La configuration des entĂȘtes du reverse proxy est incorrecte

Bonjour,

J’ai du rĂ©installer mon instance sur une nouvelle VM, tout en gardant une configuration trĂšs proche de l’ancienne. Et je n’arrive pas Ă  comprendre pourquoi j’ai ce message d’erreur qui s’affice :

La configuration des entĂȘtes du reverse proxy est incorrecte. C’est un problĂšme de sĂ©curitĂ©, qui peut permettre Ă  un attaquant d’usurper l’adresse IP affichĂ©e Ă  Nextcloud. Pour plus d’information, voir la documentation :arrow_upper_right:.

Voici ma config nginx sur mon reverse proxy (qui n’est pas sur la mĂȘme machine) :

server {
	server_name cloud.domain.com;

	listen 80;
	listen [::]:80;

	location ^~ /.well-known/acme-challenge {
		alias /var/www/html/cloud.domain.com/.well-know;		
		#proxy_pass http://cloud.domain.com/;
	}
	
	location / {
		return 301 https://$host$request_uri;
	}
}

server {
	server_name cloud.domain.com;

	listen 443 ssl http2;
	listen [::]:443 ssl http2;

	location / {
		
		proxy_set_header Host $host;
		proxy_set_header X-Real-IP $remote_addr;
        	proxy_set_header X-Forwarded-Proto $scheme;
		proxy_set_header X-Forwarded-Host $remote_addr;
		proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
		
		proxy_pass https://cloud.domain.com;

        	add_header Strict-Transport-Security "max-age=31536000; includeSubDomains; preload";
        	client_max_body_size 0;

        	
		access_log /var/log/nginx/nextcloud.access.log;
        	error_log /var/log/nginx/nextcloud.error.log;
	}

	location /.well-known/carddav {
		return 301 $scheme://$host/remote.php/dav;
	}

	location /.well-known/caldav {
		return 301 $scheme://$host/remote.php/dav;
	}

	ssl_certificate /etc/letsencrypt/live/cloud.domain.com/fullchain.pem; # managed by Certbot
	ssl_certificate_key /etc/letsencrypt/live/cloud.domain.com/privkey.pem; # managed by Certbot
	ssl_trusted_certificate /etc/letsencrypt/live/cloud.domain.com/chain.pem;
	
	include /etc/nginx/snippets/header.conf;
	include /etc/nginx/snippets/ssl.conf;

	access_log /var/log/nginx/cloud.domain.com.access.log;
	error_log /var/log/nginx/cloud.domain.com.error.log;

}

La config du nginx sur la VM de l’instance :

upstream php-handler {
    server unix:/run/php/php8.2-fpm.sock;
}

# Set the `immutable` cache control options only for assets with a cache busting `v` argument
map $arg_v $asset_immutable {
    "" "";
    default ", immutable";
}

server {
    listen 80;
    listen [::]:80;
    server_name cloud.domain.com;
    
    real_ip_header X-Forwarded-For;
    set_real_ip_from  10.0.0.0/8; 
    
    # Prevent nginx HTTP Server Detection
    server_tokens off;

    # Enforce HTTPS
    return 301 https://$server_name$request_uri;
}

server {
    listen 443      ssl http2;
    listen [::]:443 ssl http2;
    server_name cloud.domain.com;

    # Path to the root of your installation
    root /var/www/nextcloud;

    real_ip_header X-Forwarded-For;
    set_real_ip_from  10.0.0.0/8;

    # Use Mozilla's guidelines for SSL/TLS settings
    # https://mozilla.github.io/server-side-tls/ssl-config-generator/
    ssl_certificate     /etc/ssl/certs/cloud.domain.com/fullchain.pem;
    ssl_certificate_key /etc/ssl/private/cloud.domain.com/privkey.pem;

    # Prevent nginx HTTP Server Detection
    server_tokens off;

    # HSTS settings
    # WARNING: Only add the preload option once you read about
    # the consequences in https://hstspreload.org/. This option
    # will add the domain to a hardcoded list that is shipped
    # in all major browsers and getting removed from this list
    # could take several months.
    add_header Strict-Transport-Security "max-age=15768000; includeSubDomains; preload" always;

    # set max upload size and increase upload timeout:
    client_max_body_size 512M;
    client_body_timeout 300s;
    fastcgi_buffers 64 4K;

