Merged client and server into a single script.

git-svn-id: http://pexpect.svn.sourceforge.net/svnroot/pexpect/trunk@419 656d521f-e311-0410-88e0-e7920216d269

1 files changed, 340 insertions, 67 deletions

diff --git a/pexpect/examples/bd_client.cgi b/pexpect/examples/bd_client.cgi
index 66341b1..73e7955 100755
--- a/pexpect/examples/bd_client.cgi
+++ b/pexpect/examples/bd_client.cgi
@@ -1,9 +1,339 @@
 #!/usr/bin/env python
-# #sys.path.insert (0,"/var/www/cgi-bin")
-#sys.path.insert (0,"/usr/local/apache/cgi-bin")
+"""Back door shell server
 
-import sys, os, socket, random, string, traceback, cgi
+This exposes a shell terminal on a socket.
 
+    --hostname : sets the remote host name to open an ssh connection to.
+    --username : sets the user name to login with
+    --password : (optional) sets the password to login with
+    --port     : set the local port for the server to listen on
+    --watch    : show the virtual screen after each client request
+
+This project is probably not the most security concious thing I've ever built.
+This should be considered an experimental tool -- at best.
+"""
+import sys,os
+sys.path.insert (0,os.getcwd())
+import socket, random, string, traceback, cgi, time, getopt, getpass, threading
+import pxssh, pexpect, ANSI
+import pxssh, pexpect, ANSI
+
+def exit_with_usage(exit_code=1):
+    print globals()['__doc__']
+    os._exit(exit_code)
+
+def client (command, host='localhost', port=-1):
+    """This sends a request to the server and returns the response.
+    If port is <= 0 then host is assumed to be the filename of a Unix domain socket.
+    If port is greater 0 then host is an inet hostname.
+    """
+    if port <= 0:
+        s = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)
+        s.connect(host)
+    else:
+        s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+        s.connect((host, port))
+    s.send(command)
+    data = s.recv (2500)
+    s.close()
+    return data
+
+def server (hostname, username, password, socket_filename='/tmp/mysock', verbose=False):
+    """This starts and services requests from the client.
+    """
+    if verbose: sys.stdout.write ('server started with pid %d\n' % os.getpid() )
+
+    virtual_screen = ANSI.ANSI (24,80) 
+    child = pxssh.pxssh()
+    child.login (hostname, username, password)
+    if verbose: print 'created shell. command line prompt is', child.PROMPT
+    virtual_screen.write (child.before)
+    virtual_screen.write (child.after)
+
+    if os.path.exists(socket_filename): os.remove(socket_filename)
+    s = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)
+    localhost = '127.0.0.1'
+    s.bind(socket_filename)
+    os.chmod(socket_filename,0777)
+    if verbose: print 'Listen'
+    s.listen(1)
+    #s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+    #localhost = '127.0.0.1'
+    #s.bind((localhost, port))
+    #print 'Listen'
+    #s.listen(1)
+
+    r = roller (0.01, endless_poll, (child, child.PROMPT, virtual_screen))
+    r.start()
+    if verbose: print "screen poll updater started in background thread"
+    sys.stdout.flush()
+    try:
+        while True:
+            conn, addr = s.accept()
+            if verbose: print 'Connected by', addr
+            data = conn.recv(1024)
+            if data[0]!=':':
+                cmd = ':sendline'
+                arg = data.strip()
+            else:
+                request = data.split(' ', 1)
+                if len(request)>1:
+                    cmd = request[0].strip()
+                    arg = request[1].strip()
+                else:
+                    cmd = request[0].strip()
+            if cmd == ':exit':
+                r.cancel()
+                break
+            elif cmd == ':sendline':
+                child.sendline (arg)
+                #child.prompt(timeout=2)
+                time.sleep(0.2)
+                shell_window = str(virtual_screen)
+            elif cmd == ':send' or cmd==':xsend':
+                if cmd==':xsend':
+                    arg = arg.decode("hex")
+                child.send (arg)
+                time.sleep(0.2)
+                shell_window = str(virtual_screen)
+            elif cmd == ':cursor':
+                shell_window = '%x%x' % (virtual_screen.cur_r, virtual_screen.cur_c)
+            elif cmd == ':refresh':
+                shell_window = str(virtual_screen)
+
+            response = []
+            response.append (shell_window)
+            #response = add_cursor_blink (response, row, col)
+            if verbose: print '\n'.join(response)
+            sent = conn.send('\n'.join(response))
+            if sent < len (response):
+                if verbose: print "Sent is too short. Some data was cut off."
+            conn.close()
+    finally:
+        r.cancel()
+        if verbose: print "cleaning up socket"
+        s.close()
+        if os.path.exists(socket_filename): os.remove(socket_filename)
+        if verbose: print "server done!"
+
+class roller (threading.Thread):
+    """This class continuously loops a function in a thread.
+    """
+    def __init__(self, interval, function, args=[], kwargs={}):
+        """The interval parameter defines time between each call to the function.
+        """
+        threading.Thread.__init__(self)
+        self.interval = interval
+        self.function = function
+        self.args = args
+        self.kwargs = kwargs
+        self.finished = threading.Event()
+    def cancel(self):
+        """Stop the roller."""
+        self.finished.set()
+    def run(self):
+        while not self.finished.isSet():
+            # self.finished.wait(self.interval)
+            self.function(*self.args, **self.kwargs)
+
+def endless_poll (child, prompt, screen, refresh_timeout=0.1):
+    """This keeps the screen updated with the output of the child.
+        This runs in a separate thread.
+        See roller class.
+    """
+    #child.logfile_read = screen
+    try:
+        s = child.read_nonblocking(4000, 0.1)
+        screen.write(s)
+    except:
+        pass
+
+def daemonize (stdin='/dev/null', stdout='/dev/null', stderr='/dev/null'):
+    '''This forks the current process into a daemon.
+    Almost none of this is necessary (or advisable) if your daemon 
+    is being started by inetd. In that case, stdin, stdout and stderr are 
+    all set up for you to refer to the network connection, and the fork()s 
+    and session manipulation should not be done (to avoid confusing inetd). 
+    Only the chdir() and umask() steps remain as useful. 
+
+    References:
+        UNIX Programming FAQ
+        1.7 How do I get my program to act like a daemon?
+        http://www.erlenstar.demon.co.uk/unix/faq_2.html#SEC16
+
+        Advanced Programming in the Unix Environment
+        W. Richard Stevens, 1992, Addison-Wesley, ISBN 0-201-56317-7.
+
+    The stdin, stdout, and stderr arguments are file names that
+    will be opened and be used to replace the standard file descriptors
+    in sys.stdin, sys.stdout, and sys.stderr.
+    These arguments are optional and default to /dev/null.
+    Note that stderr is opened unbuffered, so
+    if it shares a file with stdout then interleaved output
+    may not appear in the order that you expect.
+    '''
+
+    # Do first fork.
+    try: 
+        pid = os.fork() 
+        if pid > 0:
+            sys.exit(0)   # Exit first parent.
+    except OSError, e: 
+        sys.stderr.write ("fork #1 failed: (%d) %s\n" % (e.errno, e.strerror) )
+        sys.exit(1)
+
+    # Decouple from parent environment.
+    os.chdir("/") 
+    os.umask(0) 
+    os.setsid() 
+
+    # Do second fork.
+    try: 
+        pid = os.fork() 
+        if pid > 0:
+            sys.exit(0)   # Exit second parent.
+    except OSError, e: 
+        sys.stderr.write ("fork #2 failed: (%d) %s\n" % (e.errno, e.strerror) )
+        sys.exit(1)
+
+    # Now I am a daemon!
+    
+    # Redirect standard file descriptors.
