生命不止,继续 go go go!!!
之前,有介绍过golang提供的标准库:net包
Go语言学习之net包(The way to go)
func ParseIP
func ParseIP(s string) IP
ParseIP parses s as an IP address, returning the result. The string s can be in dotted decimal (“192.0.2.1”) or IPv6 (“2001:db8::68”) form. If s is not a valid textual representation of an IP address, ParseIP returns nil.
func InterfaceAddrs
func InterfaceAddrs() ([]Addr, error)
InterfaceAddrs returns a list of the system’s unicast interface addresses.
The returned list does not identify the associated interface; use Interfaces and Interface.Addrs for more detail.
type IPNet
An IPNet represents an IP network.
type IPNet struct {
IP IP // network number
Mask IPMask // network mask
}
type IP
An IP is a single IP address, a slice of bytes. Functions in this package accept either 4-byte (IPv4) or 16-byte (IPv6) slices as input.
Note that in this documentation, referring to an IP address as an IPv4 address or an IPv6 address is a semantic property of the address, not just the length of the byte slice: a 16-byte slice can still be an IPv4 address.
type IP []byte
func IPv4
func IPv4(a, b, c, d byte) IP
IPv4 returns the IP address (in 16-byte form) of the IPv4 address a.b.c.d.
点到为止,更详细的请看文档:https://golang.org/pkg/net
tcp/ip协议中,专门保留了三个IP地址区域作为私有地址,其地址范围如下:
10.0.0.0/8:10.0.0.0~10.255.255.255
172.16.0.0/12:172.16.0.0~172.31.255.255
192.168.0.0/16:192.168.0.0~192.168.255.255
什么是内网IP
一些小型企业或者学校,通常都是申请一个固定的IP地址,然后通过IP共享(IP Sharing),使用整个公司或学校的机器都能够访问互联网。而这些企业或学校的机器使用的IP地址就是内网IP,内网IP是在规划IPv4协议时,考虑到IP地址资源可能不足,就专门为内部网设计私有IP地址(或称之为保留地址),一般常用内网IP地址都是这种形式的:10.X.X.X、172.16.X.X-172.31.X.X、192.168.X.X等。需要注意的是,内网的计算机可向Internet上的其他计算机发送连接请求,但Internet上其他的计算机无法向内网的计算机发送连接请求。我们平时可能在内网机器上搭建过网站或者FTP服务器,而在外网是不能访问该网站和FTP服务器的,原因就在于此。
什么是公网IP
公网IP就是除了保留IP地址以外的IP地址,可以与Internet上的其他计算机随意互相访问。我们通常所说的IP地址,其实就是指的公网IP。互联网上的每台计算机都有一个独立的IP地址,该IP地址唯一确定互联网上的一台计算机。这里的IP地址就是指的公网IP地址。
怎样理解互联网上的每台计算机都有一个唯一的IP地址
其实,互联网上的计算机是通过“公网IP+内网IP”来唯一确定的,就像很多大楼都是201房间一样,房间号可能一样,但是大楼肯定是唯一的。公网IP地址和内网IP地址也是同样,不同企业或学校的机器可能有相同的内网IP地址,但是他们的公网IP地址肯定不同。那么这些企业或学校的计算机是怎样IP地址共享的呢?这就需要使用NAT(Network Address Translation,网络地址转换)功能。当内部计算机要连接互联网时,首先需要通过NAT技术,将内部计算机数据包中有关IP地址的设置都设成NAT主机的公共IP地址,然后再传送到Internet,虽然内部计算机使用的是私有IP地址,但在连接Internet时,就可以通过NAT主机的NAT技术,将内网我IP地址修改为公网IP地址,如此一来,内网计算机就可以向Internet请求数据了。
百度ip,即可查看公网ip
curl命令查看公网ip
curl ipinfo.io/ip
通过http://myexternalip.com/raw获取公网ip
func get_external() string {
resp, err := http.Get("http://myexternalip.com/raw")
if err != nil {
return ""
}
defer resp.Body.Close()
content, _ := ioutil.ReadAll(resp.Body)
//buf := new(bytes.Buffer)
//buf.ReadFrom(resp.Body)
//s := buf.String()
return string(content)
}
func GetIntranetIp() {
addrs, err := net.InterfaceAddrs()
if err != nil {
fmt.Println(err)
os.Exit(1)
}
for _, address := range addrs {
// 检查ip地址判断是否回环地址
if ipnet, ok := address.(*net.IPNet); ok && !ipnet.IP.IsLoopback() {
if ipnet.IP.To4() != nil {
fmt.Println("ip:", ipnet.IP.String())
}
}
}
}
通过dns服务器8.8.8.8:80获取使用的ip
func GetPulicIP() string {
conn, _ := net.Dial("udp", "8.8.8.8:80")
defer conn.Close()
localAddr := conn.LocalAddr().String()
idx := strings.LastIndex(localAddr, ":")
return localAddr[0:idx]
}
func IsPublicIP(IP net.IP) bool {
if IP.IsLoopback() || IP.IsLinkLocalMulticast() || IP.IsLinkLocalUnicast() {
return false
}
if ip4 := IP.To4(); ip4 != nil {
switch true {
case ip4[0] == 10:
return false
case ip4[0] == 172 && ip4[1] >= 16 && ip4[1] <= 31:
return false
case ip4[0] == 192 && ip4[1] == 168:
return false
default:
return true
}
}
return false
}
func inet_aton(ipnr net.IP) int64 {
bits := strings.Split(ipnr.String(), ".")
