script/dom/

cookiestore.rs

/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at https://mozilla.org/MPL/2.0/. */

use std::borrow::Cow;
use std::collections::VecDeque;
use std::rc::Rc;

use cookie::{Cookie, SameSite};
use dom_struct::dom_struct;
use hyper_serde::Serde;
use itertools::Itertools;
use js::context::JSContext;
use js::jsval::NullValue;
use net_traits::CookieSource::NonHTTP;
use net_traits::{CookieAsyncResponse, CookieData, CoreResourceMsg};
use script_bindings::cell::DomRefCell;
use script_bindings::codegen::GenericBindings::CookieStoreBinding::CookieSameSite;
use script_bindings::reflector::reflect_dom_object;
use script_bindings::script_runtime::CanGc;
use servo_base::generic_channel::{GenericCallback, GenericSend, GenericSender};
use servo_base::id::CookieStoreId;
use servo_url::ServoUrl;
use time::OffsetDateTime;

use crate::dom::bindings::codegen::Bindings::CookieStoreBinding::{
    CookieInit, CookieListItem, CookieStoreDeleteOptions, CookieStoreGetOptions, CookieStoreMethods,
};
use crate::dom::bindings::error::Error;
use crate::dom::bindings::refcounted::Trusted;
use crate::dom::bindings::reflector::DomGlobal;
use crate::dom::bindings::root::DomRoot;
use crate::dom::bindings::str::USVString;
use crate::dom::document::get_registrable_domain_suffix_of_or_is_equal_to;
use crate::dom::eventtarget::EventTarget;
use crate::dom::globalscope::GlobalScope;
use crate::dom::promise::Promise;
use crate::dom::window::Window;
use crate::task_source::SendableTaskSource;

#[derive(JSTraceable, MallocSizeOf)]
struct DroppableCookieStore {
    // Store an id so that we can send it with requests and the resource thread knows who to respond to
    #[no_trace]
    store_id: CookieStoreId,
    #[no_trace]
    unregister_channel: GenericSender<CoreResourceMsg>,
}

impl Drop for DroppableCookieStore {
    fn drop(&mut self) {
        let res = self
            .unregister_channel
            .send(CoreResourceMsg::RemoveCookieListener(self.store_id));
        if res.is_err() {
            error!("Failed to send cookiestore message to resource threads");
        }
    }
}

/// <https://cookiestore.spec.whatwg.org/>
/// CookieStore provides an async API for pages and service workers to access and modify cookies.
/// This requires setting up communication with resource thread's cookie storage that allows for
/// the page to have multiple cookie storage promises in flight at the same time.
#[dom_struct]
pub(crate) struct CookieStore {
    eventtarget: EventTarget,
    #[conditional_malloc_size_of]
    in_flight: DomRefCell<VecDeque<Rc<Promise>>>,
    droppable: DroppableCookieStore,
}

struct CookieListener {
    // TODO:(whatwg/cookiestore#239) The spec is missing details for what task source to use
    task_source: SendableTaskSource,
    context: Trusted<CookieStore>,
}

impl CookieListener {
    pub(crate) fn handle(&self, message: CookieAsyncResponse) {
        let context = self.context.clone();
        self.task_source.queue(task!(cookie_message: move || {
            let Some(promise) = context.root().in_flight.borrow_mut().pop_front() else {
                warn!("No promise exists for cookie store response");
                return;
            };
            match message.data {
                CookieData::Get(cookie) => {
                    // If list is failure, then reject p with a TypeError and abort these steps.
                    // (There is currently no way for list to result in failure)
                    if let Some(cookie) = cookie {
                        // Otherwise, resolve p with the first item of list.
                        promise.resolve_native(&cookie_to_list_item(cookie.into_inner()), CanGc::deprecated_note());
                    } else {
                        // If list is empty, then resolve p with null.
                        promise.resolve_native(&NullValue(), CanGc::deprecated_note());
                    }
                },
                CookieData::GetAll(cookies) => {
                    // If list is failure, then reject p with a TypeError and abort these steps.
                    promise.resolve_native(
                        &cookies
                        .into_iter()
                        .map(|cookie| cookie_to_list_item(cookie.0))
                        .collect_vec(),
                    CanGc::deprecated_note());
                },
                CookieData::Delete(_) | CookieData::Change(_) | CookieData::Set(_) => {
                    promise.resolve_native(&(), CanGc::deprecated_note());
                }
            }
        }));
    }
}