    # Enable gzip but do not remove ETag headers
    gzip on;
    gzip_vary on;
    gzip_comp_level 4;
    gzip_min_length 256;
    gzip_proxied expired no-cache no-store private no_last_modified no_etag auth;
    gzip_types application/atom+xml text/javascript application/javascript application/json application/ld+json application/manifest+json application/rss+xml application/vnd.geo+json application/vnd.ms-fontobject application/wasm application/x-font-ttf application/x-web-app-manifest+json application/xhtml+xml application/xml font/opentype image/bmp image/svg+xml image/x-icon text/cache-manifest text/css text/plain text/vcard text/vnd.rim.location.xloc text/vtt text/x-component text/x-cross-domain-policy;

    # Pagespeed is not supported by Nextcloud, so if your server is built
    # with the `ngx_pagespeed` module, uncomment this line to disable it.
    #pagespeed off;

    # The settings allows you to optimize the HTTP2 bandwidth.
    # See https://blog.cloudflare.com/delivering-http-2-upload-speed-improvements/
    # for tuning hints
    client_body_buffer_size 512k;

    # HTTP response headers borrowed from Nextcloud `.htaccess`
    add_header Referrer-Policy                   "no-referrer"       always;
    add_header X-Content-Type-Options            "nosniff"           always;
    add_header X-Frame-Options                   "SAMEORIGIN"        always;
    add_header X-Permitted-Cross-Domain-Policies "none"              always;
    add_header X-Robots-Tag                      "noindex, nofollow" always;
    add_header X-XSS-Protection                  "1; mode=block"     always;

    # Remove X-Powered-By, which is an information leak
    fastcgi_hide_header X-Powered-By;

    # Set .mjs and .wasm MIME types
    # Either include it in the default mime.types list
    # and include that list explicitly or add the file extension
    # only for Nextcloud like below:
    include mime.types;
    types {
        text/javascript mjs;
	application/wasm wasm;
    }

    # Specify how to handle directories -- specifying `/index.php$request_uri`
    # here as the fallback means that Nginx always exhibits the desired behaviour
    # when a client requests a path that corresponds to a directory that exists
    # on the server. In particular, if that directory contains an index.php file,
    # that file is correctly served; if it doesn't, then the request is passed to
    # the front-end controller. This consistent behaviour means that we don't need
    # to specify custom rules for certain paths (e.g. images and other assets,
    # `/updater`, `/ocs-provider`), and thus
    # `try_files $uri $uri/ /index.php$request_uri`
    # always provides the desired behaviour.
    index index.php index.html /index.php$request_uri;

    # Rule borrowed from `.htaccess` to handle Microsoft DAV clients
    location = / {
        if ( $http_user_agent ~ ^DavClnt ) {
            return 302 /remote.php/webdav/$is_args$args;
        }
    }

    location = /robots.txt {
        allow all;
        log_not_found off;
        access_log off;
    }

    # Make a regex exception for `/.well-known` so that clients can still
    # access it despite the existence of the regex rule
    # `location ~ /(\.|autotest|...)` which would otherwise handle requests
    # for `/.well-known`.
    location ^~ /.well-known {
        # The rules in this block are an adaptation of the rules
        # in `.htaccess` that concern `/.well-known`.

        location = /.well-known/carddav { return 301 /remote.php/dav/; }
        location = /.well-known/caldav  { return 301 /remote.php/dav/; }

        location /.well-known/acme-challenge    { try_files $uri $uri/ =404; }
        location /.well-known/pki-validation    { try_files $uri $uri/ =404; }

        # Let Nextcloud's API for `/.well-known` URIs handle all other
        # requests by passing them to the front-end controller.
        return 301 /index.php$request_uri;
    }

    # Rules borrowed from `.htaccess` to hide certain paths from clients
    location ~ ^/(?:build|tests|config|lib|3rdparty|templates|data)(?:$|/)  { return 404; }
    location ~ ^/(?:\.|autotest|occ|issue|indie|db_|console)                { return 404; }

    # Ensure this block, which passes PHP files to the PHP process, is above the blocks
    # which handle static assets (as seen below). If this block is not declared first,
    # then Nginx will encounter an infinite rewriting loop when it prepends `/index.php`
    # to the URI, resulting in a HTTP 500 error response.
    location ~ \.php(?:$|/) {
        # Required for legacy support
        rewrite ^/(?!index|remote|public|cron|core\/ajax\/update|status|ocs\/v[12]|updater\/.+|ocs-provider\/.+|.+\/richdocumentscode(_arm64)?\/proxy) /index.php$request_uri;

        fastcgi_split_path_info ^(.+?\.php)(/.*)$;
        set $path_info $fastcgi_path_info;

        try_files $fastcgi_script_name =404;

        include fastcgi_params;
        fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;
        fastcgi_param PATH_INFO $path_info;
        fastcgi_param HTTPS on;

