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, 282 insertions, 0 deletions

diff --git a/getrandom/src/lib.rs b/getrandom/src/lib.rs
new file mode 100644
index 0000000..c305406
--- /dev/null
+++ b/getrandom/src/lib.rs
@@ -0,0 +1,282 @@
+// Copyright 2019 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.
+
+//! Interface to the random number generator of the operating system.
+//!
+//! # Platform sources
+//!
+//! | OS               | interface
+//! |------------------|---------------------------------------------------------
+//! | Linux, Android   | [`getrandom`][1] system call if available, otherwise [`/dev/urandom`][2] after successfully polling `/dev/random`
+//! | Windows          | [`RtlGenRandom`][3]
+//! | macOS            | [`getentropy()`][19] if available, otherwise [`/dev/random`][20] (identical to `/dev/urandom`)
+//! | iOS              | [`SecRandomCopyBytes`][4]
+//! | FreeBSD          | [`getrandom()`][21] if available, otherwise [`kern.arandom`][5]
+//! | OpenBSD          | [`getentropy`][6]
+//! | NetBSD           | [`kern.arandom`][7]
+//! | 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         | [`cloudabi_sys_random_get`][13]
+//! | Haiku            | `/dev/random` (identical to `/dev/urandom`)
+//! | L4RE, SGX, UEFI  | [RDRAND][18]
+//! | Hermit           | [RDRAND][18] as [`sys_rand`][22] is currently broken.
+//! | VxWorks          | `randABytes` after checking entropy pool initialization with `randSecure`
+//! | Web browsers     | [`Crypto.getRandomValues`][14] (see [Support for WebAssembly and asm.js][16])
+//! | Node.js          | [`crypto.randomBytes`][15] (see [Support for WebAssembly and asm.js][16])
+//! | WASI             | [`__wasi_random_get`][17]
+//!
+//! Getrandom 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.
+//!
+//! ## Unsupported targets
+//!
+//! By default, compiling `getrandom` for an unsupported target will result in
+//! a compilation error. If you want to build an application which uses `getrandom`
+//! for such target, you can either:
+//! - Use [`[replace]`][replace] or [`[patch]`][patch] section in your `Cargo.toml`
+//! to switch to a custom implementation with a support of your target.
+//! - Enable the `dummy` feature to have getrandom use an implementation that always
+//! fails at run-time on unsupported targets.
+//!
+//! [replace]: https://doc.rust-lang.org/cargo/reference/manifest.html#the-replace-section
+//! [patch]: https://doc.rust-lang.org/cargo/reference/manifest.html#the-patch-section
+//!
+//! ## Support for WebAssembly and asm.js
+//!
+//! Getrandom supports all of Rust's current `wasm32` targets, and it works with
+//! both Node.js and web browsers. The three Emscripten targets
+//! `asmjs-unknown-emscripten`, `wasm32-unknown-emscripten`, and
+//! `wasm32-experimental-emscripten` use Emscripten's `/dev/random` emulation.
+//! The WASI target `wasm32-wasi` uses the [`__wasi_random_get`][17] function
+//! defined by the WASI standard.
+//!
+//! Getrandom also supports `wasm32-unknown-unknown` by directly calling
+//! JavaScript methods. Rust currently has two ways to do this: [bindgen] and
+//! [stdweb]. Getrandom supports using either one by enabling the
+//! `wasm-bindgen` or `stdweb` crate features. Note that if both features are
+//! enabled, `wasm-bindgen` will be used. If neither feature is enabled, calls
+//! to `getrandom` will always fail at runtime.
+//!
+//! [bindgen]: https://github.com/rust-lang/rust-bindgen
+//! [stdweb]: https://github.com/koute/stdweb
+//!
+//! ## 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; in these cases we always choose to block.
+//!
+//! On Linux (when the `getrandom` system call is not available) and on NetBSD
+//! reading from `/dev/urandom` never blocks, even when the OS hasn't collected
+//! enough entropy yet. To avoid returning low-entropy bytes, we first read from
+//! `/dev/random` and only switch to `/dev/urandom` once this has succeeded.
