Add script rsa_authentifcation

algebre-non-lineaire/rsa_authentication.py

@@ -0,0 +1,55 @@
+#!/usr/bin/env python3
+
+"""Signature et vérification de signature avec RSA"""
+
+import sys
+
+
+def main() -> None:
+    """Call functions dependending on args"""
+
+    if len(sys.argv) == 1:
+        command = input("command: ")
+    else:
+        command = sys.argv[1]
+    if command == "sign":
+        ac = int(input("AC : "))
+        d = int(input("d : "))
+        nd = int(input("nd : "))
+        e = int(input("e : "))
+        ne = int(input("ne : "))
+        s = sign(ac, d, e, nd, ne)
+        print(s)
+    elif command == "verify":
+        s = int(input("S : "))
+        ac = int(input("AC : "))
+        d = int(input("d : "))
+        nd = int(input("nd : "))
+        e = int(input("e : "))
+        ne = int(input("ne : "))
+        if verify(s, ac, d, e, nd, ne):
+            print("YES")
+        else:
+            print("NO")
+
+
+def sign(ac: int, d: int, e: int, nd: int, ne: int) -> int:
+    """Produce a signature"""
+
+    if nd <= ne:
+        return pow(pow(ac, d, nd), e, ne)
+    return pow(pow(ac, e, ne), d, nd)
+
+
+def verify(s: int, ac: int, d: int, e: int, nd: int, ne: int) -> bool:
+    """Verify a signature"""
+
+    if nd >= ne:
+        maybe = pow(pow(s, d, nd), e, ne)
+    else:
+        maybe = pow(pow(s, e, ne), d, nd)
+    print(f"Found AC = {maybe}")
+    return maybe == ac
+
+if __name__ == "__main__":
+    main()