Enable mounting of NCSD files

source/common.h

@@ -38,7 +38,7 @@
     (((v) % (a)) ? ((v) + (a) - ((v) % (a))) : (v))
     
 // GodMode9 version
-#define VERSION "0.7.6"
+#define VERSION "0.7.7"
 
 // buffer area defines (in use by godmode.c)
 #define DIR_BUFFER          (0x21000000)

source/filetype.c

@@ -1,5 +1,5 @@
 #include "filetype.h"
-#include "cia.h"
+#include "game.h"
 #include "ff.h"
 
 u32 IdentifyFileType(const char* path) {
@@ -36,7 +36,10 @@ u32 IdentifyFileType(const char* path) {
         GetCiaInfo(&info, (CiaHeader*) header);
         if (fsize >= info.size_cia)
             return GAME_CIA; // CIA file
-    } // more to come
+    } else if (ValidateNcsdHeader((NcsdHeader*) header) == 0) {
+        if (fsize >= (((NcsdHeader*) header)->size * NCSD_MEDIA_UNIT))
+            return GAME_NCSD; // NCSD (".3DS") file
+    } // NCCH still missing
     
     return 0;
 }

source/game/game.h

@@ -2,3 +2,4 @@
 
 #include "common.h"
 #include "cia.h"
+#include "ncsd.h"

source/game/ncsd.c

@@ -0,0 +1,22 @@
+#include "ncsd.h"
+
+u32 ValidateNcsdHeader(NcsdHeader* header) {
+    u8 zeroes[16] = { 0 };
+    if ((memcmp(header->magic, "NCSD", 4) != 0) || // check magic number
+        (memcmp(header->partitions_fs_type, zeroes, 8) != 0)) // prevent detection of NAND images
+        return 1;
+    
+    u32 data_units = 0;
+    for (u32 i = 0; i < 8; i++) {
+        NcchPartition* partition = header->partitions + i;
+        if ((partition->offset == 0) && (partition->size == 0))
+            continue;
+        if (partition->offset < data_units)
+            return 1; // overlapping partitions, failed
+        data_units = partition->offset + partition->size;
+    }
+    if (data_units > header->size)
+        return 1;
+     
+    return 0;
+}

source/game/ncsd.h

@@ -0,0 +1,30 @@
+#pragma once
+
+#include "common.h"
+
+#define NCSD_MEDIA_UNIT 0x200
+
+// see: https://www.3dbrew.org/wiki/NCSD
+typedef struct {
+	u32 offset;
+	u32 size;
+} __attribute__((packed)) NcchPartition;
+
+// see: https://www.3dbrew.org/wiki/NCSD
+typedef struct {
+	u8  signature[0x100];
+	u8  magic[4];
+	u32 size;
+	u64 mediaId;
+	u8  partitions_fs_type[8];
+	u8  partitions_crypto_type[8];
+	NcchPartition partitions[8];
+	u8  hash_exthdr[0x20];
+	u8  size_addhdr[0x4];
+	u8  sector_zero_offset[0x4];
+	u8  partition_flags[8];
+	u8  partitionId_table[8][8];
+	u8  reserved[0x40];
+} __attribute__((packed, aligned(16))) NcsdHeader;
+
+u32 ValidateNcsdHeader(NcsdHeader* header);

source/godmode.c

@@ -639,7 +639,8 @@ u32 GodMode() {
             if (mountable) optionstr[mountable-1] =
                 (file_type == IMG_NAND) ? "Mount as NAND image" :
                 (file_type == IMG_FAT) ? "Mount as FAT image" :
-                (file_type == GAME_CIA) ? "Mount as CIA image" : ""; // !!! NCCH / NCSD
+                (file_type == GAME_CIA) ? "Mount as CIA image" :
+                (file_type == GAME_NCSD) ? "Mount as NCSD image" : ""; // !!! NCCH
             if (searchdrv) optionstr[searchdrv-1] = "Open containing folder";
             
             u32 user_select = ShowSelectPrompt(n_opt, optionstr, pathstr);

source/virtual/vgame.c

@@ -14,10 +14,18 @@
 #define NAME_CIA_META       "meta.bin"
 #define NAME_CIA_CONTENT    "%04X.%08lX.app" // index.id.app
 
+#define NAME_NCSD_HEADER    "ncsd.bin"
+#define NAME_NCSD_CARDINFO  "cardinfo.bin"
+#define NAME_NCSD_DEVINFO   "devinfo.bin"
+#define NAME_NCSD_CONTENT   "cnt0.game.cxi", "cnt1.manual.cfa", "cnt2.dlp.cfa", \
+                            "cnt3.unk", "cnt4.unk", "cnt5.unk", \
+                            "cnt6.update_n3ds.cfa", "cnt7.update_o3ds.cfa"
+
 static u32 vgame_type = 0;
 static VirtualFile* templates = (VirtualFile*) VGAME_BUFFER; // first 128kb reserved
 static int n_templates = -1;
 
