[ncatool] Self select NCA header key.

This commit is contained in:
jakcron 2018-03-21 20:31:39 +08:00
parent a44a0257fe
commit 1362bac1cb

View file

@ -13,110 +13,6 @@
const size_t kNcaSectorSize = nx::NcaHeader::kBlockSize;
inline size_t sectorToOffset(size_t sector_index) { return sector_index * kNcaSectorSize; }
void initNcaCtr(u8 ctr[crypto::aes::kAesBlockSize], u32 generation)
{
memset(ctr, 0, crypto::aes::kAesBlockSize);
for (size_t i = 0; i < 4; i++)
{
ctr[7 - i] = (generation >> i * 8) & 0xff;
}
}
void hexDump(const u8* data, size_t len)
{
for (size_t i = 0; i < len; i++)
{
printf("%02X", data[i]);
}
}
void xorData(const u8* a, const u8* b, u8* out, size_t len)
{
for (size_t i = 0; i < len; i++)
{
out[i] = a[i] ^ b[i];
}
}
void decryptNcaHeader(byte_t header[0xc00], const u8* key1, const u8* key2)
{
byte_t tweak[crypto::aes::kAesBlockSize];
// decrypt main header
byte_t raw_hdr[kNcaSectorSize];
nx::NcaHeader hdr;
crypto::aes::AesXtsMakeTweak(tweak, 1);
crypto::aes::AesXtsDecryptSector(header + sectorToOffset(1), kNcaSectorSize, key1, key2, tweak, raw_hdr);
hdr.importBinary(raw_hdr, kNcaSectorSize);
// decrypt whole header
for (size_t i = 0; i < 6; i++)
{
crypto::aes::AesXtsMakeTweak(tweak, (i > 1 && hdr.getFormatVersion() == nx::NcaHeader::NCA2_FORMAT)? 0 : i);
crypto::aes::AesXtsDecryptSector(header + sectorToOffset(i), kNcaSectorSize, key1, key2, tweak, header + sectorToOffset(i));
}
}
void decryptNcaSectorXts(const fnd::MemoryBlob& nca, u8 out[kNcaSectorSize], size_t sector, const u8* key1, const u8* key2)
{
u8 tweak[crypto::aes::kAesBlockSize];
crypto::aes::AesXtsMakeTweak(tweak, sector);
crypto::aes::AesXtsDecryptSector(nca.getBytes() + sector*kNcaSectorSize, kNcaSectorSize, key1, key2, tweak, out);
}
void decryptNcaSectorCtr(const fnd::MemoryBlob& nca, u8 out[kNcaSectorSize], size_t sector, const u8* key)
{
u8 ctr[crypto::aes::kAesBlockSize];
initNcaCtr(ctr, 0);
crypto::aes::AesIncrementCounter(ctr, (sector*kNcaSectorSize)/crypto::aes::kAesBlockSize, ctr);
crypto::aes::AesCtr(nca.getBytes() + sector*kNcaSectorSize, kNcaSectorSize, key, ctr, out);
}
void dumpNcaSector(u8 out[kNcaSectorSize])
{
for (size_t j = 0; j < kNcaSectorSize / crypto::aes::kAesBlockSize; j++)
{
hexDump(out + j * crypto::aes::kAesBlockSize, crypto::aes::kAesBlockSize);
printf("\n");
}
}
void dumpHxdStyleSector(u8* out, size_t len)
{
// iterate over 0x10 blocks
for (size_t i = 0; i < (len / crypto::aes::kAesBlockSize); i++)
{
// for block i print each byte
for (size_t j = 0; j < crypto::aes::kAesBlockSize; j++)
{
printf("%02X ", out[i*crypto::aes::kAesBlockSize + j]);
}
printf(" ");
for (size_t j = 0; j < crypto::aes::kAesBlockSize; j++)
{
printf("%c", isalnum(out[i*crypto::aes::kAesBlockSize + j]) ? out[i*crypto::aes::kAesBlockSize + j] : '.');
}
printf("\n");
}
/*
