johnwheeler · July 28, 2016 19:06 · Jul 28, 2016
diff --git a/gistfile1.txt b/gistfile1.txt
@@ -0,0 +1,50 @@
+import os
+import base64
+import posixpath
+from datetime import datetime
+from six.moves.urllib.parse import urlparse
+from six.moves.urllib.request import urlopen
+
+from . import logger
+
+
+class VerificationError(Exception): pass
+
+
+
+def verify_timestamp(timestamp):
+    dt = datetime.utcnow() - timestamp.replace(tzinfo=None)
+    if dt.seconds > 150:
+        raise VerificationError("Timestamp verification failed")
+
+
+def verify_application_id(candidate, records):
+    if candidate not in records:
+        raise VerificationError("Application ID verification failed")
+
+
+def _valid_certificate_url(cert_url):
+    parsed_url = urlparse(cert_url)
+    if parsed_url.scheme == 'https':
+        if parsed_url.hostname == "s3.amazonaws.com":
+            if posixpath.normpath(parsed_url.path).startswith("/echo.api/"):
+                return True
+    return False
+
+
+def _valid_certificate(cert):
+    not_after = cert.get_notAfter().decode('utf-8')
+    not_after = datetime.strptime(not_after, '%Y%m%d%H%M%SZ')
+    if datetime.utcnow() >= not_after:
+        return False
+    found = False
+    for i in range(0, cert.get_extension_count()):
+        extension = cert.get_extension(i)
+        short_name = extension.get_short_name().decode('utf-8')
+        value = str(extension)
+        if 'subjectAltName' == short_name and 'DNS:echo-api.amazon.com' == value:
+                found = True
+                break
+    if not found:
+        return False
+    return True