1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899
//! Module containing the [`Policy`] trait and types that implement it.
use std::fmt;
use std::borrow::Cow;
use indexmap::IndexMap;
use rocket_http::{ext::IntoCollection, private::SmallVec};
use time::Duration;
use crate::http::{Header, uri::Absolute, uncased::{UncasedStr, Uncased}};
/// Trait implemented by security and privacy policy headers.
///
/// Types that implement this trait can be [`enable()`]d and [`disable()`]d on
/// instances of [`Shield`].
///
/// [`Shield`]: crate::shield::Shield
/// [`enable()`]: crate::shield::Shield::enable()
/// [`disable()`]: crate::shield::Shield::disable()
pub trait Policy: Default + Send + Sync + 'static {
/// The actual name of the HTTP header.
///
/// This name must uniquely identify the header as it is used to determine
/// whether two implementations of `Policy` are for the same header. Use the
/// real HTTP header's name.
///
/// # Example
///
/// ```rust
/// # extern crate rocket;
/// # use rocket::http::Header;
/// use rocket::shield::Policy;
///
/// #[derive(Default)]
/// struct MyPolicy;
///
/// impl Policy for MyPolicy {
/// const NAME: &'static str = "X-My-Policy";
/// # fn header(&self) -> Header<'static> { unimplemented!() }
/// }
/// ```
const NAME: &'static str;
/// Returns the [`Header`](../../rocket/http/struct.Header.html) to attach
/// to all outgoing responses.
///
/// # Example
///
/// ```rust
/// # extern crate rocket;
/// use rocket::http::Header;
/// use rocket::shield::Policy;
///
/// #[derive(Default)]
/// struct MyPolicy;
///
/// impl Policy for MyPolicy {
/// # const NAME: &'static str = "X-My-Policy";
/// fn header(&self) -> Header<'static> {
/// Header::new(Self::NAME, "value-to-enable")
/// }
/// }
/// ```
fn header(&self) -> Header<'static>;
}
/// Hack to make `Policy` Object-Safe.
pub(crate) trait SubPolicy: Send + Sync {
fn name(&self) -> &'static UncasedStr;
fn header(&self) -> Header<'static>;
}
impl<P: Policy> SubPolicy for P {
fn name(&self) -> &'static UncasedStr {
P::NAME.into()
}
fn header(&self) -> Header<'static> {
Policy::header(self)
}
}
macro_rules! impl_policy {
($T:ty, $name:expr) => (
impl Policy for $T {
const NAME: &'static str = $name;
fn header(&self) -> Header<'static> {
self.into()
}
}
)
}
// Keep this in-sync with the top-level module docs.
impl_policy!(XssFilter, "X-XSS-Protection");
impl_policy!(NoSniff, "X-Content-Type-Options");
impl_policy!(Frame, "X-Frame-Options");
impl_policy!(Hsts, "Strict-Transport-Security");
impl_policy!(ExpectCt, "Expect-CT");
impl_policy!(Referrer, "Referrer-Policy");
impl_policy!(Prefetch, "X-DNS-Prefetch-Control");
impl_policy!(Permission, "Permissions-Policy");
/// The [Referrer-Policy] header: controls the value set by the browser for the
/// [Referer] header.
///
/// Tells the browser if it should send all or part of URL of the current page
/// to the next site the user navigates to via the [Referer] header. This can be
/// important for security as the URL itself might expose sensitive data, such
/// as a hidden file path or personal identifier.
///
/// [Referrer-Policy]: https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Referrer-Policy
/// [Referer]: https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Referer
pub enum Referrer {
/// Omits the `Referer` header (returned by [`Referrer::default()`]).
NoReferrer,
/// Omits the `Referer` header on connection downgrade i.e. following HTTP
/// link from HTTPS site (_Browser default_).
NoReferrerWhenDowngrade,
/// Only send the origin of part of the URL, e.g. the origin of
/// `https://foo.com/bob.html` is `https://foo.com`.
Origin,
/// Send full URL for same-origin requests, only send origin part when
/// replying to [cross-origin] requests.
///
/// [cross-origin]: https://developer.mozilla.org/en-US/docs/Web/HTTP/CORS
OriginWhenCrossOrigin,
/// Send full URL for same-origin requests only.
