1 #----------------------------------------------------------------------
2 # Copyright (c) 2008 Board of Trustees, Princeton University
4 # Permission is hereby granted, free of charge, to any person obtaining
5 # a copy of this software and/or hardware specification (the "Work") to
6 # deal in the Work without restriction, including without limitation the
7 # rights to use, copy, modify, merge, publish, distribute, sublicense,
8 # and/or sell copies of the Work, and to permit persons to whom the Work
9 # is furnished to do so, subject to the following conditions:
11 # The above copyright notice and this permission notice shall be
12 # included in all copies or substantial portions of the Work.
14 # THE WORK IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
15 # OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
16 # MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
17 # NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
18 # HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
19 # WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
20 # OUT OF OR IN CONNECTION WITH THE WORK OR THE USE OR OTHER DEALINGS
22 #----------------------------------------------------------------------
24 # Implements SFA Credentials
26 # Credentials are signed XML files that assign a subject gid privileges to an object gid
30 from types import StringTypes
32 from StringIO import StringIO
33 from tempfile import mkstemp
34 from xml.dom.minidom import Document, parseString
38 from lxml import etree
43 from xml.parsers.expat import ExpatError
45 from sfa.util.faults import CredentialNotVerifiable, ChildRightsNotSubsetOfParent
46 from sfa.util.sfalogging import logger
47 from sfa.util.sfatime import utcparse
48 from sfa.trust.credential_legacy import CredentialLegacy
49 from sfa.trust.rights import Right, Rights, determine_rights
50 from sfa.trust.gid import GID
51 from sfa.util.xrn import urn_to_hrn, hrn_authfor_hrn
54 DEFAULT_CREDENTIAL_LIFETIME = 86400 * 31
58 # . make privs match between PG and PL
59 # . Need to add support for other types of credentials, e.g. tickets
60 # . add namespaces to signed-credential element?
62 signature_template = \
64 <Signature xml:id="Sig_%s" xmlns="http://www.w3.org/2000/09/xmldsig#">
66 <CanonicalizationMethod Algorithm="http://www.w3.org/TR/2001/REC-xml-c14n-20010315"/>
67 <SignatureMethod Algorithm="http://www.w3.org/2000/09/xmldsig#rsa-sha1"/>
70 <Transform Algorithm="http://www.w3.org/2000/09/xmldsig#enveloped-signature" />
72 <DigestMethod Algorithm="http://www.w3.org/2000/09/xmldsig#sha1"/>
73 <DigestValue></DigestValue>
88 # PG formats the template (whitespace) slightly differently.
89 # Note that they don't include the xmlns in the template, but add it later.
90 # Otherwise the two are equivalent.
91 #signature_template_as_in_pg = \
93 #<Signature xml:id="Sig_%s" >
95 # <CanonicalizationMethod Algorithm="http://www.w3.org/TR/2001/REC-xml-c14n-20010315"/>
96 # <SignatureMethod Algorithm="http://www.w3.org/2000/09/xmldsig#rsa-sha1"/>
97 # <Reference URI="#%s">
99 # <Transform Algorithm="http://www.w3.org/2000/09/xmldsig#enveloped-signature" />
101 # <DigestMethod Algorithm="http://www.w3.org/2000/09/xmldsig#sha1"/>
102 # <DigestValue></DigestValue>
109 # <X509IssuerSerial/>
118 # Convert a string into a bool
119 # used to convert an xsd:boolean to a Python boolean
121 if str.lower() in ['true','1']:
127 # Utility function to get the text of an XML element
129 def getTextNode(element, subele):
130 sub = element.getElementsByTagName(subele)[0]
131 if len(sub.childNodes) > 0:
132 return sub.childNodes[0].nodeValue
137 # Utility function to set the text of an XML element
138 # It creates the element, adds the text to it,
139 # and then appends it to the parent.
