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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 09:22:09 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 09:22:09 +0000
commit43a97878ce14b72f0981164f87f2e35e14151312 (patch)
tree620249daf56c0258faa40cbdcf9cfba06de2a846 /third_party/rust/getrandom/src/js.rs
parentInitial commit. (diff)
downloadfirefox-upstream.tar.xz
firefox-upstream.zip
Adding upstream version 110.0.1.upstream/110.0.1upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'third_party/rust/getrandom/src/js.rs')
-rw-r--r--third_party/rust/getrandom/src/js.rs144
1 files changed, 144 insertions, 0 deletions
diff --git a/third_party/rust/getrandom/src/js.rs b/third_party/rust/getrandom/src/js.rs
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+// Copyright 2018 Developers of the Rand project.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// https://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or https://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+use crate::Error;
+
+extern crate std;
+use std::thread_local;
+
+use js_sys::{global, Function, Uint8Array};
+use wasm_bindgen::{prelude::wasm_bindgen, JsCast, JsValue};
+
+// Size of our temporary Uint8Array buffer used with WebCrypto methods
+// Maximum is 65536 bytes see https://developer.mozilla.org/en-US/docs/Web/API/Crypto/getRandomValues
+const WEB_CRYPTO_BUFFER_SIZE: usize = 256;
+
+enum RngSource {
+ Node(NodeCrypto),
+ Web(WebCrypto, Uint8Array),
+}
+
+// JsValues are always per-thread, so we initialize RngSource for each thread.
+// See: https://github.com/rustwasm/wasm-bindgen/pull/955
+thread_local!(
+ static RNG_SOURCE: Result<RngSource, Error> = getrandom_init();
+);
+
+pub(crate) fn getrandom_inner(dest: &mut [u8]) -> Result<(), Error> {
+ RNG_SOURCE.with(|result| {
+ let source = result.as_ref().map_err(|&e| e)?;
+
+ match source {
+ RngSource::Node(n) => {
+ if n.random_fill_sync(dest).is_err() {
+ return Err(Error::NODE_RANDOM_FILL_SYNC);
+ }
+ }
+ RngSource::Web(crypto, buf) => {
+ // getRandomValues does not work with all types of WASM memory,
+ // so we initially write to browser memory to avoid exceptions.
+ for chunk in dest.chunks_mut(WEB_CRYPTO_BUFFER_SIZE) {
+ // The chunk can be smaller than buf's length, so we call to
+ // JS to create a smaller view of buf without allocation.
+ let sub_buf = buf.subarray(0, chunk.len() as u32);
+
+ if crypto.get_random_values(&sub_buf).is_err() {
+ return Err(Error::WEB_GET_RANDOM_VALUES);
+ }
+ sub_buf.copy_to(chunk);
+ }
+ }
+ };
+ Ok(())
+ })
+}
+
+fn getrandom_init() -> Result<RngSource, Error> {
+ let global: Global = global().unchecked_into();
+
+ // Get the Web Crypto interface if we are in a browser, Web Worker, Deno,
+ // or another environment that supports the Web Cryptography API. This
+ // also allows for user-provided polyfills in unsupported environments.
+ let crypto = match global.crypto() {
+ // Standard Web Crypto interface
+ c if c.is_object() => c,
+ // Node.js CommonJS Crypto module
+ _ if is_node(&global) => {
+ // If module.require isn't a valid function, we are in an ES module.
+ match Module::require_fn().and_then(JsCast::dyn_into::<Function>) {
+ Ok(require_fn) => match require_fn.call1(&global, &JsValue::from_str("crypto")) {
+ Ok(n) => return Ok(RngSource::Node(n.unchecked_into())),
+ Err(_) => return Err(Error::NODE_CRYPTO),
+ },
+ Err(_) => return Err(Error::NODE_ES_MODULE),
+ }
+ }
+ // IE 11 Workaround
+ _ => match global.ms_crypto() {
+ c if c.is_object() => c,
+ _ => return Err(Error::WEB_CRYPTO),
+ },
+ };
+
+ let buf = Uint8Array::new_with_length(WEB_CRYPTO_BUFFER_SIZE as u32);
+ Ok(RngSource::Web(crypto, buf))
+}
+
+// Taken from https://www.npmjs.com/package/browser-or-node
+fn is_node(global: &Global) -> bool {
+ let process = global.process();
+ if process.is_object() {
+ let versions = process.versions();
+ if versions.is_object() {
+ return versions.node().is_string();
+ }
+ }
+ false
+}
+
+#[wasm_bindgen]
+extern "C" {
+ // Return type of js_sys::global()
+ type Global;
+
+ // Web Crypto API: Crypto interface (https://www.w3.org/TR/WebCryptoAPI/)
+ type WebCrypto;
+ // Getters for the WebCrypto API
+ #[wasm_bindgen(method, getter)]
+ fn crypto(this: &Global) -> WebCrypto;
+ #[wasm_bindgen(method, getter, js_name = msCrypto)]
+ fn ms_crypto(this: &Global) -> WebCrypto;
+ // Crypto.getRandomValues()
+ #[wasm_bindgen(method, js_name = getRandomValues, catch)]
+ fn get_random_values(this: &WebCrypto, buf: &Uint8Array) -> Result<(), JsValue>;
+
+ // Node JS crypto module (https://nodejs.org/api/crypto.html)
+ type NodeCrypto;
+ // crypto.randomFillSync()
+ #[wasm_bindgen(method, js_name = randomFillSync, catch)]
+ fn random_fill_sync(this: &NodeCrypto, buf: &mut [u8]) -> Result<(), JsValue>;
+
+ // Ideally, we would just use `fn require(s: &str)` here. However, doing
+ // this causes a Webpack warning. So we instead return the function itself
+ // and manually invoke it using call1. This also lets us to check that the
+ // function actually exists, allowing for better error messages. See:
+ // https://github.com/rust-random/getrandom/issues/224
+ // https://github.com/rust-random/getrandom/issues/256
+ type Module;
+ #[wasm_bindgen(getter, static_method_of = Module, js_class = module, js_name = require, catch)]
+ fn require_fn() -> Result<JsValue, JsValue>;
+
+ // Node JS process Object (https://nodejs.org/api/process.html)
+ #[wasm_bindgen(method, getter)]
+ fn process(this: &Global) -> Process;
+ type Process;
+ #[wasm_bindgen(method, getter)]
+ fn versions(this: &Process) -> Versions;
+ type Versions;
+ #[wasm_bindgen(method, getter)]
+ fn node(this: &Versions) -> JsValue;
+}