Adding upstream version 1.64.0+dfsg1.upstream/1.64.0+dfsg1

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

13 files changed, 1853 insertions, 0 deletions

diff --git a/vendor/rand_core-0.5.1/.cargo-checksum.json b/vendor/rand_core-0.5.1/.cargo-checksum.json
new file mode 100644
index 000000000..3c6c0c61b
--- /dev/null
+++ b/vendor/rand_core-0.5.1/.cargo-checksum.json
@@ -0,0 +1 @@
+{"files":{"CHANGELOG.md":"fe41510a0892dd4d79433ea093279d093de4b37601f672b480c06f8aaaf9f595","COPYRIGHT":"90eb64f0279b0d9432accfa6023ff803bc4965212383697eee27a0f426d5f8d5","Cargo.toml":"8f401d04ac2812f3861364f3eccc7a325a64e27beada85bf6f0beb0bad97534c","LICENSE-APACHE":"aaff376532ea30a0cd5330b9502ad4a4c8bf769c539c87ffe78819d188a18ebf","LICENSE-MIT":"209fbbe0ad52d9235e37badf9cadfe4dbdc87203179c0899e738b39ade42177b","README.md":"f39238c96e33b8a2d3545add73646fe7cd3d98c00f8524ef91b3ac31488e8d83","src/block.rs":"827e03e9b050175f1a9531323e203e576660a2582ac84490291a6e27e3d32412","src/error.rs":"bb7214f4db0ecdc66db711e688413e25b00ce4f5b583c516fe981063c16b26a6","src/impls.rs":"be460c286057857dd9dd7d925f36f98bea8ca336ef4663c1b06cfed7bb94a248","src/le.rs":"cb187f58f7514877918f7f47633397e08e20392dcf072bc245d62c9e5238198c","src/lib.rs":"225b6aa8ad2a0f5afeb6bc36226641c0dd2700d2686a7052c324537aec6d64f6","src/os.rs":"142db4cef4ceb3eb0232911f7472822d4aa824545e89f374b6714d7e09c6771a"},"package":"90bde5296fc891b0cef12a6d03ddccc162ce7b2aff54160af9338f8d40df6d19"}
\ No newline at end of file
diff --git a/vendor/rand_core-0.5.1/CHANGELOG.md b/vendor/rand_core-0.5.1/CHANGELOG.md
new file mode 100644
index 000000000..dfdd6928e
--- /dev/null
+++ b/vendor/rand_core-0.5.1/CHANGELOG.md
@@ -0,0 +1,58 @@
+# Changelog
+All notable changes to this project will be documented in this file.
+
+The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/)
+and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
+
+## [0.5.1] - 2019-08-28
+- `OsRng` added to `rand_core` (#863)
+- `Error::INTERNAL_START` and `Error::CUSTOM_START` constants (#864)
+- `Error::raw_os_error` method (#864)
+- `Debug` and `Display` formatting for `getrandom` error codes without `std` (#864)
+### Changed
+- `alloc` feature in `no_std` is available since Rust 1.36 (#856)
+- Added `#[inline]` to `Error` conversion methods (#864)
+
+## [0.5.0] - 2019-06-06
+### Changed
+- Enable testing with Miri and fix incorrect pointer usages (#779, #780, #781, #783, #784)
+- Rewrite `Error` type and adjust API (#800)
+- Adjust usage of `#[inline]` for `BlockRng` and `BlockRng64`
+
+## [0.4.0] - 2019-01-24
+### Changed
+- Disable the `std` feature by default (#702)
+
+## [0.3.0] - 2018-09-24
+### Added
+- Add `SeedableRng::seed_from_u64` for convenient seeding. (#537)
+
+## [0.2.1] - 2018-06-08
+### Added
+- References to a `CryptoRng` now also implement `CryptoRng`. (#470)
+
+## [0.2.0] - 2018-05-21
+### Changed
+- Enable the `std` feature by default. (#409)
+- Remove `BlockRng{64}::inner` and `BlockRng::inner_mut`; instead making `core` public
+- Change `BlockRngCore::Results` bound to also require `AsMut<[Self::Item]>`. (#419)
+### Added
+- Add `BlockRng{64}::index` and `BlockRng{64}::generate_and_set`. (#374, #419)
+- Implement `std::io::Read` for RngCore. (#434)
+
+## [0.1.0] - 2018-04-17
+(Split out of the Rand crate, changes here are relative to rand 0.4.2.)
+### Added
+- `RngCore` and `SeedableRng` are now part of `rand_core`. (#288)
+- Add modules to help implementing RNGs `impl` and `le`. (#209, #228)
+- Add `Error` and `ErrorKind`. (#225)
+- Add `CryptoRng` marker trait. (#273)
+- Add `BlockRngCore` trait. (#281)
+- Add `BlockRng` and `BlockRng64` wrappers to help implementations. (#281, #325)
+- Add `RngCore::try_fill_bytes`. (#225)
+### Changed
+- Revise the `SeedableRng` trait. (#233)
+- Remove default implementations for `RngCore::next_u64` and `RngCore::fill_bytes`. (#288)
+
+## [0.0.1] - 2017-09-14 (yanked)
+Experimental version as part of the rand crate refactor.
diff --git a/vendor/rand_core-0.5.1/COPYRIGHT b/vendor/rand_core-0.5.1/COPYRIGHT
new file mode 100644
index 000000000..468d907ca
--- /dev/null
+++ b/vendor/rand_core-0.5.1/COPYRIGHT
@@ -0,0 +1,12 @@
+Copyrights in the Rand project are retained by their contributors. No
+copyright assignment is required to contribute to the Rand project.
+
+For full authorship information, see the version control history.
+
+Except as otherwise noted (below and/or in individual files), Rand is
+licensed under the Apache License, Version 2.0 <LICENSE-APACHE> or
+<http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+<LICENSE-MIT> or <http://opensource.org/licenses/MIT>, at your option.
+
+The Rand project includes code from the Rust project
+published under these same licenses.
diff --git a/vendor/rand_core-0.5.1/Cargo.toml b/vendor/rand_core-0.5.1/Cargo.toml
new file mode 100644
index 000000000..572276e5f
--- /dev/null
+++ b/vendor/rand_core-0.5.1/Cargo.toml
@@ -0,0 +1,43 @@
+# THIS FILE IS AUTOMATICALLY GENERATED BY CARGO
+#
+# When uploading crates to the registry Cargo will automatically
+# "normalize" Cargo.toml files for maximal compatibility
+# with all versions of Cargo and also rewrite `path` dependencies
+# to registry (e.g., crates.io) dependencies
+#
+# If you believe there's an error in this file please file an
+# issue against the rust-lang/cargo repository. If you're
+# editing this file be aware that the upstream Cargo.toml
+# will likely look very different (and much more reasonable)
+
+[package]
+edition = "2018"
+name = "rand_core"
+version = "0.5.1"
+authors = ["The Rand Project Developers", "The Rust Project Developers"]
+description = "Core random number generator traits and tools for implementation.\n"
+homepage = "https://crates.io/crates/rand_core"
+documentation = "https://rust-random.github.io/rand/rand_core/"
+readme = "README.md"
+keywords = ["random", "rng"]
+categories = ["algorithms", "no-std"]
+license = "MIT OR Apache-2.0"
+repository = "https://github.com/rust-random/rand"
+[dependencies.getrandom]
+version = "0.1"
+optional = true
+
+[dependencies.serde]
+version = "1"
+features = ["derive"]
+optional = true
+
+[features]
+alloc = []
+serde1 = ["serde"]
+std = ["alloc", "getrandom", "getrandom/std"]
+[badges.appveyor]
+repository = "rust-random/rand"
+
+[badges.travis-ci]
+repository = "rust-random/rand"
diff --git a/vendor/rand_core-0.5.1/LICENSE-APACHE b/vendor/rand_core-0.5.1/LICENSE-APACHE
new file mode 100644
index 000000000..17d74680f
--- /dev/null
+++ b/vendor/rand_core-0.5.1/LICENSE-APACHE
@@ -0,0 +1,201 @@
+                              Apache License
+                        Version 2.0, January 2004
+                     https://www.apache.org/licenses/
+
+TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+1. Definitions.
+
+   "License" shall mean the terms and conditions for use, reproduction,
+   and distribution as defined by Sections 1 through 9 of this document.
+
+   "Licensor" shall mean the copyright owner or entity authorized by
+   the copyright owner that is granting the License.
+
+   "Legal Entity" shall mean the union of the acting entity and all
+   other entities that control, are controlled by, or are under common
+   control with that entity. For the purposes of this definition,
+   "control" means (i) the power, direct or indirect, to cause the
+   direction or management of such entity, whether by contract or
+   otherwise, or (ii) ownership of fifty percent (50%) or more of the
+   outstanding shares, or (iii) beneficial ownership of such entity.
+
+   "You" (or "Your") shall mean an individual or Legal Entity
+   exercising permissions granted by this License.
+
+   "Source" form shall mean the preferred form for making modifications,
+   including but not limited to software source code, documentation
+   source, and configuration files.
+
+   "Object" form shall mean any form resulting from mechanical
+   transformation or translation of a Source form, including but
+   not limited to compiled object code, generated documentation,
+   and conversions to other media types.
+
+   "Work" shall mean the work of authorship, whether in Source or
+   Object form, made available under the License, as indicated by a
+   copyright notice that is included in or attached to the work
+   (an example is provided in the Appendix below).