        fastcgi_param modHeadersAvailable true;         # Avoid sending the security headers twice
        fastcgi_param front_controller_active true;     # Enable pretty urls
        fastcgi_pass php-handler;

        fastcgi_intercept_errors on;
        fastcgi_request_buffering off;

        fastcgi_max_temp_file_size 0;
    }

    # Serve static files
    location ~ \.(?:css|js|mjs|svg|gif|ico|jpg|png|webp|wasm|tflite|map|ogg|flac)$ {
        try_files $uri /index.php$request_uri;
        # HTTP response headers borrowed from Nextcloud `.htaccess`
        add_header Cache-Control                     "public, max-age=15778463$asset_immutable";
        add_header Referrer-Policy                   "no-referrer"       always;
        add_header X-Content-Type-Options            "nosniff"           always;
        add_header X-Frame-Options                   "SAMEORIGIN"        always;
        add_header X-Permitted-Cross-Domain-Policies "none"              always;
        add_header X-Robots-Tag                      "noindex, nofollow" always;
        add_header X-XSS-Protection                  "1; mode=block"     always;
        access_log off;     # Optional: Don't log access to assets
    }

    location ~ \.woff2?$ {
        try_files $uri /index.php$request_uri;
        expires 7d;         # Cache-Control policy borrowed from `.htaccess`
        access_log off;     # Optional: Don't log access to assets
    }

    # Rule borrowed from `.htaccess`
    location /remote {
        return 301 /remote.php$request_uri;
    }

    location / {
        try_files $uri $uri/ /index.php$request_uri;
    }
}

Et enfin mon fichier config.php :

<?php
$CONFIG = array (
  'instanceid' => 'xxxxxx',
  'passwordsalt' => 'xxxxx',
  'secret' => 'xxxxxxxxx',
  'trusted_domains' => 
  array (
    0 => 'cloud.domain.com',
    1 => 'rp.otherdomain.com',
    2 => '10.0.0.3',
  ),
  'overwritehost' => 'rp.otherdomain.com',
  'overwriteprotocol' => 'https',
  'overwritewebroot' => '',
  'overwritecondaddr' => '^10\\.0\\.0\\.3$',
  'overwrite.cli.url' => 'https://cloud.domain.com/',
  'datadirectory' => '/var/nc_datas',
  'dbtype' => 'mysql',
  'version' => '29.0.5.1',
  'dbname' => 'nextcloud_db',
  'dbhost' => 'localhost',
  'dbport' => '',
  'dbtableprefix' => 'oc_',
  'mysql.utf8mb4' => true,
  'dbuser' => 'nextcloud',
  'dbpassword' => 'xxxxxxx',
  'installed' => true,
  'maintenance_window_start' => 1,
  'filelocking.enabled' => 'true',
  'memcache.local' => '\\OC\\Memcache\\APCu',
  'memcache.distributed' => '\\OC\\Memcache\\Redis',
  'memcache.locking' => '\\OC\\Memcache\\Redis',
  'redis' => 
  array (
    'host' => 'localhost',
    'port' => 6379,
    'timeout' => 0.0,
    'password' => 'xxxxxxxxxx',
  ),
  'default_phone_region' => 'FR',
  'mail_smtpmode' => 'smtp',
  'mail_sendmailmode' => 'smtp',
  'mail_from_address' => 'admin',
  'mail_domain' => 'otherdomain.com',
  'mail_smtphost' => 'mail.otherdomain.com',
  'mail_smtpport' => '587',
  'mail_smtpauth' => 1,
  'mail_smtpname' => 'admin@otherdomain.com',
  'mail_smtppassword' => 'xxxxxxxxxxx',
  'log_type' => 'file',
  'loglevel' => 2,
  'logfile' => '/var/nc_datas/nextcloud.log',
  'log_rotate_size' => 1048576,
  'log_type_audit' => 'file',
  'logfile_audit' => '/var/nc_datas/audit.log',
  'maintenance' => false,
  'ldapProviderFactory' => 'OCA\\User_LDAP\\LDAPProviderFactory',
  'twofactor_enforced' => 'true',
  'twofactor_enforced_groups' => 
  array (
    0 => 'admin',
  ),
  'twofactor_enforced_excluded_groups' => 
  array (
  ),
  'theme' => '',
  'mail_smtpsecure' => 'ssl',
);

Auriez-vous une idĂ©e de ce qui peut poser problĂšme ? J’ai revu la doc et je pense avoir mis les bonnes variables.

