# Credentials are signed XML files that assign a subject gid privileges to an object gid
##
-import os
+import os,sys
from types import StringTypes
import datetime
from StringIO import StringIO
from tempfile import mkstemp
from xml.dom.minidom import Document, parseString
-from lxml import etree
-from sfa.util.faults import *
+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.sfalogging import logger
from sfa.util.sfatime import utcparse
-from sfa.trust.certificate import Keypair
from sfa.trust.credential_legacy import CredentialLegacy
-from sfa.trust.rights import Right, Rights
+from sfa.trust.rights import Right, Rights, determine_rights
from sfa.trust.gid import GID
-from sfa.util.xrn import urn_to_hrn
+from sfa.util.xrn import urn_to_hrn, hrn_authfor_hrn
# 2 weeks, in seconds
-DEFAULT_CREDENTIAL_LIFETIME = 86400 * 14
+DEFAULT_CREDENTIAL_LIFETIME = 86400 * 31
# TODO:
def get_refid(self):
+ #print>>sys.stderr," \r\n \r\n credential.py Signature get_refid\ self.refid %s " %(self.refid)
if not self.refid:
self.decode()
+ #print>>sys.stderr," \r\n \r\n credential.py Signature get_refid self.refid %s " %(self.refid)
return self.refid
def get_xml(self):
self.gid = gid
def decode(self):
- doc = parseString(self.xml)
+ try:
+ doc = parseString(self.xml)
+ except ExpatError,e:
+ logger.log_exc ("Failed to parse credential, %s"%self.xml)
+ raise
sig = doc.getElementsByTagName("Signature")[0]
self.set_refid(sig.getAttribute("xml:id").strip("Sig_"))
keyinfo = sig.getElementsByTagName("X509Data")[0]
# not be changed else the signature is no longer valid. So, once
# you have loaded an existing signed credential, do not call encode() or sign() on it.
-def filter_creds_by_caller(creds, caller_hrn):
+def filter_creds_by_caller(creds, caller_hrn_list):
"""
Returns a list of creds who's gid caller matches the
specified caller hrn
"""
if not isinstance(creds, list): creds = [creds]
+ if not isinstance(caller_hrn_list, list):
+ caller_hrn_list = [caller_hrn_list]
caller_creds = []
for cred in creds:
try:
tmp_cred = Credential(string=cred)
- if tmp_cred.get_gid_caller().get_hrn() == caller_hrn:
+ if tmp_cred.get_gid_caller().get_hrn() in caller_hrn_list:
caller_creds.append(cred)
except: pass
return caller_creds
def get_subject(self):
if not self.gidObject:
self.decode()
- return self.gidObject.get_subject()
+ return self.gidObject.get_printable_subject()
+
+ # sounds like this should be __repr__ instead ??
+ def get_summary_tostring(self):
+ if not self.gidObject:
+ self.decode()
+ obj = self.gidObject.get_printable_subject()
+ caller = self.gidCaller.get_printable_subject()
+ exp = self.get_expiration()
+ # Summarize the rights too? The issuer?
+ return "[ Grant %s rights on %s until %s ]" % (caller, obj, exp)
def get_signature(self):
if not self.signature:
# Expiration: an absolute UTC time of expiration (as either an int or string or datetime)
#
def set_expiration(self, expiration):
- if isinstance(expiration, (int,float)):
+ if isinstance(expiration, (int, float)):
self.expiration = datetime.datetime.fromtimestamp(expiration)
elif isinstance (expiration, datetime.datetime):
self.expiration = expiration
else:
logger.error ("unexpected input type in Credential.set_expiration")
+
##
# get the lifetime of the credential (always in datetime format)
- #
+
def get_expiration(self):
if not self.expiration:
self.decode()
doc = Document()
signed_cred = doc.createElement("signed-credential")
-# PG adds these. It would be nice to be consistent.
-# But it's kind of odd for PL to use PG schemas that talk
-# about tickets, and the PG CM policies.
-# Note the careful addition of attributes from the parent below...
-# signed_cred.setAttribute("xmlns:xsi", "http://www.w3.org/2001/XMLSchema-instance")
-# signed_cred.setAttribute("xsinoNamespaceSchemaLocation", "http://www.protogeni.net/resources/credential/credential.xsd")
+# Declare namespaces
+# Note that credential/policy.xsd are really the PG schemas
+# in a PL namespace.
+# Note that delegation of credentials between the 2 only really works
+# cause those schemas are identical.
+# Also note these PG schemas talk about PG tickets and CM policies.
+ signed_cred.setAttribute("xmlns:xsi", "http://www.w3.org/2001/XMLSchema-instance")
+ 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")
+
+# 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")
doc.appendChild(signed_cred)
# 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 adds attributes for namespaces (which is reasonable),
+ # Specifically, PG and PLadd 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("xsinoNamespaceSchemaLocation", "http://www.protogeni.net/resources/credential/credential.xsd")
+# 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")
+
+ # HOWEVER!
+ # PL now also declares these, with different URLs, so
+ # the code notices those attributes already existed with
+ # different values, and complains.
+ # This happens regularly on delegation now that PG and
+ # PL both declare the namespace with different URLs.
+ # If the content ever differs this is a problem,
+ # but for now it works - different URLs (values in the attributes)
+ # but the same actual schema, so using the PG schema
+ # on delegated-to-PL credentials works fine.
+
+ # Note: you could also not copy attributes
+ # which already exist. It appears that both PG and PL
+ # will actually validate a slicecred with a parent
+ # signed using PG namespaces and a child signed with PL
+ # namespaces over the whole thing. But I don't know
+ # if that is a bug in xmlsec1, an accident since
+ # 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():
for attrIx in range(0, parentRoot.attributes.length):
# Below throws InUse exception if we forgot to clone the attribute first
oldAttr = signed_cred.setAttributeNode(attr.cloneNode(True))
if oldAttr and oldAttr.value != attr.value:
- 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)
- logger.error(msg)
- raise CredentialNotVerifiable("Can't encode new valid delegated credential: %s" % msg)
+ 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)
+ logger.warn(msg)
+ #raise CredentialNotVerifiable("Can't encode new valid delegated credential: %s" % msg)
p_cred = doc.importNode(sdoc.getElementsByTagName("credential")[0], True)
p = doc.createElement("parent")
def updateRefID(self):
if not self.parent:
- self.set_refid('ref0')
+ self.set_refid('ref0')
+ #print>>sys.stderr, " \r\n \r\n updateRefID next_cred ref0 "
return []
refs = []
next_cred = self.parent
+
while next_cred:
+
refs.append(next_cred.get_refid())
if next_cred.parent:
next_cred = next_cred.parent
+ #print>>sys.stderr, " \r\n \r\n updateRefID next_cred "
else:
next_cred = None
+ #print>>sys.stderr, " \r\n \r\n updateRefID next_cred NONE"
# Find a unique refid for this credential
# Is this a signed-cred or just a cred?
if len(signed_cred) > 0:
- cred = signed_cred[0].getElementsByTagName("credential")[0]
+ creds = signed_cred[0].getElementsByTagName("credential")
signatures = signed_cred[0].getElementsByTagName("signatures")
if len(signatures) > 0:
sigs = signatures[0].getElementsByTagName("Signature")
else:
- cred = doc.getElementsByTagName("credential")[0]
+ creds = doc.getElementsByTagName("credential")
+ if creds is None or len(creds) == 0:
+ # malformed cred file
+ raise CredentialNotVerifiable("Malformed XML: No credential tag found")
+
+ # Just take the first cred if there are more than one
+ cred = creds[0]
self.set_refid(cred.getAttribute("xml:id"))
self.set_expiration(utcparse(getTextNode(cred, "expires")))
# 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 = rlist.determine_rights(type, self.gidObject.get_urn())
+ rl = determine_rights(type, self.gidObject.get_urn())
for r in rl.rights:
r.delegate = deleg
rlist.add(r)
# . That the issuer of the credential is the authority in the target's urn
# . In the case of a delegated credential, this must be true of the root
# . That all of the gids presented in the credential are valid
+ # . Including verifying GID chains, and includ the issuer
# . The credential is not expired
#
# -- For Delegates (credentials with parents)
self.decode()
# validate against RelaxNG schema
- if not self.legacy:
+ if HAVELXML and not self.legacy:
if schema and os.path.exists(schema):
tree = etree.parse(StringIO(self.xml))
schema_doc = etree.parse(schema)
xmlschema = etree.XMLSchema(schema_doc)
if not xmlschema.validate(tree):
error = xmlschema.error_log.last_error
- message = "%s (line %s)" % (error.message, error.line)
- raise CredentialNotVerifiable(message)
+ message = "%s: %s (line %s)" % (self.get_summary_tostring(), error.message, error.line)
+ raise CredentialNotVerifiable(message)
if trusted_certs_required and trusted_certs is None:
trusted_certs = []
# Failures here include unreadable files
# or non PEM files
trusted_cert_objects.append(GID(filename=f))
+ #print>>sys.stderr, " \r\n \t\t\t credential.py verify trusted_certs %s" %(GID(filename=f).get_hrn())
ok_trusted_certs.append(f)
except Exception, exc:
logger.error("Failed to load trusted cert from %s: %r", f, exc)
trusted_certs = ok_trusted_certs
+ #print>>sys.stderr, " \r\n \t\t\t credential.py verify trusted_certs elemnebts %s" %(len(trusted_certs))
# Use legacy verification if this is a legacy credential
if self.legacy:
# make sure it is not expired
if self.get_expiration() < datetime.datetime.utcnow():
- raise CredentialNotVerifiable("Credential expired at %s" % self.expiration.isoformat())
+ raise CredentialNotVerifiable("Credential %s expired at %s" % (self.get_summary_tostring(), self.expiration.isoformat()))
# Verify the signatures
filename = self.save_to_random_tmp_file()
cert_args = " ".join(['--trusted-pem %s' % x for x in trusted_certs])
# If caller explicitly passed in None that means skip cert chain validation.
- # Strange and not typical
+ # - Strange and not typical
if trusted_certs is not None:
# Verify the gids of this cred and of its parents
for cur_cred in self.get_credential_list():
cur_cred.get_gid_object().verify_chain(trusted_cert_objects)
- cur_cred.get_gid_caller().verify_chain(trusted_cert_objects)
+ cur_cred.get_gid_caller().verify_chain(trusted_cert_objects)
+ #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())
refs = []
refs.append("Sig_%s" % self.get_refid())
parentRefs = self.updateRefID()
for ref in parentRefs:
refs.append("Sig_%s" % ref)
-
+ #print>>sys.stderr, " \r\n \t\t\t credential.py verify trusted_certs refs", ref
for ref in refs:
# If caller explicitly passed in None that means skip xmlsec1 validation.
# Strange and not typical
# (self.xmlsec_path, ref, cert_args, filename)
verified = os.popen('%s --verify --node-id "%s" %s %s 2>&1' \
% (self.xmlsec_path, ref, cert_args, filename)).read()
+ #print>>sys.stderr, " \r\n \t\t\t credential.py verify filename %s verified %s " %(filename,verified)
if not verified.strip().startswith("OK"):
# xmlsec errors have a msg= which is the interesting bit.
mstart = verified.find("msg=")
mstart = mstart + 4
mend = verified.find('\\', mstart)
msg = verified[mstart:mend]
- raise CredentialNotVerifiable("xmlsec1 error verifying cred using Signature ID %s: %s %s" % (ref, msg, verified.strip()))
+ raise CredentialNotVerifiable("xmlsec1 error verifying cred %s using Signature ID %s: %s %s" % (self.get_summary_tostring(), ref, msg, verified.strip()))
os.remove(filename)
-
+
+ #print>>sys.stderr, " \r\n \t\t\t credential.py HUMMM parents %s", self.parent
# Verify the parents (delegation)
if self.parent:
self.verify_parent(self.parent)
-
- # Make sure the issuer is the target's authority
- self.verify_issuer()
+ #print>>sys.stderr, " \r\n \t\t\t credential.py verify trusted_certs parents"
+ # Make sure the issuer is the target's authority, and is
+ # itself a valid GID
+ self.verify_issuer(trusted_cert_objects)
return True
##
return list
##
- # Make sure the credential's target gid was signed by (or is the same) the entity that signed
- # the original credential or an authority over that namespace.
- def verify_issuer(self):
+ # Make sure the credential's target gid (a) was signed by or (b)
+ # is the same as the entity that signed the original credential,
+ # or (c) is an authority over the target's namespace.
+ # Also ensure that the credential issuer / signer itself has a valid
+ # GID signature chain (signed by an authority with namespace rights).
+ def verify_issuer(self, trusted_gids):
root_cred = self.get_credential_list()[-1]
root_target_gid = root_cred.get_gid_object()
root_cred_signer = root_cred.get_signature().get_issuer_gid()
+ # Case 1:
+ # Allow non authority to sign target and cred about target.
