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Diffstat (limited to 'include/openbsc/mgcp.h')
| -rw-r--r-- | include/openbsc/mgcp.h | 285 |
1 files changed, 285 insertions, 0 deletions
diff --git a/include/openbsc/mgcp.h b/include/openbsc/mgcp.h new file mode 100644 index 000000000..b2262bc8d --- /dev/null +++ b/include/openbsc/mgcp.h @@ -0,0 +1,285 @@ +/* A Media Gateway Control Protocol Media Gateway: RFC 3435 */ + +/* + * (C) 2009-2012 by Holger Hans Peter Freyther <zecke@selfish.org> + * (C) 2009-2012 by On-Waves + * All Rights 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. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU Affero General Public License for more details. + * + * You should have received a copy of the GNU Affero General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + * + */ + +#ifndef OPENBSC_MGCP_H +#define OPENBSC_MGCP_H + +#include <osmocom/core/msgb.h> +#include <osmocom/core/write_queue.h> +#include <osmocom/core/timer.h> + +#include "debug.h" + +#include <arpa/inet.h> +#include <sys/types.h> +#include <sys/socket.h> +#include <netinet/in.h> + +#define RTP_PORT_DEFAULT 4000 +#define RTP_PORT_NET_DEFAULT 16000 + +/** + * Calculate the RTP audio port for the given multiplex + * and the direction. This allows a semi static endpoint + * to port calculation removing the need for the BSC + * and the MediaGateway to communicate. + * + * Port usage explained: + * base + (multiplex * 2) + 0 == local port to wait for network packets + * base + (multiplex * 2) + 1 == local port for rtcp + * + * The above port will receive packets from the BTS that need + * to be patched and forwarded to the network. + * The above port will receive packets from the network that + * need to be patched and forwarded to the BTS. + * + * We assume to have a static BTS IP address so we can differentiate + * network and BTS. + * + */ +static inline int rtp_calculate_port(int multiplex, int base) +{ + return base + (multiplex * 2); +} + + +/* + * Handling of MGCP Endpoints and the MGCP Config + */ +struct mgcp_endpoint; +struct mgcp_config; +struct mgcp_trunk_config; +struct mgcp_rtp_end; + +#define MGCP_ENDP_CRCX 1 +#define MGCP_ENDP_DLCX 2 +#define MGCP_ENDP_MDCX 3 + +/* + * what to do with the msg? + * - continue as usual? + * - reject and send a failure code? + * - defer? do not send anything + */ +#define MGCP_POLICY_CONT 4 +#define MGCP_POLICY_REJECT 5 +#define MGCP_POLICY_DEFER 6 + +typedef int (*mgcp_realloc)(struct mgcp_trunk_config *cfg, int endpoint); +typedef int (*mgcp_change)(struct mgcp_trunk_config *cfg, int endpoint, int state); +typedef int (*mgcp_policy)(struct mgcp_trunk_config *cfg, int endpoint, int state, const char *transactio_id); +typedef int (*mgcp_reset)(struct mgcp_trunk_config *cfg); +typedef int (*mgcp_rqnt)(struct mgcp_endpoint *endp, char tone); + +/** + * Return: + * < 0 in case no audio was processed + * >= 0 in case audio was processed. The remaining payload + * length will be returned. + */ +typedef int (*mgcp_processing)(struct mgcp_endpoint *endp, + struct mgcp_rtp_end *dst_end, + char *data, int *len, int buf_size); +typedef int (*mgcp_processing_setup)(struct mgcp_endpoint *endp, + struct mgcp_rtp_end *dst_end, + struct mgcp_rtp_end *src_end); + +typedef void (*mgcp_get_format)(struct mgcp_endpoint *endp, + int *payload_type, + const char**subtype_name, + const char**fmtp_extra); + +#define PORT_ALLOC_STATIC 0 +#define PORT_ALLOC_DYNAMIC 1 + +/** + * This holds information on how to allocate ports + */ +struct mgcp_port_range { + int mode; + + /* addr or NULL to fall-back to default */ + char *bind_addr; + + /* pre-allocated from a base? */ + int base_port; + + /* dynamically allocated */ + int range_start; + int range_end; + int last_port; +}; + +#define MGCP_KEEPALIVE_ONCE (-1) + +struct