implement daemon

shadowsocks/daemon.py

@@ -0,0 +1,173 @@
+#!/usr/bin/python
+# -*- coding: utf-8 -*-
+
+# Copyright (c) 2014 clowwindy
+#
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to deal
+# in the Software without restriction, including without limitation the rights
+# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+#
+# The above copyright notice and this permission notice shall be included in
+# all copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+# SOFTWARE.
+
+from __future__ import absolute_import, division, print_function, \
+    with_statement
+
+import os
+import sys
+import logging
+import signal
+import time
+from shadowsocks import common
+
+# this module is ported from ShadowVPN daemon.c
+
+
+def daemon_exec(config):
+    if 'daemon' in config:
+        if os.name != 'posix':
+            raise Exception('daemon mode is only supported in unix')
+        command = config['daemon']
+        if not command:
+            command = 'start'
+        pid_file = config['pid-file']
+        log_file = config['log-file']
+        command = common.to_str(command)
+        pid_file = common.to_str(pid_file)
+        log_file = common.to_str(log_file)
+        if command == 'start':
+            daemon_start(pid_file, log_file)
+        elif command == 'stop':
+            daemon_stop(pid_file)
+            # always exit after daemon_stop
+            sys.exit(0)
+        elif command == 'restart':
+            daemon_stop(pid_file)
+            daemon_start(pid_file, log_file)
+        else:
+            raise Exception('unsupported daemon command %s' % command)
+
+
+def write_pid_file(pid_file, pid):
+    import fcntl
+    import stat
+
+    try:
+        fd = os.open(pid_file, os.O_RDWR | os.O_CREAT,
+                     stat.S_IRUSR | stat.S_IWUSR)
+    except OSError as e:
+        logging.error(e)
+        return -1
+    flags = fcntl.fcntl(fd, fcntl.F_GETFD)
+    assert flags != -1
+    flags |= fcntl.FD_CLOEXEC
+    r = fcntl.fcntl(fd, fcntl.F_SETFD, flags)
+    assert r != -1
+    # There is no platform independent way to implement fcntl(fd, F_SETLK, &fl)
+    # via fcntl.fcntl. So use lockf instead
+    try:
+        fcntl.lockf(fd, fcntl.LOCK_EX | fcntl.LOCK_NB, 0, 0, os.SEEK_SET)
+    except IOError:
+        r = os.read(fd, 32)
+        if r:
+            logging.error('already started at pid %s' % common.to_str(r))
+        else:
+            logging.error('already started')
+        os.close(fd)
+        return -1
+    os.ftruncate(fd, 0)
+    os.write(fd, common.to_bytes(str(pid)))
+    return 0
+
+
+def freopen(f, mode, stream):
+    oldf = open(f, mode)
+    oldfd = oldf.fileno()
+    newfd = stream.fileno()
+    os.close(newfd)
+    os.dup2(oldfd, newfd)
+
+
+def daemon_start(pid_file, log_file):
+    # fork only once because we are sure parent will exit
+    pid = os.fork()
+    assert pid != -1
+
+    def handle_exit(signum, _):
+        sys.exit(0)
+
+    if pid > 0:
+        # parent waits for its child
+        signal.signal(signal.SIGINT, handle_exit)
+        time.sleep(5)
+        sys.exit(0)
+
+    # child signals its parent to exit
+    ppid = os.getppid()
+    pid = os.getpid()
+    if write_pid_file(pid_file, pid) != 0:
+        os.kill(ppid, signal.SIGINT)
+        sys.exit(1)
+
+    print('started')
+    os.kill(ppid, signal.SIGINT)
+
+    sys.stdin.close()
+    freopen(log_file, 'a', sys.stdout)
+    freopen(log_file, 'a', sys.stderr)
+
+
+def daemon_stop(pid_file):
+    import errno
+    try:
+        with open(pid_file) as f:
+            buf = f.read()
+            pid = common.to_str(buf)
+            if not buf:
+                logging.error('not running')
+    except IOError as e:
+        logging.error(e)
+        if e.errno == errno.ENOENT:
+            # always exit 0 if we are sure daemon is not running
+            logging.error('not running')
+            return
+        sys.exit(1)
+    pid = int(pid)
+    if pid > 0:
+        try:
+            os.kill(pid, signal.SIGTERM)
+        except OSError as e:
+            if e.errno == errno.ESRCH:
+                logging.error('not running')
+                # always exit 0 if we are sure daemon is not running
+                return
+            logging.error(e)
+            sys.exit(1)
+    else:
+        logging.error('pid is not positive: %d', pid)
+
+    # sleep for maximum 10s
+    for i in range(0, 200):
+        try:
+            # query for the pid
+            os.kill(pid, 0)
+        except OSError as e:
+            if e.errno == errno.ESRCH:
+                break
+        time.sleep(0.05)
+    else:
+        logging.error('timed out when stopping pid %d', pid)
+        sys.exit(1)
+    print('stopped')
+    os.unlink(pid_file)

shadowsocks/local.py

@@ -30,7 +30,8 @@ import logging
 import signal
 
 sys.path.insert(0, os.path.join(os.path.dirname(__file__), '../'))
-from shadowsocks import utils, encrypt, eventloop, tcprelay, udprelay, asyncdns
+from shadowsocks import utils, daemon, encrypt, eventloop, tcprelay, udprelay,\
+    asyncdns
 
 
 def main():
@@ -44,6 +45,8 @@ def main():
 
     config = utils.get_config(True)
 
+    daemon.daemon_exec(config)
+
     utils.print_shadowsocks()
 
     encrypt.try_cipher(config['password'], config['method'])

shadowsocks/server.py

@@ -30,7 +30,8 @@ import logging
 import signal
 
 sys.path.insert(0, os.path.join(os.path.dirname(__file__), '../'))
-from shadowsocks import utils, encrypt, eventloop, tcprelay, udprelay, asyncdns
+from shadowsocks import utils, daemon, encrypt, eventloop, tcprelay, udprelay,\
+    asyncdns
 
 
 def main():
@@ -38,6 +39,8 @@ def main():
 
     config = utils.get_config(False)
 
+    daemon.daemon_exec(config)
+
     utils.print_shadowsocks()
 
     if config['port_password']:

shadowsocks/utils.py

@@ -70,9 +70,9 @@ def find_config():
 
 def check_config(config):
     if config.get('local_address', '') in [b'0.0.0.0']:
-        logging.warn('warning: local set to listen 0.0.0.0, which is not safe')
+        logging.warn('warning: local set to listen on 0.0.0.0, it\'s not safe')
     if config.get('server', '') in [b'127.0.0.1', b'localhost']:
-        logging.warn('warning: server set to listen %s:%s, are you sure?' %
+        logging.warn('warning: server set to listen on %s:%s, are you sure?' %
                      (config['server'], config['server_port']))
     if (config.get('method', '') or '').lower() == b'table':
         logging.warn('warning: table is not safe; please use a safer cipher, '
@@ -96,11 +96,11 @@ def get_config(is_local):
     logging.basicConfig(level=logging.INFO,
                         format='%(levelname)-s: %(message)s')
     if is_local:
-        shortopts = 'hs:b:p:k:l:m:c:t:vq'
+        shortopts = 'hd:s:b:p:k:l:m:c:t:vq'
-        longopts = ['fast-open']
+        longopts = ['help', 'fast-open', 'pid-file=', 'log-file=']
     else:
-        shortopts = 'hs:p:k:m:c:t:vq'
+        shortopts = 'hd:s:p:k:m:c:t:vq'
-        longopts = ['fast-open', 'workers=']
+        longopts = ['help', 'fast-open', 'pid-file=', 'log-file=', 'workers=']
     try:
         config_path = find_config()
         optlist, args = getopt.getopt(sys.argv[1:], shortopts, longopts)
@@ -146,12 +146,18 @@ def get_config(is_local):
                 config['fast_open'] = True
             elif key == '--workers':
                 config['workers'] = int(value)
-            elif key == '-h':
+            elif key in ('-h', '--help'):
                 if is_local:
                     print_local_help()
                 else:
                     print_server_help()
                 sys.exit(0)
+            elif key == '-d':
+                config['daemon'] = value
+            elif key == '--pid-file':
+                config['pid-file'] = value
+            elif key == '--log-file':
+                config['log-file'] = value
             elif key == '-q':
                 v_count -= 1
                 config['verbose'] = v_count
@@ -171,6 +177,9 @@ def get_config(is_local):
     config['timeout'] = int(config.get('timeout', 300))
     config['fast_open'] = config.get('fast_open', False)
     config['workers'] = config.get('workers', 1)
+    config['pid-file'] = config.get('pid-file', '/var/run/shadowsocks.pid')
+    config['log-file'] = config.get('log-file', '/var/log/shadowsocks.log')
+    config['workers'] = config.get('workers', 1)
     config['verbose'] = config.get('verbose', False)
     config['local_address'] = config.get('local_address', '127.0.0.1')
     config['local_port'] = config.get('local_port', 1080)
@@ -231,21 +240,29 @@ def print_help(is_local):
 def print_local_help():
     print('''usage: sslocal [-h] -s SERVER_ADDR [-p SERVER_PORT]
                [-b LOCAL_ADDR] [-l LOCAL_PORT] -k PASSWORD [-m METHOD]
-               [-t TIMEOUT] [-c CONFIG] [--fast-open] [-v] [-q]
+               [-t TIMEOUT] [-c CONFIG] [--fast-open] [-v] -[d] [-q]
+A fast tunnel proxy that helps you bypass firewalls.
 
