feat(inputs.win_wmi): Allow to invoke methods

plugins/inputs/win_wmi/README.md

@@ -40,43 +40,114 @@ to use them.
   # username = ""
   # password = ""
 
+  ## WMI query to execute, multiple methods are possible
   [[inputs.win_wmi.query]]
-    # a string representing the WMI namespace to be queried
+    ## Namespace, class and a list of properties to use in the WMI query
     namespace = "root\\cimv2"
-    # a string representing the WMI class to be queried
     class_name = "Win32_Volume"
-    # an array of strings representing the properties of the WMI class to be queried
     properties = ["Name", "Capacity", "FreeSpace"]
-    # a string specifying a WHERE clause to use as a filter for the WQL
-    filter = 'NOT Name LIKE "\\\\?\\%"'
-    # WMI class properties which should be considered tags instead of fields
-    tag_properties = ["Name"]
+    ## Optional WHERE clause for the WQL query
+    # filter = 'NOT Name LIKE "\\\\?\\%"'
+    ## Returned properties to use as tags instead of fields
+    # tag_properties = ["Name"]
+
+  # ## WMI method to invoke, multiple methods are possible
+  # [[inputs.win_wmi.method]]
+  #   ## WMI namespace, class and method to use
+  #   namespace = 'root\default'
+  #   class_name = "StdRegProv"
+  #   method = "GetStringValue"
+  #   ## Returned WMI method values to use as tags instead of fields
+  #   # tag_properties = ["ReturnValue"]
+  #   ## Named arguments for the method call
+  #   [inputs.win_wmi.method.arguments]
+  #     hDefKey = '2147483650'
+  #     sSubKeyName = 'Software\Microsoft\windows NT\CurrentVersion'
+  #     sValueName = 'ProductName'
+  #   ## Mapping of the name of the returned property to a field-name
+  #   [inputs.win_wmi.method.fields]
+  #       sValue = "product_name"
 ```
 
-### namespace
+### Remote execution
 
-A string representing the WMI namespace to be queried. For example,
-`root\\cimv2`.
+This plugin allows to execute queries and methods on a remote host. To do so,
+you need to provide the `host` as a hostname or IP-address as well as the
+credentials to execute the query or method as.
 
-### class_name
+Please note, the remote machine must be configured to allow remote execution and
+the user needs to have sufficient permission to execute the query or method!
+Check the [Microsoft guide][remotedoc] for how to do this and test the
+connection with the `Get-WmiObject` method first.
 
-A string representing the WMI class to be queried. For example,
-`Win32_Processor`.
+[remotedoc]:  https://learn.microsoft.com/en-us/windows/win32/wmisdk/connecting-to-wmi-on-a-remote-computer#configuring-a-computer-for-a-remote-connection
 
-### properties
+### Query settings
 
-An array of strings representing the properties of the WMI class to be queried.
+To issue a query you need to provide the `namespace` (e.g. `root\cimv2`) and the
+`class_name` (e.g. `Win32_Processor`) for the WMI query. Furthermore, you need
+to define which `properties` to output. An asterix (`*`) will output all values
+provided by the query.
 
-### filter
+The `filter` setting specifies a WHERE clause passed to the query in the
+WMI Query Language (WQL). See [WHERE Clause][WHERE] for more information.
 
-A string specifying a WHERE clause to use as a filter for the WMI Query
-Language (WQL). See [WHERE Clause][WHERE] for more information.
+The `tag_properties` allows to provide a list of returned properties that should
+be provided as tags instead of fields in the metric.
 
 [WHERE]: https://learn.microsoft.com/en-us/windows/win32/wmisdk/where-clause?source=recommendations
 
-### tag_properties
+As an example
+
+```toml
+[[inputs.win_wmi]]
+  [[inputs.win_wmi.query]]
+    namespace = "root\\cimv2"
+    class_name = "Win32_Processor"
+    properties = ["Name"]
+```
+
+corresponds to executing
+
+```powershell
+Get-WmiObject -Namespace "root\cimv2" -Class "Win32_Processor" -Property "Name"
+```
+
+### Method settings
 
-Properties which should be considered tags instead of fields.
+To invoke a method you need to provide the `namespace` (e.g. `root\default`),
+the `class_name` (e.g. `StdRegProv`) and the `method` name
+(e.g. `GetStringValue`)for the method to invoke. Furthermore, you may need to
+provide `arguments` as key-value pair(s) to the method. The number and type of
+arguments depends on the method specified above.
+
+Check the [WMI reference][wmireferenc] for available methods and their
+arguments.
+
+The `tag_properties` allows to provide a list of returned properties that should
+be provided as tags instead of fields in the metric.
