1 #----------------------------------------------------------------------
2 # Copyright (c) 2008 Board of Trustees, Princeton University
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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
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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 GID. GIDs are based on certificates, and the GID class is a
25 # descendant of the certificate class.
31 from sfa.trust.certificate import Certificate
33 from sfa.util.faults import GidInvalidParentHrn, GidParentHrn
34 from sfa.util.sfalogging import logger
35 from sfa.util.xrn import hrn_to_urn, urn_to_hrn, hrn_authfor_hrn
38 # Create a new uuid. Returns the UUID as a string.
41 return str(uuid.uuid4().int)
45 # (uuid, urn, public_key)
47 # UUID is a unique identifier and is created by the python uuid module
48 # (or the utility function create_uuid() in gid.py).
50 # HRN is a human readable name. It is a dotted form similar to a backward domain
51 # name. For example, planetlab.us.arizona.bakers.
53 # URN is a human readable identifier of form:
54 # "urn:publicid:IDN+toplevelauthority[:sub-auth.]*[\res. type]\ +object name"
55 # For example, urn:publicid:IDN+planetlab:us:arizona+user+bakers
57 # PUBLIC_KEY is the public key of the principal identified by the UUID/HRN.
58 # It is a Keypair object as defined in the cert.py module.
60 # It is expected that there is a one-to-one pairing between UUIDs and HRN,
61 # but it is uncertain how this would be inforced or if it needs to be enforced.
63 # These fields are encoded using xmlrpc into the subjectAltName field of the
64 # x509 certificate. Note: Call encode() once the fields have been filled in
65 # to perform this encoding.
68 class GID(Certificate):
74 # Create a new GID object
76 # @param create If true, create the X509 certificate
77 # @param subject If subject!=None, create the X509 cert and set the subject name
78 # @param string If string!=None, load the GID from a string
79 # @param filename If filename!=None, load the GID from a file
80 # @param lifeDays life of GID in days - default is 1825==5 years
82 def __init__(self, create=False, subject=None, string=None, filename=None, uuid=None, hrn=None, urn=None, lifeDays=1825):
84 Certificate.__init__(self, lifeDays, create, subject, string, filename)
86 logger.debug("Creating GID for subject: %s" % subject)
91 self.urn = hrn_to_urn(hrn, 'unknown')
94 self.hrn, type = urn_to_hrn(urn)
96 def set_uuid(self, uuid):
97 if isinstance(uuid, str):
107 def set_hrn(self, hrn):
115 def set_urn(self, urn):
117 self.hrn, type = urn_to_hrn(urn)
127 _, t = urn_to_hrn(self.urn)
131 # Encode the GID fields and package them into the subject-alt-name field
132 # of the X509 certificate. This must be called prior to signing the
133 # certificate. It may only be called once per certificate.
139 urn = hrn_to_urn(self.hrn, None)
144 str += ", " + "URI:" + uuid.UUID(int=self.uuid).urn
146 self.set_data(str, 'subjectAltName')
152 # Decode the subject-alt-name field of the X509 certificate into the
153 # fields of the GID. This is automatically called by the various get_*()
154 # functions in this class.
157 data = self.get_data('subjectAltName')
160 if data.lower().startswith('uri:http://<params>'):
161 dict = xmlrpclib.loads(data[11:])[0][0]
163 spl = data.split(', ')
165 if val.lower().startswith('uri:urn:uuid:'):
166 dict['uuid'] = uuid.UUID(val[4:]).int
167 elif val.lower().startswith('uri:urn:publicid:idn+'):
168 dict['urn'] = val[4:]
170 self.uuid = dict.get("uuid", None)
171 self.urn = dict.get("urn", None)
172 self.hrn = dict.get("hrn", None)
174 self.hrn = urn_to_hrn(self.urn)[0]
177 # Dump the credential to stdout.
179 # @param indent specifies a number of spaces to indent the output
180 # @param dump_parents If true, also dump the parents of the GID
182 def dump(self, *args, **kwargs):
183 print self.dump_string(*args,**kwargs)
185 def dump_string(self, indent=0, dump_parents=False):
186 result=" "*(indent-2) + "GID\n"
187 result += " "*indent + "hrn:" + str(self.get_hrn()) +"\n"
188 result += " "*indent + "urn:" + str(self.get_urn()) +"\n"
189 result += " "*indent + "uuid:" + str(self.get_uuid()) + "\n"
190 filename=self.get_filename()
191 if filename: result += "Filename %s\n"%filename
193 if self.parent and dump_parents:
194 result += " "*indent + "parent:\n"
195 result += self.parent.dump_string(indent+4, dump_parents)
199 # Verify the chain of authenticity of the GID. First perform the checks
200 # of the certificate class (verifying that each parent signs the child,
201 # etc). In addition, GIDs also confirm that the parent's HRN is a prefix
202 # of the child's HRN, and the parent is of type 'authority'.
204 # Verifying these prefixes prevents a rogue authority from signing a GID
205 # for a principal that is not a member of that authority. For example,
206 # planetlab.us.arizona cannot sign a GID for planetlab.us.princeton.foo.
208 def verify_chain(self, trusted_certs = None):
209 # do the normal certificate verification stuff
210 trusted_root = Certificate.verify_chain(self, trusted_certs)
213 # make sure the parent's hrn is a prefix of the child's hrn
214 if not hrn_authfor_hrn(self.parent.get_hrn(), self.get_hrn()):
215 raise GidParentHrn("This cert HRN %s isn't in the namespace for parent HRN %s" % (self.get_hrn(), self.parent.get_hrn()))
217 # Parent must also be an authority (of some type) to sign a GID
218 # There are multiple types of authority - accept them all here
219 if not self.parent.get_type().find('authority') == 0:
220 raise GidInvalidParentHrn("This cert %s's parent %s is not an authority (is a %s)" % (self.get_hrn(), self.parent.get_hrn(), self.parent.get_type()))
222 # Then recurse up the chain - ensure the parent is a trusted
223 # root or is in the namespace of a trusted root
224 self.parent.verify_chain(trusted_certs)
226 # make sure that the trusted root's hrn is a prefix of the child's
227 trusted_gid = GID(string=trusted_root.save_to_string())
228 trusted_type = trusted_gid.get_type()
229 trusted_hrn = trusted_gid.get_hrn()
230 #if trusted_type == 'authority':
231 # trusted_hrn = trusted_hrn[:trusted_hrn.rindex('.')]
232 cur_hrn = self.get_hrn()
233 if not hrn_authfor_hrn(trusted_hrn, cur_hrn):
234 raise GidParentHrn("Trusted root with HRN %s isn't a namespace authority for this cert %s" % (trusted_hrn, cur_hrn))
236 # There are multiple types of authority - accept them all here
237 if not trusted_type.find('authority') == 0:
238 raise GidInvalidParentHrn("This cert %s's trusted root signer %s is not an authority (is a %s)" % (self.get_hrn(), trusted_hrn, trusted_type))