CBProcess Class

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The CBProcess class enables applications to intercept process manager requests.

Syntax

class cbfsfilter.CBProcess

Remarks

The CBProcess class gives applications the ability to monitor and (in some cases) control process- and thread-related requests. Because the CBProcess API is far less complex than other classs' APIs, it uses simple filter rules; please refer to the File and Registry Filter Rules topic for more information.

To learn more about the class's capabilities, please refer to the product's General Information topics.

Getting Started

  1. If the class's system driver has not been installed yet, call the install method to do so. This needs to be done only once.
    • In production, the driver can be installed (or updated) ahead of time by the application's installation script using the Installer DLL. Please refer to the Driver Installation topic for more information.
  2. Call the initialize method to initialize the CBProcess class. This must be done each time the application starts.
  3. Add one or more filter rules using methods like add_filtered_process_by_id and add_filtered_process_by_name. (Rules also can be added or removed after the filter is started.)
  4. Call the start_filter method to start filtering process manager requests.
  5. When finished, call the stop_filter method to stop filtering process manager requests.
  6. To uninstall the class's system driver, call the uninstall method. This should not be done as part of the driver upgrade process.
    • In production, the driver can be uninstalled by the application's uninstallation script using the Installer DLL. Please refer to the Driver Installation topic for more information.

Property List

The following is the full list of the properties of the class with short descriptions. Click on the links for further details.

activeThis property notes whether the class is active and processing requests.
altitudeThis property specifies the altitude that the class's system driver should use.
running_process_countThe number of records in the RunningProcess arrays.
running_process_command_lineThis property reflects the command-line arguments of the process.
running_process_process_idThis property reflects the process Id (PID).
running_process_process_nameThis property reflects the name of the process.
serialize_eventsWhether events should be fired on a single worker thread, or many.
strict_altitudeThis property specifies how to behave if the specified altitude is already in use.
tagThis property stores application-defined data specific to a particular instance of the class.
track_command_lineThis property specifies whether the driver should store information about processes' command-line arguments.

Method List

The following is the full list of the methods of the class with short descriptions. Click on the links for further details.

add_filtered_process_by_idThis method adds a process, by process ID (PID), to the list of filtered processes.
add_filtered_process_by_nameThis method adds a process, by name, to the list of filtered processes.
add_ignored_process_by_idThis method adds a process, by process ID (PID), to the list of ignored processes.
add_ignored_process_by_nameThis method adds a process, by name, to the list of ignored processes.
close_running_processes_snapshotThis method closes the previously created snapshot of running processes.
configSets or retrieves a configuration setting.
create_running_processes_snapshotThis method creates a snapshot of running processes.
get_driver_statusThis method retrieves the status of the class's system driver.
get_driver_versionThis method retrieves the version of the class's system driver.
get_originator_tokenThis method retrieves the security token associated with the process that initiated the operation.
get_process_nameThis method retrieves the name of the process associated with the specified process ID (PID).
initializeThis method initializes the class.
installThis method installs (or upgrades) the class's system driver.
remove_filtered_process_by_idThis method removes a process, by process ID (PID), from the list of filtered processes.
remove_filtered_process_by_nameThis method removes a process, by name, from the list of filtered processes.
remove_ignored_process_by_idThis method removes a process, by process ID (PID), from the list of ignored processes.
remove_ignored_process_by_nameThis method removes a process, by name, from the list of ignored processes.
reset_timeoutThis method resets the timeout duration for the current event handler.
shutdown_systemShuts down or reboots the operating system.
start_filterThis method starts the filtering process and thread operations.
stop_filterThis method stops the filtering process and thread operations.
uninstallThis method uninstalls the class's system driver.

Event List

The following is the full list of the events fired by the class with short descriptions. Click on the links for further details.

on_errorThis event fires if an unhandled error occurs during an event.
on_process_creationThis event fires when a process is being created.
on_process_handle_operationThis event fires when a process handle is being created or duplicated.
on_process_terminationThis event fires when a process is being terminated.
on_thread_creationThis event fires when a thread is being created.
on_thread_handle_operationThis event fires when a thread handle is being created or duplicated.
on_thread_terminationThis event fires when a thread is being terminated.
on_worker_thread_creationFires just after a new worker thread is created.
on_worker_thread_terminationFires just before a worker thread is terminated.

Config Settings

The following is a list of config settings for the class with short descriptions. Click on the links for further details.

EventsToFireThe types of events that the instance must fire.
FilterOwnRequestsWhether the class's system driver should filter requests made by the application itself.
LoggingEnabledWhether extended logging is enabled.
MaxWorkerThreadCountThe maximum number of worker threads to use to fire events.
MinWorkerThreadCountThe minimum number of worker threads to use to fire events.
WorkerInitialStackSizeThe initial stack size to create worker threads with.
BuildInfoInformation about the product's build.
LicenseInfoInformation about the current license.

active Property

This property notes whether the class is active and processing requests.

Syntax

def get_active() -> bool: ...

active = property(get_active, None)

Default Value

FALSE

Remarks

This property reflects whether the class is active and currently processing requests. It will be True after the filter has been attached successfully via a call to start_filter.

This property is read-only.

altitude Property

This property specifies the altitude that the class's system driver should use.

Syntax

def get_altitude() -> str: ...
def set_altitude(value: str) -> None: ...

altitude = property(get_altitude, set_altitude)

Default Value

"400055"

Remarks

This property specifies the altitude that the class's system driver should use. A driver's altitude determines its absolute position in the stack of filter drivers; drivers with higher altitudes are attached toward the top of the stack, closer to the user mode, which allows them to process requests earlier.

Microsoft's documentation is unclear about how altitudes should be chosen for process manager filter drivers; please refer to the Driver Altitudes topic for more information. The default value of this property is 400055 (which is not registered with Microsoft), but applications can likely choose any value they desire. If the specified altitude is already in use by another driver, the class's driver will behave in the manner specified by the strict_altitude property.

running_process_count Property

The number of records in the RunningProcess arrays.

