Question

我正在尝试运行此ICMP pinger应用程序（Python 2.7）。它给了我这个错误信息。

追踪（最近一次通话）：第125行平（＆＃34; www.poly.edu＆＃34）第120行，在ping delay = doOnePing（dest，timeout）第104行，在doOnePing中提升socket.error（msg）错误：不允许操作

我不确定是什么问题。代码有问题吗？或者代码是否正确并且其他原因不允许使用该功能？

from socket import *
import os
import sys
import struct
import time
import select
import binascii
import socket

ICMP_ECHO_REQUEST = 8
timeRTT = []
packageSent =0;
packageRev = 0;

def checksum(str):
    csum = 0
    countTo = (len(str) / 2) * 2
    count = 0
    while count < countTo:
        thisVal = ord(str[count+1]) * 256 + ord(str[count])
        csum = csum + thisVal
        csum = csum & 0xffffffffL
        count = count + 2
    if countTo < len(str):
        csum = csum + ord(str[len(str) - 1])
        csum = csum & 0xffffffffL
    csum = (csum >> 16) + (csum & 0xffff)
    csum = csum + (csum >> 16)
    answer = ~csum
    answer = answer & 0xffff
    answer = answer >> 8 | (answer << 8 & 0xff00)
    return answer

def receiveOnePing(mySocket, ID, timeout, destAddr):
    global packageRev,timeRTT
    timeLeft = timeout
    while 1:
        startedSelect = time.time()
        whatReady = select.select([mySocket], [], [], timeLeft)
        howLongInSelect = (time.time() - startedSelect)
        if whatReady[0] == []: # Timeout
            return "0: Destination Network Unreachable,"
        timeReceived = time.time()
        recPacket, addr = mySocket.recvfrom(1024)

    #Fill in start
        #Fetch the ICMP header from the IP packet
        icmpHeader = recPacket[20:28]
        requestType, code, revChecksum, revId, revSequence = struct.unpack('bbHHh',icmpHeader)
        if ID == revId:
            bytesInDouble = struct.calcsize('d')
            #struct.calcsize(fmt) Return the size of the struct (and hence of the string) corresponding to the given format.
        #struct.unpack(fmt, buffer[, offset=0]) Unpack the buffer according to the given format. The result is a tuple even if it contains exactly one item. The buffer must contain at least the amount of data required by the format (len(buffer[offset:]) must be at least calcsize(fmt)).
            timeData = struct.unpack('d',recPacket[28:28 + bytesInDouble])[0] 
            timeRTT.append(timeReceived - timeData)
            packageRev += 1
            return timeReceived - timeData
        else:
            return "ID does not match"
        #Fill in end

        timeLeft = timeLeft - howLongInSelect
        if timeLeft <= 0:
            return "1: Request timed out."

def sendOnePing(mySocket, destAddr, ID):
    global packageSent
    # Header is type (8), code (8), checksum (16), id (16), sequence (16)

    myChecksum = 0
    # Make a dummy header with a 0 checksum.
    # struct -- Interpret strings as packed binary data
    header = struct.pack("bbHHh", ICMP_ECHO_REQUEST, 0, myChecksum, ID, 1)
    data = struct.pack("d", time.time())
    # Calculate the checksum on the data and the dummy header.
    myChecksum = checksum(header + data)

    # Get the right checksum, and put in the header
    if sys.platform == 'darwin':
        myChecksum = socket.htons(myChecksum) & 0xffff
        #Convert 16-bit integers from host to network byte order.
    else:
        myChecksum = socket.htons(myChecksum)

    header = struct.pack("bbHHh", ICMP_ECHO_REQUEST, 0, myChecksum, ID, 1)
    packet = header + data

    mySocket.sendto(packet, (destAddr, 1))
    packageSent += 1
    # AF_INET address must be tuple, not str
    #Both LISTS and TUPLES consist of a number of objects
    #which can be referenced by their position number within the object

def doOnePing(destAddr, timeout):
    icmp = socket.getprotobyname("icmp")
    #SOCK_RAW is a powerful socket type. For more details see:http://sock-raw.org/papers/sock_raw

    #Fill in start
    #Create Socket here
    try:
        mySocket = socket.socket(socket.AF_INET, socket.SOCK_RAW, icmp)
    except socket.error, (errno, msg):
        if errno == 1:
            raise socket.error(msg)
    #Fill in end

    myID = os.getpid() & 0xFFFF  #Return the current process i
    sendOnePing(mySocket, destAddr, myID)
    delay = receiveOnePing(mySocket, myID, timeout, destAddr)
    mySocket.close()
    return delay

def ping(host, timeout=1):
    #timeout=1 means: If one second goes by without a reply from the server,
    dest = socket.gethostbyname(host)
    print "Pinging " + dest + " using Python:"
    print ""
    #Send ping requests to a server separated by approximately one second
    while 1 :
        delay = doOnePing(dest, timeout)
        print "RTT:",delay
        time.sleep(1)# one second
    return delay

ping("www.poly.edu")

Answer 1

要使用raw_sockets，Python需要以root身份运行。如果你通过sudo运行脚本（假设Linux / UNIX），它应该工作。如果使用Windows，请以管理员身份运行Python。

值得一提的是，当我在CentOS 6.5虚拟机上以root身份运行时，你的代码对我来说很合适。

Python中的ICMP pinger应用程序 - 错误：不允许操作？

1 个答案: