def process_task(self, server_info: ServerConnectivityInfo,
scan_command: PluginScanCommand) -> 'EarlyDataScanResult':
if not isinstance(scan_command, EarlyDataScanCommand):
raise ValueError('Unexpected scan command')
session = None
is_early_data_supported = False
ssl_connection = server_info.get_preconfigured_ssl_connection(
override_ssl_version=OpenSslVersionEnum.TLSV1_3)
try:
# Perform an SSL handshake and keep the session
ssl_connection.connect()
# Send and receive data for the TLS session to be created
ssl_connection.ssl_client.write(
HttpRequestGenerator.get_request(host=server_info.hostname))
ssl_connection.ssl_client.read(2048)
session = ssl_connection.ssl_client.get_session()
except SslHandshakeRejected:
# TLS 1.3 not supported
is_early_data_supported = False
finally:
ssl_connection.close()
# Then try to re-use the session and send early data
if session is not None:
ssl_connection2 = server_info.get_preconfigured_ssl_connection(
override_ssl_version=OpenSslVersionEnum.TLSV1_3)
ssl_connection2.ssl_client.set_session(session)
try:
# Open a socket to the server but don't do the handshake
ssl_connection2.do_pre_handshake(None)
# Send one byte of early data
ssl_connection2.ssl_client.write_early_data(b'E')
ssl_connection2.ssl_client.do_handshake()
if ssl_connection2.ssl_client.get_early_data_status(
) == OpenSslEarlyDataStatusEnum.ACCEPTED:
is_early_data_supported = True
else:
is_early_data_supported = False
except OpenSSLError as e:
if 'function you should not call' in e.args[0]:
# This is what OpenSSL returns when the server did not enable early data
is_early_data_supported = False
else:
raise
finally:
ssl_connection2.close()
return EarlyDataScanResult(server_info, scan_command,
is_early_data_supported)
def process_task(
self,
server_info: ServerConnectivityInfo,
scan_command: PluginScanCommand
) -> 'EarlyDataScanResult':
if not isinstance(scan_command, EarlyDataScanCommand):
raise ValueError('Unexpected scan command')
session = None
is_early_data_supported = False
ssl_connection = server_info.get_preconfigured_ssl_connection(override_ssl_version=OpenSslVersionEnum.TLSV1_3)
try:
# Perform an SSL handshake and keep the session
ssl_connection.connect()
# Send and receive data for the TLS session to be created
ssl_connection.ssl_client.write(HttpRequestGenerator.get_request(host=server_info.hostname))
ssl_connection.ssl_client.read(2048)
session = ssl_connection.ssl_client.get_session()
except SslHandshakeRejected:
# TLS 1.3 not supported
is_early_data_supported = False
finally:
ssl_connection.close()
# Then try to re-use the session and send early data
if session is not None:
ssl_connection2 = server_info.get_preconfigured_ssl_connection(
override_ssl_version=OpenSslVersionEnum.TLSV1_3
)
ssl_connection2.ssl_client.set_session(session)
try:
# Open a socket to the server but don't do the handshake
ssl_connection2.do_pre_handshake(None)
# Send one byte of early data
ssl_connection2.ssl_client.write_early_data(b'E')
ssl_connection2.ssl_client.do_handshake()
if ssl_connection2.ssl_client.get_early_data_status() == OpenSslEarlyDataStatusEnum.ACCEPTED:
is_early_data_supported = True
else:
is_early_data_supported = False
except OpenSSLError as e:
if 'function you should not call' in e.args[0]:
# This is what OpenSSL returns when the server did not enable early data
is_early_data_supported = False
else:
raise
finally:
ssl_connection2.close()
return EarlyDataScanResult(server_info, scan_command, is_early_data_supported)
def _resume_ssl_session(
server_info: ServerConnectivityInfo,
ssl_session: Optional[nassl._nassl.SSL_SESSION] = None,
should_enable_tls_ticket: bool = False
) -> nassl._nassl.SSL_SESSION:
"""Connect to the server and returns the session object that was assigned for that connection.
If ssl_session is given, tries to resume that session.
"""
ssl_connection = server_info.get_preconfigured_ssl_connection()
if not should_enable_tls_ticket:
# Need to disable TLS tickets to test session IDs, according to rfc5077:
# If a ticket is presented by the client, the server MUST NOT attempt
# to use the Session ID in the ClientHello for stateful session resumption
ssl_connection.ssl_client.disable_stateless_session_resumption(
) # Turning off TLS tickets.
if ssl_session:
ssl_connection.ssl_client.set_session(ssl_session)
try:
# Perform the SSL handshake
ssl_connection.connect()
new_session = ssl_connection.ssl_client.get_session(
) # Get session data
finally:
ssl_connection.close()
return new_session
def process_task(
self,
server_info: ServerConnectivityInfo,
scan_command: plugin_base.PluginScanCommand
) -> 'OpenSslCcsInjectionScanResult':
if not isinstance(scan_command, OpenSslCcsInjectionScanCommand):
raise ValueError('Unexpected scan command')
if server_info.highest_ssl_version_supported >= OpenSslVersionEnum.TLSV1_3:
# The server uses a recent version of OpenSSL and it cannot be vulnerable to CCS Injection
return OpenSslCcsInjectionScanResult(server_info, scan_command, False)
ssl_connection = server_info.get_preconfigured_ssl_connection()
# Replace nassl.sslClient.do_handshake() with a CCS checking SSL handshake so that all the SSLyze options
# (startTLS, proxy, etc.) still work
ssl_connection.ssl_client.do_handshake = types.MethodType(do_handshake_with_ccs_injection,
ssl_connection.ssl_client)
is_vulnerable = False
try:
# Start the SSL handshake
ssl_connection.connect()
except VulnerableToCcsInjection:
# The test was completed and the server is vulnerable
is_vulnerable = True
except NotVulnerableToCcsInjection:
# The test was completed and the server is NOT vulnerable
pass
finally:
ssl_connection.close()
return OpenSslCcsInjectionScanResult(server_info, scan_command, is_vulnerable)
def process_task(
self, server_info: ServerConnectivityInfo,
scan_command: PluginScanCommand) -> 'HeartbleedScanResult':
if not isinstance(scan_command, HeartbleedScanCommand):
raise ValueError('Unexpected scan command')
ssl_connection = server_info.get_preconfigured_ssl_connection()
# Replace nassl.sslClient.do_handshake() with a heartbleed checking SSL handshake so that all the SSLyze options
# (startTLS, proxy, etc.) still work
ssl_connection.ssl_client.do_handshake = types.MethodType(
do_handshake_with_heartbleed, ssl_connection.ssl_client)
is_vulnerable_to_heartbleed = False
try:
# Start the SSL handshake
ssl_connection.connect()
except VulnerableToHeartbleed:
# The test was completed and the server is vulnerable
is_vulnerable_to_heartbleed = True
except NotVulnerableToHeartbleed:
# The test was completed and the server is NOT vulnerable
pass
finally:
ssl_connection.close()
return HeartbleedScanResult(server_info, scan_command,
is_vulnerable_to_heartbleed)
def _get_selected_cipher_suite(
server_connectivity: ServerConnectivityInfo,
ssl_version: OpenSslVersionEnum,
openssl_cipher_str: str,
should_use_legacy_openssl: Optional[bool],
) -> "AcceptedCipherSuite":
"""Given an OpenSSL cipher string (which may specify multiple cipher suites), return the cipher suite that was
selected by the server during the SSL handshake.