for (size_t i = 0; i < len % crypto::aes::kAesBlockSize; i++)
{
printf("%02X ", out[(len / crypto::aes::kAesBlockSize)*crypto::aes::kAesBlockSize + i]);
}
for (size_t i = 0; i < crypto::aes::kAesBlockSize - (len % crypto::aes::kAesBlockSize); i++)
{
printf(" ");
}
for (size_t i = 0; i < len % crypto::aes::kAesBlockSize; i++)
{
printf("%c", out[(len / crypto::aes::kAesBlockSize)*crypto::aes::kAesBlockSize + i]);
}
*/
}
std::string kFormatVersionStr[]
{
"NCA2",
@ -177,6 +73,20 @@ enum EncryptionType
CRYPT_BKTR
};
static const byte_t kNcaMagic[2][4] = {{'N','C','A','2'}, {'N','C','A','3'}};
enum KeysetType
{
KEYSET_DEV,
KEYSET_PROD
};
static const byte_t* kNcaHeaderKey[2][2] =
{
{ crypto::aes::nx::dev::nca_header_key[0], crypto::aes::nx::dev::nca_header_key[1] },
{ crypto::aes::nx::prod::nca_header_key[0], crypto::aes::nx::prod::nca_header_key[1] }
};
#pragma pack(push,1)
struct sNcaFsHeader
{
@ -188,7 +98,140 @@ struct sNcaFsHeader
};
#pragma pack(pop)
inline size_t sectorToOffset(size_t sector_index) { return sector_index * kNcaSectorSize; }
void initNcaCtr(u8 ctr[crypto::aes::kAesBlockSize], u32 generation)
{
memset(ctr, 0, crypto::aes::kAesBlockSize);
for (size_t i = 0; i < 4; i++)
{
ctr[7 - i] = (generation >> i * 8) & 0xff;
}
}
void hexDump(const u8* data, size_t len)
{
for (size_t i = 0; i < len; i++)
{
printf("%02X", data[i]);
}
}
void xorData(const u8* a, const u8* b, u8* out, size_t len)
{
for (size_t i = 0; i < len; i++)
{
out[i] = a[i] ^ b[i];
}
}
void decryptNcaHeader(byte_t header[0xc00], const byte_t* key[2])
{
byte_t tweak[crypto::aes::kAesBlockSize];
// decrypt main header
byte_t raw_hdr[kNcaSectorSize];
nx::NcaHeader hdr;
crypto::aes::AesXtsMakeTweak(tweak, 1);
crypto::aes::AesXtsDecryptSector(header + sectorToOffset(1), kNcaSectorSize, key[0], key[1], tweak, raw_hdr);
hdr.importBinary(raw_hdr, kNcaSectorSize);
// decrypt whole header
for (size_t i = 0; i < 6; i++)
{
crypto::aes::AesXtsMakeTweak(tweak, (i > 1 && hdr.getFormatVersion() == nx::NcaHeader::NCA2_FORMAT)? 0 : i);
crypto::aes::AesXtsDecryptSector(header + sectorToOffset(i), kNcaSectorSize, key[0], key[1], tweak, header + sectorToOffset(i));
}
}
void decryptNcaSectorXts(const fnd::MemoryBlob& nca, u8 out[kNcaSectorSize], size_t sector, const byte_t* key[2])
{
u8 tweak[crypto::aes::kAesBlockSize];
crypto::aes::AesXtsMakeTweak(tweak, sector);
crypto::aes::AesXtsDecryptSector(nca.getBytes() + sectorToOffset(sector), kNcaSectorSize, key[0], key[1], tweak, out);
}
void decryptNcaSectorCtr(const fnd::MemoryBlob& nca, u8 out[kNcaSectorSize], size_t sector, const u8* key)
{
u8 ctr[crypto::aes::kAesBlockSize];
initNcaCtr(ctr, 0);
crypto::aes::AesIncrementCounter(ctr, (sector*kNcaSectorSize)/crypto::aes::kAesBlockSize, ctr);
crypto::aes::AesCtr(nca.getBytes() + sector*kNcaSectorSize, kNcaSectorSize, key, ctr, out);
