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#include <stdint.h>
#include <unistd.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <osmocom/core/select.h>
#include <osmocom/core/prim.h>
#include <osmocom/core/talloc.h>
#include <osmocom/core/logging.h>
#include <osmocom/core/application.h>
#include <osmocom/vty/logging.h>
#include <osmocom/gsm/gsm48.h>
#include <osmocom/gprs/gprs_msgb.h>
#include <osmocom/sigtran/sua.h>
#include <osmocom/sigtran/sccp_sap.h>
#include <openbsc/gprs_sgsn.h>
#include <openbsc/iu.h>
#include <openbsc/debug.h>
#include <osmocom/ranap/ranap_ies_defs.h>
#include <osmocom/ranap/ranap_common.h>
#include <osmocom/ranap/ranap_common_cn.h>
#include <osmocom/ranap/ranap_msg_factory.h>
#include <asn1c/asn1helpers.h>
int asn1_xer_print = 1;
void *talloc_asn1_ctx;
iu_recv_cb_t global_iu_recv_cb = NULL;
static LLIST_HEAD(ue_conn_ctx_list);
struct ue_conn_ctx *ue_conn_ctx_alloc(struct osmo_sua_link *link, uint32_t conn_id)
{
struct ue_conn_ctx *ctx = talloc_zero(NULL, struct ue_conn_ctx);
ctx->link = link;
ctx->conn_id = conn_id;
llist_add(&ctx->list, &ue_conn_ctx_list);
return ctx;
}
struct ue_conn_ctx *ue_conn_ctx_find(struct osmo_sua_link *link, uint32_t conn_id)
{
struct ue_conn_ctx *ctx;
llist_for_each_entry(ctx, &ue_conn_ctx_list, list) {
if (ctx->link == link && ctx->conn_id == conn_id)
return ctx;
}
return NULL;
}
/***********************************************************************
* RANAP handling
***********************************************************************/
static int iu_rab_act(struct ue_conn_ctx *ue_ctx, struct msgb *msg)
{
struct osmo_scu_prim *prim;
/* wrap RANAP message in SCCP N-DATA.req */
prim = (struct osmo_scu_prim *) msgb_push(msg, sizeof(*prim));
prim->u.data.conn_id = ue_ctx->conn_id;
osmo_prim_init(&prim->oph,
SCCP_SAP_USER,
OSMO_SCU_PRIM_N_DATA,
PRIM_OP_REQUEST,
msg);
return osmo_sua_user_link_down(ue_ctx->link, &prim->oph);
}
int iu_rab_act_cs(struct ue_conn_ctx *ue_ctx, uint32_t rtp_ip, uint16_t rtp_port)
{
struct msgb *msg;
msg = ranap_new_msg_rab_assign_voice(1, rtp_ip, rtp_port);
msg->l2h = msg->data;
return iu_rab_act(ue_ctx, msg);
}
int iu_rab_act_ps(struct ue_conn_ctx *ue_ctx, uint32_t gtp_ip, uint32_t gtp_tei)
{
struct msgb *msg;
msg = ranap_new_msg_rab_assign_data(1, gtp_ip, gtp_tei);
msg->l2h = msg->data;
return iu_rab_act(ue_ctx, msg);
}
int gprs_iu_rab_deact(struct sgsn_mm_ctx *mm)
{
/* FIXME */
return -1;
}
int gprs_transp_upd_key(struct sgsn_mm_ctx *mm)
{
struct gsm_auth_tuple *tp = &mm->auth_triplet;
if (mm->ran_type == MM_CTX_T_UTRAN_Iu) {
struct ue_conn_ctx *uectx;
struct osmo_scu_prim *prim;
struct msgb *msg;
uint8_t ik[16];
uint8_t ck[16];
unsigned int i;
uectx = mm->iu.ue_ctx;
/* C4 function to dervie CK from Kc */
memcpy(ck, tp->kc, 8);
memcpy(ck+8, tp->kc, 8);
/* C5 function to derive IK from Kc */
for (i = 0; i < 4; i++)
ik[i] = tp->kc[i] ^ tp->kc[i+4];
memcpy(ik+4, tp->kc, 8);
for (i = 12; i < 16; i++)
ik[i] = ik[i-12];
