Update nitrokey crate to 0.4.0

This change finally updates the version of the nitrokey crate that we
consume to 0.4.0. Along with that we update rand_core, one of its
dependencies, to 0.5.1. Further more we add cfg-if in version 0.1.10 and
getrandom in version 0.1.13, both of which are now new (non-development)
dependencies.

Import subrepo nitrokey/:nitrokey at e81057037e9b4f370b64c0a030a725bc6bdfb870
Import subrepo cfg-if/:cfg-if at 4484a6faf816ff8058088ad857b0c6bb2f4b02b2
Import subrepo getrandom/:getrandom at d661aa7e1b8cc80b47dabe3d2135b3b47d2858af
Import subrepo rand/:rand at d877ed528248b52d947e0484364a4e1ae59ca502

1 files changed, 53 insertions, 386 deletions

diff --git a/rand/rand_os/src/lib.rs b/rand/rand_os/src/lib.rs
index 67b0dfe..abfdf79 100644
--- a/rand/rand_os/src/lib.rs
+++ b/rand/rand_os/src/lib.rs
@@ -8,118 +8,8 @@
 // except according to those terms.
 
 //! Interface to the random number generator of the operating system.
-//!
-//! `OsRng` is the preferred external source of entropy for most applications.
-//! Commonly it is used to initialize a user-space RNG, which can then be used
-//! to generate random values with much less overhead than `OsRng`.
-//!
-//! You may prefer to use [`EntropyRng`] instead of `OsRng`. It is unlikely, but
-//! not entirely theoretical, for `OsRng` to fail. In such cases [`EntropyRng`]
-//! falls back on a good alternative entropy source.
-//!
-//! `OsRng::new()` is guaranteed to be very cheap (after the first successful
-//! call), and will never consume more than one file handle per process.
-//!
-//! # Usage example
-//! ```
-//! use rand_os::OsRng;
-//! use rand_os::rand_core::RngCore;
-//!
-//! let mut os_rng = OsRng::new().unwrap();
-//! let mut key = [0u8; 16];
-//! os_rng.fill_bytes(&mut key);
-//! let random_u64 = os_rng.next_u64();
-//! ```
-//!
-//! # Platform sources
-//!
-//! | OS               | interface
-//! |------------------|---------------------------------------------------------
-//! | Linux, Android   | [`getrandom`][1] system call if available, otherwise [`/dev/urandom`][2] after reading from `/dev/random` once
-//! | Windows          | [`RtlGenRandom`][3]
-//! | macOS, iOS       | [`SecRandomCopyBytes`][4]
-//! | FreeBSD          | [`kern.arandom`][5]
-//! | OpenBSD, Bitrig  | [`getentropy`][6]
-//! | NetBSD           | [`/dev/urandom`][7] after reading from `/dev/random` once
-//! | Dragonfly BSD    | [`/dev/random`][8]
-//! | Solaris, illumos | [`getrandom`][9] system call if available, otherwise [`/dev/random`][10]
-//! | Fuchsia OS       | [`cprng_draw`][11]
-//! | Redox            | [`rand:`][12]
-//! | CloudABI         | [`random_get`][13]
-//! | Haiku            | `/dev/random` (identical to `/dev/urandom`)
-//! | Web browsers     | [`Crypto.getRandomValues`][14] (see [Support for WebAssembly and ams.js][14])
-//! | Node.js          | [`crypto.randomBytes`][15] (see [Support for WebAssembly and ams.js][16])
-//!
-//! Rand doesn't have a blanket implementation for all Unix-like operating
-//! systems that reads from `/dev/urandom`. This ensures all supported operating
-//! systems are using the recommended interface and respect maximum buffer
-//! sizes.
-//!
-//! ## Support for WebAssembly and ams.js
-//!
-//! The three Emscripten targets `asmjs-unknown-emscripten`,
-//! `wasm32-unknown-emscripten` and `wasm32-experimental-emscripten` use
-//! Emscripten's emulation of `/dev/random` on web browsers and Node.js.
-//!
-//! The bare WASM target `wasm32-unknown-unknown` tries to call the javascript
-//! methods directly, using either `stdweb` or `wasm-bindgen` depending on what
