From: Sergey Matveev <stargrave@stargrave.org>
Date: Fri, 17 Sep 2021 19:51:14 +0000 (+0300)
Subject: Buffer fixing and simplification
X-Git-Tag: v0.1.0~7
X-Git-Url: http://www.git.cypherpunks.ru/?p=ucspi.git;a=commitdiff_plain;h=72fc7e6d14a5113b013514eecd3c5b3485671631

Buffer fixing and simplification
---

diff --git a/cmd/tlsc/main.go b/cmd/tlsc/main.go
index 7f1651a..aa1d142 100644
--- a/cmd/tlsc/main.go
+++ b/cmd/tlsc/main.go
@@ -102,12 +102,9 @@ func main() {
 		}
 	}
 
-	conn := &ucspi.Conn{R: os.NewFile(6, "R"), W: os.NewFile(7, "W")}
-	if conn.R == nil {
-		log.Fatalln("no 6 file descriptor")
-	}
-	if conn.W == nil {
-		log.Fatalln("no 7 file descriptor")
+	conn, err := ucspi.NewConn(os.NewFile(6, "R"), os.NewFile(7, "W"))
+	if err != nil {
+		log.Fatalln(err)
 	}
 	tlsConn := tls.Client(conn, cfg)
 	if err := tlsConn.Handshake(); err != nil {
@@ -154,17 +151,18 @@ func main() {
 	if err = cmd.Start(); err != nil {
 		log.Fatalln(err)
 	}
-	copiers := make(chan struct{})
+	worker := make(chan struct{})
 	go func() {
 		io.Copy(rw, tlsConn)
 		rw.Close()
-		close(copiers)
+		close(worker)
 	}()
 	go func() {
 		io.Copy(tlsConn, wr)
 	}()
 	_, err = cmd.Process.Wait()
-	<-copiers
+	<-worker
+	tlsConn.Close()
 	if err != nil {
 		log.Fatalln(err)
 	}
diff --git a/cmd/tlss/main.go b/cmd/tlss/main.go
index 7740ecd..881d221 100644
--- a/cmd/tlss/main.go
+++ b/cmd/tlss/main.go
@@ -22,6 +22,7 @@ import (
 	"crypto/x509"
 	"flag"
 	"fmt"
+	"io"
 	"log"
 	"os"
 	"os/exec"
@@ -70,7 +71,7 @@ func main() {
 		cfg.ClientAuth = tls.RequireAndVerifyClientCert
 	}
 
-	conn := &ucspi.Conn{R: os.Stdin, W: os.Stdout}
+	conn, _ := ucspi.NewConn(os.Stdin, os.Stdout)
 	tlsConn := tls.Server(conn, cfg)
 	if err = tlsConn.Handshake(); err != nil {
 		log.Fatalln(err)
@@ -80,10 +81,18 @@ func main() {
 		dn = tlsConn.ConnectionState().PeerCertificates[0].Subject.String()
 	}
 
+	rr, rw, err := os.Pipe()
+	if err != nil {
+		log.Fatalln(err)
+	}
+	wr, ww, err := os.Pipe()
+	if err != nil {
+		log.Fatalln(err)
+	}
 	args := flag.Args()
 	cmd := exec.Command(args[0], args[1:]...)
-	cmd.Stdin = tlsConn
-	cmd.Stdout = tlsConn
+	cmd.Stdin = rr
+	cmd.Stdout = ww
 	cmd.Stderr = os.Stderr
 	cmd.Env = append(os.Environ(), "PROTO=TLS")
 	if dn != "" {
@@ -93,7 +102,19 @@ func main() {
 	if err = cmd.Start(); err != nil {
 		log.Fatalln(err)
 	}
-	if _, err = cmd.Process.Wait(); err != nil {
+	worker := make(chan struct{})
+	go func() {
+		io.Copy(rw, tlsConn)
+	}()
+	go func() {
+		io.Copy(tlsConn, wr)
+		tlsConn.Close()
+		close(worker)
+	}()
+	err = cmd.Wait()
+	ww.Close()
+	<-worker
+	if err != nil {
 		log.Fatalln(err)
 	}
 }
diff --git a/conn.go b/conn.go
index 7a6ac42..480a298 100644
--- a/conn.go
+++ b/conn.go
@@ -18,7 +18,7 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 package ucspi
 
 import (
-	"io"
+	"errors"
 	"net"
 	"os"
 	"time"
@@ -36,37 +36,33 @@ func (addr *Addr) Network() string { return "tcp" }
 func (addr *Addr) String() string { return addr.ip + ":" + addr.port }
 
 type Conn struct {
-	R   *os.File
-	W   *os.File
-	eof chan struct{}
+	R *os.File
+	W *os.File
 }
 
-type ReadResult struct {
-	n   int
-	err error
+func NewConn(r, w *os.File) (*Conn, error) {
+	if r == nil {
+		return nil, errors.New("no R file descriptor")
+	}
+	if w == nil {
+		return nil, errors.New("no W file descriptor")
+	}
+	return &Conn{R: r, W: w}, nil
 }
 
 func (conn *Conn) Read(b []byte) (int, error) {
-	c := make(chan ReadResult)
-	go func() {
-		n, err := conn.R.Read(b)
-		c <- ReadResult{n, err}
-	}()
-	select {
-	case res := <-c:
-		return res.n, res.err
-	case <-conn.eof:
-		return 0, io.EOF
-	}
+	return conn.R.Read(b)
 }
 
 func (conn *Conn) Write(b []byte) (int, error) { return conn.W.Write(b) }
 
 func (conn *Conn) Close() error {
-	if err := conn.R.Close(); err != nil {
-		return err
+	errR := conn.R.Close()
+	errW := conn.W.Close()
+	if errR != nil {
+		return errR
 	}
-	return os.Stdin.Close()
+	return errW
 }
 
 func (conn *Conn) LocalAddr() net.Addr {
@@ -85,12 +81,6 @@ func (conn *Conn) SetDeadline(t time.Time) error {
 }
 
 func (conn *Conn) SetReadDeadline(t time.Time) error {
-	// An ugly hack to forcefully terminate pending read.
-	// net/http calls SetReadDeadline(aLongTimeAgo), but file
-	// descriptors are not capable to exit immediately that way.
-	if t.Equal(aLongTimeAgo) {
-		conn.eof <- struct{}{}
-	}
 	return conn.R.SetReadDeadline(t)
 }