public void verifyIdentity()

in extensions/guacamole-auth-totp/src/main/java/org/apache/guacamole/auth/totp/user/UserVerificationService.java [288:369]
50 lines of code
11 McCabe index (conditional complexity)

    public void verifyIdentity(UserContext context,
            AuthenticatedUser authenticatedUser) throws GuacamoleException {

        // Ignore anonymous users
        String username = authenticatedUser.getIdentifier();
        if (username.equals(AuthenticatedUser.ANONYMOUS_IDENTIFIER))
            return;

        // Check if TOTP has been disabled for this user
        if (totpDisabled(context, authenticatedUser))
            return;
        
        // Ignore users which do not have an associated key
        UserTOTPKey key = getKey(context, username);
        if (key == null)
            return;

        // Pull the original HTTP request used to authenticate
        Credentials credentials = authenticatedUser.getCredentials();
        HttpServletRequest request = credentials.getRequest();

        // Retrieve TOTP from request
        String code = request.getParameter(AuthenticationCodeField.PARAMETER_NAME);

        // If no TOTP provided, request one
        if (code == null) {

            AuthenticationCodeField field = codeFieldProvider.get();

            // If the user hasn't completed enrollment, request that they do
            if (!key.isConfirmed()) {
                field.exposeKey(key);
                throw new TranslatableGuacamoleInsufficientCredentialsException(
                        "TOTP enrollment must be completed before "
                        + "authentication can continue",
                        "TOTP.INFO_ENROLL_REQUIRED", new CredentialsInfo(
                            Collections.<Field>singletonList(field)
                        ));
            }

            // Otherwise simply request the user's authentication code
            throw new TranslatableGuacamoleInsufficientCredentialsException(
                    "A TOTP authentication code is required before login can "
                    + "continue", "TOTP.INFO_CODE_REQUIRED", new CredentialsInfo(
                        Collections.<Field>singletonList(field)
                    ));

        }

        try {

            // Get generator based on user's key and provided configuration
            TOTPGenerator totp = new TOTPGenerator(key.getSecret(),
                    confService.getMode(), confService.getDigits(),
                    TOTPGenerator.DEFAULT_START_TIME, confService.getPeriod());

            // Verify provided TOTP against value produced by generator
            if ((code.equals(totp.generate()) || code.equals(totp.previous()))
                    && codeService.useCode(username, code)) {

                // Record key as confirmed, if it hasn't already been so recorded
                if (!key.isConfirmed()) {
                    key.setConfirmed(true);
                    setKey(context, key);
                }

                // User has been verified
                return;

            }

        }
        catch (InvalidKeyException e) {
            logger.warn("User \"{}\" is associated with an invalid TOTP key.", username);
            logger.debug("TOTP key is not valid.", e);
        }

        // Provided code is not valid
        throw new TranslatableGuacamoleClientException("Provided TOTP code "
                + "is not valid.", "TOTP.INFO_VERIFICATION_FAILED");

    }