Changes to the gamecard key area handling.

source/gamecard.c

@@ -48,7 +48,7 @@ typedef struct {
     u8 card_id_area[0x48];
     u8 reserved[0x1B0];
     FsGameCardCertificate certificate;
-    GameCardKeyArea key_area;
+    GameCardInitialData initial_data;
 } GameCardSecurityInformation;
 
 typedef struct {
@@ -114,6 +114,7 @@ static MemoryLocation g_fsProgramMemory = {
 };
 
 static GameCardSecurityInformation g_gameCardSecurityInfo = {0};
+static GameCardKeyArea g_gameCardKeyArea = {0};
 
 /* Function prototypes. */
 
@@ -278,7 +279,7 @@ bool gamecardGetKeyArea(GameCardKeyArea *out)
 {
     mutexLock(&g_gamecardMutex);
     bool ret = (g_gameCardInserted && g_gameCardInfoLoaded && out);
-    if (ret) memcpy(out, &(g_gameCardSecurityInfo.key_area), sizeof(GameCardKeyArea));
+    if (ret) memcpy(out, &g_gameCardKeyArea, sizeof(GameCardKeyArea));
     mutexUnlock(&g_gamecardMutex);
     return ret;
 }
@@ -711,10 +712,10 @@ static void gamecardLoadInfo(void)
         }
     }
     
-    /* Read full FS program memory to retrieve the GameCardSecurityInformation data, which holds the gamecard key area. */
+    /* Read full FS program memory to retrieve the GameCardSecurityInformation data, which holds the gamecard initial data area. */
     /* This must be performed while the gamecard is in secure mode, which is already taken care of in the gamecardReadStorageArea() calls from the last iteration in the previous for() loop. */
     /* GameCardSecurityInformation data is returned by Lotus command "ChangeToSecureMode" (0xF), and kept in FS program memory only after the gamecard secure area has been both mounted and read from. */
-    /* Under some circumstances, the gamecard key area is located *after* the GameCardSecurityInformation area (offset 0x600), instead of its common location at offset 0x400. */
+    /* Under some circumstances, the gamecard initial data is located *after* the GameCardSecurityInformation area (offset 0x600), instead of its common location at offset 0x400. */
     if (!gamecardReadSecurityInformation())
     {
         LOGFILE("Failed to read gamecard security information area from FS program memory!");
@@ -732,6 +733,7 @@ static void gamecardFreeInfo(void)
     memset(&g_gameCardHeader, 0, sizeof(GameCardHeader));
     
     memset(&g_gameCardSecurityInfo, 0, sizeof(GameCardSecurityInformation));
+    memset(&g_gameCardKeyArea, 0, sizeof(GameCardKeyArea));
     
     g_gameCardStorageNormalAreaSize = 0;
     g_gameCardStorageSecureAreaSize = 0;
@@ -786,21 +788,26 @@ static bool gamecardReadSecurityInformation(void)
         memcpy(&g_gameCardSecurityInfo, g_fsProgramMemory.data + offset, sizeof(GameCardSecurityInformation));
         
         /* Check the key_source / package_id value. */
-        if (g_gameCardSecurityInfo.key_area.package_id == g_gameCardHeader.package_id)
+        if (g_gameCardSecurityInfo.initial_data.package_id == g_gameCardHeader.package_id)
         {
             /* Jackpot. */
             found = true;
         } else {
-            /* Copy the sector right after the GameCardSecurityInformation element from the memory dump, since it may hold the gamecard key area. */
+            /* Copy the sector right after the GameCardSecurityInformation element from the memory dump, since it may hold the gamecard initial data. */
             offset += sizeof(GameCardSecurityInformation);
-            memcpy(&(g_gameCardSecurityInfo.key_area), g_fsProgramMemory.data + offset, sizeof(GameCardKeyArea));
-            found = (g_gameCardSecurityInfo.key_area.package_id == g_gameCardHeader.package_id);
+            memcpy(&(g_gameCardSecurityInfo.initial_data), g_fsProgramMemory.data + offset, sizeof(GameCardInitialData));
+            found = (g_gameCardSecurityInfo.initial_data.package_id == g_gameCardHeader.package_id);
         }
         
         break;
     }
     
-    if (!found) LOGFILE("Failed to locate gamecard key area!");
+    if (found)
+    {
+        memcpy(&(g_gameCardKeyArea.initial_data), &(g_gameCardSecurityInfo.initial_data), sizeof(GameCardInitialData));
+    } else {
+        LOGFILE("Failed to locate gamecard initial data area!");
+    }
     