impl CookieStore {
    fn new_inherited(unregister_channel: GenericSender<CoreResourceMsg>) -> CookieStore {
        CookieStore {
            eventtarget: EventTarget::new_inherited(),
            in_flight: Default::default(),
            droppable: DroppableCookieStore {
                store_id: CookieStoreId::new(),
                unregister_channel,
            },
        }
    }

    pub(crate) fn new(global: &GlobalScope, can_gc: CanGc) -> DomRoot<CookieStore> {
        let store = reflect_dom_object(
            Box::new(CookieStore::new_inherited(
                global.resource_threads().core_thread.clone(),
            )),
            global,
            can_gc,
        );
        store.setup_route();
        store
    }

    fn setup_route(&self) {
        let context = Trusted::new(self);
        let cs_listener = CookieListener {
            task_source: self
                .global()
                .task_manager()
                .dom_manipulation_task_source()
                .to_sendable(),
            context,
        };

        let callback = GenericCallback::new(move |message| match message {
            Ok(msg) => cs_listener.handle(msg),
            Err(err) => warn!("Error receiving a CookieStore message: {:?}", err),
        })
        .expect("Could not create cookie store callback");

        let res = self
            .global()
            .resource_threads()
            .send(CoreResourceMsg::NewCookieListener(
                self.droppable.store_id,
                callback,
                self.global().creation_url(),
            ));
        if res.is_err() {
            error!("Failed to send cookiestore message to resource threads");
        }
    }
}

/// <https://cookiestore.spec.whatwg.org/#create-a-cookielistitem>
fn cookie_to_list_item(cookie: Cookie) -> CookieListItem {
    // TODO: Investigate if we need to explicitly UTF-8 decode without BOM here or if thats
    // already being done by cookie-rs or implicitly by using rust strings
    CookieListItem {
        // Let name be the result of running UTF-8 decode without BOM on cookie’s name.
        name: Some(cookie.name().to_string().into()),

        // Let value be the result of running UTF-8 decode without BOM on cookie’s value.
        value: Some(cookie.value().to_string().into()),
    }
}

impl CookieStoreMethods<crate::DomTypeHolder> for CookieStore {
    /// <https://cookiestore.spec.whatwg.org/#dom-cookiestore-get>
    fn Get(&self, cx: &mut JSContext, name: USVString) -> Rc<Promise> {
        // 1. Let settings be this’s relevant settings object.
        let global = self.global();

        // 2. Let origin be settings’s origin.
        let origin = global.origin();

        // 5. Let p be a new promise.
        let p = Promise::new2(cx, &global);

        // 3. If origin is an opaque origin, then return a promise rejected with a "SecurityError" DOMException.
        if !origin.is_tuple() {
            p.reject_error_with_cx(cx, Error::Security(None));
            return p;
        }

        // 4. Let url be settings’s creation URL.
        let creation_url = global.creation_url();

        let name = CookieStore::normalize(&name);

        // 6. Run the following steps in parallel:
        let res = self
            .global()
            .resource_threads()
            .send(CoreResourceMsg::GetCookieDataForUrlAsync(
                self.droppable.store_id,
                creation_url,
                Some(name),
            ));
        if res.is_err() {
            error!("Failed to send cookiestore message to resource threads");
        } else {
            self.in_flight.borrow_mut().push_back(p.clone());
        }

        // 7. Return p.
        p
    }

    /// <https://cookiestore.spec.whatwg.org/#dom-cookiestore-get-options>
    fn Get_(&self, cx: &mut JSContext, options: &CookieStoreGetOptions) -> Rc<Promise> {
        // 1. Let settings be this’s relevant settings object.
        let global = self.global();

        // 2. Let origin be settings’s origin.
        let origin = global.origin();

        // 7. Let p be a new promise.
        let p = Promise::new2(cx, &global);

        // 3. If origin is an opaque origin, then return a promise rejected with a "SecurityError" DOMException.
        if !origin.is_tuple() {
            p.reject_error_with_cx(cx, Error::Security(None));
            return p;
        }

        // 4. Let url be settings’s creation URL.
        let creation_url = global.creation_url();

        // 5. If options is empty, then return a promise rejected with a TypeError.
        // "is empty" is not strictly defined anywhere in the spec but the only value we require here is "url"
        if options.url.is_none() && options.name.is_none() {
            p.reject_error_with_cx(cx, Error::Type(c"Options cannot be empty".to_owned()));
            return p;
        }

        let mut final_url = creation_url.clone();

