Merge pull request mjs#270 from growbots/filter-imaplib-login

Prevent IMAP passwords from going to the logging system

Author: mjs

imapclient/imapclient.py

@@ -12,7 +12,7 @@
 import re
 from datetime import datetime, date
 from operator import itemgetter
-from logging import getLogger
+from logging import LoggerAdapter, getLogger
 
 from six import moves, iteritems, text_type, integer_types, PY3, binary_type, iterbytes
 
@@ -30,7 +30,6 @@
 
 
 logger = getLogger(__name__)
-imaplib_logger = getLogger('imapclient.imaplib')
 
 __all__ = ['IMAPClient', 'DELETED', 'SEEN', 'ANSWERED', 'FLAGGED', 'DRAFT', 'RECENT']
 
@@ -150,6 +149,9 @@ def __init__(self, host, port=None, use_uid=True, ssl=False, stream=False,
         logger.debug("Connected to host %s", self.host)
 
         # Small hack to make imaplib log everything to its own logger
+        imaplib_logger = IMAPlibLoggerAdapter(
+            getLogger('imapclient.imaplib'), dict()
+        )
         self._imap.debug = 5
         self._imap._mesg = imaplib_logger.debug
 
@@ -1508,3 +1510,17 @@ def debug_trunc(v, maxlen):
         return repr(v)
     hl = maxlen // 2
     return repr(v[:hl])  + "..." + repr(v[-hl:])
+
+
+class IMAPlibLoggerAdapter(LoggerAdapter):
+    """Adapter preventing IMAP secrets from going to the logging facility."""
+
+    def process(self, msg, kwargs):
+        for command in ("LOGIN", "AUTHENTICATE"):
+            if msg.startswith(">") and command in msg:
+                msg_start = msg.split(command)[0]
+                msg = "{}{} **REDACTED**".format(msg_start, command)
+                break
+        return super(IMAPlibLoggerAdapter, self).process(
+            msg, kwargs
+        )

tests/test_imapclient.py

@@ -12,6 +12,7 @@
 
 import six
 
+from imapclient.imapclient import IMAPlibLoggerAdapter
 from imapclient.fixed_offset import FixedOffset
 from .testable_imapclient import TestableIMAPClient as IMAPClient
 from .imapclient_test import IMAPClientTest
@@ -365,6 +366,27 @@ def test_IMAP_is_patched(self):
         self.client._imap._mesg('two')
         self.assertIn('DEBUG:imapclient.imaplib:two', log_stream.getvalue())
 
+    def test_redacted_password(self):
+        logger_mock = Mock()
+        logger_mock.manager.disable = logging.DEBUG
+        logger_mock.getEffectiveLevel.return_value = logging.DEBUG
+
+        adapter = IMAPlibLoggerAdapter(logger_mock, dict())
+        if six.PY3:
+            adapter.info("""> b'ICHH1 LOGIN [email protected] "secret"'""")
+            logger_mock._log.assert_called_once_with(
+                logging.INFO,
+                "> b'ICHH1 LOGIN **REDACTED**",
+                (),
+                extra={}
+            )
+        else:
+            adapter.info('> ICHH1 LOGIN [email protected] "secret"')
+            logger_mock.info.assert_called_once_with(
+                "> ICHH1 LOGIN **REDACTED**",
+                extra={}
+            )
+
 
 class TestTimeNormalisation(IMAPClientTest):