-##
-# Geniwrapper uses two crypto libraries: pyOpenSSL and M2Crypto to implement
+# ----------------------------------------------------------------------
+# Copyright (c) 2008 Board of Trustees, Princeton University
+#
+# Permission is hereby granted, free of charge, to any person obtaining
+# a copy of this software and/or hardware specification (the "Work") to
+# deal in the Work without restriction, including without limitation the
+# rights to use, copy, modify, merge, publish, distribute, sublicense,
+# and/or sell copies of the Work, and to permit persons to whom the Work
+# is furnished to do so, subject to the following conditions:
+#
+# The above copyright notice and this permission notice shall be
+# included in all copies or substantial portions of the Work.
+#
+# THE WORK IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+# OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
+# HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+# WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE WORK OR THE USE OR OTHER DEALINGS
+# IN THE WORK.
+# ----------------------------------------------------------------------
+
+#
+# SFA uses two crypto libraries: pyOpenSSL and M2Crypto to implement
# the necessary crypto functionality. Ideally just one of these libraries
# would be used, but unfortunately each of these libraries is independently
# lacking. The pyOpenSSL library is missing many necessary functions, and
# This module exports two classes: Keypair and Certificate.
##
#
-### $Id$
-### $URL$
+
+# Notes on using the openssl command line
+#
+# for verifying the chain in a gid,
+# assuming it is split into pieces p1.pem p2.pem p3.pem
+# you can use openssl to verify the chain using this command
+# openssl verify -verbose -CAfile <(cat p2.pem p3.pem) p1.pem
+# also you can use sfax509 to invoke openssl x509 on all parts of the gid
#
+
+from __future__ import print_function
+
+import functools
import os
import tempfile
import base64
-from OpenSSL import crypto
-import M2Crypto
-from M2Crypto import X509
-from M2Crypto import EVP
+from tempfile import mkstemp
+
+import OpenSSL
+# M2Crypto is imported on the fly to minimize crashes
+# import M2Crypto
+
+from sfa.util.py23 import PY3
+
+from sfa.util.faults import (CertExpired, CertMissingParent,
+ CertNotSignedByParent)
+from sfa.util.sfalogging import logger
+
+# this tends to generate quite some logs for little or no value
+debug_verify_chain = False
+
+glo_passphrase_callback = None
+
+##
+# A global callback may be implemented for requesting passphrases from the
+# user. The function will be called with three arguments:
+#
+# keypair_obj: the keypair object that is calling the passphrase
+# string: the string containing the private key that's being loaded
+# x: unknown, appears to be 0, comes from pyOpenSSL and/or m2crypto
+#
+# The callback should return a string containing the passphrase.
+
+
+def set_passphrase_callback(callback_func):
+ global glo_passphrase_callback
+
+ glo_passphrase_callback = callback_func
+
+##
+# Sets a fixed passphrase.
+
+
+def set_passphrase(passphrase):
+ set_passphrase_callback(lambda k, s, x: passphrase)
+
+##
+# Check to see if a passphrase works for a particular private key string.
+# Intended to be used by passphrase callbacks for input validation.
+
+
+def test_passphrase(string, passphrase):
+ try:
+ OpenSSL.crypto.load_privatekey(
+ OpenSSL.crypto.FILETYPE_PEM, string, (lambda x: passphrase))
+ return True
+ except:
+ return False
-from sfa.util.faults import *
def convert_public_key(key):
- keyconvert_path = "/usr/bin/keyconvert"
+ keyconvert_path = "/usr/bin/keyconvert.py"
if not os.path.isfile(keyconvert_path):
- raise IOError, "Could not find keyconvert in %s" % keyconvert_path
+ raise IOError(
+ "Could not find keyconvert in {}".format(keyconvert_path))
- # we can only convert rsa keys
+ # we can only convert rsa keys
if "ssh-dss" in key:
- print "XXX: DSA key encountered, ignoring"
- return None
-
+ raise Exception("keyconvert: dss keys are not supported")
+
(ssh_f, ssh_fn) = tempfile.mkstemp()
ssl_fn = tempfile.mktemp()
os.write(ssh_f, key)
# that it can be expected to see why it failed.
# TODO: for production, cleanup the temporary files
if not os.path.exists(ssl_fn):
- report.trace(" failed to convert key from " + ssh_fn + " to " + ssl_fn)
- return None
+ raise Exception(
+ "generated certificate not found. keyconvert may have failed.")
k = Keypair()
try:
k.load_pubkey_from_file(ssl_fn)
+ return k
except:
- print "XXX: Error while converting key: ", key_str
- k = None
-
- # remove the temporary files
- os.remove(ssh_fn)
- os.remove(ssl_fn)
-
- return k
+ logger.log_exc("convert_public_key caught exception")
+ raise
+ finally:
+ # remove the temporary files
+ if os.path.exists(ssh_fn):
+ os.remove(ssh_fn)
+ if os.path.exists(ssl_fn):
+ os.remove(ssl_fn)
##
# Public-private key pairs are implemented by the Keypair class.
# A Keypair object may represent both a public and private key pair, or it
# may represent only a public key (this usage is consistent with OpenSSL).
+
class Keypair:
- key = None # public/private keypair
- m2key = None # public key (m2crypto format)
-
- ##
- # Creates a Keypair object
- # @param create If create==True, creates a new public/private key and
- # stores it in the object
- # @param string If string!=None, load the keypair from the string (PEM)
- # @param filename If filename!=None, load the keypair from the file
-
- def __init__(self, create=False, string=None, filename=None):
- if create:
- self.create()
- if string:
- self.load_from_string(string)
- if filename:
- self.load_from_file(filename)
-
- ##
- # Create a RSA public/private key pair and store it inside the keypair object
-
- def create(self):
- self.key = crypto.PKey()
- self.key.generate_key(crypto.TYPE_RSA, 1024)
-
- ##
- # Save the private key to a file
- # @param filename name of file to store the keypair in
-
- def save_to_file(self, filename):
- open(filename, 'w').write(self.as_pem())
-
- ##
- # Load the private key from a file. Implicity the private key includes the public key.
-
- def load_from_file(self, filename):
- buffer = open(filename, 'r').read()
- self.load_from_string(buffer)
-
- ##
- # Load the private key from a string. Implicitly the private key includes the public key.
-
- def load_from_string(self, string):
- self.key = crypto.load_privatekey(crypto.FILETYPE_PEM, string)
- self.m2key = M2Crypto.EVP.load_key_string(string)
-
- ##
- # Load the public key from a string. No private key is loaded.
-
- def load_pubkey_from_file(self, filename):
- # load the m2 public key
- m2rsakey = M2Crypto.RSA.load_pub_key(filename)
- self.m2key = M2Crypto.EVP.PKey()
- self.m2key.assign_rsa(m2rsakey)
-
- # create an m2 x509 cert
- m2name = M2Crypto.X509.X509_Name()
- m2name.add_entry_by_txt(field="CN", type=0x1001, entry="junk", len=-1, loc=-1, set=0)
- m2x509 = M2Crypto.X509.X509()
- m2x509.set_pubkey(self.m2key)
- m2x509.set_serial_number(0)
- m2x509.set_issuer_name(m2name)
- m2x509.set_subject_name(m2name)
- ASN1 = M2Crypto.ASN1.ASN1_UTCTIME()
- ASN1.set_time(500)
- m2x509.set_not_before(ASN1)
- m2x509.set_not_after(ASN1)
- junk_key = Keypair(create=True)
- m2x509.sign(pkey=junk_key.get_m2_pkey(), md="sha1")
-
- # convert the m2 x509 cert to a pyopenssl x509
- m2pem = m2x509.as_pem()
- pyx509 = crypto.load_certificate(crypto.FILETYPE_PEM, m2pem)
-
- # get the pyopenssl pkey from the pyopenssl x509
- self.key = pyx509.get_pubkey()
-
- ##
- # Load the public key from a string. No private key is loaded.
-
- def load_pubkey_from_string(self, string):
- (f, fn) = tempfile.mkstemp()
- os.write(f, string)
- os.close(f)
- self.load_pubkey_from_file(fn)
- os.remove(fn)
-
- ##
- # Return the private key in PEM format.
-
- def as_pem(self):
- return crypto.dump_privatekey(crypto.FILETYPE_PEM, self.key)
-
- ##
- # Return an M2Crypto key object
-
- def get_m2_pkey(self):
- if not self.m2key:
- self.m2key = M2Crypto.EVP.load_key_string(self.as_pem())
- return self.m2key
-
- ##
- # Returns a string containing the public key represented by this object.
-
- def get_pubkey_string(self):
- m2pkey = self.get_m2_pkey()
- return base64.b64encode(m2pkey.as_der())
-
- ##
- # Return an OpenSSL pkey object
-
- def get_openssl_pkey(self):
- return self.key
-
- ##
- # Given another Keypair object, return TRUE if the two keys are the same.
-
- def is_same(self, pkey):
- return self.as_pem() == pkey.as_pem()
-
- def sign_string(self, data):
- k = self.get_m2_pkey()
- k.sign_init()
- k.sign_update(data)
- return base64.b64encode(k.sign_final())
-
- def verify_string(self, data, sig):
- k = self.get_m2_pkey()
- k.verify_init()
- k.verify_update(data)
- return M2Crypto.m2.verify_final(k.ctx, base64.b64decode(sig), k.pkey)
+ key = None # public/private keypair
+ m2key = None # public key (m2crypto format)
+
+ ##
+ # Creates a Keypair object
+ # @param create If create==True, creates a new public/private key and
+ # stores it in the object
+ # @param string If string != None, load the keypair from the string (PEM)
+ # @param filename If filename != None, load the keypair from the file
+
+ def __init__(self, create=False, string=None, filename=None):
+ if create:
+ self.create()
+ if string:
+ self.load_from_string(string)
+ if filename:
+ self.load_from_file(filename)
+
+ ##
+ # Create a RSA public/private key pair and store it inside the keypair
+ # object
+
+ def create(self):
+ self.key = OpenSSL.crypto.PKey()
+ self.key.generate_key(OpenSSL.crypto.TYPE_RSA, 2048)
+
+ ##
+ # Save the private key to a file
+ # @param filename name of file to store the keypair in
+
+ def save_to_file(self, filename):
+ open(filename, 'w').write(self.as_pem())
+ self.filename = filename
+
+ ##
+ # Load the private key from a file. Implicity the private key includes the
+ # public key.
+
+ def load_from_file(self, filename):
+ self.filename = filename
+ buffer = open(filename, 'r').read()
+ self.load_from_string(buffer)
+
+ ##
+ # Load the private key from a string. Implicitly the private key includes
+ # the public key.
+
+ def load_from_string(self, string):
+ import M2Crypto
+ if glo_passphrase_callback:
+ self.key = OpenSSL.crypto.load_privatekey(
+ OpenSSL.crypto.FILETYPE_PEM, string,
+ functools.partial(glo_passphrase_callback, self, string))
+ self.m2key = M2Crypto.EVP.load_key_string(
+ string, functools.partial(glo_passphrase_callback,
+ self, string))
+ else:
+ self.key = OpenSSL.crypto.load_privatekey(
+ OpenSSL.crypto.FILETYPE_PEM, string)
+ self.m2key = M2Crypto.EVP.load_key_string(string)
+
+ ##
+ # Load the public key from a string. No private key is loaded.
