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-rw-r--r--paramiko/_winapi.py274
1 files changed, 274 insertions, 0 deletions
diff --git a/paramiko/_winapi.py b/paramiko/_winapi.py
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+++ b/paramiko/_winapi.py
@@ -0,0 +1,274 @@
+"""
+Windows API functions implemented as ctypes functions and classes as found
+in jaraco.windows (2.10).
+
+If you encounter issues with this module, please consider reporting the issues
+in jaraco.windows and asking the author to port the fixes back here.
+"""
+
+import ctypes
+import ctypes.wintypes
+import __builtin__
+
+try:
+ USHORT = ctypes.wintypes.USHORT
+except AttributeError:
+ USHORT = ctypes.c_ushort
+
+######################
+# jaraco.windows.error
+
+def format_system_message(errno):
+ """
+ Call FormatMessage with a system error number to retrieve
+ the descriptive error message.
+ """
+ # first some flags used by FormatMessageW
+ ALLOCATE_BUFFER = 0x100
+ ARGUMENT_ARRAY = 0x2000
+ FROM_HMODULE = 0x800
+ FROM_STRING = 0x400
+ FROM_SYSTEM = 0x1000
+ IGNORE_INSERTS = 0x200
+
+ # Let FormatMessageW allocate the buffer (we'll free it below)
+ # Also, let it know we want a system error message.
+ flags = ALLOCATE_BUFFER | FROM_SYSTEM
+ source = None
+ message_id = errno
+ language_id = 0
+ result_buffer = ctypes.wintypes.LPWSTR()
+ buffer_size = 0
+ arguments = None
+ bytes = ctypes.windll.kernel32.FormatMessageW(
+ flags,
+ source,
+ message_id,
+ language_id,
+ ctypes.byref(result_buffer),
+ buffer_size,
+ arguments,
+ )
+ # note the following will cause an infinite loop if GetLastError
+ # repeatedly returns an error that cannot be formatted, although
+ # this should not happen.
+ handle_nonzero_success(bytes)
+ message = result_buffer.value
+ ctypes.windll.kernel32.LocalFree(result_buffer)
+ return message
+
+
+class WindowsError(__builtin__.WindowsError):
+ "more info about errors at http://msdn.microsoft.com/en-us/library/ms681381(VS.85).aspx"
+
+ def __init__(self, value=None):
+ if value is None:
+ value = ctypes.windll.kernel32.GetLastError()
+ strerror = format_system_message(value)
+ super(WindowsError, self).__init__(value, strerror)
+
+ @property
+ def message(self):
+ return self.strerror
+
+ @property
+ def code(self):
+ return self.winerror
+
+ def __str__(self):
+ return self.message
+
+ def __repr__(self):
+ return '{self.__class__.__name__}({self.winerror})'.format(**vars())
+
+def handle_nonzero_success(result):
+ if result == 0:
+ raise WindowsError()
+
+
+CreateFileMapping = ctypes.windll.kernel32.CreateFileMappingW
+CreateFileMapping.argtypes = [
+ ctypes.wintypes.HANDLE,
+ ctypes.c_void_p,
+ ctypes.wintypes.DWORD,
+ ctypes.wintypes.DWORD,
+ ctypes.wintypes.DWORD,
+ ctypes.wintypes.LPWSTR,
+]
+CreateFileMapping.restype = ctypes.wintypes.HANDLE
+
+MapViewOfFile = ctypes.windll.kernel32.MapViewOfFile
+MapViewOfFile.restype = ctypes.wintypes.HANDLE
+
+class MemoryMap(object):
+ """
+ A memory map object which can have security attributes overrideden.
+ """
+ def __init__(self, name, length, security_attributes=None):
+ self.name = name
+ self.length = length
+ self.security_attributes = security_attributes
+ self.pos = 0
+
+ def __enter__(self):
+ p_SA = (
+ ctypes.byref(self.security_attributes)
+ if self.security_attributes else None
+ )
+ INVALID_HANDLE_VALUE = -1
+ PAGE_READWRITE = 0x4
+ FILE_MAP_WRITE = 0x2
+ filemap = ctypes.windll.kernel32.CreateFileMappingW(
+ INVALID_HANDLE_VALUE, p_SA, PAGE_READWRITE, 0, self.length,
+ unicode(self.name))
+ handle_nonzero_success(filemap)
+ if filemap == INVALID_HANDLE_VALUE:
+ raise Exception("Failed to create file mapping")
+ self.filemap = filemap
+ self.view = MapViewOfFile(filemap, FILE_MAP_WRITE, 0, 0, 0)
+ return self
+
+ def seek(self, pos):
+ self.pos = pos
+
+ def write(self, msg):
+ n = len(msg)
+ if self.pos + n >= self.length: # A little safety.
+ raise ValueError("Refusing to write %d bytes" % n)
+ ctypes.windll.kernel32.RtlMoveMemory(self.view + self.pos, msg, n)
+ self.pos += n
+
+ def read(self, n):
+ """
+ Read n bytes from mapped view.