+
+   "Derivative Works" shall mean any work, whether in Source or Object
+   form, that is based on (or derived from) the Work and for which the
+   editorial revisions, annotations, elaborations, or other modifications
+   represent, as a whole, an original work of authorship. For the purposes
+   of this License, Derivative Works shall not include works that remain
+   separable from, or merely link (or bind by name) to the interfaces of,
+   the Work and Derivative Works thereof.
+
+   "Contribution" shall mean any work of authorship, including
+   the original version of the Work and any modifications or additions
+   to that Work or Derivative Works thereof, that is intentionally
+   submitted to Licensor for inclusion in the Work by the copyright owner
+   or by an individual or Legal Entity authorized to submit on behalf of
+   the copyright owner. For the purposes of this definition, "submitted"
+   means any form of electronic, verbal, or written communication sent
+   to the Licensor or its representatives, including but not limited to
+   communication on electronic mailing lists, source code control systems,
+   and issue tracking systems that are managed by, or on behalf of, the
+   Licensor for the purpose of discussing and improving the Work, but
+   excluding communication that is conspicuously marked or otherwise
+   designated in writing by the copyright owner as "Not a Contribution."
+
+   "Contributor" shall mean Licensor and any individual or Legal Entity
+   on behalf of whom a Contribution has been received by Licensor and
+   subsequently incorporated within the Work.
+
+2. Grant of Copyright License. Subject to the terms and conditions of
+   this License, each Contributor hereby grants to You a perpetual,
+   worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+   copyright license to reproduce, prepare Derivative Works of,
+   publicly display, publicly perform, sublicense, and distribute the
+   Work and such Derivative Works in Source or Object form.
+
+3. Grant of Patent License. Subject to the terms and conditions of
+   this License, each Contributor hereby grants to You a perpetual,
+   worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+   (except as stated in this section) patent license to make, have made,
+   use, offer to sell, sell, import, and otherwise transfer the Work,
+   where such license applies only to those patent claims licensable
+   by such Contributor that are necessarily infringed by their
+   Contribution(s) alone or by combination of their Contribution(s)
+   with the Work to which such Contribution(s) was submitted. If You
+   institute patent litigation against any entity (including a
+   cross-claim or counterclaim in a lawsuit) alleging that the Work
+   or a Contribution incorporated within the Work constitutes direct
+   or contributory patent infringement, then any patent licenses
+   granted to You under this License for that Work shall terminate
+   as of the date such litigation is filed.
+
+4. Redistribution. You may reproduce and distribute copies of the
+   Work or Derivative Works thereof in any medium, with or without
+   modifications, and in Source or Object form, provided that You
+   meet the following conditions:
+
+   (a) You must give any other recipients of the Work or
+       Derivative Works a copy of this License; and
+
+   (b) You must cause any modified files to carry prominent notices
+       stating that You changed the files; and
+
+   (c) You must retain, in the Source form of any Derivative Works
+       that You distribute, all copyright, patent, trademark, and
+       attribution notices from the Source form of the Work,
+       excluding those notices that do not pertain to any part of
+       the Derivative Works; and
+
+   (d) If the Work includes a "NOTICE" text file as part of its
+       distribution, then any Derivative Works that You distribute must
+       include a readable copy of the attribution notices contained
+       within such NOTICE file, excluding those notices that do not
+       pertain to any part of the Derivative Works, in at least one
+       of the following places: within a NOTICE text file distributed
+       as part of the Derivative Works; within the Source form or
+       documentation, if provided along with the Derivative Works; or,
+       within a display generated by the Derivative Works, if and
+       wherever such third-party notices normally appear. The contents
+       of the NOTICE file are for informational purposes only and
+       do not modify the License. You may add Your own attribution
+       notices within Derivative Works that You distribute, alongside
+       or as an addendum to the NOTICE text from the Work, provided
+       that such additional attribution notices cannot be construed
+       as modifying the License.
+
+   You may add Your own copyright statement to Your modifications and
+   may provide additional or different license terms and conditions
+   for use, reproduction, or distribution of Your modifications, or
+   for any such Derivative Works as a whole, provided Your use,
+   reproduction, and distribution of the Work otherwise complies with
+   the conditions stated in this License.
+
+5. Submission of Contributions. Unless You explicitly state otherwise,
+   any Contribution intentionally submitted for inclusion in the Work
+   by You to the Licensor shall be under the terms and conditions of
+   this License, without any additional terms or conditions.
+   Notwithstanding the above, nothing herein shall supersede or modify
+   the terms of any separate license agreement you may have executed
+   with Licensor regarding such Contributions.
+
+6. Trademarks. This License does not grant permission to use the trade
+   names, trademarks, service marks, or product names of the Licensor,
+   except as required for reasonable and customary use in describing the
+   origin of the Work and reproducing the content of the NOTICE file.
+
+7. Disclaimer of Warranty. Unless required by applicable law or
+   agreed to in writing, Licensor provides the Work (and each
+   Contributor provides its Contributions) on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+   implied, including, without limitation, any warranties or conditions
+   of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A
+   PARTICULAR PURPOSE. You are solely responsible for determining the
+   appropriateness of using or redistributing the Work and assume any
+   risks associated with Your exercise of permissions under this License.
+
+8. Limitation of Liability. In no event and under no legal theory,
+   whether in tort (including negligence), contract, or otherwise,
+   unless required by applicable law (such as deliberate and grossly
+   negligent acts) or agreed to in writing, shall any Contributor be
+   liable to You for damages, including any direct, indirect, special,
+   incidental, or consequential damages of any character arising as a
+   result of this License or out of the use or inability to use the
+   Work (including but not limited to damages for loss of goodwill,
+   work stoppage, computer failure or malfunction, or any and all
+   other commercial damages or losses), even if such Contributor
+   has been advised of the possibility of such damages.
+
+9. Accepting Warranty or Additional Liability. While redistributing
+   the Work or Derivative Works thereof, You may choose to offer,
+   and charge a fee for, acceptance of support, warranty, indemnity,
+   or other liability obligations and/or rights consistent with this
+   License. However, in accepting such obligations, You may act only
+   on Your own behalf and on Your sole responsibility, not on behalf
+   of any other Contributor, and only if You agree to indemnify,
+   defend, and hold each Contributor harmless for any liability
+   incurred by, or claims asserted against, such Contributor by reason
+   of your accepting any such warranty or additional liability.
+
+END OF TERMS AND CONDITIONS
+
+APPENDIX: How to apply the Apache License to your work.
+
+   To apply the Apache License to your work, attach the following
+   boilerplate notice, with the fields enclosed by brackets "[]"
+   replaced with your own identifying information. (Don't include
+   the brackets!)  The text should be enclosed in the appropriate
+   comment syntax for the file format. We also recommend that a
+   file or class name and description of purpose be included on the
+   same "printed page" as the copyright notice for easier
+   identification within third-party archives.
+
+Copyright [yyyy] [name of copyright owner]
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+	https://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
diff --git a/vendor/rand_core-0.5.1/LICENSE-MIT b/vendor/rand_core-0.5.1/LICENSE-MIT
new file mode 100644
index 000000000..d93b5baf3
--- /dev/null
+++ b/vendor/rand_core-0.5.1/LICENSE-MIT
@@ -0,0 +1,26 @@
+Copyright 2018 Developers of the Rand project
+Copyright (c) 2014 The Rust Project Developers
+
+Permission is hereby granted, free of charge, to any
+person obtaining a copy of this software and associated
+documentation files (the "Software"), to deal in the
+Software without restriction, including without
+limitation the rights to use, copy, modify, merge,
+publish, distribute, sublicense, and/or sell copies of
+the Software, and to permit persons to whom the Software
+is furnished to do so, subject to the following
+conditions:
+
+The above copyright notice and this permission notice
+shall be included in all copies or substantial portions
+of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF
+ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED
+TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
+PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT
+SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
+CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR
+IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+DEALINGS IN THE SOFTWARE.
diff --git a/vendor/rand_core-0.5.1/README.md b/vendor/rand_core-0.5.1/README.md
new file mode 100644
index 000000000..467e66f98
--- /dev/null
+++ b/vendor/rand_core-0.5.1/README.md
@@ -0,0 +1,82 @@
+# rand_core
+
+[![Build Status](https://travis-ci.org/rust-random/rand.svg)](https://travis-ci.org/rust-random/rand)
+[![Build Status](https://ci.appveyor.com/api/projects/status/github/rust-random/rand?svg=true)](https://ci.appveyor.com/project/rust-random/rand)
+[![Latest version](https://img.shields.io/crates/v/rand_core.svg)](https://crates.io/crates/rand_core)
+[![Book](https://img.shields.io/badge/book-master-yellow.svg)](https://rust-random.github.io/book/)
+[![API](https://img.shields.io/badge/api-master-yellow.svg)](https://rust-random.github.io/rand/rand_core)
+[![API](https://docs.rs/rand_core/badge.svg)](https://docs.rs/rand_core)
+[![Minimum rustc version](https://img.shields.io/badge/rustc-1.32+-lightgray.svg)](https://github.com/rust-random/rand#rust-version-requirements)
+
+Core traits and error types of the [rand] library, plus tools for implementing
+RNGs.