        // 6. If options["url"] is present, then run these steps:
        if let Some(get_url) = &options.url {
            // 6.1. Let parsed be the result of parsing options["url"] with settings’s API base URL.
            let parsed_url = ServoUrl::parse_with_base(Some(&global.api_base_url()), get_url);

            // 6.2. If this’s relevant global object is a Window object and parsed does not equal url with exclude fragments set to true,
            // then return a promise rejected with a TypeError.
            if let Some(_window) = DomRoot::downcast::<Window>(self.global()) &&
                parsed_url
                    .as_ref()
                    .is_ok_and(|parsed| !parsed.is_equal_excluding_fragments(&creation_url))
            {
                p.reject_error_with_cx(cx, Error::Type(c"URL does not match context".to_owned()));
                return p;
            }

            // 6.3. If parsed’s origin and url’s origin are not the same origin,
            // then return a promise rejected with a TypeError.
            if parsed_url
                .as_ref()
                .is_ok_and(|parsed| creation_url.origin() != parsed.origin())
            {
                p.reject_error_with_cx(cx, Error::Type(c"Not same origin".to_owned()));
                return p;
            }

            // 6.4. Set url to parsed.
            if let Ok(url) = parsed_url {
                final_url = url;
            }
        }

        // 6. Run the following steps in parallel:
        let res = self
            .global()
            .resource_threads()
            .send(CoreResourceMsg::GetCookieDataForUrlAsync(
                self.droppable.store_id,
                final_url,
                options.name.clone().map(|val| CookieStore::normalize(&val)),
            ));
        if res.is_err() {
            error!("Failed to send cookiestore message to resource threads");
        } else {
            self.in_flight.borrow_mut().push_back(p.clone());
        }

        p
    }

    /// <https://cookiestore.spec.whatwg.org/#dom-cookiestore-getall>
    fn GetAll(&self, cx: &mut JSContext, name: USVString) -> Rc<Promise> {
        // 1. Let settings be this’s relevant settings object.
        let global = self.global();

        // 2. Let origin be settings’s origin.
        let origin = global.origin();

        // 5. Let p be a new promise.
        let p = Promise::new2(cx, &global);

        // 3. If origin is an opaque origin, then return a promise rejected with a "SecurityError" DOMException.
        if !origin.is_tuple() {
            p.reject_error_with_cx(cx, Error::Security(None));
            return p;
        }
        // 4. Let url be settings’s creation URL.
        let creation_url = global.creation_url();

        // Normalize name here rather than passing the un-nomarlized name around to the resource thread and back
        let name = CookieStore::normalize(&name);

        // 6. Run the following steps in parallel:
        let res =
            self.global()
                .resource_threads()
                .send(CoreResourceMsg::GetAllCookieDataForUrlAsync(
                    self.droppable.store_id,
                    creation_url,
                    Some(name),
                ));
        if res.is_err() {
            error!("Failed to send cookiestore message to resource threads");
        } else {
            self.in_flight.borrow_mut().push_back(p.clone());
        }

        // 7. Return p.
        p
    }

    /// <https://cookiestore.spec.whatwg.org/#dom-cookiestore-getall-options>
    fn GetAll_(&self, cx: &mut JSContext, options: &CookieStoreGetOptions) -> Rc<Promise> {
        // 1. Let settings be this’s relevant settings object.
        let global = self.global();

        // 2. Let origin be settings’s origin.
        let origin = global.origin();

        // 6. Let p be a new promise.
        let p = Promise::new2(cx, &global);

        // 3. If origin is an opaque origin, then return a promise rejected with a "SecurityError" DOMException.
        if !origin.is_tuple() {
            p.reject_error_with_cx(cx, Error::Security(None));
            return p;
        }

        // 4. Let url be settings’s creation URL.
        let creation_url = global.creation_url();

        let mut final_url = creation_url.clone();

        // 5. If options["url"] is present, then run these steps:
        if let Some(get_url) = &options.url {
            // 5.1. Let parsed be the result of parsing options["url"] with settings’s API base URL.
            let parsed_url = ServoUrl::parse_with_base(Some(&global.api_base_url()), get_url);

