Thales Maciel
08ef706e3f
Remind users when a VM is still running after hanger vm ssh exits instead of silently dropping them back to the host shell.\n\nAttach a Firecracker vsock device to each VM, persist the host vsock path/CID,\nadd a new guest-side banger-vsock-pingd responder to the runtime bundle and both\nimage-build paths, and expose a vm.ping RPC that the CLI and TUI call after SSH\nreturns. Doctor and start/build preflight now validate the helper plus\n/dev/vhost-vsock so the feature fails early and clearly.\n\nValidated with go mod tidy, bash -n customize.sh, git diff --check, make build,\nand GOCACHE=/tmp/banger-gocache go test ./... outside the sandbox because the\ndaemon tests need real Unix/UDP sockets. Rebuild the image/rootfs used for new\nVMs so the guest ping service is present.
105 lines
2.4 KiB
Go
105 lines
2.4 KiB
Go
package vsockping
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import (
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"bufio"
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"context"
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"fmt"
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"io"
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"log/slog"
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"net"
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"strings"
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"time"
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sdkvsock "github.com/firecracker-microvm/firecracker-go-sdk/vsock"
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)
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const (
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Port uint32 = 42070
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RequestLine = "PING\n"
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ResponseLine = "PONG\n"
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GuestBinaryName = "banger-vsock-pingd"
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GuestInstallPath = "/usr/local/bin/" + GuestBinaryName
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ServiceName = "banger-vsock-pingd.service"
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serviceUnit = `[Unit]
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Description=Banger vsock ping responder
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After=network.target
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[Service]
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Type=simple
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ExecStart=/usr/local/bin/banger-vsock-pingd
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Restart=on-failure
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RestartSec=1
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[Install]
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WantedBy=multi-user.target
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`
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modulesLoadConfig = "vsock\nvmw_vsock_virtio_transport\n"
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)
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func Ping(ctx context.Context, logger *slog.Logger, socketPath string) error {
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conn, err := sdkvsock.DialContext(
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ctx,
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socketPath,
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Port,
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sdkvsock.WithRetryTimeout(3*time.Second),
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sdkvsock.WithRetryInterval(100*time.Millisecond),
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)
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if err != nil {
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return err
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}
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defer conn.Close()
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if deadline, ok := ctx.Deadline(); ok {
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_ = conn.SetDeadline(deadline)
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} else {
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_ = conn.SetDeadline(time.Now().Add(3 * time.Second))
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}
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if _, err := io.WriteString(conn, RequestLine); err != nil {
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return err
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}
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line, err := bufio.NewReader(conn).ReadString('\n')
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if err != nil {
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return err
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}
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if strings.TrimSpace(line) != strings.TrimSpace(ResponseLine) {
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return fmt.Errorf("unexpected vsock ping response %q", strings.TrimSpace(line))
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}
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if logger != nil {
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logger.Debug("vsock ping ok", "vsock_path", socketPath, "vsock_port", Port)
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}
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return nil
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}
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func ServiceUnit() string {
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return serviceUnit
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}
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func ModulesLoadConfig() string {
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return modulesLoadConfig
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}
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func ReminderMessage(name string) string {
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return fmt.Sprintf("session ended; %s is still running (stop it with 'banger vm stop %s')", name, name)
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}
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func WarningMessage(name string, err error) string {
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if err == nil {
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return ""
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}
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return fmt.Sprintf("warning: failed to check whether %s is still running: %v", name, err)
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}
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func ServeConn(conn net.Conn) error {
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defer conn.Close()
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_ = conn.SetDeadline(time.Now().Add(5 * time.Second))
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line, err := bufio.NewReader(conn).ReadString('\n')
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if err != nil {
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return err
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}
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if strings.TrimSpace(line) != strings.TrimSpace(RequestLine) {
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return fmt.Errorf("unexpected request %q", strings.TrimSpace(line))
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}
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_, err = io.WriteString(conn, ResponseLine)
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return err
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}
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