b0, _ := strconv.Atoi(bits[0])
b1, _ := strconv.Atoi(bits[1])
b2, _ := strconv.Atoi(bits[2])
b3, _ := strconv.Atoi(bits[3])
var sum int64
sum += int64(b0) << 24
sum += int64(b1) << 16
sum += int64(b2) << 8
sum += int64(b3)
return sum
}
func inet_ntoa(ipnr int64) net.IP {
var bytes [4]byte
bytes[0] = byte(ipnr & 0xFF)
bytes[1] = byte((ipnr >> 8) & 0xFF)
bytes[2] = byte((ipnr >> 16) & 0xFF)
bytes[3] = byte((ipnr >> 24) & 0xFF)
return net.IPv4(bytes[3], bytes[2], bytes[1], bytes[0])
}
func IpBetween(from net.IP, to net.IP, test net.IP) bool {
if from == nil || to == nil || test == nil {
fmt.Println("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 {
fmt.Println("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
}
接口:
http://ip.taobao.com/service/getIpInfo.php?ip=
type IPInfo struct {
Code int `json:"code"`
Data IP `json:"data`
}
type IP struct {
Country string `json:"country"`
CountryId string `json:"country_id"`
Area string `json:"area"`
AreaId string `json:"area_id"`
Region string `json:"region"`
RegionId string `json:"region_id"`
City string `json:"city"`
CityId string `json:"city_id"`
Isp string `json:"isp"`
}
func TabaoAPI(ip string) *IPInfo {
url := "http://ip.taobao.com/service/getIpInfo.php?ip="
url += ip
resp, err := http.Get(url)
if err != nil {
return nil
}
defer resp.Body.Close()
out, err := ioutil.ReadAll(resp.Body)
if err != nil {
return nil
}
var result IPInfo
if err := json.Unmarshal(out, &result); err != nil {
return nil
}
return &result
}
package main
import (
"bytes"
"encoding/json"
"fmt"
"io/ioutil"
"net"
"net/http"
"os"
"strconv"
"strings"
)
type IPInfo struct {
Code int `json:"code"`
Data IP `json:"data`
}
type IP struct {
Country string `json:"country"`
CountryId string `json:"country_id"`
Area string `json:"area"`
AreaId string `json:"area_id"`
Region string `json:"region"`
RegionId string `json:"region_id"`
City string `json:"city"`
CityId string `json:"city_id"`
Isp string `json:"isp"`
}
func main() {
external_ip := get_external()
external_ip = strings.Replace(external_ip, "\n", "", -1)
fmt.Println("公网ip是: ", external_ip)
fmt.Println("------Dividing Line------")
ip := net.ParseIP(external_ip)
if ip == nil {
fmt.Println("您输入的不是有效的IP地址,请重新输入!")
