/*++
Copyright (c) 1989 Microsoft Corporation
Module Name:
querysec.c
Abstract:
This module contains the routines which implement the
NtQuerySection service.
Author:
Lou Perazzoli (loup) 22-May-1989
Revision History:
--*/
#include "mi.h"
#ifdef ALLOC_PRAGMA
#pragma alloc_text(PAGE,NtQuerySection)
#endif
NTSTATUS
NtQuerySection(
IN HANDLE SectionHandle,
IN SECTION_INFORMATION_CLASS SectionInformationClass,
OUT PVOID SectionInformation,
IN ULONG SectionInformationLength,
OUT PULONG ReturnLength OPTIONAL
)
/*++
Routine Description:
This function returns information about an opened section object.
This function provides the capability to determine the base address,
size, granted access, and allocation of an opened section object.
Arguments:
SectionHandle - Supplies an open handle to a section object.
SectionInformationClass - The section information class about
which to retrieve information.
SectionInformation - A pointer to a buffer that receives the
specified information. The format and content of the buffer
depend on the specified section class.
SectionInformation Format by Information Class:
SectionBasicInformation - Data type is PSECTION_BASIC_INFORMATION.
SECTION_BASIC_INFORMATION Structure
PVOID BaseAddress - The base virtual address of the
section if the section is based.
LARGE_INTEGER MaximumSize - The maximum size of the section in
bytes.
ULONG AllocationAttributes - The allocation attributes
flags.
AllocationAttributes Flags
SEC_BASED - The section is a based section.
SEC_TILE - The section must be allocated in the first
512mb of the virtual address space.
SEC_FILE - The section is backed by a data file.
SEC_RESERVE - All pages of the section were initially
set to the reserved state.
SEC_COMMIT - All pages of the section were initially
to the committed state.
SEC_IMAGE - The section was mapped as an executable
image file.
SECTION_IMAGE_INFORMATION
SectionInformationLength - Specifies the length in bytes of the
section information buffer.
ReturnLength - An optional pointer which, if specified, receives
the number of bytes placed in the section information buffer.
Return Value:
Returns the status
TBS
--*/
{
PSECTION Section;
KPROCESSOR_MODE PreviousMode;
NTSTATUS Status;
PAGED_CODE();
//
// Get previous processor mode and probe output argument if necessary.
//
PreviousMode = KeGetPreviousMode();
if (PreviousMode != KernelMode) {
//
// Check arguments.
//
try {
ProbeForWrite(SectionInformation,
SectionInformationLength,
sizeof(ULONG));
if (ARGUMENT_PRESENT (ReturnLength)) {
ProbeForWriteUlong(ReturnLength);
}
} except (EXCEPTION_EXECUTE_HANDLER) {
//
// If an exception occurs during the probe or capture
// of the initial values, then handle the exception and
// return the exception code as the status value.
//
return GetExceptionCode();
}
}
//
// Check argument validity.
//
if ((SectionInformationClass != SectionBasicInformation) &&
(SectionInformationClass != SectionImageInformation)) {
return STATUS_INVALID_INFO_CLASS;
}
if (SectionInformationClass == SectionBasicInformation) {
if (SectionInformationLength < (ULONG)sizeof(SECTION_BASIC_INFORMATION)) {
return STATUS_INFO_LENGTH_MISMATCH;
}
} else {
if (SectionInformationLength < (ULONG)sizeof(SECTION_IMAGE_INFORMATION)) {
return STATUS_INFO_LENGTH_MISMATCH;
}
}
//
// Reference section object by handle for READ access, get the information
// from the section object, deference the section
// object, fill in information structure, optionally return the length of
// the information structure, and return service status.
//
Status = ObReferenceObjectByHandle(SectionHandle, SECTION_QUERY,
MmSectionObjectType,
PreviousMode, (PVOID *)&Section, NULL);
if (NT_SUCCESS(Status)) {
try {
if (SectionInformationClass == SectionBasicInformation) {
((PSECTION_BASIC_INFORMATION)SectionInformation)->BaseAddress =
Section->Address.StartingVa;
((PSECTION_BASIC_INFORMATION)SectionInformation)->MaximumSize =
Section->SizeOfSection;
((PSECTION_BASIC_INFORMATION)SectionInformation)->AllocationAttributes =
0;
if (Section->u.Flags.Image) {
((PSECTION_BASIC_INFORMATION)SectionInformation)->AllocationAttributes =
SEC_IMAGE;
}
if (Section->u.Flags.Based) {
((PSECTION_BASIC_INFORMATION)SectionInformation)->AllocationAttributes |=
SEC_BASED;
}
if (Section->u.Flags.File) {
((PSECTION_BASIC_INFORMATION)SectionInformation)->AllocationAttributes |=
SEC_FILE;
}
if (Section->u.Flags.NoCache) {
((PSECTION_BASIC_INFORMATION)SectionInformation)->AllocationAttributes |=
SEC_NOCACHE;
}
if (Section->u.Flags.Reserve) {
((PSECTION_BASIC_INFORMATION)SectionInformation)->AllocationAttributes |=
SEC_RESERVE;
}
if (Section->u.Flags.Commit) {
((PSECTION_BASIC_INFORMATION)SectionInformation)->AllocationAttributes |=
SEC_COMMIT;
}
if (ARGUMENT_PRESENT(ReturnLength)) {
*ReturnLength = sizeof(SECTION_BASIC_INFORMATION);
}
} else {
if (Section->u.Flags.Image == 0) {
return STATUS_SECTION_NOT_IMAGE;
}
*((PSECTION_IMAGE_INFORMATION)SectionInformation) =
Section->Segment->ImageInformation;
if (ARGUMENT_PRESENT(ReturnLength)) {
*ReturnLength = sizeof(SECTION_IMAGE_INFORMATION);
}
}
} except (EXCEPTION_EXECUTE_HANDLER) {
}
ObDereferenceObject ((PVOID)Section);
}
return Status;
}
