mirror of
https://github.com/PurpleI2P/i2pd.git
synced 2024-11-17 21:26:04 +00:00
630 lines
24 KiB
C++
630 lines
24 KiB
C++
#include <string.h>
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#include <openssl/sha.h>
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#include "Log.h"
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#include "Crypto.h"
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#include "Elligator.h"
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#include "Tag.h"
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#include "I2PEndian.h"
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#include "Timestamp.h"
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#include "Tunnel.h"
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#include "TunnelPool.h"
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#include "ECIESX25519AEADRatchetSession.h"
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namespace i2p
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{
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namespace garlic
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{
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void RatchetTagSet::DHInitialize (const uint8_t * rootKey, const uint8_t * k)
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{
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// DH_INITIALIZE(rootKey, k)
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uint8_t keydata[64];
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i2p::crypto::HKDF (rootKey, k, 32, "KDFDHRatchetStep", keydata); // keydata = HKDF(rootKey, k, "KDFDHRatchetStep", 64)
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// nextRootKey = keydata[0:31]
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i2p::crypto::HKDF (keydata + 32, nullptr, 0, "TagAndKeyGenKeys", m_KeyData.buf);
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// [sessTag_ck, symmKey_ck] = HKDF(keydata[32:63], ZEROLEN, "TagAndKeyGenKeys", 64)
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memcpy (m_SymmKeyCK, m_KeyData.buf + 32, 32);
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m_NextSymmKeyIndex = 0;
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}
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void RatchetTagSet::NextSessionTagRatchet ()
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{
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i2p::crypto::HKDF (m_KeyData.GetSessTagCK (), nullptr, 0, "STInitialization", m_KeyData.buf); // [sessTag_ck, sesstag_constant] = HKDF(sessTag_ck, ZEROLEN, "STInitialization", 64)
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memcpy (m_SessTagConstant, m_KeyData.GetSessTagConstant (), 32);
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m_NextIndex = 0;
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}
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uint64_t RatchetTagSet::GetNextSessionTag ()
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{
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i2p::crypto::HKDF (m_KeyData.GetSessTagCK (), m_SessTagConstant, 32, "SessionTagKeyGen", m_KeyData.buf); // [sessTag_ck, tag] = HKDF(sessTag_chainkey, SESSTAG_CONSTANT, "SessionTagKeyGen", 64)
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m_NextIndex++;
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if (m_NextIndex >= 65535) m_NextIndex = 0; // TODO: dirty hack, should create new tagset
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return m_KeyData.GetTag ();
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}
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void RatchetTagSet::GetSymmKey (int index, uint8_t * key)
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{
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if (m_NextSymmKeyIndex > 0 && index >= m_NextSymmKeyIndex)
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{
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auto num = index + 1 - m_NextSymmKeyIndex;
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for (int i = 0; i < num; i++)
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i2p::crypto::HKDF (m_CurrentSymmKeyCK, nullptr, 0, "SymmetricRatchet", m_CurrentSymmKeyCK);
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m_NextSymmKeyIndex += num;
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memcpy (key, m_CurrentSymmKeyCK + 32, 32);
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}
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else
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CalculateSymmKeyCK (index, key);
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}
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void RatchetTagSet::CalculateSymmKeyCK (int index, uint8_t * key)
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{
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// TODO: store intermediate keys
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uint8_t currentSymmKeyCK[64];
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i2p::crypto::HKDF (m_SymmKeyCK, nullptr, 0, "SymmetricRatchet", currentSymmKeyCK); // keydata_0 = HKDF(symmKey_ck, SYMMKEY_CONSTANT, "SymmetricRatchet", 64)
