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The sunsetsha1 handler was moved to the data/ssl.py file. It was modi…
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…fied to be a passive data handler.
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yzninja committed Sep 15, 2015
1 parent 9b1f4d9 commit 8ee21f9
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66 changes: 66 additions & 0 deletions docs/gce/_update_dev.sh
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#!/bin/sh

set -e

# Directory paths used for nogotofail.
INSTALL_DIR=/opt/nogotofail
CONFIG_DIR=/etc/nogotofail
LOG_DIR=/var/log/nogotofail

# Stop the nogotofail-mitm and other associated services if they're running.
if (ps ax | grep -v grep | grep nogotofail-mitm > /dev/null) then
sudo /etc/init.d/nogotofail-mitm stop
fi
if (ps ax | grep -v grep | grep dnsmasq > /dev/null) then
sudo /etc/init.d/dnsmasq stop
fi
if (ps ax | grep -v grep | grep openvpn > /dev/null) then
sudo /etc/init.d/openvpn stop
fi
# Remove Python files and compiled versions i.e. *.py and *.pyc files.
# TODO: Find a more elegant method for uninstalling a Python program.
#rm -rf $INSTALL_DIR
#rm -rf $CONFIG_DIR
#rm -rf $LOG_DIR
find $INSTALL_DIR -type f -name '*.py' -delete
find $INSTALL_DIR -type f -name '*.pyc' -delete

# Install toolchain dependencies
sudo apt-get update
sudo apt-get -y upgrade
#sudo apt-get -y install patch make gcc libssl-dev python-openssl liblzo2-dev libpam-dev

# Install OpenVPN and dnsmasq
#sudo apt-get -y install openvpn dnsmasq

# Build and install a patched version of OpenVPN.
# This is needed because the OpenVPN 2.3.x still does not properly handle
# floating clients (those whose source IP address as seen by the server changes
# from time to time) which is a regular occurrence in the mobile world.
# OpenVPN 2.4 might ship with proper support out of the box. In that case, this
# kludge can be removed.
#./build_openvpn.sh

# Build and install a patched version of dnsmasq.
# This is needed because GCE does not support IPv6. We thus blackhole IPv6
# traffic from clients so that they are forced to use IPv4. However, default
# DNS servers will still resolve hostnames to IPv6 addresses causing clients to
# attempt IPv6. To avoid clients attempting IPv6, we run a patched dnsmasq DNS
# server which empties AAAA records thus causing clients to go for A records
# which provide IPv4 addresses.
#./build_dnsmasq.sh

# Set up OpenVPN server
#sudo ./setup_openvpn.sh

# Set up the MiTM daemons
sudo ./setup_mitm.sh

# Move dev mitm.conf file into /etc/nogotofail directory
sudo cp /home/michael/noseyp_setup/ngtf_mitm.conf /etc/nogotofail/mitm.conf

# Restart all the relevant daemons
sudo /etc/init.d/dnsmasq start
sudo /etc/init.d/openvpn start
#sudo /etc/init.d/nogotofail-mitm stop || true
sudo /etc/init.d/nogotofail-mitm start
2 changes: 1 addition & 1 deletion nogotofail/mitm/connection/handlers/connection/__init__.py
Original file line number Diff line number Diff line change
Expand Up @@ -26,4 +26,4 @@
from droptls import DropTLS
from ccs import EarlyCCS
from serverkeyreplace import ServerKeyReplacementMITM
from sunsetsha1 import SunsetSHA1
# from sunsetsha1 import SunsetSHA1
104 changes: 104 additions & 0 deletions nogotofail/mitm/connection/handlers/data/ssl.py
Original file line number Diff line number Diff line change
Expand Up @@ -19,7 +19,12 @@
from nogotofail.mitm.connection.handlers.data import DataHandler
from nogotofail.mitm.connection.handlers.store import handler
from nogotofail.mitm.event import connection
from nogotofail.mitm import util
from nogotofail.mitm.util import ssl2, tls, vuln
from nogotofail.mitm.util.tls.types import HandshakeMessage, TlsRecord
from datetime import datetime
import OpenSSL.crypto


@handler.passive(handlers)
class InsecureCipherDetectionHandler(DataHandler):
Expand Down Expand Up @@ -90,3 +95,102 @@ def on_ssl(self, client_hello):
self.log(logging.ERROR,
"Client enabled SSLv3 protocol without TLS_FALLBACK_SCSV")
self.log_attack_event(data="SSLv3")


