feat(server): add auth middleware

Dockerfile

@@ -73,7 +73,7 @@
     org.opencontainers.image.source="https://github.com/qdm12/gluetun" \
     org.opencontainers.image.title="VPN swiss-knife like client for multiple VPN providers" \
     org.opencontainers.image.description="VPN swiss-knife like client to tunnel to multiple VPN servers using OpenVPN, IPtables, DNS over TLS, Shadowsocks, an HTTP proxy and Alpine Linux"
 ENV VPN_SERVICE_PROVIDER=pia \
     VPN_TYPE=openvpn \
     # Common VPN options
     VPN_INTERFACE=tun0 \
@@ -194,6 +194,7 @@
     # Control server
     HTTP_CONTROL_SERVER_LOG=on \
     HTTP_CONTROL_SERVER_ADDRESS=":8000" \
+    HTTP_CONTROL_SERVER_AUTH_CONFIG_FILEPATH=/gluetun/auth/config.toml \
     # Server data updater
     UPDATER_PERIOD=0 \
     UPDATER_MIN_RATIO=0.8 \

cmd/gluetun/main.go

@@ -160,12 +160,14 @@ func _main(ctx context.Context, buildInfo models.BuildInformation,
 			return cli.Update(ctx, args[2:], logger)
 		case "format-servers":
 			return cli.FormatServers(args[2:])
+		case "genkey":
+			return cli.GenKey(args[2:])
 		default:
 			return fmt.Errorf("%w: %s", errCommandUnknown, args[1])
 		}
 	}
 
-	announcementExp, err := time.Parse(time.RFC3339, "2023-07-01T00:00:00Z")
+	announcementExp, err := time.Parse(time.RFC3339, "2024-12-01T00:00:00Z")
 	if err != nil {
 		return err
 	}
@@ -176,7 +178,7 @@ func _main(ctx context.Context, buildInfo models.BuildInformation,
 		Version:      buildInfo.Version,
 		Commit:       buildInfo.Commit,
 		Created:      buildInfo.Created,
-		Announcement: "Wiki moved to https://github.com/qdm12/gluetun-wiki",
+		Announcement: "All control server routes will become private by default after the v3.41.0 release",
 		AnnounceExp:  announcementExp,
 		// Sponsor information
 		PaypalUser:    "qmcgaw",
@@ -465,6 +467,7 @@ func _main(ctx context.Context, buildInfo models.BuildInformation,
 		"http server", goroutine.OptionTimeout(defaultShutdownTimeout))
 	httpServer, err := server.New(httpServerCtx, controlServerAddress, controlServerLogging,
 		logger.New(log.SetComponent("http server")),
+		allSettings.ControlServer.AuthFilePath,
 		buildInfo, vpnLooper, portForwardLooper, dnsLooper, updaterLooper, publicIPLooper,
 		storage, ipv6Supported)
 	if err != nil {
@@ -586,6 +589,7 @@ type clier interface {
 	OpenvpnConfig(logger cli.OpenvpnConfigLogger, reader *reader.Reader, ipv6Checker cli.IPv6Checker) error
 	HealthCheck(ctx context.Context, reader *reader.Reader, warner cli.Warner) error
 	Update(ctx context.Context, args []string, logger cli.UpdaterLogger) error
+	GenKey(args []string) error
 }
 
 type Tun interface {

go.mod

@@ -8,6 +8,7 @@ require (
 	github.com/golang/mock v1.6.0
 	github.com/klauspost/compress v1.17.9
 	github.com/klauspost/pgzip v1.2.6
+	github.com/pelletier/go-toml/v2 v2.2.2
 	github.com/qdm12/dns/v2 v2.0.0-rc6
 	github.com/qdm12/gosettings v0.4.2
 	github.com/qdm12/goshutdown v0.3.0

