diff options
Diffstat (limited to 'src/gsm/iuup.c')
| -rw-r--r-- | src/gsm/iuup.c | 1064 |
1 files changed, 1064 insertions, 0 deletions
diff --git a/src/gsm/iuup.c b/src/gsm/iuup.c new file mode 100644 index 00000000..16a6f5e0 --- /dev/null +++ b/src/gsm/iuup.c @@ -0,0 +1,1064 @@ +/*! \file iu_up.c + * IuUP (Iu User Plane) according to 3GPP TS 25.415 */ +/* + * (C) 2017 by Harald Welte <laforge@gnumonks.org> + * + * 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. + */ + +#include <errno.h> +#include <inttypes.h> + +#include <osmocom/core/crc8gen.h> +#include <osmocom/core/crc16gen.h> +#include <osmocom/core/fsm.h> +#include <osmocom/core/prim.h> +#include <osmocom/core/timer.h> +#include <osmocom/core/logging.h> + +#include <osmocom/gsm/prim.h> +#include <osmocom/gsm/protocol/gsm_25_415.h> +#include <osmocom/gsm/iuup.h> + +/*********************************************************************** + * CRC Calculation + ***********************************************************************/ + +/* Section 6.6.3.8 Header CRC */ +const struct osmo_crc8gen_code iuup_hdr_crc_code = { + .bits = 6, + .poly = 47, + .init = 0, + .remainder = 0, +}; + +/* Section 6.6.3.9 Payload CRC */ +const struct osmo_crc16gen_code iuup_data_crc_code = { + .bits = 10, + .poly = 563, + .init = 0, + .remainder = 0, +}; + +static int iuup_get_payload_offset(const uint8_t *iuup_pdu) +{ + uint8_t pdu_type = iuup_pdu[0] >> 4; + switch (pdu_type) { + case 0: + case 14: + return 4; + case 1: + return 3; + default: + return -1; + } +} + +int osmo_iuup_compute_payload_crc(const uint8_t *iuup_pdu, unsigned int pdu_len) +{ + ubit_t buf[1024*8]; + uint8_t pdu_type; + int offset, payload_len_bytes; + + if (pdu_len < 1) + return -1; + + pdu_type = iuup_pdu[0] >> 4; + + /* Type 1 has no CRC */ + if (pdu_type == 1) + return 0; + + offset = iuup_get_payload_offset(iuup_pdu); + if (offset < 0) + return offset; + + if (pdu_len < offset) + return -1; + + payload_len_bytes = pdu_len - offset; + osmo_pbit2ubit(buf, iuup_pdu+offset, payload_len_bytes*8); + return osmo_crc16gen_compute_bits(&iuup_data_crc_code, buf, payload_len_bytes*8); +} + +int osmo_iuup_compute_header_crc(const uint8_t *iuup_pdu, unsigned int pdu_len) +{ + ubit_t buf[2*8]; + + if (pdu_len < 2) + return -1; + + osmo_pbit2ubit(buf, iuup_pdu, 2*8); + return osmo_crc8gen_compute_bits(&iuup_hdr_crc_code, buf, 2*8); +} + +/*********************************************************************** + * Internal State / FSM (Annex B) + ***********************************************************************/ + +#define S(x) (1 << (x)) + +#define IUUP_TIMER_INIT 1 +#define IUUP_TIMER_TA 2 +#define IUUP_TIMER_RC 3 + +struct osmo_timer_nt { + uint32_t n; /* number of repetitions */ + struct osmo_iuup_tnl_prim *retrans_itp; + struct osmo_timer_list timer; +}; + +struct osmo_iuup_instance { + struct osmo_iuup_rnl_config config; + struct osmo_fsm_inst *fi; + + uint8_t mode_version; + + struct { + struct osmo_timer_nt init; + struct osmo_timer_nt ta; + struct osmo_timer_nt rc; + } timer; + /* call-back function to pass primitives up to the user */ + osmo_prim_cb user_prim_cb; + void *user_prim_priv; + osmo_prim_cb transport_prim_cb; + void *transport_prim_priv; + uint8_t type14_fn; /* 2 bits */ +}; + +enum iuup_fsm_state { + IUUP_FSM_ST_NULL, + IUUP_FSM_ST_INIT, + IUUP_FSM_ST_TrM_DATA_XFER_READY, + IUUP_FSM_ST_SMpSDU_DATA_XFER_READY, +}; + +enum iuup_fsm_event { + IUUP_FSM_EVT_IUUP_CONFIG_REQ, + IUUP_FSM_EVT_IUUP_DATA_REQ, + IUUP_FSM_EVT_IUUP_DATA_IND, + IUUP_FSM_EVT_IUUP_STATUS_REQ, + IUUP_FSM_EVT_IUUP_STATUS_IND, + IUUP_FSM_EVT_SSASAR_UNITDATA_REQ, + IUUP_FSM_EVT_SSASAR_UNITDATA_IND, + IUUP_FSM_EVT_IUUP_UNITDATA_REQ, + IUUP_FSM_EVT_IUUP_UNITDATA_IND, + IUUP_FSM_EVT_INIT, + IUUP_FSM_EVT_LAST_INIT_ACK, + IUUP_FSM_EVT_INIT_NACK, +}; + +static const struct value_string