Syntax

def get_running_process_count() -> int: ...

running_process_count = property(get_running_process_count, None)

Default Value

0

Remarks

This property controls the size of the following arrays:

The array indices start at 0 and end at running_process_count - 1.

This property is read-only.

running_process_command_line Property

This property reflects the command-line arguments of the process.

Syntax

def get_running_process_command_line(running_process_index: int) -> str: ...

Default Value

""

Remarks

This property reflects the command-line arguments of the process.

This property reflects the command-line arguments, with which the process has been started.

By default, the driver does not store command-line arguments and this property is empty. To enable collection and retrieval of the command-line arguments, set the track_command_line property to True.

The running_process_index parameter specifies the index of the item in the array. The size of the array is controlled by the running_process_count property.

This property is read-only.

running_process_process_id Property

This property reflects the process Id (PID).

Syntax

def get_running_process_process_id(running_process_index: int) -> int: ...

Default Value

0

Remarks

This property reflects the process Id (PID).

This property reflects the Id of the running process (i.e., the PID).

The running_process_index parameter specifies the index of the item in the array. The size of the array is controlled by the running_process_count property.

This property is read-only.

running_process_process_name Property

This property reflects the name of the process.

Syntax

def get_running_process_process_name(running_process_index: int) -> str: ...

Default Value

""

Remarks

This property reflects the name of the process.

This property reflects the name of the running process.

The running_process_index parameter specifies the index of the item in the array. The size of the array is controlled by the running_process_count property.

This property is read-only.

serialize_events Property

Whether events should be fired on a single worker thread, or many.

Syntax

def get_serialize_events() -> int: ...
def set_serialize_events(value: int) -> None: ...

serialize_events = property(get_serialize_events, set_serialize_events)

Default Value

0

Remarks

This property specifies whether the class should fire all events serially on a single worker thread, or concurrently on multiple worker threads. The possible values are:

0 (seOnMultipleThreads) The class fires events in the context of multiple worker threads. The MinWorkerThreadCount and MaxWorkerThreadCount configuration settings control how many worker threads are used for this.
1 (seOnOneWorkerThread) The class fires events in the context of one background worker thread.

Please refer to the Threading and Concurrency topic for more information.

Note: This property cannot be changed when active is True, and it cannot be changed within events.

strict_altitude Property

This property specifies how to behave if the specified altitude is already in use.

Syntax

def get_strict_altitude() -> bool: ...
def set_strict_altitude(value: bool) -> None: ...

strict_altitude = property(get_strict_altitude, set_strict_altitude)

Default Value

FALSE

Remarks

This property specifies how the class's system driver should behave if the specified altitude is already in use when the start_filter method is called.

If this property is enabled, the filter will fail to attach. If this property is disabled (default), the driver will attempt to use an adjacent altitude value to attach the filter.

tag Property

This property stores application-defined data specific to a particular instance of the class.

Syntax

def get_tag() -> int: ...
def set_tag(value: int) -> None: ...

tag = property(get_tag, set_tag)

Default Value

0

Remarks

This property can be used to store data specific to a particular instance of the class.

track_command_line Property

This property specifies whether the driver should store information about processes' command-line arguments.

Syntax

def get_track_command_line() -> bool: ...
def set_track_command_line(value: bool) -> None: ...

track_command_line = property(get_track_command_line, set_track_command_line)

Default Value

FALSE

Remarks

This property specifies whether the class should store command-line parameters for all processes that are running. Set this property to True if you want to receive command lines for each process during enumeration that is created with create_running_processes_snapshot.

Note: This property cannot be changed when active is True, and it cannot be changed within events.

add_filtered_process_by_id Method

This method adds a process, by process ID (PID), to the list of filtered processes.

Syntax

def add_filtered_process_by_id(process_id: int, include_children: bool) -> None: ...

Remarks

This method adds the process with the specified ProcessId (PID) to the list of processes whose requests should be filtered (i.e., that the class should fire events for).

The ProcessId parameter specifies the PID of the process whose requests should be filtered. The value passed for this parameter must be either the PID of an existing process or -1, which means "all processes".

The IncludeChildren parameter specifies whether requests made by the specified process's children should also be filtered.

Note: This method can be called only when active is True.

add_filtered_process_by_name Method

This method adds a process, by name, to the list of filtered processes.

Syntax

def add_filtered_process_by_name(process_name: str, include_children: bool) -> None: ...

Remarks

This method adds the process with the specified ProcessName to the list of processes whose requests should be filtered (i.e., that the class should fire events for).

The ProcessName parameter must be a valid process executable name. It may optionally begin with a path, and both the name and the path (if present) may include wildcards (* and ?). A process with a matching executable name does not actually need to exist when this method is called.

The IncludeChildren parameter specifies whether requests made by the specified process's children should also be filtered.

Note: This method can be called only when active is True.

add_ignored_process_by_id Method

This method adds a process, by process ID (PID), to the list of ignored processes.

Syntax

def add_ignored_process_by_id(process_id: int, include_children: bool) -> None: ...

Remarks

This method adds the process with the specified ProcessId (PID) to the list of processes whose requests should be ignored (i.e., that the class should not fire events for).

The ProcessId parameter specifies the PID of the process whose requests should be ignored. The value passed for this parameter must be the PID of an existing process.

The IncludeChildren parameter specifies whether requests made by the specified process's children should also be ignored.

Note: The class's system driver ignores all processes' requests by default. Applications should use this method only to explicitly exclude a process that otherwise would be filtered because of a process filtering rule added with add_filtered_process_by_id or add_filtered_process_by_name.

Note: This method can be called only when active is True.

add_ignored_process_by_name Method

This method adds a process, by name, to the list of ignored processes.

Syntax

def add_ignored_process_by_name(process_name: str, include_children: bool) -> None: ...

Remarks

This method adds the process with the specified ProcessName to the list of processes whose requests should be ignored (i.e., that the class should not fire events for).

The ProcessName parameter must be a valid process executable name. It may optionally begin with a path, and both the name and the path (if present) may include wildcards (* and ?). A process with a matching executable name does not actually need to exist when this method is called.

The IncludeChildren parameter specifies whether requests made by the specified process's children should also be ignored.

Note: The class's system driver ignores all processes' requests by default. Applications should use this method only to explicitly exclude a process that otherwise would be filtered because of a process filtering rule added with add_filtered_process_by_id or add_filtered_process_by_name.

Note: This method can be called only when active is True.

close_running_processes_snapshot Method

This method closes the previously created snapshot of running processes.

Syntax

def close_running_processes_snapshot() -> None: ...

Remarks

This method closes the snapshot previously created by create_running_processes_snapshot, releasing the memory associated with it. Please refer to that method's documentation for more information.

Note: This method cannot be called within events.

config Method

Sets or retrieves a configuration setting.

Syntax

def config(configuration_string: str) -> str: ...

Remarks

config is a generic method available in every class. It is used to set and retrieve configuration settings for the class.

These settings are similar in functionality to properties, but they are rarely used. In order to avoid "polluting" the property namespace of the class, access to these internal properties is provided through the config method.

To set a configuration setting named PROPERTY, you must call Config("PROPERTY=VALUE"), where VALUE is the value of the setting expressed as a string. For boolean values, use the strings "True", "False", "0", "1", "Yes", or "No" (case does not matter).

To read (query) the value of a configuration setting, you must call Config("PROPERTY"). The value will be returned as a string.

create_running_processes_snapshot Method

This method creates a snapshot of running processes.

Syntax

def create_running_processes_snapshot() -> None: ...

Remarks

This method creates a snapshot of information about processes that are running in the system. This information is then used to populate the RunningProcesses* properties.

When the application is finished working with the default rules snapshot, it must close it by calling the close_running_processes_snapshot method to release the associated memory. If this method is called again before an existing snapshot is closed, the class will attempt to close it before creating a new one.

Note: This method cannot be called within events.

get_driver_status Method

This method retrieves the status of the class's system driver.

Syntax

def get_driver_status(product_guid: str) -> int: ...

Remarks

This method retrieves the status of the class's system driver. This status can then be used to verify whether it has been properly installed and is ready for use.

The value returned by the method corresponds to the dwCurrentState field of the SERVICE_STATUS structure from the Windows API. It will be one of the following:

MODULE_STATUS_NOT_PRESENT0x00000000The specified module is not present on the system.

MODULE_STATUS_STOPPED0x00000001The specified module is in the Stopped state.

MODULE_STATUS_RUNNING0x00000004The specified module is loaded and running.

ProductGUID is used to distinguish among driver installations performed by different applications. Such information is necessary to guard against unexpected situations, such as the driver being uninstalled by one application despite other applications still needing it.

Therefore, to ensure proper operation, it is critical that each individual application have its own unique ProductGUID value, and that applications (and their installation scripts) use that value when calling any of the following methods:

This method is available in both the class API and the Installer DLL included with the product; please refer to the Driver Installation topic for more information about the latter.

Note: This method cannot be called within events.

get_driver_version Method

This method retrieves the version of the class's system driver.

Syntax

def get_driver_version(product_guid: str) -> int: ...

Remarks

This method retrieves the version of the class's system driver. The value is returned as a 64-bit integer composed of four 16-bit words that each correspond to a piece of the overall module version. For example, a version of 2.32.6.28 would cause the value 0x000200200006001C to be returned.

If the class's system driver is not installed, this method returns 0.

ProductGUID is used to distinguish among driver installations performed by different applications. Such information is necessary to guard against unexpected situations, such as the driver being uninstalled by one application despite other applications still needing it.

Therefore, to ensure proper operation, it is critical that each individual application have its own unique ProductGUID value, and that applications (and their installation scripts) use that value when calling any of the following methods:

This method is available in both the class API and the Installer DLL included with the product; please refer to the Driver Installation topic for more information about the latter.

Note: This method cannot be called within events.

get_originator_token Method

This method retrieves the security token associated with the process that initiated the operation.

Syntax

def get_originator_token() -> int: ...

Remarks

This method can be called within events fired for process and thread operations to retrieve the security token associated with the process that initiated the operation. If the query fails, this method returns INVALID_HANDLE_VALUE.

The security token returned by this method can be passed to the Windows API's GetTokenInformation function to obtain more information about the process.

Note: When applications are finished using the returned security token, they must close it using the Windows API's CloseHandle function.

Note: This method can be called only within events.

get_process_name Method

This method retrieves the name of the process associated with the specified process ID (PID).

Syntax

def get_process_name(process_id: int) -> str: ...

Remarks

This method retrieves the name of the process with the specified ProcessId (PID). If such a process currently exists, this method returns the fully qualified name of its executable; otherwise, it returns an empty string.

Note: The System process does not technically have a name; passing its PID to this method will cause empty string to be returned.

initialize Method

This method initializes the class.

Syntax

def initialize(product_guid: str) -> None: ...

Remarks

This method initializes the class and must be called each time the application starts before attempting to call any of the class's other methods with the exception of installation-related methods.

ProductGUID is used to distinguish among driver installations performed by different applications. Such information is necessary to guard against unexpected situations, such as the driver being uninstalled by one application despite other applications still needing it.

Therefore, to ensure proper operation, it is critical that each individual application have its own unique ProductGUID value, and that applications (and their installation scripts) use that value when calling any of the following methods:

If the required driver was not installed using the install method with the same value of ProductGUID, initialize will return a ERROR_FILE_NOT_FOUND error (Win32 error code 2).

If the loaded kernel-mode driver is older than the user-mode API, initialize will return a ERROR_INVALID_KERNEL_INFO_VERSION error (Win32 error code 340). In this situation, an update of the driver using the install method is required before the class can be used.

install Method

This method installs (or upgrades) the class's system driver.

Syntax

def install(cab_file_name: str, product_guid: str, path_to_install: str, flags: int) -> bool: ...

Remarks

This method is used to install or upgrade the class's system driver. If the system must be rebooted to complete the installation process, this method returns True; otherwise, it returns False.

