Revert: undo crypto/rand

This reverts commit 4a8bf64cb1.

component/simple-obfs/http.go

@@ -2,10 +2,10 @@ package obfs
 
 import (
 	"bytes"
-	"crypto/rand"
 	"encoding/base64"
 	"fmt"
 	"io"
+	"math/rand"
 	"net"
 	"net/http"
 
@@ -65,7 +65,7 @@ func (ho *HTTPObfs) Write(b []byte) (int, error) {
 		randBytes := make([]byte, 16)
 		rand.Read(randBytes)
 		req, _ := http.NewRequest("GET", fmt.Sprintf("http://%s/", ho.host), bytes.NewBuffer(b[:]))
-		req.Header.Set("User-Agent", fmt.Sprintf("curl/7.%d.%d", randInt()%54, randInt()%2))
+		req.Header.Set("User-Agent", fmt.Sprintf("curl/7.%d.%d", rand.Int()%54, rand.Int()%2))
 		req.Header.Set("Upgrade", "websocket")
 		req.Header.Set("Connection", "Upgrade")
 		req.Host = ho.host

component/simple-obfs/obfs.go

@@ -1,15 +1,4 @@
 // Package obfs provides obfuscation functionality for Shadowsocks protocol.
 package obfs
 
-import (
-	"crypto/rand"
-	"math"
-	"math/big"
-)
-
 // Ref: github.com/Dreamacro/clash/component/simple-obfs
-
-func randInt() int {
-	n, _ := rand.Int(rand.Reader, big.NewInt(math.MaxInt))
-	return int(n.Int64())
-}

component/simple-obfs/tls.go

@@ -2,15 +2,19 @@ package obfs
 
 import (
 	"bytes"
-	"crypto/rand"
 	"encoding/binary"
 	"io"
+	"math/rand"
 	"net"
 	"time"
 
 	"github.com/xjasonlyu/tun2socks/v2/common/pool"
 )
 
+func init() {
+	rand.Seed(time.Now().Unix())
+}
+
 const (
 	chunkSize = 1 << 14 // 2 ** 14 == 16 * 1024
 )