feat: allow bypassing of basic auth from a list of authorized cidrs (#50)

Dockerfile

@@ -1,4 +1,4 @@
-FROM reg.cadoles.com/proxy_cache/library/golang:1.23 AS BUILD
+FROM reg.cadoles.com/proxy_cache/library/golang:1.24.2 AS build
 
 RUN apt-get update \
     && apt-get install -y make
@@ -33,7 +33,7 @@ RUN /src/dist/bouncer_linux_amd64_v1/bouncer -c '' config dump > /src/dist/bounc
     && yq -i '.bootstrap.lockTimeout = "30s"' /src/dist/bouncer_linux_amd64_v1/config.yml \
     && yq -i '.integrations.kubernetes.lockTimeout = "30s"' /src/dist/bouncer_linux_amd64_v1/config.yml
 
-FROM reg.cadoles.com/proxy_cache/library/alpine:3.20 AS RUNTIME
+FROM reg.cadoles.com/proxy_cache/library/alpine:3.21 AS runtime
 
 RUN apk add --no-cache ca-certificates dumb-init
 
@@ -41,10 +41,10 @@ ENTRYPOINT ["/usr/bin/dumb-init", "--"]
 
 RUN mkdir -p /usr/local/bin /usr/share/bouncer/bin /etc/bouncer
 
-COPY --from=BUILD /src/dist/bouncer_linux_amd64_v1/bouncer /usr/share/bouncer/bin/bouncer
-COPY --from=BUILD /src/layers /usr/share/bouncer/layers
-COPY --from=BUILD /src/templates /usr/share/bouncer/templates
-COPY --from=BUILD /src/dist/bouncer_linux_amd64_v1/config.yml /etc/bouncer/config.yml
+COPY --from=build /src/dist/bouncer_linux_amd64_v1/bouncer /usr/share/bouncer/bin/bouncer
+COPY --from=build /src/layers /usr/share/bouncer/layers
+COPY --from=build /src/templates /usr/share/bouncer/templates
+COPY --from=build /src/dist/bouncer_linux_amd64_v1/config.yml /etc/bouncer/config.yml
 
 RUN ln -s /usr/share/bouncer/bin/bouncer /usr/local/bin/bouncer
 

internal/cidr/match.go

@@ -0,0 +1,42 @@
+package cidr
+
+import (
+	"net"
+	"strings"
+
+	"github.com/pkg/errors"
+)
+
+func MatchAny(hostPort string, CIDRs ...string) (bool, error) {
+	var remoteHost string
+	if strings.Contains(hostPort, ":") {
+		var err error
+		remoteHost, _, err = net.SplitHostPort(hostPort)
+		if err != nil {
+			return false, errors.WithStack(err)
+		}
+	} else {
+		remoteHost = hostPort
+	}
+
+	remoteAddr := net.ParseIP(remoteHost)
+	if remoteAddr == nil {
+		return false, errors.Errorf("remote host '%s' is not a valid ip address", remoteHost)
+	}
+
+	for _, rawCIDR := range CIDRs {
+		_, net, err := net.ParseCIDR(rawCIDR)
+		if err != nil {
+			return false, errors.WithStack(err)
+		}
+
+		match := net.Contains(remoteAddr)
+		if !match {
+			continue
+		}
+
+		return true, nil
+	}
+
+	return false, nil
+}

internal/cidr/match_test.go

@@ -1,15 +1,13 @@
-package network
+package cidr
 
 import (
-	"context"
 	"fmt"
 	"testing"
 
 	"github.com/pkg/errors"
 )
 
-func TestMatchAuthorizedCIDRs(t *testing.T) {
-
+func TestMatchAny(t *testing.T) {
 	type testCase struct {
 		RemoteHostPort  string
 		AuthorizedCIDRs []string
@@ -56,14 +54,16 @@ func TestMatchAuthorizedCIDRs(t *testing.T) {
 			},
 			ExpectedResult: false,
 		},
+		{
+			RemoteHostPort:  "[2001:0db8:0000:85a3:0000:0000:ac1f:8001]:8001",
+			AuthorizedCIDRs: []string{"2000::/3"},
+			ExpectedResult:  true,
+		},
 	}
 
-	auth := Authenticator{}
-	ctx := context.Background()
-
 	for idx, tc := range testCases {
 		t.Run(fmt.Sprintf("Case #%d", idx), func(t *testing.T) {
-			result, err := auth.matchAnyAuthorizedCIDRs(ctx, tc.RemoteHostPort, tc.AuthorizedCIDRs)
+			result, err := MatchAny(tc.RemoteHostPort, tc.AuthorizedCIDRs...)
 