Important: To upgrade the class's driver, use only the install method. Previously installed versions of the driver should not be uninstalled first. Calling the install method will upgrade the previously installed version.

Please refer to the Driver Installation topic for more information.

CabFileName must be the path of the .cab file containing the class's system driver.

Note: This .cab file must remain on the target system (or be available in some other way) after installation, because it is required to uninstall the driver from the system.

ProductGUID is used to distinguish among driver installations performed by different applications. Such information is necessary to guard against unexpected situations, such as the driver being uninstalled by one application despite other applications still needing it.

Therefore, to ensure proper operation, it is critical that each individual application have its own unique ProductGUID value, and that applications (and their installation scripts) use that value when calling any of the following methods:

PathToInstall controls where the driver is installed. Pass empty string (highly recommended) to automatically install the driver to the appropriate Windows system directory.

Flags specifies various installation options and should contain zero or more of the following flags, ORed together:

INSTALL_REMOVE_OLD_VERSIONS0x00000001Uninstall drivers from previous class versions (e.g., 2017).

INSTALL_KEEP_START_TYPE0x00000002Keep the driver's current start type setting in the registry.

If this flag is not set (default), the installation logic will reset the driver's start type setting in the Windows registry to the default value. Setting this flag causes the installation logic to preserve the current value, which may be necessary if the user (or the application) set it previously.

INSTALL_REQUESTS_VIA_DRIVER_STACK0x00000004Whether internal requests to the filesystem are sent directly to the filesystem driver or through the stack of filesystem filter drivers.

This flag is applicable only for CBFilter and CBMonitor.

After installation, the effects of this flag can be changed using the SendRequestsViaDriverStack configuration setting.

INSTALL_ALWAYS_PREPARE_FILES0x00010000Whether the driver should keep track of information for files that are already open when (i.e., were opened before) the class is initialized.

This flag is applicable only for CBFilter and CBMonitor.

If this flag is set, the driver will prepare information about each file as it is opened, regardless of whether a CBFilter/CBMonitor-based application is actually running at the time. This information then allows applications to receive events for any files that are already open when the CBFilter/CBMonitor class is initialized.

Note: These preparations will slow down all file open operations; do not enable this feature unless it is actually necessary.

After installation, the effects of this flag can be changed using the AlwaysPrepareFiles configuration setting.

INSTALL_FORCE_APP_PERMISSION_CHECK0x00020000Whether the driver should require the controller process to have elevated or system privileges.

This flag is not applicable for CBProcess.

If this flag is set, the driver will verify that the controller process is a system service (or is executing with elevated privileges) anytime a file is opened. If the controller process does not meet these requirements, the file will be skipped (i.e., not filtered in any way).

Note: This additional verification will slow down all file open operations.

After installation, the effects of this flag can be changed using the ForceAppPermissionCheck configuration setting.

INSTALL_FORCE_SECURITY_CHECKS0x00040000Whether the driver should prevent the controller process from filtering files that it would not normally have access to.

This flag is not applicable for CBProcess.

If this flag is set, the driver will check the security permissions of the controller process anytime a file is opened to verify that the process has access to the file. If the controller process does not have access to the file, the file will be skipped (i.e., not filtered in any way). For example, if this flag is set and the controller process is running with limited privileges, then the driver will not allow it to filter files that require greater privileges to access.

Note: This additional verification will slow down all file open operations.

After installation, the effects of this flag can be changed using the ForceSecurityChecks configuration setting.

This method is available in both the class API and the Installer DLL included with the product; please refer to the Driver Installation topic for more information about the latter.

This method requires administrative rights to execute successfully. If the user account of the process that calls this method doesn't have such rights, the call will fail with an ERROR_PRIVILEGE_NOT_HELD (0x0522) error.

Note: This method cannot be called within events.

remove_filtered_process_by_id Method

This method removes a process, by process ID (PID), from the list of filtered processes.

Syntax

def remove_filtered_process_by_id(process_id: int) -> None: ...

Remarks

This method removes the process with the specified ProcessId (PID) from the list of processes whose requests should be filtered.

The value passed for ProcessId must be one that was previously used to call add_filtered_process_by_id; please refer to its documentation for more information.

Note: This method can be called only when active is True.

remove_filtered_process_by_name Method

This method removes a process, by name, from the list of filtered processes.

Syntax

def remove_filtered_process_by_name(process_name: str) -> None: ...

Remarks

This method removes the process with the specified ProcessName from the list of processes whose requests should be filtered.

The value passed for ProcessName must be one that was previously used to call add_filtered_process_by_name; please refer to its documentation for more information.

Note: This method can be called only when active is True.

remove_ignored_process_by_id Method

This method removes a process, by process ID (PID), from the list of ignored processes.

Syntax

def remove_ignored_process_by_id(process_id: int) -> None: ...

Remarks

This method removes the process with the specified ProcessId (PID) from the list of processes whose requests should be ignored.

The value passed for ProcessId must be one that was previously used to call add_ignored_process_by_id; please refer to its documentation for more information.

Note: This method can be called only when active is True.

remove_ignored_process_by_name Method

This method removes a process, by name, from the list of ignored processes.

Syntax

def remove_ignored_process_by_name(process_name: str) -> None: ...

Remarks

This method removes the process with the specified ProcessName from the list of processes whose requests should be ignored.

The value passed for ProcessName must be one that was previously used to call add_ignored_process_by_name; please refer to its documentation for more information.

Note: This method can be called only when active is True.

reset_timeout Method

This method resets the timeout duration for the current event handler.

Syntax

def reset_timeout(timeout: int) -> bool: ...

Remarks

When event timeouts are being enforced, this method can be called within an event handler to inform the class that request processing is taking longer than expected.

If called successfully, this method returns True, and the current event handler's timeout timer is immediately reset to 0; when it reaches the number of milliseconds specified by Timeout, the driver will either "release" the underlying request and pass it onwards, or cancel it by reporting an error; whichever is most appropriate for the event in question. Please refer to the Timeouts topic for more information.

Passing 0 for Timeout disables the timeout timer for the current event handler, allowing it to take as long as it needs to complete.

Note: This method can be called only within events.

shutdown_system Method

Shuts down or reboots the operating system.

Syntax

def shutdown_system(shutdown_prompt: str, timeout: int, force_close_apps: bool, reboot: bool) -> bool: ...

Remarks

This method shuts down or (if Reboot is True) reboots the operating system. If the appropriate privileges cannot be obtained, or if the InitiateSystemShutdown system call returns False, then this method will return False; otherwise, it returns True. This method can be used if the installation or uninstallation function requires the system to be rebooted in order to complete.

ShutdownPrompt, if non-empty, specifies a message that the OS should display to the user for Timeout seconds. If empty string is passed for ShutdownPrompt, no message is displayed and the Timeout parameter's value is ignored.

ForceCloseApps specifies whether the OS should forcefully close all applications. Please keep in mind that forceful closing of applications with unsaved data can lead to data loss.

Reboot specifies whether the OS should reboot (True) or just shut down (False).

This method is available in both the class API and the Installer DLL included with the product; please refer to the Driver Installation topic for more information about the latter.

Note: This method cannot be called within events.

start_filter Method

This method starts the filtering process and thread operations.

Syntax

def start_filter(timeout: int) -> None: ...

Remarks

This method attaches the filter, causing the class's system driver to start the filtering process and thread operations according to the filter rules currently present. Rules can be added and removed both before and after this method is called, so long as the initialize method is called before doing anything else.

The Timeout parameter specifies how many milliseconds the driver should wait for events to execute before releasing or cancelling the underlying OS requests; please refer to the Timeouts topic for more information. Valid values are 0, which disables event timeouts, and values greater than or equal to 3000. When event timeouts are in effect, event handlers can call reset_timeout to reset the timer if they require additional time to complete.

This method can fail for a number of reasons, including (but not limited to) the following:

  • If the class's system driver has not been properly installed, or is awaiting a system reboot (as indicated by the return value of install), this method fails with an ERROR_FILE_NOT_FOUND (2) error code.
  • If the initialize method has not been called yet, this method fails with an ERROR_NOT_READY (21) error code.
  • If the filter is already active, this method fails with an ERROR_CONNECTION_ACTIVE (1230) error code.
  • If an invalid value is passed for Timeout, this method fails with an ERROR_IMPLEMENTATION_LIMIT (1292) error code.

stop_filter Method

This method stops the filtering process and thread operations.

Syntax

def stop_filter() -> None: ...

Remarks

This method detaches the filter, causing the class's system driver to stop the filtering process and thread operations. This method will block until all pending requests have been completed and the filter has been detached.

uninstall Method

This method uninstalls the class's system driver.

Syntax

def uninstall(cab_file_name: str, product_guid: str, installed_path: str, flags: int) -> bool: ...

Remarks

This method is used to uninstall the class's system driver. If the system must be rebooted to complete the uninstallation process, this method returns True; otherwise, it returns False.

Important: To upgrade the class's driver, use only the install method. Previously installed versions of the driver should not be uninstalled first. Calling the install method will upgrade the previously installed version.

Please refer to the Driver Installation topic for more information.

The same values must be passed for the CabFileName, ProductGUID, and InstalledPath parameters as were passed when install was called; please refer to its documentation for more information.

Flags specifies which versions of the class's system driver should be uninstalled and which should be set by ORing together one or more of the following values:

UNINSTALL_VERSION_PREVIOUS0x00000001Uninstall modules from previous product versions.

UNINSTALL_VERSION_CURRENT0x00000002Uninstall modules from the current product version.

UNINSTALL_VERSION_ALL0x00000003Uninstall modules from all product versions.

This method is available in both the class API and the Installer DLL included with the product; please refer to the Driver Installation topic for more information about the latter.

This method requires administrative rights to execute successfully. If the user account of the process that calls this method doesn't have such rights, the call will fail with an ERROR_PRIVILEGE_NOT_HELD (0x0522) error.

Note: This method cannot be called within events.

on_error Event

This event fires if an unhandled error occurs during an event.

Syntax

class CBProcessErrorEventParams(object):
  @property
  def error_code() -> int: ...

  @property
  def description() -> str: ...

# In class CBProcess:
@property
def on_error() -> Callable[[CBProcessErrorEventParams], None]: ...
@on_error.setter
def on_error(event_hook: Callable[[CBProcessErrorEventParams], None]) -> None: ...

Remarks

This event fires if an unhandled error occurs during another event. Developers can use this information to track down unhandled errors in an application's event handlers.

Note: Not everything is possible or allowed in the event handlers. For details, see the Recursive Calls topic.

on_process_creation Event

This event fires when a process is being created.

Syntax

class CBProcessProcessCreationEventParams(object):
  @property
  def process_id() -> int: ...

  @property
  def parent_process_id() -> int: ...

  @property
  def creating_process_id() -> int: ...

  @property
  def creating_thread_id() -> int: ...

  @property
  def process_name() -> str: ...

  @property
  def image_file_name() -> str: ...

  @property
  def file_open_name_available() -> bool: ...

  @property
  def command_line() -> str: ...

  @property
  def result_code() -> int: ...
  @result_code.setter
  def result_code(value) -> None: ...

# In class CBProcess:
@property
def on_process_creation() -> Callable[[CBProcessProcessCreationEventParams], None]: ...
@on_process_creation.setter
def on_process_creation(event_hook: Callable[[CBProcessProcessCreationEventParams], None]) -> None: ...

Remarks

This event fires when a process is being created, after its first thread is created but before it begins running.

Applications may use this event to cancel the process creation by returning an appropriate error code (e.g., ACCESS_DENIED) via ResultCode.

The ProcessId parameter reflects the Id of the process being created.

The ParentProcessId parameter reflects the Id of the new process's parent process, from which it may inherit certain resources (e.g., handles, shared memory).

The CreatingProcessId parameter reflects the Id of the process that created the new process (which is not always the same as its parent process).

The CreatingThreadId parameter reflects the Id of the thread that created the new process.

