Le caractère générique Cors Access-Control-Allow-Headers est-il ignoré?

Question

Je ne parviens pas à faire fonctionner correctement une requête cors interdomaine à l'aide de chrome. 

En-têtes de demande:

Accept:*/*
Accept-Charset:ISO-8859-1,utf-8;q=0.7,*;q=0.3
Accept-Encoding:gzip,deflate,sdch
Accept-Language:en-US,en;q=0.8
Access-Control-Request-Headers:Origin, content-type
Access-Control-Request-Method:POST
Connection:keep-alive
User-Agent:Mozilla/5.0 (Macintosh; Intel Mac OS X 10_8_2) AppleWebKit/537.4 (KHTML, like Gecko) Chrome/22.0.1229.94 Safari/537.4

En-têtes de réponse:

Access-Control-Allow-Headers:*
Access-Control-Allow-Origin:*
Allow:GET, POST, OPTIONS
Content-Length:0
Date:Tue, 30 Oct 2012 20:04:28 GMT
Server:BaseHTTP/0.3 Python/2.7.3

Erreur:

XMLHttpRequest cannot load domain. Request header field Content-Type is not allowed by Access-Control-Allow-Headers.

Et le code python servant la requête d’options est:

self.send_response(200)
self.send_header('Allow', 'GET, POST, OPTIONS')
self.send_header('Access-Control-Allow-Origin', '*')
self.send_header('Access-Control-Allow-Headers', '*')
self.send_header('Content-Length', '0')
self.end_headers()

Il semble que le caractère générique Access-Control-Allow-Origin soit ignoré?

Answer 1

La prise en charge des caractères génériques dans l'en-tête Access-Control-Allow-Headers était a été ajoutée au niveau de vie seulement en mai 2016. Il est donc possible qu'elle ne soit pas prise en charge par tous les navigateurs. Sur les navigateurs qui ne l'utilisent pas encore, il doit correspondre exactement: https://www.w3.org/TR/2014/REC-cors-20140116/#access-control-allow-headers-response- entête

Si vous attendez un grand nombre d'en-têtes, vous pouvez lire la valeur de l'en-tête Access-Control-Request-Headers et renvoyer cette valeur dans l'en-tête Access-Control-Allow-Headers.

Answer 2

Ces en-têtes CORS ne prennent pas en charge la valeur *, le seul moyen est de remplacer * par ceci:

Accept, Accept-CH, Accept-Charset, Accept-Datetime, Accept-Encoding, Accept-Ext, Accept-Features, Accept-Language, Accept-Params, Accept-Ranges, Access-Control-Allow-Credentials, Access-Control-Allow-Headers, Access-Control-Allow-Methods, Access-Control-Allow-Origin, Access-Control-Expose-Headers, Access-Control-Max-Age, Access-Control-Request-Headers, Access-Control-Request-Method, Age, Allow, Alternates, Authentication-Info, Authorization, C-Ext, C-Man, C-Opt, C-PEP, C-PEP-Info, CONNECT, Cache-Control, Compliance, Connection, Content-Base, Content-Disposition, Content-Encoding, Content-ID, Content-Language, Content-Length, Content-Location, Content-MD5, Content-Range, Content-Script-Type, Content-Security-Policy, Content-Style-Type, Content-Transfer-Encoding, Content-Type, Content-Version, Cookie, Cost, DAV, DELETE, DNT, DPR, Date, Default-Style, Delta-Base, Depth, Derived-From, Destination, Differential-ID, Digest, ETag, Expect, Expires, Ext, From, GET, GetProfile, HEAD, HTTP-date, Host, IM, If, If-Match, If-Modified-Since, If-None-Match, If-Range, If-Unmodified-Since, Keep-Alive, Label, Last-Event-ID, Last-Modified, Link, Location, Lock-Token, MIME-Version, Man, Max-Forwards, Media-Range, Message-ID, Meter, Negotiate, Non-Compliance, OPTION, OPTIONS, OWS, Opt, Optional, Ordering-Type, Origin, Overwrite, P3P, PEP, PICS-Label, POST, PUT, Pep-Info, Permanent, Position, Pragma, ProfileObject, Protocol, Protocol-Query, Protocol-Request, Proxy-Authenticate, Proxy-Authentication-Info, Proxy-Authorization, Proxy-Features, Proxy-Instruction, Public, RWS, Range, Referer, Refresh, Resolution-Hint, Resolver-Location, Retry-After, Safe, Sec-Websocket-Extensions, Sec-Websocket-Key, Sec-Websocket-Origin, Sec-Websocket-Protocol, Sec-Websocket-Version, Security-Scheme, Server, Set-Cookie, Set-Cookie2, SetProfile, SoapAction, Status, Status-URI, Strict-Transport-Security, SubOK, Subst, Surrogate-Capability, Surrogate-Control, TCN, TE, TRACE, Timeout, Title, Trailer, Transfer-Encoding, UA-Color, UA-Media, UA-Pixels, UA-Resolution, UA-Windowpixels, URI, Upgrade, User-Agent, Variant-Vary, Vary, Version, Via, Viewport-Width, WWW-Authenticate, Want-Digest, Warning, Width, X-Content-Duration, X-Content-Security-Policy, X-Content-Type-Options, X-CustomHeader, X-DNSPrefetch-Control, X-Forwarded-For, X-Forwarded-Port, X-Forwarded-Proto, X-Frame-Options, X-Modified, X-OTHER, X-PING, X-PINGOTHER, X-Powered-By, X-Requested-With

