xnu-4570.20.62.tar.gz

[apple/xnu.git] / libsa / bootstrap.cpp

diff --git a/libsa/bootstrap.cpp b/libsa/bootstrap.cpp
index 02e5694d06241f4ddc42ad5f6f4dbd0f5bf9638f..80a7508f3148533fceb978e0aec370f0fbbfe7d9 100644 (file)
--- a/libsa/bootstrap.cpp
+++ b/libsa/bootstrap.cpp
@@ -29,6 +29,10 @@ extern "C" {
 #include <mach/kmod.h>
 #include <libkern/kernel_mach_header.h>
 #include <libkern/prelink.h>
 #include <mach/kmod.h>
 #include <libkern/kernel_mach_header.h>
 #include <libkern/prelink.h>

+
+#if CONFIG_EMBEDDED
+extern uuid_t kernelcache_uuid;
+#endif

 }
 
 #include <libkern/version.h>
 }
 
 #include <libkern/version.h>


@@ -111,6 +115,26 @@ static const char * sKernelComponentNames[] = {
    NULL
 };
 
    NULL
 };
 

+static int __whereIsAddr(vm_offset_t theAddr, unsigned long * segSizes, vm_offset_t *segAddrs, int segCount );
+
+#define PLK_SEGMENTS 12
+
+static const char * plk_segNames[] = {
+    "__TEXT",
+    "__TEXT_EXEC",
+    "__DATA",
+    "__DATA_CONST",
+    "__LINKEDIT",
+    "__PRELINK_TEXT",
+    "__PLK_TEXT_EXEC",
+    "__PRELINK_DATA",
+    "__PLK_DATA_CONST",
+    "__PLK_LLVM_COV",
+    "__PLK_LINKEDIT",
+    "__PRELINK_INFO",
+    NULL
+};
+

 #if PRAGMA_MARK
 #pragma mark KLDBootstrap Class
 #endif
 #if PRAGMA_MARK
 #pragma mark KLDBootstrap Class
 #endif


@@ -206,6 +230,11 @@ KLDBootstrap::readStartupExtensions(void)
     return;
 }
 
     return;
 }
 

+typedef struct kaslrPackedOffsets {
+    uint32_t   count;              /* number of offsets */
+    uint32_t   offsetsArray[];     /* offsets to slide */
+} kaslrPackedOffsets;
+

 /*********************************************************************
 *********************************************************************/
 void
 /*********************************************************************
 *********************************************************************/
 void


@@ -217,6 +246,9 @@ KLDBootstrap::readPrelinkedExtensions(
     OSDictionary              * prelinkInfoDict         = NULL;  // do not release
     OSString                  * errorString             = NULL;  // must release
     OSKext                    * theKernel               = NULL;  // must release
     OSDictionary              * prelinkInfoDict         = NULL;  // do not release
     OSString                  * errorString             = NULL;  // must release
     OSKext                    * theKernel               = NULL;  // must release

+#if CONFIG_EMBEDDED
+    OSData                    * kernelcacheUUID         = NULL;  // do not release
+#endif

 
     kernel_segment_command_t  * prelinkTextSegment      = NULL;  // see code
     kernel_segment_command_t  * prelinkInfoSegment      = NULL;  // see code
 
     kernel_segment_command_t  * prelinkTextSegment      = NULL;  // see code
     kernel_segment_command_t  * prelinkInfoSegment      = NULL;  // see code


@@ -239,6 +271,9 @@ KLDBootstrap::readPrelinkedExtensions(
     bool                        developerDevice;
     bool                        dontLoad;
 #endif
     bool                        developerDevice;
     bool                        dontLoad;
 #endif

+    OSData                     * kaslrOffsets = NULL;
+    unsigned long               plk_segSizes[PLK_SEGMENTS];
+    vm_offset_t                 plk_segAddrs[PLK_SEGMENTS];

 
     OSKextLog(/* kext */ NULL,
         kOSKextLogProgressLevel |
 
     OSKextLog(/* kext */ NULL,
         kOSKextLogProgressLevel |


@@ -300,6 +335,14 @@ KLDBootstrap::readPrelinkedExtensions(
     prelinkData = (void *) prelinkTextSegment->vmaddr;
     prelinkLength = prelinkTextSegment->vmsize;
 
     prelinkData = (void *) prelinkTextSegment->vmaddr;
     prelinkLength = prelinkTextSegment->vmsize;
 

