| /* BSSGP per-BVC Finite State Machine */ |
| |
| /* (C) 2020 Harald Welte <laforge@gnumonks.org> |
| * |
| * 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 <http://www.gnu.org/licenses/>. |
| * |
| */ |
| |
| #include <string.h> |
| #include <stdio.h> |
| |
| #include <osmocom/core/fsm.h> |
| #include <osmocom/core/logging.h> |
| #include <osmocom/core/utils.h> |
| #include <osmocom/core/tdef.h> |
| |
| #include <osmocom/gsm/gsm48.h> |
| #include <osmocom/gsm/tlv.h> |
| |
| #include <osmocom/gprs/gprs_msgb.h> |
| #include <osmocom/gprs/gprs_bssgp.h> |
| #include <osmocom/gprs/gprs_bssgp2.h> |
| #include <osmocom/gprs/bssgp_bvc_fsm.h> |
| |
| #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); |
| } |