Files
GmSSL/go/gmssl/hmac.go
2018-08-07 10:55:11 +08:00

128 lines
3.7 KiB
Go

/*
* Copyright (c) 2017 - 2018 The GmSSL Project. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* 3. All advertising materials mentioning features or use of this
* software must display the following acknowledgment:
* "This product includes software developed by the GmSSL Project.
* (http://gmssl.org/)"
*
* 4. The name "GmSSL Project" must not be used to endorse or promote
* products derived from this software without prior written
* permission. For written permission, please contact
* guanzhi1980@gmail.com.
*
* 5. Products derived from this software may not be called "GmSSL"
* nor may "GmSSL" appear in their names without prior written
* permission of the GmSSL Project.
*
* 6. Redistributions of any form whatsoever must retain the following
* acknowledgment:
* "This product includes software developed by the GmSSL Project
* (http://gmssl.org/)"
*
* THIS SOFTWARE IS PROVIDED BY THE GmSSL PROJECT ``AS IS'' AND ANY
* EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE GmSSL PROJECT OR
* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
* OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/* +build cgo */
package gmssl
/*
#include <openssl/hmac.h>
#include <openssl/cmac.h>
*/
import "C"
import (
"unsafe"
"runtime"
)
func GetMacLength(name string) (int, error) {
cname := C.CString(name)
defer C.free(unsafe.Pointer(cname))
md := C.EVP_get_digestbyname(cname)
if md == nil {
return 0, GetErrors()
}
return int(C.EVP_MD_size(md)), nil
}
type HMACContext struct {
hctx *C.HMAC_CTX
}
func NewHMACContext(name string, key []byte) (
*HMACContext, error) {
cname := C.CString(name)
defer C.free(unsafe.Pointer(cname))
md := C.EVP_get_digestbyname(cname)
if md == nil {
return nil, GetErrors()
}
ctx := C.HMAC_CTX_new()
if ctx == nil {
return nil, GetErrors()
}
ret := &HMACContext{ctx}
runtime.SetFinalizer(ret, func(ret *HMACContext) {
C.HMAC_CTX_free(ret.hctx)
})
if 1 != C.HMAC_Init_ex(ctx,
unsafe.Pointer(&key[0]), C.int(len(key)), md, nil) {
return nil, GetErrors()
}
return ret, nil
}
func (ctx *HMACContext) Update(data []byte) error {
if len(data) == 0 {
return nil
}
if 1 != C.HMAC_Update(ctx.hctx,
(*C.uchar)(unsafe.Pointer(&data[0])), C.size_t(len(data))) {
return GetErrors()
}
return nil
}
func (ctx *HMACContext) Final() ([]byte, error) {
outbuf := make([]byte, 64)
outlen := C.uint(len(outbuf))
if 1 != C.HMAC_Final(ctx.hctx,
(*C.uchar)(unsafe.Pointer(&outbuf[0])), &outlen) {
return nil, GetErrors()
}
return outbuf[:outlen], nil
}
func (ctx *HMACContext) Reset() error {
if 1 != C.HMAC_Init_ex(ctx.hctx, nil, 0, nil, nil) {
return GetErrors()
}
return nil
}