+
+ def load_pubkey_from_file(self, filename):
+ import M2Crypto
+ # load the m2 public key
+ m2rsakey = M2Crypto.RSA.load_pub_key(filename)
+ self.m2key = M2Crypto.EVP.PKey()
+ self.m2key.assign_rsa(m2rsakey)
+
+ # create an m2 x509 cert
+ m2name = M2Crypto.X509.X509_Name()
+ m2name.add_entry_by_txt(field="CN", type=0x1001,
+ entry="junk", len=-1, loc=-1, set=0)
+ m2x509 = M2Crypto.X509.X509()
+ m2x509.set_pubkey(self.m2key)
+ m2x509.set_serial_number(0)
+ m2x509.set_issuer_name(m2name)
+ m2x509.set_subject_name(m2name)
+ ASN1 = M2Crypto.ASN1.ASN1_UTCTIME()
+ ASN1.set_time(500)
+ m2x509.set_not_before(ASN1)
+ m2x509.set_not_after(ASN1)
+ # x509v3 so it can have extensions
+ # prob not necc since this cert itself is junk but still...
+ m2x509.set_version(2)
+ junk_key = Keypair(create=True)
+ m2x509.sign(pkey=junk_key.get_m2_pubkey(), md="sha1")
+
+ # convert the m2 x509 cert to a pyopenssl x509
+ m2pem = m2x509.as_pem()
+ pyx509 = OpenSSL.crypto.load_certificate(
+ OpenSSL.crypto.FILETYPE_PEM, m2pem)
+
+ # get the pyopenssl pkey from the pyopenssl x509
+ self.key = pyx509.get_pubkey()
+ self.filename = filename
+
+ ##
+ # Load the public key from a string. No private key is loaded.
+
+ def load_pubkey_from_string(self, string):
+ (f, fn) = tempfile.mkstemp()
+ os.write(f, string)
+ os.close(f)
+ self.load_pubkey_from_file(fn)
+ os.remove(fn)
+
+ ##
+ # Return the private key in PEM format.
+
+ def as_pem(self):
+ return OpenSSL.crypto.dump_privatekey(
+ OpenSSL.crypto.FILETYPE_PEM, self.key)
+
+ ##
+ # Return an M2Crypto key object
+
+ def get_m2_pubkey(self):
+ import M2Crypto
+ if not self.m2key:
+ self.m2key = M2Crypto.EVP.load_key_string(self.as_pem())
+ return self.m2key
+
+ ##
+ # Returns a string containing the public key represented by this object.
+
+ def get_pubkey_string(self):
+ m2pkey = self.get_m2_pubkey()
+ return base64.b64encode(m2pkey.as_der())
+
+ ##
+ # Return an OpenSSL pkey object
+
+ def get_openssl_pkey(self):
+ return self.key
+
+ ##
+ # Given another Keypair object, return TRUE if the two keys are the same.
+
+ def is_same(self, pkey):
+ return self.as_pem() == pkey.as_pem()
+
+ def sign_string(self, data):
+ k = self.get_m2_pubkey()
+ k.sign_init()
+ k.sign_update(data)
+ return base64.b64encode(k.sign_final())
+
+ def verify_string(self, data, sig):
+ import M2Crypto
+ k = self.get_m2_pubkey()
+ k.verify_init()
+ k.verify_update(data)
+ return M2Crypto.m2.verify_final(k.ctx, base64.b64decode(sig), k.pkey)
+
+ def compute_hash(self, value):
+ return self.sign_string(str(value))
+
+ # only informative
+ def get_filename(self):
+ return getattr(self, 'filename', None)
+
+ def dump(self, *args, **kwargs):
+ print(self.dump_string(*args, **kwargs))
+
+ def dump_string(self):
+ result = ""
+ result += "KEYPAIR: pubkey={:>40}...".format(self.get_pubkey_string())
+ filename = self.get_filename()
+ if filename:
+ result += "Filename {}\n".format(filename)
+ return result
##
# The certificate class implements a general purpose X509 certificate, making
# When saving a certificate to a file or a string, the caller can choose
# whether to save the parent certificates as well.
+
class Certificate:
- digest = "md5"
-
- data = None
- cert = None
- issuerKey = None
- issuerSubject = None
- parent = None
-
- separator="-----parent-----"
-
- ##
- # Create a certificate object.
- #
- # @param create If create==True, then also create a blank X509 certificate.
- # @param subject If subject!=None, then create a blank certificate and set
- # it's subject name.
- # @param string If string!=None, load the certficate from the string.
- # @param filename If filename!=None, load the certficiate from the file.
-
- def __init__(self, create=False, subject=None, string=None, filename=None):
- if create or subject:
- self.create()
- if subject:
- self.set_subject(subject)
- if string:
- self.load_from_string(string)
- if filename:
- self.load_from_file(filename)
-
- ##
- # Create a blank X509 certificate and store it in this object.
-
- def create(self):
- self.cert = crypto.X509()
- self.cert.set_serial_number(1)
- self.cert.gmtime_adj_notBefore(0)
- self.cert.gmtime_adj_notAfter(60*60*24*365*5) # five years
-
- ##
- # Given a pyOpenSSL X509 object, store that object inside of this
- # certificate object.
-
- def load_from_pyopenssl_x509(self, x509):
- self.cert = x509
-
- ##
- # Load the certificate from a string
-
- def load_from_string(self, string):
- # if it is a chain of multiple certs, then split off the first one and
- # load it
- parts = string.split(Certificate.separator, 1)
- self.cert = crypto.load_certificate(crypto.FILETYPE_PEM, parts[0])
-
- # if there are more certs, then create a parent and let the parent load
- # itself from the remainder of the string
- if len(parts) > 1:
- self.parent = self.__class__()
- self.parent.load_from_string(parts[1])
-
- ##
- # Load the certificate from a file
-
- def load_from_file(self, filename):
- file = open(filename)
- string = file.read()
- self.load_from_string(string)
-
- ##
- # Save the certificate to a string.
