diff --git a/README.md b/README.md
index ac8dbec..1f2910b 100644
--- a/README.md
+++ b/README.md
@@ -1,6 +1,51 @@
 wincrypto
 =========
 
-Windows Crypto API compatible decryption/encryption for python
+Windows Crypto API compatible decryption/encryption for python. The targeted crypto provider is PROV_RSA_AES.
+
+Implemented algorithms:
+
+ - CALG_RC4
+ - CALG_AES128 
+ - CALG_AES192
+ - CALG_AES256
+ - CALG_RSA_KEYX
+ - CALG_MD5
+ - CALG_SHA1
+ 
+Implemented functions:
+
+ - CryptImportKey
+ - CryptExportKey
+ - CryptEncrypt
+ - CryptDecrypt
+ - CryptGetKeyParam (incomplete)
+ - CryptCreateHash
+ - CryptHashData
+ - CryptGetHashParam
+ - CryptDeriveKey
+  
+An example of how to use this package:
+  
+```python  
+from wincrypto import CryptCreateHash, CryptHashData, CryptDeriveKey, CryptEncrypt, CryptImportKey, CryptExportKey
+from wincrypto.constants import CALG_SHA1, CALG_AES_256, bType_SIMPLEBLOB
+            
+#derive key from password
+sha1_hasher = CryptCreateHash(CALG_SHA1)
+CryptHashData(sha1_hasher, 'Password')
+aes_key = CryptDeriveKey(sha1_hasher, CALG_AES_256)
+
+#encrypt data using key
+encrypted_data = CryptEncrypt(aes_key, 'secret data')
+
+#Import a PUBLICKEYBLOB and export the AES key as SIMPLEBLOB
+TEST_RSA_PUBLIC_MSKEYBLOB = '0602000000a40000525341310004000001000100d1537575000617a37093cec958e8adedd347b5812f' \
+                            '702595fc02fbb870f6a17a26780f9147a6cd938dffff842a1427f8200621f822caaf9b338b4bb3dbda' \
+                            'ce58eedfc7b29b91a1f5ce628657f30f3feb9d909a1a00bd484f628f2db38087eec2f6bb4df1df024b' \
+                            '19af1c97d316c86073c972059d65bc2b47f97e5462a2e8029a'.decode('hex')              
+rsa_pub_key = CryptImportKey(TEST_RSA_PUBLIC_MSKEYBLOB)
+encrypted_aes_key = CryptExportKey(aes_key, rsa_pub_key, bType_SIMPLEBLOB)
+```
 
 [![Build Status](https://travis-ci.org/crappycrypto/wincrypto.png)](https://travis-ci.org/crappycrypto/wincrypto)
\ No newline at end of file
diff --git a/setup.py b/setup.py
index 58e0876..a56a021 100644
--- a/setup.py
+++ b/setup.py
@@ -2,7 +2,7 @@
 
 
 setup(name='wincrypto',
-      version='0.1a',
+      version='0.2a',
       description='Windows Crypto API compatible decryption/encryption',
       url='http://github.com/crappycrypto/wincrypto',
       author='crappycrypto',
diff --git a/tests/algorithms.py b/tests/algorithms.py
index 6c00c68..d3641f0 100644
--- a/tests/algorithms.py
+++ b/tests/algorithms.py
@@ -4,7 +4,7 @@
 from wincrypto.algorithms import symmetric_algorithms, hash_algorithms
 from wincrypto.api import CryptImportKey, CryptExportKey, CryptCreateHash, CryptDeriveKey, \
     CryptHashData
-from wincrypto.definitions import bType_PLAINTEXTKEYBLOB, CALG_MD5, CALG_RC4, CALG_SHA1, CALG_AES_192
+from wincrypto.constants import bType_PLAINTEXTKEYBLOB, CALG_MD5, CALG_RC4, CALG_SHA1, CALG_AES_192, bType_SIMPLEBLOB
 
