Sandbox: Some cleanup after the previous changes.

No real code change.

BUG=27218
TEST=current tests.

Review URL: http://codereview.chromium.org/597050

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@38837 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 88 insertions, 0 deletions

diff --git a/sandbox/src/resolver_32.cc b/sandbox/src/resolver_32.cc
new file mode 100644
index 0000000..ae5c168
--- /dev/null
+++ b/sandbox/src/resolver_32.cc
@@ -0,0 +1,88 @@
+// Copyright (c) 2006-2010 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "sandbox/src/resolver.h"
+
+#include "sandbox/src/sandbox_nt_util.h"
+
+namespace {
+
+#pragma pack(push, 1)
+struct InternalThunk {
+  // This struct contains roughly the following code:
+  // sub esp, 8                             // Create working space
+  // push edx                               // Save register
+  // mov edx, [esp + 0xc]                   // Get return adddress
+  // mov [esp + 8], edx                     // Store return address
+  // mov dword ptr [esp + 0xc], 0x7c401200  // Store extra argument
+  // mov dword ptr [esp + 4], 0x40010203    // Store address to jump to
+  // pop edx                                // Restore register
+  // ret                                    // Jump to interceptor
+  //
+  // This code only modifies esp and eip so it must work with to normal calling
+  // convention. It is assembled as:
+  //
+  // 00 83ec08           sub     esp,8
+  // 03 52               push    edx
+  // 04 8b54240c         mov     edx,dword ptr [esp + 0Ch]
+  // 08 89542408         mov     dword ptr [esp + 8], edx
+  // 0c c744240c0012407c mov     dword ptr [esp + 0Ch], 7C401200h
+  // 14 c744240403020140 mov     dword ptr [esp + 4], 40010203h
+  // 1c 5a               pop     edx
+  // 1d c3               ret
+  InternalThunk() {
+    opcodes_1 = 0x5208ec83;
+    opcodes_2 = 0x0c24548b;
+    opcodes_3 = 0x08245489;
+    opcodes_4 = 0x0c2444c7;
+    opcodes_5 = 0x042444c7;
+    opcodes_6 = 0xc35a;
+    extra_argument = 0;
+    interceptor_function = 0;
+  };
+  ULONG opcodes_1;         // = 0x5208ec83
+  ULONG opcodes_2;         // = 0x0c24548b
+  ULONG opcodes_3;         // = 0x08245489
+  ULONG opcodes_4;         // = 0x0c2444c7
+  ULONG extra_argument;
+  ULONG opcodes_5;         // = 0x042444c7
+  ULONG interceptor_function;
+  USHORT opcodes_6;         // = 0xc35a
+};
+#pragma pack(pop)
+
+};  // namespace
+
+namespace sandbox {
+
+bool ResolverThunk::SetInternalThunk(void* storage, size_t storage_bytes,
+                                     const void* original_function,
+                                     const void* interceptor) {
+  if (storage_bytes < sizeof(InternalThunk))
+    return false;
+
+  InternalThunk* thunk = new(storage, NT_PLACE) InternalThunk;
+
+#pragma warning(push)
+#pragma warning(disable: 4311)
+  // These casts generate warnings because they are 32 bit specific.
+  thunk->interceptor_function = reinterpret_cast<ULONG>(interceptor);
+  thunk->extra_argument = reinterpret_cast<ULONG>(original_function);
+#pragma warning(pop)
+
+  return true;
+}
+
+size_t ResolverThunk::GetInternalThunkSize() const {
+  return sizeof(InternalThunk);
+}
+
+NTSTATUS ResolverThunk::ResolveTarget(const void* module,
+                                      const char* function_name,
+                                      void** address) {
+  const void** casted = const_cast<const void**>(address);
+  return ResolverThunk::ResolveInterceptor(module, function_name, casted);
+}
+
+}  // namespace sandbox