"""
ssl_connection = server_connectivity.get_preconfigured_ssl_connection(
override_ssl_version=ssl_version,
should_use_legacy_openssl=should_use_legacy_openssl)
ssl_connection.ssl_client.set_cipher_list(openssl_cipher_str)
# Perform the SSL handshake
try:
ssl_connection.connect()
selected_cipher = AcceptedCipherSuite.from_ongoing_ssl_connection(
ssl_connection, ssl_version)
except ClientCertificateRequested:
selected_cipher = AcceptedCipherSuite.from_ongoing_ssl_connection(
ssl_connection, ssl_version)
finally:
ssl_connection.close()
return selected_cipher
def _get_rsa_parameters(
server_info: ServerConnectivityInfo,
openssl_cipher_string: str
) -> Optional[Tuple[int, int]]:
ssl_connection = server_info.get_preconfigured_ssl_connection()
ssl_connection.ssl_client.set_cipher_list(openssl_cipher_string)
parsed_cert = None
try:
# Perform the SSL handshake
ssl_connection.connect()
certificate = ssl_connection.ssl_client.get_peer_certificate()
parsed_cert = load_pem_x509_certificate(certificate.as_pem().encode('ascii'), backend=default_backend())
except SslHandshakeRejected:
# Server does not support RSA cipher suites?
pass
except ClientCertificateRequested:
# AD: The server asked for a client cert. We could still retrieve the server certificate, but it is unclear
# to me if the ROBOT check is supposed to work even if we do not provide a client cert. My guess is that
# it should not work since it requires completing a full handshake, which we can't without a client cert.
# Hence, propagate the error to make the check fail.
raise
finally:
ssl_connection.close()
if parsed_cert:
return parsed_cert.public_key().public_numbers().n, parsed_cert.public_key().public_numbers().e
else:
return None
def _get_and_verify_certificate_chain(
server_info: ServerConnectivityInfo,
trust_store: TrustStore
) -> Tuple[List[Certificate], str, Optional[OcspResponse]]:
"""Connects to the target server and uses the supplied trust store to validate the server's certificate.
Returns the server's certificate and OCSP response.
"""
ssl_connection = server_info.get_preconfigured_ssl_connection(ssl_verify_locations=trust_store.path)
# Enable OCSP stapling
ssl_connection.ssl_client.set_tlsext_status_ocsp()
try: # Perform the SSL handshake
ssl_connection.connect()
ocsp_response = ssl_connection.ssl_client.get_tlsext_status_ocsp_resp()
x509_cert_chain = ssl_connection.ssl_client.get_peer_cert_chain()
(_, verify_str) = ssl_connection.ssl_client.get_certificate_chain_verify_result()
except ClientCertificateRequested: # The server asked for a client cert
# We can get the server cert anyway
ocsp_response = ssl_connection.ssl_client.get_tlsext_status_ocsp_resp()
x509_cert_chain = ssl_connection.ssl_client.get_peer_cert_chain()
(_, verify_str) = ssl_connection.ssl_client.get_certificate_chain_verify_result()
finally:
ssl_connection.close()
# Parse the certificates using the cryptography module
parsed_x509_chain = [load_pem_x509_certificate(x509_cert.as_pem().encode('ascii'), backend=default_backend())
for x509_cert in x509_cert_chain]
return parsed_x509_chain, verify_str, ocsp_response
def _resume_ssl_session(
server_info: ServerConnectivityInfo,
ssl_version_to_use: OpenSslVersionEnum,
ssl_session: Optional[nassl._nassl.SSL_SESSION] = None,
should_enable_tls_ticket: bool = False
) -> nassl._nassl.SSL_SESSION:
"""Connect to the server and returns the session object that was assigned for that connection.
If ssl_session is given, tries to resume that session.
"""
ssl_connection = server_info.get_preconfigured_ssl_connection(override_ssl_version=ssl_version_to_use)
if not should_enable_tls_ticket:
# Need to disable TLS tickets to test session IDs, according to rfc5077:
# If a ticket is presented by the client, the server MUST NOT attempt
# to use the Session ID in the ClientHello for stateful session resumption
ssl_connection.ssl_client.disable_stateless_session_resumption() # Turning off TLS tickets.
if ssl_session:
ssl_connection.ssl_client.set_session(ssl_session)
try:
# Perform the SSL handshake
ssl_connection.connect()
new_session = ssl_connection.ssl_client.get_session() # Get session data
finally:
ssl_connection.close()
return new_session
def process_task(
self,
server_info: ServerConnectivityInfo,
scan_command: PluginScanCommand
) -> 'CompressionScanResult':
if not isinstance(scan_command, CompressionScanCommand):
raise ValueError('Unexpected scan command')
ssl_connection = server_info.get_preconfigured_ssl_connection(should_use_legacy_openssl=True)
# Make sure OpenSSL was built with support for compression to avoid false negatives
if 'zlib compression' not in ssl_connection.ssl_client.get_available_compression_methods():
raise RuntimeError('OpenSSL was not built with support for zlib / compression. '
'Did you build nassl yourself ?')
try:
# Perform the SSL handshake
ssl_connection.connect()
compression_name = ssl_connection.ssl_client.get_current_compression_method()
except ClientCertificateRequested:
# The server asked for a client cert
compression_name = ssl_connection.ssl_client.get_current_compression_method()
finally:
ssl_connection.close()
return CompressionScanResult(server_info, scan_command, compression_name)
def process_task(
self, server_info: ServerConnectivityInfo,
scan_command: plugin_base.PluginScanCommand
) -> "OpenSslCcsInjectionScanResult":
if not isinstance(scan_command, OpenSslCcsInjectionScanCommand):
raise ValueError("Unexpected scan command")
if server_info.highest_ssl_version_supported >= OpenSslVersionEnum.TLSV1_3:
# The server uses a recent version of OpenSSL and it cannot be vulnerable to CCS Injection
return OpenSslCcsInjectionScanResult(server_info, scan_command,
False)
ssl_connection = server_info.get_preconfigured_ssl_connection()
# Replace nassl.sslClient.do_handshake() with a CCS checking SSL handshake so that all the SSLyze options
# (startTLS, proxy, etc.) still work
ssl_connection.ssl_client.do_handshake = types.MethodType(
do_handshake_with_ccs_injection, ssl_connection.ssl_client)
is_vulnerable = False
try:
# Start the SSL handshake
ssl_connection.connect()
except VulnerableToCcsInjection:
# The test was completed and the server is vulnerable
is_vulnerable = True
except NotVulnerableToCcsInjection:
# The test was completed and the server is NOT vulnerable
pass
finally:
ssl_connection.close()
return OpenSslCcsInjectionScanResult(server_info, scan_command,
is_vulnerable)
def process_task(
self, server_info: ServerConnectivityInfo,
scan_command: PluginScanCommand) -> 'CompressionScanResult':
if not isinstance(scan_command, CompressionScanCommand):
raise ValueError('Unexpected scan command')
ssl_connection = server_info.get_preconfigured_ssl_connection(
should_use_legacy_openssl=True)
# Make sure OpenSSL was built with support for compression to avoid false negatives
if 'zlib compression' not in ssl_connection.ssl_client.get_available_compression_methods(
):
raise RuntimeError(
'OpenSSL was not built with support for zlib / compression. '
'Did you build nassl yourself ?')
try:
# Perform the SSL handshake
ssl_connection.connect()
compression_name = ssl_connection.ssl_client.get_current_compression_method(
)
except ClientCertificateRequested:
# The server asked for a client cert
compression_name = ssl_connection.ssl_client.get_current_compression_method(
)
finally:
ssl_connection.close()
return CompressionScanResult(server_info, scan_command,
compression_name)
def process_task(
self,
server_info: ServerConnectivityInfo,
scan_command: PluginScanCommand
) -> 'HeartbleedScanResult':
if not isinstance(scan_command, HeartbleedScanCommand):
raise ValueError('Unexpected scan command')
ssl_connection = server_info.get_preconfigured_ssl_connection()
# Replace nassl.sslClient.do_handshake() with a heartbleed checking SSL handshake so that all the SSLyze options
# (startTLS, proxy, etc.) still work
ssl_connection.ssl_client.do_handshake = types.MethodType(do_handshake_with_heartbleed,
ssl_connection.ssl_client)
is_vulnerable_to_heartbleed = False
try:
# Start the SSL handshake
ssl_connection.connect()
except VulnerableToHeartbleed:
# The test was completed and the server is vulnerable
is_vulnerable_to_heartbleed = True
except NotVulnerableToHeartbleed:
# The test was completed and the server is NOT vulnerable
pass
finally:
ssl_connection.close()
return HeartbleedScanResult(server_info, scan_command, is_vulnerable_to_heartbleed)
def _get_and_verify_certificate_chain(
server_info: ServerConnectivityInfo,
trust_store: TrustStore
) -> Tuple[List[Certificate], str, Optional[OcspResponse]]:
"""Connects to the target server and uses the supplied trust store to validate the server's certificate.
Returns the server's certificate and OCSP response.
"""
ssl_connection = server_info.get_preconfigured_ssl_connection(ssl_verify_locations=trust_store.path)
# Enable OCSP stapling
ssl_connection.ssl_client.set_tlsext_status_ocsp()
try: # Perform the SSL handshake
ssl_connection.connect()
ocsp_response = ssl_connection.ssl_client.get_tlsext_status_ocsp_resp()
x509_cert_chain = ssl_connection.ssl_client.get_peer_cert_chain()
(_, verify_str) = ssl_connection.ssl_client.get_certificate_chain_verify_result()
except ClientCertificateRequested: # The server asked for a client cert
# We can get the server cert anyway
ocsp_response = ssl_connection.ssl_client.get_tlsext_status_ocsp_resp()
x509_cert_chain = ssl_connection.ssl_client.get_peer_cert_chain()
(_, verify_str) = ssl_connection.ssl_client.get_certificate_chain_verify_result()
finally:
ssl_connection.close()
# Parse the certificates using the cryptography module
parsed_x509_chain = [load_pem_x509_certificate(x509_cert.as_pem().encode('ascii'), backend=default_backend())
for x509_cert in x509_cert_chain]
return parsed_x509_chain, verify_str, ocsp_response
def _get_rsa_parameters(
server_info: ServerConnectivityInfo,
openssl_cipher_string: str) -> Optional[Tuple[int, int]]:
ssl_connection = server_info.get_preconfigured_ssl_connection()
ssl_connection.ssl_client.set_cipher_list(openssl_cipher_string)
parsed_cert = None
try:
# Perform the SSL handshake
ssl_connection.connect()
certificate = ssl_connection.ssl_client.get_peer_certificate()
parsed_cert = load_pem_x509_certificate(
certificate.as_pem().encode('ascii'),
backend=default_backend())
except SslHandshakeRejected:
# Server does not support RSA cipher suites?
pass
except ClientCertificateRequested:
# AD: The server asked for a client cert. We could still retrieve the server certificate, but it is unclear
# to me if the ROBOT check is supposed to work even if we do not provide a client cert. My guess is that
# it should not work since it requires completing a full handshake, which we can't without a client cert.
# Hence, propagate the error to make the check fail.
raise
finally:
ssl_connection.close()
if parsed_cert:
try:
return parsed_cert.public_key().public_numbers(
).n, parsed_cert.public_key().public_numbers().e
except AttributeError:
return None
else:
return None
def process_task(
self,
server_info: ServerConnectivityInfo,
scan_command: PluginScanCommand
) -> 'HttpHeadersScanResult':
if not isinstance(scan_command, HttpHeadersScanCommand):
raise ValueError('Unexpected scan command')
if server_info.tls_wrapped_protocol not in [TlsWrappedProtocolEnum.PLAIN_TLS, TlsWrappedProtocolEnum.HTTPS]:
raise ValueError('Cannot test for HTTP headers on a StartTLS connection.')
# Perform the SSL handshake
mozilla_store = TrustStoresRepository.get_default().get_main_store()
ssl_connection = server_info.get_preconfigured_ssl_connection(ssl_verify_locations=mozilla_store.path)
try:
ssl_connection.connect()
try:
verified_chain_as_pem = ssl_connection.ssl_client.get_verified_chain()
except CouldNotBuildVerifiedChain:
verified_chain_as_pem = None
# Send an HTTP GET request to the server
ssl_connection.ssl_client.write(HttpRequestGenerator.get_request(host=server_info.hostname))
# We do not follow redirections because the security headers must be set on the first page according to
# https://hstspreload.appspot.com/:
# "If you are serving an additional redirect from your HTTPS site, that redirect must still have the HSTS
# header (rather than the page it redirects to)."
http_response = HttpResponseParser.parse_from_ssl_connection(ssl_connection.ssl_client)
finally:
ssl_connection.close()
if http_response.version == 9:
# HTTP 0.9 => Probably not an HTTP response
raise ValueError('Server did not return an HTTP response')
# Parse the certificate chain
verified_chain = [
load_pem_x509_certificate(cert_as_pem.encode('ascii'), backend=default_backend())
for cert_as_pem in verified_chain_as_pem
] if verified_chain_as_pem else None
# Parse each header
hsts_header = StrictTransportSecurityHeader.from_http_response(http_response)
expect_ct_header = ExpectCtHeader.from_http_response(http_response)
hpkp_header = PublicKeyPinsHeader.from_http_response(http_response)
hpkp_report_only_header = PublicKeyPinsReportOnlyHeader.from_http_response(http_response)
return HttpHeadersScanResult(
server_info,
scan_command,
hsts_header,
hpkp_header,
hpkp_report_only_header,
expect_ct_header,
verified_chain
)
def _test_client_renegotiation(server_info: ServerConnectivityInfo, ssl_version_to_use: OpenSslVersionEnum) -> bool:
"""Check whether the server honors session renegotiation requests.
"""
ssl_connection = server_info.get_preconfigured_ssl_connection(
override_ssl_version=ssl_version_to_use, should_use_legacy_openssl=True
)
try:
# Perform the SSL handshake
ssl_connection.connect()
try:
# Let's try to renegotiate
ssl_connection.ssl_client.do_renegotiate()
accepts_client_renegotiation = True
# Errors caused by a server rejecting the renegotiation
except socket.timeout:
# This is how Netty rejects a renegotiation - https://github.com/nabla-c0d3/sslyze/issues/114
accepts_client_renegotiation = False
except socket.error as e:
if 'connection was forcibly closed' in str(e.args):
accepts_client_renegotiation = False
elif 'reset by peer' in str(e.args):
accepts_client_renegotiation = False
elif 'Nassl SSL handshake failed' in str(e.args):
accepts_client_renegotiation = False
else:
raise
except OpenSSLError as e:
if 'handshake failure' in str(e.args):
accepts_client_renegotiation = False
elif 'no renegotiation' in str(e.args):
accepts_client_renegotiation = False
elif 'tlsv1 unrecognized name' in str(e.args):
# Yahoo's very own way of rejecting a renegotiation
accepts_client_renegotiation = False
elif 'tlsv1 alert internal error' in str(e.args):
# Jetty server: https://github.com/nabla-c0d3/sslyze/issues/290
accepts_client_renegotiation = False
else:
raise
except ConnectionError:
accepts_client_renegotiation = False
finally:
ssl_connection.close()
return accepts_client_renegotiation
def _test_secure_renegotiation(server_info: ServerConnectivityInfo) -> bool:
"""Check whether the server supports secure renegotiation.
"""
ssl_connection = server_info.get_preconfigured_ssl_connection(should_use_legacy_openssl=True)
try:
# Perform the SSL handshake
ssl_connection.connect()
supports_secure_renegotiation = ssl_connection.ssl_client.get_secure_renegotiation_support()
finally:
ssl_connection.close()
return supports_secure_renegotiation
def _test_client_renegotiation(server_info: ServerConnectivityInfo, ssl_version_to_use: OpenSslVersionEnum) -> bool:
"""Check whether the server honors session renegotiation requests.
