mirror of
https://github.com/slackhq/nebula.git
synced 2025-11-22 16:34:25 +01:00
497 lines
12 KiB
Go
497 lines
12 KiB
Go
//go:build !android && !e2e_testing
|
|
// +build !android,!e2e_testing
|
|
|
|
package udp
|
|
|
|
import (
|
|
"encoding/binary"
|
|
"fmt"
|
|
"net"
|
|
"net/netip"
|
|
"syscall"
|
|
"unsafe"
|
|
|
|
"github.com/rcrowley/go-metrics"
|
|
"github.com/sirupsen/logrus"
|
|
"github.com/slackhq/nebula/config"
|
|
"golang.org/x/sys/unix"
|
|
)
|
|
|
|
type StdConn struct {
|
|
sysFd int
|
|
isV4 bool
|
|
l *logrus.Logger
|
|
batch int
|
|
|
|
// Pre-allocated buffers for batch writes (sized for IPv6, works for both)
|
|
writeMsgs []rawMessage
|
|
writeIovecs []iovec
|
|
writeNames [][]byte
|
|
}
|
|
|
|
func maybeIPV4(ip net.IP) (net.IP, bool) {
|
|
ip4 := ip.To4()
|
|
if ip4 != nil {
|
|
return ip4, true
|
|
}
|
|
return ip, false
|
|
}
|
|
|
|
func NewListener(l *logrus.Logger, ip netip.Addr, port int, multi bool, batch int) (Conn, error) {
|
|
af := unix.AF_INET6
|
|
if ip.Is4() {
|
|
af = unix.AF_INET
|
|
}
|
|
syscall.ForkLock.RLock()
|
|
fd, err := unix.Socket(af, unix.SOCK_DGRAM, unix.IPPROTO_UDP)
|
|
if err == nil {
|
|
unix.CloseOnExec(fd)
|
|
}
|
|
syscall.ForkLock.RUnlock()
|
|
|
|
if err != nil {
|
|
unix.Close(fd)
|
|
return nil, fmt.Errorf("unable to open socket: %s", err)
|
|
}
|
|
|
|
if multi {
|
|
if err = unix.SetsockoptInt(fd, unix.SOL_SOCKET, unix.SO_REUSEPORT, 1); err != nil {
|
|
return nil, fmt.Errorf("unable to set SO_REUSEPORT: %s", err)
|
|
}
|
|
}
|
|
|
|
var sa unix.Sockaddr
|
|
if ip.Is4() {
|
|
sa4 := &unix.SockaddrInet4{Port: port}
|
|
sa4.Addr = ip.As4()
|
|
sa = sa4
|
|
} else {
|
|
sa6 := &unix.SockaddrInet6{Port: port}
|
|
sa6.Addr = ip.As16()
|
|
sa = sa6
|
|
}
|
|
if err = unix.Bind(fd, sa); err != nil {
|
|
return nil, fmt.Errorf("unable to bind to socket: %s", err)
|
|
}
|
|
|
|
c := &StdConn{sysFd: fd, isV4: ip.Is4(), l: l, batch: batch}
|
|
|
|
// Pre-allocate write message structures for batching (sized for IPv6, works for both)
|
|
c.writeMsgs = make([]rawMessage, batch)
|
|
c.writeIovecs = make([]iovec, batch)
|
|
c.writeNames = make([][]byte, batch)
|
|
|
|
for i := range c.writeMsgs {
|
|
// Allocate for IPv6 size (larger than IPv4, works for both)
|
|
c.writeNames[i] = make([]byte, unix.SizeofSockaddrInet6)
|
|
|
|
// Point to the iovec in the slice
|
|
c.writeMsgs[i].Hdr.Iov = &c.writeIovecs[i]
|
|
c.writeMsgs[i].Hdr.Iovlen = 1
|
|
|
|
c.writeMsgs[i].Hdr.Name = &c.writeNames[i][0]
|
|
// Namelen will be set appropriately in writeMulti4/writeMulti6
|
|
}
|
|
|
|
return c, err
|
|
}
|
|
|
|
func (u *StdConn) Rebind() error {
|
|
return nil
|
|
}
|
|
|
|
func (u *StdConn) SetRecvBuffer(n int) error {
|
|
