#!/usr/bin/env python """ A pure python ping implementation using raw socket. Note that ICMP messages can only be sent from processes running as root. Derived from ping.c distributed in Linux's netkit. That code is copyright (c) 1989 by The Regents of the University of California. That code is in turn derived from code written by Mike Muuss of the US Army Ballistic Research Laboratory in December, 1983 and placed in the public domain. They have my thanks. Bugs are naturally mine. I'd be glad to hear about them. There are certainly word - size dependenceies here. Copyright (c) Matthew Dixon Cowles, <http://www.visi.com/~mdc/>. Distributable under the terms of the GNU General Public License version 2. Provided with no warranties of any sort. Original Version from Matthew Dixon Cowles: -> ftp://ftp.visi.com/users/mdc/ping.py Rewrite by Jens Diemer: -> http://www.python-forum.de/post-69122.html#69122 Rewrite by George Notaras: -> http://www.g-loaded.eu/2009/10/30/python-ping/ Fork by Pierre Bourdon: -> http://bitbucket.org/delroth/python-ping/ Revision history ~~~~~~~~~~~~~~~~ November 22, 1997 ----------------- Initial hack. Doesn't do much, but rather than try to guess what features I (or others) will want in the future, I've only put in what I need now. December 16, 1997 ----------------- For some reason, the checksum bytes are in the wrong order when this is run under Solaris 2.X for SPARC but it works right under Linux x86. Since I don't know just what's wrong, I'll swap the bytes always and then do an htons(). December 4, 2000 ---------------- Changed the struct.pack() calls to pack the checksum and ID as unsigned. My thanks to Jerome Poincheval for the fix. May 30, 2007 ------------ little rewrite by Jens Diemer: - change socket asterisk import to a normal import - replace time.time() with time.clock() - delete "return None" (or change to "return" only) - in checksum() rename "str" to "source_string" November 8, 2009 ---------------- Improved compatibility with GNU/Linux systems. Fixes by: * George Notaras -- http://www.g-loaded.eu Reported by: * Chris Hallman -- http://cdhallman.blogspot.com Changes in this release: - Re-use time.time() instead of time.clock(). The 2007 implementation worked only under Microsoft Windows. Failed on GNU/Linux. time.clock() behaves differently under the two OSes.  http://docs.python.org/library/time.html#time.clock September 25, 2010 ------------------ Little modifications by Georgi Kolev: - Added quiet_ping function. - returns percent lost packages, max round trip time, avrg round trip time - Added packet size to verbose_ping & quiet_ping functions. - Bump up version to 0.2 """ __version__ = "0.2" import os import select import socket import struct import sys import time # From /usr/include/linux/icmp.h; your milage may vary. ICMP_ECHO_REQUEST = 8 # Seems to be the same on Solaris. def checksum(source_string): """ I'm not too confident that this is right but testing seems to suggest that it gives the same answers as in_cksum in ping.c """ sum = 0 count_to = (len(source_string) / 2) * 2 for count in xrange(0, count_to, 2): this = ord(source_string[count + 1]) * 256 + ord(source_string[count]) sum = sum + this sum = sum & 0xffffffff # Necessary? if count_to < len(source_string): sum = sum + ord(source_string[len(source_string) - 1]) sum = sum & 0xffffffff # Necessary? sum = (sum >> 16) + (sum & 0xffff) sum = sum + (sum >> 16) answer = ~sum answer = answer & 0xffff # Swap bytes. Bugger me if I know why. answer = answer >> 8 | (answer << 8 & 0xff00) return answer def receive_one_ping(my_socket, id, timeout): """ Receive the ping from the socket. """ time_left = timeout while True: started_select = time.time() what_ready = select.select([my_socket], , , time_left) how_long_in_select = (time.time() - started_select) if what_ready == : # Timeout return time_received = time.time() received_packet, addr = my_socket.recvfrom(1024) icmpHeader = received_packet[20:28] type, code, checksum, packet_id, sequence = struct.unpack( "bbHHh", icmpHeader ) if packet_id == id: bytes = struct.calcsize("d") time_sent = struct.unpack("d", received_packet[28:28 + bytes]) return time_received - time_sent time_left = time_left - how_long_in_select if time_left <= 0: return def send_one_ping(my_socket, dest_addr, id, psize): """ Send one ping to the given >dest_addr<. """ dest_addr = socket.gethostbyname(dest_addr) # Remove header size from packet size psize = psize - 8 # Header is type (8), code (8), checksum (16), id (16), sequence (16) my_checksum = 0 # Make a dummy heder with a 0 checksum. header = struct.pack("bbHHh", ICMP_ECHO_REQUEST, 0, my_checksum, id, 1) bytes = struct.calcsize("d") data = (psize - bytes) * "Q" data = struct.pack("d", time.time()) + data # Calculate the checksum on the data and the dummy header. my_checksum = checksum(header + data) # Now that we have the right checksum, we put that in. It's just easier # to make up a new header than to stuff it into the dummy. header = struct.pack( "bbHHh", ICMP_ECHO_REQUEST, 0, socket.htons(my_checksum), id, 1 ) packet = header + data my_socket.sendto(packet, (dest_addr, 1)) # Don't know about the 1 def do_one(dest_addr, timeout, psize): """ Returns either the delay (in seconds) or none on timeout. """ icmp = socket.getprotobyname("icmp") try: my_socket = socket.socket(socket.AF_INET, socket.SOCK_RAW, icmp) except socket.error, (errno, msg): if errno == 1: # Operation not permitted msg = msg + ( " - Note that ICMP messages can only be sent from processes" " running as root." ) raise socket.error(msg) raise # raise the original error my_id = os.getpid() & 0xFFFF send_one_ping(my_socket, dest_addr, my_id, psize) delay = receive_one_ping(my_socket, my_id, timeout) my_socket.close() return delay def verbose_ping(dest_addr, timeout = 2, count = 4, psize = 64): """ Send `count' ping with `psize' size to `dest_addr' with the given `timeout' and display the result. """ for i in xrange(count): print "ping %s with ..." % dest_addr, try: delay = do_one(dest_addr, timeout, psize) except socket.gaierror, e: print "failed. (socket error: '%s')" % e break if delay == None: print "failed. (timeout within %ssec.)" % timeout else: delay = delay * 1000 print "get ping in %0.4fms" % delay print def quiet_ping(dest_addr, timeout = 2, count = 4, psize = 64): """ Send `count' ping with `psize' size to `dest_addr' with the given `timeout' and display the result. Returns `percent' lost packages, `max' round trip time and `avrg' round trip time. """ mrtt = None artt = None lost = 0 plist =  for i in xrange(count): try: delay = do_one(dest_addr, timeout, psize) except socket.gaierror, e: print "failed. (socket error: '%s')" % e break if delay != None: delay = delay * 1000 plist.append(delay) # Find lost package percent percent_lost = 100 - (len(plist) * 100 / count) # Find max and avg round trip time if plist: mrtt = max(plist) artt = sum(plist) / len(plist) return percent_lost, mrtt, artt if __name__ == '__main__': #verbose_ping("heise.de") #verbose_ping("google.com") #verbose_ping("a-test-url-taht-is-not-available.com") verbose_ping("www.xd.com") print quiet_ping("www.xd.com",count=10)
特邀博文 / 软件工程师 Pierric Cistac；研究员 Victor Sanh；技术主管 Anthony Moi，来自 Hugging Face
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