"""
ssl_connection = server_info.get_preconfigured_ssl_connection(
override_ssl_version=ssl_version_to_use, should_use_legacy_openssl=True
)
try:
# Perform the SSL handshake
ssl_connection.connect()
try:
# Let's try to renegotiate
ssl_connection.ssl_client.do_renegotiate()
accepts_client_renegotiation = True
# Errors caused by a server rejecting the renegotiation
except socket.timeout:
# This is how Netty rejects a renegotiation - https://github.com/nabla-c0d3/sslyze/issues/114
accepts_client_renegotiation = False
except socket.error as e:
if 'connection was forcibly closed' in str(e.args):
accepts_client_renegotiation = False
elif 'reset by peer' in str(e.args):
accepts_client_renegotiation = False
elif 'Nassl SSL handshake failed' in str(e.args):
accepts_client_renegotiation = False
else:
raise
except OpenSSLError as e:
if 'handshake failure' in str(e.args):
accepts_client_renegotiation = False
elif 'no renegotiation' in str(e.args):
accepts_client_renegotiation = False
elif 'tlsv1 unrecognized name' in str(e.args):
# Yahoo's very own way of rejecting a renegotiation
accepts_client_renegotiation = False
elif 'tlsv1 alert internal error' in str(e.args):
# Jetty server: https://github.com/nabla-c0d3/sslyze/issues/290
accepts_client_renegotiation = False
else:
raise
except ConnectionError:
accepts_client_renegotiation = False
finally:
ssl_connection.close()
return accepts_client_renegotiation
def _test_secure_renegotiation(server_info: ServerConnectivityInfo, ssl_version_to_use: OpenSslVersionEnum) -> bool:
"""Check whether the server supports secure renegotiation.
"""
ssl_connection = server_info.get_preconfigured_ssl_connection(
override_ssl_version=ssl_version_to_use, should_use_legacy_openssl=True
)
try:
# Perform the SSL handshake
ssl_connection.connect()
supports_secure_renegotiation = ssl_connection.ssl_client.get_secure_renegotiation_support()
finally:
ssl_connection.close()
return supports_secure_renegotiation
def process_task(
self, server_info: ServerConnectivityInfo,
scan_command: PluginScanCommand) -> "FallbackScsvScanResult":
if not isinstance(scan_command, FallbackScsvScanCommand):
raise ValueError("Unexpected scan command")
if server_info.highest_ssl_version_supported.value <= OpenSslVersionEnum.SSLV3.value:
raise ValueError(
"Server only supports SSLv3; no downgrade attacks are possible"
)
# Try with TLS 1.2 even if the server supports TLS 1.3 or higher as there is no downgrade possible with TLS 1.3
if server_info.highest_ssl_version_supported >= OpenSslVersionEnum.TLSV1_3:
ssl_version_to_use = OpenSslVersionEnum.TLSV1_2
else:
ssl_version_to_use = server_info.highest_ssl_version_supported
# Try to connect using a lower TLS version with the fallback cipher suite enabled
ssl_version_downgrade = OpenSslVersionEnum(ssl_version_to_use.value -
1) # type: ignore
ssl_connection = server_info.get_preconfigured_ssl_connection(
override_ssl_version=ssl_version_downgrade)
ssl_connection.ssl_client.enable_fallback_scsv()
supports_fallback_scsv = False
try:
# Perform the SSL handshake
ssl_connection.connect()
except _nassl.OpenSSLError as e:
# This is the right, specific alert the server should return
if "tlsv1 alert inappropriate fallback" in str(e.args):
supports_fallback_scsv = True
else:
raise
except SslHandshakeRejected:
# If the handshake is rejected, we assume downgrade attacks are prevented (this is how F5 balancers do it)
# although it could also be because the server does not support this version of TLS
# https://github.com/nabla-c0d3/sslyze/issues/119
supports_fallback_scsv = True
finally:
ssl_connection.close()
return FallbackScsvScanResult(server_info, scan_command,
supports_fallback_scsv)
def _get_and_verify_certificate_chain(
server_info: ServerConnectivityInfo,
trust_store: TrustStore
) -> Tuple[List[str], Optional[List[str]], str, Optional[OcspResponse]]:
"""Connect to the target server and uses the supplied trust store to validate the server's certificate.
"""
ssl_connection = server_info.get_preconfigured_ssl_connection(ssl_verify_locations=trust_store.path)
# Enable OCSP stapling
ssl_connection.ssl_client.set_tlsext_status_ocsp()
try: # Perform the SSL handshake
ssl_connection.connect()
ocsp_response = ssl_connection.ssl_client.get_tlsext_status_ocsp_resp()
received_chain_as_pem = ssl_connection.ssl_client.get_received_chain()
try:
verified_chain_as_pem = ssl_connection.ssl_client.get_verified_chain()
except CouldNotBuildVerifiedChain:
verified_chain_as_pem = None
except AttributeError:
# Only the modern SSL Client can build the verified chain; hence we get here if the server only supports
# an older version of TLS (pre 1.2)
verified_chain_as_pem = None
(_, verify_str) = ssl_connection.ssl_client.get_certificate_chain_verify_result()
except ClientCertificateRequested: # The server asked for a client cert
# We can get the server cert anyway
ocsp_response = ssl_connection.ssl_client.get_tlsext_status_ocsp_resp()
received_chain_as_pem = ssl_connection.ssl_client.get_received_chain()
try:
verified_chain_as_pem = ssl_connection.ssl_client.get_verified_chain()
except CouldNotBuildVerifiedChain:
verified_chain_as_pem = None
except AttributeError:
# Only the modern SSL Client can build the verified chain; hence we get here if the server only supports
# an older version of TLS (pre 1.2)
verified_chain_as_pem = None
(_, verify_str) = ssl_connection.ssl_client.get_certificate_chain_verify_result()
finally:
ssl_connection.close()
return received_chain_as_pem, verified_chain_as_pem, verify_str, ocsp_response
def process_task(
self,
server_info: ServerConnectivityInfo,
scan_command: PluginScanCommand
) -> 'FallbackScsvScanResult':
if not isinstance(scan_command, FallbackScsvScanCommand):
raise ValueError('Unexpected scan command')
if server_info.highest_ssl_version_supported.value <= OpenSslVersionEnum.SSLV3.value:
raise ValueError('Server only supports SSLv3; no downgrade attacks are possible')
# Try with TLS 1.2 even if the server supports TLS 1.3 or higher as there is no downgrade possible with TLS 1.3
if server_info.highest_ssl_version_supported >= OpenSslVersionEnum.TLSV1_3:
ssl_version_to_use = OpenSslVersionEnum.TLSV1_2
else:
ssl_version_to_use = server_info.highest_ssl_version_supported
# Try to connect using a lower TLS version with the fallback cipher suite enabled
ssl_version_downgrade = OpenSslVersionEnum(ssl_version_to_use.value - 1) # type: ignore
ssl_connection = server_info.get_preconfigured_ssl_connection(override_ssl_version=ssl_version_downgrade)
ssl_connection.ssl_client.enable_fallback_scsv()
supports_fallback_scsv = False
try:
# Perform the SSL handshake
ssl_connection.connect()
except _nassl.OpenSSLError as e:
# This is the right, specific alert the server should return
if 'tlsv1 alert inappropriate fallback' in str(e.args):
supports_fallback_scsv = True
else:
raise
except SslHandshakeRejected:
# If the handshake is rejected, we assume downgrade attacks are prevented (this is how F5 balancers do it)
# although it could also be because the server does not support this version of TLS
# https://github.com/nabla-c0d3/sslyze/issues/119
supports_fallback_scsv = True
finally:
ssl_connection.close()
return FallbackScsvScanResult(server_info, scan_command, supports_fallback_scsv)
def _send_robot_payload(
server_info: ServerConnectivityInfo,
ssl_version_to_use: OpenSslVersionEnum,
rsa_cipher_string: str,
robot_payload_enum: RobotPmsPaddingPayloadEnum,
robot_should_finish_handshake: bool,
rsa_modulus: int,
rsa_exponent: int,
) -> Tuple[RobotPmsPaddingPayloadEnum, str]:
# Do a handshake which each record and keep track of what the server returned
ssl_connection = server_info.get_preconfigured_ssl_connection(
