From 72b7b3382571df4df0d0a7848d1d460a3327b86e Mon Sep 17 00:00:00 2001
From: Fredrik Wahlberg <fredrik.wahlberg@evry.com>
Date: Fri, 13 Jul 2018 11:27:48 +0200
Subject: [PATCH] Startar med en kodsnutt jag hittade

---
 README.md |  3 +++
 totp.py   | 69 +++++++++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 72 insertions(+)
 create mode 100644 README.md
 create mode 100644 totp.py

diff --git a/README.md b/README.md
new file mode 100644
index 0000000..b45be2b
--- /dev/null
+++ b/README.md
@@ -0,0 +1,3 @@
+TOTP
+
+Tanken är att det ska bli ett cli-verktyg för att generera tokens från andOtps backupfiler
\ No newline at end of file
diff --git a/totp.py b/totp.py
new file mode 100644
index 0000000..be07e3d
--- /dev/null
+++ b/totp.py
@@ -0,0 +1,69 @@
+#!/usr/bin/env python
+
+from __future__ import print_function
+import base64
+import hashlib
+import hmac
+import struct
+import sys
+import time
+
+
+class TOTP():
+    class TOTPException(Exception):
+	def __init__(self, msg):
+	    self.msg = msg
+
+	def __str__(self):
+            return repr(self.msg)
+
+
+    def __init__(self, secret):
+        if not secret:
+            raise TOTP.TOTPException('Invalid secret')
+        self.secret = secret
+
+    def generate(self):
+        try:
+            key = base64.b32decode(self.secret)
+	    num = int(time.time()) // 30
+            msg = struct.pack('>Q', num)
+
+            # Take a SHA1 HMAC of key and binary-packed time value
+	    digest = hmac.new(key, msg, hashlib.sha1).digest()
+
+	    # Last 4 bits of the digest tells which 4 bytes to use
+            offset = ord(digest[19]) & 15
+            token_base = digest[offset : offset+4]
+
+	    # Unpack that into an integer and strip it down
+            token_val = struct.unpack('>I', token_base)[0] & 0x7fffffff
+	    token_num = token_val % 1000000
+
+	    # Pad with leading zeroes
+            token = '{0:06d}'.format(token_num)
+
+            return token
+        except:
+            raise TOTP.TOTPException('Invalid secret')
+
+
+def main(args):
+    if len(args):
+        token = sys.stdin.readline().strip() if args[0] == '-' else args[0]
+    elif not sys.stdin.isatty():
+        token = sys.stdin.readline().strip()
+    else:
+        return 'Usage: totp <secret>'
+
+    try:
+        print(TOTP(token).generate())
+    except TOTP.TOTPException as e:
+	return 'Error: ' + e.msg
+
+
+if __name__ == '__main__':
+    try:
+        sys.exit(main(sys.argv[1:]))
+    except KeyboardInterrupt:
+        sys.exit(1)