X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=sfa%2Ftrust%2Fcertificate.py;h=9552d1ff9834676077666555e36297bfeb58adcb;hb=fd395e1944dcd49f10a4d5b27ce4983ad389fb96;hp=6f3ecc6268f25c222fc77d6270b6b9f47e4d7c81;hpb=ecc85e0b923922cf7117d29b380f5284edb88f21;p=sfa.git diff --git a/sfa/trust/certificate.py b/sfa/trust/certificate.py index 6f3ecc62..9552d1ff 100644 --- a/sfa/trust/certificate.py +++ b/sfa/trust/certificate.py @@ -1,4 +1,4 @@ -#---------------------------------------------------------------------- +# ---------------------------------------------------------------------- # Copyright (c) 2008 Board of Trustees, Princeton University # # Permission is hereby granted, free of charge, to any person obtaining @@ -11,17 +11,17 @@ # 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 +# 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 @@ -35,6 +35,16 @@ ## # +# 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 @@ -43,15 +53,18 @@ import tempfile import base64 from tempfile import mkstemp -from OpenSSL import crypto -import M2Crypto -from M2Crypto import X509 +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.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 +debug_verify_chain = True glo_passphrase_callback = None @@ -65,6 +78,7 @@ glo_passphrase_callback = None # # The callback should return a string containing the passphrase. + def set_passphrase_callback(callback_func): global glo_passphrase_callback @@ -73,24 +87,29 @@ def set_passphrase_callback(callback_func): ## # Sets a fixed passphrase. + def set_passphrase(passphrase): - set_passphrase_callback( lambda k,s,x: 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)) + OpenSSL.crypto.load_privatekey( + OpenSSL.crypto.FILETYPE_PEM, string, (lambda x: passphrase)) return True except: return False + def convert_public_key(key): 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 if "ssh-dss" in key: @@ -108,7 +127,8 @@ def convert_public_key(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): - raise Exception("keyconvert: generated certificate not found. keyconvert may have failed.") + raise Exception( + "generated certificate not found. keyconvert may have failed.") k = Keypair() try: @@ -129,6 +149,7 @@ def convert_public_key(key): # 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) @@ -137,8 +158,8 @@ class Keypair: # 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 + # @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: @@ -149,11 +170,12 @@ class Keypair: self.load_from_file(filename) ## - # Create a RSA public/private key pair and store it inside the keypair object + # 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, 2048) + self.key = OpenSSL.crypto.PKey() + self.key.generate_key(OpenSSL.crypto.TYPE_RSA, 2048) ## # Save the private key to a file @@ -161,33 +183,40 @@ class Keypair: def save_to_file(self, filename): open(filename, 'w').write(self.as_pem()) - self.filename=filename + self.filename = filename ## - # Load the private key from a file. Implicity the private key includes the public key. + # Load the private key from a file. Implicity the private key includes the + # public key. def load_from_file(self, filename): - self.filename=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. + # 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 = crypto.load_privatekey( - crypto.FILETYPE_PEM, string, functools.partial(glo_passphrase_callback, self, string)) + 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)) + string, functools.partial(glo_passphrase_callback, + self, string)) else: - self.key = crypto.load_privatekey(crypto.FILETYPE_PEM, string) + 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() @@ -195,7 +224,8 @@ class Keypair: # 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) + 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) @@ -213,11 +243,12 @@ class Keypair: # convert the m2 x509 cert to a pyopenssl x509 m2pem = m2x509.as_pem() - pyx509 = crypto.load_certificate(crypto.FILETYPE_PEM, m2pem) + 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 + self.filename = filename ## # Load the public key from a string. No private key is loaded. @@ -233,12 +264,14 @@ class Keypair: # Return the private key in PEM format. def as_pem(self): - return crypto.dump_privatekey(crypto.FILETYPE_PEM, self.key) + 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 @@ -269,6 +302,7 @@ class Keypair: 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) @@ -279,16 +313,17 @@ class Keypair: # only informative def get_filename(self): - return getattr(self,'filename',None) + return getattr(self, 'filename', None) - def dump (self, *args, **kwargs): + def dump(self, *args, **kwargs): print(self.dump_string(*args, **kwargs)) - def dump_string (self): - result="" - result += "KEYPAIR: pubkey=%40s..."