 
 TEST_RSA_PRIVATE_PEM = '''-----BEGIN RSA PRIVATE KEY-----
@@ -45,7 +45,7 @@ def test_export_import_simple(self):
         rsa_key = wincrypto.algorithms.RSA_KEYX.from_pem(TEST_RSA_PRIVATE_PEM)
         for algorithm in symmetric_algorithms:
             instance = algorithm('A' * algorithm.key_len)
-            blob = CryptExportKey(instance, rsa_key, bType_PLAINTEXTKEYBLOB)
+            blob = CryptExportKey(instance, rsa_key, bType_SIMPLEBLOB)
             instance2 = CryptImportKey(blob, rsa_key)
             self.assertEqual(instance.key, instance2.key)
 
diff --git a/tests/native.py b/tests/native.py
index 5e55eea..cabb5d8 100644
--- a/tests/native.py
+++ b/tests/native.py
@@ -2,11 +2,11 @@
 
 if platform.system() == 'Windows':
     import unittest
-    from wincrypto import native, definitions, api
+    from wincrypto import native, constants, api
     import wincrypto
     from wincrypto.algorithms import symmetric_algorithms, hash_algorithms
     import wincrypto.api
-    from wincrypto.definitions import bType_PLAINTEXTKEYBLOB, bType_SIMPLEBLOB, bType_PRIVATEKEYBLOB, KP_ALGID, \
+    from wincrypto.constants import bType_PLAINTEXTKEYBLOB, bType_SIMPLEBLOB, bType_PRIVATEKEYBLOB, KP_ALGID, \
         KP_KEYLEN, HP_HASHSIZE, HP_ALGID
 
 
@@ -33,7 +33,10 @@
     WMnOk3CjFwYAdXVT0QIDAQAB
     -----END PUBLIC KEY-----'''
 
