如何修复HTTPS Wordpress wp-admin重定向循环

Question

I know there is a lot of questions like this but none has given me an answer that resolved my problem with my WordPress wp-admin/ page, the browser throws an ERR_TOO_MANY_REDIRECTS error, I have disabled all plugins, cleared my cache and cookies, edited my wp-config.php file but still nothing.

my apache config:

<VirtualHost *:80>
    ServerName example.com
    ServerAlias www.example.com
    Redirect permanent / "https://example.com/"

    ErrorLog ${APACHE_LOG_DIR}/error.log
    CustomLog ${APACHE_LOG_DIR}/access.log combined
</VirtualHost>

<IfModule mod_ssl.c>
    <VirtualHost *:443>

        ServerName example.com
        ServerAlias www.example.com

        DocumentRoot /var/www

        Include /etc/letsencrypt/options-ssl-apache.conf
        SSLCertificateFile /etc/letsencrypt/live/example.com/fullchain.pem
        SSLCertificateKeyFile /etc/letsencrypt/live/example.com/privkey.pem

        ErrorLog ${APACHE_LOG_DIR}/error.log
        CustomLog ${APACHE_LOG_DIR}/access.log combined

        <Directory /var/www>
            AllowOverride None
            Order Allow,Deny
            Allow from All

            DirectoryIndex index.php

            <IfModule mod_rewrite.c>
                RewriteEngine On
                RewriteCond %{REQUEST_URI}::$1 ^(/.+)/(.*)::\2$
                RewriteRule ^(.*) - [E=BASE:%1]
                RewriteCond %{HTTP:Authorization} .
                RewriteRule ^ - [E=HTTP_AUTHORIZATION:%{HTTP:Authorization}]

                RewriteCond %{ENV:REDIRECT_STATUS} ^$
                RewriteRule ^index\.php(?:/(.*)|$) %{ENV:BASE}/$1 [R=301,L]

                RewriteCond %{REQUEST_FILENAME} -f
                RewriteRule ^ - [L]

                RewriteRule ^ %{ENV:BASE}/index.php [L]
            </IfModule>

            <IfModule !mod_rewrite.c>
                <IfModule mod_alias.c>
                    RedirectMatch 307 ^/$ /index.php
                </IfModule>
            </IfModule>

        </Directory>

    </VirtualHost>
</IfModule>

my wp-config.php

define('WP_HOME','https://example.com');
define('WP_SITEURL','https://example.com');

/** SSL */
define('FORCE_SSL_ADMIN', true);

if((empty($_SERVER['HTTPS']) || $_SERVER['HTTPS'] == 'off') && $_SERVER['HTTP_X_FORWARDED_PROTO'] == 'https')
  $_SERVER['HTTPS'] = 'on';

my $_SERVER variable:

Array
(
    [SERVER_SOFTWARE] => Apache/2.4.29 (Ubuntu)
    [REQUEST_URI] => /wp-admin/?test=1
    [REDIRECT_HTTPS] => on
    [REDIRECT_SSL_TLS_SNI] => example.com
    [REDIRECT_STATUS] => 200
    [HTTPS] => on
    [SSL_TLS_SNI] => example.com
    [HTTP_HOST] => example.com
    [HTTP_CONNECTION] => keep-alive
    [HTTP_UPGRADE_INSECURE_REQUESTS] => 1
    [HTTP_USER_AGENT] => Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/72.0.3626.109 Safari/537.36
    [HTTP_DNT] => 1
    [HTTP_ACCEPT] => text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,image/apng,*/*;q=0.8
    [HTTP_ACCEPT_ENCODING] => gzip, deflate, br
    [HTTP_ACCEPT_LANGUAGE] => es-ES,es;q=0.9,en;q=0.8,pt;q=0.7
    [HTTP_COOKIE] => PHPSESSID=84c3jbfdtbmcl4jnibgobm3666
    [PATH] => /usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin
    [SERVER_SIGNATURE] => 
Apache/2.4.29 (Ubuntu) Server at example.com Port 443


    [SERVER_NAME] => example.com
    [SERVER_ADDR] => xxx.xxx.xxx.xxx
    [SERVER_PORT] => 443
    [REMOTE_ADDR] => xxx.xxx.xxx.xxx
    [DOCUMENT_ROOT] => /var/www
    [REQUEST_SCHEME] => https
    [CONTEXT_PREFIX] => 
    [CONTEXT_DOCUMENT_ROOT] => /var/www
    [SERVER_ADMIN] => [no address given]
    [SCRIPT_FILENAME] => /var/www/index.php
    [REMOTE_PORT] => 52242
    [REDIRECT_URL] => /wp-admin/
    [REDIRECT_QUERY_STRING] => test=1
    [GATEWAY_INTERFACE] => CGI/1.1
    [SERVER_PROTOCOL] => HTTP/1.1
    [REQUEST_METHOD] => GET
    [QUERY_STRING] => test=1
    [SCRIPT_NAME] => /index.php
    [PHP_SELF] => /index.php
    [REQUEST_TIME_FLOAT] => 1550424580.519
    [REQUEST_TIME] => 1550424580
)

Answer 1

In some setups HTTP_X_FORWARDED_PROTO contains a comma seperated list. (ex http,https )

This seems to be the case in your setup. Checking that HTTP_X_FORWARDED_PROTO contains the string https instead of checking that it equals https should do the trick.

Try the following:

if (strpos($_SERVER['HTTP_X_FORWARDED_PROTO'], 'https') !== false)
    $_SERVER['HTTPS']='on';

Side note: You can safely ignore this part of your check: (empty($_SERVER['HTTPS']) || $_SERVER['HTTPS'] == 'off')