/* crate RANAP message */
msg = ranap_new_msg_sec_mod_cmd(ik, NULL);
msg->l2h = msg->data;
/* wrap RANAP message in SCCP N-DATA.req */
prim = (struct osmo_scu_prim *) msgb_push(msg, sizeof(*prim));
prim->u.data.conn_id = uectx->conn_id;
osmo_prim_init(&prim->oph, SCCP_SAP_USER,
OSMO_SCU_PRIM_N_DATA,
PRIM_OP_REQUEST, msg);
osmo_sua_user_link_down(uectx->link, &prim->oph);
}
return 0;
}
static int ranap_handle_co_initial_ue(void *ctx, RANAP_InitialUE_MessageIEs_t *ies)
{
struct gprs_ra_id ra_id;
uint16_t sai;
struct msgb *msg = msgb_alloc(256, "RANAP->NAS");
ranap_parse_lai(&ra_id, &ies->lai);
sai = asn1str_to_u16(&ies->sai.sAC);
msgb_gmmh(msg) = msgb_put(msg, ies->nas_pdu.size);
memcpy(msgb_gmmh(msg), ies->nas_pdu.buf, ies->nas_pdu.size);
/* Feed into the MM layer */
msg->dst = ctx;
global_iu_recv_cb(msg, &ra_id, &sai);
return 0;
}
static int ranap_handle_co_dt(void *ctx, RANAP_DirectTransferIEs_t *ies)
{
struct gprs_ra_id _ra_id, *ra_id = NULL;
uint16_t _sai, *sai = NULL;
struct msgb *msg = msgb_alloc(256, "RANAP->NAS");
if (ies->presenceMask & DIRECTTRANSFERIES_RANAP_LAI_PRESENT) {
ranap_parse_lai(&_ra_id, &ies->lai);
ra_id = &_ra_id;
if (ies->presenceMask & DIRECTTRANSFERIES_RANAP_RAC_PRESENT) {
_ra_id.rac = asn1str_to_u8(&ies->rac);
}
if (ies->presenceMask & DIRECTTRANSFERIES_RANAP_SAI_PRESENT) {
_sai = asn1str_to_u16(&ies->sai.sAC);
sai = &_sai;
}
}
msgb_gmmh(msg) = msgb_put(msg, ies->nas_pdu.size);
memcpy(msgb_gmmh(msg), ies->nas_pdu.buf, ies->nas_pdu.size);
/* Feed into the MM/CC/SMS-CP layer */
msg->dst = ctx;
global_iu_recv_cb(msg, ra_id, sai);
return 0;
}
static int ranap_handle_co_err_ind(void *ctx, RANAP_ErrorIndicationIEs_t *ies)
{
if (ies->presenceMask & ERRORINDICATIONIES_RANAP_CAUSE_PRESENT)
LOGP(DRANAP, LOGL_ERROR, "Rx Error Indication (%s)\n",
ranap_cause_str(&ies->cause));
else
LOGP(DRANAP, LOGL_ERROR, "Rx Error Indication\n");
return 0;
}
int iu_tx(struct msgb *msg, uint8_t sapi)
{
struct ue_conn_ctx *uectx = msg->dst;
struct osmo_scu_prim *prim;
LOGP(DRANAP, LOGL_INFO, "Transmitting L3 Message as RANAP DT\n");
msg = ranap_new_msg_dt(sapi, msg->data, msgb_length(msg));
msg->l2h = msg->data;
prim = (struct osmo_scu_prim *) msgb_push(msg, sizeof(*prim));
prim->u.data.conn_id = uectx->conn_id;
osmo_prim_init(&prim->oph, SCCP_SAP_USER,
OSMO_SCU_PRIM_N_DATA,
PRIM_OP_REQUEST, msg);
osmo_sua_user_link_down(uectx->link, &prim->oph);
return 0;
}
static int ranap_handle_co_iu_rel_req(struct ue_conn_ctx *ctx, RANAP_Iu_ReleaseRequestIEs_t *ies)
{
struct msgb *msg;
struct osmo_scu_prim *prim;
LOGP(DRANAP, LOGL_INFO, "Received Iu Release Request, Sending Release Command\n");
msg = ranap_new_msg_iu_rel_cmd(&ies->cause);
msg->l2h = msg->data;
prim = (struct osmo_scu_prim *) msgb_push(msg, sizeof(*prim));
prim->u.data.conn_id = ctx->conn_id;
osmo_prim_init(&prim->oph, SCCP_SAP_USER,
OSMO_SCU_PRIM_N_DATA,
PRIM_OP_REQUEST, msg);
osmo_sua_user_link_down(ctx->link, &prim->oph);
return 0;
}
static int ranap_handle_co_rab_ass_resp(void *ctx, RANAP_RAB_AssignmentResponseIEs_t *ies)