+
+This crate is intended for use when implementing the core trait, `RngCore`; it
+defines the core traits to be implemented as well as several small functions to
+aid in their implementation and types required for error handling.
+
+The main [rand] crate re-exports most items defined in this crate, along with
+tools to convert the integer samples generated by `RngCore` to many different
+applications (including sampling from restricted ranges, conversion to floating
+point, list permutations and secure initialisation of RNGs). Most users should
+prefer to use the main [rand] crate.
+
+Links:
+
+-   [API documentation (master)](https://rust-random.github.io/rand/rand_core)
+-   [API documentation (docs.rs)](https://docs.rs/rand_core)
+-   [Changelog](https://github.com/rust-random/rand/blob/master/rand_core/CHANGELOG.md)
+
+[rand]: https://crates.io/crates/rand
+
+
+## Functionality
+
+The `rand_core` crate provides:
+
+-   base random number generator traits
+-   error-reporting types
+-   functionality to aid implementation of RNGs
+
+The traits and error types are also available via `rand`.
+
+## Versions
+
+The current version is:
+```
+rand_core = "0.5.0"
+```
+
+Rand libs have inter-dependencies and make use of the
+[semver trick](https://github.com/dtolnay/semver-trick/) in order to make traits
+compatible across crate versions. (This is especially important for `RngCore`
+and `SeedableRng`.) A few crate releases are thus compatibility shims,
+depending on the *next* lib version (e.g. `rand_core` versions `0.2.2` and
+`0.3.1`). This means, for example, that `rand_core_0_4_0::SeedableRng` and
+`rand_core_0_3_0::SeedableRng` are distinct, incompatible traits, which can
+cause build errors. Usually, running `cargo update` is enough to fix any issues.
+
+## Crate Features
+
+`rand_core` supports `no_std` and `alloc`-only configurations, as well as full
+`std` functionality. The differences between `no_std` and full `std` are small,
+comprising `RngCore` support for `Box<R>` types where `R: RngCore`,
+`std::io::Read` support for types supporting `RngCore`, and
+extensions to the `Error` type's functionality.
+
+The `std` feature is *not enabled by default*. This is primarily to avoid build
+problems where one crate implicitly requires `rand_core` with `std` support and
+another crate requires `rand` *without* `std` support. However, the `rand` crate
+continues to enable `std` support by default, both for itself and `rand_core`.
+
+The `serde1` feature can be used to derive `Serialize` and `Deserialize` for RNG
+implementations that use the `BlockRng` or `BlockRng64` wrappers.
+
+
+# License
+
+`rand_core` is distributed under the terms of both the MIT license and the
+Apache License (Version 2.0).
+
+See [LICENSE-APACHE](LICENSE-APACHE) and [LICENSE-MIT](LICENSE-MIT), and
+[COPYRIGHT](COPYRIGHT) for details.
diff --git a/vendor/rand_core-0.5.1/src/block.rs b/vendor/rand_core-0.5.1/src/block.rs
new file mode 100644
index 000000000..0ab745837
--- /dev/null
+++ b/vendor/rand_core-0.5.1/src/block.rs
@@ -0,0 +1,437 @@
+// 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.
+
+//! The `BlockRngCore` trait and implementation helpers
+//!
+//! The [`BlockRngCore`] trait exists to assist in the implementation of RNGs
+//! which generate a block of data in a cache instead of returning generated
+//! values directly.
+//!
+//! Usage of this trait is optional, but provides two advantages:
+//! implementations only need to concern themselves with generation of the
+//! block, not the various [`RngCore`] methods (especially [`fill_bytes`], where
+//! the optimal implementations are not trivial), and this allows
+//! `ReseedingRng` (see [`rand`](https://docs.rs/rand) crate) perform periodic
+//! reseeding with very low overhead.
+//!
+//! # Example
+//!
+//! ```norun
+//! use rand_core::block::{BlockRngCore, BlockRng};
+//!
+//! struct MyRngCore;
+//!
+//! impl BlockRngCore for MyRngCore {
+//!     type Results = [u32; 16];
+//!
+//!     fn generate(&mut self, results: &mut Self::Results) {
+//!         unimplemented!()
+//!     }
+//! }
+//!
+//! impl SeedableRng for MyRngCore {
+//!     type Seed = unimplemented!();
+//!     fn from_seed(seed: Self::Seed) -> Self {
+//!         unimplemented!()
+//!     }
+//! }
+//!
+//! // optionally, also implement CryptoRng for MyRngCore
+//!
+//! // Final RNG.
+//! type MyRng = BlockRng<u32, MyRngCore>;
+//! ```
+//!
+//! [`BlockRngCore`]: crate::block::BlockRngCore
+//! [`fill_bytes`]: RngCore::fill_bytes
+
+use core::convert::AsRef;
+use core::{fmt, ptr};
+#[cfg(feature="serde1")] use serde::{Serialize, Deserialize};
+use crate::{RngCore, CryptoRng, SeedableRng, Error};
+use crate::impls::{fill_via_u32_chunks, fill_via_u64_chunks};
+
+/// A trait for RNGs which do not generate random numbers individually, but in
+/// blocks (typically `[u32; N]`). This technique is commonly used by
+/// cryptographic RNGs to improve performance.
+///
+/// See the [module][crate::block] documentation for details.
+pub trait BlockRngCore {
+    /// Results element type, e.g. `u32`.
+    type Item;
+
+    /// Results type. This is the 'block' an RNG implementing `BlockRngCore`
+    /// generates, which will usually be an array like `[u32; 16]`.
+    type Results: AsRef<[Self::Item]> + AsMut<[Self::Item]> + Default;
+
+    /// Generate a new block of results.
+    fn generate(&mut self, results: &mut Self::Results);
+}
+
+
+/// A wrapper type implementing [`RngCore`] for some type implementing
+/// [`BlockRngCore`] with `u32` array buffer; i.e. this can be used to implement
+/// a full RNG from just a `generate` function.
+///
+/// The `core` field may be accessed directly but the results buffer may not.
+/// PRNG implementations can simply use a type alias
+/// (`pub type MyRng = BlockRng<MyRngCore>;`) but might prefer to use a
+/// wrapper type (`pub struct MyRng(BlockRng<MyRngCore>);`); the latter must
+/// re-implement `RngCore` but hides the implementation details and allows
+/// extra functionality to be defined on the RNG
+/// (e.g. `impl MyRng { fn set_stream(...){...} }`).
+///
+/// `BlockRng` has heavily optimized implementations of the [`RngCore`] methods
+/// reading values from the results buffer, as well as
+/// calling [`BlockRngCore::generate`] directly on the output array when
+/// [`fill_bytes`] / [`try_fill_bytes`] is called on a large array. These methods
+/// also handle the bookkeeping of when to generate a new batch of values.
+///
+/// No whole generated `u32` values are thown away and all values are consumed
+/// in-order. [`next_u32`] simply takes the next available `u32` value.
+/// [`next_u64`] is implemented by combining two `u32` values, least
+/// significant first. [`fill_bytes`] and [`try_fill_bytes`] consume a whole
+/// number of `u32` values, converting each `u32` to a byte slice in
+/// little-endian order. If the requested byte length is not a multiple of 4,
+/// some bytes will be discarded.
+///
+/// See also [`BlockRng64`] which uses `u64` array buffers. Currently there is
+/// no direct support for other buffer types.
+///
+/// For easy initialization `BlockRng` also implements [`SeedableRng`].
+///
+/// [`next_u32`]: RngCore::next_u32
+/// [`next_u64`]: RngCore::next_u64
+/// [`fill_bytes`]: RngCore::fill_bytes
+/// [`try_fill_bytes`]: RngCore::try_fill_bytes
+#[derive(Clone)]
+#[cfg_attr(feature="serde1", derive(Serialize, Deserialize))]
+pub struct BlockRng<R: BlockRngCore + ?Sized> {
+    results: R::Results,
+    index: usize,
+    /// The *core* part of the RNG, implementing the `generate` function.
+    pub core: R,
+}
+
+// Custom Debug implementation that does not expose the contents of `results`.
+impl<R: BlockRngCore + fmt::Debug> fmt::Debug for BlockRng<R> {
+    fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
+        fmt.debug_struct("BlockRng")
+           .field("core", &self.core)
+           .field("result_len", &self.results.as_ref().len())
+           .field("index", &self.index)
+           .finish()
+    }
+}
+
+impl<R: BlockRngCore> BlockRng<R> {
+    /// Create a new `BlockRng` from an existing RNG implementing
+    /// `BlockRngCore`. Results will be generated on first use.
+    #[inline]
+    pub fn new(core: R) -> BlockRng<R>{
+        let results_empty = R::Results::default();
+        BlockRng {
+            core,
+            index: results_empty.as_ref().len(),
+            results: results_empty,
+        }
+    }
+
+    /// Get the index into the result buffer.
+    ///
+    /// If this is equal to or larger than the size of the result buffer then
+    /// the buffer is "empty" and `generate()` must be called to produce new
+    /// results.
+    #[inline(always)]
+    pub fn index(&self) -> usize {
+        self.index
+    }
+
+    /// Reset the number of available results.
+    /// This will force a new set of results to be generated on next use.
+    #[inline]
+    pub fn reset(&mut self) {
+        self.index = self.results.as_ref().len();
+    }
+
+    /// Generate a new set of results immediately, setting the index to the
+    /// given value.