-    TEST_RSA_PUBLIC_MSKEYBLOB = '\x06\x02\x00\x00\x00\xa4\x00\x00RSA1\x00\x04\x00\x00\x01\x00\x01\x00\xd1Suu\x00\x06\x17\xa3p\x93\xce\xc9X\xe8\xad\xed\xd3G\xb5\x81/p%\x95\xfc\x02\xfb\xb8p\xf6\xa1z&x\x0f\x91G\xa6\xcd\x93\x8d\xff\xff\x84*\x14\'\xf8 \x06!\xf8"\xca\xaf\x9b3\x8bK\xb3\xdb\xda\xceX\xee\xdf\xc7\xb2\x9b\x91\xa1\xf5\xceb\x86W\xf3\x0f?\xeb\x9d\x90\x9a\x1a\x00\xbdHOb\x8f-\xb3\x80\x87\xee\xc2\xf6\xbbM\xf1\xdf\x02K\x19\xaf\x1c\x97\xd3\x16\xc8`s\xc9r\x05\x9de\xbc+G\xf9~Tb\xa2\xe8\x02\x9a'
+    TEST_RSA_PUBLIC_MSKEYBLOB = '0602000000a40000525341310004000001000100d1537575000617a37093cec958e8adedd347b5812f' \
+                                '702595fc02fbb870f6a17a26780f9147a6cd938dffff842a1427f8200621f822caaf9b338b4bb3dbda' \
+                                'ce58eedfc7b29b91a1f5ce628657f30f3feb9d909a1a00bd484f628f2db38087eec2f6bb4df1df024b' \
+                                '19af1c97d316c86073c972059d65bc2b47f97e5462a2e8029a'.decode('hex')
     TEST_RSA_PRIVATE_MSKEYBLOB = '\x07\x02\x00\x00\x00\xa4\x00\x00RSA2\x00\x04\x00\x00\x01\x00\x01\x00\xd1Suu\x00\x06\x17\xa3p\x93\xce\xc9X\xe8\xad\xed\xd3G\xb5\x81/p%\x95\xfc\x02\xfb\xb8p\xf6\xa1z&x\x0f\x91G\xa6\xcd\x93\x8d\xff\xff\x84*\x14\'\xf8 \x06!\xf8"\xca\xaf\x9b3\x8bK\xb3\xdb\xda\xceX\xee\xdf\xc7\xb2\x9b\x91\xa1\xf5\xceb\x86W\xf3\x0f?\xeb\x9d\x90\x9a\x1a\x00\xbdHOb\x8f-\xb3\x80\x87\xee\xc2\xf6\xbbM\xf1\xdf\x02K\x19\xaf\x1c\x97\xd3\x16\xc8`s\xc9r\x05\x9de\xbc+G\xf9~Tb\xa2\xe8\x02\x9a\x9b\\tcH\x8aa\x01\xac\x9b\x12\x11\x8f\xc6i\x8bb\xf6XoJ{\xf9uW\x15\xcc[\x01P\xdd\x86\xd9L\xbb\xa2\x13\xc3{\xa0\xf5\xe1K\x86:\xa01h\xf4\x1a\x89\xbd?\xd4J\xc2\xc5\x9f\x9by\x9a\xb6J\xb5\x03\x9a\xd9$1U\xff\x069\x0e\x1c\xf2\xf3\xcf\x8b;\xd6\x9e%\xca\xcd\xa5\xa5\xd6\x96\xc3)E\xba\x0b\xbe\xeb9\xa2\xb4*\xffw\xb8\xf3\xc9%\x0f}\xcc\xfb\x13\x83WL\xf8\x9fh\x10_D\xde\xf2w\xe3LAz\xd9\xebc?\xc9\xf64\xbb\xea\xa4\xc2@\xfd\xf2\x1b\x04J\r\xaa\x13\x93%\x1cxD\xd6\xdc\xddl\xbb\xb1An^\x83\xe3\xdf\x15\x9f\xa9\x11\x98e-\xd1\x8f\x1c\x8fIBB\xbd\x89\x91<\xba\x12^\x85\x8a\xb3]\xcfh\xae\r~\x07lcD3\x9a9\xe7\xb5\'\xe0e1\xb6\x1c\x93\xe1\xc4+\xf4\xe51b\xf8\xed\x15\xf7h\xaa\x00\xc0]\x17^\xbd\x13\x8d\x0f\xc3\xf7E\xa6\xb8\x83\xe4`\x04\n\x80O\x90A\xe8N{~\x88\xc8\xac\xaf\x03`\x0b\x00\xff\\A\x16\xba\x86|n\x89a\xa4P\x0e\x042\xd5\xe8\xa5\xa6\x9a\x15}?Q\x08\x8e\x83I\x89\x97\xa2n\xb8X\xf4\x16D>q\x1d\xac;\x05\x8c\xc3\x8c\x18\x842\xa2]}h3D\xb8c\xf3\x14\x9aE\x949\x87\xbf\xf1P\xef\x81\xf5=\x80\xdb\xdd\x7f\xe8\xfb2J\xa7\xbc\x8a\xd6PK\x184\x07\xfd\xc0\x93\xaf\rW\xd7\x0c\xcc\x15\x7f\x19*\xd0}\x82\xdai\xaf\xa88\x86N\xbe\xaew\xa1\x97\x1coI\x16\xd4\xfb\xf1R\xce\xa8\x8eUX\xbd\x1f\x93:\x9b*\xa3p(\xdf\xc6u\xd5Rip\xa0\xfe\xd8\xebCsV:p\xc7\t\t\x06\x82i\x14\xa5\xda\xa5#-\xd5\xbb\x08(kW\xd3\xf2xM\xfa\xb7\xdf[\x1a\x1aR\xfc7\xa0\xd6\x990B'
 
     TEST_DATA = str(bytearray(range(64)))  # 64 is a multiple of most blocksizes
@@ -62,7 +65,7 @@ def test_native_simplekeyblob(self):
             rsa_hkey = native.CryptImportKey(self.hprov, rsa_blob)
             for algorithm in symmetric_algorithms:
                 instance = algorithm('A' * algorithm.key_len)
-                blob = wincrypto.api.CryptExportKey(instance, rsa_key.key, bType_SIMPLEBLOB)
+                blob = wincrypto.api.CryptExportKey(instance, rsa_key, bType_SIMPLEBLOB)
                 hkey = native.CryptImportKey(self.hprov, blob, rsa_hkey)
                 c = native.CryptEncrypt(hkey, TEST_DATA)
                 p = instance.decrypt(c)
@@ -118,14 +121,14 @@ def test_hash_native_python(self):
             for algorithm in hash_algorithms:
                 hCryptHash = native.CryptCreateHash(self.hprov, algorithm.alg_id)
                 native.CryptHashData(hCryptHash, TEST_DATA)
-                native_hash_val = native.CryptGetHashParam(hCryptHash, definitions.HP_HASHVAL)
+                native_hash_val = native.CryptGetHashParam(hCryptHash, constants.HP_HASHVAL)
                 native_hash_size = native.CryptGetHashParam(hCryptHash, HP_HASHSIZE)
                 native_hash_algid = native.CryptGetHashParam(hCryptHash, HP_ALGID)
                 native.CryptDestroyHash(hCryptHash)
 
