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#include "crypto/axtls/crypto.h"
#include <string.h>
#include <errno.h>
#include <gpxe/crypto.h>
#include <gpxe/aes.h>
struct aes_cbc_context {
AES_CTX ctx;
int decrypting;
};
static int aes_cbc_setkey ( void *ctx, const void *key, size_t keylen ) {
struct aes_cbc_context *aesctx = ctx;
AES_MODE mode;
switch ( keylen ) {
case ( 128 / 8 ):
mode = AES_MODE_128;
break;
case ( 256 / 8 ):
mode = AES_MODE_256;
break;
default:
return -EINVAL;
}
AES_set_key ( &aesctx->ctx, key, aesctx->ctx.iv, mode );
aesctx->decrypting = 0;
return 0;
}
static void aes_cbc_setiv ( void *ctx, const void *iv ) {
struct aes_cbc_context *aesctx = ctx;
memcpy ( aesctx->ctx.iv, iv, sizeof ( aesctx->ctx.iv ) );
}
static void aes_cbc_encrypt ( void *ctx, const void *data, void *dst,
size_t len ) {
struct aes_cbc_context *aesctx = ctx;
if ( aesctx->decrypting )
assert ( 0 );
AES_cbc_encrypt ( &aesctx->ctx, data, dst, len );
}
static void aes_cbc_decrypt ( void *ctx, const void *data, void *dst,
size_t len ) {
struct aes_cbc_context *aesctx = ctx;
if ( ! aesctx->decrypting ) {
AES_convert_key ( &aesctx->ctx );
aesctx->decrypting = 1;
}
AES_cbc_decrypt ( &aesctx->ctx, data, dst, len );
}
struct crypto_algorithm aes_cbc_algorithm = {
.name = "aes_cbc",
.ctxsize = sizeof ( struct aes_cbc_context ),
.blocksize = 16,
.setkey = aes_cbc_setkey,
.setiv = aes_cbc_setiv,
.encode = aes_cbc_encrypt,
.decode = aes_cbc_decrypt,
};
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