Refactor: linux process resolving (#2305)

component/process/process_linux.go

@@ -6,31 +6,57 @@ import (
 	"fmt"
 	"net"
 	"os"
-	"path"
+	"path/filepath"
 	"strings"
 	"syscall"
 	"unicode"
 	"unsafe"
 
-	"github.com/Dreamacro/clash/common/pool"
+	"github.com/mdlayher/netlink"
+	"golang.org/x/sys/unix"
 )
 
-// from https://github.com/vishvananda/netlink/blob/bca67dfc8220b44ef582c9da4e9172bf1c9ec973/nl/nl_linux.go#L52-L62
-var nativeEndian = func() binary.ByteOrder {
-	var x uint32 = 0x01020304
-	if *(*byte)(unsafe.Pointer(&x)) == 0x01 {
-		return binary.BigEndian
-	}
-
-	return binary.LittleEndian
-}()
-
 const (
-	sizeOfSocketDiagRequest = syscall.SizeofNlMsghdr + 8 + 48
+	SOCK_DIAG_BY_FAMILY  = 20
-	socketDiagByFamily      = 20
+	inetDiagRequestSize  = int(unsafe.Sizeof(inetDiagRequest{}))
-	pathProc                = "/proc"
+	inetDiagResponseSize = int(unsafe.Sizeof(inetDiagResponse{}))
 )
 
+type inetDiagRequest struct {
+	Family   byte
+	Protocol byte
+	Ext      byte
+	Pad      byte
+	States   uint32
+
+	SrcPort [2]byte
+	DstPort [2]byte
+	Src     [16]byte
+	Dst     [16]byte
+	If      uint32
+	Cookie  [2]uint32
+}
+
+type inetDiagResponse struct {
+	Family  byte
+	State   byte
+	Timer   byte
+	ReTrans byte
+
+	SrcPort [2]byte
+	DstPort [2]byte
+	Src     [16]byte
+	Dst     [16]byte
+	If      uint32
+	Cookie  [2]uint32
+
+	Expires uint32
+	RQueue  uint32
+	WQueue  uint32
+	UID     uint32
+	INode   uint32
+}
+
 func findProcessName(network string, ip net.IP, srcPort int) (string, error) {
 	inode, uid, err := resolveSocketByNetlink(network, ip, srcPort)
 	if err != nil {
@@ -40,132 +66,73 @@ func findProcessName(network string, ip net.IP, srcPort int) (string, error) {
 	return resolveProcessNameByProcSearch(inode, uid)
 }
 
-func resolveSocketByNetlink(network string, ip net.IP, srcPort int) (int32, int32, error) {
+func resolveSocketByNetlink(network string, ip net.IP, srcPort int) (uint32, uint32, error) {
-	var family byte
+	request := &inetDiagRequest{
-	var protocol byte
+		States: 0xffffffff,
-
+		Cookie: [2]uint32{0xffffffff, 0xffffffff},
-	switch network {
-	case TCP:
-		protocol = syscall.IPPROTO_TCP
-	case UDP:
-		protocol = syscall.IPPROTO_UDP
-	default:
-		return 0, 0, ErrInvalidNetwork
 	}
 
 	if ip.To4() != nil {
-		family = syscall.AF_INET
+		request.Family = unix.AF_INET
 	} else {
-		family = syscall.AF_INET6
+		request.Family = unix.AF_INET6
 	}
 
-	req := packSocketDiagRequest(family, protocol, ip, uint16(srcPort))
+	if strings.HasPrefix(network, "tcp") {
+		request.Protocol = unix.IPPROTO_TCP
+	} else if strings.HasPrefix(network, "udp") {
+		request.Protocol = unix.IPPROTO_UDP
+	} else {
+		return 0, 0, ErrInvalidNetwork
+	}
 
-	socket, err := syscall.Socket(syscall.AF_NETLINK, syscall.SOCK_DGRAM, syscall.NETLINK_INET_DIAG)
+	if v4 := ip.To4(); v4 != nil {
+		copy(request.Src[:], v4)
+	} else {
+		copy(request.Src[:], ip)
+	}
+
+	binary.BigEndian.PutUint16(request.SrcPort[:], uint16(srcPort))
+
+	conn, err := netlink.Dial(unix.NETLINK_INET_DIAG, nil)
 	if err != nil {
-		return 0, 0, fmt.Errorf("dial netlink: %w", err)
+		return 0, 0, err
 	}
-	defer syscall.Close(socket)
+	defer conn.Close()
 
-	syscall.SetsockoptTimeval(socket, syscall.SOL_SOCKET, syscall.SO_SNDTIMEO, &syscall.Timeval{Usec: 100})
+	message := netlink.Message{
-	syscall.SetsockoptTimeval(socket, syscall.SOL_SOCKET, syscall.SO_RCVTIMEO, &syscall.Timeval{Usec: 100})
+		Header: netlink.Header{
+			Type:  SOCK_DIAG_BY_FAMILY,
+			Flags: netlink.Request | netlink.Dump,
+		},
+		Data: (*(*[inetDiagRequestSize]byte)(unsafe.Pointer(request)))[:],
+	}
 
-	if err := syscall.Connect(socket, &syscall.SockaddrNetlink{
+	messages, err := conn.Execute(message)
-		Family: syscall.AF_NETLINK,
+	if err != nil {
-		Pad:    0,
-		Pid:    0,
-		Groups: 0,
-	}); err != nil {
 		return 0, 0, err
 	}
 
-	if _, err := syscall.Write(socket, req); err != nil {
+	for _, msg := range messages {
-		return 0, 0, fmt.Errorf("write request: %w", err)
+		if len(msg.Data) < inetDiagResponseSize {
+			continue
 		}
 
-	rb := pool.Get(pool.RelayBufferSize)
+		response := (*inetDiagResponse)(unsafe.Pointer(&msg.Data[0]))
-	defer pool.Put(rb)
 
-	n, err := syscall.Read(socket, rb)
+		return response.INode, response.UID, nil
-	if err != nil {
-		return 0, 0, fmt.Errorf("read response: %w", err)
 	}
 
-	messages, err := syscall.ParseNetlinkMessage(rb[:n])
+	return 0, 0, ErrNotFound
-	if err != nil {
-		return 0, 0, fmt.Errorf("parse netlink message: %w", err)
-	} else if len(messages) == 0 {
-		return 0, 0, fmt.Errorf("unexcepted netlink response")
-	}
-
-	message := messages[0]
-	if message.Header.Type&syscall.NLMSG_ERROR != 0 {
-		return 0, 0, fmt.Errorf("netlink message: NLMSG_ERROR")
-	}
-
-	inode, uid := unpackSocketDiagResponse(&messages[0])
-	if inode < 0 || uid < 0 {
-		return 0, 0, fmt.Errorf("invalid inode(%d) or uid(%d)", inode, uid)
-	}
-
-	return inode, uid, nil
 }
 
-func packSocketDiagRequest(family, protocol byte, source net.IP, sourcePort uint16) []byte {
+func resolveProcessNameByProcSearch(inode, uid uint32) (string, error) {
-	s := make([]byte, 16)
+	files, err := os.ReadDir("/proc")
-
-	if v4 := source.To4(); v4 != nil {
-		copy(s, v4)
-	} else {
-		copy(s, source)
-	}
-
-	buf := make([]byte, sizeOfSocketDiagRequest)
-
-	nativeEndian.PutUint32(buf[0:4], sizeOfSocketDiagRequest)
-	nativeEndian.PutUint16(buf[4:6], socketDiagByFamily)
-	nativeEndian.PutUint16(buf[6:8], syscall.NLM_F_REQUEST|syscall.NLM_F_DUMP)
-	nativeEndian.PutUint32(buf[8:12], 0)
-	nativeEndian.PutUint32(buf[12:16], 0)
-
-	buf[16] = family
-	buf[17] = protocol
-	buf[18] = 0
-	buf[19] = 0
-	nativeEndian.PutUint32(buf[20:24], 0xFFFFFFFF)
-
-	binary.BigEndian.PutUint16(buf[24:26], sourcePort)
-	binary.BigEndian.PutUint16(buf[26:28], 0)
-
-	copy(buf[28:44], s)
-	copy(buf[44:60], net.IPv6zero)
-
-	nativeEndian.PutUint32(buf[60:64], 0)
-	nativeEndian.PutUint64(buf[64:72], 0xFFFFFFFFFFFFFFFF)
-
-	return buf
-}
-
-func unpackSocketDiagResponse(msg *syscall.NetlinkMessage) (inode, uid int32) {
-	if len(msg.Data) < 72 {
-		return 0, 0
-	}
-
-	data := msg.Data
-
-	uid = int32(nativeEndian.Uint32(data[64:68]))
-	inode = int32(nativeEndian.Uint32(data[68:72]))
-
-	return
-}
-
-func resolveProcessNameByProcSearch(inode, uid int32) (string, error) {
-	files, err := os.ReadDir(pathProc)
 	if err != nil {
 		return "", err
 	}
 
