/*
* Testing whether the current process is getting the focus.
*
* See frameworks/base/core/java/android/view/IWindow.aidl and
* frameworks/base/services/java/com/android/server/WindowManagerService.java
* for more details.
*/
private static bool GainingWindowFocus(Thread current, binder_transaction_data tr)
{
const int OP_windowFocusChanged = 5;
if (tr.code != OP_windowFocusChanged || tr.data_size != 0x3c)
{
return(false);
}
var buf = InspectionBuffer;
tr.data_buffer.Read(current, buf);
bool header_matched = true;
for (var i = 0; i < WindowFocusChangedHeader.Length && header_matched; ++i)
{
if (buf[i] != WindowFocusChangedHeader[i])
{
header_matched = false;
}
}
if (!header_matched)
{
return(false);
}
int get_focus;
(tr.data_buffer + WindowFocusChangedHeader.Length).Read(current, out get_focus);
return(get_focus == 1);
}
/*
* Heuristic for determing whether a transaction is mapping the screen buffer
* into the process.
*
* See frameworks/base/libs/ui/GraphicBuffer.cpp for more details.
*/
private static bool IsScreenSharingTransaction(Thread current, ref binder_transaction_data tr)
{
int a0, a1, a2;
const uint SystemEuid = 1000;
if (tr.sender_euid != SystemEuid || tr.data_size != 0x54 || tr.offsets_size != 4)
{
return(false);
}
tr.data_buffer.Read(current, out a0);
(tr.data_buffer + sizeof(int)).Read(current, out a1);
(tr.data_buffer + sizeof(int) * 2).Read(current, out a2);
return(a0 == 0x3c && a1 == 0x1 && a2 == 0x47424652);
}
/*
* Testing whether the current process is getting the focus.
*
* See frameworks/base/core/java/android/view/IWindow.aidl and
* frameworks/base/services/java/com/android/server/WindowManagerService.java
* for more details.
*/
private static bool GainingWindowFocus(Thread current, binder_transaction_data tr)
{
const int OP_windowFocusChanged = 5;
if (tr.code != OP_windowFocusChanged || tr.data_size != 0x3c)
return false;
var buf = InspectionBuffer;
tr.data_buffer.Read(current, buf, buf.Length);
bool header_matched = true;
for (var i = 0; i < WindowFocusChangedHeader.Length && header_matched; ++i)
{
if (buf[i] != WindowFocusChangedHeader[i])
header_matched = false;
}
if (!header_matched)
return false;
int get_focus;
(tr.data_buffer + WindowFocusChangedHeader.Length).Read(current, out get_focus);
return get_focus == 1;
}
private static int PatchReadTransaction(Thread current, Pointer marshaledBufferStart, ref binder_transaction_data tr)
{
if (tr.data_size != 0)
tr.data_buffer += current.Parent.binderVMStart.Value.ToUInt32();
if (tr.offsets_size != 0)
tr.data_offsets += current.Parent.binderVMStart.Value.ToUInt32();
if (GainingWindowFocus(current, tr))
Globals.SecurityManager.OnActiveProcessChanged(current.Parent);
for (var off_ptr = tr.data_offsets; off_ptr < tr.data_offsets + tr.offsets_size; off_ptr += 4)
{
var fp = new flat_binder_object();
int off;
if (off_ptr.Read(current, out off) != 0)
{
Arch.Console.Write("Can't get offset");
return -1;
}
var fp_ptr = tr.data_buffer + off;
if (fp_ptr.Read(current, out fp) != 0)
{
Arch.Console.Write("Read fp failed, ptr:");
Arch.Console.Write(fp_ptr.Value.ToInt32());
Arch.Console.WriteLine();
return -1;
}
//Arch.Console.Write("off_ptr:");
//Arch.Console.Write(tr->data_offsets.Value.ToUInt32());
//Arch.Console.Write(" Off end:");
//Arch.Console.Write((tr->data_offsets + tr->offsets_size).Value.ToUInt32());
//Arch.Console.WriteLine();
switch (fp.type)
{
case BinderINode.BINDER_TYPE_FD:
{
var proc = current.Parent;
var linux_fd = fp.binderOrHandle.Value.ToInt32();
GenericINode inode;
if (IsScreenSharingTransaction(current, ref tr))
inode = new ScreenBufferINode(linux_fd, proc.helperPid);
else
inode = new BinderSharedINode(linux_fd, proc.helperPid);
int fd = proc.GetUnusedFd();
proc.InstallFd(fd, new File(proc, inode, FileSystem.O_RDWR, 0));
// Patch the data structure
(fp_ptr + flat_binder_object.OFFSET_OF_HANDLE).Write(current, fd);
}
break;
case BinderINode.BINDER_TYPE_HANDLE:
// sliently ignore it (it seems safe)
break;
default:
Arch.Console.Write("BinderINode::PatchReadTransaction ignoring ");
Arch.Console.Write(fp.type);
Arch.Console.WriteLine();
break;
}
}
return 0;
}
/*
* Heuristic for determing whether a transaction is mapping the screen buffer
* into the process.