                 md5_hash = wincrypto.api.CryptCreateHash(algorithm.alg_id)
                 wincrypto.api.CryptHashData(md5_hash, TEST_DATA)
-                python_hash = wincrypto.api.CryptGetHashParam(md5_hash, definitions.HP_HASHVAL)
+                python_hash = wincrypto.api.CryptGetHashParam(md5_hash, constants.HP_HASHVAL)
                 python_hash_size = wincrypto.api.CryptGetHashParam(md5_hash, HP_HASHSIZE)
                 python_hash_algid = wincrypto.api.CryptGetHashParam(md5_hash, HP_ALGID)
 
diff --git a/wincrypto/algorithms.py b/wincrypto/algorithms.py
index 79a46fe..038ef70 100644
--- a/wincrypto/algorithms.py
+++ b/wincrypto/algorithms.py
@@ -8,10 +8,11 @@
 from Crypto.PublicKey import RSA
 from Crypto.Util.number import long_to_bytes, bytes_to_long, inverse
 
-from wincrypto.definitions import RSAPUBKEY, RSAPUBKEY_s, RSAPUBKEY_MAGIC, PUBLICKEYSTRUC_s, bType_PUBLICKEYBLOB, \
+from wincrypto.constants import RSAPUBKEY, RSAPUBKEY_s, RSAPUBKEY_MAGIC, PUBLICKEYSTRUC_s, bType_PUBLICKEYBLOB, \
     CUR_BLOB_VERSION, CALG_RSA_KEYX, PRIVATEKEYBLOB_MAGIC, PRIVATEKEYBLOB, bType_PRIVATEKEYBLOB, bType_PLAINTEXTKEYBLOB, \
-    bType_SIMPLEBLOB, CALG_RC4, CALG_AES_128, CALG_AES_192, CALG_AES_256, CALG_MD5, CALG_SHA1
-from wincrypto.util import add_pkcs5_padding, remove_pkcs5_padding
+    bType_SIMPLEBLOB, CALG_RC4, CALG_AES_128, CALG_AES_192, CALG_AES_256, CALG_MD5, CALG_SHA1, ALG_CLASS_HASH, \
+    ALG_CLASS_KEY_EXCHANGE, ALG_CLASS_DATA_ENCRYPT
+from wincrypto.util import add_pkcs5_padding, remove_pkcs5_padding, GET_ALG_CLASS
 
 
 class HCryptKey(object):
@@ -120,17 +121,15 @@ def export_plaintextkeyblob(self):
     def import_simpleblob(cls, data, hPubKey):
         assert struct.unpack('<I', data[:4])[0] == CALG_RSA_KEYX
         assert hPubKey
-        pkcs_1_encrypted_key = data[4:][::-1]
-        c = Crypto.Cipher.PKCS1_v1_5.new(hPubKey)
-        key = c.decrypt(pkcs_1_encrypted_key, None)
+        key = hPubKey.decrypt(data[4:])
         return cls(key)
 
     def export_simpleblob(self, rsa_key):
         result = PUBLICKEYSTRUC_s.pack(bType_SIMPLEBLOB, CUR_BLOB_VERSION, self.alg_id)
+        if rsa_key.alg_id != CALG_RSA_KEYX:
+            raise ValueError('SIMPLEBLOB export only supported under RSA key')
         result += struct.pack('<I', CALG_RSA_KEYX)
-        c = Crypto.Cipher.PKCS1_v1_5.new(rsa_key)
-        encrypted_key = c.encrypt(self.key)
-        result += encrypted_key[::-1]
+        result += rsa_key.encrypt(self.key)
         return result
 