SameOrigin,
/// Only send origin part of URL, only send if protocol security level
/// remains the same e.g. HTTPS to HTTPS.
StrictOrigin,
/// Send full URL for same-origin requests. For cross-origin requests, only
/// send origin part of URL if protocol security level remains the same e.g.
/// HTTPS to HTTPS.
StrictOriginWhenCrossOrigin,
/// Send full URL for same-origin or cross-origin requests. _This will leak
/// the full URL of TLS protected resources to insecure origins. Use with
/// caution._
UnsafeUrl,
}
/// Defaults to [`Referrer::NoReferrer`]. Tells the browser to omit the
/// `Referer` header.
impl Default for Referrer {
fn default() -> Referrer {
Referrer::NoReferrer
}
}
impl From<&Referrer> for Header<'static> {
fn from(referrer: &Referrer) -> Self {
let policy_string = match referrer {
Referrer::NoReferrer => "no-referrer",
Referrer::NoReferrerWhenDowngrade => "no-referrer-when-downgrade",
Referrer::Origin => "origin",
Referrer::OriginWhenCrossOrigin => "origin-when-cross-origin",
Referrer::SameOrigin => "same-origin",
Referrer::StrictOrigin => "strict-origin",
Referrer::StrictOriginWhenCrossOrigin => "strict-origin-when-cross-origin",
Referrer::UnsafeUrl => "unsafe-url",
};
Header::new(Referrer::NAME, policy_string)
}
}
/// The [Expect-CT] header: enables reporting and/or enforcement of [Certificate
/// Transparency].
///
/// [Certificate Transparency] can detect and prevent the use of misissued,
/// malicious, or revoked TLS certificates. It solves a variety of problems with
/// public TLS/SSL certificate management and is valuable measure for all public
/// TLS applications.
///
/// If you're just [getting started] with certificate transparency, ensure that
/// your [site is in compliance][getting started] before you enable enforcement
/// with [`ExpectCt::Enforce`] or [`ExpectCt::ReportAndEnforce`]. Failure to do
/// so will result in the browser refusing to communicate with your application.
/// _You have been warned_.
///
/// [Expect-CT]: https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Expect-CT
/// [Certificate Transparency]: http://www.certificate-transparency.org/what-is-ct
/// [getting started]: http://www.certificate-transparency.org/getting-started
pub enum ExpectCt {
/// Enforce certificate compliance for the next [`Duration`]. Ensure that
/// your certificates are in compliance before turning on enforcement.
/// (_Shield_ default).
Enforce(Duration),
/// Report to `Absolute`, but do not enforce, compliance violations for the
/// next [`Duration`]. Doesn't provide any protection but is a good way make
/// sure things are working correctly before turning on enforcement in
/// production.
Report(Duration, Absolute<'static>),
/// Enforce compliance and report violations to `Absolute` for the next
/// [`Duration`].
ReportAndEnforce(Duration, Absolute<'static>),
}
/// Defaults to [`ExpectCt::Enforce`] with a 30 day duration, enforce CT
/// compliance, see [draft] standard for more.
///
/// [draft]: https://tools.ietf.org/html/draft-ietf-httpbis-expect-ct-03#page-15
impl Default for ExpectCt {
fn default() -> ExpectCt {
ExpectCt::Enforce(Duration::days(30))
}
}
impl From<&ExpectCt> for Header<'static> {
fn from(expect: &ExpectCt) -> Self {
let policy_string = match expect {
ExpectCt::Enforce(age) => format!("max-age={}, enforce", age.whole_seconds()),
ExpectCt::Report(age, uri) => {
format!(r#"max-age={}, report-uri="{}""#, age.whole_seconds(), uri)
}
ExpectCt::ReportAndEnforce(age, uri) => {
format!("max-age={}, enforce, report-uri=\"{}\"", age.whole_seconds(), uri)
}
};
Header::new(ExpectCt::NAME, policy_string)
}
}
/// The [X-Content-Type-Options] header: turns off [mime sniffing] which can
/// prevent certain [attacks].
///
/// [mime sniffing]: https://developer.mozilla.org/en-US/docs/Web/HTTP/Basics_of_HTTP/MIME_types#MIME_sniffing
/// [X-Content-Type-Options]: https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/X-Content-Type-Options
/// [attacks]: https://blog.mozilla.org/security/2016/08/26/mitigating-mime-confusion-attacks-in-firefox/
pub enum NoSniff {
/// Turns off mime sniffing.
