storage: Add primitive BIS support

nyx/nyx_gui/libs/fatfs/diskio.c

@@ -11,6 +11,7 @@
 
 #include "diskio.h"		/* FatFs lower layer API */
 #include "../../../../common/memory_map.h"
+#include "../../storage/nx_emmc_bis.h"
 #include "../../storage/nx_sd.h"
 #include "../../storage/ramdisk.h"
 #include "../../storage/sdmmc.h"
@@ -51,6 +52,10 @@ DRESULT disk_read (
 		return sdmmc_storage_read(&sd_storage, sector, count, (void *)buff) ? RES_OK : RES_ERROR;
 	case DRIVE_RAM:
 		return ram_disk_read(sector, count, (void *)buff);
+	case DRIVE_EMMC:
+		return sdmmc_storage_read(&emmc_storage, sector, count, (void *)buff) ? RES_OK : RES_ERROR;
+	case DRIVE_BIS:
+		return nx_emmc_bis_read(sector, count, (void *)buff);
 	}
 
 	return RES_ERROR;
@@ -72,6 +77,9 @@ DRESULT disk_write (
 		return sdmmc_storage_write(&sd_storage, sector, count, (void *)buff) ? RES_OK : RES_ERROR;
 	case DRIVE_RAM:
 		return ram_disk_write(sector, count, (void *)buff);
+	case DRIVE_EMMC:
+	case DRIVE_BIS:
+		return RES_WRPRT;
 	}
 
 	return RES_ERROR;

nyx/nyx_gui/libs/fatfs/diskio.h

@@ -26,6 +26,8 @@ typedef enum {
 typedef enum {
 	DRIVE_SD   = 0,
 	DRIVE_RAM  = 1,
+	DRIVE_EMMC = 2,
+	DRIVE_BIS  = 3
 } DDRIVE;
 
 

nyx/nyx_gui/libs/fatfs/ffconf.h

@@ -168,13 +168,13 @@
 / Drive/Volume Configurations
 /---------------------------------------------------------------------------*/
 
-#define FF_VOLUMES		2
+#define FF_VOLUMES		4
 /* Number of volumes (logical drives) to be used. (1-10) */
 
 
 #define FF_STR_VOLUME_ID	1
 // Order is important. Any change to order, must also be reflected to diskio drive enum.
-#define FF_VOLUME_STRS		"sd","ram"
+#define FF_VOLUME_STRS		"sd","ram","emmc","bis"
 /* FF_STR_VOLUME_ID switches support for volume ID in arbitrary strings.
 /  When FF_STR_VOLUME_ID is set to 1 or 2, arbitrary strings can be used as drive
 /  number in the path name. FF_VOLUME_STRS defines the volume ID strings for each

