nstool/programs/ncatool/main.cpp

#include <cstdio>
#include <crypto/aes.h>
#include <fnd/file_io.h>
#include <fnd/memory_blob.h>
#include <nx/NXCrypto.h>
#include <nx/NcaHeader.h>
#include <inttypes.h>

const size_t kNcaSectorSize = 0x200;

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 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.data() + 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.data() + 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");
	}
}

int main(int argc, char** argv)
{
	if (argc < 2)
	{
		printf("usage: ncatool <nca file>\n");
		return 1;
	}

	fnd::MemoryBlob nca;
	fnd::FileIO::ReadFile(argv[1], nca);

	u8 sector[kNcaSectorSize];

	// nca test
	if (argc == 2)
	{
		decryptNcaSectorXts(nca, sector, 1, nx::crypto::aes::nca_header_key[0], nx::crypto::aes::nca_header_key[1]);

		NcaHeader hdr;
		hdr.importBinary(sector);

		printf("NCA Header\n");
		printf("  Size:       0x%" PRIx64 "\n", hdr.getNcaSize());
		printf("  ProgID:     0x%016" PRIx64 "\n", hdr.getProgramId());
		printf("  Unk0:       0x%" PRIx32 "\n", hdr.getUnk());
		printf("  Sections:\n");
		for (size_t i = 0; i < hdr.getSections().size(); i++)
		{
			const NcaHeader::sSection& section = hdr.getSections()[i];
			printf("    %lu:\n", i);
			printf("      Start Blk: %" PRId32 "\n", section.start_blk);
			printf("      End Blk:   %" PRId32 "\n", section.end_blk);
			printf("      Offset:    0x%" PRIx64 "\n", section.offset);
			printf("      Size:      0x%" PRIx64 "\n", section.size);
			printf("      KeyType:   0x%02x\n", section.key_type);
			printf("      Hash:      ");
			hexDump(section.hash.bytes, crypto::sha::kSha256HashLen);
			printf("\n");
		}
		printf("  AES Keys:\n");
		for (size_t i = 0; i < hdr.getAesKeys().size(); i++)
		{
			printf("    %lu: ", i);
			hexDump(hdr.getAesKeys()[i].key, crypto::aes::kAes128KeySize);
			printf("\n");
		}

		
	}

	return 0;
}