X-Git-Url: http://git.onelab.eu/?p=sfa.git;a=blobdiff_plain;f=sfa%2Ftrust%2Fcredential.py;h=b957fadd8b6e4e92f8894bccf926987bd2384dbc;hp=ecdd3bdc7761c43537adc4e37ccafd58d68e5fac;hb=a89ccd803a21501565e4f4432293a907f168b972;hpb=8cbccf66e8c89243e1d55c0e71841cebb6c98006 diff --git a/sfa/trust/credential.py b/sfa/trust/credential.py index ecdd3bdc..b957fadd 100644 --- a/sfa/trust/credential.py +++ b/sfa/trust/credential.py @@ -1,4 +1,4 @@ -#---------------------------------------------------------------------- +# ---------------------------------------------------------------------- # Copyright (c) 2008 Board of Trustees, Princeton University # # Permission is hereby granted, free of charge, to any person obtaining @@ -19,11 +19,12 @@ # 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. -#---------------------------------------------------------------------- +# ---------------------------------------------------------------------- ## # Implements SFA Credentials # -# Credentials are signed XML files that assign a subject gid privileges to an object gid +# Credentials are signed XML files that assign a subject gid +# privileges to an object gid ## from __future__ import print_function @@ -37,22 +38,24 @@ from xml.dom.minidom import Document, parseString from sfa.util.py23 import PY3, StringType, StringIO -HAVELXML = False -try: - from lxml import etree - HAVELXML = True -except: - pass - from xml.parsers.expat import ExpatError -from sfa.util.faults import CredentialNotVerifiable, ChildRightsNotSubsetOfParent +from sfa.util.faults import (CredentialNotVerifiable, + ChildRightsNotSubsetOfParent) from sfa.util.sfalogging import logger from sfa.util.sfatime import utcparse, SFATIME_FORMAT from sfa.trust.rights import Right, Rights, determine_rights from sfa.trust.gid import GID from sfa.util.xrn import urn_to_hrn, hrn_authfor_hrn +HAVELXML = False +try: + from lxml import etree + HAVELXML = True +except: + pass + + # 31 days, in seconds DEFAULT_CREDENTIAL_LIFETIME = 86400 * 31 @@ -191,7 +194,8 @@ class Signature(object): if len(cert.childNodes) > 0: szgid = cert.childNodes[0].nodeValue szgid = szgid.strip() - szgid = "-----BEGIN CERTIFICATE-----\n{}\n-----END CERTIFICATE-----".format( + szgid = "-----BEGIN CERTIFICATE-----\n"\ + "{}\n-----END CERTIFICATE-----".format( szgid) if gids is None: gids = szgid @@ -209,8 +213,8 @@ class Signature(object): # A credential provides a caller gid with privileges to an object gid. # A signed credential is signed by the object's authority. # -# Credentials are encoded in one of two ways. -# The legacy style (now unsupported) places it in the subjectAltName of an X509 certificate. +# Credentials are encoded in one of two ways. The legacy style (now +# unsupported) places it in the subjectAltName of an X509 certificate. # The new credentials are placed in signed XML. # # WARNING: @@ -250,11 +254,13 @@ class Credential(object): # Create a Credential object # # @param create If true, create a blank x509 certificate - # @param subject If subject!=None, create an x509 cert with the subject name + # @param subject If subject!=None, + # create an x509 cert with the subject name # @param string If string!=None, load the credential from the string # @param filename If filename!=None, load the credential from the file # FIXME: create and subject are ignored! - def __init__(self, create=False, subject=None, string=None, filename=None, cred=None): + def __init__(self, create=False, subject=None, string=None, + filename=None, cred=None): self.gidCaller = None self.gidObject = None self.expiration = None @@ -289,7 +295,9 @@ class Credential(object): # if this is a legacy credential, write error and bail out if isinstance(str, StringType) and str.strip().startswith("-----"): logger.error( - "Legacy credentials not supported any more - giving up with {}...".format(str[:10])) + "Legacy credentials not supported any more " + "- giving up with {}..." + .format(str[:10])) return else: self.xml = str @@ -315,7 +323,8 @@ class Credential(object): break if not Credential.xmlsec1_path: logger.error( - "Could not locate required binary 'xmlsec1' - SFA will be unable to sign stuff !!") + "Could not locate required binary 'xmlsec1' -" + "SFA will be unable to sign stuff !!") return Credential.xmlsec1_path def get_subject(self): @@ -339,7 +348,8 @@ class