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