92 lines
2.2 KiB
Go
92 lines
2.2 KiB
Go
// Copyright (C) 2017. See AUTHORS.
|
|
//
|
|
// Licensed under the Apache License, Version 2.0 (the "License");
|
|
// you may not use this file except in compliance with the License.
|
|
// You may obtain a copy of the License at
|
|
//
|
|
// http://www.apache.org/licenses/LICENSE-2.0
|
|
//
|
|
// Unless required by applicable law or agreed to in writing, software
|
|
// distributed under the License is distributed on an "AS IS" BASIS,
|
|
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
// See the License for the specific language governing permissions and
|
|
// limitations under the License.
|
|
|
|
package openssl
|
|
|
|
// #include "shim.h"
|
|
import "C"
|
|
|
|
import (
|
|
"errors"
|
|
"runtime"
|
|
"unsafe"
|
|
)
|
|
|
|
type HMAC struct {
|
|
ctx *C.HMAC_CTX
|
|
engine *Engine
|
|
md *C.EVP_MD
|
|
}
|
|
|
|
func NewHMAC(key []byte, digestAlgorithm EVP_MD) (*HMAC, error) {
|
|
return NewHMACWithEngine(key, digestAlgorithm, nil)
|
|
}
|
|
|
|
func NewHMACWithEngine(key []byte, digestAlgorithm EVP_MD, e *Engine) (*HMAC, error) {
|
|
var md *C.EVP_MD = getDigestFunction(digestAlgorithm)
|
|
h := &HMAC{engine: e, md: md}
|
|
h.ctx = C.X_HMAC_CTX_new()
|
|
if h.ctx == nil {
|
|
return nil, errors.New("unable to allocate HMAC_CTX")
|
|
}
|
|
|
|
var c_e *C.ENGINE
|
|
if e != nil {
|
|
c_e = e.e
|
|
}
|
|
if rc := C.X_HMAC_Init_ex(h.ctx,
|
|
unsafe.Pointer(&key[0]),
|
|
C.int(len(key)),
|
|
md,
|
|
c_e); rc != 1 {
|
|
C.X_HMAC_CTX_free(h.ctx)
|
|
return nil, errors.New("failed to initialize HMAC_CTX")
|
|
}
|
|
|
|
runtime.SetFinalizer(h, func(h *HMAC) { h.Close() })
|
|
return h, nil
|
|
}
|
|
|
|
func (h *HMAC) Close() {
|
|
C.X_HMAC_CTX_free(h.ctx)
|
|
}
|
|
|
|
func (h *HMAC) Write(data []byte) (n int, err error) {
|
|
if len(data) == 0 {
|
|
return 0, nil
|
|
}
|
|
if rc := C.X_HMAC_Update(h.ctx, (*C.uchar)(unsafe.Pointer(&data[0])),
|
|
C.size_t(len(data))); rc != 1 {
|
|
return 0, errors.New("failed to update HMAC")
|
|
}
|
|
return len(data), nil
|
|
}
|
|
|
|
func (h *HMAC) Reset() error {
|
|
if C.X_HMAC_Init_ex(h.ctx, nil, 0, nil, nil) != 1 {
|
|
return errors.New("failed to reset HMAC_CTX")
|
|
}
|
|
return nil
|
|
}
|
|
|
|
func (h *HMAC) Final() (result []byte, err error) {
|
|
mdLength := C.X_EVP_MD_size(h.md)
|
|
result = make([]byte, mdLength)
|
|
if rc := C.X_HMAC_Final(h.ctx, (*C.uchar)(unsafe.Pointer(&result[0])),
|
|
(*C.uint)(unsafe.Pointer(&mdLength))); rc != 1 {
|
|
return nil, errors.New("failed to finalized HMAC")
|
|
}
|
|
return result, h.Reset()
|
|
}
|