6 Comments


    1. I see that you effectively back-ported this to Python 2.x (and you removed the comment lines that made it a little more readable). I noted the bug you fixed and pulled that change into the code I have here.

      I feel having a Python 3 version is useful (it’s a minor fork), especially to those of us eagerly moving forward with Python 3.

      Reply

  1. As previously stated, yours is the Python 2 version, while mine is the Python 3 version. I see this repository is also the Python 2 back-port of this. At this point I’m just pulling in your Python 2 changes when I see them. I appreciate you folding my cleanups into your repo there. I don’t expect to be making more modifications to my Python 3 version here except to pull in your changes.

    My goal was to understand the inner workings of ping and accomplish a Python 3 port while adding some functionality. I’ve accomplished that… while learning that pinging natively with Python (or Perl, or any other scripting language) is an exercise in frustration because of OS-level restrictions on raw sockets. Making this simply a wrapper around a pre-existing ping subprocess defeats the purpose of all the good work done here to illuminate how ping works. To call a standalone ping several times a second or more (if one is performing a test such as a multiple traceroute with pings) doesn’t appeal to me… it’s a kluge that ignores the implementation of ping entirely. That said, it’s the sort of solution people are forced to duct tape together in scripts when admin rights are required for simple functions like this.

    Reply
  2. ShadowX

    Hey :) i’ve made some changes to the code…
    * Fixing BUG #4 – competability with python 2.x [tested with 2.7]
    – Packet data building is different for 2.x and 3.x.
    ‘cose of the string/bytes difference.
    * Fixing BUG #10 – the multiple resolv issue.
    – When pinging domain names insted of hosts (for exmaple google.com)
    you can get different IP every time you try to resolv it, we should
    resolv the host only once and stick to that IP.
    * Fixing BUGs #3 #10 – Doing hostname resolv only once.
    * Fixing BUG #14 – Removing all ‘global’ stuff.
    – You should not use globul! Its bad for you…and its not thread safe!
    * Fix – forcing the use of different times on linux/windows for
    more accurate mesurments. (time.time – linux/ time.clock – windows)
    * Adding quiet_ping function – This way we’ll be able to use this script
    as external lib.
    * Changing default timeout to 3s. (1second is not enought)
    * Switching data syze to packet size. It’s easyer for the user to ignore the
    fact that the packet headr is 8b and the datasize 64 will make packet with
    size 72.

    Here’s the full source.


    #!/usr/bin/env python
    # -*- coding: utf-8 -*-

    """
    A pure python ping implementation using raw sockets.

    (This is Python 3 port of https://github.com/jedie/python-ping)
    (Tested and working with python 2.7, should work with 2.6+)

    Note that ICMP messages can only be sent from processes running as root
    (in Windows, you must run this script as 'Administrator').

    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 dependencies here.

    Copyright (c) Matthew Dixon Cowles, .
    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/

    Enhancements by Martin Falatic:
    -> http://www.falatic.com/index.php/39/pinging-with-python

    Enhancements and fixes by Georgi Kolev:
    -> http://github.com/jedie/python-ping/

    Revision history
    ~~~~~~~~~~~~~~~~

    January 26, 2012
    ----------------
    * Fixing BUG #4 - competability with python 2.x [tested with 2.7]
    - Packet data building is different for 2.x and 3.x.
    'cose of the string/bytes difference.
    * Fixing BUG #10 - the multiple resolv issue.
    - When pinging domain names insted of hosts (for exmaple google.com)
    you can get different IP every time you try to resolv it, we should
    resolv the host only once and stick to that IP.
    * Fixing BUGs #3 #10 - Doing hostname resolv only once.
    * Fixing BUG #14 - Removing all 'global' stuff.
    - You should not use globul! Its bad for you...and its not thread safe!
    * Fix - forcing the use of different times on linux/windows for
    more accurate mesurments. (time.time - linux/ time.clock - windows)
    * Adding quiet_ping function - This way we'll be able to use this script
    as external lib.
    * Changing default timeout to 3s. (1second is not enought)
    * Switching data syze to packet size. It's easyer for the user to ignore the
    fact that the packet headr is 8b and the datasize 64 will make packet with
    size 72.