-//! features are activated for this crate. Note that if both features are
-//! enabled `wasm-bindgen` will be used.
-//!
-//! ## Early boot
-//!
-//! It is possible that early in the boot process the OS hasn't had enough time
-//! yet to collect entropy to securely seed its RNG, especially on virtual
-//! machines.
-//!
-//! Some operating systems always block the thread until the RNG is securely
-//! seeded. This can take anywhere from a few seconds to more than a minute.
-//! Others make a best effort to use a seed from before the shutdown and don't
-//! document much.
-//!
-//! A few, Linux, NetBSD and Solaris, offer a choice between blocking, and
-//! getting an error. With `try_fill_bytes` we choose to get the error
-//! ([`ErrorKind::NotReady`]), while the other methods use a blocking interface.
-//!
-//! On Linux (when the `genrandom` system call is not available) and on NetBSD
-//! reading from `/dev/urandom` never blocks, even when the OS hasn't collected
-//! enough entropy yet. As a countermeasure we try to do a single read from
-//! `/dev/random` until we know the OS RNG is initialized (and store this in a
-//! global static).
-//!
-//! # Panics and error handling
-//!
-//! We cannot guarantee that `OsRng` will fail, but if it does, it will likely
-//! be either when `OsRng::new()` is first called or when data is first read.
-//! If you wish to catch errors early, then test reading of at least one byte
-//! from `OsRng` via [`try_fill_bytes`]. If this succeeds, it is extremely
-//! unlikely that any further errors will occur.
-//! 
-//! Only [`try_fill_bytes`] is able to report the cause of an error; the other
-//! [`RngCore`] methods may (depending on the error kind) retry several times,
-//! but must eventually panic if the error persists.
-//!
-//! [`EntropyRng`]: ../rand/rngs/struct.EntropyRng.html
-//! [`RngCore`]: ../rand_core/trait.RngCore.html
-//! [`try_fill_bytes`]: ../rand_core/trait.RngCore.html#method.tymethod.try_fill_bytes
-//! [`ErrorKind::NotReady`]: ../rand_core/enum.ErrorKind.html#variant.NotReady
-//!
-//! [1]: http://man7.org/linux/man-pages/man2/getrandom.2.html
-//! [2]: http://man7.org/linux/man-pages/man4/urandom.4.html
-//! [3]: https://msdn.microsoft.com/en-us/library/windows/desktop/aa387694.aspx
-//! [4]: https://developer.apple.com/documentation/security/1399291-secrandomcopybytes?language=objc
-//! [5]: https://www.freebsd.org/cgi/man.cgi?query=random&sektion=4
-//! [6]: https://man.openbsd.org/getentropy.2
-//! [7]: http://netbsd.gw.com/cgi-bin/man-cgi?random+4+NetBSD-current
-//! [8]: https://leaf.dragonflybsd.org/cgi/web-man?command=random&section=4
-//! [9]: https://docs.oracle.com/cd/E88353_01/html/E37841/getrandom-2.html
-//! [10]: https://docs.oracle.com/cd/E86824_01/html/E54777/random-7d.html
-//! [11]: https://fuchsia.googlesource.com/zircon/+/HEAD/docs/syscalls/cprng_draw.md
-//! [12]: https://github.com/redox-os/randd/blob/master/src/main.rs
-//! [13]: https://github.com/NuxiNL/cloudabi/blob/v0.20/cloudabi.txt#L1826
-//! [14]: https://www.w3.org/TR/WebCryptoAPI/#Crypto-method-getRandomValues
-//! [15]: https://nodejs.org/api/crypto.html#crypto_crypto_randombytes_size_callback
-//! [16]: #support-for-webassembly-and-amsjs
+// Note: keep this code in sync with the rand::rngs::os module!
+
 #![doc(html_logo_url = "https://www.rust-lang.org/logos/rust-logo-128x128-blk.png",
        html_favicon_url = "https://www.rust-lang.org/favicon.ico",
        html_root_url = "https://rust-random.github.io/rand/")]
@@ -127,46 +17,54 @@
 #![deny(missing_debug_implementations)]
 #![doc(test(attr(allow(unused_variables), deny(warnings))))]
 
