citra/src/core/file_sys/ticket.cpp
Ben b01b94d843 FileSys::Ticket::Load: Return error if signature type does not match (#4339)
* FileSys::Ticket::Load: Return error if signature type does not match

* fixup! FileSys::Ticket::Load: Return error if signature type does not match
2018-10-15 11:26:35 -04:00

60 lines
2.1 KiB
C++

// Copyright 2018 Citra Emulator Project
// Licensed under GPLv2 or any later version
// Refer to the license.txt file included.
#include <algorithm>
#include <cryptopp/aes.h>
#include <cryptopp/modes.h>
#include "common/alignment.h"
#include "core/file_sys/cia_common.h"
#include "core/file_sys/ticket.h"
#include "core/hw/aes/key.h"
#include "core/loader/loader.h"
namespace FileSys {
Loader::ResultStatus Ticket::Load(const std::vector<u8> file_data, std::size_t offset) {
std::size_t total_size = static_cast<std::size_t>(file_data.size() - offset);
if (total_size < sizeof(u32))
return Loader::ResultStatus::Error;
std::memcpy(&signature_type, &file_data[offset], sizeof(u32));
// Signature lengths are variable, and the body follows the signature
u32 signature_size = GetSignatureSize(signature_type);
if (signature_size == 0) {
return Loader::ResultStatus::Error;
}
// The ticket body start position is rounded to the nearest 0x40 after the signature
std::size_t body_start = Common::AlignUp(signature_size + sizeof(u32), 0x40);
std::size_t body_end = body_start + sizeof(Body);
if (total_size < body_end)
return Loader::ResultStatus::Error;
// Read signature + ticket body
ticket_signature.resize(signature_size);
memcpy(ticket_signature.data(), &file_data[offset + sizeof(u32)], signature_size);
memcpy(&ticket_body, &file_data[offset + body_start], sizeof(Body));
return Loader::ResultStatus::Success;
}
std::optional<std::array<u8, 16>> Ticket::GetTitleKey() const {
HW::AES::InitKeys();
std::array<u8, 16> ctr{};
std::memcpy(ctr.data(), &ticket_body.title_id, sizeof(u64));
HW::AES::SelectCommonKeyIndex(ticket_body.common_key_index);
if (!HW::AES::IsNormalKeyAvailable(HW::AES::KeySlotID::TicketCommonKey)) {
return {};
}
auto key = HW::AES::GetNormalKey(HW::AES::KeySlotID::TicketCommonKey);
auto title_key = ticket_body.title_key;
CryptoPP::CBC_Mode<CryptoPP::AES>::Decryption{key.data(), key.size(), ctr.data()}.ProcessData(
title_key.data(), title_key.data(), title_key.size());
return title_key;
}
} // namespace FileSys