OCAB: Implement Mac OS X 10.4/10.5 relocation block support (#373)

Include/Acidanthera/Library/OcDeviceTreeLib.h

@@ -16,7 +16,25 @@
 #define OC_DEVICE_TREE_LIB_H
 
 //
-// Struct at the beginning of every loaded kext.
+// Device tree property name prefixes for loaded kexts or mkext.
+//
+#define DT_BOOTER_KEXT_PREFIX   "Driver-"
+#define DT_BOOTER_MKEXT_PREFIX  "DriversPackage-"
+
+//
+// Struct at the beginning of every loaded kext (10.4 and 10.5).
+// Pointers to every loaded kext (to this struct) are
+// properties Driver-<hex addr of DriverInfo> in DevTree /chosen/memory-map.
+//
+typedef struct DTBootxDriverInfo_ {
+  UINT32    PlistPhysAddr;
+  UINT32    PlistLength;
+  UINT32    ModuleAddress;
+  UINT32    ModuleLength;
+} DTBootxDriverInfo;
+
+//
+// Struct at the beginning of every loaded kext (10.6 and newer).
 // Pointers to every loaded kext (to this struct) are
 // properties Driver-<hex addr of DriverInfo> in DevTree /chosen/memory-map.
 //

Include/Apple/IndustryStandard/AppleBootArgs.h

@@ -111,9 +111,9 @@ typedef struct {
   UINT8           efiMode;              /* 32 = 32-bit, 64 = 64-bit */
   UINT8           __reserved1[3];
   UINT32          __reserved2[1];
-  UINT32          performanceDataStart; /* physical address of log */
+  UINT32          performanceDataStart; /* physical address of log, 10.6 and up */
   UINT32          performanceDataSize;
-  UINT64          efiRuntimeServicesVirtualPageStart; /* virtual address of defragmented runtime pages */
+  UINT64          efiRuntimeServicesVirtualPageStart; /* virtual address of defragmented runtime pages, 10.6 and up */
   UINT32          __reserved3[2];
 } BootArgs1;
 

Library/OcAfterBootCompatLib/BootCompatInternal.h

@@ -64,20 +64,30 @@
 #define KERNEL_HIB_VADDR  ((UINTN) (0xFFFFFF8000100000ULL & MAX_UINTN))
 
 /**
-  Kernel __TEXT segment virtual address.
+  Kernel __TEXT segment virtual address (macOS 10.6 and higher).
 **/
 #define KERNEL_TEXT_VADDR  ((UINTN) (0xFFFFFF8000200000ULL & MAX_UINTN))
 
+/**
+  Kernel __TEXT segment virtual address (macOS 10.4 and 10.5).
+**/
+#define KERNEL_TEXT_VADDR_LEGACY  0x111000
+
 /**
   Kernel physical base address.
 **/
 #define KERNEL_BASE_PADDR  ((UINT32) (KERNEL_HIB_VADDR & MAX_UINT32))
 
 /**
-  Kernel physical base address.
+  Kernel __TEXT physical base address (macOS 10.6 and higher).
 **/
 #define KERNEL_TEXT_PADDR  ((UINT32) (KERNEL_TEXT_VADDR & MAX_UINT32))
 
+/**
+  Kernel __TEXT physical base address (macOS 10.4 and 10.5).
+**/
+#define KERNEL_TEXT_PADDR_LEGACY  (KERNEL_TEXT_VADDR_LEGACY)
+
 /**
   Slide offset per slide entry
 **/
@@ -355,6 +365,10 @@ typedef struct KERNEL_SUPPORT_STATE_ {
   /// This value should match ksize in XNU BootArgs.
   ///
   UINTN                   RelocationBlockUsed;
+  ///
+  /// Relocation block is being used on macOS 10.4 or 10.5.
+  ///
+  BOOLEAN                 RelocationBlockLegacy;
 } KERNEL_SUPPORT_STATE;
 
 /**
@@ -413,7 +427,7 @@ typedef struct SLIDE_SUPPORT_STATE_ {
 **/
 typedef struct BOOT_COMPAT_CONTEXT_ {
   ///
-  /// Apple Coot Compatibility settings.
+  /// Apple Boot Compatibility settings.
   ///
   OC_ABC_SETTINGS            Settings;
   ///