-optional arguments:
+You can supply configurations via either config file or command line arguments.
-  -h, --help            show this help message and exit
+
-  -s SERVER_ADDR        server address
+Proxy options:
-  -p SERVER_PORT        server port, default: 8388
+  -h, --help             show this help message and exit
-  -b LOCAL_ADDR         local binding address, default: 127.0.0.1
+  -c CONFIG              path to config file
-  -l LOCAL_PORT         local port, default: 1080
+  -s SERVER_ADDR         server address
-  -k PASSWORD           password
+  -p SERVER_PORT         server port, default: 8388
-  -m METHOD             encryption method, default: aes-256-cfb
+  -b LOCAL_ADDR          local binding address, default: 127.0.0.1
-  -t TIMEOUT            timeout in seconds, default: 300
+  -l LOCAL_PORT          local port, default: 1080
-  -c CONFIG             path to config file
+  -k PASSWORD            password
-  --fast-open           use TCP_FASTOPEN, requires Linux 3.7+
+  -m METHOD              encryption method, default: aes-256-cfb
-  -v, -vv               verbose mode
+  -t TIMEOUT             timeout in seconds, default: 300
-  -q, -qq               quiet mode, only show warnings/errors
+  --fast-open            use TCP_FASTOPEN, requires Linux 3.7+
+
+General options:
+  -d start/stop/restart  daemon mode
+  --pid-file PID_FILE    pid file for daemon mode
+  --log-file LOG_FILE    log file for daemon mode
+  -v, -vv                verbose mode
+  -q, -qq                quiet mode, only show warnings/errors
 
 Online help: <https://github.com/clowwindy/shadowsocks>
 ''')
@@ -254,20 +271,28 @@ Online help: <https://github.com/clowwindy/shadowsocks>
 def print_server_help():
     print('''usage: ssserver [-h] [-s SERVER_ADDR] [-p SERVER_PORT] -k PASSWORD
                 -m METHOD [-t TIMEOUT] [-c CONFIG] [--fast-open]
-                [--workers WORKERS] [-v] [-q]
+                [--workers WORKERS] [-v] [-d start] [-q]
+A fast tunnel proxy that helps you bypass firewalls.
 
-optional arguments:
+You can supply configurations via either config file or command line arguments.
-  -h, --help            show this help message and exit
+
-  -s SERVER_ADDR        server address, default: 0.0.0.0
+Proxy options:
-  -p SERVER_PORT        server port, default: 8388
+  -h, --help             show this help message and exit
-  -k PASSWORD           password
+  -c CONFIG              path to config file
-  -m METHOD             encryption method, default: aes-256-cfb
+  -s SERVER_ADDR         server address, default: 0.0.0.0
-  -t TIMEOUT            timeout in seconds, default: 300
+  -p SERVER_PORT         server port, default: 8388
-  -c CONFIG             path to config file
+  -k PASSWORD            password
-  --fast-open           use TCP_FASTOPEN, requires Linux 3.7+
+  -m METHOD              encryption method, default: aes-256-cfb
-  --workers WORKERS     number of workers, available on Unix/Linux
+  -t TIMEOUT             timeout in seconds, default: 300
-  -v, -vv               verbose mode
+  --fast-open            use TCP_FASTOPEN, requires Linux 3.7+
-  -q, -qq               quiet mode, only show warnings/errors
+  --workers WORKERS      number of workers, available on Unix/Linux
+
+General options:
+  -d start/stop/restart  daemon mode
+  --pid-file PID_FILE    pid file for daemon mode
+  --log-file LOG_FILE    log file for daemon mode
+  -v, -vv                verbose mode
+  -q, -qq                quiet mode, only show warnings/errors
 
 Online help: <https://github.com/clowwindy/shadowsocks>
 ''')