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for (int i = 0; i < index; i++)
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i2p::crypto::HKDF (currentSymmKeyCK, nullptr, 0, "SymmetricRatchet", currentSymmKeyCK); // keydata_n = HKDF(symmKey_chainKey_(n-1), SYMMKEY_CONSTANT, "SymmetricRatchet", 64)
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memcpy (key, currentSymmKeyCK + 32, 32);
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}
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ECIESX25519AEADRatchetSession::ECIESX25519AEADRatchetSession (GarlicDestination * owner):
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GarlicRoutingSession (owner, true)
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{
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ResetKeys ();
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}
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ECIESX25519AEADRatchetSession::~ECIESX25519AEADRatchetSession ()
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{
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}
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void ECIESX25519AEADRatchetSession::ResetKeys ()
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{
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// TODO : use precalculated hashes
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static const char protocolName[41] = "Noise_IKelg2+hs2_25519_ChaChaPoly_SHA256"; // 40 bytes
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SHA256 ((const uint8_t *)protocolName, 40, m_H);
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memcpy (m_CK, m_H, 32);
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SHA256 (m_H, 32, m_H);
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}
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void ECIESX25519AEADRatchetSession::MixHash (const uint8_t * buf, size_t len)
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{
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SHA256_CTX ctx;
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SHA256_Init (&ctx);
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SHA256_Update (&ctx, m_H, 32);
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SHA256_Update (&ctx, buf, len);
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SHA256_Final (m_H, &ctx);
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}
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void ECIESX25519AEADRatchetSession::CreateNonce (uint64_t seqn, uint8_t * nonce)
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{
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memset (nonce, 0, 4);
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htole64buf (nonce + 4, seqn);
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}
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bool ECIESX25519AEADRatchetSession::GenerateEphemeralKeysAndEncode (uint8_t * buf)
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{
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for (int i = 0; i < 10; i++)
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{
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m_EphemeralKeys.GenerateKeys ();
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if (i2p::crypto::GetElligator ()->Encode (m_EphemeralKeys.GetPublicKey (), buf))
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return true; // success
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}
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return false;
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}
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uint64_t ECIESX25519AEADRatchetSession::CreateNewSessionTag () const
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{
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uint8_t tagsetKey[32];
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i2p::crypto::HKDF (m_CK, nullptr, 0, "SessionReplyTags", tagsetKey, 32); // tagsetKey = HKDF(chainKey, ZEROLEN, "SessionReplyTags", 32)
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// Session Tag Ratchet
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RatchetTagSet tagsetNsr;
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tagsetNsr.DHInitialize (m_CK, tagsetKey); // tagset_nsr = DH_INITIALIZE(chainKey, tagsetKey)
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tagsetNsr.NextSessionTagRatchet ();
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return tagsetNsr.GetNextSessionTag ();
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}
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bool ECIESX25519AEADRatchetSession::HandleNewIncomingSession (const uint8_t * buf, size_t len)
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{
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if (!GetOwner ()) return false;
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// we are Bob
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// KDF1
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MixHash (GetOwner ()->GetEncryptionPublicKey (i2p::data::CRYPTO_KEY_TYPE_ECIES_X25519_AEAD_RARCHET), 32); // h = SHA256(h || bpk)
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if (!i2p::crypto::GetElligator ()->Decode (buf, m_Aepk))
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{
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LogPrint (eLogError, "Garlic: Can't decode elligator");
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return false;
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}
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buf += 32; len -= 32;
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MixHash (m_Aepk, 32); // h = SHA256(h || aepk)
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uint8_t sharedSecret[32];
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GetOwner ()->Decrypt (m_Aepk, sharedSecret, nullptr, i2p::data::CRYPTO_KEY_TYPE_ECIES_X25519_AEAD_RARCHET); // x25519(bsk, aepk)
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i2p::crypto::HKDF (m_CK, sharedSecret, 32, "", m_CK); // [chainKey, key] = HKDF(chainKey, sharedSecret, "", 64)
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// decrypt flags/static
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uint8_t nonce[12], fs[32];
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CreateNonce (0, nonce);
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if (!i2p::crypto::AEADChaCha20Poly1305 (buf, 32, m_H, 32, m_CK + 32, nonce, fs, 32, false)) // decrypt
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{
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LogPrint (eLogWarning, "Garlic: Flags/static section AEAD verification failed ");
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return false;
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}
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MixHash (buf, 48); // h = SHA256(h || ciphertext)
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buf += 48; len -= 48; // 32 data + 16 poly
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// decrypt payload
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std::vector<uint8_t> payload (len - 16);
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// KDF2 for payload
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bool isStatic = !i2p::data::Tag<32> (fs).IsZero ();
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if (isStatic)
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{
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// static key, fs is apk
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memcpy (m_RemoteStaticKey, fs, 32);
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GetOwner ()->Decrypt (fs, sharedSecret, nullptr, i2p::data::CRYPTO_KEY_TYPE_ECIES_X25519_AEAD_RARCHET); // x25519(bsk, apk)
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i2p::crypto::HKDF (m_CK, sharedSecret, 32, "", m_CK); // [chainKey, key] = HKDF(chainKey, sharedSecret, "", 64)
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}
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else // all zeros flags
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CreateNonce (1, nonce);
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if (!i2p::crypto::AEADChaCha20Poly1305 (buf, len - 16, m_H, 32, m_CK + 32, nonce, payload.data (), len - 16, false)) // decrypt
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{
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LogPrint (eLogWarning, "Garlic: Payload section AEAD verification failed");
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return false;
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}
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if (isStatic) MixHash (buf, len); // h = SHA256(h || ciphertext)
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m_State = eSessionStateNewSessionReceived;
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GetOwner ()->AddECIESx25519Session (m_RemoteStaticKey, shared_from_this ());
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HandlePayload (payload.data (), len - 16);
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return true;
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}
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void ECIESX25519AEADRatchetSession::HandlePayload (const uint8_t * buf, size_t len, int index)
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{
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size_t offset = 0;
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while (offset < len)
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{
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uint8_t blk = buf[offset];
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offset++;
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auto size = bufbe16toh (buf + offset);
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offset += 2;
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LogPrint (eLogDebug, "Garlic: Block type ", (int)blk, " of size ", size);
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if (size > len)
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{
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LogPrint (eLogError, "Garlic: Unexpected block length ", size);
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break;
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}