141 def append_sub(doc, parent, element, text):
142 ele = doc.createElement(element)
143 ele.appendChild(doc.createTextNode(text))
144 parent.appendChild(ele)
147 # Signature contains information about an xmlsec1 signature
148 # for a signed-credential
151 class Signature(object):
153 def __init__(self, string=None):
155 self.issuer_gid = None
163 #print>>sys.stderr," \r\n \r\n credential.py Signature get_refid\ self.refid %s " %(self.refid)
166 #print>>sys.stderr," \r\n \r\n credential.py Signature get_refid self.refid %s " %(self.refid)
174 def set_refid(self, id):
177 def get_issuer_gid(self):
182 def set_issuer_gid(self, gid):
187 doc = parseString(self.xml)
189 logger.log_exc ("Failed to parse credential, %s"%self.xml)
191 sig = doc.getElementsByTagName("Signature")[0]
192 self.set_refid(sig.getAttribute("xml:id").strip("Sig_"))
193 keyinfo = sig.getElementsByTagName("X509Data")[0]
194 szgid = getTextNode(keyinfo, "X509Certificate")
195 szgid = "-----BEGIN CERTIFICATE-----\n%s\n-----END CERTIFICATE-----" % szgid
196 self.set_issuer_gid(GID(string=szgid))
199 self.xml = signature_template % (self.get_refid(), self.get_refid())
203 # A credential provides a caller gid with privileges to an object gid.
204 # A signed credential is signed by the object's authority.
206 # Credentials are encoded in one of two ways. The legacy style places
207 # it in the subjectAltName of an X509 certificate. The new credentials
208 # are placed in signed XML.
211 # In general, a signed credential obtained externally should
212 # not be changed else the signature is no longer valid. So, once
213 # you have loaded an existing signed credential, do not call encode() or sign() on it.
215 def filter_creds_by_caller(creds, caller_hrn_list):
217 Returns a list of creds who's gid caller matches the
220 if not isinstance(creds, list): creds = [creds]
221 if not isinstance(caller_hrn_list, list):
222 caller_hrn_list = [caller_hrn_list]
226 tmp_cred = Credential(string=cred)
227 if tmp_cred.get_gid_caller().get_hrn() in caller_hrn_list:
228 caller_creds.append(cred)
232 class Credential(object):
235 # Create a Credential object
237 # @param create If true, create a blank x509 certificate
238 # @param subject If subject!=None, create an x509 cert with the subject name
239 # @param string If string!=None, load the credential from the string
240 # @param filename If filename!=None, load the credential from the file
241 # FIXME: create and subject are ignored!
242 def __init__(self, create=False, subject=None, string=None, filename=None):
243 self.gidCaller = None
244 self.gidObject = None
245 self.expiration = None
246 self.privileges = None
247 self.issuer_privkey = None
248 self.issuer_gid = None
249 self.issuer_pubkey = None
251 self.signature = None
256 # Check if this is a legacy credential, translate it if so
257 if string or filename:
261 str = file(filename).read()
263 if str.strip().startswith("-----"):
264 self.legacy = CredentialLegacy(False,string=str)
265 self.translate_legacy(str)
270 # Find an xmlsec1 path
271 self.xmlsec_path = ''
272 paths = ['/usr/bin','/usr/local/bin','/bin','/opt/bin','/opt/local/bin']
274 if os.path.isfile(path + '/' + 'xmlsec1'):
275 self.xmlsec_path = path + '/' + 'xmlsec1'
278 def get_subject(self):
279 if not self.gidObject:
281 return self.gidObject.get_printable_subject()
283 # sounds like this should be __repr__ instead ??
284 def get_summary_tostring(self):
285 if not self.gidObject:
287 obj = self.gidObject.get_printable_subject()
288 caller = self.gidCaller.get_printable_subject()
289 exp = self.get_expiration()
290 # Summarize the rights too? The issuer?
291 return "[ Grant %s rights on %s until %s ]" % (caller, obj, exp)
293 def get_signature(self):
294 if not self.signature:
296 return self.signature
298 def set_signature(self, sig):
303 # Translate a legacy credential into a new one
305 # @param String of the legacy credential
307 def translate_legacy(self, str):
308 legacy = CredentialLegacy(False,string=str)
309 self.gidCaller = legacy.get_gid_caller()
310 self.gidObject = legacy.get_gid_object()
311 lifetime = legacy.get_lifetime()
313 self.set_expiration(datetime.datetime.utcnow() + datetime.timedelta(seconds=DEFAULT_CREDENTIAL_LIFETIME))
315 self.set_expiration(int(lifetime))
316 self.lifeTime = legacy.get_lifetime()
317 self.set_privileges(legacy.get_privileges())
318 self.get_privileges().delegate_all_privileges(legacy.get_delegate())
321 # Need the issuer's private key and name
322 # @param key Keypair object containing the private key of the issuer
323 # @param gid GID of the issuing authority
325 def set_issuer_keys(self, privkey, gid):
326 self.issuer_privkey = privkey
327 self.issuer_gid = gid
331 # Set this credential's parent
332 def set_parent(self, cred):
337 # set the GID of the caller
339 # @param gid GID object of the caller
341 def set_gid_caller(self, gid):
343 # gid origin caller is the caller's gid by default
344 self.gidOriginCaller = gid
347 # get the GID of the object
349 def get_gid_caller(self):
350 if not self.gidCaller:
352 return self.gidCaller
355 # set the GID of the object
357 # @param gid GID object of the object
359 def set_gid_object(self, gid):
363 # get the GID of the object
365 def get_gid_object(self):
366 if not self.gidObject:
368 return self.gidObject
373 # Expiration: an absolute UTC time of expiration (as either an int or string or datetime)
375 def set_expiration(self, expiration):
376 if isinstance(expiration, (int, float)):
377 self.expiration = datetime.datetime.fromtimestamp(expiration)
378 elif isinstance (expiration, datetime.datetime):
379 self.expiration = expiration
380 elif isinstance (expiration, StringTypes):
381 self.expiration = utcparse (expiration)
383 logger.error ("unexpected input type in Credential.set_expiration")
387 # get the lifetime of the credential (always in datetime format)
389 def get_expiration(self):
390 if not self.expiration:
392 # at this point self.expiration is normalized as a datetime - DON'T call utcparse again
393 return self.expiration
397 def get_lifetime(self):
398 return self.get_expiration()
403 # @param privs either a comma-separated list of privileges of a Rights object
405 def set_privileges(self, privs):
406 if isinstance(privs, str):
407 self.privileges = Rights(string = privs)
409 self.privileges = privs
413 # return the privileges as a Rights object
415 def get_privileges(self):
416 if not self.privileges:
418 return self.privileges
421 # determine whether the credential allows a particular operation to be
424 # @param op_name string specifying name of operation ("lookup", "update", etc)
426 def can_perform(self, op_name):
427 rights = self.get_privileges()
432 return rights.can_perform(op_name)
436 # Encode the attributes of the credential into an XML string
437 # This should be done immediately before signing the credential.
439 # In general, a signed credential obtained externally should
440 # not be changed else the signature is no longer valid. So, once
441 # you have loaded an existing signed credential, do not call encode() or sign() on it.
444 # Create the XML document
446 signed_cred = doc.createElement("signed-credential")
449 # Note that credential/policy.xsd are really the PG schemas
451 # Note that delegation of credentials between the 2 only really works
452 # cause those schemas are identical.
453 # Also note these PG schemas talk about PG tickets and CM policies.
454 signed_cred.setAttribute("xmlns:xsi", "http://www.w3.org/2001/XMLSchema-instance")
455 signed_cred.setAttribute("xsi:noNamespaceSchemaLocation", "http://www.planet-lab.org/resources/sfa/credential.xsd")
456 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")
458 # PG says for those last 2:
459 # signed_cred.setAttribute("xsi:noNamespaceSchemaLocation", "http://www.protogeni.net/resources/credential/credential.xsd")
460 # 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")
462 doc.appendChild(signed_cred)
464 # Fill in the <credential> bit
465 cred = doc.createElement("credential")
466 cred.setAttribute("xml:id", self.get_refid())
467 signed_cred.appendChild(cred)
468 append_sub(doc, cred, "type", "privilege")
469 append_sub(doc, cred, "serial", "8")
470 append_sub(doc, cred, "owner_gid", self.gidCaller.save_to_string())
471 append_sub(doc, cred, "owner_urn", self.gidCaller.get_urn())
472 append_sub(doc, cred, "target_gid", self.gidObject.save_to_string())
473 append_sub(doc, cred, "target_urn", self.gidObject.get_urn())
474 append_sub(doc, cred, "uuid", "")
475 if not self.expiration:
476 self.set_expiration(datetime.datetime.utcnow() + datetime.timedelta(seconds=DEFAULT_CREDENTIAL_LIFETIME))
477 self.expiration = self.expiration.replace(microsecond=0)
478 append_sub(doc, cred, "expires", self.expiration.isoformat())
479 privileges = doc.createElement("privileges")
480 cred.appendChild(privileges)
483 rights = self.get_privileges()
484 for right in rights.rights:
485 priv = doc.createElement("privilege")
486 append_sub(doc, priv, "name", right.kind)
487 append_sub(doc, priv, "can_delegate", str(right.delegate).lower())
488 privileges.appendChild(priv)
490 # Add the parent credential if it exists
492 sdoc = parseString(self.parent.get_xml())
493 # If the root node is a signed-credential (it should be), then
494 # get all its attributes and attach those to our signed_cred
496 # Specifically, PG and PLadd attributes for namespaces (which is reasonable),
497 # and we need to include those again here or else their signature
498 # no longer matches on the credential.