 
@@ -203,7 +202,8 @@ class SHA1(HCryptHash):
     hash_class = hashlib.sha1
 
 
-symmetric_algorithms = [RC4, AES128, AES192, AES256]
-asymmetric_algorithms = [RSA_KEYX]
-hash_algorithms = [MD5, SHA1]
-algorithm_registry = dict((x.alg_id, x) for x in symmetric_algorithms + asymmetric_algorithms + hash_algorithms)
\ No newline at end of file
+algorithm_list = [RC4, AES128, AES192, AES256, RSA_KEYX, MD5, SHA1]
+symmetric_algorithms = [x for x in algorithm_list if GET_ALG_CLASS(x.alg_id) == ALG_CLASS_DATA_ENCRYPT]
+asymmetric_algorithms = [x for x in algorithm_list if GET_ALG_CLASS(x.alg_id) == ALG_CLASS_KEY_EXCHANGE]
+hash_algorithms = [x for x in algorithm_list if GET_ALG_CLASS(x.alg_id) == ALG_CLASS_HASH]
+algorithm_registry = dict((x.alg_id, x) for x in algorithm_list)
\ No newline at end of file
diff --git a/wincrypto/api.py b/wincrypto/api.py
index 42d5576..bd3120a 100644
--- a/wincrypto/api.py
+++ b/wincrypto/api.py
@@ -1,9 +1,9 @@
-from wincrypto import definitions
+from wincrypto import constants
 from wincrypto.algorithms import algorithm_registry
-from wincrypto.definitions import PUBLICKEYSTRUC, PUBLICKEYSTRUC_s, CUR_BLOB_VERSION, bType_PUBLICKEYBLOB, \
+from wincrypto.constants import PUBLICKEYSTRUC, PUBLICKEYSTRUC_s, CUR_BLOB_VERSION, bType_PUBLICKEYBLOB, \
     bType_PRIVATEKEYBLOB, bType_PLAINTEXTKEYBLOB, bType_SIMPLEBLOB, KP_KEYLEN, KP_ALGID, CALG_AES_192, CALG_AES_256, \
-    CALG_AES_128
-from wincrypto.util import derive_key_3des_aes
+    CALG_AES_128, ALG_CLASS_KEY_EXCHANGE, ALG_CLASS_DATA_ENCRYPT
+from wincrypto.util import derive_key_3des_aes, GET_ALG_CLASS
 
 
 def CryptImportKey(data, pub_key=None):
@@ -11,27 +11,30 @@ def CryptImportKey(data, pub_key=None):
     if publickeystruc.bVersion != CUR_BLOB_VERSION:
         raise NotImplementedError('PUBLICKEYSTRUC.bVersion={} not implemented'.format(publickeystruc.bVersion))
 
+    if publickeystruc.aiKeyAlg not in algorithm_registry:
+        raise NotImplementedError('ALG_ID {:x} not implemented'.format(publickeystruc.aiKeyAlg))
+
     if publickeystruc.bType == bType_PUBLICKEYBLOB:
-        if publickeystruc.aiKeyAlg not in algorithm_registry:
-            raise NotImplementedError('ALG_ID {:x} not implemented'.format(publickeystruc.aiKeyAlg))
+        if GET_ALG_CLASS(publickeystruc.aiKeyAlg) != ALG_CLASS_KEY_EXCHANGE:
+            raise ValueError('Invalid ALG_ID {:x} for PUBLICKEYBLOB'.format(publickeystruc.aiKeyAlg))
         return algorithm_registry[publickeystruc.aiKeyAlg].import_publickeyblob(data[8:])
 
-    if publickeystruc.bType == bType_PRIVATEKEYBLOB:
-        if publickeystruc.aiKeyAlg not in algorithm_registry:
-            raise NotImplementedError('ALG_ID {:x} not implemented'.format(publickeystruc.aiKeyAlg))
+    elif publickeystruc.bType == bType_PRIVATEKEYBLOB:
+        if GET_ALG_CLASS(publickeystruc.aiKeyAlg) != ALG_CLASS_KEY_EXCHANGE:
+            raise ValueError('Invalid ALG_ID {:x} for PRIVATEKEYBLOB'.format(publickeystruc.aiKeyAlg))
         return algorithm_registry[publickeystruc.aiKeyAlg].import_privatekeyblob(data[8:])
 