Enable,
}
/// Defaults to [`NoSniff::Enable`], turns off mime sniffing.
impl Default for NoSniff {
fn default() -> NoSniff {
NoSniff::Enable
}
}
impl From<&NoSniff> for Header<'static> {
fn from(_: &NoSniff) -> Self {
Header::new(NoSniff::NAME, "nosniff")
}
}
/// The HTTP [Strict-Transport-Security] (HSTS) header: enforces strict HTTPS
/// usage.
///
/// HSTS tells the browser that the site should only be accessed using HTTPS
/// instead of HTTP. HSTS prevents a variety of downgrading attacks and should
/// always be used when [TLS] is enabled. `Shield` will turn HSTS on and issue a
/// warning if you enable TLS without enabling HSTS when the application is run
/// in non-debug profiles.
///
/// While HSTS is important for HTTPS security, incorrectly configured HSTS can
/// lead to problems as you are disallowing access to non-HTTPS enabled parts of
/// your site. [Yelp engineering] has good discussion of potential challenges
/// that can arise and how to roll this out in a large scale setting. So, if
/// you use TLS, use HSTS, but roll it out with care.
///
/// [TLS]: https://rocket.rs/guide/configuration/#configuring-tls
/// [Strict-Transport-Security]: https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Strict-Transport-Security
/// [Yelp engineering]: https://engineeringblog.yelp.com/2017/09/the-road-to-hsts.html
#[derive(PartialEq, Copy, Clone)]
pub enum Hsts {
/// Browser should only permit this site to be accesses by HTTPS for the
/// next [`Duration`].
Enable(Duration),
/// Like [`Hsts::Enable`], but also apply to all of the site's subdomains.
IncludeSubDomains(Duration),
/// Send a "preload" HSTS header, which requests inclusion in the HSTS
/// preload list. This variant implies [`Hsts::IncludeSubDomains`], which
/// implies [`Hsts::Enable`].
///
/// The provided `Duration` must be _at least_ 365 days. If the duration
/// provided is less than 365 days, the header will be written out with a
/// `max-age` of 365 days.
///
/// # Details
///
/// Google maintains an [HSTS preload service] that can be used to prevent
/// the browser from ever connecting to your site over an insecure
/// connection. Read more at [MDN]. Don't enable this before you have
/// registered your site and you ensure that it meets the requirements
/// specified by the preload service.
///
/// [HSTS preload service]: https://hstspreload.org/
/// [MDN]: https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Strict-Transport-Security#Preloading_Strict_Transport_Security
Preload(Duration),
}
/// Defaults to `Hsts::Enable(Duration::days(365))`.
impl Default for Hsts {
fn default() -> Hsts {
Hsts::Enable(Duration::days(365))
}
}
impl From<&Hsts> for Header<'static> {
fn from(hsts: &Hsts) -> Self {
if hsts == &Hsts::default() {
static DEFAULT: Header<'static> = Header {
name: Uncased::from_borrowed(Hsts::NAME),
value: Cow::Borrowed("max-age=31536000")
};
return DEFAULT.clone();
}
let policy_string = match hsts {
Hsts::Enable(age) => format!("max-age={}", age.whole_seconds()),
Hsts::IncludeSubDomains(age) => {
format!("max-age={}; includeSubDomains", age.whole_seconds())
}
Hsts::Preload(age) => {
// Google says it needs to be >= 365 days for preload list.
static YEAR: Duration = Duration::seconds(31536000);
format!("max-age={}; includeSubDomains; preload", age.max(&YEAR).whole_seconds())
}
};
Header::new(Hsts::NAME, policy_string)
}
}
/// The [X-Frame-Options] header: helps prevent [clickjacking] attacks.
///
/// Controls whether the browser should allow the page to render in a `<frame>`,
/// [`<iframe>`][iframe] or `<object>`. This can be used to prevent
/// [clickjacking] attacks.
///
/// [X-Frame-Options]: https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/X-Frame-Options
/// [clickjacking]: https://en.wikipedia.org/wiki/Clickjacking
/// [owasp-clickjacking]: https://www.owasp.org/index.php/Clickjacking_Defense_Cheat_Sheet
/// [iframe]: https://developer.mozilla.org/en-US/docs/Web/HTML/Element/iframe
pub enum Frame {
/// Page cannot be displayed in a frame.