499 # We expect three of these, but here we copy them all:
500 # signed_cred.setAttribute("xmlns:xsi", "http://www.w3.org/2001/XMLSchema-instance")
501 # and from PG (PL is equivalent, as shown above):
502 # signed_cred.setAttribute("xsi:noNamespaceSchemaLocation", "http://www.protogeni.net/resources/credential/credential.xsd")
503 # 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")
506 # PL now also declares these, with different URLs, so
507 # the code notices those attributes already existed with
508 # different values, and complains.
509 # This happens regularly on delegation now that PG and
510 # PL both declare the namespace with different URLs.
511 # If the content ever differs this is a problem,
512 # but for now it works - different URLs (values in the attributes)
513 # but the same actual schema, so using the PG schema
514 # on delegated-to-PL credentials works fine.
516 # Note: you could also not copy attributes
517 # which already exist. It appears that both PG and PL
518 # will actually validate a slicecred with a parent
519 # signed using PG namespaces and a child signed with PL
520 # namespaces over the whole thing. But I don't know
521 # if that is a bug in xmlsec1, an accident since
522 # the contents of the schemas are the same,
523 # or something else, but it seems odd. And this works.
524 parentRoot = sdoc.documentElement
525 if parentRoot.tagName == "signed-credential" and parentRoot.hasAttributes():
526 for attrIx in range(0, parentRoot.attributes.length):
527 attr = parentRoot.attributes.item(attrIx)
528 # returns the old attribute of same name that was
530 # Below throws InUse exception if we forgot to clone the attribute first
531 oldAttr = signed_cred.setAttributeNode(attr.cloneNode(True))
532 if oldAttr and oldAttr.value != attr.value:
533 msg = "Delegating cred from owner %s to %s over %s replaced attribute %s value '%s' with '%s'" % (self.parent.gidCaller.get_urn(), self.gidCaller.get_urn(), self.gidObject.get_urn(), oldAttr.name, oldAttr.value, attr.value)
535 #raise CredentialNotVerifiable("Can't encode new valid delegated credential: %s" % msg)
537 p_cred = doc.importNode(sdoc.getElementsByTagName("credential")[0], True)
538 p = doc.createElement("parent")
539 p.appendChild(p_cred)
541 # done handling parent credential
543 # Create the <signatures> tag
544 signatures = doc.createElement("signatures")
545 signed_cred.appendChild(signatures)
547 # Add any parent signatures
549 for cur_cred in self.get_credential_list()[1:]:
550 sdoc = parseString(cur_cred.get_signature().get_xml())
551 ele = doc.importNode(sdoc.getElementsByTagName("Signature")[0], True)
552 signatures.appendChild(ele)
554 # Get the finished product
555 self.xml = doc.toxml()
558 def save_to_random_tmp_file(self):
559 fp, filename = mkstemp(suffix='cred', text=True)
560 fp = os.fdopen(fp, "w")
561 self.save_to_file(filename, save_parents=True, filep=fp)
564 def save_to_file(self, filename, save_parents=True, filep=None):
570 f = open(filename, "w")
574 def save_to_string(self, save_parents=True):
584 def set_refid(self, rid):
588 # Figure out what refids exist, and update this credential's id
589 # so that it doesn't clobber the others. Returns the refids of
592 def updateRefID(self):
594 self.set_refid('ref0')
595 #print>>sys.stderr, " \r\n \r\n updateRefID next_cred ref0 "
600 next_cred = self.parent
604 refs.append(next_cred.get_refid())
606 next_cred = next_cred.parent
607 #print>>sys.stderr, " \r\n \r\n updateRefID next_cred "
610 #print>>sys.stderr, " \r\n \r\n updateRefID next_cred NONE"
613 # Find a unique refid for this credential
614 rid = self.get_refid()
617 rid = "ref%d" % (val + 1)
622 # Return the set of parent credential ref ids
631 # Sign the XML file created by encode()
634 # In general, a signed credential obtained externally should
635 # not be changed else the signature is no longer valid. So, once
636 # you have loaded an existing signed credential, do not call encode() or sign() on it.