    October 12, 2011
    --------------
    Merged updates from the main project
    -> https://github.com/jedie/python-ping

    September 12, 2011
    --------------
    Bugfixes + cleanup by Jens Diemer
    Tested with Ubuntu + Windows 7

    September 6, 2011
    --------------
    Cleanup by Martin Falatic. Restored lost comments and docs. Improved
    functionality: constant time between pings, internal times consistently
    use milliseconds. Clarified annotations (e.g., in the checksum routine).
    Using unsigned data in IP & ICMP header pack/unpack unless otherwise
    necessary. Signal handling. Ping-style output formatting and stats.

    August 3, 2011
    --------------
    Ported to py3k by Zach Ware. Mostly done by 2to3; also minor changes to
    deal with bytes vs. string changes (no more ord() in checksum() because
    >source_string http://tools.ietf.org/html/rfc791)

    0 1 2 3
    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    |Version| IHL |Type of Service| Total Length |
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    | Identification |Flags| Fragment Offset |
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    | Time to Live | Protocol | Header Checksum |
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    | Source Address |
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    | Destination Address |
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    | Options | Padding |
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

    ===========================================================================
    ICMP Echo / Echo Reply Message header info from RFC792
    -> http://tools.ietf.org/html/rfc792

    0 1 2 3
    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    | Type | Code | Checksum |
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    | Identifier | Sequence Number |
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    | Data ...
    +-+-+-+-+-

    ===========================================================================
    ICMP parameter info:
    -> http://www.iana.org/assignments/icmp-parameters/icmp-parameters.xml

    ===========================================================================
    An example of ping's typical output:

    PING heise.de (193.99.144.80): 56 data bytes
    64 bytes from 193.99.144.80: icmp_seq=0 ttl=240 time=127 ms
    64 bytes from 193.99.144.80: icmp_seq=1 ttl=240 time=127 ms
    64 bytes from 193.99.144.80: icmp_seq=2 ttl=240 time=126 ms
    64 bytes from 193.99.144.80: icmp_seq=3 ttl=240 time=126 ms
    64 bytes from 193.99.144.80: icmp_seq=4 ttl=240 time=127 ms

    ----heise.de PING Statistics----
    5 packets transmitted, 5 packets received, 0.0% packet loss
    round-trip (ms) min/avg/max/med = 126/127/127/127

    ===========================================================================
    """

    #=============================================================================#
    import os, sys, socket, struct, select, time, signal

    if sys.platform == "win32":
    # On Windows, the best timer is time.clock()
    default_timer = time.clock
    else:
    # On most other platforms the best timer is time.time()
    default_timer = time.time

    #=============================================================================#
    # ICMP parameters

    ICMP_ECHOREPLY = 0 # Echo reply (per RFC792)
    ICMP_ECHO = 8 # Echo request (per RFC792)
    ICMP_MAX_RECV = 2048 # Max size of incoming buffer

    MAX_SLEEP = 1000

    class MyStats:
    thisIP = "0.0.0.0"
    pktsSent = 0
    pktsRcvd = 0
    minTime = 999999999
    maxTime = 0
    totTime = 0
    avrgTime = 0
    fracLoss = 1.0

    myStats = MyStats # NOT Used globally anymore.

    #=============================================================================#
    def checksum(source_string):
    """
    A port of the functionality of in_cksum() from ping.c
    Ideally this would act on the string as a series of 16-bit ints (host
    packed), but this works.
    Network data is big-endian, hosts are typically little-endian
    """
    countTo = (int(len(source_string)/2))*2
    sum = 0
    count = 0

    # Handle bytes in pairs (decoding as short ints)
    loByte = 0
    hiByte = 0
    while count < countTo:
    if (sys.byteorder == "little"):
    loByte = source_string[count]
    hiByte = source_string[count + 1]
    else:
    loByte = source_string[count + 1]
    hiByte = source_string[count]
    try: # For Python3
    sum = sum + (hiByte * 256 + loByte)
    except: # For Python2
    sum = sum + (ord(hiByte) * 256 + ord(loByte))
    count += 2

