#8 user first login view

apps/users/utils.py

@@ -1,18 +1,18 @@
 # ~*~ coding: utf-8 ~*~
 #
-
 from __future__ import unicode_literals
-import os
 import logging
+import os
+import re
 
-from paramiko.rsakey import RSAKey
 from django.contrib.auth.mixins import UserPassesTestMixin
 from django.urls import reverse_lazy
 from django.utils.translation import ugettext as _
 
+from paramiko.rsakey import RSAKey
+
 from common.tasks import send_mail_async
 from common.utils import reverse
-from users.models import User
 
 
 try:
@@ -125,5 +125,56 @@ def send_reset_password_mail(user):
     send_mail_async.delay(subject, message, recipient_list, html_message=message)
 
 
+def validate_ssh_pk(text):
+    """
+    Expects a SSH private key as string.
+    Returns a boolean and a error message.
+    If the text is parsed as private key successfully,
+    (True,'') is returned. Otherwise,
+    (False, <message describing the error>) is returned.
 
+    from https://github.com/githubnemo/SSH-private-key-validator/blob/master/validate.py
 
+    """
+
+    if not text:
+        return False, 'No text given'
+
+    startPattern = re.compile("^-----BEGIN [A-Z]+ PRIVATE KEY-----")
+    optionPattern = re.compile("^.+: .+")
+    contentPattern = re.compile("^([a-zA-Z0-9+/]{64}|[a-zA-Z0-9+/]{1,64}[=]{0,2})$")
+    endPattern = re.compile("^-----END [A-Z]+ PRIVATE KEY-----")
+
+    def contentState(text):
+        for i in range(0, len(text)):
+            line = text[i]
+
+            if endPattern.match(line):
+                if i == len(text) - 1 or len(text[i + 1]) == 0:
+                    return True, ''
+                else:
+                    return False, 'At end but content coming'
+
+            elif not contentPattern.match(line):
+                return False, 'Wrong string in content section'
+
+        return False, 'No content or missing end line'
+
+    def optionState(text):
+        for i in range(0, len(text)):
+            line = text[i]
+
+            if line[-1:] == '\\':
+                return optionState(text[i + 2:])
+
+            if not optionPattern.match(line):
+                return contentState(text[i + 1:])
+
+        return False, 'Expected option, found nothing'
+
+    def startState(text):
+        if len(text) == 0 or not startPattern.match(text[0]):
+            return False, 'Header is wrong'
+        return optionState(text[1:])
+
+    return startState([n.strip() for n in text.splitlines()])