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switch (blk)
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{
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case eECIESx25519BlkGalicClove:
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GetOwner ()->HandleECIESx25519GarlicClove (buf + offset, size);
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break;
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case eECIESx25519BlkDateTime:
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LogPrint (eLogDebug, "Garlic: datetime");
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break;
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case eECIESx25519BlkOptions:
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LogPrint (eLogDebug, "Garlic: options");
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break;
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case eECIESx25519BlkPadding:
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LogPrint (eLogDebug, "Garlic: padding");
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break;
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case eECIESx25519BlkAckRequest:
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{
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LogPrint (eLogDebug, "Garlic: ack request");
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m_AckRequests.push_back ({0, index}); // TODO: use actual tagsetid
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break;
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}
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default:
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LogPrint (eLogWarning, "Garlic: Unknown block type ", (int)blk);
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}
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offset += size;
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}
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}
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bool ECIESX25519AEADRatchetSession::NewOutgoingSessionMessage (const uint8_t * payload, size_t len, uint8_t * out, size_t outLen)
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{
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ResetKeys ();
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// we are Alice, bpk is m_RemoteStaticKey
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size_t offset = 0;
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if (!GenerateEphemeralKeysAndEncode (out + offset))
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{
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LogPrint (eLogError, "Garlic: Can't encode elligator");
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return false;
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}
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offset += 32;
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// KDF1
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MixHash (m_RemoteStaticKey, 32); // h = SHA256(h || bpk)
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MixHash (m_EphemeralKeys.GetPublicKey (), 32); // h = SHA256(h || aepk)
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uint8_t sharedSecret[32];
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m_EphemeralKeys.Agree (m_RemoteStaticKey, sharedSecret); // x25519(aesk, bpk)
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i2p::crypto::HKDF (m_CK, sharedSecret, 32, "", m_CK); // [chainKey, key] = HKDF(chainKey, sharedSecret, "", 64)
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// encrypt static key section
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uint8_t nonce[12];
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CreateNonce (0, nonce);
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if (!i2p::crypto::AEADChaCha20Poly1305 (GetOwner ()->GetEncryptionPublicKey (i2p::data::CRYPTO_KEY_TYPE_ECIES_X25519_AEAD_RARCHET), 32, m_H, 32, m_CK + 32, nonce, out + offset, 48, true)) // encrypt
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{
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LogPrint (eLogWarning, "Garlic: Static section AEAD encryption failed ");
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return false;
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}
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MixHash (out + offset, 48); // h = SHA256(h || ciphertext)
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offset += 48;
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// KDF2
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GetOwner ()->Decrypt (m_RemoteStaticKey, sharedSecret, nullptr, i2p::data::CRYPTO_KEY_TYPE_ECIES_X25519_AEAD_RARCHET); // x25519 (ask, bpk)
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i2p::crypto::HKDF (m_CK, sharedSecret, 32, "", m_CK); // [chainKey, key] = HKDF(chainKey, sharedSecret, "", 64)
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// encrypt payload
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if (!i2p::crypto::AEADChaCha20Poly1305 (payload, len, m_H, 32, m_CK + 32, nonce, out + offset, len + 16, true)) // encrypt
