fix: write to lConn even if io.EOF met and some bytes was read

This commit is contained in:
Andrey Semenov 2024-09-19 17:21:03 +05:00
parent a2993ac68d
commit a12a13eb4b

View File

@ -2,10 +2,14 @@ package handler
import (
"context"
"errors"
"io"
"net"
"regexp"
"strconv"
"sync"
"github.com/rs/zerolog"
"github.com/xvzc/SpoofDPI/packet"
"github.com/xvzc/SpoofDPI/util"
"github.com/xvzc/SpoofDPI/util/log"
@ -74,36 +78,53 @@ func (h *HttpsHandler) Serve(ctx context.Context, lConn *net.TCPConn, initPkt *p
logger.Debug().Msgf("client sent hello %d bytes", len(clientHello))
// Generate a go routine that reads from the server
go h.communicate(ctx, rConn, lConn, initPkt.Domain(), lConn.RemoteAddr().String())
go h.communicate(ctx, lConn, rConn, lConn.RemoteAddr().String(), initPkt.Domain())
closeWg := sync.WaitGroup{}
closeWg.Add(2)
done := make(chan struct{})
doneOnce := sync.Once{}
closeDoneFunc := func() {
close(done)
}
go func() {
defer closeWg.Done()
h.communicate(ctx, rConn, lConn, initPkt.Domain(), lConn.RemoteAddr().String())
}()
go func() {
defer closeWg.Done()
h.communicate(ctx, lConn, rConn, lConn.RemoteAddr().String(), initPkt.Domain())
}()
go func(wg *sync.WaitGroup) {
wg.Wait()
doneOnce.Do(closeDoneFunc)
}(&closeWg)
if h.exploit {
logger.Debug().Msgf("writing chunked client hello to %s", initPkt.Domain())
chunks := splitInChunks(ctx, clientHello, h.windowsize)
if _, err := writeChunks(rConn, chunks); err != nil {
logger.Debug().Msgf("error writing chunked client hello to %s: %s", initPkt.Domain(), err)
return
doneOnce.Do(closeDoneFunc)
}
} else {
logger.Debug().Msgf("writing plain client hello to %s", initPkt.Domain())
if _, err := rConn.Write(clientHello); err != nil {
logger.Debug().Msgf("error writing plain client hello to %s: %s", initPkt.Domain(), err)
return
doneOnce.Do(closeDoneFunc)
}
}
// wait while conn handling routines stop, then close both connections
// current routine will sleep until conn handling routines works
<-done
_ = lConn.Close()
_ = rConn.Close()
logger.Debug().Msgf("closing proxy connection: %s -> %s", lConn.RemoteAddr(), initPkt.Domain())
}
func (h *HttpsHandler) communicate(ctx context.Context, from *net.TCPConn, to *net.TCPConn, fd string, td string) {
ctx = util.GetCtxWithScope(ctx, h.protocol)
logger := log.GetCtxLogger(ctx)
defer func() {
from.Close()
to.Close()
logger.Debug().Msgf("closing proxy connection: %s -> %s", fd, td)
}()
buf := make([]byte, h.bufferSize)
for {
err := setConnectionTimeout(from, h.timeout)
@ -113,17 +134,28 @@ func (h *HttpsHandler) communicate(ctx context.Context, from *net.TCPConn, to *n
bytesRead, err := ReadBytes(ctx, from, buf)
if err != nil {
if errors.Is(err, io.EOF) && len(bytesRead) > 0 {
h.write(logger, td, to, bytesRead)
}
logger.Debug().Msgf("error reading from %s: %s", fd, err)
return
}
if _, err := to.Write(bytesRead); err != nil {
logger.Debug().Msgf("error writing to %s", td)
if !h.write(logger, td, to, bytesRead) {
return
}
}
}
func (h *HttpsHandler) write(logger zerolog.Logger, connName string, to io.Writer, bytes []byte) (ok bool) {
ok = true
if _, err := to.Write(bytes); err != nil {
logger.Debug().Msgf("error writing to %s", connName)
ok = false
}
return
}
func splitInChunks(ctx context.Context, bytes []byte, size int) [][]byte {
logger := log.GetCtxLogger(ctx)