[reactos] 01/01: [FREELDR:NTLDR] Stub out x86 PAE support in preparation for PR #4272.

[Vadim Galyant]

https://git.reactos.org/?p=reactos.git;a=commitdiff;h=d4a05ad7aa9372802fb8c…

commit d4a05ad7aa9372802fb8cee4fd8da32a5c707359
Author:     Vadim Galyant <vgal(a)rambler.ru>
AuthorDate: Tue Jan 11 20:37:27 2022 +0400
Commit:     Hermès Bélusca-Maïto <hermes.belusca-maito(a)reactos.org>
CommitDate: Sun Mar 20 04:12:58 2022 +0100

    [FREELDR:NTLDR] Stub out x86 PAE support in preparation for PR #4272.
    
    - Move boot options parsing early on in LoadWindowsCore().
    
    - Add WinLdrIsPaeSupported(), move in it the PAE options parsing.
      The aim is to perform other tests to determine whether or not to
      enable PAE, and select an adequate kernel image.
    
    Co-authored-by: Vadim Galyant <vgal(a)rambler.ru>
    
    - Fix parsing of the NOEXECUTE options, taking their precedence
      into account. Most of these are also x86-specific.
---
 boot/freeldr/freeldr/ntldr/winldr.c | 219 +++++++++++++++++++++++-------------
 boot/freeldr/freeldr/ntldr/winldr.h |   3 +
 2 files changed, 145 insertions(+), 77 deletions(-)

diff --git a/boot/freeldr/freeldr/ntldr/winldr.c b/boot/freeldr/freeldr/ntldr/winldr.c
index 5b06bef6e0f..c923330d6be 100644
--- a/boot/freeldr/freeldr/ntldr/winldr.c
+++ b/boot/freeldr/freeldr/ntldr/winldr.c
@@ -29,12 +29,12 @@ PLOADER_SYSTEM_BLOCK WinLdrSystemBlock;
 
 BOOLEAN VirtualBias = FALSE;
 BOOLEAN SosEnabled = FALSE;
-BOOLEAN PaeEnabled = FALSE;
-BOOLEAN PaeDisabled = FALSE;
 BOOLEAN SafeBoot = FALSE;
 BOOLEAN BootLogo = FALSE;
-BOOLEAN NoexecuteDisabled = FALSE;
-BOOLEAN NoexecuteEnabled = FALSE;
+#ifdef _M_IX86
+BOOLEAN PaeModeOn = FALSE;
+#endif
+BOOLEAN NoExecuteEnabled = FALSE;
 
 // debug stuff
 VOID DumpMemoryAllocMap(VOID);
@@ -534,6 +534,61 @@ LoadModule(
     return BaseAddress;
 }
 
+#ifdef _M_IX86
+static
+BOOLEAN
+WinLdrIsPaeSupported(
+    _In_ USHORT OperatingSystemVersion,
+    _In_ PLOADER_PARAMETER_BLOCK LoaderBlock,
+    _In_ PCSTR BootOptions,
+    _In_ PCSTR HalFileName,
+    _Inout_updates_bytes_(KernelFileNameSize) _Always_(_Post_z_)
+         PSTR KernelFileName,
+    _In_ SIZE_T KernelFileNameSize)
+{
+    BOOLEAN PaeEnabled = FALSE;
+    BOOLEAN PaeDisabled = FALSE;
+    BOOLEAN Result;
+
+    if ((OperatingSystemVersion > _WIN32_WINNT_NT4) &&
+        NtLdrGetOption(BootOptions, "PAE"))
+    {
+        /* We found the PAE option */
+        PaeEnabled = TRUE;
+    }
+
+    Result = PaeEnabled;
+
+    if ((OperatingSystemVersion > _WIN32_WINNT_WIN2K) &&
+        NtLdrGetOption(BootOptions, "NOPAE"))
+    {
+        PaeDisabled = TRUE;
+    }
+
+    if (SafeBoot)
+        PaeDisabled = TRUE;
+
+    TRACE("PaeEnabled %X, PaeDisabled %X\n", PaeEnabled, PaeDisabled);
+
+    if (PaeDisabled)
+        Result = FALSE;
+
+    /* Enable PAE if DEP is enabled */
+    if (NoExecuteEnabled)
+        Result = TRUE;
+
+    // TODO: checks for CPU support, hotplug memory support ... other tests
+    // TODO: select kernel name ("ntkrnlpa.exe" or "ntoskrnl.exe"),
or,
+    // if KernelFileName is a user-specified kernel file, check whether it
+    // has, if PAE needs to be enabled, the IMAGE_FILE_LARGE_ADDRESS_AWARE
+    // Characteristics bit set, and that the HAL image has a similar support.
+
+    if (Result) UNIMPLEMENTED;
+
+    return Result;
+}
+#endif /* _M_IX86 */
+
 static
 BOOLEAN
 LoadWindowsCore(IN USHORT OperatingSystemVersion,
@@ -558,18 +613,87 @@ LoadWindowsCore(IN USHORT OperatingSystemVersion,
     RtlStringCbCopyA(DirPath, sizeof(DirPath), BootPath);
     RtlStringCbCatA(DirPath, sizeof(DirPath), "system32\\");
 
