feat: allow introspection and device code endpoints to use Federated Client Credentials (#640)

backend/internal/controller/e2etest_controller.go

@@ -14,6 +14,7 @@ func NewTestController(group *gin.RouterGroup, testService *service.TestService)
 	testController := &TestController{TestService: testService}
 
 	group.POST("/test/reset", testController.resetAndSeedHandler)
+	group.POST("/test/refreshtoken", testController.signRefreshToken)
 
 	group.GET("/externalidp/jwks.json", testController.externalIdPJWKS)
 	group.POST("/externalidp/sign", testController.externalIdPSignToken)
@@ -100,3 +101,24 @@ func (tc *TestController) externalIdPSignToken(c *gin.Context) {
 
 	c.Writer.WriteString(token)
 }
+
+func (tc *TestController) signRefreshToken(c *gin.Context) {
+	var input struct {
+		UserID       string `json:"user"`
+		ClientID     string `json:"client"`
+		RefreshToken string `json:"rt"`
+	}
+	err := c.ShouldBindJSON(&input)
+	if err != nil {
+		_ = c.Error(err)
+		return
+	}
+
+	token, err := tc.TestService.SignRefreshToken(input.UserID, input.ClientID, input.RefreshToken)
+	if err != nil {
+		_ = c.Error(err)
+		return
+	}
+
+	c.Writer.WriteString(token)
+}

backend/internal/controller/oidc_controller.go

@@ -200,7 +200,7 @@ func (oc *OidcController) userInfoHandler(c *gin.Context) {
 		return
 	}
 
-	token, err := oc.jwtService.VerifyOauthAccessToken(authToken)
+	token, err := oc.jwtService.VerifyOAuthAccessToken(authToken)
 	if err != nil {
 		_ = c.Error(err)
 		return
@@ -308,9 +308,21 @@ func (oc *OidcController) introspectTokenHandler(c *gin.Context) {
 	// find valid tokens) while still allowing it to be used by an application that is
 	// supposed to interact with our IdP (since that needs to have a client_id
 	// and client_secret anyway).
-	clientID, clientSecret, _ := c.Request.BasicAuth()
+	var (
+		creds service.ClientAuthCredentials
+		ok    bool
+	)
+	creds.ClientID, creds.ClientSecret, ok = c.Request.BasicAuth()
+	if !ok {
+		// If there's no basic auth, check if we have a bearer token
+		bearer, ok := utils.BearerAuth(c.Request)
+		if ok {
+			creds.ClientAssertionType = service.ClientAssertionTypeJWTBearer
+			creds.ClientAssertion = bearer
+		}
+	}
 
-	response, err := oc.oidcService.IntrospectToken(c.Request.Context(), clientID, clientSecret, input.Token)
+	response, err := oc.oidcService.IntrospectToken(c.Request.Context(), creds, input.Token)
 	if err != nil {
 		_ = c.Error(err)
 		return

backend/internal/dto/oidc_dto.go

@@ -116,6 +116,8 @@ type OidcDeviceAuthorizationRequestDto struct {
 	ClientID            string `form:"client_id" binding:"required"`
 	Scope               string `form:"scope" binding:"required"`
 	ClientSecret        string `form:"client_secret"`
+	ClientAssertion     string `form:"client_assertion"`
+	ClientAssertionType string `form:"client_assertion_type"`
 }
 
 type OidcDeviceAuthorizationResponseDto struct {

backend/internal/service/e2etest_service.go

@@ -479,6 +479,10 @@ func (s *TestService) SetLdapTestConfig(ctx context.Context) error {
 	return nil
 }
 
+func (s *TestService) SignRefreshToken(userID, clientID, refreshToken string) (string, error) {
+	return s.jwtService.GenerateOAuthRefreshToken(userID, clientID, refreshToken)
+}
+
 // GetExternalIdPJWKS returns the JWKS for the "external IdP".
 func (s *TestService) GetExternalIdPJWKS() (jwk.Set, error) {
 	pubKey, err := s.externalIdPKey.PublicKey()

backend/internal/service/jwt_service.go

@@ -39,9 +39,15 @@ const (
 	// TokenTypeClaim is the claim used to identify the type of token
 	TokenTypeClaim = "type"
 
+	// RefreshTokenClaim is the claim used for the refresh token's value
+	RefreshTokenClaim = "rt"
+
 	// OAuthAccessTokenJWTType identifies a JWT as an OAuth access token
 	OAuthAccessTokenJWTType = "oauth-access-token" //nolint:gosec
 
+	// OAuthRefreshTokenJWTType identifies a JWT as an OAuth refresh token
+	OAuthRefreshTokenJWTType = "refresh-token"
+
 	// AccessTokenJWTType identifies a JWT as an access token used by Pocket ID
 	AccessTokenJWTType = "access-token"
 
@@ -322,8 +328,8 @@ func (s *JwtService) VerifyIdToken(tokenString string, acceptExpiredTokens bool)
 	return token, nil
 }
 
-// BuildOauthAccessToken creates an OAuth access token with all claims
-func (s *JwtService) BuildOauthAccessToken(user model.User, clientID string) (jwt.Token, error) {
+// BuildOAuthAccessToken creates an OAuth access token with all claims
+func (s *JwtService) BuildOAuthAccessToken(user model.User, clientID string) (jwt.Token, error) {
 	now := time.Now()
 	token, err := jwt.NewBuilder().
 		Subject(user.ID).
@@ -348,9 +354,9 @@ func (s *JwtService) BuildOauthAccessToken(user model.User, clientID string) (jw
 	return token, nil
 }
 
-// GenerateOauthAccessToken creates and signs an OAuth access token
-func (s *JwtService) GenerateOauthAccessToken(user model.User, clientID string) (string, error) {
-	token, err := s.BuildOauthAccessToken(user, clientID)
+// GenerateOAuthAccessToken creates and signs an OAuth access token
+func (s *JwtService) GenerateOAuthAccessToken(user model.User, clientID string) (string, error) {
+	token, err := s.BuildOAuthAccessToken(user, clientID)
 	if err != nil {
 		return "", err
 	}
@@ -364,7 +370,7 @@ func (s *JwtService) GenerateOauthAccessToken(user model.User, clientID string)
 	return string(signed), nil
 }
 
-func (s *JwtService) VerifyOauthAccessToken(tokenString string) (jwt.Token, error) {
+func (s *JwtService) VerifyOAuthAccessToken(tokenString string) (jwt.Token, error) {
 	alg, _ := s.privateKey.Algorithm()
 	token, err := jwt.ParseString(
 		tokenString,
@@ -381,6 +387,96 @@ func (s *JwtService) VerifyOauthAccessToken(tokenString string) (jwt.Token, erro
 	return token, nil
 }
 
