source: fedd/federation/server.py @ dc49681

#!/usr/local/bin/python

import sys

from BaseHTTPServer import BaseHTTPRequestHandler

from ZSI import Fault, ParseException, FaultFromNotUnderstood, \
    FaultFromZSIException, FaultFromException, ParsedSoap, SoapWriter

from M2Crypto import SSL
from M2Crypto.SSL.SSLServer import ThreadingSSLServer
import xmlrpclib

from deter import fedid

# ZSI uses a deprecated multifile interface.  This shuts the warning system up.
from warnings import filterwarnings
filterwarnings("ignore", ".*multifile.*", DeprecationWarning, "ZSI")

try:
    from fedd_services import ns0
except ImportError:
    from fedd_server import ns0

from service_error import *

import os.path

import logging
import traceback

# The SSL server here is based on the implementation described at
# http://www.xml.com/pub/a/ws/2004/01/20/salz.html

# Turn off the matching of hostname to certificate ID
SSL.Connection.clientPostConnectionCheck = None

class server(ThreadingSSLServer):
    """
    Interface the fedd services to the XMLRPC and SOAP interfaces
    """
    def __init__(self, ME, handler, ssl_ctx, impl, debug=False):
        """
        Create an SSL server that handles the transport in handler using the
        credentials in ssl_ctx, and interfacing to the implementation of fedd
        services in fedd.  ME is the host port pair on which to bind.
        """
        ThreadingSSLServer.__init__(self, ME, handler, ssl_ctx)
        self.impl = impl
        self.soap_methods = impl.soap_services
        self.xmlrpc_methods = impl.xmlrpc_services
        self.get_handler = impl.get_handler
        self.log = logging.getLogger("fedd")
        if debug: self.handle_error = self.handle_error_debug
        else: self.handle_error = self.handle_error_standard

    def handle_error_debug(self, request=None, client_address=None):
        print '-'*40
        traceback.print_exc()
        print '-'*40


    def handle_error_standard(self, request=None, address=None):
        """
        The default SSLServer prints a stack trace here.  This is a little
        friendlier.
        """
        if request or address:
            self.log.warn("[fedd] Error on incoming connection: %s %s" % \
                    (request or "", address or ""))
        else:
            self.log.warn("[fedd] Error on incoming connection " + \
                    "(Likely SSL error)")

class soap_handler(BaseHTTPRequestHandler):
    """
    Standard connection between SOAP and the fedd services in impl.

    Much of this is boilerplate from 
    http://www.xml.com/pub/a/ws/2004/01/20/salz.html
    """
    server_version = "ZSI/2.0 fedd/0.1 " + BaseHTTPRequestHandler.server_version

    def send_xml(self, text, code=200):
        """Send an XML document as reply"""
        self.send_response(code)
        self.send_header('Content-type', 'text/xml; charset="utf-8"')
        self.send_header('Content-Length', str(len(text)))
        self.end_headers()
        self.wfile.write(text)
        self.wfile.flush()
        self.request.socket.close()

    def send_fault(self, f, code=500):
        """Send a SOAP encoded fault as reply"""
        self.send_xml(f.AsSOAP(processContents="lax"), code)

    def check_headers(self, ps):
        """Send a fault for any required envelope headers"""
        for (uri, localname) in ps.WhatMustIUnderstand():
            self.send_fault(FaultFromNotUnderstood(uri, lname, 'fedd'))
            return False
        return  True

    def check_method(self, ps):
        """Confirm that this class implements the namespace and SOAP method"""
        root = ps.body_root
        if root.namespaceURI not in self.server.impl.soap_namespaces:
            self.send_fault(Fault(Fault.Client, 
                'Unknown namespace "%s"' % root.namespaceURI))
            return False

        if getattr(root, 'localName', None) == None:
            self.send_fault(Fault(Fault.Client, 'No method"'))
            return False
        return True

    def do_POST(self):
        """Treat an HTTP POST request as a SOAP service call"""
        try:
            cl = int(self.headers['content-length'])
            data = self.rfile.read(cl)
            ps = ParsedSoap(data)
        except ParseException, e:
            self.send_fault(Fault(Fault.Client, str(e)))
            return
        except Exception, e:
            self.send_fault(FaultFromException(e, 0, sys.exc_info()[2]))
            return
        if not self.check_headers(ps): return
        if not self.check_method(ps): return
        try:
            resp = self.soap_dispatch(ps.body_root.localName, ps,
                    fedid(cert=self.request.get_peer_cert()))
        except Fault, f:
            self.send_fault(f)
            resp = None

