include/osmocom/mgcp_client/mgcp_client.h

#pragma once

#include <stdint.h>
#include <arpa/inet.h>

#include <osmocom/mgcp_client/mgcp_common.h>

/* See also: RFC 3435, chapter 3.5 Transmission over UDP */
#define MGCP_CLIENT_LOCAL_ADDR_DEFAULT NULL /* INADDR(6)_ANY */
#define MGCP_CLIENT_LOCAL_PORT_DEFAULT 2727
#define MGCP_CLIENT_REMOTE_ADDR_DEFAULT "127.0.0.1"
#define MGCP_CLIENT_REMOTE_PORT_DEFAULT 2427

#define MGCP_CLIENT_MGW_STR "Configure MGCP connection to Media Gateway\n"

struct msgb;
struct vty;
struct mgcp_client;

struct mgcp_client_conf {
	const char *local_addr;
	int local_port;
	const char *remote_addr;
	int remote_port;

	/* By default, we are always addressing the MGW with e.g. 'rtpbridge/123@mgw'.
	 * If this is nonempty, the contained name will be used instead of 'mgw'. */
	char endpoint_domain_name[MGCP_ENDPOINT_MAXLEN];

	/* The user may configure certain endpoint names that are reset via DLCX
	 * on startup. Usually this will be one wildcarded endpoint e.g.
	 * 'rtpbridge/(wildcard)' or a number of specific E1 like e.g.
	 * 'ds/e1-0/s-3/su16-4' */
	struct llist_head reset_epnames;

	/* human readable name / description */
	char *description;
};

typedef unsigned int mgcp_trans_id_t;

/*! Enumeration of the codec types that mgcp_client is able to handle. */
enum mgcp_codecs {
	CODEC_PCMU_8000_1 = 0,
	CODEC_GSM_8000_1 = 3,
	CODEC_PCMA_8000_1 = 8,
	CODEC_G729_8000_1 = 18,
	CODEC_GSMEFR_8000_1 = 110,
	CODEC_GSMHR_8000_1 = 111,
	CODEC_AMR_8000_1 = 112,
	CODEC_AMRWB_16000_1 = 113,
};
/* Note: when new codec types are added, the corresponding value strings
 * in mgcp_client.c (codec_table) must be updated as well. Enumerations
 * in enum mgcp_codecs must correspond to a valid payload type. However,
 * this is an internal assumption that is made to avoid lookup tables.
 * The API-User should not rely on this coincidence! */

extern const struct value_string osmo_mgcpc_codec_names[];
static inline const char *osmo_mgcpc_codec_name(enum mgcp_codecs val)
{ return get_value_string(osmo_mgcpc_codec_names, val); }

/*! Structure to build a payload type map to allow the defiition custom payload
 *  types. */
struct ptmap {
	/*! codec for which a payload type number should be defined */
	enum mgcp_codecs codec;

	/*! payload type number (96-127) */
	unsigned int pt;
};

struct mgcp_response_head {
	int response_code;
	mgcp_trans_id_t trans_id;
	char comment[MGCP_COMMENT_MAXLEN];
	char conn_id[MGCP_CONN_ID_MAXLEN];
	char endpoint[MGCP_ENDPOINT_MAXLEN];
	bool x_osmo_osmux_use;
	uint8_t x_osmo_osmux_cid;
};

struct mgcp_response {
	char *body;
	struct mgcp_response_head head;
	uint16_t audio_port;
	char audio_ip[INET6_ADDRSTRLEN];
	unsigned int ptime;
	enum mgcp_codecs codecs[MGCP_MAX_CODECS];
	unsigned int codecs_len;
	struct ptmap ptmap[MGCP_MAX_CODECS];
	unsigned int ptmap_len;
};

enum mgcp_verb {
	MGCP_VERB_CRCX,
	MGCP_VERB_MDCX,
	MGCP_VERB_DLCX,
	MGCP_VERB_AUEP,
	MGCP_VERB_RSIP,
};

#define MGCP_MSG_PRESENCE_ENDPOINT	0x0001
#define MGCP_MSG_PRESENCE_CALL_ID	0x0002
#define MGCP_MSG_PRESENCE_CONN_ID	0x0004
#define MGCP_MSG_PRESENCE_AUDIO_IP	0x0008
#define MGCP_MSG_PRESENCE_AUDIO_PORT	0x0010
#define MGCP_MSG_PRESENCE_CONN_MODE	0x0020
#define MGCP_MSG_PRESENCE_X_OSMO_OSMUX_CID 0x4000
#define MGCP_MSG_PRESENCE_X_OSMO_IGN	0x8000

struct mgcp_msg {
	enum mgcp_verb verb;
	/* See MGCP_MSG_PRESENCE_* constants */
	uint32_t presence;
	char endpoint[MGCP_ENDPOINT_MAXLEN];
	unsigned int call_id;
	char *conn_id;
	uint16_t audio_port;
	char *audio_ip;
	enum mgcp_connection_mode conn_mode;
	unsigned int ptime;
	enum mgcp_codecs codecs[MGCP_MAX_CODECS];
	unsigned int codecs_len;
	struct ptmap ptmap[MGCP_MAX_CODECS];
	unsigned int ptmap_len;
	uint32_t x_osmo_ign;
	bool x_osmo_osmux_use;
	int x_osmo_osmux_cid; /* -1 is wildcard */
	bool param_present;
	struct mgcp_codec_param param;
};

void mgcp_client_conf_init(struct mgcp_client_conf *conf);
void mgcp_client_vty_init(void *talloc_ctx, int node, struct mgcp_client_conf *conf);
int mgcp_client_config_write(struct vty *vty, const char *indent);
struct mgcp_client_conf *mgcp_client_conf_actual(struct mgcp_client *mgcp);

struct mgcp_client *mgcp_client_init(void *ctx,
				     struct mgcp_client_conf *conf);
int mgcp_client_connect(struct mgcp_client *mgcp);
int mgcp_client_connect2(struct mgcp_client *mgcp, unsigned int retry_n_ports);
void mgcp_client_disconnect(struct mgcp_client *mgcp);

const char *mgcp_client_remote_addr_str(struct mgcp_client *mgcp);
uint16_t mgcp_client_remote_port(struct mgcp_client *mgcp);
uint32_t mgcp_client_remote_addr_n(struct mgcp_client *mgcp) OSMO_DEPRECATED("deprecated, returns 0");

const char *mgcp_client_endpoint_domain(const struct mgcp_client *mgcp);
const char *mgcp_client_rtpbridge_wildcard(const struct mgcp_client *mgcp);
const char *mgcp_client_e1_epname(void *ctx, const struct mgcp_client *mgcp, uint8_t trunk_id, uint8_t ts,
				  uint8_t rate, uint8_t offset);

/* Invoked when an MGCP response is received or sending failed.  When the
 * response is passed as NULL, this indicates failure during transmission. */
typedef void (* mgcp_response_cb_t )(struct mgcp_response *response, void *priv);
int mgcp_response_parse_params(struct mgcp_response *r);

int mgcp_client_tx(struct mgcp_client *mgcp, struct msgb *msg,
		   mgcp_response_cb_t response_cb, void *priv);
int mgcp_client_cancel(struct mgcp_client *mgcp, mgcp_trans_id_t trans_id);

enum mgcp_connection_mode;

struct msgb *mgcp_msg_gen(struct mgcp_client *mgcp, struct mgcp_msg *mgcp_msg);
mgcp_trans_id_t mgcp_msg_trans_id(struct msgb *msg);

extern const struct value_string mgcp_client_connection_mode_strs[];
static inline const char *mgcp_client_cmode_name(enum mgcp_connection_mode mode)
{
	return get_value_string(mgcp_client_connection_mode_strs, mode);
}

enum mgcp_codecs map_str_to_codec(const char *str);
unsigned int map_codec_to_pt(const struct ptmap *ptmap, unsigned int ptmap_len,
			     enum mgcp_codecs codec);
enum mgcp_codecs map_pt_to_codec(struct ptmap *ptmap, unsigned int ptmap_len,
				 unsigned int pt);

const char *mgcp_client_name(const struct mgcp_client *mgcp);