Archives
/
i2pd
mirror of https://github.com/PurpleI2P/i2pd
2
0
Fork 0
Code Issues Projects Releases Wiki Activity

session tag for ECIESx25519 sessions

Browse Source
pull/1474/head
orignal 4 years ago
parent ccec3376ba
commit 6142e93252
4 changed files with 80 additions and 29 deletions
Show Stats Download Patch File Download Diff File

51
libi2pd/ECIESX25519AEADRatchetSession.cpp
Unescape Escape View File

@ -18,20 +18,20 @@ namespace garlic
uint8_t keydata[64];
i2p::crypto::HKDF (rootKey, k, 32, "KDFDHRatchetStep", keydata); // keydata = HKDF(rootKey, k, "KDFDHRatchetStep", 64)
// nextRootKey = keydata[0:31]
i2p::crypto::HKDF (keydata + 32, nullptr, 0, "TagAndKeyGenKeys", m_CK);
// ck = [sessTag_ck, symmKey_ck] = HKDF(keydata[32:63], ZEROLEN, "TagAndKeyGenKeys", 64)
i2p::crypto::HKDF (keydata + 32, nullptr, 0, "TagAndKeyGenKeys", m_KeyData.buf);
// [sessTag_ck, symmKey_ck] = HKDF(keydata[32:63], ZEROLEN, "TagAndKeyGenKeys", 64)
}
void RatchetTagSet::NextSessionTagRatchet ()
{
i2p::crypto::HKDF (m_CK, nullptr, 0, "STInitialization", m_CK); // [ck, sesstag_constant] = HKDF(sessTag_ck, ZEROLEN, "STInitialization", 64)
memcpy (m_SessTagConstant, m_CK + 32, 32);
i2p::crypto::HKDF (m_KeyData.GetSessTagCK (), nullptr, 0, "STInitialization", m_KeyData.buf); // [sessTag_ck, sesstag_constant] = HKDF(sessTag_ck, ZEROLEN, "STInitialization", 64)
memcpy (m_SessTagConstant, m_KeyData.GetSessTagConstant (), 32);
}
const uint8_t * RatchetTagSet::GetNextSessionTag ()
uint64_t RatchetTagSet::GetNextSessionTag ()
{
i2p::crypto::HKDF (m_CK, m_SessTagConstant, 32, "SessionTagKeyGen", m_CK); // [ck, tag] = HKDF(sessTag_chainkey, SESSTAG_CONSTANT, "SessionTagKeyGen", 64)
return m_CK + 32;
i2p::crypto::HKDF (m_KeyData.GetSessTagCK (), m_SessTagConstant, 32, "SessionTagKeyGen", m_KeyData.buf); // [sessTag_ck, tag] = HKDF(sessTag_chainkey, SESSTAG_CONSTANT, "SessionTagKeyGen", 64)
return m_KeyData.GetTag ();
}
@ -60,7 +60,7 @@ namespace garlic
bool ECIESX25519AEADRatchetSession::GenerateEphemeralKeysAndEncode (uint8_t * buf)
{
for (int i = 0; i < 5; i++)
for (int i = 0; i < 10; i++)
{
m_EphemeralKeys.GenerateKeys ();
if (i2p::crypto::GetElligator ()->Encode (m_EphemeralKeys.GetPublicKey (), buf))
@ -69,6 +69,17 @@ namespace garlic
return false;
}
uint64_t ECIESX25519AEADRatchetSession::CreateNewSessionTag () const
{
uint8_t tagsetKey[32];
i2p::crypto::HKDF (m_CK, nullptr, 0, "SessionReplyTags", tagsetKey, 32); // tagsetKey = HKDF(chainKey, ZEROLEN, "SessionReplyTags", 32)
// Session Tag Ratchet
RatchetTagSet tagsetNsr;
tagsetNsr.DHInitialize (m_CK, tagsetKey); // tagset_nsr = DH_INITIALIZE(chainKey, tagsetKey)
tagsetNsr.NextSessionTagRatchet ();
return tagsetNsr.GetNextSessionTag ();
}
bool ECIESX25519AEADRatchetSession::NewIncomingSession (const uint8_t * buf, size_t len, CloveHandler handleClove)
{
if (!GetOwner ()) return false;
@ -199,24 +210,20 @@ namespace garlic
return false;
}
MixHash (out + offset, 16); // h = SHA256(h || ciphertext)
if (GetOwner ())
GetOwner ()->AddECIESx25519SessionTag (CreateNewSessionTag (), shared_from_this ());
return true;
}
bool ECIESX25519AEADRatchetSession::NewSessionReplyMessage (const uint8_t * payload, size_t len, uint8_t * out, size_t outLen)
{
// we are Bob
uint8_t tagsetKey[32];
i2p::crypto::HKDF (m_CK, nullptr, 0, "SessionReplyTags", tagsetKey, 32); // tagsetKey = HKDF(chainKey, ZEROLEN, "SessionReplyTags", 32)
// Session Tag Ratchet
RatchetTagSet tagsetNsr;
tagsetNsr.DHInitialize (m_CK, tagsetKey); // tagset_nsr = DH_INITIALIZE(chainKey, tagsetKey)
tagsetNsr.NextSessionTagRatchet ();
auto tag = tagsetNsr.GetNextSessionTag ();
uint64_t tag = CreateNewSessionTag ();
size_t offset = 0;
memcpy (out + offset, tag, 8);
memcpy (out + offset, &tag, 8);
offset += 8;
if (!GenerateEphemeralKeysAndEncode (out + offset)) // bepk
{
@ -225,7 +232,7 @@ namespace garlic
}
offset += 32;
// KDF for Reply Key Section
MixHash (tag, 8); // h = SHA256(h || tag)
MixHash ((const uint8_t *)&tag, 8); // h = SHA256(h || tag)
MixHash (m_EphemeralKeys.GetPublicKey (), 32); // h = SHA256(h || bepk)
uint8_t sharedSecret[32];
m_EphemeralKeys.Agree (m_RemoteStaticKey, sharedSecret); // sharedSecret = x25519(besk, aepk)
@ -257,6 +264,12 @@ namespace garlic
return true;
}
bool ECIESX25519AEADRatchetSession::NewOutgoingSessionReply (const uint8_t * buf, size_t len, CloveHandler handleClove)
{
// TODO
return true;
}
std::shared_ptr<I2NPMessage> ECIESX25519AEADRatchetSession::WrapSingleMessage (std::shared_ptr<const I2NPMessage> msg)
{
auto m = NewI2NPMessage ();