+func (s *JwtService) GenerateOAuthRefreshToken(userID string, clientID string, refreshToken string) (string, error) {
+	now := time.Now()
+	token, err := jwt.NewBuilder().
+		Subject(userID).
+		Expiration(now.Add(RefreshTokenDuration)).
+		IssuedAt(now).
+		Issuer(common.EnvConfig.AppURL).
+		Build()
+	if err != nil {
+		return "", fmt.Errorf("failed to build token: %w", err)
+	}
+
+	err = token.Set(RefreshTokenClaim, refreshToken)
+	if err != nil {
+		return "", fmt.Errorf("failed to set 'rt' claim in token: %w", err)
+	}
+
+	err = SetAudienceString(token, clientID)
+	if err != nil {
+		return "", fmt.Errorf("failed to set 'aud' claim in token: %w", err)
+	}
+
+	err = SetTokenType(token, OAuthRefreshTokenJWTType)
+	if err != nil {
+		return "", fmt.Errorf("failed to set 'type' claim in token: %w", err)
+	}
+
+	alg, _ := s.privateKey.Algorithm()
+	signed, err := jwt.Sign(token, jwt.WithKey(alg, s.privateKey))
+	if err != nil {
+		return "", fmt.Errorf("failed to sign token: %w", err)
+	}
+
+	return string(signed), nil
+}
+
+func (s *JwtService) VerifyOAuthRefreshToken(tokenString string) (userID, clientID, rt string, err error) {
+	alg, _ := s.privateKey.Algorithm()
+	token, err := jwt.ParseString(
+		tokenString,
+		jwt.WithValidate(true),
+		jwt.WithKey(alg, s.privateKey),
+		jwt.WithAcceptableSkew(clockSkew),
+		jwt.WithIssuer(common.EnvConfig.AppURL),
+		jwt.WithValidator(TokenTypeValidator(OAuthRefreshTokenJWTType)),
+	)
+	if err != nil {
+		return "", "", "", fmt.Errorf("failed to parse token: %w", err)
+	}
+
+	err = token.Get(RefreshTokenClaim, &rt)
+	if err != nil {
+		return "", "", "", fmt.Errorf("failed to get '%s' claim from token: %w", RefreshTokenClaim, err)
+	}
+
+	audiences, ok := token.Audience()
+	if !ok || len(audiences) != 1 || audiences[0] == "" {
+		return "", "", "", errors.New("failed to get 'aud' claim from token")
+	}
+	clientID = audiences[0]
+
+	userID, ok = token.Subject()
+	if !ok {
+		return "", "", "", errors.New("failed to get 'sub' claim from token")
+	}
+
+	return userID, clientID, rt, nil
+}
+
+// GetTokenType returns the type of the JWT token issued by Pocket ID, but **does not validate it**.
+func (s *JwtService) GetTokenType(tokenString string) (string, jwt.Token, error) {
+	// Disable validation and verification to parse the token without checking it
+	token, err := jwt.ParseString(
+		tokenString,
+		jwt.WithValidate(false),
+		jwt.WithVerify(false),
+	)
+	if err != nil {
+		return "", nil, fmt.Errorf("failed to parse token: %w", err)
+	}
+
+	var tokenType string
+	err = token.Get(TokenTypeClaim, &tokenType)
+	if err != nil {
+		return "", nil, fmt.Errorf("failed to get token type claim: %w", err)
+	}
+
+	return tokenType, token, nil
+}
+
 // GetPublicJWK returns the JSON Web Key (JWK) for the public key.
 func (s *JwtService) GetPublicJWK() (jwk.Key, error) {
 	if s.privateKey == nil {
@@ -478,7 +574,10 @@ func GetIsAdmin(token jwt.Token) (bool, error) {
 	}
 	var isAdmin bool
 	err := token.Get(IsAdminClaim, &isAdmin)
-	return isAdmin, err
+	if err != nil {
+		return false, fmt.Errorf("failed to get 'isAdmin' claim from token: %w", err)
+	}
+	return isAdmin, nil
 }
 
 // SetTokenType sets the "type" claim in the token

backend/internal/service/jwt_service_test.go

@@ -882,7 +882,7 @@ func TestGenerateVerifyIdToken(t *testing.T) {
 	})
 }
 
-func TestGenerateVerifyOauthAccessToken(t *testing.T) {
+func TestGenerateVerifyOAuthAccessToken(t *testing.T) {
 	// Create a temporary directory for the test
 	tempDir := t.TempDir()
 
@@ -914,12 +914,12 @@ func TestGenerateVerifyOauthAccessToken(t *testing.T) {
 		const clientID = "test-client-123"
 
 		// Generate a token
-		tokenString, err := service.GenerateOauthAccessToken(user, clientID)
+		tokenString, err := service.GenerateOAuthAccessToken(user, clientID)
 		require.NoError(t, err, "Failed to generate OAuth access token")
 		assert.NotEmpty(t, tokenString, "Token should not be empty")
 
 		// Verify the token
-		claims, err := service.VerifyOauthAccessToken(tokenString)
+		claims, err := service.VerifyOAuthAccessToken(tokenString)
 		require.NoError(t, err, "Failed to verify generated OAuth access token")
 
 		// Check the claims
@@ -972,7 +972,7 @@ func TestGenerateVerifyOauthAccessToken(t *testing.T) {
 		require.NoError(t, err, "Failed to sign token")
 
 		// Verify should fail due to expiration
-		_, err = service.VerifyOauthAccessToken(string(signed))
+		_, err = service.VerifyOAuthAccessToken(string(signed))
 		require.Error(t, err, "Verification should fail with expired token")
 		assert.Contains(t, err.Error(), `"exp" not satisfied`, "Error message should indicate token verification failure")
 	})
@@ -996,11 +996,11 @@ func TestGenerateVerifyOauthAccessToken(t *testing.T) {
 		const clientID = "test-client-789"
 
 		// Generate a token with the first service
-		tokenString, err := service1.GenerateOauthAccessToken(user, clientID)
+		tokenString, err := service1.GenerateOAuthAccessToken(user, clientID)
 		require.NoError(t, err, "Failed to generate OAuth access token")
 
 		// Verify with the second service should fail due to different keys
-		_, err = service2.VerifyOauthAccessToken(tokenString)
+		_, err = service2.VerifyOAuthAccessToken(tokenString)
 		require.Error(t, err, "Verification should fail with invalid signature")
 		assert.Contains(t, err.Error(), "verification error", "Error message should indicate token verification failure")
 	})
@@ -1032,12 +1032,12 @@ func TestGenerateVerifyOauthAccessToken(t *testing.T) {
 		const clientID = "eddsa-oauth-client"
 
 		// Generate a token
-		tokenString, err := service.GenerateOauthAccessToken(user, clientID)
+		tokenString, err := service.GenerateOAuthAccessToken(user, clientID)
 		require.NoError(t, err, "Failed to generate OAuth access token with key")
 		assert.NotEmpty(t, tokenString, "Token should not be empty")
 
 		// Verify the token
-		claims, err := service.VerifyOauthAccessToken(tokenString)
+		claims, err := service.VerifyOAuthAccessToken(tokenString)
 		require.NoError(t, err, "Failed to verify generated OAuth access token with key")
 
 		// Check the claims
@@ -1086,12 +1086,12 @@ func TestGenerateVerifyOauthAccessToken(t *testing.T) {
 		const clientID = "ecdsa-oauth-client"
 
 		// Generate a token
-		tokenString, err := service.GenerateOauthAccessToken(user, clientID)
+		tokenString, err := service.GenerateOAuthAccessToken(user, clientID)
 		require.NoError(t, err, "Failed to generate OAuth access token with key")
 		assert.NotEmpty(t, tokenString, "Token should not be empty")
 
 		// Verify the token
-		claims, err := service.VerifyOauthAccessToken(tokenString)
+		claims, err := service.VerifyOAuthAccessToken(tokenString)
 		require.NoError(t, err, "Failed to verify generated OAuth access token with key")
 
 		// Check the claims
@@ -1140,12 +1140,12 @@ func TestGenerateVerifyOauthAccessToken(t *testing.T) {
 		const clientID = "rsa-oauth-client"
 
 		// Generate a token
-		tokenString, err := service.GenerateOauthAccessToken(user, clientID)
+		tokenString, err := service.GenerateOAuthAccessToken(user, clientID)
 		require.NoError(t, err, "Failed to generate OAuth access token with key")
 		assert.NotEmpty(t, tokenString, "Token should not be empty")
 
 		// Verify the token
-		claims, err := service.VerifyOauthAccessToken(tokenString)
+		claims, err := service.VerifyOAuthAccessToken(tokenString)
 		require.NoError(t, err, "Failed to verify generated OAuth access token with key")
 
 		// Check the claims
@@ -1168,6 +1168,92 @@ func TestGenerateVerifyOauthAccessToken(t *testing.T) {
 	})
 }
 
