package netlink
import (
"errors"
"fmt"
"net"
"syscall"
"github.com/vishvananda/netlink/nl"
"golang.org/x/sys/unix"
)
const (
sizeofSocketID = 0x30
sizeofSocketRequest = sizeofSocketID + 0x8
sizeofSocket = sizeofSocketID + 0x18
sizeofUnixSocketRequest = 0x18 // 24 byte
sizeofUnixSocket = 0x10 // 16 byte
)
type socketRequest struct {
Family uint8
Protocol uint8
Ext uint8
pad uint8
States uint32
ID SocketID
}
type writeBuffer struct {
Bytes []byte
pos int
}
func (b *writeBuffer) Write(c byte) {
b.Bytes[b.pos] = c
b.pos++
}
func (b *writeBuffer) Next(n int) []byte {
s := b.Bytes[b.pos : b.pos+n]
b.pos += n
return s
}
func (r *socketRequest) Serialize() []byte {
b := writeBuffer{Bytes: make([]byte, sizeofSocketRequest)}
b.Write(r.Family)
b.Write(r.Protocol)
b.Write(r.Ext)
b.Write(r.pad)
native.PutUint32(b.Next(4), r.States)
networkOrder.PutUint16(b.Next(2), r.ID.SourcePort)
networkOrder.PutUint16(b.Next(2), r.ID.DestinationPort)
if r.Family == unix.AF_INET6 {
copy(b.Next(16), r.ID.Source)
copy(b.Next(16), r.ID.Destination)
} else {
copy(b.Next(16), r.ID.Source.To4())
copy(b.Next(16), r.ID.Destination.To4())
}
native.PutUint32(b.Next(4), r.ID.Interface)
native.PutUint32(b.Next(4), r.ID.Cookie[0])
native.PutUint32(b.Next(4), r.ID.Cookie[1])
return b.Bytes
}
func (r *socketRequest) Len() int { return sizeofSocketRequest }
// According to linux/include/uapi/linux/unix_diag.h
type unixSocketRequest struct {
Family uint8
Protocol uint8
pad uint16
States uint32
INode uint32
Show uint32
Cookie [2]uint32
}
func (r *unixSocketRequest) Serialize() []byte {
b := writeBuffer{Bytes: make([]byte, sizeofUnixSocketRequest)}
b.Write(r.Family)
b.Write(r.Protocol)
native.PutUint16(b.Next(2), r.pad)
native.PutUint32(b.Next(4), r.States)
native.PutUint32(b.Next(4), r.INode)
native.PutUint32(b.Next(4), r.Show)
native.PutUint32(b.Next(4), r.Cookie[0])
native.PutUint32(b.Next(4), r.Cookie[1])
return b.Bytes
}
func (r *unixSocketRequest) Len() int { return sizeofUnixSocketRequest }
type readBuffer struct {
Bytes []byte
pos int
}
func (b *readBuffer) Read() byte {
c := b.Bytes[b.pos]
b.pos++
return c
}
func (b *readBuffer) Next(n int) []byte {
s := b.Bytes[b.pos : b.pos+n]
b.pos += n
return s
}
func (s *Socket) deserialize(b []byte) error {
if len(b) < sizeofSocket {
return fmt.Errorf("socket data short read (%d); want %d", len(b), sizeofSocket)
}
rb := readBuffer{Bytes: b}
s.Family = rb.Read()
s.State = rb.Read()
s.Timer = rb.Read()
s.Retrans = rb.Read()
s.ID.SourcePort = networkOrder.Uint16(rb.Next(2))
s.ID.DestinationPort = networkOrder.Uint16(rb.Next(2))
if s.Family == unix.AF_INET6 {
s.ID.Source = net.IP(rb.Next(16))
s.ID.Destination = net.IP(rb.Next(16))
} else {
s.ID.Source = net.IPv4(rb.Read(), rb.Read(), rb.Read(), rb.Read())
rb.Next(12)
s.ID.Destination = net.IPv4(rb.Read(), rb.Read(), rb.Read(), rb.Read())
rb.Next(12)
}
s.ID.Interface = native.Uint32(rb.Next(4))
s.ID.Cookie[0] = native.Uint32(rb.Next(4))
s.ID.Cookie[1] = native.Uint32(rb.Next(4))
s.Expires = native.Uint32(rb.Next(4))
s.RQueue = native.Uint32(rb.Next(4))
s.WQueue = native.Uint32(rb.Next(4))
s.UID = native.Uint32(rb.Next(4))
s.INode = native.Uint32(rb.Next(4))
return nil
}
func (u *UnixSocket) deserialize(b []byte) error {
if len(b) < sizeofUnixSocket {
return fmt.Errorf("unix diag data short read (%d); want %d", len(b), sizeofUnixSocket)
}
rb := readBuffer{Bytes: b}
u.Type = rb.Read()
u.Family = rb.Read()
u.State = rb.Read()
u.pad = rb.Read()
u.INode = native.Uint32(rb.Next(4))
u.Cookie[0] = native.Uint32(rb.Next(4))
u.Cookie[1] = native.Uint32(rb.Next(4))
return nil
}
// SocketGet returns the Socket identified by its local and remote addresses.
