Auto merge of #24340 - jdm:image-cache-cors, r=Manishearth

Allow using CORS filtered image responses as WebGL textures

More specifically, this makes the "is this image same origin?" check consider the CORS status of the original response, rather than relying on an overly-strict "is this image's response's URL same-origin with a particular global?" check. To do this, we make the image cache double keyed based on the requested URL as well as the requesting origin, and store the CORS status of the eventual response with the final image that eventually gets sent to the HTMLImageElement consumer.

---
- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix #24330 and fix #24368
- [x] There are tests for these changes

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1 files changed, 52 insertions, 10 deletions

diff --git a/components/script/dom/canvasrenderingcontext2d.rs b/components/script/dom/canvasrenderingcontext2d.rs
index 1faf9878b53..c964422c27c 100644
--- a/components/script/dom/canvasrenderingcontext2d.rs
+++ b/components/script/dom/canvasrenderingcontext2d.rs
@@ -19,11 +19,13 @@ use crate::dom::bindings::root::{Dom, DomRoot, LayoutDom};
 use crate::dom::bindings::str::DOMString;
 use crate::dom::canvasgradient::{CanvasGradient, CanvasGradientStyle, ToFillOrStrokeStyle};
 use crate::dom::canvaspattern::CanvasPattern;
+use crate::dom::element::cors_setting_for_element;
 use crate::dom::element::Element;
 use crate::dom::globalscope::GlobalScope;
 use crate::dom::htmlcanvaselement::{CanvasContext, HTMLCanvasElement};
 use crate::dom::imagedata::ImageData;
 use crate::dom::node::{Node, NodeDamage};
+use crate::dom::paintworkletglobalscope::PaintWorkletGlobalScope;
 use crate::dom::textmetrics::TextMetrics;
 use crate::unpremultiplytable::UNPREMULTIPLY_TABLE;
 use canvas_traits::canvas::{Canvas2dMsg, CanvasId, CanvasMsg};
@@ -44,10 +46,11 @@ use net_traits::image_cache::ImageOrMetadataAvailable;
 use net_traits::image_cache::ImageResponse;
 use net_traits::image_cache::ImageState;
 use net_traits::image_cache::UsePlaceholder;
+use net_traits::request::CorsSettings;
 use pixels::PixelFormat;
 use profile_traits::ipc as profiled_ipc;
 use script_traits::ScriptMsg;
-use servo_url::ServoUrl;
+use servo_url::{ImmutableOrigin, ServoUrl};
 use std::cell::Cell;
 use std::str::FromStr;
 use std::sync::Arc;
@@ -126,6 +129,7 @@ pub struct CanvasState {
     /// The base URL for resolving CSS image URL values.
     /// Needed because of https://github.com/servo/servo/issues/17625
     base_url: ServoUrl,
+    origin: ImmutableOrigin,
     /// Any missing image URLs.
     missing_image_urls: DomRefCell<Vec<ServoUrl>>,
     saved_states: DomRefCell<Vec<CanvasContextState>>,
@@ -143,6 +147,14 @@ impl CanvasState {
             .unwrap();
         let (ipc_renderer, canvas_id) = receiver.recv().unwrap();
         debug!("Done.");
+        // Worklets always receive a unique origin. This messes with fetching
+        // cached images in the case of paint worklets, since the image cache
+        // is keyed on the origin requesting the image data.
+        let origin = if global.is::<PaintWorkletGlobalScope>() {
+            global.api_base_url().origin()
+        } else {
+            global.origin().immutable().clone()
+        };
         CanvasState {
             ipc_renderer: ipc_renderer,
             canvas_id: canvas_id,
@@ -152,6 +164,7 @@ impl CanvasState {
             base_url: global.api_base_url(),
             missing_image_urls: DomRefCell::new(Vec::new()),
             saved_states: DomRefCell::new(Vec::new()),
+            origin,
         }
     }
 