nyx/nyx_gui/storage/nx_emmc_bis.c

@@ -0,0 +1,185 @@
+/*
+ * eMMC BIS driver for Nintendo Switch
+ *
+ * Copyright (c) 2019 shchmue
+ * Copyright (c) 2019 CTCaer
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope 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 <http://www.gnu.org/licenses/>.
+ */
+
+#include <string.h>
+
+#include "../../../common/memory_map.h"
+
+#include "../sec/se.h"
+#include "../storage/nx_emmc.h"
+#include "../storage/sdmmc.h"
+#include "../utils/types.h"
+
+#define MAX_SEC_CACHE_ENTRIES 64
+
+typedef struct _sector_cache_t
+{
+	u32 sector;
+	u32 visit_cnt;
+	u8  tweak[0x10];
+	u8  data[0x200];
+	u8  align[8];
+} sector_cache_t;
+
+static u32 sector_idx = 0;
+static sector_cache_t *sector_cache = NULL;
+static emmc_part_t *system_part = NULL;
+
+static void _gf256_mul_x_le(u8 *block)
+{
+	u8 *pdata = (u8 *)block;
+	u32 carry = 0;
+
+	for (u32 i = 0; i < 0x10; i++)
+	{
+		u8 b = pdata[i];
+		pdata[i] = (b << 1) | carry;
+		carry = b >> 7;
+	}
+
+	if (carry)
+		pdata[0x0] ^= 0x87;
+}
+
+static int _nx_aes_xts_crypt_sec(u32 ks1, u32 ks2, u32 enc, u8 *tweak, bool regen_tweak, u32 tweak_exp, u64 sec, void *dst, void *src, u32 sec_size)
+{
+	u8 *pdst = (u8 *)dst;
+	u8 *psrc = (u8 *)src;
+
+	if (regen_tweak)
+	{
+		for (int i = 0xF; i >= 0; i--)
+		{
+			tweak[i] = sec & 0xFF;
+			sec >>= 8;
+		}
+		if (!se_aes_crypt_block_ecb(ks1, 1, tweak, tweak))
+			return 0;
+	}
+
+	for (u32 i = 0; i < (tweak_exp << 5); i++)
+		_gf256_mul_x_le(tweak);
+
+	u8 tmp_tweak[0x10];
+	memcpy(tmp_tweak, tweak, 0x10);
+
+	// We are assuming a 0x10-aligned sector size in this implementation.
+	for (u32 i = 0; i < (sec_size >> 4); i++)
+	{
+		for (u32 j = 0; j < 0x10; j++)
+			pdst[j] = psrc[j] ^ tweak[j];
+
+		_gf256_mul_x_le(tweak);
+		psrc += 0x10;
+		pdst += 0x10;
+	}
+
+	se_aes_crypt_ecb(ks2, 0, dst, sec_size, src, sec_size);
+
+	memcpy(tweak, tmp_tweak, 0x10);
+
+	pdst = (u8 *)dst;
+	for (u32 i = 0; i < (sec_size >> 4); i++)
+	{
+		for (u32 j = 0; j < 0x10; j++)
+			pdst[j] = pdst[j] ^ tweak[j];
+
+		_gf256_mul_x_le(tweak);
+		pdst += 0x10;
+	}
+
+	return 1;
+}
+
+int nx_emmc_bis_read(u32 sector, u32 count, void *buff)
+{
+	if (!system_part)
+		return 3; // Not ready.
+
+	static u32 prev_cluster = -1;
+	static u32 prev_sector = 0;
+	__attribute__ ((aligned (16))) static u8 tweak[0x10];
+
+	u32 tweak_exp = 0;
+	bool regen_tweak = true, cache_sector = false;
+
+	if (!sector_cache)
+		sector_cache = (sector_cache_t *)NX_BIS_CACHE_ADDR;
+
+	u32 cache_idx = 0;
+	if (count == 1)
+	{
+		for ( ; cache_idx < sector_idx; cache_idx++)
+		{
+			if (sector_cache[cache_idx].sector == sector)
+			{
+				sector_cache[cache_idx].visit_cnt++;
+				memcpy(buff, sector_cache[cache_idx].data, 0x200);
+				memcpy(tweak, sector_cache[cache_idx].tweak, 0x10);
+				prev_sector = sector;
+				prev_cluster = sector >> 5;
+
+				return 0;
+			}
+		}
+		// add to cache
+		if (cache_idx == sector_idx && cache_idx < MAX_SEC_CACHE_ENTRIES)
+		{
+			sector_cache[cache_idx].sector = sector;
+			sector_cache[cache_idx].visit_cnt++;
+			cache_sector = true;
+			sector_idx++;
+		}
+	}
+
+	if (nx_emmc_part_read(&emmc_storage, system_part, sector, count, buff))
+	{
+		if (prev_cluster != sector >> 5) // Sector in different cluster than last read.
+		{
+			prev_cluster = sector >> 5;
+			tweak_exp = sector % 0x20;
+		}
+		else if (sector > prev_sector) // Sector in same cluster and past last sector.
+		{
+			tweak_exp = sector - prev_sector - 1;
+			regen_tweak = false;
+		}
+		else // Sector in same cluster and before or same as last sector.
+			tweak_exp = sector % 0x20;
+
+		// FatFS will never pull more than a cluster.
+		_nx_aes_xts_crypt_sec(9, 8, 0, tweak, regen_tweak, tweak_exp, prev_cluster, buff, buff, count << 9);
+		if (cache_sector)
+		{
+			memcpy(sector_cache[cache_idx].data, buff, 0x200);
+			memcpy(sector_cache[cache_idx].tweak, tweak, 0x10);
+		}
+		prev_sector = sector + count - 1;
+
+		return 0;
+	}
+
+	// Error occurred.
+	return 1;
+}
+
+void nx_emmc_bis_init(emmc_part_t *part)
+{
+	system_part = part;
+}

nyx/nyx_gui/storage/nx_emmc_bis.h

@@ -0,0 +1,27 @@
+/*
+ * Copyright (c) 2019 shchmue
+ * Copyright (c) 2019 CTCaer
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope 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 <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef NX_EMMC_BIS_H
+#define NX_EMMC_BIS_H
+
+#include "../storage/nx_emmc.h"
+#include "../storage/sdmmc.h"
+
+int nx_emmc_bis_read(u32 sector, u32 count, void *buff);
+void nx_emmc_bis_init(sdmmc_storage_t *storage, emmc_part_t *part);
+
+#endif