+    /* Parse the boot options */
+    TRACE("LoadWindowsCore: BootOptions '%s'\n", BootOptions);
+
+#ifdef _M_IX86
+    if (NtLdrGetOption(BootOptions, "3GB"))
+    {
+        /* We found the 3GB option. */
+        FIXME("LoadWindowsCore: 3GB - TRUE (not implemented)\n");
+        VirtualBias = TRUE;
+    }
+    // TODO: "USERVA=" for XP/2k3
+#endif
+
+    if ((OperatingSystemVersion > _WIN32_WINNT_NT4) &&
+        (NtLdrGetOption(BootOptions, "SAFEBOOT") ||
+         NtLdrGetOption(BootOptions, "SAFEBOOT:")))
+    {
+        /* We found the SAFEBOOT option. */
+        FIXME("LoadWindowsCore: SAFEBOOT - TRUE (not implemented)\n");
+        SafeBoot = TRUE;
+    }
+
+    if ((OperatingSystemVersion > _WIN32_WINNT_WIN2K) &&
+        NtLdrGetOption(BootOptions, "BOOTLOGO"))
+    {
+        /* We found the BOOTLOGO option. */
+        FIXME("LoadWindowsCore: BOOTLOGO - TRUE (not implemented)\n");
+        BootLogo = TRUE;
+    }
+
+    /* Check the (NO)EXECUTE options */
+    if ((OperatingSystemVersion > _WIN32_WINNT_WIN2K) &&
+        !LoaderBlock->SetupLdrBlock)
+    {
+        /* Disable NX by default on x86, otherwise enable it */
+#ifdef _M_IX86
+        NoExecuteEnabled = FALSE;
+#else
+        NoExecuteEnabled = TRUE;
+#endif
+
+#ifdef _M_IX86
+        /* Check the options in decreasing order of precedence */
+        if (NtLdrGetOption(BootOptions, "NOEXECUTE=OPTIN")  ||
+            NtLdrGetOption(BootOptions, "NOEXECUTE=OPTOUT") ||
+            NtLdrGetOption(BootOptions, "NOEXECUTE=ALWAYSON"))
+        {
+            NoExecuteEnabled = TRUE;
+        }
+        else if (NtLdrGetOption(BootOptions, "NOEXECUTE=ALWAYSOFF"))
+            NoExecuteEnabled = FALSE;
+        else
+#else
+        /* Only the following two options really apply for x64 and other platforms */
+#endif
+        if (NtLdrGetOption(BootOptions, "NOEXECUTE"))
+            NoExecuteEnabled = TRUE;
+        else if (NtLdrGetOption(BootOptions, "EXECUTE"))
+            NoExecuteEnabled = FALSE;
+
+#ifdef _M_IX86
+        /* Disable DEP in SafeBoot mode for x86 only */
+        if (SafeBoot)
+            NoExecuteEnabled = FALSE;
+#endif
+    }
+    TRACE("NoExecuteEnabled %X\n", NoExecuteEnabled);
+
     /*
-     * Default HAL and KERNEL file names.
+     * Select the HAL and KERNEL file names.
+     * Check for any "/HAL=" or "/KERNEL=" override option.
+     *
      * See the following links to know how the file names are actually chosen:
      * https://www.geoffchappell.com/notes/windows/boot/bcd/osloader/detecthal.htm
      * https://www.geoffchappell.com/notes/windows/boot/bcd/osloader/hal.htm
      * https://www.geoffchappell.com/notes/windows/boot/bcd/osloader/kernel.htm
      */
+    /* Default HAL and KERNEL file names */
     RtlStringCbCopyA(HalFileName   , sizeof(HalFileName)   , "hal.dll");
     RtlStringCbCopyA(KernelFileName, sizeof(KernelFileName), "ntoskrnl.exe");
 
-    /* Check for any "/HAL=" or "/KERNEL=" override option */
-
     Option = NtLdrGetOptionEx(BootOptions, "HAL=", &OptionLength);
     if (Option && (OptionLength > 4))
     {
@@ -588,6 +712,17 @@ LoadWindowsCore(IN USHORT OperatingSystemVersion,
         _strlwr(KernelFileName);
     }
 