override_ssl_version=ssl_version_to_use)
# Replace nassl.sslClient.do_handshake() with a ROBOT checking SSL handshake so that all the SSLyze
# options (startTLS, proxy, etc.) still work
ssl_connection.ssl_client.do_handshake = types.MethodType(
do_handshake_with_robot, ssl_connection.ssl_client)
ssl_connection.ssl_client.set_cipher_list(rsa_cipher_string)
# Compute the payload
cke_payload = RobotTlsRecordPayloads.get_client_key_exchange_record(
robot_payload_enum, TlsVersionEnum[ssl_version_to_use.name],
rsa_modulus, rsa_exponent)
# H4ck: we need to pass some arguments to the handshake but there is no simple way to do it; we use an attribute
ssl_connection.ssl_client._robot_cke_record = cke_payload
ssl_connection.ssl_client._robot_should_finish_handshake = robot_should_finish_handshake
server_response = ""
try:
# Start the SSL handshake
ssl_connection.connect()
except ServerResponseToRobot as e:
# Should always be thrown
server_response = e.server_response
except socket.timeout:
# https://github.com/nabla-c0d3/sslyze/issues/361
server_response = "Connection timed out"
finally:
ssl_connection.close()
return robot_payload_enum, server_response
def _get_security_headers(
cls, server_info: ServerConnectivityInfo
) -> Tuple[Optional[str], Optional[str], Optional[str], bool,
List[Certificate]]:
hpkp_report_only = False
# Perform the SSL handshake
ssl_connection = server_info.get_preconfigured_ssl_connection()
try:
ssl_connection.connect()
certificate_chain = [
load_pem_x509_certificate(x509_cert.as_pem().encode('ascii'),
backend=default_backend()) for
x509_cert in ssl_connection.ssl_client.get_peer_cert_chain()
]
# Send an HTTP GET request to the server
ssl_connection.ssl_client.write(
HttpRequestGenerator.get_request(host=server_info.hostname))
http_resp = HttpResponseParser.parse_from_ssl_connection(
ssl_connection.ssl_client)
finally:
ssl_connection.close()
if http_resp.version == 9:
# HTTP 0.9 => Probably not an HTTP response
raise ValueError('Server did not return an HTTP response')
else:
hsts_header = http_resp.getheader('strict-transport-security',
None)
hpkp_header = http_resp.getheader('public-key-pins', None)
expect_ct_header = http_resp.getheader('expect-ct', None)
if hpkp_header is None:
hpkp_report_only = True
hpkp_header = http_resp.getheader(
'public-key-pins-report-only', None)
# We do not follow redirections because the security headers must be set on the first page according to
# https://hstspreload.appspot.com/:
# "If you are serving an additional redirect from your HTTPS site, that redirect must still have the HSTS
# header (rather than the page it redirects to)."
return hsts_header, hpkp_header, expect_ct_header, hpkp_report_only, certificate_chain
def process_task(
self,
server_info: ServerConnectivityInfo,
scan_command: PluginScanCommand
) -> 'CompressionScanResult':
if not isinstance(scan_command, CompressionScanCommand):
raise ValueError('Unexpected scan command')
# Try with TLS 1.2 even if the server supports TLS 1.3 or higher as there is no compression with TLS 1.3
if server_info.highest_ssl_version_supported >= OpenSslVersionEnum.TLSV1_3:
ssl_version_to_use = OpenSslVersionEnum.TLSV1_2
else:
ssl_version_to_use = server_info.highest_ssl_version_supported
ssl_connection = server_info.get_preconfigured_ssl_connection(
override_ssl_version=ssl_version_to_use, should_use_legacy_openssl=True
)
# Make sure OpenSSL was built with support for compression to avoid false negatives
if 'zlib compression' not in ssl_connection.ssl_client.get_available_compression_methods():
raise RuntimeError(
'OpenSSL was not built with support for zlib / compression. Did you build nassl yourself ?'
)
try:
# Perform the SSL handshake
ssl_connection.connect()
compression_name = ssl_connection.ssl_client.get_current_compression_method()
except ClientCertificateRequested:
# The server asked for a client cert
compression_name = ssl_connection.ssl_client.get_current_compression_method()
except SslHandshakeRejected:
# Should only happen when the server only supports TLS 1.3, which does not support compression
compression_name = ''
finally:
ssl_connection.close()
return CompressionScanResult(server_info, scan_command, compression_name)
def _get_selected_cipher_suite(
server_connectivity: ServerConnectivityInfo,
ssl_version: OpenSslVersionEnum,
openssl_cipher_str: str,
should_use_legacy_openssl: Optional[bool]
) -> 'AcceptedCipherSuite':
"""Given an OpenSSL cipher string (which may specify multiple cipher suites), return the cipher suite that was
selected by the server during the SSL handshake.
"""
ssl_connection = server_connectivity.get_preconfigured_ssl_connection(
override_ssl_version=ssl_version, should_use_legacy_openssl=should_use_legacy_openssl
)
ssl_connection.ssl_client.set_cipher_list(openssl_cipher_str)
# Perform the SSL handshake
try:
ssl_connection.connect()
selected_cipher = AcceptedCipherSuite.from_ongoing_ssl_connection(ssl_connection, ssl_version)
except ClientCertificateRequested:
selected_cipher = AcceptedCipherSuite.from_ongoing_ssl_connection(ssl_connection, ssl_version)
finally:
ssl_connection.close()
return selected_cipher
def _send_robot_payload(
server_info: ServerConnectivityInfo,
rsa_cipher_string: str,
robot_payload_enum: RobotPmsPaddingPayloadEnum,
robot_should_finish_handshake: bool,
rsa_modulus: int,
rsa_exponent: int,
) -> Tuple[RobotPmsPaddingPayloadEnum, str]:
# Do a handshake which each record and keep track of what the server returned
ssl_connection = server_info.get_preconfigured_ssl_connection()
# Replace nassl.sslClient.do_handshake() with a ROBOT checking SSL handshake so that all the SSLyze
# options (startTLS, proxy, etc.) still work
ssl_connection.ssl_client.do_handshake = types.MethodType(do_handshake_with_robot,
ssl_connection.ssl_client)
ssl_connection.ssl_client.set_cipher_list(rsa_cipher_string)
# Compute the payload
cke_payload = RobotTlsRecordPayloads.get_client_key_exchange_record(
robot_payload_enum, server_info.highest_ssl_version_supported, rsa_modulus, rsa_exponent
)
# H4ck: we need to pass some arguments to the handshake but there is no simple way to do it; we use an attribute
ssl_connection.ssl_client._robot_cke_record = cke_payload
ssl_connection.ssl_client._robot_should_finish_handshake = robot_should_finish_handshake
server_response = ''
try:
# Start the SSL handshake
ssl_connection.connect()
except ServerResponseToRobot as e:
# Should always be thrown
server_response = e.server_response
finally:
ssl_connection.close()
return robot_payload_enum, server_response
def _get_security_headers(
cls,
server_info: ServerConnectivityInfo
) -> Tuple[Optional[str], Optional[str], Optional[str], bool, List[Certificate]]:
hpkp_report_only = False
# Perform the SSL handshake
ssl_connection = server_info.get_preconfigured_ssl_connection()
try:
ssl_connection.connect()
certificate_chain = [
load_pem_x509_certificate(x509_cert.as_pem().encode('ascii'), backend=default_backend())
for x509_cert in ssl_connection.ssl_client.get_peer_cert_chain()
]
# Send an HTTP GET request to the server
ssl_connection.ssl_client.write(HttpRequestGenerator.get_request(host=server_info.hostname))
http_resp = HttpResponseParser.parse_from_ssl_connection(ssl_connection.ssl_client)
finally:
ssl_connection.close()
if http_resp.version == 9:
# HTTP 0.9 => Probably not an HTTP response
raise ValueError('Server did not return an HTTP response')
else:
hsts_header = http_resp.getheader('strict-transport-security', None)
hpkp_header = http_resp.getheader('public-key-pins', None)
expect_ct_header = http_resp.getheader('expect-ct', None)
if hpkp_header is None:
hpkp_report_only = True
hpkp_header = http_resp.getheader('public-key-pins-report-only', None)
