huge commit

2026/cscg/crypto/dino-vault/app.py

@@ -0,0 +1,152 @@
+import os
+import socketserver
+from dataclasses import dataclass
+from Crypto.Util.number import getPrime, long_to_bytes, bytes_to_long
+
+FLAG = os.getenv("FLAG", "fake_flag")
+print(FLAG)
+
+primesize = 2048
+
+@dataclass
+class Dino:
+    name: str
+    dna: str
+    vault_key: int
+
+    @staticmethod
+    def to_dna(dinosaur_information: str):
+        lookup = ["A", "T", "G", "C"]
+        dna = []
+        for c in dinosaur_information:
+            c = ord(c)
+            for _ in range(4):
+                dna.append(lookup[c & 3])
+                c >>= 2
+        return "".join(dna)
+
+    def get_encrypted_dna(self):
+        transmission_key = getPrime(primesize)
+        dinosaur_modulation_index = transmission_key * self.vault_key
+        evergreen_number = 2**16 + 1
+        resampled_dna = pow(bytes_to_long(self.dna.encode()), evergreen_number, dinosaur_modulation_index)
+        encrypted_dna = long_to_bytes(resampled_dna).hex()
+        return encrypted_dna, dinosaur_modulation_index
+
+class DinoVaultServer(socketserver.StreamRequestHandler):
+    def write(self, string):
+        self.wfile.write(f"{string}\n".encode())
+
+    def read(self):
+        return self.rfile.readline().rstrip().decode("utf-8")
+
+    def read_int(self):
+        line = self.read()
+        try:
+            ret = int(line)
+            return ret
+        except ValueError:
+            return 0
+        return 0
+
+    def prepare_dinos(self):
+        self.dinos = [
+            Dino(name="Vexillum Rex",  dna=Dino.to_dna(f"Has a crown and {FLAG} written on its back"), vault_key=getPrime(primesize)),
+            Dino(name="Pedosaurus",    dna=Dino.to_dna("Has giant feet"), vault_key=getPrime(primesize)),
+            Dino(name="Despotiraptor", dna=Dino.to_dna("Slightly sus ethics"), vault_key=getPrime(primesize)),
+            Dino(name="Planosaurus",   dna=Dino.to_dna("Is floored when nothing goes to plan"), vault_key=getPrime(primesize)),
+        ]
+
+    def create(self):
+        self.write("What is your dinosaur called?")
+        name = self.read()
+        self.write(f"Please give me all the information about {name}")
+        info = self.read()
+        self.write("Thanks, we have now sequenced your dinosaur.")
+        vault_key = getPrime(primesize)
+        self.write(f"To access your dino, you will need this key: {vault_key}")
+        self.dinos.append(Dino(name=name, dna=Dino.to_dna(info), vault_key=vault_key))
+
+    def view(self):
+        self.write("We have the following selection of dinosaurs available:")
+        for dino in self.dinos:
+            self.write(f"- {dino.name}")
+
+    def download(self):
+        self.write("Which encrypted dinosaur-DNA do you want to download?")
+        name = self.read()
+        for dino in self.dinos:
+            if name == dino.name:
+                break
+        else:
+            self.write("Could not find the dino you were looking for")
+            return
+        self.write("Here is the encrypted DNA you wanted:")
+        enc_dna, mod_index = dino.get_encrypted_dna()
+        self.write(enc_dna)
+        self.write("Use your vault key alongside the modulation index to access the DNA:")
+        self.write(mod_index)
+
+    def menu(self):
+        self.write("")
+        self.write("You can:")
+        self.write(" 1. Create your own Dino")
+        self.write(" 2. View all available dinos")
+        self.write(" 3. Download the DNA of a dino")
+        self.write(" 4. Exit")
+
+    def welcome(self):
+        self.write("Hello and welcome to the")
+        self.banner()
+        self.write("")
+        self.write("Here, you can give us your 🦕 and we extract and store DNA samples for all your cloning needs.")
+        self.write("Make sure to back up your creations before the next apocalypse!")
