입력 IP가 특정 IP 범위에 속하는지 확인하는 방법

입력 IP가 특정 IP 범위에 속하는지 확인하는 방법

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사용자가 몇 가지 IP 범위 (예 : 172.16.11.5-100)를 입력하도록 허용하면 IP (172.16.11.50)가 범위에 속하는지 확인하는 함수를 어떻게 작성할 수 있습니까?

.NET에 활용할 기존 라이브러리가 있습니까?

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프레임 워크에 내장 된 것은 없지만 IPAddressRange클래스 를 만드는 데 많은 노력이 들지 않습니다 .

하위 주소, 상위 주소 및 비교 주소에서 IPAddress.GetAddressBytes 를 호출하여 범위를 비교합니다. 첫 번째 바이트부터 비교 주소가 상위 / 하위 주소 범위에 있는지 확인합니다.

이 방법은 IPv4 및 IPv6 주소 모두에서 작동합니다.

public class IPAddressRange
{
    readonly AddressFamily addressFamily;
    readonly byte[] lowerBytes;
    readonly byte[] upperBytes;

    public IPAddressRange(IPAddress lowerInclusive, IPAddress upperInclusive)
    {
        // Assert that lower.AddressFamily == upper.AddressFamily

        this.addressFamily = lowerInclusive.AddressFamily;
        this.lowerBytes = lowerInclusive.GetAddressBytes();
        this.upperBytes = upperInclusive.GetAddressBytes();
    }

    public bool IsInRange(IPAddress address)
    {
        if (address.AddressFamily != addressFamily)
        {
            return false;
        }

        byte[] addressBytes = address.GetAddressBytes();

        bool lowerBoundary = true, upperBoundary = true;

        for (int i = 0; i < this.lowerBytes.Length && 
            (lowerBoundary || upperBoundary); i++)
        {
            if ((lowerBoundary && addressBytes[i] < lowerBytes[i]) ||
                (upperBoundary && addressBytes[i] > upperBytes[i]))
            {
                return false;
            }

            lowerBoundary &= (addressBytes[i] == lowerBytes[i]);
            upperBoundary &= (addressBytes[i] == upperBytes[i]);
        }

        return true;
    }
}

주의 : 위의 코드는 공개 정적 팩토리 메소드를 추가하기 위해 확장 될 수 있습니다. FromCidr(IPAddress address, int bits)

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"192.168.0.0/24"및 "192.168.0.0/255.255.255.0"및 "192.168.0.0-192.168.0.255"와 같은 IP 주소 문자열 범위를 구문 분석 할 수있는 @jsakamoto의이 라이브러리를 고려할 수 있습니다. , conatins 확인 가능. 이 라이브러리는 IPv4 및 IPv6를 모두 지원합니다.

https://github.com/jsakamoto/ipaddressrange

NuGet을 통해 설치할 수도 있습니다.

http://www.nuget.org/packages/IPAddressRange/

using NetTools;
...
// rangeA.Begin is "192.168.0.0", and rangeA.End is "192.168.0.255".
var rangeA = IPAddressRange.Parse("192.168.0.0/255.255.255.0");
rangeA.Contains(IPAddress.Parse("192.168.0.34")); // is True.
rangeA.Contains(IPAddress.Parse("192.168.10.1")); // is False.
rangeA.ToCidrString(); // is 192.168.0.0/24

// rangeB.Begin is "192.168.0.10", and rangeB.End is "192.168.10.20".
var rangeB1 = IPAddressRange.Parse("192.168.0.10 - 192.168.10.20");
rangeB1.Contains(IPAddress.Parse("192.168.3.45")); // is True.
rangeB1.Contains(IPAddress.Parse("192.168.0.9")); // is False.

// Support shortcut range description. 
// ("192.168.10.10-20" means range of begin:192.168.10.10 to end:192.168.10.20.)
var rangeB2 = IPAddressRange.Parse("192.168.10.10-20");

// Support CIDR expression and IPv6.
var rangeC = IPAddressRange.Parse("fe80::/10"); 
rangeC.Contains(IPAddress.Parse("fe80::d503:4ee:3882:c586%3")); // is True.
rangeC.Contains(IPAddress.Parse("::1")); // is False.

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public static bool IsInRange(string startIpAddr, string endIpAddr, string address)
{
    long ipStart = BitConverter.ToInt32(IPAddress.Parse(startIpAddr).GetAddressBytes().Reverse().ToArray(), 0);

    long ipEnd = BitConverter.ToInt32(IPAddress.Parse(endIpAddr).GetAddressBytes().Reverse().ToArray(), 0);

    long ip = BitConverter.ToInt32(IPAddress.Parse(address).GetAddressBytes().Reverse().ToArray(), 0);

    return ip >= ipStart && ip <= ipEnd; //edited
}

Console.WriteLine(IsInRange("100.0.0.1", "110.0.0.255", "102.0.0.4"));//true

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가장 좋은 방법은 이러한 주소를 정수로 변환 한 다음 비교를 수행하는 것입니다.

