[BOOT:BOOTLIB] Parse BCD GUID to application entry

BOOT/ENVIRON/INC/bootmgr.h

@@ -71,10 +71,14 @@ typedef struct {
     ULONG PlatformDataOffset;
 } BOOT_INPUT_PARAMETERS, *PBOOT_INPUT_PARAMETERS;
 
-#define BOOT_APPLICATION_ENTRY_SIGNATURE 0x544e4550415442
+#define BOOT_APPLICATION_ENTRY_SIGNATURE 0x544e4550415442 /* "BTAPENT" */
+
+#define BOOT_APPLICATION_ENTRY_BCD_IDENTIFIER_NOT_SET 0x01
 
 typedef struct {
     ULONGLONG Signature;
+    ULONG Attributes;
+    GUID BcdIdentifier;
 } BOOT_APPLICATION_ENTRY, *PBOOT_APPLICATION_ENTRY;
 
 #define BOOT_MEMORY_INFO_VERSION 1
@@ -87,7 +91,8 @@ typedef struct {
     ULONG BasePageOffset;
 } BOOT_MEMORY_INFO, *PBOOT_MEMORY_INFO;
 
-#define MEMORY_FLAG_CACHE_WB         0x08
+#define MEMORY_ATTRIBUTE_CACHE_WB 0x08
+
 #define MEMORY_TYPE_BOOT_APPLICATION 0xd0000002
 
 typedef struct {
@@ -96,7 +101,7 @@ typedef struct {
     ULONGLONG BasePage;
     ULONG Pages;
 
-    ULONG Flags;
+    ULONG Attributes;
     ULONG Type;
 } BOOT_MEMORY_DESCRIPTOR, *PBOOT_MEMORY_DESCRIPTOR;
 

BOOT/ENVIRON/LIB/EFI/efiinit.c

@@ -13,6 +13,9 @@ Abstract:
 
 --*/
 
+#include <ntrtl.h>
+#include <string.h>
+#include <wchar.h>
 #include "bootmgr.h"
 #include "efi.h"
 
@@ -30,7 +33,7 @@ EfiInitpCreateApplicationEntry (
     IN PWCHAR LoadOptions,
     IN ULONG LoadOptionsSize,
     OUT PULONG BufferUsed,
-    OUT PBOOT_DEVICE *Device
+    OUT PBOOT_DEVICE *BootDevice
     )
 
 /*++
@@ -57,7 +60,7 @@ Arguments:
 
     BufferUsed - Returns the amount of buffer space used by the routine.
 
-    Device - Returns a pointer to the device the application was loaded from.
+    BootDevice - Returns a pointer to the device the application was loaded from.
 
 Return Value:
 
@@ -66,19 +69,49 @@ Return Value:
 --*/
 
 {
+    PWCHAR BcdOptionString;
+    BOOLEAN BcdIdentifierSet;
+    UNICODE_STRING UnicodeString;
+
+    *BufferUsed = 0;
+    *BootDevice = NULL;
+    BcdIdentifierSet = FALSE;
+
     //
     // Require enough space for the application entry.
     //
     if (BufferSize < sizeof(BOOT_APPLICATION_ENTRY)) {
-        *BufferUsed = 0;
         return;
     }
 
