code/modules/httpobserver.js

   1 /* coded by Ketmar // Invisible Vector (psyc://ketmar.no-ip.org/~Ketmar)
   2  * Understanding is not required. Only obedience.
   3  *
   4  * This program is free software. It comes without any warranty, to
   5  * the extent permitted by applicable law. You can redistribute it
   6  * and/or modify it under the terms of the Do What The Fuck You Want
   7  * To Public License, Version 2, as published by Sam Hocevar. See
   8  * http://www.wtfpl.net/txt/copying/ for more details.
   9  */
  10 // http observer
  11 var EXPORTED_SYMBOLS = [
  12 ];
  13
  14 let {utils:Cu, classes:Cc, interfaces:Ci, results:Cr} = Components;
  15
  16
  17 //////////////////////////////////////////////////////////////////////////////
  18 Cu.import("resource://gre/modules/Services.jsm");
  19
  20 //////////////////////////////////////////////////////////////////////////////
  21 Cu.import("chrome://k8-imago-code/content/modules/utils.js");
  22 Cu.import(MODULE_PATH+"debuglog.js");
  23 Cu.import(MODULE_PATH+"prefs.js");
  24 Cu.import(MODULE_PATH+"tamper.js");
  25 Cu.import(MODULE_PATH+"stoplist.js");
  26 Cu.import(MODULE_PATH+"imgreload.js");
  27 Cu.import(MODULE_PATH+"hazard.js");
  28 Cu.import(MODULE_PATH+"rule-engine.js");
  29
  30
  31 //////////////////////////////////////////////////////////////////////////////
  32 // init some functions from window
  33 let btoa = null;
  34
  35 registerWindowHook("load", function (win) {
  36   btoa = win.btoa;
  37 });
  38
  39 registerWindowHook("unload", function (win) {
  40   btoa = null;
  41 });
  42
  43
  44 //////////////////////////////////////////////////////////////////////////////
  45 let tldsvc = Cc["@mozilla.org/network/effective-tld-service;1"].getService(Ci.nsIEffectiveTLDService);
  46
  47
  48 //////////////////////////////////////////////////////////////////////////////
  49 let imagectRE = /^image\//;
  50
  51
  52 let httpRequestObserver = {
  53   QueryInterface: function (aIID) {
  54     if (aIID.equals(Ci.nsIObserver) || aIID.equals(Ci.nsISupports)) return this;
  55     throw Components.results.NS_NOINTERFACE;
  56   },
  57
  58   observe: function (aSubject, aTopic, aData) {
  59     if (!(aSubject instanceof Ci.nsIHttpChannel)) return;
  60
  61     if (aTopic === "http-on-examine-response") {
  62       // aSubject is request object
  63       let httpChannel = aSubject.QueryInterface(Ci.nsIHttpChannel);
  64
  65       let dw = getDomWindowForChannel(httpChannel), bro = null;
  66       if (dw) {
  67         bro = getBrowserForDomWindow(dw);
  68         if (bro) {
  69           if (PREFS.debugLog) conlog("[", httpChannel.URI.spec, "] browser: ", bro.currentURI.spec);
  70         } else {
  71           if (PREFS.debugLog) conlog("*** [", httpChannel.URI.spec, "] NO browser");
  72           return;
  73         }
  74       } else {
  75         if (PREFS.debugLog) conlog("*** [", httpChannel.URI.spec, "] NO dom window");
  76         return;
  77       }
  78       let docURI = bro.currentURI.spec;
  79
  80       // process redirects for whitelisted and blacklisted images
  81       if (httpChannel.responseStatus >= 300 && httpChannel.responseStatus <= 399) {
  82         let wl = isUnblockedImage(httpChannel.URI, docURI);
  83         let bl = isBlockedImage(httpChannel.URI, docURI);
  84         if (wl || bl) {
  85           imageLoaderActivated(httpChannel.URI, docURI);
  86           if (PREFS.debugLog) conlog("***GOT IMAGE REDIRECT FOR ["+httpChannel.URI.spec+"]! responseStatus="+httpChannel.responseStatus);
  87           let loc = httpChannel.getResponseHeader("Location");
  88           if (loc) {
  89             if (PREFS.debugLog) conlog("***REDIRECT TO: ["+loc+"]");
  90             if (wl) {
  91               unblockImage(loc, docURI);
  92               registerManualReloadRedirectURL(httpChannel.URI.spec, loc);
  93             } else {
  94               blockImage(loc, docURI);
  95             }
  96           }
  97         }
  98       }
  99
 100       let ctype = httpChannel.contentType;
 101       if (!ctype) return;
 102       if (!imagectRE.test(ctype) /*&& ctype !== "application/octet-stream"*/) {
 103         // if we got a non-redirecting reply, reset image status
 104         resetImageStatus(httpChannel.URI, docURI);
 105         //conlog("ctype: ", ctype);
 106         return;
 107       }
 108
 109       // intercept and count
 110       if (Math.floor(httpChannel.responseStatus/100) === 2) {
 111         imageLoaderActivated(httpChannel.URI, docURI);
 112         let doSizeBlockInTamper = false;
 113
 114         if (PREFS.debugLog) conlog("*** CHECKING [", httpChannel.URI.spec, "]...");
 115         let isoctet = false/*ctype === "application/octet-stream"*/;
 116         // whitelisted?