{
int rc;
LOGP(DRANAP, LOGL_INFO, "RAB Asignment Response:");
if (ies->presenceMask & RAB_ASSIGNMENTRESPONSEIES_RANAP_RAB_SETUPORMODIFIEDLIST_PRESENT) {
RANAP_RAB_SetupOrModifiedItemIEs_t setup_ies;
RANAP_RAB_SetupOrModifiedItem_t *item = &setup_ies.raB_SetupOrModifiedItem;
rc = ranap_decode_rab_setupormodifieditemies(&setup_ies,
(ANY_t *)&ies->raB_SetupOrModifiedList);
if (item->transportLayerAddress) {
uint8_t rab_id = item->rAB_ID.buf[0];
LOGPC(DRANAP, LOGL_INFO, " Setup: (%u/%s)",
rab_id,
osmo_hexdump(item->transportLayerAddress->buf,
item->transportLayerAddress->size));
}
}
LOGPC(DRANAP, LOGL_INFO, "\n");
return rc;
}
/* Entry point for connection-oriented RANAP message */
static void cn_ranap_handle_co(void *ctx, ranap_message *message)
{
int rc;
LOGP(DRANAP, LOGL_NOTICE, "handle_co(dir=%u, proc=%u)\n", message->direction, message->procedureCode);
switch (message->direction) {
case RANAP_RANAP_PDU_PR_initiatingMessage:
switch (message->procedureCode) {
case RANAP_ProcedureCode_id_InitialUE_Message:
rc = ranap_handle_co_initial_ue(ctx, &message->msg.initialUE_MessageIEs);
break;
case RANAP_ProcedureCode_id_DirectTransfer:
rc = ranap_handle_co_dt(ctx, &message->msg.directTransferIEs);
break;
case RANAP_ProcedureCode_id_ErrorIndication:
rc = ranap_handle_co_err_ind(ctx, &message->msg.errorIndicationIEs);
break;
case RANAP_ProcedureCode_id_Iu_ReleaseRequest:
/* Iu Release Request */
rc = ranap_handle_co_iu_rel_req(ctx, &message->msg.iu_ReleaseRequestIEs);
break;
default:
rc = -1;
break;
}
break;
case RANAP_RANAP_PDU_PR_successfulOutcome:
switch (message->procedureCode) {
case RANAP_ProcedureCode_id_RAB_Assignment:
/* RAB Assignment Response */
rc = ranap_handle_co_rab_ass_resp(ctx, &message->msg.raB_AssignmentResponseIEs);
break;
case RANAP_ProcedureCode_id_SecurityModeControl:
/* Security Mode Complete */
rc = -1;
break;
case RANAP_ProcedureCode_id_Iu_Release:
/* Iu Release Complete */
rc = -1;
break;
default:
rc = -1;
break;
}
case RANAP_RANAP_PDU_PR_unsuccessfulOutcome:
case RANAP_RANAP_PDU_PR_outcome:
default:
rc = -1;
break;
}
if (rc) {
LOGP(DRANAP, LOGL_ERROR, "Error in cn_ranap_handle_co (%d)\n",
rc);
/* TODO handling of the error? */
}
}
static int ranap_handle_cl_reset_req(void *ctx, RANAP_ResetIEs_t *ies)
{
/* FIXME: send reset response */
return -1;
}
static int ranap_handle_cl_err_ind(void *ctx, RANAP_ErrorIndicationIEs_t *ies)
{
if (ies->presenceMask & ERRORINDICATIONIES_RANAP_CAUSE_PRESENT)
LOGP(DRANAP, LOGL_ERROR, "Rx Error Indication (%s)\n",
ranap_cause_str(&ies->cause));
else
LOGP(DRANAP, LOGL_ERROR, "Rx Error Indication\n");
return 0;
}
/* Entry point for connection-less RANAP message */
static void cn_ranap_handle_cl(void *ctx, ranap_message *message)
{
int rc;
switch (message->direction) {
case RANAP_RANAP_PDU_PR_initiatingMessage:
switch (message->procedureCode) {
case RANAP_ProcedureCode_id_Reset:
/* received reset.req, send reset.resp */
