sfa/server/sfaapi.py

   1 import os.path
   2 import datetime
   3
   4 from sfa.util.faults import SfaAPIError
   5 from sfa.util.config import Config
   6 from sfa.util.cache import Cache
   7
   8 from sfa.trust.auth import Auth
   9 from sfa.trust.certificate import Keypair, Certificate
  10 from sfa.trust.credential import Credential
  11
  12 # this is wrong all right, but temporary
  13 from sfa.managers.managerwrapper import ManagerWrapper, import_manager
  14
  15 from sfa.server.xmlrpcapi import XmlrpcApi
  16
  17 ####################
  18 class SfaApi (XmlrpcApi):
  19
  20     """
  21     An SfaApi instance is a basic xmlrcp service
  22     augmented with the local cryptographic material and hrn
  23     It also has the notion of neighbour sfa services
  24     as defined in /etc/sfa/{aggregates,registries}.xml
  25     Finally it contains a cache instance
  26     It has no a priori knowledge of the underlying testbed
  27     """
  28
  29     def __init__ (self, encoding="utf-8", methods='sfa.methods',
  30                   config = "/etc/sfa/sfa_config.py",
  31                   peer_cert = None, interface = None,
  32                   key_file = None, cert_file = None, cache = None):
  33
  34         XmlrpcApi.__init__ (self, encoding)
  35
  36         # we may be just be documenting the API
  37         if config is None:
  38             return
  39         # Load configuration
  40         self.config = Config(config)
  41         self.credential = None
  42         self.auth = Auth(peer_cert)
  43         self.interface = interface
  44         self.hrn = self.config.SFA_INTERFACE_HRN
  45         self.key_file = key_file
  46         self.key = Keypair(filename=self.key_file)
  47         self.cert_file = cert_file
  48         self.cert = Certificate(filename=self.cert_file)
  49         self.cache = cache
  50         if self.cache is None:
  51             self.cache = Cache()
  52
  53         # load registries
  54         from sfa.server.registry import Registries
  55         self.registries = Registries()
  56
  57         # load aggregates
  58         from sfa.server.aggregate import Aggregates
  59         self.aggregates = Aggregates()
  60
  61
  62     def get_interface_manager(self, manager_base = 'sfa.managers'):
  63         """
  64         Returns the appropriate manager module for this interface.
  65         Modules are usually found in sfa/managers/
  66         """
  67         manager=None
  68         if self.interface in ['registry']:
  69             manager=import_manager ("registry",  self.config.SFA_REGISTRY_TYPE)
  70         elif self.interface in ['aggregate']:
  71             manager=import_manager ("aggregate", self.config.SFA_AGGREGATE_TYPE)
  72         elif self.interface in ['slicemgr', 'sm']:
  73             manager=import_manager ("slice",     self.config.SFA_SM_TYPE)
  74         elif self.interface in ['component', 'cm']:
  75             manager=import_manager ("component", self.config.SFA_CM_TYPE)
  76         if not manager:
  77             raise SfaAPIError("No manager for interface: %s" % self.interface)
  78
  79         # this isnt necessary but will help to produce better error messages
  80         # if someone tries to access an operation this manager doesn't implement
  81         manager = ManagerWrapper(manager, self.interface)
  82
  83         return manager
  84
  85     def get_server(self, interface, cred, timeout=30):
  86         """
  87         Returns a connection to the specified interface. Use the specified
  88         credential to determine the caller and look for the caller's key/cert
  89         in the registry hierarchy cache.
  90         """
  91         from sfa.trust.hierarchy import Hierarchy
  92         if not isinstance(cred, Credential):
  93             cred_obj = Credential(string=cred)
  94         else:
  95             cred_obj = cred
  96         caller_gid = cred_obj.get_gid_caller()
  97         hierarchy = Hierarchy()
  98         auth_info = hierarchy.get_auth_info(caller_gid.get_hrn())
  99         key_file = auth_info.get_privkey_filename()
 100         cert_file = auth_info.get_gid_filename()
 101         server = interface.get_server(key_file, cert_file, timeout)
 102         return server
 103
 104
 105     def getCredential(self):
 106         """
 107         Return a valid credential for this interface.
 108         """
 109         type = 'authority'
 110         path = self.config.SFA_DATA_DIR
 111         filename = ".".join([self.interface, self.hrn, type, "cred"])
 112         cred_filename = os.path.join(path,filename)
 113         cred = None
 114         if os.path.isfile(cred_filename):
 115             cred = Credential(filename = cred_filename)
 116             # make sure cred isnt expired
 117             if not cred.get_expiration or \
 118                datetime.datetime.utcnow() < cred.get_expiration():
 119                 return cred.save_to_string(save_parents=True)
 120
 121         # get a new credential
 122         if self.interface in ['registry']:
 123             cred =  self.__getCredentialRaw()
 124         else:
 125             cred =  self.__getCredential()
 126         cred.save_to_file(cred_filename, save_parents=True)
 127
 128         return cred.save_to_string(save_parents=True)
 129
 130
 131     def getDelegatedCredential(self, creds):
 132         """
 133         Attempt to find a credential delegated to us in
 134         the specified list of creds.
 135         """
 136         from sfa.trust.hierarchy import Hierarchy
 137         if creds and not isinstance(creds, list):
 138             creds = [creds]
 139         hierarchy = Hierarchy()
 140
 141         delegated_cred = None
 142         for cred in creds:
 143             if hierarchy.auth_exists(Credential(string=cred).get_gid_caller().get_hrn()):
 144                 delegated_cred = cred
 145                 break
 146         return delegated_cred
 147
 148     def __getCredential(self):
 149         """
 150         Get our credential from a remote registry
 151         """
 152         from sfa.server.registry import Registries
 153         registries = Registries()
 154         registry = registries.get_server(self.hrn, self.key_file, self.cert_file)
 155         cert_string=self.cert.save_to_string(save_parents=True)
 156         # get self credential
 157         self_cred = registry.GetSelfCredential(cert_string, self.hrn, 'authority')
 158         # get credential
 159         cred = registry.GetCredential(self_cred, self.hrn, 'authority')
 160         return Credential(string=cred)
 161
 162     def __getCredentialRaw(self):
 163         """
 164         Get our current credential directly from the local registry.
 165         """
 166
 167         hrn = self.hrn
 168         auth_hrn = self.auth.get_authority(hrn)
 169
 170         # is this a root or sub authority
 171         if not auth_hrn or hrn == self.config.SFA_INTERFACE_HRN:
 172             auth_hrn = hrn
 173         auth_info = self.auth.get_auth_info(auth_hrn)
 174         table = self.SfaTable()
 175         records = table.findObjects({'hrn': hrn, 'type': 'authority+sa'})
 176         if not records:
 177             raise RecordNotFound
 178         record = records[0]
 179         type = record['type']
 180         object_gid = record.get_gid_object()
 181         new_cred = Credential(subject = object_gid.get_subject())
 182         new_cred.set_gid_caller(object_gid)
 183         new_cred.set_gid_object(object_gid)
 184         new_cred.set_issuer_keys(auth_info.get_privkey_filename(), auth_info.get_gid_filename())
 185
 186         r1 = determine_rights(type, hrn)
 187         new_cred.set_privileges(r1)
 188         new_cred.encode()
 189         new_cred.sign()
 190
 191         return new_cred
 192
 193     def loadCredential (self):
 194         """
 195         Attempt to load credential from file if it exists. If it doesnt get
 196         credential from registry.
 197         """
 198
 199         # see if this file exists
 200         # XX This is really the aggregate's credential. Using this is easier than getting
 201         # the registry's credential from iteslf (ssl errors).
 202         filename = self.interface + self.hrn + ".ma.cred"
 203         ma_cred_path = os.path.join(self.config.SFA_DATA_DIR,filename)
 204         try:
 205             self.credential = Credential(filename = ma_cred_path)
 206         except IOError:
 207             self.credential = self.getCredentialFromRegistry()
 208
 209     def get_cached_server_version(self, server):
 210         cache_key = server.url + "-version"
 211         server_version = None
 212         if self.cache:
 213             server_version = self.cache.get(cache_key)
 214         if not server_version:
 215             server_version = server.GetVersion()
 216             # cache version for 24 hours
 217             self.cache.add(cache_key, server_version, ttl= 60*60*24)
 218         return server_version