/* BSSGP per-BVC Finite State Machine */ /* (C) 2020 Harald Welte * * All Rights Reserved * * SPDX-License-Identifier: GPL-2.0+ * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 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 General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program. If not, see . * */ #include #include #include #include #include #include #include #include #include #include #include #include #include "common_vty.h" #define S(x) (1 << (x)) /* TODO: Those are not made cofnigurable via a VTY yet */ struct osmo_tdef bssgp_bvc_fsm_tdefs[] = { { .T = 1, .default_val = 5, .min_val = 1, .max_val = 30, .unit = OSMO_TDEF_S, .desc = "Guards the BSSGP BVC (un)blocking procedure", }, { .T = 2, .default_val = 10, .min_val = 1, .max_val = 120, .unit = OSMO_TDEF_S, .desc = "Guards the BSSGP BVC reset procedure", }, { .T = 3, .default_val = 500, .min_val = 100, .max_val = 10000, .unit = OSMO_TDEF_MS, .desc = "Guards the BSSGP SUSPEND procedure", }, { .T = 4, .default_val = 500, .min_val = 100, .max_val = 10000, .unit = OSMO_TDEF_MS, .desc = "Guards the BSSGP RESUME procedure", }, { .T = 5, .default_val = 15, .min_val = 1, .max_val = 30, .unit = OSMO_TDEF_S, .desc = "Guards the BSSGP Radio Access Capability Update procedure", }, {} }; #define T1 1 #define T2 2 /* We cannot use osmo_tdef_fsm_* as it makes hard-coded assumptions that * each new/target state will always use the same timer and timeout - or * a timeout at all */ #define T1_SECS osmo_tdef_get(bssgp_bvc_fsm_tdefs, 1, OSMO_TDEF_S, 5) #define T2_SECS osmo_tdef_get(bssgp_bvc_fsm_tdefs, 2, OSMO_TDEF_S, 10) /* forward declaration */ static struct osmo_fsm bssgp_bvc_fsm; static const struct value_string ptp_bvc_event_names[] = { { BSSGP_BVCFSM_E_RX_BLOCK, "RX-BVC-BLOCK" }, { BSSGP_BVCFSM_E_RX_BLOCK_ACK, "RX-BVC-BLOCK-ACK" }, { BSSGP_BVCFSM_E_RX_UNBLOCK, "RX-BVC-UNBLOCK" }, { BSSGP_BVCFSM_E_RX_UNBLOCK_ACK, "RX-BVC-UNBLOCK-ACK" }, { BSSGP_BVCFSM_E_RX_RESET, "RX-BVC-RESET" }, { BSSGP_BVCFSM_E_RX_RESET_ACK, "RX-BVC-RESET-ACK" }, { BSSGP_BVCFSM_E_RX_FC_BVC, "RX-FLOW-CONTROL-BVC" }, { BSSGP_BVCFSM_E_RX_FC_BVC_ACK, "RX-FLOW-CONTROL-BVC-ACK" }, { BSSGP_BVCFSM_E_REQ_BLOCK, "REQ-BLOCK" }, { BSSGP_BVCFSM_E_REQ_UNBLOCK, "REQ-UNBLOCK" }, { BSSGP_BVCFSM_E_REQ_RESET, "REQ-RESET" }, { BSSGP_BVCFSM_E_REQ_FC_BVC, "REQ-FLOW-CONTROL-BVC" }, { 0, NULL } }; struct bvc_fsm_priv { /* NS-instance; defining the scope for NSEI below */ struct gprs_ns2_inst *nsi; /* NSEI of the underlying NS Entity */ uint16_t nsei; /* Maximum size of the BSSGP PDU */ uint16_t max_pdu_len; /* BVCI of this BVC */ uint16_t bvci; /* are we the SGSN (true) or the BSS (false) */ bool role_sgsn; /* BSS side: are we locally marked blocked? */ bool locally_blocked; uint8_t block_cause; /* cause value of the last outbound BVC-RESET (for re-transmissions) */ uint8_t last_reset_cause; struct { /* Bit 0..7: Features; Bit 8..15: Extended Features */ uint32_t advertised; uint32_t received; uint32_t negotiated; /* only used if BSSGP_XFEAT_GBIT is negotiated */ enum bssgp_fc_granularity fc_granularity; } features; /* Cell Identification used by BSS when * transmitting BVC-RESET / BVC-RESET-ACK, or those received * from BSS in SGSN role */ struct gprs_ra_id ra_id; uint16_t cell_id; /* call-backs provided by the user */ const struct bssgp_bvc_fsm_ops *ops; /* private data pointer passed to each call-back invocation */ void *ops_priv; }; static int fi_tx_ptp(struct osmo_fsm_inst *fi, struct msgb *msg) { struct bssgp_normal_hdr *bgph = (struct bssgp_normal_hdr *) msgb_bssgph(msg); struct bvc_fsm_priv *bfp = fi->priv; OSMO_ASSERT(fi->fsm == &bssgp_bvc_fsm); LOGPFSM(fi, "Tx BSSGP %s\n", osmo_tlv_prot_msg_name(&osmo_pdef_bssgp, bgph->pdu_type)); return bssgp2_nsi_tx_ptp(bfp->nsi, bfp->nsei, bfp->bvci, msg, 0); } static int fi_tx_sig(struct osmo_fsm_inst *fi, struct msgb *msg) { struct bssgp_normal_hdr *bgph = (struct bssgp_normal_hdr *) msgb_bssgph(msg); struct bvc_fsm_priv *bfp = fi->priv; OSMO_ASSERT(fi->fsm == &bssgp_bvc_fsm); LOGPFSM(fi, "Tx BSSGP %s\n", osmo_tlv_prot_msg_name(&osmo_pdef_bssgp, bgph->pdu_type)); return bssgp2_nsi_tx_sig(bfp->nsi, bfp->nsei, msg, 0); } /* helper function to transmit BVC-RESET with right combination of conditional/optional IEs */ static void _tx_bvc_reset(struct osmo_fsm_inst *fi, uint8_t cause) { struct bvc_fsm_priv *bfp = fi->priv; const uint8_t *features = NULL; const uint8_t *features_ext = NULL; uint8_t _features[2] = { (bfp->features.advertised >> 0) & 0xff, (bfp->features.advertised >> 8) & 0xff, }; struct msgb *tx; OSMO_ASSERT(fi->fsm == &bssgp_bvc_fsm); /* transmit BVC-RESET to peer; RA-ID only present for PTP from BSS */ if (bfp->bvci == 0) { features = &_features[0]; features_ext = &_features[1]; } tx = bssgp2_enc_bvc_reset(bfp->bvci, cause, bfp->bvci && !bfp->role_sgsn ? &bfp->ra_id : NULL, bfp->cell_id, features, features_ext); fi_tx_sig(fi, tx); } /* helper function to transmit BVC-RESET-ACK with right combination of conditional/optional IEs */ static void _tx_bvc_reset_ack(struct osmo_fsm_inst *fi) { struct bvc_fsm_priv *bfp = fi->priv; const uint8_t *features = NULL; const uint8_t *features_ext = NULL; uint8_t _features[2] = { (bfp->features.advertised >> 0) & 0xff, (bfp->features.advertised >> 8) & 0xff, }; struct msgb *tx; OSMO_ASSERT(fi->fsm == &bssgp_bvc_fsm); /* transmit BVC-RESET-ACK to peer; RA-ID only present for PTP from BSS -> SGSN */ if (bfp->bvci == 0) { features = &_features[0]; features_ext = &_features[1]; } tx = bssgp2_enc_bvc_reset_ack(bfp->bvci, bfp->bvci && !bfp->role_sgsn ? &bfp->ra_id : NULL, bfp->cell_id, features, features_ext); fi_tx_sig(fi, tx); } /* helper function to transmit BVC-STATUS with right combination of conditional/optional IEs */ static void _tx_status(struct osmo_fsm_inst *fi, enum gprs_bssgp_cause cause, const struct msgb *rx) { struct bvc_fsm_priv *bfp = fi->priv; struct msgb *tx; uint16_t *bvci = NULL; /* GSM 08.18, 10.4.14.1: The BVCI must be included if (and only if) the * cause is either "BVCI blocked" or "BVCI unknown" */ if (cause == BSSGP_CAUSE_UNKNOWN_BVCI || cause == BSSGP_CAUSE_BVCI_BLOCKED) bvci = &bfp->bvci; tx = bssgp2_enc_status(cause, bvci, rx, bfp->max_pdu_len); if (msgb_bvci(rx) == 0) fi_tx_sig(fi, tx); else