The ProcessName parameter reflects the name of the new process. This parameter's value is the same one that the get_process_name method would return for ProcessId.

The ImageFileName parameter reflects the name of the new process's executable file, as either a partial or a fully qualified file path.

The FileOpenNameAvailable parameter indicates whether the ImageFileName parameter's contains a fully qualified file path (True) or a partial one (False).

The CommandLine parameter reflects the command line used to start the new process.

Note: To use the event, enable it via the rcfgEventsToFire; configuration setting. For this event to fire, the creating process must match the rules that were added using add_filtered_process_by_id or add_filtered_process_by_name. Additionally, if the creating process is the same process that controls the instance of the class, the FilterOwnRequests configuration setting must be set to True.

The ResultCode parameter will always be 0 when the event is fired. If the event cannot be handled in a "successful" manner for some reason (e.g., a resource is not available or security checks failed), set it to a nonzero value to report an appropriate error. Please see the Error Reporting and Handling topic for more information.

This event is fired synchronously; please refer to the Event Types topic for more information.

on_process_handle_operation Event

This event fires when a process handle is being created or duplicated.

Syntax

class CBProcessProcessHandleOperationEventParams(object):
  @property
  def duplication() -> bool: ...

  @property
  def process_id() -> int: ...

  @property
  def originator_process_id() -> int: ...

  @property
  def originator_thread_id() -> int: ...

  @property
  def source_process_id() -> int: ...

  @property
  def target_process_id() -> int: ...

  @property
  def original_desired_access() -> int: ...

  @property
  def desired_access() -> int: ...
  @desired_access.setter
  def desired_access(value) -> None: ...

  @property
  def result_code() -> int: ...
  @result_code.setter
  def result_code(value) -> None: ...

# In class CBProcess:
@property
def on_process_handle_operation() -> Callable[[CBProcessProcessHandleOperationEventParams], None]: ...
@on_process_handle_operation.setter
def on_process_handle_operation(event_hook: Callable[[CBProcessProcessHandleOperationEventParams], None]) -> None: ...

Remarks

This event fires when a process handle is being created or duplicated. The new handle allows operations to be performed on the associated process.

Applications may use this event to restrict the access rights that will be granted to the new process handle. For example, to prevent process termination, the application could remove the PROCESS_TERMINATE flag.

The Duplication parameter indicates whether a new process handle is being create (False) or an existing one is being duplicated (True).

The ProcessId parameter reflects the Id of the process whose handle is being created or duplicated.

The OriginatorProcessId parameter reflects the Id of the process that requested a handle be created or duplicated.

The OriginatorThreadId parameter reflects the Id of the thread that requested a handle be created or duplicated.

The SourceProcessId and TargetProcessId parameters reflect the Id of the process that is the source of the handle, and the Id of the process that receives the duplicated handle, respectively. (These parameters' values are valid only if Duplication is True.)

The OriginalDesiredAccess parameter reflects the access rights originally requested for the new handle.

The DesiredAccess parameter specifies the access rights that should be granted to the new handle; it will match OriginalDesiredAccess initially. Applications can remove access flags from this value, but they cannot add additional flags.

Please refer to Microsoft's OB_PRE_CREATE_HANDLE_INFORMATION structure documentation for more information about possible access flags.

The ResultCode parameter will always be 0 when the event is fired. If the event cannot be handled in a "successful" manner for some reason (e.g., a resource is not available or security checks failed), set it to a nonzero value to report an appropriate error. Please see the Error Reporting and Handling topic for more information.

Note: To use the event, enable it via the rcfgEventsToFire; configuration setting.

Note: The system APIs offer no way to report errors that occur during the processing of this request. Therefore, exceptional ResultCode values are largely ignored.

This event is fired synchronously; please refer to the Event Types topic for more information.

on_process_termination Event

This event fires when a process is being terminated.

Syntax

class CBProcessProcessTerminationEventParams(object):
  @property
  def process_id() -> int: ...

  @property
  def process_name() -> str: ...

  @property
  def result_code() -> int: ...
  @result_code.setter
  def result_code(value) -> None: ...

# In class CBProcess:
@property
def on_process_termination() -> Callable[[CBProcessProcessTerminationEventParams], None]: ...
@on_process_termination.setter
def on_process_termination(event_hook: Callable[[CBProcessProcessTerminationEventParams], None]) -> None: ...

Remarks

This event fires when a process is being terminated, just before its last thread is destroyed.

Applications cannot prevent a process from being terminated using this event; use the on_process_handle_operation event instead.

The ProcessId parameter reflects the Id of the terminating process.

The ProcessName parameter reflects the name of the terminating process. This parameter's value is the same one that the get_process_name method would return for ProcessId.

Note: To use the event, enable it via the rcfgEventsToFire; configuration setting.

The ResultCode parameter will always be 0 when the event is fired. If the event cannot be handled in a "successful" manner for some reason (e.g., a resource is not available or security checks failed), set it to a nonzero value to report an appropriate error. Please see the Error Reporting and Handling topic for more information.

Note: The system APIs offer no way to report errors that occur during the processing of this request. Therefore, exceptional ResultCode values are largely ignored.

This event is fired synchronously; please refer to the Event Types topic for more information.

on_thread_creation Event

This event fires when a thread is being created.

Syntax

class CBProcessThreadCreationEventParams(object):
  @property
  def process_id() -> int: ...

  @property
  def thread_id() -> int: ...

  @property
  def creating_process_id() -> int: ...

  @property
  def creating_thread_id() -> int: ...

  @property
  def result_code() -> int: ...
  @result_code.setter
  def result_code(value) -> None: ...

# In class CBProcess:
@property
def on_thread_creation() -> Callable[[CBProcessThreadCreationEventParams], None]: ...
@on_thread_creation.setter
def on_thread_creation(event_hook: Callable[[CBProcessThreadCreationEventParams], None]) -> None: ...

Remarks

This event fires when a thread is being created, before it is started.

Applications cannot cancel thread creation; any errors returned during this event are ignored.

