Ydb stable 22-4-4322.4.43

x-stable-origin-commit: 8d49d46cc834835bf3e50870516acd7376a63bcf

2 files changed, 72 insertions, 0 deletions

diff --git a/contrib/go/_std_1.18/src/crypto/internal/randutil/randutil.go b/contrib/go/_std_1.18/src/crypto/internal/randutil/randutil.go
new file mode 100644
index 0000000000..84b1295a87
--- /dev/null
+++ b/contrib/go/_std_1.18/src/crypto/internal/randutil/randutil.go
@@ -0,0 +1,38 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package randutil contains internal randomness utilities for various
+// crypto packages.
+package randutil
+
+import (
+	"io"
+	"sync"
+)
+
+var (
+	closedChanOnce sync.Once
+	closedChan     chan struct{}
+)
+
+// MaybeReadByte reads a single byte from r with ~50% probability. This is used
+// to ensure that callers do not depend on non-guaranteed behaviour, e.g.
+// assuming that rsa.GenerateKey is deterministic w.r.t. a given random stream.
+//
+// This does not affect tests that pass a stream of fixed bytes as the random
+// source (e.g. a zeroReader).
+func MaybeReadByte(r io.Reader) {
+	closedChanOnce.Do(func() {
+		closedChan = make(chan struct{})
+		close(closedChan)
+	})
+
+	select {
+	case <-closedChan:
+		return
+	case <-closedChan:
+		var buf [1]byte
+		r.Read(buf[:])
+	}
+}
diff --git a/contrib/go/_std_1.18/src/crypto/internal/subtle/aliasing.go b/contrib/go/_std_1.18/src/crypto/internal/subtle/aliasing.go
new file mode 100644
index 0000000000..16e2fcab12
--- /dev/null
+++ b/contrib/go/_std_1.18/src/crypto/internal/subtle/aliasing.go
@@ -0,0 +1,34 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build !appengine
+
+// Package subtle implements functions that are often useful in cryptographic
+// code but require careful thought to use correctly.
+//
+// This is a mirror of golang.org/x/crypto/internal/subtle.
+package subtle // import "crypto/internal/subtle"
+
+import "unsafe"
+
+// AnyOverlap reports whether x and y share memory at any (not necessarily
+// corresponding) index. The memory beyond the slice length is ignored.
+func AnyOverlap(x, y []byte) bool {
+	return len(x) > 0 && len(y) > 0 &&
+		uintptr(unsafe.Pointer(&x[0])) <= uintptr(unsafe.Pointer(&y[len(y)-1])) &&
+		uintptr(unsafe.Pointer(&y[0])) <= uintptr(unsafe.Pointer(&x[len(x)-1]))
+}
+
+// InexactOverlap reports whether x and y share memory at any non-corresponding
+// index. The memory beyond the slice length is ignored. Note that x and y can
+// have different lengths and still not have any inexact overlap.
+//
+// InexactOverlap can be used to implement the requirements of the crypto/cipher
+// AEAD, Block, BlockMode and Stream interfaces.
+func InexactOverlap(x, y []byte) bool {
+	if len(x) == 0 || len(y) == 0 || &x[0] == &y[0] {
+		return false
+	}
+	return AnyOverlap(x, y)
+}