fi_tx_ptp(fi, tx); } /* Update the features by bit-wise AND of advertised + received features */ static void update_negotiated_features(struct osmo_fsm_inst *fi, const struct tlv_parsed *tp) { struct bvc_fsm_priv *bfp = fi->priv; OSMO_ASSERT(fi->fsm == &bssgp_bvc_fsm); bfp->features.received = 0; if (TLVP_PRES_LEN(tp, BSSGP_IE_FEATURE_BITMAP, 1)) bfp->features.received |= *TLVP_VAL(tp, BSSGP_IE_FEATURE_BITMAP); if (TLVP_PRES_LEN(tp, BSSGP_IE_EXT_FEATURE_BITMAP, 1)) bfp->features.received |= (*TLVP_VAL(tp, BSSGP_IE_EXT_FEATURE_BITMAP) << 8); bfp->features.negotiated = bfp->features.advertised & bfp->features.received; LOGPFSML(fi, LOGL_NOTICE, "Updating features: Advertised 0x%04x, Received 0x%04x, Negotiated 0x%04x\n", bfp->features.advertised, bfp->features.received, bfp->features.negotiated); } /* "tail" of each onenter() handler: Calling the state change notification call-back */ static void _onenter_tail(struct osmo_fsm_inst *fi, uint32_t prev_state) { struct bvc_fsm_priv *bfp = fi->priv; if (prev_state == fi->state) return; if (bfp->ops && bfp->ops->state_chg_notification) bfp->ops->state_chg_notification(bfp->nsei, bfp->bvci, prev_state, fi->state, bfp->ops_priv); } static void bssgp_bvc_fsm_null(struct osmo_fsm_inst *fi, uint32_t event, void *data) { /* we don't really expect anything in this state; all handled via allstate */ OSMO_ASSERT(0); } static void bssgp_bvc_fsm_blocked_onenter(struct osmo_fsm_inst *fi, uint32_t prev_state) { struct bvc_fsm_priv *bfp = fi->priv; /* signaling BVC can never be blocked */ OSMO_ASSERT(bfp->bvci != 0); _onenter_tail(fi, prev_state); } static void bssgp_bvc_fsm_blocked(struct osmo_fsm_inst *fi, uint32_t event, void *data) { struct bvc_fsm_priv *bfp = fi->priv; struct msgb *rx = NULL, *tx; const struct tlv_parsed *tp = NULL; uint8_t cause; switch (event) { case BSSGP_BVCFSM_E_RX_BLOCK_ACK: rx = data; tp = (const struct tlv_parsed *) msgb_bcid(rx); /* If a BVC-BLOCK-ACK PDU is received by a BSS for the signalling BVC, the PDU is ignored. */ if (bfp->bvci == 0) { LOGPFSML(fi, LOGL_ERROR, "Rx BVC-BLOCK-ACK on BVCI=0 is illegal\n"); if (!bfp->role_sgsn) break; _tx_status(fi, BSSGP_CAUSE_SEM_INCORR_PDU, rx); break; } /* stop T1 timer */ osmo_fsm_inst_state_chg(fi, BSSGP_BVCFSM_S_BLOCKED, 0, 0); break; case BSSGP_BVCFSM_E_RX_BLOCK: rx = data; tp = (const struct tlv_parsed *) msgb_bcid(rx); cause = *TLVP_VAL(tp, BSSGP_IE_CAUSE); LOGPFSML(fi, LOGL_NOTICE, "Rx BVC-BLOCK (cause=%s)\n", bssgp_cause_str(cause)); /* If a BVC-BLOCK PDU is received by an SGSN for a blocked BVC, a BVC-BLOCK-ACK * PDU shall be returned. */ if (bfp->role_sgsn) { /* If a BVC-BLOCK PDU is received by an SGSN for * the signalling BVC, the PDU is ignored */ if (bfp->bvci == 0) break; tx = bssgp2_enc_bvc_block_ack(bfp->bvci); fi_tx_sig(fi, tx); } break; case BSSGP_BVCFSM_E_RX_UNBLOCK: rx = data; tp = (const struct tlv_parsed *) msgb_bcid(rx); LOGPFSML(fi, LOGL_NOTICE, "Rx BVC-UNBLOCK\n"); if (bfp->bvci == 0) { LOGPFSML(fi, LOGL_ERROR, "Rx BVC-UNBLOCK on BVCI=0 is illegal\n"); /* If BVC-UNBLOCK PDU is received by an SGSN for the signalling BVC, the PDU is ignored.