Struct ContentSecurityPolicy 

pub struct ContentSecurityPolicy { /* private fields */ }

A Content-Security-Policy header, built directive by directive, and the layer that sends it.

Rails’ content_security_policy initializer as plain Rust: build the policy in src/lib.rs and add it to the router with .layer(policy) (generated apps do, in content_security_policy()). Every response gets the header unless the handler (or a layer closer to it) set one already, which is how routes override the global policy: give a nested router its own .layer(...), or return the header from the handler.

Sources are written as in the header: SELF, NONE, DATA, "https://unpkg.com", … NONCE stands for the request’s random nonce (see CspNonce). Calling a directive twice replaces it. report_only sends Content-Security-Policy-Report-Only instead, to try a policy without breaking pages; report_uri and report_to collect violations.

Free plan

A header per response and, when the policy uses NONCE, 16 random bytes per request: no binding call, microseconds of CPU.

Examples

use axum::{Router, routing::get};
use ocre::security::{ContentSecurityPolicy, DATA, NONCE, NONE, SELF};

let policy = ContentSecurityPolicy::new()
    .default_src(&[SELF])
    .script_src(&[SELF, NONCE, "https://unpkg.com"])
    .img_src(&[SELF, DATA])
    .object_src(&[NONE])
    .report_uri("/csp-reports");
assert_eq!(
    policy.header_value(Some("r4nd0m")),
    "default-src 'self'; script-src 'self' 'nonce-r4nd0m' https://unpkg.com; img-src 'self' data:; \
     object-src 'none'; report-uri /csp-reports"
);

let app: Router = Router::new().route("/", get(|| async { "home" })).layer(policy);

Implementations

impl ContentSecurityPolicy

pub fn new() -> Self

An empty policy: add directives with the builder methods.

Examples

assert_eq!(ocre::security::ContentSecurityPolicy::new().header_value(None), "");

pub fn directive(self, name: &str, sources: &[&str]) -> Self

Sets any directive, e.g. directive("sandbox", &["allow-forms"]); replaces a previous value.

An empty sources list writes the directive alone (upgrade-insecure-requests).

Examples

use ocre::security::{ContentSecurityPolicy, SELF};

let csp = ContentSecurityPolicy::new().directive("worker-src", &[SELF]).directive("worker-src", &["blob:"]);
assert_eq!(csp.header_value(None), "worker-src blob:");

pub fn default_src(self, sources: &[&str]) -> Self

default-src: the fallback for every fetch directive not set.

Examples

use ocre::security::{ContentSecurityPolicy, SELF};

assert_eq!(ContentSecurityPolicy::new().default_src(&[SELF]).header_value(None), "default-src 'self'");

pub fn script_src(self, sources: &[&str]) -> Self

script-src: where scripts may come from.

Examples

use ocre::security::{ContentSecurityPolicy, SELF};

let csp = ContentSecurityPolicy::new().script_src(&[SELF, "https://unpkg.com"]);
assert_eq!(csp.header_value(None), "script-src 'self' https://unpkg.com");

pub fn style_src(self, sources: &[&str]) -> Self

style-src: where stylesheets and inline styles may come from.

Examples

use ocre::security::{ContentSecurityPolicy, SELF, UNSAFE_INLINE};

let csp = ContentSecurityPolicy::new().style_src(&[SELF, UNSAFE_INLINE]);
assert_eq!(csp.header_value(None), "style-src 'self' 'unsafe-inline'");

pub fn img_src(self, sources: &[&str]) -> Self

img-src: images and favicons.

Examples

use ocre::security::{ContentSecurityPolicy, DATA, SELF};

assert_eq!(ContentSecurityPolicy::new().img_src(&[SELF, DATA]).header_value(None), "img-src 'self' data:");

pub fn font_src(self, sources: &[&str]) -> Self

font-src: web fonts.

Examples

use ocre::security::{ContentSecurityPolicy, SELF};

assert_eq!(ContentSecurityPolicy::new().font_src(&[SELF]).header_value(None), "font-src 'self'");

pub fn connect_src(self, sources: &[&str]) -> Self

connect-src: fetch, XHR (htmx requests), WebSockets and EventSource.

Examples

use ocre::security::{ContentSecurityPolicy, SELF};

assert_eq!(ContentSecurityPolicy::new().connect_src(&[SELF]).header_value(None), "connect-src 'self'");

pub fn media_src(self, sources: &[&str]) -> Self

media-src: <audio> and <video>.

Examples

use ocre::security::{ContentSecurityPolicy, SELF};

assert_eq!(ContentSecurityPolicy::new().media_src(&[SELF]).header_value(None), "media-src 'self'");

pub fn object_src(self, sources: &[&str]) -> Self

object-src: <object> and <embed>; set it to NONE.