+func TestGenerateVerifyOAuthRefreshToken(t *testing.T) {
+	// Create a temporary directory for the test
+	tempDir := t.TempDir()
+
+	// Initialize the JWT service with a mock AppConfigService
+	mockConfig := NewTestAppConfigService(&model.AppConfig{})
+
+	// Setup the environment variable required by the token verification
+	originalAppURL := common.EnvConfig.AppURL
+	common.EnvConfig.AppURL = "https://test.example.com"
+	defer func() {
+		common.EnvConfig.AppURL = originalAppURL
+	}()
+
+	t.Run("generates and verifies refresh token", func(t *testing.T) {
+		// Create a JWT service
+		service := &JwtService{}
+		err := service.init(mockConfig, tempDir)
+		require.NoError(t, err, "Failed to initialize JWT service")
+
+		// Create a test user
+		const (
+			userID       = "user123"
+			clientID     = "client123"
+			refreshToken = "rt-123"
+		)
+
+		// Generate a token
+		tokenString, err := service.GenerateOAuthRefreshToken(userID, clientID, refreshToken)
+		require.NoError(t, err, "Failed to generate refresh token")
+		assert.NotEmpty(t, tokenString, "Token should not be empty")
+
+		// Verify the token
+		resUser, resClient, resRT, err := service.VerifyOAuthRefreshToken(tokenString)
+		require.NoError(t, err, "Failed to verify generated token")
+		assert.Equal(t, userID, resUser, "Should return correct user ID")
+		assert.Equal(t, clientID, resClient, "Should return correct client ID")
+		assert.Equal(t, refreshToken, resRT, "Should return correct refresh token")
+	})
+
+	t.Run("fails verification for expired token", func(t *testing.T) {
+		// Create a JWT service
+		service := &JwtService{}
+		err := service.init(mockConfig, tempDir)
+		require.NoError(t, err, "Failed to initialize JWT service")
+
+		// Generate a token using JWT directly to create an expired token
+		token, err := jwt.NewBuilder().
+			Subject("user789").
+			Expiration(time.Now().Add(-1 * time.Hour)). // Expired 1 hour ago
+			IssuedAt(time.Now().Add(-2 * time.Hour)).
+			Audience([]string{"client123"}).
+			Issuer(common.EnvConfig.AppURL).
+			Build()
+		require.NoError(t, err, "Failed to build token")
+
+		signed, err := jwt.Sign(token, jwt.WithKey(jwa.RS256(), service.privateKey))
+		require.NoError(t, err, "Failed to sign token")
+
+		// Verify should fail due to expiration
+		_, _, _, err = service.VerifyOAuthRefreshToken(string(signed))
+		require.Error(t, err, "Verification should fail with expired token")
+		assert.Contains(t, err.Error(), `"exp" not satisfied`, "Error message should indicate token verification failure")
+	})
+
+	t.Run("fails verification with invalid signature", func(t *testing.T) {
+		// Create two JWT services with different keys
+		service1 := &JwtService{}
+		err := service1.init(mockConfig, t.TempDir())
+		require.NoError(t, err, "Failed to initialize first JWT service")
+
+		service2 := &JwtService{}
+		err = service2.init(mockConfig, t.TempDir())
+		require.NoError(t, err, "Failed to initialize second JWT service")
+
+		// Generate a token with the first service
+		tokenString, err := service1.GenerateOAuthRefreshToken("user789", "client123", "my-rt-123")
+		require.NoError(t, err, "Failed to generate refresh token")
+
+		// Verify with the second service should fail due to different keys
+		_, _, _, err = service2.VerifyOAuthRefreshToken(tokenString)
+		require.Error(t, err, "Verification should fail with invalid signature")
+		assert.Contains(t, err.Error(), "verification error", "Error message should indicate token verification failure")
+	})
+}
+
 func TestTokenTypeValidator(t *testing.T) {
 	// Create a context for the validator function
 	ctx := context.Background()
@@ -1213,7 +1299,104 @@ func TestTokenTypeValidator(t *testing.T) {
 		require.Error(t, err, "Validator should reject token without type claim")
 		assert.Contains(t, err.Error(), "failed to get token type claim")
 	})
+}
 
+func TestGetTokenType(t *testing.T) {
+	// Create a temporary directory for the test
+	tempDir := t.TempDir()
+
+	// Initialize the JWT service
+	mockConfig := NewTestAppConfigService(&model.AppConfig{})
+	service := &JwtService{}
+	err := service.init(mockConfig, tempDir)
+	require.NoError(t, err, "Failed to initialize JWT service")
+
+	buildTokenForType := func(t *testing.T, typ string, setClaimsFn func(b *jwt.Builder)) string {
+		t.Helper()
+
+		b := jwt.NewBuilder()
+		b.Subject("user123")
+		if setClaimsFn != nil {
+			setClaimsFn(b)
+		}
+
+		token, err := b.Build()
+		require.NoError(t, err, "Failed to build token")
+
+		err = SetTokenType(token, typ)
+		require.NoError(t, err, "Failed to set token type")
+
+		alg, _ := service.privateKey.Algorithm()
+		signed, err := jwt.Sign(token, jwt.WithKey(alg, service.privateKey))
+		require.NoError(t, err, "Failed to sign token")
+
+		return string(signed)
+	}
+
+	t.Run("correctly identifies access tokens", func(t *testing.T) {
+		tokenString := buildTokenForType(t, AccessTokenJWTType, nil)
+
+		// Get the token type without validating
+		tokenType, _, err := service.GetTokenType(tokenString)
+		require.NoError(t, err, "GetTokenType should not return an error")
+		assert.Equal(t, AccessTokenJWTType, tokenType, "Token type should be correctly identified as access token")
+	})
+
+	t.Run("correctly identifies ID tokens", func(t *testing.T) {
+		tokenString := buildTokenForType(t, IDTokenJWTType, nil)
+
+		// Get the token type without validating
+		tokenType, _, err := service.GetTokenType(tokenString)
+		require.NoError(t, err, "GetTokenType should not return an error")
+		assert.Equal(t, IDTokenJWTType, tokenType, "Token type should be correctly identified as ID token")
+	})
+
+	t.Run("correctly identifies OAuth access tokens", func(t *testing.T) {
+		tokenString := buildTokenForType(t, OAuthAccessTokenJWTType, nil)
+
+		// Get the token type without validating
+		tokenType, _, err := service.GetTokenType(tokenString)
+		require.NoError(t, err, "GetTokenType should not return an error")
+		assert.Equal(t, OAuthAccessTokenJWTType, tokenType, "Token type should be correctly identified as OAuth access token")
+	})
+
+	t.Run("correctly identifies refresh tokens", func(t *testing.T) {
+		tokenString := buildTokenForType(t, OAuthRefreshTokenJWTType, nil)
+
+		// Get the token type without validating
+		tokenType, _, err := service.GetTokenType(tokenString)
+		require.NoError(t, err, "GetTokenType should not return an error")
+		assert.Equal(t, OAuthRefreshTokenJWTType, tokenType, "Token type should be correctly identified as refresh token")
+	})
+
+	t.Run("works with expired tokens", func(t *testing.T) {
+		tokenString := buildTokenForType(t, AccessTokenJWTType, func(b *jwt.Builder) {
+			b.Expiration(time.Now().Add(-1 * time.Hour)) // Expired 1 hour ago
+		})
+
+		// Get the token type without validating
+		tokenType, _, err := service.GetTokenType(tokenString)
+		require.NoError(t, err, "GetTokenType should not return an error for expired tokens")
+		assert.Equal(t, AccessTokenJWTType, tokenType, "Token type should be correctly identified even for expired tokens")
+	})
+
+	t.Run("returns error for malformed tokens", func(t *testing.T) {
+		// Try to get the token type of a malformed token
+		tokenType, _, err := service.GetTokenType("not.a.valid.jwt.token")
+		require.Error(t, err, "GetTokenType should return an error for malformed tokens")
+		assert.Empty(t, tokenType, "Token type should be empty for malformed tokens")
+	})
+
+	t.Run("returns error for tokens without type claim", func(t *testing.T) {
+		// Create a token without type claim
+		tokenString := buildTokenForType(t, "", nil)
+
+		// Get the token type without validating
+		tokenType, _, err := service.GetTokenType(tokenString)
+		require.Error(t, err, "GetTokenType should return an error for tokens without type claim")
+		assert.Empty(t, tokenType, "Token type should be empty when type claim is missing")
+		assert.Contains(t, err.Error(), "failed to get token type claim", "Error message should indicate missing token type claim")
+	})
 }
 
 func importKey(t *testing.T, privateKeyRaw any, path string) string {

backend/internal/service/oidc_service.go

@@ -40,6 +40,9 @@ const (
 	GrantTypeDeviceCode        = "urn:ietf:params:oauth:grant-type:device_code"
 
