Working on windows.crypto object + API + test

2026-06-08 14:31:45 +00:00 · 2016-12-30 18:03:08 +01:00
parent d5b70d829f
commit 68e809728a
3 changed files with 136 additions and 0 deletions
@@ -0,0 +1,83 @@
+from os import urandom
+
+from windows import winproxy
+from windows.crypto import DEFAULT_ENCODING
+from windows.crypto.helper import ECRYPT_DATA_BLOB
+from windows.generated_def import *
+
+def encode_init_vector(data):
+    blob = ECRYPT_DATA_BLOB.from_string(data)
+    size = DWORD()
+    buf = None
+    winproxy.CryptEncodeObjectEx(DEFAULT_ENCODING, X509_OCTET_STRING, ctypes.byref(blob), 0, None, buf, size)
+    buf = (BYTE * size.value)()
+    winproxy.CryptEncodeObjectEx(DEFAULT_ENCODING, X509_OCTET_STRING, ctypes.byref(blob), 0, None, buf, size)
+    return buf[:]
+
+
+class GenerateInitVector(object):
+    def __repr__(self):
+        return "GenerateInitVector()"
+
+    def generate_init_vector(self, algo):
+        if algo in [szOID_OIWSEC_desCBC, szOID_RSA_DES_EDE3_CBC]:
+            return urandom(8)
+        if algo in [szOID_NIST_AES128_CBC, szOID_NIST_AES192_CBC, szOID_NIST_AES256_CBC]:
+            return urandom(16)
+        return None
+geninitvector = GenerateInitVector()
+
+
+def encrypt(cert, msg, algo=szOID_RSA_DES_EDE3_CBC, initvector=geninitvector):
+    alg_ident = CRYPT_ALGORITHM_IDENTIFIER()
+    alg_ident.pszObjId = algo
+    # Set (compute if needed) the IV
+    if initvector is None:
+        alg_ident.Parameters.cbData = 0
+    elif initvector is geninitvector:
+        initvector = initvector.generate_init_vector(algo)
+        if initvector is None:
+            raise ValueError("I Don't know how to generate an <initvector> for <{0}> please provide one (or None)".format(algo))
+        initvector_encoded = encode_init_vector(initvector)
+        alg_ident.Parameters = ECRYPT_DATA_BLOB.from_string(initvector_encoded)
+    else:
+        initvector_encoded = encode_init_vector(initvector)
+        alg_ident.Parameters = ECRYPT_DATA_BLOB.from_string(initvector_encoded)
+
+    # Setup encryption parameters
+    param = CRYPT_ENCRYPT_MESSAGE_PARA()
+    param.cbSize = ctypes.sizeof(param)
+    param.dwMsgEncodingType = DEFAULT_ENCODING
+    param.hCryptProv = None
+    param.ContentEncryptionAlgorithm = alg_ident
+    param.pvEncryptionAuxInfo = None
+    param.dwFlags = 0
+    param.dwInnerContentType = 0
+
+    certs = (PCERT_CONTEXT * 1)(cert)
+    #Ask the output buffer size
+    size = DWORD()
+    winproxy.CryptEncryptMessage(param, len(certs), certs, msg, len(msg), None, size)
+    #Encrypt the msg
+    buf =  (BYTE * size.value)()
+    winproxy.CryptEncryptMessage(param, len(certs), certs, msg, len(msg), buf, size)
+    return bytearray(buf[:size.value])
+
+
+def decrypt(cert_store, encrypted):
+    # Setup decryption parameters
+    dparam = CRYPT_DECRYPT_MESSAGE_PARA()
+    dparam.cbSize = ctypes.sizeof(dparam)
+    dparam.dwMsgAndCertEncodingType = DEFAULT_ENCODING
+    dparam.cCertStore = 1
+    dparam.rghCertStore = (cert_store,)
+    dparam.dwFlags = 0
+
+    #Ask the output buffer size
+    buf = (BYTE * len(encrypted)).from_buffer_copy(encrypted)
+    dcryptsize = DWORD()
+    winproxy.CryptDecryptMessage(dparam, buf, ctypes.sizeof(buf), None, dcryptsize, None)
+    #Decrypt the msg
+    dcryptbuff = (BYTE * dcryptsize.value)()
+    winproxy.CryptDecryptMessage(dparam, buf, ctypes.sizeof(buf), dcryptbuff, dcryptsize, None)
+    return str(bytearray(dcryptbuff[:dcryptsize.value]))
@@ -0,0 +1,40 @@
+from windows import winproxy
+from windows.generated_def import *
+
+from windows.crypto.helper import ECRYPT_DATA_BLOB
+from windows.crypto import DEFAULT_ENCODING, EHCERTSTORE
+
+
+def generate_selfsigned_certificate(name="CN=Testing", prov=None, key_info=None, flags=0, signature_algo=None):
+    size = ULONG(len(name) + 0x100)
+    buffer = (ctypes.c_ubyte * size.value)()
+    winproxy.CertStrToNameA(X509_ASN_ENCODING, name,  CERT_OID_NAME_STR, None, buffer, size, None)
+    blobname = ECRYPT_DATA_BLOB(size.value, buffer)
+    cert = winproxy.CertCreateSelfSignCertificate(prov, blobname, flags, key_info, signature_algo, None, None, None)
+    return windows.crypto.CertificatContext(cert[0])
+
+
+def generate_key(prov, keytype=AT_KEYEXCHANGE, flags=CRYPT_EXPORTABLE):
+    key = HCRYPTKEY()
+    winproxy.CryptGenKey(prov, keytype, flags , key)
+    return key
+    # print(key[0])
+    # print("[OK] Key created")
+    # size = DWORD()
+    # winproxy.CryptExportKey(key, None, PRIVATEKEYBLOB, 0, None, size)
+    # buffer = (BYTE *  size.value)()
+    # print("needed size = {0}".format(size))
+    # winproxy.CryptExportKey(key, None, PRIVATEKEYBLOB, 0, buffer, size)
+    # print("[OK] Key in buffer")
+    # keyraw = bytearray(buffer)
+    # # openssl.exe rsa -in key.out -inform MS\PRIVATEKEYBLOB -text
+    # save_as(keyraw, "key.out")
+    # #res = ctypes.WinDLL("advapi32").CryptReleaseContext(prov, 0)
+    # return key
+
+def generate_pfx(hstore, password=None):
+    blob = ECRYPT_DATA_BLOB(0, None)
+    winproxy.PFXExportCertStoreEx(hstore, blob, password, None, EXPORT_PRIVATE_KEYS | REPORT_NO_PRIVATE_KEY | REPORT_NOT_ABLE_TO_EXPORT_PRIVATE_KEY)
+    blob.pbData = (ctypes.c_ubyte * blob.cbData)()
+    winproxy.PFXExportCertStoreEx(hstore, blob, password, None, EXPORT_PRIVATE_KEYS | REPORT_NO_PRIVATE_KEY | REPORT_NOT_ABLE_TO_EXPORT_PRIVATE_KEY)
+    return blob.data
@@ -0,0 +1,13 @@
+from windows.generated_def import CRYPT_DATA_BLOB, BYTE
+
+class ECRYPT_DATA_BLOB(CRYPT_DATA_BLOB):
+    @classmethod
+    def from_string(cls, buf):
+        self = cls()
+        self.cbData = len(buf)
+        self.pbData = (BYTE * self.cbData)(*bytearray(buf))
+        return self
+
+    @property
+    def data(self):
+        return bytearray(self.pbData[:self.cbData])