aboutsummaryrefslogtreecommitdiff
diff options
context:
space:
mode:
-rw-r--r--bg/ExternalLicenses.js12
-rw-r--r--bg/ResponseProcessor.js22
-rw-r--r--main_background.js32
3 files changed, 43 insertions, 23 deletions
diff --git a/bg/ExternalLicenses.js b/bg/ExternalLicenses.js
index 6eda008..6d35863 100644
--- a/bg/ExternalLicenses.js
+++ b/bg/ExternalLicenses.js
@@ -48,7 +48,17 @@ const ExternalLicenses = {
cachedHrefs.delete(tabId);
},
- // Checks external script using web labels
+ /**
+ * Checks external script using web labels
+ *
+ * If the script cannot be found in the web labels table, returns null.
+ *
+ * If the script can be found in the web labels table, and at least
+ * one of its licenses can be found in our free license DB, returns
+ * "free".
+ *
+ * Otherwise returns "nonfree".
+ */
async check(script) {
const { url, tabId, frameId, documentUrl } = script;
const tabCache = cachedHrefs.get(tabId);
diff --git a/bg/ResponseProcessor.js b/bg/ResponseProcessor.js
index 3c90d9c..429b778 100644
--- a/bg/ResponseProcessor.js
+++ b/bg/ResponseProcessor.js
@@ -29,6 +29,11 @@ const { ResponseMetaData } = require('./ResponseMetaData');
const listeners = new WeakMap();
const webRequestEvent = browser.webRequest.onHeadersReceived;
+// Some hardcoded return values for the onHeadersReceived callback.
+const BLOCKING_RESPONSES = {
+ ACCEPT: {}, // Do nothing
+ REJECT: { cancel: true }, // Cancel the request. See docs of BlockingResponse
+};
class ResponseProcessor {
@@ -53,13 +58,6 @@ class ResponseProcessor {
}
}
-Object.assign(ResponseProcessor, {
- // control flow values to be returned by handler.pre() callbacks
- ACCEPT: {},
- REJECT: { cancel: true },
- CONTINUE: null
-});
-
class ResponseTextFilter {
constructor(request) {
this.request = request;
@@ -72,13 +70,16 @@ class ResponseTextFilter {
}
async process(handler) {
- if (!this.canProcess) return ResponseProcessor.ACCEPT;
+ if (!this.canProcess) return BlockingResponses.ACCEPT;
const { metaData, request } = this;
const response = { request, metaData }; // we keep it around allowing callbacks to store state
if (typeof handler.pre !== 'function' || typeof handler.post !== 'function') {
throw new Error('handler should have a pre and post function.');
}
+
+ // If can determine without checking and filtering response
+ // payload then return.
const res = await handler.pre(response);
if (res) return res;
@@ -132,8 +133,9 @@ class ResponseTextFilter {
filter.close();
}
- return ResponseProcessor.ACCEPT;
+ // Accepting the filtered payload.
+ return BLOCKING_RESPONSES.ACCEPT;
}
}
-module.exports = { ResponseProcessor };
+module.exports = { ResponseProcessor, BLOCKING_RESPONSES };
diff --git a/main_background.js b/main_background.js
index 49815d5..40a8397 100644
--- a/main_background.js
+++ b/main_background.js
@@ -22,7 +22,7 @@
*/
const checkLib = require('./common/checks.js');
-const { ResponseProcessor } = require('./bg/ResponseProcessor');
+const { ResponseProcessor, BLOCKING_RESPONSES } = require('./bg/ResponseProcessor');
const { Storage, ListStore, hash } = require('./common/Storage');
const { ListManager } = require('./bg/ListManager');
const { ExternalLicenses } = require('./bg/ExternalLicenses');
@@ -470,15 +470,23 @@ async function blockBlacklistedScripts(request) {
}
/**
-* This listener gets called as soon as we've got all the HTTP headers, can guess
-* content type and encoding, and therefore correctly parse HTML documents
-* and external script inclusions in search of non-free JavaScript
-*/
-
+ * An onHeadersReceived handler. See bg/ResponseProcessor.js for how
+ * it is used.
+ *
+ * This listener gets called as soon as we've got all the HTTP
+ * headers, can guess content type and encoding, and therefore
+ * correctly parse HTML documents and external script inclusions in
+ * search of non-free JavaScript
+ */
const ResponseHandler = {
/**
- * Enforce white/black lists for url/site early (hashes will be handled later)
- */
+ * Checks black/whitelists and web labels. Returns a
+ * BlockingResponse (if we can determine) or null (if further work
+ * is needed).
+ *
+ * Enforce white/black lists for url/site early (hashes will be
+ * handled later)
+ */
async pre(response) {
let { request } = response;
let { url, type, tabId, frameId, documentUrl } = request;
@@ -494,7 +502,7 @@ const ResponseHandler = {
if (blacklisted) {
if (type === 'script') {
// this shouldn't happen, because we intercept earlier in blockBlacklistedScripts()
- return ResponseProcessor.REJECT;
+ return BLOCKING_RESPONSES.REJECT;
}
if (type === 'main_frame') { // we handle the page change here too, since we won't call edit_html()
activityReports[tabId] = await createReport({ url: fullUrl, tabId });
@@ -520,12 +528,12 @@ const ResponseHandler = {
url: topUrl,
'whitelisted': [url, whitelistedSite ? `User whitelisted ${whitelistedSite}` : 'Whitelisted by user']
});
- return ResponseProcessor.ACCEPT;
+ return BLOCKING_RESPONSES.ACCEPT;
} else {
// Check for the weblabel method
const scriptInfo = await ExternalLicenses.check({ url: fullUrl, tabId, frameId, documentUrl });
if (scriptInfo) {
- const [verdict, ret] = scriptInfo.free ? ['accepted', ResponseProcessor.ACCEPT] : ['blocked', ResponseProcessor.REJECT];
+ const [verdict, ret] = scriptInfo.free ? ['accepted', BLOCKING_RESPONSES.ACCEPT] : ['blocked', BLOCKING_RESPONSES.REJECT];
const licenseIds = [...scriptInfo.licenses].map(l => l.identifier).sort().join(', ');
const msg = licenseIds
? `Free license${scriptInfo.licenses.size > 1 ? 's' : ''} (${licenseIds})`
@@ -538,7 +546,7 @@ const ResponseHandler = {
}
// it's a page (it's too early to report) or an unknown script:
// let's keep processing
- return ResponseProcessor.CONTINUE;
+ return null;
},
/**