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key_manager: Add base key derivation 

Derives master keys, game encryption keys, and package1/2 keys
This commit is contained in:
Zach Hilman 2018-09-23 21:03:00 -04:00
parent d7398283e3
commit a57aac5772
2 changed files with 220 additions and 4 deletions
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209
src/core/crypto/key_manager.cpp
View File

@ -262,6 +262,28 @@ void KeyManager::AttemptLoadKeyFile(const std::string& dir1, const std::string&
LoadFromFile(dir2 + DIR_SEP + filename, title);
}
bool KeyManager::BaseDeriveNecessary() {
const auto check_key_existence = [this](auto key_type, u64 index1 = 0, u64 index2 = 0) {
return !HasKey(key_type, index1, index2);
};
if (check_key_existence(S256KeyType::Header))
return true;
for (size_t i = 0; i < CURRENT_CRYPTO_REVISION; ++i) {
if (check_key_existence(S128KeyType::Master, i) ||
check_key_existence(S128KeyType::KeyArea, i,
static_cast<u64>(KeyAreaKeyType::Application)) ||
check_key_existence(S128KeyType::KeyArea, i, static_cast<u64>(KeyAreaKeyType::Ocean)) ||
check_key_existence(S128KeyType::KeyArea, i,
static_cast<u64>(KeyAreaKeyType::System)) ||
check_key_existence(S128KeyType::Titlekek, i))
return true;
}
return false;
}
bool KeyManager::HasKey(S128KeyType id, u64 field1, u64 field2) const {
return s128_keys.find({id, field1, field2}) != s128_keys.end();
}
@ -412,6 +434,193 @@ void KeyManager::DeriveSDSeedLazy() {
SetKey(S128KeyType::SDSeed, res.get());
}
static Key128 CalculateCMAC(const u8* source, size_t size, Key128 key) {
Key128 out{};
mbedtls_cipher_cmac(mbedtls_cipher_info_from_type(MBEDTLS_CIPHER_AES_128_ECB), key.data(), 0x80,
source, size, out.data());
return out;
}
void KeyManager::DeriveBase() {
if (!BaseDeriveNecessary())
return;
if (!HasKey(S128KeyType::SecureBoot) || !HasKey(S128KeyType::TSEC))
return;
const auto has_bis = [this](u64 id) {
return HasKey(S128KeyType::BIS, id, static_cast<u64>(BISKeyType::Crypto)) &&
HasKey(S128KeyType::BIS, id, static_cast<u64>(BISKeyType::Tweak));
};
const auto copy_bis = [this](u64 id_from, u64 id_to) {
SetKey(S128KeyType::BIS,
GetKey(S128KeyType::BIS, id_from, static_cast<u64>(BISKeyType::Crypto)), id_to,
static_cast<u64>(BISKeyType::Crypto));
SetKey(S128KeyType::BIS,
GetKey(S128KeyType::BIS, id_from, static_cast<u64>(BISKeyType::Tweak)), id_to,
static_cast<u64>(BISKeyType::Tweak));
};
if (has_bis(2) && !has_bis(3))
copy_bis(2, 3);
else if (has_bis(3) && !has_bis(2))
copy_bis(3, 2);
std::bitset<32> revisions{};
revisions.set();
for (size_t i = 0; i < 32; ++i) {
if (!HasKey(S128KeyType::Source, static_cast<u64>(SourceKeyType::Keyblob), i) ||
encrypted_keyblobs[i] == std::array<u8, 0xB0>{})
revisions.reset(i);
}
if (!revisions.any())
return;
const auto sbk = GetKey(S128KeyType::SecureBoot);
const auto tsec = GetKey(S128KeyType::TSEC);
const auto master_source = GetKey(S128KeyType::Source, static_cast<u64>(SourceKeyType::Master));
const auto kek_generation_source =