- #
- # @param save_parents If save_parents==True, then also save the parent certificates.
-
- def save_to_string(self, save_parents=False):
- string = crypto.dump_certificate(crypto.FILETYPE_PEM, self.cert)
- if save_parents and self.parent:
- string = string + Certificate.separator + self.parent.save_to_string(save_parents)
- return string
-
- ##
- # Save the certificate to a file.
- # @param save_parents If save_parents==True, then also save the parent certificates.
-
- def save_to_file(self, filename, save_parents=False):
- string = self.save_to_string(save_parents=save_parents)
- open(filename, 'w').write(string)
-
- ##
- # Sets the issuer private key and name
- # @param key Keypair object containing the private key of the issuer
- # @param subject String containing the name of the issuer
- # @param cert (optional) Certificate object containing the name of the issuer
-
- def set_issuer(self, key, subject=None, cert=None):
- self.issuerKey = key
- if subject:
- # it's a mistake to use subject and cert params at the same time
- assert(not cert)
- if isinstance(subject, dict) or isinstance(subject, str):
- req = crypto.X509Req()
- reqSubject = req.get_subject()
- if (isinstance(subject, dict)):
- for key in reqSubject.keys():
- setattr(reqSubject, key, name[key])
- else:
- setattr(reqSubject, "CN", subject)
- subject = reqSubject
- # subject is not valid once req is out of scope, so save req
- self.issuerReq = req
- if cert:
- # if a cert was supplied, then get the subject from the cert
- subject = cert.cert.get_issuer()
- assert(subject)
- self.issuerSubject = subject
-
- ##
- # Get the issuer name
-
- def get_issuer(self, which="CN"):
- x = self.cert.get_issuer()
- return getattr(x, which)
-
- ##
- # Set the subject name of the certificate
-
- def set_subject(self, name):
- req = crypto.X509Req()
- subj = req.get_subject()
- if (isinstance(name, dict)):
- for key in name.keys():
- setattr(subj, key, name[key])
- else:
- setattr(subj, "CN", name)
- self.cert.set_subject(subj)
- ##
- # Get the subject name of the certificate
-
- def get_subject(self, which="CN"):
- x = self.cert.get_subject()
- return getattr(x, which)
-
- ##
- # Get the public key of the certificate.
- #
- # @param key Keypair object containing the public key
-
- def set_pubkey(self, key):
- assert(isinstance(key, Keypair))
- self.cert.set_pubkey(key.get_openssl_pkey())
-
- ##
- # Get the public key of the certificate.
- # It is returned in the form of a Keypair object.
-
- def get_pubkey(self):
- m2x509 = X509.load_cert_string(self.save_to_string())
- pkey = Keypair()
- pkey.key = self.cert.get_pubkey()
- pkey.m2key = m2x509.get_pubkey()
- return pkey
-
- ##
- # Add an X509 extension to the certificate. Add_extension can only be called
- # once for a particular extension name, due to limitations in the underlying
- # library.
- #
- # @param name string containing name of extension
- # @param value string containing value of the extension
-
- def add_extension(self, name, critical, value):
- ext = crypto.X509Extension (name, critical, value)
- self.cert.add_extensions([ext])
-
- ##
- # Get an X509 extension from the certificate
-
- def get_extension(self, name):
- # pyOpenSSL does not have a way to get extensions
- m2x509 = X509.load_cert_string(self.save_to_string())
- value = m2x509.get_ext(name).get_value()
- return value
-
- ##
- # Set_data is a wrapper around add_extension. It stores the parameter str in
- # the X509 subject_alt_name extension. Set_data can only be called once, due
- # to limitations in the underlying library.
-
- def set_data(self, str):
- # pyOpenSSL only allows us to add extensions, so if we try to set the
- # same extension more than once, it will not work
- if self.data != None:
- raise "cannot set subjectAltName more than once"
- self.data = str
- self.add_extension("subjectAltName", 0, "URI:http://" + str)
-
- ##
- # Return the data string that was previously set with set_data
-
- def get_data(self):
- if self.data:
- return self.data
-
- try:
- uri = self.get_extension("subjectAltName")
- except LookupError:
- self.data = None
- return self.data
-
- if not uri.startswith("URI:http://"):
- raise "bad encoding in subjectAltName"
- self.data = uri[11:]
- return self.data
-
- ##
- # Sign the certificate using the issuer private key and issuer subject previous set with set_issuer().
-
- def sign(self):
- assert self.cert != None
- assert self.issuerSubject != None
- assert self.issuerKey != None
- self.cert.set_issuer(self.issuerSubject)
- self.cert.sign(self.issuerKey.get_openssl_pkey(), self.digest)
+ digest = "sha256"
+
+# x509 = None
+# issuerKey = None
+# issuerSubject = None
+# parent = None
+ isCA = None # will be a boolean once set
+
+ separator = "-----parent-----"
+
+ ##
+ # Create a certificate object.
+ #
+ # @param lifeDays life of cert in days - default is 1825==5 years
+ # @param create If create==True, then also create a blank X509 certificate.
+ # @param subject If subject!=None, then create a blank certificate and set
+ # it's subject name.
+ # @param string If string!=None, load the certficate from the string.
+ # @param filename If filename!=None, load the certficiate from the file.
