audit.go

package k8ssshpod

import (
	"bufio"
	"errors"
	"io"
	"log"

	"github.com/gliderlabs/ssh"
)

// audit log from ssh session input command
func auditLog(s ssh.Session, isAudit bool) (io.Reader, func()) {
	if isAudit {
		// split ssh session for kubernetes api exec
		podReader, podWriter := io.Pipe()
		// split ssh session for audit logging
		auditReader, auditWriter := io.Pipe()

		go func() {
			io.Copy(io.MultiWriter(podWriter, auditWriter), s)
		}()

		go func() {
			// record audit log
			br := bufio.NewReader(auditReader)
			for {
				line, err := br.ReadString('\r')
				if err != nil {
					if errors.Is(err, io.EOF) || errors.Is(err, io.ErrClosedPipe) {
						return
					} else {
						panic(err)
					}
				}
				log.Printf("audit log: username: %s command: %s", s.User(), string(line))
			}
		}()

		return podReader, func() {
			podReader.Close()
			podWriter.Close()
			auditReader.Close()
			auditWriter.Close()
		}
	}
	return s, nil
}