[sccp] Parse the error message and add a unit test for it.

3 files changed, 46 insertions, 1 deletions

diff --git a/openbsc/include/sccp/sccp_types.h b/openbsc/include/sccp/sccp_types.h
index 42fda96ae..22bd70f21 100644
--- a/openbsc/include/sccp/sccp_types.h
+++ b/openbsc/include/sccp/sccp_types.h
@@ -411,4 +411,10 @@ struct sccp_data_it {
 	u_int8_t			credit;
 } __attribute__((packed));
 
+struct sccp_proto_err {
+	u_int8_t			type;
+	struct sccp_source_reference	destination_local_reference;
+	u_int8_t			error_cause;
+};
+
 #endif
diff --git a/openbsc/src/sccp/sccp.c b/openbsc/src/sccp/sccp.c
index e0fd02e0e..d869bfaeb 100644
--- a/openbsc/src/sccp/sccp.c
+++ b/openbsc/src/sccp/sccp.c
@@ -490,6 +490,23 @@ static int _sccp_parse_it(struct msgb *msgb, struct sccp_parse_result *result)
 	return 0;
 }
 
+static int _sccp_parse_err(struct msgb *msgb, struct sccp_parse_result *result)
+{
+	static const u_int32_t header_size = sizeof(struct sccp_proto_err);
+
+	struct sccp_proto_err *err;
+
+	if (msgb_l2len(msgb) < header_size) {
+		LOGP(DSCCP, LOGL_ERROR, "msgb < header_size %u %u\n",
+		     msgb_l2len(msgb), header_size);
+		return -1;
+	}
+
+	err = (struct sccp_proto_err *) msgb->l2h;
+	result->data_len = 0;
+	result->destination_local_reference = &err->destination_local_reference;
+	return 0;
+}
 
 /*
  * Send UDT. Currently we have a fixed address...
@@ -1318,6 +1335,9 @@ int sccp_parse_header(struct msgb *msg, struct sccp_parse_result *result)
 	case SCCP_MSG_TYPE_IT:
 		return _sccp_parse_it(msg, result);
 		break;
+	case SCCP_MSG_TYPE_ERR:
+		return _sccp_parse_err(msg, result);
+		break;
 	};
 
 	LOGP(DSCCP, LOGL_ERROR, "Unimplemented MSG Type: 0x%x\n", type);
diff --git a/openbsc/tests/sccp/sccp_test.c b/openbsc/tests/sccp/sccp_test.c
index 0c2adc83f..31eb47f9f 100644
--- a/openbsc/tests/sccp/sccp_test.c
+++ b/openbsc/tests/sccp/sccp_test.c
@@ -264,6 +264,10 @@ static const u_int8_t it_test[] = {
 0x10, 0x01, 0x07, 
 0x94, 0x01, 0x04, 0x00, 0x02, 0x00, 0x00, 0x00 };
 
+static const u_int8_t proto_err[] = {
+0x0f, 0x0c, 0x04, 0x00, 0x00,
+};
+
 static const struct sccp_parse_header_result parse_result[] = {
 	{
 		.msg_type	= SCCP_MSG_TYPE_IT,
@@ -287,6 +291,21 @@ static const struct sccp_parse_header_result parse_result[] = {
 		.input		= it_test,
 		.input_len	= sizeof(it_test),
 	},
+	{
+		.msg_type	= SCCP_MSG_TYPE_ERR,
+		.wanted_len	= 0,
+		.src_ssn	= -1,
+		.dst_ssn	= -1,
+		.has_src_ref	= 0,
+		.has_dst_ref	= 1,
+		.dst_ref	= {
+			.octet1 = 0x0c,
+			.octet2 = 0x04,
+			.octet3 = 0x00,
+		},
+		.input		= proto_err,
+		.input_len	= sizeof(proto_err),
+	},
 };
 
 
@@ -777,7 +796,7 @@ static void test_sccp_parsing(void)
 
 		memset(&result, 0, sizeof(result));
 		if (sccp_parse_header(msg, &result) != 0) {
-			fprintf(stderr, "Failed to parse test: %d\n", current_test);
+			fprintf(stderr, "Failed to sccp parse test: %d\n", current_test);
 		} else {
 			if (parse_result[current_test].wanted_len != result.data_len) {
 				fprintf(stderr, "Unexpected data length.\n");