 			if g, e := result, tc.ExpectedResult; e != g {
 				t.Errorf("result: expected '%v', got '%v'", e, g)

internal/proxy/director/layer/authn/basic/authenticator.go

@@ -6,6 +6,7 @@ import (
 	"fmt"
 	"net/http"
 
+	"forge.cadoles.com/cadoles/bouncer/internal/cidr"
 	"forge.cadoles.com/cadoles/bouncer/internal/proxy/director/layer/authn"
 	"forge.cadoles.com/cadoles/bouncer/internal/store"
 	"github.com/pkg/errors"
@@ -23,6 +24,16 @@ func (a *Authenticator) Authenticate(w http.ResponseWriter, r *http.Request, lay
 		return nil, errors.WithStack(err)
 	}
 
+	matches, err := cidr.MatchAny(r.RemoteAddr, options.AuthorizedCIDRs...)
+	if err != nil {
+		return nil, errors.WithStack(err)
+	}
+
+	if matches {
+		user := authn.NewUser(r.RemoteAddr, map[string]any{})
+		return user, nil
+	}
+
 	username, password, ok := r.BasicAuth()
 
 	unauthorized := func() {

internal/proxy/director/layer/authn/basic/authenticator_test.go

@@ -0,0 +1,130 @@
+package basic
+
+import (
+	"encoding/base64"
+	"net/http/httptest"
+	"testing"
+
+	"forge.cadoles.com/cadoles/bouncer/internal/proxy/director/layer/authn"
+	"forge.cadoles.com/cadoles/bouncer/internal/store"
+	"github.com/pkg/errors"
+)
+
+func TestAuthenticatorWithCredentials(t *testing.T) {
+	r := httptest.NewRequest("GET", "/", nil)
+	w := httptest.NewRecorder()
+
+	r.Header.Set("Authorization", "Basic "+basicAuth("foo", "bar"))
+
+	authenticator := &Authenticator{}
+
+	layer := &store.Layer{
+		LayerHeader: store.LayerHeader{
+			Proxy:    "test",
+			Name:     "test",
+			Revision: 0,
+			Type:     LayerType,
+			Enabled:  true,
+		},
+		Options: store.LayerOptions{
+			"users": []map[string]any{
+				{
+					"username":     "foo",
+					"passwordHash": "$2y$10$S3CfWRRMbOrOu3zUapZnfeU8xLtjH.MycWcvMRVHdc9RAty8lnn5q",
+				},
+			},
+		},
+	}
+
+	user, err := authenticator.Authenticate(w, r, layer)
+	if err != nil {
+		t.Fatalf("%+v", errors.WithStack(err))
+	}
+
+	if user == nil {
+		t.Fatalf("user should not be nil")
+	}
+
+	if e, g := "foo", user.Subject; e != g {
+		t.Fatalf("user.Subject: expected '%v', got '%v'", e, g)
+	}
+
+	r = httptest.NewRequest("GET", "/", nil)
+	w = httptest.NewRecorder()
+
+	r.Header.Set("Authorization", "Basic "+basicAuth("foo", "qsdq;sdqks"))
+
+	user, err = authenticator.Authenticate(w, r, layer)
+	if err == nil {
+		t.Errorf("err should not be nil")
+	}
+
+	if !errors.Is(err, authn.ErrSkipRequest) {
+		t.Errorf("err: expected %T, got %T", authn.ErrSkipRequest, err)
+	}
+
+	if user != nil {
+		t.Errorf("user should be nil")
+	}
+}
+
+func TestAuthenticatorWithAuthorizedRemoteAddr(t *testing.T) {
+	r := httptest.NewRequest("GET", "/", nil)
+	w := httptest.NewRecorder()
+
+	// Authorized address
+	r.RemoteAddr = "192.168.30.21"
+
+	authenticator := &Authenticator{}
+
+	layer := &store.Layer{
+		LayerHeader: store.LayerHeader{
+			Proxy:    "test",
+			Name:     "test",
+			Revision: 0,
+			Type:     LayerType,
+			Enabled:  true,
+		},
+		Options: store.LayerOptions{
+			"users":           []map[string]any{},
+			"authorizedCIDRs": []string{"192.168.30.1/24"},
+		},
+	}
+
+	user, err := authenticator.Authenticate(w, r, layer)
+	if err != nil {
+		t.Fatalf("%+v", errors.WithStack(err))
+	}
+
+	if user == nil {
+		t.Fatalf("user should not be nil")
+	}
+
+	if e, g := "192.168.30.21", user.Subject; e != g {
+		t.Fatalf("user.Subject: expected '%v', got '%v'", e, g)
+	}
+
+	r = httptest.NewRequest("GET", "/", nil)
+	w = httptest.NewRecorder()
+
+	// Unauthorized address
+	r.RemoteAddr = "192.168.40.36"
+
+	user, err = authenticator.Authenticate(w, r, layer)
+	if err == nil {
+		t.Errorf("err should not be nil")
+	}
+
+	if !errors.Is(err, authn.ErrSkipRequest) {
+		t.Errorf("err: expected %T, got %T", authn.ErrSkipRequest, err)
+	}
+
+	if user != nil {
+		t.Errorf("user should be nil")
+	}
+}
+
+func basicAuth(username, password string) string {
+	auth := username + ":" + password
+	return base64.StdEncoding.EncodeToString([]byte(auth))
+}