The ProcessId parameter reflects the Id of the process to which the new thread belongs.

The ThreadId parameter reflects the Id of the new thread.

The CreatingProcessId parameter reflects the Id of the process that created the new thread.

The CreatingThreadId parameter reflects the Id of the thread that created the new thread.

Note: To use the event, enable it via the rcfgEventsToFire; configuration setting.

The ResultCode parameter will always be 0 when the event is fired. If the event cannot be handled in a "successful" manner for some reason (e.g., a resource is not available or security checks failed), set it to a nonzero value to report an appropriate error. Please see the Error Reporting and Handling topic for more information.

Note: The system APIs offer no way to report errors that occur during the processing of this request. Therefore, exceptional ResultCode values are largely ignored.

This event is fired synchronously; please refer to the Event Types topic for more information.

on_thread_handle_operation Event

This event fires when a thread handle is being created or duplicated.

Syntax

class CBProcessThreadHandleOperationEventParams(object):
  @property
  def duplication() -> bool: ...

  @property
  def process_id() -> int: ...

  @property
  def thread_id() -> int: ...

  @property
  def originator_process_id() -> int: ...

  @property
  def originator_thread_id() -> int: ...

  @property
  def source_process_id() -> int: ...

  @property
  def target_process_id() -> int: ...

  @property
  def original_desired_access() -> int: ...

  @property
  def desired_access() -> int: ...
  @desired_access.setter
  def desired_access(value) -> None: ...

  @property
  def result_code() -> int: ...
  @result_code.setter
  def result_code(value) -> None: ...

# In class CBProcess:
@property
def on_thread_handle_operation() -> Callable[[CBProcessThreadHandleOperationEventParams], None]: ...
@on_thread_handle_operation.setter
def on_thread_handle_operation(event_hook: Callable[[CBProcessThreadHandleOperationEventParams], None]) -> None: ...

Remarks

This event fires when a thread handle is being created or duplicated. The new handle allows operations to be performed on the associated thread.

Applications may use this event to restrict the access rights that will be granted to the new thread handle. For example, to prevent thread termination, the application could remove the THREAD_TERMINATE flag.

The Duplication parameter indicates whether a new thread handle is being created (False), or an existing one is being duplicated (True).

The ProcessId parameter reflects the Id of the process whose thread's handle is being created or duplicated.

The ThreadId parameter reflects the Id of the thread whose handle is being created or duplicated.

Note: To use the event, enable it via the rcfgEventsToFire; configuration setting.

The OriginatorProcessId parameter reflects the Id of the process that requested a handle be created or duplicated.

The OriginatorThreadId parameter reflects the Id of the thread that requested a handle be created or duplicated.

The SourceProcessId and TargetProcessId parameters reflect the Id of the process that is the source of the handle, and the Id of the process that receives the duplicated handle, respectively. (These parameters' values are valid only if Duplication is True.)

The OriginalDesiredAccess parameter reflects the access rights originally requested for the new handle.

The DesiredAccess parameter specifies the access rights that should be granted to the new handle; it will match OriginalDesiredAccess initially. Applications can remove access flags from this value, but they cannot add additional flags.

Please refer to Microsoft's OB_PRE_CREATE_HANDLE_INFORMATION structure documentation for more information about possible access flags.

The ResultCode parameter will always be 0 when the event is fired. If the event cannot be handled in a "successful" manner for some reason (e.g., a resource is not available or security checks failed), set it to a nonzero value to report an appropriate error. Please see the Error Reporting and Handling topic for more information.

Note: The system APIs offer no way to report errors that occur during the processing of this request. Therefore, exceptional ResultCode values are largely ignored.

This event is fired synchronously; please refer to the Event Types topic for more information.

on_thread_termination Event

This event fires when a thread is being terminated.

Syntax

class CBProcessThreadTerminationEventParams(object):
  @property
  def process_id() -> int: ...

  @property
  def thread_id() -> int: ...

  @property
  def result_code() -> int: ...
  @result_code.setter
  def result_code(value) -> None: ...

# In class CBProcess:
@property
def on_thread_termination() -> Callable[[CBProcessThreadTerminationEventParams], None]: ...
@on_thread_termination.setter
def on_thread_termination(event_hook: Callable[[CBProcessThreadTerminationEventParams], None]) -> None: ...

Remarks

This event fires when a thread is being terminated.

Applications cannot prevent a thread from being terminated using this event; use the on_thread_handle_operation event instead.

The ProcessId parameter reflects the Id of process whose thread is being terminated.

The ThreadId parameter reflects the Id of the terminating thread.

Note: To use the event, enable it via the rcfgEventsToFire; configuration setting.

The ResultCode parameter will always be 0 when the event is fired. If the event cannot be handled in a "successful" manner for some reason (e.g., a resource is not available or security checks failed), set it to a nonzero value to report an appropriate error. Please see the Error Reporting and Handling topic for more information.

Note: The system APIs offer no way to report errors that occur during the processing of this request. Therefore, exceptional ResultCode values are largely ignored.

This event is fired synchronously; please refer to the Event Types topic for more information.

on_worker_thread_creation Event

Fires just after a new worker thread is created.

Syntax

class CBProcessWorkerThreadCreationEventParams(object):
  @property
  def result_code() -> int: ...
  @result_code.setter
  def result_code(value) -> None: ...

# In class CBProcess:
@property
def on_worker_thread_creation() -> Callable[[CBProcessWorkerThreadCreationEventParams], None]: ...
@on_worker_thread_creation.setter
def on_worker_thread_creation(event_hook: Callable[[CBProcessWorkerThreadCreationEventParams], None]) -> None: ...

Remarks

This event fires just after a worker thread is created, in the context of that worker thread.

This event is optional; it is provided to give applications a chance to perform additional processing when a new worker thread is created, such as allocating per-thread objects.

The class maintains a pool of worker threads and uses them to fire events; please refer to the Threading and Concurrency topic for more information.

The ResultCode parameter will always be 0 when the event is fired. If the event cannot be handled in a "successful" manner for some reason (e.g., a resource is not available or security checks failed), set it to a nonzero value to report an appropriate error. Please see the Error Reporting and Handling topic for more information.

