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use ::log::{error, info, log};
use rocket::http::{self, uri::Origin, Status};
use rocket::{self, error_, info_, log_, Outcome, Request};
use crate::{
actual_request_response, origin, preflight_response, request_headers, validate, Cors, Error,
};
enum CorsValidation {
Success,
Failure,
}
pub(crate) fn fairing_error_route<'r>(
request: &'r Request<'_>,
_: rocket::Data,
) -> rocket::handler::Outcome<'r> {
let status = request
.get_param::<u16>(0)
.unwrap_or(Ok(0))
.unwrap_or_else(|e| {
error_!("Fairing Error Handling Route error: {:?}", e);
500
});
let status = Status::from_code(status).unwrap_or_else(|| Status::InternalServerError);
Outcome::Failure(status)
}
fn fairing_route(rank: isize) -> rocket::Route {
rocket::Route::ranked(rank, http::Method::Get, "/<status>", fairing_error_route)
}
fn route_to_fairing_error_handler(options: &Cors, status: u16, request: &mut Request<'_>) {
let origin = Origin::parse_owned(format!("{}/{}", options.fairing_route_base, status)).unwrap();
request.set_method(http::Method::Get);
request.set_uri(origin);
}
fn on_response_wrapper(
options: &Cors,
request: &Request<'_>,
response: &mut rocket::Response<'_>,
) -> Result<(), Error> {
let origin = match origin(request)? {
None => {
return Ok(());
}
Some(origin) => origin,
};
let result = request.local_cache(|| unreachable!("This should not be executed so late"));
if let &CorsValidation::Failure = result {
return Ok(());
}
let cors_response = if request.method() == http::Method::Options {
let headers = request_headers(request)?;
preflight_response(options, &origin, headers.as_ref())
} else {
actual_request_response(options, &origin)
};
cors_response.merge(response);
if request.method() == http::Method::Options && request.route().is_none() {
info_!(
"CORS Fairing: Turned missing route {} into an OPTIONS pre-flight request",
request
);
response.set_status(Status::NoContent);
let _ = response.take_body();
}
Ok(())
}
impl rocket::fairing::Fairing for Cors {
fn info(&self) -> rocket::fairing::Info {
rocket::fairing::Info {
name: "CORS",
kind: rocket::fairing::Kind::Attach
| rocket::fairing::Kind::Request
| rocket::fairing::Kind::Response,
}
}
fn on_attach(&self, rocket: rocket::Rocket) -> Result<rocket::Rocket, rocket::Rocket> {
match self.validate() {
Ok(()) => Ok(rocket.mount(
&self.fairing_route_base,
vec![fairing_route(self.fairing_route_rank)],
)),
Err(e) => {
error_!("Error attaching CORS fairing: {}", e);
Err(rocket)
}
}
}
fn on_request(&self, request: &mut Request<'_>, _: &rocket::Data) {
let result = match validate(self, request) {
Ok(_) => CorsValidation::Success,
Err(err) => {
error_!("CORS Error: {}", err);
let status = err.status();
route_to_fairing_error_handler(self, status.code, request);
CorsValidation::Failure
}
};
let _ = request.local_cache(|| result);
}
fn on_response(&self, request: &Request<'_>, response: &mut rocket::Response<'_>) {
if let Err(err) = on_response_wrapper(self, request, response) {
error_!("Fairings on_response error: {}\nMost likely a bug", err);
response.set_status(Status::InternalServerError);
let _ = response.take_body();
}
}
}
#[cfg(test)]
mod tests {
use rocket::http::{Method, Status};
use rocket::local::Client;
use rocket::Rocket;
use crate::{AllOrSome, AllowedHeaders, AllowedOrigins, Cors};
const CORS_ROOT: &'static str = "/my_cors";
fn make_cors_options() -> Cors {
let (allowed_origins, failed_origins) = AllowedOrigins::some(&["https://www.acme.com"]);
assert!(failed_origins.is_empty());
Cors {
allowed_origins: allowed_origins,
allowed_methods: vec![Method::Get].into_iter().map(From::from).collect(),
allowed_headers: AllowedHeaders::some(&["Authorization", "Accept"]),
allow_credentials: true,
fairing_route_base: CORS_ROOT.to_string(),
..Default::default()
}
}
fn rocket(fairing: Cors) -> Rocket {
Rocket::ignite().attach(fairing)
}
#[test]
fn fairing_error_route_returns_passed_in_status() {
let client = Client::new(rocket(make_cors_options())).expect("to not fail");
let request = client.get(format!("{}/403", CORS_ROOT));
let response = request.dispatch();
assert_eq!(Status::Forbidden, response.status());
}
#[test]
fn fairing_error_route_returns_500_for_unknown_status() {
let client = Client::new(rocket(make_cors_options())).expect("to not fail");
let request = client.get(format!("{}/999", CORS_ROOT));
let response = request.dispatch();
assert_eq!(Status::InternalServerError, response.status());
}
#[test]
fn error_route_is_mounted_on_attach() {
let rocket = rocket(make_cors_options());
let expected_uri = format!("{}/<status>", CORS_ROOT);
let error_route = rocket
.routes()
.find(|r| r.method == Method::Get && r.uri.to_string() == expected_uri);
assert!(error_route.is_some());
}
#[test]
#[should_panic(expected = "launch fairing failure")]
fn options_are_validated_on_attach() {
let mut options = make_cors_options();
options.allowed_origins = AllOrSome::All;
options.send_wildcard = true;
let _ = rocket(options).launch();
}
}