cryptonas-archive/v0.3.1/bin/CryptoBoxWebserver
2006-12-20 03:29:20 +00:00

362 lines
12 KiB
Python
Executable file

#!/usr/bin/env python
#
# The daemon script to run the CryptoBox webserver.
#
# run the script with "--help" to see all possible paramters
#
#
# Copyright 2006 sense.lab e.V.
#
# This file is part of the CryptoBox.
#
# The CryptoBox is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# The CryptoBox is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with the CryptoBox; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
#
__revision__ = "$Id"
import os, sys
import cryptobox.web.sites
from cryptobox.core.exceptions import *
from optparse import OptionParser
## check python version
(ver_major, ver_minor, ver_sub, ver_desc, ver_subsub) = sys.version_info
if (ver_major < 2) or ((ver_major == 2) and (ver_minor < 4)):
sys.stderr.write("You need a python version >= 2.4\n")
sys.stderr.write("Current version is: %s\n" % sys.version)
sys.exit(1)
## check cherrypy dependency
try:
import cherrypy
except:
sys.stderr.write("Could not import the cherrypy module!\n")
sys.stderr.write("Try 'apt-get install python-cherrypy'.\n")
sys.exit(1)
## check clearsilver dependency
try:
import neo_cgi, neo_util
except:
sys.stderr.write("Could not import the clearsilver module!\n")
sys.stderr.write("Try 'apt-get install python-clearsilver'.\n")
sys.exit(1)
## check configobj dependency
try:
import configobj, validate
except:
sys.stderr.write("Could not import the configobj or validate module!\n")
sys.stderr.write("Try 'apt-get install python-configobj'.\n")
sys.exit(1)
# TODO: change this for the release version [development|production]
SERVER_ENVIRONMENT = "production"
class CryptoBoxWebserver:
'''this class starts the cherrypy webserver and serves the single sites'''
def __init__(self, opts):
self.opts = opts
## check conffile
if not os.access(opts.conffile, os.R_OK) or not os.path.isfile(opts.conffile):
sys.stderr.write("Error: could not read configuration file (%s)\n" % opts.conffile)
sys.exit(1)
## store the absolute path as we will chdir later (for daemons)
self.conffile = os.path.realpath(opts.conffile)
## drop privileges to run the cryptobox without root permissions
self.drop_privileges_temporarily()
## initialize site class
try:
cherrypy.root = cryptobox.web.sites.WebInterfaceSites(self.conffile)
self.website = cherrypy.root
except (CBConfigError,CBEnvironmentError), err_msg:
sys.stderr.write("Error: the CryptoBox is misconfigured - please fix it!\n")
sys.stderr.write("%s\n" % str(err_msg))
sys.exit(1)
## restore privileges, as we need them to connect to a low socket (<1024)
self.restore_privileges()
## expose static content and set options
## beware:
cherrypy.config.update({
"global": {
"server.socket_port" : int(opts.port),
"server.socket_host" : opts.host,
"server.log_to_screen" : not opts.background and opts.verbose,
"server.log_tracebacks" : opts.verbose,
"server.log_request_headers": opts.verbose,
"server.environment": SERVER_ENVIRONMENT,
"server.log_file" : opts.logfile },
"/cryptobox-misc": {
"staticFilter.on" : True,
"staticFilter.dir": os.path.realpath(opts.datadir)},
"/favicon.ico": {
"staticFilter.on" : True,
"staticFilter.file": os.path.realpath(os.path.join(opts.datadir, 'favicon.ico'))}
})
def get_user_info(self):
"""Retrieve the uid, gid and additional groups of the given user
"""
import pwd, grp
user_entry = pwd.getpwuid(self.opts.user)
## get the new uid and gid
pw_uid, pw_gid = user_entry[2], user_entry[3]
## change the owner of the webserver log file
try:
os.chown(self.opts.logfile, pw_uid, pw_gid)
except OSError:
## fail silently
pass
## calculate additional groups of the given user
additional_groups = [ entry[2]
for entry in grp.getgrall()
if pw_uid in entry[3] ]
return (pw_uid, pw_gid, additional_groups)
def drop_privileges_temporarily(self):
"""Temporarily drop privileges.