Examples

use ocre::security::{ContentSecurityPolicy, NONE};

assert_eq!(ContentSecurityPolicy::new().object_src(&[NONE]).header_value(None), "object-src 'none'");

pub fn frame_src(self, sources: &[&str]) -> Self

frame-src: pages this app may put in an <iframe>.

Examples

use ocre::security::ContentSecurityPolicy;

let csp = ContentSecurityPolicy::new().frame_src(&["https://www.youtube-nocookie.com"]);
assert_eq!(csp.header_value(None), "frame-src https://www.youtube-nocookie.com");

pub fn frame_ancestors(self, sources: &[&str]) -> Self

frame-ancestors: sites that may put this app in a frame (the modern X-Frame-Options).

Examples

use ocre::security::{ContentSecurityPolicy, SELF};

assert_eq!(ContentSecurityPolicy::new().frame_ancestors(&[SELF]).header_value(None), "frame-ancestors 'self'");

pub fn form_action(self, sources: &[&str]) -> Self

form-action: where forms may be submitted.

Examples

use ocre::security::{ContentSecurityPolicy, SELF};

assert_eq!(ContentSecurityPolicy::new().form_action(&[SELF]).header_value(None), "form-action 'self'");

pub fn base_uri(self, sources: &[&str]) -> Self

base-uri: allowed <base href> values.

Examples

use ocre::security::{ContentSecurityPolicy, SELF};

assert_eq!(ContentSecurityPolicy::new().base_uri(&[SELF]).header_value(None), "base-uri 'self'");

pub fn upgrade_insecure_requests(self) -> Self

upgrade-insecure-requests: browsers load http: resources over HTTPS.

Examples

use ocre::security::ContentSecurityPolicy;

let csp = ContentSecurityPolicy::new().upgrade_insecure_requests();
assert_eq!(csp.header_value(None), "upgrade-insecure-requests");

pub fn report_uri(self, uri: &str) -> Self

report-uri: where browsers POST violation reports (JSON), e.g. a route of the app.

Examples

use ocre::security::ContentSecurityPolicy;

let csp = ContentSecurityPolicy::new().report_uri("/csp-reports");
assert_eq!(csp.header_value(None), "report-uri /csp-reports");

pub fn report_to(self, group: &str) -> Self

report-to: the Reporting-Endpoints group violation reports go to.

Send the Reporting-Endpoints: csp="/csp-reports" header too (browsers without Reporting API support use report_uri).

Examples

use ocre::security::ContentSecurityPolicy;

assert_eq!(ContentSecurityPolicy::new().report_to("csp").header_value(None), "report-to csp");

pub fn report_only(self) -> Self

Sends Content-Security-Policy-Report-Only: browsers report violations but block nothing.

Examples

use ocre::security::{ContentSecurityPolicy, SELF};

let csp = ContentSecurityPolicy::new().default_src(&[SELF]).report_only();
assert_eq!(csp.header_name(), "content-security-policy-report-only");

pub fn header_name(&self) -> HeaderName

content-security-policy, or content-security-policy-report-only after report_only.

Examples

assert_eq!(ocre::security::ContentSecurityPolicy::new().header_name(), "content-security-policy");

pub fn header_value(&self, nonce: Option<&str>) -> String

The header value, with NONCE replaced by 'nonce-<nonce>' (and dropped when nonce is None).

Examples

use ocre::security::{ContentSecurityPolicy, NONCE, SELF};

let csp = ContentSecurityPolicy::new().default_src(&[SELF]).script_src(&[SELF, NONCE]);
assert_eq!(csp.header_value(Some("n0nce")), "default-src 'self'; script-src 'self' 'nonce-n0nce'");
assert_eq!(csp.header_value(None), "default-src 'self'; script-src 'self'");

Trait Implementations

impl Clone for ContentSecurityPolicy

fn clone(&self) -> ContentSecurityPolicy

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for ContentSecurityPolicy

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for ContentSecurityPolicy

fn default() -> ContentSecurityPolicy

Returns the “default value” for a type.

impl Eq for ContentSecurityPolicy

impl<S> Layer<S> for ContentSecurityPolicy

type Service = PolicyService<S, ContentSecurityPolicy>

The wrapped service

fn layer(&self, inner: S) -> Self::Service

Wrap the given service with the middleware, returning a new service that has been decorated with the middleware.

impl PartialEq for ContentSecurityPolicy

fn eq(&self, other: &ContentSecurityPolicy) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl StructuralPartialEq for ContentSecurityPolicy