diff --git a/service/firewall/interception/windowskext2/handler.go b/service/firewall/interception/windowskext2/handler.go
index bb6348dd..166ebbc2 100644
--- a/service/firewall/interception/windowskext2/handler.go
+++ b/service/firewall/interception/windowskext2/handler.go
@@ -5,11 +5,13 @@ package windowskext
import (
"context"
+ "errors"
"fmt"
"net"
"time"
"github.com/safing/portmaster/service/process"
+ "github.com/safing/portmaster/windows_kext/kextinterface"
"github.com/tevino/abool"
@@ -32,8 +34,15 @@ func (v *VersionInfo) String() string {
func Handler(ctx context.Context, packets chan packet.Packet, bandwidthUpdate chan *packet.BandwidthUpdate) {
for {
packetInfo, err := RecvVerdictRequest()
+
+ if errors.Is(err, kextinterface.ErrUnexpectedInfoSize) || errors.Is(err, kextinterface.ErrUnexpectedReadError) {
+ log.Criticalf("unexpected kext info data: %s", err)
+ continue // Depending on the info type this may not affect the functionality. Try to continue reading the next commands.
+ }
+
if err != nil {
log.Warningf("failed to get packet from windows kext: %s", err)
+ // Probably IO error, nothing else we can do.
return
}
diff --git a/windows_kext/kextinterface/info.go b/windows_kext/kextinterface/info.go
index 763c3e8e..a2f5cd91 100644
--- a/windows_kext/kextinterface/info.go
+++ b/windows_kext/kextinterface/info.go
@@ -3,6 +3,7 @@ package kextinterface
import (
"encoding/binary"
"errors"
+ "fmt"
"io"
)
@@ -18,6 +19,7 @@ const (
var (
ErrUnknownInfoType = errors.New("unknown info type")
+ ErrUnexpectedInfoSize = errors.New("unexpected info size")
ErrUnexpectedReadError = errors.New("unexpected read error")
)
@@ -135,117 +137,215 @@ type Info struct {
BandwidthStats *BandwidthStatsArray
}
-func RecvInfo(reader io.Reader) (*Info, error) {
- var infoType byte
- err := binary.Read(reader, binary.LittleEndian, &infoType)
+type readHelper struct {
+ infoType byte
+ commandSize uint32
+
+ readSize int
+
+ reader io.Reader
+}
+
+func newReadHelper(reader io.Reader) (*readHelper, error) {
+ helper := &readHelper{reader: reader}
+
+ err := binary.Read(reader, binary.LittleEndian, &helper.infoType)
if err != nil {
return nil, err
}
- // Read size of data
- var size uint32
- err = binary.Read(reader, binary.LittleEndian, &size)
+ err = binary.Read(reader, binary.LittleEndian, &helper.commandSize)
if err != nil {
return nil, err
}
+ return helper, nil
+}
+
+func (r *readHelper) ReadData(data any) error {
+ err := binary.Read(r, binary.LittleEndian, data)
+ if err != nil {
+ return errors.Join(ErrUnexpectedReadError, err)
+ }
+
+ if err := r.checkOverRead(); err != nil {
+ return err
+ }
+
+ return nil
+}
+
+// Passing size = 0 will read the rest of the command.
+func (r *readHelper) ReadBytes(size uint32) ([]byte, error) {
+ if uint32(r.readSize) >= r.commandSize {
+ return nil, errors.Join(fmt.Errorf("cannot read more bytes than the command size: %d >= %d", r.readSize, r.commandSize), ErrUnexpectedReadError)
+ }
+
+ if size == 0 {
+ size = r.commandSize - uint32(r.readSize)
+ }
+
+ if r.commandSize < uint32(r.readSize)+size {
+ return nil, ErrUnexpectedInfoSize
+ }
+
+ bytes := make([]byte, size)
+ err := binary.Read(r, binary.LittleEndian, bytes)
+ if err != nil {
+ return nil, errors.Join(ErrUnexpectedReadError, err)
+ }
+
+ return bytes, nil
+}
+
+func (r *readHelper) ReadUntilTheEnd() {
+ _, _ = r.ReadBytes(0)
+}
+
+func (r *readHelper) checkOverRead() error {
+ if uint32(r.readSize) > r.commandSize {
+ return ErrUnexpectedInfoSize
+ }
+
+ return nil
+}
+
+func (r *readHelper) Read(p []byte) (n int, err error) {
+ n, err = r.reader.Read(p)
+ r.readSize += n
+ return
+}
+
+func RecvInfo(reader io.Reader) (*Info, error) {
+ helper, err := newReadHelper(reader)
+ if err != nil {
+ return nil, err
+ }
+
+ // Make sure the whole command is read before return.
+ defer helper.ReadUntilTheEnd()
+
// Read data
- switch infoType {
+ switch helper.infoType {
case InfoConnectionIpv4:
{
+ parseError := fmt.Errorf("failed to parse InfoConnectionIpv4")
+ newInfo := ConnectionV4{}
var fixedSizeValues connectionV4Internal
- err = binary.Read(reader, binary.LittleEndian, &fixedSizeValues)
+ // Read fixed size values.
