script/dom/processingoptions.rs
1/* This Source Code Form is subject to the terms of the Mozilla Public
2 * License, v. 2.0. If a copy of the MPL was not distributed with this
3 * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
4
5use std::str::FromStr;
6
7use base::id::WebViewId;
8use cssparser::match_ignore_ascii_case;
9use http::header::HeaderMap;
10use hyper_serde::Serde;
11use mime::Mime;
12use net_traits::fetch::headers::get_decode_and_split_header_name;
13use net_traits::mime_classifier::{MediaType, MimeClassifier};
14use net_traits::policy_container::PolicyContainer;
15use net_traits::request::{
16 CorsSettings, Destination, Initiator, InsecureRequestsPolicy, PreloadId, PreloadKey, Referrer,
17 RequestBuilder, RequestClient, RequestId,
18};
19use net_traits::response::{Response, ResponseBody};
20use net_traits::{
21 CoreResourceMsg, FetchMetadata, NetworkError, ReferrerPolicy, ResourceFetchTiming,
22};
23pub use nom_rfc8288::complete::LinkDataOwned as LinkHeader;
24use nom_rfc8288::complete::link_lenient as parse_link_header;
25use servo_url::{ImmutableOrigin, ServoUrl};
26use strum::IntoStaticStr;
27
28use crate::dom::bindings::inheritance::Castable;
29use crate::dom::bindings::refcounted::Trusted;
30use crate::dom::bindings::reflector::DomGlobal;
31use crate::dom::bindings::root::DomRoot;
32use crate::dom::csp::{GlobalCspReporting, Violation};
33use crate::dom::document::Document;
34use crate::dom::element::Element;
35use crate::dom::globalscope::GlobalScope;
36use crate::dom::medialist::MediaList;
37use crate::dom::node::NodeTraits;
38use crate::dom::performance::performanceresourcetiming::InitiatorType;
39use crate::dom::types::HTMLLinkElement;
40use crate::fetch::create_a_potential_cors_request;
41use crate::network_listener::{FetchResponseListener, ResourceTimingListener, submit_timing};
42use crate::script_runtime::CanGc;
43
44trait ValueForKeyInLinkHeader {
45 fn has_key_in_link_header(&self, key: &str) -> bool;
46 fn value_for_key_in_link_header(&self, key: &str) -> Option<&str>;
47}
48
49impl ValueForKeyInLinkHeader for LinkHeader {
50 fn has_key_in_link_header(&self, key: &str) -> bool {
51 self.params.iter().any(|p| p.key == key)
52 }
53 fn value_for_key_in_link_header(&self, key: &str) -> Option<&str> {
54 let param = self.params.iter().find(|p| p.key == key)?;
55 param.val.as_deref()
56 }
57}
58
59#[derive(PartialEq)]
60pub(crate) enum LinkProcessingPhase {
61 Media,
62 PreMedia,
63}
64
65/// <https://html.spec.whatwg.org/multipage/#link-processing-options>
66#[derive(Debug)]
67pub(crate) struct LinkProcessingOptions {
68 /// <https://html.spec.whatwg.org/multipage/#link-options-href>
69 pub(crate) href: String,
70 /// <https://html.spec.whatwg.org/multipage/#link-options-destination>
71 pub(crate) destination: Destination,
72 /// <https://html.spec.whatwg.org/multipage/#link-options-integrity>
73 pub(crate) integrity: String,
74 /// <https://html.spec.whatwg.org/multipage/#link-options-type>
75 pub(crate) link_type: String,
76 /// <https://html.spec.whatwg.org/multipage/#link-options-nonce>
77 pub(crate) cryptographic_nonce_metadata: String,
78 /// <https://html.spec.whatwg.org/multipage/#link-options-crossorigin>
79 pub(crate) cross_origin: Option<CorsSettings>,
80 /// <https://html.spec.whatwg.org/multipage/#link-options-referrer-policy>
81 pub(crate) referrer_policy: ReferrerPolicy,
82 /// <https://html.spec.whatwg.org/multipage/#link-options-policy-container>
83 pub(crate) policy_container: PolicyContainer,
84 /// <https://html.spec.whatwg.org/multipage/#link-options-source-set>
85 pub(crate) source_set: Option<()>,