%self.get_pubkey_string() - filename=self.get_filename() - if filename: result += "Filename %s\n"%filename + 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 ## @@ -303,6 +338,7 @@ class Keypair: # 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 = "sha256" @@ -310,9 +346,9 @@ class Certificate: # issuerKey = None # issuerSubject = None # parent = None - isCA = None # will be a boolean once set + isCA = None # will be a boolean once set - separator="-----parent-----" + separator = "-----parent-----" ## # Create a certificate object. @@ -325,7 +361,8 @@ class Certificate: # @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): + 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 @@ -343,19 +380,19 @@ class Certificate: self.load_from_file(filename) # Set the CA bit if a value was supplied - if isCA != None: + 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 = crypto.X509() + 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 - + 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 @@ -369,38 +406,43 @@ class Certificate: 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) + # 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") + logger.warning("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%s\n-----END CERTIFICATE-----' % string + 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 + # 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) + string.count(Certificate.separator) == 0: + parts = string.split('-----END CERTIFICATE-----', 1) parts[0] += '-----END CERTIFICATE-----' else: parts = string.split(Certificate.separator, 1) - self.x509 = crypto.load_certificate(crypto.FILETYPE_PEM, parts[0]) + 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: %s" % string) + logger.warning( + "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 @@ -415,25 +457,30 @@ class Certificate: file = open(filename) string = file.read() self.load_from_string(string) - self.filename=filename + self.filename = filename ## # Save the certificate to a string. # - # @param save_parents If save_parents==True, then also save the parent certificates. + # @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") + logger.warning("None cert in certificate.save_to_string") return "" - string = crypto.dump_certificate(crypto.FILETYPE_PEM, self.x509) + 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. + # @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) @@ -441,13 +488,16 @@ class Certificate: f = filep else: f = open(filename, 'w') + if PY3 and isinstance(string, bytes): + string = string.decode() f.write(string) f.close() - self.filename=filename + 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. + # @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") @@ -458,7 +508,8 @@ class Certificate: # 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 + # @param cert (optional) + # Certificate object containing the name of the issuer def set_issuer(self, key, subject=None, cert=None): self.issuerKey = key @@ -466,9 +517,9 @@ class Certificate: # 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() + req = OpenSSL.crypto.X509Req() reqSubject = req.get_subject() - if (isinstance(subject, dict)): + if isinstance(subject, dict): for key in reqSubject.keys(): setattr(reqSubject, key, subject[key]) else: @@ -493,9 +544,9 @@ class Certificate: # Set the subject name of the certificate def set_subject(self, name): - req = crypto.X509Req() + req = OpenSSL.crypto.X509Req() subj = req.get_subject() - if (isinstance(name, dict)): + if isinstance(name, dict): for key in name.keys(): setattr(subj, key, name[key]) else: @@ -514,30 +565,44 @@ class 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 + return " " + chunk def pretty_cert(self): message = "[Cert." x = self.x509.get_subject() ou = getattr(x, "OU") - if ou: message += " OU: {}".format(ou) + if ou: + message += " OU: {}".format(ou) cn = getattr(x, "CN") - if cn: message += " CN: {}".format(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]) + 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. # @@ -552,7 +617,8 @@ class Certificate: # It is returned in the form of a Keypair object. def get_pubkey(self): - m2x509 = X509.load_cert_string(self.save_to_string()) + 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() @@ -561,16 +627,19 @@ class Certificate: 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. + # 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: + if self.isCA is not 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)) + raise Exception( + "Cannot set basicConstraints CA:?? more than once. " + "Was {}, trying to set as {}".format(self.isCA, val)) self.isCA = val if val: @@ -578,12 +647,10 @@ class Certificate: 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. + # 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 @@ -606,9 +673,10 @@ class Certificate: # 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) +# raise "Cannot add extension {} which had val {} with new val {}"\ +# .format(name, oldExtVal, value) - ext = crypto.X509Extension (name, critical, value) + ext = OpenSSL.crypto.X509Extension(name, critical, value) self.x509.add_extensions([ext]) ## @@ -616,6 +684,7 @@ class Certificate: def get_extension(self, name): + import M2Crypto if name is None: return None @@ -623,9 +692,9 @@ class Certificate: if certstr is None or certstr == "": return None # pyOpenSSL does not have a way to get extensions - m2x509 = X509.load_cert_string(certstr) + m2x509 = M2Crypto.X509.load_cert_string(certstr) if m2x509 is None: - logger.warn("No cert loaded in get_extension") + logger.warning("No cert loaded in get_extension") return None if m2x509.get_ext(name) is None: return None @@ -634,23 +703,24 @@ class Certificate: 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. + # 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, field='subjectAltName'): + 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 self.data.has_key(field): - raise "Cannot set ", field, " more than once" - self.data[field] = str - self.add_extension(field, 0, str) + 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 self.data.has_key(field): + if field in self.data: return self.data[field] try: @@ -662,13 +732,14 @@ class Certificate: return self.data[field] ## - # Sign the certificate using the issuer private key and issuer subject previous set with set_issuer(). + # 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 != None - assert self.issuerSubject != None - assert self.issuerKey != None + 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) @@ -678,13 +749,23 @@ class Certificate: # did not sign the certificate, then an exception will be thrown. def verify(self, pubkey): + import M2Crypto # pyOpenSSL does not have a way to verify signatures - m2x509 = X509.load_cert_string(self.save_to_string()) + m2x509 = M2Crypto.X509.load_cert_string(self.save_to_string()) m2pubkey = pubkey.get_m2_pubkey() # verify it - # verify returns -1 or 0 on failure depending on how serious the - # error conditions are - return m2x509.verify(m2pubkey) == 1 + # 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: @@ -694,7 +775,8 @@ class Certificate: # return 0 ## - # Return True if pkey is identical to the public key that is contained in the certificate. + # 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): @@ -708,6 +790,9 @@ class Certificate: def is_signed_by_cert(self, cert): k = cert.get_pubkey() + logger.debug("Certificate.is_signed_by_cert -> verify on {}\n" + "with pubkey {}" + .format(self, k)) result = self.verify(k) return result @@ -746,52 +831,71 @@ class Certificate: # @param Trusted_certs is a list of certificates that are trusted. # - def verify_chain(self, trusted_certs = None): + 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. + 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 %s has expired" % self.pretty_cert()) + 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: + 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): # verify expiration of trusted_cert ? if not trusted_cert.x509.has_expired(): if debug_verify_chain: - logger.debug("verify_chain: YES. Cert %s signed by trusted cert %s"%( - self.pretty_cert(), trusted_cert.pretty_cert())) + 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 %s is signed by trusted_cert %s, but that signer is expired..."%( - self.pretty_cert(),trusted_cert.pretty_cert())) - raise CertExpired(self.pretty_cert()," signer trusted_cert %s"%trusted_cert.pretty_cert()) + 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 trusted root #{}".format(i)) # if there is no parent, then no way to verify the chain if not self.parent: if debug_verify_chain: - logger.debug("verify_chain: NO. %s has no parent and issuer %s is not in %d trusted roots"%\ - (self.pretty_cert(), self.get_issuer(), len(trusted_certs))) - raise CertMissingParent(self.pretty_cert() + \ - ": Issuer %s is not one of the %d trusted roots, and cert has no parent." %\ - (self.get_issuer(), len(trusted_certs))) + 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): if debug_verify_chain: - logger.debug("verify_chain: NO. %s is not signed by parent %s, but by %s"%\ - (self.pretty_cert(), - self.parent.pretty_cert(), - self.get_issuer())) - raise CertNotSignedByParent("%s: Parent %s, issuer %s"\ - % (self.pretty_cert(), - self.parent.pretty_cert(), - self.get_issuer())) + 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. @@ -799,60 +903,66 @@ class Certificate: # 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.pretty_cert(), self.parent.pretty_cert())) - raise CertNotSignedByParent("%s: Parent %s not a CA" % (self.pretty_cert(), - self.parent.pretty_cert())) + if not self.parent.isCA and not ( + self.parent.get_extension('basicConstraints') == 'CA:TRUE'): + logger.warning("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: .. %s, -> verifying parent %s"%\ - (self.pretty_cert(),self.parent.pretty_cert())) + logger.debug("verify_chain: .. {}, -> verifying parent {}" + .format(self.pretty_name(), + self.parent.pretty_name())) self.parent.verify_chain(trusted_certs) return - ### more introspection + # more introspection def get_extensions(self): + import M2Crypto # pyOpenSSL does not have a way to get extensions triples = [] - m2x509 = X509.load_cert_string(self.save_to_string()) + m2x509 = M2Crypto.X509.load_cert_string(self.save_to_string()) nb_extensions = m2x509.get_ext_count() - logger.debug("X509 had %d extensions"%nb_extensions) + 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(),) ) + 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): + def get_all_datas(self): triples = self.get_extensions() for name in self.get_data_names(): - triples.append( (name,self.get_data(name),'data',) ) + triples.append((name, self.get_data(name), 'data',)) return triples # only informative def get_filename(self): - return getattr(self,'filename',None) + return getattr(self, 'filename', None) - def dump (self, *args, **kwargs): + def dump(self, *args, **kwargs): print(self.dump_string(*args, **kwargs)) - def dump_string (self,show_extensions=False): + def dump_string(self, show_extensions=False): result = "" - result += "CERTIFICATE for %s\n"%self.pretty_cert() - result += "Issued by %s\n"%self.get_issuer() - filename=self.get_filename() - if filename: result += "Filename %s\n"%filename + 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 %d extensions/data attached"%len(all_datas) - for (n, v, c) in all_datas: - if c=='data': - result += " data: %s=%s\n"%(n,v) + 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: %s (crit=%s)=<<<%s>>>\n"%(n,c,v) + result += " ext: {} (crit={})=<<<{}>>>\n".format(n, c, v) return result