check disk space when writing logs

pkg/wireguard/packetlogger.go

@@ -7,6 +7,7 @@ import (
 	"fmt"
 	"net"
 	"net/http"
+	"os"
 	"path"
 	"runtime"
 	"strconv"
@@ -18,6 +19,7 @@ import (
 	"github.com/in4it/wireguard-server/pkg/logging"
 	"github.com/in4it/wireguard-server/pkg/storage"
 	"github.com/packetcap/go-pcap"
+	"golang.org/x/sys/unix"
 )
 
 func RunPacketLogger(storage storage.Iface, clientCache *ClientCache) {
@@ -30,11 +32,20 @@ func RunPacketLogger(storage storage.Iface, clientCache *ClientCache) {
 		logging.ErrorLog(fmt.Errorf("can't start packet inspector: %s", err))
 		return
 	}
+	i := 0
 	for {
 		err := readPacket(storage, handle, clientCache)
 		if err != nil {
 			logging.DebugLog(fmt.Errorf("readPacket error: %s", err))
 		}
+		if i%1000 == 0 {
+			if err := checkDiskSpace(); err != nil {
+				logging.ErrorLog(fmt.Errorf("disk space error: %s", err))
+				return
+			}
+			i = 0
+		}
+		i++
 	}
 }
 func readPacket(storage storage.Iface, handle *pcap.Handle, clientCache *ClientCache) error {
@@ -94,7 +105,6 @@ func parsePacket(storage storage.Iface, data []byte, clientCache *ClientCache) e
 		switch tcpPacket.DstPort {
 		case 80:
 			if tcpPacket.DstPort == 80 {
-				//fmt.Printf("payload: %s", tcpPacket.LayerContents())
 				appLayer := packet.ApplicationLayer()
 				if appLayer != nil {
 					req, err := http.ReadRequest(bufio.NewReader(bytes.NewReader(appLayer.Payload())))
@@ -218,7 +228,6 @@ func parseTLSExtensionSNI(data []byte) []byte {
 
 			if serverNameExtensionLength > 0 && entryType == 0 && len(data) > 8 { // 0 = DNS hostname
 				hostnameLength := binary.BigEndian.Uint16(data[7:9])
-				fmt.Printf("extensionType: %d length: %d; slice: %d\n", extensionType, serverNameExtensionLength, 9+hostnameLength)
 				if len(data) > int(8+hostnameLength) {
 					return data[9 : 9+hostnameLength]
 				}
@@ -228,3 +237,22 @@ func parseTLSExtensionSNI(data []byte) []byte {
 	}
 	return nil
 }
+
+func checkDiskSpace() error {
+	var stat unix.Statfs_t
+
+	wd, err := os.Getwd()
+	if err != nil {
+		fmt.Printf("cannot get cwd: %s", err)
+	}
+	unix.Statfs(wd, &stat)
+	if stat.Blocks*uint64(stat.Bsize) == 0 {
+		return fmt.Errorf("no blocks available")
+	}
+	freeDiskSpace := float64(stat.Bfree) / float64(stat.Blocks)
+	if freeDiskSpace < 0.10 {
+		return fmt.Errorf("not enough disk free disk space: %f", freeDiskSpace)
+	}
+
+	return nil
+}

pkg/wireguard/packetlogger_test.go

@@ -74,19 +74,70 @@ func TestParsePacket(t *testing.T) {
 	}
 }
 
+func TestParsePacketSNI(t *testing.T) {
+	storage := &testingmocks.MockMemoryStorage{}
+	clientCache := &ClientCache{
+		Addresses: []ClientCacheAddresses{
+			{
+				Address: net.IPNet{
+					IP:   net.ParseIP("10.189.184.2"),
+					Mask: net.IPMask(net.ParseIP("255.255.255.255").To4()),
+				},
+				ClientID: "1-2-3-4-1",
+			},
+			{
+				Address: net.IPNet{
+					IP:   net.ParseIP("10.189.184.3"),
+					Mask: net.IPMask(net.ParseIP("255.255.255.255").To4()),
+				},
+				ClientID: "1-2-3-5-1",
+			},
+		},
+	}
+	input := []string{
+		`450000d100004000400682160abdb80240e9b468ec5001bb4f71ed891a93673d8018080468f400000101080a1329f7772c5410131603010098010000940301f1d62f57f05cc00fc8fb984e7fc381a26adc301ec143b9bab6d36f3f1b15c97200002ec014c00a0039ff850088008100350084c013c00900330045002f0041c011c00700050004c012c0080016000a00ff0100003d00000013001100000e7777772e676f6f676c652e636f6d000b00020100000a000a0008001d0017001800190010000e000c02683208687474702f312e31`,
+	}
+	now := time.Now()
+	for _, s := range input {
+
+		data, err := hex.DecodeString(s)
+		if err != nil {
+			t.Fatalf("hex decode error: %s", err)
+		}
+		err = parsePacket(storage, data, clientCache)
+		if err != nil {
+			t.Fatalf("parse error: %s", err)
+		}
+	}
+
+	out, err := storage.ReadFile(path.Join(VPN_STATS_DIR, "ip-"+now.Format("2006-01-02.log")))
+	if err != nil {
+		t.Fatalf("read file error: %s", err)
+	}
+	if !strings.Contains(string(out), `,https,10.189.184.2,64.233.180.104,60496,443,www.google.com`) {
+		t.Fatalf("unexpected output. Expected https record")
+	}
+}
+
 func TestParseTLSExtensionSNI(t *testing.T) {
 	input := []string{
+		"00000013001100000e7777772e676f6f676c652e636f6d000b00020100000a000a0008001d0017001800190010000e000c02683208687474702f312e31",
 		"00000018001600001376706e2d7365727665722e696e3469742e696f",
 		"00000018001600001376706e2d7365727665722e696e3469742e696f000b00020100000a000a0008001d001700180019000d00180016080606010603080505010503080404010403020102030010000e000c02683208687474702f312e31",
 	}
-	for _, s := range input {
+	match := []string{
+		"www.google.com",
+		"vpn-server.in4it.io",
+		"vpn-server.in4it.io",
+	}
+	for k, s := range input {
 
 		data, err := hex.DecodeString(s)
 		if err != nil {
 			t.Fatalf("hex decode error: %s", err)
 		}
 		if sni := parseTLSExtensionSNI(data); sni != nil {
-			if string(sni) != "vpn-server.in4it.io" {
+			if string(sni) != match[k] {
 				t.Fatalf("got SNI, but expected different hostname. Got: %s", sni)
 			}
 		} else {
@@ -111,3 +162,10 @@ func TestParseTLSExtensionSNINoMatch(t *testing.T) {
 		}
 	}
 }
+
+func TestCheckDiskSpace(t *testing.T) {
+	err := checkDiskSpace()
+	if err != nil {
+		t.Fatalf("disk space error: %s", err)
+	}
+}