go.sum

@@ -4,6 +4,7 @@ github.com/breml/rootcerts v0.2.17 h1:0/M2BE2Apw0qEJCXDOkaiu7d5Sx5ObNfe1BkImJ4u1
 github.com/breml/rootcerts v0.2.17/go.mod h1:S/PKh+4d1HUn4HQovEB8hPJZO6pUZYrIhmXBhsegfXw=
 github.com/cespare/xxhash/v2 v2.2.0 h1:DC2CZ1Ep5Y4k3ZQ899DldepgrayRUGE6BBZ/cd9Cj44=
 github.com/cespare/xxhash/v2 v2.2.0/go.mod h1:VGX0DQ3Q6kWi7AoAeZDth3/j3BFtOZR5XLFGgcrjCOs=
+github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/fatih/color v1.17.0 h1:GlRw1BRJxkpqUCBKzKOw098ed57fEsKeNjpTe3cSjK4=
@@ -47,6 +48,8 @@ github.com/miekg/dns v1.1.55 h1:GoQ4hpsj0nFLYe+bWiCToyrBEJXkQfOOIvFGFy0lEgo=
 github.com/miekg/dns v1.1.55/go.mod h1:uInx36IzPl7FYnDcMeVWxj9byh7DutNykX4G9Sj60FY=
 github.com/mikioh/ipaddr v0.0.0-20190404000644-d465c8ab6721 h1:RlZweED6sbSArvlE924+mUcZuXKLBHA35U7LN621Bws=
 github.com/mikioh/ipaddr v0.0.0-20190404000644-d465c8ab6721/go.mod h1:Ickgr2WtCLZ2MDGd4Gr0geeCH5HybhRJbonOgQpvSxc=
+github.com/pelletier/go-toml/v2 v2.2.2 h1:aYUidT7k73Pcl9nb2gScu7NSrKCSHIDE89b3+6Wq+LM=
+github.com/pelletier/go-toml/v2 v2.2.2/go.mod h1:1t835xjRzz80PqgE6HHgN2JOsmgYu/h4qDAS4n929Rs=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/prometheus/client_golang v1.16.0 h1:yk/hx9hDbrGHovbci4BY+pRMfSuuat626eFsHb7tmT8=
@@ -75,6 +78,13 @@ github.com/riobard/go-bloom v0.0.0-20200614022211-cdc8013cb5b3 h1:f/FNXud6gA3MNr
 github.com/riobard/go-bloom v0.0.0-20200614022211-cdc8013cb5b3/go.mod h1:HgjTstvQsPGkxUsCd2KWxErBblirPizecHcpD3ffK+s=
 github.com/rogpeppe/go-internal v1.11.0 h1:cWPaGQEPrBb5/AsnsZesgZZ9yb1OQ+GOISoDNXVBh4M=
 github.com/rogpeppe/go-internal v1.11.0/go.mod h1:ddIwULY96R17DhadqLgMfk9H9tvdUzkipdSkR5nkCZA=
+github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
+github.com/stretchr/objx v0.4.0/go.mod h1:YvHI0jy2hoMjB+UWwv71VJQ9isScKT/TqJzVSSt89Yw=
+github.com/stretchr/objx v0.5.0/go.mod h1:Yh+to48EsGEfYuaHDzXPcE3xhTkx73EhmCGUpEOglKo=
+github.com/stretchr/objx v0.5.2/go.mod h1:FRsXN1f5AsAjCGJKqEizvkpNtU+EGNCLh3NxZ/8L+MA=
+github.com/stretchr/testify v1.7.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
+github.com/stretchr/testify v1.8.0/go.mod h1:yNjHg4UonilssWZ8iaSj1OCr/vHnekPRkoO+kdMU+MU=
+github.com/stretchr/testify v1.8.4/go.mod h1:sz/lmYIOXD/1dqDmKjjqLyZ2RngseejIcXlSw2iwfAo=
 github.com/stretchr/testify v1.9.0 h1:HtqpIVDClZ4nwg75+f6Lvsy/wHu+3BoSGCbBAcpTsTg=
 github.com/stretchr/testify v1.9.0/go.mod h1:r2ic/lqez/lEtzL7wO/rwa5dbSLXVDPFyf8C91i36aY=
 github.com/ulikunitz/xz v0.5.11 h1:kpFauv27b6ynzBNT/Xy+1k+fK4WswhN/6PN5WhFAGw8=
@@ -148,6 +158,7 @@ gopkg.in/check.v1 v1.0.0-20201130134442-10cb98267c6c h1:Hei/4ADfdWqJk1ZMxUNpqntN
 gopkg.in/check.v1 v1.0.0-20201130134442-10cb98267c6c/go.mod h1:JHkPIbrfpd72SG/EVd6muEfDQjcINNoR0C8j2r3qZ4Q=
 gopkg.in/ini.v1 v1.67.0 h1:Dgnx+6+nfE+IfzjUEISNeydPJh9AXNNsWbGP9KzCsOA=
 gopkg.in/ini.v1 v1.67.0/go.mod h1:pNLf8WUiyNEtQjuu5G5vTm06TEv9tsIgeAvK8hOrP4k=
+gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
 gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
 gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
 gvisor.dev/gvisor v0.0.0-20230927004350-cbd86285d259 h1:TbRPT0HtzFP3Cno1zZo7yPzEEnfu8EjLfl6IU9VfqkQ=