Credential(object): caller = self.gidCaller.pretty_cert() exp = self.get_expiration() # Summarize the rights too? The issuer? - return "[Cred. for {caller} rights on {obj} until {exp} ]".format(**locals()) + return "[Cred. for {caller} rights on {obj} until {exp} ]"\ + .format(**locals()) def get_signature(self): if not self.signature: @@ -398,8 +408,9 @@ class Credential(object): self.decode() return self.gidObject - ## - # Expiration: an absolute UTC time of expiration (as either an int or string or datetime) + # + # Expiration: an absolute UTC time of expiration (as either an int + # or string or datetime) # def set_expiration(self, expiration): expiration_datetime = utcparse(expiration) @@ -407,7 +418,8 @@ class Credential(object): self.expiration = expiration_datetime else: logger.error( - "unexpected input {} in Credential.set_expiration".format(expiration)) + "unexpected input {} in Credential.set_expiration" + .format(expiration)) ## # get the lifetime of the credential (always in datetime format) @@ -422,7 +434,8 @@ class Credential(object): ## # set the privileges # - # @param privs either a comma-separated list of privileges of a Rights object + # @param privs either a comma-separated list of privileges of a + # Rights object def set_privileges(self, privs): if isinstance(privs, str): @@ -442,7 +455,8 @@ class Credential(object): # determine whether the credential allows a particular operation to be # performed # - # @param op_name string specifying name of operation ("lookup", "update", etc) + # @param op_name string specifying name of operation + # ("lookup", "update", etc) def can_perform(self, op_name): rights = self.get_privileges() @@ -476,14 +490,20 @@ class Credential(object): "xmlns:xsi", "http://www.w3.org/2001/XMLSchema-instance") # FIXME: See v2 schema at # www.geni.net/resources/credential/2/credential.xsd - signed_cred.setAttribute("xsi:noNamespaceSchemaLocation", - "http://www.planet-lab.org/resources/sfa/credential.xsd") signed_cred.setAttribute( - "xsi:schemaLocation", "http://www.planet-lab.org/resources/sfa/ext/policy/1 http://www.planet-lab.org/resources/sfa/ext/policy/1/policy.xsd") + "xsi:noNamespaceSchemaLocation", + "http://www.planet-lab.org/resources/sfa/credential.xsd") + signed_cred.setAttribute( + "xsi:schemaLocation", + "http://www.planet-lab.org/resources/sfa/ext/policy/1 " + "http://www.planet-lab.org/resources/sfa/ext/policy/1/policy.xsd") # PG says for those last 2: - # signed_cred.setAttribute("xsi:noNamespaceSchemaLocation", "http://www.protogeni.net/resources/credential/credential.xsd") - # signed_cred.setAttribute("xsi:schemaLocation", "http://www.protogeni.net/resources/credential/ext/policy/1 http://www.protogeni.net/resources/credential/ext/policy/1/policy.xsd") + # signed_cred.setAttribute("xsi:noNamespaceSchemaLocation", + # "http://www.protogeni.net/resources/credential/credential.xsd") + # signed_cred.setAttribute("xsi:schemaLocation", + # "http://www.protogeni.net/resources/credential/ext/policy/1 " + # "http://www.protogeni.net/resources/credential/ext/policy/1/policy.xsd") doc.appendChild(signed_cred) @@ -504,7 +524,8 @@ class Credential(object): self.set_expiration(datetime.datetime.utcnow( ) + datetime.timedelta(seconds=DEFAULT_CREDENTIAL_LIFETIME)) self.expiration = self.expiration.replace(microsecond=0) - if self.expiration.tzinfo is not None and self.expiration.tzinfo.utcoffset(self.expiration) is not None: + if self.expiration.tzinfo is not None \ + and self.expiration.tzinfo.utcoffset(self.expiration) is not None: # TZ aware. Make sure it is UTC - by Aaron Helsinger self.expiration = self.expiration.astimezone(tz.tzutc()) append_sub(doc, cred, "expires", @@ -527,14 +548,19 @@ class Credential(object): # If the root node is a signed-credential (it should be), then # get all its attributes and attach those to our signed_cred # node. - # Specifically, PG and PLadd attributes for namespaces (which is reasonable), + # Specifically, PG and PL add attributes for namespaces + # (which is reasonable), # and we need to include those again here or else their signature # no longer matches on the credential. # We expect three of these, but here we copy them all: - # signed_cred.setAttribute("xmlns:xsi", "http://www.w3.org/2001/XMLSchema-instance") + # signed_cred.setAttribute("xmlns:xsi", + # "http://www.w3.org/2001/XMLSchema-instance") # and