+    #[inline]
+    pub fn generate_and_set(&mut self, index: usize) {
+        assert!(index < self.results.as_ref().len());
+        self.core.generate(&mut self.results);
+        self.index = index;
+    }
+}
+
+impl<R: BlockRngCore<Item=u32>> RngCore for BlockRng<R>
+where <R as BlockRngCore>::Results: AsRef<[u32]> + AsMut<[u32]>
+{
+    #[inline]
+    fn next_u32(&mut self) -> u32 {
+        if self.index >= self.results.as_ref().len() {
+            self.generate_and_set(0);
+        }
+
+        let value = self.results.as_ref()[self.index];
+        self.index += 1;
+        value
+    }
+
+    #[inline]
+    fn next_u64(&mut self) -> u64 {
+        let read_u64 = |results: &[u32], index| {
+            if cfg!(any(target_endian = "little")) {
+                // requires little-endian CPU
+                #[allow(clippy::cast_ptr_alignment)]  // false positive
+                let ptr: *const u64 = results[index..=index+1].as_ptr() as *const u64;
+                unsafe { ptr::read_unaligned(ptr) }
+            } else {
+                let x = u64::from(results[index]);
+                let y = u64::from(results[index + 1]);
+                (y << 32) | x
+            }
+        };
+
+        let len = self.results.as_ref().len();
+
+        let index = self.index;
+        if index < len-1 {
+            self.index += 2;
+            // Read an u64 from the current index
+            read_u64(self.results.as_ref(), index)
+        } else if index >= len {
+            self.generate_and_set(2);
+            read_u64(self.results.as_ref(), 0)
+        } else {
+            let x = u64::from(self.results.as_ref()[len-1]);
+            self.generate_and_set(1);
+            let y = u64::from(self.results.as_ref()[0]);
+            (y << 32) | x
+        }
+    }
+
+    #[inline]
+    fn fill_bytes(&mut self, dest: &mut [u8]) {
+        let mut read_len = 0;
+        while read_len < dest.len() {
+            if self.index >= self.results.as_ref().len() {
+                self.generate_and_set(0);
+            }
+            let (consumed_u32, filled_u8) =
+                fill_via_u32_chunks(&self.results.as_ref()[self.index..],
+                                    &mut dest[read_len..]);
+
+            self.index += consumed_u32;
+            read_len += filled_u8;
+        }
+    }
+
+    #[inline(always)]
+    fn try_fill_bytes(&mut self, dest: &mut [u8]) -> Result<(), Error> {
+        self.fill_bytes(dest);
+        Ok(())
+    }
+}
+
+impl<R: BlockRngCore + SeedableRng> SeedableRng for BlockRng<R> {
+    type Seed = R::Seed;
+
+    #[inline(always)]
+    fn from_seed(seed: Self::Seed) -> Self {
+        Self::new(R::from_seed(seed))
+    }
+
+    #[inline(always)]
+    fn seed_from_u64(seed: u64) -> Self {
+        Self::new(R::seed_from_u64(seed))
+    }
+
+    #[inline(always)]
+    fn from_rng<S: RngCore>(rng: S) -> Result<Self, Error> {
+        Ok(Self::new(R::from_rng(rng)?))
+    }
+}
+
+
+
+/// A wrapper type implementing [`RngCore`] for some type implementing
+/// [`BlockRngCore`] with `u64` array buffer; i.e. this can be used to implement
+/// a full RNG from just a `generate` function.
+///
+/// This is similar to [`BlockRng`], but specialized for algorithms that operate
+/// on `u64` values.
+///
+/// No whole generated `u64` values are thrown away and all values are consumed
+/// in-order. [`next_u64`] simply takes the next available `u64` value.
+/// [`next_u32`] is however a bit special: half of a `u64` is consumed, leaving
+/// the other half in the buffer. If the next function called is [`next_u32`]
+/// then the other half is then consumed, however both [`next_u64`] and
+/// [`fill_bytes`] discard the rest of any half-consumed `u64`s when called.
+///
+/// [`fill_bytes`] and [`try_fill_bytes`] consume a whole number of `u64`
+/// values. If the requested length is not a multiple of 8, some bytes will be
+/// discarded.
+///
+/// [`next_u32`]: RngCore::next_u32
+/// [`next_u64`]: RngCore::next_u64
+/// [`fill_bytes`]: RngCore::fill_bytes
+/// [`try_fill_bytes`]: RngCore::try_fill_bytes
+#[derive(Clone)]
+#[cfg_attr(feature="serde1", derive(Serialize, Deserialize))]
+pub struct BlockRng64<R: BlockRngCore + ?Sized> {
+    results: R::Results,
+    index: usize,
+    half_used: bool, // true if only half of the previous result is used
+    /// The *core* part of the RNG, implementing the `generate` function.
+    pub core: R,
+}
+
+// Custom Debug implementation that does not expose the contents of `results`.
+impl<R: BlockRngCore + fmt::Debug> fmt::Debug for BlockRng64<R> {
+    fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
+        fmt.debug_struct("BlockRng64")
+           .field("core", &self.core)
+           .field("result_len", &self.results.as_ref().len())
+           .field("index", &self.index)
+           .field("half_used", &self.half_used)
+           .finish()
+    }
+}
+
+impl<R: BlockRngCore> BlockRng64<R> {
+    /// Create a new `BlockRng` from an existing RNG implementing
+    /// `BlockRngCore`. Results will be generated on first use.
+    #[inline]
+    pub fn new(core: R) -> BlockRng64<R>{
+        let results_empty = R::Results::default();
+        BlockRng64 {
+            core,
+            index: results_empty.as_ref().len(),
+            half_used: false,
+            results: results_empty,
+        }
+    }
+
+    /// Get the index into the result buffer.
+    ///
+    /// If this is equal to or larger than the size of the result buffer then
+    /// the buffer is "empty" and `generate()` must be called to produce new
+    /// results.
+    #[inline(always)]
+    pub fn index(&self) -> usize {
+        self.index
+    }
+
+    /// Reset the number of available results.
+    /// This will force a new set of results to be generated on next use.
+    #[inline]
+    pub fn reset(&mut self) {
+        self.index = self.results.as_ref().len();
+        self.half_used = false;
+    }
+
+    /// Generate a new set of results immediately, setting the index to the
+    /// given value.
+    #[inline]
+    pub fn generate_and_set(&mut self, index: usize) {
+        assert!(index < self.results.as_ref().len());
+        self.core.generate(&mut self.results);
+        self.index = index;
+        self.half_used = false;
+    }
+}
+
+impl<R: BlockRngCore<Item=u64>> RngCore for BlockRng64<R>
+where <R as BlockRngCore>::Results: AsRef<[u64]> + AsMut<[u64]>
+{
+    #[inline]
+    fn next_u32(&mut self) -> u32 {
+        let mut index = self.index * 2 - self.half_used as usize;
+        if index >= self.results.as_ref().len() * 2 {
+            self.core.generate(&mut self.results);
+            self.index = 0;
+            // `self.half_used` is by definition `false`
+            self.half_used = false;
+            index = 0;
+        }
+
+        self.half_used = !self.half_used;
+        self.index += self.half_used as usize;
+
+        // Index as if this is a u32 slice.
+        unsafe {
+            let results =
+                &*(self.results.as_ref() as *const [u64] as *const [u32]);
+            if cfg!(target_endian = "little") {
+                *results.get_unchecked(index)
+            } else {
+                *results.get_unchecked(index ^ 1)
+            }
+        }
+    }
+
+    #[inline]
+    fn next_u64(&mut self) -> u64 {
+        if self.index >= self.results.as_ref().len() {
+            self.core.generate(&mut self.results);
+            self.index = 0;
+        }
+
+        let value = self.results.as_ref()[self.index];
+        self.index += 1;
+        self.half_used = false;
+        value
+    }
+
+    #[inline]
+    fn fill_bytes(&mut self, dest: &mut [u8]) {
+        let mut read_len = 0;
+        self.half_used = false;
+        while read_len < dest.len() {
+            if self.index as usize >= self.results.as_ref().len() {
+                self.core.generate(&mut self.results);
+                self.index = 0;
+            }
+
+            let (consumed_u64, filled_u8) =
+                fill_via_u64_chunks(&self.results.as_ref()[self.index as usize..],
+                                    &mut dest[read_len..]);
+
+            self.index += consumed_u64;
+            read_len += filled_u8;
+        }
+    }
+
+    #[inline(always)]
+    fn try_fill_bytes(&mut self, dest: &mut [u8]) -> Result<(), Error> {
+        self.fill_bytes(dest);
+        Ok(())
+    }
+}
+
+impl<R: BlockRngCore + SeedableRng> SeedableRng for BlockRng64<R> {
+    type Seed = R::Seed;
+
+    #[inline(always)]
+    fn from_seed(seed: Self::Seed) -> Self {
+        Self::new(R::from_seed(seed))
+    }
+
+    #[inline(always)]
+    fn seed_from_u64(seed: u64) -> Self {
+        Self::new(R::seed_from_u64(seed))
+    }
+
+    #[inline(always)]
+    fn from_rng<S: RngCore>(rng: S) -> Result<Self, Error> {
+        Ok(Self::new(R::from_rng(rng)?))
