Add support for Metadata property in Key.Activate (#67)

* First commit

* Update

* Update internal.py

* Update internal.py

* Update models.py

* Update setup.py

Author: artemlos

licensing/internal.py

@@ -70,28 +70,33 @@ def RSAVP1(pair, s):
         return pow(s, e, n)
 
     @staticmethod
-    def EMSA_PKCS1_V15_ENCODE(M, emLen):
+    def EMSA_PKCS1_V15_ENCODE(M, emLen, hlen = 256):
         import hashlib
         h = hashlib.sha256()
+        if hlen == 512:
+            h = hashlib.sha512()
         h.update(M)
         H = h.digest()
 
         T = bytes([0x30, 0x31, 0x30, 0x0d, 0x06, 0x09, 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x01, 0x05, 0x00, 0x04, 0x20]) + H
+        if hlen == 512:
+            T = bytes([0x30, 0x51, 0x30, 0x0d, 0x06, 0x09, 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x03, 0x05, 0x00, 0x04, 0x40]) + H
+       
         tLen = len(T)
         if emLen < tLen + 11:
             return None
         PS = bytes([0xff for _ in range(emLen - tLen - 3)])
         return b"".join([b"\x00\x01", PS, b"\x00", T])
-
+    
     @staticmethod
-    def RSAASSA_PKCS1_V15_VERIFY(pair, M, S):
+    def RSAASSA_PKCS1_V15_VERIFY(pair, M, S, l=256):
         n, e = pair
         s = HelperMethods.OS2IP(S)
         m = HelperMethods.RSAVP1((n,e), s)
         if m is None: return False
         EM = HelperMethods.I2OSP(m, 256)
         if EM is None: return False
-        EM2 = HelperMethods.EMSA_PKCS1_V15_ENCODE(M, 256)
+        EM2 = HelperMethods.EMSA_PKCS1_V15_ENCODE(M, 256, l) 
         if EM2 is None: return False
 
         try:
@@ -114,6 +119,23 @@ def verify_signature(response, rsaPublicKey):
 
         return HelperMethods.RSAASSA_PKCS1_V15_VERIFY((n,e), m, r)
 
+    @staticmethod
+    def verify_signature_metadata(signature, rsaPublicKey):
+        
+        import base64
+        import json
+        
+        n = HelperMethods.OS2IP(base64.b64decode(rsaPublicKey.modulus))
+        e = HelperMethods.OS2IP(base64.b64decode(rsaPublicKey.exponent))
+        
+        data = json.loads(base64.b64decode(signature))
+        
+        d = base64.b64decode(data["Data"])
+        s = base64.b64decode(data["Signature"])
+        
+        return [HelperMethods.RSAASSA_PKCS1_V15_VERIFY((n,e), d,s, l=512), d]
+        
+    
     @staticmethod
     def int2base64(num):
         return base64.b64encode(int.to_bytes(num), byteorder='big')

licensing/methods.py

@@ -61,7 +61,21 @@ def activate(token, rsa_pub_key, product_id, key, machine_code, fields_to_return
         else:
             try:
                 if HelperMethods.verify_signature(response, pubkey):
-                    return (LicenseKey.from_response(response), response.message)
+                    if metadata:
+                        
+                        try:
+                            metadata_s = HelperMethods.verify_signature_metadata(response.metadata["signature"], pubkey)
+                        
+                            if metadata_s[0]:
+                                return (LicenseKey.from_response(response), response.message, json.loads(metadata_s[1]))
+                            else:
+                                return (LicenseKey.from_response(response), response.message, "Signature check for metadata object failed.")
+                        except:
+                            return (LicenseKey.from_response(response), response.message, "Signature check for metadata object failed.")
+
+                                
+                    else:
+                        return (LicenseKey.from_response(response), response.message)
                 else:
                     return (None, "The signature check failed.")
             except Exception as ex:

licensing/models.py

@@ -164,11 +164,12 @@ def __load_activated_machines(obj):
 
 class Response:
 
-    def __init__(self, license_key, signature, result, message):
+    def __init__(self, license_key, signature, result, message, metadata=None):
         self.license_key = license_key
         self.signature = signature
         self.result = result
         self.message = message
+        self.metadata = metadata
 
     @staticmethod
     def from_string(responseString):        
@@ -178,6 +179,7 @@ def from_string(responseString):
         signature = ""
         result = 0
         message = ""
+        metadata = None
 
         if "licensekey" in obj:
             licenseKey = obj["licensekey"]
@@ -192,8 +194,13 @@ def from_string(responseString):
             result = obj["result"]
         else:
             result = 1
+            
+        if "metadata" in obj:
+            metadata = obj["metadata"]
+            
+
 
-        return Response(licenseKey, signature, result, message)
+        return Response(licenseKey, signature, result, message, metadata)
 
 class RSAPublicKey:
 

setup.py

@@ -2,13 +2,13 @@
 setup(
   name = 'licensing',         # How you named your package folder (MyLib)
   packages = ['licensing'],   # Chose the same as "name"
-  version = '0.41',      # Start with a small number and increase it with every change you make
+  version = '0.42',      # Start with a small number and increase it with every change you make
   license='MIT',        # Chose a license from here: https://help.github.com/articles/licensing-a-repository
   description = 'Client library for Cryptolens licensing Web API.',   # Give a short description about your library
   author = 'Cryptolens AB',                   # Type in your name
   author_email = '[email protected]',      # Type in your E-Mail
   url = 'https://cryptolens.io',   # Provide either the link to your github or to your website
-  download_url = 'https://github.com/Cryptolens/cryptolens-python/archive/v_41.tar.gz',    # I explain this later on
+  download_url = 'https://github.com/Cryptolens/cryptolens-python/archive/v_42.tar.gz',    # I explain this later on
   keywords = ['software licensing', 'licensing library', 'cryptolens'],   # Keywords that define your package best
   classifiers=[
     #'Development Status :: 5 - Stable',      # Chose either "3 - Alpha", "4 - Beta" or "5 - Production/Stable" as the current state of your package