     /* Free FS memory dump. */
     memFreeMemoryLocation(&g_fsProgramMemory);

source/gamecard.h

@@ -36,18 +36,40 @@
                                         ((x) == GameCardHashFileSystemPartitionType_Logo ? "logo" : ((x) == GameCardHashFileSystemPartitionType_Normal ? "normal" : \
                                         ((x) == GameCardHashFileSystemPartitionType_Secure ? "secure" : "unknown")))))
 
+/// Plaintext area. Dumped from FS program memory.
 typedef struct {
     union {
-        u8 key_source[0x10];
+        u8 key_source[0x10];        ///< Encrypted using AES-128-ECB with the common titlekek generator key (stored in the .rodata segment from the Lotus firmware).
         struct {
-            u64 package_id;     ///< Matches package_id from GameCardHeader.
-            u64 padding;        ///< Just zeroes.
+            u64 package_id;         ///< Matches package_id from GameCardHeader.
+            u64 padding;            ///< Just zeroes.
         };
     };
-    u8 encrypted_titlekey[0x10];
-    u8 mac[0x10];
-    u8 nonce[0xC];
+    u8 encrypted_titlekey[0x10];    ///< Encrypted using AES-128-CCM with the decrypted key_source and the nonce from this section.
+    u8 mac[0x10];                   ///< Used to verify the validity of the decrypted titlekey.
+    u8 nonce[0xC];                  ///< Used as the IV to decrypt the key_source using AES-128-CCM.
     u8 reserved[0x1C4];
+} GameCardInitialData;
+
+/// Encrypted using AES-128-CTR with the key and IV/counter from the `GameCardTitleKeyEncryption` section. Assumed to be all zeroes in retail gamecards.
+typedef struct {
+    u8 titlekey[0x10];  ///< Decrypted titlekey from the `GameCardInitialData` section.
+    u8 reserved[0xCF0];
+} GameCardTitleKey;
+
+/// Encrypted using RSA-2048-OAEP. Assumed to be all zeroes in retail gamecards.
+typedef struct {
+    u8 titlekey_encryption_key[0x10];   ///< Used as the AES-128-CTR key for the `GameCardTitleKey` section.
+    u8 titlekey_encryption_iv[0x10];    ///< Used as the AES-128-CTR IV/counter for the `GameCardTitleKey` section.
+    u8 reserved[0xE0];
+} GameCardTitleKeyEncryption;
+
+/// Used to secure communications between the Lotus and the inserted gamecard.
+/// Precedes the gamecard header.
+typedef struct {
+    GameCardInitialData initial_data;
+    GameCardTitleKey titlekey_block;
+    GameCardTitleKeyEncryption titlekey_encryption;
 } GameCardKeyArea;
 
 typedef enum {
@@ -99,21 +121,38 @@ typedef enum {
 } GameCardCompatibilityType;
 
 typedef struct {
-    u64 fw_version;         ///< GameCardFwVersion.
-    u32 acc_ctrl;           ///< GameCardAccCtrl.
-    u32 wait_1_time_read;   ///< Always 0x1388.
-    u32 wait_2_time_read;   ///< Always 0.
-    u32 wait_1_time_write;  ///< Always 0.
-    u32 wait_2_time_write;  ///< Always 0.
-    u32 fw_mode;
-    u32 upp_version;
-    u8 compatibility_type;  ///< GameCardCompatibilityType.
+    u32 GameCardFwMode_Relstep : 8;
+    u32 GameCardFwMode_Micro   : 8;
+    u32 GameCardFwMode_Minor   : 8;
+    u32 GameCardFwMode_Major   : 8;
+} GameCardFwMode;
+
+typedef struct {
+    u32 GameCardUppVersion_MinorRelstep : 8;
+    u32 GameCardUppVersion_MajorRelstep : 8;
+    u32 GameCardUppVersion_Micro        : 4;
+    u32 GameCardUppVersion_Minor        : 6;
+    u32 GameCardUppVersion_Major        : 6;
+} GameCardUppVersion;
+
+/// Encrypted using AES-128-CBC with the `xci_header_key` (which can't dumped through current methods) and the IV from `GameCardHeader`.
+typedef struct {
+    u64 fw_version;                 ///< GameCardFwVersion.
+    u32 acc_ctrl;                   ///< GameCardAccCtrl.
+    u32 wait_1_time_read;           ///< Always 0x1388.
+    u32 wait_2_time_read;           ///< Always 0.
+    u32 wait_1_time_write;          ///< Always 0.
+    u32 wait_2_time_write;          ///< Always 0.
+    GameCardFwMode fw_mode;
+    GameCardUppVersion upp_version;
+    u8 compatibility_type;          ///< GameCardCompatibilityType.
     u8 reserved_1[0x3];
     u64 upp_hash;
-    u64 upp_id;             ///< Must match GAMECARD_UPDATE_TID.
+    u64 upp_id;                     ///< Must match GAMECARD_UPDATE_TID.
     u8 reserved_2[0x38];
-} GameCardExtendedHeader;
+} GameCardHeaderEncryptedArea;
 
