Migrate to Kea DHCPv4 Server

docker-compose.yaml

@@ -8,11 +8,10 @@ services:
     image: metalstack/metal-bmc:latest
     network_mode: host
     volumes:
-      - ${PWD}/dhcpd.leases:/dhcpd.leases
+      - ${PWD}/kea-leases.csv:/kea-leases.csv
     environment:
-      METAL_BMC_LEASE_FILE: /dhcpd.leases
+      METAL_BMC_LEASE_FILE: /kea-leases.csv
       METAL_BMC_PARTITION_ID: partition
       METAL_BMC_METAL_API_URL: http://localhost:8080
       METAL_BMC_METAL_API_HMAC_KEY: test
       METAL_BMC_IGNORE_MACS: "aa:aa:aa:aa:aa:aa"
-

internal/leases/leases.go

@@ -29,10 +29,13 @@ func (l Leases) LatestByMac() map[string]Lease {
 	return byMac
 }
 
-func ReadLeases(leaseFile string) (Leases, error) {
-	leasesContent, err := os.ReadFile(leaseFile)
+func ReadLeases(filename string) (Leases, error) {
+	file, err := os.Open(filename)
 	if err != nil {
 		return nil, err
 	}
-	return parse(string(leasesContent))
+	defer func(file *os.File) {
+		_ = file.Close()
+	}(file)
+	return parse(file)
 }

internal/leases/leases_test.go

@@ -1,6 +1,7 @@
 package leases
 
 import (
+	"strings"
 	"testing"
 	"time"
 
@@ -9,7 +10,7 @@ import (
 )
 
 func TestFilterActive(t *testing.T) {
-	l, err := parse(sampleLeaseContent)
+	l, err := parse(strings.NewReader(sampleLeaseContent))
 	require.NoError(t, err)
 	assert.Equal(t, Leases{}, l.FilterActive())
 }

internal/leases/parser.go

@@ -1,47 +1,80 @@
 package leases
 
 import (
+	"encoding/csv"
 	"errors"
-	"regexp"
+	"fmt"
+	"io"
+	"strconv"
+	"strings"
 	"time"
 )
 
-const (
-	leaseDateFormat = "2006/01/02 15:04:05"
-	leaseRegex      = `(?ms)lease\s+(?P<ip>[^\s]+)\s+{.*?starts\s\d+\s(?P<begin>[\d\/]+\s[\d\:]+);.*?ends\s\d+\s(?P<end>[\d\/]+\s[\d\:]+);.*?hardware\sethernet\s(?P<mac>[\w\:]+);.*?}`
-)
+func parse(r io.Reader) (Leases, error) {
+	reader := csv.NewReader(r)
+
+	header, err := reader.Read()
+	if err != nil {
+		return nil, fmt.Errorf("failed to read header: %w", err)
+	}
+
+	if len(header) < 5 || header[0] != "address" || header[1] != "hwaddr" {
+		return nil, fmt.Errorf("invalid Kea lease file format")
+	}
 
-func parse(contents string) (Leases, error) {
-	leases := Leases{}
-	var re = regexp.MustCompile(leaseRegex)
-	matches := re.FindAllStringSubmatch(contents, -1)
+	var leases Leases
 	var errs []error
-	for _, m := range matches {
-		rm := make(map[string]string)
-		for i, name := range re.SubexpNames() {
-			if i != 0 && name != "" {
-				rm[name] = m[i]
-			}
+
+	for {
+		record, err := reader.Read()
+		if err == io.EOF {
+			break
 		}
-		begin, err := time.Parse(leaseDateFormat, rm["begin"])
 		if err != nil {
-			errs = append(errs, err)
+			line, _ := reader.FieldPos(0)
+			errs = append(errs, fmt.Errorf("line %d: failed to read CSV record: %v", line, err))
+			continue
+		}
+
+		if len(record) < 5 {
+			line, _ := reader.FieldPos(0)
+			errs = append(errs, fmt.Errorf("line %d: incomplete record, expected at least 5 fields, got %d", line, len(record)))
+			continue
 		}
-		end, err := time.Parse(leaseDateFormat, rm["end"])
+
+		expireStr := strings.TrimSpace(record[4])
+		expireTs, err := strconv.ParseInt(expireStr, 10, 64)
 		if err != nil {
-			errs = append(errs, err)
+			line, col := reader.FieldPos(4)
+			errs = append(errs, fmt.Errorf("line %d, column %d: invalid expire timestamp '%s': %v", line, col, expireStr, err))
+			continue
+		}
+
+		ip := strings.TrimSpace(record[0])
+		if ip == "" {
+			line, col := reader.FieldPos(0)
+			errs = append(errs, fmt.Errorf("line %d, column %d: empty Ip address", line, col))
+			continue
 		}
 
