support ebpf

component/ebpf/tc/bpf_bpfeb.go

@@ -0,0 +1,119 @@
+// Code generated by bpf2go; DO NOT EDIT.
+//go:build arm64be || armbe || mips || mips64 || mips64p32 || ppc64 || s390 || s390x || sparc || sparc64
+// +build arm64be armbe mips mips64 mips64p32 ppc64 s390 s390x sparc sparc64
+
+package tc
+
+import (
+	"bytes"
+	_ "embed"
+	"fmt"
+	"io"
+
+	"github.com/cilium/ebpf"
+)
+
+// loadBpf returns the embedded CollectionSpec for bpf.
+func loadBpf() (*ebpf.CollectionSpec, error) {
+	reader := bytes.NewReader(_BpfBytes)
+	spec, err := ebpf.LoadCollectionSpecFromReader(reader)
+	if err != nil {
+		return nil, fmt.Errorf("can't load bpf: %w", err)
+	}
+
+	return spec, err
+}
+
+// loadBpfObjects loads bpf and converts it into a struct.
+//
+// The following types are suitable as obj argument:
+//
+//     *bpfObjects
+//     *bpfPrograms
+//     *bpfMaps
+//
+// See ebpf.CollectionSpec.LoadAndAssign documentation for details.
+func loadBpfObjects(obj interface{}, opts *ebpf.CollectionOptions) error {
+	spec, err := loadBpf()
+	if err != nil {
+		return err
+	}
+
+	return spec.LoadAndAssign(obj, opts)
+}
+
+// bpfSpecs contains maps and programs before they are loaded into the kernel.
+//
+// It can be passed ebpf.CollectionSpec.Assign.
+type bpfSpecs struct {
+	bpfProgramSpecs
+	bpfMapSpecs
+}
+
+// bpfSpecs contains programs before they are loaded into the kernel.
+//
+// It can be passed ebpf.CollectionSpec.Assign.
+type bpfProgramSpecs struct {
+	TcTunFunc *ebpf.ProgramSpec `ebpf:"tc_tun_func"`
+}
+
+// bpfMapSpecs contains maps before they are loaded into the kernel.
+//
+// It can be passed ebpf.CollectionSpec.Assign.
+type bpfMapSpecs struct {
+	TcParamsMap *ebpf.MapSpec `ebpf:"tc_params_map"`
+}
+
+// bpfObjects contains all objects after they have been loaded into the kernel.
+//
+// It can be passed to loadBpfObjects or ebpf.CollectionSpec.LoadAndAssign.
+type bpfObjects struct {
+	bpfPrograms
+	bpfMaps
+}
+
+func (o *bpfObjects) Close() error {
+	return _BpfClose(
+		&o.bpfPrograms,
+		&o.bpfMaps,
+	)
+}
+
+// bpfMaps contains all maps after they have been loaded into the kernel.
+//
+// It can be passed to loadBpfObjects or ebpf.CollectionSpec.LoadAndAssign.
+type bpfMaps struct {
+	TcParamsMap *ebpf.Map `ebpf:"tc_params_map"`
+}
+
+func (m *bpfMaps) Close() error {
+	return _BpfClose(
+		m.TcParamsMap,
+	)
+}
+
+// bpfPrograms contains all programs after they have been loaded into the kernel.
+//
+// It can be passed to loadBpfObjects or ebpf.CollectionSpec.LoadAndAssign.
+type bpfPrograms struct {
+	TcTunFunc *ebpf.Program `ebpf:"tc_tun_func"`
+}
+
+func (p *bpfPrograms) Close() error {
+	return _BpfClose(
+		p.TcTunFunc,
+	)
+}
+
+func _BpfClose(closers ...io.Closer) error {
+	for _, closer := range closers {
+		if err := closer.Close(); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+// Do not access this directly.
+//go:embed bpf_bpfeb.o
+var _BpfBytes []byte

