111 lines
2.3 KiB
Python
111 lines
2.3 KiB
Python
|
# Minimal interface to the Internet telnet protocol.
|
||
|
|
#
|
||
|
|
# *** modified to use threads ***
|
||
|
|
#
|
||
|
|
# It refuses all telnet options and does not recognize any of the other
|
||
|
|
# telnet commands, but can still be used to connect in line-by-line mode.
|
||
|
|
# It's also useful to play with a number of other services,
|
||
|
|
# like time, finger, smtp and even ftp.
|
||
|
|
#
|
||
|
|
# Usage: telnet host [port]
|
||
|
|
#
|
||
|
|
# The port may be a service name or a decimal port number;
|
||
|
|
# it defaults to 'telnet'.
|
||
|
|
|
||
|
|
|
||
|
|
import sys, os, time
|
||
|
|
from socket import *
|
||
|
|
import thread
|
||
|
|
|
||
|
|
BUFSIZE = 8*1024
|
||
|
|
|
||
|
|
# Telnet protocol characters
|
||
|
|
|
||
|
|
IAC = chr(255) # Interpret as command
|
||
|
|
DONT = chr(254)
|
||
|
|
DO = chr(253)
|
||
|
|
WONT = chr(252)
|
||
|
|
WILL = chr(251)
|
||
|
|
|
||
|
|
def main():
|
||
|
|
host = sys.argv[1]
|
||
|
|
try:
|
||
|
|
hostaddr = gethostbyname(host)
|
||
|
|
except error:
|
||
|
|
sys.stderr.write(sys.argv[1] + ': bad host name\n')
|
||
|
|
sys.exit(2)
|
||
|
|
#
|
||
|
|
if len(sys.argv) > 2:
|
||
|
|
servname = sys.argv[2]
|
||
|
|
else:
|
||
|
|
servname = 'telnet'
|
||
|
|
#
|
||
|
|
if '0' <= servname[:1] <= '9':
|
||
|
|
port = eval(servname)
|
||
|
|
else:
|
||
|
|
try:
|
||
|
|
port = getservbyname(servname, 'tcp')
|
||
|
|
except error:
|
||
|
|
sys.stderr.write(servname + ': bad tcp service name\n')
|
||
|
|
sys.exit(2)
|
||
|
|
#
|
||
|
|
s = socket(AF_INET, SOCK_STREAM)
|
||
|
|
#
|
||
|
|
try:
|
||
|
|
s.connect(host, port)
|
||
|
|
except error, msg:
|
||
|
|
sys.stderr.write('connect failed: ' + `msg` + '\n')
|
||
|
|
sys.exit(1)
|
||
|
|
#
|
||
|
|
thread.start_new(child, (s,))
|
||
|
|
parent(s)
|
||
|
|
|
||
|
|
def parent(s):
|
||
|
|
# read socket, write stdout
|
||
|
|
iac = 0 # Interpret next char as command
|
||
|
|
opt = '' # Interpret next char as option
|
||
|
|
while 1:
|
||
|
|
data, dummy = s.recvfrom(BUFSIZE)
|
||
|
|
if not data:
|
||
|
|
# EOF -- exit
|
||
|
|
sys.stderr.write( '(Closed by remote host)\n')
|
||
|
|
thread.exit_prog(1)
|
||
|
|
cleandata = ''
|
||
|
|
for c in data:
|
||
|
|
if opt:
|
||
|
|
print ord(c)
|
||
|
|
print '(replying: ' + `opt+c` + ')'
|
||
|
|
s.send(opt + c)
|
||
|
|
opt = ''
|
||
|
|
elif iac:
|
||
|
|
iac = 0
|
||
|
|
if c == IAC:
|
||
|
|
cleandata = cleandata + c
|
||
|
|
elif c in (DO, DONT):
|
||
|
|
if c == DO: print '(DO)',
|
||
|
|
else: print '(DONT)',
|
||
|
|
opt = IAC + WONT
|
||
|
|
elif c in (WILL, WONT):
|
||
|
|
if c == WILL: print '(WILL)',
|
||
|
|
else: print '(WONT)',
|
||
|
|
opt = IAC + DONT
|
||
|
|
else:
|
||
|
|
print '(command)', ord(c)
|
||
|
|
elif c == IAC:
|
||
|
|
iac = 1
|
||
|
|
print '(IAC)',
|
||
|
|
else:
|
||
|
|
cleandata = cleandata + c
|
||
|
|
sys.stdout.write(cleandata)
|
||
|
|
sys.stdout.flush()
|
||
|
|
## print 'Out:', `cleandata`
|
||
|
|
|
||
|
|
def child(s):
|
||
|
|
# read stdin, write socket
|
||
|
|
while 1:
|
||
|
|
line = sys.stdin.readline()
|
||
|
|
## print 'Got:', `line`
|
||
|
|
s.send(line)
|
||
|
|
|
||
|
|
main()
|