AES/ElGamal tags per local destination

This commit is contained in:
orignal 2014-10-06 20:18:18 -04:00
parent 3787dc80d9
commit 93c1a0760d
12 changed files with 151 additions and 215 deletions

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@ -7,13 +7,14 @@
#include "TunnelPool.h"
#include "CryptoConst.h"
#include "NetDb.h"
#include "Garlic.h"
#include "Streaming.h"
namespace i2p
{
namespace stream
{
class StreamingDestination: public i2p::data::LocalDestination
class StreamingDestination: public i2p::garlic::GarlicDestination
{
public:

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@ -54,32 +54,131 @@ namespace garlic
m_Decryption.SetIV (iv);
m_Decryption.Decrypt (buf + 32, length - 32, buf + 32);
}
HandleAESBlock (buf + 32, length - 32, msg->from);
m_Tags.erase (it); // tag might be used only once
}
else
{
// tag not found. Use ElGamal
if (m_LocalDestination)
{
ElGamalBlock elGamal;
if (i2p::crypto::ElGamalDecrypt (m_LocalDestination->GetEncryptionPrivateKey (), buf, (uint8_t *)&elGamal, true))
{
m_Decryption.SetKey (elGamal.sessionKey);
uint8_t iv[32]; // IV is first 16 bytes
CryptoPP::SHA256().CalculateDigest(iv, elGamal.preIV, 32);
m_Decryption.SetIV (iv);
m_Decryption.Decrypt(buf + 514, length - 514, buf + 514);
}
else
LogPrint ("Failed to decrypt garlic");
}
ElGamalBlock elGamal;
if (i2p::crypto::ElGamalDecrypt (GetEncryptionPrivateKey (), buf, (uint8_t *)&elGamal, true))
{
m_Decryption.SetKey (elGamal.sessionKey);
uint8_t iv[32]; // IV is first 16 bytes
CryptoPP::SHA256().CalculateDigest(iv, elGamal.preIV, 32);
m_Decryption.SetIV (iv);
m_Decryption.Decrypt(buf + 514, length - 514, buf + 514);
HandleAESBlock (buf + 514, length - 514, msg->from);
}
else
LogPrint ("Can't use ElGamal without local destination");
LogPrint ("Failed to decrypt garlic");
}
DeleteI2NPMessage (msg);
}
void GarlicDestination::HandleAESBlock (uint8_t * buf, size_t len, i2p::tunnel::InboundTunnel * from)
{
uint16_t tagCount = be16toh (*(uint16_t *)buf);
buf += 2;
if (tagCount > 0)
{
for (int i = 0; i < tagCount; i++)
m_Tags[SessionTag(buf + i*32)] = nullptr;
}
buf += tagCount*32;
uint32_t payloadSize = be32toh (*(uint32_t *)buf);
if (payloadSize > len)
{
LogPrint ("Unexpected payload size ", payloadSize);
return;
}
buf += 4;
uint8_t * payloadHash = buf;
buf += 32;// payload hash.
if (*buf) // session key?
buf += 32; // new session key
buf++; // flag
// payload
uint8_t hash[32];
CryptoPP::SHA256().CalculateDigest(hash, buf, payloadSize);
if (memcmp (hash, payloadHash, 32)) // payload hash doesn't match
{
LogPrint ("Wrong payload hash");
return;
}
HandleGarlicPayload (buf, payloadSize, from);
}
void GarlicDestination::HandleGarlicPayload (uint8_t * buf, size_t len, i2p::tunnel::InboundTunnel * from)
{
int numCloves = buf[0];
LogPrint (numCloves," cloves");
buf++;
for (int i = 0; i < numCloves; i++)
{
// delivery instructions
uint8_t flag = buf[0];
buf++; // flag
if (flag & 0x80) // encrypted?
{
// TODO: implement
LogPrint ("Clove encrypted");
buf += 32;
}
GarlicDeliveryType deliveryType = (GarlicDeliveryType)((flag >> 5) & 0x03);
switch (deliveryType)
{
case eGarlicDeliveryTypeLocal:
LogPrint ("Garlic type local");
i2p::HandleI2NPMessage (CreateI2NPMessage (buf, GetI2NPMessageLength (buf), from));
break;
case eGarlicDeliveryTypeDestination:
{
LogPrint ("Garlic type destination");
buf += 32; // destination. check it later or for multiple destinations
I2NPHeader * header = (I2NPHeader *)buf;
if (header->typeID == eI2NPData)
HandleDataMessage (buf + sizeof (I2NPHeader), be16toh (header->size));
else
LogPrint ("Unexpected I2NP garlic message ", (int)header->typeID);
break;
}
case eGarlicDeliveryTypeTunnel:
{
LogPrint ("Garlic type tunnel");
// gwHash and gwTunnel sequence is reverted
uint8_t * gwHash = buf;
buf += 32;
uint32_t gwTunnel = be32toh (*(uint32_t *)buf);
buf += 4;
i2p::tunnel::OutboundTunnel * tunnel = nullptr;
if (from && from->GetTunnelPool ())
tunnel = from->GetTunnelPool ()->GetNextOutboundTunnel ();
if (tunnel) // we have send it through an outbound tunnel
{
I2NPMessage * msg = CreateI2NPMessage (buf, GetI2NPMessageLength (buf), from);
tunnel->SendTunnelDataMsg (gwHash, gwTunnel, msg);
}
else
LogPrint ("No outbound tunnels available for garlic clove");
break;
}
case eGarlicDeliveryTypeRouter:
LogPrint ("Garlic type router not supported");
buf += 32;
break;
default:
LogPrint ("Unknow garlic delivery type ", (int)deliveryType);
}
buf += GetI2NPMessageLength (buf); // I2NP
buf += 4; // CloveID
buf += 8; // Date
buf += 3; // Certificate
}
}
GarlicRoutingSession::GarlicRoutingSession (const i2p::data::RoutingDestination * destination, int numTags):
m_Destination (destination), m_IsAcknowledged (false), m_NumTags (numTags),
m_NextTag (-1), m_SessionTags (0), m_TagsCreationTime (0), m_LocalLeaseSet (nullptr)
@ -347,17 +446,6 @@ namespace garlic
for (auto it: m_Sessions)
delete it.second;
m_Sessions.clear ();
// TODO: delete remaining session decryptions
m_SessionTags.clear ();