 	ClientAssertionTypeJWTBearer = "urn:ietf:params:oauth:client-assertion-type:jwt-bearer" //nolint:gosec
+
+	RefreshTokenDuration = 30 * 24 * time.Hour // 30 days
+	DeviceCodeDuration   = 15 * time.Minute
 )
 
 type OidcService struct {
@@ -252,7 +255,7 @@ func (s *OidcService) createTokenFromDeviceCode(ctx context.Context, input dto.O
 		tx.Rollback()
 	}()
 
-	_, err := s.verifyClientCredentialsInternal(ctx, tx, input)
+	_, err := s.verifyClientCredentialsInternal(ctx, tx, clientAuthCredentialsFromCreateTokensDto(&input))
 	if err != nil {
 		return CreatedTokens{}, err
 	}
@@ -303,7 +306,7 @@ func (s *OidcService) createTokenFromDeviceCode(ctx context.Context, input dto.O
 		return CreatedTokens{}, err
 	}
 
-	accessToken, err := s.jwtService.GenerateOauthAccessToken(deviceAuth.User, input.ClientID)
+	accessToken, err := s.jwtService.GenerateOAuthAccessToken(deviceAuth.User, input.ClientID)
 	if err != nil {
 		return CreatedTokens{}, err
 	}
@@ -333,7 +336,7 @@ func (s *OidcService) createTokenFromAuthorizationCode(ctx context.Context, inpu
 		tx.Rollback()
 	}()
 
-	client, err := s.verifyClientCredentialsInternal(ctx, tx, input)
+	client, err := s.verifyClientCredentialsInternal(ctx, tx, clientAuthCredentialsFromCreateTokensDto(&input))
 	if err != nil {
 		return CreatedTokens{}, err
 	}
@@ -375,7 +378,7 @@ func (s *OidcService) createTokenFromAuthorizationCode(ctx context.Context, inpu
 		return CreatedTokens{}, err
 	}
 
-	accessToken, err := s.jwtService.GenerateOauthAccessToken(authorizationCodeMetaData.User, input.ClientID)
+	accessToken, err := s.jwtService.GenerateOAuthAccessToken(authorizationCodeMetaData.User, input.ClientID)
 	if err != nil {
 		return CreatedTokens{}, err
 	}
@@ -406,22 +409,39 @@ func (s *OidcService) createTokenFromRefreshToken(ctx context.Context, input dto
 		return CreatedTokens{}, &common.OidcMissingRefreshTokenError{}
 	}
 
+	// Validate the signed refresh token and extract the actual token (which is a claim in the signed one)
+	userID, clientID, rt, err := s.jwtService.VerifyOAuthRefreshToken(input.RefreshToken)
+	if err != nil {
+		return CreatedTokens{}, &common.OidcInvalidRefreshTokenError{}
+	}
+
 	tx := s.db.Begin()
 	defer func() {
 		tx.Rollback()
 	}()
 
-	_, err := s.verifyClientCredentialsInternal(ctx, tx, input)
+	client, err := s.verifyClientCredentialsInternal(ctx, tx, clientAuthCredentialsFromCreateTokensDto(&input))
 	if err != nil {
 		return CreatedTokens{}, err
 	}
 
+	// The ID of the client that made the call must match the client ID in the token
+	if client.ID != clientID {
+		return CreatedTokens{}, &common.OidcInvalidRefreshTokenError{}
+	}
+
 	// Verify refresh token
 	var storedRefreshToken model.OidcRefreshToken
 	err = tx.
 		WithContext(ctx).
 		Preload("User").
-		Where("token = ? AND expires_at > ?", utils.CreateSha256Hash(input.RefreshToken), datatype.DateTime(time.Now())).
+		Where(
+			"token = ? AND expires_at > ? AND user_id = ? AND client_id = ?",
+			utils.CreateSha256Hash(rt),
+			datatype.DateTime(time.Now()),
+			userID,
+			input.ClientID,
+		).
 		First(&storedRefreshToken).
 		Error
 	if err != nil {
@@ -437,7 +457,7 @@ func (s *OidcService) createTokenFromRefreshToken(ctx context.Context, input dto
 	}
 
 	// Generate a new access token
-	accessToken, err := s.jwtService.GenerateOauthAccessToken(storedRefreshToken.User, input.ClientID)
+	accessToken, err := s.jwtService.GenerateOAuthAccessToken(storedRefreshToken.User, input.ClientID)
 	if err != nil {
 		return CreatedTokens{}, err
 	}
@@ -469,33 +489,69 @@ func (s *OidcService) createTokenFromRefreshToken(ctx context.Context, input dto
 	}, nil
 }
 
-func (s *OidcService) IntrospectToken(ctx context.Context, clientID, clientSecret, tokenString string) (introspectDto dto.OidcIntrospectionResponseDto, err error) {
-	if clientID == "" || clientSecret == "" {
+func (s *OidcService) IntrospectToken(ctx context.Context, creds ClientAuthCredentials, tokenString string) (introspectDto dto.OidcIntrospectionResponseDto, err error) {
+	// Get the type of the token and the client ID
+	tokenType, token, err := s.jwtService.GetTokenType(tokenString)
+	if err != nil {
+		// We just treat the token as invalid
+		introspectDto.Active = false
+		return introspectDto, nil //nolint:nilerr
+	}
+
+	// If we don't have a client ID, get it from the token
+	// Otherwise, we need to make sure that the client ID passed as credential matches
+	tokenAudiences, _ := token.Audience()
+	if len(tokenAudiences) != 1 || tokenAudiences[0] == "" {
+		// We just treat the token as invalid
+		introspectDto.Active = false
+		return introspectDto, nil
+	}
+	if creds.ClientID == "" {
+		creds.ClientID = tokenAudiences[0]
+	} else if creds.ClientID != tokenAudiences[0] {
 		return introspectDto, &common.OidcMissingClientCredentialsError{}
 	}
 
-	_, err = s.verifyClientCredentialsInternal(ctx, s.db, dto.OidcCreateTokensDto{
-		ClientID:     clientID,
-		ClientSecret: clientSecret,
-	})
+	// Verify the credentials for the call
+	client, err := s.verifyClientCredentialsInternal(ctx, s.db, creds)
 	if err != nil {
 		return introspectDto, err
 	}
 
-	token, err := s.jwtService.VerifyOauthAccessToken(tokenString)
-	if err != nil {
-		if errors.Is(err, jwt.ParseError()) {
-			// It's apparently not a valid JWT token, so we check if it's a valid refresh_token.
-			return s.introspectRefreshToken(ctx, tokenString)
-		}
-
-		// Every failure we get means the token is invalid. Nothing more to do with the error.
+	// Introspect the token
+	switch tokenType {
+	case OAuthAccessTokenJWTType:
+		return s.introspectAccessToken(client.ID, tokenString)
+	case OAuthRefreshTokenJWTType:
+		return s.introspectRefreshToken(ctx, client.ID, tokenString)
+	default:
+		// We just treat the token as invalid
 		introspectDto.Active = false
 		return introspectDto, nil
 	}
+}
+
+func (s *OidcService) introspectAccessToken(clientID string, tokenString string) (introspectDto dto.OidcIntrospectionResponseDto, err error) {
+	token, err := s.jwtService.VerifyOAuthAccessToken(tokenString)
+	if err != nil {
+		// Every failure we get means the token is invalid. Nothing more to do with the error.
+		introspectDto.Active = false
+		return introspectDto, nil //nolint:nilerr
+	}
+
+	// The ID of the client that made the request must match the client ID in the token
+	audience, ok := token.Audience()
+	if !ok || len(audience) != 1 || audience[0] == "" {
+		introspectDto.Active = false
+		return introspectDto, nil
+	}
+	if audience[0] != clientID {
+		return introspectDto, &common.OidcMissingClientCredentialsError{}
+	}
 
 	introspectDto.Active = true
 	introspectDto.TokenType = "access_token"
+	introspectDto.Audience = audience
 	if token.Has("scope") {
 		var (
 			asString  string
@@ -519,9 +575,6 @@ func (s *OidcService) IntrospectToken(ctx context.Context, clientID, clientSecre
 	if subject, ok := token.Subject(); ok {
 		introspectDto.Subject = subject
 	}
-	if audience, ok := token.Audience(); ok {
-		introspectDto.Audience = audience
-	}
 	if issuer, ok := token.Issuer(); ok {
 		introspectDto.Issuer = issuer
 	}
@@ -532,12 +585,29 @@ func (s *OidcService) IntrospectToken(ctx context.Context, clientID, clientSecre
 	return introspectDto, nil
 }
 