-	buffer := make([]byte, syscall.PathMax)
+	buffer := make([]byte, unix.PathMax)
 	socket := fmt.Appendf(nil, "socket:[%d]", inode)
 
 	for _, f := range files {
@@ -177,12 +144,12 @@ func resolveProcessNameByProcSearch(inode, uid int32) (string, error) {
 		if err != nil {
 			return "", err
 		}
-		if info.Sys().(*syscall.Stat_t).Uid != uint32(uid) {
+		if info.Sys().(*syscall.Stat_t).Uid != uid {
 			continue
 		}
 
-		processPath := path.Join(pathProc, f.Name())
+		processPath := filepath.Join("/proc", f.Name())
-		fdPath := path.Join(processPath, "fd")
+		fdPath := filepath.Join(processPath, "fd")
 
 		fds, err := os.ReadDir(fdPath)
 		if err != nil {
@@ -190,13 +157,13 @@ func resolveProcessNameByProcSearch(inode, uid int32) (string, error) {
 		}
 
 		for _, fd := range fds {
-			n, err := syscall.Readlink(path.Join(fdPath, fd.Name()), buffer)
+			n, err := unix.Readlink(filepath.Join(fdPath, fd.Name()), buffer)
 			if err != nil {
 				continue
 			}
 
 			if bytes.Equal(buffer[:n], socket) {
-				return os.Readlink(path.Join(processPath, "exe"))
+				return os.Readlink(filepath.Join(processPath, "exe"))
 			}
 		}
 	}

go.mod

@@ -9,6 +9,7 @@ require (
 	github.com/gofrs/uuid v4.2.0+incompatible
 	github.com/gorilla/websocket v1.5.0
 	github.com/insomniacslk/dhcp v0.0.0-20220822114210-de18a9d48e84
+	github.com/mdlayher/netlink v1.6.0
 	github.com/miekg/dns v1.1.50
 	github.com/oschwald/geoip2-golang v1.8.0
 	github.com/sirupsen/logrus v1.9.0
@@ -26,7 +27,10 @@ require (
 require (
 	github.com/ajg/form v1.5.1 // indirect
 	github.com/davecgh/go-spew v1.1.1 // indirect
+	github.com/google/go-cmp v0.5.7 // indirect
+	github.com/josharian/native v1.0.0 // indirect
 	github.com/kr/text v0.2.0 // indirect
+	github.com/mdlayher/socket v0.1.1 // indirect
 	github.com/oschwald/maxminddb-golang v1.10.0 // indirect
 	github.com/pmezard/go-difflib v1.0.0 // indirect
 	github.com/u-root/uio v0.0.0-20210528114334-82958018845c // indirect