"""
if self.opts.user is None:
return
(pw_uid, pw_gid, additional_groups) = self.get_user_info()
try:
os.setegid(pw_gid)
os.seteuid(pw_uid)
except OSError, err_msg:
sys.stderr.write("Failed to drop privileges temporarily: %s\n" % err_msg)
def restore_privileges(self):
"""Restore previously temporarily dropped privileges.
"""
if self.opts.user is None:
return
try:
os.setegid(os.getgid())
os.seteuid(os.getuid())
except OSError, err_msg:
sys.stderr.write("Failed to restore privileges: %s\n" % err_msg)
def drop_privileges_permanently(self):
"""Drop all privileges of the current process and acquire the privileges of the
given user instead.
"""
if self.opts.user is None:
return
(pw_uid, pw_gid, additional_groups) = self.get_user_info()
try:
os.setgroups(additional_groups)
os.setregid(pw_gid, pw_gid)
os.setreuid(pw_uid, pw_uid)
except OSError, err_msg:
sys.stderr.write("Failed to drop privileges permanently: %s\n" % err_msg)
def start(self):
try:
cherrypy.server.start(initOnly=True)
self.drop_privileges_permanently()
cherrypy.server.wait_for_http_ready()
except cherrypy._cperror.NotReady, err_msg:
sys.stderr.write("Failed to start CryptoBox: %s\n" % err_msg)
sys.exit(1)
except Exception, err_msg:
if err_msg == "(98, 'Address already in use')":
sys.stderr.write("Failed to start CryptoBox: %s\n" % err_msg)
sys.exit(1)
else:
raise
def fork_to_background():
## this is just copy'n'pasted from http://aspn.activestate.com/ASPN/Cookbook/Python/Recipe/278731
## check the original for exhaustive comments
try:
pid = os.fork()
except OSError, err_msg:
sys.stderr.write("Error: failed to fork cryptobox daemon process!\n")
sys.stderr.write("%s\n" % err_msg)
sys.exit(1)
if pid == 0: # the first child
os.setsid()
try:
pid = os.fork()
except OSError, err_msg:
sys.stderr.write("Error: failed to fork second cryptobox daemon process!\n")
sys.stderr.write("%s\n" % err_msg)
sys.exit(1)
if pid == 0: # the second child
## we do not change the directory - otherwise there seems to be a race condition with the python interpreter loading this script file
#os.chdir(os.path.sep)
os.umask(0)
else:
os._exit(0)
else:
os._exit(0)
def close_open_files():
"""this is only necessary if we want to go into background
we will only close stdin, stdout and stderr
"""
import resource # Resource usage information.
