Merging upstream version 1.70.0+dfsg2.

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

8 files changed, 529 insertions, 0 deletions

diff --git a/vendor/rfc6979/.cargo-checksum.json b/vendor/rfc6979/.cargo-checksum.json
new file mode 100644
index 000000000..6343ed90f
--- /dev/null
+++ b/vendor/rfc6979/.cargo-checksum.json
@@ -0,0 +1 @@
+{"files":{"CHANGELOG.md":"f8ea1da44e3db690aeae24569faaca6a63f8a6912555316f8c0a62fdeacae113","Cargo.toml":"b4c943615d8ace03699ef2c142aeeb9da741cd70e867454b06b4a99fb351fed3","LICENSE-APACHE":"78779d420019e6b4630376af8e86b6b335ee8a2f89ede6e0411e0469a326aaa4","LICENSE-MIT":"bdebaf9156a298f8fdab56dd26cb5144673de522d80f4c0d88e0039145f147f9","README.md":"081eb58ccc4eef0e9ee2e614ee1597d9ed399b72d298096ec39a0c34f483dba3","src/lib.rs":"8efb6aadf3750b553e950222b296e287ca6820f7d0ab3f03244e1f17b0ce93c5","tests/lib.rs":"68922b3fb793f7f64a6fdf8aa59b6fb9432d4706d7ad1d82129a8337c5cf6568"},"package":"7743f17af12fa0b03b803ba12cd6a8d9483a587e89c69445e3909655c0b9fabb"}
\ No newline at end of file
diff --git a/vendor/rfc6979/CHANGELOG.md b/vendor/rfc6979/CHANGELOG.md
new file mode 100644
index 000000000..06a24c1a8
--- /dev/null
+++ b/vendor/rfc6979/CHANGELOG.md
@@ -0,0 +1,32 @@
+# Changelog
+All notable changes to this project will be documented in this file.
+
+The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
+and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
+
+## 0.3.1 (2022-11-03)
+### Added
+- Usage example ([#577])
+
+[#577]: https://github.com/RustCrypto/signatures/pull/577
+
+## 0.3.0 (2022-06-26)
+### Changed
+- Use `SimpleHmac` to implement `HmacDrbg` ([#499])
+
+[#499]: https://github.com/RustCrypto/signatures/pull/499
+
+## 0.2.0 (2022-05-08)
+### Added
+- License files ([#447])
+
+### Changed
+- Bump `hmac` dependency to v0.12 ([#433])
+- Bump `crypto-bigint` dependency to v0.4 ([#469])
+
+[#433]: https://github.com/RustCrypto/signatures/pull/433
+[#447]: https://github.com/RustCrypto/signatures/pull/447
+[#469]: https://github.com/RustCrypto/signatures/pull/469
+
+### 0.1.0 (2021-11-21)
+- Initial release
diff --git a/vendor/rfc6979/Cargo.toml b/vendor/rfc6979/Cargo.toml
new file mode 100644
index 000000000..7ff912e2f
--- /dev/null
+++ b/vendor/rfc6979/Cargo.toml
@@ -0,0 +1,60 @@
+# 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 are reading this file be aware that the original Cargo.toml
+# will likely look very different (and much more reasonable).
+# See Cargo.toml.orig for the original contents.
+
+[package]
+edition = "2021"
+rust-version = "1.57"
+name = "rfc6979"
+version = "0.3.1"
+authors = ["RustCrypto Developers"]
+description = """
+Pure Rust implementation of RFC6979: Deterministic Usage of the
+Digital Signature Algorithm (DSA) and Elliptic Curve Digital Signature Algorithm (ECDSA)
+"""
+readme = "README.md"
+keywords = [
+    "dsa",
+    "ecdsa",
+    "signature",
+]
+categories = [
+    "cryptography",
+    "no-std",
+]
+license = "Apache-2.0 OR MIT"
+repository = "https://github.com/RustCrypto/signatures/tree/master/rfc6979"
+
+[package.metadata.docs.rs]
+all-features = true
+rustdoc-args = [
+    "--cfg",
+    "docsrs",
+]
+
+[dependencies.crypto-bigint]
+version = "0.4"
+features = [
+    "generic-array",
+    "zeroize",
+]
+default-features = false
+
+[dependencies.hmac]
+version = "0.12"
+features = ["reset"]
+default-features = false
+
+[dependencies.zeroize]
+version = "1"
+default-features = false
+
+[dev-dependencies.sha2]
+version = "0.10"
diff --git a/vendor/rfc6979/LICENSE-APACHE b/vendor/rfc6979/LICENSE-APACHE
new file mode 100644
index 000000000..c394d8ad9
--- /dev/null
+++ b/vendor/rfc6979/LICENSE-APACHE
@@ -0,0 +1,201 @@
+                              Apache License
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+TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
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+6. Trademarks. This License does not grant permission to use the trade
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+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
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+Copyright 2018-2022 RustCrypto Developers
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diff --git a/vendor/rfc6979/LICENSE-MIT b/vendor/rfc6979/LICENSE-MIT
new file mode 100644
index 000000000..81a3d57ac
--- /dev/null
+++ b/vendor/rfc6979/LICENSE-MIT
@@ -0,0 +1,25 @@
+Copyright (c) 2018-2022 RustCrypto 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
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+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/rfc6979/README.md b/vendor/rfc6979/README.md
new file mode 100644
index 000000000..e19b54e83
--- /dev/null
+++ b/vendor/rfc6979/README.md
@@ -0,0 +1,55 @@
+# [RustCrypto]: RFC6979 Deterministic Signatures
+
+[![crate][crate-image]][crate-link]
+[![Docs][docs-image]][docs-link]
+[![Build Status][build-image]][build-link]
+![Apache2/MIT licensed][license-image]
+![MSRV][rustc-image]
+[![Project Chat][chat-image]][chat-link]
+
+Pure Rust implementation of RFC6979: Deterministic Usage of the
+Digital Signature Algorithm (DSA) and Elliptic Curve Digital Signature Algorithm (ECDSA).