+ #
+ # Why do we need to allow non authorities to sign?
+ # If in the target gid validation step we correctly
+ # checked that the target is only signed by an authority,
+ # then this is just a special case of case 3.
+ # This short-circuit is the common case currently -
+ # and cause GID validation doesn't check 'authority',
+ # this allows users to generate valid slice credentials.
if root_target_gid.is_signed_by_cert(root_cred_signer):
# cred signer matches target signer, return success
return
- 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
+ # 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()
+ #if root_target_gid_str == root_cred_signer_str:
+ # # cred signer is target, return success
+ # return
+
+ # Case 3:
+
+ # root_cred_signer is not the target_gid
+ # So this is a different gid that we have not verified.
+ # xmlsec1 verified the cert chain on this already, but
+ # it hasn't verified that the gid meets the HRN namespace
+ # requirements.
+ # Below we'll ensure that it is an authority.
+ # But we haven't verified that it is _signed by_ an authority
+ # We also don't know if xmlsec1 requires that cert signers
+ # are marked as CAs.
+
+ # Note that if verify() gave us no trusted_gids then this
+ # call will fail. So skip it if we have no trusted_gids
+ if trusted_gids and len(trusted_gids) > 0:
+ root_cred_signer.verify_chain(trusted_gids)
+ else:
+ logger.debug("No trusted gids. Cannot verify that cred signer is signed by a trusted authority. Skipping that check.")
- # See if it the signer is an authority over the domain of the target
+ # 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 == 'authority'):
- #sfa_logger.debug('Cred signer is an authority')
+ if (root_cred_signer_type.find('authority') == 0):
+ #logger.debug('Cred signer is an authority')
# signer is an authority, see if target is in authority's domain
- hrn = root_cred_signer.get_hrn()
- if root_target_gid.get_hrn().startswith(hrn):
+ signerhrn = root_cred_signer.get_hrn()
+ if hrn_authfor_hrn(signerhrn, root_target_gid.get_hrn()):
return
# We've required that the credential be signed by an authority
# . 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
def verify_parent(self, parent_cred):
+ #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())
# make sure the rights given to the child are a subset of the
# parents rights (and check delegate bits)
if not parent_cred.get_privileges().is_superset(self.get_privileges()):
- raise ChildRightsNotSubsetOfParent(("Parent cred ref %s rights " % self.parent.get_refid()) +
- self.parent.get_privileges().save_to_string() + (" not superset of delegated cred ref %s rights " % self.get_refid()) +
+ raise ChildRightsNotSubsetOfParent(("Parent cred ref %s rights " % parent_cred.get_refid()) +
+ self.parent.get_privileges().save_to_string() + (" not superset of delegated cred %s ref %s rights " % (self.get_summary_tostring(), self.get_refid())) +
self.get_privileges().save_to_string())
# make sure my target gid is the same as the parent's
if not parent_cred.get_gid_object().save_to_string() == \
self.get_gid_object().save_to_string():
- raise CredentialNotVerifiable("Target gid not equal between parent and child")
+ raise CredentialNotVerifiable("Delegated cred %s: Target gid not equal between parent and child. Parent %s" % (self.get_summary_tostring(), parent_cred.get_summary_tostring()))
# make sure my expiry time is <= my parent's
if not parent_cred.get_expiration() >= self.get_expiration():
- raise CredentialNotVerifiable("Delegated credential expires after parent")
+ raise CredentialNotVerifiable("Delegated credential %s expires after parent %s" % (self.get_summary_tostring(), parent_cred.get_summary_tostring()))
# make sure my signer is the parent's caller
if not parent_cred.get_gid_caller().save_to_string(False) == \
self.get_signature().get_issuer_gid().save_to_string(False):
- raise CredentialNotVerifiable("Delegated credential not signed by parent caller")
+ raise CredentialNotVerifiable("Delegated credential %s not signed by parent %s's caller" % (self.get_summary_tostring(), parent_cred.get_summary_tostring()))
# Recurse
if parent_cred.parent:
# only informative
def get_filename(self):
return getattr(self,'filename',None)
-
+
##
# Dump the contents of a credential to stdout in human-readable format
#
if self.parent and dump_parents:
result += "\nPARENT"
- result += self.parent.dump(True)
+ result += self.parent.dump_string(True)
return result
git://git.onelab.eu / sfa.git / blobdiff