639 if not self.issuer_privkey or not self.issuer_gid:
641 doc = parseString(self.get_xml())
642 sigs = doc.getElementsByTagName("signatures")[0]
644 # Create the signature template to be signed
645 signature = Signature()
646 signature.set_refid(self.get_refid())
647 sdoc = parseString(signature.get_xml())
648 sig_ele = doc.importNode(sdoc.getElementsByTagName("Signature")[0], True)
649 sigs.appendChild(sig_ele)
651 self.xml = doc.toxml()
654 # Split the issuer GID into multiple certificates if it's a chain
655 chain = GID(filename=self.issuer_gid)
658 gid_files.append(chain.save_to_random_tmp_file(False))
659 if chain.get_parent():
660 chain = chain.get_parent()
665 # Call out to xmlsec1 to sign it
666 ref = 'Sig_%s' % self.get_refid()
667 filename = self.save_to_random_tmp_file()
668 signed = os.popen('%s --sign --node-id "%s" --privkey-pem %s,%s %s' \
669 % (self.xmlsec_path, ref, self.issuer_privkey, ",".join(gid_files), filename)).read()
672 for gid_file in gid_files:
677 # This is no longer a legacy credential
686 # Retrieve the attributes of the credential from the XML.
687 # This is automatically called by the various get_* methods of
688 # this class and should not need to be called explicitly.
693 doc = parseString(self.xml)
695 signed_cred = doc.getElementsByTagName("signed-credential")
697 # Is this a signed-cred or just a cred?
698 if len(signed_cred) > 0:
699 creds = signed_cred[0].getElementsByTagName("credential")
700 signatures = signed_cred[0].getElementsByTagName("signatures")
701 if len(signatures) > 0:
702 sigs = signatures[0].getElementsByTagName("Signature")
704 creds = doc.getElementsByTagName("credential")
706 if creds is None or len(creds) == 0:
707 # malformed cred file
708 raise CredentialNotVerifiable("Malformed XML: No credential tag found")
710 # Just take the first cred if there are more than one
713 self.set_refid(cred.getAttribute("xml:id"))
714 self.set_expiration(utcparse(getTextNode(cred, "expires")))
715 self.gidCaller = GID(string=getTextNode(cred, "owner_gid"))
716 self.gidObject = GID(string=getTextNode(cred, "target_gid"))
720 privs = cred.getElementsByTagName("privileges")[0]
722 for priv in privs.getElementsByTagName("privilege"):
723 kind = getTextNode(priv, "name")
724 deleg = str2bool(getTextNode(priv, "can_delegate"))
726 # Convert * into the default privileges for the credential's type
727 # Each inherits the delegatability from the * above
728 _ , type = urn_to_hrn(self.gidObject.get_urn())
729 rl = determine_rights(type, self.gidObject.get_urn())
734 rlist.add(Right(kind.strip(), deleg))
735 self.set_privileges(rlist)
739 parent = cred.getElementsByTagName("parent")
741 parent_doc = parent[0].getElementsByTagName("credential")[0]
742 parent_xml = parent_doc.toxml()
743 self.parent = Credential(string=parent_xml)
746 # Assign the signatures to the credentials
748 Sig = Signature(string=sig.toxml())
750 for cur_cred in self.get_credential_list():
751 if cur_cred.get_refid() == Sig.get_refid():
752 cur_cred.set_signature(Sig)
757 # trusted_certs: A list of trusted GID filenames (not GID objects!)
758 # Chaining is not supported within the GIDs by xmlsec1.
760 # trusted_certs_required: Should usually be true. Set False means an
761 # empty list of trusted_certs would still let this method pass.