+ """
+ out = ctypes.create_string_buffer(n)
+ ctypes.windll.kernel32.RtlMoveMemory(out, self.view + self.pos, n)
+ self.pos += n
+ return out.raw
+
+ def __exit__(self, exc_type, exc_val, tb):
+ ctypes.windll.kernel32.UnmapViewOfFile(self.view)
+ ctypes.windll.kernel32.CloseHandle(self.filemap)
+
+#########################
+# jaraco.windows.security
+
+class TokenInformationClass:
+ TokenUser = 1
+
+class TOKEN_USER(ctypes.Structure):
+ num = 1
+ _fields_ = [
+ ('SID', ctypes.c_void_p),
+ ('ATTRIBUTES', ctypes.wintypes.DWORD),
+ ]
+
+
+class SECURITY_DESCRIPTOR(ctypes.Structure):
+ """
+ typedef struct _SECURITY_DESCRIPTOR
+ {
+ UCHAR Revision;
+ UCHAR Sbz1;
+ SECURITY_DESCRIPTOR_CONTROL Control;
+ PSID Owner;
+ PSID Group;
+ PACL Sacl;
+ PACL Dacl;
+ } SECURITY_DESCRIPTOR;
+ """
+ SECURITY_DESCRIPTOR_CONTROL = USHORT
+ REVISION = 1
+
+ _fields_ = [
+ ('Revision', ctypes.c_ubyte),
+ ('Sbz1', ctypes.c_ubyte),
+ ('Control', SECURITY_DESCRIPTOR_CONTROL),
+ ('Owner', ctypes.c_void_p),
+ ('Group', ctypes.c_void_p),
+ ('Sacl', ctypes.c_void_p),
+ ('Dacl', ctypes.c_void_p),
+ ]
+
+class SECURITY_ATTRIBUTES(ctypes.Structure):
+ """
+ typedef struct _SECURITY_ATTRIBUTES {
+ DWORD nLength;
+ LPVOID lpSecurityDescriptor;
+ BOOL bInheritHandle;
+ } SECURITY_ATTRIBUTES;
+ """
+ _fields_ = [
+ ('nLength', ctypes.wintypes.DWORD),
+ ('lpSecurityDescriptor', ctypes.c_void_p),
+ ('bInheritHandle', ctypes.wintypes.BOOL),
+ ]
+
+ def __init__(self, *args, **kwargs):
+ super(SECURITY_ATTRIBUTES, self).__init__(*args, **kwargs)
+ self.nLength = ctypes.sizeof(SECURITY_ATTRIBUTES)
+
+ def _get_descriptor(self):
+ return self._descriptor
+ def _set_descriptor(self, descriptor):
+ self._descriptor = descriptor
+ self.lpSecurityDescriptor = ctypes.addressof(descriptor)
+ descriptor = property(_get_descriptor, _set_descriptor)
+
+def GetTokenInformation(token, information_class):
+ """
+ Given a token, get the token information for it.
+ """
+ data_size = ctypes.wintypes.DWORD()
+ ctypes.windll.advapi32.GetTokenInformation(token, information_class.num,
+ 0, 0, ctypes.byref(data_size))
+ data = ctypes.create_string_buffer(data_size.value)
+ handle_nonzero_success(ctypes.windll.advapi32.GetTokenInformation(token,
+ information_class.num,
+ ctypes.byref(data), ctypes.sizeof(data),
+ ctypes.byref(data_size)))
+ return ctypes.cast(data, ctypes.POINTER(TOKEN_USER)).contents
+
+class TokenAccess:
+ TOKEN_QUERY = 0x8
+
+def OpenProcessToken(proc_handle, access):
+ result = ctypes.wintypes.HANDLE()
+ proc_handle = ctypes.wintypes.HANDLE(proc_handle)
+ handle_nonzero_success(ctypes.windll.advapi32.OpenProcessToken(
+ proc_handle, access, ctypes.byref(result)))
+ return result
+
+def get_current_user():
+ """
+ Return a TOKEN_USER for the owner of this process.
+ """
+ process = OpenProcessToken(
+ ctypes.windll.kernel32.GetCurrentProcess(),
+ TokenAccess.TOKEN_QUERY,
+ )
+ return GetTokenInformation(process, TOKEN_USER)
+
+def get_security_attributes_for_user(user=None):
+ """
+ Return a SECURITY_ATTRIBUTES structure with the SID set to the
+ specified user (uses current user if none is specified).
+ """
+ if user is None:
+ user = get_current_user()
+
+ assert isinstance(user, TOKEN_USER), "user must be TOKEN_USER instance"
+
+ SD = SECURITY_DESCRIPTOR()
+ SA = SECURITY_ATTRIBUTES()
+ # by attaching the actual security descriptor, it will be garbage-
+ # collected with the security attributes
+ SA.descriptor = SD
+ SA.bInheritHandle = 1
+
+ ctypes.windll.advapi32.InitializeSecurityDescriptor(ctypes.byref(SD),
+ SECURITY_DESCRIPTOR.REVISION)
+ ctypes.windll.advapi32.SetSecurityDescriptorOwner(ctypes.byref(SD),
+ user.SID, 0)
+ return SA