여기에서의 예 : IP에서 정수로

IP 주소를 정수로 변환하려면 4 개의 옥텟으로 나누십시오. 예를 들어 제공 한 IP 주소는 다음과 같이 나눌 수 있습니다.

First Octet:    217
Second Octet:   110
Third Octet:    18
Fourth Octet:   206

점으로 구분 된 문자열에서 10 진수 주소를 계산하려면 다음 계산을 수행하십시오.

    (first octet * 256³) + (second octet * 256²) + (third octet * 256) + (fourth octet)
=   (first octet * 16777216) + (second octet * 65536) + (third octet * 256) + (fourth octet)
=   (217 * 16777216) + (110 * 65536) + (18 * 256) + (206)
=   3647869646

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Considering IPv6, you can convert them to integers (128bit vs 32bit IPv4) as well. Have a look at this question: Formatting IPv6 as an int in C# and storing it in SQL Server

The simplest route is to get the framework to do this for you. Use IPAddress.Parse to parse the address, then IPAddress.GetAddressBytes to get the "number" as byte[].

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I used this code on codeproject before, which may be of use to you.

http://www.codeproject.com/KB/IP/ipnumbers.aspx

You have the possibility to add to IPList a range of IP numbers defined by a From IP and a To IP number. The method breaks up the range into standard IP ranges and finds their masks. So the range "10.0.0.5" to "10.0.0.20" will be broken up to the following ranges and added to the list: 10.0.0.5, 10.0.0.20, 10.0.0.6/31, 10.0.0.16/30 and 10.0.0.8/29 and you'll have the possibility to check against that.

Disclaimer: The Class is only tested with simple data sets, and the Class lacks validation of the IP numbers and IP masks provided. This should be fixed before it is used in production environments.

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reposting my answer from here

A while ago, I had to find the location of a given IP. We got the IP from the request. There are free databases which gave us this mapping. In IPv4, when we say the IP as "a.b.c.d" it is essentially a * (256^3) + b * (256^2) + c * (256) + d.

http://www.aboutmyip.com/AboutMyXApp/IP2Integer.jsp

so when you say you want an IP address starting with "a", you are looking for IPs between a * 256^ 3 and a * 256^3 + 256 * (256^2) (b = 256) + 256 *(256) (c=256) + 256( d=256) (lower / upper limit may vary a little bit depending on whether you want to include/exclude the limits).

That said, there are specific IPs reserved for specific purposes(like 127.0.0.1 which is localhost, 0.0.0.0 cannot be an IP etc).

So your linq query would be

from i in iList where i >= MIN && i <= MAX select i;

where iList is your initial list MIN is your min value for your range MAX is your max value for your range

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Could you figure out the subnet mask from your IP range?

If so then maybe you could use this IsInSameSubnet method..

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I want to +1 BuddhiP's answer above which recommends the IPAddressRange package from NuGet: https://www.nuget.org/packages/IPAddressRange/

But because code formatting is hard in a comment I'll just add a practical code example here on how to use IPAddressRange.

CheckIPWhitelist reads a setting called IPWhitelist and assumes a semi-colon delimited list of IP ranges (such as "192.168.10.10-20;192.168.125.1-150;192.168.123.1-150") that IPAddressRange can parse. The function iterates the ranges and will and return true if present, false if not found.

This function is VB.NET and assumes some ASP.NET dependencies are present (such as the System.Web.HttpRequest namespace)

Imports NetTools ' ref. https://www.nuget.org/packages/IPAddressRange/

Function CheckIPWhitelist() As Boolean
    Dim match As Boolean = False
    Dim SourceIP As String = Request.UserHostAddress()

    ' Examples of valid IPWhitelist ranges 
    ' one range in longhand range format: "192.168.0.10 - 192.168.10.20"
    ' one range in shorthand range format: "192.168.10.10-20"
    ' multiple ranges separated by semicolons in shorthand range format: "192.168.10.10-20;192.168.125.1-150;192.168.123.1-150"
    Dim IPWhitelist As String = ConfigurationManager.AppSettings("IPWhitelist")

    Dim arrRanges As String() = IPWhitelist.Split(";")
    For i As Integer = 0 To arrRanges.Length - 1
        If arrRanges(i) IsNot Nothing Then
            Dim range As NetTools.IPAddressRange = IPAddressRange.Parse(arrRanges(i))
            If range.Contains(IPAddressRange.Parse(SourceIP)) = True Then
                match = True ' IP is in the whitelist, set a boolean
                Exit For
            End If
        End If
    Next
    Return match
End Function

참고URL : https://stackoverflow.com/questions/2138706/how-to-check-a-input-ip-fall-in-a-specific-ip-range