            // If this’s relevant global object is a Window object and parsed does not equal url with exclude fragments set to true,
            // then return a promise rejected with a TypeError.
            if let Some(_window) = DomRoot::downcast::<Window>(self.global()) &&
                parsed_url
                    .as_ref()
                    .is_ok_and(|parsed| !parsed.is_equal_excluding_fragments(&creation_url))
            {
                p.reject_error_with_cx(cx, Error::Type(c"URL does not match context".to_owned()));
                return p;
            }

            // 5.3. If parsed’s origin and url’s origin are not the same origin,
            // then return a promise rejected with a TypeError.
            if parsed_url
                .as_ref()
                .is_ok_and(|parsed| creation_url.origin() != parsed.origin())
            {
                p.reject_error_with_cx(cx, Error::Type(c"Not same origin".to_owned()));
                return p;
            }

            // 5.4. Set url to parsed.
            if let Ok(url) = parsed_url {
                final_url = url;
            }
        }

        // 7. Run the following steps in parallel:
        let res =
            self.global()
                .resource_threads()
                .send(CoreResourceMsg::GetAllCookieDataForUrlAsync(
                    self.droppable.store_id,
                    final_url,
                    options.name.clone().map(|val| CookieStore::normalize(&val)),
                ));
        if res.is_err() {
            error!("Failed to send cookiestore message to resource threads");
        } else {
            self.in_flight.borrow_mut().push_back(p.clone());
        }

        // 8. Return p
        p
    }

    /// <https://cookiestore.spec.whatwg.org/#dom-cookiestore-set>
    fn Set(&self, cx: &mut JSContext, name: USVString, value: USVString) -> Rc<Promise> {
        // 1. Let settings be this’s relevant settings object.
        let global = self.global();

        // 2. Let origin be settings’s origin.
        let origin = global.origin();

        // 9. Let p be a new promise.
        let p = Promise::new2(cx, &global);

        // 3. If origin is an opaque origin, then return a promise rejected with a "SecurityError" DOMException.
        if !origin.is_tuple() {
            p.reject_error_with_cx(cx, Error::Security(None));
            return p;
        }

        // 6.1 Let r be the result of running set a cookie with url, name, value, null, null, "/", "strict", false, and null.
        let properties = CookieInit {
            name,
            value,
            expires: None,
            domain: None,
            path: USVString(String::from("/")),
            sameSite: CookieSameSite::Strict,
            partitioned: false,
        };
        let creation_url = global.creation_url();
        let Some(cookie) = CookieStore::set_a_cookie(&creation_url, &properties) else {
            // If r is failure, then reject p with a TypeError and abort these steps.
            p.reject_error_with_cx(cx, Error::Type(c"Invalid cookie".to_owned()));
            return p;
        };

        // 6. Run the following steps in parallel:
        let res = self
            .global()
            .resource_threads()
            .send(CoreResourceMsg::SetCookieForUrlAsync(
                self.droppable.store_id,
                creation_url.clone(),
                Serde(cookie.into_owned()),
                NonHTTP,
            ));
        if res.is_err() {
            error!("Failed to send cookiestore message to resource threads");
        } else {
            self.in_flight.borrow_mut().push_back(p.clone());
        }

        // 7. Return p.
        p
    }

    /// <https://cookiestore.spec.whatwg.org/#dom-cookiestore-set-options>
    fn Set_(&self, cx: &mut JSContext, options: &CookieInit) -> Rc<Promise> {
        // 1. Let settings be this’s relevant settings object.
        let global = self.global();

        // 2. Let origin be settings’s origin.
        let origin = global.origin();

        // 5. Let p be a new promise.
        let p = Promise::new2(cx, &global);

        // 3. If origin is an opaque origin, then return a promise rejected with a "SecurityError" DOMException.
        if !origin.is_tuple() {
            p.reject_error_with_cx(cx, Error::Security(None));
            return p;
        }

        // 4. Let url be settings’s creation URL.
        let creation_url = global.creation_url();

        // 6.1. Let r be the result of running set a cookie with url, options["name"], options["value"],
        // options["expires"], options["domain"], options["path"], options["sameSite"], and options["partitioned"].
        let Some(cookie) = CookieStore::set_a_cookie(&creation_url, options) else {
            p.reject_error_with_cx(cx, Error::Type(c"Invalid cookie".to_owned()));
            return p;
        };

        // 6. Run the following steps in parallel:
        let res = self
            .global()
            .resource_threads()
            .send(CoreResourceMsg::SetCookieForUrlAsync(
                self.droppable.store_id,
                creation_url.clone(),
                Serde(cookie.into_owned()),
                NonHTTP,
            ));
        if res.is_err() {
            error!("Failed to send cookiestore message to resource threads");
        } else {
            self.in_flight.borrow_mut().push_back(p.clone());
        }

