testing/kernel-cache-tests/kext-vtable-patching-overrides/test.py

   1 #!/usr/bin/python2.7
   2
   3 import os
   4 import KernelCollection
   5
   6 # This verifies that a kext can bind to another kext
   7 # foo.kext exports foo and bar.kext uses it
   8 # This is the same as kext-vtable-patching but checks that overrides of methods in parent classes
   9 # are propagated to child classes
  10 # Foo defines fooOverride().
  11
  12 def check(kernel_cache):
  13     kernel_cache.buildKernelCollection("x86_64", "/kext-vtable-patching-overrides/main.kc", "/kext-vtable-patching-overrides/main.kernel", "/kext-vtable-patching-overrides/extensions", ["com.apple.foo", "com.apple.bar"], [])
  14     kernel_cache.analyze("/kext-vtable-patching-overrides/main.kc", ["-layout", "-arch", "x86_64"])
  15
  16     assert len(kernel_cache.dictionary()["dylibs"]) == 3
  17     assert kernel_cache.dictionary()["dylibs"][0]["name"] == "com.apple.kernel"
  18     assert kernel_cache.dictionary()["dylibs"][1]["name"] == "com.apple.bar"
  19     assert kernel_cache.dictionary()["dylibs"][2]["name"] == "com.apple.foo"
  20
  21     # Get the addresses for the symbols we are looking at.  This will make it easier to work out the fixup slots
  22     kernel_cache.analyze("/kext-vtable-patching-overrides/main.kc", ["-symbols", "-arch", "x86_64"])
  23
  24     # From bar, find the vtable and its override of foo()
  25     # Bar::foo()
  26     assert kernel_cache.dictionary()["dylibs"][1]["global-symbols"][3]["name"] == "__ZN3Bar3fooEv"
  27     assert kernel_cache.dictionary()["dylibs"][1]["global-symbols"][3]["vmAddr"] == "0x24F10"
  28
  29     # From foo, we want to know where the vtable is, and the foo() and fooUsed0() slots in that vtable
  30     # Foo::fooOverride()
  31     assert kernel_cache.dictionary()["dylibs"][2]["global-symbols"][3]["name"] == "__ZN3Foo11fooOverrideEv"
  32     assert kernel_cache.dictionary()["dylibs"][2]["global-symbols"][3]["vmAddr"] == "0x26BA0"
  33     # Foo::foo()
  34     assert kernel_cache.dictionary()["dylibs"][2]["global-symbols"][7]["name"] == "__ZN3Foo3fooEv"
  35     assert kernel_cache.dictionary()["dylibs"][2]["global-symbols"][7]["vmAddr"] == "0x26B80"
  36     # Foo::fooUsed0()
  37     assert kernel_cache.dictionary()["dylibs"][2]["global-symbols"][8]["name"] == "__ZN3Foo8fooUsed0Ev"
  38     assert kernel_cache.dictionary()["dylibs"][2]["global-symbols"][8]["vmAddr"] == "0x26BC0"
  39
  40     # From foo
  41     # FooSub::fooOverride()
  42     assert kernel_cache.dictionary()["dylibs"][2]["global-symbols"][21]["name"] == "__ZN6FooSub11fooOverrideEv"
  43     assert kernel_cache.dictionary()["dylibs"][2]["global-symbols"][21]["vmAddr"] == "0x26EA0"
  44     # Foo::foo()
  45     assert kernel_cache.dictionary()["dylibs"][2]["global-symbols"][22]["name"] == "__ZN6FooSub3fooEv"
  46     assert kernel_cache.dictionary()["dylibs"][2]["global-symbols"][22]["vmAddr"] == "0x26E80"
  47
  48
  49     # Check the fixups
  50     kernel_cache.analyze("/kext-vtable-patching-overrides/main.kc", ["-fixups", "-arch", "x86_64"])
  51
  52     # In vtable for Foo, we match the entry for Foo::foo() by looking for its value on the RHS of the fixup
  53     assert kernel_cache.dictionary()["fixups"]["0x23150"] == "kc(0) + 0x26B80"
  54     # Then the following fixup should be to Foo::fooOverride()
  55     assert kernel_cache.dictionary()["fixups"]["0x23158"] == "kc(0) + 0x26BA0"
  56     # Then the following fixup should be to Foo::fooUsed0()
  57     assert kernel_cache.dictionary()["fixups"]["0x23160"] == "kc(0) + 0x26BC0"
  58
  59     # In vtable for FooSub, we match the entry for FooSub::foo() by looking for its value on the RHS of the fixup
  60     assert kernel_cache.dictionary()["fixups"]["0x233A8"] == "kc(0) + 0x26E80"
  61     # Then the following fixup should be to FooSub::fooOverride()
  62     assert kernel_cache.dictionary()["fixups"]["0x233B0"] == "kc(0) + 0x26EA0"
  63     # Then the following fixup should be to Foo::fooUsed0()
  64     assert kernel_cache.dictionary()["fixups"]["0x233B8"] == "kc(0) + 0x26BC0"
  65
  66     # Now in bar, again match the entry for its Bar::foo() symbol
  67     assert kernel_cache.dictionary()["fixups"]["0x21150"] == "kc(0) + 0x24F10"
  68     # Then the following fixup should be to FooSub::fooOverride()
  69     assert kernel_cache.dictionary()["fixups"]["0x21158"] == "kc(0) + 0x26EA0"
  70     # And if the patching was correct, then following entry should be to Foo::fooUsed0()
  71     assert kernel_cache.dictionary()["fixups"]["0x21160"] == "kc(0) + 0x26BC0"
  72
  73
  74 # [~]> xcrun -sdk macosx.internal cc -arch x86_64 -Wl,-static -mkernel -nostdlib -Wl,-e,__start -Wl,-pie main.cpp -Wl,-pagezero_size,0x0 -o main.kernel -Wl,-image_base,0x10000 -Wl,-segaddr,__HIB,0x4000 -Wl,-add_split_seg_info -Wl,-install_name,/usr/lib/swift/split.seg.v2.hack -iwithsysroot /System/Library/Frameworks/Kernel.framework/Headers -Wl,-sectcreate,__LINKINFO,__symbolsets,SymbolSets.plist -Wl,-segprot,__LINKINFO,r--,r--
  75 # [~]> xcrun -sdk macosx.internal cc -arch x86_64 -Wl,-kext -mkernel -nostdlib -Wl,-no_data_const foo.cpp -o extensions/foo.kext/foo -iwithsysroot /System/Library/Frameworks/Kernel.framework/Headers -DFOO_USED=1 -DFOO_OVERRIDE=1
  76 # [~]> xcrun -sdk macosx.internal cc -arch x86_64 -Wl,-kext -mkernel -nostdlib -Wl,-no_data_const bar.cpp -o extensions/bar.kext/bar -iwithsysroot /System/Library/Frameworks/Kernel.framework/Headers
  77 # [~]> rm -r extensions/*.kext/*.ld
  78