decrypt garlic on ECIES router

This commit is contained in:
orignal 2020-11-05 15:27:37 -05:00
parent 1740715c00
commit 6362a7bba5
3 changed files with 24 additions and 21 deletions

View File

@ -176,15 +176,6 @@ namespace garlic
memcpy (m_H, hh, 32);
}
void ECIESX25519AEADRatchetSession::MixHash (const uint8_t * buf, size_t len)
{
SHA256_CTX ctx;
SHA256_Init (&ctx);
SHA256_Update (&ctx, m_H, 32);
SHA256_Update (&ctx, buf, len);
SHA256_Final (m_H, &ctx);
}
void ECIESX25519AEADRatchetSession::CreateNonce (uint64_t seqn, uint8_t * nonce)
{
memset (nonce, 0, 4);
@ -257,7 +248,7 @@ namespace garlic
uint8_t sharedSecret[32];
GetOwner ()->Decrypt (m_Aepk, sharedSecret, nullptr, i2p::data::CRYPTO_KEY_TYPE_ECIES_X25519_AEAD_RATCHET); // x25519(bsk, aepk)
i2p::crypto::HKDF (m_CK, sharedSecret, 32, "", m_CK); // [chainKey, key] = HKDF(chainKey, sharedSecret, "", 64)
MixKey (sharedSecret);
// decrypt flags/static
uint8_t nonce[12], fs[32];
@ -277,7 +268,7 @@ namespace garlic
// static key, fs is apk
memcpy (m_RemoteStaticKey, fs, 32);
GetOwner ()->Decrypt (fs, sharedSecret, nullptr, i2p::data::CRYPTO_KEY_TYPE_ECIES_X25519_AEAD_RATCHET); // x25519(bsk, apk)
i2p::crypto::HKDF (m_CK, sharedSecret, 32, "", m_CK); // [chainKey, key] = HKDF(chainKey, sharedSecret, "", 64)
MixKey (sharedSecret);
}
else // all zeros flags
CreateNonce (1, nonce);
@ -289,10 +280,13 @@ namespace garlic
LogPrint (eLogWarning, "Garlic: Payload section AEAD verification failed");
return false;
}
if (isStatic) MixHash (buf, len); // h = SHA256(h || ciphertext)
m_State = eSessionStateNewSessionReceived;
GetOwner ()->AddECIESx25519Session (m_RemoteStaticKey, shared_from_this ());
m_State = eSessionStateNewSessionReceived;
if (isStatic)
{
MixHash (buf, len); // h = SHA256(h || ciphertext)
GetOwner ()->AddECIESx25519Session (m_RemoteStaticKey, shared_from_this ());
}
HandlePayload (payload.data (), len - 16, nullptr, 0);
return true;
@ -469,7 +463,7 @@ namespace garlic
MixHash (m_EphemeralKeys->GetPublicKey (), 32); // h = SHA256(h || aepk)
uint8_t sharedSecret[32];
m_EphemeralKeys->Agree (m_RemoteStaticKey, sharedSecret); // x25519(aesk, bpk)
i2p::crypto::HKDF (m_CK, sharedSecret, 32, "", m_CK); // [chainKey, key] = HKDF(chainKey, sharedSecret, "", 64)
MixKey (sharedSecret);
// encrypt static key section
uint8_t nonce[12];
CreateNonce (0, nonce);
@ -482,7 +476,7 @@ namespace garlic
offset += 48;
// KDF2
GetOwner ()->Decrypt (m_RemoteStaticKey, sharedSecret, nullptr, i2p::data::CRYPTO_KEY_TYPE_ECIES_X25519_AEAD_RATCHET); // x25519 (ask, bpk)
i2p::crypto::HKDF (m_CK, sharedSecret, 32, "", m_CK); // [chainKey, key] = HKDF(chainKey, sharedSecret, "", 64)
MixKey (sharedSecret);
// encrypt payload
if (!i2p::crypto::AEADChaCha20Poly1305 (payload, len, m_H, 32, m_CK + 32, nonce, out + offset, len + 16, true)) // encrypt
{
@ -520,9 +514,9 @@ namespace garlic
MixHash (m_EphemeralKeys->GetPublicKey (), 32); // h = SHA256(h || bepk)
uint8_t sharedSecret[32];
m_EphemeralKeys->Agree (m_Aepk, sharedSecret); // sharedSecret = x25519(besk, aepk)
i2p::crypto::HKDF (m_CK, sharedSecret, 32, "", m_CK, 32); // chainKey = HKDF(chainKey, sharedSecret, "", 32)
MixKey (sharedSecret);
m_EphemeralKeys->Agree (m_RemoteStaticKey, sharedSecret); // sharedSecret = x25519(besk, apk)
i2p::crypto::HKDF (m_CK, sharedSecret, 32, "", m_CK); // [chainKey, key] = HKDF(chainKey, sharedSecret, "", 64)
MixKey (sharedSecret);
uint8_t nonce[12];
CreateNonce (0, nonce);
// calculate hash for zero length
@ -607,9 +601,9 @@ namespace garlic
{
// only fist time, we assume ephemeral keys the same
m_EphemeralKeys->Agree (bepk, sharedSecret); // sharedSecret = x25519(aesk, bepk)
i2p::crypto::HKDF (m_CK, sharedSecret, 32, "", m_CK, 32); // chainKey = HKDF(chainKey, sharedSecret, "", 32)
MixKey (sharedSecret);
GetOwner ()->Decrypt (bepk, sharedSecret, nullptr, i2p::data::CRYPTO_KEY_TYPE_ECIES_X25519_AEAD_RATCHET); // x25519 (ask, bepk)
i2p::crypto::HKDF (m_CK, sharedSecret, 32, "", m_CK); // [chainKey, key] = HKDF(chainKey, sharedSecret, "", 64)
MixKey (sharedSecret);
}
uint8_t nonce[12];
CreateNonce (0, nonce);

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@ -653,6 +653,15 @@ namespace i2p
i2p::HandleI2NPMessage (CreateI2NPMessage (buf, GetI2NPMessageLength (buf, len)));
}
bool RouterContext::HandleCloveI2NPMessage (I2NPMessageType typeID, const uint8_t * payload, size_t len)
{
auto msg = CreateI2NPMessage (typeID, payload, len);
if (!msg) return false;
i2p::HandleI2NPMessage (msg);
return true;
}
void RouterContext::ProcessGarlicMessage (std::shared_ptr<I2NPMessage> msg)
{
std::unique_lock<std::mutex> l(m_GarlicMutex);

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@ -135,7 +135,7 @@ namespace i2p
// implements GarlicDestination
void HandleI2NPMessage (const uint8_t * buf, size_t len);
bool HandleCloveI2NPMessage (I2NPMessageType typeID, const uint8_t * payload, size_t len) { return false; }; // not implemented
bool HandleCloveI2NPMessage (I2NPMessageType typeID, const uint8_t * payload, size_t len);
private: