Adding upstream version 86.0.1.upstream/86.0.1upstream

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

5 files changed, 87 insertions, 0 deletions

diff --git a/third_party/rust/constant_time_eq/.cargo-checksum.json b/third_party/rust/constant_time_eq/.cargo-checksum.json
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+++ b/third_party/rust/constant_time_eq/.cargo-checksum.json
@@ -0,0 +1 @@
+{"files":{"Cargo.toml":"2b23e4da7cb19c4d2e7a0816510558d369dc4f731ac83d5cb8fcce5534825213","README":"4f0deec2ec32eeabaa065fef2ddd7816a32550b8395da5c47fc458bd45143bea","benches/bench.rs":"ffc599703d114cc4943db322f433b0819787db0c1ff41d7be3efc5c0940e0001","src/lib.rs":"7abf980ba75361598e0250935c1de344c2d792ccccb4a3cf9243bbb9d3ad756e"},"package":"8ff012e225ce166d4422e0e78419d901719760f62ae2b7969ca6b564d1b54a9e"}
\ No newline at end of file
diff --git a/third_party/rust/constant_time_eq/Cargo.toml b/third_party/rust/constant_time_eq/Cargo.toml
new file mode 100644
index 0000000000..ae92925e9e
--- /dev/null
+++ b/third_party/rust/constant_time_eq/Cargo.toml
@@ -0,0 +1,14 @@
+[package]
+name = "constant_time_eq"
+version = "0.1.3"
+authors = ["Cesar Eduardo Barros <cesarb@cesarb.eti.br>"]
+description = "Compares two equal-sized byte strings in constant time."
+documentation = "https://docs.rs/constant_time_eq"
+repository = "https://github.com/cesarb/constant_time_eq"
+readme = "README"
+keywords = ["constant_time"]
+categories = ["cryptography", "no-std"]
+license = "CC0-1.0"
+
+[badges]
+travis-ci = { repository = "cesarb/constant_time_eq" }
diff --git a/third_party/rust/constant_time_eq/README b/third_party/rust/constant_time_eq/README
new file mode 100644
index 0000000000..98cdaf04ca
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+++ b/third_party/rust/constant_time_eq/README
@@ -0,0 +1,3 @@
+Compares two equal-sized byte strings in constant time.
+
+Inspired by the Linux kernel's crypto_memneq.
diff --git a/third_party/rust/constant_time_eq/benches/bench.rs b/third_party/rust/constant_time_eq/benches/bench.rs
new file mode 100644
index 0000000000..4b3b790a5d
--- /dev/null
+++ b/third_party/rust/constant_time_eq/benches/bench.rs
@@ -0,0 +1,29 @@
+#![feature(test)]
+
+extern crate constant_time_eq;
+extern crate test;
+
+use constant_time_eq::constant_time_eq;
+use test::{Bencher, black_box};
+
+fn bench(b: &mut Bencher, left: &[u8], right: &[u8]) {
+    b.bytes = (left.len() + right.len()) as u64;
+    b.iter(|| {
+        constant_time_eq(black_box(left), black_box(right))
+    })
+}
+
+#[bench]
+fn bench_16(b: &mut Bencher) {
+    bench(b, &[0; 16], &[0; 16])
+}
+
+#[bench]
+fn bench_4096(b: &mut Bencher) {
+    bench(b, &[0; 4096], &[0; 4096])
+}
+
+#[bench]
+fn bench_65536(b: &mut Bencher) {
+    bench(b, &[0; 65536], &[0; 65536])
+}
diff --git a/third_party/rust/constant_time_eq/src/lib.rs b/third_party/rust/constant_time_eq/src/lib.rs
new file mode 100644
index 0000000000..27a2d27a1a
--- /dev/null
+++ b/third_party/rust/constant_time_eq/src/lib.rs
@@ -0,0 +1,40 @@
+#![no_std]
+
+// This function is non-inline to prevent the optimizer from looking inside it.
+#[inline(never)]
+fn constant_time_ne(a: &[u8], b: &[u8]) -> u8 {
+    assert!(a.len() == b.len());
+
+    // These useless slices make the optimizer elide the bounds checks.
+    // See the comment in clone_from_slice() added on Rust commit 6a7bc47.
+    let len = a.len();
+    let a = &a[..len];
+    let b = &b[..len];
+
+    let mut tmp = 0;
+    for i in 0..len {
+        tmp |= a[i] ^ b[i];
+    }
+    tmp // The compare with 0 must happen outside this function.
+}
+
+/// Compares two equal-sized byte strings in constant time.
+///
+/// # Examples
+///
+/// ```
+/// use constant_time_eq::constant_time_eq;
+///
+/// assert!(constant_time_eq(b"foo", b"foo"));
+/// assert!(!constant_time_eq(b"foo", b"bar"));
+/// assert!(!constant_time_eq(b"bar", b"baz"));
+/// # assert!(constant_time_eq(b"", b""));
+///
+/// // Not equal-sized, so won't take constant time.
+/// assert!(!constant_time_eq(b"foo", b""));
+/// assert!(!constant_time_eq(b"foo", b"quux"));
+/// ```
+#[inline]
+pub fn constant_time_eq(a: &[u8], b: &[u8]) -> bool {
+    a.len() == b.len() && constant_time_ne(a, b) == 0
+}