+//!
+//! # Error handling
+//!
+//! We always choose failure over returning insecure "random" bytes. In general,
+//! on supported platforms, failure is highly unlikely, though not impossible.
+//! If an error does occur, then it is likely that it will occur on every call to
+//! `getrandom`, hence after the first successful call one can be reasonably
+//! confident that no errors will occur.
+//!
+//! On unsupported platforms, `getrandom` always fails. See the [`Error`] type
+//! for more information on what data is returned on failure.
+//!
+//! [1]: http://man7.org/linux/man-pages/man2/getrandom.2.html
+//! [2]: http://man7.org/linux/man-pages/man4/urandom.4.html
+//! [3]: https://docs.microsoft.com/en-us/windows/desktop/api/ntsecapi/nf-ntsecapi-rtlgenrandom
+//! [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]: https://netbsd.gw.com/cgi-bin/man-cgi?sysctl+7+NetBSD-8.0
+//! [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.dev/fuchsia-src/zircon/syscalls/cprng_draw
+//! [12]: https://github.com/redox-os/randd/blob/master/src/main.rs
+//! [13]: https://github.com/nuxinl/cloudabi#random_get
+//! [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-asmjs
+//! [17]: https://github.com/WebAssembly/WASI/blob/master/design/WASI-core.md#__wasi_random_get
+//! [18]: https://software.intel.com/en-us/articles/intel-digital-random-number-generator-drng-software-implementation-guide
+//! [19]: https://www.unix.com/man-page/mojave/2/getentropy/
+//! [20]: https://www.unix.com/man-page/mojave/4/random/
+//! [21]: https://www.freebsd.org/cgi/man.cgi?query=getrandom&manpath=FreeBSD+12.0-stable
+//! [22]: https://github.com/hermitcore/libhermit-rs/blob/09c38b0371cee6f56a541400ba453e319e43db53/src/syscalls/random.rs#L21
+
+#![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/"
+)]
+#![no_std]
+#![cfg_attr(feature = "stdweb", recursion_limit = "128")]
+#![warn(rust_2018_idioms, unused_lifetimes, missing_docs)]
+
+#[macro_use]
+extern crate cfg_if;
+
+cfg_if! {
+    if #[cfg(feature = "log")] {
+        #[allow(unused)]
+        #[macro_use]
+        extern crate log;
+    } else {
+        #[allow(unused)]
+        macro_rules! error {
+            ($($x:tt)*) => {};
+        }
+        #[allow(unused)]
+        macro_rules! warn {
+            ($($x:tt)*) => {};
+        }
+        #[allow(unused)]
+        macro_rules! info {
+            ($($x:tt)*) => {};
+        }
+    }
+}
+
+mod error;
+pub use crate::error::Error;
+
+#[allow(dead_code)]
+mod util;
+
+#[cfg(target_os = "vxworks")]
+#[allow(dead_code)]
+mod util_libc;
+
+cfg_if! {
+    // Unlike the other Unix, Fuchsia and iOS don't use the libc to make any calls.
+    if #[cfg(any(target_os = "android", target_os = "dragonfly", target_os = "emscripten",
+                 target_os = "freebsd", target_os = "haiku",     target_os = "illumos",
+                 target_os = "linux",   target_os = "macos",     target_os = "netbsd",
+                 target_os = "openbsd", target_os = "redox",     target_os = "solaris"))] {
+        #[allow(dead_code)]
+        mod util_libc;
+        // Keep std-only trait definitions for backwards compatibility
+        mod error_impls;
+    } else if #[cfg(feature = "std")] {
+        mod error_impls;
+    }
+}
+
+// These targets read from a file as a fallback method.
+#[cfg(any(
+    target_os = "android",
+    target_os = "linux",
+    target_os = "macos",
+    target_os = "solaris",
+    target_os = "illumos",
+))]
+mod use_file;
+
+// System-specific implementations.
+//
+// These should all provide getrandom_inner with the same signature as getrandom.