+
+[wmireferenc]: https://learn.microsoft.com/en-us/windows/win32/wmisdk/wmi-reference
+
+As an example
+
+```toml
+[[inputs.win_wmi]]
+  [[inputs.win_wmi.method]]
+    namespace = 'root\default'
+    class_name = "StdRegProv"
+    method = "GetStringValue"
+    [inputs.win_wmi.method.arguments]
+      hDefKey = '2147483650'
+      sSubKeyName = 'Software\Microsoft\windows NT\CurrentVersion'
+      sValueName = 'ProductName'
+```
+
+corresponds to executing
+
+```powershell
+Invoke-WmiMethod -Namespace "root\default" -Class "StdRegProv" -Name "GetStringValue" @(2147483650,"Software\Microsoft\windows NT\CurrentVersion", "ProductName")
+```
 
 ## Metrics
 

plugins/inputs/win_wmi/method.go

@@ -0,0 +1,228 @@
+//go:build windows
+
+package win_wmi
+
+import (
+	"errors"
+	"fmt"
+	"runtime"
+
+	"github.com/go-ole/go-ole"
+	"github.com/go-ole/go-ole/oleutil"
+	"github.com/influxdata/telegraf"
+	"github.com/influxdata/telegraf/config"
+	"github.com/influxdata/telegraf/filter"
+	"github.com/influxdata/telegraf/internal"
+)
+
+// Method struct
+type Method struct {
+	Namespace            string                 `toml:"namespace"`
+	ClassName            string                 `toml:"class_name"`
+	Method               string                 `toml:"method"`
+	Arguments            map[string]interface{} `toml:"arguments"`
+	FieldMapping         map[string]string      `toml:"fields"`
+	Filter               string                 `toml:"filter"`
+	TagPropertiesInclude []string               `toml:"tag_properties"`
+
+	host             string
+	connectionParams []interface{}
+	tagFilter        filter.Filter
+}
+
+func (m *Method) prepare(host string, username, password config.Secret) error {
+	// Compile the filter
+	f, err := filter.Compile(m.TagPropertiesInclude)
+	if err != nil {
+		return fmt.Errorf("compiling tag-filter failed: %w", err)
+	}
+	m.tagFilter = f
+
+	// Setup the connection parameters
+	m.host = host
+	if m.host != "" {
+		m.connectionParams = append(m.connectionParams, m.host)
+	} else {
+		m.connectionParams = append(m.connectionParams, nil)
+	}
+	m.connectionParams = append(m.connectionParams, m.Namespace)
+	if !username.Empty() {
+		u, err := username.Get()
+		if err != nil {
+			return fmt.Errorf("getting username secret failed: %w", err)
+		}
+		m.connectionParams = append(m.connectionParams, u.String())
+		username.Destroy()
+	}
+	if !password.Empty() {
+		p, err := password.Get()
+		if err != nil {
+			return fmt.Errorf("getting password secret failed: %w", err)
+		}
+		m.connectionParams = append(m.connectionParams, p.String())
+		password.Destroy()
+	}
+
+	return nil
+}
+
+func (m *Method) execute(acc telegraf.Accumulator) error {
+	// The only way to run WMI queries in parallel while being thread-safe is to
+	// ensure the CoInitialize[Ex]() call is bound to its current OS thread.
+	// Otherwise, attempting to initialize and run parallel queries across
+	// goroutines will result in protected memory errors.
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
+	// Init the COM client
+	if err := ole.CoInitializeEx(0, ole.COINIT_MULTITHREADED); err != nil {
+		var oleCode *ole.OleError
+		if errors.As(err, &oleCode) && oleCode.Code() != ole.S_OK && oleCode.Code() != sFalse {
+			return err
+		}
+	}
+	defer ole.CoUninitialize()
+
+	// Initialize the WMI service
+	locator, err := oleutil.CreateObject("WbemScripting.SWbemLocator")
+	if err != nil {
+		return err
+	}
+	if locator == nil {
+		return errors.New("failed to create WbemScripting.SWbemLocator, maybe WMI is broken")
+	}
+	defer locator.Release()
+	wmi, err := locator.QueryInterface(ole.IID_IDispatch)
+	if err != nil {
+		return fmt.Errorf("failed to query interface: %w", err)
+	}
+	defer wmi.Release()
+
+	serviceRaw, err := oleutil.CallMethod(wmi, "ConnectServer", m.connectionParams...)
