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