86 /// <https://html.spec.whatwg.org/multipage/#link-options-base-url>
87 pub(crate) base_url: ServoUrl,
88 /// <https://html.spec.whatwg.org/multipage/#link-options-origin>
89 pub(crate) origin: ImmutableOrigin,
90 pub(crate) insecure_requests_policy: InsecureRequestsPolicy,
91 pub(crate) has_trustworthy_ancestor_origin: bool,
92 pub(crate) referrer: Referrer,
93 // https://html.spec.whatwg.org/multipage/#link-options-environment
94 pub(crate) request_client: RequestClient,
95 // https://html.spec.whatwg.org/multipage/#link-options-document
96 // TODO
97 // https://html.spec.whatwg.org/multipage/#link-options-on-document-ready
98 // TODO
99 // https://html.spec.whatwg.org/multipage/#link-options-fetch-priority
100 // TODO
101}
102
103impl LinkProcessingOptions {
104 /// <https://html.spec.whatwg.org/multipage/#apply-link-options-from-parsed-header-attributes>
105 fn apply_link_options_from_parsed_header(
106 &mut self,
107 link_object: &LinkHeader,
108 rel: &str,
109 ) -> bool {
110 // Step 1. If rel is "preload":
111 if rel == "preload" {
112 // Step 1.1. If attribs["as"] does not exist, then return false.
113 let Some(as_) = link_object.value_for_key_in_link_header("as") else {
114 return false;
115 };
116 // Step 1.2. Let destination be the result of translating attribs["as"].
117 let Some(destination) = Self::translate_a_preload_destination(as_) else {
118 // Step 1.3. If destination is null, then return false.
119 return false;
120 };
121 // Step 1.4. Set options's destination to destination.
122 self.destination = destination;
123 }
124 // Step 2. If attribs["crossorigin"] exists and is an ASCII case-insensitive match for one of the
125 // CORS settings attribute keywords, then set options's crossorigin to the CORS settings attribute
126 // state corresponding to that keyword.
127 if let Some(cross_origin) = link_object.value_for_key_in_link_header("crossorigin") {
128 self.cross_origin = determine_cors_settings_for_token(cross_origin);
129 }
130 // Step 3. If attribs["integrity"] exists, then set options's integrity to attribs["integrity"].
131 if let Some(integrity) = link_object.value_for_key_in_link_header("integrity") {
132 self.integrity = integrity.to_owned();
133 }
134 // Step 4. If attribs["referrerpolicy"] exists and is an ASCII case-insensitive match for
135 // some referrer policy, then set options's referrer policy to that referrer policy.
136 if let Some(referrer_policy) = link_object.value_for_key_in_link_header("referrerpolicy") {
137 self.referrer_policy = ReferrerPolicy::from(referrer_policy);
138 }
139 // Step 5. If attribs["nonce"] exists, then set options's nonce to attribs["nonce"].
140 if let Some(nonce) = link_object.value_for_key_in_link_header("nonce") {
141 self.cryptographic_nonce_metadata = nonce.to_owned();
142 }
143 // Step 6. If attribs["type"] exists, then set options's type to attribs["type"].
144 if let Some(link_type) = link_object.value_for_key_in_link_header("type") {
145 self.link_type = link_type.to_owned();
146 }
147 // Step 7. If attribs["fetchpriority"] exists and is an ASCII case-insensitive match
148 // for a fetch priority attribute keyword, then set options's fetch priority to that
149 // fetch priority attribute keyword.
150 // TODO
151 // Step 8. Return true.
152 true
153 }
154
155 /// <https://html.spec.whatwg.org/multipage/#process-a-link-header>
156 fn process_link_header(self, rel: &str, document: &Document) {
157 if rel == "preload" {
158 // https://html.spec.whatwg.org/multipage/#link-type-preload:process-a-link-header
159 // The process a link header step for this type of link given a link processing options options
160 // is to preload options.
161 if !self.type_matches_destination() {
162 return;
163 }
164 self.preload(document.window().webview_id(), None, document);
165 }
166 }
167
168 /// <https://html.spec.whatwg.org/multipage/#translate-a-preload-destination>
169 pub(crate) fn translate_a_preload_destination(
170 potential_destination: &str,
171 ) -> Option<Destination> {
172 // Step 2. Return the result of translating destination.
173 Some(match potential_destination {
174 "fetch" => Destination::None,
175 "font" => Destination::Font,
176 "image" => Destination::Image,
177 "script" => Destination::Script,
178 "style" => Destination::Style,
179 "track" => Destination::Track,
180 // Step 1. If destination is not "fetch", "font", "image",
181 // "script", "style", or "track", then return null.
182 _ => return None,
183 })
184 }
185
186 /// <https://html.spec.whatwg.org/multipage/#create-a-link-request>
187 pub(crate) fn create_link_request(self, webview_id: WebViewId) -> Option<RequestBuilder> {
188 // Step 1. Assert: options's href is not the empty string.
189 assert!(!self.href.is_empty());
190
191 // Step 3. Let url be the result of encoding-parsing a URL given options's href, relative to options's base URL.
192 let Ok(url) = ServoUrl::parse_with_base(Some(&self.base_url), &self.href) else {
193 // Step 4. If url is failure, then return null.
194 return None;
195 };
196
197 // Step 5. Let request be the result of creating a potential-CORS request given
198 // url, options's destination, and options's crossorigin.
199 // Step 6. Set request's policy container to options's policy container.
200 // Step 7. Set request's integrity metadata to options's integrity.
201 // Step 8. Set request's cryptographic nonce metadata to options's cryptographic nonce metadata.
202 // Step 9. Set request's referrer policy to options's referrer policy.
203 // Step 10. Set request's client to options's environment.
204 // FIXME: Step 11. Set request's priority to options's fetch priority.
205 let builder = create_a_potential_cors_request(
206 Some(webview_id),
207 url,
208 self.destination,
209 self.cross_origin,
210 None,
211 self.referrer,
212 )
213 .insecure_requests_policy(self.insecure_requests_policy)
214 .has_trustworthy_ancestor_origin(self.has_trustworthy_ancestor_origin)
215 .policy_container(self.policy_container)
216 .client(self.request_client)
217 .initiator(Initiator::Link)
218 .origin(self.origin)
219 .integrity_metadata(self.integrity)
220 .cryptographic_nonce_metadata(self.cryptographic_nonce_metadata)
221 .referrer_policy(self.referrer_policy);
222
223 // Step 12. Return request.
224 Some(builder)
225 }
226
227 /// <https://html.spec.whatwg.org/multipage/#match-preload-type>
228 pub(crate) fn type_matches_destination(&self) -> bool {
229 // Step 1. If type is an empty string, then return true.
230 if self.link_type.is_empty() {
231 return true;
232 }
233 // Step 2. If destination is "fetch", then return true.
234 //
235 // Fetch is handled as an empty string destination in the spec:
236 // https://fetch.spec.whatwg.org/#concept-potential-destination-translate
237 let destination = self.destination;
238 if destination == Destination::None {
239 return true;
240 }
241 // Step 3. Let mimeTypeRecord be the result of parsing type.
242 let Ok(mime_type_record) = Mime::from_str(&self.link_type) else {
243 // Step 4. If mimeTypeRecord is failure, then return false.
244 return false;
245 };
246 // Step 5. If mimeTypeRecord is not supported by the user agent, then return false.
247 //
248 // We currently don't check if we actually support the mime type. Only if we can classify
249 // it according to the spec.
250 let Some(mime_type) = MimeClassifier::get_media_type(&mime_type_record) else {
251 return false;
252 };
253 // Step 6. If any of the following are true:
254 if
255 // destination is "audio" or "video", and mimeTypeRecord is an audio or video MIME type;
256 ((destination == Destination::Audio || destination == Destination::Video) &&
257 mime_type == MediaType::AudioVideo)
258 // destination is a script-like destination and mimeTypeRecord is a JavaScript MIME type;
259 || (destination.is_script_like() && mime_type == MediaType::JavaScript)
260 // destination is "image" and mimeTypeRecord is an image MIME type;
261 || (destination == Destination::Image && mime_type == MediaType::Image)
262 // destination is "font" and mimeTypeRecord is a font MIME type;
263 || (destination == Destination::Font && mime_type == MediaType::Font)
264 // destination is "json" and mimeTypeRecord is a JSON MIME type;
265 || (destination == Destination::Json && mime_type == MediaType::Json)
266 // destination is "style" and mimeTypeRecord's essence is text/css; or
267 || (destination == Destination::Style && mime_type_record == mime::TEXT_CSS)
268 // destination is "track" and mimeTypeRecord's essence is text/vtt,
269 || (destination == Destination::Track && mime_type_record.essence_str() == "text/vtt")
270 {
271 // then return true.
272 return true;
273 }
274 // Step 7. Return false.
275 false
276 }
277
278 /// <https://html.spec.whatwg.org/multipage/#preload>
279 pub(crate) fn preload(
280 self,
281 webview_id: WebViewId,
282 link: Option<Trusted<HTMLLinkElement>>,
283 document: &Document,
284 ) {
285 // Step 1. If options's type doesn't match options's destination, then return.
286 //
287 // Handled by callers, since we need to check the previous destination type
288 assert!(self.type_matches_destination());
289 // Step 2. If options's destination is "image" and options's source set is not null,
290 // then set options's href to the result of selecting an image source from options's source set.
291 // TODO
292 // Step 3. Let request be the result of creating a link request given options.
293 let Some(request) = self.create_link_request(webview_id) else {
294 // Step 4. If request is null, then return.
295 return;
296 };
297 let preload_id = PreloadId::default();
298 let request = request.preload_id(preload_id.clone());
299 // Step 5. Let unsafeEndTime be 0.
300 // TODO
301 // Step 6. Let entry be a new preload entry whose integrity metadata is options's integrity.
302 //
303 // This is performed in `CoreResourceManager::fetch`
304 // Step 7. Let key be the result of creating a preload key given request.
305 let key = PreloadKey::new(&request);
306 // Step 8. If options's document is "pending", then set request's initiator type to "early hint".
307 // TODO
308 // Step 9. Let controller be null.
309 // Step 10. Let reportTiming given a Document document be to report timing for controller
310 // given document's relevant global object.
311 let url = request.url.clone();
312 let fetch_context = LinkFetchContext {
313 url,
314 link,
315 document: Trusted::new(document),
316 global: Trusted::new(&document.global()),
317 type_: LinkFetchContextType::Preload(key.clone()),
318 response_body: vec![],
319 };
320 document.insert_preloaded_resource(key, preload_id);
321 // Step 11. Set controller to the result of fetching request, with processResponseConsumeBody
322 // set to the following steps given a response response and null, failure, or a byte sequence bodyBytes:
323 document.fetch_background(request, fetch_context);
324 }
325}
326
327pub(crate) fn determine_cors_settings_for_token(token: &str) -> Option<CorsSettings> {
328 match_ignore_ascii_case! { token,
329 "anonymous" => Some(CorsSettings::Anonymous),
330 "use-credentials" => Some(CorsSettings::UseCredentials),
331 _ => None,
332 }
333}
334
335/// <https://html.spec.whatwg.org/multipage/#extract-links-from-headers>
336pub(crate) fn extract_links_from_headers(headers: &Option<Serde<HeaderMap>>) -> Vec<LinkHeader> {
337 // Step 1. Let links be a new list.
338 let mut links = Vec::new();
339 let Some(headers) = headers else {
340 return links;
341 };
342 // Step 2. Let rawLinkHeaders be the result of getting, decoding, and splitting `Link` from headers.
343 let Some(raw_link_headers) = get_decode_and_split_header_name("Link", headers) else {
344 return links;
345 };
346 // Step 3. For each linkHeader of rawLinkHeaders:
347 for link_header in raw_link_headers {
348 // Step 3.1. Let linkObject be the result of parsing linkHeader. [WEBLINK]
349 let Ok(parsed_link_header) = parse_link_header(&link_header) else {
350 continue;
351 };
352 for link_object in parsed_link_header {
353 let Some(link_object) = link_object else {
354 // Step 3.2. If linkObject["target_uri"] does not exist, then continue.
355 continue;
356 };
357 // Step 3.3. Append linkObject to links.
358 links.push(link_object.to_owned());
359 }
360 }
361 // Step 4. Return links.
362 links
363}
364
365/// <https://html.spec.whatwg.org/multipage/#process-link-headers>
366pub(crate) fn process_link_headers(
367 link_headers: &[LinkHeader],
368 document: &Document,
369 phase: LinkProcessingPhase,
370) {
371 let global = document.owner_global();
372 // Step 1. Let links be the result of extracting links from response's header list.
373 //
374 // Already performed once when parsing headers by caller
375 // Step 2. For each linkObject in links:
376 for link_object in link_headers {
377 // Step 2.1. Let rel be linkObject["relation_type"].
378 let Some(rel) = link_object.value_for_key_in_link_header("rel") else {
379 continue;
380 };
381 // Step 2.2. Let attribs be linkObject["target_attributes"].
382 //
383 // Not applicable, that's in `link_object.params`
384 // Step 2.3. Let expectedPhase be "media" if either "srcset", "imagesrcset",
385 // or "media" exist in attribs; otherwise "pre-media".
386 let expected_phase = if link_object.has_key_in_link_header("srcset") ||
387 link_object.has_key_in_link_header("imagesrcset") ||
388 link_object.has_key_in_link_header("media")
389 {
390 LinkProcessingPhase::Media
391 } else {
392 LinkProcessingPhase::PreMedia
393 };
394 // Step 2.4. If expectedPhase is not phase, then continue.
395 if expected_phase != phase {
396 continue;
397 }
398 // Step 2.5. If attribs["media"] exists and attribs["media"] does not match the environment, then continue.
399 if let Some(media) = link_object.value_for_key_in_link_header("media") {
400 if !MediaList::matches_environment(document, media) {
401 continue;
402 }
403 }
404 // Step 2.6. Let options be a new link processing options with
405 let mut options = LinkProcessingOptions {
406 href: link_object.url.clone(),
407 destination: Destination::None,
408 integrity: String::new(),
409 link_type: String::new(),
410 cryptographic_nonce_metadata: String::new(),
411 cross_origin: None,
412 referrer_policy: ReferrerPolicy::EmptyString,
413 policy_container: document.policy_container().to_owned(),
414 source_set: None,
415 origin: document.origin().immutable().to_owned(),
416 base_url: document.base_url(),
417 insecure_requests_policy: document.insecure_requests_policy(),
418 has_trustworthy_ancestor_origin: document.has_trustworthy_ancestor_or_current_origin(),
419 request_client: global.request_client(),
420 referrer: global.get_referrer(),
421 };
422 // Step 2.7. Apply link options from parsed header attributes to options given attribs and rel.
423 // If that returned false, then return.
424 if !options.apply_link_options_from_parsed_header(link_object, rel) {
425 return;
426 }
427 // Step 2.8. If attribs["imagesrcset"] exists and attribs["imagesizes"] exists,
428 // then set options's source set to the result of creating a source set given
429 // linkObject["target_uri"], attribs["imagesrcset"], attribs["imagesizes"], and null.
430 // TODO
431 // Step 2.9. Run the process a link header steps for rel given options.
432 options.process_link_header(rel, document);
433 }
434}
435
436#[derive(Clone, IntoStaticStr)]
437#[strum(serialize_all = "lowercase")]
438pub(crate) enum LinkFetchContextType {
439 Prefetch,
440 Preload(PreloadKey),
441}
442
443impl From<LinkFetchContextType> for InitiatorType {
444 fn from(other: LinkFetchContextType) -> Self {
445 let name: &'static str = other.into();
446 InitiatorType::LocalName(name.to_owned())
447 }
448}
449
450pub(crate) struct LinkFetchContext {
451 /// The `<link>` element (if any) that caused this fetch
452 pub(crate) link: Option<Trusted<HTMLLinkElement>>,
453
454 pub(crate) global: Trusted<GlobalScope>,
455 pub(crate) document: Trusted<Document>,
456
457 /// The url being prefetched
458 pub(crate) url: ServoUrl,
459
460 /// The type of fetching we perform, used when report timings.
461 pub(crate) type_: LinkFetchContextType,
462
463 pub(crate) response_body: Vec<u8>,
464}
465
466impl FetchResponseListener for LinkFetchContext {
467 fn process_request_body(&mut self, _: RequestId) {}
468
469 fn process_request_eof(&mut self, _: RequestId) {}
470
471 fn process_response(
472 &mut self,
473 _: RequestId,
474 fetch_metadata: Result<FetchMetadata, NetworkError>,
475 ) {
476 _ = fetch_metadata;
477 }
478
479 fn process_response_chunk(&mut self, _: RequestId, mut chunk: Vec<u8>) {
480 if matches!(self.type_, LinkFetchContextType::Preload(..)) {
481 self.response_body.append(&mut chunk);
482 }
483 }
484
485 /// Step 7 of <https://html.spec.whatwg.org/multipage/#link-type-prefetch:fetch-and-process-the-linked-resource-2>
486 /// and step 3.1 of <https://html.spec.whatwg.org/multipage/#link-type-preload:fetch-and-process-the-linked-resource-2>
487 fn process_response_eof(
488 mut self,
489 _: RequestId,
490 response_result: Result<(), NetworkError>,
491 timing: ResourceFetchTiming,
492 ) {
493 // Steps for https://html.spec.whatwg.org/multipage/#preload
494 if let LinkFetchContextType::Preload(key) = &self.type_ {
495 let response = if response_result.is_ok() {
496 // Step 11.1. If bodyBytes is a byte sequence, then set response's body to bodyBytes as a body.
497 let response = Response::new(self.url.clone(), timing.clone());
498 *response.body.lock() = ResponseBody::Done(std::mem::take(&mut self.response_body));
499 response
500 } else {
501 // Step 11.2. Otherwise, set response to a network error.
502 Response::network_error(NetworkError::ResourceLoadError("Failed to preload".into()))
503 };
504 // Step 11.5. If entry's on response available is null, then set entry's response to response;
505 // otherwise call entry's on response available given response.
506 // Step 12. Let commit be the following steps given a Document document:
507 // Step 12.1. If entry's response is not null, then call reportTiming given document.
508 // Step 12.2. Set document's map of preloaded resources[key] to entry.
509 // Step 13. If options's document is null, then set options's on document ready to commit. Otherwise, call commit with options's document.
510 let document = self.document.root();
511 let document_preloaded_resources = document.preloaded_resources();
512 let Some(preload_id) = document_preloaded_resources.get(key) else {
513 unreachable!(
514 "Must only be able to lookup preloaded resources if they already exist in document"
515 );
516 };
517 let _ = self.global.root().core_resource_thread().send(
518 CoreResourceMsg::StorePreloadedResponse(preload_id.clone(), response),
519 );
520 }
521
522 submit_timing(&self, &response_result, &timing, CanGc::note());
523
524 // Step 11.6. If processResponse is given, then call processResponse with response.
525 //
526 // Part of Preload
527 //
528 // Step 6. Let processPrefetchResponse be the following steps given a response response and null, failure, or a byte sequence bytesOrNull:
529 //
530 // Part of Prefetch
531 if let Some(link) = self.link.as_ref() {
532 link.root()
533 .fire_event_after_response(response_result, CanGc::note());
534 }
535 }
536
537 fn process_csp_violations(&mut self, _request_id: RequestId, violations: Vec<Violation>) {
538 let global = &self.resource_timing_global();
539 let source_position = self.link.as_ref().map(|link| {
540 let link = link.root();
541 link.upcast::<Element>()
542 .compute_source_position(link.line_number())
543 });
544 global.report_csp_violations(violations, None, source_position);
545 }
546}
547
548impl ResourceTimingListener for LinkFetchContext {
549 fn resource_timing_information(&self) -> (InitiatorType, ServoUrl) {
550 (self.type_.clone().into(), self.url.clone())
551 }
552
553 fn resource_timing_global(&self) -> DomRoot<GlobalScope> {
554 self.global.root()
555 }
556}