netbird/client/server/panic_windows.go
2024-11-01 15:08:22 +01:00

84 lines
1.9 KiB
Go

package server
import (
"fmt"
"os"
"path/filepath"
"syscall"
log "github.com/sirupsen/logrus"
"github.com/netbirdio/netbird/util"
)
const (
windowsPanicLogEnvVar = "NB_WINDOWS_PANIC_LOG"
// STD_ERROR_HANDLE ((DWORD)-12) = 4294967284
stdErrorHandle = ^uintptr(11)
)
var (
kernel32 = syscall.NewLazyDLL("kernel32.dll")
// https://learn.microsoft.com/en-us/windows/console/setstdhandle
setStdHandleFn = kernel32.NewProc("SetStdHandle")
)
func handlePanicLog() error {
logPath := os.Getenv(windowsPanicLogEnvVar)
if logPath == "" {
return nil
}
// Ensure the directory exists
logDir := filepath.Dir(logPath)
if err := os.MkdirAll(logDir, 0750); err != nil {
return fmt.Errorf("create panic log directory: %w", err)
}
if err := util.EnforcePermission(logPath); err != nil {
return fmt.Errorf("enforce permission on panic log file: %w", err)
}
// Open log file with append mode
f, err := os.OpenFile(logPath, os.O_WRONLY|os.O_CREATE|os.O_APPEND, 0644)
if err != nil {
return fmt.Errorf("open panic log file: %w", err)
}
// Redirect stderr to the file
if err = redirectStderr(f); err != nil {
if closeErr := f.Close(); closeErr != nil {
log.Warnf("failed to close file after redirect error: %v", closeErr)
}
return fmt.Errorf("redirect stderr: %w", err)
}
log.Infof("successfully configured panic logging to: %s", logPath)
return nil
}
// redirectStderr redirects stderr to the provided file
func redirectStderr(f *os.File) error {
// Get the current process's stderr handle
if err := setStdHandle(f); err != nil {
return fmt.Errorf("failed to set stderr handle: %w", err)
}
// Also set os.Stderr for Go's standard library
os.Stderr = f
return nil
}
func setStdHandle(f *os.File) error {
handle := f.Fd()
r0, _, e1 := setStdHandleFn.Call(stdErrorHandle, handle)
if r0 == 0 {
if e1 != nil {
return e1
}
return syscall.EINVAL
}
return nil
}