21
libi2pd/ECIESX25519AEADRatchetSession.h
Unescape Escape View File

@ -4,6 +4,7 @@
#include <string.h>
#include <inttypes.h>
#include <functional>
#include <memory>
#include <vector>
#include "Identity.h"
#include "Crypto.h"
@ -19,11 +20,21 @@ namespace garlic
void DHInitialize (const uint8_t * rootKey, const uint8_t * k);
void NextSessionTagRatchet ();
const uint8_t * GetNextSessionTag ();
uint64_t GetNextSessionTag ();
private:
uint8_t m_CK[64], m_SessTagConstant[32];
union
{
uint64_t ll[8];
uint8_t buf[64];
const uint8_t * GetSessTagCK () const { return buf; }; // sessTag_chainKey = keydata[0:31]
const uint8_t * GetSessTagConstant () const { return buf + 32; }; // SESSTAG_CONSTANT = keydata[32:63]
uint64_t GetTag () const { return ll[4]; }; // tag = keydata[32:39]
} m_KeyData;
uint8_t m_SessTagConstant[32];
};
enum ECIESx25519BlockType
@ -37,7 +48,7 @@ namespace garlic
eECIESx25519BlkPadding = 254
};
class ECIESX25519AEADRatchetSession: public GarlicRoutingSession
class ECIESX25519AEADRatchetSession: public GarlicRoutingSession, public std::enable_shared_from_this<ECIESX25519AEADRatchetSession>
{
enum SessionState
{
@ -55,6 +66,7 @@ namespace garlic
std::shared_ptr<I2NPMessage> WrapSingleMessage (std::shared_ptr<const I2NPMessage> msg);
bool NewIncomingSession (const uint8_t * buf, size_t len, CloveHandler handleClove);
bool NewOutgoingSessionReply (const uint8_t * buf, size_t len, CloveHandler handleClove);
const uint8_t * GetRemoteStaticKey () const { return m_RemoteStaticKey; }
void SetRemoteStaticKey (const uint8_t * key) { memcpy (m_RemoteStaticKey, key, 32); }
@ -62,6 +74,7 @@ namespace garlic
void MixHash (const uint8_t * buf, size_t len);
bool GenerateEphemeralKeysAndEncode (uint8_t * buf); // buf is 32 bytes
uint64_t CreateNewSessionTag () const;
void HandlePayload (const uint8_t * buf, size_t len, CloveHandler& handleClove);