go.sum

@@ -18,12 +18,17 @@ github.com/google/go-cmp v0.3.0/go.mod h1:8QqcDgzrUqlUb/G2PQTWiueGozuR1884gddMyw
 github.com/google/go-cmp v0.3.1/go.mod h1:8QqcDgzrUqlUb/G2PQTWiueGozuR1884gddMywk6iLU=
 github.com/google/go-cmp v0.4.0/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
 github.com/google/go-cmp v0.5.2/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
+github.com/google/go-cmp v0.5.6/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
+github.com/google/go-cmp v0.5.7 h1:81/ik6ipDQS2aGcBfIN5dHDB36BwrStyeAQquSYCV4o=
+github.com/google/go-cmp v0.5.7/go.mod h1:n+brtR0CgQNWTVd5ZUFpTBC8YFBDLK/h/bpaJ8/DtOE=
 github.com/gopherjs/gopherjs v0.0.0-20181017120253-0766667cb4d1/go.mod h1:wJfORRmW1u3UXTncJ5qlYoELFm8eSnnEO6hX4iZ3EWY=
 github.com/gorilla/websocket v1.5.0 h1:PPwGk2jz7EePpoHN/+ClbZu8SPxiqlu12wZP/3sWmnc=
 github.com/gorilla/websocket v1.5.0/go.mod h1:YR8l580nyteQvAITg2hZ9XVh4b55+EU/adAjf1fMHhE=
 github.com/hugelgupf/socketpair v0.0.0-20190730060125-05d35a94e714/go.mod h1:2Goc3h8EklBH5mspfHFxBnEoURQCGzQQH1ga9Myjvis=
 github.com/insomniacslk/dhcp v0.0.0-20220822114210-de18a9d48e84 h1:MJTy6H+EpXLeAn0P5WAWeLk6dJA3V0ik6S3VJfUyQuI=
 github.com/insomniacslk/dhcp v0.0.0-20220822114210-de18a9d48e84/go.mod h1:h+MxyHxRg9NH3terB1nfRIUaQEcI0XOVkdR9LNBlp8E=
+github.com/josharian/native v1.0.0 h1:Ts/E8zCSEsG17dUqv7joXJFybuMLjQfWE04tsBODTxk=
+github.com/josharian/native v1.0.0/go.mod h1:7X/raswPFr05uY3HiLlYeyQntB6OO7E/d2Cu7qoaN2w=
 github.com/jsimonetti/rtnetlink v0.0.0-20190606172950-9527aa82566a/go.mod h1:Oz+70psSo5OFh8DBl0Zv2ACw7Esh6pPUphlvZG9x7uw=
 github.com/jsimonetti/rtnetlink v0.0.0-20200117123717-f846d4f6c1f4/go.mod h1:WGuG/smIU4J/54PblvSbh+xvCZmpJnFgr3ds6Z55XMQ=
 github.com/jsimonetti/rtnetlink v0.0.0-20201009170750-9c6f07d100c1/go.mod h1:hqoO/u39cqLeBLebZ8fWdE96O7FxrAsRYhnVOdgHxok=
@@ -37,8 +42,12 @@ github.com/mdlayher/netlink v0.0.0-20190409211403-11939a169225/go.mod h1:eQB3mZE
 github.com/mdlayher/netlink v1.0.0/go.mod h1:KxeJAFOFLG6AjpyDkQ/iIhxygIUKD+vcwqcnu43w/+M=
 github.com/mdlayher/netlink v1.1.0/go.mod h1:H4WCitaheIsdF9yOYu8CFmCgQthAPIWZmcKp9uZHgmY=
 github.com/mdlayher/netlink v1.1.1/go.mod h1:WTYpFb/WTvlRJAyKhZL5/uy69TDDpHHu2VZmb2XgV7o=
+github.com/mdlayher/netlink v1.6.0 h1:rOHX5yl7qnlpiVkFWoqccueppMtXzeziFjWAjLg6sz0=
+github.com/mdlayher/netlink v1.6.0/go.mod h1:0o3PlBmGst1xve7wQ7j/hwpNaFaH4qCRyWCdcZk8/vA=
 github.com/mdlayher/raw v0.0.0-20190606142536-fef19f00fc18/go.mod h1:7EpbotpCmVZcu+KCX4g9WaRNuu11uyhiW7+Le1dKawg=
 github.com/mdlayher/raw v0.0.0-20191009151244-50f2db8cc065/go.mod h1:7EpbotpCmVZcu+KCX4g9WaRNuu11uyhiW7+Le1dKawg=
+github.com/mdlayher/socket v0.1.1 h1:q3uOGirUPfAV2MUoaC7BavjQ154J7+JOkTWyiV+intI=
+github.com/mdlayher/socket v0.1.1/go.mod h1:mYV5YIZAfHh4dzDVzI8x8tWLWCliuX8Mon5Awbj+qDs=