return unix.SetsockoptInt(u.sysFd, unix.SOL_SOCKET, unix.SO_RCVBUFFORCE, n)
|
|
}
|
|
|
|
func (u *StdConn) SetSendBuffer(n int) error {
|
|
return unix.SetsockoptInt(u.sysFd, unix.SOL_SOCKET, unix.SO_SNDBUFFORCE, n)
|
|
}
|
|
|
|
func (u *StdConn) SetSoMark(mark int) error {
|
|
return unix.SetsockoptInt(u.sysFd, unix.SOL_SOCKET, unix.SO_MARK, mark)
|
|
}
|
|
|
|
func (u *StdConn) GetRecvBuffer() (int, error) {
|
|
return unix.GetsockoptInt(int(u.sysFd), unix.SOL_SOCKET, unix.SO_RCVBUF)
|
|
}
|
|
|
|
func (u *StdConn) GetSendBuffer() (int, error) {
|
|
return unix.GetsockoptInt(int(u.sysFd), unix.SOL_SOCKET, unix.SO_SNDBUF)
|
|
}
|
|
|
|
func (u *StdConn) GetSoMark() (int, error) {
|
|
return unix.GetsockoptInt(int(u.sysFd), unix.SOL_SOCKET, unix.SO_MARK)
|
|
}
|
|
|
|
func (u *StdConn) LocalAddr() (netip.AddrPort, error) {
|
|
sa, err := unix.Getsockname(u.sysFd)
|
|
if err != nil {
|
|
return netip.AddrPort{}, err
|
|
}
|
|
|
|
switch sa := sa.(type) {
|
|
case *unix.SockaddrInet4:
|
|
return netip.AddrPortFrom(netip.AddrFrom4(sa.Addr), uint16(sa.Port)), nil
|
|
|
|
case *unix.SockaddrInet6:
|
|
return netip.AddrPortFrom(netip.AddrFrom16(sa.Addr), uint16(sa.Port)), nil
|
|
|
|
default:
|
|
return netip.AddrPort{}, fmt.Errorf("unsupported sock type: %T", sa)
|
|
}
|
|
}
|
|
|
|
func (u *StdConn) ListenOut(r EncReader) {
|
|
var ip netip.Addr
|
|
|
|
msgs, buffers, names := u.PrepareRawMessages(u.batch)
|
|
read := u.ReadMulti
|
|
if u.batch == 1 {
|
|
read = u.ReadSingle
|
|
}
|
|
|
|
for {
|
|
n, err := read(msgs)
|
|
if err != nil {
|
|
u.l.WithError(err).Debug("udp socket is closed, exiting read loop")
|
|
return
|
|
}
|
|
|
|
for i := 0; i < n; i++ {
|
|
// Its ok to skip the ok check here, the slicing is the only error that can occur and it will panic
|
|
if u.isV4 {
|
|
ip, _ = netip.AddrFromSlice(names[i][4:8])
|
|
} else {
|
|
ip, _ = netip.AddrFromSlice(names[i][8:24])
|
|
}
|
|
r(netip.AddrPortFrom(ip.Unmap(), binary.BigEndian.Uint16(names[i][2:4])), buffers[i][:msgs[i].Len])
|
|
}
|
|
}
|
|
}
|
|
|
|
func (u *StdConn) ReadSingle(msgs []rawMessage) (int, error) {
|
|
for {
|
|
n, _, err := unix.Syscall6(
|
|
unix.SYS_RECVMSG,
|
|
uintptr(u.sysFd),
|
|
uintptr(unsafe.Pointer(&(msgs[0].Hdr))),
|
|
0,
|
|
0,
|
|
0,
|
|
0,
|
|
)
|
|
|
|
if err != 0 {
|
|
return 0, &net.OpError{Op: "recvmsg", Err: err}
|
|
}
|
|
|
|
msgs[0].Len = uint32(n)
|
|
return 1, nil
|
|
}
|
|
}
|
|
|
|
func (u *StdConn) ReadMulti(msgs []rawMessage) (int, error) {
|
|
for {
|
|
n, _, err := unix.Syscall6(
|
|
unix.SYS_RECVMMSG,
|
|
uintptr(u.sysFd),
|
|
uintptr(unsafe.Pointer(&msgs[0])),
|
|
uintptr(len(msgs)),
|
|
unix.MSG_WAITFORONE,
|
|
0,
|
|
0,
|
|
)
|
|
|
|
if err != 0 {
|
|
return 0, &net.OpError{Op: "recvmmsg", Err: err}
|
|
}
|
|
|
|
return int(n), nil
|
|
}
|
|
}
|
|
|
|
func (u *StdConn) WriteTo(b []byte, ip netip.AddrPort) error {
|
|
if u.isV4 {
|
|
return u.writeTo4(b, ip)
|
|
}
|
|
return u.writeTo6(b, ip)
|
|
}
|
|
|
|
func (u *StdConn) WriteMulti(packets [][]byte, addrs []netip.AddrPort) (int, error) {
|
|
if len(packets) != len(addrs) {
|
|
return 0, fmt.Errorf("packets and addrs length mismatch")
|
|
}
|
|
if len(packets) == 0 {
|
|
return 0, nil
|
|
}
|
|
if u.isV4 {
|
|
return u.writeMulti4(packets, addrs)
|
|
}
|
|
return u.writeMulti6(packets, addrs)
|
|
}
|
|
|
|
func (u *StdConn) writeTo6(b []byte, ip netip.AddrPort) error {
|
|
var rsa unix.RawSockaddrInet6
|
|
rsa.Family = unix.AF_INET6
|
|
rsa.Addr = ip.Addr().As16()
|
|
binary.BigEndian.PutUint16((*[2]byte)(unsafe.Pointer(&rsa.Port))[:], ip.Port())
|
|
|
|
for {
|
|
_, _, err := unix.Syscall6(
|
|
unix.SYS_SENDTO,
|
|
uintptr(u.sysFd),
|
|
uintptr(unsafe.Pointer(&b[0])),
|
|
uintptr(len(b)),
|
|
uintptr(0),
|
|
uintptr(unsafe.Pointer(&rsa)),
|
|
uintptr(unix.SizeofSockaddrInet6),
|
|
)
|
|
|
|
if err != 0 {
|
|
return &net.OpError{Op: "sendto", Err: err}
|
|
}
|
|
|
|
return nil
|
|
}
|
|
}
|
|
|
|
func (u *StdConn) writeTo4(b []byte, ip netip.AddrPort) error {
|
|
if !ip.Addr().Is4() {
|
|
return ErrInvalidIPv6RemoteForSocket
|
|
}
|
|
|
|
var rsa unix.RawSockaddrInet4
|
|
rsa.Family = unix.AF_INET
|
|
rsa.Addr = ip.Addr().As4()
|
|
binary.BigEndian.PutUint16((*[2]byte)(unsafe.Pointer(&rsa.Port))[:], ip.Port())
|
|
|
|
for {
|
|
_, _, err := unix.Syscall6(
|
|
unix.SYS_SENDTO,
|
|
uintptr(u.sysFd),
|
|
uintptr(unsafe.Pointer(&b[0])),
|
|
uintptr(len(b)),
|
|
uintptr(0),
|
|
uintptr(unsafe.Pointer(&rsa)),
|
|
uintptr(unix.SizeofSockaddrInet4),
|
|
)
|
|
|
|
if err != 0 {
|
|
return &net.OpError{Op: "sendto", Err: err}
|
|
}
|
|
|
|
return nil
|
|
}
|
|
}
|
|
|
|
func (u *StdConn) writeMulti4(packets [][]byte, addrs []netip.AddrPort) (int, error) {
|
|
sent := 0
|
|
for sent < len(packets) {
|
|
// Determine batch size based on remaining packets and buffer capacity
|
|
batchSize := len(packets) - sent
|
|
if batchSize > len(u.writeMsgs) {
|
|
batchSize = len(u.writeMsgs)
|
|
}
|
|
|
|
// Use pre-allocated buffers
|
|
msgs := u.writeMsgs[:batchSize]
|
|
iovecs := u.writeIovecs[:batchSize]
|
|
names := u.writeNames[:batchSize]
|
|
|
|
// Setup message structures for this batch
|
|
for i := 0; i < batchSize; i++ {
|
|
pktIdx := sent + i
|
|
if !addrs[pktIdx].Addr().Is4() {
|
|
return sent + i, ErrInvalidIPv6RemoteForSocket
|
|
}
|
|
|
|
// Setup the packet buffer
|
|
iovecs[i].Base = &packets[pktIdx][0]
|
|
iovecs[i].Len = uint(len(packets[pktIdx]))
|
|
|
|
// Setup the destination address
|
|
rsa := (*unix.RawSockaddrInet4)(unsafe.Pointer(&names[i][0]))
|
|