## use the following lines to close all open files (including the log file)
# maxfd = resource.getrlimit(resource.RLIMIT_NOFILE)[1]
# if (maxfd == resource.RLIM_INFINITY):
# maxfd = 1024
maxfd = 2
for fd in range(0, maxfd):
try:
## close all except for stderr - we will redirect it later
if fd != 2:
os.close(fd)
except OSError: # ERROR, fd wasn't open to begin with (ignored)
pass
os.open(os.devnull, os.O_RDWR) # standard input (0)
os.dup2(0, 1) # standard output (1)
def write_pid_file(pid_file):
if os.path.exists(pid_file):
sys.stderr.write(
"Warning: pid file (%s) already exists - overwriting ...\n" % pid_file)
try:
pidf = open(pid_file,"w")
pidf.write(str(os.getpid()))
pidf.close()
except (IOError, OSError), err_msg:
sys.stderr.write(
"Warning: failed to write pid file (%s): %s\n" % (pid_file, err_msg))
## it is just a warning - no need to break
def parseOptions():
import cryptobox
import pwd
version = "%prog" + cryptobox.__version__
parser = OptionParser(version=version)
parser.set_defaults(conffile="/etc/cryptobox-server/cryptobox.conf",
pidfile="/var/run/cryptobox-server/webserver.pid",
background=False,
datadir="/usr/share/cryptobox-server/www-data",
logfile="/var/log/cryptobox-server/webserver.log",
port="8080",
host="",
verbose=True,
user=None)
parser.add_option("-c", "--config", dest="conffile",
help="read configuration from FILE", metavar="FILE")
parser.add_option("","--pidfile", dest="pidfile",
help="write process id to FILE", metavar="FILE")
parser.add_option("-B","", dest="background", action="store_true",
help="run webserver in background (as daemon)")
parser.add_option("-q","", dest="verbose", action="store_false",
help="output only errors")
parser.add_option("","--datadir", dest="datadir", metavar="DIR",
help="set data directory to DIR")
parser.add_option("-p","--port", dest="port", metavar="PORT",
help="listen on PORT")
parser.add_option("-l","--logfile", dest="logfile", metavar="FILE",
help="write webserver log to FILE")
parser.add_option("","--host", dest="host", metavar="HOST",
help="attach to HOST")
parser.add_option("-u","--user", dest="user", metavar="USER",
help="change to USER after starting the webserver")
(options, args) = parser.parse_args()
## we do not expect any remaining arguments
if len(args) != 0:
parser.error("unknown argument: %s" % str(args[0]))
if not ((not os.path.exists(options.logfile) \
and os.access(os.path.dirname(options.logfile), os.W_OK)) \
or os.access(options.logfile, os.W_OK)):
parser.error("could not write to logfile (%s)" % options.logfile)
if not os.path.isdir(options.datadir) or not os.access(options.datadir,os.X_OK):
parser.error("could not access the data directory (%s)" % options.datadir)
try:
if (int(options.port) < 0) or (int(options.port) > 65535):
parser.error("invalid port number: %s" % str(options.port))
except ValueError:
parser.error("invalid port specified (%s) - it must be a number" % (options.port))
if options.user:
try:
try:
## check for the user given as uid
uid = pwd.getpwuid(int(options.user))[2]
except ValueError:
## check for the user given as name
uid = pwd.getpwnam(options.user)[2]
except KeyError:
## invalid user specified
parser.error("invalid user specified (%s)" % options.user)
## we will use the uid
options.user = uid
return options
if __name__ == "__main__":
## process arguments
options = parseOptions()
## set umask to 022 (aka 755) - octal value
os.umask(022)
## initialize the webserver class (before forking to get some error messages)
cbw = CryptoBoxWebserver(options)
## fork to background before cbw.start() - otherwise we lose the socket
if options.background:
fork_to_background()
## start the webserver
try:
cbw.start()
except CBError, err_msg:
sys.stderr.write("Failed to start the CryptoBox webserver!\n")
sys.stderr.write("%s\n" % str(err_msg))
sys.stderr.write("Check the log file for details.\n")
sys.exit(1)
## redirect stderr to the webserver's logfile
if options.background:
## replace stdin and stdout by /dev/null
close_open_files()
## replace stderr by the webserver logfile
os.close(2)
os.open(options.logfile, os.O_APPEND)
## startup went fine - fork is done - now we may write the pid file
## write pid file
write_pid_file(options.pidfile)
def exit_handler(signum, sigframe):
cbw.website.cbox.log.info("Shutting down ...")
cbw.website.cleanup()
try:
os.remove(options.pidfile)
except OSError:
pass
os._exit(0)
## the signal handler gets called by a kill signal (usually in background mode)
import signal
signal.signal(signal.SIGTERM, exit_handler)
## this exit handler gets called by KeyboardInterrupt and similar ones (foreground)
import atexit
atexit.register(exit_handler, None, None)
## this will never exit - one of the above exit handlers will get triggered
cherrypy.server.block()