 github.com/miekg/dns v1.1.50 h1:DQUfb9uc6smULcREF09Uc+/Gd46YWqJd5DbpPE9xkcA=
 github.com/miekg/dns v1.1.50/go.mod h1:e3IlAVfNqAllflbibAZEWOXOQ+Ynzk/dDozDxY7XnME=
 github.com/oschwald/geoip2-golang v1.8.0 h1:KfjYB8ojCEn/QLqsDU0AzrJ3R5Qa9vFlx3z6SLNcKTs=
@@ -87,6 +96,8 @@ golang.org/x/net v0.0.0-20201010224723-4f7140c49acb/go.mod h1:sp8m0HH+o8qH0wwXwY
 golang.org/x/net v0.0.0-20201110031124-69a78807bb2b/go.mod h1:sp8m0HH+o8qH0wwXwYZr8TS3Oi6o0r6Gce1SSxlDquU=
 golang.org/x/net v0.0.0-20210405180319-a5a99cb37ef4/go.mod h1:p54w0d4576C0XHj96bSt6lcn1PtDYWL6XObtHCRCNQM=
 golang.org/x/net v0.0.0-20210726213435-c6fcb2dbf985/go.mod h1:9nx3DQGgdP8bBQD5qxJ1jj9UTztislL4KSBs9R2vV5Y=
+golang.org/x/net v0.0.0-20210928044308-7d9f5e0b762b/go.mod h1:9nx3DQGgdP8bBQD5qxJ1jj9UTztislL4KSBs9R2vV5Y=
+golang.org/x/net v0.0.0-20220127200216-cd36cc0744dd/go.mod h1:CfG3xpIq0wQ8r1q4Su4UZFWDARRcnwPjda9FqA0JpMk=
 golang.org/x/net v0.0.0-20220822230855-b0a4917ee28c h1:JVAXQ10yGGVbSyoer5VILysz6YKjdNT2bsvlayjqhes=
 golang.org/x/net v0.0.0-20220822230855-b0a4917ee28c/go.mod h1:YDH+HFinaLZZlnHAfSS6ZXJJ9M9t4Dl22yv3iI2vPwk=
 golang.org/x/sync v0.0.0-20190423024810-112230192c58/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
@@ -111,11 +122,16 @@ golang.org/x/sys v0.0.0-20210330210617-4fbd30eecc44/go.mod h1:h1NjWce9XRLGQEsW7w
 golang.org/x/sys v0.0.0-20210423082822-04245dca01da/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20210510120138-977fb7262007/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.0.0-20210525143221-35b2ab0089ea/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.0.0-20210615035016-665e8c7367d1/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.0.0-20210630005230-0f9fa26af87c/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.0.0-20210927094055-39ccf1dd6fa6/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.0.0-20211216021012-1d35b9e2eb4e/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.0.0-20220128215802-99c3d69c2c27/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.0.0-20220715151400-c0bba94af5f8/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.0.0-20220825204002-c680a09ffe64 h1:UiNENfZ8gDvpiWw7IpOMQ27spWmThO1RwwdQVbJahJM=
 golang.org/x/sys v0.0.0-20220825204002-c680a09ffe64/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/term v0.0.0-20201126162022-7de9c90e9dd1/go.mod h1:bj7SfCRtBDWHUb9snDiAeCFNEtKQo2Wmx5Cou7ajbmo=
+golang.org/x/term v0.0.0-20210927222741-03fcf44c2211/go.mod h1:jbD1KX2456YbFQfuXm/mYQcufACuNUgVhRMnK/tPxf8=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 golang.org/x/text v0.3.3/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
 golang.org/x/text v0.3.6/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=