*/ if (bfp->role_sgsn) break; _tx_status(fi, BSSGP_CAUSE_SEM_INCORR_PDU, rx); break; } if (!bfp->role_sgsn) { LOGPFSML(fi, LOGL_ERROR, "Rx BVC-UNBLOCK on BSS is illegal\n"); _tx_status(fi, BSSGP_CAUSE_SEM_INCORR_PDU, rx); break; } tx = bssgp2_enc_bvc_unblock_ack(bfp->bvci); fi_tx_sig(fi, tx); osmo_fsm_inst_state_chg(fi, BSSGP_BVCFSM_S_UNBLOCKED, T1_SECS, T1); break; case BSSGP_BVCFSM_E_REQ_UNBLOCK: if (bfp->role_sgsn) { LOGPFSML(fi, LOGL_ERROR, "SGSN side cannot initiate BVC unblock\n"); break; } if (bfp->bvci == 0) { LOGPFSML(fi, LOGL_ERROR, "BVCI 0 cannot be unblocked\n"); break; } bfp->locally_blocked = false; tx = bssgp2_enc_bvc_unblock(bfp->bvci); fi_tx_sig(fi, tx); osmo_fsm_inst_state_chg(fi, BSSGP_BVCFSM_S_UNBLOCKED, 0, 0); break; } } /* Waiting for RESET-ACK: Receive PDUs but don't transmit */ static void bssgp_bvc_fsm_wait_reset_ack(struct osmo_fsm_inst *fi, uint32_t event, void *data) { struct bvc_fsm_priv *bfp = fi->priv; const struct tlv_parsed *tp = NULL; struct msgb *rx = NULL, *tx; uint8_t cause; switch (event) { case BSSGP_BVCFSM_E_RX_RESET: /* 48.018 Section 8.4.3: If the BSS (or SGSN) has sent a BVC-RESET PDU for a BVCI to * the SGSN (or BSS) and is awaiting a BVC-RESET-ACK PDU in response, but instead * receives a BVC-RESET PDU indicating the same BVCI, then this shall be interpreted * as a BVC-RESET ACK PDU and the T2 timer shall be stopped. */ /* fall-through */ case BSSGP_BVCFSM_E_RX_RESET_ACK: rx = data; cause = bfp->last_reset_cause; tp = (const struct tlv_parsed *) msgb_bcid(rx); if (bfp->bvci == 0) update_negotiated_features(fi, tp); if (bfp->role_sgsn && bfp->bvci != 0) bfp->cell_id = bssgp_parse_cell_id(&bfp->ra_id, TLVP_VAL(tp, BSSGP_IE_CELL_ID)); if (!bfp->role_sgsn && bfp->bvci != 0 && bfp->locally_blocked) { /* initiate the blocking procedure */ /* transmit BVC-BLOCK, transition to BLOCKED state and start re-transmit timer */ tx = bssgp2_enc_bvc_block(bfp->bvci, bfp->block_cause); fi_tx_sig(fi, tx); osmo_fsm_inst_state_chg(fi, BSSGP_BVCFSM_S_BLOCKED, T1_SECS, T1); } else osmo_fsm_inst_state_chg(fi, BSSGP_BVCFSM_S_UNBLOCKED, 0, 0); if (bfp->ops && bfp->ops->reset_ack_notification) bfp->ops->reset_ack_notification(bfp->nsei, bfp->bvci, &bfp->ra_id, bfp->cell_id, cause, bfp->ops_priv); break; } } static void bssgp_bvc_fsm_unblocked(struct osmo_fsm_inst *fi, uint32_t event, void *data) { struct bssgp2_flow_ctrl rx_fc, *tx_fc; struct bvc_fsm_priv *bfp = fi->priv; const struct tlv_parsed *tp = NULL; struct msgb *rx = NULL, *tx; int rc; switch (event) { case BSSGP_BVCFSM_E_RX_UNBLOCK_ACK: rx = data; tp = (const struct tlv_parsed *) msgb_bcid(rx); /* If BVC-UNBLOCK-ACK PDU is received by an BSS for the signalling BVC, the PDU is ignored. */ if (bfp->bvci == 0) { LOGPFSML(fi, LOGL_ERROR, "Rx BVC-UNBLOCK-ACK on BVCI=0 is illegal\n"); if (!bfp->role_sgsn) break; _tx_status(fi, BSSGP_CAUSE_SEM_INCORR_PDU, rx); break; } /* stop T1 timer */ osmo_fsm_inst_state_chg(fi, BSSGP_BVCFSM_S_UNBLOCKED, 0, 0); break; case BSSGP_BVCFSM_E_RX_UNBLOCK: rx = data; tp = (const struct tlv_parsed *) msgb_bcid(rx); /* If a BVC-UNBLOCK PDU is received by an SGSN for a blocked BVC, a BVC-UNBLOCK-ACK * PDU shall be returned. */ if (bfp->role_sgsn) { /* If a BVC-UNBLOCK PDU is received by an SGSN for * the signalling BVC, the PDU is ignored */ if (bfp->bvci == 0) break; bssgp_tx_simple_bvci(BSSGP_PDUT_BVC_UNBLOCK_ACK, bfp->nsei, bfp->bvci, 0); } break; case BSSGP_BVCFSM_E_RX_BLOCK: rx = data; tp = (const struct tlv_parsed *) msgb_bcid(rx); LOGPFSML(fi, LOGL_NOTICE, "Rx BVC-BLOCK (cause=%s)\n", bssgp_cause_str(*TLVP_VAL(tp, BSSGP_IE_CAUSE))); /* If a BVC-BLOCK PDU is received by an SGSN for the signalling BVC, the PDU is ignored */ if (bfp->bvci == 0) { LOGPFSML(fi, LOGL_ERROR, "Rx BVC-BLOCK on BVCI=0 is illegal\n"); if (bfp->role_sgsn) break; _tx_status(fi, BSSGP_CAUSE_SEM_INCORR_PDU, rx); break; } if (!bfp->role_sgsn) { LOGPFSML(fi, LOGL_ERROR, "Rx BVC-BLOCK on BSS is illegal\n"); _tx_status(fi, BSSGP_CAUSE_SEM_INCORR_PDU, rx); break; } /* transmit BVC-BLOCK-ACK, transition to BLOCKED state */ tx = bssgp2_enc_bvc_block_ack(bfp->bvci); fi_tx_sig(fi, tx); osmo_fsm_inst_state_chg(fi, BSSGP_BVCFSM_S_BLOCKED, 0, 0); break; case BSSGP_BVCFSM_E_REQ_BLOCK: if (bfp->role_sgsn) { LOGPFSML(fi, LOGL_ERROR, "SGSN may not initiate BVC-BLOCK\n"); break; } if (bfp->bvci == 0) { LOGPFSML(fi, LOGL_ERROR, "BVCI 0 cannot be blocked\n"); break; } bfp->locally_blocked = true; bfp->block_cause = *(uint8_t *)data; /* transmit BVC-BLOCK, transition to BLOCKED state and start re-transmit timer */ tx = bssgp2_enc_bvc_block(bfp->bvci, bfp->block_cause); fi_tx_sig(fi, tx); osmo_fsm_inst_state_chg(fi, BSSGP_BVCFSM_S_BLOCKED, T1_SECS, T1); break; case BSSGP_BVCFSM_E_RX_FC_BVC: rx = data; tp = (const struct tlv_parsed *) msgb_bcid(rx); /* we assume osmo_tlv_prot_* has been used before calling here to ensure this */ OSMO_ASSERT(bfp->role_sgsn); rc = bssgp2_dec_fc_bvc(&rx_fc, tp); if (rc < 0) { _tx_status(fi, BSSGP_CAUSE_SEM_INCORR_PDU, rx); break; } if (bfp->ops->rx_fc_bvc) bfp->ops->rx_fc_bvc(bfp->nsei, bfp->bvci, &rx_fc, bfp->ops_priv); tx = bssgp2_enc_fc_bvc_ack(rx_fc.tag); fi_tx_ptp(fi, tx); break; case BSSGP_BVCFSM_E_RX_FC_BVC_ACK: rx = data; tp = (const struct tlv_parsed *) msgb_bcid(rx); /* we assume osmo_tlv_prot_* has been used before calling here to ensure this */ OSMO_ASSERT(!bfp->role_sgsn); break; case BSSGP_BVCFSM_E_REQ_FC_BVC: tx_fc = data; tx = bssgp2_enc_fc_bvc(tx_fc, bfp->features.negotiated & (BSSGP_XFEAT_GBIT << 8) ? &bfp->features.fc_granularity : NULL); fi_tx_ptp(fi, tx); break; } } static void bssgp_bvc_fsm_allstate(struct osmo_fsm_inst *fi, uint32_t event, void *data) { struct bvc_fsm_priv *bfp = fi->priv; uint8_t cause; const struct tlv_parsed *tp = NULL; struct msgb *rx = NULL; switch (event) { case BSSGP_BVCFSM_E_REQ_RESET: bfp->locally_blocked = false; cause = bfp->last_reset_cause = *(uint8_t *) data; _tx_bvc_reset(fi, cause); osmo_fsm_inst_state_chg(fi, BSSGP_BVCFSM_S_WAIT_RESET_ACK, T2_SECS, T2); #if 0 /* not sure if we really should notify the application if itself has requested the reset? */ if (bfp->ops && bfp->ops->reset_notification) bfp->ops->reset_notification(bfp->nsei, bfp->bvci, NULL, 0, cause, bfp->ops_priv); #endif break; case BSSGP_BVCFSM_E_RX_RESET: rx = data; tp = (const struct tlv_parsed *) msgb_bcid(rx); cause = *TLVP_VAL(tp, BSSGP_IE_CAUSE); if (bfp->role_sgsn && bfp->bvci != 0) bfp->cell_id = bssgp_parse_cell_id(&bfp->ra_id, TLVP_VAL(tp, BSSGP_IE_CELL_ID)); LOGPFSML(fi, LOGL_NOTICE, "Rx BVC-RESET (cause=%s)\n", bssgp_cause_str(cause)); if (bfp->bvci == 0) update_negotiated_features(fi, tp); _tx_bvc_reset_ack(fi); osmo_fsm_inst_state_chg(fi, BSSGP_BVCFSM_S_UNBLOCKED, 0, 0); if (bfp->ops && bfp->ops->reset_notification) { bfp->ops->reset_notification(bfp->nsei, bfp->bvci, &bfp->ra_id, bfp->cell_id, cause, bfp->ops_priv); } break; } } static int bssgp_bvc_fsm_timer_cb(struct osmo_fsm_inst *fi) { struct bvc_fsm_priv *bfp = fi->priv; struct msgb *tx; switch (fi->T) { case T1: switch (fi->state) { case BSSGP_BVCFSM_S_BLOCKED: /* re-transmit BVC-BLOCK */ tx = bssgp2_enc_bvc_block(bfp->bvci, bfp->block_cause); fi_tx_sig(fi, tx); osmo_fsm_inst_state_chg(fi, BSSGP_BVCFSM_S_BLOCKED, T1_SECS, T1); break; case BSSGP_BVCFSM_S_UNBLOCKED: /* re-transmit BVC-UNBLOCK */ tx = bssgp2_enc_bvc_unblock(bfp->bvci); fi_tx_sig(fi, tx); osmo_fsm_inst_state_chg(fi, BSSGP_BVCFSM_S_UNBLOCKED, T1_SECS, T1); break; } break; case T2: switch (fi->state) { case BSSGP_BVCFSM_S_WAIT_RESET_ACK: /* re-transmit BVC-RESET */ _tx_bvc_reset(fi, bfp->last_reset_cause); osmo_fsm_inst_state_chg(fi, BSSGP_BVCFSM_S_WAIT_RESET_ACK, T2_SECS, T2); break; case BSSGP_BVCFSM_S_UNBLOCKED: /* re-transmit BVC-RESET-ACK */ _tx_bvc_reset_ack(fi); osmo_fsm_inst_state_chg(fi, BSSGP_BVCFSM_S_UNBLOCKED, T2_SECS, T2); break; } break; default: OSMO_ASSERT(0); break; } return 0; } static const struct osmo_fsm_state bssgp_bvc_fsm_states[] = { [BSSGP_BVCFSM_S_NULL] = { /* initial state from which we must do a RESET */ .name = "NULL", .in_event_mask = 0, .out_state_mask = S(BSSGP_BVCFSM_S_WAIT_RESET_ACK) | S(BSSGP_BVCFSM_S_UNBLOCKED), .action = bssgp_bvc_fsm_null, }, [BSSGP_BVCFSM_S_BLOCKED] = { .name = "BLOCKED", .in_event_mask = S(BSSGP_BVCFSM_E_RX_UNBLOCK) | S(BSSGP_BVCFSM_E_RX_BLOCK) | S(BSSGP_BVCFSM_E_RX_BLOCK_ACK) | S(BSSGP_BVCFSM_E_REQ_UNBLOCK), .out_state_mask = S(BSSGP_BVCFSM_S_WAIT_RESET_ACK) | S(BSSGP_BVCFSM_S_UNBLOCKED) | S(BSSGP_BVCFSM_S_BLOCKED), .action = bssgp_bvc_fsm_blocked, .onenter = bssgp_bvc_fsm_blocked_onenter, }, [BSSGP_BVCFSM_S_WAIT_RESET_ACK]= { .name = "WAIT_RESET_ACK", .in_event_mask = S(BSSGP_BVCFSM_E_RX_RESET_ACK) | S(BSSGP_BVCFSM_E_RX_RESET), .out_state_mask = S(BSSGP_BVCFSM_S_UNBLOCKED) | S(BSSGP_BVCFSM_S_BLOCKED) | S(BSSGP_BVCFSM_S_WAIT_RESET_ACK), .action = bssgp_bvc_fsm_wait_reset_ack, .onenter = _onenter_tail, }, [BSSGP_BVCFSM_S_UNBLOCKED] = { .name = "UNBLOCKED", .in_event_mask = S(BSSGP_BVCFSM_E_RX_BLOCK) | S(BSSGP_BVCFSM_E_RX_UNBLOCK) | S(BSSGP_BVCFSM_E_RX_UNBLOCK_ACK) | S(BSSGP_BVCFSM_E_REQ_BLOCK) | S(BSSGP_BVCFSM_E_RX_FC_BVC) | S(BSSGP_BVCFSM_E_RX_FC_BVC_ACK) | S(BSSGP_BVCFSM_E_REQ_FC_BVC), .out_state_mask = S(BSSGP_BVCFSM_S_BLOCKED) | S(BSSGP_BVCFSM_S_WAIT_RESET_ACK) | S(BSSGP_BVCFSM_S_UNBLOCKED), .action = bssgp_bvc_fsm_unblocked, .onenter = _onenter_tail, }, }; static struct osmo_fsm bssgp_bvc_fsm = { .name = "BSSGP-BVC", .states = bssgp_bvc_fsm_states, .num_states = ARRAY_SIZE(bssgp_bvc_fsm_states), .allstate_event_mask = S(BSSGP_BVCFSM_E_REQ_RESET) | S(BSSGP_BVCFSM_E_RX_RESET), .allstate_action = bssgp_bvc_fsm_allstate, .timer_cb = bssgp_bvc_fsm_timer_cb, .log_subsys = DLBSSGP, .event_names = ptp_bvc_event_names, }; static struct osmo_fsm_inst * _bvc_fsm_alloc(void *ctx, struct gprs_ns2_inst *nsi, bool role_sgsn, uint16_t nsei, uint16_t bvci) { struct osmo_fsm_inst *fi; struct bvc_fsm_priv *bfp; char idbuf[64]; /* TODO: encode our role in the id string? */ snprintf(idbuf, sizeof(idbuf), "NSE%05u-BVC%05u", nsei, bvci); fi = osmo_fsm_inst_alloc(&bssgp_bvc_fsm, ctx, NULL, LOGL_INFO, idbuf); if (!fi) return NULL; bfp = talloc_zero(fi, struct bvc_fsm_priv); if (!bfp) { osmo_fsm_inst_free(fi); return NULL; } fi->priv = bfp; bfp->nsi = nsi; bfp->role_sgsn = role_sgsn; bfp->nsei = nsei; bfp->bvci = bvci; bfp->max_pdu_len = UINT16_MAX; return fi; } /*! Allocate a SIGNALING-BVC FSM for the BSS role (facing a remote SGSN). * \param[in] ctx talloc context from which to allocate * \param[in] nsi NS Instance on which this BVC operates * \param[in] nsei NS Entity Identifier on which this BVC operates * \param[in] features Feature [byte 0] and Extended Feature [byte 1] bitmap * \returns newly-allocated FSM Instance; NULL in case of error */ struct osmo_fsm_inst * bssgp_bvc_fsm_alloc_sig_bss(void *ctx, struct gprs_ns2_inst *nsi, uint16_t nsei, uint32_t features) { struct osmo_fsm_inst *fi = _bvc_fsm_alloc(ctx, nsi, false, nsei, 0); struct bvc_fsm_priv *bfp; if (!fi) return NULL; bfp = fi->priv; bfp->features.advertised = features; return fi; } /*! Allocate a PTP-BVC FSM for the BSS role (facing a remote SGSN). * \param[in] ctx talloc context from which to allocate * \param[in] nsi NS Instance on which this BVC operates * \param[in] nsei NS Entity Identifier on which this BVC operates * \param[in] bvci BVCI of this FSM * \param[in] ra_id Routing Area Identity of the cell (reported to SGSN) * \param[in] cell_id Cell Identifier of the cell (reported to SGSN) * \returns newly-allocated FSM Instance; NULL in case of error */ struct osmo_fsm_inst * bssgp_bvc_fsm_alloc_ptp_bss(void *ctx, struct gprs_ns2_inst *nsi, uint16_t nsei, uint16_t bvci, const struct gprs_ra_id *ra_id, uint16_t cell_id) { struct osmo_fsm_inst *fi; struct bvc_fsm_priv *bfp; OSMO_ASSERT(bvci >= 2); OSMO_ASSERT(ra_id); fi = _bvc_fsm_alloc(ctx, nsi, false, nsei, bvci); if (!fi) return NULL; bfp = fi->priv; bfp->ra_id = *ra_id; bfp->cell_id = cell_id; return fi; } /*! Allocate a SIGNALING-BVC FSM for the SGSN role (facing a remote BSS). * \param[in] ctx talloc context from which to allocate * \param[in] nsi NS Instance on which this BVC operates * \param[in] nsei NS Entity Identifier on which this BVC operates * \param[in] features Feature [byte 0] and Extended Feature [byte 1] bitmap * \returns newly-allocated FSM Instance; NULL in case of error */ struct osmo_fsm_inst * bssgp_bvc_fsm_alloc_sig_sgsn(void *ctx, struct gprs_ns2_inst *nsi, uint16_t nsei, uint32_t features) { struct osmo_fsm_inst *fi = _bvc_fsm_alloc(ctx, nsi, true, nsei, 0); struct bvc_fsm_priv *bfp; if (!fi) return NULL; bfp = fi->priv; bfp->features.advertised = features; return fi; } /*! Allocate a PTP-BVC FSM for the SGSN role (facing a remote BSS). * \param[in] ctx talloc context from which to allocate * \param[in] nsi NS Instance on which this BVC operates * \param[in] nsei NS Entity Identifier on which this BVC operates * \param[in] bvci BVCI of this FSM * \returns newly-allocated FSM Instance; NULL in case of error */ struct osmo_fsm_inst * bssgp_bvc_fsm_alloc_ptp_sgsn(void *ctx, struct gprs_ns2_inst *nsi, uint16_t nsei, uint16_t bvci) { struct osmo_fsm_inst *fi; OSMO_ASSERT(bvci >= 2); fi = _bvc_fsm_alloc(ctx, nsi, true, nsei, bvci); if (!fi) return NULL; return fi; } /*! Set the 'operations' callbacks + private data. * \param[in] fi FSM instance for which the data shall be set * \param[in] ops BSSGP BVC FSM operations (call-back functions) to register * \param[in] ops_priv opaque/private data pointer passed through to call-backs */ void bssgp_bvc_fsm_set_ops(struct osmo_fsm_inst *fi, const struct bssgp_bvc_fsm_ops *ops, void *ops_priv) { struct bvc_fsm_priv *bfp = fi->priv; OSMO_ASSERT(fi->fsm == &bssgp_bvc_fsm); bfp->ops = ops; bfp->ops_priv = ops_priv; } /*! Return if the given BVC FSM is in UNBLOCKED state. */ bool bssgp_bvc_fsm_is_unblocked(struct osmo_fsm_inst *fi) { return fi->state == BSSGP_BVCFSM_S_UNBLOCKED; } /*! Determine the cause value why given BVC FSM is blocked. */ uint8_t bssgp_bvc_fsm_get_block_cause(struct osmo_fsm_inst *fi) { struct bvc_fsm_priv *bfp = fi->priv; OSMO_ASSERT(fi->fsm == &bssgp_bvc_fsm); return bfp->block_cause; } /*! Return the advertised features / extended features. */ uint32_t bssgp_bvc_fsm_get_features_advertised(struct osmo_fsm_inst *fi) { struct bvc_fsm_priv *bfp = fi->priv; OSMO_ASSERT(fi->fsm == &bssgp_bvc_fsm); return bfp->features.advertised; } /*! Return the received features / extended features. */ uint32_t bssgp_bvc_fsm_get_features_received(struct osmo_fsm_inst *fi) { struct bvc_fsm_priv *bfp = fi->priv; OSMO_ASSERT(fi->fsm == &bssgp_bvc_fsm); return bfp->features.received; } /*! Return the negotiated features / extended features. */ uint32_t bssgp_bvc_fsm_get_features_negotiated(struct osmo_fsm_inst *fi) { struct bvc_fsm_priv *bfp = fi->priv; OSMO_ASSERT(fi->fsm == &bssgp_bvc_fsm); return bfp->features.negotiated; } /*! Set the maximum size of a BSSGP PDU. *! On the NS layer this corresponds to the size of an NS SDU in NS-UNITDATA (3GPP TS 48.016 Ch. 9.2.10) */ void bssgp_bvc_fsm_set_max_pdu_len(struct osmo_fsm_inst *fi, uint16_t max_pdu_len) { struct bvc_fsm_priv *bfp = fi->priv; OSMO_ASSERT(fi->fsm == &bssgp_bvc_fsm); bfp->max_pdu_len = max_pdu_len; } /*! Return the maximum size of a BSSGP PDU *! On the NS layer this corresponds to the size of an NS SDU in NS-UNITDATA (3GPP TS 48.016 Ch. 9.2.10) */ uint16_t bssgp_bvc_fsm_get_max_pdu_len(const struct osmo_fsm_inst *fi) { const struct bvc_fsm_priv *bfp = fi->priv; OSMO_ASSERT(fi->fsm == &bssgp_bvc_fsm); return bfp->max_pdu_len; } static __attribute__((constructor)) void on_dso_load_bvc_fsm(void) { OSMO_ASSERT(osmo_fsm_register(&bssgp_bvc_fsm) == 0); }