stack/ee/auth/pkg/oidc/oidc_test.go

package oidc_test

import (
	"bytes"
	"context"
	"crypto/rand"
	"crypto/rsa"
	"encoding/json"
	"fmt"
	"net"
	"net/http"
	"net/http/httptest"
	"net/http/httputil"
	"net/url"
	"testing"
	"time"

	auth "github.com/formancehq/auth/pkg"
	"github.com/formancehq/auth/pkg/delegatedauth"
	"github.com/formancehq/auth/pkg/oidc"
	"github.com/formancehq/auth/pkg/storage/sqlstorage"
	"github.com/formancehq/stack/libs/go-libs/pgtesting"
	"github.com/golang-jwt/jwt"
	"github.com/gorilla/mux"
	"github.com/oauth2-proxy/mockoidc"
	"github.com/stretchr/testify/require"
	"github.com/zitadel/oidc/v2/pkg/client/rp"
	"github.com/zitadel/oidc/v2/pkg/client/rs"
	zoidc "github.com/zitadel/oidc/v2/pkg/oidc"
	"github.com/zitadel/oidc/v2/pkg/op"
	"golang.org/x/oauth2/clientcredentials"
	"gorm.io/driver/postgres"
	"gorm.io/gorm"
)

type user struct {
	*mockoidc.MockUser
}

func (u *user) Userinfo(scope []string) ([]byte, error) {
	encoded, err := u.MockUser.Userinfo(scope)
	if err != nil {
		return nil, err
	}

	m := make(map[string]any)
	if err := json.Unmarshal(encoded, &m); err != nil {
		return nil, err
	}
	m["sub"] = u.Subject
	return json.Marshal(m)
}

func withServer(t *testing.T, fn func(m *mockoidc.MockOIDC, storage *sqlstorage.Storage, issuer string, provider op.OpenIDProvider)) {
	t.Parallel()

	// Create a mock OIDC server which will always return a default user
	mockOIDC, err := mockoidc.Run()
	require.NoError(t, err)
	defer func() {
		require.NoError(t, mockOIDC.Shutdown())
	}()

	// Prepare a tcp connection, listening on :0 to select a random port
	l, err := net.Listen("tcp", "127.0.0.1:0")
	require.NoError(t, err)

	// Compute server url, it will be the "issuer" of our oidc provider
	serverUrl := fmt.Sprintf("http://%s", l.Addr().String())

	// As our oidc provider, is also a relying party (it delegates authentication), we need to construct a relying party
	// with information from the mock
	cl := http.DefaultClient
	cl.Transport = RoundTripper{http.DefaultTransport}
	serverRelyingParty, err := rp.NewRelyingPartyOIDC(mockOIDC.Issuer(), mockOIDC.ClientID, mockOIDC.ClientSecret,
		fmt.Sprintf("%s/authorize/callback", serverUrl), []string{"openid", "email"}, rp.WithHTTPClient(cl))
	require.NoError(t, err)

	postgresDB := pgtesting.NewPostgresDatabase(t)
	dialector := postgres.Open(postgresDB.ConnString())

	// Construct our storage
	db, err := sqlstorage.LoadGorm(dialector, &gorm.Config{})
	require.NoError(t, err)
	require.NoError(t, sqlstorage.MigrateTables(context.Background(), db))

	sqlDB, err := db.DB()
	require.NoError(t, err)
	defer sqlDB.Close()

	storage := sqlstorage.New(db)

	key, _ := rsa.GenerateKey(rand.Reader, 2048)
	storageFacade := oidc.NewStorageFacade(storage, serverRelyingParty, key)

	keySet, err := oidc.ReadKeySet(http.DefaultClient, context.Background(), delegatedauth.Config{
		Issuer:       mockOIDC.Issuer(),
		ClientID:     mockOIDC.ClientID,
		ClientSecret: mockOIDC.ClientSecret,
	})
	require.NoError(t, err)

	// Construct our oidc provider
	provider, err := oidc.NewOpenIDProvider(storageFacade, serverUrl, mockOIDC.Issuer(), keySet)
	require.NoError(t, err)

	// Create the router
	router := mux.NewRouter()
	oidc.AddRoutes(router, provider, storage, serverRelyingParty)

	// Create our http server for our oidc provider
	providerHttpServer := &http.Server{
		Handler:           router,
		ReadHeaderTimeout: 5 * time.Second,
	}
	go func() {
		err := providerHttpServer.Serve(l)
		if err != http.ErrServerClosed {
			require.Fail(t, err.Error())
		}
	}()
	defer providerHttpServer.Close()

	fn(mockOIDC, storage, serverUrl, provider)
}

func Test3LeggedFlow(t *testing.T) {
	withServer(t, func(m *mockoidc.MockOIDC, storage *sqlstorage.Storage, issuer string, provider op.OpenIDProvider) {
		// Create ou http server for our client (a web application for example)
		codeChan := make(chan string, 1) // Just store codes coming from our provider inside a chan
		clientHandler := http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
			codeChan <- r.URL.Query().Get("code")
		})
		clientHttpServer := httptest.NewServer(clientHandler)
		defer clientHttpServer.Close()

		// Create a OAuth2 client which represent our client application
		client := auth.NewClient(auth.ClientOptions{})
		client.RedirectURIs.Append(clientHttpServer.URL)          // Need to configure the redirect uri
		_, clear := client.GenerateNewSecret(auth.SecretCreate{}) // Need to generate a secret
		require.NoError(t, storage.SaveClient(context.TODO(), *client))

