From 4d9d4bbd1a26e4305ab039ad9a395eee42735041 Mon Sep 17 00:00:00 2001
From: vit9696 <vit9696@users.noreply.github.com>
Date: Mon, 25 Mar 2019 19:39:32 +0300
Subject: [PATCH] OcAppleKernelLib: Fix number to string conversion

---
 Include/Library/OcStringLib.h               | 14 ++++++++
 Library/OcAppleKernelLib/PrelinkedContext.c | 36 +++----------------
 Library/OcStringLib/OcAsciiLib.c            | 39 +++++++++++++++++++++
 3 files changed, 58 insertions(+), 31 deletions(-)

diff --git a/Include/Library/OcStringLib.h b/Include/Library/OcStringLib.h
index 736c2cbe..0ec5de7a 100755
--- a/Include/Library/OcStringLib.h
+++ b/Include/Library/OcStringLib.h
@@ -336,4 +336,18 @@ TrimWhiteSpace (
   IN  CHAR16   *String
   );
 
+/**
+  Convert 64-bit unsigned integer to a nul-termianted hex string.
+
+  @param[out]  Buffer      Destination buffer.
+  @param[in]   BufferSize  Destination buffer size in bytes.
+  @param[in]   Value       Value to convert.
+**/
+BOOLEAN
+AsciiUint64ToLowerHex (
+  OUT CHAR8   *Buffer,
+  IN  UINT32  BufferSize,
+  IN  UINT64  Value
+  );
+
 #endif // OC_STRING_LIB_H_
diff --git a/Library/OcAppleKernelLib/PrelinkedContext.c b/Library/OcAppleKernelLib/PrelinkedContext.c
index 02628668..bc97d277 100644
--- a/Library/OcAppleKernelLib/PrelinkedContext.c
+++ b/Library/OcAppleKernelLib/PrelinkedContext.c
@@ -22,6 +22,7 @@
 #include <Library/MemoryAllocationLib.h>
 #include <Library/OcAppleKernelLib.h>
 #include <Library/OcMachoLib.h>
+#include <Library/OcStringLib.h>
 #include <Library/PrintLib.h>
 
 #include "PrelinkedInternal.h"
@@ -474,33 +475,6 @@ PrelinkedReserveKextSize (
   return EFI_SUCCESS;
 }
 
