diff options
Diffstat (limited to 'include/osmocom/isdn/lapd_core.h')
| -rw-r--r-- | include/osmocom/isdn/lapd_core.h | 192 |
1 files changed, 192 insertions, 0 deletions
diff --git a/include/osmocom/isdn/lapd_core.h b/include/osmocom/isdn/lapd_core.h new file mode 100644 index 00000000..1e010afe --- /dev/null +++ b/include/osmocom/isdn/lapd_core.h @@ -0,0 +1,192 @@ +/*! \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_flags */ +#define LAPD_F_RTS 0x0001 +#define LAPD_F_DROP_2ND_REJ 0x0002 + +/*! LAPD T200 state in RTS mode */ +enum lapd_t200_rts { + LAPD_T200_RTS_OFF = 0, + LAPD_T200_RTS_PENDING, + LAPD_T200_RTS_RUNNING, +}; + +/*! 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 */ + unsigned int lapd_flags; /*!< \ref lapd_flags to change processing */ + 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) */ + enum lapd_t200_rts t200_rts; /*!< state of T200 in RTS mode */ + 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_dl_set_flags(struct lapd_datalink *dl, unsigned int flags); +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_ph_rts_ind(struct lapd_msg_ctx *lctx); +int lapd_recv_dlsap(struct osmo_dlsap_prim *dp, struct lapd_msg_ctx *lctx); +int lapd_t200_timeout(struct lapd_datalink *dl); + +/*! @} */ |