-func (s *OidcService) introspectRefreshToken(ctx context.Context, refreshToken string) (introspectDto dto.OidcIntrospectionResponseDto, err error) {
+func (s *OidcService) introspectRefreshToken(ctx context.Context, clientID string, refreshToken string) (introspectDto dto.OidcIntrospectionResponseDto, err error) {
+	// Validate the signed refresh token and extract the actual token (which is a claim in the signed one)
+	tokenUserID, tokenClientID, tokenRT, err := s.jwtService.VerifyOAuthRefreshToken(refreshToken)
+	if err != nil {
+		return introspectDto, fmt.Errorf("invalid refresh token: %w", err)
+	}
+
+	// The ID of the client that made the call must match the client ID in the token
+	if tokenClientID != clientID {
+		return introspectDto, errors.New("invalid refresh token: client ID does not match")
+	}
+
 	var storedRefreshToken model.OidcRefreshToken
 	err = s.db.
 		WithContext(ctx).
 		Preload("User").
-		Where("token = ? AND expires_at > ?", utils.CreateSha256Hash(refreshToken), datatype.DateTime(time.Now())).
+		Where(
+			"token = ? AND expires_at > ? AND user_id = ? AND client_id = ?",
+			utils.CreateSha256Hash(tokenRT),
+			datatype.DateTime(time.Now()),
+			tokenUserID,
+			tokenClientID,
+		).
 		First(&storedRefreshToken).
 		Error
 	if err != nil {
@@ -1062,9 +1132,11 @@ func (s *OidcService) addCallbackURLToClient(ctx context.Context, client *model.
 }
 
 func (s *OidcService) CreateDeviceAuthorization(ctx context.Context, input dto.OidcDeviceAuthorizationRequestDto) (*dto.OidcDeviceAuthorizationResponseDto, error) {
-	client, err := s.verifyClientCredentialsInternal(ctx, s.db, dto.OidcCreateTokensDto{
+	client, err := s.verifyClientCredentialsInternal(ctx, s.db, ClientAuthCredentials{
 		ClientID:            input.ClientID,
 		ClientSecret:        input.ClientSecret,
+		ClientAssertionType: input.ClientAssertionType,
+		ClientAssertion:     input.ClientAssertion,
 	})
 	if err != nil {
 		return nil, err
@@ -1085,7 +1157,7 @@ func (s *OidcService) CreateDeviceAuthorization(ctx context.Context, input dto.O
 		DeviceCode:   deviceCode,
 		UserCode:     userCode,
 		Scope:        input.Scope,
-		ExpiresAt:    datatype.DateTime(time.Now().Add(15 * time.Minute)),
+		ExpiresAt:    datatype.DateTime(time.Now().Add(DeviceCodeDuration)),
 		IsAuthorized: false,
 		ClientID:     client.ID,
 	}
@@ -1099,7 +1171,7 @@ func (s *OidcService) CreateDeviceAuthorization(ctx context.Context, input dto.O
 		UserCode:                userCode,
 		VerificationURI:         common.EnvConfig.AppURL + "/device",
 		VerificationURIComplete: common.EnvConfig.AppURL + "/device?code=" + userCode,
-		ExpiresIn:               900, // 15 minutes
+		ExpiresIn:               int(DeviceCodeDuration.Seconds()),
 		Interval:                5,
 	}, nil
 }
@@ -1255,7 +1327,7 @@ func (s *OidcService) createRefreshToken(ctx context.Context, clientID string, u
 	refreshTokenHash := utils.CreateSha256Hash(refreshToken)
 
 	m := model.OidcRefreshToken{
-		ExpiresAt: datatype.DateTime(time.Now().Add(30 * 24 * time.Hour)), // 30 days
+		ExpiresAt: datatype.DateTime(time.Now().Add(RefreshTokenDuration)),
 		Token:     refreshTokenHash,
 		ClientID:  clientID,
 		UserID:    userID,
@@ -1270,7 +1342,13 @@ func (s *OidcService) createRefreshToken(ctx context.Context, clientID string, u
 		return "", err
 	}
 
-	return refreshToken, nil
+	// Sign the refresh token
+	signed, err := s.jwtService.GenerateOAuthRefreshToken(userID, clientID, refreshToken)
+	if err != nil {
+		return "", fmt.Errorf("failed to sign refresh token: %w", err)
+	}
+
+	return signed, nil
 }
 
 func (s *OidcService) createAuthorizedClientInternal(ctx context.Context, userID string, clientID string, scope string, tx *gorm.DB) error {
@@ -1291,7 +1369,23 @@ func (s *OidcService) createAuthorizedClientInternal(ctx context.Context, userID
 	return err
 }
 
-func (s *OidcService) verifyClientCredentialsInternal(ctx context.Context, tx *gorm.DB, input dto.OidcCreateTokensDto) (*model.OidcClient, error) {
+type ClientAuthCredentials struct {
+	ClientID            string
+	ClientSecret        string
+	ClientAssertion     string
+	ClientAssertionType string
+}
+
+func clientAuthCredentialsFromCreateTokensDto(d *dto.OidcCreateTokensDto) ClientAuthCredentials {
+	return ClientAuthCredentials{
+		ClientID:            d.ClientID,
+		ClientSecret:        d.ClientSecret,
+		ClientAssertion:     d.ClientAssertion,
+		ClientAssertionType: d.ClientAssertionType,
+	}
+}
+
+func (s *OidcService) verifyClientCredentialsInternal(ctx context.Context, tx *gorm.DB, input ClientAuthCredentials) (*model.OidcClient, error) {
 	// First, ensure we have a valid client ID
 	if input.ClientID == "" {
 		return nil, &common.OidcMissingClientCredentialsError{}
@@ -1366,7 +1460,7 @@ func (s *OidcService) jwkSetForURL(ctx context.Context, url string) (set jwk.Set
 	return jwks, nil
 }
 
-func (s *OidcService) verifyClientAssertionFromFederatedIdentities(ctx context.Context, client *model.OidcClient, input dto.OidcCreateTokensDto) error {
+func (s *OidcService) verifyClientAssertionFromFederatedIdentities(ctx context.Context, client *model.OidcClient, input ClientAuthCredentials) error {
 	// First, parse the assertion JWT, without validating it, to check the issuer
 	assertion := []byte(input.ClientAssertion)
 	insecureToken, err := jwt.ParseInsecure(assertion)
@@ -1466,12 +1560,18 @@ func (s *OidcService) GetClientPreview(ctx context.Context, clientID string, use
 		return nil, err
 	}
 
+	// Commit the transaction before signing tokens to avoid locking the database for longer
+	err = tx.Commit().Error
+	if err != nil {
+		return nil, err
+	}
+
 	idToken, err := s.jwtService.BuildIDToken(userClaims, clientID, "")
 	if err != nil {
 		return nil, err
 	}
 
