sfa/server/sfaapi.py

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