From b39f302a635e1fc8c1bf2aa1030628e99fb0eed5 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Wiesner=20Andr=C3=A1s?= <wabe@t-email.hu>
Date: Thu, 9 Nov 2023 07:47:50 +0100
Subject: [PATCH] - TCP state cleanup added

---
 prefab/conn_blocks/tcp_connblock.c | 20 ++++++++++++++++++--
 1 file changed, 18 insertions(+), 2 deletions(-)

diff --git a/prefab/conn_blocks/tcp_connblock.c b/prefab/conn_blocks/tcp_connblock.c
index b8d5817..bf6158f 100644
--- a/prefab/conn_blocks/tcp_connblock.c
+++ b/prefab/conn_blocks/tcp_connblock.c
@@ -48,6 +48,22 @@ static bool filtTcp(const PcktSieveFilterCondition *filtCond, const PcktProps *c
     return ipProps->Protocol == ETH_TCP_PACKET_CLASS && references_us;
 }
 
+static inline TcpState * tcps_create() {
+    TcpState * tcps = dynmem_alloc(sizeof(TcpState));
+    tcps->txWin = tcpw_create(ETHLIB_DEF_TCP_WINDOW_SIZE);
+
+    return tcps;
+}
+
+static inline void tcps_remove_and_cleanup(const TcpState * tcps) {
+    if (tcps == NULL) {
+        return;
+    }
+
+    dynmem_free(tcps->txWin);
+    dynmem_free(tcps);
+}
+
 #define TCP_DEFAULT_MSS (1200)
 #define TCP_DEFAULT_RETRY_LIMIT (5)
 #define TCP_DEFAULT_RETRY_TO_HS (100)
@@ -64,7 +80,6 @@ void tcps_init(TcpState *tcps, uint16_t localPort) {
     tcps->rxAckNum = 0;
 
     tcps->localWindow = ETHLIB_DEF_TCP_WINDOW_SIZE;
-    tcps->txWin = tcpw_create(ETHLIB_DEF_TCP_WINDOW_SIZE);
     tcpw_set_seqnum_offset(tcps->txWin, tcps->txSeqNum);
 
     tcps->retryLimit = TCP_DEFAULT_RETRY_LIMIT;
@@ -263,6 +278,7 @@ int tcp_receive_segment_cb(const Pckt *pckt, PcktSieveLayerTag tag) {
     // release descriptor if not meaningful anymore
     if (ret == SIEVE_LAYER_REMOVE_THIS) {
         cbdt_release(E.cbdt, tcps->d); // release descriptor
+        tcps_remove_and_cleanup(tcps); // release TCP state
     }
 
     return ret;
@@ -330,7 +346,7 @@ static inline cbd tcp_new_connblock_filtcond(EthInterface *intf, ip4_addr ipAddr
     ConnBlock ipConnB = ipv4_new_connblock(intf, ipAddr, NULL); // create new IPv4 connection block
 
     PcktSieveLayerTag tag; // store TCP state into sieve layer's tag
-    TcpState *tcpState = dynmem_alloc(sizeof(TcpState));
+    TcpState *tcpState = tcps_create();
     tcps_init(tcpState, port);
     tcpState->userCb = cbFn;
     tag.p = tcpState;