 117         if (isUnblockedImage(httpChannel.URI, docURI)) {
 118           if (PREFS.debugLog) conlog("*** UNBLOCKED [", httpChannel.URI.spec, "]...");
 119           return;
 120         }
 121         // blacklisted?
 122         let blacklisted = (isBlockedImage(httpChannel.URI, docURI));
 123         // global black/white lists
 124         if (!blacklisted) {
 125           //TODO: list priorities
 126           // this can pappen for "chrome:", for exampe
 127           let host = (httpChannel.URI.host ? httpChannel.URI.host : "nohost");
 128           if (WHITE_HOSTS[host]) {
 129             // whitelisted
 130             if (PREFS.debugLog) conlog("*** WHITE HOST [", httpChannel.URI.spec, "]...");
 131             return;
 132           }
 133           if (host in BLACK_HOSTS) blacklisted = BLACK_HOSTS[host];
 134         }
 135         if (!blacklisted && dw && PREFS.maxTotalBytesForDoc > 0) {
 136           try {
 137             let ctlen = parseInt(httpChannel.getResponseHeader("Content-Length"), 10);
 138             if (isNaN(ctlen)) doSizeBlockInTamper = true;
 139             if (!isNaN(ctlen) && ctlen > 0) {
 140               let isize = getByteCounterForDomWindow(dw)+ctlen;
 141               if (isize >= PREFS.maxTotalBytesForDoc) {
 142                 if (PREFS.debugLog) conlog("*** [", httpChannel.URI.spec, "]: blacklisted due to bytes limit: isize="+isize+"; max="+PREFS.maxTotalBytesForDoc+"; ctlen="+ctlen);
 143                 blacklisted = true;
 144               } else {
 145                 setByteCounterForDomWindow(dw, isize);
 146               }
 147             }
 148           } catch (e) {
 149             // httpChannel.getResponseHeader can throw when download is blocked (like font), just get out of here
 150             return;
 151           }
 152         }
 153         // check rules
 154         let rule = null;
 155         if (!blacklisted) {
 156           // check if we have too much images for this DOM window
 157           if (PREFS.debugLog) conlog("*** [", httpChannel.URI.spec, "] searching for rule...");
 158           rule = getRuleForURI(httpChannel.URI, bro.currentURI);
 159           if (rule) {
 160             if (PREFS.debugLog) conlog("*** [", httpChannel.URI.spec, "] rule: ", rule);
 161             if (rule.stopAction) {
 162               if (rule.action === "deny") {
 163                 if (PREFS.debugLog) conlog("*** [", httpChannel.URI.spec, "] blocked by 'deny' rule!");
 164                 blacklisted = true;
 165               }
 166             }
 167           }
 168         }
 169         //conlog("bl: [", httpChannel.URI.spec, "]: ", blacklisted);
 170         // check for 1st-party images
 171         if (!blacklisted && PREFS.allowFirstPartyImages && !bro.currentURI.equals(httpChannel.URI)) {
 172           // i've seen "Error: NS_ERROR_FAILURE: Component returned failure code: 0x80004005 (NS_ERROR_FAILURE) [nsIURI.host]" there, so...
 173           try {
 174             if (tldsvc.getBaseDomain(bro.currentURI) === tldsvc.getBaseDomain(httpChannel.URI)) {
 175               if (PREFS.debugLog) conlog(httpChannel.URI.spec, ": first-party!");
 176               return;
 177             }
 178           } catch (e) {}
 179         }
 180         //if (PREFS.debugLog) conlog("counting: ", httpChannel.URI.spec);
 181         let nlst = new ImgDetectListener(isoctet, blacklisted, doSizeBlockInTamper);
 182         nlst.rule = rule;
 183         nlst.mainURI = bro.currentURI;
 184         aSubject.QueryInterface(Ci.nsITraceableChannel);
 185         nlst.olst = aSubject.setNewListener(nlst);
 186         nlst.inited();
 187         // onStartRequest() and onStopRequest() will be called anyway, and
 188         // our tamper will process that correctly for blacklisted images
 189         if (blacklisted) aSubject.cancel(Cr.NS_BINDING_ABORTED);
 190       } else {
 191         if (PREFS.debugLog) conlog("WTF: ", httpChannel.URI.spec, " (", httpChannel.responseStatus, ")");
 192         //aSubject.cancel(Cr.NS_BINDING_ABORTED);
 193         resetImageStatus(httpChannel.URI, docURI);
 194       }
 195     } else if (aTopic === "http-on-modify-request") {
 196       let httpChannel = aSubject.QueryInterface(Ci.nsIHttpChannel);
 197       let url = httpChannel.URI.spec;
 198       // WARNING! `isManualReloadURL()` modifies internal URL cache (i.e. it is destructive!)
 199       if (isManualReloadURL(url)) {
 200         // ah, ok, i took time from rfc
 201         httpChannel.setRequestHeader("If-Modified-Since", "Sat, 29 Oct 1994 19:43:31 GMT", false);
 202         httpChannel.setRequestHeader("ETag", "", false);
 203         //delete reloadUrlList[url]; // no need to, `isManualReloadURL()` will do it for us
 204       }
 205     }
 206   },
 207 };
 208
 209
 210 //////////////////////////////////////////////////////////////////////////////
 211 let osvc = Cc["@mozilla.org/observer-service;1"].getService(Ci.nsIObserverService);
 212 osvc.addObserver(httpRequestObserver, "http-on-examine-response", false);
 213 osvc.addObserver(httpRequestObserver, "http-on-modify-request", false);