[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[Qemu-devel] [PATCH v3 2/2] filter-rewriter: skip net_checksum_calculate
From: |
zhanghailiang |
Subject: |
[Qemu-devel] [PATCH v3 2/2] filter-rewriter: skip net_checksum_calculate() while offset = 0 |
Date: |
Tue, 28 Feb 2017 11:54:19 +0800 |
While the offset of packets's sequence for primary side and
secondary side is zero, it is unnecessary to call net_checksum_calculate()
to recalculate the checksume value of packets.
Signed-off-by: zhanghailiang <address@hidden>
---
net/filter-rewriter.c | 17 +++++++++++------
1 file changed, 11 insertions(+), 6 deletions(-)
diff --git a/net/filter-rewriter.c b/net/filter-rewriter.c
index c4ab91c..afa06e8 100644
--- a/net/filter-rewriter.c
+++ b/net/filter-rewriter.c
@@ -93,10 +93,12 @@ static int handle_primary_tcp_pkt(NetFilterState *nf,
conn->offset -= (ntohl(tcp_pkt->th_ack) - 1);
conn->syn_flag = 0;
}
- /* handle packets to the secondary from the primary */
- tcp_pkt->th_ack = htonl(ntohl(tcp_pkt->th_ack) + conn->offset);
+ if (conn->offset) {
+ /* handle packets to the secondary from the primary */
+ tcp_pkt->th_ack = htonl(ntohl(tcp_pkt->th_ack) + conn->offset);
- net_checksum_calculate((uint8_t *)pkt->data, pkt->size);
+ net_checksum_calculate((uint8_t *)pkt->data, pkt->size);
+ }
}
return 0;
@@ -129,10 +131,13 @@ static int handle_secondary_tcp_pkt(NetFilterState *nf,
}
if ((tcp_pkt->th_flags & (TH_ACK | TH_SYN)) == TH_ACK) {
- /* handle packets to the primary from the secondary*/
- tcp_pkt->th_seq = htonl(ntohl(tcp_pkt->th_seq) - conn->offset);
+ /* Only need to adjust seq while offset is Non-zero */
+ if (conn->offset) {
+ /* handle packets to the primary from the secondary*/
+ tcp_pkt->th_seq = htonl(ntohl(tcp_pkt->th_seq) - conn->offset);
- net_checksum_calculate((uint8_t *)pkt->data, pkt->size);
+ net_checksum_calculate((uint8_t *)pkt->data, pkt->size);
+ }
}
return 0;
--
1.8.3.1