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Sergey.Kostanbaev sergey.kostanbaev at gmail.comFrom: Sergey Kostanbaev <sergey.kostanbaev at gmail.com>
Use new ss_request structure to support long messages and handle FACILITY
message type to support USSD menus.
---
openbsc/include/openbsc/gsm_04_80.h | 11 ++--
openbsc/src/libmsc/gsm_04_80.c | 119 +++++++++++++++++++++++++++---------
openbsc/src/libmsc/ussd.c | 44 ++++++++-----
3 files changed, 128 insertions(+), 46 deletions(-)
diff --git a/openbsc/include/openbsc/gsm_04_80.h b/openbsc/include/openbsc/gsm_04_80.h
index 0a60652..08f974f 100644
--- a/openbsc/include/openbsc/gsm_04_80.h
+++ b/openbsc/include/openbsc/gsm_04_80.h
@@ -7,12 +7,15 @@
struct gsm_subscriber_connection;
+int gsm0480_send_ussd(struct gsm_subscriber_connection *conn,
+ struct ss_request *req);
+
int gsm0480_send_ussd_response(struct gsm_subscriber_connection *conn,
- const struct msgb *in_msg, const char* response_text,
- const struct ussd_request *req);
+ const char *resp_string,
+ const struct ss_request *req);
+
int gsm0480_send_ussd_reject(struct gsm_subscriber_connection *conn,
- const struct msgb *msg,
- const struct ussd_request *request);
+ const struct ss_request *request);
int gsm0480_send_ussdNotify(struct gsm_subscriber_connection *conn, int level, const char *text);
int gsm0480_send_releaseComplete(struct gsm_subscriber_connection *conn);
diff --git a/openbsc/src/libmsc/gsm_04_80.c b/openbsc/src/libmsc/gsm_04_80.c
index b30f9ee..4585202 100644
--- a/openbsc/src/libmsc/gsm_04_80.c
+++ b/openbsc/src/libmsc/gsm_04_80.c
@@ -39,6 +39,22 @@
#include <osmocom/core/msgb.h>
#include <osmocom/gsm/tlv.h>
+/* This function can handle ASN1 length up to 255 which is enough for USSD */
+static inline unsigned char *msgb_wrap_with_ASN1_TL(struct msgb *msgb, uint8_t tag)
+{
+ uint16_t origlen = msgb->len;
+ uint8_t *data = msgb_push(msgb, (origlen > 0x7f) ? 3 : 2);
+ data[0] = tag;
+ if (origlen > 0x7f) {
+ data[1] = 0x81;
+ data[2] = origlen;
+ } else {
+ data[1] = origlen;
+ }
+ return data;
+}
+
+
static inline unsigned char *msgb_wrap_with_TL(struct msgb *msgb, uint8_t tag)
{
uint8_t *data = msgb_push(msgb, 2);
@@ -59,59 +75,106 @@ static inline unsigned char *msgb_push_TLV1(struct msgb *msgb, uint8_t tag,
return data;
}
+static inline unsigned char *msgb_wrap_with_L(struct msgb *msgb)
+{
+ uint8_t *data = msgb_push(msgb, 1);
+
+ data[0] = msgb->len - 1;
+ return data;
+}
/* Send response to a mobile-originated ProcessUnstructuredSS-Request */
int gsm0480_send_ussd_response(struct gsm_subscriber_connection *conn,
- const struct msgb *in_msg, const char *response_text,
- const struct ussd_request *req)
+ const char *resp_string,
+ const struct ss_request* req)
+{
+ struct ss_request rss;
+ int response_len;
+
+ memset(&rss, 0, sizeof(rss));
+
+ gsm_7bit_encode_n_ussd(rss.ussd_text, MAX_LEN_USSD_STRING, resp_string, &response_len);
+ rss.ussd_text_len = response_len;
+ rss.ussd_text_language = 0x0f;
+
+ rss.transaction_id = req->transaction_id;
+ rss.message_type = GSM0480_MTYPE_RELEASE_COMPLETE;
+ rss.component_type = GSM0480_CTYPE_RETURN_RESULT;
+ rss.invoke_id = req->invoke_id;
+ rss.opcode = GSM0480_OP_CODE_PROCESS_USS_REQ;
+
+ return gsm0480_send_ussd(conn, &rss);
+}
+
+/* Compose universial SS packet except Reject opcodes */
+int gsm0480_send_ussd(struct gsm_subscriber_connection *conn,
+ struct ss_request* req)
{
struct msgb *msg = gsm48_msgb_alloc();
struct gsm48_hdr *gh;
uint8_t *ptr8;
- int response_len;
/* First put the payload text into the message */
ptr8 = msgb_put(msg, 0);
- gsm_7bit_encode_n_ussd(ptr8, msgb_tailroom(msg), response_text, &response_len);
- msgb_put(msg, response_len);
+
+ memcpy(ptr8, req->ussd_text, req->ussd_text_len);
+ msgb_put(msg, req->ussd_text_len);
/* Then wrap it as an Octet String */
- msgb_wrap_with_TL(msg, ASN1_OCTET_STRING_TAG);
+ msgb_wrap_with_ASN1_TL(msg, ASN1_OCTET_STRING_TAG);
/* Pre-pend the DCS octet string */
- msgb_push_TLV1(msg, ASN1_OCTET_STRING_TAG, 0x0F);
+ msgb_push_TLV1(msg, ASN1_OCTET_STRING_TAG, req->ussd_text_language);
/* 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, req->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);
+ msgb_wrap_with_ASN1_TL(msg, GSM_0480_SEQUENCE_TAG);
+
+ if (req->component_type == GSM0480_CTYPE_RETURN_RESULT) {
+ /* Pre-pend the operation code */
+ msgb_push_TLV1(msg, GSM0480_OPERATION_CODE, req->opcode);
+
+ /* Wrap the operation code and IA5 string as a sequence */
+ msgb_wrap_with_ASN1_TL(msg, GSM_0480_SEQUENCE_TAG);
+
+ /* Pre-pend the invoke ID */
+ msgb_push_TLV1(msg, GSM0480_COMPIDTAG_INVOKE_ID, req->invoke_id);
+ } else if (req->component_type == GSM0480_CTYPE_INVOKE) {
+ /* Pre-pend the operation code */
+ msgb_push_TLV1(msg, GSM0480_OPERATION_CODE, req->opcode);
+
+ /* Pre-pend the invoke ID */
+ msgb_push_TLV1(msg, GSM0480_COMPIDTAG_INVOKE_ID, req->invoke_id);
+ } else {
+ abort();
+ }
+
+ /* Wrap this up as an Invoke or a Return Result component */
+ msgb_wrap_with_ASN1_TL(msg, req->component_type);
+
+ if (req->message_type == GSM0480_MTYPE_REGISTER ||
+ req->message_type == GSM0480_MTYPE_RELEASE_COMPLETE) {
+ /* Wrap the component in a Facility message, it's not ASN1 */
+ msgb_wrap_with_TL(msg, GSM0480_IE_FACILITY);
+ } else if (req->message_type == GSM0480_MTYPE_FACILITY) {
+ /* For GSM0480_MTYPE_FACILITY it's LV not TLV */
+ msgb_wrap_with_L(msg);
+ } else {
+ abort();
+ }
/* And finally pre-pend the L3 header */
gh = (struct gsm48_hdr *) msgb_push(msg, sizeof(*gh));
gh->proto_discr = GSM48_PDISC_NC_SS | req->transaction_id
| (1<<7); /* TI direction = 1 */
- gh->msg_type = GSM0480_MTYPE_RELEASE_COMPLETE;
+ gh->msg_type = req->message_type;
+
+ DEBUGP(DSS, "Sending USSD to mobile: %s\n", msgb_hexdump(msg));
return gsm0808_submit_dtap(conn, msg, 0, 0);
}
int gsm0480_send_ussd_reject(struct gsm_subscriber_connection *conn,
- const struct msgb *in_msg,
- const struct ussd_request *req)
+ const struct ss_request *req)
{
struct msgb *msg = gsm48_msgb_alloc();
struct gsm48_hdr *gh;
@@ -124,7 +187,7 @@ int gsm0480_send_ussd_reject(struct gsm_subscriber_connection *conn,
msgb_push_TLV1(msg, GSM0480_COMPIDTAG_INVOKE_ID, req->invoke_id);
/* Wrap this up as a Reject component */
- msgb_wrap_with_TL(msg, GSM0480_CTYPE_REJECT);
+ msgb_wrap_with_ASN1_TL(msg, GSM0480_CTYPE_REJECT);
/* Wrap the component in a Facility message */
msgb_wrap_with_TL(msg, GSM0480_IE_FACILITY);