GetKey(S128KeyType::Source, static_cast<u64>(SourceKeyType::AESKekGeneration));
const auto key_generation_source =
GetKey(S128KeyType::Source, static_cast<u64>(SourceKeyType::AESKeyGeneration));
for (size_t i = 0; i < 32; ++i) {
if (!revisions[i])
continue;
// Derive keyblob key
const auto key = DeriveKeyblobKey(
sbk, tsec, GetKey(S128KeyType::Source, static_cast<u64>(SourceKeyType::Keyblob), i));
SetKey(S128KeyType::Keyblob, key, i);
// Derive keyblob MAC key
if (!HasKey(S128KeyType::Source, static_cast<u64>(SourceKeyType::KeyblobMAC)))
continue;
const auto mac_source =
GetKey(S128KeyType::Source, static_cast<u64>(SourceKeyType::KeyblobMAC));
AESCipher<Key128> mac_cipher(key, Mode::ECB);
Key128 mac_key{};
mac_cipher.Transcode(mac_source.data(), mac_key.size(), mac_key.data(), Op::Decrypt);
SetKey(S128KeyType::KeyblobMAC, mac_key, i);
Key128 cmac = CalculateCMAC(encrypted_keyblobs[i].data() + 0x10, 0xA0, mac_key);
if (std::memcmp(cmac.data(), encrypted_keyblobs[i].data(), cmac.size()) != 0)
continue;
// Decrypt keyblob
bool has_keyblob = keyblobs[i] != std::array<u8, 0x90>{};
AESCipher<Key128> cipher(key, Mode::CTR);
cipher.SetIV(std::vector<u8>(encrypted_keyblobs[i].data() + 0x10,
encrypted_keyblobs[i].data() + 0x20));
cipher.Transcode(encrypted_keyblobs[i].data() + 0x20, keyblobs[i].size(),
keyblobs[i].data(), Op::Decrypt);
if (!has_keyblob) {
WriteKeyToFile<0x90>(KeyCategory::Console, fmt::format("keyblob_{:02X}", i),
keyblobs[i]);
}
Key128 package1{};
std::memcpy(package1.data(), keyblobs[i].data() + 0x80, sizeof(Key128));
SetKey(S128KeyType::Package1, package1, i);
// Derive master key
if (HasKey(S128KeyType::Source, static_cast<u64>(SourceKeyType::Master))) {
Key128 master_root{};
std::memcpy(master_root.data(), keyblobs[i].data(), sizeof(Key128));
AESCipher<Key128> master_cipher(master_root, Mode::ECB);
Key128 master{};
master_cipher.Transcode(master_source.data(), master_source.size(), master.data(),
Op::Decrypt);
SetKey(S128KeyType::Master, master, i);
}
}
revisions.set();
for (size_t i = 0; i < 32; ++i) {
if (!HasKey(S128KeyType::Master, i))
revisions.reset(i);
}
if (!revisions.any())
return;
for (size_t i = 0; i < 32; ++i) {
if (!revisions[i])
continue;
// Derive general purpose keys
if (HasKey(S128KeyType::Master, i)) {
for (auto kak_type :
{KeyAreaKeyType::Application, KeyAreaKeyType::Ocean, KeyAreaKeyType::System}) {
if (HasKey(S128KeyType::Source, static_cast<u64>(SourceKeyType::KeyAreaKey),
static_cast<u64>(kak_type))) {
const auto source =
GetKey(S128KeyType::Source, static_cast<u64>(SourceKeyType::KeyAreaKey),
static_cast<u64>(kak_type));
const auto kek =
GenerateKeyEncryptionKey(source, GetKey(S128KeyType::Master, i),
kek_generation_source, key_generation_source);
SetKey(S128KeyType::KeyArea, kek, i, static_cast<u64>(kak_type));
}
}
AESCipher<Key128> master_cipher(GetKey(S128KeyType::Master, i), Mode::ECB);
for (auto key_type : {SourceKeyType::Titlekek, SourceKeyType::Package2}) {
if (HasKey(S128KeyType::Source, static_cast<u64>(key_type))) {