component/ebpf/tc/bpf_bpfel.go

@@ -0,0 +1,119 @@
+// Code generated by bpf2go; DO NOT EDIT.
+//go:build 386 || amd64 || amd64p32 || arm || arm64 || mips64le || mips64p32le || mipsle || ppc64le || riscv64
+// +build 386 amd64 amd64p32 arm arm64 mips64le mips64p32le mipsle ppc64le riscv64
+
+package tc
+
+import (
+	"bytes"
+	_ "embed"
+	"fmt"
+	"io"
+
+	"github.com/cilium/ebpf"
+)
+
+// loadBpf returns the embedded CollectionSpec for bpf.
+func loadBpf() (*ebpf.CollectionSpec, error) {
+	reader := bytes.NewReader(_BpfBytes)
+	spec, err := ebpf.LoadCollectionSpecFromReader(reader)
+	if err != nil {
+		return nil, fmt.Errorf("can't load bpf: %w", err)
+	}
+
+	return spec, err
+}
+
+// loadBpfObjects loads bpf and converts it into a struct.
+//
+// The following types are suitable as obj argument:
+//
+//     *bpfObjects
+//     *bpfPrograms
+//     *bpfMaps
+//
+// See ebpf.CollectionSpec.LoadAndAssign documentation for details.
+func loadBpfObjects(obj interface{}, opts *ebpf.CollectionOptions) error {
+	spec, err := loadBpf()
+	if err != nil {
+		return err
+	}
+
+	return spec.LoadAndAssign(obj, opts)
+}
+
+// bpfSpecs contains maps and programs before they are loaded into the kernel.
+//
+// It can be passed ebpf.CollectionSpec.Assign.
+type bpfSpecs struct {
+	bpfProgramSpecs
+	bpfMapSpecs
+}
+
+// bpfSpecs contains programs before they are loaded into the kernel.
+//
+// It can be passed ebpf.CollectionSpec.Assign.
+type bpfProgramSpecs struct {
+	TcTunFunc *ebpf.ProgramSpec `ebpf:"tc_tun_func"`
+}
+
+// bpfMapSpecs contains maps before they are loaded into the kernel.
+//
+// It can be passed ebpf.CollectionSpec.Assign.
+type bpfMapSpecs struct {
+	TcParamsMap *ebpf.MapSpec `ebpf:"tc_params_map"`
+}
+
+// bpfObjects contains all objects after they have been loaded into the kernel.
+//
+// It can be passed to loadBpfObjects or ebpf.CollectionSpec.LoadAndAssign.
+type bpfObjects struct {
+	bpfPrograms
+	bpfMaps
+}
+
+func (o *bpfObjects) Close() error {
+	return _BpfClose(
+		&o.bpfPrograms,
+		&o.bpfMaps,
+	)
+}
+
+// bpfMaps contains all maps after they have been loaded into the kernel.
+//
+// It can be passed to loadBpfObjects or ebpf.CollectionSpec.LoadAndAssign.
+type bpfMaps struct {
+	TcParamsMap *ebpf.Map `ebpf:"tc_params_map"`
+}
+
+func (m *bpfMaps) Close() error {
+	return _BpfClose(
+		m.TcParamsMap,
+	)
+}
+
+// bpfPrograms contains all programs after they have been loaded into the kernel.
+//
+// It can be passed to loadBpfObjects or ebpf.CollectionSpec.LoadAndAssign.
+type bpfPrograms struct {
+	TcTunFunc *ebpf.Program `ebpf:"tc_tun_func"`
+}
+
+func (p *bpfPrograms) Close() error {
+	return _BpfClose(
+		p.TcTunFunc,
+	)
+}
+
+func _BpfClose(closers ...io.Closer) error {
+	for _, closer := range closers {
+		if err := closer.Close(); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+// Do not access this directly.
+//go:embed bpf_bpfel.o
+var _BpfBytes []byte

