# $Id$
#
# Copyright (C) 2009--2012  Internet Systems Consortium ("ISC")
#
# Permission to use, copy, modify, and distribute this software for any
# purpose with or without fee is hereby granted, provided that the above
# copyright notice and this permission notice appear in all copies.
#
# THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
# REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
# AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
# INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
# LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
# OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
# PERFORMANCE OF THIS SOFTWARE.
#
# Portions copyright (C) 2007--2008  American Registry for Internet Numbers ("ARIN")
#
# Permission to use, copy, modify, and distribute this software for any
# purpose with or without fee is hereby granted, provided that the above
# copyright notice and this permission notice appear in all copies.
#
# THE SOFTWARE IS PROVIDED "AS IS" AND ARIN DISCLAIMS ALL WARRANTIES WITH
# REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
# AND FITNESS.  IN NO EVENT SHALL ARIN BE LIABLE FOR ANY SPECIAL, DIRECT,
# INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
# LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
# OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
# PERFORMANCE OF THIS SOFTWARE.

"""
RPKI publication control protocol.

Per IETF SIDR WG discussion, this is now separate from the publication
protocol itself.
"""

import logging
import rpki.resource_set
import rpki.x509
import rpki.sql
import rpki.exceptions
import rpki.xml_utils
import rpki.http
import rpki.up_down
import rpki.relaxng
import rpki.sundial
import rpki.log

logger = logging.getLogger(__name__)


class publication_control_namespace(object):
  """
  XML namespace parameters for publication control protocol.
  """

  xmlns = "http://www.hactrn.net/uris/rpki/publication-control/"
  nsmap = { None : xmlns }


class client_elt(rpki.xml_utils.data_elt, rpki.sql.sql_persistent, publication_control_namespace):
  """
  <client/> element.
  """

  element_name = "client"
  attributes = ("action", "tag", "client_handle", "base_uri")
  elements = ("bpki_cert", "bpki_glue")
  booleans = ("clear_replay_protection",)

  sql_template = rpki.sql.template(
    "client",
    "client_id",
    "client_handle",
    "base_uri",
    ("bpki_cert", rpki.x509.X509),
    ("bpki_glue", rpki.x509.X509),
    ("last_cms_timestamp", rpki.sundial.datetime))

  base_uri  = None
  bpki_cert = None
  bpki_glue = None
  last_cms_timestamp = None

  def __repr__(self):
    return rpki.log.log_repr(self, self.client_handle, self.base_uri)

  @property
  @rpki.sql.cache_reference
  def objects(self):
    return rpki.pubd.object_obj.sql_fetch_where(self.gctx, "client_id = %s", (self.client_id,))

  def serve_post_save_hook(self, q_pdu, r_pdu, cb, eb):
    """
    Extra server actions for client_elt.
    """
    actions = []
    if q_pdu.clear_replay_protection:
      actions.append(self.serve_clear_replay_protection)
    def loop(iterator, action):
      action(iterator, eb)
    rpki.async.iterator(actions, loop, cb)

  def serve_clear_replay_protection(self, cb, eb):
    """
    Handle a clear_replay_protection action for this client.
    """
    self.last_cms_timestamp = None
    self.sql_mark_dirty()
    cb()

  def serve_fetch_one_maybe(self):
    """
    Find the client object on which a get, set, or destroy method
    should operate, or which would conflict with a create method.
    """
    return self.sql_fetch_where1(self.gctx, "client_handle = %s", (self.client_handle,))

  def serve_fetch_all(self):
    """
    Find client objects on which a list method should operate.
    """
    return self.sql_fetch_all(self.gctx)

  def check_allowed_uri(self, uri):
    """
    Make sure that a target URI is within this client's allowed URI space.
    """
    if not uri.startswith(self.base_uri):
      raise rpki.exceptions.ForbiddenURI


class report_error_elt(rpki.xml_utils.text_elt, publication_control_namespace):
  """
  <report_error/> element.
  """

  element_name = "report_error"
  attributes = ("tag", "error_code")
  text_attribute = "error_text"

  error_text = None

  @classmethod
  def from_exception(cls, e, tag = None):
    """
    Generate a <report_error/> element from an exception.
    """
    self = cls()
    self.tag = tag
    self.error_code = e.__class__.__name__
    self.error_text = str(e)
    return self

  def __str__(self):
    s = ""
    if getattr(self, "tag", None) is not None:
      s += "[%s] " % self.tag
    s += self.error_code
    if getattr(self, "error_text", None) is not None:
      s += ": " + self.error_text
    return s

  def raise_if_error(self):
    """
    Raise exception associated with this <report_error/> PDU.
    """
    t = rpki.exceptions.__dict__.get(self.error_code)
    if isinstance(t, type) and issubclass(t, rpki.exceptions.RPKI_Exception):
      raise t(getattr(self, "text", None))
    else:
      raise rpki.exceptions.BadPublicationReply("Unexpected response from pubd: %s" % self)


class msg(rpki.xml_utils.msg, publication_control_namespace):
  """
  Publication control PDU.
  """

  ## @var version
  # Protocol version
  version = 1

  ## @var pdus
  # Dispatch table of PDUs for this protocol.
  pdus = dict((x.element_name, x) for x in (client_elt, report_error_elt))

  def serve_top_level(self, gctx, cb):
    """
    Serve one msg PDU.
    """
    if not self.is_query():
      raise rpki.exceptions.BadQuery("Message type is not query")
    r_msg = self.__class__.reply()

    def loop(iterator, q_pdu):

      def fail(e):
        if not isinstance(e, rpki.exceptions.NotFound):
          logger.exception("Exception processing PDU %r", q_pdu)
        r_msg.append(report_error_elt.from_exception(e, q_pdu.tag))
        cb(r_msg)

      try:
        q_pdu.gctx = gctx
        q_pdu.serve_dispatch(r_msg, iterator, fail)
      except (rpki.async.ExitNow, SystemExit):
        raise
      except Exception, e:
        fail(e)

    def done():
      cb(r_msg)

    rpki.async.iterator(self, loop, done)


class sax_handler(rpki.xml_utils.sax_handler):
  """
  SAX handler for publication control protocol.
  """

  pdu = msg
  name = "msg"
  version = "1"


class cms_msg(rpki.x509.XML_CMS_object):
  """
  Class to hold a CMS-signed publication control PDU.
  """

  encoding = "us-ascii"
  schema = rpki.relaxng.publication_control
  saxify = sax_handler.saxify