+ # @param isCA If !=None, set whether this cert is for a CA
+
+ def __init__(self, lifeDays=1825, create=False, subject=None, string=None,
+ filename=None, isCA=None):
+ # these used to be defined in the class !
+ self.x509 = None
+ self.issuerKey = None
+ self.issuerSubject = None
+ self.parent = None
+
+ self.data = {}
+ if create or subject:
+ self.create(lifeDays)
+ if subject:
+ self.set_subject(subject)
+ if string:
+ self.load_from_string(string)
+ if filename:
+ self.load_from_file(filename)
+
+ # Set the CA bit if a value was supplied
+ if isCA is not None:
+ self.set_is_ca(isCA)
+
+ # Create a blank X509 certificate and store it in this object.
+
+ def create(self, lifeDays=1825):
+ self.x509 = OpenSSL.crypto.X509()
+ # FIXME: Use different serial #s
+ self.x509.set_serial_number(3)
+ self.x509.gmtime_adj_notBefore(0) # 0 means now
+ self.x509.gmtime_adj_notAfter(
+ lifeDays * 60 * 60 * 24) # five years is default
+ self.x509.set_version(2) # x509v3 so it can have extensions
+
+ ##
+ # Given a pyOpenSSL X509 object, store that object inside of this
+ # certificate object.
+
+ def load_from_pyopenssl_x509(self, x509):
+ self.x509 = x509
+
+ ##
+ # Load the certificate from a string
+
+ def load_from_string(self, string):
+ # if it is a chain of multiple certs, then split off the first one and
+ # load it (support for the ---parent--- tag as well as normal chained
+ # certs)
+
+ if string is None or string.strip() == "":
+ logger.warn("Empty string in load_from_string")
+ return
+
+ string = string.strip()
+
+ # If it's not in proper PEM format, wrap it
+ if string.count('-----BEGIN CERTIFICATE') == 0:
+ string = '-----BEGIN CERTIFICATE-----'\
+ '\n{}\n-----END CERTIFICATE-----'\
+ .format(string)
+
+ # If there is a PEM cert in there, but there is some other text first
+ # such as the text of the certificate, skip the text
+ beg = string.find('-----BEGIN CERTIFICATE')
+ if beg > 0:
+ # skipping over non cert beginning
+ string = string[beg:]
+
+ parts = []
+
+ if string.count('-----BEGIN CERTIFICATE-----') > 1 and \
+ string.count(Certificate.separator) == 0:
+ parts = string.split('-----END CERTIFICATE-----', 1)
+ parts[0] += '-----END CERTIFICATE-----'
+ else:
+ parts = string.split(Certificate.separator, 1)
+
+ self.x509 = OpenSSL.crypto.load_certificate(
+ OpenSSL.crypto.FILETYPE_PEM, parts[0])
+
+ if self.x509 is None:
+ logger.warn(
+ "Loaded from string but cert is None: {}".format(string))
+
+ # if there are more certs, then create a parent and let the parent load
+ # itself from the remainder of the string
+ if len(parts) > 1 and parts[1] != '':
+ self.parent = self.__class__()
+ self.parent.load_from_string(parts[1])
+
+ ##
+ # Load the certificate from a file
+
+ def load_from_file(self, filename):
+ file = open(filename)
+ string = file.read()
+ self.load_from_string(string)
+ self.filename = filename
+
+ ##
+ # Save the certificate to a string.
+ #
+ # @param save_parents If save_parents==True,
+ # then also save the parent certificates.
+
+ def save_to_string(self, save_parents=True):
+ if self.x509 is None:
+ logger.warn("None cert in certificate.save_to_string")
+ return ""
+ string = OpenSSL.crypto.dump_certificate(
+ OpenSSL.crypto.FILETYPE_PEM, self.x509)
+ if PY3 and isinstance(string, bytes):
+ string = string.decode()
+ if save_parents and self.parent:
+ string = string + self.parent.save_to_string(save_parents)
+ return string
+
+ ##
+ # Save the certificate to a file.
+ # @param save_parents If save_parents==True,
+ # then also save the parent certificates.
+
+ def save_to_file(self, filename, save_parents=True, filep=None):
+ string = self.save_to_string(save_parents=save_parents)
+ if filep:
+ f = filep
+ else:
+ f = open(filename, 'w')
+ if PY3 and isinstance(string, bytes):
+ string = string.decode()
+ f.write(string)
+ f.close()
+ self.filename = filename
+
+ ##
+ # Save the certificate to a random file in /tmp/
+ # @param save_parents If save_parents==True,
+ # then also save the parent certificates.
+ def save_to_random_tmp_file(self, save_parents=True):
+ fp, filename = mkstemp(suffix='cert', text=True)
+ fp = os.fdopen(fp, "w")
+ self.save_to_file(filename, save_parents=True, filep=fp)
+ return filename
+
+ ##
+ # Sets the issuer private key and name
+ # @param key Keypair object containing the private key of the issuer
+ # @param subject String containing the name of the issuer
+ # @param cert (optional)
+ # Certificate object containing the name of the issuer
+
+ def set_issuer(self, key, subject=None, cert=None):
+ self.issuerKey = key
+ if subject:
+ # it's a mistake to use subject and cert params at the same time
+ assert(not cert)
+ if isinstance(subject, dict) or isinstance(subject, str):
+ req = OpenSSL.crypto.X509Req()
+ reqSubject = req.get_subject()
+ if isinstance(subject, dict):
+ for key in reqSubject.keys():
+ setattr(reqSubject, key, subject[key])
+ else:
+ setattr(reqSubject, "CN", subject)
+ subject = reqSubject
+ # subject is not valid once req is out of scope, so save req
+ self.issuerReq = req
+ if cert:
+ # if a cert was supplied, then get the subject from the cert
+ subject = cert.x509.get_subject()
+ assert(subject)
+ self.issuerSubject = subject
+
+ ##
+ # Get the issuer name
+
+ def get_issuer(self, which="CN"):
+ x = self.x509.get_issuer()
+ return getattr(x, which)
+
+ ##
+ # Set the subject name of the certificate
+
+ def set_subject(self, name):
+ req = OpenSSL.crypto.X509Req()
+ subj = req.get_subject()
+ if isinstance(name, dict):
+ for key in name.keys():
+ setattr(subj, key, name[key])
+ else:
+ setattr(subj, "CN", name)
+ self.x509.set_subject(subj)
+
+ ##
+ # Get the subject name of the certificate
+
+ def get_subject(self, which="CN"):
+ x = self.x509.get_subject()
+ return getattr(x, which)
+
+ ##
+ # Get a pretty-print subject name of the certificate
+ # let's try to make this a little more usable as is makes logs hairy
+ # FIXME: Consider adding 'urn:publicid' and 'uuid' back for GENI?
+ pretty_fields = ['email']
+
+ def filter_chunk(self, chunk):
+ for field in self.pretty_fields:
+ if field in chunk:
+ return " " + chunk
+
+ def pretty_cert(self):
+ message = "[Cert."
+ x = self.x509.get_subject()
+ ou = getattr(x, "OU")
+ if ou:
+ message += " OU: {}".format(ou)
+ cn = getattr(x, "CN")
+ if cn:
+ message += " CN: {}".format(cn)
+ data = self.get_data(field='subjectAltName')
+ if data:
+ message += " SubjectAltName:"
+ counter = 0
+ filtered = [self.filter_chunk(chunk) for chunk in data.split()]
+ message += " ".join([f for f in filtered if f])
+ omitted = len([f for f in filtered if not f])
+ if omitted:
+ message += "..+{} omitted".format(omitted)
+ message += "]"
+ return message
+
+ def pretty_chain(self):
+ message = "{}".format(self.x509.get_subject())
+ parent = self.parent
+ while parent:
+ message += "->{}".format(parent.x509.get_subject())
+ parent = parent.parent
+ return message
+
+ def pretty_name(self):
+ return self.get_filename() or self.pretty_chain()
+
+ ##
+ # Get the public key of the certificate.
+ #
+ # @param key Keypair object containing the public key
+
+ def set_pubkey(self, key):
+ assert(isinstance(key, Keypair))
+ self.x509.set_pubkey(key.get_openssl_pkey())
+
+ ##
+ # Get the public key of the certificate.
+ # It is returned in the form of a Keypair object.
+
+ def get_pubkey(self):
+ import M2Crypto
+ m2x509 = M2Crypto.X509.load_cert_string(self.save_to_string())
+ pkey = Keypair()
+ pkey.key = self.x509.get_pubkey()
+ pkey.m2key = m2x509.get_pubkey()
+ return pkey
+
+ def set_intermediate_ca(self, val):
+ return self.set_is_ca(val)
+
+ # Set whether this cert is for a CA.
+ # All signers and only signers should be CAs.
+ # The local member starts unset, letting us check that you only set it once
+ # @param val Boolean indicating whether this cert is for a CA
+ def set_is_ca(self, val):
+ if val is None:
+ return
+
+ if self.isCA is not None:
+ # Can't double set properties
+ raise Exception(
+ "Cannot set basicConstraints CA:?? more than once. "
+ "Was {}, trying to set as {}".format(self.isCA, val))
+
+ self.isCA = val
+ if val:
+ self.add_extension('basicConstraints', 1, 'CA:TRUE')
+ else:
+ self.add_extension('basicConstraints', 1, 'CA:FALSE')
+
+ ##
+ # Add an X509 extension to the certificate. Add_extension can only
+ # be called once for a particular extension name, due to
+ # limitations in the underlying library.
+ #
+ # @param name string containing name of extension
+ # @param value string containing value of the extension
+
+ def add_extension(self, name, critical, value):
+ oldExtVal = None
+ try:
+ oldExtVal = self.get_extension(name)
+ except:
+ # M2Crypto LookupError when the extension isn't there (yet)
+ pass
+
+ # This code limits you from adding the extension with the same value
+ # The method comment says you shouldn't do this with the same name
+ # But actually it (m2crypto) appears to allow you to do this.
+ if oldExtVal and oldExtVal == value:
+ # don't add this extension again
+ # just do nothing as here
+ return
+ # FIXME: What if they are trying to set with a different value?
+ # Is this ever OK? Or should we raise an exception?
+# elif oldExtVal:
+# raise "Cannot add extension {} which had val {} with new val {}"\
+# .format(name, oldExtVal, value)
+
+ ext = OpenSSL.crypto.X509Extension(name, critical, value)
+ self.x509.add_extensions([ext])
+
+ ##
+ # Get an X509 extension from the certificate
+
+ def get_extension(self, name):
+
+ import M2Crypto
+ if name is None:
+ return None
+
+ certstr = self.save_to_string()
+ if certstr is None or certstr == "":
+ return None
+ # pyOpenSSL does not have a way to get extensions
+ m2x509 = M2Crypto.X509.load_cert_string(certstr)
+ if m2x509 is None:
+ logger.warn("No cert loaded in get_extension")
+ return None
+ if m2x509.get_ext(name) is None:
+ return None
+ value = m2x509.get_ext(name).get_value()
+
+ return value
+
+ ##
+ # Set_data is a wrapper around add_extension. It stores the
+ # parameter str in the X509 subject_alt_name extension. Set_data
+ # can only be called once, due to limitations in the underlying
+ # library.