-    if publickeystruc.bType == bType_PLAINTEXTKEYBLOB:
-        if publickeystruc.aiKeyAlg not in algorithm_registry:
-            raise NotImplementedError('ALG_ID {:x} not implemented'.format(publickeystruc.aiKeyAlg))
+    elif publickeystruc.bType == bType_PLAINTEXTKEYBLOB:
+        if GET_ALG_CLASS(publickeystruc.aiKeyAlg) != ALG_CLASS_DATA_ENCRYPT:
+            raise ValueError('Invalid ALG_ID {:x} for PLAINTEXTKEYBLOB'.format(publickeystruc.aiKeyAlg))
         return algorithm_registry[publickeystruc.aiKeyAlg].import_plaintextkeyblob(data[8:])
 
-    if publickeystruc.bType == bType_SIMPLEBLOB:
-        if publickeystruc.aiKeyAlg not in algorithm_registry:
-            raise NotImplementedError('ALG_ID {:x} not implemented'.format(publickeystruc.aiKeyAlg))
+    elif publickeystruc.bType == bType_SIMPLEBLOB:
+        if GET_ALG_CLASS(publickeystruc.aiKeyAlg) != ALG_CLASS_DATA_ENCRYPT:
+            raise ValueError('Invalid ALG_ID {:x} for SIMPLEBLOB'.format(publickeystruc.aiKeyAlg))
         return algorithm_registry[publickeystruc.aiKeyAlg].import_simpleblob(data[8:], pub_key)
-
-    raise NotImplementedError('PUBLICKEYSTRUC.bType={} not implemented'.format(publickeystruc.bType))
+    else:
+        raise NotImplementedError('PUBLICKEYSTRUC.bType={} not implemented'.format(publickeystruc.bType))
 
 
 def CryptDecrypt(crypt_key, encrypted_data):
@@ -76,11 +79,11 @@ def CryptHashData(hash_alg, data):
 
 
 def CryptGetHashParam(hash_alg, dwParam):
-    if dwParam == definitions.HP_ALGID:
+    if dwParam == constants.HP_ALGID:
         return hash_alg.alg_id
-    elif dwParam == definitions.HP_HASHVAL:
+    elif dwParam == constants.HP_HASHVAL:
         return hash_alg.get_hash_val()
-    elif dwParam == definitions.HP_HASHSIZE:
+    elif dwParam == constants.HP_HASHSIZE:
         return hash_alg.get_hash_size()
     else:
         return NotImplementedError('hash param {} not implemented'.format(dwParam))
diff --git a/wincrypto/definitions.py b/wincrypto/constants.py
similarity index 89%
rename from wincrypto/definitions.py
rename to wincrypto/constants.py
index 03454c0..e6a6f31 100644
--- a/wincrypto/definitions.py
+++ b/wincrypto/constants.py
@@ -41,4 +41,8 @@
 
 CRYPT_EXPORTABLE = 1
 
-CUR_BLOB_VERSION = 2
\ No newline at end of file
+CUR_BLOB_VERSION = 2
+
+ALG_CLASS_DATA_ENCRYPT = 3 << 13
+ALG_CLASS_HASH = 4 << 13
+ALG_CLASS_KEY_EXCHANGE = 5 << 13
\ No newline at end of file
diff --git a/wincrypto/native.py b/wincrypto/native.py
index b475260..72a5d75 100644
--- a/wincrypto/native.py
+++ b/wincrypto/native.py
@@ -2,7 +2,7 @@
 from ctypes import windll, c_void_p, byref, create_string_buffer, c_int
 import struct
 
-from wincrypto.definitions import HP_ALGID, HP_HASHSIZE, KP_KEYLEN, KP_ALGID, CRYPT_EXPORTABLE
+from wincrypto.constants import HP_ALGID, HP_HASHSIZE, KP_KEYLEN, KP_ALGID, CRYPT_EXPORTABLE
 
 
 PROV_RSA_FULL = 1
diff --git a/wincrypto/util.py b/wincrypto/util.py
index b778d60..b50cac5 100644
--- a/wincrypto/util.py
+++ b/wincrypto/util.py
@@ -27,4 +27,8 @@ def derive_key_3des_aes(hash_alg):
     hash2 = CryptCreateHash(hash_alg.alg_id)
     hash2.hash_data(str(buf2))
     derived_key = hash1.get_hash_val() + hash2.get_hash_val()
-    return derived_key
\ No newline at end of file
+    return derived_key
+
+
+def GET_ALG_CLASS(x):
+    return x & (7 << 13)