mncc: rework passing GCR over the MNCC interface

Using *unpacked* 'struct osmo_gcr_parsed' in the MNCC PDUs makes
the protocol even more complicated than it currently is, and
moreover complicates implementing MNCCv8 in the ttcn3-sip-test.

Replace 'struct osmo_gcr_parsed' in 'struct gsm_mncc' with a
fixed-length buffer, which is supposed to hold the Global Call
Reference encoded as per 3GPP TS 29.205.

Check / indicate presence of GCR using the MNCC_F_GCR flag.

Change-Id: Iaff46732948f8f5d03e42f17c35cbac8a80af49b
Fixes: Id40d7e0fed9356f801b3627c118150055e7232b1
Related: OS#5164, OS#5282
This commit is contained in:
Vadim Yanitskiy 2021-10-27 16:40:21 +03:00
parent f3eb44f54b
commit bd66804082
2 changed files with 31 additions and 6 deletions

View File

@ -485,6 +485,7 @@ static void check_setup(struct mncc_connection *conn, const char *buf, int rc)
const struct gsm_mncc_number *called;
struct call *call;
struct mncc_call_leg *leg;
struct osmo_gcr_parsed gcr;
if (rc < sizeof(*data)) {
LOGP(DMNCC, LOGL_ERROR, "gsm_mncc of wrong size %d vs. %zu\n",
@ -525,6 +526,16 @@ static void check_setup(struct mncc_connection *conn, const char *buf, int rc)
return;
}
/* Decode the Global Call Reference (if present) */
if (data->fields & MNCC_F_GCR) {
if (osmo_dec_gcr(&gcr, data->gcr, sizeof(data->gcr)) < 0) {
LOGP(DMNCC, LOGL_ERROR,
"MNCC leg(%u) failed to parse GCR\n", data->callref);
mncc_send(conn, MNCC_REJ_REQ, data->callref);
return;
}
}
/* Create an RTP port and then allocate a call */
call = call_mncc_create();
if (!call) {
@ -543,12 +554,15 @@ static void check_setup(struct mncc_connection *conn, const char *buf, int rc)
leg->conn = conn;
leg->state = MNCC_CC_INITIAL;
leg->dir = MNCC_DIR_MO;
leg->base.call->gcr = data->gcr;
leg->base.call->gcr_present = true;
memcpy(&leg->called, called, sizeof(leg->called));
memcpy(&leg->calling, &data->calling, sizeof(leg->calling));
memcpy(&leg->imsi, data->imsi, sizeof(leg->imsi));
if (data->fields & MNCC_F_GCR) {
leg->base.call->gcr_present = true;
leg->base.call->gcr = gcr;
}
LOGP(DMNCC, LOGL_INFO,
"Created call(%u) with MNCC leg(%u) IMSI(%.16s)\n",
call->id, leg->callref, data->imsi);
@ -873,6 +887,7 @@ int mncc_create_remote_leg(struct mncc_connection *conn, struct call *call)
{
struct mncc_call_leg *leg;
struct gsm_mncc mncc = { 0, };
struct msgb *msg;
int rc;
leg = talloc_zero(call, struct mncc_call_leg);
@ -900,8 +915,6 @@ int mncc_create_remote_leg(struct mncc_connection *conn, struct call *call)
mncc.fields |= MNCC_F_CALLING;
mncc.calling.plan = GSM48_NPI_ISDN_E164;
if (call->gcr_present)
mncc.gcr = call->gcr;
if (call->source && call->source[0] == '+') {
mncc.calling.type = GSM48_TON_INTERNATIONAL;
@ -920,6 +933,16 @@ int mncc_create_remote_leg(struct mncc_connection *conn, struct call *call)
OSMO_STRLCPY_ARRAY(mncc.called.number, call->dest);
}
/* Encode the Global Call Reference (if present) */
if (call->gcr_present) {
msg = msgb_alloc(sizeof(mncc.gcr), "MNCC GCR");
if (msg == NULL || (rc = osmo_enc_gcr(msg, &call->gcr)) == 0)
LOGP(DMNCC, LOGL_ERROR, "MNCC leg(%u) failed to encode GCR\n", call->id);
else
memcpy(&mncc.gcr[0], msg->data, rc);
msgb_free(msg);
}
/*
* TODO/FIXME:
* - Determine/request channel based on offered audio codecs

View File

@ -26,7 +26,6 @@
#include <osmocom/core/linuxlist.h>
#include <osmocom/gsm/mncc.h>
#include <osmocom/gsm/gsm29205.h>
#include <stdint.h>
#include <netinet/in.h>
@ -124,6 +123,7 @@ struct gsm_call {
#define MNCC_F_CCCAP 0x0800
#define MNCC_F_KEYPAD 0x1000
#define MNCC_F_SIGNAL 0x2000
#define MNCC_F_GCR 0x4000
struct gsm_mncc {
/* context based information */
@ -160,7 +160,9 @@ struct gsm_mncc {
unsigned char lchan_type;
unsigned char lchan_mode;
struct osmo_gcr_parsed gcr;
/* Global Call Reference (encoded as per 3GPP TS 29.205) */
uint8_t gcr[16];
/* A buffer to contain SDP ('\0' terminated) */
char sdp[1024];