net: lwm2m: Only parse TLV from the first block

This was already implemented for firmware update packages.
For other opaque resources it failed to determine the target resource
id, which is now stored in the block_context.

Signed-off-by: Jan Buenker <jan.buenker@grandcentrix.net>

Author: jb-gcx

subsys/net/lib/lwm2m/lwm2m_object.h

@@ -414,6 +414,7 @@ struct lwm2m_block_context {
 	uint8_t token[8];
 	uint8_t tkl;
 	bool last_block : 1;
+	uint16_t res_id;
 };
 
 struct lwm2m_output_context {

subsys/net/lib/lwm2m/lwm2m_rw_oma_tlv.c

@@ -935,23 +935,53 @@ static int do_write_op_tlv_item(struct lwm2m_message *msg)
 	return ret;
 }
 
+static int write_tlv_resource(struct lwm2m_message *msg, struct oma_tlv *tlv)
+{
+	int ret;
+
+	if (msg->in.block_ctx) {
+		msg->in.block_ctx->res_id = tlv->id;
+	}
+
+	msg->path.res_id = tlv->id;
+	msg->path.level = 3U;
+	ret = do_write_op_tlv_item(msg);
+
+	/*
+	 * ignore errors for CREATE op
+	 * for OP_CREATE and BOOTSTRAP WRITE: errors on
+	 * optional resources are ignored (ENOTSUP)
+	 */
+	if (ret < 0 &&
+	    !((ret == -ENOTSUP) &&
+	      (msg->ctx->bootstrap_mode ||
+	       msg->operation == LWM2M_OP_CREATE))) {
+		return ret;
+	}
+
+	return 0;
+}
+
 int do_write_op_tlv(struct lwm2m_message *msg)
 {
 	struct lwm2m_engine_obj_inst *obj_inst = NULL;
 	size_t len;
 	struct oma_tlv tlv;
 	int ret;
 
-	/* In case of Firmware object Package resource go directly to the
+	/* In case of block transfer go directly to the
 	 * message processing - consecutive blocks will not carry the TLV
 	 * header.
 	 */
-	if (msg->in.block_ctx != NULL && msg->in.block_ctx->ctx.current > 0 &&
-	    msg->path.obj_id == 5 && msg->path.res_id == 0) {
+	if (msg->in.block_ctx != NULL && msg->in.block_ctx->ctx.current > 0) {
+		msg->path.res_id = msg->in.block_ctx->res_id;
+		msg->path.level = 3U;
 		ret = do_write_op_tlv_item(msg);
 		if (ret < 0) {
 			return ret;
 		}
+
+		return 0;
 	}
 
 	while (true) {
@@ -995,36 +1025,16 @@ int do_write_op_tlv(struct lwm2m_message *msg)
 					continue;
 				}
 
-				msg->path.res_id = tlv2.id;
-				msg->path.level = 3U;
-				ret = do_write_op_tlv_item(msg);
-				/*
-				 * ignore errors for CREATE op
-				 * for OP_CREATE and BOOTSTRAP WRITE: errors on
-				 * optional resources are ignored (ENOTSUP)
-				 */
-				if (ret < 0 &&
-				    !((ret == -ENOTSUP) &&
-				      (msg->ctx->bootstrap_mode ||
-				       msg->operation == LWM2M_OP_CREATE))) {
+				ret = write_tlv_resource(msg, &tlv2);
+				if (ret) {
 					return ret;
 				}
 
 				pos += len2;
 			}
 		} else if (tlv.type == OMA_TLV_TYPE_RESOURCE) {
-			msg->path.res_id = tlv.id;
-			msg->path.level = 3U;
-			ret = do_write_op_tlv_item(msg);
-			/*
-			 * ignore errors for CREATE op
-			 * for OP_CREATE and BOOTSTRAP WRITE: errors on optional
-			 * resources are ignored (ENOTSUP)
-			 */
-			if (ret < 0 &&
-			    !((ret == -ENOTSUP) &&
-			      (msg->ctx->bootstrap_mode ||
-			       msg->operation == LWM2M_OP_CREATE))) {
+			ret = write_tlv_resource(msg, &tlv);
+			if (ret) {
 				return ret;
 			}
 		} else {