} else {
result := TabaoAPI(string(external_ip))
if result != nil {
fmt.Println("国家:", result.Data.Country)
fmt.Println("地区:", result.Data.Area)
fmt.Println("城市:", result.Data.City)
fmt.Println("运营商:", result.Data.Isp)
}
}
fmt.Println("------Dividing Line------")
GetIntranetIp()
fmt.Println("------Dividing Line------")
ip_int := inet_aton(net.ParseIP(external_ip))
fmt.Println("Convert IPv4 address to decimal number(base 10) :", ip_int)
ip_result := inet_ntoa(ip_int)
fmt.Println("Convert decimal number(base 10) to IPv4 address:", ip_result)
fmt.Println("------Dividing Line------")
is_between := IpBetween(net.ParseIP("0.0.0.0"), net.ParseIP("255.255.255.255"), net.ParseIP(external_ip))
fmt.Println("check result: ", is_between)
fmt.Println("------Dividing Line------")
is_public_ip := IsPublicIP(net.ParseIP(external_ip))
fmt.Println("It is public ip: ", is_public_ip)
is_public_ip = IsPublicIP(net.ParseIP("169.254.85.131"))
fmt.Println("It is public ip: ", is_public_ip)
fmt.Println("------Dividing Line------")
fmt.Println(GetPulicIP())
}
func get_external() string {
resp, err := http.Get("http://myexternalip.com/raw")
if err != nil {
return ""
}
defer resp.Body.Close()
content, _ := ioutil.ReadAll(resp.Body)
buf := new(bytes.Buffer)
buf.ReadFrom(resp.Body)
//s := buf.String()
return string(content)
}
func GetIntranetIp() {
addrs, err := net.InterfaceAddrs()
if err != nil {
fmt.Println(err)
os.Exit(1)
}
for _, address := range addrs {
// 检查ip地址判断是否回环地址
if ipnet, ok := address.(*net.IPNet); ok && !ipnet.IP.IsLoopback() {
if ipnet.IP.To4() != nil {
fmt.Println("ip:", ipnet.IP.String())
}
}
}
}
func TabaoAPI(ip string) *IPInfo {
url := "http://ip.taobao.com/service/getIpInfo.php?ip="
url += ip
resp, err := http.Get(url)
if err != nil {
return nil
}
defer resp.Body.Close()
out, err := ioutil.ReadAll(resp.Body)
if err != nil {
return nil
}
var result IPInfo
if err := json.Unmarshal(out, &result); err != nil {
return nil
}
return &result
}
func inet_ntoa(ipnr int64) net.IP {
var bytes [4]byte
bytes[0] = byte(ipnr & 0xFF)
bytes[1] = byte((ipnr >> 8) & 0xFF)
bytes[2] = byte((ipnr >> 16) & 0xFF)
bytes[3] = byte((ipnr >> 24) & 0xFF)
return net.IPv4(bytes[3], bytes[2], bytes[1], bytes[0])
}
func inet_aton(ipnr net.IP) int64 {
bits := strings.Split(ipnr.String(), ".")
b0, _ := strconv.Atoi(bits[0])
b1, _ := strconv.Atoi(bits[1])
b2, _ := strconv.Atoi(bits[2])
b3, _ := strconv.Atoi(bits[3])
var sum int64
sum += int64(b0) << 24
sum += int64(b1) << 16
sum += int64(b2) << 8
sum += int64(b3)
return sum
}
func IpBetween(from net.IP, to net.IP, test net.IP) bool {
if from == nil || to == nil || test == nil {
fmt.Println("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 {
fmt.Println("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
}
func IsPublicIP(IP net.IP) bool {
if IP.IsLoopback() || IP.IsLinkLocalMulticast() || IP.IsLinkLocalUnicast() {
return false
}
if ip4 := IP.To4(); ip4 != nil {
switch true {
case ip4[0] == 10:
return false
case ip4[0] == 172 && ip4[1] >= 16 && ip4[1] <= 31:
return false
case ip4[0] == 192 && ip4[1] == 168:
return false
default:
return true
}
}
return false
}
func GetPulicIP() string {
conn, _ := net.Dial("udp", "8.8.8.8:80")
defer conn.Close()
localAddr := conn.LocalAddr().String()
idx := strings.LastIndex(localAddr, ":")
return localAddr[0:idx]
}
输出:
公网ip是: 222.128.17*.***
------Dividing Line------
国家: 中国
地区: 华北
城市: 北京市
运营商: 联通
------Dividing Line------
ip: 169.254.85.131
ip: 169.254.64.29
ip: 169.254.211.178
ip: 192.168.106.1
ip: 192.168.154.1
ip: 169.254.212.223
ip: 192.168.10.26
ip: 169.254.63.20
------Dividing Line------
Convert IPv4 address to decimal number(base 10) : 373297****
Convert decimal number(base 10) to IPv4 address: 222.128.17*.***
------Dividing Line------
check result: true
------Dividing Line------
It is public ip: true
It is public ip: false
------Dividing Line------
192.168.10.26