sfa/server/sfaapi.py

   1 import os
   2 import os.path
   3 import datetime
   4
   5 from sfa.util.faults import SfaFault, SfaAPIError, RecordNotFound
   6 from sfa.util.genicode import GENICODE
   7 from sfa.util.config import Config
   8 from sfa.util.cache import Cache
   9
  10 from sfa.trust.auth import Auth
  11 from sfa.trust.certificate import Keypair, Certificate
  12 from sfa.trust.credential import Credential
  13 from sfa.trust.rights import determine_rights
  14 from sfa.util.version import version_core
  15 from sfa.server.xmlrpcapi import XmlrpcApi
  16 from sfa.client.return_value import ReturnValue
  17
  18 from sfa.storage.alchemy import alchemy
  19
  20 ####################
  21
  22
  23 class SfaApi (XmlrpcApi):
  24     """
  25     An SfaApi instance is a basic xmlrpc service
  26     augmented with the local cryptographic material and hrn
  27
  28     It also has the notion of its own interface (a string describing
  29     whether we run a registry, aggregate or slicemgr) and has
  30     the notion of neighbour sfa services as defined
  31     in /etc/sfa/{aggregates,registries}.xml
  32
  33     Finally it contains a cache instance
  34
  35     It gets augmented by the generic layer with
  36     (*) an instance of manager (actually a manager module for now)
  37         beware that this is shared among all instances of api
  38     (*) an instance of a testbed driver
  39     """
  40
  41     def __init__(self, encoding="utf-8", methods='sfa.methods',
  42                  config="/etc/sfa/sfa_config",
  43                  peer_cert=None, interface=None,
  44                  key_file=None, cert_file=None, cache=None):
  45
  46         XmlrpcApi.__init__(self, encoding)
  47
  48         # we may be just be documenting the API
  49         if config is None:
  50             return
  51         # Load configuration
  52         self.config = Config(config)
  53         self.credential = None
  54         self.auth = Auth(peer_cert)
  55         self.interface = interface
  56         self.hrn = self.config.SFA_INTERFACE_HRN
  57         self.key_file = key_file
  58         self.key = Keypair(filename=self.key_file)
  59         self.cert_file = cert_file
  60         self.cert = Certificate(filename=self.cert_file)
  61         self.cache = cache
  62         if self.cache is None:
  63             self.cache = Cache()
  64
  65         # load registries
  66         from sfa.server.registry import Registries
  67         self.registries = Registries()
  68
  69         # load aggregates
  70         from sfa.server.aggregate import Aggregates
  71         self.aggregates = Aggregates()
  72
  73         # filled later on by generic/Generic
  74         self.manager = None
  75         self._dbsession = None
  76
  77     def server_proxy(self, interface, cred, timeout=30):
  78         """
  79         Returns a connection to the specified interface. Use the specified
  80         credential to determine the caller and look for the caller's key/cert
  81         in the registry hierarchy cache.
  82         """
  83         from sfa.trust.hierarchy import Hierarchy
  84         if not isinstance(cred, Credential):
  85             cred_obj = Credential(string=cred)
  86         else:
  87             cred_obj = cred
  88         caller_gid = cred_obj.get_gid_caller()
  89         hierarchy = Hierarchy()
  90         auth_info = hierarchy.get_auth_info(caller_gid.get_hrn())
  91         key_file = auth_info.get_privkey_filename()
  92         cert_file = auth_info.get_gid_filename()
  93         server = interface.server_proxy(key_file, cert_file, timeout)
  94         return server
  95
  96     def dbsession(self):
  97         if self._dbsession is None:
  98             self._dbsession = alchemy.session()
  99         return self._dbsession
 100
 101     def close_dbsession(self):
 102         if self._dbsession is None:
 103             return
 104         alchemy.close_session(self._dbsession)
 105         self._dbsession = None
 106
 107     def getCredential(self, minimumExpiration=0):
 108         """
 109         Return a valid credential for this interface.
 110         """
 111         type = 'authority'
 112         path = self.config.SFA_DATA_DIR
 113         filename = ".".join([self.interface, self.hrn, type, "cred"])
 114         cred_filename = os.path.join(path, filename)
 115         cred = None
 116         if os.path.isfile(cred_filename):
 117             cred = Credential(filename=cred_filename)
 118             # make sure cred isnt expired
 119             if not cred.get_expiration or \
 120                datetime.datetime.utcnow() + datetime.timedelta(seconds=minimumExpiration) < cred.get_expiration():
 121                 return cred.save_to_string(save_parents=True)
 122
 123         # get a new credential
 124         if self.interface in ['registry']:
 125             cred = self._getCredentialRaw()
 126         else:
 127             cred = self._getCredential()
 128         cred.save_to_file(cred_filename, save_parents=True)
 129
 130         return cred.save_to_string(save_parents=True)
 131
 132     def getDelegatedCredential(self, creds):
 133         """
 134         Attempt to find a credential delegated to us in
 135         the specified list of creds.
 136         """
 137         from sfa.trust.hierarchy import Hierarchy
 138         if creds and not isinstance(creds, list):
 139             creds = [creds]
 140         hierarchy = Hierarchy()
 141
 142         delegated_cred = None
 143         for cred in creds:
 144             if hierarchy.auth_exists(Credential(cred=cred).get_gid_caller().get_hrn()):
 145                 delegated_cred = cred
 146                 break
 147         return delegated_cred
 148
 149     def _getCredential(self):
 150         """
 151         Get our credential from a remote registry
 152         """
 153         from sfa.server.registry import Registries
 154         registries = Registries()
 155         registry = registries.server_proxy(
 156             self.hrn, self.key_file, self.cert_file)
 157         cert_string = self.cert.save_to_string(save_parents=True)
 158         # get self credential
 159         self_cred = registry.GetSelfCredential(
 160             cert_string, self.hrn, 'authority')
 161         # get credential
 162         cred = registry.GetCredential(self_cred, self.hrn, 'authority')
 163         return Credential(string=cred)
 164
 165     def _getCredentialRaw(self):
 166         """
 167         Get our current credential directly from the local registry.
 168         """
 169
 170         hrn = self.hrn
 171         auth_hrn = self.auth.get_authority(hrn)
 172
 173         # is this a root or sub authority
 174         if not auth_hrn or hrn == self.config.SFA_INTERFACE_HRN:
 175             auth_hrn = hrn
 176         auth_info = self.auth.get_auth_info(auth_hrn)
 177         # xxx although unlikely we might want to check for a potential leak
 178         dbsession = self.dbsession()
 179         from sfa.storage.model import RegRecord
 180         record = dbsession.query(RegRecord).filter_by(
 181             type='authority+sa', hrn=hrn).first()
 182         if not record:
 183             raise RecordNotFound(hrn)
 184         type = record.type
 185         object_gid = record.get_gid_object()
 186         new_cred = Credential(subject=object_gid.get_subject())
 187         new_cred.set_gid_caller(object_gid)
 188         new_cred.set_gid_object(object_gid)
 189         new_cred.set_issuer_keys(
 190             auth_info.get_privkey_filename(), auth_info.get_gid_filename())
 191
 192         r1 = determine_rights(type, hrn)
 193         new_cred.set_privileges(r1)
 194         new_cred.encode()
 195         new_cred.sign()
 196
 197         return new_cred
 198
 199     def loadCredential(self):
 200         """
 201         Attempt to load credential from file if it exists. If it doesnt get
 202         credential from registry.
 203         """
 204
 205         # see if this file exists
 206         # XX This is really the aggregate's credential. Using this is easier than getting
 207         # the registry's credential from iteslf (ssl errors).
 208         filename = self.interface + self.hrn + ".ma.cred"
 209         ma_cred_path = os.path.join(self.config.SFA_DATA_DIR, filename)
 210         try:
 211             self.credential = Credential(filename=ma_cred_path)
 212         except IOError:
 213             self.credential = self.getCredentialFromRegistry()
 214
 215     def get_cached_server_version(self, server):
 216         cache_key = server.url + "-version"
 217         server_version = None
 218         if self.cache:
 219             server_version = self.cache.get(cache_key)
 220         if not server_version:
 221             result = server.GetVersion()
 222             server_version = ReturnValue.get_value(result)
 223             # cache version for 24 hours
 224             self.cache.add(cache_key, server_version, ttl=60 * 60 * 24)
 225         return server_version
 226
 227     def get_geni_code(self, result):
 228         code = {
 229             'geni_code': GENICODE.SUCCESS,
 230             'am_type': 'sfa',
 231             'am_code': None,
 232         }
 233         if isinstance(result, SfaFault):
 234             code['geni_code'] = result.faultCode
 235             code['am_code'] = result.faultCode
 236
 237         return code
 238
 239     def get_geni_value(self, result):
 240         value = result
 241         if isinstance(result, SfaFault):
 242             value = ""
 243         return value
 244
 245     def get_geni_output(self, result):
 246         output = ""
 247         if isinstance(result, SfaFault):
 248             output = result.faultString
 249         return output
 250
 251     def prepare_response_am(self, result):
 252         version = version_core()
 253         response = {
 254             'geni_api': 3,
 255             'code': self.get_geni_code(result),
 256             'value': self.get_geni_value(result),
 257             'output': self.get_geni_output(result),
 258         }
 259         return response
 260
 261     def prepare_response(self, result, method=""):
 262         """
 263         Converts the specified result into a standard GENI compliant
 264         response
 265         """
 266         # as of dec 13 2011 we only support API v2
 267         if self.interface.lower() in ['aggregate', 'slicemgr']:
 268             result = self.prepare_response_am(result)
 269         return XmlrpcApi.prepare_response(self, result, method)