diff --git a/main/confloader/confloader.go b/main/confloader/confloader.go
new file mode 100644
index 000000000..f9dd9223d
--- /dev/null
+++ b/main/confloader/confloader.go
@@ -0,0 +1,21 @@
+package confloader
+
+import (
+	"io"
+	"os"
+)
+
+//go:generate go run $GOPATH/src/v2ray.com/core/common/errors/errorgen/main.go -pkg confloader -path Main,ConfLoader
+
+type configFileLoader func(string) (io.ReadCloser, error)
+
+var (
+	EffectiveConfigFileLoader configFileLoader
+)
+
+func LoadConfig(file string) (io.ReadCloser, error) {
+	if EffectiveConfigFileLoader == nil {
+		return os.Stdin, nil
+	}
+	return EffectiveConfigFileLoader(file)
+}
diff --git a/main/confloader/errors.generated.go b/main/confloader/errors.generated.go
new file mode 100644
index 000000000..41fb556ca
--- /dev/null
+++ b/main/confloader/errors.generated.go
@@ -0,0 +1,5 @@
+package confloader
+
+import "v2ray.com/core/common/errors"
+
+func newError(values ...interface{}) *errors.Error { return errors.New(values...).Path("Main", "ConfLoader") }
diff --git a/main/confloader/external/errors.generated.go b/main/confloader/external/errors.generated.go
new file mode 100644
index 000000000..0c85ab53c
--- /dev/null
+++ b/main/confloader/external/errors.generated.go
@@ -0,0 +1,5 @@
+package external
+
+import "v2ray.com/core/common/errors"
+
+func newError(values ...interface{}) *errors.Error { return errors.New(values...).Path("Main", "ConfLoader", "External") }
diff --git a/main/confloader/external/external.go b/main/confloader/external/external.go
new file mode 100644
index 000000000..21cc709a2
--- /dev/null
+++ b/main/confloader/external/external.go
@@ -0,0 +1,54 @@
+package external
+
+import (
+	"io"
+	"os"
+	"strings"
+
+	"v2ray.com/core/common/buf"
+	"v2ray.com/core/common/platform/ctlcmd"
+	"v2ray.com/core/main/confloader"
+)
+
+//go:generate go run $GOPATH/src/v2ray.com/core/common/errors/errorgen/main.go -pkg external -path Main,ConfLoader,External
+
+type ClosableMultiBuffer struct {
+	buf.MultiBuffer
+}
+
+func (c *ClosableMultiBuffer) Close() error {
+	c.MultiBuffer.Release()
+	return nil
+}
+
+func loadConfigFile(configFile string) (io.ReadCloser, error) {
+	if configFile == "stdin:" {
+		return os.Stdin, nil
+	}
+
+	if strings.HasPrefix(configFile, "http://") || strings.HasPrefix(configFile, "https://") {
+		content, err := ctlcmd.Run([]string{"fetch", configFile}, nil)
+		if err != nil {
+			return nil, err
+		}
+		return &ClosableMultiBuffer{content}, nil
+	}
+
+	fixedFile := os.ExpandEnv(configFile)
+	file, err := os.Open(fixedFile)
+	if err != nil {
+		return nil, newError("config file not readable").Base(err)
+	}
+	defer file.Close()
+
+	content, err := buf.ReadAllToMultiBuffer(file)
+	if err != nil {
+		return nil, newError("failed to load config file: ", fixedFile).Base(err).AtWarning()
+	}
+	return &ClosableMultiBuffer{content}, nil
+
+}
+
+func init() {
+	confloader.EffectiveConfigFileLoader = loadConfigFile
+}
diff --git a/main/distro/all/all.go b/main/distro/all/all.go
index 989d7c2e0..486c5be8b 100644
--- a/main/distro/all/all.go
+++ b/main/distro/all/all.go
@@ -48,4 +48,7 @@ import (
 
 	// JSON config format
 	_ "v2ray.com/core/main/json"
+
+	// Load config from file or http(s)
+	_ "v2ray.com/core/main/confloader/external"
 )
diff --git a/main/main.go b/main/main.go
index 55b293d08..6179b676a 100644
--- a/main/main.go
+++ b/main/main.go
@@ -5,7 +5,6 @@ package main
 import (
 	"flag"
 	"fmt"
-	"io"
 	"os"
 	"os/signal"
 	"path/filepath"
@@ -14,7 +13,7 @@ import (
 
 	"v2ray.com/core"
 	"v2ray.com/core/common/platform"
-	"v2ray.com/core/common/platform/ctlcmd"
+	"v2ray.com/core/main/confloader"
 	_ "v2ray.com/core/main/distro/all"
 )
 
@@ -61,24 +60,12 @@ func GetConfigFormat() string {
 
 func startV2Ray() (core.Server, error) {
 	configFile := getConfigFilePath()
-	var configInput io.Reader
-	if configFile == "stdin:" {
-		configInput = os.Stdin
-	} else if strings.HasPrefix(configFile, "http://") || strings.HasPrefix(configFile, "https://") {
-		content, err := ctlcmd.Run([]string{"fetch", configFile}, nil)
-		if err != nil {
-			return nil, err
-		}
-		configInput = &content
-	} else {
-		fixedFile := os.ExpandEnv(configFile)
-		file, err := os.Open(fixedFile)
-		if err != nil {
-			return nil, newError("config file not readable").Base(err)
-		}
-		defer file.Close()
-		configInput = file
+	configInput, err := confloader.LoadConfig(configFile)
+	if err != nil {
+		return nil, newError("failed to load config: ", configFile).Base(err)
 	}
+	defer configInput.Close()
+
 	config, err := core.LoadConfig(GetConfigFormat(), configFile, configInput)
 	if err != nil {
 		return nil, newError("failed to read config file: ", configFile).Base(err)