diff --git a/openbsc/src/libmsc/ussd.c b/openbsc/src/libmsc/ussd.c
index 7f01eae..f0426c4 100644
--- a/openbsc/src/libmsc/ussd.c
+++ b/openbsc/src/libmsc/ussd.c
@@ -33,41 +33,57 @@
#include <openbsc/gsm_subscriber.h>
#include <openbsc/debug.h>
#include <openbsc/osmo_msc.h>
+#include <openbsc/ussd.h>
+#include <osmocom/gsm/gsm_utils.h>
+#include <osmocom/gsm/gsm0480.h>
/* Declarations of USSD strings to be recognised */
const char USSD_TEXT_OWN_NUMBER[] = "*#100#";
/* Forward declarations of network-specific handler functions */
-static int send_own_number(struct gsm_subscriber_connection *conn, const struct msgb *msg, const struct ussd_request *req);
+static int send_own_number(struct gsm_subscriber_connection *conn, const struct ss_request *req);
/* Entrypoint - handler function common to all mobile-originated USSDs */
int handle_rcv_ussd(struct gsm_subscriber_connection *conn, struct msgb *msg)
{
int rc;
- struct ussd_request req;
+ struct ss_request req;
+ char request_string[MAX_LEN_USSD_STRING + 1];
struct gsm48_hdr *gh;
memset(&req, 0, sizeof(req));
gh = msgb_l3(msg);
- rc = gsm0480_decode_ussd_request(gh, msgb_l3len(msg), &req);
+ rc = gsm0480_decode_ss_request(gh, msgb_l3len(msg), &req);
if (!rc) {
- DEBUGP(DMM, "Unhandled SS\n");
- rc = gsm0480_send_ussd_reject(conn, msg, &req);
+ DEBUGP(DSS, "Unhandled SS\n");
+ rc = gsm0480_send_ussd_reject(conn, &req);
msc_release_connection(conn);
return rc;
}
- /* Release-Complete */
- if (req.text[0] == '\0')
+ if (req.message_type == GSM0480_MTYPE_RELEASE_COMPLETE)
return 0;
- if (!strcmp(USSD_TEXT_OWN_NUMBER, (const char *)req.text)) {
- DEBUGP(DMM, "USSD: Own number requested\n");
- rc = send_own_number(conn, msg, &req);
+ if (req.message_type != GSM0480_MTYPE_REGISTER ||
+ req.component_type != GSM0480_CTYPE_INVOKE ||
+ req.opcode != GSM0480_OP_CODE_PROCESS_USS_REQ ||
+ req.ussd_text_language != 0x0f)
+ {
+ DEBUGP(DSS, "Unexpected SS\n");
+ rc = gsm0480_send_ussd_reject(conn, &req);
+ msc_release_connection(conn);
+ return rc;
+ }
+
+ gsm_7bit_decode_n_ussd(request_string, MAX_LEN_USSD_STRING, req.ussd_text, req.ussd_text_len);
+
+ if (!strcmp(USSD_TEXT_OWN_NUMBER, (const char *)request_string)) {
+ DEBUGP(DSS, "USSD: Own number requested\n");
+ rc = send_own_number(conn, &req);
} else {
- DEBUGP(DMM, "Unhandled USSD %s\n", req.text);
- rc = gsm0480_send_ussd_reject(conn, msg, &req);
+ DEBUGP(DSS, "Unhandled USSD %s\n", request_string);
+ rc = gsm0480_send_ussd_reject(conn, &req);
}
/* check if we can release it */
@@ -76,12 +92,12 @@ int handle_rcv_ussd(struct gsm_subscriber_connection *conn, struct msgb *msg)
}
/* A network-specific handler function */
-static int send_own_number(struct gsm_subscriber_connection *conn, const struct msgb *msg, const struct ussd_request *req)
+static int send_own_number(struct gsm_subscriber_connection *conn, const struct ss_request *req)
{
char *own_number = conn->subscr->extension;
char response_string[GSM_EXTENSION_LENGTH + 20];
/* Need trailing CR as EOT character */
snprintf(response_string, sizeof(response_string), "Your extension is %s\r", own_number);
- return gsm0480_send_ussd_response(conn, msg, response_string, req);
+ return gsm0480_send_ussd_response(conn, response_string, req);
}
--
1.9.1