IpToCidr函数

1楼 2楼的兄弟说完我以为我手误结果自己又测试了下确实ip2cidr("36.96.0.0","36.223.255.255") 执行结果36.96.0.0/9
而36.96.0.0/9 生成IP的区间为 36.0.0.1 -36.127.255.254

那可能我之前表述错误了我的需求就是用函数实现首IP地址和尾IP地址的区间转化为CIDR格式这样就可以用来查询某个IP地址是否属于这个CIDR区域，其中检验的方法就是用CIDR再反生成首IP地址和尾IP地址的区间。
函数功能类似于http://ip2cidr.com 上的

其实这是 ip2cidr 的 bug
函数的原型来自 php 手册，只是增加了分段的功能
可以看到，分段是在原函数发现做为一段不行的时候进行的
但由于先天不足，他并没有把你的传入不能作为一段判别出来

不知道这个网站http://ip2cidr.com/ 它是怎么实现的网上的资源好少

一篇国外的文章用JAVA实现了
import java.util.ArrayList;
import java.util.List;
import java.util.regex.Matcher;
import java.util.regex.Pattern;public class RangeToCidr {
    private static final String IP_ADDRESS = "(\\d{1,3})\\.(\\d{1,3})\\.(\\d{1,3})\\.(\\d{1,3})";
    private static final Pattern addressPattern = Pattern.compile(IP_ADDRESS);    public static List<String> rangeToCidrList(String istart, String iend)  {
        int start = toInteger(istart);
        int end = toInteger(iend);        List<String> result = new ArrayList<String>();        while (end >= start) {
            int maxsize = imaxblock( start, 32);
            double x = (Math.log(end - start + 1) / Math.log(2) ) ;
            int maxdiff = (int) (Math.floor(32 - Math.floor(x)));            String ip = intToIP(start);
            if (maxsize < maxdiff) {
                maxsize = maxdiff;
            }
            result.add( ip + "/" + (int)maxsize );
            start += Math.pow(2, (32-maxsize));
        }
        return result;
    }    private static int toInteger(String address) {
        Matcher matcher = addressPattern.matcher(address);
        if (matcher.matches()) {
            return matchAddress(matcher);
        }
        else
            throw new IllegalArgumentException("Could not parse [" + address + "]");
    }    private static int matchAddress(Matcher matcher) {
        int addr = 0;
        for (int i = 1; i <= 4; ++i) {
            int n = (rangeCheck(Integer.parseInt(matcher.group(i)), -1, 255));
            addr |= ((n & 0xff) << 8*(4-i));
        }
        return addr;
    }    private static int rangeCheck(int value, int begin, int end) {
        if (value > begin && value <= end) // (begin,end]
            return value;        throw new IllegalArgumentException("Value [" + value + "] not in range ("+begin+","+end+"]");
    }    private static String intToIP(int val) {
        int octets[] = new int[4];
        for (int j = 3; j >= 0; --j)
            octets[j] |= ((val >>> 8*(3-j)) & (0xff));        StringBuilder str = new StringBuilder();
        for (int i =0; i < octets.length; ++i){
            str.append(octets[i]);
            if (i != octets.length - 1) {
                str.append(".");
            }
        }
        return str.toString();
    }    private static long imask(int t)    {
        return (long)(Math.pow(2, 32) - Math.pow(2, 32-t) ) ;
    }    private static int imaxblock(long ibase, int tbit)  {
        while (tbit > 0)    {
            long im = imask(tbit-1);
            long imand = ibase & im ;
            if (imand != ibase) {
                break;
            }
            tbit--;
        }
        return tbit;
    }
}

