##
#
+import functools
import os
import tempfile
import base64
-import traceback
from tempfile import mkstemp
from OpenSSL import crypto
import M2Crypto
from M2Crypto import X509
-from sfa.util.sfalogging import sfa_logger
-from sfa.util.xrn import urn_to_hrn
-from sfa.util.faults import *
+from sfa.util.faults import CertExpired, CertMissingParent, CertNotSignedByParent
+from sfa.util.sfalogging import logger
+
+glo_passphrase_callback = None
+
+##
+# A global callback msy 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:
+ crypto.load_privatekey(crypto.FILETYPE_PEM, string, (lambda x: passphrase))
+ return True
+ except:
+ return False
def convert_public_key(key):
keyconvert_path = "/usr/bin/keyconvert.py"
# we can only convert rsa keys
if "ssh-dss" in key:
- return None
+ raise Exception, "keyconvert: dss keys are not supported"
(ssh_f, ssh_fn) = tempfile.mkstemp()
ssl_fn = tempfile.mktemp()
# that it can be expected to see why it failed.
# TODO: for production, cleanup the temporary files
if not os.path.exists(ssl_fn):
- return None
+ raise Exception, "keyconvert: generated certificate not found. keyconvert may have failed."
k = Keypair()
try:
k.load_pubkey_from_file(ssl_fn)
+ return k
except:
- sfa_logger().log_exc("convert_public_key caught exception")
- k = None
+ 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)
- # remove the temporary files
- os.remove(ssh_fn)
- os.remove(ssl_fn)
-
- return k
##
# Public-private key pairs are implemented by the Keypair class.
# 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)
- self.filename=filename
##
# 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)
+ if glo_passphrase_callback:
+ self.key = crypto.load_privatekey(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 = 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.
filename=self.get_filename()
if filename: result += "Filename %s\n"%filename
return result
-
+
##
# The certificate class implements a general purpose X509 certificate, making
# use of the appropriate pyOpenSSL or M2Crypto abstractions. It also adds
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, create=False, subject=None, string=None, filename=None, intermediate=None):
+ def __init__(self, lifeDays=1825, create=False, subject=None, string=None, filename=None, isCA=None):
self.data = {}
if create or subject:
- self.create()
+ self.create(lifeDays)
if subject:
self.set_subject(subject)
if string:
if filename:
self.load_from_file(filename)
- if intermediate:
- self.set_intermediate_ca(intermediate)
+ # Set the CA bit if a value was supplied
+ if isCA != None:
+ self.set_is_ca(isCA)
- ##
# Create a blank X509 certificate and store it in this object.
- def create(self):
+ def create(self, lifeDays=1825):
self.cert = crypto.X509()
+ # FIXME: Use different serial #s
self.cert.set_serial_number(3)
- self.cert.gmtime_adj_notBefore(0)
- self.cert.gmtime_adj_notAfter(60*60*24*365*5) # five years
- self.cert.set_version(2) # x509v3 so it can have extensions
+ self.cert.gmtime_adj_notBefore(0) # 0 means now
+ self.cert.gmtime_adj_notAfter(lifeDays*60*60*24) # five years is default
+ self.cert.set_version(2) # x509v3 so it can have extensions
##
else:
setattr(subj, "CN", name)
self.cert.set_subject(subj)
+
##
# Get the subject name of the certificate
x = self.cert.get_subject()
return getattr(x, which)
+ ##
+ # Get a pretty-print subject name of the certificate
+
+ def get_printable_subject(self):
+ x = self.cert.get_subject()
+ return "[ OU: %s, CN: %s, SubjectAltName: %s ]" % (getattr(x, "OU"), getattr(x, "CN"), self.get_data())
+
##
# Get the public key of the certificate.
#
return pkey
def set_intermediate_ca(self, val):
- self.intermediate = 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 != None:
+ # Can't double set properties
+ raise Exception, "Cannot set basicConstraints CA:?? more than once. Was %s, trying to set as %s" % (self.isCA, val)
+
+ self.isCA = val
if val:
self.add_extension('basicConstraints', 1, 'CA:TRUE')
+ else:
+ self.add_extension('basicConstraints', 1, 'CA:FALSE')
# @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 %s which had val %s with new val %s" % (name, oldExtVal, value)
+
ext = crypto.X509Extension (name, critical, value)
self.cert.add_extensions([ext])
# 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
##
# Sign the certificate using the issuer private key and issuer subject previous set with set_issuer().
def sign(self):
- sfa_logger().debug('certificate.sign')
+ logger.debug('certificate.sign')
