sfa/plc/api.py

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