# ---------------------------------------------------------------------- # 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 # 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. ## # # 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 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 = True 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 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 {}".format(keyconvert_path)) # we can only convert rsa keys if "ssh-dss" in key: raise Exception("keyconvert: dss keys are not supported") (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): raise Exception( "generated certificate not found. keyconvert may have failed.") k = Keypair() try: k.load_pubkey_from_file(ssl_fn) return k except: 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 = 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 # 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 = "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.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{}\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.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 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.warning("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.warning("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, 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): 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 ## # 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:
    #     if this_certificate was signed by trusted_certs:
    #         return
    #     else
    #         return verify_chain(parent, trusted_certs)
    # 
# # 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. 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 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 {} 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 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. {} 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. {} 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.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: .. {}, -> 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