Go-OpenWrt获取wan口ip、dns、网关ip
1. 前言
一般来说，Openwrt可以配置多个wan口和多个lan口，这里获取的wan口的ip、dns等信息是基于知道wan口名称的前提下使用ifstatus命令来获取解析结果的。
2. 解决方案思路
通过uci命令获取相关网络接口名称，然后利用ifstatus查看对应接口的网络信息后获取，当然也可以直接通过uci接口获取：
root@OpenWrt:~# uci show network
network.loopback=interface
network.loopback.ifname='lo'
network.loopback.proto='static'
network.loopback.ipaddr='127.0.0.1'
network.loopback.netmask='255.0.0.0'
network.globals=globals
network.globals.ula_prefix='fdcd:b3fe:8353::/48'
network.lan=interface
network.lan.type='bridge'
network.lan.proto='static'
network.lan.netmask='255.255.255.0'
network.lan.ip6assign='60'
network.lan.ipaddr='40.40.40.100'
network.lan.ifname='eth1 eth2 eth3 eth4'
network.wan=interface
network.wan.ifname='eth7'
network.wan.proto='dhcp'
network.wan_eth=interface
network.wan_eth.ifname='eth0'
network.wan_eth.proto='static'
network.wan_eth.netmask='255.255.255.0'
network.wan_eth.gateway='192.168.67.254'
network.wan_eth.dns='8.8.8.8'
network.wan_eth.ipaddr='192.168.67.87'
network.SFP1=interface
network.SFP1.ifname='eth5'
network.SFP1.proto='static'
network.SFP1.netmask='255.255.255.0'
network.SFP1.dns='8.8.8.8'
network.SFP1.ipaddr='192.168.67.88'
network.SFP1.gateway='192.168.67.1'
root@OpenWrt:~# uci show network.SFP1.ipaddr
network.SFP1.ipaddr='192.168.67.88'
root@OpenWrt:~# ifstatus SFP1
{
"up": true,
"pending": false,
"available": true,
"autostart": true,
"dynamic": false,
"uptime": 1629,
"l3_device": "eth5",
"proto": "static",
"device": "eth5",
"updated": [
"addresses",
"routes"
],
"metric": 0,
"dns_metric": 0,
"delegation": true,
"ipv4-address": [
{
"address": "192.168.67.88",
"mask": 24
}
],
"ipv6-address": [
],
"ipv6-prefix": [
],
"ipv6-prefix-assignment": [
],
"route": [
{
"target": "0.0.0.0",
"mask": 0,
"nexthop": "192.168.67.1",
"source": "0.0.0.0/0"
}
],
"dns-server": [
"8.8.8.8"
],
"dns-search": [
],
"neighbors": [
],
"inactive": {
"ipv4-address": [
],
"ipv6-address": [
],
"route": [
],
"dns-server": [
],
"dns-search": [
],
"neighbors": [
]
},
"data": {
}
}
所以看使用场景决定使用哪种方式，对于OpenWrt来说uci是非常方便且实用的，所以遇到一些问题时首先考虑uci方式是否可行。
3. 代码
uci方式就不说了，利用相关语言的uci库进行处理即可，实在不行调用shell执行uci命令处理也可以，算是比较简单，这里就不多说了，这里主要给一下实用ifstatus命令获取信息的代码，也是通过ifstatus命令执行后将结果进行处理，由于结果为json形式，所以处理起来是比较方便的（给一个json转go结构体的网站，很方便：https://mholt.github.io/json-to-go/）：
type ifStatus struct {
Up bool `json:"up"`
Pending bool `json:"pending"`
Available bool `json:"available"`
Autostart bool `json:"autostart"`
Dynamic bool `json:"dynamic"`
Uptime int `json:"uptime"`
L3Device string `json:"l3_device"`
Proto string `json:"proto"`
Device string `json:"device"`
Updated []string `json:"updated"`
Metric int `json:"metric"`
DNSMetric int `json:"dns_metric"`
Delegation bool `json:"delegation"`
Ipv4Address []struct {
Address string `json:"address"`
Mask int `json:"mask"`
} `json:"ipv4-address"`
Ipv6Address []interface{} `json:"ipv6-address"`
Ipv6Prefix []interface{} `json:"ipv6-prefix"`
Ipv6PrefixAssignment []interface{} `json:"ipv6-prefix-assignment"`
Route []struct {
Target string `json:"target"`
Mask int `json:"mask"`
Nexthop string `json:"nexthop"`
Source string `json:"source"`
} `json:"route"`
DNSServer []string `json:"dns-server"`
DNSSearch []interface{} `json:"dns-search"`
Neighbors []interface{} `json:"neighbors"`
Inactive struct {
Ipv4Address []interface{} `json:"ipv4-address"`
Ipv6Address []interface{} `json:"ipv6-address"`
Route []interface{} `json:"route"`
DNSServer []interface{} `json:"dns-server"`
DNSSearch []interface{} `json:"dns-search"`
Neighbors []interface{} `json:"neighbors"`
} `json:"inactive"`
Data struct {
Leasetime int `json:"leasetime"`
} `json:"data"`
}
type WanInfo struct {
Ipv4Address string
Gateway string
DNS1 string
DNS2 string
}
func GetWanIpDNSGateway(wanName string) (*WanInfo, error) {
cmd := exec.Command("ifstatus", wanName)
output, err := cmd.CombinedOutput()
if err != nil {
logger.Error(err)
return nil, err
}
logger.Debug(string(output))
jsonRes := ifStatus{}
err = json.Unmarshal(output, &jsonRes)
if err != nil {
logger.Error(err)
return nil, err
}
wanInfo := &WanInfo{}
wanInfo.Ipv4Address = jsonRes.Ipv4Address[0].Address
wanInfo.Gateway = jsonRes.Route[0].Nexthop
for i := 0; i < len(jsonRes.DNSServer); i++ {
switch i {
case 0:
wanInfo.DNS1 = jsonRes.DNSServer[0]
case 1:
wanInfo.DNS2 = jsonRes.DNSServer[1]
}
}
return wanInfo, nil
}
//一般就是uci中查找出来的network中interfaced的wan口名称
wanInfo, err := utils.GetWanIpDNSGateway(interfaceWan)
if err != nil {
logger.Error(err)
return nil, err
}
res.Ipaddr = wanInfo.Ipv4Address
res.Gateway = wanInfo.Gateway
if wanInfo.DNS1 != "" {
res.Dns1 = wanInfo.DNS1
}
if wanInfo.DNS2 != "" {
res.Dns2 = wanInfo.DNS2
}