func (h *Handle) SocketGet(local, remote net.Addr) (*Socket, error) {
var protocol uint8
var localIP, remoteIP net.IP
var localPort, remotePort uint16
switch l := local.(type) {
case *net.TCPAddr:
r, ok := remote.(*net.TCPAddr)
if !ok {
return nil, ErrNotImplemented
}
localIP = l.IP
localPort = uint16(l.Port)
remoteIP = r.IP
remotePort = uint16(r.Port)
protocol = unix.IPPROTO_TCP
case *net.UDPAddr:
r, ok := remote.(*net.UDPAddr)
if !ok {
return nil, ErrNotImplemented
}
localIP = l.IP
localPort = uint16(l.Port)
remoteIP = r.IP
remotePort = uint16(r.Port)
protocol = unix.IPPROTO_UDP
default:
return nil, ErrNotImplemented
}
var family uint8
if localIP.To4() != nil && remoteIP.To4() != nil {
family = unix.AF_INET
}
if family == 0 && localIP.To16() != nil && remoteIP.To16() != nil {
family = unix.AF_INET6
}
if family == 0 {
return nil, ErrNotImplemented
}
req := h.newNetlinkRequest(nl.SOCK_DIAG_BY_FAMILY, unix.NLM_F_DUMP)
req.AddData(&socketRequest{
Family: family,
Protocol: protocol,
States: 0xffffffff,
ID: SocketID{
SourcePort: localPort,
DestinationPort: remotePort,
Source: localIP,
Destination: remoteIP,
Cookie: [2]uint32{nl.TCPDIAG_NOCOOKIE, nl.TCPDIAG_NOCOOKIE},
},
})
msgs, err := req.Execute(unix.NETLINK_INET_DIAG, nl.SOCK_DIAG_BY_FAMILY)
if err != nil {
return nil, err
}
if len(msgs) == 0 {
return nil, errors.New("no message nor error from netlink")
}
if len(msgs) > 2 {
return nil, fmt.Errorf("multiple (%d) matching sockets", len(msgs))
}
sock := &Socket{}
if err := sock.deserialize(msgs[0]); err != nil {
return nil, err
}
return sock, nil
}
// SocketGet returns the Socket identified by its local and remote addresses.
func SocketGet(local, remote net.Addr) (*Socket, error) {
return pkgHandle.SocketGet(local, remote)
}
// SocketDestroy kills the Socket identified by its local and remote addresses.