---

.htaccess Exemple (CORS inclus):

<IfModule mod_headers.c>
  Header unset Connection
  Header unset Time-Zone
  Header unset Keep-Alive
  Header unset Access-Control-Allow-Origin
  Header unset Access-Control-Allow-Headers
  Header unset Access-Control-Expose-Headers
  Header unset Access-Control-Allow-Methods
  Header unset Access-Control-Allow-Credentials

  Header set   Connection                         keep-alive
  Header set   Time-Zone                          "Asia/Jerusalem"
  Header set   Keep-Alive                         timeout=100,max=500
  Header set   Access-Control-Allow-Origin        "*"
  Header set   Access-Control-Allow-Headers       "Accept, Accept-CH, Accept-Charset, Accept-Datetime, Accept-Encoding, Accept-Ext, Accept-Features, Accept-Language, Accept-Params, Accept-Ranges, Access-Control-Allow-Credentials, Access-Control-Allow-Headers, Access-Control-Allow-Methods, Access-Control-Allow-Origin, Access-Control-Expose-Headers, Access-Control-Max-Age, Access-Control-Request-Headers, Access-Control-Request-Method, Age, Allow, Alternates, Authentication-Info, Authorization, C-Ext, C-Man, C-Opt, C-PEP, C-PEP-Info, CONNECT, Cache-Control, Compliance, Connection, Content-Base, Content-Disposition, Content-Encoding, Content-ID, Content-Language, Content-Length, Content-Location, Content-MD5, Content-Range, Content-Script-Type, Content-Security-Policy, Content-Style-Type, Content-Transfer-Encoding, Content-Type, Content-Version, Cookie, Cost, DAV, DELETE, DNT, DPR, Date, Default-Style, Delta-Base, Depth, Derived-From, Destination, Differential-ID, Digest, ETag, Expect, Expires, Ext, From, GET, GetProfile, HEAD, HTTP-date, Host, IM, If, If-Match, If-Modified-Since, If-None-Match, If-Range, If-Unmodified-Since, Keep-Alive, Label, Last-Event-ID, Last-Modified, Link, Location, Lock-Token, MIME-Version, Man, Max-Forwards, Media-Range, Message-ID, Meter, Negotiate, Non-Compliance, OPTION, OPTIONS, OWS, Opt, Optional, Ordering-Type, Origin, Overwrite, P3P, PEP, PICS-Label, POST, PUT, Pep-Info, Permanent, Position, Pragma, ProfileObject, Protocol, Protocol-Query, Protocol-Request, Proxy-Authenticate, Proxy-Authentication-Info, Proxy-Authorization, Proxy-Features, Proxy-Instruction, Public, RWS, Range, Referer, Refresh, Resolution-Hint, Resolver-Location, Retry-After, Safe, Sec-Websocket-Extensions, Sec-Websocket-Key, Sec-Websocket-Origin, Sec-Websocket-Protocol, Sec-Websocket-Version, Security-Scheme, Server, Set-Cookie, Set-Cookie2, SetProfile, SoapAction, Status, Status-URI, Strict-Transport-Security, SubOK, Subst, Surrogate-Capability, Surrogate-Control, TCN, TE, TRACE, Timeout, Title, Trailer, Transfer-Encoding, UA-Color, UA-Media, UA-Pixels, UA-Resolution, UA-Windowpixels, URI, Upgrade, User-Agent, Variant-Vary, Vary, Version, Via, Viewport-Width, WWW-Authenticate, Want-Digest, Warning, Width, X-Content-Duration, X-Content-Security-Policy, X-Content-Type-Options, X-CustomHeader, X-DNSPrefetch-Control, X-Forwarded-For, X-Forwarded-Port, X-Forwarded-Proto, X-Frame-Options, X-Modified, X-OTHER, X-PING, X-PINGOTHER, X-Powered-By, X-Requested-With"
  Header set   Access-Control-Expose-Headers      "Accept, Accept-CH, Accept-Charset, Accept-Datetime, Accept-Encoding, Accept-Ext, Accept-Features, Accept-Language, Accept-Params, Accept-Ranges, Access-Control-Allow-Credentials, Access-Control-Allow-Headers, Access-Control-Allow-Methods, Access-Control-Allow-Origin, Access-Control-Expose-Headers, Access-Control-Max-Age, Access-Control-Request-Headers, Access-Control-Request-Method, Age, Allow, Alternates, Authentication-Info, Authorization, C-Ext, C-Man, C-Opt, C-PEP, C-PEP-Info, CONNECT, Cache-Control, Compliance, Connection, Content-Base, Content-Disposition, Content-Encoding, Content-ID, Content-Language, Content-Length, Content-Location, Content-MD5, Content-Range, Content-Script-Type, Content-Security-Policy, Content-Style-Type, Content-Transfer-Encoding, Content-Type, Content-Version, Cookie, Cost, DAV, DELETE, DNT, DPR, Date, Default-Style, Delta-Base, Depth, Derived-From, Destination, Differential-ID, Digest, ETag, Expect, Expires, Ext, From, GET, GetProfile, HEAD, HTTP-date, Host, IM, If, If-Match, If-Modified-Since, If-None-Match, If-Range, If-Unmodified-Since, Keep-Alive, Label, Last-Event-ID, Last-Modified, Link, Location, Lock-Token, MIME-Version, Man, Max-Forwards, Media-Range, Message-ID, Meter, Negotiate, Non-Compliance, OPTION, OPTIONS, OWS, Opt, Optional, Ordering-Type, Origin, Overwrite, P3P, PEP, PICS-Label, POST, PUT, Pep-Info, Permanent, Position, Pragma, ProfileObject, Protocol, Protocol-Query, Protocol-Request, Proxy-Authenticate, Proxy-Authentication-Info, Proxy-Authorization, Proxy-Features, Proxy-Instruction, Public, RWS, Range, Referer, Refresh, Resolution-Hint, Resolver-Location, Retry-After, Safe, Sec-Websocket-Extensions, Sec-Websocket-Key, Sec-Websocket-Origin, Sec-Websocket-Protocol, Sec-Websocket-Version, Security-Scheme, Server, Set-Cookie, Set-Cookie2, SetProfile, SoapAction, Status, Status-URI, Strict-Transport-Security, SubOK, Subst, Surrogate-Capability, Surrogate-Control, TCN, TE, TRACE, Timeout, Title, Trailer, Transfer-Encoding, UA-Color, UA-Media, UA-Pixels, UA-Resolution, UA-Windowpixels, URI, Upgrade, User-Agent, Variant-Vary, Vary, Version, Via, Viewport-Width, WWW-Authenticate, Want-Digest, Warning, Width, X-Content-Duration, X-Content-Security-Policy, X-Content-Type-Options, X-CustomHeader, X-DNSPrefetch-Control, X-Forwarded-For, X-Forwarded-Port, X-Forwarded-Proto, X-Frame-Options, X-Modified, X-OTHER, X-PING, X-PINGOTHER, X-Powered-By, X-Requested-With"
  Header set   Access-Control-Allow-Methods       "CONNECT, DEBUG, DELETE, DONE, GET, HEAD, HTTP, HTTP/0.9, HTTP/1.0, HTTP/1.1, HTTP/2, OPTIONS, Origin, ORIGINS, PATCH, POST, PUT, QUIC, REST, SESSION, SHOULD, SPDY, TRACE, TRACK"
  Header set   Access-Control-Allow-Credentials   "true"

  Header set DNT "0"
  Header set Accept-Ranges "bytes"
  Header set Vary "Accept-Encoding"
  Header set X-UA-Compatible "IE=Edge,chrome=1"
  Header set X-Frame-Options "SAMEORIGIN"
  Header set X-Content-Type-Options "nosniff"
  Header set X-Xss-Protection "1; mode=block"
</IfModule>

---

FAQ:

• Pourquoi les valeurs Access-Control-Allow-Headers, Access-Control-Expose-Headers, Access-Control-Allow-Methods sont-elles super longues?

