Implementing NoiseProtocol (WIP), binding crypto

noise/noise_protocol.py - added maps of cryptofunctions that will be
used, finished protocol name splitting

noise/patterns.py - added map of patterns

requirements.txt - switching to pycryptodome as a source of cipher and
hashing functions, and ed25519 package for that curve

noise/noise_protocol.py

@@ -1,19 +1,72 @@
+from functools import partial
+
+from .patterns import patterns_map
 from .constants import MAX_PROTOCOL_NAME_LEN
+from Crypto.Cipher import AES, ChaCha20
+from Crypto.Hash import BLAKE2b, BLAKE2s, SHA256, SHA512
+import ed25519
+
+dh_map = {
+    '25519': ed25519.create_keypair,
+    '448': None  # TODO implement
+}
+
+cipher_map = {
+    'AESGCM': partial(AES.new, mode=AES.MODE_GCM),
+    'ChaChaPoly': lambda key: ChaCha20.new(key=key)
+}
+
+hash_map = {
+    'BLAKE2b': BLAKE2b,  # TODO PARTIALS
+    'BLAKE2s': BLAKE2s,  # TODO PARTIALS
+    'SHA256': SHA256,  # TODO PARTIALS
+    'SHA512': SHA512  # TODO PARTIALS
+}
 
 
 class NoiseProtocol(object):
+    methods = {
+        'pattern': patterns_map,
+        'dh': dh_map,
+
+    }
     def __init__(self, protocol_name: bytes):
         if len(protocol_name) > MAX_PROTOCOL_NAME_LEN:
-            raise Exception('Protocol name too long, has to be at most {} chars long'.format(MAX_PROTOCOL_NAME_LEN))
+            raise ValueError('Protocol name too long, has to be at most {} chars long'.format(MAX_PROTOCOL_NAME_LEN))
 
-        self.pattern = None
+        self.name = protocol_name
+        data_dict = self._split_protocol_name()
+        self.pattern = patterns_map[data_dict['pattern']]
         self.pattern_modifiers = None
         self.dh = None
-        self.dh_modifiers = None
         self.cipher = None
-        self.cipher_modifiers = None
         self.hash = None
-        self.hash_modifiers = None
+
+    def _split_protocol_name(self):
+        unpacked = self.name.split('_')
+        if unpacked[0] != 'Noise':
+            raise ValueError(f'Noise protocol name shall begin with Noise! Provided: {self.name}')
+
+        pattern = ''
+        modifiers_str = None
+        for i, char in enumerate(unpacked[1]):
+            if char.isupper():
+                pattern += char
+            else:
+                modifiers_str = unpacked[1][i+1:]  # Will be empty string if it exceeds string size
+                break
+        modifiers = modifiers_str.split('+') if modifiers_str else []
+
+        data = {'pattern': 'Pattern' + pattern,
+                'dh': unpacked[2],
+                'cipher': unpacked[3],
+                'hash': unpacked[4],
+                'pattern_modifiers': modifiers}
+
+        # Validate if we know everything that Noise Protocol is supposed to use
+        # TODO validation
+
+        return data
 
 
 class KeyPair(object):

noise/patterns.py

@@ -168,3 +168,22 @@ class PatternIX(Pattern):
         [TOKEN_E, TOKEN_S],
         [TOKEN_E, TOKEN_EE, TOKEN_SE, TOKEN_S, TOKEN_ES]
     ]
+
+
+patterns_map = {
+    'PatternN': PatternN,
+    'PatternK': PatternN,
+    'PatternX': PatternN,
+    'PatternNN': PatternNN,
+    'PatternKN': PatternKN,
+    'PatternNK': PatternNK,
+    'PatternKK': PatternKK,
+    'PatternNX': PatternNX,
+    'PatternKX': PatternKX,
+    'PatternXN': PatternXN,
+    'PatternIN': PatternIN,
+    'PatternXK': PatternXK,
+    'PatternIK': PatternIK,
+    'PatternXX': PatternXX,
+    'PatternIX': PatternIX,
+}

requirements.txt

@@ -1,2 +1,3 @@
 pytest
-pynacl
+pycryptodome
+ed25519