# We do not follow redirections because the security headers must be set on the first page according to
# https://hstspreload.appspot.com/:
# "If you are serving an additional redirect from your HTTPS site, that redirect must still have the HSTS
# header (rather than the page it redirects to)."
return hsts_header, hpkp_header, expect_ct_header, hpkp_report_only, certificate_chain
def _test_cipher_suite(server_connectivity_info: ServerConnectivityInfo,
ssl_version: OpenSslVersionEnum,
openssl_cipher_name: str) -> 'CipherSuite':
"""Initiates a SSL handshake with the server using the SSL version and the cipher suite specified.
"""
requires_legacy_openssl = True
if ssl_version == OpenSslVersionEnum.TLSV1_2:
# For TLS 1.2, we need to pick the right version of OpenSSL depending on which cipher suite
requires_legacy_openssl = WorkaroundForTls12ForCipherSuites.requires_legacy_openssl(
openssl_cipher_name)
elif ssl_version == OpenSslVersionEnum.TLSV1_3:
requires_legacy_openssl = False
ssl_connection = server_connectivity_info.get_preconfigured_ssl_connection(
override_ssl_version=ssl_version,
should_use_legacy_openssl=requires_legacy_openssl)
# Only enable the cipher suite to test; not trivial anymore since OpenSSL 1.1.1 and TLS 1.3
if ssl_version == OpenSslVersionEnum.TLSV1_3:
# The function to control cipher suites is different for TLS 1.3
# Disable the default, non-TLS 1.3 cipher suites
ssl_connection.ssl_client.set_cipher_list('')
# Enable the one TLS 1.3 cipher suite we want to test
ssl_connection.ssl_client.set_ciphersuites(openssl_cipher_name)
else:
if not requires_legacy_openssl:
# Disable the TLS 1.3 cipher suites if we are using the modern client
ssl_connection.ssl_client.set_ciphersuites('')
ssl_connection.ssl_client.set_cipher_list(openssl_cipher_name)
if len(ssl_connection.ssl_client.get_cipher_list()) != 1:
raise ValueError(
f'Passed an OpenSSL string for multiple cipher suites: "{openssl_cipher_name}": '
f'{str(ssl_connection.ssl_client.get_cipher_list())}')
try:
# Perform the SSL handshake
ssl_connection.connect()
cipher_result: CipherSuite = AcceptedCipherSuite.from_ongoing_ssl_connection(
ssl_connection, ssl_version)
except SslHandshakeRejected as e:
cipher_result = RejectedCipherSuite(openssl_cipher_name,
ssl_version, str(e))
except ClientCertificateRequested:
# TODO(AD): Sometimes get_current_cipher_name() called in from_ongoing_ssl_connection() will return None
# When the handshake failed due to ClientCertificateRequested
# We need to rewrite this logic to not use OpenSSL for looking up key size and RFC names as it is
# too complicated
# cipher_result = AcceptedCipherSuite.from_ongoing_ssl_connection(ssl_connection, ssl_version)
# The ClientCertificateRequested exception already proves that the cipher suite was accepted
# Workaround here:
cipher_result = AcceptedCipherSuite(openssl_cipher_name,
ssl_version, None, None)
except Exception as e:
cipher_result = ErroredCipherSuite(openssl_cipher_name,
ssl_version, e)
finally:
ssl_connection.close()
return cipher_result
def process_task(
self, server_connectivity_info: ServerConnectivityInfo,
scan_command: PluginScanCommand) -> 'CipherSuiteScanResult':
if not isinstance(scan_command, CipherSuiteScanCommand):
raise ValueError('Unexpected scan command')
ssl_version = self.SSL_VERSIONS_MAPPING[scan_command.__class__]
# Get the list of available cipher suites for the given ssl version
cipher_list: List[str] = []
if ssl_version == OpenSslVersionEnum.TLSV1_2:
# For TLS 1.2, we have to use both the legacy and modern OpenSSL to cover all cipher suites
ssl_connection_legacy = server_connectivity_info.get_preconfigured_ssl_connection(
override_ssl_version=ssl_version,
should_use_legacy_openssl=True)
ssl_connection_legacy.ssl_client.set_cipher_list(
'ALL:COMPLEMENTOFALL:-PSK:-SRP')
cipher_list.extend(
ssl_connection_legacy.ssl_client.get_cipher_list())
ssl_connection_modern = server_connectivity_info.get_preconfigured_ssl_connection(
override_ssl_version=ssl_version,
should_use_legacy_openssl=False)
# Disable the TLS 1.3 cipher suites with the new OpenSSL API
ssl_connection_modern.ssl_client.set_ciphersuites('')
# Enable all other cipher suites
ssl_connection_modern.ssl_client.set_cipher_list(
'ALL:COMPLEMENTOFALL:-PSK:-SRP')
cipher_list.extend(
ssl_connection_modern.ssl_client.get_cipher_list())
# And remove duplicates (ie. supported by both legacy and modern OpenSSL)
cipher_list = list(set(cipher_list))
elif ssl_version == OpenSslVersionEnum.TLSV1_3:
# TLS 1.3 only has 5 cipher suites so we can hardcode them
cipher_list = [
'TLS_AES_256_GCM_SHA384',
'TLS_CHACHA20_POLY1305_SHA256',
'TLS_AES_128_GCM_SHA256',
'TLS_AES_128_CCM_8_SHA256',
'TLS_AES_128_CCM_SHA256',
]
else:
ssl_connection = server_connectivity_info.get_preconfigured_ssl_connection(
override_ssl_version=ssl_version)
# Disable SRP and PSK cipher suites as they need a special setup in the client and are never used
ssl_connection.ssl_client.set_cipher_list(
'ALL:COMPLEMENTOFALL:-PSK:-SRP')
# And remove TLS 1.3 cipher suites
cipher_list = [
cipher
for cipher in ssl_connection.ssl_client.get_cipher_list()
if 'TLS13' not in cipher
]
# Scan for every available cipher suite
thread_pool = ThreadPool()
for cipher in cipher_list:
thread_pool.add_job(
(self._test_cipher_suite,
[server_connectivity_info, ssl_version, cipher]))
# Start processing the jobs; One thread per cipher
thread_pool.start(nb_threads=min(len(cipher_list), self.MAX_THREADS))
accepted_cipher_list = []
rejected_cipher_list = []
errored_cipher_list = []
# Store the results as they come
for completed_job in thread_pool.get_result():
(job, cipher_result) = completed_job
if isinstance(cipher_result, AcceptedCipherSuite):
accepted_cipher_list.append(cipher_result)
elif isinstance(cipher_result, RejectedCipherSuite):
rejected_cipher_list.append(cipher_result)
elif isinstance(cipher_result, ErroredCipherSuite):
errored_cipher_list.append(cipher_result)
else:
raise ValueError('Unexpected result')
# Store thread pool errors; only something completely unexpected would trigger an error
for failed_job in thread_pool.get_error():
(_, exception) = failed_job
raise exception
thread_pool.join()
# Test for the cipher suite preference
preferred_cipher = self._get_preferred_cipher_suite(
server_connectivity_info, ssl_version, accepted_cipher_list)
# Generate the results
plugin_result = CipherSuiteScanResult(server_connectivity_info,
scan_command, preferred_cipher,
accepted_cipher_list,
rejected_cipher_list,
errored_cipher_list)
return plugin_result
def process_task(
self, server_info: ServerConnectivityInfo,
scan_command: PluginScanCommand) -> "HttpHeadersScanResult":
if not isinstance(scan_command, HttpHeadersScanCommand):
raise ValueError("Unexpected scan command")
if server_info.tls_wrapped_protocol not in [
TlsWrappedProtocolEnum.PLAIN_TLS, TlsWrappedProtocolEnum.HTTPS
]:
raise ValueError(
"Cannot test for HTTP headers on a StartTLS connection.")