+/// Placed after the `GameCardKeyArea` section.
 typedef struct {
     u8 signature[0x100];                            ///< RSA-2048 PKCS #1 signature over the rest of the header.
     u32 magic;                                      ///< "HEAD".
@@ -135,7 +174,7 @@ typedef struct {
     u32 sel_t1_key_index;
     u32 sel_key_index;
     u32 normal_area_end_address;                    ///< Expressed in GAMECARD_MEDIA_UNIT_SIZE blocks.
-    GameCardExtendedHeader extended_header;         ///< Encrypted using AES-128-CBC with 'xci_header_key', which can't dumped through current methods.
+    GameCardHeaderEncryptedArea encrypted_area;
 } GameCardHeader;
 
 typedef enum {

source/nca.h

@@ -75,10 +75,10 @@ typedef enum {
 } NcaKeyAreaEncryptionKeyIndex;
 
 typedef struct {
-    u8 relstep;
-    u8 micro;
-    u8 minor;
-    u8 major;
+    u32 NcaSdkAddOnVersion_Relstep : 8;
+    u32 NcaSdkAddOnVersion_Micro   : 8;
+    u32 NcaSdkAddOnVersion_Minor   : 8;
+    u32 NcaSdkAddOnVersion_Major   : 8;
 } NcaSdkAddOnVersion;
 
 /// 'NcaKeyGeneration_Current' will always point to the last known key generation value.

source/romfs.h

@@ -101,6 +101,7 @@ typedef struct {
     u64 file_table_size;                            ///< RomFS file entries table size.
     RomFileSystemFileEntry *file_table;             ///< RomFS file entries table.
     u64 body_offset;                                ///< RomFS file data body offset (relative to the start of the RomFS).
+    u32 cur_dir_offset;                             ///< Current RomFS directory offset (relative to the start of the directory entries table). Used for RomFS browsing.
 } RomFileSystemContext;
 
 typedef struct {

source/rsa.h

@@ -34,7 +34,7 @@ bool rsa2048GenerateSha256BasedCustomAcidSignature(void *dst, const void *src, s
 /// Suitable to replace the ACID public key in main.npdm files.
 const u8 *rsa2048GetCustomAcidPublicKey(void);
 
-/// Performs RSA-2048 OAEP decryption and verification. Used to decrypt the titlekey block from tickets with personalized crypto.
+/// Performs RSA-2048-OAEP decryption and verification. Used to decrypt the titlekey block from tickets with personalized crypto.
 bool rsa2048OaepDecryptAndVerify(void *dst, size_t dst_size, const void *signature, const void *modulus, const void *exponent, size_t exponent_size, const void *label_hash, size_t *out_size);
 
 #endif /* __RSA_H__ */

source/tik.c

@@ -21,6 +21,7 @@
 
 #include "utils.h"
 #include "tik.h"
+#include "cert.h"
 #include "save.h"
 #include "es.h"
 #include "keys.h"

todo.txt

@@ -2,6 +2,7 @@ todo:
     
     hfs0: filelist generation methods
     
+    tik: make sure the common crypto cert is available when fakesigning a ticket
     tik: automatically dump tickets to the SD card?
     tik: use dumped tickets when the original ones can't be found in the ES savefile?