+    }
+}
+
+impl<R: BlockRngCore + CryptoRng> CryptoRng for BlockRng<R> {}
diff --git a/vendor/rand_core-0.5.1/src/error.rs b/vendor/rand_core-0.5.1/src/error.rs
new file mode 100644
index 000000000..30b095c3c
--- /dev/null
+++ b/vendor/rand_core-0.5.1/src/error.rs
@@ -0,0 +1,190 @@
+// 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.
+
+//! Error types
+
+use core::fmt;
+use core::num::NonZeroU32;
+
+
+/// Error type of random number generators
+///
+/// In order to be compatible with `std` and `no_std`, this type has two
+/// possible implementations: with `std` a boxed `Error` trait object is stored,
+/// while with `no_std` we merely store an error code.
+pub struct Error {
+    #[cfg(feature="std")]
+    inner: Box<dyn std::error::Error + Send + Sync + 'static>,
+    #[cfg(not(feature="std"))]
+    code: NonZeroU32,
+}
+
+impl Error {
+    /// Construct from any type supporting `std::error::Error`
+    /// 
+    /// Available only when configured with `std`.
+    /// 
+    /// See also `From<NonZeroU32>`, which is available with and without `std`.
+    #[cfg(feature="std")]
+    #[inline]
+    pub fn new<E>(err: E) -> Self
+    where E: Into<Box<dyn std::error::Error + Send + Sync + 'static>>
+    {
+        Error { inner: err.into() }
+    }
+    
+    /// Reference the inner error (`std` only)
+    /// 
+    /// When configured with `std`, this is a trivial operation and never
+    /// panics. Without `std`, this method is simply unavailable.
+    #[cfg(feature="std")]
+    #[inline]
+    pub fn inner(&self) -> &(dyn std::error::Error + Send + Sync + 'static) {
+        &*self.inner
+    }
+    
+    /// Unwrap the inner error (`std` only)
+    /// 
+    /// When configured with `std`, this is a trivial operation and never
+    /// panics. Without `std`, this method is simply unavailable.
+    #[cfg(feature="std")]
+    #[inline]
+    pub fn take_inner(self) -> Box<dyn std::error::Error + Send + Sync + 'static> {
+        self.inner
+    }
+    
+    /// Codes below this point represent OS Errors (i.e. positive i32 values).
+    /// Codes at or above this point, but below [`Error::CUSTOM_START`] are
+    /// reserved for use by the `rand` and `getrandom` crates.
+    pub const INTERNAL_START: u32 = 1 << 31;
+
+    /// Codes at or above this point can be used by users to define their own
+    /// custom errors.
+    pub const CUSTOM_START: u32 = (1 << 31) + (1 << 30);
+
+    /// Extract the raw OS error code (if this error came from the OS)
+    ///
+    /// This method is identical to `std::io::Error::raw_os_error()`, except
+    /// that it works in `no_std` contexts. If this method returns `None`, the
+    /// error value can still be formatted via the `Diplay` implementation.
+    #[inline]
+    pub fn raw_os_error(&self) -> Option<i32> {
+        #[cfg(feature="std")] {
+            if let Some(e) = self.inner.downcast_ref::<std::io::Error>() {
+                return e.raw_os_error();
+            }
+        }
+        match self.code() {
+            Some(code) if u32::from(code) < Self::INTERNAL_START =>
+                Some(u32::from(code) as i32),
+            _ => None,
+        }
+    }
+
+    /// Retrieve the error code, if any.
+    /// 
+    /// If this `Error` was constructed via `From<NonZeroU32>`, then this method
+    /// will return this `NonZeroU32` code (for `no_std` this is always the
+    /// case). Otherwise, this method will return `None`.
+    #[inline]
+    pub fn code(&self) -> Option<NonZeroU32> {
+        #[cfg(feature="std")] {
+            self.inner.downcast_ref::<ErrorCode>().map(|c| c.0)
+        }
+        #[cfg(not(feature="std"))] {
+            Some(self.code)
+        }
+    }
+}
+
+impl fmt::Debug for Error {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        #[cfg(feature="std")] {
+            write!(f, "Error {{ inner: {:?} }}", self.inner)
+        }
+        #[cfg(all(feature="getrandom", not(feature="std")))] {
+            getrandom::Error::from(self.code).fmt(f)
+        }
+        #[cfg(not(feature="getrandom"))] {
+            write!(f, "Error {{ code: {} }}", self.code)
+        }
+    }
+}
+
+impl fmt::Display for Error {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        #[cfg(feature="std")] {
+            write!(f, "{}", self.inner)
+        }
+        #[cfg(all(feature="getrandom", not(feature="std")))] {
+            getrandom::Error::from(self.code).fmt(f)
+        }
+        #[cfg(not(feature="getrandom"))] {
+            write!(f, "error code {}", self.code)
+        }
+    }
+}
+
+impl From<NonZeroU32> for Error {
+    #[inline]
+    fn from(code: NonZeroU32) -> Self {
+        #[cfg(feature="std")] {
+            Error { inner: Box::new(ErrorCode(code)) }
+        }
+        #[cfg(not(feature="std"))] {
+            Error { code }
+        }
+    }
+}
+
+#[cfg(feature="getrandom")]
+impl From<getrandom::Error> for Error {
+    #[inline]
+    fn from(error: getrandom::Error) -> Self {
+        #[cfg(feature="std")] {
+            Error { inner: Box::new(error) }
+        }
+        #[cfg(not(feature="std"))] {
+            Error { code: error.code() }
+        }
+    }
+}
+
+#[cfg(feature="std")]
+impl std::error::Error for Error {
+    #[inline]
+    fn source(&self) -> Option<&(dyn std::error::Error + 'static)> {
+        self.inner.source()
+    }
+}
+
+#[cfg(feature="std")]
+impl From<Error> for std::io::Error {
+    #[inline]
+    fn from(error: Error) -> Self {
+        if let Some(code) = error.raw_os_error() {
+            std::io::Error::from_raw_os_error(code)
+        } else {
+            std::io::Error::new(std::io::ErrorKind::Other, error)
+        }
+    }
+}
+
+#[cfg(feature="std")]
+#[derive(Debug, Copy, Clone)]
+struct ErrorCode(NonZeroU32);
+
+#[cfg(feature="std")]
+impl fmt::Display for ErrorCode {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        write!(f, "error code {}", self.0)
+    }
+}
+
+#[cfg(feature="std")]
+impl std::error::Error for ErrorCode {}
diff --git a/vendor/rand_core-0.5.1/src/impls.rs b/vendor/rand_core-0.5.1/src/impls.rs
new file mode 100644
index 000000000..dee4ed11e
--- /dev/null
+++ b/vendor/rand_core-0.5.1/src/impls.rs
@@ -0,0 +1,158 @@
+// 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.
+
+//! Helper functions for implementing `RngCore` functions.
+//!
+//! For cross-platform reproducibility, these functions all use Little Endian:
+//! least-significant part first. For example, `next_u64_via_u32` takes `u32`
+//! values `x, y`, then outputs `(y << 32) | x`. To implement `next_u32`
+//! from `next_u64` in little-endian order, one should use `next_u64() as u32`.
+//!
+//! Byte-swapping (like the std `to_le` functions) is only needed to convert
+//! to/from byte sequences, and since its purpose is reproducibility,
+//! non-reproducible sources (e.g. `OsRng`) need not bother with it.
+
+use core::ptr::copy_nonoverlapping;
+use core::slice;
+use core::cmp::min;
+use core::mem::size_of;
+use crate::RngCore;
+
+
+/// Implement `next_u64` via `next_u32`, little-endian order.
+pub fn next_u64_via_u32<R: RngCore + ?Sized>(rng: &mut R) -> u64 {
+    // Use LE; we explicitly generate one value before the next.
+    let x = u64::from(rng.next_u32());
+    let y = u64::from(rng.next_u32());
+    (y << 32) | x
+}
+
+/// Implement `fill_bytes` via `next_u64` and `next_u32`, little-endian order.
+///
+/// The fastest way to fill a slice is usually to work as long as possible with
+/// integers. That is why this method mostly uses `next_u64`, and only when
+/// there are 4 or less bytes remaining at the end of the slice it uses
+/// `next_u32` once.
+pub fn fill_bytes_via_next<R: RngCore + ?Sized>(rng: &mut R, dest: &mut [u8]) {
+    let mut left = dest;
+    while left.len() >= 8 {
+        let (l, r) = {left}.split_at_mut(8);
+        left = r;
+        let chunk: [u8; 8] = rng.next_u64().to_le_bytes();
+        l.copy_from_slice(&chunk);
+    }
+    let n = left.len();
+    if n > 4 {
+        let chunk: [u8; 8] = rng.next_u64().to_le_bytes();
+        left.copy_from_slice(&chunk[..n]);
+    } else if n > 0 {
+        let chunk: [u8; 4] = rng.next_u32().to_le_bytes();
+        left.copy_from_slice(&chunk[..n]);
+    }
+}
+
+macro_rules! impl_uint_from_fill {
+    ($rng:expr, $ty:ty, $N:expr) => ({
+        debug_assert!($N == size_of::<$ty>());
+
+        let mut int: $ty = 0;
+        unsafe {
+            let ptr = &mut int as *mut $ty as *mut u8;
+            let slice = slice::from_raw_parts_mut(ptr, $N);
+            $rng.fill_bytes(slice);
+        }
+        int
+    });
+}
+
+macro_rules! fill_via_chunks {
+    ($src:expr, $dst:expr, $ty:ty, $size:expr) => ({
+        let chunk_size_u8 = min($src.len() * $size, $dst.len());
+        let chunk_size = (chunk_size_u8 + $size - 1) / $size;
+        if cfg!(target_endian="little") {
+            unsafe {
+                copy_nonoverlapping(
+                    $src.as_ptr() as *const u8,
+                    $dst.as_mut_ptr(),
+                    chunk_size_u8);
+            }
+        } else {
+            for (&n, chunk) in $src.iter().zip($dst.chunks_mut($size)) {
+                let tmp = n.to_le();
+                let src_ptr = &tmp as *const $ty as *const u8;
+                unsafe {
+                    copy_nonoverlapping(src_ptr,
+                                        chunk.as_mut_ptr(),
+                                        chunk.len());
+                }
+            }
+        }
+
+        (chunk_size, chunk_size_u8)
+    });
+}
+
+/// Implement `fill_bytes` by reading chunks from the output buffer of a block
+/// based RNG.