# Perform the SSL handshake
mozilla_store = TrustStoresRepository.get_default().get_main_store()
ssl_connection = server_info.get_preconfigured_ssl_connection(
ssl_verify_locations=mozilla_store.path)
try:
ssl_connection.connect()
try:
verified_chain_as_pem = ssl_connection.ssl_client.get_verified_chain(
)
except CouldNotBuildVerifiedChain:
verified_chain_as_pem = None
# Send an HTTP GET request to the server
ssl_connection.ssl_client.write(
HttpRequestGenerator.get_request(host=server_info.hostname))
# We do not follow redirections because the security headers must be set on the first page according to
# https://hstspreload.appspot.com/:
# "If you are serving an additional redirect from your HTTPS site, that redirect must still have the HSTS
# header (rather than the page it redirects to)."
http_response = HttpResponseParser.parse_from_ssl_connection(
ssl_connection.ssl_client)
finally:
ssl_connection.close()
if http_response.version == 9:
# HTTP 0.9 => Probably not an HTTP response
raise ValueError("Server did not return an HTTP response")
# Parse the certificate chain
verified_chain = ([
load_pem_x509_certificate(cert_as_pem.encode("ascii"),
backend=default_backend())
for cert_as_pem in verified_chain_as_pem
] if verified_chain_as_pem else None)
# Parse each header
hsts_header = StrictTransportSecurityHeader.from_http_response(
http_response)
expect_ct_header = ExpectCtHeader.from_http_response(http_response)
hpkp_header = PublicKeyPinsHeader.from_http_response(http_response)
hpkp_report_only_header = PublicKeyPinsReportOnlyHeader.from_http_response(
http_response)
return HttpHeadersScanResult(
server_info,
scan_command,
hsts_header,
hpkp_header,
hpkp_report_only_header,
expect_ct_header,
verified_chain,
)
def perform(
self,
network_timeout: Optional[int] = None) -> ServerConnectivityInfo:
"""Attempt to perform a full SSL/TLS handshake with the server.
This method will ensure that the server can be reached, and will also identify one SSL/TLS version and one
cipher suite that is supported by the server.
Args:
network_timeout: Network timeout value in seconds passed to the underlying socket.
Returns:
An object encapsulating all the information needed to connect to the server, to be
passed to a `SynchronousScanner` or `ConcurrentScanner` in order to run scan commands on the server.
Raises:
ServerConnectivityError: If the server was not reachable or an SSL/TLS handshake could not be completed.
"""
# First do a DNS lookup if we don't already have an IP address and we are not using a proxy
if not self.ip_address and not self.http_tunneling_settings:
try:
self.ip_address = self._do_dns_lookup(self.hostname, self.port)
except (socket.gaierror, IndexError, ConnectionError):
raise ServerNotReachableError(
self, self.CONNECTIVITY_ERROR_NAME_NOT_RESOLVED)
# Then try to connect
client_auth_requirement = ClientAuthenticationServerConfigurationEnum.DISABLED
ssl_connection = SslConnectionConfigurator.get_connection(
ssl_version=OpenSslVersionEnum.SSLV23,
server_info=self,
should_ignore_client_auth=True,
)
# First only try a socket connection
try:
ssl_connection.do_pre_handshake(network_timeout=network_timeout)
# Socket errors
except socket.timeout: # Host is down
raise ServerNotReachableError(self,
self.CONNECTIVITY_ERROR_TIMEOUT)
except ConnectionError:
raise ServerNotReachableError(self,
self.CONNECTIVITY_ERROR_REJECTED)
# StartTLS errors
except StartTlsError as e:
raise ServerTlsConfigurationNotSuportedError(self, e.args[0])
# Proxy errors
except ProxyError as e:
raise ProxyConnectivityError(self, e.args[0])
# Other errors
except Exception as e:
raise ServerConnectivityError(
self, '{0}: {1}'.format(str(type(e).__name__), e.args[0]))
finally:
ssl_connection.close()
# Then try to complete an SSL handshake to figure out the SSL version and cipher supported by the server
ssl_version_supported = None
ssl_cipher_supported = None
# TODO(AD): Switch to using the protocol discovery logic available in OpenSSL 1.1.0 with TLS_client_method()
# TODO(AD): Once TLS 1.3 is widely used, put it at the beginning of the list
for ssl_version in [
OpenSslVersionEnum.TLSV1_2, OpenSslVersionEnum.TLSV1_1,
OpenSslVersionEnum.TLSV1, OpenSslVersionEnum.SSLV3,
OpenSslVersionEnum.TLSV1_3, OpenSslVersionEnum.SSLV23
]:
# First try the default cipher list, and then all ciphers
for cipher_list in [
SslConnectionConfigurator.DEFAULT_SSL_CIPHER_LIST,
'ALL:COMPLEMENTOFALL:-PSK:-SRP'
]:
ssl_connection = SslConnectionConfigurator.get_connection(
ssl_version=ssl_version,
server_info=self,
openssl_cipher_string=cipher_list,
should_ignore_client_auth=False,
)
try:
# Only do one attempt when testing connectivity
ssl_connection.connect(network_timeout=network_timeout,
network_max_retries=0)
ssl_version_supported = ssl_version
ssl_cipher_supported = ssl_connection.ssl_client.get_current_cipher_name(
)
except ClientCertificateRequested:
# Connection successful but the servers wants a client certificate which wasn't supplied to sslyze
# Store the SSL version and cipher list that is supported
ssl_version_supported = ssl_version
ssl_cipher_supported = cipher_list
# Close the current connection and try again but ignore client authentication
ssl_connection.close()
# Try a new connection to see if client authentication is optional
ssl_connection_auth = SslConnectionConfigurator.get_connection(
ssl_version=ssl_version,
server_info=self,
openssl_cipher_string=cipher_list,
should_ignore_client_auth=True,
)
try:
ssl_connection_auth.connect(
network_timeout=network_timeout,
network_max_retries=0)
ssl_cipher_supported = ssl_connection_auth.ssl_client.get_current_cipher_name(
)
client_auth_requirement = ClientAuthenticationServerConfigurationEnum.OPTIONAL
# If client authentication is required, we either get a ClientCertificateRequested
except ClientCertificateRequested:
client_auth_requirement = ClientAuthenticationServerConfigurationEnum.REQUIRED
# Or a SSLHandshakeRejected
except SslHandshakeRejected:
client_auth_requirement = ClientAuthenticationServerConfigurationEnum.REQUIRED
# Or a bad certificate alert (https://github.com/nabla-c0d3/sslyze/issues/313 )
except OpenSSLError as e:
if 'alert bad certificate' in e.args[0]:
client_auth_requirement = ClientAuthenticationServerConfigurationEnum.REQUIRED
except Exception:
# Could not complete a handshake with this server
pass
finally:
ssl_connection_auth.close()
except Exception:
# Could not complete a handshake with this server
pass
finally:
ssl_connection.close()
if ssl_cipher_supported:
# A handshake was successful
break
if ssl_version_supported is None or ssl_cipher_supported is None:
raise ServerTlsConfigurationNotSuportedError(
self, self.CONNECTIVITY_ERROR_HANDSHAKE_ERROR)
return ServerConnectivityInfo(
hostname=self.hostname,
port=self.port,
ip_address=self.ip_address,
tls_wrapped_protocol=self.tls_wrapped_protocol,
tls_server_name_indication=self.tls_server_name_indication,
highest_ssl_version_supported=ssl_version_supported,
openssl_cipher_string_supported=ssl_cipher_supported,
client_auth_requirement=client_auth_requirement,
xmpp_to_hostname=self.xmpp_to_hostname,
client_auth_credentials=self.client_auth_credentials,
http_tunneling_settings=self.http_tunneling_settings)
def _test_cipher_suite(
server_connectivity_info: ServerConnectivityInfo,
ssl_version: OpenSslVersionEnum,
openssl_cipher_name: str
) -> 'CipherSuite':
"""Initiates a SSL handshake with the server using the SSL version and the cipher suite specified.