+
+Algorithm described in RFC 6979 § 3.2:
+<https://tools.ietf.org/html/rfc6979#section-3>
+
+[Documentation][docs-link]
+
+## Minimum Supported Rust Version
+
+This crate requires **Rust 1.57** at a minimum.
+
+We may change the MSRV in the future, but it will be accompanied by a minor
+version bump.
+
+## License
+
+All crates licensed under either of
+
+ * [Apache License, Version 2.0](http://www.apache.org/licenses/LICENSE-2.0)
+ * [MIT license](http://opensource.org/licenses/MIT)
+
+at your option.
+
+### Contribution
+
+Unless you explicitly state otherwise, any contribution intentionally submitted
+for inclusion in the work by you, as defined in the Apache-2.0 license, shall be
+dual licensed as above, without any additional terms or conditions.
+
+[//]: # (badges)
+
+[crate-image]: https://buildstats.info/crate/rfc6979
+[crate-link]: https://crates.io/crates/rfc6979
+[docs-image]: https://docs.rs/rfc6979/badge.svg
+[docs-link]: https://docs.rs/rfc6979/
+[build-image]: https://github.com/RustCrypto/signatures/actions/workflows/rfc6979.yml/badge.svg
+[build-link]: https://github.com/RustCrypto/signatures/actions/workflows/rfc6979.yml
+[license-image]: https://img.shields.io/badge/license-Apache2.0/MIT-blue.svg
+[rustc-image]: https://img.shields.io/badge/rustc-1.57+-blue.svg
+[chat-image]: https://img.shields.io/badge/zulip-join_chat-blue.svg
+[chat-link]: https://rustcrypto.zulipchat.com/#narrow/stream/260048-signatures
+
+[//]: # (links)
+
+[RustCrypto]: https://github.com/RustCrypto
diff --git a/vendor/rfc6979/src/lib.rs b/vendor/rfc6979/src/lib.rs
new file mode 100644
index 000000000..32df1e652
--- /dev/null
+++ b/vendor/rfc6979/src/lib.rs
@@ -0,0 +1,141 @@
+#![doc = include_str!("../README.md")]
+
+//! ## Usage
+//!
+//! See also: the documentation for the [`generate_k`] function.
+//!
+//! ```
+//! use crypto_bigint::{ArrayEncoding, U256};
+//! use sha2::{Digest, Sha256};
+//!
+//! // NIST P-256 field modulus
+//! const NIST_P256_MODULUS: U256 =
+//!     U256::from_be_hex("FFFFFFFF00000000FFFFFFFFFFFFFFFFBCE6FAADA7179E84F3B9CAC2FC632551");
+//!
+//! // Public key for RFC6979 NIST P256/SHA256 test case
+//! const RFC6979_KEY: U256 =
+//!     U256::from_be_hex("C9AFA9D845BA75166B5C215767B1D6934E50C3DB36E89B127B8A622B120F6721");
+//!
+//! // Test message for RFC6979 NIST P256/SHA256 test case
+//! const RFC6979_MSG: &[u8; 6] = b"sample";
+//!
+//! // Expected K for RFC6979 NIST P256/SHA256 test case
+//! const RFC6979_EXPECTED_K: U256 =
+//!     U256::from_be_hex("A6E3C57DD01ABE90086538398355DD4C3B17AA873382B0F24D6129493D8AAD60");
+//!