internal/cli/genkey.go

@@ -0,0 +1,66 @@
+package cli
+
+import (
+	"crypto/rand"
+	"flag"
+	"fmt"
+)
+
+func (c *CLI) GenKey(args []string) (err error) {
+	flagSet := flag.NewFlagSet("genkey", flag.ExitOnError)
+	err = flagSet.Parse(args)
+	if err != nil {
+		return fmt.Errorf("parsing flags: %w", err)
+	}
+
+	const keyLength = 128 / 8
+	keyBytes := make([]byte, keyLength)
+
+	_, _ = rand.Read(keyBytes)
+
+	key := base58Encode(keyBytes)
+	fmt.Println(key)
+
+	return nil
+}
+
+func base58Encode(data []byte) string {
+	const alphabet = "123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz"
+	const radix = 58
+
+	zcount := 0
+	for zcount < len(data) && data[zcount] == 0 {
+		zcount++
+	}
+
+	// integer simplification of ceil(log(256)/log(58))
+	ceilLog256Div58 := (len(data)-zcount)*555/406 + 1 //nolint:gomnd
+	size := zcount + ceilLog256Div58
+
+	output := make([]byte, size)
+
+	high := size - 1
+	for _, b := range data {
+		i := size - 1
+		for carry := uint32(b); i > high || carry != 0; i-- {
+			carry += 256 * uint32(output[i]) //nolint:gomnd
+			output[i] = byte(carry % radix)
+			carry /= radix
+		}
+		high = i
+	}
+
+	// Determine the additional "zero-gap" in the output buffer
+	additionalZeroGapEnd := zcount
+	for additionalZeroGapEnd < size && output[additionalZeroGapEnd] == 0 {
+		additionalZeroGapEnd++
+	}
+
+	val := output[additionalZeroGapEnd-zcount:]
+	size = len(val)
+	for i := range val {
+		output[i] = alphabet[val[i]]
+	}
+
+	return string(output[:size])
+}

internal/configuration/settings/server.go

@@ -19,6 +19,11 @@ type ControlServer struct {
 	// Log can be true or false to enable logging on requests.
 	// It cannot be nil in the internal state.
 	Log *bool
+	// AuthFilePath is the path to the file containing the authentication
+	// configuration for the middleware.
+	// It cannot be empty in the internal state and defaults to
+	// /gluetun/auth/config.toml.
+	AuthFilePath string
 }
 
 func (c ControlServer) validate() (err error) {
@@ -44,8 +49,9 @@ func (c ControlServer) validate() (err error) {
 
 func (c *ControlServer) copy() (copied ControlServer) {
 	return ControlServer{
-		Address: gosettings.CopyPointer(c.Address),
-		Log:     gosettings.CopyPointer(c.Log),
+		Address:      gosettings.CopyPointer(c.Address),
+		Log:          gosettings.CopyPointer(c.Log),
+		AuthFilePath: c.AuthFilePath,
 	}
 }
 
@@ -55,11 +61,13 @@ func (c *ControlServer) copy() (copied ControlServer) {
 func (c *ControlServer) overrideWith(other ControlServer) {
 	c.Address = gosettings.OverrideWithPointer(c.Address, other.Address)
 	c.Log = gosettings.OverrideWithPointer(c.Log, other.Log)
+	c.AuthFilePath = gosettings.OverrideWithComparable(c.AuthFilePath, other.AuthFilePath)
 }
 
 func (c *ControlServer) setDefaults() {
 	c.Address = gosettings.DefaultPointer(c.Address, ":8000")
 	c.Log = gosettings.DefaultPointer(c.Log, true)
+	c.AuthFilePath = gosettings.DefaultComparable(c.AuthFilePath, "/gluetun/auth/config.toml")
 }
 
 func (c ControlServer) String() string {
@@ -70,6 +78,7 @@ func (c ControlServer) toLinesNode() (node *gotree.Node) {
 	node = gotree.New("Control server settings:")
 	node.Appendf("Listening address: %s", *c.Address)
 	node.Appendf("Logging: %s", gosettings.BoolToYesNo(c.Log))
+	node.Appendf("Authentication file path: %s", c.AuthFilePath)
 	return node
 }
 
@@ -78,6 +87,10 @@ func (c *ControlServer) read(r *reader.Reader) (err error) {
 	if err != nil {
 		return err
 	}
+
 	c.Address = r.Get("HTTP_CONTROL_SERVER_ADDRESS")
+
+	c.AuthFilePath = r.String("HTTP_CONTROL_SERVER_AUTH_CONFIG_FILEPATH")
+
 	return nil
 }

internal/configuration/settings/settings_test.go

@@ -70,7 +70,8 @@ func Test_Settings_String(t *testing.T) {
 |   └── Enabled: no
 ├── Control server settings:
 |   ├── Listening address: :8000
-|   └── Logging: yes
+|   ├── Logging: yes
+|   └── Authentication file path: /gluetun/auth/config.toml
 ├── Storage settings:
 |   └── Filepath: /gluetun/servers.json
 ├── OS Alpine settings:

internal/server/handler.go

@@ -2,14 +2,17 @@ package server
 
 import (
 	"context"
+	"fmt"
 	"net/http"
 	"strings"
 
