Question

例如：
如何获得CIDR表示法10.66.114.0/24的更高IP地址在这种情况下，答案是：
10.66.114.1 - 10.66.114.254

Answer 1

这是它的要点（我是C家伙）：

unsigned int network = 0x0a427200; /* 10.66.114.0 */
unsigned int subnet_length = 24;

unsigned int mask = 0xfffffff << (32 - subnet_length);
unsigned int bcast = 0xffffffff >> (32 - subnet_length);

unsigned int start_ip = (network & mask) + 1;
unsigned int end_ip = (network & mask) + (bcast - 1);

Answer 2

#include <ncurses.h>
// ncurses.h includes stdio.h
#include <math.h>
#include <stdlib.h>

// determine network range of masked ip. eg: 192.168.113.0/25
// unsigned int network = 0x0a427200; /* 10.66.114.0 */
// unsigned int subnet_length = 24;
// 
// unsigned int mask = 0xfffffff << (32 - subnet_length);
// unsigned int bcast = 0xffffffff >> (32 - subnet_length);
// 
// unsigned int start_ip = (network & mask) + 1;
// unsigned int end_ip = (network & mask) + (bcast - 1);


int main(int argc, char *argv[])
{
//  char arg[50] = " ";
    char ipmask[50] = "192.168.113.0/25";
// determine network range of masked ip. eg: 192.168.113.0/25
    unsigned int network = 0xc0a87100; /* 192.168.113.0 */
    unsigned int subnet_length = 25;

    unsigned int mask = 0xfffffff << (32 - subnet_length);
    unsigned int bcast = 0xffffffff >> (subnet_length);
//   unsigned int bcast = 0xffffffff >> (32 - subnet_length);

    unsigned int start_ip = (network & mask) + 1;
    unsigned int end_ip = (network & mask) + (bcast);

    initscr();
    cbreak();
    printw("\nipmask %s\nstart %x end %x range %x\n"
      "press any key\n", ipmask, start_ip, end_ip, end_ip - start_ip + 1);

    getch();
    endwin(); // close ncurses library and restores previous console
    return(0);

}
/*****************************************************************************/
// end netmask

    gcc -Wall netmask.c -o netmask -lm -lncurses

如何使用Java从CIDR表示法或地址网络掩码对中获取ip范围

2 个答案: