Auto merge of #14865 - mrnayak:sri-fetch, r=jdm

Implement Subresource Integrity

Implemented response validation part of https://w3c.github.io/webappsec-subresource-integrity/.
Implemented step eighteen of the main fetch. If a request has integrity metadata, then following steps are performed
1) Wait for response body
2) If the response does not have a termination reason and response does not match request’s integrity metadata, set response and internalResponse to a network error.

Dependency updated: html5ever-atoms from 0.1.2 to 0.1.3. This will not completely fix #14523, It will implement changes related to response validation. Request validation algorithm implementation needs CSP.

I did not update any WPT-Test. In my local system, I found some assertion issue dependent on the order of execution of test-case. It would be helpful if someone could do "try" build on these changes to get wpt results.

r? @jdm
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1 files changed, 15 insertions, 3 deletions

diff --git a/components/script/dom/htmlscriptelement.rs b/components/script/dom/htmlscriptelement.rs
index 9558d9c4b41..9c2bcfd583c 100644
--- a/components/script/dom/htmlscriptelement.rs
+++ b/components/script/dom/htmlscriptelement.rs
@@ -40,7 +40,6 @@ use std::ascii::AsciiExt;
 use std::cell::Cell;
 use std::sync::{Arc, Mutex};
 use style::str::{HTML_SPACE_CHARACTERS, StaticStringVec};
-
 #[dom_struct]
 pub struct HTMLScriptElement {
     htmlelement: HTMLElement,
@@ -221,6 +220,7 @@ impl PreInvoke for ScriptContext {}
 fn fetch_a_classic_script(script: &HTMLScriptElement,
                           url: ServoUrl,
                           cors_setting: Option<CorsSettings>,
+                          integrity_metadata: String,
                           character_encoding: EncodingRef) {
     let doc = document_from_node(script);
 
@@ -245,6 +245,7 @@ fn fetch_a_classic_script(script: &HTMLScriptElement,
         pipeline_id: Some(script.global().pipeline_id()),
         referrer_url: Some(doc.url()),
         referrer_policy: doc.get_referrer_policy(),
+        integrity_metadata: integrity_metadata,
         .. RequestInit::default()
     };
 
@@ -365,7 +366,13 @@ impl HTMLScriptElement {
 
         // TODO: Step 15: Nonce.
 
-        // TODO: Step 16: Parser state.
+        // Step 16: Integrity Metadata
+        let im_attribute = element.get_attribute(&ns!(), &local_name!("integrity"));
+        let integrity_val = im_attribute.r().map(|a| a.value());
+        let integrity_metadata = match integrity_val {
+            Some(ref value) => &***value,
+            None => "",
+        };
 
         // TODO: Step 17: environment settings object.
 
@@ -393,7 +400,7 @@ impl HTMLScriptElement {
                 };
 
                 // Step 18.6.
-                fetch_a_classic_script(self, url, cors_setting, encoding);
+                fetch_a_classic_script(self, url, cors_setting, integrity_metadata.to_owned(), encoding);
 
                 true
             },
@@ -675,6 +682,11 @@ impl HTMLScriptElementMethods for HTMLScriptElement {
     // https://html.spec.whatwg.org/multipage/#dom-script-defer
     make_bool_setter!(SetDefer, "defer");
 
+    // https://html.spec.whatwg.org/multipage/#dom-script-integrity
+    make_getter!(Integrity, "integrity");
+    // https://html.spec.whatwg.org/multipage/#dom-script-integrity
+    make_setter!(SetIntegrity, "integrity");
+
     // https://html.spec.whatwg.org/multipage/#dom-script-event
     make_getter!(Event, "event");
     // https://html.spec.whatwg.org/multipage/#dom-script-event