Key128 key{};
master_cipher.Transcode(
GetKey(S128KeyType::Source, static_cast<u64>(key_type)).data(), key.size(),
key.data(), Op::Decrypt);
SetKey(key_type == SourceKeyType::Titlekek ? S128KeyType::Titlekek
: S128KeyType::Package2,
key, i);
}
}
}
}
if (HasKey(S128KeyType::Master, 0) &&
HasKey(S128KeyType::Source, static_cast<u64>(SourceKeyType::AESKeyGeneration)) &&
HasKey(S128KeyType::Source, static_cast<u64>(SourceKeyType::AESKekGeneration)) &&
HasKey(S128KeyType::Source, static_cast<u64>(SourceKeyType::HeaderKek)) &&
HasKey(S256KeyType::HeaderSource)) {
const auto header_kek = GenerateKeyEncryptionKey(
GetKey(S128KeyType::Source, static_cast<u64>(SourceKeyType::HeaderKek)),
GetKey(S128KeyType::Master, 0),
GetKey(S128KeyType::Source, static_cast<u64>(SourceKeyType::AESKekGeneration)),
GetKey(S128KeyType::Source, static_cast<u64>(SourceKeyType::AESKeyGeneration)));
SetKey(S128KeyType::HeaderKek, header_kek);
AESCipher<Key128> header_cipher(header_kek, Mode::ECB);
Key256 out = GetKey(S256KeyType::HeaderSource);
header_cipher.Transcode(out.data(), out.size(), out.data(), Op::Decrypt);
SetKey(S256KeyType::Header, out);
}
}
void KeyManager::SetKeyWrapped(S128KeyType id, Key128 key, u64 field1, u64 field2) {
if (key == Key128{})
return;
SetKey(id, key, field1, field2);
}
void KeyManager::SetKeyWrapped(S256KeyType id, Key256 key, u64 field1, u64 field2) {
if (key == Key256{})
return;
SetKey(id, key, field1, field2);
}
const boost::container::flat_map<std::string, KeyIndex<S128KeyType>> KeyManager::s128_file_id = {
{"eticket_rsa_kek", {S128KeyType::ETicketRSAKek, 0, 0}},
{"eticket_rsa_kek_source",

15
src/core/crypto/key_manager.h
View File

@ -138,9 +138,12 @@ public:
// 8*43 and the private file to exist.
void DeriveSDSeedLazy();
bool BaseDeriveNecessary();
void DeriveBase();
private:
boost::container::flat_map<KeyIndex<S128KeyType>, Key128> s128_keys;
boost::container::flat_map<KeyIndex<S256KeyType>, Key256> s256_keys;
std::map<KeyIndex<S128KeyType>, Key128> s128_keys;
std::map<KeyIndex<S256KeyType>, Key256> s256_keys;
std::array<std::array<u8, 0xB0>, 0x20> encrypted_keyblobs{};
std::array<std::array<u8, 0x90>, 0x20> keyblobs{};
@ -148,8 +151,12 @@ private:
void LoadFromFile(const std::string& filename, bool is_title_keys);
void AttemptLoadKeyFile(const std::string& dir1, const std::string& dir2,
const std::string& filename, bool title);
template <std::size_t Size>
void WriteKeyToFile(bool title_key, std::string_view keyname, const std::array<u8, Size>& key);
template <size_t Size>
void WriteKeyToFile(KeyCategory category, std::string_view keyname,
const std::array<u8, Size>& key);
void SetKeyWrapped(S128KeyType id, Key128 key, u64 field1 = 0, u64 field2 = 0);
void SetKeyWrapped(S256KeyType id, Key256 key, u64 field1 = 0, u64 field2 = 0);
static const boost::container::flat_map<std::string, KeyIndex<S128KeyType>> s128_file_id;
static const boost::container::flat_map<std::string, KeyIndex<S256KeyType>> s256_file_id;