}
void GarlicRouting::AddSessionKey (const uint8_t * key, const uint8_t * tag)
{
SessionDecryption * decryption = new SessionDecryption;
decryption->SetKey (key);
decryption->SetTagCount (1);
std::unique_lock<std::mutex> l(m_SessionsTagsMutex);
m_SessionTags[SessionTag(tag)] = decryption;
}
GarlicRoutingSession * GarlicRouting::GetRoutingSession (
@ -396,155 +484,13 @@ namespace garlic
void GarlicRouting::HandleGarlicMessage (I2NPMessage * msg)
{
uint8_t * buf = msg->GetPayload ();
uint32_t length = be32toh (*(uint32_t *)buf);
buf += 4;
auto it = m_SessionTags.find (SessionTag(buf));
if (it != m_SessionTags.end ())
{
// existing session
uint8_t iv[32]; // IV is first 16 bytes
CryptoPP::SHA256().CalculateDigest(iv, buf, 32);
it->second->SetIV (iv);
it->second->Decrypt (buf + 32, length - 32, buf + 32);
it->second->UseTag ();
HandleAESBlock (buf + 32, length - 32, it->second, msg->from);
if (!it->second->GetTagCount ()) delete it->second; // all tags were used
std::unique_lock<std::mutex> l(m_SessionsTagsMutex);
m_SessionTags.erase (it); // tag might be used only once
}
auto pool = msg->from ? msg->from->GetTunnelPool () : nullptr;
if (pool)
pool->GetGarlicDestination ().HandleGarlicMessage (msg);
else
{
// new session
i2p::tunnel::TunnelPool * pool = nullptr;
if (msg->from)
pool = msg->from->GetTunnelPool ();
ElGamalBlock elGamal;
if (i2p::crypto::ElGamalDecrypt (
pool ? pool->GetEncryptionPrivateKey () : i2p::context.GetPrivateKey (),
buf, (uint8_t *)&elGamal, true))
{
SessionDecryption * decryption = new SessionDecryption;
decryption->SetKey (elGamal.sessionKey);
uint8_t iv[32]; // IV is first 16 bytes
CryptoPP::SHA256().CalculateDigest(iv, elGamal.preIV, 32);
decryption->SetIV (iv);
decryption->Decrypt(buf + 514, length - 514, buf + 514);
HandleAESBlock (buf + 514, length - 514, decryption, msg->from);
}
else
LogPrint ("Failed to decrypt garlic");
}
DeleteI2NPMessage (msg);
}
void GarlicRouting::HandleAESBlock (uint8_t * buf, size_t len, SessionDecryption * decryption, i2p::tunnel::InboundTunnel * from)
{
uint16_t tagCount = be16toh (*(uint16_t *)buf);
buf += 2;
if (tagCount > 0)
{
decryption->AddTagCount (tagCount);
std::unique_lock<std::mutex> l(m_SessionsTagsMutex);
for (int i = 0; i < tagCount; i++)
m_SessionTags[SessionTag(buf + i*32)] = decryption;
}
buf += tagCount*32;
uint32_t payloadSize = be32toh (*(uint32_t *)buf);
if (payloadSize > len)
{
LogPrint ("Unexpected payload size ", payloadSize);
return;
}
buf += 4;
uint8_t * payloadHash = buf;
buf += 32;// payload hash.
if (*buf) // session key?
buf += 32; // new session key
buf++; // flag
// payload
uint8_t hash[32];
CryptoPP::SHA256().CalculateDigest(hash, buf, payloadSize);
if (memcmp (hash, payloadHash, 32)) // payload hash doesn't match
{
LogPrint ("Wrong payload hash");
return;
}
HandleGarlicPayload (buf, payloadSize, from);
}
void GarlicRouting::HandleGarlicPayload (uint8_t * buf, size_t len, i2p::tunnel::InboundTunnel * from)
{
int numCloves = buf[0];
LogPrint (numCloves," cloves");
buf++;
for (int i = 0; i < numCloves; i++)
{
// delivery instructions
uint8_t flag = buf[0];
buf++; // flag
if (flag & 0x80) // encrypted?
{
// TODO: implement
LogPrint ("Clove encrypted");
buf += 32;
}
GarlicDeliveryType deliveryType = (GarlicDeliveryType)((flag >> 5) & 0x03);
switch (deliveryType)
{
case eGarlicDeliveryTypeLocal:
LogPrint ("Garlic type local");
i2p::HandleI2NPMessage (CreateI2NPMessage (buf, GetI2NPMessageLength (buf), from));
break;
case eGarlicDeliveryTypeDestination:
{
LogPrint ("Garlic type destination");
buf += 32; // destination. check it later or for multiple destinations
I2NPHeader * header = (I2NPHeader *)buf;
if (header->typeID == eI2NPData)
{
auto pool = from ? from->GetTunnelPool () : nullptr;
if (pool)
pool->GetLocalDestination ().HandleDataMessage (buf + sizeof (I2NPHeader), be16toh (header->size));
else
LogPrint ("Local destination doesn't exist");
}
else
LogPrint ("Unexpected I2NP garlic message ", (int)header->typeID);
break;
}
case eGarlicDeliveryTypeTunnel:
{
LogPrint ("Garlic type tunnel");
// gwHash and gwTunnel sequence is reverted
uint8_t * gwHash = buf;
buf += 32;
uint32_t gwTunnel = be32toh (*(uint32_t *)buf);
buf += 4;
i2p::tunnel::OutboundTunnel * tunnel = nullptr;
if (from && from->GetTunnelPool ())
tunnel = from->GetTunnelPool ()->GetNextOutboundTunnel ();
if (tunnel) // we have send it through an outbound tunnel
{
I2NPMessage * msg = CreateI2NPMessage (buf, GetI2NPMessageLength (buf), from);
tunnel->SendTunnelDataMsg (gwHash, gwTunnel, msg);
}
else
LogPrint ("No outbound tunnels available for garlic clove");
break;
}
case eGarlicDeliveryTypeRouter:
LogPrint ("Garlic type router not supported");
buf += 32;
break;
default:
LogPrint ("Unknow garlic delivery type ", (int)deliveryType);
}
buf += GetI2NPMessageLength (buf); // I2NP
buf += 4; // CloveID
buf += 8; // Date
buf += 3; // Certificate
LogPrint ("Local destination doesn't exist");
DeleteI2NPMessage (msg);
}
}

