Add dial option `bind_address_no_port`

common/dialer/default.go

@@ -137,6 +137,12 @@ func NewDefault(ctx context.Context, options option.DialerOptions) (*DefaultDial
 		dialer.Control = control.Append(dialer.Control, control.ProtectPath(options.ProtectPath))
 		listener.Control = control.Append(listener.Control, control.ProtectPath(options.ProtectPath))
 	}
+	if options.BindAddressNoPort {
+		if !C.IsLinux {
+			return nil, E.New("`bind_address_no_port` is only supported on Linux")
+		}
+		dialer.Control = control.Append(dialer.Control, control.BindAddressNoPort())
+	}
 	if options.ConnectTimeout != 0 {
 		dialer.Timeout = time.Duration(options.ConnectTimeout)
 	} else {

docs/configuration/shared/dial.md

@@ -6,7 +6,8 @@ icon: material/new-box
 
     :material-plus: [disable_tcp_keep_alive](#disable_tcp_keep_alive)  
     :material-plus: [tcp_keep_alive](#tcp_keep_alive)  
-    :material-plus: [tcp_keep_alive_interval](#tcp_keep_alive_interval)
+    :material-plus: [tcp_keep_alive_interval](#tcp_keep_alive_interval)  
+    :material-plus: [bind_address_no_port](#bind_address_no_port)
 
 !!! quote "Changes in sing-box 1.12.0"
 
@@ -29,6 +30,7 @@ icon: material/new-box
   "bind_interface": "",
   "inet4_bind_address": "",
   "inet6_bind_address": "",
+  "bind_address_no_port": false,
   "routing_mark": 0,
   "reuse_addr": false,
   "netns": "",
@@ -76,6 +78,18 @@ The IPv4 address to bind to.
 
 The IPv6 address to bind to.
 
+#### bind_address_no_port
+
+!!! question "Since sing-box 1.13.0"
+
+!!! quote ""
+
+    Only supported on Linux.
+
+Do not reserve a port when binding to a source address.
+
+This allows reusing the same source port for multiple connections if the full 4-tuple (source IP, source port, destination IP, destination port) remains unique.
+
 #### routing_mark
 
 !!! quote ""

docs/configuration/shared/dial.zh.md

@@ -6,7 +6,8 @@ icon: material/new-box
 
     :material-plus: [disable_tcp_keep_alive](#disable_tcp_keep_alive)  
     :material-plus: [tcp_keep_alive](#tcp_keep_alive)  
-    :material-plus: [tcp_keep_alive_interval](#tcp_keep_alive_interval)
+    :material-plus: [tcp_keep_alive_interval](#tcp_keep_alive_interval)  
+    :material-plus: [bind_address_no_port](#bind_address_no_port)
 
 !!! quote "sing-box 1.12.0 中的更改"
 
@@ -29,6 +30,7 @@ icon: material/new-box
   "bind_interface": "",
   "inet4_bind_address": "",
   "inet6_bind_address": "",
+  "bind_address_no_port": false,
   "routing_mark": 0,
   "reuse_addr": false,
   "netns": "",
@@ -76,6 +78,18 @@ icon: material/new-box
 
 要绑定的 IPv6 地址。
 
+#### bind_address_no_port
+
+!!! question "自 sing-box 1.13.0 起"
+
+!!! quote ""
+
+    仅支持 Linux。
+
+绑定到源地址时不保留端口。
+
+这允许在完整的四元组（源 IP、源端口、目标 IP、目标端口）保持唯一的情况下，为多个连接复用同一源端口。
+
 #### routing_mark
 
 !!! quote ""

go.mod

@@ -32,7 +32,7 @@ require (
 	github.com/sagernet/gomobile v0.1.11
 	github.com/sagernet/gvisor v0.0.0-20250811.0-sing-box-mod.1
 	github.com/sagernet/quic-go v0.58.0-sing-box-mod.1
-	github.com/sagernet/sing v0.8.0-beta.9
+	github.com/sagernet/sing v0.8.0-beta.9.0.20260109141034-50e1ed36c6f6
 	github.com/sagernet/sing-mux v0.3.4
 	github.com/sagernet/sing-quic v0.6.0-beta.8
 	github.com/sagernet/sing-shadowsocks v0.2.8

go.sum

@@ -208,8 +208,8 @@ github.com/sagernet/nftables v0.3.0-beta.4 h1:kbULlAwAC3jvdGAC1P5Fa3GSxVwQJibNen
 github.com/sagernet/nftables v0.3.0-beta.4/go.mod h1:OQXAjvjNGGFxaTgVCSTRIhYB5/llyVDeapVoENYBDS8=
 github.com/sagernet/quic-go v0.58.0-sing-box-mod.1 h1:E9yZrU0ZxSiW5RrGUnFZeI02EIMdAAv0RxdoxXCqZyk=
 github.com/sagernet/quic-go v0.58.0-sing-box-mod.1/go.mod h1:OqILvS182CyOol5zNNo6bguvOGgXzV459+chpRaUC+4=
-github.com/sagernet/sing v0.8.0-beta.9 h1:LTFjTYiEr6A5NZ04tbrjWLb0T7unSmEJX2ksJkfI1lY=
-github.com/sagernet/sing v0.8.0-beta.9/go.mod h1:ARkL0gM13/Iv5VCZmci/NuoOlePoIsW0m7BWfln/Hak=
+github.com/sagernet/sing v0.8.0-beta.9.0.20260109141034-50e1ed36c6f6 h1:TgmW2IKThK+3wWhoB/UKjwdW2NUyWqCyXZoCYTMizv8=
+github.com/sagernet/sing v0.8.0-beta.9.0.20260109141034-50e1ed36c6f6/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 v0.6.0-beta.8 h1:Y0P8WTqWpfg80rLFsDfF22QumM+HEAjRQ2o+8Dv+vDs=

option/outbound.go

@@ -69,6 +69,7 @@ type DialerOptions struct {
 	BindInterface        string                            `json:"bind_interface,omitempty"`
 	Inet4BindAddress     *badoption.Addr                   `json:"inet4_bind_address,omitempty"`
 	Inet6BindAddress     *badoption.Addr                   `json:"inet6_bind_address,omitempty"`
+	BindAddressNoPort    bool                              `json:"bind_address_no_port,omitempty"`
 	ProtectPath          string                            `json:"protect_path,omitempty"`
 	RoutingMark          FwMark                            `json:"routing_mark,omitempty"`
 	ReuseAddr            bool                              `json:"reuse_addr,omitempty"`