diff options
Diffstat (limited to 'src/core/hw/aes')
| -rw-r--r-- | src/core/hw/aes/arithmetic128.cpp | 47 | ||||
| -rw-r--r-- | src/core/hw/aes/arithmetic128.h | 17 | ||||
| -rw-r--r-- | src/core/hw/aes/ccm.cpp | 95 | ||||
| -rw-r--r-- | src/core/hw/aes/ccm.h | 40 | ||||
| -rw-r--r-- | src/core/hw/aes/key.cpp | 173 | ||||
| -rw-r--r-- | src/core/hw/aes/key.h | 35 | 
6 files changed, 407 insertions, 0 deletions
| diff --git a/src/core/hw/aes/arithmetic128.cpp b/src/core/hw/aes/arithmetic128.cpp new file mode 100644 index 000000000..55b954a52 --- /dev/null +++ b/src/core/hw/aes/arithmetic128.cpp @@ -0,0 +1,47 @@ +// Copyright 2017 Citra Emulator Project +// Licensed under GPLv2 or any later version +// Refer to the license.txt file included. + +#include <algorithm> +#include <functional> +#include "core/hw/aes/arithmetic128.h" + +namespace HW { +namespace AES { + +AESKey Lrot128(const AESKey& in, u32 rot) { +    AESKey out; +    rot %= 128; +    const u32 byte_shift = rot / 8; +    const u32 bit_shift = rot % 8; + +    for (u32 i = 0; i < 16; i++) { +        const u32 wrap_index_a = (i + byte_shift) % 16; +        const u32 wrap_index_b = (i + byte_shift + 1) % 16; +        out[i] = ((in[wrap_index_a] << bit_shift) | (in[wrap_index_b] >> (8 - bit_shift))) & 0xFF; +    } +    return out; +} + +AESKey Add128(const AESKey& a, const AESKey& b) { +    AESKey out; +    u32 carry = 0; +    u32 sum = 0; + +    for (int i = 15; i >= 0; i--) { +        sum = a[i] + b[i] + carry; +        carry = sum >> 8; +        out[i] = static_cast<u8>(sum & 0xff); +    } + +    return out; +} + +AESKey Xor128(const AESKey& a, const AESKey& b) { +    AESKey out; +    std::transform(a.cbegin(), a.cend(), b.cbegin(), out.begin(), std::bit_xor<>()); +    return out; +} + +} // namespace AES +} // namespace HW diff --git a/src/core/hw/aes/arithmetic128.h b/src/core/hw/aes/arithmetic128.h new file mode 100644 index 000000000..d670e2ce2 --- /dev/null +++ b/src/core/hw/aes/arithmetic128.h @@ -0,0 +1,17 @@ +// Copyright 2017 Citra Emulator Project +// Licensed under GPLv2 or any later version +// Refer to the license.txt file included. + +#pragma once + +#include "common/common_types.h" +#include "core/hw/aes/key.h" + +namespace HW { +namespace AES { +AESKey Lrot128(const AESKey& in, u32 rot); +AESKey Add128(const AESKey& a, const AESKey& b); +AESKey Xor128(const AESKey& a, const AESKey& b); + +} // namspace AES +} // namespace HW diff --git a/src/core/hw/aes/ccm.cpp b/src/core/hw/aes/ccm.cpp new file mode 100644 index 000000000..dc7035ab6 --- /dev/null +++ b/src/core/hw/aes/ccm.cpp @@ -0,0 +1,95 @@ +// Copyright 2017 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/ccm.h> +#include <cryptopp/cryptlib.h> +#include <cryptopp/filters.h> +#include "common/alignment.h" +#include "common/logging/log.h" +#include "core/hw/aes/ccm.h" +#include "core/hw/aes/key.h" + +namespace HW { +namespace AES { + +namespace { + +// 3DS uses a non-standard AES-CCM algorithm, so we need to derive a sub class from the standard one +// and override with the non-standard part. +using CryptoPP::lword; +using CryptoPP::AES; +using CryptoPP::CCM_Final; +using CryptoPP::CCM_Base; +template <bool T_IsEncryption> +class CCM_3DSVariant_Final : public CCM_Final<AES, CCM_MAC_SIZE, T_IsEncryption> { +public: +    void UncheckedSpecifyDataLengths(lword header_length, lword message_length, +                                     lword footer_length) override { +        // 3DS uses the aligned size to generate B0 for authentication, instead of the original size +        lword aligned_message_length = Common::AlignUp(message_length, AES_BLOCK_SIZE); +        CCM_Base::UncheckedSpecifyDataLengths(header_length, aligned_message_length, footer_length); +        CCM_Base::m_messageLength = message_length; // restore the actual message size +    } +}; + +class CCM_3DSVariant { +public: +    using Encryption = CCM_3DSVariant_Final<true>; +    using Decryption = CCM_3DSVariant_Final<false>; +}; + +} // namespace + +std::vector<u8> EncryptSignCCM(const std::vector<u8>& pdata, const CCMNonce& nonce, +                               size_t slot_id) { +    if (!IsNormalKeyAvailable(slot_id)) { +        LOG_ERROR(HW_AES, "Key slot %d not available. Will use zero key.", slot_id); +    } +    const AESKey normal = GetNormalKey(slot_id); +    std::vector<u8> cipher(pdata.size() + CCM_MAC_SIZE); + +    