create suspicious request detector and policy, add request to policy engine

passbook/suspicious_policy/models.py

@@ -0,0 +1,51 @@
+"""passbook suspicious request policy"""
+from django.db import models
+from django.utils.translation import gettext as _
+
+from passbook.core.models import Policy, User
+
+
+class SuspiciousRequestPolicy(Policy):
+    """Return true if request IP/target username's score is below a certain threshold"""
+
+    check_ip = models.BooleanField(default=True)
+    check_username = models.BooleanField(default=True)
+    threshold = models.IntegerField(default=-5)
+
+    form = 'passbook.suspicious_policy.forms.SuspiciousRequestPolicyForm'
+
+    def passes(self, user: User):
+        remote_ip = user.remote_ip
+        passing = True
+        if self.check_ip:
+            ip_scores = IPScore.objects.filter(ip=remote_ip, score__lte=self.threshold)
+            passing = passing and ip_scores.exists()
+        if self.check_username:
+            user_scores = UserScore.objects.filter(user=user, score__lte=self.threshold)
+            passing = passing and user_scores.exists()
+        return passing
+
+    class Meta:
+
+        verbose_name = _('Suspicious Request Policy')
+        verbose_name_plural = _('Suspicious Request Policies')
+
+class IPScore(models.Model):
+    """Store score coming from the same IP"""
+
+    ip = models.GenericIPAddressField(unique=True)
+    score = models.IntegerField(default=0)
+    updated = models.DateTimeField(auto_now=True)
+
+    def __str__(self):
+        return "IPScore for %s @ %d" % (self.ip, self.score)
+
+class UserScore(models.Model):
+    """Store score attempting to log in as the same username"""
+
+    user = models.OneToOneField(User, on_delete=models.CASCADE)
+    score = models.IntegerField(default=0)
+    updated = models.DateTimeField(auto_now=True)
+
+    def __str__(self):
+        return "UserScore for %s @ %d" % (self.user, self.score)