# Author: Trevor Perrin
# See the LICENSE file for legal information regarding use of this file.
"""Class representing an X.509 certificate chain."""
from .utils import cryptomath
from .utils.tackwrapper import *
from .utils.pem import *
from .x509 import X509
[docs]
class X509CertChain(object):
"""This class represents a chain of X.509 certificates.
:vartype x509List: list
:ivar x509List: A list of :py:class:`tlslite.x509.X509` instances,
starting with the end-entity certificate and with every
subsequent certificate certifying the previous.
"""
[docs]
def __init__(self, x509List=None):
"""Create a new X509CertChain.
:type x509List: list
:param x509List: A list of :py:class:`tlslite.x509.X509` instances,
starting with the end-entity certificate and with every
subsequent certificate certifying the previous.
"""
if x509List:
self.x509List = x509List
else:
self.x509List = []
def __hash__(self):
"""Return hash of the object."""
return hash(tuple(self.x509List))
def __eq__(self, other):
"""Compare objects with each-other."""
if not hasattr(other, "x509List"):
return NotImplemented
return self.x509List == other.x509List
def __ne__(self, other):
"""Compare object for inequality."""
if not hasattr(other, "x509List"):
return NotImplemented
return self.x509List != other.x509List
[docs]
def parsePemList(self, s):
"""Parse a string containing a sequence of PEM certs.
Raise a SyntaxError if input is malformed.
"""
x509List = []
bList = dePemList(s, "CERTIFICATE")
for b in bList:
x509 = X509()
x509.parseBinary(b)
x509List.append(x509)
self.x509List = x509List
[docs]
def getNumCerts(self):
"""Get the number of certificates in this chain.
:rtype: int
"""
return len(self.x509List)
[docs]
def getEndEntityPublicKey(self):
"""Get the public key from the end-entity certificate.
:rtype: ~tlslite.utils.rsakey.RSAKey`
"""
if self.getNumCerts() == 0:
raise AssertionError()
return self.x509List[0].publicKey
[docs]
def getFingerprint(self):
"""Get the hex-encoded fingerprint of the end-entity certificate.
:rtype: str
:returns: A hex-encoded fingerprint.
"""
if self.getNumCerts() == 0:
raise AssertionError()
return self.x509List[0].getFingerprint()
[docs]
def checkTack(self, tack):
if self.x509List:
tlsCert = TlsCertificate(self.x509List[0].bytes)
if tlsCert.matches(tack):
return True
return False
[docs]
def getTackExt(self):
"""Get the TACK and/or Break Sigs from a TACK Cert in the chain."""
tackExt = None
# Search list in backwards order
for x509 in self.x509List[::-1]:
tlsCert = TlsCertificate(x509.bytes)
if tlsCert.tackExt:
if tackExt:
raise SyntaxError("Multiple TACK Extensions")
else:
tackExt = tlsCert.tackExt
return tackExt