summaryrefslogtreecommitdiffstats
path: root/vendor/github.com/Rhymen/go-whatsapp/crypto/hkdf
diff options
context:
space:
mode:
Diffstat (limited to 'vendor/github.com/Rhymen/go-whatsapp/crypto/hkdf')
-rw-r--r--vendor/github.com/Rhymen/go-whatsapp/crypto/hkdf/hkdf.go52
1 files changed, 0 insertions, 52 deletions
diff --git a/vendor/github.com/Rhymen/go-whatsapp/crypto/hkdf/hkdf.go b/vendor/github.com/Rhymen/go-whatsapp/crypto/hkdf/hkdf.go
deleted file mode 100644
index e0be0587..00000000
--- a/vendor/github.com/Rhymen/go-whatsapp/crypto/hkdf/hkdf.go
+++ /dev/null
@@ -1,52 +0,0 @@
-/*
-HKDF is a simple key derivation function (KDF) based on
-a hash-based message authentication code (HMAC). It was initially proposed by its authors as a building block in
-various protocols and applications, as well as to discourage the proliferation of multiple KDF mechanisms.
-The main approach HKDF follows is the "extract-then-expand" paradigm, where the KDF logically consists of two modules:
-the first stage takes the input keying material and "extracts" from it a fixed-length pseudorandom key, and then the
-second stage "expands" this key into several additional pseudorandom keys (the output of the KDF).
-*/
-package hkdf
-
-import (
- "crypto/hmac"
- "crypto/sha256"
- "fmt"
- "golang.org/x/crypto/hkdf"
- "io"
-)
-
-/*
-Expand expands a given key with the HKDF algorithm.
-*/
-func Expand(key []byte, length int, info string) ([]byte, error) {
- if info == "" {
- keyBlock := hmac.New(sha256.New, key)
- var out, last []byte
-
- var blockIndex byte = 1
- for i := 0; len(out) < length; i++ {
- keyBlock.Reset()
- //keyBlock.Write(append(append(last, []byte(info)...), blockIndex))
- keyBlock.Write(last)
- keyBlock.Write([]byte(info))
- keyBlock.Write([]byte{blockIndex})
- last = keyBlock.Sum(nil)
- blockIndex += 1
- out = append(out, last...)
- }
- return out[:length], nil
- } else {
- h := hkdf.New(sha256.New, key, nil, []byte(info))
- out := make([]byte, length)
- n, err := io.ReadAtLeast(h, out, length)
- if err != nil {
- return nil, err
- }
- if n != length {
- return nil, fmt.Errorf("new key to short")
- }
-
- return out[:length], nil
- }
-}