This event is fired synchronously; please refer to the Event Types topic for more information.

on_worker_thread_termination Event

Fires just before a worker thread is terminated.

Syntax

class CBProcessWorkerThreadTerminationEventParams(object):
# In class CBProcess:
@property
def on_worker_thread_termination() -> Callable[[CBProcessWorkerThreadTerminationEventParams], None]: ...
@on_worker_thread_termination.setter
def on_worker_thread_termination(event_hook: Callable[[CBProcessWorkerThreadTerminationEventParams], None]) -> None: ...

Remarks

This event fires just before a worker thread is terminated, in the context of that worker thread.

This event is optional; it is provided to give applications a chance to perform additional processing before a worker thread is terminated, such as deallocating per-thread objects.

The class maintains a pool of worker threads and uses them to fire events; please refer to the Threading and Concurrency topic for more information.

Any errors that occur during this event are ignored.

This event is fired synchronously; please refer to the Event Types topic for more information.

CBProcess Config Settings

The class accepts one or more of the following configuration settings. Configuration settings are similar in functionality to properties, but they are rarely used. In order to avoid "polluting" the property namespace of the class, access to these internal properties is provided through the config method.

CBProcess Config Settings

EventsToFire:   The types of events that the instance must fire.

This configuration setting specifies the event types that must be fired by the class. The setting should be set by ORing together zero or more flags. Possible values are as follows:

PROC_EVT_NONE0Don't fire for any process operations.

Events will not fire for any process operations.

PROC_EVT_PROCESS_CREATION1Fire during process creation operations.

The on_process_creation event will fire anytime the OS attempts to create a process.

PROC_EVT_PROCESS_TERMINATION2Fire during process closing/termination.

The on_process_termination event will fire when a process is being terminated.

PROC_EVT_PROCESS_HANDLE_OPERATION4Fire during process handle creation or duplication.

The on_process_handle_operation event will fire when a process handle is being created or duplicated.

PROC_EVT_THREAD_CREATION8Fire during thread creation operations.

The on_thread_creation event will fire when a thread is being created, before it is started.

PROC_EVT_THREAD_TERMINATION0x10Fire during thread termination operations.

The on_thread_termination event will fire when a thread is being terminated.

PROC_EVT_THREAD_HANDLE_OPERATION0x20Fire during thread handle creation or duplication.

The on_thread_handle_operation event will fire when a thread handle is being created or duplicated.

PROC_EVT_ALL-1Fire for all process and thread operations.

Events will fire for all thread operations.

For performance reasons, the default value is 0, which means "fire no events".

When an application needs to use specific events, adjust the value and include the flags for the needed events.

FilterOwnRequests:   Whether the class's system driver should filter requests made by the application itself.

This configuration setting specifies whether requests made by the application should be filtered through the class's system driver (assuming that they match one of the rules present at the time). When this setting is disabled (default), and the application performs some operation that would match an existing rule, the driver will explicitly ignore it.

Normally, this setting should remain disabled (especially in production) to reduce the possibility of system deadlocks occurring. Certain situations, however, do require it to be enabled, such as for testing purposes (so that event handlers can be tested with single-process tests).

LoggingEnabled:   Whether extended logging is enabled.

This setting specifies whether extended logging is enabled for this class; it is disabled by default. Please refer to the Error Reporting and Handling topic for more information.

This setting's value is stored in the registry and is persistent; it requires administrative rights to be changed.

MaxWorkerThreadCount:   The maximum number of worker threads to use to fire events.

This setting specifies the maximum number of worker threads the class may create to fire events on when the serialize_events property is set to seOnMultipleThreads. (If other cases, this setting does not apply.)

By default, this setting is set to 0, and the driver automatically chooses an optimal number of threads using this equation: 4 * number_of_processors.

MinWorkerThreadCount:   The minimum number of worker threads to use to fire events.

This setting specifies the minimum number of worker threads the class should create to fire events on when the serialize_events property is set to seOnMultipleThreads. (In other cases, this setting does not apply.)

By default, this setting is set to 0, and the driver automatically chooses an optimal number of threads using this equation: max(number_of_processors, 4). If this setting's value exceeds the MaxWorkerThreadCount value, the latter is used instead.

WorkerInitialStackSize:   The initial stack size to create worker threads with.

This setting specifies the initial size of the stack each worker thread is created with. The system rounds this value to the nearest page.

By default, this setting is set to 0, and the driver uses a default stack size (currently, 1 MB).

Note: This setting cannot be changed when active is True, and it cannot be changed within events.

Base Config Settings

BuildInfo:   Information about the product's build.

When queried, this setting will return a string containing information about the product's build.

LicenseInfo:   Information about the current license.

When queried, this setting will return a string containing information about the license this instance of a class is using. It will return the following information:

  • Product: The product the license is for.
  • Product Key: The key the license was generated from.
  • License Source: Where the license was found (e.g., RuntimeLicense, License File).
  • License Type: The type of license installed (e.g., Royalty Free, Single Server).

CBProcess Errors

The class uses Windows error codes during operation as necessary. Please refer to the Error Reporting and Handling topic for more information.

Special Use Errors

21   ERROR_NOT_READY: Reported by the methods of the class if initialize has not been called or did not succeed.
575   ERROR_APP_INIT_FAILURE: Reported by the methods of the class if initialize has not been called or did not succeed. Differs from ERROR_NOT_READY (21) in that it indicates a specific situation in the internal code.
588   ERROR_FS_DRIVER_REQUIRED: Reported if the required system module was not correctly installed for the given ProductGUID.
614   ERROR_NO_CALLBACK_ACTIVE: Reported by any method that can only be called within event handlers if it is called outside an event handler.
1292   ERROR_IMPLEMENTATION_LIMIT: Reported when the timeout value provided is less than 3 seconds.
1314   ERROR_PRIVILEGE_NOT_HELD: Reported by any method that requires elevated permissions if it is called without such permissions.