rsa.Family = unix.AF_INET
|
|
rsa.Addr = addrs[pktIdx].Addr().As4()
|
|
binary.BigEndian.PutUint16((*[2]byte)(unsafe.Pointer(&rsa.Port))[:], addrs[pktIdx].Port())
|
|
|
|
// Set the appropriate address length for IPv4
|
|
msgs[i].Hdr.Namelen = unix.SizeofSockaddrInet4
|
|
}
|
|
|
|
// Send this batch
|
|
nsent, _, err := unix.Syscall6(
|
|
unix.SYS_SENDMMSG,
|
|
uintptr(u.sysFd),
|
|
uintptr(unsafe.Pointer(&msgs[0])),
|
|
uintptr(batchSize),
|
|
0,
|
|
0,
|
|
0,
|
|
)
|
|
|
|
if err != 0 {
|
|
return sent + int(nsent), &net.OpError{Op: "sendmmsg", Err: err}
|
|
}
|
|
|
|
sent += int(nsent)
|
|
if int(nsent) < batchSize {
|
|
// Couldn't send all packets in batch, return what we sent
|
|
return sent, nil
|
|
}
|
|
}
|
|
|
|
return sent, nil
|
|
}
|
|
|
|
func (u *StdConn) writeMulti6(packets [][]byte, addrs []netip.AddrPort) (int, error) {
|
|
sent := 0
|
|
for sent < len(packets) {
|
|
// Determine batch size based on remaining packets and buffer capacity
|
|
batchSize := len(packets) - sent
|
|
if batchSize > len(u.writeMsgs) {
|
|
batchSize = len(u.writeMsgs)
|
|
}
|
|
|
|
// Use pre-allocated buffers
|
|
msgs := u.writeMsgs[:batchSize]
|
|
iovecs := u.writeIovecs[:batchSize]
|
|
names := u.writeNames[:batchSize]
|
|
|
|
// Setup message structures for this batch
|
|
for i := 0; i < batchSize; i++ {
|
|
pktIdx := sent + i
|
|
|
|
// Setup the packet buffer
|
|
iovecs[i].Base = &packets[pktIdx][0]
|
|
iovecs[i].Len = uint(len(packets[pktIdx]))
|
|
|
|
// Setup the destination address
|
|
rsa := (*unix.RawSockaddrInet6)(unsafe.Pointer(&names[i][0]))
|
|
rsa.Family = unix.AF_INET6
|
|
rsa.Addr = addrs[pktIdx].Addr().As16()
|
|
binary.BigEndian.PutUint16((*[2]byte)(unsafe.Pointer(&rsa.Port))[:], addrs[pktIdx].Port())
|
|
|
|
// Set the appropriate address length for IPv6
|
|
msgs[i].Hdr.Namelen = unix.SizeofSockaddrInet6
|
|
}
|
|
|
|
// Send this batch
|
|
nsent, _, err := unix.Syscall6(
|
|
unix.SYS_SENDMMSG,
|
|
uintptr(u.sysFd),
|
|
uintptr(unsafe.Pointer(&msgs[0])),
|
|
uintptr(batchSize),
|
|
0,
|
|
0,
|
|
0,
|
|
)
|
|
|
|
if err != 0 {
|
|
return sent + int(nsent), &net.OpError{Op: "sendmmsg", Err: err}
|
|
}
|
|
|
|
sent += int(nsent)
|
|
if int(nsent) < batchSize {
|
|
// Couldn't send all packets in batch, return what we sent
|
|
return sent, nil
|
|
}
|
|
}
|
|
|
|
return sent, nil
|
|
}
|
|
|
|
func (u *StdConn) ReloadConfig(c *config.C) {
|
|
b := c.GetInt("listen.read_buffer", 0)
|
|
if b > 0 {
|
|
err := u.SetRecvBuffer(b)
|
|
if err == nil {
|
|
s, err := u.GetRecvBuffer()
|
|
if err == nil {
|
|
u.l.WithField("size", s).Info("listen.read_buffer was set")
|
|
} else {
|
|
u.l.WithError(err).Warn("Failed to get listen.read_buffer")
|
|
}
|
|
} else {
|
|
u.l.WithError(err).Error("Failed to set listen.read_buffer")
