How to implement a custom password field that redirects to another page upon correct password?

Question

I have a password protected page (Page X), but I need the password form that grants access to Page X to live on the home page.

With the password form on the home page, I want the user to be able to enter the correct password directly. If correct, I want the user to be redirected to the password protected Page X.

Is this possible to implement? Normally, once a user presses on a link that is password protected, they are redirected to the password form that is its own separate page. But I want to cut out this intermediary password form page, and place the form directly on the home page. If you have any tips, please let me know.

I tried using the get_the_password_form function below and passing in the page/post ID. It does return the proper HTML code for a form, and a form is displayed. However, it does not function correctly: does nothing despite entering in the correct password. The function below is from wp-includes folder.

function get_the_password_form( $post = 0 ) {
    $post = get_post( $post );
    $label = 'pwbox-' . ( empty($post->ID) ? rand() : $post->ID );
    $output = '<form action="' . esc_url( site_url( 'wp-login.php?action=postpass', 'login_post' ) ) . '" class="post-password-form" method="post">
    <p>' . __( 'This content is password protected. To view it please enter your password below:' ) . '</p>
    <p><label for="' . $label . '">' . __( 'Password:' ) . ' <input name="post_password" id="' . $label . '" type="password" size="20" /></label> <input type="submit" name="Submit" value="' . esc_attr_x( 'Enter', 'post password form' ) . '" /></p></form>
    ';

    /**
     * Filters the HTML output for the protected post password form.
     *
     * If modifying the password field, please note that the core database schema
     * limits the password field to 20 characters regardless of the value of the
     * size attribute in the form input.
     *
     * @since 2.7.0
     *
     * @param string $output The password form HTML output.
     */
    return apply_filters( 'the_password_form', $output );
}

Answer 1

The problem is that WP will redirect to the referrer when the authentication succeeds.

Fortunately, you can also supply _wp_http_referer and it will be preferred over the HTTP Referrer, so we need to add a hidden field to the form and fill it with the permalink of the post in question:

echo str_replace('</form>', '<input type="hidden" name="_wp_http_referer" value="' . esc_attr(get_permalink(123)) . '" /></form>', get_the_password_form(123));

with 123 being the post ID.