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{
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LogPrint (eLogWarning, "Garlic: Payload section AEAD encryption failed");
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return false;
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}
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MixHash (out + offset, len + 16); // h = SHA256(h || ciphertext)
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m_State = eSessionStateNewSessionSent;
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if (GetOwner ())
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GetOwner ()->AddECIESx25519SessionTag (0, CreateNewSessionTag (), shared_from_this ());
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return true;
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}
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bool ECIESX25519AEADRatchetSession::NewSessionReplyMessage (const uint8_t * payload, size_t len, uint8_t * out, size_t outLen)
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{
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// we are Bob
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uint64_t tag = CreateNewSessionTag ();
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size_t offset = 0;
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memcpy (out + offset, &tag, 8);
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offset += 8;
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if (!GenerateEphemeralKeysAndEncode (out + offset)) // bepk
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{
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LogPrint (eLogError, "Garlic: Can't encode elligator");
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return false;
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}
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offset += 32;
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// KDF for Reply Key Section
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MixHash ((const uint8_t *)&tag, 8); // h = SHA256(h || tag)
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MixHash (m_EphemeralKeys.GetPublicKey (), 32); // h = SHA256(h || bepk)
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uint8_t sharedSecret[32];
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m_EphemeralKeys.Agree (m_Aepk, sharedSecret); // sharedSecret = x25519(besk, aepk)
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i2p::crypto::HKDF (m_CK, sharedSecret, 32, "", m_CK, 32); // chainKey = HKDF(chainKey, sharedSecret, "", 32)
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m_EphemeralKeys.Agree (m_RemoteStaticKey, sharedSecret); // sharedSecret = x25519(besk, apk)
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i2p::crypto::HKDF (m_CK, sharedSecret, 32, "", m_CK); // [chainKey, key] = HKDF(chainKey, sharedSecret, "", 64)
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uint8_t nonce[12];
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CreateNonce (0, nonce);
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// calulate hash for zero length
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if (!i2p::crypto::AEADChaCha20Poly1305 (sharedSecret /* can be anything */, 0, m_H, 32, m_CK + 32, nonce, out + offset, 16, true)) // encrypt, ciphertext = ENCRYPT(k, n, ZEROLEN, ad)
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{
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LogPrint (eLogWarning, "Garlic: Reply key section AEAD encryption failed");
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return false;
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}
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MixHash (out + offset, 16); // h = SHA256(h || ciphertext)
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offset += 16;
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memcpy (m_NSRHeader, out, 56); // for possible next NSR
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// KDF for payload
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uint8_t keydata[64];
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i2p::crypto::HKDF (m_CK, nullptr, 0, "", keydata); // keydata = HKDF(chainKey, ZEROLEN, "", 64)
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// k_ab = keydata[0:31], k_ba = keydata[32:63]
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m_ReceiveTagset.DHInitialize (m_CK, keydata); // tagset_ab = DH_INITIALIZE(chainKey, k_ab)
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m_ReceiveTagset.NextSessionTagRatchet ();
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m_SendTagset.DHInitialize (m_CK, keydata + 32); // tagset_ba = DH_INITIALIZE(chainKey, k_ba)
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m_SendTagset.NextSessionTagRatchet ();
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GenerateMoreReceiveTags (GetOwner ()->GetNumTags ());
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i2p::crypto::HKDF (keydata + 32, nullptr, 0, "AttachPayloadKDF", m_NSRKey, 32); // k = HKDF(k_ba, ZEROLEN, "AttachPayloadKDF", 32)
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// encrypt payload