+///
+/// The return values are `(consumed_u32, filled_u8)`.
+///
+/// `filled_u8` is the number of filled bytes in `dest`, which may be less than
+/// the length of `dest`.
+/// `consumed_u32` is the number of words consumed from `src`, which is the same
+/// as `filled_u8 / 4` rounded up.
+///
+/// # Example
+/// (from `IsaacRng`)
+///
+/// ```ignore
+/// fn fill_bytes(&mut self, dest: &mut [u8]) {
+///     let mut read_len = 0;
+///     while read_len < dest.len() {
+///         if self.index >= self.rsl.len() {
+///             self.isaac();
+///         }
+///
+///         let (consumed_u32, filled_u8) =
+///             impls::fill_via_u32_chunks(&mut self.rsl[self.index..],
+///                                        &mut dest[read_len..]);
+///
+///         self.index += consumed_u32;
+///         read_len += filled_u8;
+///     }
+/// }
+/// ```
+pub fn fill_via_u32_chunks(src: &[u32], dest: &mut [u8]) -> (usize, usize) {
+    fill_via_chunks!(src, dest, u32, 4)
+}
+
+/// Implement `fill_bytes` by reading chunks from the output buffer of a block
+/// based RNG.
+///
+/// The return values are `(consumed_u64, filled_u8)`.
+/// `filled_u8` is the number of filled bytes in `dest`, which may be less than
+/// the length of `dest`.
+/// `consumed_u64` is the number of words consumed from `src`, which is the same
+/// as `filled_u8 / 8` rounded up.
+///
+/// See `fill_via_u32_chunks` for an example.
+pub fn fill_via_u64_chunks(src: &[u64], dest: &mut [u8]) -> (usize, usize) {
+    fill_via_chunks!(src, dest, u64, 8)
+}
+
+/// Implement `next_u32` via `fill_bytes`, little-endian order.
+pub fn next_u32_via_fill<R: RngCore + ?Sized>(rng: &mut R) -> u32 {
+    impl_uint_from_fill!(rng, u32, 4)
+}
+
+/// Implement `next_u64` via `fill_bytes`, little-endian order.
+pub fn next_u64_via_fill<R: RngCore + ?Sized>(rng: &mut R) -> u64 {
+    impl_uint_from_fill!(rng, u64, 8)
+}
+
+// TODO: implement tests for the above
diff --git a/vendor/rand_core-0.5.1/src/le.rs b/vendor/rand_core-0.5.1/src/le.rs
new file mode 100644
index 000000000..266651f10
--- /dev/null
+++ b/vendor/rand_core-0.5.1/src/le.rs
@@ -0,0 +1,68 @@
+// 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.
+
+//! Little-Endian utilities
+//! 
+//! Little-Endian order has been chosen for internal usage; this makes some
+//! useful functions available.
+
+use core::ptr;
+
+macro_rules! read_slice {
+    ($src:expr, $dst:expr, $size:expr, $which:ident) => {{
+        assert_eq!($src.len(), $size * $dst.len());
+
+        unsafe {
+            ptr::copy_nonoverlapping(
+                $src.as_ptr(),
+                $dst.as_mut_ptr() as *mut u8,
+                $src.len());
+        }
+        for v in $dst.iter_mut() {
+            *v = v.$which();
+        }
+    }};
+}
+
+/// Reads unsigned 32 bit integers from `src` into `dst`.
+/// Borrowed from the `byteorder` crate.
+#[inline]
+pub fn read_u32_into(src: &[u8], dst: &mut [u32]) {
+    read_slice!(src, dst, 4, to_le);
+}
+
+/// Reads unsigned 64 bit integers from `src` into `dst`.
+/// Borrowed from the `byteorder` crate.
+#[inline]
+pub fn read_u64_into(src: &[u8], dst: &mut [u64]) {
+    read_slice!(src, dst, 8, to_le);
+}
+
+#[test]
+fn test_read() {
+    let bytes = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16];
+    
+    let mut buf = [0u32; 4];
+    read_u32_into(&bytes, &mut buf);
+    assert_eq!(buf[0], 0x04030201);
+    assert_eq!(buf[3], 0x100F0E0D);
+    
+    let mut buf = [0u32; 3];
+    read_u32_into(&bytes[1..13], &mut buf);  // unaligned
+    assert_eq!(buf[0], 0x05040302);
+    assert_eq!(buf[2], 0x0D0C0B0A);
+    
+    let mut buf = [0u64; 2];
+    read_u64_into(&bytes, &mut buf);
+    assert_eq!(buf[0], 0x0807060504030201);
+    assert_eq!(buf[1], 0x100F0E0D0C0B0A09);
+    
+    let mut buf = [0u64; 1];
+    read_u64_into(&bytes[7..15], &mut buf); // unaligned
+    assert_eq!(buf[0], 0x0F0E0D0C0B0A0908);
+}
diff --git a/vendor/rand_core-0.5.1/src/lib.rs b/vendor/rand_core-0.5.1/src/lib.rs
new file mode 100644
index 000000000..d8e0189f2
--- /dev/null
+++ b/vendor/rand_core-0.5.1/src/lib.rs
@@ -0,0 +1,492 @@
+// Copyright 2018 Developers of the Rand project.
+// Copyright 2017-2018 The Rust Project Developers.
+//
+// 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.
+
+//! Random number generation traits
+//!
+//! This crate is mainly of interest to crates publishing implementations of
+//! [`RngCore`]. Other users are encouraged to use the [`rand`] crate instead
+//! which re-exports the main traits and error types.
+//!
+//! [`RngCore`] is the core trait implemented by algorithmic pseudo-random number
+//! generators and external random-number sources.
+//!
+//! [`SeedableRng`] is an extension trait for construction from fixed seeds and
+//! other random number generators.
+//!
+//! [`Error`] is provided for error-handling. It is safe to use in `no_std`
+//! environments.
+//!
+//! The [`impls`] and [`le`] sub-modules include a few small functions to assist
+//! implementation of [`RngCore`].
+//!
+//! [`rand`]: https://docs.rs/rand
+
+#![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/")]
+
+#![deny(missing_docs)]
+#![deny(missing_debug_implementations)]
+#![doc(test(attr(allow(unused_variables), deny(warnings))))]
+
+#![allow(clippy::unreadable_literal)]
+
+#![cfg_attr(not(feature="std"), no_std)]
+
+
+use core::default::Default;
+use core::convert::AsMut;
+use core::ptr::copy_nonoverlapping;
+
+#[cfg(all(feature="alloc", not(feature="std")))] extern crate alloc;
+#[cfg(all(feature="alloc", not(feature="std")))] use alloc::boxed::Box;
+
+pub use error::Error;
+#[cfg(feature="getrandom")] pub use os::OsRng;
+
+
+mod error;
+pub mod block;
+pub mod impls;
+pub mod le;
+#[cfg(feature="getrandom")] mod os;
+
+
+/// The core of a random number generator.
+///
+/// This trait encapsulates the low-level functionality common to all
+/// generators, and is the "back end", to be implemented by generators.
+/// End users should normally use the `Rng` trait from the [`rand`] crate,
+/// which is automatically implemented for every type implementing `RngCore`.
+///
+/// Three different methods for generating random data are provided since the
+/// optimal implementation of each is dependent on the type of generator. There
+/// is no required relationship between the output of each; e.g. many
+/// implementations of [`fill_bytes`] consume a whole number of `u32` or `u64`
+/// values and drop any remaining unused bytes.
+///
+/// The [`try_fill_bytes`] method is a variant of [`fill_bytes`] allowing error
+/// handling; it is not deemed sufficiently useful to add equivalents for
+/// [`next_u32`] or [`next_u64`] since the latter methods are almost always used
+/// with algorithmic generators (PRNGs), which are normally infallible.
+///
+/// Algorithmic generators implementing [`SeedableRng`] should normally have
+/// *portable, reproducible* output, i.e. fix Endianness when converting values
+/// to avoid platform differences, and avoid making any changes which affect
+/// output (except by communicating that the release has breaking changes).
+///
+/// Typically implementators will implement only one of the methods available
+/// in this trait directly, then use the helper functions from the
+/// [`impls`] module to implement the other methods.
+///
+/// It is recommended that implementations also implement:
+///
+/// - `Debug` with a custom implementation which *does not* print any internal
+///   state (at least, [`CryptoRng`]s should not risk leaking state through
+///   `Debug`).