iuup_fsm_event_names[] = { + { IUUP_FSM_EVT_IUUP_CONFIG_REQ, "IuUP-CONFIG-req" }, + { IUUP_FSM_EVT_IUUP_DATA_REQ, "IuUP-DATA-req" }, + { IUUP_FSM_EVT_IUUP_DATA_IND, "IuUP-DATA-ind" }, + { IUUP_FSM_EVT_IUUP_STATUS_REQ, "IuUP-STATUS-req" }, + { IUUP_FSM_EVT_IUUP_STATUS_IND, "IuUP-STATUS-ind" }, + { IUUP_FSM_EVT_SSASAR_UNITDATA_REQ, "SSSAR-UNITDATA-req" }, + { IUUP_FSM_EVT_SSASAR_UNITDATA_IND, "SSSAR-UNITDATA-ind" }, + { IUUP_FSM_EVT_IUUP_UNITDATA_REQ, "IuUP-UNITDATA-req" }, + { IUUP_FSM_EVT_IUUP_UNITDATA_IND, "IuUP-UNITDATA-ind" }, + { IUUP_FSM_EVT_INIT, "INIT" }, + { IUUP_FSM_EVT_LAST_INIT_ACK, "LAST_INIT_ACK" }, + { IUUP_FSM_EVT_INIT_NACK, "INIT_NACK" }, + { 0, NULL } +}; + +static inline uint8_t iuup_get_pdu_type(const uint8_t *data) +{ + return data[0] >> 4; +} + +static inline uint8_t iuup_get_hdr_crc(const uint8_t *data) +{ + return data[2] >> 2; +} + +/* Helper functions to store non-packed structs in msgb so that pointers are properly aligned: */ +#define IUUP_MSGB_SIZE 4096 +#define PTR_ALIGNMENT_BYTES 8 +#define IUUP_MSGB_HEADROOM_MIN_REQUIRED (OSMO_MAX(sizeof(struct osmo_iuup_tnl_prim), sizeof(struct osmo_iuup_rnl_prim)) + (PTR_ALIGNMENT_BYTES - 1)) +static inline struct msgb *osmo_iuup_msgb_alloc_c(void *ctx, size_t size) +{ + OSMO_ASSERT(size > IUUP_MSGB_HEADROOM_MIN_REQUIRED); + return msgb_alloc_headroom_c(ctx, size, IUUP_MSGB_HEADROOM_MIN_REQUIRED, "iuup-msgb"); +} + +/* push data so that the resulting pointer to write to is aligned to 8 byte */ +static inline __attribute__((assume_aligned(PTR_ALIGNMENT_BYTES))) +unsigned char *aligned_msgb_push(struct msgb *msg, unsigned int len) +{ + uint8_t *ptr = (msgb_data(msg) - len); + size_t extra_size = ((uintptr_t)ptr & (PTR_ALIGNMENT_BYTES - 1)); + + return msgb_push(msg, len + extra_size); +} + +struct osmo_iuup_rnl_prim *osmo_iuup_rnl_prim_alloc(void *ctx, unsigned int primitive, unsigned int operation, unsigned int size) +{ + struct msgb *msg; + struct osmo_iuup_rnl_prim *irp; + + msg = osmo_iuup_msgb_alloc_c(ctx, size); + irp = (struct osmo_iuup_rnl_prim *)aligned_msgb_push(msg, sizeof(*irp)); + osmo_prim_init(&irp->oph, SAP_IUUP_RNL, primitive, operation, msg); + return irp; +} + +struct osmo_iuup_tnl_prim *osmo_iuup_tnl_prim_alloc(void *ctx, unsigned int primitive, unsigned int operation, unsigned int size) +{ + struct msgb *msg; + struct osmo_iuup_tnl_prim *itp; + + msg = osmo_iuup_msgb_alloc_c(ctx, size); + itp = (struct osmo_iuup_tnl_prim *) aligned_msgb_push(msg, sizeof(*itp)); + osmo_prim_init(&itp->oph, SAP_IUUP_TNL, primitive, operation, msg); + return itp; +} + +/* 6.6.2.3.2 */ +static struct osmo_iuup_tnl_prim *itp_ctrl_ack_alloc(struct osmo_iuup_instance *iui, enum iuup_procedure proc_ind, uint8_t fn) +{ + struct osmo_iuup_tnl_prim *itp; + struct iuup_ctrl_ack *ack; + itp = osmo_iuup_tnl_prim_alloc(iui, OSMO_IUUP_TNL_UNITDATA, PRIM_OP_REQUEST, IUUP_MSGB_SIZE); + itp->oph.msg->l2h = msgb_put(itp->oph.msg, sizeof(struct iuup_ctrl_ack)); + ack = (struct iuup_ctrl_ack *) msgb_l2(itp->oph.msg); + *ack = (struct iuup_ctrl_ack){ + .hdr = { + .frame_nr = fn, + .ack_nack = IUUP_AN_ACK, + .pdu_type = IUUP_PDU_T_CONTROL, + .proc_ind = proc_ind, + .mode_version = iui->mode_version, + .payload_crc_hi = 0, + .header_crc = 0, + .payload_crc_lo = 0, + }, + }; + ack->hdr.header_crc = osmo_iuup_compute_header_crc(msgb_l2(itp->oph.msg), msgb_l2len(itp->oph.msg)); + return itp; +} + +/* 6.6.2.3.3 */ +static struct osmo_iuup_tnl_prim *tnp_ctrl_nack_alloc(struct osmo_iuup_instance *iui, enum iuup_procedure proc_ind, enum iuup_error_cause error_cause, uint8_t fn) +{ + struct osmo_iuup_tnl_prim *itp; + struct iuup_ctrl_nack *nack; + itp = osmo_iuup_tnl_prim_alloc(iui, OSMO_IUUP_TNL_UNITDATA, PRIM_OP_REQUEST, IUUP_MSGB_SIZE); + itp->oph.msg->l2h = msgb_put(itp->oph.msg, sizeof(struct iuup_ctrl_nack)); + nack = (struct iuup_ctrl_nack *) msgb_l2(itp->oph.msg); + *nack = (struct iuup_ctrl_nack){ + .hdr = { + .frame_nr = fn, + .ack_nack = IUUP_AN_NACK, + .pdu_type = IUUP_PDU_T_CONTROL, + .proc_ind = proc_ind, + .mode_version = iui->mode_version, + .payload_crc_hi = 0, + .header_crc = 0, + .payload_crc_lo = 0, + }, + .spare = 0, + .error_cause = error_cause, + }; + nack->hdr.header_crc = osmo_iuup_compute_header_crc(msgb_l2(itp->oph.msg), msgb_l2len(itp->oph.msg)); + return itp; +} + +/* 6.6.2.3.4.1 */ +static struct osmo_iuup_tnl_prim *tnp_ctrl_init_alloc(struct osmo_iuup_instance *iui) +{ + struct osmo_iuup_tnl_prim *itp; + struct iuup_pdutype14_hdr *hdr; + struct iuup_ctrl_init_hdr *ihdr; + struct iuup_ctrl_init_rfci_hdr *ihdr_rfci; + struct iuup_ctrl_init_tail *itail; + unsigned int i, j; + uint16_t payload_crc; + uint8_t rfci_cnt; + struct msgb *msg; + + itp = osmo_iuup_tnl_prim_alloc(iui, OSMO_IUUP_TNL_UNITDATA, PRIM_OP_REQUEST, IUUP_MSGB_SIZE); + msg = itp->oph.msg; + + msg->l2h = msgb_put(msg, sizeof(*hdr)); + hdr = (struct iuup_pdutype14_hdr *)msgb_l2(msg); + hdr->frame_nr = iui->type14_fn++; + hdr->ack_nack = IUUP_AN_PROCEDURE; + hdr->pdu_type = IUUP_PDU_T_CONTROL; + hdr->proc_ind = IUUP_PROC_INIT; + hdr->mode_version = 0; /* Use here the minimum version required to negotiate */ + hdr->header_crc = osmo_iuup_compute_header_crc(msgb_l2(msg), msgb_l2len(msg)); + + ihdr = (struct iuup_ctrl_init_hdr *)msgb_put(msg, sizeof(*ihdr)); + ihdr->chain_ind = 0; /* this frame is the last frame for the procedure. TODO: support several */ + ihdr->num_subflows_per_rfci = iui->config.num_subflows; + ihdr->ti = iui->config.IPTIs_present ? 1 : 0; + ihdr->spare = 0; + + /* RFCI + subflow size part: */ + rfci_cnt = 0; + for (i = 0; i < ARRAY_SIZE(iui->config.rfci); i++) { + bool last; + uint8_t len_size; + struct osmo_iuup_rfci *rfci = &iui->config.rfci[i]; + if (!rfci->used) + continue; + rfci_cnt++; + last = (rfci_cnt == iui->config.num_rfci); + + len_size = 1; + for (j = 0; j < iui->config.num_subflows; j++) { + if (rfci->subflow_sizes[j] > UINT8_MAX) + len_size = 2; + } + + ihdr_rfci = (struct iuup_ctrl_init_rfci_hdr *)msgb_put(msg, sizeof(*ihdr_rfci) + len_size * iui->config.num_subflows); + ihdr_rfci->rfci = rfci->id; + ihdr_rfci->li = len_size - 1; + ihdr_rfci->lri = last; + if (len_size == 2) { + uint16_t *buf = (uint16_t *)&ihdr_rfci->subflow_length[0]; + for (j = 0; j < iui->config.num_subflows; j++) + osmo_store16be(rfci->subflow_sizes[j], buf++); + } else { + for (j = 0; j < iui->config.num_subflows; j++) + ihdr_rfci->subflow_length[j] = rfci->subflow_sizes[j]; + } + /* early loop termination: */ + if (last) + break; + } + /* Sanity check: */ + if (rfci_cnt != iui->config.num_rfci) { + LOGP(DLIUUP, LOGL_ERROR, "rfci_cnt %u != num_rfci %u\n", + rfci_cnt, iui->config.num_rfci); + msgb_free(msg); + return NULL; + } + + if (iui->config.IPTIs_present) { + uint8_t num_bytes = (iui->config.num_rfci + 1) / 2; + uint8_t *buf = msgb_put(msg, num_bytes); + rfci_cnt = 0; + for (i = 0; i < ARRAY_SIZE(iui->config.rfci); i++) { + struct osmo_iuup_rfci *rfci = &iui->config.rfci[i]; + if (!rfci->used) + continue; + if (!(rfci_cnt & 0x01)) /* is even: */ + buf[rfci_cnt / 2] = (((uint8_t)rfci->IPTI) << 4); + else + buf[rfci_cnt / 2] |= (rfci->IPTI & 0x0F); + rfci_cnt++; + /* early loop termination: */ + if (rfci_cnt == iui->config.num_rfci) + break; + } + } + + itail = (struct iuup_ctrl_init_tail *)msgb_put(msg, sizeof(*itail)); + osmo_store16be(iui->config.supported_versions_mask, &itail->versions_supported); + itail->spare = 0; + itail->data_pdu_type = iui->config.data_pdu_type; + + payload_crc = osmo_iuup_compute_payload_crc(msgb_l2(msg), msgb_l2len(msg)); + hdr->payload_crc_hi = (payload_crc >> 8) & 0x03; + hdr->payload_crc_lo = payload_crc & 0xff; + + + return itp; +} + +static struct osmo_iuup_rnl_prim *irp_init_ind_alloc(struct osmo_iuup_instance *iui) +{ + struct osmo_iuup_rnl_prim *irp; + + irp = osmo_iuup_rnl_prim_alloc(iui, OSMO_IUUP_RNL_STATUS, PRIM_OP_INDICATION, IUUP_MSGB_SIZE); + irp->u.status.procedure = IUUP_PROC_INIT; + irp->u.status.u.initialization.mode_version = iui->mode_version; + irp->u.status.u.initialization.data_pdu_type = iui->config.data_pdu_type; + irp->u.status.u.initialization.num_subflows = iui->config.num_subflows; + irp->u.status.u.initialization.num_rfci = iui->config.num_rfci; + irp->u.status.u.initialization.IPTIs_present = iui->config.IPTIs_present; + memcpy(irp->u.status.u.initialization.rfci, iui->config.rfci, sizeof(iui->config.rfci)); + return irp; +} + +/* transform a RNL data primitive into a TNL data primitive (down the stack) */ +static struct osmo_iuup_tnl_prim *rnl_to_tnl_data(struct osmo_iuup_instance *iui, + struct osmo_iuup_rnl_prim *irp) +{ + struct osmo_iuup_tnl_prim *itp; + struct