+//! let h = Sha256::digest(RFC6979_MSG);
+//! let aad = b"";
+//! let k = rfc6979::generate_k::<Sha256, U256>(&RFC6979_KEY, &NIST_P256_MODULUS, &h, aad);
+//! assert_eq!(&k.to_be_byte_array(), &RFC6979_EXPECTED_K.to_be_byte_array());
+//! ```
+
+#![no_std]
+#![cfg_attr(docsrs, feature(doc_cfg))]
+#![forbid(unsafe_code, clippy::unwrap_used)]
+#![warn(missing_docs, rust_2018_idioms)]
+#![doc(
+    html_logo_url = "https://raw.githubusercontent.com/RustCrypto/media/8f1a9894/logo.svg",
+    html_favicon_url = "https://raw.githubusercontent.com/RustCrypto/media/8f1a9894/logo.svg"
+)]
+
+use crypto_bigint::{ArrayEncoding, ByteArray, Integer};
+use hmac::{
+    digest::{
+        core_api::BlockSizeUser, generic_array::GenericArray, Digest, FixedOutput,
+        FixedOutputReset, Mac,
+    },
+    SimpleHmac,
+};
+use zeroize::{Zeroize, Zeroizing};
+
+/// Deterministically generate ephemeral scalar `k`.
+///
+/// Accepts the following parameters and inputs:
+///
+/// - `x`: secret key
+/// - `n`: field modulus
+/// - `h`: hash/digest of input message: must be reduced modulo `n` in advance
+/// - `data`: additional associated data, e.g. CSRNG output used as added entropy
+#[inline]
+pub fn generate_k<D, I>(x: &I, n: &I, h: &ByteArray<I>, data: &[u8]) -> Zeroizing<I>
+where
+    D: Digest + BlockSizeUser + FixedOutput<OutputSize = I::ByteSize> + FixedOutputReset,
+    I: ArrayEncoding + Integer + Zeroize,
+{
+    let mut x = x.to_be_byte_array();
+    let mut hmac_drbg = HmacDrbg::<D>::new(&x, h, data);
+    x.zeroize();
+
+    loop {
+        let mut bytes = ByteArray::<I>::default();
+        hmac_drbg.fill_bytes(&mut bytes);
+        let k = I::from_be_byte_array(bytes);
+
+        if (!k.is_zero() & k.ct_lt(n)).into() {
+            return Zeroizing::new(k);
+        }
+    }
+}
+
+/// Internal implementation of `HMAC_DRBG` as described in NIST SP800-90A.
+///
+/// <https://csrc.nist.gov/publications/detail/sp/800-90a/rev-1/final>
+///
+/// This is a HMAC-based deterministic random bit generator used compute a
+/// deterministic ephemeral scalar `k`.
+pub struct HmacDrbg<D>
+where
+    D: Digest + BlockSizeUser + FixedOutputReset,
+{
+    /// HMAC key `K` (see RFC 6979 Section 3.2.c)
+    k: SimpleHmac<D>,
+
+    /// Chaining value `V` (see RFC 6979 Section 3.2.c)
+    v: GenericArray<u8, D::OutputSize>,
+}
+
+impl<D> HmacDrbg<D>
+where
+    D: Digest + BlockSizeUser + FixedOutputReset,
+{
+    /// Initialize `HMAC_DRBG`
+    pub fn new(entropy_input: &[u8], nonce: &[u8], additional_data: &[u8]) -> Self {
+        let mut k = SimpleHmac::new(&Default::default());
+        let mut v = GenericArray::default();
+
+        for b in &mut v {
+            *b = 0x01;
+        }
+
+        for i in 0..=1 {
+            k.update(&v);
+            k.update(&[i]);
+            k.update(entropy_input);
+            k.update(nonce);
+            k.update(additional_data);
+            k = SimpleHmac::new_from_slice(&k.finalize().into_bytes()).expect("HMAC error");
+
+            // Steps 3.2.e,g: v = HMAC_k(v)
+            k.update(&v);
+            v = k.finalize_reset().into_bytes();
+        }
+
+        Self { k, v }
+    }
+
+    /// Write the next `HMAC_DRBG` output to the given byte slice.
+    pub fn fill_bytes(&mut self, out: &mut [u8]) {
+        for out_chunk in out.chunks_mut(self.v.len()) {
+            self.k.update(&self.v);
+            self.v = self.k.finalize_reset().into_bytes();
+            out_chunk.copy_from_slice(&self.v[..out_chunk.len()]);
+        }
+
+        self.k.update(&self.v);
+        self.k.update(&[0x00]);
+        self.k =
+            SimpleHmac::new_from_slice(&self.k.finalize_reset().into_bytes()).expect("HMAC error");
+        self.k.update(&self.v);
+        self.v = self.k.finalize_reset().into_bytes();
+    }
+}
diff --git a/vendor/rfc6979/tests/lib.rs b/vendor/rfc6979/tests/lib.rs
new file mode 100644
index 000000000..1b622f8bd
--- /dev/null
+++ b/vendor/rfc6979/tests/lib.rs
@@ -0,0 +1,14 @@
+//! Smoke tests which use `MockCurve`
+
+#![cfg(feature = "dev")]
+
+use elliptic_curve::dev::MockCurve;
+
+type Signature = ecdsa::Signature<MockCurve>;
+type SignatureBytes = ecdsa::SignatureBytes<MockCurve>;
+
+#[test]
+fn rejects_all_zero_signature() {
+    let all_zero_bytes = SignatureBytes::default();
+    assert!(Signature::try_from(all_zero_bytes.as_ref()).is_err());
+}