+ err = helper.ReadData(&fixedSizeValues)
if err != nil {
- return nil, errors.Join(ErrUnexpectedReadError, err)
+ return nil, errors.Join(parseError, err, fmt.Errorf("fixed"))
}
- // Read size of payload
- var size uint32
- err = binary.Read(reader, binary.LittleEndian, &size)
+ newInfo.connectionV4Internal = fixedSizeValues
+ // Read size of payload.
+ var payloadSize uint32
+ err = helper.ReadData(&payloadSize)
if err != nil {
- return nil, errors.Join(ErrUnexpectedReadError, err)
+ return nil, errors.Join(parseError, err, fmt.Errorf("payloadsize"))
}
- newInfo := ConnectionV4{connectionV4Internal: fixedSizeValues, Payload: make([]byte, size)}
- err = binary.Read(reader, binary.LittleEndian, &newInfo.Payload)
- if err != nil {
- return nil, errors.Join(ErrUnexpectedReadError, err)
+
+ // Check if there is payload.
+ if payloadSize > 0 {
+ // Read payload.
+ newInfo.Payload, err = helper.ReadBytes(payloadSize)
+ if err != nil {
+ return nil, errors.Join(parseError, err, fmt.Errorf("payload"))
+ }
}
return &Info{ConnectionV4: &newInfo}, nil
}
case InfoConnectionIpv6:
{
- var fixedSizeValues connectionV6Internal
- err = binary.Read(reader, binary.LittleEndian, &fixedSizeValues)
+ parseError := fmt.Errorf("failed to parse InfoConnectionIpv6")
+ newInfo := ConnectionV6{}
+
+ // Read fixed size values.
+ err = helper.ReadData(&newInfo.connectionV6Internal)
if err != nil {
- return nil, errors.Join(ErrUnexpectedReadError, err)
+ return nil, errors.Join(parseError, err)
}
- // Read size of payload
- var size uint32
- err = binary.Read(reader, binary.LittleEndian, &size)
+
+ // Read size of payload.
+ var payloadSize uint32
+ err = helper.ReadData(&payloadSize)
if err != nil {
- return nil, errors.Join(ErrUnexpectedReadError, err)
+ return nil, errors.Join(parseError, err)
}
- newInfo := ConnectionV6{connectionV6Internal: fixedSizeValues, Payload: make([]byte, size)}
- err = binary.Read(reader, binary.LittleEndian, &newInfo.Payload)
- if err != nil {
- return nil, errors.Join(ErrUnexpectedReadError, err)
+
+ // Check if there is payload.
+ if payloadSize > 0 {
+ // Read payload.
+ newInfo.Payload, err = helper.ReadBytes(payloadSize)
+ if err != nil {
+ return nil, errors.Join(parseError, err)
+ }
}
+
return &Info{ConnectionV6: &newInfo}, nil
}
case InfoConnectionEndEventV4:
{
+ parseError := fmt.Errorf("failed to parse InfoConnectionEndEventV4")
var connectionEnd ConnectionEndV4
- err = binary.Read(reader, binary.LittleEndian, &connectionEnd)
+
+ // Read fixed size values.
+ err = helper.ReadData(&connectionEnd)
if err != nil {
- return nil, errors.Join(ErrUnexpectedReadError, err)
+ return nil, errors.Join(parseError, err)
}
return &Info{ConnectionEndV4: &connectionEnd}, nil
}
case InfoConnectionEndEventV6:
{
+ parseError := fmt.Errorf("failed to parse InfoConnectionEndEventV6")
var connectionEnd ConnectionEndV6
- err = binary.Read(reader, binary.LittleEndian, &connectionEnd)
+
+ // Read fixed size values.
+ err = helper.ReadData(&connectionEnd)
if err != nil {
- return nil, errors.Join(ErrUnexpectedReadError, err)
+ return nil, errors.Join(parseError, err)
}
return &Info{ConnectionEndV6: &connectionEnd}, nil
}
case InfoLogLine:
{
+ parseError := fmt.Errorf("failed to parse InfoLogLine")
logLine := LogLine{}
// Read severity
- err = binary.Read(reader, binary.LittleEndian, &logLine.Severity)
+ err = helper.ReadData(&logLine.Severity)
if err != nil {
- return nil, errors.Join(ErrUnexpectedReadError, err)
+ return nil, errors.Join(parseError, err)
}
// Read string
- line := make([]byte, size-1) // -1 for the severity enum.
