i2pd/LeaseSet.cpp
2015-07-30 16:25:43 +02:00

158 lines
5.3 KiB
C++

#include <string.h>
#include "util/I2PEndian.h"
#include <cryptopp/dsa.h>
#include <cryptopp/osrng.h>
#include "crypto/CryptoConst.h"
#include "util/Log.h"
#include "util/Timestamp.h"
#include "NetDb.h"
#include "tunnel/TunnelPool.h"
#include "LeaseSet.h"
namespace i2p
{
namespace data
{
LeaseSet::LeaseSet (const uint8_t * buf, size_t len):
m_IsValid (true)
{
m_Buffer = new uint8_t[len];
memcpy (m_Buffer, buf, len);
m_BufferLen = len;
ReadFromBuffer ();
}
LeaseSet::LeaseSet (const i2p::tunnel::TunnelPool& pool):
m_IsValid (true)
{
// header
const i2p::data::LocalDestination * localDestination = pool.GetLocalDestination ();
if (!localDestination)
{
m_Buffer = nullptr;
m_BufferLen = 0;
m_IsValid = false;
LogPrint (eLogError, "Destination for local LeaseSet doesn't exist");
return;
}
m_Buffer = new uint8_t[MAX_LS_BUFFER_SIZE];
m_BufferLen = localDestination->GetIdentity ().ToBuffer (m_Buffer, MAX_LS_BUFFER_SIZE);
memcpy (m_Buffer + m_BufferLen, localDestination->GetEncryptionPublicKey (), 256);
m_BufferLen += 256;
auto signingKeyLen = localDestination->GetIdentity ().GetSigningPublicKeyLen ();
memset (m_Buffer + m_BufferLen, 0, signingKeyLen);
m_BufferLen += signingKeyLen;
auto tunnels = pool.GetInboundTunnels (5); // 5 tunnels maximum
m_Buffer[m_BufferLen] = tunnels.size (); // num leases
m_BufferLen++;
// leases
CryptoPP::AutoSeededRandomPool rnd;
for (auto it: tunnels)
{
memcpy (m_Buffer + m_BufferLen, it->GetNextIdentHash (), 32);
m_BufferLen += 32; // gateway id
htobe32buf (m_Buffer + m_BufferLen, it->GetNextTunnelID ());
m_BufferLen += 4; // tunnel id
uint64_t ts = it->GetCreationTime () + i2p::tunnel::TUNNEL_EXPIRATION_TIMEOUT - i2p::tunnel::TUNNEL_EXPIRATION_THRESHOLD; // 1 minute before expiration
ts *= 1000; // in milliseconds
ts += rnd.GenerateWord32 (0, 5); // + random milliseconds
htobe64buf (m_Buffer + m_BufferLen, ts);
m_BufferLen += 8; // end date
}
// signature
localDestination->Sign (m_Buffer, m_BufferLen, m_Buffer + m_BufferLen);
m_BufferLen += localDestination->GetIdentity ().GetSignatureLen ();
LogPrint ("Local LeaseSet of ", tunnels.size (), " leases created");
ReadFromBuffer ();
}
void LeaseSet::Update (const uint8_t * buf, size_t len)
{
m_Leases.clear ();
if (len > m_BufferLen)
{
auto oldBuffer = m_Buffer;
m_Buffer = new uint8_t[len];
delete[] oldBuffer;
}
memcpy (m_Buffer, buf, len);
m_BufferLen = len;
ReadFromBuffer ();
}
void LeaseSet::ReadFromBuffer ()
{
size_t size = m_Identity.FromBuffer (m_Buffer, m_BufferLen);
memcpy (m_EncryptionKey, m_Buffer + size, 256);
size += 256; // encryption key
size += m_Identity.GetSigningPublicKeyLen (); // unused signing key
uint8_t num = m_Buffer[size];
size++; // num
LogPrint ("LeaseSet num=", (int)num);
if (!num) m_IsValid = false;
// process leases
const uint8_t * leases = m_Buffer + size;
for (int i = 0; i < num; i++)
{
Lease lease;
lease.tunnelGateway = leases;
leases += 32; // gateway
lease.tunnelID = bufbe32toh (leases);
leases += 4; // tunnel ID
lease.endDate = bufbe64toh (leases);
leases += 8; // end date
m_Leases.push_back (lease);
// check if lease's gateway is in our netDb
if (!netdb.FindRouter (lease.tunnelGateway))
{
// if not found request it
LogPrint (eLogInfo, "Lease's tunnel gateway not found. Requested");
netdb.RequestDestination (lease.tunnelGateway);
}
}
// verify
if (!m_Identity.Verify (m_Buffer, leases - m_Buffer, leases))
{
LogPrint (eLogWarning, "LeaseSet verification failed");
m_IsValid = false;
}
}
const std::vector<Lease> LeaseSet::GetNonExpiredLeases (bool withThreshold) const
{
auto ts = i2p::util::GetMillisecondsSinceEpoch ();
std::vector<Lease> leases;
for (auto& it: m_Leases)
{
auto endDate = it.endDate;
if (!withThreshold)
endDate -= i2p::tunnel::TUNNEL_EXPIRATION_THRESHOLD*1000;
if (ts < endDate)
leases.push_back (it);
}
return leases;
}
bool LeaseSet::HasExpiredLeases () const
{
auto ts = i2p::util::GetMillisecondsSinceEpoch ();
for (auto& it: m_Leases)
if (ts >= it.endDate) return true;
return false;
}
bool LeaseSet::HasNonExpiredLeases () const
{
auto ts = i2p::util::GetMillisecondsSinceEpoch ();
for (auto& it: m_Leases)
if (ts < it.endDate) return true;
return false;
}
}
}