func (h *Handle) SocketDestroy(local, remote net.Addr) error {
localTCP, ok := local.(*net.TCPAddr)
if !ok {
return ErrNotImplemented
}
remoteTCP, ok := remote.(*net.TCPAddr)
if !ok {
return ErrNotImplemented
}
localIP := localTCP.IP.To4()
if localIP == nil {
return ErrNotImplemented
}
remoteIP := remoteTCP.IP.To4()
if remoteIP == nil {
return ErrNotImplemented
}
s, err := nl.Subscribe(unix.NETLINK_INET_DIAG)
if err != nil {
return err
}
defer s.Close()
req := h.newNetlinkRequest(nl.SOCK_DESTROY, unix.NLM_F_ACK)
req.AddData(&socketRequest{
Family: unix.AF_INET,
Protocol: unix.IPPROTO_TCP,
ID: SocketID{
SourcePort: uint16(localTCP.Port),
DestinationPort: uint16(remoteTCP.Port),
Source: localIP,
Destination: remoteIP,
Cookie: [2]uint32{nl.TCPDIAG_NOCOOKIE, nl.TCPDIAG_NOCOOKIE},
},
})
_, err = req.Execute(unix.NETLINK_INET_DIAG, 0)
return err
}
// SocketDestroy kills the Socket identified by its local and remote addresses.
func SocketDestroy(local, remote net.Addr) error {
return pkgHandle.SocketDestroy(local, remote)
}
// SocketDiagTCPInfo requests INET_DIAG_INFO for TCP protocol for specified family type and return with extension TCP info.
func (h *Handle) SocketDiagTCPInfo(family uint8) ([]*InetDiagTCPInfoResp, error) {
// Construct the request
req := h.newNetlinkRequest(nl.SOCK_DIAG_BY_FAMILY, unix.NLM_F_DUMP)
req.AddData(&socketRequest{
Family: family,
Protocol: unix.IPPROTO_TCP,
Ext: (1 << (INET_DIAG_VEGASINFO - 1)) | (1 << (INET_DIAG_INFO - 1)),
States: uint32(0xfff), // all states
})
// Do the query and parse the result
var result []*InetDiagTCPInfoResp
var err error
err = req.ExecuteIter(unix.NETLINK_INET_DIAG, nl.SOCK_DIAG_BY_FAMILY, func(msg []byte) bool {
sockInfo := &Socket{}
if err = sockInfo.deserialize(msg); err != nil {
return false
}
var attrs []syscall.NetlinkRouteAttr
if attrs, err = nl.ParseRouteAttr(msg[sizeofSocket:]); err != nil {
return false
}
var res *InetDiagTCPInfoResp
if res, err = attrsToInetDiagTCPInfoResp(attrs, sockInfo); err != nil {
return false
}
result = append(result, res)
return true
})
if err != nil {
return nil, err
}
return result, nil
}
// SocketDiagTCPInfo requests INET_DIAG_INFO for TCP protocol for specified family type and return with extension TCP info.
func SocketDiagTCPInfo(family uint8) ([]*InetDiagTCPInfoResp, error) {
return pkgHandle.SocketDiagTCPInfo(family)
}
// SocketDiagTCP requests INET_DIAG_INFO for TCP protocol for specified family type and return related socket.
func (h *Handle) SocketDiagTCP(family uint8) ([]*Socket, error) {
// Construct the request
req := h.newNetlinkRequest(nl.SOCK_DIAG_BY_FAMILY, unix.NLM_F_DUMP)
req.AddData(&socketRequest{
Family: family,
Protocol: unix.IPPROTO_TCP,
Ext: (1 << (INET_DIAG_VEGASINFO - 1)) | (1 << (INET_DIAG_INFO - 1)),
States: uint32(0xfff), // all states
})
// Do the query and parse the result
var result []*Socket
var err error
err = req.ExecuteIter(unix.NETLINK_INET_DIAG, nl.SOCK_DIAG_BY_FAMILY, func(msg []byte) bool {
sockInfo := &Socket{}
if err = sockInfo.deserialize(msg); err != nil {
return false
}
result = append(result, sockInfo)
return true
})
if err != nil {
return nil, err
}
return result, nil
}
// SocketDiagTCP requests INET_DIAG_INFO for TCP protocol for specified family type and return related socket.
func SocketDiagTCP(family uint8) ([]*Socket, error) {
return pkgHandle.SocketDiagTCP(family)
}
// SocketDiagUDPInfo requests INET_DIAG_INFO for UDP protocol for specified family type and return with extension info.
