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-rw-r--r--vendor/golang.org/x/crypto/hkdf/hkdf.go75
1 files changed, 0 insertions, 75 deletions
diff --git a/vendor/golang.org/x/crypto/hkdf/hkdf.go b/vendor/golang.org/x/crypto/hkdf/hkdf.go
deleted file mode 100644
index 5bc246355..000000000
--- a/vendor/golang.org/x/crypto/hkdf/hkdf.go
+++ /dev/null
@@ -1,75 +0,0 @@
-// Copyright 2014 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 hkdf implements the HMAC-based Extract-and-Expand Key Derivation
-// Function (HKDF) as defined in RFC 5869.
-//
-// HKDF is a cryptographic key derivation function (KDF) with the goal of
-// expanding limited input keying material into one or more cryptographically
-// strong secret keys.
-//
-// RFC 5869: https://tools.ietf.org/html/rfc5869
-package hkdf // import "golang.org/x/crypto/hkdf"
-
-import (
- "crypto/hmac"
- "errors"
- "hash"
- "io"
-)
-
-type hkdf struct {
- expander hash.Hash
- size int
-
- info []byte
- counter byte
-
- prev []byte
- cache []byte
-}
-
-func (f *hkdf) Read(p []byte) (int, error) {
- // Check whether enough data can be generated
- need := len(p)
- remains := len(f.cache) + int(255-f.counter+1)*f.size
- if remains < need {
- return 0, errors.New("hkdf: entropy limit reached")
- }
- // Read from the cache, if enough data is present
- n := copy(p, f.cache)
- p = p[n:]
-
- // Fill the buffer
- for len(p) > 0 {
- f.expander.Reset()
- f.expander.Write(f.prev)
- f.expander.Write(f.info)
- f.expander.Write([]byte{f.counter})
- f.prev = f.expander.Sum(f.prev[:0])
- f.counter++
-
- // Copy the new batch into p
- f.cache = f.prev
- n = copy(p, f.cache)
- p = p[n:]
- }
- // Save leftovers for next run
- f.cache = f.cache[n:]
-
- return need, nil
-}
-
-// New returns a new HKDF using the given hash, the secret keying material to expand
-// and optional salt and info fields.
-func New(hash func() hash.Hash, secret, salt, info []byte) io.Reader {
- if salt == nil {
- salt = make([]byte, hash().Size())
- }
- extractor := hmac.New(hash, salt)
- extractor.Write(secret)
- prk := extractor.Sum(nil)
-
- return &hkdf{hmac.New(hash, prk), extractor.Size(), info, 1, nil, nil}
-}