+#ifdef _M_IX86
+    /* Check for PAE support and select the adequate kernel image */
+    PaeModeOn = WinLdrIsPaeSupported(OperatingSystemVersion,
+                                     LoaderBlock,
+                                     BootOptions,
+                                     HalFileName,
+                                     KernelFileName,
+                                     sizeof(KernelFileName));
+    if (PaeModeOn) FIXME("WinLdrIsPaeSupported: PaeModeOn\n");
+#endif
+
     TRACE("HAL file = '%s' ; Kernel file = '%s'\n",
HalFileName, KernelFileName);
 
     /*
@@ -710,76 +845,6 @@ LoadWindowsCore(IN USHORT OperatingSystemVersion,
         }
     }
 
-    /* Parse the boot options */
-    TRACE("LoadWindowsCore: BootOptions '%s'\n", BootOptions);
-
-    if (NtLdrGetOption(BootOptions, "3GB"))
-    {
-        /* We found the 3GB option. */
-        FIXME("LoadWindowsCore: 3GB - TRUE (not implemented)\n");
-        VirtualBias = TRUE;
-    }
-
-    if (OperatingSystemVersion > _WIN32_WINNT_NT4)
-    {
-        if (NtLdrGetOption(BootOptions, "SAFEBOOT"))
-        {
-            /* We found the SAFEBOOT option. */
-            FIXME("LoadWindowsCore: SAFEBOOT - TRUE (not implemented)\n");
-            SafeBoot = TRUE;
-        }
-        if (NtLdrGetOption(BootOptions, "PAE"))
-        {
-            /* We found the PAE option. */
-            FIXME("LoadWindowsCore: PAE - TRUE (not implemented)\n");
-            PaeEnabled = TRUE;
-        }
-    }
-
-    if (OperatingSystemVersion > _WIN32_WINNT_WIN2K)
-    {
-        if (NtLdrGetOption(BootOptions, "NOPAE"))
-        {
-            /* We found the NOPAE option. */
-            FIXME("LoadWindowsCore: NOPAE - TRUE (not implemented)\n");
-            PaeDisabled = TRUE;
-        }
-        if (NtLdrGetOption(BootOptions, "BOOTLOGO"))
-        {
-            /* We found the BOOTLOGO option. */
-            FIXME("LoadWindowsCore: BOOTLOGO - TRUE (not implemented)\n");
-            BootLogo = TRUE;
-        }
-
-        if (!LoaderBlock->SetupLdrBlock)
-        {
-            if (NtLdrGetOption(BootOptions, "EXECUTE"))
-            {
-                /* We found the EXECUTE option. */
-                FIXME("LoadWindowsCore: EXECUTE - TRUE (not implemented)\n");
-                NoexecuteDisabled = TRUE;
-            }
-            if (NtLdrGetOption(BootOptions, "NOEXECUTE=ALWAYSOFF"))
-            {
-                /* We found the NOEXECUTE=ALWAYSOFF option. */
-                FIXME("LoadWindowsCore: NOEXECUTE=ALWAYSOFF - TRUE (not
implemented)\n");
-                NoexecuteDisabled = TRUE;
-            }
-            if (NtLdrGetOption(BootOptions, "NOEXECUTE"))
-            {
-                /* We found the NOEXECUTE option. */
-                FIXME("LoadWindowsCore: NOEXECUTE - TRUE (not
implemented)\n");
-                NoexecuteEnabled = TRUE;
-            }
-        }
-    }
-
-    if (SafeBoot)
-    {
-        PaeDisabled = TRUE;
-        NoexecuteDisabled = TRUE;
-    }
-
     /* Load all referenced DLLs for Kernel, HAL and Kernel Debugger Transport DLL */
     Success = PeLdrScanImportDescriptorTable(&LoaderBlock->LoadOrderListHead,
DirPath, *KernelDTE);
     if (!Success)
diff --git a/boot/freeldr/freeldr/ntldr/winldr.h b/boot/freeldr/freeldr/ntldr/winldr.h
index 38598e29f85..ee7c1fede7d 100644
--- a/boot/freeldr/freeldr/ntldr/winldr.h
+++ b/boot/freeldr/freeldr/ntldr/winldr.h
@@ -74,6 +74,9 @@ VOID ConvertConfigToVA(PCONFIGURATION_COMPONENT_DATA Start);
 
 // winldr.c
 extern BOOLEAN SosEnabled;
+#ifdef _M_IX86
+extern BOOLEAN PaeModeOn;
+#endif
 
 FORCEINLINE
 VOID