func (h *Handle) SocketDiagUDPInfo(family uint8) ([]*InetDiagUDPInfoResp, error) {
// Construct the request
var extensions uint8
extensions = 1 << (INET_DIAG_VEGASINFO - 1)
extensions |= 1 << (INET_DIAG_INFO - 1)
extensions |= 1 << (INET_DIAG_MEMINFO - 1)
req := h.newNetlinkRequest(nl.SOCK_DIAG_BY_FAMILY, unix.NLM_F_DUMP)
req.AddData(&socketRequest{
Family: family,
Protocol: unix.IPPROTO_UDP,
Ext: extensions,
States: uint32(0xfff), // all states
})
// Do the query and parse the result
var result []*InetDiagUDPInfoResp
var err error
err = req.ExecuteIter(unix.NETLINK_INET_DIAG, nl.SOCK_DIAG_BY_FAMILY, func(msg []byte) bool {
sockInfo := &Socket{}
if err = sockInfo.deserialize(msg); err != nil {
return false
}
var attrs []syscall.NetlinkRouteAttr
if attrs, err = nl.ParseRouteAttr(msg[sizeofSocket:]); err != nil {
return false
}
var res *InetDiagUDPInfoResp
if res, err = attrsToInetDiagUDPInfoResp(attrs, sockInfo); err != nil {
return false
}
result = append(result, res)
return true
})
if err != nil {
return nil, err
}
return result, nil
}
// SocketDiagUDPInfo requests INET_DIAG_INFO for UDP protocol for specified family type and return with extension info.
func SocketDiagUDPInfo(family uint8) ([]*InetDiagUDPInfoResp, error) {
return pkgHandle.SocketDiagUDPInfo(family)
}
// SocketDiagUDP requests INET_DIAG_INFO for UDP protocol for specified family type and return related socket.
func (h *Handle) SocketDiagUDP(family uint8) ([]*Socket, error) {
// Construct the request
req := h.newNetlinkRequest(nl.SOCK_DIAG_BY_FAMILY, unix.NLM_F_DUMP)
req.AddData(&socketRequest{
Family: family,
Protocol: unix.IPPROTO_UDP,
Ext: (1 << (INET_DIAG_VEGASINFO - 1)) | (1 << (INET_DIAG_INFO - 1)),
States: uint32(0xfff), // all states
})
// Do the query and parse the result
var result []*Socket
var err error
err = req.ExecuteIter(unix.NETLINK_INET_DIAG, nl.SOCK_DIAG_BY_FAMILY, func(msg []byte) bool {
sockInfo := &Socket{}
if err = sockInfo.deserialize(msg); err != nil {
return false
}
result = append(result, sockInfo)
return true
})
if err != nil {
return nil, err
}
return result, nil
}
// SocketDiagUDP requests INET_DIAG_INFO for UDP protocol for specified family type and return related socket.
func SocketDiagUDP(family uint8) ([]*Socket, error) {
return pkgHandle.SocketDiagUDP(family)
}
// UnixSocketDiagInfo requests UNIX_DIAG_INFO for unix sockets and return with extension info.
func (h *Handle) UnixSocketDiagInfo() ([]*UnixDiagInfoResp, error) {
// Construct the request
var extensions uint8
extensions = 1 << UNIX_DIAG_NAME
extensions |= 1 << UNIX_DIAG_PEER
extensions |= 1 << UNIX_DIAG_RQLEN
req := h.newNetlinkRequest(nl.SOCK_DIAG_BY_FAMILY, unix.NLM_F_DUMP)
req.AddData(&unixSocketRequest{
Family: unix.AF_UNIX,
States: ^uint32(0), // all states
Show: uint32(extensions),
})
var result []*UnixDiagInfoResp
var err error
err = req.ExecuteIter(unix.NETLINK_INET_DIAG, nl.SOCK_DIAG_BY_FAMILY, func(msg []byte) bool {
sockInfo := &UnixSocket{}
if err = sockInfo.deserialize(msg); err != nil {
return false
}
// Diagnosis also delivers sockets with AF_INET family, filter those
if sockInfo.Family != unix.AF_UNIX {
return false
}
var attrs []syscall.NetlinkRouteAttr
if attrs, err = nl.ParseRouteAttr(msg[sizeofSocket:]); err != nil {
return false
}
var res *UnixDiagInfoResp
if res, err = attrsToUnixDiagInfoResp(attrs, sockInfo); err != nil {
return false
}
result = append(result, res)
return true
})
if err != nil {
return nil, err
}
return result, nil
}
// UnixSocketDiagInfo requests UNIX_DIAG_INFO for unix sockets and return with extension info.
