i2pd/libi2pd/LeaseSet.h
2018-01-26 14:33:06 -05:00

137 lines
4.6 KiB
C++

#ifndef LEASE_SET_H__
#define LEASE_SET_H__
#include <inttypes.h>
#include <string.h>
#include <vector>
#include <set>
#include <memory>
#include "Identity.h"
#include "Timestamp.h"
namespace i2p
{
namespace tunnel
{
class InboundTunnel;
}
namespace data
{
const int LEASE_ENDDATE_THRESHOLD = 51000; // in milliseconds
struct Lease
{
IdentHash tunnelGateway;
uint32_t tunnelID;
uint64_t endDate; // 0 means invalid
bool isUpdated; // trasient
/* return true if this lease expires within t millisecond + fudge factor */
bool ExpiresWithin( const uint64_t t, const uint64_t fudge = 1000 ) const {
auto expire = i2p::util::GetMillisecondsSinceEpoch ();
if(fudge) expire += rand() % fudge;
if (endDate < expire) return true;
return (endDate - expire) < t;
}
};
struct LeaseCmp
{
bool operator() (std::shared_ptr<const Lease> l1, std::shared_ptr<const Lease> l2) const
{
if (l1->tunnelID != l2->tunnelID)
return l1->tunnelID < l2->tunnelID;
else
return l1->tunnelGateway < l2->tunnelGateway;
};
};
typedef std::function<bool(const Lease & l)> LeaseInspectFunc;
const size_t MAX_LS_BUFFER_SIZE = 3072;
const size_t LEASE_SIZE = 44; // 32 + 4 + 8
const uint8_t MAX_NUM_LEASES = 16;
class LeaseSet: public RoutingDestination
{
public:
LeaseSet (const uint8_t * buf, size_t len, bool storeLeases = true);
~LeaseSet () { delete[] m_Buffer; };
void Update (const uint8_t * buf, size_t len, bool verifySignature = true);
bool IsNewer (const uint8_t * buf, size_t len) const;
void PopulateLeases (); // from buffer
const uint8_t * GetBuffer () const { return m_Buffer; };
size_t GetBufferLen () const { return m_BufferLen; };
bool IsValid () const { return m_IsValid; };
const std::vector<std::shared_ptr<const Lease> > GetNonExpiredLeases (bool withThreshold = true) const;
const std::vector<std::shared_ptr<const Lease> > GetNonExpiredLeasesExcluding (LeaseInspectFunc exclude, bool withThreshold = true) const;
bool HasExpiredLeases () const;
bool IsExpired () const;
bool IsEmpty () const { return m_Leases.empty (); };
uint64_t GetExpirationTime () const { return m_ExpirationTime; };
bool ExpiresSoon(const uint64_t dlt=1000 * 5, const uint64_t fudge = 0) const ;
bool operator== (const LeaseSet& other) const
{ return m_BufferLen == other.m_BufferLen && !memcmp (m_Buffer, other.m_Buffer, m_BufferLen); };
// implements RoutingDestination
std::shared_ptr<const IdentityEx> GetIdentity () const { return m_Identity; };
void Encrypt (const uint8_t * data, uint8_t * encrypted, BN_CTX * ctx) const;
bool IsDestination () const { return true; };
private:
void ReadFromBuffer (bool readIdentity = true, bool verifySignature = true);
uint64_t ExtractTimestamp (const uint8_t * buf, size_t len) const; // returns max expiration time
private:
bool m_IsValid, m_StoreLeases; // we don't need to store leases for floodfill
std::set<std::shared_ptr<Lease>, LeaseCmp> m_Leases;
uint64_t m_ExpirationTime; // in milliseconds
std::shared_ptr<const IdentityEx> m_Identity;
uint8_t m_EncryptionKey[256];
uint8_t * m_Buffer;
size_t m_BufferLen;
};
/**
validate lease set buffer signature and extract expiration timestamp
@returns true if the leaseset is well formed and signature is valid
*/
bool LeaseSetBufferValidate(const uint8_t * ptr, size_t sz, uint64_t & expires);
class LocalLeaseSet
{
public:
LocalLeaseSet (std::shared_ptr<const IdentityEx> identity, const uint8_t * encryptionPublicKey, std::vector<std::shared_ptr<i2p::tunnel::InboundTunnel> > tunnels);
LocalLeaseSet (std::shared_ptr<const IdentityEx> identity, const uint8_t * buf, size_t len);
~LocalLeaseSet () { delete[] m_Buffer; };
const uint8_t * GetBuffer () const { return m_Buffer; };
uint8_t * GetSignature () { return m_Buffer + m_BufferLen - GetSignatureLen (); };
size_t GetBufferLen () const { return m_BufferLen; };
size_t GetSignatureLen () const { return m_Identity->GetSignatureLen (); };
uint8_t * GetLeases () { return m_Leases; };
const IdentHash& GetIdentHash () const { return m_Identity->GetIdentHash (); };
bool IsExpired () const;
uint64_t GetExpirationTime () const { return m_ExpirationTime; };
void SetExpirationTime (uint64_t expirationTime) { m_ExpirationTime = expirationTime; };
bool operator== (const LeaseSet& other) const
{ return m_BufferLen == other.GetBufferLen () && !memcmp (other.GetBuffer (), other.GetBuffer (), m_BufferLen); };
private:
uint64_t m_ExpirationTime; // in milliseconds
std::shared_ptr<const IdentityEx> m_Identity;
uint8_t * m_Buffer, * m_Leases;
size_t m_BufferLen;
};
}
}
#endif