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if (!i2p::crypto::AEADChaCha20Poly1305 (payload, len, m_H, 32, m_NSRKey, nonce, out + offset, len + 16, true)) // encrypt
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{
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LogPrint (eLogWarning, "Garlic: NSR payload section AEAD encryption failed");
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return false;
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}
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m_State = eSessionStateNewSessionReplySent;
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return true;
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}
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bool ECIESX25519AEADRatchetSession::NextNewSessionReplyMessage (const uint8_t * payload, size_t len, uint8_t * out, size_t outLen)
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{
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// we are Bob and sent NSR already
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memcpy (out, m_NSRHeader, 56);
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uint8_t nonce[12];
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CreateNonce (0, nonce);
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// encrypt payload
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if (!i2p::crypto::AEADChaCha20Poly1305 (payload, len, m_H, 32, m_NSRKey, nonce, out + 56, len + 16, true)) // encrypt
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{
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LogPrint (eLogWarning, "Garlic: Next NSR payload section AEAD encryption failed");
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return false;
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}
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return true;
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}
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bool ECIESX25519AEADRatchetSession::HandleNewOutgoingSessionReply (const uint8_t * buf, size_t len)
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{
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// we are Alice
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LogPrint (eLogDebug, "Garlic: reply received");
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const uint8_t * tag = buf;
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buf += 8; len -= 8; // tag
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uint8_t bepk[32]; // Bob's ephemeral key
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if (!i2p::crypto::GetElligator ()->Decode (buf, bepk))
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{
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LogPrint (eLogError, "Garlic: Can't decode elligator");
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return false;
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}
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buf += 32; len -= 32;
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// KDF for Reply Key Section
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MixHash (tag, 8); // h = SHA256(h || tag)
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MixHash (bepk, 32); // h = SHA256(h || bepk)
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uint8_t sharedSecret[32];
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m_EphemeralKeys.Agree (bepk, sharedSecret); // sharedSecret = x25519(aesk, bepk)
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i2p::crypto::HKDF (m_CK, sharedSecret, 32, "", m_CK, 32); // chainKey = HKDF(chainKey, sharedSecret, "", 32)
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GetOwner ()->Decrypt (bepk, sharedSecret, nullptr, i2p::data::CRYPTO_KEY_TYPE_ECIES_X25519_AEAD_RARCHET); // x25519 (ask, bepk)
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i2p::crypto::HKDF (m_CK, sharedSecret, 32, "", m_CK); // [chainKey, key] = HKDF(chainKey, sharedSecret, "", 64)
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uint8_t nonce[12];
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CreateNonce (0, nonce);
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// calulate hash for zero length
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if (!i2p::crypto::AEADChaCha20Poly1305 (buf, 0, m_H, 32, m_CK + 32, nonce, sharedSecret/* can be anyting */, 0, false)) // decrypt, DECRYPT(k, n, ZEROLEN, ad) verification only
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{
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LogPrint (eLogWarning, "Garlic: Reply key section AEAD decryption failed");
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return false;
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}
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MixHash (buf, 16); // h = SHA256(h || ciphertext)
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buf += 16; len -= 16;
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// KDF for payload
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uint8_t keydata[64];
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i2p::crypto::HKDF (m_CK, nullptr, 0, "", keydata); // keydata = HKDF(chainKey, ZEROLEN, "", 64)
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// k_ab = keydata[0:31], k_ba = keydata[32:63]
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m_SendTagset.DHInitialize (m_CK, keydata); // tagset_ab = DH_INITIALIZE(chainKey, k_ab)
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m_SendTagset.NextSessionTagRatchet ();
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m_ReceiveTagset.DHInitialize (m_CK, keydata + 32); // tagset_ba = DH_INITIALIZE(chainKey, k_ba)
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m_ReceiveTagset.NextSessionTagRatchet ();
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GenerateMoreReceiveTags (GetOwner ()->GetNumTags ());
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i2p::crypto::HKDF (keydata + 32, nullptr, 0, "AttachPayloadKDF", keydata, 32); // k = HKDF(k_ba, ZEROLEN, "AttachPayloadKDF", 32)
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// decrypt payload
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std::vector<uint8_t> payload (len - 16);
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if (!i2p::crypto::AEADChaCha20Poly1305 (buf, len - 16, m_H, 32, keydata, nonce, payload.data (), len - 16, false)) // decrypt
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{
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LogPrint (eLogWarning, "Garlic: Payload section AEAD decryption failed");
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return false;
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}
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m_State = eSessionStateEstablished;
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GetOwner ()->AddECIESx25519Session (m_RemoteStaticKey, shared_from_this ());
|
|
HandlePayload (payload.data (), len - 16);
|
|
|
|
return true;
|
|
}
|
|
|
|
bool ECIESX25519AEADRatchetSession::NewExistingSessionMessage (const uint8_t * payload, size_t len, uint8_t * out, size_t outLen)
|
|
{
|
|
uint8_t nonce[12];
|
|
auto index = m_SendTagset.GetNextIndex ();
|
|
CreateNonce (index, nonce); // tag's index
|
|
uint64_t tag = m_SendTagset.GetNextSessionTag ();
|
|
memcpy (out, &tag, 8);
|
|
// ad = The session tag, 8 bytes
|
|
// ciphertext = ENCRYPT(k, n, payload, ad)
|
|
uint8_t key[32];
|
|
m_SendTagset.GetSymmKey (index, key);
|
|
if (!i2p::crypto::AEADChaCha20Poly1305 (payload, len, out, 8, key, nonce, out + 8, outLen - 8, true)) // encrypt
|
|
{
|
|
LogPrint (eLogWarning, "Garlic: Payload section AEAD encryption failed");
|
|
return false;
|
|
}
|
|
return true;
|
|
}
|
|
|
|
bool ECIESX25519AEADRatchetSession::HandleExistingSessionMessage (const uint8_t * buf, size_t len, int index)
|
|
{
|
|
uint8_t nonce[12];
|
|
CreateNonce (index, nonce); // tag's index
|
|
len -= 8; // tag
|
|
std::vector<uint8_t> payload (len - 16);
|
|
uint8_t key[32];
|
|
m_ReceiveTagset.GetSymmKey (index, key);
|
|
if (!i2p::crypto::AEADChaCha20Poly1305 (buf + 8, len - 16, buf, 8, key, nonce, payload.data (), len - 16, false)) // decrypt
|
|
{
|
|
LogPrint (eLogWarning, "Garlic: Payload section AEAD decryption failed");
|
|
return false;
|
|
}
|
|
HandlePayload (payload.data (), len - 16, index);
|
|
if (m_ReceiveTagset.GetNextIndex () - index <= GetOwner ()->GetNumTags ()*2/3)
|
|
GenerateMoreReceiveTags (GetOwner ()->GetNumTags ());
|
|
return true;
|
|
}
|
|
|
|
bool ECIESX25519AEADRatchetSession::HandleNextMessage (const uint8_t * buf, size_t len, int index)
|
|
{
|
|
m_LastActivityTimestamp = i2p::util::GetSecondsSinceEpoch ();
|
|
switch (m_State)
|
|
{
|
|
case eSessionStateNewSessionReplySent:
|
|
m_State = eSessionStateEstablished;
|
|
#if (__cplusplus >= 201703L) // C++ 17 or higher
|
|
[[fallthrough]];
|
|
#endif
|
|
case eSessionStateEstablished:
|
|
return HandleExistingSessionMessage (buf, len, index);
|
|
case eSessionStateNew:
|
|
return HandleNewIncomingSession (buf, len);
|
|
case eSessionStateNewSessionSent:
|
|
return HandleNewOutgoingSessionReply (buf, len);
|
|
default:
|
|
return false;
|
|
}
|
|
return true;
|
|
}
|
|
|
|
std::shared_ptr<I2NPMessage> ECIESX25519AEADRatchetSession::WrapSingleMessage (std::shared_ptr<const I2NPMessage> msg)
|
|
{
|
|
auto m = NewI2NPMessage ();
|
|
m->Align (12); // in order to get buf aligned to 16 (12 + 4)
|
|
uint8_t * buf = m->GetPayload () + 4; // 4 bytes for length
|
|
auto payload = CreatePayload (msg);
|
|
size_t len = payload.size ();
|
|
|
|
switch (m_State)
|
|
{
|
|
case eSessionStateEstablished:
|
|
if (!NewExistingSessionMessage (payload.data (), payload.size (), buf, m->maxLen))
|
|
return nullptr;
|
|
len += 24;
|
|
break;
|
|
case eSessionStateNew:
|
|
if (!NewOutgoingSessionMessage (payload.data (), payload.size (), buf, m->maxLen))
|
|
return nullptr;
|
|
len += 96;
|
|
break;
|
|
case eSessionStateNewSessionReceived:
|
|
if (!NewSessionReplyMessage (payload.data (), payload.size (), buf, m->maxLen))
|
|
return nullptr;
|
|
len += 72;
|
|
break;
|
|
case eSessionStateNewSessionReplySent:
|
|
if (!NextNewSessionReplyMessage (payload.data (), payload.size (), buf, m->maxLen))
|
|
return nullptr;
|
|
len += 72;
|
|
break;
|
|
default:
|
|
return nullptr;
|
|
}
|
|
|
|
htobe32buf (m->GetPayload (), len);
|
|
m->len += len + 4;
|
|
m->FillI2NPMessageHeader (eI2NPGarlic);
|
|
return m;
|
|
}
|
|
|
|