-		l := Lease{
-			Mac:   rm["mac"],
-			Ip:    rm["ip"],
-			Begin: begin,
-			End:   end,
+		mac := strings.TrimSpace(record[1])
+		if mac == "" {
+			line, col := reader.FieldPos(1)
+			errs = append(errs, fmt.Errorf("line %d, column %d: empty Mac address", line, col))
+			continue
 		}
-		leases = append(leases, l)
+
+		lease := Lease{
+			Mac: mac,
+			Ip:  ip,
+			End: time.Unix(expireTs, 0),
+		}
+		leases = append(leases, lease)
 	}
+
 	if len(errs) > 0 {
 		return leases, errors.Join(errs...)
 	}
+
 	return leases, nil
 }

internal/leases/parser_test.go

@@ -1,58 +1,33 @@
 package leases
 
 import (
+	"strings"
 	"testing"
 	"time"
 
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 )
 
-var sampleLeaseContent = `
-lease 192.168.2.27 {
-	starts 4 2019/06/27 13:30:21;
-	ends 4 2019/06/27 13:40:21;
-	cltt 4 2019/06/27 13:30:21;
-	binding state active;
-	next binding state free;
-	rewind binding state free;
-	hardware ethernet ac:1f:6b:35:ac:62;
-	uid "\001\254\037k5\254b";
-	set vendor-class-identifier = "udhcp 1.23.1";
-}
-lease 192.168.2.30 {
-	starts 4 2019/06/27 06:40:06;
-	ends 4 2019/06/27 06:50:06;
-	cltt 4 2019/06/27 06:40:06;
-	binding state active;
-	next binding state free;
-	rewind binding state free;
-	hardware ethernet ac:1f:6b:35:ab:2d;
-	uid "\001\254\037k5\253-";
-	set vendor-class-identifier = "udhcp 1.23.1";
-}
+var sampleLeaseContent = `address,hwaddr,client_id,valid_lifetime,expire,subnet_id,fqdn_fwd,fqdn_rev,hostname,state,user_context
+192.168.2.27,ac:1f:6b:35:ac:62,01:ac:1f:6b:35:ac:62,3600,1593243021,1,0,0,,1,
+192.168.2.30,ac:1f:6b:35:ab:2d,01:ac:1f:6b:35:ab:2d,3600,1593243006,1,0,0,,1,
 `
 
 func TestParse(t *testing.T) {
-	l, err := parse(sampleLeaseContent)
+	l, err := parse(strings.NewReader(sampleLeaseContent))
 	require.NoError(t, err)
 
-	b, _ := time.Parse(leaseDateFormat, "2019/06/27 13:30:21")
-	e, _ := time.Parse(leaseDateFormat, "2019/06/27 13:40:21")
 	lease1 := Lease{
-		Mac:   "ac:1f:6b:35:ac:62",
-		Ip:    "192.168.2.27",
-		Begin: b,
-		End:   e,
+		Mac: "ac:1f:6b:35:ac:62",
+		Ip:  "192.168.2.27",
+		End: time.Unix(1593243021, 0),
 	}
 
-	b, _ = time.Parse(leaseDateFormat, "2019/06/27 06:40:06")
-	e, _ = time.Parse(leaseDateFormat, "2019/06/27 06:50:06")
 	lease2 := Lease{
-		Mac:   "ac:1f:6b:35:ab:2d",
-		Ip:    "192.168.2.30",
-		Begin: b,
-		End:   e,
+		Mac: "ac:1f:6b:35:ab:2d",
+		Ip:  "192.168.2.30",
+		End: time.Unix(1593243006, 0),
 	}
 
 	assert.Equal(t, Leases{lease1, lease2}, l)

internal/leases/types.go

@@ -8,10 +8,9 @@ import (
 )
 
 type Lease struct {
-	Mac   string
-	Ip    string
-	Begin time.Time
-	End   time.Time
+	Mac string
+	Ip  string
+	End time.Time
 }
 
 type Leases []Lease

kea-leases.csv

@@ -0,0 +1,3 @@
+address,hwaddr,client_id,valid_lifetime,expire,subnet_id,fqdn_fwd,fqdn_rev,hostname,state,user_context
+192.168.2.27,ac:1f:6b:35:ac:62,01:ac:1f:6b:35:ac:62,3600,1593243021,1,0,0,,1,
+192.168.2.30,ac:1f:6b:35:ab:2d,01:ac:1f:6b:35:ab:2d,3600,1593243006,1,0,0,,1,

pkg/config/config.go

@@ -12,7 +12,7 @@ type Config struct {
 	PartitionID string `required:"true" desc:"set the partition ID" envconfig:"partition_id"`
 
 	// ipmi details reporting parameters
-	LeaseFile       string        `required:"false" default:"/var/lib/dhcp/dhcpd.leases" desc:"the dhcp lease file to read" split_words:"true"`
+	LeaseFile       string        `required:"false" default:"/var/lib/kea/kea-leases.csv" desc:"the dhcp lease file to read" split_words:"true"`
 	ReportInterval  time.Duration `required:"false" default:"5m" desc:"the interval for periodical reports" split_words:"true"`
 	MetalAPIURL     *url.URL      `required:"true" desc:"endpoint for the metal-api" envconfig:"metal_api_url"`
 	MetalAPIHMACKey string        `required:"true" desc:"the preshared key for the hmac calculation" envconfig:"metal_api_hmac_key"`