sfa/plc/api.py

   1 #
   2 # SFA XML-RPC and SOAP interfaces
   3 #
   4
   5 import sys
   6 import os
   7 import traceback
   8 import string
   9 import xmlrpclib
  10
  11 from sfa.util.faults import *
  12 from sfa.util.api import *
  13 from sfa.util.config import *
  14 from sfa.util.sfalogging import sfa_logger
  15 import sfa.util.xmlrpcprotocol as xmlrpcprotocol
  16 from sfa.trust.auth import Auth
  17 from sfa.trust.rights import Right, Rights, determine_rights
  18 from sfa.trust.credential import Credential,Keypair
  19 from sfa.trust.certificate import Certificate
  20 from sfa.util.namespace import get_authority, hrn_to_pl_slicename, hrn_to_pl_slicename, hrn_to_urn, slicename_to_hrn, hostname_to_hrn
  21 from sfa.util.nodemanager import NodeManager
  22 try:
  23     from collections import defaultdict
  24 except:
  25     class defaultdict(dict):
  26         def __init__(self, default_factory=None, *a, **kw):
  27             if (default_factory is not None and
  28                 not hasattr(default_factory, '__call__')):
  29                 raise TypeError('first argument must be callable')
  30             dict.__init__(self, *a, **kw)
  31             self.default_factory = default_factory
  32         def __getitem__(self, key):
  33             try:
  34                 return dict.__getitem__(self, key)
  35             except KeyError:
  36                 return self.__missing__(key)
  37         def __missing__(self, key):
  38             if self.default_factory is None:
  39                 raise KeyError(key)
  40             self[key] = value = self.default_factory()
  41             return value
  42         def __reduce__(self):
  43             if self.default_factory is None:
  44                 args = tuple()
  45             else:
  46                 args = self.default_factory,
  47             return type(self), args, None, None, self.items()
  48         def copy(self):
  49             return self.__copy__()
  50         def __copy__(self):
  51             return type(self)(self.default_factory, self)
  52         def __deepcopy__(self, memo):
  53             import copy
  54             return type(self)(self.default_factory,
  55                               copy.deepcopy(self.items()))
  56         def __repr__(self):
  57             return 'defaultdict(%s, %s)' % (self.default_factory,
  58                                             dict.__repr__(self))
  59 ## end of http://code.activestate.com/recipes/523034/ }}}
  60
  61 def list_to_dict(recs, key):
  62     """
  63     convert a list of dictionaries into a dictionary keyed on the
  64     specified dictionary key
  65     """
  66     keys = [rec[key] for rec in recs]
  67     return dict(zip(keys, recs))
  68
  69 class SfaAPI(BaseAPI):
  70
  71     # flat list of method names
  72     import sfa.methods
  73     methods = sfa.methods.all
  74
  75     def __init__(self, config = "/etc/sfa/sfa_config.py", encoding = "utf-8",
  76                  methods='sfa.methods', peer_cert = None, interface = None,
  77                 key_file = None, cert_file = None, cache = None):
  78         BaseAPI.__init__(self, config=config, encoding=encoding, methods=methods, \
  79                          peer_cert=peer_cert, interface=interface, key_file=key_file, \
  80                          cert_file=cert_file, cache=cache)
  81
  82         self.encoding = encoding
  83         from sfa.util.table import SfaTable
  84         self.SfaTable = SfaTable
  85         # Better just be documenting the API
  86         if config is None:
  87             return
  88
  89         # Load configuration
  90         self.config = Config(config)
  91         self.auth = Auth(peer_cert)
  92         self.interface = interface
  93         self.key_file = key_file
  94         self.key = Keypair(filename=self.key_file)
  95         self.cert_file = cert_file
  96         self.cert = Certificate(filename=self.cert_file)
  97         self.credential = None
  98         # Initialize the PLC shell only if SFA wraps a myPLC
  99         rspec_type = self.config.get_aggregate_type()
 100         if (rspec_type == 'pl' or rspec_type == 'vini' or rspec_type == 'eucalyptus'):
 101             self.plshell = self.getPLCShell()
 102             self.plshell_version = "4.3"
 103
 104         self.hrn = self.config.SFA_INTERFACE_HRN
 105         self.time_format = "%Y-%m-%d %H:%M:%S"
 106         self.logger=sfa_logger()
 107
 108     def getPLCShell(self):
 109         self.plauth = {'Username': self.config.SFA_PLC_USER,
 110                        'AuthMethod': 'password',
 111                        'AuthString': self.config.SFA_PLC_PASSWORD}
 112         try:
 113             sys.path.append(os.path.dirname(os.path.realpath("/usr/bin/plcsh")))
 114             self.plshell_type = 'direct'
 115             import PLC.Shell
 116             shell = PLC.Shell.Shell(globals = globals())
 117         except:
 118             self.plshell_type = 'xmlrpc'
 119             url = self.config.SFA_PLC_URL
 120             shell = xmlrpclib.Server(url, verbose = 0, allow_none = True)
 121
 122         return shell
 123
 124     def getCredential(self):
 125         """