-#![cfg_attr(feature = "stdweb", recursion_limit="128")]
-
-pub extern crate rand_core;
-#[cfg(feature = "log")]
-#[macro_use] extern crate log;
-
-// We have to do it here because we load macros
-#[cfg(all(target_arch = "wasm32", not(target_os = "emscripten"),
-          feature = "wasm-bindgen"))]
-extern crate wasm_bindgen;
-#[cfg(all(target_arch = "wasm32", not(target_os = "emscripten"),
-          not(feature = "wasm-bindgen"),
-          feature = "stdweb"))]
-#[macro_use] extern crate stdweb;
+#![no_std]  // but see getrandom crate
 
-#[cfg(target_env = "sgx")]
-extern crate rdrand;
+#![deprecated(since="0.2.2", note="OsRng is now provided by rand_core and rand")]
 
-#[cfg(not(feature = "log"))]
-#[macro_use]
-mod dummy_log;
+pub use rand_core;  // re-export
 
-use std::fmt;
+use getrandom::getrandom;
 use rand_core::{CryptoRng, RngCore, Error, impls};
 
-/// A random number generator that retrieves randomness straight from the
+/// A random number generator that retrieves randomness from from the
 /// operating system.
-#[derive(Clone)]
-pub struct OsRng(imp::OsRng);
-
-impl fmt::Debug for OsRng {
-    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-        self.0.fmt(f)
-    }
-}
+///
+/// This is a zero-sized struct. It can be freely constructed with `OsRng`.
+///
+/// The implementation is provided by the [getrandom] crate. Refer to
+/// [getrandom] documentation for details.
+///
+/// # Blocking and error handling
+///
+/// It is possible that when used during early boot the first call to `OsRng`
+/// will block until the system's RNG is initialised. It is also possible
+/// (though highly unlikely) for `OsRng` to fail on some platforms, most
+/// likely due to system mis-configuration.
+///
+/// After the first successful call, it is highly unlikely that failures or
+/// significant delays will occur (although performance should be expected to
+/// be much slower than a user-space PRNG).
+///
+/// # Usage example
+/// ```
+/// #![allow(deprecated)]
+/// use rand_os::rand_core::RngCore;
+/// use rand_os::OsRng;
+///
+/// let mut key = [0u8; 16];
+/// OsRng.fill_bytes(&mut key);
+/// let random_u64 = OsRng.next_u64();
+/// ```
+///
+/// [getrandom]: https://crates.io/crates/getrandom
+#[derive(Clone, Copy, Debug, Default)]
+pub struct OsRng;
 
 impl OsRng {
     /// Create a new `OsRng`.
+    #[deprecated(since="0.2.0", note="replace OsRng::new().unwrap() with just OsRng")]
     pub fn new() -> Result<OsRng, Error> {
-        imp::OsRng::new().map(OsRng)
+        Ok(OsRng)
     }
 }
 