Deny,
/// Page can only be displayed in a frame if the page trying to render it is
/// in the same origin. Interpretation of same-origin is [browser
/// dependent][X-Frame-Options].
///
/// [X-Frame-Options]: https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/X-Frame-Options
SameOrigin,
}
/// Defaults to [`Frame::SameOrigin`].
impl Default for Frame {
fn default() -> Frame {
Frame::SameOrigin
}
}
impl From<&Frame> for Header<'static> {
fn from(frame: &Frame) -> Self {
let policy_string: &'static str = match frame {
Frame::Deny => "DENY",
Frame::SameOrigin => "SAMEORIGIN",
};
Header::new(Frame::NAME, policy_string)
}
}
/// The [X-XSS-Protection] header: filters some forms of reflected [XSS]
/// attacks. Modern browsers do not support or enforce this header.
///
/// [X-XSS-Protection]: https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/X-XSS-Protection
/// [XSS]: https://developer.mozilla.org/en-US/docs/Glossary/Cross-site_scripting
pub enum XssFilter {
/// Disables XSS filtering.
Disable,
/// Enables XSS filtering. If XSS is detected, the browser will sanitize
/// before rendering the page (_Shield default_).
Enable,
/// Enables XSS filtering. If XSS is detected, the browser will not
/// render the page.
EnableBlock,
}
/// Defaults to [`XssFilter::Enable`].
impl Default for XssFilter {
fn default() -> XssFilter {
XssFilter::Enable
}
}
impl From<&XssFilter> for Header<'static> {
fn from(filter: &XssFilter) -> Self {
let policy_string: &'static str = match filter {
XssFilter::Disable => "0",
XssFilter::Enable => "1",
XssFilter::EnableBlock => "1; mode=block",
};
Header::new(XssFilter::NAME, policy_string)
}
}
/// The [X-DNS-Prefetch-Control] header: controls browser DNS prefetching.
///
/// Tells the browser if it should perform domain name resolution on both links
/// that the user may choose to follow as well as URLs for items referenced by
/// the document including images, CSS, JavaScript, and so forth. Disabling
/// prefetching is useful if you don't control the link on the pages, or know
/// that you don't want to leak information to these domains.
///
/// [X-DNS-Prefetch-Control]: https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/X-DNS-Prefetch-Control
pub enum Prefetch {
/// Enables DNS prefetching. This is the browser default.
On,
/// Disables DNS prefetching. This is the shield policy default.
Off,
}
impl Default for Prefetch {
fn default() -> Prefetch {
Prefetch::Off
}
}
impl From<&Prefetch> for Header<'static> {
fn from(prefetch: &Prefetch) -> Self {
let policy_string = match prefetch {
Prefetch::On => "on",
Prefetch::Off => "off",
};
Header::new(Prefetch::NAME, policy_string)
}
}
/// The [Permissions-Policy] header: allow or block the use of browser features.
///
/// Tells the browser to allow or block the use of a browser feature in the
/// top-level page as well as allow or block _requesting access to_ (via the
/// `allow` `iframe` attribute) features in embedded iframes.
///
/// By default, the top-level page may access ~all features and any embedded
/// iframes may request access to ~any feature. This header allows the server to
/// control exactly _which_ (if any) origins may access or request access to
/// browser features.
///
/// Features are enabled via the [`Permission::allowed()`] constructor and
/// chainable [`allow()`](Self::allow()) build method. Features can be blocked
/// via the [`Permission::blocked()`] and chainable [`block()`](Self::block())
/// builder method.
///
/// ```rust
/// # #[macro_use] extern crate rocket;
/// use rocket::shield::{Shield, Permission, Feature, Allow};
///
/// // In addition to defaults, block access to geolocation and USB features.
/// // Enable camera and microphone features only for the serving origin. Enable
/// // payment request access for the current origin and `https://rocket.rs`.
/// let permission = Permission::default()
/// .block(Feature::Geolocation)
/// .block(Feature::Usb)
/// .allow(Feature::Camera, Allow::This)
/// .allow(Feature::Microphone, Allow::This)
/// .allow(Feature::Payment, [Allow::This, Allow::Origin(uri!("https://rocket.rs"))]);
///
/// rocket::build().attach(Shield::default().enable(permission));
/// ```
///
/// # Default
///
/// The default returned via [`Permission::default()`] blocks access to the
/// `interest-cohort` feature, otherwise known as FLoC, which disables using the
/// current site in ad targeting tracking computations.