+    /* build arrays of plk info for later use */
+    const char ** segNamePtr;
+
+    for (segNamePtr = &plk_segNames[0], i = 0; *segNamePtr && i < PLK_SEGMENTS; segNamePtr++, i++) {
+        plk_segSizes[i] = 0;
+        plk_segAddrs[i] = (vm_offset_t)getsegdatafromheader(&_mh_execute_header, *segNamePtr, &plk_segSizes[i]);
+    }
+

 
    /* Unserialize the info dictionary from the prelink info section.
     */
 
    /* Unserialize the info dictionary from the prelink info section.
     */


@@ -331,6 +374,20 @@ KLDBootstrap::readPrelinkedExtensions(
     ramDiskBoot = IORamDiskBSDRoot();
 #endif /* NO_KEXTD */
 
     ramDiskBoot = IORamDiskBSDRoot();
 #endif /* NO_KEXTD */
 

+#if CONFIG_EMBEDDED
+    /* Copy in the kernelcache UUID */
+    kernelcacheUUID = OSDynamicCast(OSData,
+        prelinkInfoDict->getObject(kPrelinkInfoKCIDKey));
+    if (!kernelcacheUUID) {
+       bzero(&kernelcache_uuid, sizeof(kernelcache_uuid));
+    } else if (kernelcacheUUID->getLength() != sizeof(kernelcache_uuid)) {
+        panic("kernelcacheUUID length is %d, expected %lu", kernelcacheUUID->getLength(),
+            sizeof(kernelcache_uuid));
+    } else {
+        memcpy((void *)&kernelcache_uuid, (void *)kernelcacheUUID->getBytesNoCopy(), kernelcacheUUID->getLength());
+    }
+#endif /* CONFIG_EMBEDDED */
+

     infoDictArray = OSDynamicCast(OSArray, 
         prelinkInfoDict->getObject(kPrelinkInfoDictionaryKey));
     if (!infoDictArray) {
     infoDictArray = OSDynamicCast(OSArray, 
         prelinkInfoDict->getObject(kPrelinkInfoDictionaryKey));
     if (!infoDictArray) {


@@ -339,10 +396,15 @@ KLDBootstrap::readPrelinkedExtensions(
         goto finish;
     }
     
         goto finish;
     }
     

+    /* kaslrOffsets are available use them to slide local relocations */
+    kaslrOffsets = OSDynamicCast(OSData,
+                                 prelinkInfoDict->getObject(kPrelinkLinkKASLROffsetsKey));
+        

     /* Create dictionary of excluded kexts
      */
     /* Create dictionary of excluded kexts
      */

+#ifndef CONFIG_EMBEDDED

     OSKext::createExcludeListFromPrelinkInfo(infoDictArray);
     OSKext::createExcludeListFromPrelinkInfo(infoDictArray);

-
+#endif

     /* Create OSKext objects for each info dictionary. 
      */
     for (i = 0; i < infoDictArray->getCount(); ++i) {
     /* Create OSKext objects for each info dictionary. 
      */
     for (i = 0; i < infoDictArray->getCount(); ++i) {


@@ -376,7 +438,7 @@ KLDBootstrap::readPrelinkedExtensions(
             if (ramDiskOnlyBool == kOSBooleanTrue) {
                 dontLoad = true;
             }
             if (ramDiskOnlyBool == kOSBooleanTrue) {
                 dontLoad = true;
             }

-       }
+        }

 
         if (dontLoad == true) {
             OSString *bundleID = OSDynamicCast(OSString,
 
         if (dontLoad == true) {
             OSString *bundleID = OSDynamicCast(OSString,


@@ -391,7 +453,13 @@ KLDBootstrap::readPrelinkedExtensions(
             OSNumber *lengthNum = OSDynamicCast(OSNumber,
                 infoDict->getObject(kPrelinkExecutableSizeKey));
             if (addressNum && lengthNum) {
             OSNumber *lengthNum = OSDynamicCast(OSNumber,
                 infoDict->getObject(kPrelinkExecutableSizeKey));
             if (addressNum && lengthNum) {

+#if __arm__ || __arm64__
+                vm_offset_t data = (vm_offset_t) ((addressNum->unsigned64BitValue()) + vm_kernel_slide);
+                vm_size_t length = (vm_size_t) (lengthNum->unsigned32BitValue());
+                ml_static_mfree(data, length);
+#else