$r = ip2cidr("36.96.0.1","36.223.255.255");
print_r($r);function ip2cidr($ip_start,$ip_end) {
  $res = array();
  if(long2ip(ip2long($ip_start))!=$ip_start or long2ip(ip2long($ip_end))!=$ip_end)
    return !trigger_error('ip 不合法', E_USER_NOTICE);
  $ipl_start = ip2long($ip_start);
  if($ipl_start < 0) $ipl_start += 0x100000000;  $ipl_end = ip2long($ip_end);
  if($ipl_end<0) $ipl_end += 0x100000000;  $ipl=$ipl_start;
  do {
    $k = strrpos(sprintf('%032b', $ipl), '1');
    $cidr = $k + 1;
    $dk = pow(2, 32-$k-1);
    $mask = $dk - 1;
    $res[] = sprintf("%s/%d", long2ip($ipl & ~$mask), $cidr);
    $ipl += $dk;
  }while($ipl < $ipl_end);
  return $res;
} Array
(
    [0] => 36.96.0.1/32
    [1] => 36.96.0.2/31
    [2] => 36.96.0.4/30
    [3] => 36.96.0.8/29
    [4] => 36.96.0.16/28
    [5] => 36.96.0.32/27
    [6] => 36.96.0.64/26
    [7] => 36.96.0.128/25
    [8] => 36.96.1.0/24
    [9] => 36.96.2.0/23
    [10] => 36.96.4.0/22
    [11] => 36.96.8.0/21
    [12] => 36.96.16.0/20
    [13] => 36.96.32.0/19
    [14] => 36.96.64.0/18
    [15] => 36.96.128.0/17
    [16] => 36.97.0.0/16
    [17] => 36.98.0.0/15
    [18] => 36.100.0.0/14
    [19] => 36.104.0.0/13
    [20] => 36.112.0.0/12
    [21] => 36.128.0.0/9
)

还有个更简单的其中2个函数PHP都有库函数  实测也可以
import java.util.ArrayList;
import java.util.List;public class RangeToCidr {
    public static List<String> range2cidrlist( String startIp, String endIp ) {
        long start = ipToLong(startIp);
        long end = ipToLong(endIp);                   ArrayList<String> pairs = new ArrayList<String>();
        while ( end >= start ) {
            byte maxsize = 32;
            while ( maxsize > 0) {
                long mask = CIDR2MASK[ maxsize -1 ];
                long maskedBase = start & mask;                                 if ( maskedBase != start ) {
                    break;
                }                                 maxsize--;
            }
            double x = Math.log( end - start + 1) / Math.log( 2 );
            byte maxdiff = (byte)( 32 - Math.floor( x ) );
            if ( maxsize < maxdiff) {
                maxsize = maxdiff;
            }
            String ip = longToIP(start);
            pairs.add( ip + "/" + maxsize);
            start += Math.pow( 2, (32 - maxsize) );
        }
        return pairs;
    }           public static final int[] CIDR2MASK = new int[] { 0x00000000, 0x80000000,
        0xC0000000, 0xE0000000, 0xF0000000, 0xF8000000, 0xFC000000,
        0xFE000000, 0xFF000000, 0xFF800000, 0xFFC00000, 0xFFE00000,
        0xFFF00000, 0xFFF80000, 0xFFFC0000, 0xFFFE0000, 0xFFFF0000,
        0xFFFF8000, 0xFFFFC000, 0xFFFFE000, 0xFFFFF000, 0xFFFFF800,
        0xFFFFFC00, 0xFFFFFE00, 0xFFFFFF00, 0xFFFFFF80, 0xFFFFFFC0,
        0xFFFFFFE0, 0xFFFFFFF0, 0xFFFFFFF8, 0xFFFFFFFC, 0xFFFFFFFE,
        0xFFFFFFFF };           private static long ipToLong(String strIP) {
        long[] ip = new long[4];
        String[] ipSec = strIP.split("\\.");
        for (int k = 0; k < 4; k++) {
            ip[k] = Long.valueOf(ipSec[k]);
        }                 return (ip[0] << 24) + (ip[1] << 16) + (ip[2] << 8) + ip[3];
    }           private static String longToIP(long longIP) {
        StringBuffer sb = new StringBuffer("");
        sb.append(String.valueOf(longIP >>> 24));
        sb.append(".");
        sb.append(String.valueOf((longIP & 0x00FFFFFF) >>> 16));
        sb.append(".");
        sb.append(String.valueOf((longIP & 0x0000FFFF) >>> 8));
        sb.append(".");
        sb.append(String.valueOf(longIP & 0x000000FF));           return sb.toString();
    }
}

