soypat/lneto
1
0
Fork 0
mirror of https://github.com/soypat/lneto.git synced 2026-07-26 10:38:47 +00:00
Code Issues Packages Projects Releases 1 Wiki Activity

add lock to tcp.Conn; claude Fix ARP handler not responding after DHCP

Browse Source 
Co-authored-by: Claude <noreply@anthropic.com>
This commit is contained in:
Patricio Whittingslow
2025-11-09 14:16:23 -03:00
parent e3c6d68288
commit 7042a653a6
3 changed files with 85 additions and 14 deletions
Download Patch File Download Diff File Expand all files Collapse all files
examples/xnet/main.go
+3
View File
@@ -115,6 +115,9 @@ func run() (err error) {
fmt.Println("ERR:ENCAPSULATE", err)
} else if nwrite > 0 {
frames, err = cap.CaptureEthernet(frames[:0], buf[:nwrite], 0)
if err != nil {
log.Println("ERR capture", err)
}
if len(frames) > 0 {
fmt.Println("OUT", frames)
}
tcp/conn.go
+71 -12
View File
@@ -8,6 +8,7 @@ import (
"net/netip"
"os"
"runtime"
"sync"
"time"
"github.com/soypat/lneto"
@@ -27,6 +28,7 @@ var (
// Note that the complete emulation of [net.TCPConn] at this level of abstraction is yet a non-goal,
// even though the functionality provided is similar.
type Conn struct {
mu sync.Mutex
h Handler
remoteAddr []byte
@@ -46,6 +48,8 @@ type ConnConfig struct {
}
func (conn *Conn) Configure(config ConnConfig) (err error) {
conn.mu.Lock()
defer conn.mu.Unlock()
err = conn.h.SetBuffers(config.TxBuf, config.RxBuf, config.TxPacketQueueSize)
if err != nil {
return err
@@ -55,29 +59,59 @@ func (conn *Conn) Configure(config ConnConfig) (err error) {
}
// LocalPort returns the local port on which the socket is listening or connected to.
func (conn *Conn) LocalPort() uint16 { return conn.h.LocalPort() }
func (conn *Conn) LocalPort() uint16 {
conn.mu.Lock()
defer conn.mu.Unlock()
return conn.h.LocalPort()
}
// RemotePort returns the port of the incoming remote connection. Is non-zero if connection is established.
func (conn *Conn) RemotePort() uint16 { return conn.h.RemotePort() }
func (conn *Conn) RemotePort() uint16 {
conn.mu.Lock()
defer conn.mu.Unlock()
return conn.h.RemotePort()
}
func (conn *Conn) RemoteAddr() []byte { return conn.remoteAddr }
func (conn *Conn) RemoteAddr() []byte {
conn.mu.Lock()
defer conn.mu.Unlock()
return conn.remoteAddr
}
// State returns the TCP state of the socket.
func (conn *Conn) State() State { return conn.h.State() }
func (conn *Conn) State() State {
conn.mu.Lock()
defer conn.mu.Unlock()
return conn.h.State()
}
// BufferedInput returns the number of bytes in the socket's receive(input) buffer
// and available to read via a [Conn.Read] call.
func (conn *Conn) BufferedInput() int { return conn.h.BufferedInput() }
func (conn *Conn) BufferedInput() int {
conn.mu.Lock()
defer conn.mu.Unlock()
return conn.h.BufferedInput()
}
func (conn *Conn) AvailableInput() int { return conn.h.FreeRx() }
func (conn *Conn) AvailableInput() int {
conn.mu.Lock()
defer conn.mu.Unlock()
return conn.h.FreeRx()
}
// AvailableOutput returns amount of bytes available to write to output
// before [Conn.Write] returns an error due to insufficient space to store outgoing data.
func (conn *Conn) AvailableOutput() int { return conn.h.AvailableOutput() }
func (conn *Conn) AvailableOutput() int {
conn.mu.Lock()
defer conn.mu.Unlock()
return conn.h.AvailableOutput()
}
// OpenActive opens a connection to a remote peer with a known IP address and port combination.
// iss is the initial send sequence number which is ideally a random number which is far away from the last sequence number used on a connection to the same host.
func (conn *Conn) OpenActive(localPort uint16, remote netip.AddrPort, iss Value) error {
conn.mu.Lock()
defer conn.mu.Unlock()
if !remote.IsValid() {
return errInvalidIP
}
@@ -100,6 +134,8 @@ func (conn *Conn) OpenActive(localPort uint16, remote netip.AddrPort, iss Value)
// OpenListen opens a passive connection which listens for the first SYN packet to be received on a local port.
// iss is the initial send sequence number which is usually a randomly chosen number.
func (conn *Conn) OpenListen(localPort uint16, iss Value) error {
conn.mu.Lock()
defer conn.mu.Unlock()
err := conn.h.OpenListen(localPort, iss)
if err != nil {
return err
@@ -109,14 +145,19 @@ func (conn *Conn) OpenListen(localPort uint16, iss Value) error {
}
func (conn *Conn) Close() error {
conn.mu.Lock()
defer conn.mu.Unlock()
conn.trace("TCPConn.Close")
return conn.h.Close()
}
// Abort terminates all state of the connection forcibly.
func (conn *Conn) Abort() {
conn.mu.Lock()
defer conn.mu.Unlock()
conn.h.Abort()
*conn = Conn{
mu: conn.mu,
h: conn.h,
remoteAddr: conn.remoteAddr[:0],
logger: conn.logger,
@@ -140,7 +181,7 @@ func (conn *Conn) Write(b []byte) (int, error) {
plen := len(b)
conn.trace("TCPConn.Write:start")
connid := conn.h.ConnectionID()
if conn.deadlineExceeded(conn.wdead) {
if conn.deadlineExceeded(&conn.wdead) {
return 0, errDeadlineExceeded
} else if plen == 0 {
return 0, nil
@@ -153,7 +194,9 @@ func (conn *Conn) Write(b []byte) (int, error) {
} else if connid != conn.h.ConnectionID() {
return n, net.ErrClosed
}
conn.mu.Lock()
ngot, _ := conn.h.Write(b)
conn.mu.Unlock()
n += ngot
b = b[ngot:]
if n == plen {
@@ -165,7 +208,7 @@ func (conn *Conn) Write(b []byte) (int, error) {
backoff.Miss()
}
conn.trace("TCPConn.Write:insuf-buf", slog.Int("missing", plen-n))
if conn.deadlineExceeded(conn.wdead) {
if conn.deadlineExceeded(&conn.wdead) {
return n, errDeadlineExceeded
}
}
@@ -188,12 +231,14 @@ func (conn *Conn) Read(b []byte) (int, error) {
} else if connid != conn.h.ConnectionID() {
return 0, net.ErrClosed
}
if conn.deadlineExceeded(conn.rdead) {
if conn.deadlineExceeded(&conn.rdead) {
return 0, errDeadlineExceeded
}
backoff.Miss()
}
conn.mu.Lock()
n, err := conn.h.Read(b)
conn.mu.Unlock()
return n, err
}
@@ -209,6 +254,8 @@ func (conn *Conn) checkPipeOpen() error {
}
func (conn *Conn) Demux(buf []byte, off int) (err error) {
conn.mu.Lock()
defer conn.mu.Unlock()
conn.trace("tcpconn.Recv:start")
if off >= len(buf) {
return errors.New("bad offset in TCPConn.Recv")
@@ -232,6 +279,8 @@ func (conn *Conn) Demux(buf []byte, off int) (err error) {
}
func (conn *Conn) Encapsulate(buf []byte, off int) (n int, err error) {
conn.mu.Lock()
defer conn.mu.Unlock()
if len(conn.remoteAddr) == 0 {
return 0, errNoRemoteAddr
}
@@ -262,8 +311,12 @@ func (conn *Conn) isRaddrSet() bool {
}
func (conn *Conn) reset(h Handler) {
if conn.mu.TryLock() {
panic("reset must be called from within locked conn")
}
*conn = Conn{
h: h,
mu: conn.mu,
remoteAddr: conn.remoteAddr[:0],
logger: conn.logger,
}
@@ -273,6 +326,8 @@ func (conn *Conn) reset(h Handler) {
// with the connection. It is equivalent to calling both
// SetReadDeadline and SetWriteDeadline. Implements [net.Conn].
func (conn *Conn) SetDeadline(t time.Time) error {
conn.mu.Lock()
defer conn.mu.Unlock()
err := conn.SetReadDeadline(t)
if err != nil {
return err
@@ -283,6 +338,8 @@ func (conn *Conn) SetDeadline(t time.Time) error {
// SetReadDeadline sets the deadline for future Read calls
// and any currently-blocked Read call. A zero value for t means Read will not time out.
func (conn *Conn) SetReadDeadline(t time.Time) error {
conn.mu.Lock()
defer conn.mu.Unlock()
conn.trace("TCPConn.SetReadDeadline:start")
err := conn.checkPipeOpen()
if err == nil {
@@ -305,8 +362,10 @@ func (conn *Conn) SetWriteDeadline(t time.Time) error {
return err
}
func (conn *Conn) deadlineExceeded(deadline time.Time) bool {
return !deadline.IsZero() && time.Since(deadline) > 0
func (conn *Conn) deadlineExceeded(deadline *time.Time) bool {
conn.mu.Lock()
defer conn.mu.Unlock()
return !deadline.IsZero() && time.Since(*deadline) > 0
}
func (conn *Conn) ConnectionID() *uint64 {
x/xnet/stack-async.go
+11 -2
View File
@@ -135,11 +135,11 @@ func (s *StackAsync) Reset(cfg StackConfig) error {
}
// Now setup stacks.
err = s.link.Register(&s.ip) // IPv4 | IPv6
err = s.link.Register(&s.arp) // ARP.
if err != nil {
return err
}
err = s.link.Register(&s.arp) // ARP.
err = s.link.Register(&s.ip) // IPv4 | IPv6
if err != nil {
return err
}
@@ -232,6 +232,8 @@ func (s *StackAsync) Gateway6() [6]byte {
}
func (s *StackAsync) DialTCP(conn *tcp.Conn, localPort uint16, addrp netip.AddrPort) (err error) {
s.mu.Lock()
defer s.mu.Unlock()
err = conn.OpenActive(localPort, addrp, tcp.Value(s.Prand32()))
if err != nil {
return err
@@ -245,6 +247,8 @@ func (s *StackAsync) DialTCP(conn *tcp.Conn, localPort uint16, addrp netip.AddrP
}
func (s *StackAsync) ListenTCP(conn *tcp.Conn, localPort uint16) (err error) {
s.mu.Lock()
defer s.mu.Unlock()
err = conn.OpenListen(localPort, tcp.Value(s.Prand32()))
if err != nil {
return err
@@ -436,6 +440,11 @@ func (stack *StackAsync) AssimilateDHCPResults(results *DHCPResults) error {
if err != nil {
return err
}
// Reset ARP handler with new IP address so it can respond to ARP requests.
err = stack.resetARP()
if err != nil {
return err
}
}
if len(results.DNSServers) > 0 {
if !results.DNSServers[0].IsValid() || !results.DNSServers[0].Is4() {