|
|
}
|
|
}
|
|
|
|
b = c.GetInt("listen.write_buffer", 0)
|
|
if b > 0 {
|
|
err := u.SetSendBuffer(b)
|
|
if err == nil {
|
|
s, err := u.GetSendBuffer()
|
|
if err == nil {
|
|
u.l.WithField("size", s).Info("listen.write_buffer was set")
|
|
} else {
|
|
u.l.WithError(err).Warn("Failed to get listen.write_buffer")
|
|
}
|
|
} else {
|
|
u.l.WithError(err).Error("Failed to set listen.write_buffer")
|
|
}
|
|
}
|
|
|
|
b = c.GetInt("listen.so_mark", 0)
|
|
s, err := u.GetSoMark()
|
|
if b > 0 || (err == nil && s != 0) {
|
|
err := u.SetSoMark(b)
|
|
if err == nil {
|
|
s, err := u.GetSoMark()
|
|
if err == nil {
|
|
u.l.WithField("mark", s).Info("listen.so_mark was set")
|
|
} else {
|
|
u.l.WithError(err).Warn("Failed to get listen.so_mark")
|
|
}
|
|
} else {
|
|
u.l.WithError(err).Error("Failed to set listen.so_mark")
|
|
}
|
|
}
|
|
}
|
|
|
|
func (u *StdConn) getMemInfo(meminfo *[unix.SK_MEMINFO_VARS]uint32) error {
|
|
var vallen uint32 = 4 * unix.SK_MEMINFO_VARS
|
|
_, _, err := unix.Syscall6(unix.SYS_GETSOCKOPT, uintptr(u.sysFd), uintptr(unix.SOL_SOCKET), uintptr(unix.SO_MEMINFO), uintptr(unsafe.Pointer(meminfo)), uintptr(unsafe.Pointer(&vallen)), 0)
|
|
if err != 0 {
|
|
return err
|
|
}
|
|
return nil
|
|
}
|
|
|
|
func (u *StdConn) Close() error {
|
|
return syscall.Close(u.sysFd)
|
|
}
|
|
|
|
func NewUDPStatsEmitter(udpConns []Conn) func() {
|
|
// Check if our kernel supports SO_MEMINFO before registering the gauges
|
|
var udpGauges [][unix.SK_MEMINFO_VARS]metrics.Gauge
|
|
var meminfo [unix.SK_MEMINFO_VARS]uint32
|
|
if err := udpConns[0].(*StdConn).getMemInfo(&meminfo); err == nil {
|
|
udpGauges = make([][unix.SK_MEMINFO_VARS]metrics.Gauge, len(udpConns))
|
|
for i := range udpConns {
|
|
udpGauges[i] = [unix.SK_MEMINFO_VARS]metrics.Gauge{
|
|
metrics.GetOrRegisterGauge(fmt.Sprintf("udp.%d.rmem_alloc", i), nil),
|
|
metrics.GetOrRegisterGauge(fmt.Sprintf("udp.%d.rcvbuf", i), nil),
|
|
metrics.GetOrRegisterGauge(fmt.Sprintf("udp.%d.wmem_alloc", i), nil),
|
|
metrics.GetOrRegisterGauge(fmt.Sprintf("udp.%d.sndbuf", i), nil),
|
|
metrics.GetOrRegisterGauge(fmt.Sprintf("udp.%d.fwd_alloc", i), nil),
|
|
metrics.GetOrRegisterGauge(fmt.Sprintf("udp.%d.wmem_queued", i), nil),
|
|
metrics.GetOrRegisterGauge(fmt.Sprintf("udp.%d.optmem", i), nil),
|
|
metrics.GetOrRegisterGauge(fmt.Sprintf("udp.%d.backlog", i), nil),
|
|
metrics.GetOrRegisterGauge(fmt.Sprintf("udp.%d.drops", i), nil),
|
|
}
|
|
}
|
|
}
|
|
|
|
return func() {
|
|
for i, gauges := range udpGauges {
|
|
if err := udpConns[i].(*StdConn).getMemInfo(&meminfo); err == nil {
|
|
for j := 0; j < unix.SK_MEMINFO_VARS; j++ {
|
|
gauges[j].Update(int64(meminfo[j]))
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|