        // 7. Return p
        p
    }

    /// <https://cookiestore.spec.whatwg.org/#dom-cookiestore-delete>
    fn Delete(&self, cx: &mut JSContext, name: USVString) -> Rc<Promise> {
        // 1. Let settings be this’s relevant settings object.
        let global = self.global();

        // 2. Let origin be settings’s origin.
        let origin = global.origin();

        // 5. Let p be a new promise.
        let p = Promise::new2(cx, &global);

        // 3. If origin is an opaque origin, then return a promise rejected with a "SecurityError" DOMException.
        if !origin.is_tuple() {
            p.reject_error_with_cx(cx, Error::Security(None));
            return p;
        }

        // 6. Run the following steps in parallel:
        // TODO: the spec passes additional parameters to _delete a cookie_ that we don't handle yet
        let res = global
            .resource_threads()
            .send(CoreResourceMsg::DeleteCookieAsync(
                self.droppable.store_id,
                global.creation_url(),
                name.0,
            ));
        if res.is_err() {
            error!("Failed to send cookiestore message to resource threads");
        } else {
            self.in_flight.borrow_mut().push_back(p.clone());
        }

        // 7. Return p.
        p
    }

    /// <https://cookiestore.spec.whatwg.org/#dom-cookiestore-delete-options>
    fn Delete_(&self, cx: &mut JSContext, options: &CookieStoreDeleteOptions) -> Rc<Promise> {
        // 1. Let settings be this’s relevant settings object.
        let global = self.global();

        // 2. Let origin be settings’s origin.
        let origin = global.origin();

        // 5. Let p be a new promise.
        let p = Promise::new2(cx, &global);

        // 3. If origin is an opaque origin, then return a promise rejected with a "SecurityError" DOMException.
        if !origin.is_tuple() {
            p.reject_error_with_cx(cx, Error::Security(None));
            return p;
        }

        // 6. Run the following steps in parallel:
        // TODO: the spec passes additional parameters to _delete a cookie_ that we don't handle yet
        let res = global
            .resource_threads()
            .send(CoreResourceMsg::DeleteCookieAsync(
                self.droppable.store_id,
                global.creation_url(),
                options.name.to_string(),
            ));
        if res.is_err() {
            error!("Failed to send cookiestore message to resource threads");
        } else {
            self.in_flight.borrow_mut().push_back(p.clone());
        }

        // 7. Return p.
        p
    }
}

impl CookieStore {
    /// <https://cookiestore.spec.whatwg.org/#normalize-a-cookie-name-or-value>
    fn normalize(value: &USVString) -> String {
        value.trim_matches([' ', '\t']).into()
    }

    /// <https://cookiestore.spec.whatwg.org/#set-cookie-algorithm>
    fn set_a_cookie<'a>(url: &'a ServoUrl, properties: &'a CookieInit) -> Option<Cookie<'a>> {
        // 1. Normalize name.
        let name = CookieStore::normalize(&properties.name);
        // 2. Normalize value.
        let value = CookieStore::normalize(&properties.value);

        // 3. If name or value contain U+003B (;), any C0 control character except U+0009 TAB, or U+007F DELETE, then return failure.
        if CookieStore::contains_control_characters(&name) ||
            CookieStore::contains_control_characters(&value)
        {
            return None;
        }

        // 4. If name contains U+003D (=), then return failure.
        if name.contains('=') {
            return None;
        }

        // 5. If name’s length is 0:
        if name.is_empty() {
            // 5.1 If value contains U+003D (=), then return failure.
            // 5.2 If value’s length is 0, then return failure.
            if value.contains('=') || value.is_empty() {
                return None;
            }
            // 5.3 If value, byte-lowercased, starts with `__host-`, `__host-http-`, `__http-`, or `__secure-`, then return failure.
            let lowercased_value = value.to_ascii_lowercase();
            if ["__host-", "__host-http-", "__http-", "__secure-"]
                .iter()
                .any(|prefix| lowercased_value.starts_with(prefix))
            {
                return None;
            }
        }

        // 6. If name, byte-lowercased, starts with `__host-http-` or `__http-`, then return failure.
        let lowercased_name = name.to_ascii_lowercase();
        if lowercased_name.starts_with("__host-http-") || lowercased_name.starts_with("__http-") {
            return None;
        }

