blob: c7f7ba81d4d227dbc8304192e7a9077a9b8eacdc [file] [log] [blame]
"""Exception classes.
@sort: TLSError, TLSAbruptCloseError, TLSAlert, TLSLocalAlert, TLSRemoteAlert,
TLSAuthenticationError, TLSNoAuthenticationError, TLSAuthenticationTypeError,
TLSFingerprintError, TLSAuthorizationError, TLSValidationError, TLSFaultError
"""
from constants import AlertDescription, AlertLevel
class TLSError(Exception):
"""Base class for all TLS Lite exceptions."""
pass
class TLSAbruptCloseError(TLSError):
"""The socket was closed without a proper TLS shutdown.
The TLS specification mandates that an alert of some sort
must be sent before the underlying socket is closed. If the socket
is closed without this, it could signify that an attacker is trying
to truncate the connection. It could also signify a misbehaving
TLS implementation, or a random network failure.
"""
pass
class TLSAlert(TLSError):
"""A TLS alert has been signalled."""
pass
_descriptionStr = {\
AlertDescription.close_notify: "close_notify",\
AlertDescription.unexpected_message: "unexpected_message",\
AlertDescription.bad_record_mac: "bad_record_mac",\
AlertDescription.decryption_failed: "decryption_failed",\
AlertDescription.record_overflow: "record_overflow",\
AlertDescription.decompression_failure: "decompression_failure",\
AlertDescription.handshake_failure: "handshake_failure",\
AlertDescription.no_certificate: "no certificate",\
AlertDescription.bad_certificate: "bad_certificate",\
AlertDescription.unsupported_certificate: "unsupported_certificate",\
AlertDescription.certificate_revoked: "certificate_revoked",\
AlertDescription.certificate_expired: "certificate_expired",\
AlertDescription.certificate_unknown: "certificate_unknown",\
AlertDescription.illegal_parameter: "illegal_parameter",\
AlertDescription.unknown_ca: "unknown_ca",\
AlertDescription.access_denied: "access_denied",\
AlertDescription.decode_error: "decode_error",\
AlertDescription.decrypt_error: "decrypt_error",\
AlertDescription.export_restriction: "export_restriction",\
AlertDescription.protocol_version: "protocol_version",\
AlertDescription.insufficient_security: "insufficient_security",\
AlertDescription.internal_error: "internal_error",\
AlertDescription.user_canceled: "user_canceled",\
AlertDescription.no_renegotiation: "no_renegotiation",\
AlertDescription.unknown_srp_username: "unknown_srp_username",\
AlertDescription.missing_srp_username: "missing_srp_username"}
class TLSLocalAlert(TLSAlert):
"""A TLS alert has been signalled by the local implementation.
@type description: int
@ivar description: Set to one of the constants in
L{tlslite.constants.AlertDescription}
@type level: int
@ivar level: Set to one of the constants in
L{tlslite.constants.AlertLevel}
@type message: str
@ivar message: Description of what went wrong.
"""
def __init__(self, alert, message=None):
self.description = alert.description
self.level = alert.level
self.message = message
def __str__(self):
alertStr = TLSAlert._descriptionStr.get(self.description)
if alertStr == None:
alertStr = str(self.description)
if self.message:
return alertStr + ": " + self.message
else:
return alertStr
class TLSRemoteAlert(TLSAlert):
"""A TLS alert has been signalled by the remote implementation.
@type description: int
@ivar description: Set to one of the constants in
L{tlslite.constants.AlertDescription}
@type level: int
@ivar level: Set to one of the constants in
L{tlslite.constants.AlertLevel}
"""
def __init__(self, alert):
self.description = alert.description
self.level = alert.level
def __str__(self):
alertStr = TLSAlert._descriptionStr.get(self.description)
if alertStr == None:
alertStr = str(self.description)
return alertStr
class TLSAuthenticationError(TLSError):
"""The handshake succeeded, but the other party's authentication
was inadequate.
This exception will only be raised when a
L{tlslite.Checker.Checker} has been passed to a handshake function.
The Checker will be invoked once the handshake completes, and if
the Checker objects to how the other party authenticated, a
subclass of this exception will be raised.
"""
pass
class TLSNoAuthenticationError(TLSAuthenticationError):
"""The Checker was expecting the other party to authenticate with a
certificate chain, but this did not occur."""
pass
class TLSAuthenticationTypeError(TLSAuthenticationError):
"""The Checker was expecting the other party to authenticate with a
different type of certificate chain."""
pass
class TLSFingerprintError(TLSAuthenticationError):
"""The Checker was expecting the other party to authenticate with a
certificate chain that matches a different fingerprint."""
pass
class TLSAuthorizationError(TLSAuthenticationError):
"""The Checker was expecting the other party to authenticate with a
certificate chain that has a different authorization."""
pass
class TLSValidationError(TLSAuthenticationError):
"""The Checker has determined that the other party's certificate
chain is invalid."""
pass
class TLSFaultError(TLSError):
"""The other party responded incorrectly to an induced fault.
This exception will only occur during fault testing, when a
TLSConnection's fault variable is set to induce some sort of
faulty behavior, and the other party doesn't respond appropriately.
"""
pass