黑客编程教程（十四）单线程TCP端口扫描器

第十四节 单线程TCP端口扫描器#include<winsock2.h>#include<stdio.h>#include <time.h>                          //计时需要用到的头文件#pragma comment(lib,"ws2_32.lib")#include <time.h>//计时需要用到的头文件clock_t start,end;//程序运行的起始和结束时间float costtime;//程序耗时void usage(void){printf("\tusage: tcpscan RemoteIP StartPort-EndPort\n");printf("\tExample: tcpscan 192.168.1.1 80-100\n");}int main(int argc,char **argv){char *host;int startport,endport;    char *p;if(argc!=3){usage();return 0;}p=argv[2];//处理端口参数    if(strstr(argv[2],"-"))    {    startport=atoi(argv[2]);        for(;*p;)            if(*(p++)=='-')break;        endport=atoi(p);                if(startport<1 || endport>65535)        {    printf("Port Error!\n");            return 0;        }    }host=argv[1];    WSADATA ws;SOCKET s;struct sockaddr_in addr;int result;long lresult;lresult=WSAStartup(MAKEWORD(1,1), &ws);addr.sin_family =AF_INET;addr.sin_addr.s_addr =inet_addr(host);    start=clock();//开始计时for (int i=startport;i<endport;i++){s=socket(AF_INET, SOCK_STREAM, 0);        addr.sin_port = htons(i);if(s==INVALID_SOCKET)break;result=connect(s, (struct sockaddr*)&addr,sizeof(addr)); if(result==0){printf("%s %d\n",host,i);closesocket(s);}}end=clock();//计时结束costtime= (float)(end - start) / CLOCKS_PER_SEC;  //转换时间格式printf("Cost time:%f second",costtime);//显示耗时WSACleanup();}