From 717518cb5f55ef0f091cdad84614a4facaeb3dd8 Mon Sep 17 00:00:00 2001
From: Hellojack <106379370+H1JK@users.noreply.github.com>
Date: Mon, 9 Jan 2023 19:14:03 +0800
Subject: [PATCH] Refine the logic of security type AUTO (#1509)

---
 common/protocol/headers.go | 16 +++++++++++++++-
 1 file changed, 15 insertions(+), 1 deletion(-)

diff --git a/common/protocol/headers.go b/common/protocol/headers.go
index 1dcc467e..8806ee80 100644
--- a/common/protocol/headers.go
+++ b/common/protocol/headers.go
@@ -3,6 +3,8 @@ package protocol
 import (
 	"runtime"
 
+	"golang.org/x/sys/cpu"
+
 	"github.com/xtls/xray-core/common/bitmask"
 	"github.com/xtls/xray-core/common/net"
 	"github.com/xtls/xray-core/common/uuid"
@@ -79,9 +81,21 @@ type CommandSwitchAccount struct {
 	ValidMin byte
 }
 
+var (
+	hasGCMAsmAMD64 = cpu.X86.HasAES && cpu.X86.HasPCLMULQDQ
+	hasGCMAsmARM64 = cpu.ARM64.HasAES && cpu.ARM64.HasPMULL
+	// Keep in sync with crypto/aes/cipher_s390x.go.
+	hasGCMAsmS390X = cpu.S390X.HasAES && cpu.S390X.HasAESCBC && cpu.S390X.HasAESCTR &&
+		(cpu.S390X.HasGHASH || cpu.S390X.HasAESGCM)
+
+	hasAESGCMHardwareSupport = runtime.GOARCH == "amd64" && hasGCMAsmAMD64 ||
+		runtime.GOARCH == "arm64" && hasGCMAsmARM64 ||
+		runtime.GOARCH == "s390x" && hasGCMAsmS390X
+)
+
 func (sc *SecurityConfig) GetSecurityType() SecurityType {
 	if sc == nil || sc.Type == SecurityType_AUTO {
-		if runtime.GOARCH == "amd64" || runtime.GOARCH == "s390x" || runtime.GOARCH == "arm64" {
+		if hasAESGCMHardwareSupport {
 			return SecurityType_AES128_GCM
 		}
 		return SecurityType_CHACHA20_POLY1305