func UnixSocketDiagInfo() ([]*UnixDiagInfoResp, error) {
return pkgHandle.UnixSocketDiagInfo()
}
// UnixSocketDiag requests UNIX_DIAG_INFO for unix sockets.
func (h *Handle) UnixSocketDiag() ([]*UnixSocket, error) {
// Construct the request
req := h.newNetlinkRequest(nl.SOCK_DIAG_BY_FAMILY, unix.NLM_F_DUMP)
req.AddData(&unixSocketRequest{
Family: unix.AF_UNIX,
States: ^uint32(0), // all states
})
var result []*UnixSocket
var err error
err = req.ExecuteIter(unix.NETLINK_INET_DIAG, nl.SOCK_DIAG_BY_FAMILY, func(msg []byte) bool {
sockInfo := &UnixSocket{}
if err = sockInfo.deserialize(msg); err != nil {
return false
}
// Diagnosis also delivers sockets with AF_INET family, filter those
if sockInfo.Family == unix.AF_UNIX {
result = append(result, sockInfo)
}
return true
})
if err != nil {
return nil, err
}
return result, nil
}
// UnixSocketDiag requests UNIX_DIAG_INFO for unix sockets.
func UnixSocketDiag() ([]*UnixSocket, error) {
return pkgHandle.UnixSocketDiag()
}
func attrsToInetDiagTCPInfoResp(attrs []syscall.NetlinkRouteAttr, sockInfo *Socket) (*InetDiagTCPInfoResp, error) {
info := &InetDiagTCPInfoResp{
InetDiagMsg: sockInfo,
}
for _, a := range attrs {
switch a.Attr.Type {
case INET_DIAG_INFO:
info.TCPInfo = &TCPInfo{}
if err := info.TCPInfo.deserialize(a.Value); err != nil {
return nil, err
}
case INET_DIAG_BBRINFO:
info.TCPBBRInfo = &TCPBBRInfo{}
if err := info.TCPBBRInfo.deserialize(a.Value); err != nil {
return nil, err
}
}
}
return info, nil
}
func attrsToInetDiagUDPInfoResp(attrs []syscall.NetlinkRouteAttr, sockInfo *Socket) (*InetDiagUDPInfoResp, error) {
info := &InetDiagUDPInfoResp{
InetDiagMsg: sockInfo,
}
for _, a := range attrs {
switch a.Attr.Type {
case INET_DIAG_MEMINFO:
info.Memory = &MemInfo{}
if err := info.Memory.deserialize(a.Value); err != nil {
return nil, err
}
}
}
return info, nil
}
func attrsToUnixDiagInfoResp(attrs []syscall.NetlinkRouteAttr, sockInfo *UnixSocket) (*UnixDiagInfoResp, error) {
info := &UnixDiagInfoResp{
DiagMsg: sockInfo,
}
for _, a := range attrs {
switch a.Attr.Type {
case UNIX_DIAG_NAME:
name := string(a.Value[:a.Attr.Len])
info.Name = &name
case UNIX_DIAG_PEER:
peer := native.Uint32(a.Value)
info.Peer = &peer
case UNIX_DIAG_RQLEN:
info.Queue = &QueueInfo{
RQueue: native.Uint32(a.Value[:4]),
WQueue: native.Uint32(a.Value[4:]),
}
// default:
// fmt.Println("unknown unix attribute type", a.Attr.Type, "with data", a.Value)
}
}
return info, nil
}
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