Change port forwarding on windows

Signed-off-by: Kirtana Ashok <kiashok@microsoft.com>

internal/cri/server/sandbox_portforward_windows.go

@@ -17,61 +17,103 @@
 package server
 
 import (
-	"bytes"
 	"context"
 	"fmt"
 	"io"
+	"net"
+	"time"
 
-	"k8s.io/utils/exec"
+	"github.com/containerd/log"
 
-	sandboxstore "github.com/containerd/containerd/v2/internal/cri/store/sandbox"
-	cioutil "github.com/containerd/containerd/v2/pkg/ioutil"
+	netutils "k8s.io/utils/net"
 )
 
 func (c *criService) portForward(ctx context.Context, id string, port int32, stream io.ReadWriter) error {
-	stdout := cioutil.NewNopWriteCloser(stream)
-	stderrBuffer := new(bytes.Buffer)
-	stderr := cioutil.NewNopWriteCloser(stderrBuffer)
-	// localhost is resolved to 127.0.0.1 in ipv4, and ::1 in ipv6.
-	// Explicitly using ipv4 IP address in here to avoid flakiness.
-	cmd := []string{"wincat.exe", "127.0.0.1", fmt.Sprint(port)}
-	err := c.execInSandbox(ctx, id, cmd, stream, stdout, stderr)
+	sandbox, err := c.sandboxStore.Get(id)
 	if err != nil {
-		return fmt.Errorf("failed to execute port forward in sandbox: %s: %w", stderrBuffer.String(), err)
+		return fmt.Errorf("failed to find sandbox %q in store: %w", id, err)
 	}
+
+	var podIP string
+	if !hostNetwork(sandbox.Config) {
+		// get ip address of the sandbox
+		podIP, _, err = c.getIPs(sandbox)
+		if err != nil {
+			return fmt.Errorf("failed to get sandbox ip: %w", err)
+		}
+	} else {
+		// HPCs use the host networking namespace.
+		// Therefore, dial to localhost.
+		podIP = "127.0.0.1"
+	}
+
+	err = func() error {
+		var conn net.Conn
+		if netutils.IsIPv4String(podIP) {
+			conn, err = net.Dial("tcp4", fmt.Sprintf("%s:%d", podIP, port))
+			if err != nil {
+				return fmt.Errorf("failed to connect to %s:%d for pod %q: %v", podIP, port, id, err)
+			}
+		} else {
+			conn, err = net.Dial("tcp6", fmt.Sprintf("%s:%d", podIP, port))
+			if err != nil {
+				return fmt.Errorf("failed to connect to %s:%d for pod %q: %v", podIP, port, id, err)
+			}
+		}
+		log.G(ctx).Debugf("Connection to ip %s and port %d was successful", podIP, port)
+
+		defer conn.Close()
+
+		// copy stream
+		errCh := make(chan error, 2)
+		// Copy from the namespace port connection to the client stream
+		go func() {
+			log.G(ctx).Debugf("PortForward copying data from namespace %q port %d to the client stream", id, port)
+			_, err := io.Copy(stream, conn)
+			errCh <- err
+		}()
+
+		// Copy from the client stream to the namespace port connection
+		go func() {
+			log.G(ctx).Debugf("PortForward copying data from client stream to namespace %q port %d", id, port)
+			_, err := io.Copy(conn, stream)
+			errCh <- err
+		}()
+
+		// Wait until the first error is returned by one of the connections
+		// we use errFwd to store the result of the port forwarding operation
+		// if the context is cancelled close everything and return
+		var errFwd error
+		select {
+		case errFwd = <-errCh:
+			log.G(ctx).Debugf("PortForward stop forwarding in one direction in network namespace %q port %d: %v", id, port, errFwd)
+		case <-ctx.Done():
+			log.G(ctx).Debugf("PortForward cancelled in network namespace %q port %d: %v", id, port, ctx.Err())
+			return ctx.Err()
+		}
+		// give a chance to terminate gracefully or timeout
+		// after 1s
+		const timeout = time.Second
+		select {
+		case e := <-errCh:
+			if errFwd == nil {
+				errFwd = e
+			}
+			log.G(ctx).Debugf("PortForward stopped forwarding in both directions in network namespace %q port %d: %v", id, port, e)
+		case <-time.After(timeout):
+			log.G(ctx).Debugf("PortForward timed out waiting to close the connection in network namespace %q port %d", id, port)
+		case <-ctx.Done():
+			log.G(ctx).Debugf("PortForward cancelled in network namespace %q port %d: %v", id, port, ctx.Err())
+			errFwd = ctx.Err()
+		}
+
+		return errFwd
+	}()
+
+	if err != nil {
+		return fmt.Errorf("failed to execute portforward for podId %v, podIp %v, err: %w", id, podIP, err)
+	}
+	log.G(ctx).Debugf("Finish port forwarding for windows %q port %d", id, port)
+
 	return nil
 }
-
-func (c *criService) execInSandbox(ctx context.Context, sandboxID string, cmd []string, stdin io.Reader, stdout, stderr io.WriteCloser) error {
-	// Get sandbox from our sandbox store.
-	sb, err := c.sandboxStore.Get(sandboxID)
-	if err != nil {
-		return fmt.Errorf("failed to find sandbox %q in store: %w", sandboxID, err)
-	}
-
-	// Check the sandbox state
-	state := sb.Status.Get().State
-	if state != sandboxstore.StateReady {
-		return fmt.Errorf("sandbox is in %s state", fmt.Sprint(state))
-	}
-
-	opts := execOptions{
-		cmd:    cmd,
-		stdin:  stdin,
-		stdout: stdout,
-		stderr: stderr,
-		tty:    false,
-		resize: nil,
-	}
-	exitCode, err := c.execInternal(ctx, sb.Container, sandboxID, opts)
-	if err != nil {
-		return fmt.Errorf("failed to exec in sandbox: %w", err)
-	}
-	if *exitCode == 0 {
-		return nil
-	}
-	return &exec.CodeExitError{
-		Err:  fmt.Errorf("error executing command %v, exit code %d", cmd, *exitCode),
-		Code: int(*exitCode),
-	}
-}