgb.h> |
| #include <osmocom/core/socket.h> |
| #include <osmocom/core/talloc.h> |
| |
| #include <osmocom/netif/osmux.h> |
| #include <osmocom/netif/rtp.h> |
| #include <osmocom/netif/amr.h> |
| |
| #include <osmocom/mgcp/debug.h> |
| #include <osmocom/mgcp/mgcp.h> |
| #include <osmocom/mgcp/mgcp_protocol.h> |
| #include <osmocom/mgcp/osmux.h> |
| #include <osmocom/mgcp/mgcp_conn.h> |
| #include <osmocom/mgcp/mgcp_endp.h> |
| #include <osmocom/mgcp/mgcp_trunk.h> |
| |
| 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; |
| char name[128] = "r="; |
| |
| 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; |
| } |
| |
| osmo_sockaddr_to_str_buf(name + 2, sizeof(name) - 2, rem_addr); |
| osmux_xfrm_input_set_name(h->in, name); |
| /* 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; |
| |
| /* Osmux implementation works with AMR OA only, make sure we convert to it if needed: */ |
| if (amr_oa_bwe_convert(conn->conn->endp, msg2, true) < 0) { |
| LOGPCONN(conn->conn, DOSMUX, LOGL_ERROR, |
| "Error converting to AMR octet-aligned mode\n"); |
| 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<CID>] 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; |
| } |
| |
| /*! Find and reserve a free OSMUX cid. Keep state of last allocated CID to |
| * rotate allocated CIDs over time. This helps in letting CIDs unused for some |
| * time after last use. |
| * \returns OSMUX cid */ |
| int osmux_cid_pool_get_next(void) |
| { |
| static uint8_t next_free_osmux_cid_lookup = 0; |
| uint8_t start_i, start_j; |
| uint8_t i, j, cid; |
| |
| /* i = octet index, j = bit index inside ith octet */ |
| start_i = next_free_osmux_cid_lookup >> 3; |
| start_j = next_free_osmux_cid_lookup & 0x07; |
| |
| for (i = start_i; i < sizeof(osmux_cid_bitmap); i++) { |
| for (j = start_j; j < 8; j++) { |
| if (osmux_cid_bitmap[i] & (1 << j)) |
| continue; |
| goto found; |
| } |
| } |
| |
| for (i = 0; i <= start_i; i++) { |
| for (j = 0; j < start_j; j++) { |
| if (osmux_cid_bitmap[i] & (1 << j)) |
| continue; |
| goto found; |
| } |
| } |
| |
| LOGP(DOSMUX, LOGL_ERROR, "All Osmux circuits are in use!\n"); |
| return -1; |
| |
| found: |
| osmux_cid_bitmap[i] |= (1 << j); |
| cid = (i << 3) | j; |
| next_free_osmux_cid_lookup = (cid + 1) & 0xff; |
| LOGP(DOSMUX, LOGL_DEBUG, |
| "Allocating Osmux CID %u from pool\n", cid); |
| return cid; |
| } |
| |
| /*! 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))); |
| } |