From a510e7c2c653dacd3ed753ba126db3319163e1d9 Mon Sep 17 00:00:00 2001
From: orignal <romakoshelkin@yandex.ru>
Date: Sat, 12 Apr 2014 21:13:30 -0400
Subject: [PATCH] check for duplicate and missing fragments
---
SSU.cpp | 36 ++++++++++++++++++++++++++++++------
SSU.h | 10 +++++++++-
2 files changed, 39 insertions(+), 7 deletions(-)
diff --git a/SSU.cpp b/SSU.cpp
index d033ec36..69b105f8 100644
--- a/SSU.cpp
+++ b/SSU.cpp
@@ -27,6 +27,12 @@ namespace ssu
SSUSession::~SSUSession ()
{
delete m_DHKeysPair;
+ for (auto it: m_IncomleteMessages)
+ if (it.second)
+ {
+ DeleteI2NPMessage (it.second->msg);
+ delete it.second;
+ }
}
void SSUSession::CreateAESandMacKey (uint8_t * pubKey, uint8_t * aesKey, uint8_t * macKey)
@@ -673,9 +679,29 @@ namespace ssu
auto it = m_IncomleteMessages.find (msgID);
if (it != m_IncomleteMessages.end ())
{
- msg = it->second;
- memcpy (msg->buf + msg->len, buf, fragmentSize);
- msg->len += fragmentSize;
+ if (fragmentNum == it->second->nextFragmentNum)
+ {
+ // expected fragment
+ msg = it->second->msg;
+ memcpy (msg->buf + msg->len, buf, fragmentSize);
+ msg->len += fragmentSize;
+ it->second->nextFragmentNum++;
+ }
+ else if (fragmentNum < it->second->nextFragmentNum)
+ // duplicate fragment
+ LogPrint ("Duplicate fragment ", fragmentNum, " of message ", msgID, ". Ignored");
+ else
+ {
+ // missing fragment
+ LogPrint ("Missing fragments from ", it->second->nextFragmentNum, " to ", fragmentNum - 1, " of message ", msgID);
+ //TODO
+ }
+
+ if (isLast)
+ {
+ delete it->second;
+ m_IncomleteMessages.erase (it);
+ }
}
else
// TODO:
@@ -691,12 +717,10 @@ namespace ssu
if (msg)
{
if (!fragmentNum && !isLast)
- m_IncomleteMessages[msgID] = msg;
+ m_IncomleteMessages[msgID] = new IncompleteMessage (msg);
if (isLast)
{
SendMsgAck (msgID);
- if (fragmentNum > 0)
- m_IncomleteMessages.erase (msgID);
msg->FromSSU (msgID);
if (m_State == eSessionStateEstablished)
i2p::HandleI2NPMessage (msg);
diff --git a/SSU.h b/SSU.h
index 3f7ac96b..8ad3fecf 100644
--- a/SSU.h
+++ b/SSU.h
@@ -124,6 +124,14 @@ namespace ssu
void HandleTerminationTimer (const boost::system::error_code& ecode);
private:
+
+ struct IncompleteMessage
+ {
+ I2NPMessage * msg;
+ uint8_t nextFragmentNum;
+
+ IncompleteMessage (I2NPMessage * m): msg (m), nextFragmentNum (1) {};
+ };
SSUServer& m_Server;
boost::asio::ip::udp::endpoint m_RemoteEndpoint;
@@ -137,7 +145,7 @@ namespace ssu
CryptoPP::CBC_Mode<CryptoPP::AES>::Encryption m_Encryption;
CryptoPP::CBC_Mode<CryptoPP::AES>::Decryption m_Decryption;
uint8_t m_SessionKey[32], m_MacKey[32];
- std::map<uint32_t, I2NPMessage *> m_IncomleteMessages;
+ std::map<uint32_t, IncompleteMessage *> m_IncomleteMessages;
std::list<i2p::I2NPMessage *> m_DelayedMessages;
};