@@ -199,8 +212,12 @@ impl CanvasState {
         }
     }
 
-    fn fetch_image_data(&self, url: ServoUrl) -> Option<(Vec<u8>, Size2D<u32>)> {
-        let img = match self.request_image_from_cache(url) {
+    fn fetch_image_data(
+        &self,
+        url: ServoUrl,
+        cors_setting: Option<CorsSettings>,
+    ) -> Option<(Vec<u8>, Size2D<u32>)> {
+        let img = match self.request_image_from_cache(url, cors_setting) {
             ImageResponse::Loaded(img, _) => img,
             ImageResponse::PlaceholderLoaded(_, _) |
             ImageResponse::None |
@@ -218,10 +235,15 @@ impl CanvasState {
         Some((image_data, image_size))
     }
 
-    #[inline]
-    fn request_image_from_cache(&self, url: ServoUrl) -> ImageResponse {
+    fn request_image_from_cache(
+        &self,
+        url: ServoUrl,
+        cors_setting: Option<CorsSettings>,
+    ) -> ImageResponse {
         let response = self.image_cache.find_image_or_metadata(
             url.clone(),
+            self.origin.clone(),
+            cors_setting,
             UsePlaceholder::No,
             CanRequestImages::No,
         );
@@ -341,13 +363,28 @@ impl CanvasState {
                 // If the image argument is an HTMLImageElement object that is in the broken state,
                 // then throw an InvalidStateError exception
                 let url = image.get_url().ok_or(Error::InvalidState)?;
-                self.fetch_and_draw_image_data(htmlcanvas, url, sx, sy, sw, sh, dx, dy, dw, dh)
+                let cors_setting = cors_setting_for_element(image.upcast());
+                self.fetch_and_draw_image_data(
+                    htmlcanvas,
+                    url,
+                    cors_setting,
+                    sx,
+                    sy,
+                    sw,
+                    sh,
+                    dx,
+                    dy,
+                    dw,
+                    dh,
+                )
             },
             CanvasImageSource::CSSStyleValue(ref value) => {
                 let url = value
                     .get_url(self.base_url.clone())
                     .ok_or(Error::InvalidState)?;
-                self.fetch_and_draw_image_data(htmlcanvas, url, sx, sy, sw, sh, dx, dy, dw, dh)
+                self.fetch_and_draw_image_data(
+                    htmlcanvas, url, None, sx, sy, sw, sh, dx, dy, dw, dh,
+                )
             },
         };
 
@@ -423,6 +460,7 @@ impl CanvasState {
         &self,
         canvas: Option<&HTMLCanvasElement>,
         url: ServoUrl,
+        cors_setting: Option<CorsSettings>,
         sx: f64,
         sy: f64,
         sw: Option<f64>,
@@ -433,7 +471,9 @@ impl CanvasState {
         dh: Option<f64>,
     ) -> ErrorResult {
         debug!("Fetching image {}.", url);
-        let (mut image_data, image_size) = self.fetch_image_data(url).ok_or(Error::InvalidState)?;
+        let (mut image_data, image_size) = self
+            .fetch_image_data(url, cors_setting)
+            .ok_or(Error::InvalidState)?;
         pixels::rgba8_premultiply_inplace(&mut image_data);
         let image_size = image_size.to_f64();
 
@@ -776,7 +816,9 @@ impl CanvasState {
                 // then throw an InvalidStateError exception
                 image
                     .get_url()
-                    .and_then(|url| self.fetch_image_data(url))
+                    .and_then(|url| {
+                        self.fetch_image_data(url, cors_setting_for_element(image.upcast()))
+                    })
                     .ok_or(Error::InvalidState)?
             },
             CanvasImageSource::HTMLCanvasElement(ref canvas) => {
@@ -788,7 +830,7 @@ impl CanvasState {
             },
             CanvasImageSource::CSSStyleValue(ref value) => value
                 .get_url(self.base_url.clone())
-                .and_then(|url| self.fetch_image_data(url))
+                .and_then(|url| self.fetch_image_data(url, None))
                 .ok_or(Error::InvalidState)?,
         };