 	"github.com/qdm12/gluetun/internal/models"
+	"github.com/qdm12/gluetun/internal/server/middlewares/auth"
 	"github.com/qdm12/gluetun/internal/server/middlewares/log"
 )
 
-func newHandler(ctx context.Context, logger infoWarner, logging bool,
+func newHandler(ctx context.Context, logger Logger, logging bool,
+	authSettings auth.Settings,
 	buildInfo models.BuildInformation,
 	vpnLooper VPNLooper,
 	pfGetter PortForwardedGetter,
@@ -18,7 +21,7 @@ func newHandler(ctx context.Context, logger infoWarner, logging bool,
 	publicIPLooper PublicIPLoop,
 	storage Storage,
 	ipv6Supported bool,
-) (httpHandler http.Handler) {
+) (httpHandler http.Handler, err error) {
 	handler := &handler{}
 
 	vpn := newVPNHandler(ctx, vpnLooper, storage, ipv6Supported, logger)
@@ -30,14 +33,20 @@ func newHandler(ctx context.Context, logger infoWarner, logging bool,
 	handler.v0 = newHandlerV0(ctx, logger, vpnLooper, dnsLooper, updaterLooper)
 	handler.v1 = newHandlerV1(logger, buildInfo, vpn, openvpn, dns, updater, publicip)
 
+	authMiddleware, err := auth.New(authSettings, logger)
+	if err != nil {
+		return nil, fmt.Errorf("creating auth middleware: %w", err)
+	}
+
 	middlewares := []func(http.Handler) http.Handler{
+		authMiddleware,
 		log.New(logger, logging),
 	}
 	httpHandler = handler
 	for _, middleware := range middlewares {
 		httpHandler = middleware(httpHandler)
 	}
-	return httpHandler
+	return httpHandler, nil
 }
 
 type handler struct {

internal/server/logger.go

@@ -1,8 +1,10 @@
 package server
 
 type Logger interface {
+	Debugf(format string, args ...any)
 	infoer
 	warner
+	Warnf(format string, args ...any)
 	errorer
 }
 

internal/server/middlewares/auth/apikey.go

@@ -0,0 +1,36 @@
+package auth
+
+import (
+	"crypto/sha256"
+	"crypto/subtle"
+	"net/http"
+)
+
+type apiKeyMethod struct {
+	apiKeyDigest [32]byte
+}
+
+func newAPIKeyMethod(apiKey string) *apiKeyMethod {
+	return &apiKeyMethod{
+		apiKeyDigest: sha256.Sum256([]byte(apiKey)),
+	}
+}
+
+// equal returns true if another auth checker is equal.
+// This is used to deduplicate checkers for a particular route.
+func (a *apiKeyMethod) equal(other authorizationChecker) bool {
+	otherTokenMethod, ok := other.(*apiKeyMethod)
+	if !ok {
+		return false
+	}
+	return a.apiKeyDigest == otherTokenMethod.apiKeyDigest
+}
+
+func (a *apiKeyMethod) isAuthorized(_ http.Header, request *http.Request) bool {
+	xAPIKey := request.Header.Get("X-API-Key")
+	if xAPIKey == "" {
+		xAPIKey = request.URL.Query().Get("api_key")
+	}
+	xAPIKeyDigest := sha256.Sum256([]byte(xAPIKey))
+	return subtle.ConstantTimeCompare(xAPIKeyDigest[:], a.apiKeyDigest[:]) == 1
+}

internal/server/middlewares/auth/basic.go

@@ -0,0 +1,37 @@
+package auth
+
+import (
+	"crypto/sha256"
+	"crypto/subtle"
+	"net/http"
+)
+
+type basicAuthMethod struct {
+	authDigest [32]byte
+}
+
+func newBasicAuthMethod(username, password string) *basicAuthMethod {
+	return &basicAuthMethod{
+		authDigest: sha256.Sum256([]byte(username + password)),
+	}
+}
+
+// equal returns true if another auth checker is equal.
+// This is used to deduplicate checkers for a particular route.
+func (a *basicAuthMethod) equal(other authorizationChecker) bool {
+	otherBasicMethod, ok := other.(*basicAuthMethod)
+	if !ok {
+		return false
+	}
+	return a.authDigest == otherBasicMethod.authDigest
+}
+
+func (a *basicAuthMethod) isAuthorized(headers http.Header, request *http.Request) bool {
+	username, password, ok := request.BasicAuth()
+	if !ok {
+		headers.Set("WWW-Authenticate", `Basic realm="restricted", charset="UTF-8"`)
+		return false
+	}
+	requestAuthDigest := sha256.Sum256([]byte(username + password))
+	return subtle.ConstantTimeCompare(a.authDigest[:], requestAuthDigest[:]) == 1
+}