hysteria: also accept "hysteria2" protocol string

UI stores v1 and v2 both as "hysteria" with settings.version, but
inbounds that came in from imports / manual SQL can carry the
literal "hysteria2" string and get silently dropped everywhere we
switch on protocol.

Add Hysteria2 constant + IsHysteria helper, use it in the places
that gate on protocol (sub SQL, getLink, genHysteriaLink, clash
buildProxy, json gen, inbound.go validation, xray AddUser).

Existing "hysteria" inbounds are untouched.

closes #4081

3 files changed, 11 insertions, 12 deletions

diff --git a/sub/subClashService.go b/sub/subClashService.go
index d0445aa4..7b6b8214 100644
--- a/sub/subClashService.go
+++ b/sub/subClashService.go
@@ -159,13 +159,10 @@ func (s *SubClashService) getProxies(inbound *model.Inbound, client model.Client
 }
 
 func (s *SubClashService) buildProxy(inbound *model.Inbound, client model.Client, stream map[string]any, extraRemark string) map[string]any {
-	// Hysteria (v1 / v2) doesn't ride an xray `streamSettings.network`
-	// transport and the TLS story is handled inside hysteria itself, so
-	// applyTransport / applySecurity below don't model it. Build the
-	// proxy directly. Without this, hysteria inbounds fell into the
-	// `default: return nil` branch and silently vanished from the
-	// generated Clash config.
-	if inbound.Protocol == model.Hysteria {
+	// Hysteria has its own transport + TLS model, applyTransport /
+	// applySecurity don't fit. IsHysteria also covers the literal
+	// "hysteria2" protocol string (#4081).
+	if model.IsHysteria(inbound.Protocol) {
 		return s.buildHysteriaProxy(inbound, client, extraRemark)
 	}
 
diff --git a/sub/subJsonService.go b/sub/subJsonService.go
index acb8e05f..a51f10bb 100644
--- a/sub/subJsonService.go
+++ b/sub/subJsonService.go
@@ -209,7 +209,7 @@ func (s *SubJsonService) getConfig(inbound *model.Inbound, client model.Client,
 			newOutbounds = append(newOutbounds, s.genVless(inbound, streamSettings, client))
 		case "trojan", "shadowsocks":
 			newOutbounds = append(newOutbounds, s.genServer(inbound, streamSettings, client))
-		case "hysteria":
+		case "hysteria", "hysteria2":
 			newOutbounds = append(newOutbounds, s.genHy(inbound, newStream, client))
 		}
 
diff --git a/sub/subService.go b/sub/subService.go
index dd6bbcc9..44549390 100644
--- a/sub/subService.go
+++ b/sub/subService.go
@@ -115,12 +115,14 @@ func (s *SubService) GetSubs(subId string, host string) ([]string, int64, xray.C
 func (s *SubService) getInboundsBySubId(subId string) ([]*model.Inbound, error) {
 	db := database.GetDB()
 	var inbounds []*model.Inbound
+	// allow "hysteria2" so imports stored with the literal v2 protocol
+	// string still surface here (#4081)
 	err := db.Model(model.Inbound{}).Preload("ClientStats").Where(`id in (
 		SELECT DISTINCT inbounds.id
 		FROM inbounds,
-			JSON_EACH(JSON_EXTRACT(inbounds.settings, '$.clients')) AS client 
+			JSON_EACH(JSON_EXTRACT(inbounds.settings, '$.clients')) AS client
 		WHERE
-			protocol in ('vmess','vless','trojan','shadowsocks','hysteria')
+			protocol in ('vmess','vless','trojan','shadowsocks','hysteria','hysteria2')
 			AND JSON_EXTRACT(client.value, '$.subId') = ? AND enable = ?
 	)`, subId, true).Find(&inbounds).Error
 	if err != nil {
@@ -171,7 +173,7 @@ func (s *SubService) getLink(inbound *model.Inbound, email string) string {
 		return s.genTrojanLink(inbound, email)
 	case "shadowsocks":
 		return s.genShadowsocksLink(inbound, email)
-	case "hysteria":
+	case "hysteria", "hysteria2":
 		return s.genHysteriaLink(inbound, email)
 	}
 	return ""
@@ -906,7 +908,7 @@ func (s *SubService) genShadowsocksLink(inbound *model.Inbound, email string) st
 }
 
 func (s *SubService) genHysteriaLink(inbound *model.Inbound, email string) string {
-	if inbound.Protocol != model.Hysteria {
+	if !model.IsHysteria(inbound.Protocol) {
 		return ""
 	}
 	var stream map[string]interface{}