-	accessToken, err := s.jwtService.BuildOauthAccessToken(user, clientID)
+	accessToken, err := s.jwtService.BuildOAuthAccessToken(user, clientID)
 	if err != nil {
 		return nil, err
 	}
@@ -1486,11 +1586,6 @@ func (s *OidcService) GetClientPreview(ctx context.Context, clientID string, use
 		return nil, err
 	}
 
-	err = tx.Commit().Error
-	if err != nil {
-		return nil, err
-	}
-
 	return &dto.OidcClientPreviewDto{
 		IdToken:     idTokenPayload,
 		AccessToken: accessTokenPayload,
@@ -1498,26 +1593,11 @@ func (s *OidcService) GetClientPreview(ctx context.Context, clientID string, use
 	}, nil
 }
 
-func (s *OidcService) GetUserClaimsForClient(ctx context.Context, userID string, clientID string) (map[string]interface{}, error) {
-	tx := s.db.Begin()
-	defer func() {
-		tx.Rollback()
-	}()
-
-	claims, err := s.getUserClaimsForClientInternal(ctx, userID, clientID, s.db)
-	if err != nil {
-		return nil, err
-	}
-
-	err = tx.Commit().Error
-	if err != nil {
-		return nil, err
-	}
-
-	return claims, nil
+func (s *OidcService) GetUserClaimsForClient(ctx context.Context, userID string, clientID string) (map[string]any, error) {
+	return s.getUserClaimsForClientInternal(ctx, userID, clientID, s.db)
 }
 
-func (s *OidcService) getUserClaimsForClientInternal(ctx context.Context, userID string, clientID string, tx *gorm.DB) (map[string]interface{}, error) {
+func (s *OidcService) getUserClaimsForClientInternal(ctx context.Context, userID string, clientID string, tx *gorm.DB) (map[string]any, error) {
 	var authorizedOidcClient model.UserAuthorizedOidcClient
 	err := tx.
 		WithContext(ctx).
@@ -1532,14 +1612,13 @@ func (s *OidcService) getUserClaimsForClientInternal(ctx context.Context, userID
 
 }
 
-func (s *OidcService) getUserClaimsFromAuthorizedClient(ctx context.Context, authorizedClient *model.UserAuthorizedOidcClient, tx *gorm.DB) (map[string]interface{}, error) {
+func (s *OidcService) getUserClaimsFromAuthorizedClient(ctx context.Context, authorizedClient *model.UserAuthorizedOidcClient, tx *gorm.DB) (map[string]any, error) {
 	user := authorizedClient.User
 	scopes := strings.Split(authorizedClient.Scope, " ")
 
-	claims := map[string]interface{}{
-		"sub": user.ID,
-	}
+	claims := make(map[string]any, 10)
 
+	claims["sub"] = user.ID
 	if slices.Contains(scopes, "email") {
 		claims["email"] = user.Email
 		claims["email_verified"] = s.appConfigService.GetDbConfig().EmailsVerified.IsTrue()
@@ -1553,19 +1632,13 @@ func (s *OidcService) getUserClaimsFromAuthorizedClient(ctx context.Context, aut
 		claims["groups"] = userGroups
 	}
 
-	profileClaims := map[string]interface{}{
-		"given_name":         user.FirstName,
-		"family_name":        user.LastName,
-		"name":               user.FullName(),
-		"preferred_username": user.Username,
-		"picture":            common.EnvConfig.AppURL + "/api/users/" + user.ID + "/profile-picture.png",
-	}
-
 	if slices.Contains(scopes, "profile") {
 		// Add profile claims
-		for k, v := range profileClaims {
-			claims[k] = v
-		}
+		claims["given_name"] = user.FirstName
+		claims["family_name"] = user.LastName
+		claims["name"] = user.FullName()
+		claims["preferred_username"] = user.Username
+		claims["picture"] = common.EnvConfig.AppURL + "/api/users/" + user.ID + "/profile-picture.png"
 
 		// Add custom claims
 		customClaims, err := s.customClaimService.GetCustomClaimsForUserWithUserGroups(ctx, user.ID, tx)
@@ -1575,7 +1648,7 @@ func (s *OidcService) getUserClaimsFromAuthorizedClient(ctx context.Context, aut
 
 		for _, customClaim := range customClaims {
 			// The value of the custom claim can be a JSON object or a string
-			var jsonValue interface{}
+			var jsonValue any
 			err := json.Unmarshal([]byte(customClaim.Value), &jsonValue)
 			if err == nil {
 				// It's JSON, so we store it as an object

backend/internal/service/oidc_service_test.go

@@ -210,7 +210,7 @@ func TestOidcService_verifyClientCredentialsInternal(t *testing.T) {
 	t.Run("Confidential client", func(t *testing.T) {
 		t.Run("Succeeds with valid secret", func(t *testing.T) {
 			// Test with valid client credentials
-			client, err := s.verifyClientCredentialsInternal(t.Context(), s.db, dto.OidcCreateTokensDto{
+			client, err := s.verifyClientCredentialsInternal(t.Context(), s.db, ClientAuthCredentials{
 				ClientID:     confidentialClient.ID,
 				ClientSecret: confidentialSecret,
 			})
@@ -221,7 +221,7 @@ func TestOidcService_verifyClientCredentialsInternal(t *testing.T) {
 
 		t.Run("Fails with invalid secret", func(t *testing.T) {
 			// Test with invalid client secret
-			client, err := s.verifyClientCredentialsInternal(t.Context(), s.db, dto.OidcCreateTokensDto{
+			client, err := s.verifyClientCredentialsInternal(t.Context(), s.db, ClientAuthCredentials{
 				ClientID:     confidentialClient.ID,
 				ClientSecret: "invalid-secret",
 			})
@@ -232,7 +232,7 @@ func TestOidcService_verifyClientCredentialsInternal(t *testing.T) {
 
 		t.Run("Fails with missing secret", func(t *testing.T) {
 			// Test with missing client secret
-			client, err := s.verifyClientCredentialsInternal(t.Context(), s.db, dto.OidcCreateTokensDto{
+			client, err := s.verifyClientCredentialsInternal(t.Context(), s.db, ClientAuthCredentials{
 				ClientID: confidentialClient.ID,
 			})
 			require.Error(t, err)
@@ -245,7 +245,7 @@ func TestOidcService_verifyClientCredentialsInternal(t *testing.T) {
 	t.Run("Public client", func(t *testing.T) {
 		t.Run("Succeeds with no credentials", func(t *testing.T) {
 			// Public clients don't require client secret
-			client, err := s.verifyClientCredentialsInternal(t.Context(), s.db, dto.OidcCreateTokensDto{
+			client, err := s.verifyClientCredentialsInternal(t.Context(), s.db, ClientAuthCredentials{
 				ClientID: publicClient.ID,
 			})
 			require.NoError(t, err)
@@ -270,7 +270,7 @@ func TestOidcService_verifyClientCredentialsInternal(t *testing.T) {
 			require.NoError(t, err)
 
 			// Test with valid JWT assertion
-			client, err := s.verifyClientCredentialsInternal(t.Context(), s.db, dto.OidcCreateTokensDto{
+			client, err := s.verifyClientCredentialsInternal(t.Context(), s.db, ClientAuthCredentials{
 				ClientID:            federatedClient.ID,
 				ClientAssertionType: ClientAssertionTypeJWTBearer,
 				ClientAssertion:     string(signedToken),
@@ -282,7 +282,7 @@ func TestOidcService_verifyClientCredentialsInternal(t *testing.T) {
 
 		t.Run("Fails with malformed JWT", func(t *testing.T) {
 			// Test with invalid JWT assertion (just a random string)
-			client, err := s.verifyClientCredentialsInternal(t.Context(), s.db, dto.OidcCreateTokensDto{
+			client, err := s.verifyClientCredentialsInternal(t.Context(), s.db, ClientAuthCredentials{
 				ClientID:            federatedClient.ID,
 				ClientAssertionType: ClientAssertionTypeJWTBearer,
 				ClientAssertion:     "invalid.jwt.token",
@@ -311,7 +311,7 @@ func TestOidcService_verifyClientCredentialsInternal(t *testing.T) {
 				require.NoError(t, err)
 