+
+ def set_data(self, string, field='subjectAltName'):
+ # pyOpenSSL only allows us to add extensions, so if we try to set the
+ # same extension more than once, it will not work
+ if field in self.data:
+ raise Exception("Cannot set {} more than once".format(field))
+ self.data[field] = string
+ self.add_extension(field, 0, string)
+
+ ##
+ # Return the data string that was previously set with set_data
+
+ def get_data(self, field='subjectAltName'):
+ if field in self.data:
+ return self.data[field]
+
+ try:
+ uri = self.get_extension(field)
+ self.data[field] = uri
+ except LookupError:
+ return None
+
+ return self.data[field]
+
+ ##
+ # Sign the certificate using the issuer private key and issuer subject
+ # previous set with set_issuer().
+
+ def sign(self):
+ logger.debug('certificate.sign')
+ assert self.x509 is not None
+ assert self.issuerSubject is not None
+ assert self.issuerKey is not None
+ self.x509.set_issuer(self.issuerSubject)
+ self.x509.sign(self.issuerKey.get_openssl_pkey(), self.digest)
##
# Verify the authenticity of a certificate.
# @param pkey is a Keypair object representing a public key. If Pkey
# did not sign the certificate, then an exception will be thrown.
- def verify(self, pkey):
- # pyOpenSSL does not have a way to verify signatures
- m2x509 = X509.load_cert_string(self.save_to_string())
- m2pkey = pkey.get_m2_pkey()
- # verify it
- return m2x509.verify(m2pkey)
-
- # XXX alternatively, if openssl has been patched, do the much simpler:
- # try:
- # self.cert.verify(pkey.get_openssl_key())
- # return 1
- # except:
- # return 0
-
- ##
- # Return True if pkey is identical to the public key that is contained in the certificate.
- # @param pkey Keypair object
-
- def is_pubkey(self, pkey):
- return self.get_pubkey().is_same(pkey)
-
- ##
- # Given a certificate cert, verify that this certificate was signed by the
- # public key contained in cert. Throw an exception otherwise.
- #
- # @param cert certificate object
-
- def is_signed_by_cert(self, cert):
- k = cert.get_pubkey()
- result = self.verify(k)
- return result
-
- ##
- # Set the parent certficiate.
- #
- # @param p certificate object.
-
- def set_parent(self, p):
+ def verify(self, pubkey):
+ import M2Crypto
+ # pyOpenSSL does not have a way to verify signatures
+ m2x509 = M2Crypto.X509.load_cert_string(self.save_to_string())
+ m2pubkey = pubkey.get_m2_pubkey()
+ # verify it
+ # https://www.openssl.org/docs/man1.1.0/crypto/X509_verify.html
+ # verify returns
+ # 1 if it checks out
+ # 0 if if does not
+ # -1 if it could not be checked 'for some reason'
+ m2result = m2x509.verify(m2pubkey)
+ result = m2result == 1
+ if debug_verify_chain:
+ logger.debug("Certificate.verify: <- {} (m2={}) ({} x {})"
+ .format(result, m2result,
+ self.pretty_cert(), m2pubkey))
+ return result
+
+ # XXX alternatively, if openssl has been patched, do the much simpler:
+ # try:
+ # self.x509.verify(pkey.get_openssl_key())
+ # return 1
+ # except:
+ # return 0
+
+ ##
+ # Return True if pkey is identical to the public key that is
+ # contained in the certificate.
+ # @param pkey Keypair object
+
+ def is_pubkey(self, pkey):
+ return self.get_pubkey().is_same(pkey)
+
+ ##
+ # Given a certificate cert, verify that this certificate was signed by the
+ # public key contained in cert. Throw an exception otherwise.
+ #
+ # @param cert certificate object
+
+ def is_signed_by_cert(self, cert):
+ logger.debug("Certificate.is_signed_by_cert -> invoking verify")
+ k = cert.get_pubkey()
+ result = self.verify(k)
+ return result
+
+ ##
+ # Set the parent certficiate.
+ #
+ # @param p certificate object.
+
+ def set_parent(self, p):
self.parent = p
- ##
- # Return the certificate object of the parent of this certificate.
+ ##
+ # Return the certificate object of the parent of this certificate.
- def get_parent(self):
+ def get_parent(self):
return self.parent
- ##
- # Verification examines a chain of certificates to ensure that each parent
- # signs the child, and that some certificate in the chain is signed by a
- # trusted certificate.
- #
- # Verification is a basic recursion: <pre>
- # if this_certificate was signed by trusted_certs:
- # return
- # else
- # return verify_chain(parent, trusted_certs)
- # </pre>
- #
- # At each recursion, the parent is tested to ensure that it did sign the
- # child. If a parent did not sign a child, then an exception is thrown. If
- # the bottom of the recursion is reached and the certificate does not match
- # a trusted root, then an exception is thrown.
- #
- # @param Trusted_certs is a list of certificates that are trusted.
- #
-
- def verify_chain(self, trusted_certs = None):
+ ##
+ # Verification examines a chain of certificates to ensure that each parent
+ # signs the child, and that some certificate in the chain is signed by a
+ # trusted certificate.
+ #
+ # Verification is a basic recursion: <pre>
+ # if this_certificate was signed by trusted_certs:
+ # return
+ # else
+ # return verify_chain(parent, trusted_certs)
+ # </pre>
+ #
+ # At each recursion, the parent is tested to ensure that it did sign the
+ # child. If a parent did not sign a child, then an exception is thrown. If
+ # the bottom of the recursion is reached and the certificate does not match
+ # a trusted root, then an exception is thrown.
+ # Also require that parents are CAs.
+ #
+ # @param Trusted_certs is a list of certificates that are trusted.
