cloudflared-mirror/sshlog/session_logger.go

72 lines
1.8 KiB
Go

package sshlog
import (
"time"
"github.com/cloudflare/cloudflared/logger"
capnp "zombiezen.com/go/capnproto2"
"zombiezen.com/go/capnproto2/pogs"
)
// SessionLogger will buffer and write events to disk using capnp proto for session replay
type SessionLogger struct {
logger *Logger
encoder *capnp.Encoder
}
type sessionLogData struct {
Timestamp string // The UTC timestamp of when the log occurred
Content []byte // The shell output
}
// NewSessionLogger creates a new session logger by encapsulating a Logger object and writing capnp encoded messages to it
func NewSessionLogger(filename string, logger logger.Service, flushInterval time.Duration, maxFileSize int64) (*SessionLogger, error) {
l, err := NewLogger(filename, logger, flushInterval, maxFileSize)
if err != nil {
return nil, err
}
sessionLogger := &SessionLogger{
logger: l,
encoder: capnp.NewEncoder(l),
}
return sessionLogger, nil
}
// Writes to a log buffer. Implements the io.Writer interface.
func (l *SessionLogger) Write(p []byte) (n int, err error) {
return l.writeSessionLog(&sessionLogData{
Timestamp: time.Now().UTC().Format(time.RFC3339),
Content: p,
})
}
// Close drains anything left in the buffer and cleans up any resources still
// in use.
func (l *SessionLogger) Close() error {
return l.logger.Close()
}
func (l *SessionLogger) writeSessionLog(p *sessionLogData) (int, error) {
msg, seg, err := capnp.NewMessage(capnp.SingleSegment(nil))
if err != nil {
return 0, err
}
log, err := NewRootSessionLog(seg)
if err != nil {
return 0, err
}
log.SetTimestamp(p.Timestamp)
log.SetContent(p.Content)
if err := l.encoder.Encode(msg); err != nil {
return 0, err
}
return len(p.Content), nil
}
func unmarshalSessionLog(s SessionLog) (*sessionLogData, error) {
p := new(sessionLogData)
err := pogs.Extract(p, SessionLog_TypeID, s.Struct)
return p, err
}