Now works.. Bob would send 0 for false, which encrypts to 0.....

week4.py

@@ -4,7 +4,7 @@
 
 from secrets import SystemRandom
 import numpy as np
-from crypto.week1 import BloodType, convert_from_string_to_enum, blood_cell_compatibility_lookup
+from crypto.week1 import BloodType, blood_cell_compatibility_lookup
 
 # We can't encrypt 0, so we have to index from 1
 convert_bloodtype_to_index = {
@@ -67,6 +67,9 @@ class Alice:
 
         self.sk = elgamal.gen_key()
         self.pk = elgamal.gen(self.sk)
+        # There is 100% a better way to get the index, also, it's to avoid encryption 0. Coincidentally, it's
+        # not an issue when we do it, as O- is in the 0th index and this bloodtype can donate to everyone
+        # so the decryption bugging, it not an issue
         self.b = list(convert_bloodtype_to_index.keys()).index(bloodtype)+1
         self.fake_pks = [self.elgamal.ogen()
                          for _ in range(7)]
@@ -77,8 +80,10 @@ class Alice:
         return all_pks
 
     def retrieve(self, ciphers):
+        print(ciphers)
         mb = self.elgamal.dec(ciphers[self.b-1])
-        return mb
+        # Bog sends 1 for false, 2 for true, so we have to subtract 1 here
+        return mb-1
 
 
 class Bob:
@@ -87,6 +92,7 @@ class Bob:
         self.truth_vals = []
         self.elgamal = elgamal
         self.pks = None
+        # Bob needs his row of the truth table, to create the 8 messages
         for donor in BloodType:
             truth_val = blood_cell_compatibility_lookup(bloodtype, donor)
             self.truth_vals.append(truth_val)
@@ -98,18 +104,18 @@ class Bob:
         ciphers = []
         for idx, truth_val in enumerate(self.truth_vals):
             pk = self.pks[idx]
-            c = self.elgamal.enc(truth_val, pk)
+            # Bob can't send 0, as it will encrypt to 0
+            c = self.elgamal.enc(truth_val+1, pk)
             ciphers.append(c)
         return ciphers
 
 
 def run(donor : BloodType, recipient : BloodType):
-    p = 199
+    p = 35977
     q = 2 * p + 1
     g = SystemRandom().randint(2, q)
 
     elgamal = ElGamal(g, q, p)
-
     alice = Alice(donor, elgamal)
     bob = Bob(recipient, elgamal)
 
@@ -120,7 +126,9 @@ def run(donor : BloodType, recipient : BloodType):
 
 
 if __name__ == "__main__":
-    # 199 is a large prime
+    #z = run(BloodType.O_POSITIVE, BloodType.A_NEGATIVE)
+    #print(z)
+    #exit()
 
     green = 0
     red = 0