mgcp_trunk_config { + struct llist_head entry; + + struct mgcp_config *cfg; + + int trunk_nr; + int trunk_type; + + char *audio_fmtp_extra; + char *audio_name; + int audio_payload; + int audio_send_ptime; + int audio_send_name; + int audio_loop; + + int no_audio_transcoding; + + int omit_rtcp; + int keepalive_interval; + + /* RTP patching */ + int force_constant_ssrc; /* 0: don't, 1: once */ + int force_aligned_timing; + + /* spec handling */ + int force_realloc; + + /* timer */ + struct osmo_timer_list keepalive_timer; + + unsigned int number_endpoints; + struct mgcp_endpoint *endpoints; +}; + +enum mgcp_role { + MGCP_BSC = 0, + MGCP_BSC_NAT, +}; + +struct mgcp_config { + int source_port; + char *local_ip; + char *source_addr; + char *bts_ip; + char *call_agent_addr; + + struct in_addr bts_in; + + /* transcoder handling */ + char *transcoder_ip; + struct in_addr transcoder_in; + int transcoder_remote_base; + + /* RTP processing */ + mgcp_processing rtp_processing_cb; + mgcp_processing_setup setup_rtp_processing_cb; + + mgcp_get_format get_net_downlink_format_cb; + + struct osmo_wqueue gw_fd; + + struct mgcp_port_range bts_ports; + struct mgcp_port_range net_ports; + struct mgcp_port_range transcoder_ports; + int endp_dscp; + + int bts_force_ptime; + + mgcp_change change_cb; + mgcp_policy policy_cb; + mgcp_reset reset_cb; + mgcp_realloc realloc_cb; + mgcp_rqnt rqnt_cb; + void *data; + + uint32_t last_call_id; + + /* trunk handling */ + struct mgcp_trunk_config trunk; + struct llist_head trunks; + + /* only used for start with a static configuration */ + int last_net_port; + int last_bts_port; + + enum mgcp_role role; + + /* osmux translator: 0 means disabled, 1 means enabled */ + int osmux; + /* addr to bind the server to */ + char *osmux_addr; + /* The BSC-NAT may ask for enabling osmux on demand. This tells us if + * the osmux socket is already initialized. + */ + int osmux_init; + /* osmux batch factor: from 1 to 4 maximum */ + int osmux_batch; + /* osmux batch size (in bytes) */ + int osmux_batch_size; + /* osmux port */ + uint16_t osmux_port; + /* Pad circuit with dummy messages until we see the first voice + * message. + */ + uint16_t osmux_dummy; +}; + +/* config management */ +struct mgcp_config *mgcp_config_alloc(void); +int mgcp_parse_config(const char *config_file, struct mgcp_config *cfg, + enum mgcp_role role); +int mgcp_vty_init(void); +int mgcp_endpoints_allocate(struct mgcp_trunk_config *cfg); +void mgcp_release_endp(struct mgcp_endpoint *endp); +void mgcp_initialize_endp(struct mgcp_endpoint *endp); +int mgcp_reset_transcoder(struct mgcp_config *cfg); +void mgcp_format_stats(struct mgcp_endpoint *endp, char *stats, size_t size); +int mgcp_parse_stats(struct msgb *msg, uint32_t *ps, uint32_t *os, uint32_t *pr, uint32_t *_or, int *loss, uint32_t *jitter); + +void mgcp_trunk_set_keepalive(struct mgcp_trunk_config *tcfg, int interval); + +/* + * format helper functions + */ +struct msgb *mgcp_handle_message(struct mgcp_config *cfg, struct msgb *msg); + +/* adc helper */ +static inline int mgcp_timeslot_to_endpoint(int multiplex, int timeslot) +{ + if (timeslot == 0) { + LOGP(DMGCP, LOGL_ERROR, "Timeslot should not be 0\n"); + timeslot = 255; + } + + return timeslot + (32 * multiplex); +} + +static inline void mgcp_endpoint_to_timeslot(int endpoint, int *multiplex, int *timeslot) +{ + *multiplex = endpoint / 32; + *timeslot = endpoint % 32; +} + +int mgcp_send_reset_ep(struct mgcp_endpoint *endp, int endpoint); +int mgcp_send_reset_all(struct mgcp_config *cfg); + + +int mgcp_create_bind(const char *source_addr, struct osmo_fd *fd, int port); +int mgcp_send(struct mgcp_endpoint *endp, int dest, int is_rtp, struct sockaddr_in *addr, char *buf, int rc); +int mgcp_udp_send(int fd, struct in_addr *addr, int port, char *buf, int len); + +#endif |