nxdumptool/include/core/aes.h

93 lines
2.7 KiB
C

/*
* aes.h
*
* Copyright (c) 2020-2021, DarkMatterCore <pabloacurielz@gmail.com>.
*
* This file is part of nxdumptool (https://github.com/DarkMatterCore/nxdumptool).
*
* nxdumptool is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* nxdumptool is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <https://www.gnu.org/licenses/>.
*/
#pragma once
#ifndef __AES_H__
#define __AES_H__
#ifdef __cplusplus
extern "C" {
#endif
/// Performs an AES-128-XTS crypto operation using the non-standard Nintendo XTS tweak.
/// The Aes128XtsContext element should have been previously initialized with aes128XtsContextCreate(). 'encrypt' should match the value of 'is_encryptor' used with that call.
/// 'dst' and 'src' can both point to the same address.
size_t aes128XtsNintendoCrypt(Aes128XtsContext *ctx, void *dst, const void *src, size_t size, u64 sector, size_t sector_size, bool encrypt);
/// Initializes an output AES partial counter using an initial CTR value and an offset.
/// The size for both 'out' and 'ctr' should be at least AES_BLOCK_SIZE.
NX_INLINE void aes128CtrInitializePartialCtr(u8 *out, const u8 *ctr, u64 offset)
{
if (!out || !ctr) return;
offset >>= 4;
for(u8 i = 0; i < 8; i++)
{
out[i] = ctr[0x8 - i - 1];
out[0x10 - i - 1] = (u8)(offset & 0xFF);
offset >>= 8;
}
}
/// Updates the provided AES partial counter using an offset.
/// 'out' size should be at least AES_BLOCK_SIZE.
NX_INLINE void aes128CtrUpdatePartialCtr(u8 *ctr, u64 offset)
{
if (!ctr) return;
offset >>= 4;
for(u8 i = 0; i < 8; i++)
{
ctr[0x10 - i - 1] = (u8)(offset & 0xFF);
offset >>= 8;
}
}
/// Updates the provided AES partial counter using an offset and a 32-bit CTR value.
/// 'out' size should be at least AES_BLOCK_SIZE.
NX_INLINE void aes128CtrUpdatePartialCtrEx(u8 *ctr, u32 ctr_val, u64 offset)
{
if (!ctr) return;
offset >>= 4;
for(u8 i = 0; i < 8; i++)
{
ctr[0x10 - i - 1] = (u8)(offset & 0xFF);
offset >>= 8;
}
for(u8 i = 0; i < 4; i++)
{
ctr[0x8 - i - 1] = (u8)(ctr_val & 0xFF);
ctr_val >>= 8;
}
}
#ifdef __cplusplus
}
#endif
#endif /* __AES_H__ */