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     An SfaApi instance is a basic xmlrcp service
  23     augmented with the local cryptographic material and hrn
  24
  25     It also has the notion of its own interface (a string describing
  26     whether we run a registry, aggregate or slicemgr) and has
  27     the notion of neighbour sfa services as defined
  28     in /etc/sfa/{aggregates,registries}.xml
  29
  30     Finally it contains a cache instance
  31
  32     It gets augmented by the generic layer with
  33     (*) an instance of manager (actually a manager module for now)
  34         beware that this is shared among all instances of api
  35     (*) an instance of a testbed driver
  36     """
  37
  38     def __init__ (self, encoding="utf-8", methods='sfa.methods',
  39                   config = "/etc/sfa/sfa_config",
  40                   peer_cert = None, interface = None,
  41                   key_file = None, cert_file = None, cache = None):
  42
  43         XmlrpcApi.__init__ (self, encoding)
  44
  45         # we may be just be documenting the API
  46         if config is None:
  47             return
  48         # Load configuration
  49         self.config = Config(config)
  50         self.credential = None
  51         self.auth = Auth(peer_cert)
  52         self.interface = interface
  53         self.hrn = self.config.SFA_INTERFACE_HRN
  54         self.key_file = key_file
  55         self.key = Keypair(filename=self.key_file)
  56         self.cert_file = cert_file
  57         self.cert = Certificate(filename=self.cert_file)
  58         self.cache = cache
  59         if self.cache is None:
  60             self.cache = Cache()
  61
  62         # load registries
  63         from sfa.server.registry import Registries
  64         self.registries = Registries()
  65
  66         # load aggregates
  67         from sfa.server.aggregate import Aggregates
  68         self.aggregates = Aggregates()
  69
  70         # filled later on by generic/Generic
  71         self.manager=None
  72         self._dbsession=None
  73
  74     def server_proxy(self, interface, cred, timeout=30):
  75         """
  76         Returns a connection to the specified interface. Use the specified
  77         credential to determine the caller and look for the caller's key/cert
  78         in the registry hierarchy cache.
  79         """
  80         from sfa.trust.hierarchy import Hierarchy
  81         if not isinstance(cred, Credential):
  82             cred_obj = Credential(string=cred)
  83         else:
  84             cred_obj = cred
  85         caller_gid = cred_obj.get_gid_caller()
  86         hierarchy = Hierarchy()
  87         auth_info = hierarchy.get_auth_info(caller_gid.get_hrn())
  88         key_file = auth_info.get_privkey_filename()
  89         cert_file = auth_info.get_gid_filename()
  90         server = interface.server_proxy(key_file, cert_file, timeout)
  91         return server
  92
  93     def dbsession(self):
  94         if self._dbsession is None:
  95             self._dbsession=alchemy.session()
  96         return self._dbsession
  97
  98     def close_dbsession(self):
  99         if self._dbsession is None: return
 100         alchemy.close_session(self._dbsession)
 101         self._dbsession=None
 102
 103     def getCredential(self, minimumExpiration=0):
 104         """
 105         Return a valid credential for this interface.
 106         """
 107         type = 'authority'
 108         path = self.config.SFA_DATA_DIR
 109         filename = ".".join([self.interface, self.hrn, type, "cred"])
 110         cred_filename = os.path.join(path,filename)
 111         cred = None
 112         if os.path.isfile(cred_filename):
 113             cred = Credential(filename = cred_filename)
 114             # make sure cred isnt expired
 115             if not cred.get_expiration or \
 116                datetime.datetime.utcnow() + datetime.timedelta(seconds=minimumExpiration) < cred.get_expiration():
 117                 return cred.save_to_string(save_parents=True)
 118
 119         # get a new credential
 120         if self.interface in ['registry']:
 121             cred =  self._getCredentialRaw()
 122         else:
 123             cred =  self._getCredential()
 124         cred.save_to_file(cred_filename, save_parents=True)
 125
 126         return cred.save_to_string(save_parents=True)
 127
 128
 129     def getDelegatedCredential(self, creds):
 130         """
 131         Attempt to find a credential delegated to us in
 132         the specified list of creds.
 133         """
 134         from sfa.trust.hierarchy import Hierarchy
 135         if creds and not isinstance(creds, list):
 136             creds = [creds]
 137         hierarchy = Hierarchy()
 138
 139         delegated_cred = None
 140         for cred in creds:
 141             if hierarchy.auth_exists(Credential(cred=cred).get_gid_caller().get_hrn()):
 142                 delegated_cred = cred
 143                 break
 144         return delegated_cred
 145
 146     def _getCredential(self):
 147         """
 148         Get our credential from a remote registry
 149         """
 150         from sfa.server.registry import Registries
 151         registries = Registries()
 152         registry = registries.server_proxy(self.hrn, self.key_file, self.cert_file)
 153         cert_string=self.cert.save_to_string(save_parents=True)
 154         # get self credential
 155         self_cred = registry.GetSelfCredential(cert_string, self.hrn, 'authority')
 156         # get credential
 157         cred = registry.GetCredential(self_cred, self.hrn, 'authority')
 158         return Credential(string=cred)
 159
 160     def _getCredentialRaw(self):
 161         """
 162         Get our current credential directly from the local registry.
 163         """
 164
 165         hrn = self.hrn
 166         auth_hrn = self.auth.get_authority(hrn)
 167
 168         # is this a root or sub authority
 169         if not auth_hrn or hrn == self.config.SFA_INTERFACE_HRN:
 170             auth_hrn = hrn
 171         auth_info = self.auth.get_auth_info(auth_hrn)
 172         # xxx although unlikely we might want to check for a potential leak
 173         dbsession=self.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