版主大大看12楼的 JAVA 函数思路是否可以优化您的代码以生成3个CIDR 36.96.0.0/11 36.128.0.0/10 36.192.0.0/11
最终让这个函数在PHP沉淀下来为大家造福

$r = ip2cidr("36.96.0.0","36.223.255.255");
print_r($r);
Array
(
[0] => 36.96.0.0/11
[1] => 36.128.0.0/9
)
你给的那个链接，最后一节的结果是错的

您说的是http://ip2cidr.com/ 还是12楼的函数？

$r = ip2cidr("36.96.0.0","36.223.255.255");
print_r($r);function ip2cidr($ip_start,$ip_end) {
  $res = array();
  if(long2ip(ip2long($ip_start))!=$ip_start or long2ip(ip2long($ip_end))!=$ip_end)
    return !trigger_error('ip 不合法', E_USER_NOTICE);
  $ipl_start = ip2long($ip_start);
  if($ipl_start < 0) $ipl_start += 0x100000000;  $ipl_end = ip2long($ip_end);
  if($ipl_end<0) $ipl_end += 0x100000000;  $ipl=$ipl_start;
  do {
    $k = strrpos(sprintf('%032b', $ipl), '1');
    $cidr = $k + 1;
    $dk = pow(2, 32-$k-1);
    if($ipl + $dk > $ipl_end) { $dk /= 2; $cidr++; }
    $mask = $dk - 1;
    $res[] = sprintf("%s/%d", long2ip($ipl & ~$mask), $cidr);
    $ipl += $dk;
  }while($ipl < $ipl_end);
  return $res;
} Array
(
    [0] => 36.96.0.0/11
    [1] => 36.128.0.0/10
    [2] => 36.192.0.0/11
)

拆的好开呀版主大大看看还能优化下吗
$ip_st = "103.233.183.0";
$ip_end = "103.233.183.255";
print $ip_st."-".$ip_end."<br>";
$cidr_arr = ip2cidr($ip_st,$ip_end );print_r($cidr_arr);
print "<br>";
for($i = 0 ; $i < count($cidr_arr); $i++)
{
print $cidr_arr[$i]." : ";
print cidr_conv($cidr_arr[$i])."<br>";
}103.233.183.0-103.233.183.255
Array ( [0] => 103.233.183.0/25 [1] => 103.233.183.128/26 [2] => 103.233.183.192/27 [3] => 103.233.183.224/28 [4] => 103.233.183.240/29 [5] => 103.233.183.248/30 [6] => 103.233.183.252/31 [7] => 103.233.183.254/32 )
103.233.183.0/25 : 103.233.183.0 - 103.233.183.127
103.233.183.128/26 : 103.233.183.128 - 103.233.183.191
103.233.183.192/27 : 103.233.183.192 - 103.233.183.223
103.233.183.224/28 : 103.233.183.224 - 103.233.183.239
103.233.183.240/29 : 103.233.183.240 - 103.233.183.247
103.233.183.248/30 : 103.233.183.248 - 103.233.183.251
103.233.183.252/31 : 103.233.183.252 - 103.233.183.253
103.233.183.254/32 : 103.233.183.254 - 103.233.183.254

function cidr_conv($cidr_address) {
  $first = substr($cidr_address, 0, strpos($cidr_address, "/"));
  $netmask = substr(strstr($cidr_address, "/"), 1);  $first_bin = str_pad(decbin(ip2long($first)), 32, "0", STR_PAD_LEFT);
  $netmask_bin = str_pad(str_repeat("1", (integer)$netmask), 32, "0", STR_PAD_RIGHT);

  for ($i = 0; $i < 32; $i++) {
    if ($netmask_bin[$i] == "1")
      $last_bin .= $first_bin[$i];
    else
      $last_bin .= "1";
  }  $last = long2ip(bindec($last_bin));  return "$first - $last";
}