 				// Test with invalid JWT assertion
-				client, err := s.verifyClientCredentialsInternal(t.Context(), s.db, dto.OidcCreateTokensDto{
+				client, err := s.verifyClientCredentialsInternal(t.Context(), s.db, ClientAuthCredentials{
 					ClientID:            federatedClient.ID,
 					ClientAssertionType: ClientAssertionTypeJWTBearer,
 					ClientAssertion:     string(signedToken),
@@ -352,7 +352,7 @@ func TestOidcService_verifyClientCredentialsInternal(t *testing.T) {
 			require.NoError(t, err)
 
 			// Test with valid JWT assertion
-			client, err := s.verifyClientCredentialsInternal(t.Context(), s.db, dto.OidcCreateTokensDto{
+			client, err := s.verifyClientCredentialsInternal(t.Context(), s.db, ClientAuthCredentials{
 				ClientID:            federatedClient.ID,
 				ClientAssertionType: ClientAssertionTypeJWTBearer,
 				ClientAssertion:     string(signedToken),

backend/internal/utils/http_util.go

@@ -0,0 +1,18 @@
+package utils
+
+import (
+	"net/http"
+	"strings"
+)
+
+// BearerAuth returns the value of the bearer token in the Authorization header if present
+func BearerAuth(r *http.Request) (string, bool) {
+	const prefix = "bearer "
+
+	authHeader := r.Header.Get("Authorization")
+	if len(authHeader) >= len(prefix) && strings.ToLower(authHeader[:len(prefix)]) == prefix {
+		return authHeader[len(prefix):], true
+	}
+
+	return "", false
+}

backend/internal/utils/http_util_test.go

@@ -0,0 +1,65 @@
+package utils
+
+import (
+	"net/http"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func TestBearerAuth(t *testing.T) {
+	tests := []struct {
+		name          string
+		authHeader    string
+		expectedToken string
+		expectedFound bool
+	}{
+		{
+			name:          "Valid bearer token",
+			authHeader:    "Bearer token123",
+			expectedToken: "token123",
+			expectedFound: true,
+		},
+		{
+			name:          "Valid bearer token with mixed case",
+			authHeader:    "beARer token456",
+			expectedToken: "token456",
+			expectedFound: true,
+		},
+		{
+			name:          "No bearer prefix",
+			authHeader:    "Basic dXNlcjpwYXNz",
+			expectedToken: "",
+			expectedFound: false,
+		},
+		{
+			name:          "Empty auth header",
+			authHeader:    "",
+			expectedToken: "",
+			expectedFound: false,
+		},
+		{
+			name:          "Bearer prefix only",
+			authHeader:    "Bearer ",
+			expectedToken: "",
+			expectedFound: true,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			req, err := http.NewRequestWithContext(t.Context(), http.MethodGet, "http://example.com", nil)
+			require.NoError(t, err, "Failed to create request")
+
+			if tt.authHeader != "" {
+				req.Header.Set("Authorization", tt.authHeader)
+			}
+
+			token, found := BearerAuth(req)
+
+			assert.Equal(t, tt.expectedFound, found)
+			assert.Equal(t, tt.expectedToken, token)
+		})
+	}
+}

backend/internal/utils/jwt_util.go

@@ -7,8 +7,9 @@ import (
 )
 
 func GetClaimsFromToken(token jwt.Token) (map[string]any, error) {
-	claims := make(map[string]any)
-	for _, key := range token.Keys() {
+	keys := token.Keys()
+	claims := make(map[string]any, len(keys))
+	for _, key := range keys {
 		var value any
 		if err := token.Get(key, &value); err != nil {
 			return nil, fmt.Errorf("failed to get claim %s: %w", key, err)

tests/data.ts

@@ -87,11 +87,13 @@ export const refreshTokens = [
 	{
 		token: 'ou87UDg249r1StBLYkMEqy9TXDbV5HmGuDpMcZDo',
 		clientId: oidcClients.nextcloud.id,
+		userId: 'f4b89dc2-62fb-46bf-9f5f-c34f4eafe93e',
 		expired: false
 	},
 	{
 		token: 'X4vqwtRyCUaq51UafHea4Fsg8Km6CAns6vp3tuX4',
 		clientId: oidcClients.nextcloud.id,
+		userId: 'f4b89dc2-62fb-46bf-9f5f-c34f4eafe93e',
 		expired: true
 	}
 ];

tests/specs/oidc.spec.ts

@@ -156,11 +156,21 @@ test("End session with id token hint redirects to callback URL", async ({
 test("Successfully refresh tokens with valid refresh token", async ({
   request,
 }) => {
-  const { token, clientId } = refreshTokens.filter(
+  const { token, clientId, userId } = refreshTokens.filter(
     (token) => !token.expired
   )[0];
   const clientSecret = "w2mUeZISmEvIDMEDvpY0PnxQIpj1m3zY";
 
+  // Sign the refresh token
+  const refreshToken = await request.post("/api/test/refreshtoken", {
+    data: {
+      rt: token,
+      client: clientId,
+      user: userId,
+    }
+  }).then((r) => r.text())
+
+  // Perform the exchange
   const refreshResponse = await request.post("/api/oidc/token", {
     headers: {
       "Content-Type": "application/x-www-form-urlencoded",
@@ -168,7 +178,7 @@ test("Successfully refresh tokens with valid refresh token", async ({
     form: {
       grant_type: "refresh_token",
       client_id: clientId,
-      refresh_token: token,
+      refresh_token: refreshToken,
       client_secret: clientSecret,
     },
   });
@@ -184,26 +194,25 @@ test("Successfully refresh tokens with valid refresh token", async ({
   expect(tokenData.refresh_token).not.toBe(token);
 });
 
-test("Using refresh token invalidates it for future use", async ({
+
+test("Refresh token fails when used for the wrong client", async ({
   request,
 }) => {
-  const { token, clientId } = refreshTokens.filter(
+  const { token, clientId, userId } = refreshTokens.filter(
     (token) => !token.expired
   )[0];
   const clientSecret = "w2mUeZISmEvIDMEDvpY0PnxQIpj1m3zY";
 
-  await request.post("/api/oidc/token", {
-    headers: {
-      "Content-Type": "application/x-www-form-urlencoded",
-    },
-    form: {
-      grant_type: "refresh_token",
-      client_id: clientId,
-      refresh_token: token,
-      client_secret: clientSecret,
-    },
-  });
+  // Sign the refresh token
+  const refreshToken = await request.post("/api/test/refreshtoken", {
+    data: {
+      rt: token,
+      client: 'bad-client',
+      user: userId,
+    }
+  }).then((r) => r.text())
 
