udp端口扫描程序代码

// udp.cpp : 定义控制台应用程序的入口点。

//

#include "stdafx.h"

#include

#include

#pragma comment(lib, "ws2_32.lib")

#define MAXBUFF 8192

#define ICMP_UNREACH_PORT 3

#define ICMP_UNREACH 4

enum {CMD_NAME, DST_IP

, START_PORT, LAST_PORT};

structip{

unsigned int ip_v:4; // 版本

unsigned int ip_hl:4; // 头部长

unsigned char ip_tos; // 服务类型

unsigned short ip_len; // 总长

unsigned short ip_id; //鉴定域

unsigned short ip_flags; //IP标志

unsigned short ip_off; // 片偏移

unsigned char ip_ttl; // TTL

unsigned char ip_protocol; // 协议

unsigned short ip_sum; // 头部效验和

structin_addrip_src, ip_dest; //源ip和目的IP

#define IP_RF 0x8000 // 标记收到数据

#define IP_DF 0x4000

#define IP_MF 0x2000

#define IP_OFFMASK 0x1fff

};

structicmp{

unsigned short inticmp_type;

unsigned short inticmp_code;

unsigned long inticmp_cksum;

unsigned long inticmp_id;

unsigned long inticmp_seq;

unsigned short inticmp_data[1];

};

int main(intargc, char *argv[]) {

structtimevaltv;

fd_setselect_fd;

char buff[MAXBUFF];

intdstport, startport, endport;

if (argc != 4) {

fprintf(stdout, " usage: %s 目的ip起始端口目的端口\n", argv[CMD_NAME]); exit(EXIT_FAILURE);

}

WSADatawsaData;

WSAStartup(MAKEWORD(2,2), &wsaData);

structsockaddr_insend_sa;

// 发送端地址信息

memset(&send_sa, 0, sizeof(send_sa));

send_sa.sin_family = AF_INET;

send_sa.sin_addr.s_addr = inet_addr(argv[DST_IP]);

startport = atoi(argv[START_PORT]);

endport = atoi(argv[LAST_PORT]);

SOCKET sock_send = socket(AF_INET, SOCK_DGRAM, 0);

// 发送用的描述符

if (sock_send< 0) {

perror(" sock(SOCK_DGRAM)");

closesocket(sock_send);

exit(EXIT_FAILURE);

}

SOCKET sock_recv = socket(AF_INET, SOCK_RAW, IPPROTO_ICMP); // 接收用的描述符if (sock_recv< 0) {

perror(" socket(SOCK_RAW)");

closesocket(sock_recv);

exit(EXIT_FAILURE);

}

for (dstport = startport; dstport<= endport; dstport ++) {

printf("扫描端口%d\r", dstport);

fflush(stdout);

send_sa.sin_port = htons(dstport);

int res = sendto(sock_send, NULL, 0, 0, (structsockaddr *) &send_sa, sizeof(send_sa));

https://www.360docs.net/doc/cc3435261.html,_sec = 1;

https://www.360docs.net/doc/cc3435261.html,_usec = 0;

while (1) {

FD_ZERO(&select_fd);

FD_SET(sock_recv, &select_fd);

if (select(sock_recv + 1, &select_fd, NULL, NULL, &tv) > 0) {

structip *ip;

structicmp *icmp;

inthlen;

int port;

memset(&ip, 0, sizeof(ip));

if (recvfrom(sock_recv, buff, MAXBUFF, 0, NULL, NULL) != 56)

continue;

ip = (structip *)buff;

hlen = ip->ip_hl<<2;

icmp = (structicmp *)(buff+hlen);

port = ntohs(*(u_short *)(buff+20+8+20+2));

if

((ip->ip_src.s_addr

!=

send_sa.sin_addr.s_addr)

||

(icmp->icmp_type

!=

ICMP_UNREACH)

||

(icmp->icmp_code != ICMP_UNREACH_PORT) || (port != dstport)) continue;

}

else {

structservent *se;

se = getservbyport(htons(dstport), "udp");

if (se != NULL)

printf("%5d %-20s\n", dstport, (se == NULL) ? "unknown": se->s_name); }

break;

}

}

closesocket(sock_send);

closesocket(sock_recv);

int WSACleanup();

return(0);

}