i2pd/Garlic.h
2014-07-29 21:56:03 -04:00

136 lines
3.7 KiB
C++

#ifndef GARLIC_H__
#define GARLIC_H__
#include <inttypes.h>
#include <map>
#include <list>
#include <string>
#include <thread>
#include <cryptopp/osrng.h>
#include "aes.h"
#include "I2NPProtocol.h"
#include "LeaseSet.h"
#include "Tunnel.h"
#include "Queue.h"
namespace i2p
{
namespace garlic
{
enum GarlicDeliveryType
{
eGarlicDeliveryTypeLocal = 0,
eGarlicDeliveryTypeDestination = 1,
eGarlicDeliveryTypeRouter = 2,
eGarlicDeliveryTypeTunnel = 3
};
#pragma pack(1)
struct ElGamalBlock
{
uint8_t sessionKey[32];
uint8_t preIV[32];
uint8_t padding[158];
};
#pragma pack()
const int TAGS_EXPIRATION_TIMEOUT = 900; // 15 minutes
typedef i2p::data::Tag<32> SessionTag;
class GarlicRoutingSession
{
public:
GarlicRoutingSession (const i2p::data::RoutingDestination * destination, int numTags);
GarlicRoutingSession (const uint8_t * sessionKey, const SessionTag& sessionTag); // one time encryption
~GarlicRoutingSession ();
I2NPMessage * WrapSingleMessage (I2NPMessage * msg, I2NPMessage * leaseSet);
int GetNextTag () const { return m_NextTag; };
uint32_t GetFirstMsgID () const { return m_FirstMsgID; };
bool IsAcknowledged () const { return m_IsAcknowledged; };
void SetAcknowledged (bool acknowledged) { m_IsAcknowledged = acknowledged; };
private:
size_t CreateAESBlock (uint8_t * buf, const I2NPMessage * msg, const I2NPMessage * leaseSet);
size_t CreateGarlicPayload (uint8_t * payload, const I2NPMessage * msg, const I2NPMessage * leaseSet);
size_t CreateGarlicClove (uint8_t * buf, const I2NPMessage * msg, bool isDestination);
size_t CreateDeliveryStatusClove (uint8_t * buf, uint32_t msgID);
void GenerateSessionTags ();
private:
const i2p::data::RoutingDestination * m_Destination;
uint8_t m_SessionKey[32];
uint32_t m_FirstMsgID; // first message ID
bool m_IsAcknowledged;
int m_NumTags, m_NextTag;
SessionTag * m_SessionTags; // m_NumTags*32 bytes
uint32_t m_TagsCreationTime; // seconds since epoch
i2p::crypto::CBCEncryption m_Encryption;
CryptoPP::AutoSeededRandomPool m_Rnd;
};
class GarlicRouting
{
class SessionDecryption: public i2p::crypto::CBCDecryption
{
public:
SessionDecryption (): m_TagCount (0) {};
void SetTagCount (int tagCount) { m_TagCount = tagCount; };
void AddTagCount (int tagCount) { m_TagCount += tagCount; };
int GetTagCount () const { return m_TagCount; };
bool UseTag () { m_TagCount--; return m_TagCount > 0; };
private:
int m_TagCount;
};
public:
GarlicRouting ();
~GarlicRouting ();
void Start ();
void Stop ();
void AddSessionKey (const uint8_t * key, const uint8_t * tag); // one tag
void HandleGarlicMessage (I2NPMessage * msg);
void HandleDeliveryStatusMessage (uint8_t * buf, size_t len);
I2NPMessage * WrapSingleMessage (const i2p::data::RoutingDestination& destination, I2NPMessage * msg);
I2NPMessage * WrapMessage (const i2p::data::RoutingDestination& destination,
I2NPMessage * msg, I2NPMessage * leaseSet = nullptr);
private:
void Run ();
void ProcessGarlicMessage (I2NPMessage * msg);
void HandleAESBlock (uint8_t * buf, size_t len, SessionDecryption * decryption);
void HandleGarlicPayload (uint8_t * buf, size_t len);
private:
bool m_IsRunning;
std::thread * m_Thread;
i2p::util::Queue<I2NPMessage> m_Queue;
// outgoing sessions
std::map<i2p::data::IdentHash, GarlicRoutingSession *> m_Sessions;
std::map<uint32_t, GarlicRoutingSession *> m_CreatedSessions; // msgID -> session
// incoming session
// multiple tags refer to one decyption
std::map<SessionTag, SessionDecryption *> m_SessionTags; // tag -> decryption
};
extern GarlicRouting routing;
}
}
#endif