- err = binary.Read(reader, binary.LittleEndian, &line)
+ bytes, err := helper.ReadBytes(0)
if err != nil {
- return nil, errors.Join(ErrUnexpectedReadError, err)
+ return nil, errors.Join(parseError, err)
}
- logLine.Line = string(line)
+ logLine.Line = string(bytes)
return &Info{LogLine: &logLine}, nil
}
case InfoBandwidthStatsV4:
{
+ parseError := fmt.Errorf("failed to parse InfoBandwidthStatsV4")
// Read Protocol
var protocol uint8
- err = binary.Read(reader, binary.LittleEndian, &protocol)
+ err = helper.ReadData(&protocol)
if err != nil {
- return nil, errors.Join(ErrUnexpectedReadError, err)
+ return nil, errors.Join(parseError, err)
}
// Read size of array
var size uint32
- err = binary.Read(reader, binary.LittleEndian, &size)
+ err = helper.ReadData(&size)
if err != nil {
- return nil, errors.Join(ErrUnexpectedReadError, err)
+ return nil, errors.Join(parseError, err)
}
// Read array
statsArray := make([]BandwidthValueV4, size)
for i := range int(size) {
- err = binary.Read(reader, binary.LittleEndian, &statsArray[i])
+ err = helper.ReadData(&statsArray[i])
if err != nil {
- return nil, errors.Join(ErrUnexpectedReadError, err)
+ return nil, errors.Join(parseError, err)
}
}
@@ -253,24 +353,25 @@ func RecvInfo(reader io.Reader) (*Info, error) {
}
case InfoBandwidthStatsV6:
{
+ parseError := fmt.Errorf("failed to parse InfoBandwidthStatsV6")
// Read Protocol
var protocol uint8
- err = binary.Read(reader, binary.LittleEndian, &protocol)
+ err = helper.ReadData(&protocol)
if err != nil {
- return nil, errors.Join(ErrUnexpectedReadError, err)
+ return nil, errors.Join(parseError, err)
}
// Read size of array
var size uint32
- err = binary.Read(reader, binary.LittleEndian, &size)
+ err = helper.ReadData(&size)
if err != nil {
- return nil, errors.Join(ErrUnexpectedReadError, err)
+ return nil, errors.Join(parseError, err)
}
// Read array
statsArray := make([]BandwidthValueV6, size)
for i := range int(size) {
- err = binary.Read(reader, binary.LittleEndian, &statsArray[i])
+ err = helper.ReadData(&statsArray[i])
if err != nil {
- return nil, errors.Join(ErrUnexpectedReadError, err)
+ return nil, errors.Join(parseError, err)
}
}
@@ -278,10 +379,5 @@ func RecvInfo(reader io.Reader) (*Info, error) {
}
}
- // Command not recognized, read until the end of command and return.
- // During normal operation this should not happen.
- unknownData := make([]byte, size)
- _, _ = reader.Read(unknownData)
-
return nil, ErrUnknownInfoType
}
diff --git a/windows_kext/kextinterface/protocol_test.go b/windows_kext/kextinterface/protocol_test.go
index cf047442..c09cf286 100644
--- a/windows_kext/kextinterface/protocol_test.go
+++ b/windows_kext/kextinterface/protocol_test.go
@@ -18,8 +18,17 @@ func TestRustInfoFile(t *testing.T) {
defer func() {
_ = file.Close()
}()
+ first := true
for {
info, err := RecvInfo(file)
+ // First info should be with invalid size.
+ if first {
+ if !errors.Is(err, ErrUnexpectedInfoSize) {
+ t.Errorf("unexpected error: %s\n", err)
+ }
+ first = false
+ continue
+ }
if err != nil {
if errors.Is(err, ErrUnexpectedReadError) {
t.Errorf("unexpected error: %s\n", err)
diff --git a/windows_kext/kextinterface/testdata/rust_info_test.bin b/windows_kext/kextinterface/testdata/rust_info_test.bin
index 3f9049a9..3b8588c7 100644
Binary files a/windows_kext/kextinterface/testdata/rust_info_test.bin and b/windows_kext/kextinterface/testdata/rust_info_test.bin differ
diff --git a/windows_kext/protocol/src/info.rs b/windows_kext/protocol/src/info.rs
index b8eb0c79..fc50d589 100644
--- a/windows_kext/protocol/src/info.rs
+++ b/windows_kext/protocol/src/info.rs
@@ -441,6 +441,22 @@ fn generate_test_info_file() -> Result<(), std::io::Error> {
for _ in 0..selected.capacity() {
selected.push(enums.choose(&mut rng).unwrap().clone());
}
+ // Write wrong size data.
+ let mut info = connection_info_v6(
+ 1,
+ 2,
+ 3,
+ 4,
+ [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16],
+ [2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17],
+ 5,
+ 6,
+ 7,
+ &[1, 2, 3, 4, 5, 6, 7, 8, 9, 10],
+ );
+ info.assert_size();
+ info.0[0] = InfoType::ConnectionIpv4 as u8;
+ file.write_all(&info.0)?;
for value in selected {
file.write_all(&match value {
@@ -548,5 +564,6 @@ fn generate_test_info_file() -> Result<(), std::io::Error> {
}
})?;
}
+
return Ok(());
}
diff --git a/windows_kext/protocol/testdata/go_command_test.bin b/windows_kext/protocol/testdata/go_command_test.bin
index 586c70ad..d518dbf1 100644
Binary files a/windows_kext/protocol/testdata/go_command_test.bin and b/windows_kext/protocol/testdata/go_command_test.bin differ