Include msuksong's changes for encrypting, as well

README.md

@@ -0,0 +1,36 @@
+# Junos $9$ secrets encrypt/decrypt script
+
+## Usage
+```
+$ python junosdecode.py
+usage: junosdecode.py [-h] [-v] [-e PLAINTEXT | -d SECRET]
+
+Junos $9$ password en/decrypt script
+
+optional arguments:
+  -h, --help            show this help message and exit
+  -v, --version         show program's version number and exit
+  -e PLAINTEXT, --encrypt PLAINTEXT
+                        encrypt plaintext
+  -d SECRET, --decrypt SECRET
+                        decrypt secret
+```
+
+## Examples
+```
+$ python junosdecode.py -e 'hello'
+Junos $9$ secrets en/decrypter
+python version by matt hite/min song
+original perl version by kevin brintnall
+
+plaintext version: hello
+encrypted version: $9$lateMXVb2JGi7-Dk
+
+$ python junosdecode.py -d '$9$lateMXVb2JGi7-Dk'
+Junos $9$ secrets en/decrypter
+python version by matt hite/min song
+original perl version by kevin brintnall
+
+encrypted version: $9$lateMXVb2JGi7-Dk
+decrypted version: hello
+```

junosdecode.py

@@ -11,8 +11,15 @@
 ## version 1.0
 ##
 
+#############################################################################
+## added juniper_encrypt and the necessary functions
+## by Minsuk Song <msuk.song@gmail.com>, who also knows
+## very little perl
+##
+
 import sys
-from optparse import OptionParser, OptionGroup
+import argparse
+import random
 
 #################################################################
 ## globals
@@ -80,23 +87,75 @@ def juniper_decrypt(crypt):
         decrypt += _gap_decode(gaps, decode)
     return decrypt
 
+def _reverse(my_list):
+    new_list = list(my_list)
+    new_list.reverse()
+    return new_list
+
+def _gap_encode(pc, prev, encode):
+    _ord = ord(pc)
+
+    crypt = ''
+    gaps = []
+    for mod in _reverse(encode):
+        gaps.insert(0, int(_ord/mod))
+        _ord %= mod
+
+    for gap in gaps:
+        gap += ALPHA_NUM[prev] + 1
+        prev = NUM_ALPHA[gap % len(NUM_ALPHA)]
+        crypt += prev
+
+    return crypt
+
+def _randc(cnt = 0):
+    ret = ""
+    for _ in range(cnt):
+        ret += NUM_ALPHA[random.randrange(len(NUM_ALPHA))]
+    return ret
+
+def juniper_encrypt(plaintext, salt = None):
+    if salt is None:
+        salt = _randc(1)
+    rand = _randc(EXTRA[salt])
+
+    pos = 0
+    prev = salt
+    crypt = MAGIC + salt + rand
+
+    for x in plaintext:
+        encode = ENCODING[pos % len(ENCODING)]
+        crypt += _gap_encode(x, prev, encode)
+        prev = crypt[-1]
+        pos += 1
+
+    return crypt
+
 
 def main():
-    parser = OptionParser(usage="usage: %prog [options] encrypted_string",
+    parser = argparse.ArgumentParser(description="Junos $9$ password en/decrypt script",
                           version="1.0")
+    group = parser.add_mutually_exclusive_group()
+    group.add_argument("-e", "--encrypt", dest="plaintext", help="encrypt plaintext")
+    group.add_argument("-d", "--decrypt", dest="secret", help="decrypt secret")
 
-    (options, args) = parser.parse_args()
-
-    # right number of arguments?
-    if len(args) < 1:
-        parser.error("wrong number of arguments")
+    if len(sys.argv) == 1:
+        parser.print_help()
+        sys.exit(1)
+    args = parser.parse_args()
 
-    encrypted_string = args[0]
-    print "junos password decrypter"
-    print "python version by matt hite"
+    print "Junos $9$ secrets en/decrypter"
+    print "python version by matt hite/min song"
     print "original perl version by kevin brintnall\n"
-    print "encrypted version: %s" % encrypted_string
-    print "decrypted version: %s" % juniper_decrypt(encrypted_string)
+    if args.secret:
+        encrypted_string = args.secret
+        print "encrypted version: %s" % encrypted_string
+        print "decrypted version: %s" % juniper_decrypt(encrypted_string)
+    elif args.plaintext:
+        plaintext_string = args.plaintext
+        print "plaintext version: %s" % plaintext_string
+        print "encrypted version: %s" % juniper_encrypt(plaintext_string)
+
 
 if __name__ == "__main__":
     main()