132 lines
3.7 KiB
C
132 lines
3.7 KiB
C
/*
|
|
* Copyright 2016 Dius Computing Pty Ltd. All rights reserved.
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions
|
|
* are met:
|
|
*
|
|
* - Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
* - 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.
|
|
* - Neither the name of the copyright holders nor the names of
|
|
* its contributors may be used to endorse or promote products derived
|
|
* from this software without specific prior written permission.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
|
|
* "AS IS" AND ANY EXPRESS 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 COPYRIGHT HOLDER OR 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.
|
|
*
|
|
* @author Johny Mattsson <jmattsson@dius.com.au>
|
|
*/
|
|
|
|
#include "mech.h"
|
|
#include "sdk-aes.h"
|
|
#include "c_string.h"
|
|
|
|
/* ----- AES ---------------------------------------------------------- */
|
|
|
|
static const struct aes_funcs
|
|
{
|
|
void *(*init) (const char *key, size_t keylen);
|
|
void (*crypt) (void *ctx, const char *in, char *out);
|
|
void (*deinit) (void *ctx);
|
|
} aes_funcs[] =
|
|
{
|
|
{ aes_encrypt_init, aes_encrypt, aes_encrypt_deinit },
|
|
{ aes_decrypt_init, aes_decrypt, aes_decrypt_deinit }
|
|
};
|
|
|
|
static bool do_aes (crypto_op_t *co, bool with_cbc)
|
|
{
|
|
const struct aes_funcs *funcs = &aes_funcs[co->op];
|
|
|
|
void *ctx = funcs->init (co->key, co->keylen);
|
|
if (!ctx)
|
|
return false;
|
|
|
|
char iv[AES_BLOCKSIZE] = { 0 };
|
|
if (with_cbc && co->ivlen)
|
|
c_memcpy (iv, co->iv, co->ivlen < AES_BLOCKSIZE ? co->ivlen : AES_BLOCKSIZE);
|
|
|
|
const char *src = co->data;
|
|
char *dst = co->out;
|
|
|
|
size_t left = co->datalen;
|
|
while (left)
|
|
{
|
|
char block[AES_BLOCKSIZE] = { 0 };
|
|
size_t n = left > AES_BLOCKSIZE ? AES_BLOCKSIZE : left;
|
|
c_memcpy (block, src, n);
|
|
|
|
if (with_cbc && co->op == OP_ENCRYPT)
|
|
{
|
|
const char *xor = (src == co->data) ? iv : dst - AES_BLOCKSIZE;
|
|
int i;
|
|
for (i = 0; i < AES_BLOCKSIZE; ++i)
|
|
block[i] ^= xor[i];
|
|
}
|
|
|
|
funcs->crypt (ctx, block, dst);
|
|
|
|
if (with_cbc && co->op == OP_DECRYPT)
|
|
{
|
|
const char *xor = (src == co->data) ? iv : src - AES_BLOCKSIZE;
|
|
int i;
|
|
for (i = 0; i < AES_BLOCKSIZE; ++i)
|
|
dst[i] ^= xor[i];
|
|
}
|
|
|
|
left -= n;
|
|
src += n;
|
|
dst += n;
|
|
}
|
|
|
|
funcs->deinit (ctx);
|
|
return true;
|
|
}
|
|
|
|
|
|
static bool do_aes_ecb (crypto_op_t *co)
|
|
{
|
|
return do_aes (co, false);
|
|
}
|
|
|
|
static bool do_aes_cbc (crypto_op_t *co)
|
|
{
|
|
return do_aes (co, true);
|
|
}
|
|
|
|
|
|
/* ----- mechs -------------------------------------------------------- */
|
|
|
|
static const crypto_mech_t mechs[] =
|
|
{
|
|
{ "AES-ECB", do_aes_ecb, AES_BLOCKSIZE },
|
|
{ "AES-CBC", do_aes_cbc, AES_BLOCKSIZE }
|
|
};
|
|
|
|
|
|
const crypto_mech_t *crypto_encryption_mech (const char *name)
|
|
{
|
|
size_t i;
|
|
for (i = 0; i < sizeof (mechs) / sizeof (mechs[0]); ++i)
|
|
{
|
|
const crypto_mech_t *mech = mechs + i;
|
|
if (strcasecmp (name, mech->name) == 0)
|
|
return mech;
|
|
}
|
|
return 0;
|
|
}
|