From 2755e378483a072efab051c7730e5240161ec393 Mon Sep 17 00:00:00 2001
From: Timo Kreuzer <timo.kreuzer@reactos.org>
Date: Mon, 31 Dec 2012 10:08:34 +0000
Subject: [PATCH] [FREELDR] Implement MmCheckFreeldrImageFile() to check that
 freeldr was properly compiled and loaded.

svn path=/trunk/; revision=58066
---
 .../boot/freeldr/freeldr/arch/i386/i386bug.c  |  8 ----
 reactos/boot/freeldr/freeldr/debug.c          | 10 ++++
 .../freeldr/include/arch/pc/x86common.h       |  1 +
 reactos/boot/freeldr/freeldr/include/debug.h  | 15 ++++++
 reactos/boot/freeldr/freeldr/include/mm.h     |  7 +++
 reactos/boot/freeldr/freeldr/mm/meminit.c     | 47 +++++++++++++++++++
 6 files changed, 80 insertions(+), 8 deletions(-)

diff --git a/reactos/boot/freeldr/freeldr/arch/i386/i386bug.c b/reactos/boot/freeldr/freeldr/arch/i386/i386bug.c
index 260e39dd630..4ea6876b37f 100644
--- a/reactos/boot/freeldr/freeldr/arch/i386/i386bug.c
+++ b/reactos/boot/freeldr/freeldr/arch/i386/i386bug.c
@@ -171,14 +171,6 @@ i386PrintExceptionText(ULONG TrapIndex, PKTRAP_FRAME TrapFrame, PKSPECIAL_REGIST
               InstructionPointer[6], InstructionPointer[7]);
 }
 
-char *BugCodeStrings[] =
-{
-    "TEST_BUGCHECK",
-    "MISSING_HARDWARE_REQUIREMENTS",
-};
-
-ULONG_PTR BugCheckInfo[5];
-
 void
 NTAPI
 FrLdrBugCheckEx(
diff --git a/reactos/boot/freeldr/freeldr/debug.c b/reactos/boot/freeldr/freeldr/debug.c
index 21b78ca2918..5ac8e10fbd0 100644
--- a/reactos/boot/freeldr/freeldr/debug.c
+++ b/reactos/boot/freeldr/freeldr/debug.c
@@ -427,3 +427,13 @@ RtlAssert(IN PVOID FailedAssertion,
 
    DbgBreakPoint();
 }
+
+char *BugCodeStrings[] =
+{
+    "TEST_BUGCHECK",
+    "MISSING_HARDWARE_REQUIREMENTS",
+    "FREELDR_IMAGE_CORRUPTION",
+};
+
+ULONG_PTR BugCheckInfo[5];
+
diff --git a/reactos/boot/freeldr/freeldr/include/arch/pc/x86common.h b/reactos/boot/freeldr/freeldr/include/arch/pc/x86common.h
index 91f8c420a0a..e681390bc61 100644
--- a/reactos/boot/freeldr/freeldr/include/arch/pc/x86common.h
+++ b/reactos/boot/freeldr/freeldr/include/arch/pc/x86common.h
@@ -23,6 +23,7 @@
 #define BIOSCALLBUFSEGMENT (BIOSCALLBUFFER/16) /* Buffer to store temporary data for any Int386() call */
 #define BIOSCALLBUFOFFSET   HEX(0000) /* Buffer to store temporary data for any Int386() call */
 #define BIOSCALLBUFSIZE     PAGE_SIZE /* max is sizeof(VESA_SVGA_INFO) = 512 */
+#define MAX_FREELDR_PE_SIZE (DISKREADBUFFER - FREELDR_PE_BASE)
 
 /* These addresses specify the realmode "BSS section" layout */
 #define BSS_RealModeEntry        (BSS_START +  0)
diff --git a/reactos/boot/freeldr/freeldr/include/debug.h b/reactos/boot/freeldr/freeldr/include/debug.h
index 16d04cc1780..7ab94d0491f 100644
--- a/reactos/boot/freeldr/freeldr/include/debug.h
+++ b/reactos/boot/freeldr/freeldr/include/debug.h
@@ -120,4 +120,19 @@ void	MEMORY_WRITE_BREAKPOINT4(unsigned long addr);
 