+cfg_if! {
+    if #[cfg(target_os = "android")] {
+        #[path = "linux_android.rs"] mod imp;
+    } else if #[cfg(target_os = "cloudabi")] {
+        #[path = "cloudabi.rs"] mod imp;
+    } else if #[cfg(target_os = "dragonfly")] {
+        #[path = "use_file.rs"] mod imp;
+    } else if #[cfg(target_os = "emscripten")] {
+        #[path = "use_file.rs"] mod imp;
+    } else if #[cfg(target_os = "freebsd")] {
+        #[path = "bsd_arandom.rs"] mod imp;
+    } else if #[cfg(target_os = "fuchsia")] {
+        #[path = "fuchsia.rs"] mod imp;
+    } else if #[cfg(target_os = "haiku")] {
+        #[path = "use_file.rs"] mod imp;
+    } else if #[cfg(target_os = "illumos")] {
+        #[path = "solaris_illumos.rs"] mod imp;
+    } else if #[cfg(target_os = "ios")] {
+        #[path = "ios.rs"] mod imp;
+    } else if #[cfg(target_os = "linux")] {
+        #[path = "linux_android.rs"] mod imp;
+    } else if #[cfg(target_os = "macos")] {
+        #[path = "macos.rs"] mod imp;
+    } else if #[cfg(target_os = "netbsd")] {
+        #[path = "bsd_arandom.rs"] mod imp;
+    } else if #[cfg(target_os = "openbsd")] {
+        #[path = "openbsd.rs"] mod imp;
+    } else if #[cfg(target_os = "redox")] {
+        #[path = "use_file.rs"] mod imp;
+    } else if #[cfg(target_os = "solaris")] {
+        #[path = "solaris_illumos.rs"] mod imp;
+    } else if #[cfg(target_os = "wasi")] {
+        #[path = "wasi.rs"] mod imp;
+    } else if #[cfg(target_os = "vxworks")] {
+        #[path = "vxworks.rs"] mod imp;
+    } else if #[cfg(all(windows, getrandom_uwp))] {
+        #[path = "windows_uwp.rs"] mod imp;
+    } else if #[cfg(windows)] {
+        #[path = "windows.rs"] mod imp;
+    } else if #[cfg(all(target_arch = "x86_64", any(
+                  target_os = "hermit",
+                  target_os = "l4re",
+                  target_os = "uefi",
+                  target_env = "sgx",
+              )))] {
+        #[path = "rdrand.rs"] mod imp;
+    } else if #[cfg(all(target_arch = "wasm32", target_os = "unknown"))] {
+        cfg_if! {
+            if #[cfg(feature = "wasm-bindgen")] {
+                #[path = "wasm32_bindgen.rs"] mod imp;
+            } else if #[cfg(feature = "stdweb")] {
+                #[path = "wasm32_stdweb.rs"] mod imp;
+            } else {
+                // Always have an implementation for wasm32-unknown-unknown.
+                // See https://github.com/rust-random/getrandom/issues/87
+                #[path = "dummy.rs"] mod imp;
+            }
+        }
+    } else if #[cfg(feature = "dummy")] {
+        #[path = "dummy.rs"] mod imp;
+    } else {
+        compile_error!("\
+            target is not supported, for more information see: \
+            https://docs.rs/getrandom/#unsupported-targets\
+        ");
+    }
+}
+
+/// Fill `dest` with random bytes from the system's preferred random number
+/// source.
+///
+/// This function returns an error on any failure, including partial reads. We
+/// make no guarantees regarding the contents of `dest` on error. If `dest` is
+/// empty, `getrandom` immediately returns success, making no calls to the
+/// underlying operating system.
+///
+/// Blocking is possible, at least during early boot; see module documentation.
+///
+/// In general, `getrandom` will be fast enough for interactive usage, though
+/// significantly slower than a user-space CSPRNG; for the latter consider
+/// [`rand::thread_rng`](https://docs.rs/rand/*/rand/fn.thread_rng.html).
+pub fn getrandom(dest: &mut [u8]) -> Result<(), error::Error> {
+    if dest.is_empty() {
+        return Ok(());
+    }
+    imp::getrandom_inner(dest)
+}