+
+    def banner(self):
+        self.write("""
+🌋🌋🌋🌋🌋🦕🦕🦕🌋🌋🌋🦕🦕🌋🦕🦕🦕🦕🌋🦕🦕🦕🌋🌋🌋🦕🦕🦕🦕🌋🌋🌋🦕🦕🦕🦕🦕🌋🌋🦕🦕🦕🦕🌋🦕🦕🦕🌋🦕🦕🌋🌋🌋🌋🦕
+🦕🌋🦕🦕🦕🌋🦕🦕🦕🌋🦕🦕🦕🌋🦕🦕🦕🦕🌋🦕🦕🌋🦕🦕🦕🌋🦕🦕🌋🦕🦕🦕🌋🦕🦕🦕🌋🦕🦕🌋🦕🦕🦕🌋🦕🦕🦕🌋🦕🦕🌋🦕🦕🦕🌋
+🦕🌋🦕🦕🦕🌋🦕🦕🦕🌋🦕🦕🦕🌋🌋🦕🦕🦕🌋🦕🦕🌋🦕🦕🦕🌋🦕🦕🌋🦕🦕🦕🦕🦕🦕🌋🦕🦕🦕🦕🌋🦕🦕🌋🦕🦕🦕🌋🦕🦕🌋🦕🦕🦕🌋
+🦕🌋🦕🦕🦕🌋🦕🦕🦕🌋🦕🦕🦕🌋🦕🌋🦕🦕🌋🦕🦕🌋🦕🦕🦕🌋🦕🦕🌋🦕🦕🦕🦕🦕🦕🌋🦕🦕🦕🦕🌋🦕🦕🌋🦕🦕🦕🌋🦕🦕🌋🦕🦕🦕🌋
+🦕🌋🦕🦕🦕🌋🦕🦕🦕🌋🦕🦕🦕🌋🦕🦕🌋🦕🌋🦕🦕🌋🦕🦕🦕🌋🦕🦕🦕🌋🌋🌋🦕🦕🦕🌋🦕🦕🦕🦕🌋🦕🦕🌋🦕🦕🦕🌋🦕🦕🌋🌋🌋🌋🦕
+🦕🌋🦕🦕🦕🌋🦕🦕🦕🌋🦕🦕🦕🌋🦕🦕🦕🌋🌋🦕🦕🌋🦕🦕🦕🌋🦕🦕🦕🦕🦕🦕🌋🦕🦕🌋🌋🌋🌋🌋🌋🦕🦕🌋🦕🦕🦕🌋🦕🦕🌋🌋🦕🦕🦕
+🦕🌋🦕🦕🦕🌋🦕🦕🦕🌋🦕🦕🦕🌋🦕🦕🦕🦕🌋🦕🦕🌋🦕🦕🦕🌋🦕🦕🦕🦕🦕🦕🌋🦕🦕🌋🦕🦕🦕🦕🌋🦕🦕🌋🦕🦕🦕🌋🦕🦕🌋🦕🌋🦕🦕
+🦕🌋🦕🦕🦕🌋🦕🦕🦕🌋🦕🦕🦕🌋🦕🦕🦕🦕🌋🦕🦕🌋🦕🦕🦕🌋🦕🦕🌋🦕🦕🦕🌋🦕🦕🌋🦕🦕🦕🦕🌋🦕🦕🌋🦕🦕🦕🌋🦕🦕🌋🦕🦕🌋🦕
+🌋🌋🌋🌋🌋🦕🦕🦕🌋🌋🌋🦕🦕🌋🦕🦕🦕🦕🌋🦕🦕🦕🌋🌋🌋🦕🦕🦕🦕🌋🌋🌋🦕🦕🦕🌋🦕🦕🦕🦕🌋🦕🦕🦕🌋🌋🌋🦕🦕🦕🌋🦕🦕🦕🌋
+                   """)
+        self.write("Vault")
+
+    def handle_choice(self, choice):
+        match choice:
+            case 1:
+                self.create()
+                return True
+            case 2:
+                self.view()
+                return True
+            case 3:
+                self.download()
+                return True
+            case 4:
+                self.write("See you soon at the")
+                self.banner()
+                return False
+            case _:
+                self.menu()
+                return True
+
+    def handle(self):
+        self.prepare_dinos()
+        self.banner()
+        self.menu()
+
+        choice = self.read_int()
+        while self.handle_choice(choice):
+            self.write("What do you want to do now?")
+            choice = self.read_int()
+        
+
+if __name__ == "__main__":
+    HOST, PORT = "0.0.0.0", 5000
+    with socketserver.ThreadingTCPServer((HOST, PORT), DinoVaultServer) as server:
+        server.serve_forever()