rc = ranap_handle_cl_reset_req(ctx, &message->msg.resetIEs);
break;
case RANAP_ProcedureCode_id_ErrorIndication:
rc = ranap_handle_cl_err_ind(ctx, &message->msg.errorIndicationIEs);
break;
default:
rc = -1;
break;
}
break;
case RANAP_RANAP_PDU_PR_successfulOutcome:
case RANAP_RANAP_PDU_PR_unsuccessfulOutcome:
case RANAP_RANAP_PDU_PR_outcome:
default:
rc = -1;
break;
}
if (rc) {
LOGP(DRANAP, LOGL_ERROR, "Error in cn_ranap_handle_cl (%d)\n",
rc);
/* TODO handling of the error? */
}
}
/***********************************************************************
*
***********************************************************************/
int tx_unitdata(struct osmo_sua_link *link);
int tx_conn_req(struct osmo_sua_link *link, uint32_t conn_id);
struct osmo_prim_hdr *make_conn_req(uint32_t conn_id);
struct osmo_prim_hdr *make_dt1_req(uint32_t conn_id, const uint8_t *data, unsigned int len);
struct osmo_prim_hdr *make_conn_resp(struct osmo_scu_connect_param *param)
{
struct msgb *msg = msgb_alloc(1024, "conn_resp");
struct osmo_scu_prim *prim;
prim = (struct osmo_scu_prim *) msgb_put(msg, sizeof(*prim));
osmo_prim_init(&prim->oph, SCCP_SAP_USER,
OSMO_SCU_PRIM_N_CONNECT,
PRIM_OP_RESPONSE, msg);
memcpy(&prim->u.connect, param, sizeof(prim->u.connect));
return &prim->oph;
}
static int sccp_sap_up(struct osmo_prim_hdr *oph, void *link)
{
struct osmo_scu_prim *prim = (struct osmo_scu_prim *) oph;
struct osmo_prim_hdr *resp = NULL;
int rc;
struct ue_conn_ctx *ue;
printf("sccp_sap_up(%s)\n", osmo_scu_prim_name(oph));
switch (OSMO_PRIM_HDR(oph)) {
case OSMO_PRIM(OSMO_SCU_PRIM_N_CONNECT, PRIM_OP_CONFIRM):
/* confirmation of outbound connection */
rc = -1;
break;
case OSMO_PRIM(OSMO_SCU_PRIM_N_CONNECT, PRIM_OP_INDICATION):
/* indication of new inbound connection request*/
printf("N-CONNECT.ind(X->%u)\n", prim->u.connect.conn_id);
if (/* prim->u.connect.called_addr.ssn != OSMO_SCCP_SSN_RANAP || */
!msgb_l2(oph->msg) || msgb_l2len(oph->msg) == 0) {
LOGP(DGPRS, LOGL_NOTICE, "Received invalid N-CONNECT.ind\n");
return 0;
}
ue = ue_conn_ctx_alloc(link, prim->u.connect.conn_id);
/* first ensure the local SUA/SCCP socket is ACTIVE */
resp = make_conn_resp(&prim->u.connect);
osmo_sua_user_link_down(link, resp);
/* then handle the RANAP payload */
rc = ranap_cn_rx_co(cn_ranap_handle_co, ue, msgb_l2(oph->msg), msgb_l2len(oph->msg));
break;
case OSMO_PRIM(OSMO_SCU_PRIM_N_DISCONNECT, PRIM_OP_INDICATION):
/* indication of disconnect */
printf("N-DISCONNECT.ind(%u)\n", prim->u.disconnect.conn_id);
ue = ue_conn_ctx_find(link, prim->u.disconnect.conn_id);
rc = ranap_cn_rx_co(cn_ranap_handle_co, ue, msgb_l2(oph->msg), msgb_l2len(oph->msg));
break;
case OSMO_PRIM(OSMO_SCU_PRIM_N_DATA, PRIM_OP_INDICATION):
/* connection-oriented data received */
printf("N-DATA.ind(%u, %s)\n", prim->u.data.conn_id,
osmo_hexdump(msgb_l2(oph->msg), msgb_l2len(oph->msg)));
/* resolve UE context */
ue = ue_conn_ctx_find(link, prim->u.data.conn_id);
rc = ranap_cn_rx_co(cn_ranap_handle_co, ue, msgb_l2(oph->msg), msgb_l2len(oph->msg));
