install go2rtc on bob

installs_on_host/go2rtc/pkg/tcp/websocket/dial.go

@@ -0,0 +1,65 @@
+package websocket
+
+import (
+	cryptorand "crypto/rand"
+	"crypto/sha1"
+	"encoding/base64"
+	"errors"
+	"net"
+	"net/http"
+	"strings"
+
+	"github.com/AlexxIT/go2rtc/pkg/tcp"
+)
+
+func Dial(address string) (net.Conn, error) {
+	if strings.HasPrefix(address, "ws") {
+		address = "http" + address[2:] // support http and https
+	}
+
+	// using custom client for support Digest Auth
+	// https://github.com/AlexxIT/go2rtc/issues/415
+	ctx, pconn := tcp.WithConn()
+
+	req, err := http.NewRequestWithContext(ctx, "GET", address, nil)
+	if err != nil {
+		return nil, err
+	}
+
+	key, accept := GetKeyAccept()
+
+	// Version, Key, Protocol important for Axis cameras
+	req.Header.Set("Connection", "Upgrade")
+	req.Header.Set("Upgrade", "websocket")
+	req.Header.Set("Sec-WebSocket-Version", "13")
+	req.Header.Set("Sec-WebSocket-Key", key)
+	req.Header.Set("Sec-WebSocket-Protocol", "binary")
+
+	res, err := tcp.Do(req)
+	if err != nil {
+		return nil, err
+	}
+
+	if res.StatusCode != http.StatusSwitchingProtocols {
+		return nil, errors.New("wrong status: " + res.Status)
+	}
+
+	if res.Header.Get("Sec-Websocket-Accept") != accept {
+		return nil, errors.New("wrong websocket accept")
+	}
+
+	return NewClient(*pconn), nil
+}
+
+func GetKeyAccept() (key, accept string) {
+	b := make([]byte, 16)
+	_, _ = cryptorand.Read(b)
+	key = base64.StdEncoding.EncodeToString(b)
+
+	h := sha1.New()
+	h.Write([]byte(key))
+	h.Write([]byte("258EAFA5-E914-47DA-95CA-C5AB0DC85B11"))
+	accept = base64.StdEncoding.EncodeToString(h.Sum(nil))
+
+	return
+}