component/ebpf/tc/redirect_to_tun.go

@@ -0,0 +1,147 @@
+//go:build linux
+
+package tc
+
+import (
+	"fmt"
+	"io"
+	"net/netip"
+	"os"
+	"path/filepath"
+
+	"github.com/cilium/ebpf"
+	"github.com/cilium/ebpf/rlimit"
+	"github.com/vishvananda/netlink"
+	"golang.org/x/sys/unix"
+
+	C "github.com/Dreamacro/clash/constant"
+	"github.com/Dreamacro/clash/transport/socks5"
+)
+
+//go:generate go run github.com/cilium/ebpf/cmd/bpf2go -cc $BPF_CLANG -cflags $BPF_CFLAGS bpf ../bpf/tc.c
+
+const (
+	mapKey1 uint32 = 0
+	mapKey2 uint32 = 1
+)
+
+type EBpfTC struct {
+	objs   io.Closer
+	qdisc  netlink.Qdisc
+	filter netlink.Filter
+
+	ifName     string
+	ifIndex    int
+	ifMark     uint32
+	tunIfIndex uint32
+
+	bpfPath string
+}
+
+func NewEBpfTc(ifName string, ifIndex int, ifMark uint32, tunIfIndex uint32) *EBpfTC {
+	return &EBpfTC{
+		ifName:     ifName,
+		ifIndex:    ifIndex,
+		ifMark:     ifMark,
+		tunIfIndex: tunIfIndex,
+	}
+}
+
+func (e *EBpfTC) Start() error {
+	if err := rlimit.RemoveMemlock(); err != nil {
+		return fmt.Errorf("remove memory lock: %w", err)
+	}
+
+	e.bpfPath = filepath.Join(C.BpfFSPath, e.ifName)
+	if err := os.MkdirAll(e.bpfPath, os.ModePerm); err != nil {
+		return fmt.Errorf("failed to create bpf fs subpath: %w", err)
+	}
+
+	var objs bpfObjects
+	if err := loadBpfObjects(&objs, &ebpf.CollectionOptions{
+		Maps: ebpf.MapOptions{
+			PinPath: e.bpfPath,
+		},
+	}); err != nil {
+		e.Close()
+		return fmt.Errorf("loading objects: %w", err)
+	}
+
+	e.objs = &objs
+
+	if err := objs.bpfMaps.TcParamsMap.Update(mapKey1, e.ifMark, ebpf.UpdateAny); err != nil {
+		e.Close()
+		return fmt.Errorf("storing objects: %w", err)
+	}
+
+	if err := objs.bpfMaps.TcParamsMap.Update(mapKey2, e.tunIfIndex, ebpf.UpdateAny); err != nil {
+		e.Close()
+		return fmt.Errorf("storing objects: %w", err)
+	}
+
+	attrs := netlink.QdiscAttrs{
+		LinkIndex: e.ifIndex,
+		Handle:    netlink.MakeHandle(0xffff, 0),
+		Parent:    netlink.HANDLE_CLSACT,
+	}
+
+	qdisc := &netlink.GenericQdisc{
+		QdiscAttrs: attrs,
+		QdiscType:  "clsact",
+	}
+
+	e.qdisc = qdisc
+
+	if err := netlink.QdiscAdd(qdisc); err != nil {
+		if os.IsExist(err) {
+			_ = netlink.QdiscDel(qdisc)
+			err = netlink.QdiscAdd(qdisc)
+		}
+
+		if err != nil {
+			e.Close()
+			return fmt.Errorf("cannot add clsact qdisc: %w", err)
+		}
+	}
+
+	filterAttrs := netlink.FilterAttrs{
+		LinkIndex: e.ifIndex,
+		Parent:    netlink.HANDLE_MIN_EGRESS,
+		Handle:    netlink.MakeHandle(0, 1),
+		Protocol:  unix.ETH_P_ALL,
+		Priority:  1,
+	}
+
+	filter := &netlink.BpfFilter{
+		FilterAttrs:  filterAttrs,
+		Fd:           objs.bpfPrograms.TcTunFunc.FD(),
+		Name:         "clash-tc-" + e.ifName,
+		DirectAction: true,
+	}
+
+	if err := netlink.FilterAdd(filter); err != nil {
+		e.Close()
+		return fmt.Errorf("cannot attach ebpf object to filter: %w", err)
+	}
+
+	e.filter = filter
+
+	return nil
+}
+
+func (e *EBpfTC) Close() {
+	if e.filter != nil {
+		_ = netlink.FilterDel(e.filter)
+	}
+	if e.qdisc != nil {
+		_ = netlink.QdiscDel(e.qdisc)
+	}
+	if e.objs != nil {
+		_ = e.objs.Close()
+	}
+	_ = os.Remove(filepath.Join(e.bpfPath, "tc_params_map"))
+}
+
+func (e *EBpfTC) Lookup(_ netip.AddrPort) (socks5.Addr, error) {
+	return nil, fmt.Errorf("not supported")
+}