		// As our client is a relying party, we can use the library to get some helpers
		clientRelyingParty, err := rp.NewRelyingPartyOIDC(issuer, client.Id, clear, client.RedirectURIs[0], []string{"openid", "email"})
		require.NoError(t, err)

		m.QueueUser(&user{
			MockUser: mockoidc.DefaultUser(),
		})

		// Trigger an authentication request
		authUrl := rp.AuthURL("", clientRelyingParty)
		if testing.Verbose() {
			fmt.Printf("URL:%s\n", authUrl)
		}
		rsp, err := http.Get(authUrl)
		require.NoError(t, err)
		require.Equal(t, http.StatusOK, rsp.StatusCode)

		select {
		// As the mock automatically accept login response, we should have received a code
		case code := <-codeChan:
			// And this code is used to get a token
			tokens, err := rp.CodeExchange[*zoidc.IDTokenClaims](context.TODO(), code, clientRelyingParty)
			require.NoError(t, err)
			require.Equal(t, time.Until(tokens.Expiry).Round(oidc.ExpirationToken3Legged), oidc.ExpirationToken3Legged)

			// Create a OAuth2 client which represent our client application
			secondaryClient := auth.NewClient(auth.ClientOptions{
				Trusted: true,
			})
			_, clear = secondaryClient.GenerateNewSecret(auth.SecretCreate{}) // Need to generate a secret
			require.NoError(t, storage.SaveClient(context.TODO(), *secondaryClient))

			resourceServer, err := rs.NewResourceServerClientCredentials(issuer, secondaryClient.Id, clear)
			require.NoError(t, err)

			introspection, err := rs.Introspect(context.TODO(), resourceServer, tokens.AccessToken)
			require.NoError(t, err)
			require.True(t, introspection.Active)

			user, err := storage.FindUser(context.TODO(), tokens.IDTokenClaims.GetSubject())
			require.NoError(t, err)
			require.NotEmpty(t, user.Email)
		default:
			require.Fail(t, "code was expected")
		}
	})
}

type RoundTripper struct {
	http.RoundTripper
}

func (r RoundTripper) RoundTrip(req *http.Request) (*http.Response, error) {
	by, err := httputil.DumpRequest(req, true)
	if err != nil {
		return nil, err
	}
	if testing.Verbose() {
		fmt.Printf("REQ:%s\n", string(by))
	}
	resp, err := r.RoundTripper.RoundTrip(req)
	if err != nil {
		return nil, err
	}
	by, err = httputil.DumpResponse(resp, true)
	if err != nil {
		return nil, err
	}
	if testing.Verbose() {
		fmt.Printf("RESP:%s\n", string(by))
	}
	return resp, err
}

var _ http.RoundTripper = RoundTripper{}

func TestJWTAssertions(t *testing.T) {
	withServer(t, func(m *mockoidc.MockOIDC, storage *sqlstorage.Storage, issuer string, provider op.OpenIDProvider) {

		// Create a OAuth2 client which represent our client application
		client := auth.NewClient(auth.ClientOptions{})
		_, clear := client.GenerateNewSecret(auth.SecretCreate{}) // Need to generate a secret
		require.NoError(t, storage.SaveClient(context.TODO(), *client))

		// As our client is a relying party, we can use the library to get some helpers
		clientRelyingParty, err := rp.NewRelyingPartyOIDC(m.Issuer(), client.Id, clear, "", []string{"openid", "email"})
		require.NoError(t, err)

		token, err := m.Keypair.SignJWT(jwt.MapClaims{
			"aud": []string{m.Issuer()},
			"exp": time.Now().Add(5 * time.Minute).Unix(),
			"iss": m.Issuer(),
		})
		require.NoError(t, err)

		// Create a OAuth2 client which represent our client application
		form := url.Values{
			"grant_type": []string{"urn:ietf:params:oauth:grant-type:jwt-bearer"},
			"assertion":  []string{token},
			"scope":      []string{"openid email"},
		}
		req, err := http.NewRequest(http.MethodPost, clientRelyingParty.OAuthConfig().Endpoint.TokenURL,
			bytes.NewBufferString(form.Encode()))
		require.NoError(t, err)
		req.SetBasicAuth(client.Id, clear)
		req.Header.Set("Content-Type", "application/x-www-form-urlencoded")

		_, err = http.DefaultClient.Do(req)
		require.NoError(t, err)
	})
}

func TestClientCredentials(t *testing.T) {
	withServer(t, func(m *mockoidc.MockOIDC, storage *sqlstorage.Storage, issuer string, provider op.OpenIDProvider) {

		// Create a OAuth2 client which represent our client application
		client := auth.NewClient(auth.ClientOptions{})
		_, clear := client.GenerateNewSecret(auth.SecretCreate{}) // Need to generate a secret
		require.NoError(t, storage.SaveClient(context.TODO(), *client))

		// As our client is a relying party, we can use the library to get some helpers
		clientRelyingParty, err := rp.NewRelyingPartyOIDC(issuer, client.Id, clear, "", []string{"openid", "email"})
		require.NoError(t, err)

		// Create a OAuth2 client which represent our client application
		clientCredentialsConfig := clientcredentials.Config{
			ClientID:     client.Id,
			ClientSecret: clear,
			TokenURL:     clientRelyingParty.OAuthConfig().Endpoint.TokenURL,
			Scopes:       []string{},
		}
		token, err := clientCredentialsConfig.Token(context.Background())
		require.NoError(t, err)
		require.Equal(t, time.Until(token.Expiry).Round(oidc.ExpirationToken2Legged), oidc.ExpirationToken2Legged)
	})
}