+    si = open(stdin, 'r')
+    so = open(stdout, 'a+')
+    se = open(stderr, 'a+', 0)
+    os.dup2(si.fileno(), sys.stdin.fileno())
+    os.dup2(so.fileno(), sys.stdout.fileno())
+    os.dup2(se.fileno(), sys.stderr.fileno())
+
+    # I now return as the daemon
+    return 0
+
+def random_sid ():
+    a=random.randint(0,65535)
+    b=random.randint(0,65535)
+    return '%04x%04x.sid' % (a,b)
+
+def parse_host_connect_string (hcs):
+    """This parses a host connection string in the form
+    username:password@hostname:port. All fields are options expcet hostname. A
+    dictionary is returned with all four keys. Keys that were not included are
+    set to empty strings ''. Note that if your password has the '@' character
+    then you must backslash escape it.
+    """
+    if '@' in hcs:
+        p = re.compile (r'(?P<username>[^@:]*)(:?)(?P<password>.*)(?!\\)@(?P<hostname>[^:]*):?(?P<port>[0-9]*)')
+    else:
+        p = re.compile (r'(?P<username>)(?P<password>)(?P<hostname>[^:]*):?(?P<port>[0-9]*)')
+    m = p.search (hcs)
+    d = m.groupdict()
+    d['password'] = d['password'].replace('\\@','@')
+    return d
+     
+def pretty_box (s, rows=24, cols=80):
+    """This puts an ASCII text box around the given string.
+    """
+    top_bot = '+' + '-'*cols + '+\n'
+    return top_bot + '\n'.join(['|'+line+'|' for line in s.split('\n')]) + '\n' + top_bot
+    
+def client_cgi ():
+    """This handles the request if this script was called as a cgi.
+    """
+    print "Content-type: text/html;charset=utf-8\r\n"
+    sys.stderr = sys.stdout
+    ajax_mode = False
+    TITLE="Shell"
+    SHELL_OUTPUT=""
+    SID="NOT"
+    try:
+        form = cgi.FieldStorage()
+        if not form.has_key('sid'):
+            SID=random_sid()
+        else:
+            SID=form['sid'].value
+        if form.has_key('ajax'):
+            ajax_mode = True
+            ajax_cmd = form['ajax'].value
+            if ajax_cmd == 'send':
+                command = ':xsend'
+                arg = form['arg'].value.encode('hex')
+                result = client (command + ' ' + arg, '/tmp/mysock')
+                print result
+            elif ajax_cmd == 'refresh':
+                command = ':refresh'
+                result = client (command, '/tmp/mysock')
+                print result
+            elif ajax_cmd == 'cursor':
+                command = ':cursor'
+                result = client (command, '/tmp/mysock')
+                print result
+        elif form.has_key('command'):
+            command = form["command"].value
+            SHELL_OUTPUT = client (command, '/tmp/mysock')
+            print CGISH_HTML % locals()
+        else:
+            print CGISH_HTML % locals()
+    except:
+        tb_dump = traceback.format_exc()
+        if ajax_mode:
+            print str(tb_dump)
+        else:
+            SHELL_OUTPUT=str(tb_dump)
+            print CGISH_HTML % locals()
+
+def server_cli():
+    """This is the command line interface to starting the server.
+    This handles things if the script was not called as a CGI
+    (if you run it from the command line).
+    """
+    try:
+        optlist, args = getopt.getopt(sys.argv[1:], 'h?d', ['help','h','?', 'hostname=', 'username=', 'password=', 'port=', 'watch'])
+    except Exception, e:
+        print str(e)
+        exit_with_usage()
+
+    command_line_options = dict(optlist)
+    options = dict(optlist)
+    # There are a million ways to cry for help. These are but a few of them.
+    if [elem for elem in command_line_options if elem in ['-h','--h','-?','--?','--help']]:
+        exit_with_usage(0)
+  
+    hostname = "127.0.0.1"
+    #port = 1664
+    username = os.getenv('USER')
+    password = ""
+    daemon_mode = False
+    if '-d' in options:
+        daemon_mode = True
+    if '--watch' in options:
+        watch_mode = True
+    else:
+        watch_mode = False
+    if '--hostname' in options:
+        hostname = options['--hostname']
+    if '--port' in options:
+        port = int(options['--port'])
+    if '--username' in options:
+        username = options['--username']
+    if '--password' in options:
+        password = options['--password']
+    else:
+        password = getpass.getpass('password: ')
+   
+    if daemon_mode: 
+        print "daemonizing server"
+        daemonize()
+        #daemonize('/dev/null','/tmp/daemon.log','/tmp/daemon.log')
+
+    server (hostname, username, password)
+
+def main ():
+    if os.getenv('REQUEST_METHOD') is None:
+        server_cli()
+    else:
+        client_cgi()
+
+# It's mostly HTML and Javascript from here on out.