33
libi2pd/Garlic.cpp
Unescape Escape View File

@ -861,14 +861,32 @@ namespace garlic
void GarlicDestination::HandleECIESx25519 (const uint8_t * buf, size_t len)
{
auto session = std::make_shared<ECIESX25519AEADRatchetSession> (this);
if (session->NewIncomingSession (buf, len, std::bind (&GarlicDestination::HandleECIESx25519GarlicClove,
this, std::placeholders::_1, std::placeholders::_2)))
auto handleClove = std::bind (&GarlicDestination::HandleECIESx25519GarlicClove,
this, std::placeholders::_1, std::placeholders::_2);
uint64_t tag;
memcpy (&tag, buf, 8);
auto it = m_ECIESx25519Tags.find (tag);
if (it != m_ECIESx25519Tags.end ())
{
m_ECIESx25519Sessions.emplace (session->GetRemoteStaticKey (), session);
// TODO
auto session = it->second;
if (!session->NewOutgoingSessionReply (buf, len, handleClove))
{
LogPrint (eLogError, "Garlic: can't decrypt ECIES-X25519-AEAD-Ratchet new session reply");
m_ECIESx25519Tags.erase (tag);
m_ECIESx25519Sessions.erase (session->GetRemoteStaticKey ());
}
}
else
LogPrint (eLogError, "Garlic: can't decrypt ECIES-X25519-AEAD-Ratchet new session");
{
auto session = std::make_shared<ECIESX25519AEADRatchetSession> (this);
if (session->NewIncomingSession (buf, len, handleClove))
{
m_ECIESx25519Sessions.emplace (session->GetRemoteStaticKey (), session);
}
else
LogPrint (eLogError, "Garlic: can't decrypt ECIES-X25519-AEAD-Ratchet new session");
}
}
void GarlicDestination::HandleECIESx25519GarlicClove (const uint8_t * buf, size_t len)
@ -926,5 +944,10 @@ namespace garlic
LogPrint (eLogWarning, "Garlic: unexpected delivery type ", (int)deliveryType);
}
}
void GarlicDestination::AddECIESx25519SessionTag (uint64_t tag, ECIESX25519AEADRatchetSessionPtr session)
{
m_ECIESx25519Tags.emplace (tag, session);
}
}
}

4
libi2pd/Garlic.h
Unescape Escape View File

@ -217,6 +217,7 @@ namespace garlic
void AddSessionKey (const uint8_t * key, const uint8_t * tag); // one tag
virtual bool SubmitSessionKey (const uint8_t * key, const uint8_t * tag); // from different thread
void DeliveryStatusSent (ElGamalAESSessionPtr session, uint32_t msgID);
void AddECIESx25519SessionTag (uint64_t tag, ECIESX25519AEADRatchetSessionPtr session);
virtual void ProcessGarlicMessage (std::shared_ptr<I2NPMessage> msg);
virtual void ProcessDeliveryStatusMessage (std::shared_ptr<I2NPMessage> msg);
@ -252,9 +253,10 @@ namespace garlic
int m_NumTags;
std::mutex m_SessionsMutex;
std::map<i2p::data::IdentHash, ElGamalAESSessionPtr> m_Sessions;
std::map<i2p::data::Tag<32>, ECIESX25519AEADRatchetSessionPtr > m_ECIESx25519Sessions; // static key -> session
std::map<i2p::data::Tag<32>, ECIESX25519AEADRatchetSessionPtr> m_ECIESx25519Sessions; // static key -> session
// incoming
std::map<SessionTag, std::shared_ptr<AESDecryption> > m_Tags;
std::map<uint64_t, ECIESX25519AEADRatchetSessionPtr> m_ECIESx25519Tags; // session tag -> session
// DeliveryStatus
std::mutex m_DeliveryStatusSessionsMutex;
std::map<uint32_t, ElGamalAESSessionPtr> m_DeliveryStatusSessions; // msgID -> session

Write Preview
Loading…
Cancel
Save