From 75ff4ece7de8c10838f9fab48abfd72819ba96fa Mon Sep 17 00:00:00 2001
From: Alan Jowett <alanjo@microsoft.com>
Date: Fri, 10 Jul 2026 15:42:55 -0700
Subject: [PATCH] Add usersim ring mapping helpers

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Copilot-Session: e4f2928d-308e-4fec-8aa3-280de1761d0c
Signed-off-by: Alan Jowett <alanjo@microsoft.com>
---
 inc/usersim/mm.h | 19 +++++++++++++++++++
 inc/usersim/ob.h | 10 ++++++++++
 src/mm.cpp       | 45 +++++++++++++++++++++++++++++++++++++++++++++
 src/ob.cpp       | 23 +++++++++++++++++++++++
 4 files changed, 97 insertions(+)

diff --git a/inc/usersim/mm.h b/inc/usersim/mm.h
index 2e6b2ba..77de71d 100644
--- a/inc/usersim/mm.h
+++ b/inc/usersim/mm.h
@@ -113,6 +113,25 @@ USERSIM_API
 void
 MmUnmapLockedPages(_In_ void* base_address, _In_ MDL* memory_descriptor_list);
 
+USERSIM_API
+void
+MmProbeAndLockPages(
+    _Inout_ MDL* memory_descriptor_list,
+    __drv_strictType(KPROCESSOR_MODE / enum _MODE, __drv_typeConst) KPROCESSOR_MODE access_mode,
+    ULONG operation);
+
+USERSIM_API
+void
+MmUnlockPages(_Inout_ MDL* memory_descriptor_list);
+
+USERSIM_API
+NTSTATUS
+MmMapViewInSystemSpace(_In_ void* section, _Outptr_ void** mapped_base, _Inout_ SIZE_T* view_size);
+
+USERSIM_API
+NTSTATUS
+MmUnmapViewInSystemSpace(_In_ void* mapped_base);
+
 USERSIM_API
 NTSTATUS
 MmProtectMdlSystemAddress(_In_ MDL* memory_descriptor_list, ULONG new_protect);
diff --git a/inc/usersim/ob.h b/inc/usersim/ob.h
index 29df01b..7d4dabd 100644
--- a/inc/usersim/ob.h
+++ b/inc/usersim/ob.h
@@ -28,6 +28,16 @@ _IRQL_requires_max_(PASSIVE_LEVEL) USERSIM_API NTSTATUS ObReferenceObjectByHandl
     _Out_ PVOID* object,
     _Out_opt_ POBJECT_HANDLE_INFORMATION handle_information);
 
+_IRQL_requires_max_(PASSIVE_LEVEL) USERSIM_API NTSTATUS
+ObOpenObjectByPointer(
+    _In_ PVOID object,
+    _In_ ULONG handle_attributes,
+    _In_opt_ void* passed_access_state,
+    _In_ ACCESS_MASK desired_access,
+    _In_opt_ POBJECT_TYPE object_type,
+    _In_ KPROCESSOR_MODE access_mode,
+    _Out_ HANDLE* handle);
+
 USERSIM_API
 NTSTATUS
 ObCloseHandle(_In_ _Post_ptr_invalid_ HANDLE handle, _In_ KPROCESSOR_MODE previous_mode);
diff --git a/src/mm.cpp b/src/mm.cpp
index d84da98..670823c 100644
--- a/src/mm.cpp
+++ b/src/mm.cpp
@@ -8,6 +8,7 @@
 #include "usersim/ex.h"
 #include "usersim/ke.h"
 #include "usersim/mm.h"
+#include "utilities.h"
 
 // Mm* functions.
 
@@ -132,6 +133,50 @@ MmUnmapLockedPages(_In_ void* base_address, _In_ MDL* memory_descriptor_list)
     return MmUnmapLockedPagesCPP(base_address, memory_descriptor_list);
 }
 
+void
+MmProbeAndLockPages(
+    _Inout_ MDL* memory_descriptor_list,
+    __drv_strictType(KPROCESSOR_MODE / enum _MODE, __drv_typeConst) KPROCESSOR_MODE access_mode,
+    ULONG operation)
+{
+    UNREFERENCED_PARAMETER(memory_descriptor_list);
+    UNREFERENCED_PARAMETER(access_mode);
+    UNREFERENCED_PARAMETER(operation);
+}
+
+void
+MmUnlockPages(_Inout_ MDL* memory_descriptor_list)
+{
+    UNREFERENCED_PARAMETER(memory_descriptor_list);
+}
+
+NTSTATUS
+MmMapViewInSystemSpace(_In_ void* section, _Outptr_ void** mapped_base, _Inout_ SIZE_T* view_size)
+{
+    HANDLE section_handle = (HANDLE)section;
+    void* view;
+
+    view = MapViewOfFile(section_handle, FILE_MAP_ALL_ACCESS, 0, 0, *view_size);
+    if (view == nullptr) {
+        USERSIM_LOG_WIN32_API_FAILURE(USERSIM_TRACELOG_KEYWORD_BASE, MapViewOfFile);
+        return win32_error_to_usersim_error(GetLastError());
+    }
+
+    *mapped_base = view;
+    return STATUS_SUCCESS;
+}
+
+NTSTATUS
+MmUnmapViewInSystemSpace(_In_ void* mapped_base)
+{
+    if (!UnmapViewOfFile(mapped_base)) {
+        USERSIM_LOG_WIN32_API_FAILURE(USERSIM_TRACELOG_KEYWORD_BASE, UnmapViewOfFile);
+        return win32_error_to_usersim_error(GetLastError());
+    }
+
+    return STATUS_SUCCESS;
+}
+
 NTSTATUS
 MmProtectMdlSystemAddress(_In_ MDL* memory_descriptor_list, ULONG new_protect)
 {
diff --git a/src/ob.cpp b/src/ob.cpp
index 0f27781..18e31f3 100644
--- a/src/ob.cpp
+++ b/src/ob.cpp
@@ -4,6 +4,7 @@
 #include "platform.h"
 #include "kernel_um.h"
 #include "usersim/ob.h"
+#include "utilities.h"
 #include <map>
 
 static std::map<PVOID, ULONG> _object_references;
@@ -56,6 +57,28 @@ ObReferenceObjectByHandle(
     return STATUS_SUCCESS;
 }
 
+_IRQL_requires_max_(PASSIVE_LEVEL) USERSIM_API NTSTATUS
+ObOpenObjectByPointer(
+    _In_ PVOID object,
+    _In_ ULONG handle_attributes,
+    _In_opt_ void* passed_access_state,
+    _In_ ACCESS_MASK desired_access,
+    _In_opt_ POBJECT_TYPE object_type,
+    _In_ KPROCESSOR_MODE access_mode,
+    _Out_ HANDLE* handle)
+{
+    UNREFERENCED_PARAMETER(handle_attributes);
+    UNREFERENCED_PARAMETER(passed_access_state);
+    UNREFERENCED_PARAMETER(object_type);
+    UNREFERENCED_PARAMETER(access_mode);
+
+    if (!DuplicateHandle(GetCurrentProcess(), (HANDLE)object, GetCurrentProcess(), handle, desired_access, FALSE, 0)) {
+        return win32_error_to_usersim_error(GetLastError());
+    }
+
+    return STATUS_SUCCESS;
+}
+
 USERSIM_API
 NTSTATUS
 ObCloseHandle(_In_ _Post_ptr_invalid_ HANDLE handle, _In_ KPROCESSOR_MODE previous_mode)