+static NcsdHeader* ncsd = (NcsdHeader*) (VGAME_BUFFER + 0xF3000); // needs only 512 byte
 static CiaStub* cia = (CiaStub*) (VGAME_BUFFER + 0xF4000); // 48kB reserved - should be enough by far
 
 u32 InitVGameDrive(void) { // prerequisite: game file mounted as image
@@ -30,7 +38,11 @@ u32 InitVGameDrive(void) { // prerequisite: game file mounted as image
             (GetCiaInfo(&info, &(cia->header)) != 0) ||
             (ReadImageBytes((u8*) cia, 0, info.offset_content) != 0))
             return 0;
-    } else if ((type == GAME_NCCH) || (type == GAME_NCSD)) {
+    } else if (type == GAME_NCSD) {
+        if ((ReadImageBytes((u8*) ncsd, 0, sizeof(NcsdHeader)) != 0) ||
+            (ValidateNcsdHeader(ncsd) != 0))
+            return 0;
+    } else if (type == GAME_NCCH) {
     } else return 0; // not a mounted game file
     
     vgame_type = type;
@@ -42,6 +54,56 @@ u32 CheckVGameDrive(void) {
     return vgame_type;
 }
 
+bool BuildVGameNcsdVDir(void) {
+    const char* name_content[] = { NAME_NCSD_CONTENT };
+    
+    if (CheckVGameDrive() != GAME_NCSD)
+        return false; // safety check
+    
+    // header
+    strncpy(templates[n_templates].name, NAME_NCSD_HEADER, 32);
+    templates[n_templates].offset = 0;
+    templates[n_templates].size = 0x200;
+    templates[n_templates].keyslot = 0xFF;
+    templates[n_templates].flags = 0;
+    n_templates++;
+    
+    // card info header
+    if (ncsd->partitions[0].offset * NCSD_MEDIA_UNIT >= 0x1200) {
+        strncpy(templates[n_templates].name, NAME_NCSD_CARDINFO, 32);
+        templates[n_templates].offset = 0x200;
+        templates[n_templates].size = 0x1000;
+        templates[n_templates].keyslot = 0xFF;
+        templates[n_templates].flags = 0;
+        n_templates++;
+    }
+    
+    // dev info header
+    if (ncsd->partitions[0].offset * NCSD_MEDIA_UNIT >= 0x1500) {
+        strncpy(templates[n_templates].name, NAME_NCSD_DEVINFO, 32);
+        templates[n_templates].offset = 0x1200;
+        templates[n_templates].size = 0x300;
+        templates[n_templates].keyslot = 0xFF;
+        templates[n_templates].flags = 0;
+        n_templates++;
+    }
+    
+    // contents
+    for (u32 i = 0; i < 8; i++) {
+        NcchPartition* partition = ncsd->partitions + i;
+        if ((partition->offset == 0) && (partition->size == 0))
+            continue;
+        strncpy(templates[n_templates].name, name_content[i], 32);
+        templates[n_templates].offset = partition->offset * NCSD_MEDIA_UNIT;
+        templates[n_templates].size = partition->size * NCSD_MEDIA_UNIT;
+        templates[n_templates].keyslot = 0xFF; // even for encrypted stuff
+        templates[n_templates].flags = 0; // this handles encryption
+        n_templates++;
+    }
+    
+    return true;
+}
+    
 bool BuildVGameCiaVDir(void) {
     CiaInfo info;
     
@@ -129,6 +191,7 @@ bool BuildVGameCiaVDir(void) {
 }
 
 bool ReadVGameDir(VirtualFile* vfile, const char* path) {
+    
     (void) path; // not in use yet
     static int num = -1;
     
@@ -136,9 +199,11 @@ bool ReadVGameDir(VirtualFile* vfile, const char* path) {
         num = -1; // reset dir reader / internal number
         memset(templates, 0, sizeof(VirtualFile) * MAX_N_TEMPLATES);
         n_templates = 0;
-        if (!BuildVGameCiaVDir()) // NCCH / NCSD !!!
-            return false;
-        return true;
+        if ((vgame_type == GAME_CIA) && BuildVGameCiaVDir()) // for CIA
+            return true;
+        else if ((vgame_type == GAME_NCSD) && BuildVGameNcsdVDir()) // for NCSD
+            return true;
+        return false;
     }
     
     if (++num < n_templates) {