Library/OcAfterBootCompatLib/KernelSupport.c

@@ -384,10 +384,10 @@ AppleMapPrepareForBooting (
     }
   }
 
-  if (BootCompat->KernelState.RelocationBlock != 0) {
+  if ((BootCompat->KernelState.RelocationBlock != 0) && !BootCompat->KernelState.RelocationBlockLegacy) {
     //
-    // When using Relocation Block EfiBoot will not virtualize the addresses since they
-    // cannot be mapped 1:1 due to any region from the relocation block being outside
+    // When using Relocation Block, EfiBoot on macOS 10.6 and newer will not virtualize the addresses
+    // since they cannot be mapped 1:1 due to any region from the relocation block being outside
     // of static XNU vaddr to paddr mapping. This causes a clean early exit in their
     // SetVirtualAddressMap calling routine avoiding gRT->SetVirtualAddressMap.
     //
@@ -687,7 +687,10 @@ AppleMapPrepareMemState (
   IN     EFI_MEMORY_DESCRIPTOR  *MemoryMap
   )
 {
-  EFI_STATUS  Status;
+  EFI_STATUS             Status;
+  UINTN                  NumEntries;
+  UINTN                  Index;
+  EFI_MEMORY_DESCRIPTOR  *Desc;
 
   //
   // Protect RT areas from relocation by marking then MemMapIO.
@@ -703,6 +706,25 @@ AppleMapPrepareMemState (
       );
   }
 
+  //
+  // macOS 10.4 and 10.5 always call SetVirtualAddressMap, even when using a relocation block.
+  // Perform adjustment of virtual addresses here to their final positions.
+  //
+  if (BootCompat->KernelState.RelocationBlockLegacy) {
+    Desc       = MemoryMap;
+    NumEntries = MemoryMapSize / DescriptorSize;
+
+    for (Index = 0; Index < NumEntries; ++Index) {
+      if (  (Desc->VirtualStart >= BootCompat->KernelState.RelocationBlock + BootCompat->KernelState.RelocationBlockUsed)
+         && (Desc->VirtualStart < BootCompat->KernelState.RelocationBlock + ESTIMATED_KERNEL_SIZE))
+      {
+        Desc->VirtualStart -= BootCompat->KernelState.RelocationBlock - KERNEL_BASE_PADDR;
+      }
+
+      Desc = NEXT_MEMORY_DESCRIPTOR (Desc, DescriptorSize);
+    }
+  }
+
   //
   // Virtualize RT services with all needed fixes.
   //

Library/OcAfterBootCompatLib/RelocationBlock.c

@@ -59,16 +59,17 @@ AppleRelocationAllocatePages (
   // this quirk anyway due to AllocatePages in AllocateAddress mode Address pointer
   // no longer being reread after the allocation in EfiBoot.
   //
-  if ((*Memory == KERNEL_TEXT_PADDR) && (BootCompat->KernelState.RelocationBlock == 0)) {
-    BootCompat->KernelState.RelocationBlock = BASE_4GB;
-    Status                                  = OcAllocatePagesFromTop (
-                                                EfiLoaderData,
-                                                EFI_SIZE_TO_PAGES (EssentialSize),
-                                                &BootCompat->KernelState.RelocationBlock,
-                                                GetMemoryMap,
-                                                AllocatePages,
-                                                NULL
-                                                );
+  if (((*Memory == KERNEL_TEXT_PADDR) || (*Memory == KERNEL_TEXT_PADDR_LEGACY)) && (BootCompat->KernelState.RelocationBlock == 0)) {
+    BootCompat->KernelState.RelocationBlock       = BASE_4GB;
+    BootCompat->KernelState.RelocationBlockLegacy = *Memory == KERNEL_TEXT_PADDR_LEGACY;
+    Status                                        = OcAllocatePagesFromTop (
+                                                      EfiLoaderData,
+                                                      EFI_SIZE_TO_PAGES (EssentialSize),
+                                                      &BootCompat->KernelState.RelocationBlock,
+                                                      GetMemoryMap,
+                                                      AllocatePages,
+                                                      NULL
+                                                      );
     if (EFI_ERROR (Status)) {
       DEBUG ((
         DEBUG_INFO,
@@ -82,6 +83,18 @@ AppleRelocationAllocatePages (
     BootCompat->KernelState.RelocationBlockUsed = 0;
   }
 
+  //
+  // macOS 10.4 and 10.5 do not request original lower addresses when allocating additional kernel structures (boot args, MKEXT, etc).
+  // If such addresses are requested within the range of our allocated relocation block, adjust them.
+  //
+  if (  (BootCompat->KernelState.RelocationBlock != 0)
+     &&  BootCompat->KernelState.RelocationBlockLegacy
+     && (*Memory > BootCompat->KernelState.RelocationBlock)
+     && (*Memory < BootCompat->KernelState.RelocationBlock + EssentialSize))
+  {
+    *Memory -= (BootCompat->KernelState.RelocationBlock - KERNEL_BASE_PADDR);
+  }
+
   //
   // Not our allocation.
   //
@@ -130,8 +143,9 @@ AppleRelocationRelease (
                   EFI_SIZE_TO_PAGES (EssentialSize)
                   );
 
-  BootCompat->KernelState.RelocationBlock     = 0;
-  BootCompat->KernelState.RelocationBlockUsed = 0;
+  BootCompat->KernelState.RelocationBlock       = 0;
+  BootCompat->KernelState.RelocationBlockUsed   = 0;
+  BootCompat->KernelState.RelocationBlockLegacy = FALSE;
 
   return Status;
 }
@@ -247,6 +261,15 @@ AppleRelocationRebase (
   DTMemMapEntry             *PropValue;
   OpaqueDTPropertyIterator  OPropIter;
   DTPropertyIterator        PropIter;
+  DTBooterKextFileInfo      *BooterKextFileInfo;
+  DTBootxDriverInfo         *BootxDriverInfo;
+  UINT32                    MemoryMapSize;
+  UINT32                    DescriptorSize;
+  EFI_MEMORY_DESCRIPTOR     *MemoryMap;
+  UINT32                    NumEntries;
+  UINT32                    Index;
+  EFI_MEMORY_DESCRIPTOR     *Desc;
+  EFI_PHYSICAL_ADDRESS      PrevDescAddress;
   UINT32                    RelocDiff;
 
   PropIter = &OPropIter;
@@ -282,6 +305,25 @@ AppleRelocationRebase (
           continue;
         }
 
+        //
+        // Fix Driver-* entries for kexts used during a cacheless boot.
+        //
+        if (AsciiStrnCmp (PropName, DT_BOOTER_KEXT_PREFIX, L_STR_LEN (DT_BOOTER_KEXT_PREFIX)) == 0) {
+          //
+          // 10.6 and newer use a different format from 10.4 and 10.5.
+          //
+          if (!BootCompat->KernelState.RelocationBlockLegacy) {
+            BooterKextFileInfo                      = (DTBooterKextFileInfo *)((UINTN)PropValue->Address);
+            BooterKextFileInfo->InfoDictPhysAddr   -= RelocDiff;
+            BooterKextFileInfo->ExecutablePhysAddr -= RelocDiff;
+            BooterKextFileInfo->BundlePathPhysAddr -= RelocDiff;
+          } else {
+            BootxDriverInfo                 = (DTBootxDriverInfo *)((UINTN)PropValue->Address);
+            BootxDriverInfo->PlistPhysAddr -= RelocDiff;
+            BootxDriverInfo->ModuleAddress -= RelocDiff;
+          }
+        }
+
         //
         // Patch the addresses up.
         //
@@ -290,9 +332,40 @@ AppleRelocationRebase (
     }
   }
 
+  //
+  // On macOS 10.4 and 10.5, EfiBoot has already set the system table address to the correct virtual one.
+  // The memory map also contains additional trashed entries that must be removed, this seems to occur on Macs as well.
+  //
+  // On macOS 10.6 and newer, we need to adjust it like the others.
+  //
+  if (!BootCompat->KernelState.RelocationBlockLegacy) {
+    *BA->SystemTableP -= RelocDiff;
+  } else {
+    MemoryMapSize  = *BA->MemoryMapSize;
+    DescriptorSize = *BA->MemoryMapDescriptorSize;
+    MemoryMap      = (EFI_MEMORY_DESCRIPTOR *)(UINTN)*BA->MemoryMap;
+
+    Desc            = MemoryMap;
+    PrevDescAddress = Desc->PhysicalStart;
+    NumEntries      = MemoryMapSize / DescriptorSize;
+
+    //
+    // Locate end of valid memory map. It is assumed that the entries are
+    // sorted smallest to largest (performed by AllowRelocationBlock or RebuildAppleMemoryMap).
+    //
+    for (Index = 0; Index < NumEntries; ++Index) {
+      if (Desc->PhysicalStart < PrevDescAddress) {
+        *BA->MemoryMapSize -= (DescriptorSize * (NumEntries - Index));
+        break;
+      }
+
+      PrevDescAddress = Desc->PhysicalStart;
+      Desc            = NEXT_MEMORY_DESCRIPTOR (Desc, DescriptorSize);
+    }
+  }
+
   *BA->MemoryMap         -= RelocDiff;
   *BA->KernelAddrP       -= RelocDiff;
-  *BA->SystemTableP      -= RelocDiff;
   *BA->RuntimeServicesPG -= EFI_SIZE_TO_PAGES (RelocDiff);
   //
   // Note, this one does not seem to be used by XNU but we set it anyway.

Library/OcAfterBootCompatLib/ServiceOverrides.c

@@ -674,6 +674,11 @@ OcGetMemoryMap (
         MemoryMap,
         *DescriptorSize
         );
+    } else if (BootCompat->Settings.AllowRelocationBlock) {
+      //
+      // A sorted memory map is required when using a relocation block.
+      //
+      OcSortMemoryMap (*MemoryMapSize, MemoryMap, *DescriptorSize);
     }
 
     //