owrt/uci_firewall_custom_rules.go

package owrt

import (
	"fmt"
	"io/ioutil"
	"os"
	"strings"
)

// UCIFirewallCustomRule is the description of an Wireless interface (cf Openwrt doc) on top of an Wireless Device
type UCIFirewallCustomRule struct {
	Name string
	Rule string
	UCI  *UCI
}

// NewUCIFirewallCustomRule builds a new UCIFirewallCustomRule instance
func NewUCIFirewallCustomRule(client *UCI) *UCIFirewallCustomRule {
	return &UCIFirewallCustomRule{
		UCI: client,
	}
}

// Create add a new firewall rule in UCI Configuration
func (cr *UCIFirewallCustomRule) Create() error {

	var file *os.File
	customFWFile := cr.UCI.CustomFirewallFile

	fmt.Printf("DEBUG %s\n", customFWFile)
	_, stErr := os.Stat(customFWFile)
	if os.IsNotExist(stErr) {
		var err error
		file, err = os.Create(customFWFile)
		if err != nil {
			return err
		}
	} else {
		var oErr error
		file, oErr = os.OpenFile(customFWFile, os.O_RDWR, 0644)
		if oErr != nil {
			return oErr

		}
	}
	defer file.Close()

	line := fmt.Sprintf("%s # %s", cr.Rule, cr.Name)
	_, err := file.WriteString(line)
	return err
}

// Save commit and relaod configuration (writes it to files !)
func (cr *UCIFirewallCustomRule) Save() error {
	reload := cr.UCI.Reload()
	if reload.ReturnCode != 0 {
		return fmt.Errorf("%d - %s - %s - %s",
			reload.ReturnCode,
			reload.Command,
			reload.Stdout,
			reload.Stderr)
	}

	sErr := cr.UCI.Service("firewall", "restart")
	return sErr
}

// Delete remove wifi interface from UCI Configuration
func (cr *UCIFirewallCustomRule) Delete() error {
	input, err := ioutil.ReadFile(cr.UCI.CustomFirewallFile)
	if err != nil {
		return err
	}

	lines := strings.Split(string(input), "\n")
	var out []string
	for _, line := range lines {
		if !strings.Contains(line, cr.Name) {
			out = append(out, line)
		}
	}

	output := strings.Join(out, "\n")
	err = ioutil.WriteFile(cr.UCI.CustomFirewallFile, []byte(output), 0644)
	return err
}

// Update add a new entry for wifi interface in UCI Configuration
func (cr *UCIFirewallCustomRule) Update() error {
	input, err := ioutil.ReadFile(cr.UCI.CustomFirewallFile)
	if err != nil {
		return err
	}

	lines := strings.Split(string(input), "\n")
	var out []string
	for _, line := range lines {
		if strings.Contains(line, cr.Name) {
			nContent := fmt.Sprintf("%s # %s", cr.Rule, cr.Name)
			out = append(out, nContent)
		} else {
			out = append(out, line)
		}
	}

	output := strings.Join(out, "\n")
	err = ioutil.WriteFile(cr.UCI.CustomFirewallFile, []byte(output), 0644)
	return err
}