 #error Pick the right way to free prelinked data on this arch
 #error Pick the right way to free prelinked data on this arch

+#endif

             }
 
             infoDictArray->removeObject(i--);
             }
 
             infoDictArray->removeObject(i--);


@@ -403,10 +471,47 @@ KLDBootstrap::readPrelinkedExtensions(
         * kext system keeps them around until explicitly removed.
         * Any creation/registration failures are already logged for us.
         */
         * kext system keeps them around until explicitly removed.
         * Any creation/registration failures are already logged for us.
         */

-        OSKext * newKext = OSKext::withPrelinkedInfoDict(infoDict);
+        OSKext * newKext = OSKext::withPrelinkedInfoDict(infoDict, (kaslrOffsets ? TRUE : FALSE));

         OSSafeReleaseNULL(newKext);
     }
         OSSafeReleaseNULL(newKext);
     }

-    
+
+    /* slide kxld relocations */
+    if (kaslrOffsets && vm_kernel_slide > 0) {
+           int slidKextAddrCount = 0;
+           int badSlideAddr = 0;
+           int badSlideTarget = 0;
+
+        kaslrPackedOffsets * myOffsets = NULL;
+           myOffsets = (kaslrPackedOffsets *) kaslrOffsets->getBytesNoCopy();
+
+           for (uint32_t j = 0; j < myOffsets->count; j++) {
+
+                   uint64_t        slideOffset = (uint64_t) myOffsets->offsetsArray[j];
+                   uintptr_t *     slideAddr = (uintptr_t *) ((uint64_t)prelinkData + slideOffset);
+                   int             slideAddrSegIndex = -1;
+                   int             addrToSlideSegIndex = -1;
+
+                   slideAddrSegIndex = __whereIsAddr( (vm_offset_t)slideAddr, &plk_segSizes[0], &plk_segAddrs[0], PLK_SEGMENTS );
+                   if (slideAddrSegIndex >= 0) {
+                           addrToSlideSegIndex = __whereIsAddr( (vm_offset_t)(*slideAddr + vm_kernel_slide), &plk_segSizes[0], &plk_segAddrs[0], PLK_SEGMENTS );
+                           if (addrToSlideSegIndex < 0) {
+                                   badSlideTarget++;
+                                   continue;
+                           }
+                   }
+                   else {
+                           badSlideAddr++;
+                           continue;
+                   }
+
+                   slidKextAddrCount++;
+                   *(slideAddr) += vm_kernel_slide;
+           } // for ...
+
+           /* All kexts are now slid, set VM protections for them */
+           OSKext::setAllVMAttributes();
+    }
+

    /* Store the number of prelinked kexts in the registry so we can tell
     * when the system has been started from a prelinked kernel.
     */
    /* Store the number of prelinked kexts in the registry so we can tell
     * when the system has been started from a prelinked kernel.
     */


@@ -420,7 +525,7 @@ KLDBootstrap::readPrelinkedExtensions(
     if (prelinkCountObj) {
         registryRoot->setProperty(kOSPrelinkKextCountKey, prelinkCountObj);
     }
     if (prelinkCountObj) {
         registryRoot->setProperty(kOSPrelinkKextCountKey, prelinkCountObj);
     }

-
+    

     OSKextLog(/* kext */ NULL,
         kOSKextLogProgressLevel |
         kOSKextLogGeneralFlag | kOSKextLogKextBookkeepingFlag |
     OSKextLog(/* kext */ NULL,
         kOSKextLogProgressLevel |
         kOSKextLogGeneralFlag | kOSKextLogKextBookkeepingFlag |


@@ -445,13 +550,30 @@ KLDBootstrap::readPrelinkedExtensions(
     }
 
 finish:
     }
 
 finish:

-    OSSafeRelease(errorString);
-    OSSafeRelease(parsedXML);
-    OSSafeRelease(theKernel);
-    OSSafeRelease(prelinkCountObj);
+    OSSafeReleaseNULL(errorString);
+    OSSafeReleaseNULL(parsedXML);
+    OSSafeReleaseNULL(theKernel);
+    OSSafeReleaseNULL(prelinkCountObj);

     return;
 }
 
     return;
 }
 

+static int __whereIsAddr(vm_offset_t theAddr, unsigned long * segSizes, vm_offset_t *segAddrs, int segCount)
+{
+       int i;
+
+       for (i = 0; i < segCount; i++) {
+               vm_offset_t         myAddr = *(segAddrs + i);
+               unsigned long       mySize = *(segSizes + i);
+
+               if (theAddr >= myAddr && theAddr < (myAddr + mySize)) {
+                       return i;
+               }
+       }
+
+       return -1;
+}
+
+

 /*********************************************************************
 *********************************************************************/
 #define BOOTER_KEXT_PREFIX   "Driver-"
 /*********************************************************************
 *********************************************************************/
 #define BOOTER_KEXT_PREFIX   "Driver-"


@@ -510,7 +632,9 @@ KLDBootstrap::readBooterExtensions(void)
 
     /* Create dictionary of excluded kexts
      */
 
     /* Create dictionary of excluded kexts
      */

+#ifndef CONFIG_EMBEDDED

     OSKext::createExcludeListFromBooterData(propertyDict, keyIterator);
     OSKext::createExcludeListFromBooterData(propertyDict, keyIterator);

+#endif

     keyIterator->reset();
 
     while ( ( deviceTreeName =
     keyIterator->reset();
 
     while ( ( deviceTreeName =


@@ -582,7 +706,7 @@ KLDBootstrap::readBooterExtensions(void)
          * Any creation/registration failures are already logged for us.
          */
         OSKext * newKext = OSKext::withBooterData(deviceTreeName, booterData);
          * Any creation/registration failures are already logged for us.
          */
         OSKext * newKext = OSKext::withBooterData(deviceTreeName, booterData);

-        OSSafeRelease(newKext);
+        OSSafeReleaseNULL(newKext);

 
         booterMemoryMap->removeProperty(deviceTreeName);
 
 
         booterMemoryMap->removeProperty(deviceTreeName);
 


@@ -590,11 +714,11 @@ KLDBootstrap::readBooterExtensions(void)
 
 finish:
 
 
 finish:
 

-    OSSafeRelease(booterMemoryMap);
-    OSSafeRelease(propertyDict);
-    OSSafeRelease(keyIterator);
-    OSSafeRelease(booterData);
-    OSSafeRelease(aKext);
+    OSSafeReleaseNULL(booterMemoryMap);
+    OSSafeReleaseNULL(propertyDict);
+    OSSafeReleaseNULL(keyIterator);
+    OSSafeReleaseNULL(booterData);
+    OSSafeReleaseNULL(aKext);

     return;
 }
 
     return;
 }
 


@@ -660,8 +784,8 @@ KLDBootstrap::loadSecurityExtensions(void)
     }
 
 finish:
     }
 
 finish:

-    OSSafeRelease(keyIterator);
-    OSSafeRelease(extensionsDict);
+    OSSafeReleaseNULL(keyIterator);
+    OSSafeReleaseNULL(extensionsDict);

 
     return;
 }
 
     return;
 }


@@ -703,7 +827,7 @@ KLDBootstrap::loadKernelComponentKexts(void)
         }
     }
 
         }
     }
 

-    OSSafeRelease(theKext);
+    OSSafeReleaseNULL(theKext);

     return result;
 }
 
     return result;
 }
 


@@ -775,8 +899,8 @@ KLDBootstrap::loadKernelExternalComponents(void)
     }
 
 finish:
     }
 
 finish:

-    OSSafeRelease(keyIterator);
-    OSSafeRelease(extensionsDict);
+    OSSafeReleaseNULL(keyIterator);
+    OSSafeReleaseNULL(extensionsDict);

 
     return;
 }
 
     return;
 }


@@ -895,10 +1019,10 @@ KLDBootstrap::readBuiltinPersonalities(void)
     gIOCatalogue->addDrivers(allPersonalities, false);
 
 finish:
     gIOCatalogue->addDrivers(allPersonalities, false);
 
 finish:

-    OSSafeRelease(parsedXML);
-    OSSafeRelease(allPersonalities);
-    OSSafeRelease(errorString);
-    OSSafeRelease(personalitiesIterator);
+    OSSafeReleaseNULL(parsedXML);
+    OSSafeReleaseNULL(allPersonalities);
+    OSSafeReleaseNULL(errorString);
+    OSSafeReleaseNULL(personalitiesIterator);

     return;
 }
 
     return;
 }