assert self.cert != None
assert self.issuerSubject != None
assert self.issuerKey != None
# 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.
#
# verify expiration time
if self.cert.has_expired():
- sfa_logger().debug("verify_chain: NO our certificate has expired")
- raise CertExpired(self.get_subject(), "client cert")
-
+ logger.debug("verify_chain: NO, Certificate %s has expired" % self.get_printable_subject())
+ raise CertExpired(self.get_printable_subject(), "client cert")
+
# if this cert is signed by a trusted_cert, then we are set
for trusted_cert in trusted_certs:
if self.is_signed_by_cert(trusted_cert):
# verify expiration of trusted_cert ?
if not trusted_cert.cert.has_expired():
- sfa_logger().debug("verify_chain: YES cert %s signed by trusted cert %s"%(
- self.get_subject(), trusted_cert.get_subject()))
+ logger.debug("verify_chain: YES. Cert %s signed by trusted cert %s"%(
+ self.get_printable_subject(), trusted_cert.get_printable_subject()))
return trusted_cert
else:
- sfa_logger().debug("verify_chain: NO cert %s is signed by trusted_cert %s, but this is expired..."%(
- self.get_subject(),trusted_cert.get_subject()))
- raise CertExpired(self.get_subject(),"trusted_cert %s"%trusted_cert.get_subject())
+ logger.debug("verify_chain: NO. Cert %s is signed by trusted_cert %s, but that signer is expired..."%(
+ self.get_printable_subject(),trusted_cert.get_printable_subject()))
+ raise CertExpired(self.get_printable_subject()," signer trusted_cert %s"%trusted_cert.get_printable_subject())
# if there is no parent, then no way to verify the chain
if not self.parent:
- sfa_logger().debug("verify_chain: NO %s has no parent and is not in trusted roots"%self.get_subject())
- raise CertMissingParent(self.get_subject())
+ 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)))
+ raise CertMissingParent(self.get_printable_subject() + ": Issuer %s not trusted by any of %d trusted roots, and cert has no parent." % (self.get_issuer(), len(trusted_certs)))
# if it wasn't signed by the parent...
if not self.is_signed_by_cert(self.parent):
- sfa_logger().debug("verify_chain: NO %s is not signed by parent"%self.get_subject())
- return CertNotSignedByParent(self.get_subject())
+ logger.debug("verify_chain: NO. %s is not signed by parent %s, but by %s"%\
+ (self.get_printable_subject(),
+ self.parent.get_printable_subject(),
+ self.get_issuer()))
+ raise CertNotSignedByParent("%s: Parent %s, issuer %s"\
+ % (self.get_printable_subject(),
+ self.parent.get_printable_subject(),
+ 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's parent %s is not a CA" % \
+ (self.get_printable_subject(), self.parent.get_printable_subject()))
+ raise CertNotSignedByParent("%s: Parent %s not a CA" % (self.get_printable_subject(),
+ self.parent.get_printable_subject()))
# if the parent isn't verified...
- sfa_logger().debug("verify_chain: .. %s, -> verifying parent %s"%(self.get_subject(),self.parent.get_subject()))
+ logger.debug("verify_chain: .. %s, -> verifying parent %s"%\
+ (self.get_printable_subject(),self.parent.get_printable_subject()))
self.parent.verify_chain(trusted_certs)
return
triples=[]
m2x509 = X509.load_cert_string(self.save_to_string())
nb_extensions=m2x509.get_ext_count()
- sfa_logger().debug("X509 had %d extensions"%nb_extensions)
+ logger.debug("X509 had %d extensions"%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(),) )
def get_all_datas (self):
triples=self.get_extensions()
- for name in self.get_data_names():
+ for name in self.get_data_names():
triples.append( (name,self.get_data(name),'data',) )
return triples
def dump_string (self,show_extensions=False):
result = ""
- result += "CERTIFICATE for %s\n"%self.get_subject()
+ result += "CERTIFICATE for %s\n"%self.get_printable_subject()
result += "Issued by %s\n"%self.get_issuer()
filename=self.get_filename()
if filename: result += "Filename %s\n"%filename