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@ -11,7 +11,6 @@
#include "aes.h"
#include "I2NPProtocol.h"
#include "LeaseSet.h"
#include "Tunnel.h"
#include "Queue.h"
#include "Identity.h"
@ -40,22 +39,25 @@ namespace garlic
const int TAGS_EXPIRATION_TIMEOUT = 900; // 15 minutes
typedef i2p::data::Tag<32> SessionTag;
class GarlicDestination
class GarlicDestination: public i2p::data::LocalDestination
{
public:
GarlicDestination (i2p::data::LocalDestination * localDestination = nullptr):
m_LocalDestination (localDestination) {};
GarlicDestination () {};
~GarlicDestination ();
void AddSessionKey (const uint8_t * key, const uint8_t * tag); // one tag
void HandleGarlicMessage (I2NPMessage * msg);
private:
void HandleAESBlock (uint8_t * buf, size_t len, i2p::tunnel::InboundTunnel * from);
void HandleGarlicPayload (uint8_t * buf, size_t len, i2p::tunnel::InboundTunnel * from);
private:
i2p::crypto::CBCDecryption m_Decryption;
std::map<SessionTag, const uint8_t *> m_Tags; // tag->key, if null use key from decryption
i2p::data::LocalDestination * m_LocalDestination;
};
class GarlicRoutingSession
@ -95,22 +97,7 @@ namespace garlic
};
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 ();
@ -119,7 +106,6 @@ namespace garlic
void Start ();
void Stop ();
void PostI2NPMsg (I2NPMessage * msg);
void AddSessionKey (const uint8_t * key, const uint8_t * tag); // one tag
GarlicRoutingSession * GetRoutingSession (const i2p::data::RoutingDestination& destination, int numTags);
I2NPMessage * WrapSingleMessage (const i2p::data::RoutingDestination& destination, I2NPMessage * msg);
@ -133,9 +119,7 @@ namespace garlic
void Run ();
void HandleGarlicMessage (I2NPMessage * msg);
void HandleDeliveryStatusMessage (I2NPMessage * msg);
void HandleAESBlock (uint8_t * buf, size_t len, SessionDecryption * decryption, i2p::tunnel::InboundTunnel * from);
void HandleGarlicPayload (uint8_t * buf, size_t len, i2p::tunnel::InboundTunnel * from);
private:
bool m_IsRunning;
@ -146,10 +130,6 @@ namespace garlic
std::map<i2p::data::IdentHash, GarlicRoutingSession *> m_Sessions;
std::mutex m_CreatedSessionsMutex;
std::map<uint32_t, GarlicRoutingSession *> m_CreatedSessions; // msgID -> session
// incoming session
// multiple tags refer to one decyption
std::mutex m_SessionsTagsMutex;
std::map<SessionTag, SessionDecryption *> m_SessionTags; // tag -> decryption
};
extern GarlicRouting routing;

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@ -103,7 +103,7 @@ namespace i2p
I2NPMessage * CreateDatabaseLookupMsg (const uint8_t * key, const uint8_t * from,
uint32_t replyTunnelID, bool exploratory, std::set<i2p::data::IdentHash> * excludedPeers,
bool encryption)
bool encryption, i2p::tunnel::TunnelPool * pool)
{
I2NPMessage * m = NewI2NPMessage ();
uint8_t * buf = m->GetPayload ();
@ -159,7 +159,10 @@ namespace i2p
rnd.GenerateBlock (buf, 32); // key
buf[32] = 1; // 1 tag
rnd.GenerateBlock (buf + 33, 32); // tag
i2p::garlic::routing.AddSessionKey (buf, buf + 33); // introduce new key-tag to garlic engine
if (pool)
pool->GetGarlicDestination ().AddSessionKey (buf, buf + 33); // introduce new key-tag to garlic engine
else
LogPrint ("Destination for encrypteed reply not specified");
buf += 65;
}
m->len += (buf - m->GetPayload ());

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@ -99,6 +99,7 @@ namespace i2p
namespace tunnel
{
class InboundTunnel;
class TunnelPool;
}
const size_t I2NP_MAX_MESSAGE_SIZE = 32768;
@ -168,7 +169,8 @@ namespace tunnel
I2NPMessage * CreateDeliveryStatusMsg (uint32_t msgID);
I2NPMessage * CreateDatabaseLookupMsg (const uint8_t * key, const uint8_t * from,
uint32_t replyTunnelID, bool exploratory = false,
std::set<i2p::data::IdentHash> * excludedPeers = nullptr, bool encryption = false);
std::set<i2p::data::IdentHash> * excludedPeers = nullptr, bool encryption = false,
i2p::tunnel::TunnelPool * pool = nullptr);
I2NPMessage * CreateDatabaseSearchReply (const i2p::data::IdentHash& ident, const i2p::data::RouterInfo * floodfill);
I2NPMessage * CreateDatabaseStoreMsg (const i2p::data::RouterInfo * router = nullptr);

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@ -23,7 +23,8 @@ namespace data
const i2p::tunnel::InboundTunnel * replyTunnel)
{
I2NPMessage * msg = i2p::CreateDatabaseLookupMsg (m_Destination,
replyTunnel->GetNextIdentHash (), replyTunnel->GetNextTunnelID (), m_IsExploratory, &m_ExcludedPeers, m_IsLeaseSet);
replyTunnel->GetNextIdentHash (), replyTunnel->GetNextTunnelID (), m_IsExploratory,
&m_ExcludedPeers, m_IsLeaseSet, m_Pool);
if (m_IsLeaseSet) // wrap lookup message into garlic
msg = i2p::garlic::routing.WrapSingleMessage (*router, msg);
m_ExcludedPeers.insert (router->GetIdentHash ());
@ -102,7 +103,7 @@ namespace data
{
try
{
I2NPMessage * msg = m_Queue.GetNextWithTimeout (30000); // 30 sec
I2NPMessage * msg = m_Queue.GetNextWithTimeout (15000); // 15 sec
if (msg)
{
while (msg)

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@ -6,6 +6,7 @@
#include <cryptopp/osrng.h>
#include "Identity.h"
#include "RouterInfo.h"
#include "Garlic.h"
namespace i2p
{
@ -13,7 +14,7 @@ namespace i2p
const char ROUTER_KEYS[] = "router.keys";
const int ROUTER_INFO_UPDATE_INTERVAL = 1800; // 30 minutes
class RouterContext: public i2p::data::LocalDestination
class RouterContext: public i2p::garlic::GarlicDestination
{
public:

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@ -14,6 +14,7 @@
#include "LeaseSet.h"
#include "I2NPProtocol.h"
#include "Garlic.h"
#include "Tunnel.h"
namespace i2p
{

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@ -288,7 +288,7 @@ namespace tunnel
return tunnel;
}
TunnelPool * Tunnels::CreateTunnelPool (i2p::data::LocalDestination& localDestination, int numHops)
TunnelPool * Tunnels::CreateTunnelPool (i2p::garlic::GarlicDestination& localDestination, int numHops)
{
auto pool = new TunnelPool (localDestination, numHops);
std::unique_lock<std::mutex> l(m_PoolsMutex);

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@ -129,7 +129,7 @@ namespace tunnel
void PostTunnelData (I2NPMessage * msg);
template<class TTunnel>
TTunnel * CreateTunnel (TunnelConfig * config, OutboundTunnel * outboundTunnel = 0);
TunnelPool * CreateTunnelPool (i2p::data::LocalDestination& localDestination, int numHops);
TunnelPool * CreateTunnelPool (i2p::garlic::GarlicDestination& localDestination, int numHops);
void DeleteTunnelPool (TunnelPool * pool);
private:

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@ -10,7 +10,7 @@ namespace i2p
{
namespace tunnel
{
TunnelPool::TunnelPool (i2p::data::LocalDestination& localDestination, int numHops, int numTunnels):
TunnelPool::TunnelPool (i2p::garlic::GarlicDestination& localDestination, int numHops, int numTunnels):
m_LocalDestination (localDestination), m_NumHops (numHops), m_NumTunnels (numTunnels)
{
}

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@ -12,6 +12,7 @@
#include "I2NPProtocol.h"
#include "TunnelBase.h"
#include "RouterContext.h"
#include "Garlic.h"
namespace i2p
{
@ -25,13 +26,13 @@ namespace tunnel
{
public:
TunnelPool (i2p::data::LocalDestination& localDestination, int numHops, int numTunnels = 5);
TunnelPool (i2p::garlic::GarlicDestination& localDestination, int numHops, int numTunnels = 5);
~TunnelPool ();
const uint8_t * GetEncryptionPrivateKey () const { return m_LocalDestination.GetEncryptionPrivateKey (); };
const uint8_t * GetEncryptionPublicKey () const { return m_LocalDestination.GetEncryptionPublicKey (); };
const i2p::data::LocalDestination& GetLocalDestination () const { return m_LocalDestination; };
i2p::data::LocalDestination& GetLocalDestination () { return m_LocalDestination; };
i2p::garlic::GarlicDestination& GetGarlicDestination () const { return m_LocalDestination; };
bool IsExploratory () const { return GetIdentHash () == i2p::context.GetRouterIdentHash (); };
void CreateTunnels ();
@ -60,7 +61,7 @@ namespace tunnel
private:
i2p::data::LocalDestination& m_LocalDestination;
i2p::garlic::GarlicDestination& m_LocalDestination;
int m_NumHops, m_NumTunnels;
mutable std::mutex m_InboundTunnelsMutex;
std::set<InboundTunnel *, TunnelCreationTimeCmp> m_InboundTunnels; // recent tunnel appears first