gsm0480: Add method create own number response

diff --git a/include/osmocore/gsm0480.h b/include/osmocore/gsm0480.h
index 94ac717..b504332 100644 (file)
--- a/include/osmocore/gsm0480.h
+++ b/include/osmocore/gsm0480.h
@@ -16,6 +16,7 @@ struct ussd_request {
 int gsm0480_decode_ussd_request(const struct gsm48_hdr *hdr, uint16_t len,
                                struct ussd_request *request);
 
+struct msgb *gsm0480_create_ussd_resp(uint8_t invoke_id, uint8_t trans_id, const char *text);
 struct msgb *gsm0480_create_unstructuredSS_Notify(int alertPattern, const char *text);
 struct msgb *gsm0480_create_notifySS(const char *text);
 

diff --git a/src/gsm0480.c b/src/gsm0480.c
index b4ba830..b6b345c 100644 (file)
--- a/src/gsm0480.c
+++ b/src/gsm0480.c
@@ -409,3 +409,53 @@ static int parse_process_uss_req(const uint8_t *uss_req_data, uint16_t length,
        }
        return rc;
 }
+
+struct msgb *gsm0480_create_ussd_resp(uint8_t invoke_id, uint8_t trans_id, const char *text)
+{
+       struct msgb *msg;
+       struct gsm48_hdr *gh;
+       uint8_t *ptr8;
+       int response_len;
+
+       msg = msgb_alloc_headroom(1024, 128, "GSM 04.80");
+       if (!msg)
+               return NULL;
+
+       /* First put the payload text into the message */
+       ptr8 = msgb_put(msg, 0);
+       response_len = gsm_7bit_encode(ptr8, text);
+       msgb_put(msg, response_len);
+
+       /* Then wrap it as an Octet String */
+       msgb_wrap_with_TL(msg, ASN1_OCTET_STRING_TAG);
+
+       /* Pre-pend the DCS octet string */
+       msgb_push_TLV1(msg, ASN1_OCTET_STRING_TAG, 0x0F);
+
+       /* Then wrap these as a Sequence */
+       msgb_wrap_with_TL(msg, GSM_0480_SEQUENCE_TAG);
+
+       /* Pre-pend the operation code */
+       msgb_push_TLV1(msg, GSM0480_OPERATION_CODE,
+                       GSM0480_OP_CODE_PROCESS_USS_REQ);
+
+       /* Wrap the operation code and IA5 string as a sequence */
+       msgb_wrap_with_TL(msg, GSM_0480_SEQUENCE_TAG);
+
+       /* Pre-pend the invoke ID */
+       msgb_push_TLV1(msg, GSM0480_COMPIDTAG_INVOKE_ID, invoke_id);
+
+       /* Wrap this up as a Return Result component */
+       msgb_wrap_with_TL(msg, GSM0480_CTYPE_RETURN_RESULT);
+
+       /* Wrap the component in a Facility message */
+       msgb_wrap_with_TL(msg, GSM0480_IE_FACILITY);
+
+       /* And finally pre-pend the L3 header */
+       gh = (struct gsm48_hdr *) msgb_push(msg, sizeof(*gh));
+       gh->proto_discr = GSM48_PDISC_NC_SS | trans_id
+                                       | (1<<7);  /* TI direction = 1 */
+       gh->msg_type = GSM0480_MTYPE_RELEASE_COMPLETE;
+
+       return msg;
+}