handle Retry message

This commit is contained in:
orignal 2022-03-20 15:10:18 -04:00
parent 324932c758
commit 30e6984889
2 changed files with 32 additions and 8 deletions

View File

@ -53,7 +53,7 @@ namespace transport
SendSessionRequest ();
}
void SSU2Session::SendSessionRequest ()
void SSU2Session::SendSessionRequest (uint64_t token)
{
// we are Alice
m_EphemeralKeys = i2p::transport::transports.GetNextX25519KeysPair ();
@ -70,7 +70,7 @@ namespace transport
header.h.flags[2] = 0; // flag
RAND_bytes ((uint8_t *)&m_SourceConnID, 8);
memcpy (headerX, &m_SourceConnID, 8); // source id
RAND_bytes (headerX + 8, 8); // token
memcpy (headerX + 8, &token, 8); // token
memcpy (headerX + 16, m_EphemeralKeys->GetPublicKey (), 32); // X
// payload
payload[0] = eSSU2BlkDateTime;
@ -193,8 +193,8 @@ namespace transport
{
// we are Alice
Header header;
header.h.connID = m_SourceConnID;
memcpy (header.buf + 8, buf + 8, 8);
memcpy (header.buf, buf, 16);
header.ll[0] ^= CreateHeaderMask (m_Address->i, buf + (len - 24));
uint8_t kh2[32];
i2p::crypto::HKDF (m_NoiseState->m_CK, nullptr, 0, "SessCreateHeader", kh2, 32); // k_header_2 = HKDF(chainKey, ZEROLEN, "SessCreateHeader", 32)
header.ll[1] ^= CreateHeaderMask (kh2, buf + (len - 12));
@ -227,6 +227,27 @@ namespace transport
return true;
}
bool SSU2Session::ProcessRetry (uint8_t * buf, size_t len)
{
// we are Alice
Header header;
memcpy (header.buf, buf, 16);
header.ll[0] ^= CreateHeaderMask (m_Address->i, buf + (len - 24));
header.ll[1] ^= CreateHeaderMask (m_Address->i, buf + (len - 12));
if (header.h.type != eSSU2Retry)
{
LogPrint (eLogWarning, "SSU2: Unexpected message type ", (int)header.h.type);
return false;
}
const uint8_t nonce[12] = {0};
uint64_t headerX[2]; // sourceConnID, token
i2p::crypto::ChaCha20 (buf + 16, 16, m_Address->i, nonce, (uint8_t *)headerX);
// TODO: decrypt and handle payload
InitNoiseXKState1 (*m_NoiseState, m_Address->s); // reset Noise
SendSessionRequest (headerX[1]);
return true;
}
void SSU2Session::HandlePayload (const uint8_t * buf, size_t len)
{
size_t offset = 0;
@ -477,11 +498,12 @@ namespace transport
}
else
{
// check pending sessions if it's SessionCreated
// check pending sessions if it's SessionCreated or Retry
auto it1 = m_PendingOutgoingSessions.find (senderEndpoint);
if (it1 != m_PendingOutgoingSessions.end ())
{
if (it1->second->ProcessSessionCreated (buf, len))
if (it1->second->ProcessSessionCreated (buf, len) ||
it1->second->ProcessRetry (buf, len))
m_PendingOutgoingSessions.erase (it1);
}
else

View File

@ -31,7 +31,8 @@ namespace transport
enum SSU2MessageType
{
eSSU2SessionRequest = 0,
eSSU2SessionCreated = 1
eSSU2SessionCreated = 1,
eSSU2Retry = 9
};
enum SSU2BlockType
@ -90,10 +91,11 @@ namespace transport
void ProcessSessionRequest (uint64_t connID, uint8_t * buf, size_t len);
bool ProcessSessionCreated (uint8_t * buf, size_t len);
bool ProcessRetry (uint8_t * buf, size_t len);
private:
void SendSessionRequest ();
void SendSessionRequest (uint64_t token = 0);
void SendSessionCreated (const uint8_t * X);
void HandlePayload (const uint8_t * buf, size_t len);