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Garlic.cpp
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/*
* Copyright (c) 2013-2022, The PurpleI2P Project
*
* This file is part of Purple i2pd project and licensed under BSD3
*
* See full license text in LICENSE file at top of project tree
*/
#include <inttypes.h>
#include "I2PEndian.h"
#include <map>
#include <string>
#include "Crypto.h"
#include "RouterContext.h"
#include "I2NPProtocol.h"
#include "Tunnel.h"
#include "TunnelPool.h"
#include "Transports.h"
#include "Timestamp.h"
#include "Log.h"
#include "FS.h"
#include "ECIESX25519AEADRatchetSession.h"
#include "Garlic.h"
namespace i2p
{
namespace garlic
{
GarlicRoutingSession::GarlicRoutingSession (GarlicDestination * owner, bool attachLeaseSet):
m_Owner (owner), m_LeaseSetUpdateStatus (attachLeaseSet ? eLeaseSetUpdated : eLeaseSetDoNotSend),
m_LeaseSetUpdateMsgID (0)
{
}
GarlicRoutingSession::GarlicRoutingSession ():
m_Owner (nullptr), m_LeaseSetUpdateStatus (eLeaseSetDoNotSend), m_LeaseSetUpdateMsgID (0)
{
}
GarlicRoutingSession::~GarlicRoutingSession ()
{
}
std::shared_ptr<GarlicRoutingPath> GarlicRoutingSession::GetSharedRoutingPath ()
{
if (!m_SharedRoutingPath) return nullptr;
uint32_t ts = i2p::util::GetSecondsSinceEpoch ();
if (m_SharedRoutingPath->numTimesUsed >= ROUTING_PATH_MAX_NUM_TIMES_USED ||
!m_SharedRoutingPath->outboundTunnel->IsEstablished () ||
ts*1000LL > m_SharedRoutingPath->remoteLease->endDate ||
ts > m_SharedRoutingPath->updateTime + ROUTING_PATH_EXPIRATION_TIMEOUT)
m_SharedRoutingPath = nullptr;
if (m_SharedRoutingPath) m_SharedRoutingPath->numTimesUsed++;
return m_SharedRoutingPath;
}
void GarlicRoutingSession::SetSharedRoutingPath (std::shared_ptr<GarlicRoutingPath> path)
{
if (path && path->outboundTunnel && path->remoteLease)
{
path->updateTime = i2p::util::GetSecondsSinceEpoch ();
path->numTimesUsed = 0;
}
else
path = nullptr;
m_SharedRoutingPath = path;
}
bool GarlicRoutingSession::MessageConfirmed (uint32_t msgID)
{
if (msgID == GetLeaseSetUpdateMsgID ())
{
SetLeaseSetUpdateStatus (eLeaseSetUpToDate);
SetLeaseSetUpdateMsgID (0);
LogPrint (eLogInfo, "Garlic: LeaseSet update confirmed");
return true;
}
return false;
}
void GarlicRoutingSession::CleanupUnconfirmedLeaseSet (uint64_t ts)
{
if (m_LeaseSetUpdateMsgID && ts*1000LL > m_LeaseSetSubmissionTime + LEASET_CONFIRMATION_TIMEOUT)
{
if (GetOwner ())
GetOwner ()->RemoveDeliveryStatusSession (m_LeaseSetUpdateMsgID);
m_LeaseSetUpdateMsgID = 0;
}
}
std::shared_ptr<I2NPMessage> GarlicRoutingSession::CreateEncryptedDeliveryStatusMsg (uint32_t msgID)
{
auto msg = CreateDeliveryStatusMsg (msgID);
if (GetOwner ())
{
//encrypt
uint8_t key[32], tag[32];
RAND_bytes (key, 32); // random session key
RAND_bytes (tag, 32); // random session tag
GetOwner ()->SubmitSessionKey (key, tag);
ElGamalAESSession garlic (key, tag);
msg = garlic.WrapSingleMessage (msg);
}
return msg;
}
ElGamalAESSession::ElGamalAESSession (GarlicDestination * owner,
std::shared_ptr<const i2p::data::RoutingDestination> destination, int numTags, bool attachLeaseSet):
GarlicRoutingSession (owner, attachLeaseSet),
m_Destination (destination), m_NumTags (numTags)
{
// create new session tags and session key
RAND_bytes (m_SessionKey, 32);
m_Encryption.SetKey (m_SessionKey);
}
ElGamalAESSession::ElGamalAESSession (const uint8_t * sessionKey, const SessionTag& sessionTag):
m_NumTags(1)
{
memcpy (m_SessionKey, sessionKey, 32);
m_Encryption.SetKey (m_SessionKey);
m_SessionTags.push_back (sessionTag);
m_SessionTags.back ().creationTime = i2p::util::GetSecondsSinceEpoch ();
}
std::shared_ptr<I2NPMessage> ElGamalAESSession::WrapSingleMessage (std::shared_ptr<const I2NPMessage> msg)
{
auto m = NewI2NPMessage ();
m->Align (12); // in order to get buf aligned to 16 (12 + 4)
size_t len = 0;
uint8_t * buf = m->GetPayload () + 4; // 4 bytes for length
// find non-expired tag
bool tagFound = false;
SessionTag tag;
if (m_NumTags > 0)
{
uint32_t ts = i2p::util::GetSecondsSinceEpoch ();
while (!m_SessionTags.empty ())
{
if (ts < m_SessionTags.front ().creationTime + OUTGOING_TAGS_EXPIRATION_TIMEOUT)
{
tag = m_SessionTags.front ();
m_SessionTags.pop_front (); // use same tag only once
tagFound = true;
break;
}
else
m_SessionTags.pop_front (); // remove expired tag
}
}
// create message
if (!tagFound) // new session
{
LogPrint (eLogInfo, "Garlic: No tags available, will use ElGamal");
if (!m_Destination)
{
LogPrint (eLogError, "Garlic: Can't use ElGamal for unknown destination");
return nullptr;
}
// create ElGamal block
ElGamalBlock elGamal;
memcpy (elGamal.sessionKey, m_SessionKey, 32);
RAND_bytes (elGamal.preIV, 32); // Pre-IV
uint8_t iv[32]; // IV is first 16 bytes
SHA256(elGamal.preIV, 32, iv);
m_Destination->Encrypt ((uint8_t *)&elGamal, buf);
m_Encryption.SetIV (iv);
buf += 514;
len += 514;
}
else // existing session
{
// session tag
memcpy (buf, tag, 32);
uint8_t iv[32]; // IV is first 16 bytes
SHA256(tag, 32, iv);
m_Encryption.SetIV (iv);
buf += 32;
len += 32;
}
// AES block
len += CreateAESBlock (buf, msg);
htobe32buf (m->GetPayload (), len);
m->len += len + 4;
m->FillI2NPMessageHeader (eI2NPGarlic);
return m;
}
size_t ElGamalAESSession::CreateAESBlock (uint8_t * buf, std::shared_ptr<const I2NPMessage> msg)
{
size_t blockSize = 0;
bool createNewTags = GetOwner () && m_NumTags && ((int)m_SessionTags.size () <= m_NumTags*2/3);
UnconfirmedTags * newTags = createNewTags ? GenerateSessionTags () : nullptr;
htobuf16 (buf, newTags ? htobe16 (newTags->numTags) : 0); // tag count
blockSize += 2;
if (newTags) // session tags recreated
{
for (int i = 0; i < newTags->numTags; i++)
{
memcpy (buf + blockSize, newTags->sessionTags[i], 32); // tags
blockSize += 32;
}
}
uint32_t * payloadSize = (uint32_t *)(buf + blockSize);
blockSize += 4;
uint8_t * payloadHash = buf + blockSize;
blockSize += 32;
buf[blockSize] = 0; // flag
blockSize++;
size_t len = CreateGarlicPayload (buf + blockSize, msg, newTags);
htobe32buf (payloadSize, len);
SHA256(buf + blockSize, len, payloadHash);
blockSize += len;
size_t rem = blockSize % 16;
if (rem)
blockSize += (16-rem); //padding
m_Encryption.Encrypt(buf, blockSize, buf);
return blockSize;
}
size_t ElGamalAESSession::CreateGarlicPayload (uint8_t * payload, std::shared_ptr<const I2NPMessage> msg, UnconfirmedTags * newTags)
{
uint64_t ts = i2p::util::GetMillisecondsSinceEpoch ();
uint32_t msgID;
RAND_bytes ((uint8_t *)&msgID, 4);
size_t size = 0;
uint8_t * numCloves = payload + size;
*numCloves = 0;
size++;
if (GetOwner ())
{
// resubmit non-confirmed LeaseSet
if (GetLeaseSetUpdateStatus () == eLeaseSetSubmitted && ts > GetLeaseSetSubmissionTime () + LEASET_CONFIRMATION_TIMEOUT)
{
SetLeaseSetUpdateStatus (eLeaseSetUpdated);
SetSharedRoutingPath (nullptr); // invalidate path since leaseset was not confirmed
}
// attach DeviveryStatus if necessary
if (newTags || GetLeaseSetUpdateStatus () == eLeaseSetUpdated) // new tags created or leaseset updated
{
// clove is DeliveryStatus
auto cloveSize = CreateDeliveryStatusClove (payload + size, msgID);
if (cloveSize > 0) // successive?
{
size += cloveSize;
(*numCloves)++;
if (newTags) // new tags created
{
newTags->msgID = msgID;
m_UnconfirmedTagsMsgs.insert (std::make_pair(msgID, std::unique_ptr<UnconfirmedTags>(newTags)));
newTags = nullptr; // got acquired
}
GetOwner ()->DeliveryStatusSent (shared_from_this (), msgID);
}
else
LogPrint (eLogWarning, "Garlic: DeliveryStatus clove was not created");
}
// attach LeaseSet
if (GetLeaseSetUpdateStatus () == eLeaseSetUpdated)
{
if (GetLeaseSetUpdateMsgID ()) GetOwner ()->RemoveDeliveryStatusSession (GetLeaseSetUpdateMsgID ()); // remove previous
SetLeaseSetUpdateStatus (eLeaseSetSubmitted);
SetLeaseSetUpdateMsgID (msgID);
SetLeaseSetSubmissionTime (ts);
// clove if our leaseSet must be attached
auto leaseSet = CreateDatabaseStoreMsg (GetOwner ()->GetLeaseSet ());
size += CreateGarlicClove (payload + size, leaseSet, false);
(*numCloves)++;
}
}
if (msg) // clove message itself if presented
{
size += CreateGarlicClove (payload + size, msg, m_Destination ? m_Destination->IsDestination () : false);
(*numCloves)++;
}
memset (payload + size, 0, 3); // certificate of message
size += 3;
htobe32buf (payload + size, msgID); // MessageID
size += 4;
htobe64buf (payload + size, ts + 8000); // Expiration of message, 8 sec
size += 8;
if (newTags) delete newTags; // not acquired, delete
return size;
}
size_t ElGamalAESSession::CreateGarlicClove (uint8_t * buf, std::shared_ptr<const I2NPMessage> msg, bool isDestination)
{
uint64_t ts = i2p::util::GetMillisecondsSinceEpoch () + 8000; // 8 sec
size_t size = 0;
if (isDestination)
{
buf[size] = eGarlicDeliveryTypeDestination << 5;// delivery instructions flag destination
size++;
memcpy (buf + size, m_Destination->GetIdentHash (), 32);
size += 32;
}
else
{
buf[size] = 0;// delivery instructions flag local
size++;
}
memcpy (buf + size, msg->GetBuffer (), msg->GetLength ());
size += msg->GetLength ();
uint32_t cloveID;
RAND_bytes ((uint8_t *)&cloveID, 4);
htobe32buf (buf + size, cloveID); // CloveID
size += 4;
htobe64buf (buf + size, ts); // Expiration of clove
size += 8;
memset (buf + size, 0, 3); // certificate of clove
size += 3;
return size;
}
size_t ElGamalAESSession::CreateDeliveryStatusClove (uint8_t * buf, uint32_t msgID)
{
size_t size = 0;
if (GetOwner ())
{
auto inboundTunnel = GetOwner ()->GetTunnelPool ()->GetNextInboundTunnel ();
if (inboundTunnel)
{
buf[size] = eGarlicDeliveryTypeTunnel << 5; // delivery instructions flag tunnel
size++;
// hash and tunnelID sequence is reversed for Garlic
memcpy (buf + size, inboundTunnel->GetNextIdentHash (), 32); // To Hash
size += 32;
htobe32buf (buf + size, inboundTunnel->GetNextTunnelID ()); // tunnelID
size += 4;
// create msg
auto msg = CreateEncryptedDeliveryStatusMsg (msgID);
if (msg)
{
memcpy (buf + size, msg->GetBuffer (), msg->GetLength ());
size += msg->GetLength ();
}
// fill clove
uint64_t ts = i2p::util::GetMillisecondsSinceEpoch () + 8000; // 8 sec
uint32_t cloveID;
RAND_bytes ((uint8_t *)&cloveID, 4);
htobe32buf (buf + size, cloveID); // CloveID
size += 4;
htobe64buf (buf + size, ts); // Expiration of clove
size += 8;
memset (buf + size, 0, 3); // certificate of clove
size += 3;
}
else
LogPrint (eLogError, "Garlic: No inbound tunnels in the pool for DeliveryStatus");
}
else
LogPrint (eLogWarning, "Garlic: Missing local LeaseSet");
return size;
}
ElGamalAESSession::UnconfirmedTags * ElGamalAESSession::GenerateSessionTags ()
{
auto tags = new UnconfirmedTags (m_NumTags);
tags->tagsCreationTime = i2p::util::GetSecondsSinceEpoch ();
for (int i = 0; i < m_NumTags; i++)
{
RAND_bytes (tags->sessionTags[i], 32);
tags->sessionTags[i].creationTime = tags->tagsCreationTime;
}
return tags;
}
bool ElGamalAESSession::MessageConfirmed (uint32_t msgID)
{
TagsConfirmed (msgID);
if (!GarlicRoutingSession::MessageConfirmed (msgID))
CleanupExpiredTags ();
return true;
}
void ElGamalAESSession::TagsConfirmed (uint32_t msgID)
{
uint32_t ts = i2p::util::GetSecondsSinceEpoch ();
auto it = m_UnconfirmedTagsMsgs.find (msgID);
if (it != m_UnconfirmedTagsMsgs.end ())
{
auto& tags = it->second;
if (ts < tags->tagsCreationTime + OUTGOING_TAGS_EXPIRATION_TIMEOUT)
{
for (int i = 0; i < tags->numTags; i++)
m_SessionTags.push_back (tags->sessionTags[i]);
}
m_UnconfirmedTagsMsgs.erase (it);
}
}
bool ElGamalAESSession::CleanupExpiredTags ()
{
auto ts = i2p::util::GetSecondsSinceEpoch ();
for (auto it = m_SessionTags.begin (); it != m_SessionTags.end ();)
{
if (ts >= it->creationTime + OUTGOING_TAGS_EXPIRATION_TIMEOUT)
it = m_SessionTags.erase (it);
else
++it;
}
CleanupUnconfirmedTags ();
CleanupUnconfirmedLeaseSet (ts);
return !m_SessionTags.empty () || !m_UnconfirmedTagsMsgs.empty ();
}
bool ElGamalAESSession::CleanupUnconfirmedTags ()
{
bool ret = false;
uint32_t ts = i2p::util::GetSecondsSinceEpoch ();
// delete expired unconfirmed tags
for (auto it = m_UnconfirmedTagsMsgs.begin (); it != m_UnconfirmedTagsMsgs.end ();)
{
if (ts >= it->second->tagsCreationTime + OUTGOING_TAGS_CONFIRMATION_TIMEOUT)
{
if (GetOwner ())
GetOwner ()->RemoveDeliveryStatusSession (it->first);
it = m_UnconfirmedTagsMsgs.erase (it);
ret = true;
}
else
++it;
}
return ret;
}
GarlicDestination::GarlicDestination (): m_NumTags (32), // 32 tags by default
m_PayloadBuffer (nullptr), m_NumRatchetInboundTags (0) // 0 means standard
{
}
GarlicDestination::~GarlicDestination ()
{
if (m_PayloadBuffer)
delete[] m_PayloadBuffer;
}
void GarlicDestination::CleanUp ()
{
for (auto it: m_Sessions)
it.second->SetOwner (nullptr);
m_Sessions.clear ();
m_DeliveryStatusSessions.clear ();
m_Tags.clear ();
for (auto it: m_ECIESx25519Sessions)
{
it.second->Terminate ();
it.second->SetOwner (nullptr);
}
m_ECIESx25519Sessions.clear ();
m_ECIESx25519Tags.clear ();
}
void GarlicDestination::AddSessionKey (const uint8_t * key, const uint8_t * tag)
{
if (key)
{
uint32_t ts = i2p::util::GetSecondsSinceEpoch ();
m_Tags[SessionTag(tag, ts)] = std::make_shared<AESDecryption>(key);
}
}
void GarlicDestination::AddECIESx25519Key (const uint8_t * key, const uint8_t * tag)
{
uint64_t t;
memcpy (&t, tag, 8);
AddECIESx25519Key (key, t);
}
void GarlicDestination::AddECIESx25519Key (const uint8_t * key, uint64_t tag)
{
auto tagset = std::make_shared<SymmetricKeyTagSet>(this, key);
m_ECIESx25519Tags.emplace (tag, ECIESX25519AEADRatchetIndexTagset{0, tagset});
}
bool GarlicDestination::SubmitSessionKey (const uint8_t * key, const uint8_t * tag)
{
AddSessionKey (key, tag);
return true;
}
void GarlicDestination::SubmitECIESx25519Key (const uint8_t * key, uint64_t tag)
{
AddECIESx25519Key (key, tag);
}
void GarlicDestination::HandleGarlicMessage (std::shared_ptr<I2NPMessage> msg)
{
uint8_t * buf = msg->GetPayload ();
uint32_t length = bufbe32toh (buf);
if (length > msg->GetLength ())
{
LogPrint (eLogWarning, "Garlic: Message length ", length, " exceeds I2NP message length ", msg->GetLength ());
return;
}
auto mod = length & 0x0f; // %16
buf += 4; // length
bool found = false;
if (SupportsEncryptionType (i2p::data::CRYPTO_KEY_TYPE_ECIES_X25519_AEAD))
// try ECIESx25519 tag
found = HandleECIESx25519TagMessage (buf, length);
if (!found)
{
auto it = !mod ? m_Tags.find (SessionTag(buf)) : m_Tags.end (); // AES block is multiple of 16
// AES tag might be used even if encryption type is not ElGamal/AES
if (it != m_Tags.end ()) // try AES tag
{
// tag found. Use AES
auto decryption = it->second;
m_Tags.erase (it); // tag might be used only once
if (length >= 32)
{
uint8_t iv[32]; // IV is first 16 bytes
SHA256(buf, 32, iv);
decryption->SetIV (iv);
decryption->Decrypt (buf + 32, length - 32, buf + 32);
HandleAESBlock (buf + 32, length - 32, decryption, msg->from);
found = true;
}
else
LogPrint (eLogWarning, "Garlic: Message length ", length, " is less than 32 bytes");
}
if (!found) // assume new session
{
// AES tag not found. Handle depending on encryption type
// try ElGamal/AES first if leading block is 514
ElGamalBlock elGamal;
if (mod == 2 && length >= 514 && SupportsEncryptionType (i2p::data::CRYPTO_KEY_TYPE_ELGAMAL) &&
Decrypt (buf, (uint8_t *)&elGamal, i2p::data::CRYPTO_KEY_TYPE_ELGAMAL))
{
auto decryption = std::make_shared<AESDecryption>(elGamal.sessionKey);
uint8_t iv[32]; // IV is first 16 bytes
SHA256(elGamal.preIV, 32, iv);
decryption->SetIV (iv);
decryption->Decrypt(buf + 514, length - 514, buf + 514);
HandleAESBlock (buf + 514, length - 514, decryption, msg->from);
}
else if (SupportsEncryptionType (i2p::data::CRYPTO_KEY_TYPE_ECIES_X25519_AEAD))
{
// otherwise ECIESx25519
auto session = std::make_shared<ECIESX25519AEADRatchetSession> (this, false); // incoming
if (!session->HandleNextMessage (buf, length, nullptr, 0))
{
// try to generate more tags for last tagset
if (m_LastTagset && (m_LastTagset->GetNextIndex () - m_LastTagset->GetTrimBehind () < 3*ECIESX25519_MAX_NUM_GENERATED_TAGS))
{
uint64_t missingTag; memcpy (&missingTag, buf, 8);
auto maxTags = std::max (m_NumRatchetInboundTags, ECIESX25519_MAX_NUM_GENERATED_TAGS);
LogPrint (eLogWarning, "Garlic: Trying to generate more ECIES-X25519-AEAD-Ratchet tags");
for (int i = 0; i < maxTags; i++)
{
auto nextTag = AddECIESx25519SessionNextTag (m_LastTagset);
if (!nextTag)
{
LogPrint (eLogError, "Garlic: Can't create new ECIES-X25519-AEAD-Ratchet tag for last tagset");
break;
}
if (nextTag == missingTag)
{
LogPrint (eLogDebug, "Garlic: Missing ECIES-X25519-AEAD-Ratchet tag was generated");
if (m_LastTagset->HandleNextMessage (buf, length, m_ECIESx25519Tags[nextTag].index))
found = true;
break;
}
}
if (!found) m_LastTagset = nullptr;
}
if (!found)
LogPrint (eLogError, "Garlic: Can't handle ECIES-X25519-AEAD-Ratchet message");
}
}
else
LogPrint (eLogError, "Garlic: Failed to decrypt message");
}
}
}
bool GarlicDestination::HandleECIESx25519TagMessage (uint8_t * buf, size_t len)
{
uint64_t tag;
memcpy (&tag, buf, 8);
auto it = m_ECIESx25519Tags.find (tag);
if (it != m_ECIESx25519Tags.end ())
{
if (it->second.tagset->HandleNextMessage (buf, len, it->second.index))
m_LastTagset = it->second.tagset;
else
LogPrint (eLogError, "Garlic: Can't handle ECIES-X25519-AEAD-Ratchet message");
m_ECIESx25519Tags.erase (it);
return true;
}
return false;
}
void GarlicDestination::HandleAESBlock (uint8_t * buf, size_t len, std::shared_ptr<AESDecryption> decryption,
std::shared_ptr<i2p::tunnel::InboundTunnel> from)
{
uint16_t tagCount = bufbe16toh (buf);
buf += 2; len -= 2;
if (tagCount > 0)
{
if (tagCount*32 > len)
{
LogPrint (eLogError, "Garlic: Tag count ", tagCount, " exceeds length ", len);
return ;
}
uint32_t ts = i2p::util::GetSecondsSinceEpoch ();
for (int i = 0; i < tagCount; i++)
m_Tags[SessionTag(buf + i*32, ts)] = decryption;
}
buf += tagCount*32;
len -= tagCount*32;
uint32_t payloadSize = bufbe32toh (buf);
if (payloadSize > len)
{
LogPrint (eLogError, "Garlic: 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 digest[32];
SHA256 (buf, payloadSize, digest);
if (memcmp (payloadHash, digest, 32)) // payload hash doesn't match
{
LogPrint (eLogError, "Garlic: Wrong payload hash");
return;
}
HandleGarlicPayload (buf, payloadSize, from);
}
void GarlicDestination::HandleGarlicPayload (uint8_t * buf, size_t len, std::shared_ptr<i2p::tunnel::InboundTunnel> from)
{
if (len < 1)
{
LogPrint (eLogError, "Garlic: Payload is too short");
return;
}
int numCloves = buf[0];
LogPrint (eLogDebug, "Garlic: ", numCloves," cloves");
buf++; len--;
for (int i = 0; i < numCloves; i++)
{
const uint8_t * buf1 = buf;
// delivery instructions
uint8_t flag = buf[0];
buf++; // flag
if (flag & 0x80) // encrypted?
{
// TODO: implement
LogPrint (eLogWarning, "Garlic: Clove encrypted");
buf += 32;
}
ptrdiff_t offset = buf - buf1;
GarlicDeliveryType deliveryType = (GarlicDeliveryType)((flag >> 5) & 0x03);
switch (deliveryType)
{
case eGarlicDeliveryTypeLocal:
LogPrint (eLogDebug, "Garlic: Type local");
if (offset > (int)len)
{
LogPrint (eLogError, "Garlic: Message is too short");
break;
}
HandleI2NPMessage (buf, len - offset);
break;
case eGarlicDeliveryTypeDestination:
LogPrint (eLogDebug, "Garlic: Type destination");
buf += 32; // destination. check it later or for multiple destinations
offset = buf - buf1;
if (offset > (int)len)
{
LogPrint (eLogError, "Garlic: Message is too short");
break;
}
HandleI2NPMessage (buf, len - offset);
break;
case eGarlicDeliveryTypeTunnel:
{
LogPrint (eLogDebug, "Garlic: Type tunnel");
// gwHash and gwTunnel sequence is reverted
uint8_t * gwHash = buf;
buf += 32;
offset = buf - buf1;
if (offset + 4 > (int)len)
{
LogPrint (eLogError, "Garlic: Message is too short");
break;
}
uint32_t gwTunnel = bufbe32toh (buf);
buf += 4; offset += 4;
auto msg = CreateI2NPMessage (buf, GetI2NPMessageLength (buf, len - offset), from);
if (from) // received through an inbound tunnel
{
std::shared_ptr<i2p::tunnel::OutboundTunnel> tunnel;
if (from->GetTunnelPool ())
tunnel = from->GetTunnelPool ()->GetNextOutboundTunnel ();
else
LogPrint (eLogError, "Garlic: Tunnel pool is not set for inbound tunnel");
if (tunnel) // we have sent it through an outbound tunnel
tunnel->SendTunnelDataMsg (gwHash, gwTunnel, msg);
else
LogPrint (eLogWarning, "Garlic: No outbound tunnels available for garlic clove");
}
else // received directly
i2p::transport::transports.SendMessage (gwHash, i2p::CreateTunnelGatewayMsg (gwTunnel, msg)); // send directly
break;
}
case eGarlicDeliveryTypeRouter:
{
uint8_t * ident = buf;
buf += 32;
offset = buf - buf1;
if (!from) // received directly
{
if (offset > (int)len)
{
LogPrint (eLogError, "Garlic: Message is too short");
break;
}
i2p::transport::transports.SendMessage (ident,
CreateI2NPMessage (buf, GetI2NPMessageLength (buf, len - offset)));
}
else
LogPrint (eLogWarning, "Garlic: Type router for inbound tunnels not supported");
break;
}
default:
LogPrint (eLogWarning, "Garlic: Unknown delivery type ", (int)deliveryType);
}
if (offset > (int)len)
{
LogPrint (eLogError, "Garlic: Message is too short");
break;
}
buf += GetI2NPMessageLength (buf, len - offset); // I2NP
buf += 4; // CloveID
buf += 8; // Date
buf += 3; // Certificate
offset = buf - buf1;
if (offset > (int)len)
{
LogPrint (eLogError, "Garlic: Clove is too long");
break;
}
len -= offset;
}
}
std::shared_ptr<I2NPMessage> GarlicDestination::WrapMessageForRouter (std::shared_ptr<const i2p::data::RouterInfo> router,
std::shared_ptr<I2NPMessage> msg)
{
if (router->GetEncryptionType () == i2p::data::CRYPTO_KEY_TYPE_ECIES_X25519_AEAD)
return WrapECIESX25519MessageForRouter (msg, router->GetIdentity ()->GetEncryptionPublicKey ());
else
{
auto session = GetRoutingSession (router, false);
return session->WrapSingleMessage (msg);
}
}
std::shared_ptr<GarlicRoutingSession> GarlicDestination::GetRoutingSession (
std::shared_ptr<const i2p::data::RoutingDestination> destination, bool attachLeaseSet)
{
if (destination->GetEncryptionType () == i2p::data::CRYPTO_KEY_TYPE_ECIES_X25519_AEAD &&
SupportsEncryptionType (i2p::data::CRYPTO_KEY_TYPE_ECIES_X25519_AEAD))
{
ECIESX25519AEADRatchetSessionPtr session;
uint8_t staticKey[32];
destination->Encrypt (nullptr, staticKey); // we are supposed to get static key
auto it = m_ECIESx25519Sessions.find (staticKey);
if (it != m_ECIESx25519Sessions.end ())
{
session = it->second;
if (session->IsInactive (i2p::util::GetSecondsSinceEpoch ()))
{
LogPrint (eLogDebug, "Garlic: Session restarted");
session = nullptr;
}
}
if (!session)
{
session = std::make_shared<ECIESX25519AEADRatchetSession> (this, true);
session->SetRemoteStaticKey (staticKey);
}
if (destination->IsDestination ())
session->SetDestination (destination->GetIdentHash ()); // TODO: remove
return session;
}
else
{
ElGamalAESSessionPtr session;
{
std::unique_lock<std::mutex> l(m_SessionsMutex);
auto it = m_Sessions.find (destination->GetIdentHash ());
if (it != m_Sessions.end ())
session = it->second;
}
if (!session)
{
session = std::make_shared<ElGamalAESSession> (this, destination,
attachLeaseSet ? m_NumTags : 4, attachLeaseSet); // specified num tags for connections and 4 for LS requests
std::unique_lock<std::mutex> l(m_SessionsMutex);
m_Sessions[destination->GetIdentHash ()] = session;
}
return session;
}
return nullptr;
}
void GarlicDestination::CleanupExpiredTags ()
{
// incoming
uint32_t ts = i2p::util::GetSecondsSinceEpoch ();
int numExpiredTags = 0;
for (auto it = m_Tags.begin (); it != m_Tags.end ();)
{
if (ts > it->first.creationTime + INCOMING_TAGS_EXPIRATION_TIMEOUT)
{
numExpiredTags++;
it = m_Tags.erase (it);
}
else
++it;
}
if (numExpiredTags > 0)
LogPrint (eLogDebug, "Garlic: ", numExpiredTags, " tags expired for ", GetIdentHash().ToBase64 ());
// outgoing
{
std::unique_lock<std::mutex> l(m_SessionsMutex);
for (auto it = m_Sessions.begin (); it != m_Sessions.end ();)
{
it->second->GetSharedRoutingPath (); // delete shared path if necessary
if (!it->second->CleanupExpiredTags ())
{
LogPrint (eLogInfo, "Garlic: Routing session to ", it->first.ToBase32 (), " deleted");
it->second->SetOwner (nullptr);
it = m_Sessions.erase (it);
}
else
++it;
}
}
// delivery status sessions
{
std::unique_lock<std::mutex> l(m_DeliveryStatusSessionsMutex);
for (auto it = m_DeliveryStatusSessions.begin (); it != m_DeliveryStatusSessions.end (); )
{
if (it->second->GetOwner () != this)
it = m_DeliveryStatusSessions.erase (it);
else
++it;
}
}
// ECIESx25519
for (auto it = m_ECIESx25519Sessions.begin (); it != m_ECIESx25519Sessions.end ();)
{
if (it->second->CheckExpired (ts))
