Go/GoLang检查范围内的IP地址

Question

在Go/GoLang中,检查IP地址是否在特定范围内的最快方法是什么？

例如,给定的范围216.14.49.184来216.14.49.191,我将如何检查是否给定的输入的IP地址是在这个范围内？

Answer 1

IP地址[]byte在go(IP类型)中表示为bigendian 切片,因此将使用正确比较bytes.Compare.

例如(玩)

package main

import (
    "bytes"
    "fmt"
    "net"
)

var (
    ip1 = net.ParseIP("216.14.49.184")
    ip2 = net.ParseIP("216.14.49.191")
)

func check(ip string) bool {
    trial := net.ParseIP(ip)
    if trial.To4() == nil {
        fmt.Printf("%v is not an IPv4 address\n", trial)
        return false
    }
    if bytes.Compare(trial, ip1) >= 0 && bytes.Compare(trial, ip2) <= 0 {
        fmt.Printf("%v is between %v and %v\n", trial, ip1, ip2)
        return true
    }
    fmt.Printf("%v is NOT between %v and %v\n", trial, ip1, ip2)
    return false
}

func main() {
    check("1.2.3.4")
    check("216.14.49.185")
    check("1::16")
}

哪个产生

1.2.3.4 is NOT between 216.14.49.184 and 216.14.49.191
216.14.49.185 is between 216.14.49.184 and 216.14.49.191
1::16 is not an IPv4 address

Answer 2

这已经作为名为net.Contains的函数在"net"包中的stdlib中.你不需要重写已经存在的代码!

见文档这里.

要使用它,您只需要解析所需的子网

network := "192.168.5.0/24"
clientips := []string{
    "192.168.5.1",
    "192.168.6.0",
}
_, subnet, _ := net.ParseCIDR(network)
for _, clientip := range clientips {
    ip := net.ParseIP(clientip)
    if subnet.Contains(ip) {
        fmt.Println("IP in subnet", clientip)
    }
}

如果以上代码没有意义,这里是一个谷歌播放链接

Answer 3

ipv4/ipv6的通用版本.

ip.go:

package ip

import (
    "bytes"
    "net"

    "github.com/golang/glog"
)

//test to determine if a given ip is between two others (inclusive)
func IpBetween(from net.IP, to net.IP, test net.IP) bool {
    if from == nil || to == nil || test == nil {
        glog.Warning("An ip input is nil") // or return an error!?
        return false
    }

    from16 := from.To16()
    to16 := to.To16()
    test16 := test.To16()
    if from16 == nil || to16 == nil || test16 == nil {
        glog.Warning("An ip did not convert to a 16 byte") // or return an error!?
        return false
    }

    if bytes.Compare(test16, from16) >= 0 && bytes.Compare(test16, to16) <= 0 {
        return true
    }
    return false
}

和ip_test.go:

package ip

import (
    "net"
    "testing"
)

func TestIPBetween(t *testing.T) {
    HandleIpBetween(t, "0.0.0.0", "255.255.255.255", "128.128.128.128", true)
    HandleIpBetween(t, "0.0.0.0", "128.128.128.128", "255.255.255.255", false)
    HandleIpBetween(t, "74.50.153.0", "74.50.153.4", "74.50.153.0", true)
    HandleIpBetween(t, "74.50.153.0", "74.50.153.4", "74.50.153.4", true)
    HandleIpBetween(t, "74.50.153.0", "74.50.153.4", "74.50.153.5", false)
    HandleIpBetween(t, "2001:0db8:85a3:0000:0000:8a2e:0370:7334", "74.50.153.4", "74.50.153.2", false)
    HandleIpBetween(t, "2001:0db8:85a3:0000:0000:8a2e:0370:7334", "2001:0db8:85a3:0000:0000:8a2e:0370:8334", "2001:0db8:85a3:0000:0000:8a2e:0370:7334", true)
    HandleIpBetween(t, "2001:0db8:85a3:0000:0000:8a2e:0370:7334", "2001:0db8:85a3:0000:0000:8a2e:0370:8334", "2001:0db8:85a3:0000:0000:8a2e:0370:7350", true)
    HandleIpBetween(t, "2001:0db8:85a3:0000:0000:8a2e:0370:7334", "2001:0db8:85a3:0000:0000:8a2e:0370:8334", "2001:0db8:85a3:0000:0000:8a2e:0370:8334", true)
    HandleIpBetween(t, "2001:0db8:85a3:0000:0000:8a2e:0370:7334", "2001:0db8:85a3:0000:0000:8a2e:0370:8334", "2001:0db8:85a3:0000:0000:8a2e:0370:8335", false)
    HandleIpBetween(t, "::ffff:192.0.2.128", "::ffff:192.0.2.250", "::ffff:192.0.2.127", false)
    HandleIpBetween(t, "::ffff:192.0.2.128", "::ffff:192.0.2.250", "::ffff:192.0.2.128", true)
    HandleIpBetween(t, "::ffff:192.0.2.128", "::ffff:192.0.2.250", "::ffff:192.0.2.129", true)
    HandleIpBetween(t, "::ffff:192.0.2.128", "::ffff:192.0.2.250", "::ffff:192.0.2.250", true)
    HandleIpBetween(t, "::ffff:192.0.2.128", "::ffff:192.0.2.250", "::ffff:192.0.2.251", false)
    HandleIpBetween(t, "::ffff:192.0.2.128", "::ffff:192.0.2.250", "192.0.2.130", true)
    HandleIpBetween(t, "192.0.2.128", "192.0.2.250", "::ffff:192.0.2.130", true)
    HandleIpBetween(t, "idonotparse", "192.0.2.250", "::ffff:192.0.2.130", false)

}

func HandleIpBetween(t *testing.T, from string, to string, test string, assert bool) {
    res := IpBetween(net.ParseIP(from), net.ParseIP(to), net.ParseIP(test))
    if res != assert {
        t.Errorf("Assertion (have: %s should be: %s) failed on range %s-%s with test %s", res, assert, from, to, test)
    }
}