NtQueryInformationToken function (ntifs.h)
The NtQueryInformationToken routine retrieves a specified type of information about an access token. The calling process must have appropriate access rights to obtain the information.
Syntax
__kernel_entry NTSYSCALLAPI NTSTATUS NtQueryInformationToken(
[in] HANDLE TokenHandle,
[in] TOKEN_INFORMATION_CLASS TokenInformationClass,
[out] PVOID TokenInformation,
[in] ULONG TokenInformationLength,
[out] PULONG ReturnLength
);
Parameters
[in] TokenHandle
Handle for an access token from which information is to be retrieved. If TokenInformationClass is set to TokenSource, the handle must have TOKEN_QUERY_SOURCE access. For all other TokenInformationClass values, the handle must have TOKEN_QUERY access. For more information about access rights for access-token objects, see the Security section of the Windows SDK documentation.
[in] TokenInformationClass
A value from the TOKEN_INFORMATION_CLASS enumerated type identifying the type of information to be retrieved. The possible values for this parameter are listed in the TokenInformationClass Value column of the table shown in the description of the TokenInformation parameter.
[out] TokenInformation
Pointer to a caller-allocated buffer that receives the requested information about the token. The structure put into this buffer depends upon the value of TokenInformationClass, as shown in the following table. All structures must be aligned on a 32-bit boundary.
| TokenInformationClass value | Effect on TokenInformation buffer |
|---|---|
| TokenDefaultDacl | The buffer receives a TOKEN_DEFAULT_DACL structure containing the default DACL for newly created objects. |
| TokenGroups | The buffer receives a TOKEN_GROUPS structure containing the group accounts associated with the token. |
| TokenImpersonationLevel | The buffer receives a SECURITY_IMPERSONATION_LEVEL value indicating the impersonation level of the token. If the access token is not an impersonation token, the call to NtQueryInformationToken fails. |
| TokenOwner | The buffer receives a TOKEN_OWNER structure containing the default owner SID for newly created objects. |
| TokenPrimaryGroup | The buffer receives a TOKEN_PRIMARY_GROUP structure containing the default primary group SID for newly created objects. |
| TokenPrivileges | The buffer receives a TOKEN_PRIVILEGES structure containing the token's privileges. |
| TokenSessionId | The buffer receives a 32-bit value specifying the Terminal Services session identifier associated with the token. If the token is associated with the Terminal Server console session, the session identifier is zero. A nonzero session identifier indicates a Terminal Services client session. In a non-Terminal Services environment, the session identifier is zero. |
| TokenSource | The buffer receives a TOKEN_SOURCE structure containing the source of the token. TOKEN_QUERY_SOURCE access is needed to retrieve this information. |
| TokenStatistics | The buffer receives a TOKEN_STATISTICS structure containing various token statistics. |
| TokenType | The buffer receives a TOKEN_TYPE value indicating whether the token is a primary or impersonation token. |
| TokenUser | The buffer receives a TOKEN_USER structure containing the token's user account. |
[in] TokenInformationLength
Length, in bytes, of the caller-allocated TokenInformation buffer.
[out] ReturnLength
Pointer to a caller-allocated variable that receives the actual length, in bytes, of the information returned in the TokenInformation buffer. If either of the following conditions is true, no data is returned in the TokenInformation buffer:
The size of the requested token information structure is greater than TokenInformationLength. In this case, ReturnLength receives the actual number of bytes needed to store the requested information.
The value of TokenInformationClass is TokenDefaultDacl, and there is no default DACL established for the token. In this case, ReturnLength receives zero.
ReturnLength cannot be NULL. See Remarks for further information.
Return value
NtQueryInformationToken returns STATUS_SUCCESS or an appropriate error status. Possible error status codes include the following:
| Return code | Description |
|---|---|
| STATUS_ACCESS_DENIED | TokenHandle did not have the required access. |
| STATUS_BUFFER_TOO_SMALL | The size of the requested token information structure is greater than TokenInformationLength. The number of bytes required is returned in ReturnLength. |
| STATUS_ACCESS_VIOLATION | ReturnLength was NULL or was not writable in order to receive the actual length of the information pointed by TokenInformation. |
| STATUS_INVALID_HANDLE | TokenHandle was not a valid handle. |
| STATUS_INVALID_INFO_CLASS | TokenInformationClass was not a valid token information class. |
| STATUS_OBJECT_TYPE_MISMATCH | TokenHandle was not a token handle. |
Remarks
The NtQueryInformationToken routine can be used by a file system or file system filter driver to determine the SID of the caller that initiated the request during IRP_MJ_CREATE processing. If TokenUser is specified for the TokenInformationClass parameter passed to NtQueryInformationToken, a TOKEN_USER structure is returned in the buffer pointed to by the TokenInformation parameter. This returned buffer contains an SID_AND_ATTRIBUTES structure with the user SID.
Due to the nature of token's properties (such as token user, token primary group, privileges, etc, where their contents can vary on each token), ReturnLength is not optional; that is, it cannot be NULL. This is because SID is a variable-length structure whereas a specific privilege can exist in a token but not in another (the privilege count can be different for each token). It's the caller's responsibility to first query the necessary required length size in order to allocate memory to accommodate the requested token information before doing the actual query. That said, it is also the caller's responsibility to provide a valid ReturnLength variable that is writable and not NULL. On a NULL case scenario, the function raises an access violation exception.
For more information about security and access control, see Windows security model for driver developers and the documentation on these topics in the Windows SDK.
Note
If the call to the NtQueryInformationToken function occurs in user mode, you should use the name "NtQueryInformationToken" instead of "ZwQueryInformationToken".
For calls from kernel-mode drivers, the NtXxx and ZwXxx versions of a Windows Native System Services routine can behave differently in the way that they handle and interpret input parameters. For more information about the relationship between the NtXxx and ZwXxx versions of a routine, see Using Nt and Zw Versions of the Native System Services Routines.
Requirements
| Requirement | Value |
|---|---|
| Minimum supported client | Windows XP |
| Target Platform | Universal |
| Header | ntifs.h (include Ntifs.h) |
| Library | NtosKrnl.lib |
| DLL | NtosKrnl.exe |
| IRQL | PASSIVE_LEVEL |
| DDI compliance rules | HwStorPortProhibitedDDIs, PowerIrpDDis |