762 # It just skips xmlsec1 verification et al. Only used by some utils
765 # . All of the signatures are valid and that the issuers trace back
766 # to trusted roots (performed by xmlsec1)
767 # . The XML matches the credential schema
768 # . That the issuer of the credential is the authority in the target's urn
769 # . In the case of a delegated credential, this must be true of the root
770 # . That all of the gids presented in the credential are valid
771 # . Including verifying GID chains, and includ the issuer
772 # . The credential is not expired
774 # -- For Delegates (credentials with parents)
775 # . The privileges must be a subset of the parent credentials
776 # . The privileges must have "can_delegate" set for each delegated privilege
777 # . The target gid must be the same between child and parents
778 # . The expiry time on the child must be no later than the parent
779 # . The signer of the child must be the owner of the parent
781 # -- Verify does *NOT*
782 # . ensure that an xmlrpc client's gid matches a credential gid, that
783 # must be done elsewhere
785 # @param trusted_certs: The certificates of trusted CA certificates
786 def verify(self, trusted_certs=None, schema=None, trusted_certs_required=True):
790 # validate against RelaxNG schema
791 if HAVELXML and not self.legacy:
792 if schema and os.path.exists(schema):
793 tree = etree.parse(StringIO(self.xml))
794 schema_doc = etree.parse(schema)
795 xmlschema = etree.XMLSchema(schema_doc)
796 if not xmlschema.validate(tree):
797 error = xmlschema.error_log.last_error
798 message = "%s: %s (line %s)" % (self.get_summary_tostring(), error.message, error.line)
799 raise CredentialNotVerifiable(message)
801 if trusted_certs_required and trusted_certs is None:
804 # trusted_cert_objects = [GID(filename=f) for f in trusted_certs]
805 trusted_cert_objects = []
806 ok_trusted_certs = []
807 # If caller explicitly passed in None that means skip cert chain validation.
808 # Strange and not typical
809 if trusted_certs is not None:
810 for f in trusted_certs:
812 # Failures here include unreadable files
814 trusted_cert_objects.append(GID(filename=f))
815 #print>>sys.stderr, " \r\n \t\t\t credential.py verify trusted_certs %s" %(GID(filename=f).get_hrn())
816 ok_trusted_certs.append(f)
817 except Exception, exc:
818 logger.error("Failed to load trusted cert from %s: %r", f, exc)
819 trusted_certs = ok_trusted_certs
820 #print>>sys.stderr, " \r\n \t\t\t credential.py verify trusted_certs elemnebts %s" %(len(trusted_certs))
822 # Use legacy verification if this is a legacy credential
824 self.legacy.verify_chain(trusted_cert_objects)
825 if self.legacy.client_gid:
826 self.legacy.client_gid.verify_chain(trusted_cert_objects)
827 if self.legacy.object_gid:
828 self.legacy.object_gid.verify_chain(trusted_cert_objects)
831 # make sure it is not expired
832 if self.get_expiration() < datetime.datetime.utcnow():
833 raise CredentialNotVerifiable("Credential %s expired at %s" % (self.get_summary_tostring(), self.expiration.isoformat()))
835 # Verify the signatures
836 filename = self.save_to_random_tmp_file()
837 if trusted_certs is not None:
838 cert_args = " ".join(['--trusted-pem %s' % x for x in trusted_certs])
840 # If caller explicitly passed in None that means skip cert chain validation.
841 # - Strange and not typical
842 if trusted_certs is not None:
843 # Verify the gids of this cred and of its parents
844 for cur_cred in self.get_credential_list():
845 cur_cred.get_gid_object().verify_chain(trusted_cert_objects)
846 cur_cred.get_gid_caller().verify_chain(trusted_cert_objects)
847 #print>>sys.stderr, " \r\n \t\t\t credential.py verify cur_cred get_gid_object hrn %s get_gid_caller %s" %(cur_cred.get_gid_object().get_hrn(),cur_cred.get_gid_caller().get_hrn())
850 refs.append("Sig_%s" % self.get_refid())
852 parentRefs = self.updateRefID()
853 for ref in parentRefs:
854 refs.append("Sig_%s" % ref)
855 #print>>sys.stderr, " \r\n \t\t\t credential.py verify trusted_certs refs", ref
857 # If caller explicitly passed in None that means skip xmlsec1 validation.
858 # Strange and not typical
859 if trusted_certs is None:
862 # print "Doing %s --verify --node-id '%s' %s %s 2>&1" % \
863 # (self.xmlsec_path, ref, cert_args, filename)
864 verified = os.popen('%s --verify --node-id "%s" %s %s 2>&1' \
865 % (self.xmlsec_path, ref, cert_args, filename)).read()
866 #print>>sys.stderr, " \r\n \t\t\t credential.py verify filename %s verified %s " %(filename,verified)
867 if not verified.strip().startswith("OK"):
868 # xmlsec errors have a msg= which is the interesting bit.
