router7/cmd/radvd/radvd.go

82 lines
1.9 KiB
Go

// Copyright 2018 Google Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
// Binary radvd sends IPv6 router advertisements.
package main
import (
"encoding/json"
"flag"
"io/ioutil"
"log"
"net"
"os"
"os/signal"
"path"
"syscall"
"github.com/rtr7/router7/internal/dhcp6"
"github.com/rtr7/router7/internal/radvd"
)
var perm = flag.String("perm", "/perm", "path to replace /perm")
func logic() error {
srv, err := radvd.NewServer()
if err != nil {
return err
}
readConfig := func() error {
b, err := ioutil.ReadFile(path.Join(*perm, "/dhcp6/wire/lease.json"))
if err != nil {
return err
}
var cfg dhcp6.Config
if err := json.Unmarshal(b, &cfg); err != nil {
return err
}
var additional []net.IPNet
if b, err := ioutil.ReadFile(path.Join(*perm, "/radvd/prefixes.json")); err == nil {
if err := json.Unmarshal(b, &additional); err != nil {
return err
}
}
srv.SetPrefixes(append(cfg.Prefixes, additional...))
return nil
}
if err := readConfig(); err != nil {
log.Printf("cannot announce IPv6 prefixes: %v", err)
}
ch := make(chan os.Signal, 1)
signal.Notify(ch, syscall.SIGUSR1)
go func() {
for range ch {
if err := readConfig(); err != nil {
log.Printf("readConfig: %v", err)
}
}
}()
return srv.ListenAndServe("lan0")
}
func main() {
// TODO: drop privileges, run as separate uid?
flag.Parse()
if err := logic(); err != nil {
log.Fatal(err)
}
}