tcp: fix RCV.WND set incorreclty when peer doesn't support WSCALE option

Change-Id: I911fdeeb25bc1112cd38eaa96c34f47a7bf49060
Signed-off-by: Konstantin Ananyev <konstantin.ananyev@intel.com>

2 files changed, 13 insertions, 1 deletions

diff --git a/lib/libtle_l4p/tcp_ctl.h b/lib/libtle_l4p/tcp_ctl.h
index 95c2bbc..8e15b2b 100644
--- a/lib/libtle_l4p/tcp_ctl.h
+++ b/lib/libtle_l4p/tcp_ctl.h
@@ -45,7 +45,14 @@ tcp_stream_up(struct tle_tcp_stream *s)
 static inline uint32_t
 calc_rx_wnd(const struct tle_tcp_stream *s, uint32_t scale)
 {
-	return  s->rx.q->prod.mask << scale;
+	uint32_t wnd;
+
+	/* peer doesn't support WSCALE option, wnd size is limited to 64K */
+	if (scale == TCP_WSCALE_NONE) {
+		wnd = s->rx.q->prod.mask << TCP_WSCALE_DEFAULT;
+		return RTE_MIN(wnd, (uint32_t)UINT16_MAX);
+	} else
+		return  s->rx.q->prod.mask << scale;
 }
 
 /* empty stream's receive queue */
diff --git a/lib/libtle_l4p/tcp_rxtx.c b/lib/libtle_l4p/tcp_rxtx.c
index a6b3989..b525751 100644
--- a/lib/libtle_l4p/tcp_rxtx.c
+++ b/lib/libtle_l4p/tcp_rxtx.c
@@ -1547,6 +1547,11 @@ rx_synack(struct tle_tcp_stream *s, uint32_t ts, uint32_t state,
 	s->tcb.rcv.irs = si->seq;
 	s->tcb.rcv.nxt = si->seq + 1;
 
+	/* if peer doesn't support WSCALE opt, recalculate RCV.WND */
+	s->tcb.rcv.wscale = (so.wscale == TCP_WSCALE_NONE) ?
+		TCP_WSCALE_NONE : TCP_WSCALE_DEFAULT;
+	s->tcb.rcv.wnd = calc_rx_wnd(s, s->tcb.rcv.wscale);
+
 	/* calculate initial rto */
 	rto_estimate(&s->tcb, ts - s->tcb.snd.ts);