
平台论坛博客文库

› 论坛 › 程序设计 › C/C++ › 端口扫描程序的俩问题，望高手指点

端口扫描程序的俩问题，望高手指点 [复制链接]

hawfeng

白手起家

论坛徽章:: 0

电梯直达

1楼 [收藏(0)] [报告]

发表于 2005-08-13 12:29 |只看该作者 |倒序浏览

以下是自己以前写的一个端口扫描程序，但是
1。扫描结果很不稳定有的时候同一IP每次扫描出来的结果都不一样（以前问过，但是没有解决）
2。如果目的主机没有防火墙，很有可能显示对方开放所有端口。
另外，如何通过扫描区别网关？

#include <stdio.h>;
#include <sys/time.h>;
#include <sys/socket.h>;
#include <sys/types.h>;
#include <netinet/in.h>;
#include <unistd.h>;
#include <fcntl.h>;
#include <netdb.h>;
#include <string.h>;
#ifndef MAXNAMELEN
#define MAXNAMELEN 256
#endif
#define MAXPORT 256
u_long startip,endip;
int port[MAXPORT]={21,23,25,53,79,80,88,109,110,135,139,1080,1434,3389,7626,8080};
int portcount=16;
struct timeval time={5,0};
fd_set fdset;
void usage();
void setiphost();
void resetport(char* newport);
void setip(char* start,char* end);
void scan(u_long ip);
main(int argc,char *argv[])
{
int i=1;
u_long ip;
printf("%u\n",argc);
printf("%u\n",inet_addr(argv[1]));
switch(argc)
{
case 1:
setiphost();
break;
case 2:
printf("argc:2\n");
if(argv[1]=="h")
{
usage();
}
else if(strchr(argv[1],',')!=0)
{
setip(argv[1],argv[1]);
}
else
{
resetport(argv[1]);
}
break;
case 3:
printf("argc:3\n");
setip(argv[1],argv[2]);
break;
case 4:
printf("argc:4\n");
setip(argv[1],argv[2]);
resetport(argv[3]);
break;
default:
usage();
}
printf("we are going to scan %u\t%u\n",startip,endip);
printf("%s\t%s\n",argv[1],argv[2]);
for(ip=startip;ip<=endip;ip++)
{
scan(ip);
printf("\n");
}
}
void usage()
{
printf("scan startip endip port\n");
printf("for example:scan 11.11.11.11 11.11.11.60 21,23,80\n");
printf("if there is no port,the program will scan port21,23,25,53,79,80,88,109,110,135,139,1080,1434,3389,7626,8080.\n");
printf("if there is no startip and endip,the program will scan the host.\n");
exit(0);
return;
}
void setip(char* start,char* end)
{
u_long change;
startip=ntohl(inet_addr(start));
printf("start\t%s\t%u\n",start,startip);
endip=ntohl(inet_addr(end));
printf("%d\n",inet_addr(end));
printf("end\t%s\t%u\n",end,endip);
if(startip>;endip)
{
change=startip;
startip=endip;
endip=change;
}
return;
}
void setiphost()
{
struct hostent *hst;
char name[MAXNAMELEN];
size_t size;
if(gethostname(name,size)!=0)
{
printf("gethostname() failed.\n");
exit(-1);
}
if(hst=gethostbyname(name))
{
printf("local ip address:%s",hst->;h_addr_list[0]);
setip(hst->;h_addr_list[0],hst->;h_addr_list[0]);
}
else
{
printf("gethostbyname() failed.\n");
usage();
}
return;
}
void resetport(char* newport)
{
char *p;
char *douhao=",";
portcount=0;
if(p=strtok(newport,douhao))
{
port[0]=atoi(p);
printf("you are going to scan port:%d\t",port[0]);
portcount=1;
}
else
{
printf("resetport() failed.\n");
usage();
}
while(p=strtok(NULL,douhao))
{
port[portcount]=atoi(p);
printf("%d\t",port[portcount]);
portcount++;
}
}
void scan(u_long ip)
{
struct sockaddr_in sckddr;
int skt,i,j,m;
int sasize=sizeof(sckddr);
sckddr.sin_family=AF_INET;
sckddr.sin_addr.s_addr=htonl(ip);
for(i=0;i<portcount;i++)
{
sckddr.sin_port=htons(port[i]);
if((skt=socket(AF_INET,SOCK_STREAM,0))<0)
{
printf("socket() failed.\n");
exit(-1);
}
if(fcntl(skt,F_SETFL,O_NDELAY)<0)
{
printf("fcntl() failed.\n");
exit(-1);
}
connect(skt,(struct sockaddr *)&sckddr,sasize);
FD_ZERO(&fdset);
FD_SET(skt,&fdset);
j=select(skt+1,(fd_set *)0,&fdset,(fd_set *)0,&time);
switch (j)
{
case -1:
printf("select() failed.\n");
exit(-1);
case 0:
close(skt);
break;
default:
if(FD_ISSET(skt,&fdset))
{
printf("%s\topen\t%u\n",inet_ntoa(ntohl(ip)),port[i]);
}
}
}
}