+	if err != nil {
+		return fmt.Errorf("failed calling method ConnectServer: %w", err)
+	}
+	service := serviceRaw.ToIDispatch()
+	defer serviceRaw.Clear()
+
+	// Get the specified class-method
+	classRaw, err := oleutil.CallMethod(service, "Get", m.ClassName)
+	if err != nil {
+		return fmt.Errorf("failed to get class %s: %w", m.ClassName, err)
+	}
+	class := classRaw.ToIDispatch()
+	defer classRaw.Clear()
+
+	classMethodsRaw, err := class.GetProperty("Methods_")
+	if err != nil {
+		return fmt.Errorf("failed to call method %s: %w", m.Method, err)
+	}
+	classMethods := classMethodsRaw.ToIDispatch()
+	defer classMethodsRaw.Clear()
+
+	methodRaw, err := classMethods.CallMethod("Item", m.Method)
+	if err != nil {
+		return fmt.Errorf("failed to call method %s: %w", m.Method, err)
+	}
+	method := methodRaw.ToIDispatch()
+	defer methodRaw.Clear()
+
+	// Fill the input parameters of the method
+	inputParamsRaw, err := oleutil.GetProperty(method, "InParameters")
+	if err != nil {
+		return fmt.Errorf("failed to get input parameters for %s: %w", m.Method, err)
+	}
+	inputParams := inputParamsRaw.ToIDispatch()
+	defer inputParamsRaw.Clear()
+	for k, v := range m.Arguments {
+		if _, err := inputParams.PutProperty(k, v); err != nil {
+			return fmt.Errorf("setting param %q for method %q failed: %w", k, m.Method, err)
+		}
+	}
+
+	// Get the output parameters of the method
+	outputParamsRaw, err := oleutil.GetProperty(method, "OutParameters")
+	if err != nil {
+		return fmt.Errorf("failed to get output parameters for %s: %w", m.Method, err)
+	}
+	outputParams := outputParamsRaw.ToIDispatch()
+	defer outputParamsRaw.Clear()
+
+	// Execute the method
+	outputRaw, err := service.CallMethod("ExecMethod", "StdRegProv", m.Method, inputParamsRaw)
+	if err != nil {
+		return fmt.Errorf("failed to execute method %s: %w", m.Method, err)
+	}
+	output := outputRaw.ToIDispatch()
+	defer outputRaw.Clear()
+
+	outputPropertiesRaw, err := oleutil.GetProperty(outputParams, "Properties_")
+	if err != nil {
+		return fmt.Errorf("failed to get output properties for method %s: %w", m.Method, err)
+	}
+	outputProperties := outputPropertiesRaw.ToIDispatch()
+	defer outputPropertiesRaw.Clear()
+
+	// Convert the results to fields and tags
+	tags, fields := map[string]string{}, map[string]interface{}{}
+
+	// Add a source tag if we use remote queries
+	if m.host != "" {
+		tags["source"] = m.host
+	}
+
+	err = oleutil.ForEach(outputProperties, func(p *ole.VARIANT) error {
+		// Name of the returned result item
+		nameProperty, err := p.ToIDispatch().GetProperty("Name")
+		if err != nil {
+			return errors.New("cannot get output property name")
+		}
+		name := nameProperty.ToString()
+		defer nameProperty.Clear()
+
+		// Value of the returned result item
+		property, err := output.GetProperty(name)
+		if err != nil {
+			return fmt.Errorf("failed to get value for output property %s: %w", name, err)
+		}
+
+		// Map the fieldname if provided
+		if n, found := m.FieldMapping[name]; found {
+			name = n
+		}
+
+		// We might get either scalar values or an array of values...
+		if value := property.Value(); value != nil {
+			if m.tagFilter != nil && m.tagFilter.Match(name) {
+				if s, err := internal.ToString(value); err == nil && s != "" {
+					tags[name] = s
+				}
+			} else {
+				fields[name] = value
+			}
+			return nil
+		}
+		if array := property.ToArray(); array != nil {
+			if m.tagFilter != nil && m.tagFilter.Match(name) {
+				for i, v := range array.ToValueArray() {
+					if s, err := internal.ToString(v); err == nil && s != "" {
+						tags[fmt.Sprintf("%s_%d", name, i)] = s
+					}
+				}
+			} else {
+				for i, v := range array.ToValueArray() {
+					fields[fmt.Sprintf("%s_%d", name, i)] = v
+				}
+			}
+			return nil
+		}
+		return fmt.Errorf("cannot handle property %q with value %v", name, property)
+	})
+	if err != nil {
+		return fmt.Errorf("cannot iterate the output properties: %w", err)
+	}
+
+	acc.AddFields(m.ClassName, fields, tags)
+
+	return nil
+}

plugins/inputs/win_wmi/query.go

@@ -39,6 +39,7 @@ func (q *Query) prepare(host string, username, password config.Secret) error {
 	}
 	q.tagFilter = f
 
+	// Setup the connection parameters
 	q.host = host
 	if q.host != "" {
 		q.connectionParams = append(q.connectionParams, q.host)