    # Handle last byte if applicable (odd-number of bytes)
    # Endianness should be irrelevant in this case
    if countTo > 16) + (sum & 0xffff) # Add high 16 bits to low 16 bits
    sum += (sum >> 16) # Add carry from above (if any)
    answer = ~sum & 0xffff # Invert and truncate to 16 bits
    answer = socket.htons(answer)

    return answer

    #=============================================================================#
    def do_one(myStats, destIP, hostname, timeout, mySeqNumber, numDataBytes, quiet = False):
    """
    Returns either the delay (in ms) or None on timeout.
    """
    delay = None

    try: # One could use UDP here, but it's obscure
    mySocket = socket.socket(socket.AF_INET, socket.SOCK_RAW, socket.getprotobyname("icmp"))
    except socket.error as e:
    print("failed. (socket error: '%s')" % e.args[1])
    raise # raise the original error

    my_ID = os.getpid() & 0xFFFF

    sentTime = send_one_ping(mySocket, destIP, my_ID, mySeqNumber, numDataBytes)
    if sentTime == None:
    mySocket.close()
    return delay

    myStats.pktsSent += 1

    recvTime, dataSize, iphSrcIP, icmpSeqNumber, iphTTL = receive_one_ping(mySocket, my_ID, timeout)

    mySocket.close()

    if recvTime:
    delay = (recvTime-sentTime)*1000
    if not quiet:
    print("%d bytes from %s: icmp_seq=%d ttl=%d time=%d ms" % (
    dataSize, socket.inet_ntoa(struct.pack("!I", iphSrcIP)), icmpSeqNumber, iphTTL, delay)
    )
    myStats.pktsRcvd += 1
    myStats.totTime += delay
    if myStats.minTime > delay:
    myStats.minTime = delay
    if myStats.maxTime destIP<.
    """
    #destIP = socket.gethostbyname(destIP)

    # Header is type (8), code (8), checksum (16), id (16), sequence (16)
    # (numDataBytes - 8) - Remove header size from packet size
    myChecksum = 0

    # Make a dummy heder with a 0 checksum.
    header = struct.pack(
    "!BBHHH", ICMP_ECHO, 0, myChecksum, myID, mySeqNumber
    )

    padBytes = []
    startVal = 0x42
    # 'cose of the string/byte changes in python 2/3 we have
    # to build the data differnely for different version
    # or it will make packets with unexpected size.
    if sys.version[:1] == '2':
    bytes = struct.calcsize("d")
    data = ((numDataBytes - 8) - bytes) * "Q"
    data = struct.pack("d", default_timer()) + data
    else:
    for i in range(startVal, startVal + (numDataBytes-8)):
    padBytes += [(i & 0xff)] # Keep chars in the 0-255 range
    #data = bytes(padBytes)
    data = bytearray(padBytes)

    # Calculate the checksum on the data and the dummy header.
    myChecksum = checksum(header + data) # Checksum is in network order

    # 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, 0, myChecksum, myID, mySeqNumber
    )

    packet = header + data

    sendTime = default_timer()

    try:
    mySocket.sendto(packet, (destIP, 1)) # Port number is irrelevant for ICMP
    except socket.error as e:
    print("General failure (%s)" % (e.args[1]))
    return

    return sendTime

    #=============================================================================#
    def receive_one_ping(mySocket, myID, timeout):
    """
    Receive the ping from the socket. Timeout = in ms
    """
    timeLeft = timeout/1000

    while True: # Loop while waiting for packet or timeout
    startedSelect = default_timer()
    whatReady = select.select([mySocket], [], [], timeLeft)
    howLongInSelect = (default_timer() - startedSelect)
    if whatReady[0] == []: # Timeout
    return None, 0, 0, 0, 0

    timeReceived = default_timer()

    recPacket, addr = mySocket.recvfrom(ICMP_MAX_RECV)

