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authorGravatar Frédéric Guillot <fred@miniflux.net>2018-07-06 21:18:14 -0700
committerGravatar Frédéric Guillot <fred@miniflux.net>2018-07-06 21:18:14 -0700
commit459bb4531f92f8663afb6f36aa9be5b789bd591f (patch)
treef14e6c06b8e5c63612d1ff36f8cab40ae8a99d20 /vendor/golang.org/x/crypto/internal/subtle/aliasing_appengine.go
parent34a3fe426b33a63f2d8e02d4a70c88f137fa5410 (diff)
Update vendor dependencies
Diffstat (limited to 'vendor/golang.org/x/crypto/internal/subtle/aliasing_appengine.go')
-rw-r--r--vendor/golang.org/x/crypto/internal/subtle/aliasing_appengine.go35
1 files changed, 35 insertions, 0 deletions
diff --git a/vendor/golang.org/x/crypto/internal/subtle/aliasing_appengine.go b/vendor/golang.org/x/crypto/internal/subtle/aliasing_appengine.go
new file mode 100644
index 0000000..0cc4a8a
--- /dev/null
+++ b/vendor/golang.org/x/crypto/internal/subtle/aliasing_appengine.go
@@ -0,0 +1,35 @@
+// 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.
+
+// +build appengine
+
+// Package subtle implements functions that are often useful in cryptographic
+// code but require careful thought to use correctly.
+package subtle // import "golang.org/x/crypto/internal/subtle"
+
+// This is the Google App Engine standard variant based on reflect
+// because the unsafe package and cgo are disallowed.
+
+import "reflect"
+
+// 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 &&
+ reflect.ValueOf(&x[0]).Pointer() <= reflect.ValueOf(&y[len(y)-1]).Pointer() &&
+ reflect.ValueOf(&y[0]).Pointer() <= reflect.ValueOf(&x[len(x)-1]).Pointer()
+}
+
+// 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)
+}