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Diffstat (limited to 'rand/rand_os/src/wasm32_bindgen.rs')
-rw-r--r-- | rand/rand_os/src/wasm32_bindgen.rs | 125 |
1 files changed, 0 insertions, 125 deletions
diff --git a/rand/rand_os/src/wasm32_bindgen.rs b/rand/rand_os/src/wasm32_bindgen.rs deleted file mode 100644 index 8e7c979..0000000 --- a/rand/rand_os/src/wasm32_bindgen.rs +++ /dev/null @@ -1,125 +0,0 @@ -// 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. - -//! Implementation for WASM via wasm-bindgen - -use rand_core::{Error, ErrorKind}; -use super::OsRngImpl; - -use wasm_bindgen::prelude::*; - -#[wasm_bindgen] -extern "C" { - pub type Function; - #[wasm_bindgen(constructor)] - pub fn new(s: &str) -> Function; - #[wasm_bindgen(method)] - pub fn call(this: &Function, self_: &JsValue) -> JsValue; - - pub type This; - #[wasm_bindgen(method, getter, structural, js_name = self)] - pub fn self_(me: &This) -> JsValue; - #[wasm_bindgen(method, getter, structural)] - pub fn crypto(me: &This) -> JsValue; - - #[derive(Clone, Debug)] - pub type BrowserCrypto; - - // TODO: these `structural` annotations here ideally wouldn't be here to - // avoid a JS shim, but for now with feature detection they're - // unavoidable. - #[wasm_bindgen(method, js_name = getRandomValues, structural, getter)] - pub fn get_random_values_fn(me: &BrowserCrypto) -> JsValue; - #[wasm_bindgen(method, js_name = getRandomValues, structural)] - pub fn get_random_values(me: &BrowserCrypto, buf: &mut [u8]); - - #[wasm_bindgen(js_name = require)] - pub fn node_require(s: &str) -> NodeCrypto; - - #[derive(Clone, Debug)] - pub type NodeCrypto; - - #[wasm_bindgen(method, js_name = randomFillSync, structural)] - pub fn random_fill_sync(me: &NodeCrypto, buf: &mut [u8]); -} - -#[derive(Clone, Debug)] -pub enum OsRng { - Node(NodeCrypto), - Browser(BrowserCrypto), -} - -impl OsRngImpl for OsRng { - fn new() -> Result<OsRng, Error> { - // First up we need to detect if we're running in node.js or a - // browser. To do this we get ahold of the `this` object (in a bit - // of a roundabout fashion). - // - // Once we have `this` we look at its `self` property, which is - // only defined on the web (either a main window or web worker). - let this = Function::new("return this").call(&JsValue::undefined()); - assert!(this != JsValue::undefined()); - let this = This::from(this); - let is_browser = this.self_() != JsValue::undefined(); - - if !is_browser { - return Ok(OsRng::Node(node_require("crypto"))) - } - - // If `self` is defined then we're in a browser somehow (main window - // or web worker). Here we want to try to use - // `crypto.getRandomValues`, but if `crypto` isn't defined we assume - // we're in an older web browser and the OS RNG isn't available. - let crypto = this.crypto(); - if crypto.is_undefined() { - let msg = "self.crypto is undefined"; - return Err(Error::new(ErrorKind::Unavailable, msg)) - } - - // Test if `crypto.getRandomValues` is undefined as well - let crypto: BrowserCrypto = crypto.into(); - if crypto.get_random_values_fn().is_undefined() { - let msg = "crypto.getRandomValues is undefined"; - return Err(Error::new(ErrorKind::Unavailable, msg)) - } - - // Ok! `self.crypto.getRandomValues` is a defined value, so let's - // assume we can do browser crypto. - Ok(OsRng::Browser(crypto)) - } - - fn fill_chunk(&mut self, dest: &mut [u8]) -> Result<(), Error> { - match *self { - OsRng::Node(ref n) => n.random_fill_sync(dest), - OsRng::Browser(ref n) => n.get_random_values(dest), - } - Ok(()) - } - - fn max_chunk_size(&self) -> usize { - match *self { - OsRng::Node(_) => usize::max_value(), - OsRng::Browser(_) => { - // see https://developer.mozilla.org/en-US/docs/Web/API/Crypto/getRandomValues - // - // where it says: - // - // > A QuotaExceededError DOMException is thrown if the - // > requested length is greater than 65536 bytes. - 65536 - } - } - } - - fn method_str(&self) -> &'static str { - match *self { - OsRng::Node(_) => "crypto.randomFillSync", - OsRng::Browser(_) => "crypto.getRandomValues", - } - } -} |