break;
case OSMO_PRIM(OSMO_SCU_PRIM_N_UNITDATA, PRIM_OP_INDICATION):
/* connection-oriented data received */
printf("N-UNITDATA.ind(%s)\n",
osmo_hexdump(msgb_l2(oph->msg), msgb_l2len(oph->msg)));
rc = ranap_cn_rx_cl(cn_ranap_handle_cl, link, msgb_l2(oph->msg), msgb_l2len(oph->msg));
break;
default:
rc = -1;
break;
}
msgb_free(oph->msg);
return rc;
}
int iu_init(void *ctx, const char *listen_addr, uint16_t listen_port,
iu_recv_cb_t iu_recv_cb)
{
struct osmo_sua_user *user;
talloc_asn1_ctx = talloc_named_const(ctx, 1, "asn1");
global_iu_recv_cb = iu_recv_cb;
osmo_sua_set_log_area(DSUA);
user = osmo_sua_user_create(ctx, sccp_sap_up, ctx);
return osmo_sua_server_listen(user, listen_addr, listen_port);
}
/* Return an existing Iu-CS subscriber connection record for the given link and
* connection IDs, or return NULL if not found. */
/* TODO wrong file */
static struct gsm_subscriber_connection *subscr_conn_lookup_iu(struct gsm_network *network,
uint8_t link_id,
uint32_t conn_id)
{
struct gsm_subscriber_connection *conn;
llist_for_each_entry(conn, &network->subscr_conns, entry) {
if (conn->via_iface != IFACE_IUCS)
continue;
if (conn->iu.link_id != link_id)
continue;
if (conn->iu.conn_id != conn_id)
continue;
return conn;
}
return NULL;
}
/* Receive MM/CC message from Iu-CS (SCCP user SAP).
* msg->dst must reference a struct ue_conn_ctx. link_id identifies the SCTP
* peer that sent the msg.
*
* For A-interface see libbsc/bsc_api.c gsm0408_rcvmsg(). */
/* TODO wrong file */
int gsm0408_rcvmsg_iucs(struct gsm_network *network, struct msgb *msg, uint8_t link_id)
{
int rc;
struct ue_conn_ctx *ue_ctx;
struct gsm_subscriber_connection *conn;
ue_ctx = (struct ue_conn_ctx*)msg->dst;
/* TODO: are there message types that could allow us to skip this
* search? */
conn = subscr_conn_lookup_iu(network, link_id, ue_ctx->conn_id);
if (conn) {
/* if we already have a connection, handle DTAP.
gsm0408_dispatch() is aka msc_dtap() */
gsm0408_dispatch(conn, msg);
} else {
/* allocate a new connection */
/* TODO */
#if 0
rc = BSC_API_CONN_POL_REJECT;
conn = subscr_conn_allocate_iu(msg->lchan);
if (!lchan->conn) {
lchan_release(lchan, 1, RSL_REL_NORMAL);
return -1;
}
/* fwd via bsc_api to send COMPLETE L3 INFO to MSC */
rc = api->compl_l3(lchan->conn, msg, 0);
if (rc != BSC_API_CONN_POL_ACCEPT) {
lchan->conn->lchan = NULL;
subscr_con_free(lchan->conn);
lchan_release(lchan, 1, RSL_REL_NORMAL);
}
#endif
}
return 0;
}
/* For A-interface see libbsc/bsc_api.c subscr_con_allocate() */
/* TODO wrong file */
struct gsm_subscriber_connection *subscr_conn_allocate_iu(struct gsm_bts *bts)
/* TODO "bts"? this is an hNodeB, really. */
{
struct gsm_subscriber_connection *conn;
conn = talloc_zero(bts->network, struct gsm_subscriber_connection);
if (!conn)
return NULL;
conn->via_iface = IFACE_IUCS;
conn->bts = bts;
llist_add_tail(&conn->entry, &bts->network->subscr_conns);
return conn;
}
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