{
it->second->Terminate ();
it = m_ECIESx25519Sessions.erase (it);
}
else
++it;
}
numExpiredTags = 0;
for (auto it = m_ECIESx25519Tags.begin (); it != m_ECIESx25519Tags.end ();)
{
if (it->second.tagset->IsExpired (ts) || it->second.tagset->IsIndexExpired (it->second.index))
{
it->second.tagset->DeleteSymmKey (it->second.index);
it = m_ECIESx25519Tags.erase (it);
numExpiredTags++;
}
else
{
auto session = it->second.tagset->GetSession ();
if (!session || session->IsTerminated())
{
it = m_ECIESx25519Tags.erase (it);
numExpiredTags++;
}
else
++it;
}
}
if (numExpiredTags > 0)
LogPrint (eLogDebug, "Garlic: ", numExpiredTags, " ECIESx25519 tags expired for ", GetIdentHash().ToBase64 ());
if (m_LastTagset && m_LastTagset->IsExpired (ts))
m_LastTagset = nullptr;
}
void GarlicDestination::RemoveDeliveryStatusSession (uint32_t msgID)
{
std::unique_lock<std::mutex> l(m_DeliveryStatusSessionsMutex);
m_DeliveryStatusSessions.erase (msgID);
}
void GarlicDestination::DeliveryStatusSent (GarlicRoutingSessionPtr session, uint32_t msgID)
{
std::unique_lock<std::mutex> l(m_DeliveryStatusSessionsMutex);
m_DeliveryStatusSessions[msgID] = session;
}
void GarlicDestination::HandleDeliveryStatusMessage (uint32_t msgID)
{
GarlicRoutingSessionPtr session;
{
std::unique_lock<std::mutex> l(m_DeliveryStatusSessionsMutex);
auto it = m_DeliveryStatusSessions.find (msgID);
if (it != m_DeliveryStatusSessions.end ())
{
session = it->second;
m_DeliveryStatusSessions.erase (it);
}
}
if (session)
{
session->MessageConfirmed (msgID);
LogPrint (eLogDebug, "Garlic: Message ", msgID, " acknowledged");
}
}
void GarlicDestination::SetLeaseSetUpdated ()
{
{
std::unique_lock<std::mutex> l(m_SessionsMutex);
for (auto& it: m_Sessions)
it.second->SetLeaseSetUpdated ();
}
for (auto& it: m_ECIESx25519Sessions)
it.second->SetLeaseSetUpdated ();
}
void GarlicDestination::ProcessGarlicMessage (std::shared_ptr<I2NPMessage> msg)
{
HandleGarlicMessage (msg);
}
void GarlicDestination::ProcessDeliveryStatusMessage (std::shared_ptr<I2NPMessage> msg)
{
uint32_t msgID = bufbe32toh (msg->GetPayload () + DELIVERY_STATUS_MSGID_OFFSET);
HandleDeliveryStatusMessage (msgID);
}
void GarlicDestination::SaveTags ()
{
if (m_Tags.empty ()) return;
std::string ident = GetIdentHash().ToBase32();
std::string path = i2p::fs::DataDirPath("tags", (ident + ".tags"));
std::ofstream f (path, std::ofstream::binary | std::ofstream::out | std::ofstream::trunc);
uint32_t ts = i2p::util::GetSecondsSinceEpoch ();
// 4 bytes timestamp, 32 bytes tag, 32 bytes key
for (auto it: m_Tags)
{
if (ts < it.first.creationTime + INCOMING_TAGS_EXPIRATION_TIMEOUT)
{
f.write ((char *)&it.first.creationTime, 4);
f.write ((char *)it.first.data (), 32);
f.write ((char *)it.second->GetKey ().data (), 32);
}
}
}
void GarlicDestination::LoadTags ()
{
std::string ident = GetIdentHash().ToBase32();
std::string path = i2p::fs::DataDirPath("tags", (ident + ".tags"));
uint32_t ts = i2p::util::GetSecondsSinceEpoch ();
if (ts < i2p::fs::GetLastUpdateTime (path) + INCOMING_TAGS_EXPIRATION_TIMEOUT)
{
// might contain non-expired tags
std::ifstream f (path, std::ifstream::binary);
if (f)
{
std::map<i2p::crypto::AESKey, std::shared_ptr<AESDecryption> > keys;
// 4 bytes timestamp, 32 bytes tag, 32 bytes key
while (!f.eof ())
{
uint32_t t;
uint8_t tag[32], key[32];
f.read ((char *)&t, 4); if (f.eof ()) break;
if (ts < t + INCOMING_TAGS_EXPIRATION_TIMEOUT)
{
f.read ((char *)tag, 32);
f.read ((char *)key, 32);
}