+  // Perform the exchange
   const refreshResponse = await request.post("/api/oidc/token", {
     headers: {
       "Content-Type": "application/x-www-form-urlencoded",
@@ -211,7 +220,86 @@ test("Using refresh token invalidates it for future use", async ({
     form: {
       grant_type: "refresh_token",
       client_id: clientId,
-      refresh_token: token,
+      refresh_token: refreshToken,
+      client_secret: clientSecret,
+    },
+  });
+
+  expect(refreshResponse.status()).toBe(400);
+});
+
+test("Refresh token fails when used for the wrong user", async ({
+  request,
+}) => {
+  const { token, clientId } = refreshTokens.filter(
+    (token) => !token.expired
+  )[0];
+  const clientSecret = "w2mUeZISmEvIDMEDvpY0PnxQIpj1m3zY";
+
+  // Sign the refresh token
+  const refreshToken = await request.post("/api/test/refreshtoken", {
+    data: {
+      rt: token,
+      client: clientId,
+      user: 'bad-user',
+    }
+  }).then((r) => r.text())
+
+  // Perform the exchange
+  const refreshResponse = await request.post("/api/oidc/token", {
+    headers: {
+      "Content-Type": "application/x-www-form-urlencoded",
+    },
+    form: {
+      grant_type: "refresh_token",
+      client_id: clientId,
+      refresh_token: refreshToken,
+      client_secret: clientSecret,
+    },
+  });
+
+  expect(refreshResponse.status()).toBe(400);
+});
+
+test("Using refresh token invalidates it for future use", async ({
+  request,
+}) => {
+  const { token, clientId, userId } = refreshTokens.filter(
+    (token) => !token.expired
+  )[0];
+  const clientSecret = "w2mUeZISmEvIDMEDvpY0PnxQIpj1m3zY";
+
+  // Sign the refresh token
+  const refreshToken = await request.post("/api/test/refreshtoken", {
+    data: {
+      rt: token,
+      client: clientId,
+      user: userId,
+    }
+  }).then((r) => r.text())
+
+  // Perform the exchange
+  await request.post("/api/oidc/token", {
+    headers: {
+      "Content-Type": "application/x-www-form-urlencoded",
+    },
+    form: {
+      grant_type: "refresh_token",
+      client_id: clientId,
+      refresh_token: refreshToken,
+      client_secret: clientSecret,
+    },
+  });
+
+  // Try again
+  const refreshResponse = await request.post("/api/oidc/token", {
+    headers: {
+      "Content-Type": "application/x-www-form-urlencoded",
+    },
+    form: {
+      grant_type: "refresh_token",
+      client_id: clientId,
+      refresh_token: refreshToken,
       client_secret: clientSecret,
     },
   });
@@ -219,11 +307,10 @@ test("Using refresh token invalidates it for future use", async ({
 });
 
 test.describe("Introspection endpoint", () => {
-  const client = oidcClients.nextcloud;
-  test("without client_id and client_secret fails", async ({ request }) => {
+  test("fails without client credentials", async ({ request }) => {
     const validAccessToken = await generateOauthAccessToken(
       users.tim,
-      client.id
+      oidcClients.nextcloud.id
     );
     const introspectionResponse = await request.post("/api/oidc/introspect", {
       headers: {
@@ -237,20 +324,20 @@ test.describe("Introspection endpoint", () => {
     expect(introspectionResponse.status()).toBe(400);
   });
 
-  test("with client_id and client_secret succeeds", async ({
+  test("succeeds with client credentials", async ({
     request,
     baseURL,
   }) => {
     const validAccessToken = await generateOauthAccessToken(
       users.tim,
-      client.id
+      oidcClients.nextcloud.id
     );
     const introspectionResponse = await request.post("/api/oidc/introspect", {
       headers: {
         "Content-Type": "application/x-www-form-urlencoded",
         Authorization:
           "Basic " +
-          Buffer.from(`${client.id}:${client.secret}`).toString("base64"),
+          Buffer.from(`${oidcClients.nextcloud.id}:${oidcClients.nextcloud.secret}`).toString("base64"),
       },
       form: {
         token: validAccessToken,
@@ -266,18 +353,102 @@ test.describe("Introspection endpoint", () => {
     expect(introspectionBody.aud).toStrictEqual([oidcClients.nextcloud.id]);
   });
 
+  test("succeeds with federated client credentials", async ({
+    page,
+    request,
+    baseURL,
+  }) => {
+    const validAccessToken = await generateOauthAccessToken(
+      users.tim,
+      oidcClients.federated.id
+    );
+    const clientAssertion = await oidcUtil.getClientAssertion(page, oidcClients.federated.federatedJWT);
+    const introspectionResponse = await request.post("/api/oidc/introspect", {
+      headers: {
+        "Content-Type": "application/x-www-form-urlencoded",
+        Authorization: "Bearer " + clientAssertion,
+      },
+      form: {
+        token: validAccessToken,
+      },
+    });
+
+    expect(introspectionResponse.status()).toBe(200);
+    const introspectionBody = await introspectionResponse.json();
+    expect(introspectionBody.active).toBe(true);
+    expect(introspectionBody.token_type).toBe("access_token");
+    expect(introspectionBody.iss).toBe(baseURL);
+    expect(introspectionBody.sub).toBe(users.tim.id);
+    expect(introspectionBody.aud).toStrictEqual([oidcClients.federated.id]);
+  });
+
+  test("fails with client credentials for wrong app", async ({
+    request,
+  }) => {
+    const validAccessToken = await generateOauthAccessToken(
+      users.tim,
+      oidcClients.nextcloud.id
+    );
+    const introspectionResponse = await request.post("/api/oidc/introspect", {
+      headers: {
+        "Content-Type": "application/x-www-form-urlencoded",
+        Authorization:
+          "Basic " +
+          Buffer.from(`${oidcClients.immich.id}:${oidcClients.immich.secret}`).toString("base64"),
+      },
+      form: {
+        token: validAccessToken,
+      },
+    });
+
+    expect(introspectionResponse.status()).toBe(400);
+  });
+
+  test("fails with federated credentials for wrong app", async ({
+    page,
+    request,
+  }) => {
+    const validAccessToken = await generateOauthAccessToken(
+      users.tim,
+      oidcClients.nextcloud.id
+    );
+    const clientAssertion = await oidcUtil.getClientAssertion(page, oidcClients.federated.federatedJWT);
+    const introspectionResponse = await request.post("/api/oidc/introspect", {
+      headers: {
+        "Content-Type": "application/x-www-form-urlencoded",
+        Authorization: "Bearer " + clientAssertion,
+      },
+      form: {
+        token: validAccessToken,
+      },
+    });
+
+    expect(introspectionResponse.status()).toBe(400);
+  });
+
   test("non-expired refresh_token can be verified", async ({ request }) => {
-    const { token } = refreshTokens.filter((token) => !token.expired)[0];
+    const { token, clientId, userId } = refreshTokens.filter(
+      (token) => !token.expired
+    )[0];
+
+    // Sign the refresh token
+    const refreshToken = await request.post("/api/test/refreshtoken", {
+      data: {
+        rt: token,
+        client: clientId,
+        user: userId,
+      }
+    }).then((r) => r.text())
 
     const introspectionResponse = await request.post("/api/oidc/introspect", {
       headers: {
         "Content-Type": "application/x-www-form-urlencoded",
         Authorization:
           "Basic " +
-          Buffer.from(`${client.id}:${client.secret}`).toString("base64"),
+          Buffer.from(`${oidcClients.nextcloud.id}:${oidcClients.nextcloud.secret}`).toString("base64"),
       },
       form: {
-        token: token,
+        token: refreshToken,
       },
     });
 
@@ -288,17 +459,28 @@ test.describe("Introspection endpoint", () => {
   });
 
   test("expired refresh_token can be verified", async ({ request }) => {
-    const { token } = refreshTokens.filter((token) => token.expired)[0];
+    const { token, clientId, userId } = refreshTokens.filter(
+      (token) => token.expired
+    )[0];
+
+    // Sign the refresh token
+    const refreshToken = await request.post("/api/test/refreshtoken", {
+      data: {
+        rt: token,
+        client: clientId,
+        user: userId,
+      }
+    }).then((r) => r.text())
 
     const introspectionResponse = await request.post("/api/oidc/introspect", {
       headers: {
         "Content-Type": "application/x-www-form-urlencoded",
         Authorization:
           "Basic " +
-          Buffer.from(`${client.id}:${client.secret}`).toString("base64"),
+          Buffer.from(`${oidcClients.nextcloud.id}:${oidcClients.nextcloud.secret}`).toString("base64"),
       },
       form: {
-        token: token,
+        token: refreshToken,
       },
     });
 
@@ -310,7 +492,7 @@ test.describe("Introspection endpoint", () => {
   test("expired access_token can't be verified", async ({ request }) => {
     const expiredAccessToken = await generateOauthAccessToken(
       users.tim,
-      client.id,
+      oidcClients.nextcloud.id,
       true
     );
     const introspectionResponse = await request.post("/api/oidc/introspect", {