-STATIC
-BOOLEAN
-AsciiIntegerToLowerHex (
-  OUT CHAR8   *Buffer,
-  IN  UINT32  BufferSize,
-  IN  UINT64  Value
-  )
-{
-  UINT32 Index;
-  UINT8  Remainder;
-
-  for (Index = 0; Value != 0; Value /= 16, ++Index) {
-    if (Index >= BufferSize) {
-      return FALSE;
-    }
-
-    Remainder = (Value % 16);
-    if (Remainder < 10) {
-      Buffer[Index] = ('0' + Remainder);
-    } else {
-      Buffer[Index] = ('a' + (Remainder - 10));
-    }
-  }
-
-  return TRUE;
-}
-
 EFI_STATUS
 PrelinkedInjectKext (
   IN OUT PRELINKED_CONTEXT  *Context,
@@ -596,16 +570,16 @@ PrelinkedInjectKext (
   if (Executable != NULL) {
     Failed |= XmlNodeAppend (InfoPlistRoot, "key", NULL, PRELINK_INFO_EXECUTABLE_RELATIVE_PATH_KEY) == NULL;
     Failed |= XmlNodeAppend (InfoPlistRoot, "string", NULL, ExecutablePath) == NULL;
-    Failed |= !AsciiIntegerToLowerHex (ExecutableSourceAddrStr, sizeof (ExecutableSourceAddrStr), Context->PrelinkedLastAddress);
+    Failed |= !AsciiUint64ToLowerHex (ExecutableSourceAddrStr, sizeof (ExecutableSourceAddrStr), Context->PrelinkedLastAddress);
     Failed |= XmlNodeAppend (InfoPlistRoot, "key", NULL, PRELINK_INFO_EXECUTABLE_SOURCE_ADDR_KEY) == NULL;
     Failed |= XmlNodeAppend (InfoPlistRoot, "integer", PRELINK_INFO_INTEGER_ATTRIBUTES, ExecutableSourceAddrStr) == NULL;
-    Failed |= !AsciiIntegerToLowerHex (ExecutableLoadAddrStr, sizeof (ExecutableLoadAddrStr), Context->PrelinkedLastLoadAddress);
+    Failed |= !AsciiUint64ToLowerHex (ExecutableLoadAddrStr, sizeof (ExecutableLoadAddrStr), Context->PrelinkedLastLoadAddress);
     Failed |= XmlNodeAppend (InfoPlistRoot, "key", NULL, PRELINK_INFO_EXECUTABLE_LOAD_ADDR_KEY) == NULL;
     Failed |= XmlNodeAppend (InfoPlistRoot, "integer", PRELINK_INFO_INTEGER_ATTRIBUTES, ExecutableLoadAddrStr) == NULL;
-    Failed |= !AsciiIntegerToLowerHex (ExecutableSizeStr, sizeof (ExecutableSizeStr), AlignedExecutableSize);
+    Failed |= !AsciiUint64ToLowerHex (ExecutableSizeStr, sizeof (ExecutableSizeStr), AlignedExecutableSize);
     Failed |= XmlNodeAppend (InfoPlistRoot, "key", NULL, PRELINK_INFO_EXECUTABLE_SIZE_KEY) == NULL;
     Failed |= XmlNodeAppend (InfoPlistRoot, "integer", PRELINK_INFO_INTEGER_ATTRIBUTES, ExecutableSizeStr) == NULL;
-    Failed |= !AsciiIntegerToLowerHex (KmodInfoStr, sizeof (KmodInfoStr), KmodAddress);
+    Failed |= !AsciiUint64ToLowerHex (KmodInfoStr, sizeof (KmodInfoStr), KmodAddress);
     Failed |= XmlNodeAppend (InfoPlistRoot, "key", NULL, PRELINK_INFO_KMOD_INFO_KEY) == NULL;
     Failed |= XmlNodeAppend (InfoPlistRoot, "integer", PRELINK_INFO_INTEGER_ATTRIBUTES, KmodInfoStr) == NULL;  
   }
diff --git a/Library/OcStringLib/OcAsciiLib.c b/Library/OcStringLib/OcAsciiLib.c
index 88667564..162a4e79 100755
--- a/Library/OcStringLib/OcAsciiLib.c
+++ b/Library/OcStringLib/OcAsciiLib.c
@@ -336,3 +336,42 @@ AsciiTrimWhiteSpace (
   return String;
 }
 
+BOOLEAN
+AsciiUint64ToLowerHex (
+  OUT CHAR8   *Buffer,
+  IN  UINT32  BufferSize,
+  IN  UINT64  Value
+  )
+{
+  CONST UINT32  MaxShifts = (sizeof (UINT64) * 8) - 4;
+  UINT32        Index;
+  BOOLEAN       Printed;
+  UINT8         Curr;
+
+  if (BufferSize < 4) {
+    return FALSE;
+  }
+
+  *Buffer++   = '0';
+  *Buffer++   = 'x';
+
+  if (Value > 0) {
+    BufferSize -= 2;
+    for (Printed = FALSE, Index = MaxShifts; Index <= MaxShifts; Index -= 4) {
+      Curr     = (UINT8) ((Value >> Index) & 0xFU);
+      Printed |= Curr > 0;
+      if (Printed) {
+        *Buffer++ = "0123456789abcdef"[Curr];
+        if (--BufferSize == 0) {
+          return FALSE;
+        }
+      }
+    }
+  } else {
+    *Buffer++ = '0';
+  }
+
+  *Buffer++ = '\0';
+  return TRUE;
+}
+