Sealedkey / pfsSKKey

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This key can be found on different places and will be used for eg. SaveGame or Trophy Data decryption and encryption.

Paths[edit]

Kind Path
Trophys /user/home/user Id/trophy/data/sce_trop/sealedkey
SaveGames /user/home/user Id/title Id/save data directory/sce_sys/

Structure[edit]

- size always 96 bytes

From To Description
00 07 MAGIC ("pfsSKKey") (?playstation file system sealed key key?)
08 0F Category (game=1 or version ?)
10 1F IV (16 bytes)
20 3F Encrypted key (32 bytes)
40 5F SHA-256 (32 bytes)

C

 typedef struct sealedkey_t {
     const unsigned char MAGIC[8];
     const unsigned char CAT[8];
     const unsigned char IV[16];
     const unsigned char KEY[32];
     const unsigned char SHA256[32];
 } PfsSKKey;

CSharp

 protected internal struct sealedkey {
     internal static byte[] MAGIC = new byte[8];
     internal static byte[] CAT = new byte[8];
     internal static byte[] IV = new byte[16];
     internal static byte[] KEY = new byte[32];
     internal static byte[] SHA256 = new byte[32];
 }

Note: You can't use a const byte[] defination in C#. It need to be a static byte[].

De/En -Crypting[edit]

Can be decrypted by friendly asking the OS to do it for you. You will need kernel rights to be able to ask the PS4 for it.

 /* Decryption */ 
 #define foreach(item, array) \
     for (int keep = 1, \
              count = 0, \
              size = sizeof(array) / sizeof*(array); \
          keep && count != size; \
          keep = !keep, count++) \
         for (item = (array) + count; keep; keep = !keep)
 
 typedef unsigned char byte;              /* byte defination for c/c++ */
 byte PFSK_IDENT[8] = "pfsSKKey";
 byte VERSION[8] = "\x01\x00\x00\x00\x00\x00\x00\x00"
 const char USER1 = "10000000";
 const char usb0 = "/mnt/usb0/";
 const char usb1 = "/mnt/usb1/";
 const char pfs = "dec_pfsSK.Key";
 const char home = "/user/home/";
 const char tropkey = "/trophy/data/sce_trop/sealedkey";
 char usb_error = "[-] ERROR: Can't access usb0 nor usb1!\n[-] Will return now to caller.\n"
 char usb0path[(strlen(usb0) + strlen(pfs))];
 char usb1path[strlen(usb0path)];
 
 /* Get's the encrypted sealed key based on user id */
 int get_pfsSKKey(byte *buffer, const char *userID, char path) {
     char toOpen[(strlen(home) + strlen(userID) + strlen(path))];
 
     sprintf(toOpen, home, userID, path)
 
     FILE *pfskey = fopen(toOpen, "r"); 
 
     if (!pfskey) return NULL;
 
     fread(buffer, 96, 1, pfskey);
     fclose(pfskey);
     return 1;
 }
 
 /* Dump the sealedkey. Send over tcp and save to file */
 int dumpDecryptedSealedKey(int to) {
     if (to < 0 || to > 1) return -2;
 
     /* First load the sealedkey into a buffer */
     PfsSKKEy enc;
     if (!get_pfsSKKey(&enc, USER1, tropkey)) {
         printf("[-] Can not load the sealed key!\n");
         return -1;
     }
 
     /* Let's check the pfsSKKEy */
     if (enc->MAGIC == PFSK_IDENT && enc->CAT == VERSION) {
         printf("[+] Magic and version ok!\n[+] sk IV = ");
         foreach(byte *val, &enc->IV) printf("%02X", *val);
 
         printf("\n[+] sk KEY = ");
         foreach(byte *val, enc->KEY) printf("%02X", *val);
 
         printf("\n[+] sk Key-SHA256 = ");
         foreach(byte *val, sk->SHA256) printf("%02X", *val);
         printf("\n");
 
     }
     else return -4;
 
     /* Now decrypt it */
     byte dec[16];
 
     int i;
     if (!(i = kernel.sceSblSsDecryptSealedKey(&enc, &dec))) {
         printf("[-] Error!\n[-] sceSblSsDecryptSealedKey returned %d\n", i);
         return -1;
     }
     printf("[+] sceSblSsDecryptSealedKey returned %d\n", i);
 
     if (!to) { /* Print it out */
         printf("[+] Your decrypted sealedkey = ");
 
         foreach(byte *val, &dec) printf("%02X", *val);
 
         printf("\n");
         return 1;
     }
     else { /* Saving to file */
         printf("[+] Will try to save to file...");
 
         sprintf(usb0path, usb0, pfs);
         sprintf(usb1path, usb1, pfs);
 
         FILE *dump = fopen(usb0path, "w");
 
         if (!dump) {
             dump = fopen(usb1path, "w");
             if (!dump) {
                 printf("fail!\n%s", usb_error);
                 return -3;
             }
         }
 
         fwrite(&dec, 16, 1, dump);
         printf("done!\n");
         fclose(dump);
         return 1;
     }
 }