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 from sfa.trust.auth import Auth
   8 from sfa.trust.certificate import Keypair, Certificate
   9 from sfa.trust.credential import Credential
  10 from sfa.trust.rights import determine_rights
  11
  12 # this is wrong all right, but temporary, will use generic
  13 from sfa.server.xmlrpcapi import XmlrpcApi
  14 import os
  15 import datetime
  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 gets augmented by the generic layer with
  27     (*) an instance of manager (actually a manager module for now)
  28     (*) which in turn holds an instance of a testbed driver
  29     """
  30
  31     def __init__ (self, encoding="utf-8", methods='sfa.methods',
  32                   config = "/etc/sfa/sfa_config.py",
  33                   peer_cert = None, interface = None,
  34                   key_file = None, cert_file = None, cache = None):
  35
  36         XmlrpcApi.__init__ (self, encoding)
  37
  38         # we may be just be documenting the API
  39         if config is None:
  40             return
  41         # Load configuration
  42         self.config = Config(config)
  43         self.credential = None
  44         self.auth = Auth(peer_cert)
  45         self.interface = interface
  46         self.hrn = self.config.SFA_INTERFACE_HRN
  47         self.key_file = key_file
  48         self.key = Keypair(filename=self.key_file)
  49         self.cert_file = cert_file
  50         self.cert = Certificate(filename=self.cert_file)
  51         self.cache = cache
  52         if self.cache is None:
  53             self.cache = Cache()
  54
  55         # load registries
  56         from sfa.server.registry import Registries
  57         self.registries = Registries()
  58
  59         # load aggregates
  60         from sfa.server.aggregate import Aggregates
  61         self.aggregates = Aggregates()
  62
  63         # filled later on by generic/Generic
  64         self.manager=None
  65
  66     # tmp
  67     def get_interface_manager(self, manager_base = 'sfa.managers'):
  68         return self.manager
  69
  70     def get_server(self, interface, cred, timeout=30):
  71         """
  72         Returns a connection to the specified interface. Use the specified
  73         credential to determine the caller and look for the caller's key/cert
  74         in the registry hierarchy cache.
  75         """
  76         from sfa.trust.hierarchy import Hierarchy
  77         if not isinstance(cred, Credential):
  78             cred_obj = Credential(string=cred)
  79         else:
  80             cred_obj = cred
  81         caller_gid = cred_obj.get_gid_caller()
  82         hierarchy = Hierarchy()
  83         auth_info = hierarchy.get_auth_info(caller_gid.get_hrn())
  84         key_file = auth_info.get_privkey_filename()
  85         cert_file = auth_info.get_gid_filename()
  86         server = interface.get_server(key_file, cert_file, timeout)
  87         return server
  88
  89
  90     def getCredential(self):
  91         """
  92         Return a valid credential for this interface.
  93         """
  94         type = 'authority'
  95         path = self.config.SFA_DATA_DIR
  96         filename = ".".join([self.interface, self.hrn, type, "cred"])
  97         cred_filename = os.path.join(path,filename)
  98         cred = None
  99         if os.path.isfile(cred_filename):
 100             cred = Credential(filename = cred_filename)
 101             # make sure cred isnt expired
 102             if not cred.get_expiration or \
 103                datetime.datetime.utcnow() < cred.get_expiration():
 104                 return cred.save_to_string(save_parents=True)
 105
 106         # get a new credential
 107         if self.interface in ['registry']:
 108             cred =  self.__getCredentialRaw()
 109         else:
 110             cred =  self.__getCredential()
 111         cred.save_to_file(cred_filename, save_parents=True)
 112
 113         return cred.save_to_string(save_parents=True)
 114
 115
 116     def getDelegatedCredential(self, creds):
 117         """
 118         Attempt to find a credential delegated to us in
 119         the specified list of creds.
 120         """
 121         from sfa.trust.hierarchy import Hierarchy
 122         if creds and not isinstance(creds, list):
 123             creds = [creds]
 124         hierarchy = Hierarchy()
 125
 126         delegated_cred = None
 127         for cred in creds:
 128             if hierarchy.auth_exists(Credential(string=cred).get_gid_caller().get_hrn()):
 129                 delegated_cred = cred
 130                 break
 131         return delegated_cred
 132
 133     def __getCredential(self):
 134         """
 135         Get our credential from a remote registry
 136         """
 137         from sfa.server.registry import Registries
 138         registries = Registries()
 139         registry = registries.get_server(self.hrn, self.key_file, self.cert_file)
 140         cert_string=self.cert.save_to_string(save_parents=True)
 141         # get self credential
 142         self_cred = registry.GetSelfCredential(cert_string, self.hrn, 'authority')
 143         # get credential
 144         cred = registry.GetCredential(self_cred, self.hrn, 'authority')
 145         return Credential(string=cred)
 146
 147     def __getCredentialRaw(self):
 148         """
 149         Get our current credential directly from the local registry.
 150         """
 151
 152         hrn = self.hrn
 153         auth_hrn = self.auth.get_authority(hrn)
 154
 155         # is this a root or sub authority
 156         if not auth_hrn or hrn == self.config.SFA_INTERFACE_HRN:
 157             auth_hrn = hrn
 158         auth_info = self.auth.get_auth_info(auth_hrn)
 159         table = self.SfaTable()
 160         records = table.findObjects({'hrn': hrn, 'type': 'authority+sa'})
 161         if not records:
 162             raise RecordNotFound
 163         record = records[0]
 164         type = record['type']
 165         object_gid = record.get_gid_object()
 166         new_cred = Credential(subject = object_gid.get_subject())
 167         new_cred.set_gid_caller(object_gid)
 168         new_cred.set_gid_object(object_gid)
 169         new_cred.set_issuer_keys(auth_info.get_privkey_filename(), auth_info.get_gid_filename())
 170
 171         r1 = determine_rights(type, hrn)
 172         new_cred.set_privileges(r1)
 173         new_cred.encode()
 174         new_cred.sign()
 175
 176         return new_cred
 177
 178     def loadCredential (self):
 179         """
 180         Attempt to load credential from file if it exists. If it doesnt get
 181         credential from registry.
 182         """
 183
 184         # see if this file exists
 185         # XX This is really the aggregate's credential. Using this is easier than getting
 186         # the registry's credential from iteslf (ssl errors).
 187         filename = self.interface + self.hrn + ".ma.cred"
 188         ma_cred_path = os.path.join(self.config.SFA_DATA_DIR,filename)
 189         try:
 190             self.credential = Credential(filename = ma_cred_path)
 191         except IOError:
 192             self.credential = self.getCredentialFromRegistry()
 193
 194     def get_cached_server_version(self, server):
 195         cache_key = server.url + "-version"
 196         server_version = None
 197         if self.cache:
 198             server_version = self.cache.get(cache_key)
 199         if not server_version:
 200             server_version = server.GetVersion()
 201             # cache version for 24 hours
 202             self.cache.add(cache_key, server_version, ttl= 60*60*24)
 203         return server_version