+/// - `Serialize` and `Deserialize` (from Serde), preferably making Serde
+///   support optional at the crate level in PRNG libs.
+/// - `Clone`, if possible.
+/// - *never* implement `Copy` (accidental copies may cause repeated values).
+/// - *do not* implement `Default` for pseudorandom generators, but instead
+///   implement [`SeedableRng`], to guide users towards proper seeding.
+///   External / hardware RNGs can choose to implement `Default`.
+/// - `Eq` and `PartialEq` could be implemented, but are probably not useful.
+///
+/// # Example
+///
+/// A simple example, obviously not generating very *random* output:
+///
+/// ```
+/// #![allow(dead_code)]
+/// use rand_core::{RngCore, Error, impls};
+///
+/// struct CountingRng(u64);
+///
+/// impl RngCore for CountingRng {
+///     fn next_u32(&mut self) -> u32 {
+///         self.next_u64() as u32
+///     }
+///
+///     fn next_u64(&mut self) -> u64 {
+///         self.0 += 1;
+///         self.0
+///     }
+///
+///     fn fill_bytes(&mut self, dest: &mut [u8]) {
+///         impls::fill_bytes_via_next(self, dest)
+///     }
+///
+///     fn try_fill_bytes(&mut self, dest: &mut [u8]) -> Result<(), Error> {
+///         Ok(self.fill_bytes(dest))
+///     }
+/// }
+/// ```
+///
+/// [`rand`]: https://docs.rs/rand
+/// [`try_fill_bytes`]: RngCore::try_fill_bytes
+/// [`fill_bytes`]: RngCore::fill_bytes
+/// [`next_u32`]: RngCore::next_u32
+/// [`next_u64`]: RngCore::next_u64
+pub trait RngCore {
+    /// Return the next random `u32`.
+    ///
+    /// RNGs must implement at least one method from this trait directly. In
+    /// the case this method is not implemented directly, it can be implemented
+    /// using `self.next_u64() as u32` or via
+    /// [`fill_bytes`](impls::next_u32_via_fill).
+    fn next_u32(&mut self) -> u32;
+
+    /// Return the next random `u64`.
+    ///
+    /// RNGs must implement at least one method from this trait directly. In
+    /// the case this method is not implemented directly, it can be implemented
+    /// via [`next_u32`](impls::next_u64_via_u32) or via
+    /// [`fill_bytes`](impls::next_u64_via_fill).
+    fn next_u64(&mut self) -> u64;
+
+    /// Fill `dest` with random data.
+    ///
+    /// RNGs must implement at least one method from this trait directly. In
+    /// the case this method is not implemented directly, it can be implemented
+    /// via [`next_u*`](impls::fill_bytes_via_next) or
+    /// via [`try_fill_bytes`](RngCore::try_fill_bytes); if this generator can
+    /// fail the implementation must choose how best to handle errors here
+    /// (e.g. panic with a descriptive message or log a warning and retry a few
+    /// times).
+    ///
+    /// This method should guarantee that `dest` is entirely filled
+    /// with new data, and may panic if this is impossible
+    /// (e.g. reading past the end of a file that is being used as the
+    /// source of randomness).
+    fn fill_bytes(&mut self, dest: &mut [u8]);
+
+    /// Fill `dest` entirely with random data.
+    ///
+    /// This is the only method which allows an RNG to report errors while
+    /// generating random data thus making this the primary method implemented
+    /// by external (true) RNGs (e.g. `OsRng`) which can fail. It may be used
+    /// directly to generate keys and to seed (infallible) PRNGs.
+    ///
+    /// Other than error handling, this method is identical to [`fill_bytes`];
+    /// thus this may be implemented using `Ok(self.fill_bytes(dest))` or
+    /// `fill_bytes` may be implemented with
+    /// `self.try_fill_bytes(dest).unwrap()` or more specific error handling.
+    ///
+    /// [`fill_bytes`]: RngCore::fill_bytes
+    fn try_fill_bytes(&mut self, dest: &mut [u8]) -> Result<(), Error>;
+}
+
+/// A marker trait used to indicate that an [`RngCore`] or [`BlockRngCore`]
+/// implementation is supposed to be cryptographically secure.
+///
+/// *Cryptographically secure generators*, also known as *CSPRNGs*, should
+/// satisfy an additional properties over other generators: given the first
+/// *k* bits of an algorithm's output
+/// sequence, it should not be possible using polynomial-time algorithms to
+/// predict the next bit with probability significantly greater than 50%.
+///
+/// Some generators may satisfy an additional property, however this is not
+/// required by this trait: if the CSPRNG's state is revealed, it should not be
+/// computationally-feasible to reconstruct output prior to this. Some other
+/// generators allow backwards-computation and are consided *reversible*.
+///
+/// Note that this trait is provided for guidance only and cannot guarantee
+/// suitability for cryptographic applications. In general it should only be
+/// implemented for well-reviewed code implementing well-regarded algorithms.
+///
+/// Note also that use of a `CryptoRng` does not protect against other
+/// weaknesses such as seeding from a weak entropy source or leaking state.
+///
+/// [`BlockRngCore`]: block::BlockRngCore
+pub trait CryptoRng {}
+
+/// A random number generator that can be explicitly seeded.
+///
+/// This trait encapsulates the low-level functionality common to all
+/// pseudo-random number generators (PRNGs, or algorithmic generators).
+///
+/// [`rand`]: https://docs.rs/rand
+pub trait SeedableRng: Sized {
+    /// Seed type, which is restricted to types mutably-dereferencable as `u8`
+    /// arrays (we recommend `[u8; N]` for some `N`).
+    ///
+    /// It is recommended to seed PRNGs with a seed of at least circa 100 bits,
+    /// which means an array of `[u8; 12]` or greater to avoid picking RNGs with
+    /// partially overlapping periods.
+    ///
+    /// For cryptographic RNG's a seed of 256 bits is recommended, `[u8; 32]`.
+    ///
+    ///
+    /// # Implementing `SeedableRng` for RNGs with large seeds
+    ///
+    /// Note that the required traits `core::default::Default` and
+    /// `core::convert::AsMut<u8>` are not implemented for large arrays
+    /// `[u8; N]` with `N` > 32. To be able to implement the traits required by
+    /// `SeedableRng` for RNGs with such large seeds, the newtype pattern can be
+    /// used:
+    ///
+    /// ```
+    /// use rand_core::SeedableRng;
+    ///
+    /// const N: usize = 64;
+    /// pub struct MyRngSeed(pub [u8; N]);
+    /// pub struct MyRng(MyRngSeed);
+    ///
+    /// impl Default for MyRngSeed {
+    ///     fn default() -> MyRngSeed {
+    ///         MyRngSeed([0; N])
+    ///     }
+    /// }
+    ///
+    /// impl AsMut<[u8]> for MyRngSeed {
+    ///     fn as_mut(&mut self) -> &mut [u8] {
+    ///         &mut self.0
+    ///     }
+    /// }
+    ///
+    /// impl SeedableRng for MyRng {
+    ///     type Seed = MyRngSeed;
+    ///
+    ///     fn from_seed(seed: MyRngSeed) -> MyRng {
+    ///         MyRng(seed)
+    ///     }
+    /// }
+    /// ```
+    type Seed: Sized + Default + AsMut<[u8]>;
+
+    /// Create a new PRNG using the given seed.
+    ///
+    /// PRNG implementations are allowed to assume that bits in the seed are
+    /// well distributed. That means usually that the number of one and zero
+    /// bits are roughly equal, and values like 0, 1 and (size - 1) are unlikely.
+    /// Note that many non-cryptographic PRNGs will show poor quality output
+    /// if this is not adhered to. If you wish to seed from simple numbers, use
+    /// `seed_from_u64` instead.
+    ///
+    /// All PRNG implementations should be reproducible unless otherwise noted:
+    /// given a fixed `seed`, the same sequence of output should be produced
+    /// on all runs, library versions and architectures (e.g. check endianness).
+    /// Any "value-breaking" changes to the generator should require bumping at
+    /// least the minor version and documentation of the change.
+    ///
+    /// It is not required that this function yield the same state as a
+    /// reference implementation of the PRNG given equivalent seed; if necessary
+    /// another constructor replicating behaviour from a reference
+    /// implementation can be added.
+    ///
+    /// PRNG implementations should make sure `from_seed` never panics. In the
+    /// case that some special values (like an all zero seed) are not viable
+    /// seeds it is preferable to map these to alternative constant value(s),
+    /// for example `0xBAD5EEDu32` or `0x0DDB1A5E5BAD5EEDu64` ("odd biases? bad
+    /// seed"). This is assuming only a small number of values must be rejected.
+    fn from_seed(seed: Self::Seed) -> Self;
+
+    /// Create a new PRNG using a `u64` seed.
+    ///
+    /// This is a convenience-wrapper around `from_seed` to allow construction
+    /// of any `SeedableRng` from a simple `u64` value. It is designed such that
+    /// low Hamming Weight numbers like 0 and 1 can be used and should still
+    /// result in good, independent seeds to the PRNG which is returned.
+    ///
+    /// This **is not suitable for cryptography**, as should be clear given that
+    /// the input size is only 64 bits.
+    ///
+    /// Implementations for PRNGs *may* provide their own implementations of
+    /// this function, but the default implementation should be good enough for
+    /// all purposes. *Changing* the implementation of this function should be
+    /// considered a value-breaking change.
+    fn seed_from_u64(mut state: u64) -> Self {
+        // We use PCG32 to generate a u32 sequence, and copy to the seed
+        const MUL: u64 = 6364136223846793005;
+        const INC: u64 = 11634580027462260723;
+
+        let mut seed = Self::Seed::default();
+        for chunk in seed.as_mut().chunks_mut(4) {
+            // We advance the state first (to get away from the input value,
+            // in case it has low Hamming Weight).
+            state = state.wrapping_mul(MUL).wrapping_add(INC);
+
+            // Use PCG output function with to_le to generate x:
+            let xorshifted = (((state >> 18) ^ state) >> 27) as u32;
+            let rot = (state >> 59) as u32;
+            let x = xorshifted.rotate_right(rot).to_le();
+
+            unsafe {
+                let p = &x as *const u32 as *const u8;
+                copy_nonoverlapping(p, chunk.as_mut_ptr(), chunk.len());
+            }
+        }
+
+        Self::from_seed(seed)
+    }
+
+    /// Create a new PRNG seeded from another `Rng`.
+    ///
+    /// This may be useful when needing to rapidly seed many PRNGs from a master
+    /// PRNG, and to allow forking of PRNGs. It may be considered deterministic.
+    ///
+    /// The master PRNG should be at least as high quality as the child PRNGs.
+    /// When seeding non-cryptographic child PRNGs, we recommend using a
+    /// different algorithm for the master PRNG (ideally a CSPRNG) to avoid
+    /// correlations between the child PRNGs. If this is not possible (e.g.
+    /// forking using small non-crypto PRNGs) ensure that your PRNG has a good
+    /// mixing function on the output or consider use of a hash function with
+    /// `from_seed`.
+    ///
+    /// Note that seeding `XorShiftRng` from another `XorShiftRng` provides an
+    /// extreme example of what can go wrong: the new PRNG will be a clone
+    /// of the parent.
+    ///
+    /// PRNG implementations are allowed to assume that a good RNG is provided
+    /// for seeding, and that it is cryptographically secure when appropriate.
+    /// As of `rand` 0.7 / `rand_core` 0.5, implementations overriding this
+    /// method should ensure the implementation satisfies reproducibility
+    /// (in prior versions this was not required).
+    ///
+    /// [`rand`]: https://docs.rs/rand
+    /// [`rand_os`]: https://docs.rs/rand_os
+    fn from_rng<R: RngCore>(mut rng: R) -> Result<Self, Error> {
+        let mut seed = Self::Seed::default();
+        rng.try_fill_bytes(seed.as_mut())?;
+        Ok(Self::from_seed(seed))
+    }
+
+    /// Creates a new instance of the RNG seeded via [`getrandom`].
+    ///
+    /// This method is the recommended way to construct non-deterministic PRNGs
+    /// since it is convenient and secure.
+    ///
+    /// In case the overhead of using [`getrandom`] to seed *many* PRNGs is an
+    /// issue, one may prefer to seed from a local PRNG, e.g.
+    /// `from_rng(thread_rng()).unwrap()`.
+    ///
+    /// # Panics
+    ///
+    /// If [`getrandom`] is unable to provide secure entropy this method will panic.
+    ///
+    /// [`getrandom`]: https://docs.rs/getrandom
+    #[cfg(feature="getrandom")]
+    fn from_entropy() -> Self {
+        let mut seed = Self::Seed::default();
+        if let Err(err) = getrandom::getrandom(seed.as_mut()) {
+            panic!("from_entropy failed: {}", err);
+        }
+        Self::from_seed(seed)
+    }
+}
+
+// Implement `RngCore` for references to an `RngCore`.
+// Force inlining all functions, so that it is up to the `RngCore`
+// implementation and the optimizer to decide on inlining.
+impl<'a, R: RngCore + ?Sized> RngCore for &'a mut R {
+    #[inline(always)]
+    fn next_u32(&mut self) -> u32 {
+        (**self).next_u32()
+    }
+
+    #[inline(always)]
+    fn next_u64(&mut self) -> u64 {
+        (**self).next_u64()
+    }
+
+    #[inline(always)]
+    fn fill_bytes(&mut self, dest: &mut [u8]) {
+        (**self).fill_bytes(dest)
+    }
+
+    #[inline(always)]
+    fn try_fill_bytes(&mut self, dest: &mut [u8]) -> Result<(), Error> {
+        (**self).try_fill_bytes(dest)
+    }
+}
+
+// Implement `RngCore` for boxed references to an `RngCore`.
+// Force inlining all functions, so that it is up to the `RngCore`
+// implementation and the optimizer to decide on inlining.
+#[cfg(feature="alloc")]
+impl<R: RngCore + ?Sized> RngCore for Box<R> {
+    #[inline(always)]
+    fn next_u32(&mut self) -> u32 {
+        (**self).next_u32()
+    }
+
+    #[inline(always)]
+    fn next_u64(&mut self) -> u64 {
+        (**self).next_u64()
+    }
+
+    #[inline(always)]
+    fn fill_bytes(&mut self, dest: &mut [u8]) {
+        (**self).fill_bytes(dest)
+    }
+
+    #[inline(always)]
+    fn try_fill_bytes(&mut self, dest: &mut [u8]) -> Result<(), Error> {
+        (**self).try_fill_bytes(dest)
+    }
+}
+
+#[cfg(feature="std")]
+impl std::io::Read for dyn RngCore {
+    fn read(&mut self, buf: &mut [u8]) -> Result<usize, std::io::Error> {
+        self.try_fill_bytes(buf)?;
+        Ok(buf.len())
+    }
+}
+
+// Implement `CryptoRng` for references to an `CryptoRng`.
+impl<'a, R: CryptoRng + ?Sized> CryptoRng for &'a mut R {}
+
+// Implement `CryptoRng` for boxed references to an `CryptoRng`.
+#[cfg(feature="alloc")]
+impl<R: CryptoRng + ?Sized> CryptoRng for Box<R> {}
+
+#[cfg(test)]
+mod test {
+    use super::*;
+
+    #[test]
+    fn test_seed_from_u64() {
+        struct SeedableNum(u64);
+        impl SeedableRng for SeedableNum {
+            type Seed = [u8; 8];
+            fn from_seed(seed: Self::Seed) -> Self {
+                let mut x = [0u64; 1];
+                le::read_u64_into(&seed, &mut x);
+                SeedableNum(x[0])
+            }
+        }
+
+        const N: usize = 8;
+        const SEEDS: [u64; N] = [0u64, 1, 2, 3, 4, 8, 16, -1i64 as u64];
+        let mut results = [0u64; N];
+        for (i, seed) in SEEDS.iter().enumerate() {
+            let SeedableNum(x) = SeedableNum::seed_from_u64(*seed);
+            results[i] = x;
+        }
+
+        for (i1, r1) in results.iter().enumerate() {
+            let weight = r1.count_ones();
+            // This is the binomial distribution B(64, 0.5), so chance of
+            // weight < 20 is binocdf(19, 64, 0.5) = 7.8e-4, and same for
+            // weight > 44.
+            assert!(weight >= 20 && weight <= 44);
+
+            for (i2, r2) in results.iter().enumerate() {
+                if i1 == i2 { continue; }
+                let diff_weight = (r1 ^ r2).count_ones();
+                assert!(diff_weight >= 20);
+            }
+        }
+
+        // value-breakage test:
+        assert_eq!(results[0], 5029875928683246316);
+    }
+}
diff --git a/vendor/rand_core-0.5.1/src/os.rs b/vendor/rand_core-0.5.1/src/os.rs
new file mode 100644
index 000000000..fc23a57d9
--- /dev/null
+++ b/vendor/rand_core-0.5.1/src/os.rs
@@ -0,0 +1,85 @@
+// 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.
+// Note: keep this code in sync with the rand_os crate!
+
+use getrandom::getrandom;
+use crate::{CryptoRng, RngCore, Error, impls};
+
+/// A random number generator that retrieves randomness from from the
+/// operating system.
+///
+/// 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.
+///
+/// This struct is only available when specifying the crate feature `getrandom`
+/// or `std`. When using the `rand` lib, it is also available as `rand::rngs::OsRng`.
+///
+/// # 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
+/// ```
+/// use rand_core::{RngCore, 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 CryptoRng for OsRng {}
+
+impl RngCore for OsRng {
+    fn next_u32(&mut self) -> u32 {
+        impls::next_u32_via_fill(self)
+    }
+
+    fn next_u64(&mut self) -> u64 {
+        impls::next_u64_via_fill(self)
+    }
+
+    fn fill_bytes(&mut self, dest: &mut [u8]) {
+        if let Err(e) = self.try_fill_bytes(dest) {
+            panic!("Error: {}", e);
+        }
+    }
+
+    fn try_fill_bytes(&mut self, dest: &mut [u8]) -> Result<(), Error> {
+        getrandom(dest)?;
+        Ok(())
+    }
+}
+
+#[test]
+fn test_os_rng() {
+    let x = OsRng.next_u64();
+    let y = OsRng.next_u64();
+    assert!(x != 0);
+    assert!(x != y);
+}
+
+#[test]
+fn test_construction() {
+    let mut rng = OsRng::default();
+    assert!(rng.next_u64() != 0);
+}