 126         Return a valid credential for this interface.
 127         """
 128         if self.interface in ['registry']:
 129             return self.getCredentialFromLocalRegistry()
 130         else:
 131             return self.getCredentialFromRegistry()
 132
 133     def getDelegatedCredential(self, creds):
 134         """
 135         Attempt to find a credential delegated to us in
 136         the specified list of creds.
 137         """
 138         if creds and not isinstance(creds, list):
 139             creds = [creds]
 140         delegated_creds = filter_creds_by_caller(creds,self.hrn)
 141         if not delegated_creds:
 142             return None
 143         return delegated_creds[0]
 144
 145     def getCredentialFromRegistry(self):
 146         """
 147         Get our credential from a remote registry
 148         """
 149         type = 'authority'
 150         path = self.config.SFA_DATA_DIR
 151         filename = ".".join([self.interface, self.hrn, type, "cred"])
 152         cred_filename = path + os.sep + filename
 153         try:
 154             credential = Credential(filename = cred_filename)
 155             return credential.save_to_string(save_parents=True)
 156         except IOError:
 157             from sfa.server.registry import Registries
 158             registries = Registries(self)
 159             registry = registries[self.hrn]
 160             cert_string=self.cert.save_to_string(save_parents=True)
 161             # get self credential
 162             self_cred = registry.GetSelfCredential(cert_string, self.hrn, type)
 163             # get credential
 164             cred = registry.GetCredential(self_cred, self.hrn, type)
 165
 166             # save cred to file
 167             Credential(string=cred).save_to_file(cred_filename, save_parents=True)
 168             return cred
 169
 170     def getCredentialFromLocalRegistry(self):
 171         """
 172         Get our current credential directly from the local registry.
 173         """
 174
 175         hrn = self.hrn
 176         auth_hrn = self.auth.get_authority(hrn)
 177
 178         # is this a root or sub authority
 179         if not auth_hrn or hrn == self.config.SFA_INTERFACE_HRN:
 180             auth_hrn = hrn
 181         auth_info = self.auth.get_auth_info(auth_hrn)
 182         table = self.SfaTable()
 183         records = table.findObjects(hrn)
 184         if not records:
 185             raise RecordNotFound
 186         record = records[0]
 187         type = record['type']
 188         object_gid = record.get_gid_object()
 189         new_cred = Credential(subject = object_gid.get_subject())
 190         new_cred.set_gid_caller(object_gid)
 191         new_cred.set_gid_object(object_gid)
 192         new_cred.set_issuer_keys(auth_info.get_privkey_filename(), auth_info.get_gid_filename())
 193
 194         r1 = determine_rights(type, hrn)
 195         new_cred.set_privileges(r1)
 196
 197         auth_kind = "authority,ma,sa"
 198
 199         new_cred.set_parent(self.auth.hierarchy.get_auth_cred(auth_hrn, kind=auth_kind))
 200
 201         new_cred.encode()
 202         new_cred.sign()
 203
 204         return new_cred.save_to_string(save_parents=True)
 205
 206
 207     def loadCredential (self):
 208         """
 209         Attempt to load credential from file if it exists. If it doesnt get
 210         credential from registry.
 211         """
 212
 213         # see if this file exists
 214         # XX This is really the aggregate's credential. Using this is easier than getting
 215         # the registry's credential from iteslf (ssl errors).
 216         ma_cred_filename = self.config.SFA_DATA_DIR + os.sep + self.interface + self.hrn + ".ma.cred"
 217         try:
 218             self.credential = Credential(filename = ma_cred_filename)
 219         except IOError:
 220             self.credential = self.getCredentialFromRegistry()
 221
 222     ##
 223     # Convert SFA fields to PLC fields for use when registering up updating
 224     # registry record in the PLC database
 225     #
 226     # @param type type of record (user, slice, ...)
 227     # @param hrn human readable name
 228     # @param sfa_fields dictionary of SFA fields
 229     # @param pl_fields dictionary of PLC fields (output)
 230
 231     def sfa_fields_to_pl_fields(self, type, hrn, record):
 232
 233         def convert_ints(tmpdict, int_fields):
 234             for field in int_fields:
 235                 if field in tmpdict:
 236                     tmpdict[field] = int(tmpdict[field])
 237
 238         pl_record = {}
 239         #for field in record:
 240         #    pl_record[field] = record[field]
 241
 242         if type == "slice":
 243             if not "instantiation" in pl_record:
 244                 pl_record["instantiation"] = "plc-instantiated"
 245             pl_record["name"] = hrn_to_pl_slicename(hrn)
 246             if "url" in record:
 247                pl_record["url"] = record["url"]
 248             if "description" in record:
 249                 pl_record["description"] = record["description"]
 250             if "expires" in record:
 251                 pl_record["expires"] = int(record["expires"])
 252
 253         elif type == "node":
 254             if not "hostname" in pl_record:
 255                 if not "hostname" in record:
 256                     raise MissingSfaInfo("hostname")
 257                 pl_record["hostname"] = record["hostname"]
 258             if not "model" in pl_record:
 259                 pl_record["model"] = "geni"
 260
 261         elif type == "authority":
 262             pl_record["login_base"] = hrn_to_pl_login_base(hrn)
 263
 264             if not "name" in pl_record:
 265                 pl_record["name"] = hrn
 266
 267             if not "abbreviated_name" in pl_record:
 268                 pl_record["abbreviated_name"] = hrn
 269
 270             if not "enabled" in pl_record:
 271                 pl_record["enabled"] = True
 272
 273             if not "is_public" in pl_record:
 274                 pl_record["is_public"] = True
 275
 276         return pl_record
 277
 278     def fill_record_pl_info(self, records):
 279         """
 280         Fill in the planetlab specific fields of a SFA record. This
 281         involves calling the appropriate PLC method to retrieve the
 282         database record for the object.
 283
 284         PLC data is filled into the pl_info field of the record.
 285
 286         @param record: record to fill in field (in/out param)
 287         """
 288         # get ids by type
 289         node_ids, site_ids, slice_ids = [], [], []
 290         person_ids, key_ids = [], []
 291         type_map = {'node': node_ids, 'authority': site_ids,
 292                     'slice': slice_ids, 'user': person_ids}
 293
 294         for record in records:
 295             for type in type_map:
 296                 if type == record['type']:
 297                     type_map[type].append(record['pointer'])
 298
 299         # get pl records
 300         nodes, sites, slices, persons, keys = {}, {}, {}, {}, {}
 301         if node_ids:
 302             node_list = self.plshell.GetNodes(self.plauth, node_ids)
 303             nodes = list_to_dict(node_list, 'node_id')
 304         if site_ids:
 305             site_list = self.plshell.GetSites(self.plauth, site_ids)
 306             sites = list_to_dict(site_list, 'site_id')
 307         if slice_ids:
 308             slice_list = self.plshell.GetSlices(self.plauth, slice_ids)
 309             slices = list_to_dict(slice_list, 'slice_id')
 310         if person_ids:
 311             person_list = self.plshell.GetPersons(self.plauth, person_ids)
 312             persons = list_to_dict(person_list, 'person_id')
 313             for person in persons:
 314                 key_ids.extend(persons[person]['key_ids'])
 315
 316         pl_records = {'node': nodes, 'authority': sites,
 317                       'slice': slices, 'user': persons}
 318
 319         if key_ids:
 320             key_list = self.plshell.GetKeys(self.plauth, key_ids)
 321             keys = list_to_dict(key_list, 'key_id')
 322
 323         # fill record info
 324         for record in records:
 325             # records with pointer==-1 do not have plc info.
 326             # for example, the top level authority records which are
 327             # authorities, but not PL "sites"
 328             if record['pointer'] == -1:
 329                 continue
 330
 331             for type in pl_records:
 332                 if record['type'] == type:
 333                     if record['pointer'] in pl_records[type]:
 334                         record.update(pl_records[type][record['pointer']])
 335                         break
 336             # fill in key info
 337             if record['type'] == 'user':
 338                 pubkeys = [keys[key_id]['key'] for key_id in record['key_ids'] if key_id in keys]
 339                 record['keys'] = pubkeys
 340
 341         # fill in record hrns
 342         records = self.fill_record_hrns(records)
 343
 344         return records
 345
 346     def fill_record_hrns(self, records):
 347         """
 348         convert pl ids to hrns
 349         """
 350
 351         # get ids
 352         slice_ids, person_ids, site_ids, node_ids = [], [], [], []
 353         for record in records:
 354             if 'site_id' in record:
 355                 site_ids.append(record['site_id'])
 356             if 'site_ids' in records:
 357                 site_ids.extend(record['site_ids'])
 358             if 'person_ids' in record:
 359                 person_ids.extend(record['person_ids'])
 360             if 'slice_ids' in record:
 361                 slice_ids.extend(record['slice_ids'])
 362             if 'node_ids' in record:
 363                 node_ids.extend(record['node_ids'])
 364
 365         # get pl records
 366         slices, persons, sites, nodes = {}, {}, {}, {}
 367         if site_ids:
 368             site_list = self.plshell.GetSites(self.plauth, site_ids, ['site_id', 'login_base'])
 369             sites = list_to_dict(site_list, 'site_id')
 370         if person_ids:
 371             person_list = self.plshell.GetPersons(self.plauth, person_ids, ['person_id', 'email'])
 372             persons = list_to_dict(person_list, 'person_id')
 373         if slice_ids:
 374             slice_list = self.plshell.GetSlices(self.plauth, slice_ids, ['slice_id', 'name'])
 375             slices = list_to_dict(slice_list, 'slice_id')
 376         if node_ids:
 377             node_list = self.plshell.GetNodes(self.plauth, node_ids, ['node_id', 'hostname'])
 378             nodes = list_to_dict(node_list, 'node_id')
 379
 380         # convert ids to hrns
 381         for record in records:
 382
 383             # get all relevant data
 384             type = record['type']
 385             pointer = record['pointer']
 386             auth_hrn = self.hrn
 387             login_base = ''
 388             if pointer == -1:
 389                 continue
 390
 391             if 'site_id' in record:
 392                 site = sites[record['site_id']]
 393                 login_base = site['login_base']
 394                 record['site'] = ".".join([auth_hrn, login_base])
 395             if 'person_ids' in record:
 396                 emails = [persons[person_id]['email'] for person_id in record['person_ids'] \
 397                           if person_id in  persons]
 398                 usernames = [email.split('@')[0] for email in emails]
 399                 person_hrns = [".".join([auth_hrn, login_base, username]) for username in usernames]
 400                 record['persons'] = person_hrns
 401             if 'slice_ids' in record:
 402                 slicenames = [slices[slice_id]['name'] for slice_id in record['slice_ids'] \
 403                               if slice_id in slices]
 404                 slice_hrns = [slicename_to_hrn(auth_hrn, slicename) for slicename in slicenames]
 405                 record['slices'] = slice_hrns
 406             if 'node_ids' in record:
 407                 hostnames = [nodes[node_id]['hostname'] for node_id in record['node_ids'] \
 408                              if node_id in nodes]
 409                 node_hrns = [hostname_to_hrn(auth_hrn, login_base, hostname) for hostname in hostnames]
 410                 record['nodes'] = node_hrns
 411             if 'site_ids' in record:
 412                 login_bases = [sites[site_id]['login_base'] for site_id in record['site_ids'] \
 413                                if site_id in sites]
 414                 site_hrns = [".".join([auth_hrn, lbase]) for lbase in login_bases]
 415                 record['sites'] = site_hrns
 416
 417         return records
 418
 419     def fill_record_sfa_info(self, records):
 420
 421         def startswith(prefix, values):
 422             return [value for value in values if value.startswith(prefix)]
 423
 424         # get person ids
 425         person_ids = []
 426         site_ids = []
 427         for record in records:
 428             person_ids.extend(record.get("person_ids", []))
 429             site_ids.extend(record.get("site_ids", []))
 430             if 'site_id' in record:
 431                 site_ids.append(record['site_id'])
 432
 433         # get all pis from the sites we've encountered
 434         # and store them in a dictionary keyed on site_id
 435         site_pis = {}
 436         if site_ids:
 437             pi_filter = {'|roles': ['pi'], '|site_ids': site_ids}
 438             pi_list = self.plshell.GetPersons(self.plauth, pi_filter, ['person_id', 'site_ids'])
 439             for pi in pi_list:
 440                 # we will need the pi's hrns also
 441                 person_ids.append(pi['person_id'])
 442
 443                 # we also need to keep track of the sites these pis
 444                 # belong to
 445                 for site_id in pi['site_ids']:
 446                     if site_id in site_pis:
 447                         site_pis[site_id].append(pi)
 448                     else:
 449                         site_pis[site_id] = [pi]
 450
 451         # get sfa records for all records associated with these records.
 452         # we'll replace pl ids (person_ids) with hrns from the sfa records
 453         # we obtain
 454
 455         # get the sfa records
 456         table = self.SfaTable()
 457         person_list, persons = [], {}
 458         person_list = table.find({'type': 'user', 'pointer': person_ids})
 459         # create a hrns keyed on the sfa record's pointer.
 460         # Its possible for  multiple records to have the same pointer so
 461         # the dict's value will be a list of hrns.
 462         persons = defaultdict(list)
 463         for person in person_list:
 464             persons[person['pointer']].append(person)
 465
 466         # get the pl records
 467         pl_person_list, pl_persons = [], {}
 468         pl_person_list = self.plshell.GetPersons(self.plauth, person_ids, ['person_id', 'roles'])
 469         pl_persons = list_to_dict(pl_person_list, 'person_id')
 470
 471         # fill sfa info
 472         for record in records:
 473             # skip records with no pl info (top level authorities)
 474             if record['pointer'] == -1:
 475                 continue
 476             sfa_info = {}
 477             type = record['type']
 478             if (type == "slice"):
 479                 # all slice users are researchers
 480                 record['PI'] = []
 481                 record['researcher'] = []
 482                 for person_id in record['person_ids']:
 483                     hrns = [person['hrn'] for person in persons[person_id]]
 484                     record['researcher'].extend(hrns)
 485
 486                 # pis at the slice's site
 487                 pl_pis = site_pis[record['site_id']]
 488                 pi_ids = [pi['person_id'] for pi in pl_pis]
 489                 for person_id in pi_ids:
 490                     hrns = [person['hrn'] for person in persons[person_id]]
 491                     record['PI'].extend(hrns)
 492                 record['geni_urn'] = hrn_to_urn(record['hrn'], 'slice')
 493                 record['geni_creator'] = record['PI']
 494
 495             elif (type == "authority"):
 496                 record['PI'] = []
 497                 record['operator'] = []
 498                 record['owner'] = []
 499                 for pointer in record['person_ids']:
 500                     if pointer not in persons or pointer not in pl_persons:
 501                         # this means there is not sfa or pl record for this user
 502                         continue
 503                     hrns = [person['hrn'] for person in persons[pointer]]
 504                     roles = pl_persons[pointer]['roles']
 505                     if 'pi' in roles:
 506                         record['PI'].extend(hrns)
 507                     if 'tech' in roles:
 508                         record['operator'].extend(hrns)
 509                     if 'admin' in roles:
 510                         record['owner'].extend(hrns)
 511                     # xxx TODO: OrganizationName
 512             elif (type == "node"):
 513                 sfa_info['dns'] = record.get("hostname", "")
 514                 # xxx TODO: URI, LatLong, IP, DNS
 515
 516             elif (type == "user"):
 517                 sfa_info['email'] = record.get("email", "")
 518                 sfa_info['geni_urn'] = hrn_to_urn(record['hrn'], 'user')
 519                 sfa_info['geni_certificate'] = record['gid']
 520                 # xxx TODO: PostalAddress, Phone
 521             record.update(sfa_info)
 522
 523     def fill_record_info(self, records):
 524         """
 525         Given a SFA record, fill in the PLC specific and SFA specific
 526         fields in the record.
 527         """
 528         if not isinstance(records, list):
 529             records = [records]
 530
 531         self.fill_record_pl_info(records)
 532         self.fill_record_sfa_info(records)
 533
 534     def update_membership_list(self, oldRecord, record, listName, addFunc, delFunc):
 535         # get a list of the HRNs tht are members of the old and new records
 536         if oldRecord:
 537             oldList = oldRecord.get(listName, [])
 538         else:
 539             oldList = []
 540         newList = record.get(listName, [])
 541
 542         # if the lists are the same, then we don't have to update anything
 543         if (oldList == newList):
 544             return
 545
 546         # build a list of the new person ids, by looking up each person to get
 547         # their pointer
 548         newIdList = []
 549         table = self.SfaTable()
 550         records = table.find({'type': 'user', 'hrn': newList})
 551         for rec in records:
 552             newIdList.append(rec['pointer'])
 553
 554         # build a list of the old person ids from the person_ids field
 555         if oldRecord:
 556             oldIdList = oldRecord.get("person_ids", [])
 557             containerId = oldRecord.get_pointer()
 558         else:
 559             # if oldRecord==None, then we are doing a Register, instead of an
 560             # update.
 561             oldIdList = []
 562             containerId = record.get_pointer()
 563
 564     # add people who are in the new list, but not the oldList
 565         for personId in newIdList:
 566             if not (personId in oldIdList):
 567                 addFunc(self.plauth, personId, containerId)
 568
 569         # remove people who are in the old list, but not the new list
 570         for personId in oldIdList:
 571             if not (personId in newIdList):
 572                 delFunc(self.plauth, personId, containerId)
 573
 574     def update_membership(self, oldRecord, record):
 575         if record.type == "slice":
 576             self.update_membership_list(oldRecord, record, 'researcher',
 577                                         self.plshell.AddPersonToSlice,
 578                                         self.plshell.DeletePersonFromSlice)
 579         elif record.type == "authority":
 580             # xxx TODO
 581             pass
 582
 583
 584
 585 class ComponentAPI(BaseAPI):
 586
 587     def __init__(self, config = "/etc/sfa/sfa_config.py", encoding = "utf-8", methods='sfa.methods',
 588                  peer_cert = None, interface = None, key_file = None, cert_file = None):
 589
 590         BaseAPI.__init__(self, config=config, encoding=encoding, methods=methods, peer_cert=peer_cert,
 591                          interface=interface, key_file=key_file, cert_file=cert_file)
 592         self.encoding = encoding
 593
 594         # Better just be documenting the API
 595         if config is None:
 596             return
 597
 598         self.nodemanager = NodeManager(self.config)
 599
 600     def sliver_exists(self):
 601         sliver_dict = self.nodemanager.GetXIDs()
 602         if slicename in sliver_dict.keys():
 603             return True
 604         else:
 605             return False
 606
 607     def get_registry(self):
 608         addr, port = self.config.SFA_REGISTRY_HOST, self.config.SFA_REGISTRY_PORT
 609         url = "http://%(addr)s:%(port)s" % locals()
 610         server = xmlrpcprotocol.get_server(url, self.key_file, self.cert_file)
 611         return server
 612
 613     def get_node_key(self):
 614         # this call requires no authentication,
 615         # so we can generate a random keypair here
 616         subject="component"
 617         (kfd, keyfile) = tempfile.mkstemp()
 618         (cfd, certfile) = tempfile.mkstemp()
 619         key = Keypair(create=True)
 620         key.save_to_file(keyfile)
 621         cert = Certificate(subject=subject)
 622         cert.set_issuer(key=key, subject=subject)
 623         cert.set_pubkey(key)
 624         cert.sign()
 625         cert.save_to_file(certfile)
 626         registry = self.get_registry()
 627         # the registry will scp the key onto the node
 628         registry.get_key()
 629
 630     def getCredential(self):
 631         """
 632         Get our credential from a remote registry
 633         """
 634         path = self.config.SFA_DATA_DIR
 635         config_dir = self.config.config_path
 636         cred_filename = path + os.sep + 'node.cred'
 637         try:
 638             credential = Credential(filename = cred_filename)
 639             return credential.save_to_string(save_parents=True)
 640         except IOError:
 641             node_pkey_file = config_dir + os.sep + "node.key"
 642             node_gid_file = config_dir + os.sep + "node.gid"
 643             cert_filename = path + os.sep + 'server.cert'
 644             if not os.path.exists(node_pkey_file) or \
 645                not os.path.exists(node_gid_file):
 646                 self.get_node_key()
 647
 648             # get node's hrn
 649             gid = GID(filename=node_gid_file)
 650             hrn = gid.get_hrn()
 651             # get credential from registry
 652             cert_str = Certificate(filename=cert_filename).save_to_string(save_parents=True)
 653             registry = self.get_registry()
 654             cred = registry.GetSelfCredential(cert_str, hrn, 'node')
 655             Credential(string=cred).save_to_file(credfile, save_parents=True)
 656
 657             return cred
 658
 659     def clean_key_cred(self):
 660         """
 661         remove the existing keypair and cred  and generate new ones
 662         """
 663         files = ["server.key", "server.cert", "node.cred"]
 664         for f in files:
 665             filepath = KEYDIR + os.sep + f
 666             if os.path.isfile(filepath):
 667                 os.unlink(f)
 668
 669         # install the new key pair
 670         # GetCredential will take care of generating the new keypair
 671         # and credential
 672         self.get_node_key()
 673         self.getCredential()
 674
 675