internal/proxy/director/layer/authn/basic/layer-options.json

@@ -34,6 +34,14 @@
                 ],
                 "additionalProperties": false
             }
+        },
+        "authorizedCIDRs": {
+            "title": "Liste des adresses réseau d'origine autorisées à contourner l'authentification (au format CIDR)",
+            "default": [],
+            "type": "array",
+            "items": {
+                "type": "string"
+            }
         }
     },
     "additionalProperties": false

internal/proxy/director/layer/authn/basic/layer_options.go

@@ -9,8 +9,9 @@ import (
 
 type LayerOptions struct {
 	authn.LayerOptions
-	Users []User `mapstructure:"users"`
-	Realm string `mapstructure:"realm"`
+	Users           []User   `mapstructure:"users"`
+	Realm           string   `mapstructure:"realm"`
+	AuthorizedCIDRs []string `mapstructure:"authorizedCIDRs"`
 }
 
 type User struct {
@@ -21,9 +22,10 @@ type User struct {
 
 func fromStoreOptions(storeOptions store.LayerOptions) (*LayerOptions, error) {
 	layerOptions := LayerOptions{
-		LayerOptions: authn.DefaultLayerOptions(),
-		Realm:        "Restricted area",
-		Users:        make([]User, 0),
+		LayerOptions:    authn.DefaultLayerOptions(),
+		Realm:           "Restricted area",
+		Users:           make([]User, 0),
+		AuthorizedCIDRs: make([]string, 0),
 	}
 
 	config := mapstructure.DecoderConfig{

internal/proxy/director/layer/authn/network/authenticator.go

@@ -1,16 +1,13 @@
 package network
 
 import (
-	"context"
-	"net"
 	"net/http"
-	"strings"
 
+	"forge.cadoles.com/cadoles/bouncer/internal/cidr"
 	"forge.cadoles.com/cadoles/bouncer/internal/proxy/director/layer/authn"
 	"forge.cadoles.com/cadoles/bouncer/internal/store"
 	"github.com/pkg/errors"
 	"github.com/prometheus/client_golang/prometheus"
-	"gitlab.com/wpetit/goweb/logger"
 )
 
 type Authenticator struct {
@@ -18,14 +15,12 @@ type Authenticator struct {
 
 // Authenticate implements authn.Authenticator.
 func (a *Authenticator) Authenticate(w http.ResponseWriter, r *http.Request, layer *store.Layer) (*authn.User, error) {
-	ctx := r.Context()
-
 	options, err := fromStoreOptions(layer.Options)
 	if err != nil {
 		return nil, errors.WithStack(err)
 	}
 
-	matches, err := a.matchAnyAuthorizedCIDRs(ctx, r.RemoteAddr, options.AuthorizedCIDRs)
+	matches, err := cidr.MatchAny(r.RemoteAddr, options.AuthorizedCIDRs...)
 	if err != nil {
 		return nil, errors.WithStack(err)
 	}
@@ -49,42 +44,6 @@ func (a *Authenticator) Authenticate(w http.ResponseWriter, r *http.Request, lay
 	return user, nil
 }
 
-func (a *Authenticator) matchAnyAuthorizedCIDRs(ctx context.Context, remoteHostPort string, CIDRs []string) (bool, error) {
-	var remoteHost string
-	if strings.Contains(remoteHostPort, ":") {
-		var err error
-		remoteHost, _, err = net.SplitHostPort(remoteHostPort)
-		if err != nil {
-			return false, errors.WithStack(err)
-		}
-	} else {
-		remoteHost = remoteHostPort
-	}
-
-	remoteAddr := net.ParseIP(remoteHost)
-	if remoteAddr == nil {
-		return false, errors.Errorf("remote host '%s' is not a valid ip address", remoteHost)
-	}
-
-	for _, rawCIDR := range CIDRs {
-		_, net, err := net.ParseCIDR(rawCIDR)
-		if err != nil {
-			return false, errors.WithStack(err)
-		}
-
-		match := net.Contains(remoteAddr)
-		if !match {
-			continue
-		}
-
-		return true, nil
-	}
-
-	logger.Debug(ctx, "comparing remote host with authorized cidrs", logger.F("remoteAddr", remoteAddr))
-
-	return false, nil
-}
-
 var (
 	_ authn.Authenticator = &Authenticator{}
 )