///
/// [Permissions-Policy]: https://github.com/w3c/webappsec-permissions-policy/blob/a45df7b237e2a85e1909d7f226ca4eb4ce5095ba/permissions-policy-explainer.md
#[derive(PartialEq, Clone)]
pub struct Permission(IndexMap<Feature, Option<SmallVec<[Allow; 1]>>>);
impl Default for Permission {
/// The default `Permission` policy blocks access to the `interest-cohort`
/// feature, otherwise known as FLoC, which disables using the current site
/// in ad targeting tracking computations.
fn default() -> Self {
Permission::blocked(Feature::InterestCohort)
}
}
impl Permission {
/// Constructs a new `Permission` policy with only `feature` allowed for the
/// set of origins in `allow` which may be a single [`Allow`], a slice
/// (`[Allow]` or `&[Allow]`), or a vector (`Vec<Allow>`).
///
/// If `allow` is empty, the use of the feature is blocked unless another
/// call to `allow()` allows it. If `allow` contains [`Allow::Any`], the
/// feature is allowable for all origins. Otherwise, the feature is
/// allowable only for the origin specified in `allow`.
///
/// # Panics
///
/// Panics if an `Absolute` URI in an `Allow::Origin` does not contain a
/// host part.
///
/// # Example
///
/// ```rust
/// # #[macro_use] extern crate rocket;
/// use rocket::shield::{Permission, Feature, Allow};
///
/// let rocket = Allow::Origin(uri!("https://rocket.rs"));
///
/// let perm = Permission::allowed(Feature::Usb, Allow::This);
/// let perm = Permission::allowed(Feature::Usb, Allow::Any);
/// let perm = Permission::allowed(Feature::Usb, [Allow::This, rocket]);
/// ```
pub fn allowed<L>(feature: Feature, allow: L) -> Self
where L: IntoCollection<Allow>
{
Permission(IndexMap::new()).allow(feature, allow)
}
/// Constructs a new `Permission` policy with only `feature` blocked.
///
/// # Example
///
/// ```rust
/// use rocket::shield::{Permission, Feature};
///
/// let perm = Permission::blocked(Feature::Usb);
/// let perm = Permission::blocked(Feature::Payment);
/// ```
pub fn blocked(feature: Feature) -> Self {
Permission(IndexMap::new()).block(feature)
}
/// Adds `feature` as allowable for the set of origins in `allow` which may
/// be a single [`Allow`], a slice (`[Allow]` or `&[Allow]`), or a vector
/// (`Vec<Allow>`).
///
/// This policy supersedes any previous policy set for `feature`.
///
/// If `allow` is empty, the use of the feature is blocked unless another
/// call to `allow()` allows it. If `allow` contains [`Allow::Any`], the
/// feature is allowable for all origins. Otherwise, the feature is
/// allowable only for the origin specified in `allow`.
///
/// # Panics
///
/// Panics if an `Absolute` URI in an `Allow::Origin` does not contain a
/// host part.
///
/// # Example
///
/// ```rust
/// # #[macro_use] extern crate rocket;
/// use rocket::shield::{Permission, Feature, Allow};
///
/// let rocket = Allow::Origin(uri!("https://rocket.rs"));
/// let perm = Permission::allowed(Feature::Usb, Allow::This)
/// .allow(Feature::Payment, [rocket, Allow::This]);
/// ```
pub fn allow<L>(mut self, feature: Feature, allow: L) -> Self
where L: IntoCollection<Allow>
{
let mut allow = allow.into_collection();
if allow.contains(&Allow::Any) {
allow = Allow::Any.into_collection();
}
for allow in &allow {
if let Allow::Origin(absolute) = allow {
let auth = absolute.authority();
if auth.is_none() || matches!(auth, Some(a) if a.host().is_empty()) {
panic!("...")
}
}
}
self.0.insert(feature, Some(allow));
self
}
/// Blocks `feature`. This policy supersedes any previous policy set for
/// `feature`.
