main

main.py

@@ -0,0 +1,113 @@
+from cryptography.hazmat.primitives.asymmetric import ec
+
+from messenger import MessengerServer
+from messenger import MessengerClient
+
+def error(s):
+  print("=== ERROR: " + s)
+
+print("Initializing Server")
+server_sign_sk = ec.generate_private_key(ec.SECP256R1())
+server_enc_sk = ec.generate_private_key(ec.SECP256R1())
+server = MessengerServer(server_sign_sk, server_enc_sk)
+
+server_sign_pk = server_sign_sk.public_key()
+server_enc_pk = server_enc_sk.public_key()
+
+print("Initializing Users")
+alice = MessengerClient("alice", server_sign_pk, server_enc_pk)
+bob = MessengerClient("bob", server_sign_pk, server_enc_pk)
+carol = MessengerClient("carol", server_sign_pk, server_enc_pk)
+
+print("Generating Certs")
+certA = alice.generateCertificate()
+certB = bob.generateCertificate()
+certC = carol.generateCertificate()
+
+print("Signing Certs")
+sigA = server.signCert(certA)
+sigB = server.signCert(certB)
+sigC = server.signCert(certC)
+
+print("Distributing Certs")
+try:
+    alice.receiveCertificate(certB, sigB)
+    alice.receiveCertificate(certC, sigC)
+    bob.receiveCertificate(certA, sigA)
+    bob.receiveCertificate(certC, sigC)
+    carol.receiveCertificate(certA, sigA)
+    carol.receiveCertificate(certB, sigB)
+except:
+    error("certificate verification issue")
+
+print("Testing incorrect cert issuance")
+mallory = MessengerClient("mallory", server_sign_pk, server_enc_pk)
+certM = mallory.generateCertificate()
+try:
+    alice.receiveCertificate(certM, sigC)
+except:
+    print("successfully detected bad signature!")
+else:
+    error("accepted certificate with incorrect signature")
+
+print("Testing Reporting")
+content = "inappropriate message contents"
+reportPT, reportCT = alice.report("Bob", content)
+decryptedReport = server.decryptReport(reportCT)
+if decryptedReport != reportPT:
+    error("report did not decrypt properly")
+    print(reportPT)
+    print(decryptedReport)
+else:
+    print("Reporting test successful!")
+
+print("Testing a conversation")
+header, ct = alice.sendMessage("bob", "Hi Bob!")
+msg = bob.receiveMessage("alice", header, ct)
+if msg != "Hi Bob!":
+    error("message 1 was not decrypted correctly")
+
+header, ct = alice.sendMessage("bob", "Hi again Bob!")
+msg = bob.receiveMessage("alice", header, ct)
+if msg != "Hi again Bob!":
+    error("message 2  was not decrypted correctly")
+
+header, ct = bob.sendMessage("alice", "Hey Alice!")
+msg = alice.receiveMessage("bob", header, ct)
+if msg != "Hey Alice!":
+    error("message 3 was not decrypted correctly")
+
+header, ct = bob.sendMessage("alice", "Can't talk now")
+msg = alice.receiveMessage("bob", header, ct)
+if msg != "Can't talk now":
+    error("message 4 was not decrypted correctly")
+
+header, ct = bob.sendMessage("alice", "Started the homework too late :(")
+msg = alice.receiveMessage("bob", header, ct)
+if msg != "Started the homework too late :(":
+    error("message 5 was not decrypted correctly")
+
+header, ct = alice.sendMessage("bob", "Ok, bye Bob!")
+msg = bob.receiveMessage("alice", header, ct)
+if msg != "Ok, bye Bob!":
+    error("message 6  was not decrypted correctly")
+
+header, ct = bob.sendMessage("alice", "I'll remember to start early next time!")
+msg = alice.receiveMessage("bob", header, ct)
+if msg != "I'll remember to start early next time!":
+    error("message 7 was not decrypted correctly")
+
+print("conversation completed!")
+
+
+print("Testing handling an incorrect message")
+
+h, c = alice.sendMessage("bob", "malformed message test")
+m = bob.receiveMessage("alice", h, ct)
+if m != None:
+    error("didn't reject incorrect message")
+else:
+    print("success!")
+
+
+print("Testing complete")

messenger.py

@@ -0,0 +1,45 @@
+import os
+import pickle
+import string
+
+class MessengerServer:
+    def __init__(self, server_signing_key, server_decryption_key):
+        self.server_signing_key = server_signing_key
+        self.server_decryption_key = server_decryption_key
+
+    def decryptReport(self, ct):
+        raise Exception("not implemented!")
+        return
+
+    def signCert(self, cert):
+        raise Exception("not implemented!")
+        return
+
+class MessengerClient:
+
+    def __init__(self, name, server_signing_pk, server_encryption_pk):
+        self.name = name
+        self.server_signing_pk = server_signing_pk
+        self.server_encryption_pk = server_encryption_pk
+        self.conns = {}
+        self.certs = {}
+
+    def generateCertificate(self):
+        raise Exception("not implemented!")
+        return
+
+    def receiveCertificate(self, certificate, signature):
+        raise Exception("not implemented!")
+        return
+
+    def sendMessage(self, name, message):
+        raise Exception("not implemented!")
+        return
+
+    def receiveMessage(self, name, header, ciphertext):
+        raise Exception("not implemented!")
+        return
+
+    def report(self, name, message):
+        raise Exception("not implemented!")
+        return