linux 端口扫描_linux上端口扫描

100分求linux下C语言端口扫描代码

linux tcp udp 端口扫描源程序

#include sys/socket.h

#include netinet/in.h

#include arpa/inet.h

#include unistd.h

#include errno.h

#include netdb.h

#include stdio.h

#include string.h

#include netinet/ip_icmp.h

#include stdlib.h

#include signal.h

#include libxml/parser.h

#include libxml/tree.h

#define TRUE 1

#define FALSE 0

#define UDP "UDP"

#define TCP "TCP"

#define tcp "tcp"

#define udp "udp"

typedef struct _GsSockStru{

int fd;

int len;

struct sockaddr_in addr;

}GsSockStru;

static int tcptest( char ip[32], char port[20]);

static int udptest( char ip[32], char port[20]);

void sig_alrm( int signo );

static GsSockStru test_sock;

int

main( int argc, char** argv)

{

char string[64];

char port[20];

char pro[20];

char ip[32];

int res;

int i = 0;

int k = 0;

if( argc2 || argc2 )

{

printf("鍙傛暟涓嶆纭?-1\n");

return ( -1 );

}

strcpy( string, argv[1]);

while( *string )

{

if( string[i] == ':' )

break;

pro[k] = string[i];

k++;

i++;

}

pro[k] = '\0';

i++;

k = 0;

while( *string )

{

if( string[i] == ':')

break;

ip[k] = string[i];

k++;

i++;

}

ip[k] = '\0';

i++;

k=0;

while( *string )

{

if( string[i] == '\0')

break;

port[k] = string[i];

k++;

i++;

}

port[k] = '\0';

i++;

memset( test_sock, 0, sizeof( test_sock ) );

if ( ( strcmp( TCP, pro) != 0 ) ( strcmp( UDP, pro) != 0 ) ( strcmp( tcp, pro) != 0 ) ( strcmp( udp, pro) != 0 ))

{

printf ( "鍙傛暟涓嶆纭?锛?\n" );

return (-1);

}

if ( strcmp( TCP, pro) == 0 || strcmp( tcp, pro) == 0 )

res = tcptest( ip, port );

if ( strcmp( UDP, pro) == 0 || strcmp( udp, pro) == 0 )

res = udptest( ip, port );printf("%d\n",res);

return ( res );

}

int

tcptest( char ip[32], char port[20])

{

int res;

struct timeval tv;

test_sock.fd = socket( AF_INET, SOCK_STREAM, 0 );

if ( test_sock.fd 0 )

{

printf( "create socket failed -3 \n" );

return ( -3 );

}

memset( ( test_sock.addr ), 0, sizeof( test_sock.addr ) );

test_sock.addr.sin_family = AF_INET;

test_sock.addr.sin_port = htons( atoi( port ) );

inet_pton( AF_INET, ip, test_sock.addr.sin_addr );

test_sock.len = sizeof( struct sockaddr );

tv.tv_sec = 10;

tv.tv_usec = 0;

setsockopt( test_sock.fd, SOL_SOCKET, SO_RCVTIMEO,

(const char *)tv, sizeof( tv ) );

res = connect( test_sock.fd,

( struct sockaddr * )( ( test_sock.addr ) ),

test_sock.len );

if ( res 0 )

{

fprintf( stderr, "connect failed 0\n" );

close( test_sock.fd );

return FALSE;

}

close( test_sock.fd );

return TRUE;

}

int udptest( char ip[32], char port[20])

{

struct icmphdr *icmp_header;

struct sockaddr_in target_info;

int target_info_len;

fd_set read_fd;

int scan_port;

char recvbuf[5000];

struct sockaddr_in target_addr;

int icmp_socket;

int udp_socket;

struct timeval tv;

icmp_header = (struct icmphdr *)(recvbuf+sizeof(struct iphdr));

scan_port = atoi( port );

target_addr.sin_family = AF_INET;

inet_pton( AF_INET, ip, target_addr.sin_addr );

target_addr.sin_port = htons(scan_port);

if ((udp_socket=socket(AF_INET,SOCK_DGRAM,0))==-1)

{

printf("create socket failed -3\n");

return -3;

}

if ((icmp_socket=socket(AF_INET,SOCK_RAW,IPPROTO_ICMP))==-1)

{

printf("Create raw socket failed -3\n");

return -3;

}

sendto(udp_socket,NULL,0,0,(void *)target_addr,sizeof(target_addr));

FD_ZERO(read_fd);

FD_SET(icmp_socket,read_fd);

tv.tv_sec = 1;

tv.tv_usec = 0;

select(FD_SETSIZE,read_fd,NULL,NULL,tv);

for (;;){

if (FD_ISSET(icmp_socket,read_fd))

{

target_info_len = sizeof(target_info);

recvfrom(icmp_socket,recvbuf,5000,0,

(struct sockaddr *)target_info,target_info_len);

if (target_info.sin_addr.s_addr == target_addr.sin_addr.s_addr

icmp_header-type == 3 icmp_header-code=12)

{

printf("Port %d : Close\n",scan_port);

return (0);

}

}

return (1) ;

}

}

安装的Linux使用nmap扫描端口时显示没有指定目标，所以扫描了0台主机，这应该怎么办

你使用的什么指令？？？

首先你得知道自己的网段IP，输入：ifconfig

找到自己的网段，一般是192.168.1.***

这个不一定的，Nmap扫描的话方式比较多，给你一个教程网站参考一下，不过是英文的。如果有困难的话我自己有一份报告，可提供参考。但是还是希望你尽量参考这个网站的，详细许多。

linux下已经更改了ssh默认登陆端口22，如何扫描出来更改后的端口号呢。使用NMAP扫描不到，有其他方法么？

你可以在这个文件中找到你设置的端口号 /etc/ssh/sshd_config,这里面”Port“字段后面的数字序列就是更改后的端口号了

linux下用C写的一个端口扫描器,想得到扫描主机的操作系统类型

nmap 命令行

zenmap 图形化界面

一般能扫描出主机的操作系统版本