///
/// # Example
///
/// ```rust
/// use rocket::shield::{Permission, Feature};
///
/// let perm = Permission::default()
/// .block(Feature::Usb)
/// .block(Feature::Payment);
/// ```
pub fn block(mut self, feature: Feature) -> Self {
self.0.insert(feature, None);
self
}
/// Returns the allow list (so far) for `feature` if feature is allowed.
///
/// # Example
///
/// ```rust
/// use rocket::shield::{Permission, Feature, Allow};
///
/// let perm = Permission::default();
/// assert!(perm.get(Feature::Usb).is_none());
///
/// let perm = perm.allow(Feature::Usb, Allow::Any);
/// assert_eq!(perm.get(Feature::Usb).unwrap(), &[Allow::Any]);
/// ```
pub fn get(&self, feature: Feature) -> Option<&[Allow]> {
self.0.get(&feature)?.as_deref()
}
/// Returns an iterator over the pairs of features and their allow lists,
/// `None` if the feature is blocked.
///
/// Features are returned in the order in which they were first added.
///
/// # Example
///
/// ```rust
/// # #[macro_use] extern crate rocket;
/// use rocket::shield::{Permission, Feature, Allow};
///
/// let foo = uri!("https://foo.com:1234");
/// let perm = Permission::blocked(Feature::Camera)
/// .allow(Feature::Gyroscope, [Allow::This, Allow::Origin(foo.clone())])
/// .block(Feature::Payment)
/// .allow(Feature::Camera, Allow::Any);
///
/// let perms: Vec<_> = perm.iter().collect();
/// assert_eq!(perms.len(), 3);
/// assert_eq!(perms, vec![
/// (Feature::Camera, Some(&[Allow::Any][..])),
/// (Feature::Gyroscope, Some(&[Allow::This, Allow::Origin(foo)][..])),
/// (Feature::Payment, None),
/// ]);
/// ```
pub fn iter(&self) -> impl Iterator<Item = (Feature, Option<&[Allow]>)> {
self.0.iter().map(|(feature, list)| (*feature, list.as_deref()))
}
}
impl From<&Permission> for Header<'static> {
fn from(perm: &Permission) -> Self {
if perm == &Permission::default() {
static DEFAULT: Header<'static> = Header {
name: Uncased::from_borrowed(Permission::NAME),
value: Cow::Borrowed("interest-cohort=()")
};
return DEFAULT.clone();
}
let value = perm.0.iter()
.map(|(feature, allow)| {
let list = allow.as_ref()
.into_iter()
.flatten()
.map(|origin| origin.rendered())
.collect::<Vec<_>>()
.join(" ");
format!("{}=({})", feature, list)
})
.collect::<Vec<_>>()
.join(", ");
Header::new(Permission::NAME, value)
}
}
/// Specifies the origin(s) allowed to access a browser [`Feature`] via
/// [`Permission`].
#[derive(Debug, PartialEq, Clone)]
pub enum Allow {
/// Allow this specific origin. The feature is allowed only for this
/// specific origin.
///
/// The `user_info`, `path`, and `query` parts of the URI, if any, are
/// ignored.
Origin(Absolute<'static>),
/// Any origin at all.
///
/// The feature will be allowed in all browsing contexts regardless of their
/// origin.
Any,
/// The current origin.
///
/// The feature will be allowed in the immediately returned document and in
/// all nested browsing contexts (iframes) in the same origin.
This,
}
impl Allow {
fn rendered(&self) -> Cow<'static, str> {
match self {
Allow::Origin(uri) => {
let mut string = String::with_capacity(32);
string.push('"');
string.push_str(uri.scheme());
// This should never fail when rendering a header for `Shield`
// due to `panic` in `.allow()`.
if let Some(auth) = uri.authority() {
use std::fmt::Write;
let _ = write!(string, "://{}", auth.host());
if let Some(port) = auth.port() {
let _ = write!(string, ":{}", port);
}
}
string.push('"');
string.into()
}
Allow::Any => "*".into(),
Allow::This => "self".into(),
}
}
}
/// A browser feature that can be enabled or blocked via [`Permission`].
#[derive(Debug, PartialEq, Eq, Hash, Copy, Clone)]
#[non_exhaustive]
pub enum Feature {
// Standardized.
/// The "accelerometer" feature.
Accelerometer,
/// The "ambient-light-sensor" feature.
