from ctypes import Structure, POINTER, c_void_p, cast, create_string_buffer, \
c_char_p, byref, memmove
from ctypes import windll, WinDLL, WINFUNCTYPE
try:
from ctypes import wintypes
except ValueError:
# see http://bugs.python.org/issue16396
raise ImportError("wintypes")
from keyring.util.escape import u
# Crypto API ctypes bindings
class DATA_BLOB(Structure):
_fields_ = [('cbData', wintypes.DWORD),
('pbData', POINTER(wintypes.BYTE))]
class CRYPTPROTECT_PROMPTSTRUCT(Structure):
_fields_ = [('cbSize', wintypes.DWORD),
('dwPromptFlags', wintypes.DWORD),
('hwndApp', wintypes.HWND),
('szPrompt', POINTER(wintypes.WCHAR))]
# Flags for CRYPTPROTECT_PROMPTSTRUCT
CRYPTPROTECT_PROMPT_ON_UNPROTECT = 1
CRYPTPROTECT_PROMPT_ON_PROTECT = 2
# Flags for CryptProtectData/CryptUnprotectData
CRYPTPROTECT_UI_FORBIDDEN = 0x01
CRYPTPROTECT_LOCAL_MACHINE = 0x04
CRYPTPROTECT_CRED_SYNC = 0x08
CRYPTPROTECT_AUDIT = 0x10
CRYPTPROTECT_NO_RECOVERY = 0x20
CRYPTPROTECT_VERIFY_PROTECTION = 0x40
CRYPTPROTECT_CRED_REGENERATE = 0x80
# Crypto API Functions
_dll = WinDLL('CRYPT32.DLL')
CryptProtectData = WINFUNCTYPE(wintypes.BOOL,
POINTER(DATA_BLOB),
POINTER(wintypes.WCHAR),
POINTER(DATA_BLOB),
c_void_p,
POINTER(CRYPTPROTECT_PROMPTSTRUCT),
wintypes.DWORD,
POINTER(DATA_BLOB))(('CryptProtectData', _dll))
CryptUnprotectData = WINFUNCTYPE(wintypes.BOOL,
POINTER(DATA_BLOB),
POINTER(wintypes.WCHAR),
POINTER(DATA_BLOB),
c_void_p,
POINTER(CRYPTPROTECT_PROMPTSTRUCT),
wintypes.DWORD, POINTER(DATA_BLOB))(
('CryptUnprotectData', _dll))
# Functions
def encrypt(data, non_interactive=0):
blobin = DATA_BLOB(cbData=len(data),
pbData=cast(c_char_p(data),
POINTER(wintypes.BYTE)))
blobout = DATA_BLOB()
if not CryptProtectData(byref(blobin),
u('python-keyring-lib.win32crypto'),
None, None, None,
CRYPTPROTECT_UI_FORBIDDEN,
byref(blobout)):
raise OSError("Can't encrypt")
encrypted = create_string_buffer(blobout.cbData)
memmove(encrypted, blobout.pbData, blobout.cbData)
windll.kernel32.LocalFree(blobout.pbData)
return encrypted.raw
def decrypt(encrypted, non_interactive=0):
blobin = DATA_BLOB(cbData=len(encrypted),
pbData=cast(c_char_p(encrypted),
POINTER(wintypes.BYTE)))
blobout = DATA_BLOB()
if not CryptUnprotectData(byref(blobin),
u('python-keyring-lib.win32crypto'),
None, None, None,
CRYPTPROTECT_UI_FORBIDDEN,
byref(blobout)):
raise OSError("Can't decrypt")
data = create_string_buffer(blobout.cbData)
memmove(data, blobout.pbData, blobout.cbData)
windll.kernel32.LocalFree(blobout.pbData)
return data.raw