feat: native Hysteria2 Gecko obfs (drop the sidecar)

app/src/main/java/io/nekohasekai/sagernet/fmt/hysteria/HysteriaFmt.kt

@@ -294,9 +294,8 @@ fun getFirstPort(portStr: String): Int {
 
 fun HysteriaBean.canUseSingBox(): Boolean {
     if (protocol != HysteriaBean.PROTOCOL_UDP) return false
-    // The starifly sing-box core only supports Salamander obfs. Gecko obfs is provided by
-    // the bundled official hysteria binary sidecar, so force the external path for Gecko.
-    if (protocolVersion == 2 && hysteria2ObfsType == HysteriaBean.OBFS_GECKO) return false
+    // Gecko obfs is now supported natively by this fork's sing-box core (via the
+    // hawkff/sing-quic gecko backport), so it no longer needs the sidecar.
     return true
 }
 
@@ -354,11 +353,24 @@ fun buildSingBoxOutboundHysteriaBean(bean: HysteriaBean): SingBoxOptions.SingBox
             up_mbps = bean.uploadMbps
             down_mbps = bean.downloadMbps
             if (bean.obfuscation.isNotBlank() && bean.hysteria2ObfsType != HysteriaBean.OBFS_NONE) {
-                // Native sing-box core only supports Salamander; Gecko goes through the
-                // bundled hysteria binary sidecar (canUseSingBox() == false for Gecko).
                 obfs = SingBoxOptions.Hysteria2Obfs().apply {
-                    type = "salamander"
-                    password = bean.obfuscation
+                    when (bean.hysteria2ObfsType) {
+                        HysteriaBean.OBFS_GECKO -> {
+                            type = "gecko"
+                            password = bean.obfuscation
+                            if (bean.geckoMinPacketSize != null && bean.geckoMinPacketSize > 0) {
+                                min_packet_size = bean.geckoMinPacketSize
+                            }
+                            if (bean.geckoMaxPacketSize != null && bean.geckoMaxPacketSize > 0) {
+                                max_packet_size = bean.geckoMaxPacketSize
+                            }
+                        }
+
+                        else -> {
+                            type = "salamander"
+                            password = bean.obfuscation
+                        }
+                    }
                 }
             }
 //            disable_mtu_discovery = bean.disableMtuDiscovery

app/src/main/java/moe/matsuri/nb4a/SingBoxOptions.java

@@ -646,6 +646,11 @@ public static class Hysteria2Obfs extends SingBoxOption {
 
         public String password;
 
+        // Gecko obfs only (flattened into the obfs object by the core's badjson serializer).
+        public Integer min_packet_size;
+
+        public Integer max_packet_size;
+
     }
 
     public static class Hysteria2User extends SingBoxOption {

buildScript/lib/core/get_source_env.sh

@@ -1,2 +1,2 @@
-export COMMIT_SING_BOX="ed45ea96fa27d27bd346539403303c8384b7d210"
+export COMMIT_SING_BOX="d003dccf165816f51b669ded6d2d4e66df5c3b3b"
 export COMMIT_LIBNEKO="1c47a3af71990a7b2192e03292b4d246c308ef0b"

libcore/go.mod

@@ -1,8 +1,6 @@
 module libcore
 
-go 1.24.7
-
-toolchain go1.26.4
+go 1.26.4
 
 require (
 	github.com/dyhkwong/sing-juicity v0.0.3
@@ -107,3 +105,5 @@ replace github.com/sagernet/sing-vmess => github.com/starifly/sing-vmess v0.2.8-
 // replace github.com/sagernet/sing-dns => ../../sing-dns
 
 // replace berty.tech/go-libtor => github.com/berty/go-libtor v0.0.0-20220627102132-9189eb6e3982
+
+replace github.com/sagernet/sing-quic => github.com/hawkff/sing-quic v0.5.3-0.20260618035506-f2f558c5aaba

libcore/go.sum

@@ -95,6 +95,8 @@ github.com/gorilla/csrf v1.7.3-0.20250123201450-9dd6af1f6d30/go.mod h1:F1Fj3KG23
 github.com/gorilla/securecookie v1.1.2/go.mod h1:NfCASbcHqRSY+3a8tlWJwsQap2VX5pwzwo4h3eOamfo=
 github.com/hashicorp/yamux v0.1.2 h1:XtB8kyFOyHXYVFnwT5C3+Bdo8gArse7j2AQ0DA0Uey8=
 github.com/hashicorp/yamux v0.1.2/go.mod h1:C+zze2n6e/7wshOZep2A70/aQU6QBRWJO/G6FT1wIns=
+github.com/hawkff/sing-quic v0.5.3-0.20260618035506-f2f558c5aaba h1:r2nlyrd4MBY8OPS4wEOw8SojAdnyzzl81OEKD4CES60=
+github.com/hawkff/sing-quic v0.5.3-0.20260618035506-f2f558c5aaba/go.mod h1:evP1e++ZG8TJHVV5HudXV4vWeYzGfCdF4HwSJZcdqkI=
 github.com/hdevalence/ed25519consensus v0.2.0/go.mod h1:w3BHWjwJbFU29IRHL1Iqkw3sus+7FctEyM4RqDxYNzo=
 github.com/illarion/gonotify/v2 v2.0.3/go.mod h1:38oIJTgFqupkEydkkClkbL6i5lXV/bxdH9do5TALPEE=
 github.com/inconshreveable/mousetrap v1.1.0/go.mod h1:vpF70FUmC8bwa3OWnCshd2FqLfsEA9PFc4w1p2J65bw=
@@ -200,8 +202,6 @@ github.com/sagernet/sing v0.7.18 h1:iZHkaru1/MoHugx3G+9S3WG4owMewKO/KvieE2Pzk4E=
 github.com/sagernet/sing v0.7.18/go.mod h1:ARkL0gM13/Iv5VCZmci/NuoOlePoIsW0m7BWfln/Hak=
 github.com/sagernet/sing-mux v0.3.4 h1:ZQplKl8MNXutjzbMVtWvWG31fohhgOfCuUZR4dVQ8+s=
 github.com/sagernet/sing-mux v0.3.4/go.mod h1:QvlKMyNBNrQoyX4x+gq028uPbLM2XeRpWtDsWBJbFSk=
-github.com/sagernet/sing-quic v0.5.2 h1:I3vlfRImhr0uLwRS3b3ib70RMG9FcXtOKKUDz3eKRWc=
-github.com/sagernet/sing-quic v0.5.2/go.mod h1:evP1e++ZG8TJHVV5HudXV4vWeYzGfCdF4HwSJZcdqkI=
 github.com/sagernet/sing-shadowsocks v0.2.8 h1:PURj5PRoAkqeHh2ZW205RWzN9E9RtKCVCzByXruQWfE=
 github.com/sagernet/sing-shadowsocks v0.2.8/go.mod h1:lo7TWEMDcN5/h5B8S0ew+r78ZODn6SwVaFhvB6H+PTI=
 github.com/sagernet/sing-shadowsocks2 v0.2.1 h1:dWV9OXCeFPuYGHb6IRqlSptVnSzOelnqqs2gQ2/Qioo=