Merci beaucoup

Personne n’a d’idĂ©e ? :slight_smile:

Bonjour, j’ai la mĂȘme difficultĂ© que vous et j’ai beau chercher et essayer plusieurs possibilitĂ© je n’arrive pas Ă  trouver. J’ai effectuer l’installation de nextcloud via une image NextcloudPi_RaspberryPi4_v1.55.1 sur mon Raspberry pi 4 et c’est la seul chose que je n’arrive pas Ă  solutionner.

L’erreur est la suivante :
La configuration des entĂȘtes du reverse proxy est incorrecte, ou vous accĂ©dez Ă  Nextcloud depuis un proxy de confiance. Si ce n’est pas le cas, c’est un problĂšme de sĂ©curitĂ©, qui peut permettre Ă  un attaquant d’usurper l’adresse IP affichĂ©e Ă  Nextcloud. Pour plus d’information, voir la documentation :arrow_upper_right:.

Le lien de la documentation est trĂšs utile mais ne corrige pas l’erreur de mon cĂŽtĂ©, voici mon fichier config.php :

<?php
$CONFIG = array (
  'default_phone_region' => 'FR',
  'passwordsalt' => '*****************************',
  'secret' => '*****************************************',
  'trusted_domains' =>
  array (
    0 => 'localhost',
    7 => 'nextcloudpi',
    5 => 'nextcloudpi.local',
    8 => 'nextcloudpi.lan',
    3 => 'mondomaine.ddns.net',
    11 => '****:****:****:****:****:****:****:****',
    1 => '***.***.*.**',
    14 => 'nextcloudpi',
    2 => 'mondomaine.ddns.net',
  ),
  'datadirectory' => '/media/USBdrive/ncdata/data',
  'dbtype' => 'mysql',
  'version' => '29.0.4.1',
  'overwrite.cli.url' => 'https://mondomaine.ddns.net/',
  'dbname' => 'nextcloud',
  'dbhost' => 'localhost',
  'dbport' => '',
  'dbtableprefix' => 'oc_',
  'mysql.utf8mb4' => true,
  'dbuser' => 'ncadmin',
  'dbpassword' => '************************************',
  'installed' => true,
  'instanceid' => '************',
  'memcache.local' => '\\OC\\Memcache\\Redis',
  'memcache.locking' => '\\OC\\Memcache\\Redis',
  'redis' =>
  array (
    'host' => '/var/run/redis/redis.sock',
    'port' => 0,
    'timeout' => 0.0,
    'password' => '**********************************',
  ),
  'tempdirectory' => '/media/USBdrive/ncdata/data/tmp',
  'mail_smtpmode' => 'sendmail',
  'mail_smtpauthtype' => 'LOGIN',
  'mail_from_address' => 'noreply',
  'mail_domain' => 'nextcloudpi.com',
  'preview_max_x' => '2048',
  'preview_max_y' => '2048',
  'jpeg_quality' => '60',
  'overwriteprotocol' => 'https',
  'maintenance' => false,
  'maintenance_window_start' => 1,
  'logfile' => '/media/USBdrive/ncdata/data/nextcloud.log',
  'trusted_proxies' =>
  array (
    11 => '***.*.*.*',
    12 => '::1',
    14 => '**.**.***.**',
    15 => '***.***.*.**',
  ),
  'loglevel' => '2',
  'log_type' => 'file',
  'htaccess.RewriteBase' => '/',
  'overwritewebroot' => '/',
  'overwritehost' => 'mondomaine.ddns.net',
  'overwritecondaddr' => '^192\\.168\\.1\\.12$',
);

Et j’ai bien regarder dans mon fichier apache2/sites-enabled/001-nextcloud.conf mais il ne conseille pas de le modifier :

### DO NOT EDIT! THIS FILE HAS BEEN AUTOMATICALLY GENERATED. CHANGES WILL BE OVERWRITTEN ###

Donc je me suis rabattue sur l’accùs " nano /etc/apache2/sites-enabled/000-default.conf " qui me paraüt correct :

<VirtualHost _default_:80>
  DocumentRoot /var/www/nextcloud
  <IfModule mod_rewrite.c>
    RewriteEngine On
    RewriteRule ^.well-known/acme-challenge/ - [L]
    RewriteCond %{HTTPS} !=on
    RewriteRule ^/?(.*) https://%{SERVER_NAME}/$1 [R,L]
  </IfModule>
  <Directory /var/www/nextcloud/>
    Options +FollowSymlinks
    AllowOverride All
    <IfModule mod_dav.c>
      Dav off
    </IfModule>
    LimitRequestBody 0
  </Directory>
</VirtualHost>

