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.

Indicate presence of GCR using the MNCC_F_GCR flag.

Change-Id: I259b6d7e4cbe26159b9b496356fc7c1c27d54521
Fixes: I705c860e51637b4537cad65a330ecbaaca96dd5b
Related: OS#5164, OS#5282
This commit is contained in:
Vadim Yanitskiy 2021-10-27 17:05:55 +03:00 committed by fixeria
parent e0661105ac
commit c6921e5068
3 changed files with 34 additions and 17 deletions

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>
@ -125,6 +124,7 @@ 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 */
@ -161,7 +161,10 @@ 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];
};

View File

@ -320,12 +320,16 @@ static void cc_paging_cb(struct msc_a *msc_a, struct gsm_trans *trans)
trans->paging_request = NULL;
/* Get the GCR from the MO call leg (if any). */
if (!trans->cc.lcls) {
if (!trans->cc.lcls)
trans->cc.lcls = trans_lcls_compose(trans, true);
if (trans->cc.lcls) {
trans->cc.lcls->gcr = trans->cc.msg.gcr;
if (trans->cc.lcls && trans->cc.msg.fields & MNCC_F_GCR) {
int rc = osmo_dec_gcr(&trans->cc.lcls->gcr,
&trans->cc.msg.gcr[0],
sizeof(trans->cc.msg.gcr));
if (rc < 0)
LOG_TRANS(trans, LOGL_ERROR, "Failed to parse GCR\n");
else
trans->cc.lcls->gcr_available = true;
}
}
osmo_fsm_inst_dispatch(msc_a->c.fi, MSC_A_EV_TRANSACTION_ACCEPTED, trans);
@ -517,8 +521,18 @@ static int gsm48_cc_rx_setup(struct gsm_trans *trans, struct msgb *msg)
trans->cc.lcls = trans_lcls_compose(trans, true);
/* Pass the LCLS GCR on to the MT call leg via MNCC */
if (trans->cc.lcls)
setup.gcr = trans->cc.lcls->gcr;
if (trans->cc.lcls) {
struct msgb *gcr_msg = msgb_alloc(sizeof(setup.gcr), "MNCC GCR");
const struct osmo_gcr_parsed *gcr = &trans->cc.lcls->gcr;
int rc;
if (gcr_msg != NULL && (rc = osmo_enc_gcr(gcr_msg, gcr)) > 0) {
memcpy(&setup.gcr[0], gcr_msg->data, rc);
setup.fields |= MNCC_F_GCR;
} else
LOG_TRANS(trans, LOGL_ERROR, "Failed to encode GCR\n");
msgb_free(gcr_msg);
}
tlv_parse(&tp, &gsm48_att_tlvdef, gh->data, payload_len, 0, 0);
/* emergency setup is identified by msg_type */

View File

@ -1,15 +1,15 @@
test_sdp_termination()
struct gsm_mncc:
empty SDP: len=1872 sdplen=1024 sdp="\0" rc=0
empty SDP, shortest possible: len=849 sdplen=1 sdp="\0" rc=0
empty SDP, zero len: len=848 sdplen=0 sdp=- rc=-22
terminated SDP str: len=1872 sdplen=1024 sdp="Privacy is a desirable marketing option\0" rc=0
terminated SDP str, shortest possible: len=888 sdplen=40 sdp="Privacy is a desirable marketing option\0" rc=0
terminated SDP str, but len excludes nul: len=887 sdplen=39 sdp="Privacy is a desirable marketing option" rc=-22
terminated SDP str, but len too short: len=871 sdplen=23 sdp="Privacy is a desirable " rc=-22
len way too short: len=10 sdplen=-838 sdp=- rc=-22
len zero: len=0 sdplen=-848 sdp=- rc=-22
empty SDP: len=1876 sdplen=1026 sdp="\0" rc=0
empty SDP, shortest possible: len=851 sdplen=1 sdp="\0" rc=0
empty SDP, zero len: len=850 sdplen=0 sdp=- rc=-22
terminated SDP str: len=1876 sdplen=1026 sdp="Privacy is a desirable marketing option\0" rc=0
terminated SDP str, shortest possible: len=890 sdplen=40 sdp="Privacy is a desirable marketing option\0" rc=0
terminated SDP str, but len excludes nul: len=889 sdplen=39 sdp="Privacy is a desirable marketing option" rc=-22
terminated SDP str, but len too short: len=873 sdplen=23 sdp="Privacy is a desirable " rc=-22
len way too short: len=10 sdplen=-840 sdp=- rc=-22
len zero: len=0 sdplen=-850 sdp=- rc=-22
struct gsm_mncc_rtp:
empty SDP: len=1168 sdplen=1024 sdp="\0" rc=0