*
* See frameworks/base/libs/ui/GraphicBuffer.cpp for more details.
*/
private static bool IsScreenSharingTransaction(Thread current, ref binder_transaction_data tr)
{
int a0, a1, a2;
const uint SystemEuid = 1000;
if (tr.sender_euid != SystemEuid || tr.data_size != 0x54 || tr.offsets_size != 4)
return false;
tr.data_buffer.Read(current, out a0);
(tr.data_buffer + sizeof(int)).Read(current, out a1);
(tr.data_buffer + sizeof(int) * 2).Read(current, out a2);
return a0 == 0x3c && a1 == 0x1 && a2 == 0x47424652;
}
private static int PatchReadTransaction(Thread current, Pointer marshaledBufferStart, ref binder_transaction_data tr)
{
Contract.Requires(current.Parent != null);
if (tr.data_size != 0)
{
tr.data_buffer += current.Parent.binderVMStart.Value.ToUInt32();
}
if (tr.offsets_size != 0)
{
tr.data_offsets += current.Parent.binderVMStart.Value.ToUInt32();
}
if (GainingWindowFocus(current, tr))
{
Globals.SecurityManager.OnActiveProcessChanged(current.Parent);
}
for (var off_ptr = tr.data_offsets; off_ptr < tr.data_offsets + tr.offsets_size; off_ptr += 4)
{
var fp = new flat_binder_object();
int off;
if (off_ptr.Read(current, out off) != 0)
{
Arch.Console.Write("Can't get offset");
return(-1);
}
var fp_ptr = tr.data_buffer + off;
if (fp_ptr.Read(current, out fp) != 0)
{
Arch.Console.Write("Read fp failed, ptr:");
Arch.Console.Write(fp_ptr.Value.ToInt32());
Arch.Console.WriteLine();
return(-1);
}
//Arch.Console.Write("off_ptr:");
//Arch.Console.Write(tr->data_offsets.Value.ToUInt32());
//Arch.Console.Write(" Off end:");
//Arch.Console.Write((tr->data_offsets + tr->offsets_size).Value.ToUInt32());
//Arch.Console.WriteLine();
switch (fp.type)
{
case BinderINode.BINDER_TYPE_FD:
{
var proc = current.Parent;
var linux_fd = fp.binderOrHandle.Value.ToInt32();
GenericINode inode;
if (IsScreenSharingTransaction(current, ref tr))
{
inode = new ScreenBufferINode(linux_fd, proc.helperPid);
}
else
{
inode = new BinderSharedINode(linux_fd, proc.helperPid);
}
int fd = proc.GetUnusedFd();
proc.InstallFd(fd, new File(proc, inode, FileSystem.O_RDWR, 0));
// Patch the data structure
(fp_ptr + flat_binder_object.OFFSET_OF_HANDLE).Write(current, fd);
}
break;
case BinderINode.BINDER_TYPE_HANDLE:
// sliently ignore it (it seems safe)
break;
default:
Arch.Console.Write("BinderINode::PatchReadTransaction ignoring ");
Arch.Console.Write(fp.type);
Arch.Console.WriteLine();
break;
}
}
return(0);
}