  Celles-ci ne supportent pas la syntaxe *, j'ai donc rassemblé les en-têtes les plus courants (et les plus exotiques) sur le Web, dans différents formats # 1# 2# 3 _{(et je mettrai à jour la liste de temps en temps)}

• Pourquoi utilisez-vous la syntaxe Header unset ______?

  Les serveurs GoDaddy (sur lesquels mon site Web est hébergé ..) ont un bogue étrange dans lequel, si les en-têtes sont déjà définis, la valeur précédente rejoindra celle existante .. (au lieu de la remplacer) de cette façon, je "nettoie" les valeurs existantes. _{(vraiment juste une solution rapide & & sale)}

• Est-ce que je peux utiliser «tel quel»?

  Eh bien .. la plupart du temps, la réponse serait OUI, car le .htaccess limite les en-têtes aux scripts (PHP, HTML, ...) et aux ressources (.JPG, .JS, .CSS) servis à partir des éléments suivants "dossier" -location. Vous voudrez peut-être éventuellement supprimer les lignes Access-Control-Allow-Methods. _{De plus, Connection, Time-Zone, Keep-Alive et DNT, Accept-Ranges, Vary, X-UA-Compatible, X-Frame-Options, X-Content-Type-Options et X-Xss-Protection sont juste une suggestion que j'utilise pour mon service en ligne .. n'hésitez pas à les supprimer aussi ...}

_{tiré de mon commentaire ci-dessus}

Answer 3

J'ai trouvé que Access-Control-Allow-Headers: * devrait être défini UNIQUEMENT pour la demande "OPTIONS" . Si vous le renvoyez pour une demande POST, le navigateur annule la demande (au moins pour chrome)

Le code PHP suivant fonctionne pour moi 

// Allow CORS
if (isset($_SERVER['HTTP_Origin'])) {
    header("Access-Control-Allow-Origin: {$_SERVER['HTTP_Origin']}");
    header('Access-Control-Allow-Credentials: true');    
    header("Access-Control-Allow-Methods: GET, POST, OPTIONS"); 
}   
// Access-Control headers are received during OPTIONS requests
if ($_SERVER['REQUEST_METHOD'] == 'OPTIONS') {
    header("Access-Control-Allow-Headers: *");
}

J'ai trouvé des questions similaires avec une réponse trompeuse:

• Le fil du serveur dit qu'il s'agit d'un bogue chrome datant de 2 ans: Access-Control-Allow-Headers ne correspond pas à localhost. C'est faux: je peux utiliser CORS sur mon serveur local avec Post normalement
• Access-Control-Allow-Headers accepte les caractères génériques. C'est également faux, le joker fonctionne pour moi (j'ai testé uniquement avec Chrome)

Cela me prend une demi-journée pour comprendre le problème.

Bonne codage

Answer 4

Cité de monsur,

L'en-tête Access-Control-Allow-Headers n'autorise pas les caractères génériques. Il doit être une correspondance exacte: http://www.w3.org/TR/cors/#access-control-allow-headers-response-header .

Alors voici ma solution php.

if ($_SERVER['REQUEST_METHOD'] == 'OPTIONS') {
  $headers=getallheaders();
  @$ACRH=$headers["Access-Control-Request-Headers"];
  header("Access-Control-Allow-Headers: $ACRH");
}

Answer 5

voici l'incantation pour nginx, à l'intérieur d'un 

location / {
    # Simple requests
    if ($request_method ~* "(GET|POST)") {
      add_header "Access-Control-Allow-Origin"  *;
    }

    # Preflighted requests
    if ($request_method = OPTIONS ) {
      add_header "Access-Control-Allow-Origin"  *;
      add_header "Access-Control-Allow-Methods" "GET, POST, OPTIONS, HEAD";
      add_header "Access-Control-Allow-Headers" "Authorization, Origin, X-Requested-With, Content-Type, Accept";
    }

}