 CGISH_HTML="""<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
 <html>
 <head>
@@ -112,7 +442,6 @@ function query_cursor()
 {
     loadurl('bd_client.cgi?ajax=cursor');
 }
-
 function type_key (chars)
 {
     var ch = '?';
@@ -243,7 +572,7 @@ function KeyCheck(e)
 <body onload="init()">
 <form id="form" name="form" action="/cgi-bin/bd_client.cgi" method="POST">
 <input name="sid" value="%(SID)s" type="hidden">
-<textarea name="screen_text" cols="80" rows="24">%(SHELL_OUTPUT)s</textarea>
+<textarea name="screen_text" cols="81" rows="25">%(SHELL_OUTPUT)s</textarea>
 <hr noshade="1">
 &nbsp;<input name="command" id="command" type="text" size="80"><br>
 <p align="left"> 
@@ -251,7 +580,6 @@ function KeyCheck(e)
 <tr>
 <td width="86%%" align="center">    
     <input name="submit" type="submit" value="Enter">
-    <input name="esc" type="submit" value="ESC">
     <input name="refresh" type="button" value="REFRESH" onclick="refresh_screen()">
     <input name="refresh" type="button" value="CURSOR" onclick="query_cursor()">
     <br>
@@ -326,66 +654,11 @@ function KeyCheck(e)
 </html>
 """
 
-def random_sid ():
-    a=random.randint(0,65535)
-    b=random.randint(0,65535)
-    return 'pxssh%04x%04x' % (a,b)
-
-def bd_client (command, host='localhost', port=-1):
-    """This sends a request to the server and returns the response.
-    If port is less than 0 then host is assumed
-    to be the filename of a Unix domain socket.
-    """
-    if port < 0:
-        s = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)
-        s.connect(host)
-    else:
-        s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
-        s.connect((host, port))
-    s.send(command)
-    data = s.recv (2500)
-    s.close()
-    return data
-
-print "Content-type: text/html;charset=utf-8\r\n"
-sys.stderr = sys.stdout
-ajax_mode = False
-TITLE="Shell"
-SHELL_OUTPUT=""
-SID="NOT"
-try:
-    form = cgi.FieldStorage()
-    if not form.has_key('sid'):
-        SID=random_sid()
-    else:
-        SID=form['sid'].value
-    if form.has_key('ajax'):
-        ajax_mode = True
-        ajax_cmd = form['ajax'].value
-        if ajax_cmd == 'send':
-            command = ':xsend'
-            arg = form['arg'].value.encode('hex')
-            result = bd_client (command + ' ' + arg, "/tmp/mysock")
-            print result
-        elif ajax_cmd == 'refresh':
-            command = ':refresh'
-            result = bd_client (command, "/tmp/mysock")
-            print result
-        elif ajax_cmd == 'cursor':
-            command = ':cursor'
-            result = bd_client (command, "/tmp/mysock")
-            print result
-    elif form.has_key('command'):
-        command = form["command"].value
-        SHELL_OUTPUT = bd_client (command, "/tmp/mysock")
-        print CGISH_HTML % locals()
-    else:
-        print CGISH_HTML % locals()
-except:
-    tb_dump = traceback.format_exc()
-    if ajax_mode:
+if __name__ == "__main__":
+    try:
+        main()
+    except Exception, e:
+        print str(e)
+        tb_dump = traceback.format_exc()
         print str(tb_dump)
-    else:
-        SHELL_OUTPUT=str(tb_dump)
-        print CGISH_HTML % locals()