+    //
+    // Terminate load options string.
+    //
+    LoadOptionsSize /= sizeof(WCHAR);
+    if (LoadOptionsSize != 0 && wcsnlen(LoadOptions, LoadOptionsSize) == LoadOptionsSize) {
+        LoadOptions[LoadOptionsSize - 1] = L'\0';
+    }
+
     //
     // Set up application entry structure.
     //
     RtlZeroMemory(Entry, sizeof(BOOT_APPLICATION_ENTRY));
     Entry->Signature = BOOT_APPLICATION_ENTRY_SIGNATURE;
+    *BufferUsed = sizeof(BOOT_APPLICATION_ENTRY);
+
+    //
+    // Parse BCD GUID if present.
+    //
+    if (LoadOptions != NULL && (BcdOptionString = wcsstr(LoadOptions, L"BCDOBJECT=")) != NULL) {
+        RtlInitUnicodeString(&UnicodeString, (PWCHAR)((PUCHAR)BcdOptionString + sizeof(L"BCDOBJECT=") - sizeof(UNICODE_NULL)));
+        if (NT_SUCCESS(RtlGUIDFromString(&UnicodeString, &Entry->BcdIdentifier))) {
+            BcdIdentifierSet = TRUE;
+        }
+    }
+
+    if (!BcdIdentifierSet) {
+        Entry->Attributes |= BOOT_APPLICATION_ENTRY_BCD_IDENTIFIER_NOT_SET;
+    }
 
     //
     // TODO: This routine is not fully implemented.
@@ -86,10 +119,6 @@ Return Value:
     (VOID)SystemTable;
     (VOID)DevicePath;
     (VOID)FilePath;
-    (VOID)LoadOptions;
-    (VOID)LoadOptionsSize;
-    (VOID)Device;
-    *BufferUsed = sizeof(BOOT_APPLICATION_ENTRY);
 }
 
 PBOOT_INPUT_PARAMETERS
@@ -192,7 +221,7 @@ Return Value:
     ScratchUsed += sizeof(BOOT_MEMORY_DESCRIPTOR);
     MemoryDescriptor->BasePage = (UINTN)InputParameters->ImageBase >> PAGE_SHIFT;
     MemoryDescriptor->Pages = ALIGN_UP(InputParameters->ImageSize, PAGE_SIZE) >> PAGE_SHIFT;
-    MemoryDescriptor->Flags = MEMORY_FLAG_CACHE_WB;
+    MemoryDescriptor->Attributes = MEMORY_ATTRIBUTE_CACHE_WB;
     MemoryDescriptor->Type = MEMORY_TYPE_BOOT_APPLICATION;
 
     //
@@ -243,6 +272,13 @@ Return Value:
     ScratchUsed += sizeof(BOOT_RETURN_DATA);
     ReturnData->Version = BOOT_RETURN_DATA_VERSION;
 
+    //
+    // Set and validate total size.
+    //
     InputParameters->Size = ScratchUsed;
+    if (InputParameters->Size > sizeof(EfiInitScratch)) {
+        return NULL;
+    }
+
     return InputParameters;
 }

BOOT/ENVIRON/LIB/rtl.c

@@ -1,84 +0,0 @@
-/*++
-
-Copyright (c) 2024, Quinn Stephens.
-Provided under the BSD 3-Clause license.
-
-Module Name:
-
-   rtl.c
-
-Abstract:
-
-    Runtime library routines.
-
---*/
-
-#include <nt.h>
-
-PVOID
-RtlCopyMemory (
-    PVOID Destination,
-    CONST PVOID Source,
-    ULONG Length
-    )
-
-/*++
-
-Routine Description:
-
-    Copies a block of memory from Source to Destination.
-
-Arguments:
-
-    Destination - the address to copy to.
-
-    Source - the address to copy from.
-
-    Length - the number of bytes to copy.
-
-Return Value:
-
-    Returns Destination.
-
---*/
-
-{
-    for (ULONG Index = 0; Index < Length; Index++) {
-        ((PCHAR)Destination)[Index] = ((PCHAR)Source)[Index];
-    }
-
-    return Destination;
-}
-
-
-PVOID
-RtlZeroMemory (
-    PVOID Destination,
-    ULONG Length
-    )
-
-/*++
-
-Routine Description:
-
-    Sets a block of memory to zero.
-
-Arguments:
-
-    Destination - the address to zero at.
-
-    Length - the number of bytes to set.
-
-Return Value:
-
-    Returns Destination.
-
---*/
-
-{
-    for (ULONG Index = 0; Index < Length; Index++) {
-        ((PCHAR)Destination)[Index] = 0;
-    }
-
-    return Destination;
-}