    ipHeader = recPacket[:20]
    iphVersion, iphTypeOfSvc, iphLength, \
    iphID, iphFlags, iphTTL, iphProtocol, \
    iphChecksum, iphSrcIP, iphDestIP = struct.unpack(
    "!BBHHHBBHII", ipHeader
    )

    icmpHeader = recPacket[20:28]
    icmpType, icmpCode, icmpChecksum, \
    icmpPacketID, icmpSeqNumber = struct.unpack(
    "!BBHHH", icmpHeader
    )

    if icmpPacketID == myID: # Our packet
    dataSize = len(recPacket) - 28
    #print (len(recPacket.encode()))
    return timeReceived, (dataSize+8), iphSrcIP, icmpSeqNumber, iphTTL

    timeLeft = timeLeft - howLongInSelect
    if timeLeft 0:
    myStats.fracLoss = (myStats.pktsSent - myStats.pktsRcvd)/myStats.pktsSent

    print("%d packets transmitted, %d packets received, %0.1f%% packet loss" % (
    myStats.pktsSent, myStats.pktsRcvd, 100.0 * myStats.fracLoss
    ))

    if myStats.pktsRcvd > 0:
    print("round-trip (ms) min/avg/max = %d/%0.1f/%d" % (
    myStats.minTime, myStats.totTime/myStats.pktsRcvd, myStats.maxTime
    ))

    print("")
    return

    #=============================================================================#
    def signal_handler(signum, frame):
    """
    Handle exit via signals
    """
    dump_stats()
    print("\n(Terminated with signal %d)\n" % (signum))
    sys.exit(0)

    #=============================================================================#
    def verbose_ping(hostname, timeout = 3000, count = 3,
    numDataBytes = 64, path_finder = False):
    """
    Send >countdestIPtimeout delay):
    time.sleep((MAX_SLEEP - delay)/1000)

    dump_stats(myStats)

    #=============================================================================#
    def quiet_ping(hostname, timeout = 3000, count = 3,
    numDataBytes = 64, path_finder = False):
    """
    Same as verbose_ping, but the results are returned as tuple
    """
    myStats = MyStats() # Reset the stats
    mySeqNumber = 0 # Starting value

    try:
    destIP = socket.gethostbyname(hostname)
    except socket.gaierror as e:
    return False

    myStats.thisIP = destIP

    # This will send packet that we dont care about 0.5 seconds before it starts
    # acrutally pinging. This is needed in big MAN/LAN networks where you sometimes
    # loose the first packet. (while the switches find the way... :/ )
    if path_finder:
    fakeStats = MyStats()
    do_one(fakeStats, destIP, hostname, timeout,
    mySeqNumber, numDataBytes, quiet=True)
    time.sleep(0.5)

    for i in range(count):
    delay = do_one(myStats, destIP, hostname, timeout,
    mySeqNumber, numDataBytes, quiet=True)

    if delay == None:
    delay = 0

    mySeqNumber += 1

    # Pause for the remainder of the MAX_SLEEP period (if applicable)
    if (MAX_SLEEP > delay):
    time.sleep((MAX_SLEEP - delay)/1000)

    if myStats.pktsSent > 0:
    myStats.fracLoss = (myStats.pktsSent - myStats.pktsRcvd)/myStats.pktsSent
    myStats.avrgTime = myStats.totTime / myStats.pktsRcvd

    # return tuple(max_rtt, min_rtt, avrg_rtt, percent_lost)
    return myStats.maxTime, myStats.minTime, myStats.avrgTime, myStats.fracLoss

    #=============================================================================#
    if __name__ == '__main__':

    # These should work:
    verbose_ping("8.8.8.8")
    verbose_ping("heise.de")
    verbose_ping("google.com")

    # Inconsistent on Windows w/ ActivePython (Python 3.2 resolves correctly
    # to the local host, but 2.7 tries to resolve to the local *gateway*)
    verbose_ping("localhost")

    # Should fail with 'getaddrinfo failed':
    verbose_ping("foobar_url.foobar")

    # Should fail (timeout), but it depends on the local network:
    verbose_ping("192.168.255.254")

    # Should fails with 'The requested address is not valid in its context':
    verbose_ping("0.0.0.0")

    Reply

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