osmo_iuup_rnl_data dt; + struct msgb *msg; + uint16_t payload_crc; + struct iuup_pdutype0_hdr *h0; + struct iuup_pdutype1_hdr *h1; + + OSMO_ASSERT(OSMO_PRIM_HDR(&irp->oph) == OSMO_PRIM(OSMO_IUUP_RNL_DATA, PRIM_OP_REQUEST)); + + msg = irp->oph.msg; + dt = irp->u.data; + + /* pull up to the IuUP payload and push a new primitive header in front */ + msgb_pull_to_l3(msg); + + /* push the PDU TYPE 0 / 1 header in front of the payload */ + switch (iui->config.data_pdu_type) { + case 0: + msg->l2h = msgb_push(msg, sizeof(*h0)); + h0 = (struct iuup_pdutype0_hdr *)msg->l2h; + h0->frame_nr = dt.frame_nr; + h0->pdu_type = IUUP_PDU_T_DATA_CRC; + h0->rfci = dt.rfci; + h0->fqc = dt.fqc; + h0->header_crc = osmo_iuup_compute_header_crc(msgb_l2(msg), msgb_l2len(msg)); + payload_crc = osmo_iuup_compute_payload_crc(msgb_l2(msg), msgb_l2len(msg)); + h0->payload_crc_hi = (payload_crc >> 8) & 0x03; + h0->payload_crc_lo = payload_crc & 0xff; + break; + case 1: + msg->l2h = msgb_push(msg, sizeof(*h1)); + h1 = (struct iuup_pdutype1_hdr *)msg->l2h; + h1->frame_nr = dt.frame_nr; + h1->pdu_type = IUUP_PDU_T_DATA_NOCRC; + h1->rfci = dt.rfci; + h1->fqc = dt.fqc; + h1->header_crc = osmo_iuup_compute_header_crc(msgb_l2(msg), msgb_l2len(msg)); + h1->spare = 0; + break; + default: + OSMO_ASSERT(0); + } + + /* Avoid allocating irp out of 8byte-aligned address, Asan is not happy with it */ + itp = (struct osmo_iuup_tnl_prim *) aligned_msgb_push(msg, sizeof(*itp)); + osmo_prim_init(&itp->oph, SAP_IUUP_TNL, OSMO_IUUP_TNL_UNITDATA, PRIM_OP_REQUEST, msg); + + return itp; +} + +/* transform a TNL primitive into a RNL primitive (up the stack) */ +static struct osmo_iuup_rnl_prim *tnl_to_rnl_data(struct osmo_iuup_tnl_prim *itp) +{ + struct msgb *msg; + struct iuup_pdutype0_hdr *h0; + struct iuup_pdutype1_hdr *h1; + struct osmo_iuup_rnl_data dt; + struct osmo_iuup_rnl_prim *irp; + + msg = itp->oph.msg; + + OSMO_ASSERT(OSMO_PRIM_HDR(&itp->oph) == OSMO_PRIM(OSMO_IUUP_TNL_UNITDATA, PRIM_OP_INDICATION)); + + switch (iuup_get_pdu_type(msgb_l2(msg))) { + case IUUP_PDU_T_DATA_CRC: + h0 = (struct iuup_pdutype0_hdr *) msgb_l2(msg); + dt.rfci = h0->rfci; + dt.frame_nr = h0->frame_nr; + dt.fqc = h0->fqc; + break; + case IUUP_PDU_T_DATA_NOCRC: + h1 = (struct iuup_pdutype1_hdr *) msgb_l2(msg); + dt.rfci = h1->rfci; + dt.frame_nr = h1->frame_nr; + dt.fqc = h1->fqc; + break; + default: + OSMO_ASSERT(0); + } + + /* pull up to the IuUP payload and push a new primitive header in front */ + msgb_pull_to_l3(msg); + + /* Avoid allocating irp out of 8byte-aligned address, Asan is not happy with it */ + irp = (struct osmo_iuup_rnl_prim *) aligned_msgb_push(msg, sizeof(*irp)); + osmo_prim_init(&irp->oph, SAP_IUUP_RNL, OSMO_IUUP_RNL_DATA, PRIM_OP_INDICATION, msg); + irp->u.data = dt; + + return irp; +} + +static struct osmo_iuup_rnl_prim *irp_error_event_alloc_c(void *ctx, enum iuup_error_cause cause, enum iuup_error_distance distance) +{ + struct osmo_iuup_rnl_prim *irp; + struct msgb *msg; + msg = msgb_alloc_c(ctx, sizeof(*irp), "iuup-tx"); + irp = (struct osmo_iuup_rnl_prim *) msgb_put(msg, sizeof(*irp)); + osmo_prim_init(&irp->oph, SAP_IUUP_RNL, OSMO_IUUP_RNL_STATUS, PRIM_OP_INDICATION, msg); + irp->u.status.procedure = IUUP_PROC_ERR_EVENT; + irp->u.status.u.error_event.cause = cause; + irp->u.status.u.error_event.distance = distance; + return irp; +} + +static struct osmo_iuup_tnl_prim *itp_copy_c(void *ctx, const struct osmo_iuup_tnl_prim *src_itp) +{ + struct msgb *msg; + struct osmo_iuup_tnl_prim *dst_itp; + + msg = msgb_copy_c(ctx, src_itp->oph.msg, "iuup-tx-retrans"); + dst_itp = (struct osmo_iuup_tnl_prim *)msgb_data(msg); + dst_itp->oph.msg = msg; + return dst_itp; +} + +static void retransmit_initialization(struct osmo_iuup_instance *iui) +{ + struct osmo_iuup_tnl_prim *itp; + iui->fi->T = IUUP_TIMER_INIT; + osmo_timer_schedule(&iui->fi->timer, iui->config.t_init.t_ms / 1000, (iui->config.t_init.t_ms % 1000) * 1000); + itp = itp_copy_c(iui, iui->timer.init.retrans_itp); + iui->transport_prim_cb(&itp->oph, iui->transport_prim_priv); +} + +/* return: whether the last Init was Acked correctly and hence can transition to next state */ +static bool iuup_rx_initialization(struct osmo_iuup_instance *iui, struct osmo_iuup_tnl_prim *itp) +{ + struct iuup_pdutype14_hdr *hdr; + struct iuup_ctrl_init_hdr *ihdr; + struct iuup_ctrl_init_rfci_hdr *ihdr_rfci; + struct iuup_ctrl_init_tail *itail; + enum iuup_error_cause err_cause; + uint8_t num_rfci = 0; + int i; + bool is_last; + uint16_t remote_mask, match_mask; + struct osmo_iuup_rnl_prim *irp; + struct osmo_iuup_tnl_prim *resp; + + /* TODO: whenever we check message boundaries, length, etc. and we fail, send NACK */ + + hdr = (struct iuup_pdutype14_hdr *)msgb_l2(itp->oph.msg); + ihdr = (struct iuup_ctrl_init_hdr *)hdr->payload; + if (ihdr->num_subflows_per_rfci == 0) { + LOGPFSML(iui->fi, LOGL_NOTICE, "Initialization: Unexpected num_subflows=0 received\n"); + err_cause = IUUP_ERR_CAUSE_UNEXPECTED_VALUE; + goto send_nack; + } + ihdr_rfci = (struct iuup_ctrl_init_rfci_hdr *)ihdr->rfci_data; + + do { + struct osmo_iuup_rfci *rfci = &iui->config.rfci[num_rfci]; + uint8_t l_size_bytes = ihdr_rfci->li + 1; + is_last = ihdr_rfci->lri; + if (num_rfci >= IUUP_MAX_RFCIS) { + LOGPFSML(iui->fi, LOGL_NOTICE, "Initialization: Too many RFCIs received (%u)\n", + num_rfci); + err_cause = IUUP_ERR_CAUSE_UNEXPECTED_RFCI; + goto send_nack; + } + rfci->used = 1; + rfci->id = ihdr_rfci->rfci; + if (l_size_bytes == 2) { + uint16_t *subflow_size = (uint16_t *)ihdr_rfci->subflow_length; + for (i = 0; i < ihdr->num_subflows_per_rfci; i++) { + rfci->subflow_sizes[i] = osmo_load16be(subflow_size); + subflow_size++; + } + } else { + uint8_t *subflow_size = ihdr_rfci->subflow_length; + for (i = 0; i < ihdr->num_subflows_per_rfci; i++) { + rfci->subflow_sizes[i] = *subflow_size; + subflow_size++; + } + } + num_rfci++; + ihdr_rfci++; + ihdr_rfci = (struct iuup_ctrl_init_rfci_hdr *)(((uint8_t *)ihdr_rfci) + ihdr->num_subflows_per_rfci * l_size_bytes); + } while (!is_last); + + if (ihdr->ti) { /* Timing information present */ + uint8_t *buf = (uint8_t *)ihdr_rfci; + uint8_t num_bytes = (num_rfci + 1) / 2; + iui->config.IPTIs_present = true; + for (i = 0; i < num_bytes - 1; i++) { + iui->config.rfci[i*2].IPTI = *buf >> 4; + iui->config.rfci[i*2 + 1].IPTI = *buf & 0x0f; + buf++; + } + iui->config.rfci[i*2].IPTI = *buf >> 4; + if (!(num_rfci & 0x01)) /* is even: */ + iui->config.rfci[i*2 + 1].IPTI = *buf & 0x0f; + buf++; + itail = (struct iuup_ctrl_init_tail *)buf; + } else { + iui->config.IPTIs_present = false; + itail = (struct iuup_ctrl_init_tail *)ihdr_rfci; + } + if (itail->data_pdu_type > 1) { + LOGPFSML(iui->fi, LOGL_NOTICE, "Initialization: Unexpected Data PDU Type %u received\n", itail->data_pdu_type); + err_cause = IUUP_ERR_CAUSE_UNEXPECTED_VALUE; + goto send_nack; + } + + remote_mask = osmo_load16be(&itail->versions_supported); + match_mask = (remote_mask & iui->config.supported_versions_mask); + if (match_mask == 0x0000) { + LOGPFSML(iui->fi, LOGL_NOTICE, + "Initialization: No match in supported versions local=0x%04x vs remote=0x%04x\n", + iui->config.supported_versions_mask, remote_mask); + err_cause = IUUP_ERR_CAUSE_UNEXPECTED_VALUE; + goto send_nack; + } + for (i = 15; i >= 0; i--) { + if (match_mask & (1<<i)) { + iui->mode_version = i; + break; + } + } + + iui->config.num_rfci = num_rfci; + iui->config.num_subflows = ihdr->num_subflows_per_rfci; + iui->config.data_pdu_type = itail->data_pdu_type; + + irp = irp_init_ind_alloc(iui); + iui->user_prim_cb(&irp->oph, iui->user_prim_priv); + + LOGPFSML(iui->fi, LOGL_DEBUG, "Tx Initialization ACK\n"); + resp = itp_ctrl_ack_alloc(iui, IUUP_PROC_INIT, hdr->frame_nr); + iui->transport_prim_cb(&resp->oph, iui->transport_prim_priv); + return ihdr->chain_ind == 0; +send_nack: + LOGPFSML(iui->fi, LOGL_NOTICE, "Tx Initialization NACK cause=%u orig_message=%s\n", + err_cause, osmo_hexdump((const unsigned char *) msgb_l2(itp->oph.msg), msgb_l2len(itp->oph.msg))); + resp = tnp_ctrl_nack_alloc(iui, IUUP_PROC_INIT, err_cause, hdr->frame_nr); + iui->transport_prim_cb(&resp->oph, iui->transport_prim_priv); + return false; +} + +/********************** + * FSM STATE FUNCTIONS + **********************/ +static void iuup_fsm_null(struct osmo_fsm_inst *fi, uint32_t event, void *data) +{ + struct osmo_iuup_instance *iui = fi->priv; + struct osmo_iuup_rnl_prim *user_prim = NULL; + + switch (event) { + case IUUP_FSM_EVT_IUUP_CONFIG_REQ: + user_prim = data; + iui->config = user_prim->u.config; + iui->config.supported_versions_mask &= 0x0003; /* We only support versions 1 and 2 ourselves */ + //TODO: if supported_versions_mask == 0x0000,no supported versions, send error to upper layers + + if (iui->config.transparent) + osmo_fsm_inst_state_chg(fi, IUUP_FSM_ST_TrM_DATA_XFER_READY, 0, 0); + else { + osmo_fsm_inst_state_chg(fi, IUUP_FSM_ST_INIT, 0, 0); + } + break; + } +} + +/* transparent mode data transfer */ +static void iuup_fsm_trm_data(struct osmo_fsm_inst *fi, uint32_t event, void *data) +{ + //struct osmo_iuup_instance *iui = fi->priv; + + switch (event) { + case IUUP_FSM_EVT_IUUP_CONFIG_REQ: + osmo_fsm_inst_state_chg(fi, IUUP_FSM_ST_NULL, 0, 0); + break; + case IUUP_FSM_EVT_IUUP_DATA_REQ: + /* Data coming down from RNL (user) towards TNL (transport) */ + break; + case IUUP_FSM_EVT_IUUP_DATA_IND: + /* Data coming up from TNL (transport) towards RNL (user) */ + break; + case IUUP_FSM_EVT_IUUP_UNITDATA_REQ: + case IUUP_FSM_EVT_IUUP_UNITDATA_IND: + case IUUP_FSM_EVT_SSASAR_UNITDATA_REQ: + case IUUP_FSM_EVT_SSASAR_UNITDATA_IND: + /* no state change */ + break; + } +} + +static void iuup_fsm_init_on_enter(struct osmo_fsm_inst *fi, uint32_t prev_state) +{ + struct osmo_iuup_instance *iui = fi->priv; + + iui->type14_fn = 0; + if (iui->config.active) { + iui->timer.init.n = 0; + iui->timer.init.retrans_itp = tnp_ctrl_init_alloc(iui); + retransmit_initialization(iui); + } +} + +static void iuup_fsm_init(struct osmo_fsm_inst *fi, uint32_t event, void *data) +{ + struct osmo_iuup_instance *iui = fi->priv; + struct osmo_iuup_rnl_prim *irp; + struct osmo_iuup_tnl_prim *itp; + + switch (event) { + case IUUP_FSM_EVT_IUUP_CONFIG_REQ: + /* the only permitted 'config req' type is the request to release the instance */ + osmo_fsm_inst_state_chg(fi, IUUP_FSM_ST_NULL, 0, 0); + break; + case IUUP_FSM_EVT_INIT: + itp = data; + if (iuup_rx_initialization(iui, itp)) + osmo_fsm_inst_state_chg(fi, IUUP_FSM_ST_SMpSDU_DATA_XFER_READY, 0, 0); + break; + case IUUP_FSM_EVT_LAST_INIT_ACK: + /* last INIT ACK was received, transition to DATA_XFER_READY state */ + osmo_fsm_inst_state_chg(fi, IUUP_FSM_ST_SMpSDU_DATA_XFER_READY, 0, 0); + break; + case IUUP_FSM_EVT_INIT_NACK: + LOGPFSML(fi, LOGL_NOTICE, "Rx Initialization NACK N=%" PRIu32 "/%" PRIu32 "\n", + iui->timer.init.n, iui->config.t_init.n_max); + osmo_timer_del(&fi->timer); + if (iui->timer.init.n == iui->config.t_init.n_max) { + irp = irp_error_event_alloc_c(iui, IUUP_ERR_CAUSE_INIT_FAILURE_REP_NACK, IUUP_ERR_DIST_SECOND_FWD); + iui->user_prim_cb(&irp->oph, iui->user_prim_priv); + return; + } + iui->timer.init.n++; + retransmit_initialization(iui); + break; + default: + OSMO_ASSERT(false); + } +} + +/* 3GPP TS 25.415 B.2.3 "Support Mode Data Transfer Ready State" */ +static void iuup_fsm_smpsdu_data(struct osmo_fsm_inst *fi, uint32_t event, void *data) +{ + struct osmo_iuup_instance *iui = fi->priv; + struct osmo_iuup_rnl_prim *irp = NULL; + struct osmo_iuup_tnl_prim *itp = NULL; + + switch (event) { + case IUUP_FSM_EVT_IUUP_CONFIG_REQ: + irp = data; + osmo_fsm_inst_state_chg(fi, IUUP_FSM_ST_NULL, 0, 0); + break; + case IUUP_FSM_EVT_INIT: + /* "In case of handover or relocation, Initialisation procedures + * may have to be performed and Iu UP instance may have to enter + * the initialisation state." */ + itp = data; + if (!iuup_rx_initialization(iui, itp)) + osmo_fsm_inst_state_chg(fi, IUUP_FSM_ST_INIT, 0, 0); + break; + case IUUP_FSM_EVT_IUUP_DATA_REQ: + /* Data coming down from RNL (user) towards TNL (transport) */ + irp = data; + itp = rnl_to_tnl_data(iui, irp); + iui->transport_prim_cb(&itp->oph, iui->transport_prim_priv); + break; + case IUUP_FSM_EVT_IUUP_DATA_IND: + /* Data coming up from TNL (transport) towards RNL (user) */ + itp = data; + irp = tnl_to_rnl_data(itp); + iui->user_prim_cb(&irp->oph, iui->user_prim_priv); + break; + } +} + +static int iuup_fsm_timer_cb(struct osmo_fsm_inst *fi) +{ + struct osmo_iuup_instance *iui = fi->priv; + struct osmo_iuup_rnl_prim *irp; + + switch (fi->T) { + case IUUP_TIMER_INIT: + OSMO_ASSERT(fi->state == IUUP_FSM_ST_INIT); + if (iui->timer.init.n == iui->config.t_init.n_max) { + irp = irp_error_event_alloc_c(iui, IUUP_ERR_CAUSE_INIT_FAILURE_NET_TMR, IUUP_ERR_DIST_LOCAL); + iui->user_prim_cb(&irp->oph, iui->user_prim_priv); + return 0; + } + iui->timer.init.n++; + retransmit_initialization(iui); + break; + case IUUP_TIMER_TA: + break; + case IUUP_TIMER_RC: + break; + default: + OSMO_ASSERT(0); + } + return 0; +} + + +static const struct osmo_fsm_state iuup_fsm_states[] = { + [IUUP_FSM_ST_NULL] = { + .in_event_mask = S(IUUP_FSM_EVT_IUUP_CONFIG_REQ), + .out_state_mask = S(IUUP_FSM_ST_INIT) | + S(IUUP_FSM_ST_TrM_DATA_XFER_READY), + .name = "NULL", + .action = iuup_fsm_null, + }, + [IUUP_FSM_ST_TrM_DATA_XFER_READY] = { + .in_event_mask = S(IUUP_FSM_EVT_IUUP_CONFIG_REQ) | + S(IUUP_FSM_EVT_IUUP_STATUS_REQ) | + S(IUUP_FSM_EVT_IUUP_DATA_REQ) | + S(IUUP_FSM_EVT_IUUP_DATA_IND) | + S(IUUP_FSM_EVT_IUUP_UNITDATA_REQ) | + S(IUUP_FSM_EVT_IUUP_UNITDATA_IND) | + S(IUUP_FSM_EVT_SSASAR_UNITDATA_REQ) | + S(IUUP_FSM_EVT_SSASAR_UNITDATA_IND), + .out_state_mask = S(IUUP_FSM_ST_NULL), + .name = "TrM_Data_Transfer_Ready", + .action = iuup_fsm_trm_data, + }, + [IUUP_FSM_ST_INIT] = { + .in_event_mask = S(IUUP_FSM_EVT_IUUP_CONFIG_REQ) | + S(IUUP_FSM_EVT_INIT) | + S(IUUP_FSM_EVT_LAST_INIT_ACK) | + S(IUUP_FSM_EVT_INIT_NACK), + .out_state_mask = S(IUUP_FSM_ST_NULL) | + S(IUUP_FSM_ST_SMpSDU_DATA_XFER_READY), + .name = "Initialisation", + .onenter = iuup_fsm_init_on_enter, + .action = iuup_fsm_init, + }, + [IUUP_FSM_ST_SMpSDU_DATA_XFER_READY] = { + .in_event_mask = S(IUUP_FSM_EVT_IUUP_CONFIG_REQ) | + S(IUUP_FSM_EVT_INIT) | + S(IUUP_FSM_EVT_IUUP_DATA_REQ) | + S(IUUP_FSM_EVT_IUUP_DATA_IND), + .out_state_mask = S(IUUP_FSM_ST_NULL) | + S(IUUP_FSM_ST_INIT), + .name = "SMpSDU_Data_Transfer_Ready", + .action = iuup_fsm_smpsdu_data, + }, +}; + +static struct osmo_fsm iuup_fsm = { + .name = "IuUP", + .states = iuup_fsm_states, + .num_states = ARRAY_SIZE(iuup_fsm_states), + .timer_cb = iuup_fsm_timer_cb, + .log_subsys = DLIUUP, + .event_names = iuup_fsm_event_names, +}; + +static int iuup_verify_pdu(const uint8_t *data, unsigned int len) +{ + int header_crc_computed, payload_crc_computed; + uint16_t payload_crc; + uint8_t pdu_type = iuup_get_pdu_type(data); + struct iuup_pdutype0_hdr *t0h; + struct iuup_pdutype14_hdr *t14h; + + if (len < 3) + return -EINVAL; + + header_crc_computed = osmo_iuup_compute_header_crc(data, len); + if (iuup_get_hdr_crc(data) != header_crc_computed) { + LOGP(DLIUUP, LOGL_NOTICE, "Header Checksum error: rx 0x%02x vs exp 0x%02x\n", + iuup_get_hdr_crc(data), header_crc_computed); + return -EIO; + } + switch (pdu_type) { + case IUUP_PDU_T_DATA_NOCRC: + if (len < 4) + return -EINVAL; + break; + case IUUP_PDU_T_DATA_CRC: + t0h = (struct iuup_pdutype0_hdr *) data; + payload_crc = ((uint16_t)t0h->payload_crc_hi << 8) | t0h->payload_crc_lo; + payload_crc_computed = osmo_iuup_compute_payload_crc(data, len); + if (payload_crc != payload_crc_computed) + goto payload_crc_err; + break; + case IUUP_PDU_T_CONTROL: + t14h = (struct iuup_pdutype14_hdr *) data; + if (t14h->ack_nack == IUUP_AN_PROCEDURE) { + payload_crc = ((uint16_t)t14h->payload_crc_hi << 8) | t14h->payload_crc_lo; + payload_crc_computed = osmo_iuup_compute_payload_crc(data, len); + if (payload_crc != payload_crc_computed) + goto payload_crc_err; + } + break; + default: + return -EINVAL; + } + return 0; + +payload_crc_err: + LOGP(DLIUUP, LOGL_NOTICE, "Payload Checksum error (pdu type %u): rx 0x%02x vs exp 0x%02x\n", + pdu_type, payload_crc, payload_crc_computed); + return -EIO; +} + +/* A IuUP TNL SAP primitive from transport (lower layer) */ +int osmo_iuup_tnl_prim_up(struct osmo_iuup_instance *inst, struct osmo_iuup_tnl_prim *itp) +{ + struct osmo_prim_hdr *oph = &itp->oph; + struct iuup_pdutype14_hdr *t14h; + int rc = 0; + + OSMO_ASSERT(oph->sap == SAP_IUUP_TNL); + + switch (OSMO_PRIM_HDR(oph)) { + case OSMO_PRIM(OSMO_IUUP_TNL_UNITDATA, PRIM_OP_INDICATION): + if (iuup_verify_pdu(msgb_l2(oph->msg), msgb_l2len(oph->msg)) < 