AmbientLightSensor,
/// The "autoplay" feature.
Autoplay,
/// The "battery" feature.
Battery,
/// The "camera" feature.
Camera,
/// The "cross-origin-isolated" feature.
CrossOriginIsolated,
/// The "display-capture" feature.
Displaycapture,
/// The "document-domain" feature.
DocumentDomain,
/// The "encrypted-media" feature.
EncryptedMedia,
/// The "execution-while-not-rendered" feature.
ExecutionWhileNotRendered,
/// The "execution-while-out-of-viewport" feature.
ExecutionWhileOutOfviewport,
/// The "fullscreen" feature.
Fullscreen,
/// The "geolocation" feature.
Geolocation,
/// The "gyroscope" feature.
Gyroscope,
/// The "magnetometer" feature.
Magnetometer,
/// The "microphone" feature.
Microphone,
/// The "midi" feature.
Midi,
/// The "navigation-override" feature.
NavigationOverride,
/// The "payment" feature.
Payment,
/// The "picture-in-picture" feature.
PictureInPicture,
/// The "publickey-credentials-get" feature.
PublickeyCredentialsGet,
/// The "screen-wake-lock" feature.
ScreenWakeLock,
/// The "sync-xhr" feature.
SyncXhr,
/// The "usb" feature.
Usb,
/// The "web-share" feature.
WebShare,
/// The "xr-spatial-tracking" feature.
XrSpatialTracking,
// Proposed.
/// The "clipboard-read" feature.
ClipboardRead,
/// The "clipboard-write" feature.
ClipboardWrite,
/// The "gamepad" feature.
Gamepad,
/// The "speaker-selection" feature.
SpeakerSelection,
/// The "interest-cohort" feature.
InterestCohort,
// Experimental.
/// The "conversion-measurement" feature.
ConversionMeasurement,
/// The "focus-without-user-activation" feature.
FocusWithoutUserActivation,
/// The "hid" feature.
Hid,
/// The "idle-detection" feature.
IdleDetection,
/// The "serial" feature.
Serial,
/// The "sync-script" feature.
SyncScript,
/// The "trust-token-redemption" feature.
TrustTokenRedemption,
/// The "vertical-scroll" feature.
VerticalScroll,
}
impl Feature {
/// Returns the feature string as it appears in the header.
///
/// # Example
///
/// ```rust
/// use rocket::shield::Feature;
///
/// assert_eq!(Feature::Camera.as_str(), "camera");
/// assert_eq!(Feature::SyncScript.as_str(), "sync-script");
/// ```
pub const fn as_str(self) -> &'static str {
use Feature::*;
match self {
Accelerometer => "accelerometer",
AmbientLightSensor => "ambient-light-sensor",
Autoplay => "autoplay",
Battery => "battery",
Camera => "camera",
CrossOriginIsolated => "cross-origin-isolated",
Displaycapture => "display-capture",
DocumentDomain => "document-domain",
EncryptedMedia => "encrypted-media",
ExecutionWhileNotRendered => "execution-while-not-rendered",
ExecutionWhileOutOfviewport => "execution-while-out-of-viewport",
Fullscreen => "fullscreen",
Geolocation => "geolocation",
Gyroscope => "gyroscope",
Magnetometer => "magnetometer",
Microphone => "microphone",
Midi => "midi",
NavigationOverride => "navigation-override",
Payment => "payment",
PictureInPicture => "picture-in-picture",
PublickeyCredentialsGet => "publickey-credentials-get",
ScreenWakeLock => "screen-wake-lock",
SyncXhr => "sync-xhr",
Usb => "usb",
WebShare => "web-share",
XrSpatialTracking => "xr-spatial-tracking",
ClipboardRead => "clipboard-read",
ClipboardWrite => "clipboard-write",
Gamepad => "gamepad",
SpeakerSelection => "speaker-selection",
InterestCohort => "interest-cohort",
ConversionMeasurement => "conversion-measurement",
FocusWithoutUserActivation => "focus-without-user-activation",
Hid => "hid",
IdleDetection => "idle-detection",
Serial => "serial",
SyncScript => "sync-script",
TrustTokenRedemption => "trust-token-redemption",
VerticalScroll => "vertical-scroll",
}
}
}
impl fmt::Display for Feature {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
self.as_str().fmt(f)
}
}