99 lines
1.9 KiB
Go
99 lines
1.9 KiB
Go
// On-disk database for lease table
|
|
|
|
package dhcpd
|
|
|
|
import (
|
|
"encoding/json"
|
|
"io/ioutil"
|
|
"net"
|
|
"os"
|
|
"time"
|
|
|
|
"github.com/AdguardTeam/golibs/file"
|
|
"github.com/AdguardTeam/golibs/log"
|
|
"github.com/krolaw/dhcp4"
|
|
)
|
|
|
|
const dbFilename = "leases.db"
|
|
|
|
type leaseJSON struct {
|
|
HWAddr []byte `json:"mac"`
|
|
IP []byte `json:"ip"`
|
|
Hostname string `json:"host"`
|
|
Expiry int64 `json:"exp"`
|
|
}
|
|
|
|
// Load lease table from DB
|
|
func (s *Server) dbLoad() {
|
|
data, err := ioutil.ReadFile(dbFilename)
|
|
if err != nil {
|
|
if !os.IsNotExist(err) {
|
|
log.Error("DHCP: can't read file %s: %v", dbFilename, err)
|
|
}
|
|
return
|
|
}
|
|
|
|
obj := []leaseJSON{}
|
|
err = json.Unmarshal(data, &obj)
|
|
if err != nil {
|
|
log.Error("DHCP: invalid DB: %v", err)
|
|
return
|
|
}
|
|
|
|
s.leases = nil
|
|
s.IPpool = make(map[[4]byte]net.HardwareAddr)
|
|
|
|
numLeases := len(obj)
|
|
for i := range obj {
|
|
|
|
if !dhcp4.IPInRange(s.leaseStart, s.leaseStop, obj[i].IP) {
|
|
log.Tracef("Skipping a lease with IP %s: not within current IP range", obj[i].IP)
|
|
continue
|
|
}
|
|
|
|
lease := Lease{
|
|
HWAddr: obj[i].HWAddr,
|
|
IP: obj[i].IP,
|
|
Hostname: obj[i].Hostname,
|
|
Expiry: time.Unix(obj[i].Expiry, 0),
|
|
}
|
|
|
|
s.leases = append(s.leases, &lease)
|
|
|
|
s.reserveIP(lease.IP, lease.HWAddr)
|
|
}
|
|
log.Info("DHCP: loaded %d leases from DB", numLeases)
|
|
}
|
|
|
|
// Store lease table in DB
|
|
func (s *Server) dbStore() {
|
|
var leases []leaseJSON
|
|
|
|
for i := range s.leases {
|
|
if s.leases[i].Expiry.Unix() == 0 {
|
|
continue
|
|
}
|
|
lease := leaseJSON{
|
|
HWAddr: s.leases[i].HWAddr,
|
|
IP: s.leases[i].IP,
|
|
Hostname: s.leases[i].Hostname,
|
|
Expiry: s.leases[i].Expiry.Unix(),
|
|
}
|
|
leases = append(leases, lease)
|
|
}
|
|
|
|
data, err := json.Marshal(leases)
|
|
if err != nil {
|
|
log.Error("json.Marshal: %v", err)
|
|
return
|
|
}
|
|
|
|
err = file.SafeWrite(dbFilename, data)
|
|
if err != nil {
|
|
log.Error("DHCP: can't store lease table on disk: %v filename: %s",
|
|
err, dbFilename)
|
|
return
|
|
}
|
|
log.Info("DHCP: stored %d leases in DB", len(leases))
|
|
}
|