python剑指网络篇一

#coding:utf-8
__author__ = ‘similarface‘
#!/usr/bin/env python

import socket
#二进制和ASCII互转及其它进制转换
from binascii import hexlify
def get_remote_machine_info(remote_host):
    ‘‘‘
    获取根据域名获取IP地址
    :param remote_host: 域名
    :return:IP地址
    ‘‘‘
    try:
        #SimilarFacedeMacBook-Pro:~ similarface$ ping www.python.org
        #PING python.map.fastly.net (103.245.222.223): 56 data bytes
        print("%s的IP地址:%s" %(remote_host,socket.gethostbyname(remote_host)))
    except socket.error,err_msg:
        print("%s: %s" %(remote_host,err_msg))


def convert_ip4_address():
    ‘‘‘
    转化IP地址
    ‘‘‘
    for ip_addr in [‘127.0.0.1‘,‘192.168.0.1‘]:
        #IP地址转换为一个32位的网络序列IP地址。
        packed_ip_addr=socket.inet_aton(ip_addr)
        #将一个十进制网络字节序转换为点分十进制IP格式的字符串。
        unpacked_ip_addr=socket.inet_ntoa(packed_ip_addr)
        print "IP地址: %s => 打包: %s, 非打包: %s" %(ip_addr, hexlify(packed_ip_addr), unpacked_ip_addr)


def find_service_name():
    ‘‘‘
    根据端口获取服务的名称
    :return:
    ‘‘‘
    protocolname=‘tcp‘
    for port in range(53,22,80):
        try:
            print "Port: %s => service name: %s" %(port, socket.getservbyport(port, protocolname))
        except Exception,e:
            print(e)

    print "Port: %s => service name: %s" %(53, socket.getservbyport(53, ‘udp‘))


def convert_integer():
    ‘‘‘
    #ntohl()是将一个无符号长整形数从网络字节顺序转换为主机字节顺序。
    #将主机数转换成无符号长整型的网络字节顺序。本函数将一个32位数从主机字节顺序转换成网络字节顺序。
    :return:
    ‘‘‘
    data=1234
    print "原数据: %s => 长主机字节顺序: %s, 长网络字节顺序: %s"%(data, socket.ntohl(data), socket.htonl(data))
    print "原数据: %s => 短主机字节顺序: %s, 短网络字节顺序: %s"%(data, socket.ntohs(data), socket.htons(data))



def test_socket_timeout():
    s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    print "默认的超时时间: %s" %s.gettimeout()
    s.settimeout(100)
    print "当前的超时时间: %s" %s.gettimeout()

import sys,socket,argparse
def main():
    parser=argparse.ArgumentParser(description="Socket 异常处理")
    parser.add_argument(‘--host‘,action=‘store‘,dest=‘host‘,required=False)
    parser.add_argument(‘--port‘,action="store",desc=‘port‘,type=int,required=False)
    parser.add_argument(‘--file‘,action-"store",desc=‘file‘,required=False)
    given_args=parser.parse_args()
    host=given_args.host
    port=given_args.port
    filename=given_args.file

    try:
        s=socket.socket(socket.AF_INET,socket.SOCK_STREAM)
    except socket.error,e:
        print("Error creating socket: %s" % e )
        sys.exit(1)

    try:
        s.connect((host,port))
    except socket.gaierror,e:
        print "Address-related error connecting to server: %s" % e
        sys.exit(1)
    except socket.error,e:
        print "Connection error: %s" % e
        sys.exit(1)

    try:
        s.sendall("GET %s HTTP/1.0\r\n\r\n" % filename)
    except socket.error, e:
        print "Error sending data: %s" % e
        sys.exit(1)

    while 1:
        try:
            buf = s.recv(2048)
        except socket.error, e:
            print "Error receiving data: %s" % e
            sys.exit(1)
        if not len(buf):
            break
           # write the received data
        sys.stdout.write(buf)

if __name__ == "__main__":
    remote_host=‘www.python.org‘
    get_remote_machine_info(remote_host)
    convert_ip4_address()
    print(‘------find_service_name------‘)
    find_service_name()
    print(‘------convert_integer------‘)
    convert_integer()
    print(‘------main------‘)
    main()