0) { + LOGPFSML(inst->fi, LOGL_NOTICE, "Discarding invalid IuUP PDU: %s\n", + osmo_hexdump((const unsigned char *) msgb_l2(oph->msg), msgb_l2len(oph->msg))); + /* don't return error as the caller is not responsible for the PDU which + * was transmitted from some remote peer */ + return 0; + } + switch (iuup_get_pdu_type(msgb_l2(oph->msg))) { + case IUUP_PDU_T_DATA_CRC: + oph->msg->l3h = msgb_l2(oph->msg) + sizeof(struct iuup_pdutype0_hdr); + rc = osmo_fsm_inst_dispatch(inst->fi, IUUP_FSM_EVT_IUUP_DATA_IND, itp); + break; + case IUUP_PDU_T_DATA_NOCRC: + oph->msg->l3h = msgb_l2(oph->msg) + sizeof(struct iuup_pdutype1_hdr); + rc = osmo_fsm_inst_dispatch(inst->fi, IUUP_FSM_EVT_IUUP_DATA_IND, itp); + break; + case IUUP_PDU_T_CONTROL: + t14h = (struct iuup_pdutype14_hdr *) msgb_l2(oph->msg); + switch (t14h->ack_nack) { + case IUUP_AN_PROCEDURE: + switch (t14h->proc_ind) { + case IUUP_PROC_INIT: + rc = osmo_fsm_inst_dispatch(inst->fi, IUUP_FSM_EVT_INIT, itp); + break; + case IUUP_PROC_RATE_CTRL: + case IUUP_PROC_TIME_ALIGN: + case IUUP_PROC_ERR_EVENT: + LOGPFSML(inst->fi, LOGL_NOTICE, "Received Request for " + "unsupported IuUP procedure %u\n", t14h->proc_ind); + break; + default: + LOGPFSML(inst->fi, LOGL_NOTICE, "Received Request for " + "unknown IuUP procedure %u\n", t14h->proc_ind); + break; + } + break; + case IUUP_AN_ACK: + switch (t14h->proc_ind) { + case IUUP_PROC_INIT: + rc = osmo_fsm_inst_dispatch(inst->fi, + IUUP_FSM_EVT_LAST_INIT_ACK, itp); + break; + default: + LOGPFSML(inst->fi, LOGL_ERROR, "Received ACK for " + "unknown IuUP procedure %u\n", t14h->proc_ind); + break; + } + break; + case IUUP_AN_NACK: + switch (t14h->proc_ind) { + case IUUP_PROC_INIT: + rc = osmo_fsm_inst_dispatch(inst->fi, + IUUP_FSM_EVT_INIT_NACK, itp); + break; + default: + LOGPFSML(inst->fi, LOGL_ERROR, "Received NACK for " + "unknown IuUP procedure %u\n", t14h->proc_ind); + break; + } + break; + default: + LOGPFSML(inst->fi, LOGL_ERROR, "Received unknown IuUP ACK/NACK\n"); + break; + } + break; + default: + LOGPFSML(inst->fi, LOGL_NOTICE, "Received unknown IuUP PDU type %u\n", + iuup_get_pdu_type(msgb_l2(oph->msg))); + break; + } + break; + default: + /* exception: return an error code due to a wrong primitive */ + return -EINVAL; + } + + return rc; +} + +/* A IuUP RNL SAP primitive from user (higher layer) */ +int osmo_iuup_rnl_prim_down(struct osmo_iuup_instance *inst, struct osmo_iuup_rnl_prim *irp) +{ + struct osmo_prim_hdr *oph = &irp->oph; + int rc; + + OSMO_ASSERT(oph->sap == SAP_IUUP_RNL); + + switch (OSMO_PRIM_HDR(oph)) { + case OSMO_PRIM(OSMO_IUUP_RNL_CONFIG, PRIM_OP_REQUEST): + rc = osmo_fsm_inst_dispatch(inst->fi, IUUP_FSM_EVT_IUUP_CONFIG_REQ, irp); + msgb_free(irp->oph.msg); + break; + case OSMO_PRIM(OSMO_IUUP_RNL_DATA, PRIM_OP_REQUEST): + rc = osmo_fsm_inst_dispatch(inst->fi, IUUP_FSM_EVT_IUUP_DATA_REQ, irp); + if (rc != 0) + msgb_free(irp->oph.msg); + break; + case OSMO_PRIM(OSMO_IUUP_RNL_STATUS, PRIM_OP_REQUEST): + rc = osmo_fsm_inst_dispatch(inst->fi, IUUP_FSM_EVT_IUUP_STATUS_REQ, irp); + msgb_free(irp->oph.msg); + break; + default: + rc = -EINVAL; + msgb_free(irp->oph.msg); + } + return rc; +} + +struct osmo_iuup_instance *osmo_iuup_instance_alloc(void *ctx, const char *id) +{ + struct osmo_iuup_instance *iui; + iui = talloc_zero(ctx, struct osmo_iuup_instance); + if (!iui) + return NULL; + + iui->fi = osmo_fsm_inst_alloc(&iuup_fsm, NULL, iui, LOGL_DEBUG, id); + if (!iui->fi) + goto free_ret; + + return iui; +free_ret: + talloc_free(iui); + return NULL; +} + +void osmo_iuup_instance_free(struct osmo_iuup_instance *iui) +{ + if (!iui) + return; + + if (iui->fi) + osmo_fsm_inst_free(iui->fi); + iui->fi = NULL; + talloc_free(iui); +} + +void osmo_iuup_instance_set_user_prim_cb(struct osmo_iuup_instance *iui, osmo_prim_cb func, void *priv) +{ + iui->user_prim_cb = func; + iui->user_prim_priv = priv; +} +void osmo_iuup_instance_set_transport_prim_cb(struct osmo_iuup_instance *iui, osmo_prim_cb func, void *priv) +{ + iui->transport_prim_cb = func; + iui->transport_prim_priv = priv; +} + +static __attribute__((constructor)) void on_dso_load_iuup_fsm(void) +{ + OSMO_ASSERT(osmo_fsm_register(&iuup_fsm) == 0); +} |