@handler.passive(handlers)
class SunsetSHA1(DataHandler):
name = "sunsetsha1"
description = (
"Detects TLS certificates using the SHA-1 signature algorithm that "
"expire during of after the Google Chrome sunset period.")

buffer = ""
ssl = False

def on_ssl(self, client_hello):
self.ssl = True
return True

def on_response(self, response):
if not self.ssl:
return response
response = self.buffer + response
self.buffer = ""
CRT_DATE_FORMAT = "%Y%m%d%H%M%SZ"
try:
index = 0
while index < len(response):
record, size = TlsRecord.from_stream(response[index:])
for i, message in enumerate(record.messages):
# Check for Certificate message
if (isinstance(message, tls.types.HandshakeMessage) and
message.type == HandshakeMessage.TYPE.CERTIFICATE):
certificate = message.obj
if certificate.certificates:
# Check leaf certificate in chain for SHA-1 sunset issue
crt_byte_string = certificate.certificates[0]
a_certificate = OpenSSL.crypto.load_certificate(
OpenSSL.crypto.FILETYPE_ASN1, crt_byte_string)
crt_signature_algorithm = \
a_certificate.get_signature_algorithm()
if ("sha1" in crt_signature_algorithm):
crt_CN = str(a_certificate.get_subject().CN or "")
crt_not_before = str(a_certificate.get_notBefore() or "")
crt_not_after = str(a_certificate.get_notAfter() or "")
debug_message = \
["Certicate using SHA-1 with attributes - CN \"",
crt_CN, "\", notBefore \"", crt_not_before,
"\", notAfter \"", crt_not_after,
"\", signature_algorithm \"",
crt_signature_algorithm, "\""]
self.log(logging.DEBUG, "".join(debug_message))
crt_not_after = datetime.strptime(crt_not_after,
CRT_DATE_FORMAT)
self._alert_on_sunset_sha1(crt_not_after, crt_CN)
index += size
except ValueError:
# Failed to parse TLS, this is probably due to a short read of a TLS
# record. Buffer the response to try and get more data.
self.buffer = response
# But don't buffer too much, give up after 16k.
if len(self.buffer) > 2**14:
response = self.buffer
self.buffer = ""
return self.buffer
return ""
return response

def _alert_on_sunset_sha1(self, crt_not_after, crt_CN):
""" Raises an alert if a certificate signature algorithm uses SHA-1 and
it expires during or after the Google Chrome sunset period.
"""
# SHA-1 sunset dates based on Google Chrome dates published dates. See
# http://googleonlinesecurity.blogspot.com/2014/09/gradually-sunsetting-sha-1.html
sunset_critical_date = datetime.strptime("31-12-2016", "%d-%m-%Y")
sunset_error_date = datetime.strptime("30-06-2016", "%d-%m-%Y")
sunset_warning_date = datetime.strptime("31-12-2015", "%d-%m-%Y")

if (crt_not_after > sunset_critical_date):
log_message = \
["Certificate with CN ", crt_CN,
" uses SHA-1 and expires after 31 Dec 2016"]
self.log(logging.CRITICAL, "".join(log_message))
self.log_event(logging.CRITICAL, connection.AttackEvent(
self.connection, self.name, True, ""))
self.connection.vuln_notify(util.vuln.VULN_SUNSET_SHA1)
elif (crt_not_after > sunset_error_date):
log_message = \
["Certificate with CN ", crt_CN,
" uses SHA-1 and expires after 30 Jun 2016"]
self.log(logging.ERROR, "".join(log_message))
self.log_event(logging.ERROR, connection.AttackEvent(
self.connection, self.name, True, ""))
self.connection.vuln_notify(util.vuln.VULN_SUNSET_SHA1)
elif (crt_not_after > sunset_warning_date):
log_message = \
["Certificate with CN ", crt_CN,
" uses SHA-1 and expires after 31 Dec 2015"]
self.log(logging.WARNING, "".join(log_message))
self.log_event(logging.WARNING, connection.AttackEvent(
self.connection, self.name, True, ""))
self.connection.vuln_notify(util.vuln.VULN_SUNSET_SHA1)

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