Elpisdev_unsegaREBORN/src/crypto.c

#include "crypto.h"
#include "aes.h"
#include "common.h"

const uint8_t NTFS_HEADER[16] = {
    0xeb, 0x52, 0x90, 0x4e, 0x54, 0x46, 0x53, 0x20,
    0x20, 0x20, 0x20, 0x00, 0x10, 0x01, 0x00, 0x00
};
const uint8_t EXFAT_HEADER[16] = {
    0xeb, 0x76, 0x90, 0x45, 0x58, 0x46, 0x41, 0x54,
    0x20, 0x20, 0x20, 0x00, 0x00, 0x00, 0x00, 0x00
};
const uint8_t OPTION_KEY[16] = {
    0x5c, 0x84, 0xa9, 0xe7, 0x26, 0xea, 0xa5, 0xdd,
    0x35, 0x1f, 0x2b, 0x07, 0x50, 0xc2, 0x36, 0x97
};
const uint8_t APM3_SEED[96] = {
    0xC7, 0x3C, 0xDD, 0xBF, 0x7A, 0xFB, 0x0E, 0xBC, 0xE6, 0xDE, 0xD4, 0xD9, 0xB3, 0xDF, 0x3B, 0x03,
    0x3F, 0xE1, 0x40, 0xE4, 0xF4, 0xFF, 0x96, 0xC5, 0x79, 0x90, 0x8B, 0x5B, 0x69, 0x6A, 0xBE, 0xEE,
    0x32, 0x6C, 0x5E, 0xEA, 0x47, 0xC0, 0xA3, 0x40, 0x51, 0xDC, 0x55, 0xBF, 0x8C, 0x2A, 0x80, 0x7B,
    0xE4, 0xC6, 0xE3, 0xEF, 0x2F, 0x15, 0x30, 0x84, 0x69, 0x3C, 0xE2, 0xD2, 0x1E, 0xF1, 0xBB, 0x13,
    0xDC, 0xC9, 0x6D, 0x31, 0x7C, 0x3F, 0xCC, 0x7A, 0xB9, 0x44, 0x63, 0x6D, 0x65, 0xC2, 0x8B, 0xB8,
    0xE2, 0xF7, 0x74, 0x8D, 0xC6, 0x42, 0x08, 0xA8, 0x73, 0x41, 0x4B, 0x78, 0x7E, 0x3F, 0x18, 0x66
};
const uint8_t APM3_KEY[16] = {
    0x87, 0x3d, 0xf6, 0x32, 0xb9, 0x88, 0xae, 0x14,
    0xaa, 0x9f, 0x73, 0x6b, 0x03, 0xa5, 0x1c, 0x4f
};
const uint8_t APM3_IV[16] = {
    0x35, 0x7d, 0xc1, 0x90, 0x30, 0xd8, 0xe8, 0xd4,
    0x94, 0x1a, 0x7e, 0x6a, 0xce, 0xb9, 0x4e, 0x4c
};
const uint8_t BOOTID_KEY[16] = {
    0x09, 0xCA, 0x5E, 0xFD, 0x30, 0xC9, 0xAA, 0xEF,
    0x38, 0x04, 0xD0, 0xA7, 0xE3, 0xFA, 0x71, 0x20
};
const uint8_t BOOTID_IV[16] = {
    0xB1, 0x55, 0xC2, 0x2C, 0x2E, 0x7F, 0x04, 0x91,
    0xFA, 0x7F, 0x0F, 0xDC, 0x21, 0x7A, 0xFF, 0x90
};

bool key_derive(const char* id, uint8_t out_key[16], uint8_t out_iv[16]) {
    if (!id || strlen(id) < 4) {
        return false;
    }

    uint8_t data[96];
    memcpy(data, APM3_SEED, 96);

    AES_ctx ctx;
    AES_init_ctx_iv(&ctx, APM3_KEY, APM3_IV);
    AES_CBC_decrypt_buffer(&ctx, data, 96);

    uint8_t intermediate[32];
    AES_init_ctx_iv(&ctx, data, data + 16);
    memcpy(intermediate, data + 64, 32);
    AES_CBC_encrypt_buffer(&ctx, intermediate, 32);

    uint8_t pKey[16];
    uint8_t pIv[16];
    memcpy(pKey, intermediate, 16);
    memcpy(pIv, intermediate + 16, 16);

    for (int i = 0; i < 16; i++) {
        pKey[i] ^= (uint8_t)id[i % 4];
        pIv[i] ^= (uint8_t)id[i % 4];
    }

    memcpy(out_key, pKey, 16);
    memcpy(out_iv, pIv, 16);

    return true;
}

void iv_page(uint64_t off, const uint8_t* base, uint8_t* out) {
    __asm__ volatile (
        "movq %[off], %%xmm0\n\t"
        "punpcklqdq %%xmm0, %%xmm0\n\t"
        "movdqu (%[base]), %%xmm1\n\t"
        "pxor %%xmm0, %%xmm1\n\t"
        "movdqu %%xmm1, (%[out])\n\t"
        :
        : [off] "r" (off), [base] "r" (base), [out] "r" (out)
        : "xmm0", "xmm1", "memory"
    );
}

void iv_file(const uint8_t key[16], const uint8_t* hdr, const uint8_t* page, uint8_t out[16]) {
    uint8_t iv[16];
    uint8_t header[16];
    memcpy(header, page, 16);

    iv_page(0, hdr, iv);

    AES_ctx ctx;
    AES_init_ctx_iv(&ctx, key, iv);
    AES_CBC_decrypt_buffer(&ctx, header, 16);

    memcpy(out, header, 16);
}

bool key_game(const char* id, GameKeys* out) {
    if (key_lookup(id, out->key, &out->external)) {
        return true;
    }
    out->external = false;
    return false;
}