"""
requires_legacy_openssl = True
if ssl_version == OpenSslVersionEnum.TLSV1_2:
# For TLS 1.2, we need to pick the right version of OpenSSL depending on which cipher suite
requires_legacy_openssl = WorkaroundForTls12ForCipherSuites.requires_legacy_openssl(openssl_cipher_name)
elif ssl_version == OpenSslVersionEnum.TLSV1_3:
requires_legacy_openssl = False
ssl_connection = server_connectivity_info.get_preconfigured_ssl_connection(
override_ssl_version=ssl_version,
should_use_legacy_openssl=requires_legacy_openssl
)
# Only enable the cipher suite to test; not trivial anymore since OpenSSL 1.1.1 and TLS 1.3
if ssl_version == OpenSslVersionEnum.TLSV1_3:
# The function to control cipher suites is different for TLS 1.3
# Disable the default, non-TLS 1.3 cipher suites
ssl_connection.ssl_client.set_cipher_list('')
# Enable the one TLS 1.3 cipher suite we want to test
ssl_connection.ssl_client.set_ciphersuites(openssl_cipher_name)
else:
if not requires_legacy_openssl:
# Disable the TLS 1.3 cipher suites if we are using the modern client
ssl_connection.ssl_client.set_ciphersuites('')
ssl_connection.ssl_client.set_cipher_list(openssl_cipher_name)
if len(ssl_connection.ssl_client.get_cipher_list()) != 1:
raise ValueError(f'Passed an OpenSSL string for multiple cipher suites: "{openssl_cipher_name}": '
f'{str(ssl_connection.ssl_client.get_cipher_list())}')
try:
# Perform the SSL handshake
ssl_connection.connect()
cipher_result: CipherSuite = AcceptedCipherSuite.from_ongoing_ssl_connection(ssl_connection, ssl_version)
except SslHandshakeRejected as e:
cipher_result = RejectedCipherSuite(openssl_cipher_name, ssl_version, str(e))
except ClientCertificateRequested:
# TODO(AD): Sometimes get_current_cipher_name() called in from_ongoing_ssl_connection() will return None
# When the handshake failed due to ClientCertificateRequested
# We need to rewrite this logic to not use OpenSSL for looking up key size and RFC names as it is
# too complicated
# cipher_result = AcceptedCipherSuite.from_ongoing_ssl_connection(ssl_connection, ssl_version)
# The ClientCertificateRequested exception already proves that the cipher suite was accepted
# Workaround here:
cipher_result = AcceptedCipherSuite(openssl_cipher_name, ssl_version, None, None)
except Exception as e:
cipher_result = ErroredCipherSuite(openssl_cipher_name, ssl_version, e)
finally:
ssl_connection.close()
return cipher_result
def process_task(
self,
server_connectivity_info: ServerConnectivityInfo,
scan_command: PluginScanCommand
) -> 'CipherSuiteScanResult':
if not isinstance(scan_command, CipherSuiteScanCommand):
raise ValueError('Unexpected scan command')
ssl_version = self.SSL_VERSIONS_MAPPING[scan_command.__class__]
# Get the list of available cipher suites for the given ssl version
cipher_list: List[str] = []
if ssl_version == OpenSslVersionEnum.TLSV1_2:
# For TLS 1.2, we have to use both the legacy and modern OpenSSL to cover all cipher suites
ssl_connection_legacy = server_connectivity_info.get_preconfigured_ssl_connection(
override_ssl_version=ssl_version, should_use_legacy_openssl=True
)
ssl_connection_legacy.ssl_client.set_cipher_list('ALL:COMPLEMENTOFALL:-PSK:-SRP')
cipher_list.extend(ssl_connection_legacy.ssl_client.get_cipher_list())
ssl_connection_modern = server_connectivity_info.get_preconfigured_ssl_connection(
override_ssl_version=ssl_version, should_use_legacy_openssl=False
)
# Disable the TLS 1.3 cipher suites with the new OpenSSL API
ssl_connection_modern.ssl_client.set_ciphersuites('')
# Enable all other cipher suites
ssl_connection_modern.ssl_client.set_cipher_list('ALL:COMPLEMENTOFALL:-PSK:-SRP')
cipher_list.extend(ssl_connection_modern.ssl_client.get_cipher_list())
# And remove duplicates (ie. supported by both legacy and modern OpenSSL)
cipher_list = list(set(cipher_list))
elif ssl_version == OpenSslVersionEnum.TLSV1_3:
# TLS 1.3 only has 5 cipher suites so we can hardcode them
cipher_list = [
'TLS_AES_256_GCM_SHA384',
'TLS_CHACHA20_POLY1305_SHA256',
'TLS_AES_128_GCM_SHA256',
'TLS_AES_128_CCM_8_SHA256',
'TLS_AES_128_CCM_SHA256',
]
else:
ssl_connection = server_connectivity_info.get_preconfigured_ssl_connection(override_ssl_version=ssl_version)
# Disable SRP and PSK cipher suites as they need a special setup in the client and are never used
ssl_connection.ssl_client.set_cipher_list('ALL:COMPLEMENTOFALL:-PSK:-SRP')
# And remove TLS 1.3 cipher suites
cipher_list = [cipher for cipher in ssl_connection.ssl_client.get_cipher_list() if 'TLS13' not in cipher]
# Scan for every available cipher suite
thread_pool = ThreadPool()
for cipher in cipher_list:
thread_pool.add_job((self._test_cipher_suite, [server_connectivity_info, ssl_version, cipher]))
# Start processing the jobs; One thread per cipher
thread_pool.start(nb_threads=min(len(cipher_list), self.MAX_THREADS))
accepted_cipher_list = []
rejected_cipher_list = []
errored_cipher_list = []
# Store the results as they come
for completed_job in thread_pool.get_result():
(job, cipher_result) = completed_job
if isinstance(cipher_result, AcceptedCipherSuite):
accepted_cipher_list.append(cipher_result)
elif isinstance(cipher_result, RejectedCipherSuite):
rejected_cipher_list.append(cipher_result)
elif isinstance(cipher_result, ErroredCipherSuite):
errored_cipher_list.append(cipher_result)
else:
raise ValueError('Unexpected result')
# Store thread pool errors; only something completely unexpected would trigger an error
for failed_job in thread_pool.get_error():
(_, exception) = failed_job
raise exception
thread_pool.join()
# Test for the cipher suite preference
preferred_cipher = self._get_preferred_cipher_suite(server_connectivity_info, ssl_version, accepted_cipher_list)
# Generate the results
plugin_result = CipherSuiteScanResult(server_connectivity_info, scan_command, preferred_cipher,
accepted_cipher_list, rejected_cipher_list, errored_cipher_list)
return plugin_result