@@ -182,258 +80,27 @@ impl RngCore for OsRng {
     }
 
     fn fill_bytes(&mut self, dest: &mut [u8]) {
-        use std::{time, thread};
-
-        // We cannot return Err(..), so we try to handle before panicking.
-        const MAX_RETRY_PERIOD: u32 = 10; // max 10s
-        const WAIT_DUR_MS: u32 = 100; // retry every 100ms
-        let wait_dur = time::Duration::from_millis(WAIT_DUR_MS as u64);
-        const RETRY_LIMIT: u32 = (MAX_RETRY_PERIOD * 1000) / WAIT_DUR_MS;
-        const TRANSIENT_RETRIES: u32 = 8;
-        let mut err_count = 0;
-        let mut error_logged = false;
-
-        // Maybe block until the OS RNG is initialized
-        let mut read = 0;
-        if let Ok(n) = self.0.test_initialized(dest, true) { read = n };
-        let dest = &mut dest[read..];
-
-        loop {
-            if let Err(e) = self.try_fill_bytes(dest) {
-                if err_count >= RETRY_LIMIT {
-                    error!("OsRng failed too many times; last error: {}", e);
-                    panic!("OsRng failed too many times; last error: {}", e);
-                }
-
-                if e.kind.should_wait() {
-                    if !error_logged {
-                        warn!("OsRng failed; waiting up to {}s and retrying. Error: {}",
-                                MAX_RETRY_PERIOD, e);
-                        error_logged = true;
-                    }
-                    err_count += 1;
-                    thread::sleep(wait_dur);
-                    continue;
-                } else if e.kind.should_retry() {
-                    if !error_logged {
-                        warn!("OsRng failed; retrying up to {} times. Error: {}",
-                                TRANSIENT_RETRIES, e);
-                        error_logged = true;
-                    }
-                    err_count += (RETRY_LIMIT + TRANSIENT_RETRIES - 1)
-                            / TRANSIENT_RETRIES;    // round up
-                    continue;
-                } else {
-                    error!("OsRng failed: {}", e);
-                    panic!("OsRng fatal error: {}", e);
-                }
-            }
-
-            break;
+        if let Err(e) = self.try_fill_bytes(dest) {
+            panic!("Error: {}", e);
         }
     }
 
     fn try_fill_bytes(&mut self, dest: &mut [u8]) -> Result<(), Error> {
-        // Some systems do not support reading 0 random bytes.
-        // (And why waste a system call?)
-        if dest.len() == 0 { return Ok(()); }
-
-        let read = self.0.test_initialized(dest, false)?;
-        let dest = &mut dest[read..];
-
-        let max = self.0.max_chunk_size();
-        if dest.len() <= max {
-            trace!("OsRng: reading {} bytes via {}",
-                   dest.len(), self.0.method_str());
-        } else {
-            trace!("OsRng: reading {} bytes via {} in {} chunks of {} bytes",
-                   dest.len(), self.0.method_str(), (dest.len() + max) / max, max);
-        }
-        for slice in dest.chunks_mut(max) {
-            self.0.fill_chunk(slice)?;
-        }
+        getrandom(dest)?;
         Ok(())
     }
 }
 
-trait OsRngImpl where Self: Sized {
-    // Create a new `OsRng` platform interface.
-    fn new() -> Result<Self, Error>;
-
-    // Fill a chunk with random bytes.
-    fn fill_chunk(&mut self, dest: &mut [u8]) -> Result<(), Error>;
-
-    // Test whether the OS RNG is initialized. This method may not be possible
-    // to support cheaply (or at all) on all operating systems.
-    //
-    // If `blocking` is set, this will cause the OS the block execution until
-    // its RNG is initialized.
-    //
-    // Random values that are read while this are stored in `dest`, the amount
-    // of read bytes is returned.
-    fn test_initialized(&mut self, _dest: &mut [u8], _blocking: bool)
-        -> Result<usize, Error> { Ok(0) }
-
-    // Maximum chunk size supported.
-    fn max_chunk_size(&self) -> usize { ::std::usize::MAX }
-
-    // Name of the OS interface (used for logging).
-    fn method_str(&self) -> &'static str;
-}
-
-#[cfg(any(target_os = "linux", target_os = "android",
-          target_os = "netbsd", target_os = "dragonfly",
-          target_os = "solaris", target_os = "redox",
-          target_os = "haiku", target_os = "emscripten"))]
-mod random_device;
-
-macro_rules! mod_use {
-    ($cond:meta, $module:ident) => {
-        #[$cond]
-        mod $module;
-        #[$cond]
-        use $module as imp;
-    }
-}
-
-mod_use!(cfg(target_os = "android"), linux_android);
-mod_use!(cfg(target_os = "bitrig"), openbsd_bitrig);
-mod_use!(cfg(target_os = "cloudabi"), cloudabi);
-mod_use!(cfg(target_os = "dragonfly"), dragonfly_haiku_emscripten);
-mod_use!(cfg(target_os = "emscripten"), dragonfly_haiku_emscripten);
-mod_use!(cfg(target_os = "freebsd"), freebsd);
-mod_use!(cfg(target_os = "fuchsia"), fuchsia);
-mod_use!(cfg(target_os = "haiku"), dragonfly_haiku_emscripten);
-mod_use!(cfg(target_os = "ios"), macos);
-mod_use!(cfg(target_os = "linux"), linux_android);
-mod_use!(cfg(target_os = "macos"), macos);
-mod_use!(cfg(target_os = "netbsd"), netbsd);
-mod_use!(cfg(target_os = "openbsd"), openbsd_bitrig);
-mod_use!(cfg(target_os = "redox"), redox);
-mod_use!(cfg(target_os = "solaris"), solaris);
-mod_use!(cfg(windows), windows);
-mod_use!(cfg(target_env = "sgx"), sgx);
-
-mod_use!(
-    cfg(all(
-        target_arch = "wasm32",
-        not(target_os = "emscripten"),
-        feature = "wasm-bindgen"
-    )),
-    wasm32_bindgen
-);
-
-mod_use!(
-    cfg(all(
-        target_arch = "wasm32",
-        not(target_os = "emscripten"),
-        not(feature = "wasm-bindgen"),
-        feature = "stdweb",
-    )),
-    wasm32_stdweb
-);
-
-/// Per #678 we use run-time failure where WASM bindings are missing
-#[cfg(all(
-    target_arch = "wasm32",
-    not(target_os = "emscripten"),
-    not(feature = "wasm-bindgen"),
-    not(feature = "stdweb"),
-))]
-mod imp {
-    use rand_core::{Error, ErrorKind};
-    use super::OsRngImpl;
-    
-    #[derive(Clone, Debug)]
-    pub struct OsRng;
-
-    impl OsRngImpl for OsRng {
-        fn new() -> Result<OsRng, Error> {
-            Err(Error::new(ErrorKind::Unavailable,
-                "OsRng: support for wasm32 requires emscripten, stdweb or wasm-bindgen"))
-        }
-
-        fn fill_chunk(&mut self, _dest: &mut [u8]) -> Result<(), Error> {
-            unimplemented!()
-        }
-
-        fn method_str(&self) -> &'static str { unimplemented!() }
-    }
+#[test]
+fn test_os_rng() {
+    let x = OsRng.next_u64();
+    let y = OsRng.next_u64();
+    assert!(x != 0);
+    assert!(x != y);
 }
 
-#[cfg(not(any(
-    target_os = "android",
-    target_os = "bitrig",
-    target_os = "cloudabi",
-    target_os = "dragonfly",
-    target_os = "emscripten",
-    target_os = "freebsd",
-    target_os = "fuchsia",
-    target_os = "haiku",
-    target_os = "ios",
-    target_os = "linux",
-    target_os = "macos",
-    target_os = "netbsd",
-    target_os = "openbsd",
-    target_os = "redox",
-    target_os = "solaris",
-    windows,
-    target_arch = "wasm32",
-    target_env = "sgx"
-)))]
-compile_error!("OS RNG support is not available for this platform");
-
-// Due to rustwasm/wasm-bindgen#201 this can't be defined in the inner os
-// modules, so hack around it for now and place it at the root.
-#[cfg(all(feature = "wasm-bindgen", target_arch = "wasm32"))]
-#[doc(hidden)]
-#[allow(missing_debug_implementations)]
-pub mod __wbg_shims {
-
-    // `extern { type Foo; }` isn't supported on 1.22 syntactically, so use a
-    // macro to work around that.
-    macro_rules! rust_122_compat {
-        ($($t:tt)*) => ($($t)*)
-    }
-
-    rust_122_compat! {
-        extern crate wasm_bindgen;
-
-        pub 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]);
-        }
-    }
+#[test]
+fn test_construction() {
+    let mut rng = OsRng::default();
+    assert!(rng.next_u64() != 0);
 }