from PG (PL is equivalent, as shown above): - # signed_cred.setAttribute("xsi:noNamespaceSchemaLocation", "http://www.protogeni.net/resources/credential/credential.xsd") - # signed_cred.setAttribute("xsi:schemaLocation", "http://www.protogeni.net/resources/credential/ext/policy/1 http://www.protogeni.net/resources/credential/ext/policy/1/policy.xsd") + # signed_cred.setAttribute("xsi:noNamespaceSchemaLocation", + # "http://www.protogeni.net/resources/credential/credential.xsd") + # signed_cred.setAttribute("xsi:schemaLocation", + # "http://www.protogeni.net/resources/credential/ext/policy/1 " + # "http://www.protogeni.net/resources/credential/ext/policy/1/policy.xsd") # HOWEVER! # PL now also declares these, with different URLs, so @@ -556,7 +582,8 @@ class Credential(object): # the contents of the schemas are the same, # or something else, but it seems odd. And this works. parentRoot = sdoc.documentElement - if parentRoot.tagName == "signed-credential" and parentRoot.hasAttributes(): + if parentRoot.tagName == "signed-credential" and \ + parentRoot.hasAttributes(): for attrIx in range(0, parentRoot.attributes.length): attr = parentRoot.attributes.item(attrIx) # returns the old attribute of same name that was @@ -568,10 +595,14 @@ class Credential(object): if oldAttr and oldAttr.value != attr.value: msg = "Delegating cred from owner {} to {} over {}:\n" "- Replaced attribute {} value '{}' with '{}'"\ - .format(self.parent.gidCaller.get_urn(), self.gidCaller.get_urn(), - self.gidObject.get_urn(), oldAttr.name, oldAttr.value, attr.value) + .format(self.parent.gidCaller.get_urn(), + self.gidCaller.get_urn(), + self.gidObject.get_urn(), + oldAttr.name, oldAttr.value, attr.value) logger.warn(msg) - #raise CredentialNotVerifiable("Can't encode new valid delegated credential: {}".format(msg)) + # raise CredentialNotVerifiable( + # "Can't encode new valid delegated credential: {}" + # .format(msg)) p_cred = doc.importNode( sdoc.getElementsByTagName("credential")[0], True) @@ -711,7 +742,8 @@ class Credential(object): if not xmlsec1: raise Exception("Could not locate required 'xmlsec1' program") command = '{} --sign --node-id "{}" --privkey-pem {},{} {}' \ - .format(xmlsec1, ref, self.issuer_privkey, ",".join(gid_files), filename) + .format(xmlsec1, ref, self.issuer_privkey, + ",".join(gid_files), filename) signed = os.popen(command).read() os.remove(filename) @@ -773,7 +805,8 @@ class Credential(object): kind = getTextNode(priv, "name") deleg = str2bool(getTextNode(priv, "can_delegate")) if kind == '*': - # Convert * into the default privileges for the credential's type + # Convert * into the default privileges + # for the credential's type # Each inherits the delegatability from the * above _, type = urn_to_hrn(self.gidObject.get_urn()) rl = determine_rights(type, self.gidObject.get_urn()) @@ -806,11 +839,12 @@ class Credential(object): ## # Verify # trusted_certs: A list of trusted GID filenames (not GID objects!) - # Chaining is not supported within the GIDs by xmlsec1. + # Chaining is not supported within the GIDs by xmlsec1. # # trusted_certs_required: Should usually be true. Set False means an - # empty list of trusted_certs would still let this method pass. - # It just skips xmlsec1 verification et al. Only used by some utils + # empty list of trusted_certs would still let this method pass. + # It just skips xmlsec1 verification et al. + # Only used by some utils # # Verify that: # . All of the signatures are valid and that the issuers trace back @@ -824,7 +858,8 @@ class Credential(object): # # -- For Delegates (credentials with parents) # . The privileges must be a subset of the parent credentials - # . The privileges must have "can_delegate" set for each delegated privilege + # . The privileges must have "can_delegate" + # set for each delegated privilege # . The target gid must be the same between child and parents # . The expiry time on the child must be no later than the parent # . The signer of the child must be the owner of the parent @@ -834,7 +869,8 @@ class Credential(object): # must be done elsewhere # # @param trusted_certs: The certificates of trusted CA certificates - def verify(self, trusted_certs=None, schema=None, trusted_certs_required=True): + def verify(self, trusted_certs=None, schema=None, + trusted_certs_required=True): if not self.xml: self.decode() @@ -846,8 +882,9 @@ class Credential(object): xmlschema = etree.XMLSchema(schema_doc) if not xmlschema.validate(tree): error = xmlschema.error_log.last_error - message = "{}: {} (line {})".format(self.pretty_cred(), - error.message, error.line) + message = "{}: {} (line {})"\ + .format(self.pretty_cred(), + error.message, error.line) raise CredentialNotVerifiable(message) if trusted_certs_required and trusted_certs is None: @@ -856,8 +893,8 @@ class Credential(object): # trusted_cert_objects = [GID(filename=f) for f in trusted_certs] trusted_cert_objects = [] ok_trusted_certs = [] - # If caller explicitly passed in None that means skip cert chain validation. - # Strange and not typical + # If caller explicitly passed in None, that means + # skip cert chain validation. Strange and not typical if trusted_certs is not None: for f in trusted_certs: try: @@ -866,32 +903,34 @@ class Credential(object): trusted_cert_objects.append(GID(filename=f)) ok_trusted_certs.append(f) except Exception as exc: - logger.error( - "Failed to load trusted cert from {}: {}".format(f, exc)) + logger.exception( + "Failed to load trusted cert from {}".format(f)) trusted_certs = ok_trusted_certs # make sure it is not expired if self.get_expiration() < datetime.datetime.utcnow(): - raise CredentialNotVerifiable("Credential {} expired at {}" - .format(self.pretty_cred(), - self.expiration.strftime(SFATIME_FORMAT))) + raise CredentialNotVerifiable( + "Credential {} expired at {}" + .format(self.pretty_cred(), + self.expiration.strftime(SFATIME_FORMAT))) # Verify the signatures filename = self.save_to_random_tmp_file() - # If caller explicitly passed in None that means skip cert chain validation. - # - Strange and not typical + # If caller explicitly passed in None that means + # skip cert chain validation. Strange and not typical if trusted_certs is not None: # Verify the caller and object gids of this cred and of its parents for cur_cred in self.get_credential_list(): - # check both the caller and the subject - for gid in cur_cred.get_gid_object(), cur_cred.get_gid_caller(): + # check both the caller and the subject + for gid in (cur_cred.get_gid_object(), + cur_cred.get_gid_caller()): logger.debug("Credential.verify: verifying chain {}" .format(gid.pretty_cert())) logger.debug("Credential.verify: against trusted {}" .format(" ".join(trusted_certs))) gid.verify_chain(trusted_cert_objects) - + refs = [] refs.append("Sig_{}".format(self.get_refid())) @@ -900,16 +939,18 @@ class Credential(object): refs.append("Sig_{}".format(ref)) for ref in refs: - # If caller explicitly passed in None that means skip xmlsec1 validation. - # Strange and not typical + # If caller explicitly passed in None that means + # skip xmlsec1 validation. Strange and not typical if trusted_certs is None: break # Thierry - jan 2015 - # up to fedora20 we used os.popen and checked that the output begins with OK - # turns out, with fedora21, there is extra input before this 'OK' thing - # looks like we're better off just using the exit code - that's what it is made for - #cert_args = " ".join(['--trusted-pem {}'.format(x) for x in trusted_certs]) + # up to fedora20 we used os.popen and checked + # that the output begins with OK; turns out, with fedora21, + # there is extra input before this 'OK' thing + # looks like we're better off just using the exit code + # that's what it is made for + # cert_args = " ".join(['--trusted-pem {}'.format(x) for x in trusted_certs]) # command = '{} --verify --node-id "{}" {} {} 2>&1'.\ # format(self.xmlsec_path, ref, cert_args, filename) xmlsec1 = self.get_xmlsec1_path() @@ -937,9 +978,11 @@ class Credential(object): mend = verified.find('\\', mstart) msg = verified[mstart:mend] logger.warning( - "Credential.verify - failed - xmlsec1 returned {}".format(verified.strip())) - raise CredentialNotVerifiable("xmlsec1 error verifying cred {} using Signature ID {}: {}" - .format(self.pretty_cred(), ref, msg)) + "Credential.verify - failed - xmlsec1 returned {}" + .format(verified.strip())) + raise CredentialNotVerifiable( + "xmlsec1 error verifying cred {} using Signature ID {}: {}" + .format(self.pretty_cred(), ref, msg)) os.remove(filename) # Verify the parents (delegation) @@ -976,9 +1019,10 @@ class Credential(object): root_target_gid = root_cred.get_gid_object() if root_cred.get_signature() is None: # malformed - raise CredentialNotVerifiable("Could not verify credential owned by {} for object {}. " - "Cred has no signature" - .format(self.gidCaller.get_urn(), self.gidObject.get_urn())) + raise CredentialNotVerifiable( + "Could not verify credential owned by {} for object {}. " + "Cred has no signature" + .format(self.gidCaller.get_urn(), self.gidObject.get_urn())) root_cred_signer = root_cred.get_signature().get_issuer_gid() @@ -999,8 +1043,8 @@ class Credential(object): # Case 2: # Allow someone to sign credential about themeselves. Used? # If not, remove this. - #root_target_gid_str = root_target_gid.save_to_string() - #root_cred_signer_str = root_cred_signer.save_to_string() + # root_target_gid_str = root_target_gid.save_to_string() + # root_cred_signer_str = root_cred_signer.save_to_string() # if root_target_gid_str == root_cred_signer_str: # # cred signer is target, return success # return @@ -1022,15 +1066,16 @@ class Credential(object): if trusted_gids and len(trusted_gids) > 0: root_cred_signer.verify_chain(trusted_gids) else: - logger.debug("Cannot verify that cred signer is signed by a trusted authority. " - "No trusted gids. Skipping that check.") + logger.debug( + "Cannot verify that cred signer is signed by a trusted authority. " + "No trusted gids. Skipping that check.") # See if the signer is an authority over the domain of the target. # There are multiple types of authority - accept them all here # Maybe should be (hrn, type) = urn_to_hrn(root_cred_signer.get_urn()) root_cred_signer_type = root_cred_signer.get_type() if root_cred_signer_type.find('authority') == 0: - #logger.debug('Cred signer is an authority') + # logger.debug('Cred signer is an authority') # signer is an authority, see if target is in authority's domain signerhrn = root_cred_signer.get_hrn() if hrn_authfor_hrn(signerhrn, root_target_gid.get_hrn()): @@ -1115,8 +1160,8 @@ class Credential(object): def delegate(self, delegee_gidfile, caller_keyfile, caller_gidfile): """ - Return a delegated copy of this credential, delegated to the - specified gid's user. + Return a delegated copy of this credential, delegated to the + specified gid's user. """ # get the gid of the object we are delegating object_gid = self.get_gid_object() @@ -1126,8 +1171,8 @@ class Credential(object): delegee_gid = GID(filename=delegee_gidfile) delegee_hrn = delegee_gid.get_hrn() - #user_key = Keypair(filename=keyfile) - #user_hrn = self.get_gid_caller().get_hrn() + # user_key = Keypair(filename=keyfile) + # user_hrn = self.get_gid_caller().get_hrn() subject_string = "{} delegated to {}".format(object_hrn, delegee_hrn) dcred = Credential(subject=subject_string) dcred.set_gid_caller(delegee_gid) @@ -1136,7 +1181,7 @@ class Credential(object): dcred.set_expiration(self.get_expiration()) dcred.set_privileges(self.get_privileges()) dcred.get_privileges().delegate_all_privileges(True) - #dcred.set_issuer_keys(keyfile, delegee_gidfile) + # dcred.set_issuer_keys(keyfile, delegee_gidfile) dcred.set_issuer_keys(caller_keyfile, caller_gidfile) dcred.encode() dcred.sign() @@ -1170,16 +1215,17 @@ class Credential(object): # it's probably the former if caller_type == "user" and issuer_type != "user": actual_caller_hrn = caller_hrn - # if we find that the caller_hrn is an immediate descendant of the issuer, then - # this seems to be a 'regular' credential + # if we find that the caller_hrn is an immediate descendant + # of the issuer, then this seems to be a 'regular' credential elif caller_hrn.startswith(issuer_hrn): actual_caller_hrn = caller_hrn # else this looks like a delegated credential, and the real caller is # the issuer else: actual_caller_hrn = issuer_hrn - logger.info("actual_caller_hrn: caller_hrn={}, issuer_hrn={}, returning {}" - .format(caller_hrn, issuer_hrn, actual_caller_hrn)) + logger.info( + "actual_caller_hrn: caller_hrn={}, issuer_hrn={}, returning {}" + .format(caller_hrn, issuer_hrn, actual_caller_hrn)) return actual_caller_hrn ## @@ -1208,7 +1254,8 @@ class Credential(object): if self.get_signature(): result += " gidIssuer:\n" - result += self.get_signature().get_issuer_gid().dump_string(8, dump_parents) + result += self.get_signature().get_issuer_gid()\ + .dump_string(8, dump_parents) if self.expiration: result += " expiration: " + \