+ #
+
+ def verify_chain(self, trusted_certs=None):
# Verify a chain of certificates. Each certificate must be signed by
# the public key contained in it's parent. The chain is recursed
# until a certificate is found that is signed by a trusted root.
- # TODO: verify expiration time
+ logger.debug("Certificate.verify_chain {}".format(self.pretty_name()))
+ # verify expiration time
+ if self.x509.has_expired():
+ if debug_verify_chain:
+ logger.debug("verify_chain: NO, Certificate {} has expired"
+ .format(self.pretty_cert()))
+ raise CertExpired(self.pretty_cert(), "client cert")
# if this cert is signed by a trusted_cert, then we are set
- for trusted_cert in trusted_certs:
- # TODO: verify expiration of trusted_cert ?
+ for i, trusted_cert in enumerate(trusted_certs, 1):
+ logger.debug("Certificate.verify_chain - trying trusted #{} : {}"
+ .format(i, trusted_cert.pretty_name()))
if self.is_signed_by_cert(trusted_cert):
- #print self.get_subject(), "is signed by a root"
- return
+ # verify expiration of trusted_cert ?
+ if not trusted_cert.x509.has_expired():
+ if debug_verify_chain:
+ logger.debug("verify_chain: YES."
+ " Cert {} signed by trusted cert {}"
+ .format(self.pretty_name(),
+ trusted_cert.pretty_name()))
+ return trusted_cert
+ else:
+ if debug_verify_chain:
+ logger.debug("verify_chain: NO. Cert {} "
+ "is signed by trusted_cert {}, "
+ "but that signer is expired..."
+ .format(self.pretty_cert(),
+ trusted_cert.pretty_cert()))
+ raise CertExpired("{} signer trusted_cert {}"
+ .format(self.pretty_name(),
+ trusted_cert.pretty_name()))
+ else:
+ logger.debug("verify_chain: not a direct"
+ " descendant of a trusted root")
# if there is no parent, then no way to verify the chain
if not self.parent:
- #print self.get_subject(), "has no parent"
- raise CertMissingParent(self.get_subject())
+ if debug_verify_chain:
+ logger.debug("verify_chain: NO. {} has no parent "
+ "and issuer {} is not in {} trusted roots"
+ .format(self.pretty_name(), self.get_issuer(),
+ len(trusted_certs)))
+ raise CertMissingParent("{}: Issuer {} is not "
+ "one of the {} trusted roots, "
+ "and cert has no parent."
+ .format(self.pretty_name(),
+ self.get_issuer(),
+ len(trusted_certs)))
# if it wasn't signed by the parent...
if not self.is_signed_by_cert(self.parent):
- #print self.get_subject(), "is not signed by parent"
- return CertNotSignedByParent(self.get_subject())
+ if debug_verify_chain:
+ logger.debug("verify_chain: NO. {} is not signed by parent {}"
+ .format(self.pretty_name(),
+ self.parent.pretty_name()))
+ self.save_to_file("/tmp/xxx-capture.pem", save_parents=True)
+ raise CertNotSignedByParent("{}: Parent {}, issuer {}"
+ .format(self.pretty_name(),
+ self.parent.pretty_name(),
+ self.get_issuer()))
+
+ # Confirm that the parent is a CA. Only CAs can be trusted as
+ # signers.
+ # Note that trusted roots are not parents, so don't need to be
+ # CAs.
+ # Ugly - cert objects aren't parsed so we need to read the
+ # extension and hope there are no other basicConstraints
+ if not self.parent.isCA and not (
+ self.parent.get_extension('basicConstraints') == 'CA:TRUE'):
+ logger.warn("verify_chain: cert {}'s parent {} is not a CA"
+ .format(self.pretty_name(), self.parent.pretty_name()))
+ raise CertNotSignedByParent("{}: Parent {} not a CA"
+ .format(self.pretty_name(),
+ self.parent.pretty_name()))
# if the parent isn't verified...
+ if debug_verify_chain:
+ logger.debug("verify_chain: .. {}, -> verifying parent {}"
+ .format(self.pretty_name(),
+ self.parent.pretty_name()))
self.parent.verify_chain(trusted_certs)
return
+
+ # more introspection
+ def get_extensions(self):
+ import M2Crypto
+ # pyOpenSSL does not have a way to get extensions
+ triples = []
+ m2x509 = M2Crypto.X509.load_cert_string(self.save_to_string())
+ nb_extensions = m2x509.get_ext_count()
+ logger.debug("X509 had {} extensions".format(nb_extensions))
+ for i in range(nb_extensions):
+ ext = m2x509.get_ext_at(i)
+ triples.append(
+ (ext.get_name(), ext.get_value(), ext.get_critical(),))
+ return triples
+
+ def get_data_names(self):
+ return self.data.keys()
+
+ def get_all_datas(self):
+ triples = self.get_extensions()
+ for name in self.get_data_names():
+ triples.append((name, self.get_data(name), 'data',))
+ return triples
+
+ # only informative
+ def get_filename(self):
+ return getattr(self, 'filename', None)
+
+ def dump(self, *args, **kwargs):
+ print(self.dump_string(*args, **kwargs))
+
+ def dump_string(self, show_extensions=False):
+ result = ""
+ result += "CERTIFICATE for {}\n".format(self.pretty_cert())
+ result += "Issued by {}\n".format(self.get_issuer())
+ filename = self.get_filename()
+ if filename:
+ result += "Filename {}\n".format(filename)
+ if show_extensions:
+ all_datas = self.get_all_datas()
+ result += " has {} extensions/data attached".format(len(all_datas))
+ for n, v, c in all_datas:
+ if c == 'data':
+ result += " data: {}={}\n".format(n, v)
+ else:
+ result += " ext: {} (crit={})=<<<{}>>>\n".format(n, c, v)
+ return result