        // 9. If the byte sequence length of encodedName plus the byte sequence length of encodedValue is greater than the maximum name/value pair size, then return failure.
        if name.len() + value.len() > 4096 {
            return None;
        }

        let mut cookie = Cookie::build((Cow::Owned(name), Cow::Owned(value)))
            // 21. Append ('Secure', '') to attributes
            .secure(true)
            // 23. If partitioned is true, Append (`Partitioned`, ``) to attributes.
            .partitioned(properties.partitioned)
            // 21. Switch on sameSite:
            .same_site(match properties.sameSite {
                CookieSameSite::Lax => SameSite::Lax,
                CookieSameSite::Strict => SameSite::Strict,
                CookieSameSite::None => SameSite::None,
            });

        // 12. If domain is non-null
        if let Some(domain) = &properties.domain {
            // 10. Let host be url's host.
            let host = match url.host() {
                Some(host) => host.to_owned(),
                None => return None,
            };
            // 12.1 If domain starts with U+002E (.), then return failure
            if domain.starts_with('.') {
                return None;
            }
            // 12.2 If name, byte-lowercased, starts with `__host-`, then return failure.
            if lowercased_name.starts_with("__host-") {
                return None;
            }

            // 12.3 If domain is not a registrable domain suffix of and is not equal to host, then return failure.
            // 12.4 Let parsedDomain be the result of host parsing domain.
            // 12.5 Assert: parsedDomain is not failure.
            // Note: this function parses the host and returns the parsed host on success
            let domain = get_registrable_domain_suffix_of_or_is_equal_to(domain, host)?;

            // 12.6 Let encodedDomain be the result of UTF-8 encoding parsedDomain.
            let domain = domain.to_string();
            // 12.7 If the byte sequence length of encodedDomain is greater than the maximum attribute value size, then return failure.
            if domain.len() > 1024 {
                return None;
            }
            // 12.8 Append (`Domain`, encodedDomain) to attributes.
            cookie.inner_mut().set_domain(domain);
        }

        // 13. If expires is non-null:
        if let Some(expiry) = properties.expires {
            // TODO: update cookiestore to take new maxAge parameter
            // 13.2 Append (`Expires`, expires (date serialized)) to attributes.
            cookie.inner_mut().set_expires(
                OffsetDateTime::from_unix_timestamp((*expiry / 1000.0) as i64)
                    .expect("cookie expiry out of range"),
            );
        }

        // 15. If path is the empty string, then set path to the serialized cookie default path of url.
        let path = if properties.path.is_empty() {
            // 15.1 Let cloneURL be a clone of url.
            let mut cloned_url = url.clone();
            {
                // 15.2 Set cloneURL’s path to the cookie default path of cloneURL’s path.
                // <https://datatracker.ietf.org/doc/html/draft-ietf-httpbis-layered-cookies#name-cookie-default-path>
                let mut path_segments = cloned_url
                    .as_mut_url()
                    .path_segments_mut()
                    .expect("document creation url cannot be a base");
                // 2. If path's size is greater than 1, then remove path's last item
                if url.path_segments().is_some_and(|ps| ps.count() > 1) {
                    path_segments.pop();
                } else {
                    // 3. Otherwise, set path[0] to the empty string.
                    path_segments.clear();
                }
            }
            cloned_url.path().to_owned()
        } else {
            properties.path.to_string()
        };
        // 16. If path does not start with U+002F (/), then return failure.
        if !path.starts_with('/') {
            return None;
        }
        // 17. If path is not U+002F (/), and name, byte-lowercased, starts with `__host-`, then return failure.
        if path != "/" && lowercased_name.starts_with("__host-") {
            return None;
        }
        // 19. If the byte sequence length of encodedPath is greater than the maximum attribute value size, then return failure.
        if path.len() > 1024 {
            return None;
        }
        // 20. Append (`Path`, encodedPath) to attributes.
        cookie.inner_mut().set_path(path);

        Some(cookie.build())
    }

    /// <https://cookiestore.spec.whatwg.org/#set-cookie-algorithm>
    fn contains_control_characters(val: &str) -> bool {
        // If name or value contain U+003B (;), any C0 control character except U+0009 TAB, or U+007F DELETE, then return failure.
        val.contains(
            |v| matches!(v, '\u{0000}'..='\u{0008}' | '\u{000a}'..='\u{001f}' | '\u{007f}' | ';'),
        )
    }
}