}
void dumpNcaSector(u8 out[kNcaSectorSize])
{
for (size_t j = 0; j < kNcaSectorSize / crypto::aes::kAesBlockSize; j++)
{
hexDump(out + j * crypto::aes::kAesBlockSize, crypto::aes::kAesBlockSize);
printf("\n");
}
}
void dumpHxdStyleSector(u8* out, size_t len)
{
// iterate over 0x10 blocks
for (size_t i = 0; i < (len / crypto::aes::kAesBlockSize); i++)
{
// for block i print each byte
for (size_t j = 0; j < crypto::aes::kAesBlockSize; j++)
{
printf("%02X ", out[i*crypto::aes::kAesBlockSize + j]);
}
printf(" ");
for (size_t j = 0; j < crypto::aes::kAesBlockSize; j++)
{
printf("%c", isalnum(out[i*crypto::aes::kAesBlockSize + j]) ? out[i*crypto::aes::kAesBlockSize + j] : '.');
}
printf("\n");
}
/*
for (size_t i = 0; i < len % crypto::aes::kAesBlockSize; i++)
{
printf("%02X ", out[(len / crypto::aes::kAesBlockSize)*crypto::aes::kAesBlockSize + i]);
}
for (size_t i = 0; i < crypto::aes::kAesBlockSize - (len % crypto::aes::kAesBlockSize); i++)
{
printf(" ");
}
for (size_t i = 0; i < len % crypto::aes::kAesBlockSize; i++)
{
printf("%c", out[(len / crypto::aes::kAesBlockSize)*crypto::aes::kAesBlockSize + i]);
}
*/
}
bool testNcaHeaderKey(const byte_t* header_src, const byte_t* key[2])
{
bool validKey = false;
byte_t header_dec[kNcaSectorSize];
u8 tweak[crypto::aes::kAesBlockSize];
// try key
crypto::aes::AesXtsMakeTweak(tweak, 1);
crypto::aes::AesXtsDecryptSector(header_src + sectorToOffset(1), kNcaSectorSize, key[0], key[1], tweak, header_dec);
if (memcmp(header_dec, kNcaMagic[0], 4) == 0 || memcmp(header_dec, kNcaMagic[1], 4) == 0)
{
validKey = true;
}
return validKey;
}
KeysetType getKeysetFromNcaHeader(const byte_t* header_src)
{
for (int i = 0; i < 2; i++)
{
if (testNcaHeaderKey(header_src, kNcaHeaderKey[i]) == true)
{
return (KeysetType)i;
}
}
throw fnd::Exception("Failed to determine NCA header key");
}
int main(int argc, char** argv)
{
@ -203,10 +246,10 @@ int main(int argc, char** argv)
fnd::MemoryBlob nca;
fnd::io::readFile(argv[1], nca);
decryptNcaHeader(nca.getBytes(), crypto::aes::nx::dev::nca_header_key[0], crypto::aes::nx::dev::nca_header_key[1]);
//dumpHxdStyleSector(nca.getBytes(), 0xc00);
KeysetType keyset = getKeysetFromNcaHeader(nca.getBytes());
//u8 sector[kNcaSectorSize];
decryptNcaHeader(nca.getBytes(), kNcaHeaderKey[keyset]);
//dumpHxdStyleSector(nca.getBytes(), 0xc00);
// nca test
if (argc == 2 || argc == 3)
@ -259,7 +302,7 @@ int main(int argc, char** argv)
crypto::sha::Sha256(nca.getBytes() + sectorToOffset(sector_index), kNcaSectorSize, hash);
if (section.hash.compare(hash) == false)
{
//throw fnd::Exception("ncatool", "NcaFsHeader has bad sha256 hash");
throw fnd::Exception("ncatool", "NcaFsHeader has bad sha256 hash");
}
const sNcaFsHeader* fsHdr = (const sNcaFsHeader*)(nca.getBytes() + sectorToOffset(sector_index));