After applying the following patch, wget test on sandbox failed[1].
Commit: cab7867cff ("net: wget: Support retransmission a dropped packet")
Here are two reasons why the test is failed and how to fix it:
1. tcp_ack is calculated by the wrong value.
tcp_ack needs to be calculated by the received TCP payload size.
2. wget command may have a problem that HTTP response from server
must be divided into more than two packets.
In this commit, HTTP response is divided into two packets.
In addition, I fixed the HTTP response returned at the correct timing.
[1]
https://lore.kernel.org/u-boot/caflszthebk2jr8oz6hj21wpsnjjgjhade037rqwhvwt1kjb...@mail.gmail.com/
Signed-off-by: Yasuharu Shibata <[email protected]>
Reported-by: Simon Glass <[email protected]>
---
test/cmd/wget.c | 40 +++++++++++++++++++++++++++++++---------
1 file changed, 31 insertions(+), 9 deletions(-)
diff --git a/test/cmd/wget.c b/test/cmd/wget.c
index 356a4dcd8f..11a07c08f4 100644
--- a/test/cmd/wget.c
+++ b/test/cmd/wget.c
@@ -26,6 +26,8 @@
#define SHIFT_TO_TCPHDRLEN_FIELD(x) ((x) << 4)
#define LEN_B_TO_DW(x) ((x) >> 2)
+int net_set_ack_options(union tcp_build_pkt *b);
+
static int sb_arp_handler(struct udevice *dev, void *packet,
unsigned int len)
{
@@ -105,6 +107,10 @@ static int sb_ack_handler(struct udevice *dev, void
*packet,
const char *payload1 = "HTTP/1.1 200 OK\r\n"
"Content-Length: 30\r\n\r\n\r\n"
"<html><body>Hi</body></html>\r\n";
+ union tcp_build_pkt *b = (union tcp_build_pkt *)tcp;
+ const int recv_payload_len = len - net_set_ack_options(b) - IP_HDR_SIZE
- ETHER_HDR_SIZE;
+ static int next_seq;
+ const int bottom_payload_len = 10;
/* Don't allow the buffer to overrun */
if (priv->recv_packets >= PKTBUFSRX)
@@ -119,13 +125,31 @@ static int sb_ack_handler(struct udevice *dev, void
*packet,
tcp_send->tcp_dst = tcp->tcp_src;
data = (void *)tcp_send + IP_TCP_HDR_SIZE;
- if (ntohl(tcp->tcp_seq) == 1 && ntohl(tcp->tcp_ack) == 1) {
+ if (ntohl(tcp->tcp_seq) == 1 && ntohl(tcp->tcp_ack) == 1 &&
recv_payload_len == 0) {
+ // ignore ACK for three-way handshaking
+ return 0;
+ } else if (ntohl(tcp->tcp_seq) == 1 && ntohl(tcp->tcp_ack) == 1) {
+ // recv HTTP request message and reply top half data
tcp_send->tcp_seq = htonl(ntohl(tcp->tcp_ack));
- tcp_send->tcp_ack = htonl(ntohl(tcp->tcp_seq) + 1);
- payload_len = strlen(payload1);
+ tcp_send->tcp_ack = htonl(ntohl(tcp->tcp_seq) +
recv_payload_len);
+
+ payload_len = strlen(payload1) - bottom_payload_len;
memcpy(data, payload1, payload_len);
tcp_send->tcp_flags = TCP_ACK;
- } else if (ntohl(tcp->tcp_seq) == 2) {
+
+ next_seq = ntohl(tcp_send->tcp_seq) + payload_len;
+ } else if (ntohl(tcp->tcp_ack) == next_seq) {
+ // reply bottom half data
+ const int top_payload_len = strlen(payload1) -
bottom_payload_len;
+
+ tcp_send->tcp_seq = htonl(next_seq);
+ tcp_send->tcp_ack = htonl(ntohl(tcp->tcp_seq) +
recv_payload_len);
+
+ payload_len = bottom_payload_len;
+ memcpy(data, payload1 + top_payload_len, payload_len);
+ tcp_send->tcp_flags = TCP_ACK;
+ } else {
+ // close connection
tcp_send->tcp_seq = htonl(ntohl(tcp->tcp_ack));
tcp_send->tcp_ack = htonl(ntohl(tcp->tcp_seq) + 1);
payload_len = 0;
@@ -148,11 +172,9 @@ static int sb_ack_handler(struct udevice *dev, void
*packet,
pkt_len,
IPPROTO_TCP);
- if (ntohl(tcp->tcp_seq) == 1 || ntohl(tcp->tcp_seq) == 2) {
- priv->recv_packet_length[priv->recv_packets] =
- ETHER_HDR_SIZE + IP_TCP_HDR_SIZE + payload_len;
- ++priv->recv_packets;
- }
+ priv->recv_packet_length[priv->recv_packets] =
+ ETHER_HDR_SIZE + IP_TCP_HDR_SIZE + payload_len;
+ ++priv->recv_packets;
return 0;
}
--
2.20.1
