adding password generator

sys/passgen.py

@@ -0,0 +1,97 @@
+#!/usr/bin/env python3
+
+# Thanks to https://gist.github.com/stantonk/7268449
+# See also:
+# http://stackoverflow.com/questions/5480131/will-python-systemrandom-os-urandom-always-have-enough-entropy-for-good-crypto
+import argparse
+import random
+import re
+import string
+
+class genPass(object):
+    def __init__(self, case = None, charset = 'complex', passlen = 32, quotes = True, backslashes = True,
+                 human = False):
+        # complex is symbols and mixed-case alphanumeric
+        # simple is mixed-case alphanumeric
+        _alphanum = string.ascii_letters + string.digits
+        chars = {'complex': _alphanum + string.punctuation,
+                 'simple': _alphanum}
+        self.chars = chars[charset]
+        if not quotes:
+            self.chars = re.sub('["\']', '', self.chars)
+        if not backslashes:
+            self.chars = re.sub('\\\\', '', self.chars)
+        if human:
+            _dupechars = ['`', "'", '|', 'l', 'I', 'i', 'l', '1', 'o', '0', 'O']
+            self.chars = ''.join(sorted(list(set(self.chars) - set(_dupechars))))
+        if case == 'upper':
+            self.chars = self.chars.upper()
+        elif case == 'lower':
+            self.chars = self.chars.lower()
+        self.chars = ''.join(sorted(list(set(self.chars))))
+        self.passlen = passlen
+
+    def generate(self):
+        self.pw = ''
+        for _ in range(self.passlen):
+            self.pw += random.SystemRandom().choice(self.chars)
+
+def parseArgs():
+    args = argparse.ArgumentParser(description = 'A password generator.')
+    args.add_argument('-t', '--type',
+                      dest = 'passtype',
+                      choices = ['simple', 'complex'],  # chars in genPass
+                      default = 'complex',
+                      help = ('Whether to generate "simple" (no symbols, '
+                              'safer for e.g. databases) password(s) or more complex ones. The default is "complex"'))
+    args.add_argument('-l', '--length',
+                      dest = 'passlen',
+                      metavar = 'LENGTH',
+                      type = int,
+                      default = 32,
+                      help = ('The length of the password(s) to generate. The default is 32'))
+    args.add_argument('-c', '--count',
+                      dest = 'passcount',
+                      metavar = 'COUNT',
+                      type = int,
+                      default = 1,
+                      help = ('The number of passwords to generate. The default is 1'))
+    args.add_argument('-q', '--no-quotes',
+                      dest = 'quotes',
+                      action = 'store_false',
+                      help = ('If specified, strip out quotation marks (both " and \') from the passwords. '
+                              'Only relevant if -t/--type is complex, as simple types don\'t contain these'))
+    args.add_argument('-b', '--no-backslashes',
+                      dest = 'backslashes',
+                      action = 'store_false',
+                      help = ('If specified, strip out backslashes. Only relevant if -t/--type is complex, as '
+                              'simple types don\'t contain these'))
+    args.add_argument('-H', '--human',
+                      dest = 'human',
+                      action = 'store_true',
+                      help = ('If specified, make the passwords easier to read by human eyes (i.e. no 1 and l, '
+                              'o or O or 0, etc.)'))
+    caseargs = args.add_mutually_exclusive_group()
+    caseargs.add_argument('-L', '--lower',
+                          dest = 'case',
+                          action = 'store_const',
+                          const = 'lower',
+                          help = 'If specified, make password all lowercase')
+    caseargs.add_argument('-U', '--upper',
+                          dest = 'case',
+                          action = 'store_const',
+                          const = 'upper',
+                          help = 'If specified, make password all UPPERCASE')
+    return(args)
+
+def main():
+    args = vars(parseArgs().parse_args())
+    for _ in range(0, args['passcount']):
+        p = genPass(charset = args['passtype'], passlen = args['passlen'],
+                    quotes = args['quotes'], backslashes = args['backslashes'],
+                    human = args['human'], case = args['case'])
+        p.generate()
+        print(p.pw)
+
+if __name__ == '__main__':
+    main()