diff --git a/libi2pd/Garlic.cpp b/libi2pd/Garlic.cpp index 371aabff..3c255d0d 100644 --- a/libi2pd/Garlic.cpp +++ b/libi2pd/Garlic.cpp @@ -832,7 +832,7 @@ namespace garlic void GarlicDestination::HandleECIESx25519 (const uint8_t * buf, size_t len) { - // KDF + // KDF1 // TODO : use precalculated hashes static const char protocolName[41] = "Noise_IKelg2+hs2_25519_ChaChaPoly_SHA256"; // 40 bytes uint8_t h[64], ck[32]; @@ -849,7 +849,7 @@ namespace garlic LogPrint (eLogError, "Garlic: Can't decode elligator"); return; } - buf += 32; + buf += 32; len -= 32; memcpy (h + 32, aepk, 32); SHA256 (h, 64, h); // h = SHA256(h || aepk) @@ -866,7 +866,69 @@ namespace garlic LogPrint (eLogWarning, "Garlic: Flags/static section AEAD verification failed "); return; } - buf += 48; // 32 data + 16 poly + memcpy (h + 32, buf, 32); + SHA256 (h, 64, h); // h = SHA256(h || ciphertext) + buf += 48; len -= 48; // 32 data + 16 poly + // decrypt payload + std::vector payload (len + 32); uint8_t h1[32]; + // KDF2 for payload + bool isStatic = !i2p::data::Tag<32> (fs).IsZero (); + if (isStatic) + { + // static key, fs is apk + Decrypt (fs, sharedSecret, m_Ctx); // DH(bsk, apk) + i2p::crypto::HKDF (ck, sharedSecret, 32, "", keyData); // keydata = HKDF(chainKey, sharedSecret, "", 64) + memcpy (ck, keyData, 32); // chainKey = keydata[0:31] + memcpy (payload.data (), h, 32); + memcpy (payload.data () + 32, buf, len); // h || ciphertext + SHA256 (payload.data (), len + 32, h1); + } + else // all zeros flags + htole64buf (nonce + 4, 1); // n = 1 + if (!i2p::crypto::AEADChaCha20Poly1305 (buf, len - 16, h, 32, keyData + 32, nonce, payload.data () + 32, len - 16, false)) // decrypt + { + LogPrint (eLogWarning, "Garlic: Payload section AEAD verification failed"); + return; + } + if (isStatic) memcpy (h, h1, 32); // h = SHA256(h || ciphertext) + HandleECIESx25519Payload (payload.data () + 32, len - 16); } + + void GarlicDestination::HandleECIESx25519Payload (const uint8_t * buf, size_t len) + { + size_t offset = 0; + while (offset < len) + { + uint8_t blk = buf[offset]; + offset++; + auto size = bufbe16toh (buf + offset); + offset += 2; + LogPrint (eLogDebug, "Garlic: Block type ", (int)blk, " of size ", size); + if (size > len) + { + LogPrint (eLogError, "Garlic: Unexpected block length ", size); + break; + } + switch (blk) + { + case eECIESx25519BlkGalicClove: + // TODO: + break; + case eECIESx25519BlkDateTime: + LogPrint (eLogDebug, "Garlic: datetime"); + break; + case eECIESx25519BlkOptions: + LogPrint (eLogDebug, "Garlic: options"); + break; + case eECIESx25519BlkPadding: + LogPrint (eLogDebug, "NTCP2: padding"); + break; + default: + LogPrint (eLogWarning, "Garlic: Unknown block type ", (int)blk); + } + offset += size; + } + } + } } diff --git a/libi2pd/Garlic.h b/libi2pd/Garlic.h index b34fc00f..4054d88c 100644 --- a/libi2pd/Garlic.h +++ b/libi2pd/Garlic.h @@ -165,6 +165,17 @@ namespace garlic //using GarlicRoutingSessionPtr = std::shared_ptr; typedef std::shared_ptr GarlicRoutingSessionPtr; // TODO: replace to using after switch to 4.8 + enum ECIESx25519BlockType + { + eECIESx25519BlkDateTime = 0, + eECIESx25519BlkSessionID = 1, + eECIESx25519BlkTermination = 4, + eECIESx25519BlkOptions = 5, + eECIESx25519BlkNextSessionKey = 7, + eECIESx25519BlkGalicClove = 11, + eECIESx25519BlkPadding = 254 + }; + class GarlicDestination: public i2p::data::LocalDestination { public: @@ -208,6 +219,7 @@ namespace garlic // ECIES-X25519-AEAD-Ratchet void HandleECIESx25519 (const uint8_t * buf, size_t len); + void HandleECIESx25519Payload (const uint8_t * buf, size_t len); private: