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/*! \file lapd_core.h
* primitive related stuff
*/
#pragma once
#include <stdint.h>
#include <osmocom/core/timer.h>
#include <osmocom/core/msgb.h>
#include <osmocom/gsm/prim.h>
/*! \defgroup lapd LAPD implementation common part
* @{
* \file lapd_core.h
*/
#define LOGDL(dl, level, fmt, args...) \
LOGP(DLLAPD, level, "(%s) " fmt, (dl)->name, ## args)
/*! LAPD related primitives (L2<->L3 SAP)*/
enum osmo_dl_prim {
PRIM_DL_UNIT_DATA, /*!< DL-UNIT-DATA */
PRIM_DL_DATA, /*!< DL-DATA */
PRIM_DL_EST, /*!< DL-ESTABLISH */
PRIM_DL_REL, /*!< DL-RLEEASE */
PRIM_DL_SUSP, /*!< DL-SUSPEND */
PRIM_DL_RES, /*!< DL-RESUME */
PRIM_DL_RECON, /*!< DL-RECONNECT */
PRIM_MDL_ERROR, /*!< MDL-ERROR */
};
/* Uses the same values as RLL, so no conversion for GSM is required. */
#define MDL_CAUSE_T200_EXPIRED 0x01
#define MDL_CAUSE_REEST_REQ 0x02
#define MDL_CAUSE_UNSOL_UA_RESP 0x03
#define MDL_CAUSE_UNSOL_DM_RESP 0x04
#define MDL_CAUSE_UNSOL_DM_RESP_MF 0x05
#define MDL_CAUSE_UNSOL_SPRV_RESP 0x06
#define MDL_CAUSE_SEQ_ERR 0x07
#define MDL_CAUSE_UFRM_INC_PARAM 0x08
#define MDL_CAUSE_SFRM_INC_PARAM 0x09
#define MDL_CAUSE_IFRM_INC_MBITS 0x0a
#define MDL_CAUSE_IFRM_INC_LEN 0x0b
#define MDL_CAUSE_FRM_UNIMPL 0x0c
#define MDL_CAUSE_SABM_MF 0x0d
#define MDL_CAUSE_SABM_INFO_NOTALL 0x0e
#define MDL_CAUSE_FRMR 0x0f
/*! for MDL-ERROR.ind */
struct mdl_error_ind_param {
uint8_t cause; /*!< generic cause value */
};
/*! for DL-REL.req */
struct dl_rel_req_param {
uint8_t mode; /*!< release mode */
};
/*! primitive header for LAPD DL-SAP primitives */
struct osmo_dlsap_prim {
struct osmo_prim_hdr oph; /*!< generic primitive header */
union {
struct mdl_error_ind_param error_ind;
struct dl_rel_req_param rel_req;
} u; /*!< request-specific data */
};
/*! LAPD mode/role */
enum lapd_mode {
LAPD_MODE_USER, /*!< behave like user */
LAPD_MODE_NETWORK, /*!< behave like network */
};
/*! LAPD state (Figure B.2/Q.921)*/
enum lapd_state {
LAPD_STATE_NULL = 0,
LAPD_STATE_TEI_UNASS,
LAPD_STATE_ASS_TEI_WAIT,
LAPD_STATE_EST_TEI_WAIT,
LAPD_STATE_IDLE,
LAPD_STATE_SABM_SENT,
LAPD_STATE_DISC_SENT,
LAPD_STATE_MF_EST,
LAPD_STATE_TIMER_RECOV,
};
/*! LAPD message format (I / S / U) */
enum lapd_format {
LAPD_FORM_UKN = 0,
LAPD_FORM_I,
LAPD_FORM_S,
LAPD_FORM_U,
};
/*! LAPD message context */
struct lapd_msg_ctx {
struct lapd_datalink *dl;
int n201;
/* address */
uint8_t cr;
uint8_t sapi;
uint8_t tei;
uint8_t lpd;
/* control */
uint8_t format;
uint8_t p_f; /* poll / final bit */
uint8_t n_send;
uint8_t n_recv;
uint8_t s_u; /* S or repectivly U function bits */
/* length */
int length;
uint8_t more;
};
struct lapd_cr_ent {
uint8_t cmd;
uint8_t resp;
};
struct lapd_history {
struct msgb *msg; /* message to be sent / NULL, if histoy is empty */
int more; /* if message is fragmented */
};
/*! LAPD datalink */
struct lapd_datalink {
int (*send_dlsap)(struct osmo_dlsap_prim *dp,
struct lapd_msg_ctx *lctx);
int (*send_ph_data_req)(struct lapd_msg_ctx *lctx, struct msgb *msg);
int (*update_pending_frames)(struct lapd_msg_ctx *lctx);
struct {
/*! filled-in once we set the lapd_mode above */
struct lapd_cr_ent loc2rem;
struct lapd_cr_ent rem2loc;
} cr;
enum lapd_mode mode; /*!< current mode of link */
int use_sabme; /*!< use SABME instead of SABM */
int reestablish; /*!< enable reestablish support */
int n200, n200_est_rel; /*!< number of retranmissions */
struct lapd_msg_ctx lctx; /*!< LAPD context */
int maxf; /*!< maximum frame size (after defragmentation) */
uint8_t k; /*!< maximum number of unacknowledged frames */
uint8_t v_range; /*!< range of sequence numbers */
uint8_t v_send; /*!< seq nr of next I frame to be transmitted */
uint8_t v_ack; /*!< last frame ACKed by peer */
uint8_t v_recv; /*!< seq nr of next I frame expected to be received */
uint32_t state; /*!< LAPD state (\ref lapd_state) */
int seq_err_cond; /*!< condition of sequence error */
uint8_t own_busy; /*!< receiver busy on our side */
uint8_t peer_busy; /*!< receiver busy on remote side */
int t200_sec, t200_usec; /*!< retry timer (default 1 sec) */
int t203_sec, t203_usec; /*!< retry timer (default 10 secs) */
struct osmo_timer_list t200; /*!< T200 timer */
struct osmo_timer_list t203; /*!< T203 timer */
uint8_t retrans_ctr; /*!< re-transmission counter */
struct llist_head tx_queue; /*!< frames to L1 */
struct llist_head send_queue; /*!< frames from L3 */
struct msgb *send_buffer; /*!< current frame transmitting */
int send_out; /*!< how much was sent from send_buffer */
struct lapd_history *tx_hist; /*!< tx history structure array */
uint8_t range_hist; /*!< range of history buffer 2..2^n */
struct msgb *rcv_buffer; /*!< buffer to assemble the received message */
struct msgb *cont_res; /*!< buffer to store content resolution data on network side, to detect multiple phones on same channel */
char *name; /*!< user-provided name */
};
void lapd_dl_init(struct lapd_datalink *dl, uint8_t k, uint8_t v_range, int maxf)
OSMO_DEPRECATED("Use lapd_dl_init2() instead");
void lapd_dl_init2(struct lapd_datalink *dl, uint8_t k, uint8_t v_range, int maxf, const char *name);
void lapd_dl_set_name(struct lapd_datalink *dl, const char *name);
void lapd_dl_exit(struct lapd_datalink *dl);
void lapd_dl_reset(struct lapd_datalink *dl);
int lapd_set_mode(struct lapd_datalink *dl, enum lapd_mode mode);
int lapd_ph_data_ind(struct msgb *msg, struct lapd_msg_ctx *lctx);
int lapd_recv_dlsap(struct osmo_dlsap_prim *dp, struct lapd_msg_ctx *lctx);
/*! @} */
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