$r = ip2cidr("103.233.183.0", "103.233.183.255");
print_r($r);function ip2cidr($ip_start,$ip_end) {
  $res = array();
  if(long2ip(ip2long($ip_start))!=$ip_start or long2ip(ip2long($ip_end))!=$ip_end)
    return !trigger_error('ip 不合法', E_USER_NOTICE);
  $ipl_start = ip2long($ip_start);
  if($ipl_start < 0) $ipl_start += 0x100000000;  $ipl_end = ip2long($ip_end);
  if($ipl_end<0) $ipl_end += 0x100000000;  $ipl=$ipl_start;
  do {
    $k = strrpos(sprintf('%032b', $ipl), '1');
    $cidr = $k + 1;
    $dk = pow(2, 32-$k-1);
    if($ipl + $dk > $ipl_end + 1) { $dk /= 2; $cidr++; }
    $mask = $dk - 1;
    $res[] = array(
      'cidr' => sprintf("%s/%d", long2ip($ipl & ~$mask), $cidr),
      'mask' => long2ip(~$mask),
      'net' => long2ip($ipl & ~$mask),
      'usable' => $mask - 1,
      'start' => long2ip(($ipl & ~$mask) + 1),
      'end' => long2ip(($ipl | $mask) - 1),
      'broadcast' => long2ip($ipl | $mask),
    );
    $ipl += $dk;
  }while($ipl < $ipl_end);
  return $res;
}Array
(
    [0] => Array
        (
            [cidr] => 103.233.183.0/24
            [mask] => 255.255.255.0
            [net] => 103.233.183.0
            [usable] => 254
            [start] => 103.233.183.1
            [end] => 103.233.183.254
            [broadcast] => 103.233.183.255
        ))

$r = ip2cidr("210.80.0.0", "210.80.63.255");
print_r($r);Array
(
      [0] => Array
      (
              [cidr] => 210.80.0.0/13
              [mask] => 255.248.0.0
              [net] => 210.80.0.0
              [usable] => 524286
              [start] => 210.80.0.1
              [end] => 210.87.255.254
              [broadcast] => 210.87.255.255
       )
)
这块就存在BUG了  您看下12楼的方法是否合适

最终函数：
$CIDR2MASK = array( 0x00000000, 0x80000000,
        0xC0000000, 0xE0000000, 0xF0000000, 0xF8000000, 0xFC000000,
        0xFE000000, 0xFF000000, 0xFF800000, 0xFFC00000, 0xFFE00000,
        0xFFF00000, 0xFFF80000, 0xFFFC0000, 0xFFFE0000, 0xFFFF0000,
        0xFFFF8000, 0xFFFFC000, 0xFFFFE000, 0xFFFFF000, 0xFFFFF800,
        0xFFFFFC00, 0xFFFFFE00, 0xFFFFFF00, 0xFFFFFF80, 0xFFFFFFC0,
        0xFFFFFFE0, 0xFFFFFFF0, 0xFFFFFFF8, 0xFFFFFFFC, 0xFFFFFFFE,
        0xFFFFFFFF );

function ipTocidr($ip_start,$ip_end)
{
global $CIDR2MASK;
  $StartIp = ip2long($ip_start);
  $EndIp = ip2long($ip_end);
  $pairs = array();
  while ( $EndIp >= $StartIp )
  {
      $maxsize = 32;
      while ( $maxsize > 0)
      {
          $mask = $CIDR2MASK[$maxsize-1];
          $maskedBase = $StartIp & $mask ;
          if ( $maskedBase != $StartIp )
          {
             break;
          }
          $maxsize--;
      }
      $x = log( $EndIp -  $StartIp + 1) / log(2);
      $maxdiff = 32 - floor($x) ;
      if ( $maxsize < $maxdiff)
      {
          $maxsize = $maxdiff;
      }
      $ip = long2ip($StartIp);
      $pairs[] = $ip."/".$maxsize;
      $StartIp += pow( 2, (32 - $maxsize) );
  }
  return $pairs;
}
谢谢版主大大的悉心指导，最后还是将JAVA的函数翻译了

解决方案 »