869 mstart = verified.find("msg=")
871 if mstart > -1 and len(verified) > 4:
873 mend = verified.find('\\', mstart)
874 msg = verified[mstart:mend]
875 raise CredentialNotVerifiable("xmlsec1 error verifying cred %s using Signature ID %s: %s %s" % (self.get_summary_tostring(), ref, msg, verified.strip()))
878 #print>>sys.stderr, " \r\n \t\t\t credential.py HUMMM parents %s", self.parent
879 # Verify the parents (delegation)
881 self.verify_parent(self.parent)
882 #print>>sys.stderr, " \r\n \t\t\t credential.py verify trusted_certs parents"
883 # Make sure the issuer is the target's authority, and is
885 self.verify_issuer(trusted_cert_objects)
889 # Creates a list of the credential and its parents, with the root
890 # (original delegated credential) as the last item in the list
891 def get_credential_list(self):
895 list.append(cur_cred)
897 cur_cred = cur_cred.parent
903 # Make sure the credential's target gid (a) was signed by or (b)
904 # is the same as the entity that signed the original credential,
905 # or (c) is an authority over the target's namespace.
906 # Also ensure that the credential issuer / signer itself has a valid
907 # GID signature chain (signed by an authority with namespace rights).
908 def verify_issuer(self, trusted_gids):
909 root_cred = self.get_credential_list()[-1]
910 root_target_gid = root_cred.get_gid_object()
911 root_cred_signer = root_cred.get_signature().get_issuer_gid()
914 # Allow non authority to sign target and cred about target.
916 # Why do we need to allow non authorities to sign?
917 # If in the target gid validation step we correctly
918 # checked that the target is only signed by an authority,
919 # then this is just a special case of case 3.
920 # This short-circuit is the common case currently -
921 # and cause GID validation doesn't check 'authority',
922 # this allows users to generate valid slice credentials.
923 if root_target_gid.is_signed_by_cert(root_cred_signer):
924 # cred signer matches target signer, return success
928 # Allow someone to sign credential about themeselves. Used?
929 # If not, remove this.
930 #root_target_gid_str = root_target_gid.save_to_string()
931 #root_cred_signer_str = root_cred_signer.save_to_string()
932 #if root_target_gid_str == root_cred_signer_str:
933 # # cred signer is target, return success
938 # root_cred_signer is not the target_gid
939 # So this is a different gid that we have not verified.
940 # xmlsec1 verified the cert chain on this already, but
941 # it hasn't verified that the gid meets the HRN namespace
943 # Below we'll ensure that it is an authority.
944 # But we haven't verified that it is _signed by_ an authority
945 # We also don't know if xmlsec1 requires that cert signers
948 # Note that if verify() gave us no trusted_gids then this
949 # call will fail. So skip it if we have no trusted_gids
950 if trusted_gids and len(trusted_gids) > 0:
951 root_cred_signer.verify_chain(trusted_gids)
953 logger.debug("No trusted gids. Cannot verify that cred signer is signed by a trusted authority. Skipping that check.")
955 # See if the signer is an authority over the domain of the target.
956 # There are multiple types of authority - accept them all here
957 # Maybe should be (hrn, type) = urn_to_hrn(root_cred_signer.get_urn())
958 root_cred_signer_type = root_cred_signer.get_type()
959 if (root_cred_signer_type.find('authority') == 0):
960 #logger.debug('Cred signer is an authority')
961 # signer is an authority, see if target is in authority's domain
962 signerhrn = root_cred_signer.get_hrn()
963 if hrn_authfor_hrn(signerhrn, root_target_gid.get_hrn()):
966 # We've required that the credential be signed by an authority
967 # for that domain. Reasonable and probably correct.
968 # A looser model would also allow the signer to be an authority
969 # in my control framework - eg My CA or CH. Even if it is not
970 # the CH that issued these, eg, user credentials.
972 # Give up, credential does not pass issuer verification
974 raise CredentialNotVerifiable("Could not verify credential owned by %s for object %s. Cred signer %s not the trusted authority for Cred target %s" % (self.gidCaller.get_urn(), self.gidObject.get_urn(), root_cred_signer.get_hrn(), root_target_gid.get_hrn()))
978 # -- For Delegates (credentials with parents) verify that:
979 # . The privileges must be a subset of the parent credentials
980 # . The privileges must have "can_delegate" set for each delegated privilege
981 # . The target gid must be the same between child and parents
982 # . The expiry time on the child must be no later than the parent
983 # . The signer of the child must be the owner of the parent
984 def verify_parent(self, parent_cred):
985 #print>>sys.stderr, " \r\n\r\n \t verify_parent parent_cred.get_gid_caller().save_to_string(False) %s self.get_signature().get_issuer_gid().save_to_string(False) %s" %(parent_cred.get_gid_caller().get_hrn(),self.get_signature().get_issuer_gid().get_hrn())
986 # make sure the rights given to the child are a subset of the
987 # parents rights (and check delegate bits)
988 if not parent_cred.get_privileges().is_superset(self.get_privileges()):
989 raise ChildRightsNotSubsetOfParent(("Parent cred ref %s rights " % parent_cred.get_refid()) +
990 self.parent.get_privileges().save_to_string() + (" not superset of delegated cred %s ref %s rights " % (self.get_summary_tostring(), self.get_refid())) +
991 self.get_privileges().save_to_string())
993 # make sure my target gid is the same as the parent's
994 if not parent_cred.get_gid_object().save_to_string() == \
995 self.get_gid_object().save_to_string():
996 raise CredentialNotVerifiable("Delegated cred %s: Target gid not equal between parent and child. Parent %s" % (self.get_summary_tostring(), parent_cred.get_summary_tostring()))
998 # make sure my expiry time is <= my parent's
999 if not parent_cred.get_expiration() >= self.get_expiration():
1000 raise CredentialNotVerifiable("Delegated credential %s expires after parent %s" % (self.get_summary_tostring(), parent_cred.get_summary_tostring()))
1002 # make sure my signer is the parent's caller
1003 if not parent_cred.get_gid_caller().save_to_string(False) == \
1004 self.get_signature().get_issuer_gid().save_to_string(False):
1005 raise CredentialNotVerifiable("Delegated credential %s not signed by parent %s's caller" % (self.get_summary_tostring(), parent_cred.get_summary_tostring()))
1008 if parent_cred.parent:
1009 parent_cred.verify_parent(parent_cred.parent)
1012 def delegate(self, delegee_gidfile, caller_keyfile, caller_gidfile):
1014 Return a delegated copy of this credential, delegated to the
1015 specified gid's user.
1017 # get the gid of the object we are delegating
1018 object_gid = self.get_gid_object()
1019 object_hrn = object_gid.get_hrn()
1021 # the hrn of the user who will be delegated to
1022 delegee_gid = GID(filename=delegee_gidfile)
1023 delegee_hrn = delegee_gid.get_hrn()
1025 #user_key = Keypair(filename=keyfile)
1026 #user_hrn = self.get_gid_caller().get_hrn()
1027 subject_string = "%s delegated to %s" % (object_hrn, delegee_hrn)
1028 dcred = Credential(subject=subject_string)
1029 dcred.set_gid_caller(delegee_gid)
1030 dcred.set_gid_object(object_gid)
1031 dcred.set_parent(self)
1032 dcred.set_expiration(self.get_expiration())
1033 dcred.set_privileges(self.get_privileges())
1034 dcred.get_privileges().delegate_all_privileges(True)
1035 #dcred.set_issuer_keys(keyfile, delegee_gidfile)
1036 dcred.set_issuer_keys(caller_keyfile, caller_gidfile)
1043 def get_filename(self):
1044 return getattr(self,'filename',None)
1047 # Dump the contents of a credential to stdout in human-readable format
1049 # @param dump_parents If true, also dump the parent certificates
1050 def dump (self, *args, **kwargs):
1051 print self.dump_string(*args, **kwargs)
1054 def dump_string(self, dump_parents=False):
1056 result += "CREDENTIAL %s\n" % self.get_subject()
1057 filename=self.get_filename()
1058 if filename: result += "Filename %s\n"%filename
1059 result += " privs: %s\n" % self.get_privileges().save_to_string()
1060 gidCaller = self.get_gid_caller()
1062 result += " gidCaller:\n"
1063 result += gidCaller.dump_string(8, dump_parents)
1065 if self.get_signature():
1067 self.get_signature().get_issuer_gid().dump(8, dump_parents)
1069 gidObject = self.get_gid_object()
1071 result += " gidObject:\n"
1072 result += gidObject.dump_string(8, dump_parents)
1074 if self.parent and dump_parents:
1075 result += "\nPARENT"
1076 result += self.parent.dump_string(True)