std::vector<uint8_t> ECIESX25519AEADRatchetSession::CreatePayload (std::shared_ptr<const I2NPMessage> msg)
|
|
{
|
|
uint64_t ts = i2p::util::GetMillisecondsSinceEpoch ();
|
|
size_t payloadLen = 7; // datatime
|
|
if (msg && m_Destination)
|
|
payloadLen += msg->GetPayloadLength () + 13 + 32;
|
|
auto leaseSet = (GetLeaseSetUpdateStatus () == eLeaseSetUpdated) ? CreateDatabaseStoreMsg (GetOwner ()->GetLeaseSet ()) : nullptr;
|
|
std::shared_ptr<I2NPMessage> deliveryStatus;
|
|
if (leaseSet)
|
|
{
|
|
payloadLen += leaseSet->GetPayloadLength () + 13;
|
|
deliveryStatus = CreateEncryptedDeliveryStatusMsg (leaseSet->GetMsgID ());
|
|
payloadLen += deliveryStatus->GetPayloadLength () + 49;
|
|
if (GetLeaseSetUpdateMsgID ()) GetOwner ()->RemoveDeliveryStatusSession (GetLeaseSetUpdateMsgID ()); // remove previous
|
|
SetLeaseSetUpdateStatus (eLeaseSetSubmitted);
|
|
SetLeaseSetUpdateMsgID (leaseSet->GetMsgID ());
|
|
SetLeaseSetSubmissionTime (ts);
|
|
GetOwner ()->DeliveryStatusSent (shared_from_this (), leaseSet->GetMsgID ());
|
|
}
|
|
if (m_AckRequests.size () > 0)
|
|
payloadLen += m_AckRequests.size ()*4 + 3;
|
|
uint8_t paddingSize;
|
|
RAND_bytes (&paddingSize, 1);
|
|
paddingSize &= 0x0F; paddingSize++; // 1 - 16
|
|
payloadLen += paddingSize + 3;
|
|
std::vector<uint8_t> v(payloadLen);
|
|
size_t offset = 0;
|
|
// DateTime
|
|
v[offset] = eECIESx25519BlkDateTime; offset++;
|
|
htobe16buf (v.data () + offset, 4); offset += 2;
|
|
htobe32buf (v.data () + offset, ts/1000); offset += 4; // in seconds
|
|
// LeaseSet
|
|
if (leaseSet)
|
|
offset += CreateGarlicClove (leaseSet, v.data () + offset, payloadLen - offset);
|
|
// DeliveryStatus
|
|
if (deliveryStatus)
|
|
offset += CreateDeliveryStatusClove (deliveryStatus, v.data () + offset, payloadLen - offset);
|
|
// msg
|
|
if (msg && m_Destination)
|
|
offset += CreateGarlicClove (msg, v.data () + offset, payloadLen - offset, true);
|
|
// ack
|
|
if (m_AckRequests.size () > 0)
|
|
{
|
|
v[offset] = eECIESx25519BlkAck; offset++;
|
|
htobe16buf (v.data () + offset, m_AckRequests.size ()*4); offset += 2;
|
|
for (auto& it: m_AckRequests)
|
|
{
|
|
htobe16buf (v.data () + offset, it.first); offset += 2;
|
|
htobe16buf (v.data () + offset, it.second); offset += 2;
|
|
}
|
|
m_AckRequests.clear ();
|
|
}
|
|
// padding
|
|
v[offset] = eECIESx25519BlkPadding; offset++;
|
|
htobe16buf (v.data () + offset, paddingSize); offset += 2;
|
|
memset (v.data () + offset, 0, paddingSize); offset += paddingSize;
|
|
return v;
|
|
}
|
|
|
|
size_t ECIESX25519AEADRatchetSession::CreateGarlicClove (std::shared_ptr<const I2NPMessage> msg, uint8_t * buf, size_t len, bool isDestination)
|
|
{
|
|
if (!msg) return 0;
|
|
uint16_t cloveSize = msg->GetPayloadLength () + 9 + 1;
|
|
if (isDestination) cloveSize += 32;
|
|
if ((int)len < cloveSize + 3) return 0;
|
|
buf[0] = eECIESx25519BlkGalicClove; // clove type
|
|
htobe16buf (buf + 1, cloveSize); // size
|
|
buf += 3;
|
|
if (isDestination)
|
|
{
|
|
*buf = (eGarlicDeliveryTypeDestination << 5);
|
|
memcpy (buf + 1, *m_Destination, 32); buf += 32;
|
|
}
|
|
else
|
|
*buf = 0;
|
|
buf++; // flag and delivery instructions
|
|
*buf = msg->GetTypeID (); // I2NP msg type
|
|
htobe32buf (buf + 1, msg->GetMsgID ()); // msgID
|
|
htobe32buf (buf + 5, msg->GetExpiration ()/1000); // expiration in seconds
|
|
memcpy (buf + 9, msg->GetPayload (), msg->GetPayloadLength ());
|
|
return cloveSize + 3;
|
|
}
|
|
|
|
size_t ECIESX25519AEADRatchetSession::CreateDeliveryStatusClove (std::shared_ptr<const I2NPMessage> msg, uint8_t * buf, size_t len)
|
|
{
|
|
uint16_t cloveSize = msg->GetPayloadLength () + 9 + 37 /* delivery instruction */;
|
|
if ((int)len < cloveSize + 3) return 0;
|
|
buf[0] = eECIESx25519BlkGalicClove; // clove type
|
|
htobe16buf (buf + 1, cloveSize); // size
|
|
buf += 3;
|
|
if (GetOwner ())
|
|
{
|
|
auto inboundTunnel = GetOwner ()->GetTunnelPool ()->GetNextInboundTunnel ();
|
|
if (inboundTunnel)
|
|
{
|
|
// delivery instructions
|
|
*buf = eGarlicDeliveryTypeTunnel << 5; buf++; // delivery instructions flag tunnel
|
|
// hash and tunnelID sequence is reversed for Garlic
|
|
memcpy (buf, inboundTunnel->GetNextIdentHash (), 32); buf += 32;// To Hash
|
|
htobe32buf (buf, inboundTunnel->GetNextTunnelID ()); buf += 4;// tunnelID
|
|
}
|
|
else
|
|
{
|
|
LogPrint (eLogError, "Garlic: No inbound tunnels in the pool for DeliveryStatus");
|
|
return 0;
|
|
}
|
|
*buf = msg->GetTypeID (); // I2NP msg type
|
|
htobe32buf (buf + 1, msg->GetMsgID ()); // msgID
|
|
htobe32buf (buf + 5, msg->GetExpiration ()/1000); // expiration in seconds
|
|
memcpy (buf + 9, msg->GetPayload (), msg->GetPayloadLength ());
|
|
}
|
|
else
|
|
return 0;
|
|
return cloveSize + 3;
|
|
}
|
|
|
|
void ECIESX25519AEADRatchetSession::GenerateMoreReceiveTags (int numTags)
|
|
{
|
|
for (int i = 0; i < numTags; i++)
|
|
{
|
|
auto index = m_ReceiveTagset.GetNextIndex ();
|
|
uint64_t tag = m_ReceiveTagset.GetNextSessionTag ();
|
|
GetOwner ()->AddECIESx25519SessionTag (index, tag, shared_from_this ());
|
|
}
|
|
}
|
|
|
|
bool ECIESX25519AEADRatchetSession::CheckExpired (uint64_t ts)
|
|
{
|
|
CleanupUnconfirmedLeaseSet (ts);
|
|
return ts > m_LastActivityTimestamp + ECIESX25519_EXPIRATION_TIMEOUT;
|
|
}
|
|
}
|
|
}
|
|
|
|
|