Il ne me reste donc plus que " nano /etc/apache2/sites-enabled/ncp.conf " :

Listen 4443
<VirtualHost _default_:4443>
  DocumentRoot /var/www/ncp-web
  SSLEngine on
  SSLCertificateFile /etc/letsencrypt/live/mondomaine.ddns.net/fullchain.pem
  SSLCertificateKeyFile /etc/letsencrypt/live/mondomaine.ddns.net/privkey.pem
  <IfModule mod_headers.c>
    Header always set Strict-Transport-Security "max-age=15768000; includeSubDomains"
  </IfModule>

  # 2 days to avoid very big backups requests to timeout
  TimeOut 172800

  <IfModule mod_authnz_external.c>
    DefineExternalAuth pwauth pipe /usr/sbin/pwauth
  </IfModule>

</VirtualHost>
<Directory /var/www/ncp-web/>

  AuthType Basic
  AuthName "ncp-web login"
  AuthBasicProvider external
  AuthExternal pwauth

  <RequireAll>

   <RequireAny>
      Require host localhost
      Require local
      Require ip ***.*** #Il n'y a que les 6 premiers chiffres de mon IP
      Require ip 172
      Require ip 10
      Require ip fe80::/10
      Require ip fd00::/8
   </RequireAny>

   Require user ncp

  </RequireAll>

</Directory>

Est ce qu’un Ăąme de passage :innocent: par ici Ă  eu le mĂȘme cas afin de partager une solution Ă  ceci ?
Et par ailleurs m’expliquer ce qui manquait temps à ma config :man_teacher: !

Vous remerciant par avance noble communauté
Votre serviteur :slight_smile:

Je viens de remarquer cela dans la documentation pour Apache2

RewriteEngine On
RewriteRule ^/.well-known/carddav https://%{SERVER_NAME}/remote.php/dav/ [R=301,L]
RewriteRule ^/.well-known/caldav https://%{SERVER_NAME}/remote.php/dav/ [R=301,L]

Je vais regarder demain mais me pose la question sur quelle fichier conf dois je ajouter ces lignes ?
Et est ce ” SERVER_NAME ” correspond au nom de domaine ?

Modification en cherchant un peu plus la documentation explique bien de " DĂ©finissez le trusted_proxies paramĂštre comme un tableau de :
** Adresses IPv4*
** Plages IPv4 en notation CIDR*
** Adresses IPv6*
** Plages IPv6 en notation CIDR*

Donc je vérifie mes Ip en allant sur le nextcloudpi :

Et je les ajoutes avec un ligne en plus avec la notation CIDR.
Prenons l’exemple :
IPv4 : 44.55.123.66
Ipv4 CIDR : 44.55.123.66/32
IPv6 : 8f04:5hy6:7ty8:4q56:9p63:4e87:4fd3:7r8t
IPv6 CIDR : 8f04:5hy6:7ty8:4q56:9p63:4e87:4fd3:7r8t/102

Donc si je comprend bien mon fichier config.php doit avoir la section trusted_proxies comme ceci ?

0=> ‘44.55.123.66’
1=> ‘44.55.123.66/32’
2=> ‘8f04:5hy6:7ty8:4q56:9p63:4e87:4fd3:7r8t’
3=> ‘8f04:5hy6:7ty8:4q56:9p63:4e87:4fd3:7r8t/102’

Je sauvegarde et fait un restart apache2 et php8.3-fpm, je recharge la page d’avertissement et l’erreur ne disparait pas.

Je supprime la 1ùre ligne " 0=> ‘44.55.123.66’" sauvegarde et relance les services. Et là pouf l’erreur à disparu ! C’est merveilleux me diriez vous !

Mais non en effectuant un sudo reboot, le message rĂ©apparait car oui les anciennes lignes sont rĂ©apparu je n’arrive Ă  les faire retirĂ©s, auriez vous une idĂ©e ?

Il y a un fichier d’exemples dans le rĂ©pertoire “config”, Ă  cĂŽtĂ© du fichier “config.php”. C’est “config.sample.php”. L’exemple vous montre la syntaxe pour le paramĂštre trusted_proxies. ‘trusted_proxies’ => [‘203.0.113.45’, ‘198.51.100.128’, ‘192.168.2.0/24’], . Il ne s’agit pas d’indiquer toutes les sortes d’IP mais d’en choisir une. Et si vous avez plusieurs adresses IP pour votre proxy, de les indiquer. (Vous indiquez les proxys auxquels vous faites confiance, puisque ce sont eux qui redirigent les requĂȘtes de votre installation vers vos clients).