        if resp != None:
            sw = SoapWriter()
            sw.serialize(resp)
            self.send_xml(str(sw))

    def do_GET(self):
        """
        If a get handler is registered, use that to retrieve data.
        """
        if self.server.get_handler:
            code = 200
            fid = fedid(cert=self.request.get_peer_cert())
            fname, type = self.server.get_handler(self.path, fid)
            if fname:
                try:
                    f = open(fname, "rb")
                    size = os.path.getsize(fname)
                except EnvironmentError, e:
                    code = 404
                    size = 0
            else:
                code = 404
                size = 0
        else:
            code = 404
            size = 0

        self.send_response(code)
        if code == 200:
            if type:
                self.send_header('Content-type', type)
            self.send_header('Content-Length', size)
            self.end_headers()
            bytes = f.read(4096)
            while len(bytes):
                self.wfile.write(bytes)
                bytes = f.read(4096)
            self.wfile.flush()
        self.request.socket.close()


    def log_request(self, code=0, size=0):
        """
        Log request to the fedd logger
        """
        self.server.log.info("Successful SOAP request code %d" % code)

    def soap_dispatch(self, method, req, fid):
        """
        The connection to the implementation, using the  method maps

        The implementation provides a mapping from SOAP method name to the
        method in the implementation that provides the service.
        """
        if self.server.soap_methods.has_key(method):
            try:
                return self.server.soap_methods[method](req, fid)
            except service_error, e:
                de = ns0.faultType_Def(
                        (ns0.faultType_Def.schema,
                            "FeddFaultBody")).pyclass()
                de._code=e.code
                de._errstr=e.code_string()
                de._desc=e.desc
                for p in e.proof:
                    dp = ns0.proofType_Def(ns0.proofType_Def.schema, 
                            "proof").pyclass()
                    dp._prover = p.prover
                    dp._principal = p.principal
                    dp._attribute = p.attribute
                    dp._credential = p.creds_to_certs()
                    if de._proof: de._proof.append(dp)
                    else: de._proof = [dp]
                if  e.is_server_error():
                    raise Fault(Fault.Server, e.code_string(), detail=de)
                else:
                    raise Fault(Fault.Client, e.code_string(), detail=de)
        else:
            raise Fault(Fault.Client, "Unknown method: %s" % method)


class xmlrpc_handler(BaseHTTPRequestHandler):
    """
    Standard connection between XMLRPC and the fedd services in impl.

    Much of this is boilerplate from 
    http://www.xml.com/pub/a/ws/2004/01/20/salz.html
    """
    server_version = "ZSI/2.0 fedd/0.1 " + BaseHTTPRequestHandler.server_version

    def send_xml(self, text, code=200):
        """Send an XML document as reply"""
        self.send_response(code)
        self.send_header('Content-type', 'text/xml; charset="utf-8"')
        self.send_header('Content-Length', str(len(text)))
        self.end_headers()
        self.wfile.write(text)
        self.wfile.flush()
        # Make sure to close the socket when we're done
        self.request.socket.close()

    def do_POST(self):
        """Treat an HTTP POST request as an XMLRPC service call"""
        # NB: XMLRPC faults are not HTTP errors, so the code is always 200,
        # unless an HTTP error occurs, which we don't handle.

        resp = None
        data = None
        method = None
        cl = int(self.headers['content-length'])
        data = self.rfile.read(cl)

        try:
            params, method = xmlrpclib.loads(data)
        except xmlrpclib.ResponseError:
            data = xmlrpclib.dumps(xmlrpclib.Fault("Client", 
                "Malformed request"), methodresponse=True)

        if method != None:
            try:
                resp = self.xmlrpc_dispatch(method, params,
                            fedid(cert=self.request.get_peer_cert()))
                data = xmlrpclib.dumps((resp,), encoding='UTF-8', 
                        methodresponse=True)
            except xmlrpclib.Fault, f:
                data = xmlrpclib.dumps(f, methodresponse=True)
                resp = None

        self.send_xml(data)

    def log_request(self, code=0, size=0):
        """
        Log request to the fedd logger
        """
        self.server.log.info("Successful XMLRPC request code %d" % code)


    def xmlrpc_dispatch(self, method, req, fid):
        """
        The connection to the implementation, using the  method maps

        The implementation provides a mapping from XMLRPC method name to the
        method in the implementation that provides the service.
        """
        if self.server.xmlrpc_methods.has_key(method):
            try:
                return self.server.xmlrpc_methods[method](req, fid)
            except service_error, e:
                raise xmlrpclib.Fault(e.code_string(), e.desc)
        else:
            raise xmlrpclib.Fault(100, "Unknown method: %s" % method)