Add concurrency parameter

config/config.go

@@ -10,13 +10,14 @@ import (
 )
 
 type Config struct {
-	Debug     bool          `json:"debug"`
-	Secret    mtglib.Secret `json:"secret"`
-	BindTo    TypeHostPort  `json:"bind-to"`
-	TCPBuffer TypeBytes     `json:"tcp-buffer"`
-	PreferIP  TypePreferIP  `json:"prefer-ip"`
-	CloakPort TypePort      `json:"cloak-port"`
-	Defense   struct {
+	Debug       bool          `json:"debug"`
+	Secret      mtglib.Secret `json:"secret"`
+	BindTo      TypeHostPort  `json:"bind-to"`
+	TCPBuffer   TypeBytes     `json:"tcp-buffer"`
+	PreferIP    TypePreferIP  `json:"prefer-ip"`
+	CloakPort   TypePort      `json:"cloak-port"`
+	Concurrency uint          `json:"concurrency"`
+	Defense     struct {
 		Time struct {
 			Enabled       bool         `json:"enabled"`
 			AllowSkewness TypeDuration `json:"allow-skewness"`
@@ -80,13 +81,14 @@ func (c *Config) String() string {
 }
 
 type configRaw struct {
-	Debug     bool   `toml:"debug" json:"debug,omitempty"`
-	Secret    string `toml:"secret" json:"secret"`
-	BindTo    string `toml:"bind-to" json:"bind-to"`
-	TCPBuffer string `toml:"tcp-buffer" json:"tcp-buffer,omitempty"`
-	PreferIP  string `toml:"prefer-ip" json:"prefer-ip,omitempty"`
-	CloakPort uint   `toml:"cloak-port" json:"cloak-port,omitempty"`
-	Defense   struct {
+	Debug       bool   `toml:"debug" json:"debug,omitempty"`
+	Secret      string `toml:"secret" json:"secret"`
+	BindTo      string `toml:"bind-to" json:"bind-to"`
+	TCPBuffer   string `toml:"tcp-buffer" json:"tcp-buffer,omitempty"`
+	PreferIP    string `toml:"prefer-ip" json:"prefer-ip,omitempty"`
+	CloakPort   uint   `toml:"cloak-port" json:"cloak-port,omitempty"`
+	Concurrency uint   `toml:"concurrency" json:"concurrency,omitempty"`
+	Defense     struct {
 		Time struct {
 			Enabled       bool   `toml:"enabled" json:"enabled,omitempty"`
 			AllowSkewness string `toml:"allow-skewness" json:"allow-skewness,omitempty"`

example.config.toml

@@ -23,6 +23,10 @@ secret = "ee367a189aee18fa31c190054efd4a8e9573746f726167652e676f6f676c6561706973
 # Host:port pair to run proxy on.
 bind-to = "0.0.0.0:3128"
 
+# Defines how many concurrent connections are allowed to this proxy.
+# All other incoming connections are going to be dropped.
+concurrency = 8192
+
 # A size of user-space buffer for TCP to use. Since we do 2 connections,
 # then we have tcp-buffer * (4 + 2) per each connection: read/write for
 # each connection + 2 copy buffers to pump the data between sockets.