try { +        CCM_3DSVariant::Encryption e; +        e.SetKeyWithIV(normal.data(), AES_BLOCK_SIZE, nonce.data(), CCM_NONCE_SIZE); +        e.SpecifyDataLengths(0, pdata.size(), 0); +        CryptoPP::ArraySource as(pdata.data(), pdata.size(), true, +                                 new CryptoPP::AuthenticatedEncryptionFilter( +                                     e, new CryptoPP::ArraySink(cipher.data(), cipher.size()))); +    } catch (const CryptoPP::Exception& e) { +        LOG_ERROR(HW_AES, "FAILED with: %s", e.what()); +    } +    return cipher; +} + +std::vector<u8> DecryptVerifyCCM(const std::vector<u8>& cipher, const CCMNonce& nonce, +                                 size_t slot_id) { +    if (!IsNormalKeyAvailable(slot_id)) { +        LOG_ERROR(HW_AES, "Key slot %d not available. Will use zero key.", slot_id); +    } +    const AESKey normal = GetNormalKey(slot_id); +    const std::size_t pdata_size = cipher.size() - CCM_MAC_SIZE; +    std::vector<u8> pdata(pdata_size); + +    try { +        CCM_3DSVariant::Decryption d; +        d.SetKeyWithIV(normal.data(), AES_BLOCK_SIZE, nonce.data(), CCM_NONCE_SIZE); +        d.SpecifyDataLengths(0, pdata_size, 0); +        CryptoPP::AuthenticatedDecryptionFilter df( +            d, new CryptoPP::ArraySink(pdata.data(), pdata_size)); +        CryptoPP::ArraySource as(cipher.data(), cipher.size(), true, new CryptoPP::Redirector(df)); +        if (!df.GetLastResult()) { +            LOG_ERROR(HW_AES, "FAILED"); +            return {}; +        } +    } catch (const CryptoPP::Exception& e) { +        LOG_ERROR(HW_AES, "FAILED with: %s", e.what()); +        return {}; +    } +    return pdata; +} + +} // namespace AES +} // namespace HW diff --git a/src/core/hw/aes/ccm.h b/src/core/hw/aes/ccm.h new file mode 100644 index 000000000..bf4146e80 --- /dev/null +++ b/src/core/hw/aes/ccm.h @@ -0,0 +1,40 @@ +// Copyright 2017 Citra Emulator Project +// Licensed under GPLv2 or any later version +// Refer to the license.txt file included. + +#pragma once + +#include <array> +#include <cstddef> +#include <vector> +#include "common/common_types.h" + +namespace HW { +namespace AES { + +constexpr size_t CCM_NONCE_SIZE = 12; +constexpr size_t CCM_MAC_SIZE = 16; + +using CCMNonce = std::array<u8, CCM_NONCE_SIZE>; + +/** + * Encrypts and adds a MAC to the given data using AES-CCM algorithm. + * @param pdata The plain text data to encrypt + * @param nonce The nonce data to use for encryption + * @param slot_id The slot ID of the key to use for encryption + * @returns a vector of u8 containing the encrypted data with MAC at the end + */ +std::vector<u8> EncryptSignCCM(const std::vector<u8>& pdata, const CCMNonce& nonce, size_t slot_id); + +/** + * Decrypts and verify the MAC of the given data using AES-CCM algorithm. + * @param cipher The cipher text data to decrypt, with MAC at the end to verify + * @param nonce The nonce data to use for decryption + * @param slot_id The slot ID of the key to use for decryption + * @returns a vector of u8 containing the decrypted data; an empty vector if the verification fails + */ +std::vector<u8> DecryptVerifyCCM(const std::vector<u8>& cipher, const CCMNonce& nonce, +                                 size_t slot_id); + +} // namespace AES +} // namespace HW diff --git a/src/core/hw/aes/key.cpp b/src/core/hw/aes/key.cpp new file mode 100644 index 000000000..4e8a8a59a --- /dev/null +++ b/src/core/hw/aes/key.cpp @@ -0,0 +1,173 @@ +// Copyright 2017 Citra Emulator Project +// Licensed under GPLv2 or any later version +// Refer to the license.txt file included. + +#include <algorithm> +#include <exception> +#include <sstream> +#include <boost/optional.hpp> +#include "common/common_paths.h" +#include "common/file_util.h" +#include "common/logging/log.h" +#include "common/string_util.h" +#include "core/hw/aes/arithmetic128.h" +#include "core/hw/aes/key.h" + +namespace HW { +namespace AES { + +namespace { + +boost::optional<AESKey> generator_constant; + +struct KeySlot { +    boost::optional<AESKey> x; +    boost::optional<AESKey> y; +    boost::optional<AESKey> normal; + +    void SetKeyX(const AESKey& key) { +        x = key; +        if (y && generator_constant) { +            GenerateNormalKey(); +        } +    } + +    void SetKeyY(const AESKey& key) { +        y = key; +        if (x && generator_constant) { +            GenerateNormalKey(); +        } +    } + +    void SetNormalKey(const AESKey& key) { +        normal = key; +    } + +    void GenerateNormalKey() { +        normal = Lrot128(Add128(Xor128(Lrot128(*x, 2), *y), *generator_constant), 87); +    } + +    void Clear() { +        x.reset(); +        y.reset(); +        normal.reset(); +    } +}; + +std::array<KeySlot, KeySlotID::MaxKeySlotID> key_slots; + +void ClearAllKeys() { +    for (KeySlot& slot : key_slots) { +        slot.Clear(); +    } +    generator_constant.reset(); +} + +AESKey HexToKey(const std::string& hex) { +    if (hex.size() < 32) { +        throw std::invalid_argument("hex string is too short"); +    } + +    AESKey key; +    for (size_t i = 0; i < key.size(); ++i) { +        key[i] = static_cast<u8>(std::stoi(hex.substr(i * 2, 2), 0, 16)); +    } + +    return key; +} + +void LoadPresetKeys() { +    const std::string filepath = FileUtil::GetUserPath(D_SYSDATA_IDX) + AES_KEYS; +    FileUtil::CreateFullPath(filepath); // Create path if not already created +    std::ifstream file; +    OpenFStream(file, filepath, std::ios_base::in); +    if (!file) { +        return; +    } + +    while (!file.eof()) { +        std::string line; +        std::getline(file, line); +        std::vector<std::string> parts; +        Common::SplitString(line, '=', parts); +        if (parts.size() != 2) { +            LOG_ERROR(HW_AES, "Failed to parse %s", line.c_str()); +            continue; +        } + +        const std::string& name = parts[0]; +        AESKey key; +        try { +            key = HexToKey(parts[1]); +        } catch (const std::logic_error& e) { +            LOG_ERROR(HW_AES, "Invalid key %s: %s", parts[1].c_str(), e.what()); +            continue; +        } + +        if (name == "generator") { +            generator_constant = key; +            continue; +        } + +        size_t slot_id; +        char key_type; +        if (std::sscanf(name.c_str(), "slot0x%zXKey%c", &slot_id, &key_type) != 2) { +            LOG_ERROR(HW_AES, "Invalid key name %s", name.c_str()); +            continue; +        } + +        if (slot_id >= MaxKeySlotID) { +            LOG_ERROR(HW_AES, "Out of range slot ID 0x%zX", slot_id); +            continue; +        } + +        switch (key_type) { +        case 'X': +            key_slots.at(slot_id).SetKeyX(key); +            break; +        case 'Y': +            key_slots.at(slot_id).SetKeyY(key); +            break; +        case 'N': +            key_slots.at(slot_id).SetNormalKey(key); +            break; +        default: +            LOG_ERROR(HW_AES, "Invalid key type %c", key_type); +            break; +        } +    } +} + +} // namespace + +void InitKeys() { +    ClearAllKeys(); +    LoadPresetKeys(); +} + +void SetGeneratorConstant(const AESKey& key) { +    generator_constant = key; +} + +void SetKeyX(size_t slot_id, const AESKey& key) { +    key_slots.at(slot_id).SetKeyX(key); +} + +void SetKeyY(size_t slot_id, const AESKey& key) { +    key_slots.at(slot_id).SetKeyY(key); +} + +void SetNormalKey(size_t slot_id, const AESKey& key) { +    key_slots.at(slot_id).SetNormalKey(key); +} + +bool IsNormalKeyAvailable(size_t slot_id) { +    return key_slots.at(slot_id).normal.is_initialized(); +} + +AESKey GetNormalKey(size_t slot_id) { +    return key_slots.at(slot_id).normal.value_or(AESKey{}); +} + +} // namespace AES +} // namespace HW diff --git a/src/core/hw/aes/key.h b/src/core/hw/aes/key.h new file mode 100644 index 000000000..b01d04f13 --- /dev/null +++ b/src/core/hw/aes/key.h @@ -0,0 +1,35 @@ +// Copyright 2017 Citra Emulator Project +// Licensed under GPLv2 or any later version +// Refer to the license.txt file included. + +#pragma once + +#include <array> +#include <cstddef> +#include "common/common_types.h" + +namespace HW { +namespace AES { + +enum KeySlotID : size_t { +    APTWrap = 0x31, + +    MaxKeySlotID = 0x40, +}; + +constexpr size_t AES_BLOCK_SIZE = 16; + +using AESKey = std::array<u8, AES_BLOCK_SIZE>; + +void InitKeys(); + +void SetGeneratorConstant(const AESKey& key); +void SetKeyX(size_t slot_id, const AESKey& key); +void SetKeyY(size_t slot_id, const AESKey& key); +void SetNormalKey(size_t slot_id, const AESKey& key); + +bool IsNormalKeyAvailable(size_t slot_id); +AESKey GetNormalKey(size_t slot_id); + +} // namspace AES +} // namespace HW | 
