[Varnish] #261: regexp on cookie header breaks the URL

[Varnish]

#261: regexp on cookie header breaks the URL
----------------------+-----------------------------------------------------
 Reporter:  wichert   |       Owner:  phk                
     Type:  defect    |      Status:  new                
 Priority:  highest   |   Milestone:  Varnish 2.0 release
Component:  varnishd  |     Version:  trunk              
 Severity:  major     |    Keywords:                     
----------------------+-----------------------------------------------------
 Using varnish from trunk as of r2790.

 I have this bit of VCL:

 {{{
 sub vcl_recv {
     set req.backend = lb01;

     set req.url =
 "/VirtualHostBase/http/plone.customer.int:80/eli/VirtualHostRoot" req.url;

     if (req.request == "PURGE") {
         if (!client.ip ~ purge) {
             error 405 "Not allowed.";
         }
         lookup;
     }

     if (req.request == "POST") {
         pass;
     }

     if (req.http.If-None-Match) {
         pass;
     }

     if (req.url ~ "\.(gif|png|jpg|css|kss|js)") {
         remove req.http.cookie;
         lookup;
     }

     if (req.url ~ "VirtualHostRoot/?$" && ! req.http.cookie ~ "__ac" ) {
         if (req.http.cookie ~ "mainchain") {
                 set req.http.cookie = regsub(req.http.cookie,
 ".*mainchain=%22([^%22]*%22).*", "mainchain=\1");
         } else {
                 remove req.http.cookie;
         }
     }
 }
 }}}

 What this tries to do is sanitize the ''mainchain'' cookie when the user
 is looking at the frontpage. Strangely enough if a user tries to look at
 the frontpage varnish mangles the URL. Here is the relevant varnishlog:
 {{{
     9 ReqStart     c 10.121.10.84 41581 1274035111
     9 RxRequest    c GET
     9 RxURL        c /
     9 RxProtocol   c HTTP/1.1
     9 RxHeader     c Accept-Language: en
     9 RxHeader     c Accept-Encoding: gzip, deflate
     9 RxHeader     c Cookie: mainchain="89b21ac46cd08651c0fc0870a03470ec"
     9 RxHeader     c User-Agent: Mozilla/5.0 (Macintosh; U; Intel Mac OS X
 10_4_
 11; en) AppleWebKit/525.18 (KHTML, like Gecko) Version/3.1.1 Safari/525.18
     9 RxHeader     c Accept:
 text/xml,application/xml,application/xhtml+xml,text
 /html;q=0.9,text/plain;q=0.8,image/png,*/*;q=0.5
     9 RxHeader     c Cache-Control: max-age=0
     9 RxHeader     c Connection: keep-alive
     9 RxHeader     c Host: plone.customer.int
     9 VCL_call     c recv
     9 VCL_return   c pass
     9 VCL_call     c pass
     9 VCL_return   c pass
    11 TxRequest    b GET
    11 TxURL        b /VirtualHostBase/httcookie:
 mainchain=89b21ac46cd08651c0fc0
 870
    11 TxProtocol   b HTTP/1.1
    11 TxHeader     b Accept-Language: en
    11 TxHeader     b Accept-Encoding: gzip, deflate
    11 TxHeader     b User-Agent: Mozilla/5.0 (Macintosh; U; Intel Mac OS X
 10_4_
 11; en) AppleWebKit/525.18 (KHTML, like Gecko) Version/3.1.1 Safari/525.18
    11 TxHeader     b Accept:
 text/xml,application/xml,application/xhtml+xml,text
 /html;q=0.9,text/plain;q=0.8,image/png,*/*;q=0.5
    11 TxHeader     b Host: plone.customer.int
    11 TxHeader     b cookie: mainchain=89b21ac46cd08651c0fc0870a03470ec"
    11 TxHeader     b X-Varnish: 1274035111
    11 TxHeader     b X-Forwarded-For: 10.121.10.84
    11 RxProtocol   b HTTP/1.0
    11 RxStatus     b 400
    11 RxResponse   b Bad Request
    11 RxHeader     b Date: Tue, 24 Jun 2008 13:50:58 GMT
    11 RxHeader     b Content-Length: 136
    11 RxHeader     b Content-Type: text/html
    11 RxHeader     b Server: Medusa/24763
     9 ObjProtocol  c HTTP/1.0
     9 ObjStatus    c 400
     9 ObjResponse  c Bad Request
     9 ObjHeader    c Date: Tue, 24 Jun 2008 13:50:58 GMT
     9 ObjHeader    c Content-Type: text/html
     9 ObjHeader    c Server: Medusa/24763
 }}}

 Notice how the cookie is suddenly inserted in the middle of the URL.

-- 
Ticket URL: <http://varnish.projects.linpro.no/ticket/261>
Varnish <http://varnish.projects.linpro.no/>
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