TeaSpeakLibrary/src/protocol/CryptionHandler.h

#pragma once

#include <array>
#include <string>
#include "Packet.h"
#include <tomcrypt.h>
#undef byte /* the macro byte gets defined by tomcrypt_macros. We have to undefine it */

namespace ts {
    namespace connection {
        class CryptionHandler {
            enum Methode {
	            TEAMSPEAK_3_1,
	            TEAMSPEAK_3
            };
            struct KeyCache {
            	uint16_t generation = 0xFFEF;
            	uint8_t key[16] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
	            uint8_t nonce[16] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
            };
            public:
                CryptionHandler();
                ~CryptionHandler();

                void reset();

		        //TeamSpeak old
		        bool setupSharedSecret(const std::string& alpha, const std::string& beta, ecc_key* publicKey, ecc_key* ownKey, std::string &error);
                bool setupSharedSecret(const std::string& alpha, const std::string& beta, const std::string& sharedKey, std::string &error);

		        //TeamSpeak new
		        bool setupSharedSecretNew(const std::string& alpha, const std::string& beta, const char privateKey[32], const char publicKey[32]);

                bool progressPacketOut(protocol::BasicPacket*, std::string&, bool use_default);
                bool progressPacketIn(protocol::BasicPacket*, std::string&, bool use_default);

                bool verify_encryption(const pipes::buffer_view& data, uint16_t packet_id, uint16_t generation);

                bool block(){ blocked = true; return true; }
                bool unblock(){ blocked = false; return true; }
                bool isBlocked(){ return blocked; }

                bool use_default() { return this->useDefaultChipherKeyNonce; }
            private:
        		static constexpr char default_key[16] = {'c', ':', '\\', 'w', 'i', 'n', 'd', 'o', 'w', 's', '\\', 's', 'y', 's', 't', 'e'}; //c:\windows\syste
                static constexpr char default_nonce[16] = {'m', '\\', 'f', 'i', 'r', 'e', 'w', 'a', 'l', 'l', '3', '2', '.', 'c', 'p', 'l'}; //m\firewall32.cpl
                static constexpr char default_mac[8] = {'T', 'S', '3', 'I', 'N', 'I', 'T', '1'}; //TS3INIT1


                bool decryptPacket(protocol::BasicPacket *, std::string &, bool use_default);
                bool encryptPacket(protocol::BasicPacket *, std::string &, bool use_default);

		        bool generate_key_nonce(bool /* to server */, protocol::PacketType /* type */, uint16_t /* packet id */, uint16_t /* generation */, bool /* use default */, uint8_t(&)[16] /* key */, uint8_t(&)[16] /* nonce */);
                bool generate_key_nonce(protocol::BasicPacket* packet, bool use_default, uint8_t(&)[16] /* key */, uint8_t(&)[16] /* nonce */);


                //The default key and nonce
                bool useDefaultChipherKeyNonce = true;
		        bool blocked = false;

                /* for the old protocol SHA1 length for the new 64 bytes */
                uint8_t iv_struct[64];
                uint8_t iv_struct_length = 0;

		        uint8_t current_mac[8];

		        std::mutex cache_key_lock;
		        std::array<KeyCache, protocol::PACKET_MAX> cache_key_client;
		        std::array<KeyCache, protocol::PACKET_MAX> cache_key_server;

		        static_assert(sizeof(current_mac) == sizeof(default_mac), "invalid mac");
		        static_assert(sizeof(iv_struct) == 64, "invalid iv struct");
        };
    }
}