 #endif // DBG
 
+void
+NTAPI
+FrLdrBugCheck(ULONG BugCode);
+
+/* Bugcheck codes */
+enum _FRLDR_BUGCHECK_CODES
+{
+    TEST_BUGCHECK,
+    MISSING_HARDWARE_REQUIREMENTS,
+    FREELDR_IMAGE_CORRUPTION,
+};
+
+extern char *BugCodeStrings[];
+extern ULONG_PTR BugCheckInfo[5];
+
 #endif // defined __DEBUG_H
diff --git a/reactos/boot/freeldr/freeldr/include/mm.h b/reactos/boot/freeldr/freeldr/include/mm.h
index a453a284770..7b6ed61566a 100644
--- a/reactos/boot/freeldr/freeldr/include/mm.h
+++ b/reactos/boot/freeldr/freeldr/include/mm.h
@@ -19,6 +19,13 @@
 
 #pragma once
 
+extern char __ImageBase;
+#ifdef __GNUC__
+#define FREELDR_SECTION_COUNT 3
+#else
+#define FREELDR_SECTION_COUNT 1
+#endif
+
 typedef struct _FREELDR_MEMORY_DESCRIPTOR
 {
     TYPE_OF_MEMORY MemoryType;
diff --git a/reactos/boot/freeldr/freeldr/mm/meminit.c b/reactos/boot/freeldr/freeldr/mm/meminit.c
index 7794f6f1639..5a8a25d4d05 100644
--- a/reactos/boot/freeldr/freeldr/mm/meminit.c
+++ b/reactos/boot/freeldr/freeldr/mm/meminit.c
@@ -163,6 +163,47 @@ ArcGetMemoryDescriptor(const FREELDR_MEMORY_DESCRIPTOR* Current)
 }
 
 
+BOOLEAN
+MmCheckFreeldrImageFile()
+{
+    PIMAGE_NT_HEADERS NtHeaders;
+    PIMAGE_FILE_HEADER FileHeader;
+    PIMAGE_OPTIONAL_HEADER OptionalHeader;
+
+    /* Get the NT headers */
+    NtHeaders = RtlImageNtHeader(&__ImageBase);
+    if (!NtHeaders)
+    {
+        ERR("Coult not get NtHeaders!\n");
+        return FALSE;
+    }
+
+    /* Check the file header */
+    FileHeader = &NtHeaders->FileHeader;
+    if ((FileHeader->Machine != IMAGE_FILE_MACHINE_NATIVE) ||
+        (FileHeader->NumberOfSections != FREELDR_SECTION_COUNT) ||
+        (FileHeader->PointerToSymbolTable != 0) ||
+        (FileHeader->NumberOfSymbols != 0) ||
+        (FileHeader->NumberOfSymbols != 0) ||
+        (FileHeader->SizeOfOptionalHeader != 0xE0))
+    {
+        return FALSE;
+    }
+
+    /* Check the optional header */
+    OptionalHeader = &NtHeaders->OptionalHeader;
+    if ((OptionalHeader->Magic != IMAGE_NT_OPTIONAL_HDR_MAGIC) ||
+        (OptionalHeader->Subsystem != 1) || // native
+        (OptionalHeader->ImageBase != FREELDR_PE_BASE) ||
+        (OptionalHeader->SizeOfImage > MAX_FREELDR_PE_SIZE) ||
+        (OptionalHeader->SectionAlignment != OptionalHeader->FileAlignment))
+    {
+        return FALSE;
+    }
+
+    return TRUE;
+}
+
 BOOLEAN MmInitializeMemoryManager(VOID)
 {
 #if DBG
@@ -171,6 +212,12 @@ BOOLEAN MmInitializeMemoryManager(VOID)
 
 	TRACE("Initializing Memory Manager.\n");
 
+	/* Check the freeldr binary */
+	if (!MmCheckFreeldrImageFile())
+	{
+		FrLdrBugCheck(FREELDR_IMAGE_CORRUPTION);
+	}
+
     BiosMemoryMap = MachVtbl.GetMemoryMap(&BiosMemoryMapEntryCount);
 
 #if DBG