The wget test seriously broken:
* Uses zero values for ISS and IRS values (see RFC 9293).
* Writes incorrect values to Sequence and Acknowledgment numbers fields
of tcp packets. In the real life such packets will break the tcp stream.
* The test should fail (see above), but due to buggy old tcp implementation
it passes.
This patch fix all bugs mentioned above, so the test passes with new
and better tcp implementation.
Signed-off-by: Mikhail Kshevetskiy <mikhail.kshevets...@iopsys.eu>
---
arch/sandbox/include/asm/eth.h | 4 +++
test/cmd/wget.c | 45 ++++++++++++++++++++++++----------
2 files changed, 36 insertions(+), 13 deletions(-)
diff --git a/arch/sandbox/include/asm/eth.h b/arch/sandbox/include/asm/eth.h
index f042a5f3b92..083a7371a3f 100644
--- a/arch/sandbox/include/asm/eth.h
+++ b/arch/sandbox/include/asm/eth.h
@@ -77,6 +77,8 @@ typedef int sandbox_eth_tx_hand_f(struct udevice *dev, void
*pkt,
* fake_host_hwaddr - MAC address of mocked machine
* fake_host_ipaddr - IP address of mocked machine
* disabled - Will not respond
+ * irs - tcp initial receive sequence
+ * iss - tcp initial send sequence
* recv_packet_buffer - buffers of the packet returned as received
* recv_packet_length - lengths of the packet returned as received
* recv_packets - number of packets returned
@@ -87,6 +89,8 @@ struct eth_sandbox_priv {
uchar fake_host_hwaddr[ARP_HLEN];
struct in_addr fake_host_ipaddr;
bool disabled;
+ u32 irs;
+ u32 iss;
uchar * recv_packet_buffer[PKTBUFSRX];
int recv_packet_length[PKTBUFSRX];
int recv_packets;
diff --git a/test/cmd/wget.c b/test/cmd/wget.c
index 356a4dcd8fa..3e9a5f354fc 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)
+#define GET_TCP_HDR_LEN_IN_BYTES(x) ((x) >> 2)
+
static int sb_arp_handler(struct udevice *dev, void *packet,
unsigned int len)
{
@@ -62,12 +64,14 @@ static int sb_syn_handler(struct udevice *dev, void *packet,
eth_send = (void *)priv->recv_packet_buffer[priv->recv_packets];
memcpy(eth_send->et_dest, eth->et_src, ARP_HLEN);
memcpy(eth_send->et_src, priv->fake_host_hwaddr, ARP_HLEN);
+ priv->irs = ntohl(tcp->tcp_seq);
+ priv->iss = ~priv->irs; /* just to differ from irs */
eth_send->et_protlen = htons(PROT_IP);
tcp_send = (void *)eth_send + ETHER_HDR_SIZE;
tcp_send->tcp_src = tcp->tcp_dst;
tcp_send->tcp_dst = tcp->tcp_src;
- tcp_send->tcp_seq = htonl(0);
- tcp_send->tcp_ack = htonl(ntohl(tcp->tcp_seq) + 1);
+ tcp_send->tcp_seq = htonl(priv->iss);
+ tcp_send->tcp_ack = htonl(priv->irs + 1);
tcp_send->tcp_hlen =
SHIFT_TO_TCPHDRLEN_FIELD(LEN_B_TO_DW(TCP_HDR_SIZE));
tcp_send->tcp_flags = TCP_SYN | TCP_ACK;
tcp_send->tcp_win = htons(PKTBUFSRX * TCP_MSS >> TCP_SCALE);
@@ -102,6 +106,8 @@ static int sb_ack_handler(struct udevice *dev, void *packet,
void *data;
int pkt_len;
int payload_len = 0;
+ u32 tcp_seq, tcp_ack;
+ int tcp_data_len;
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";
@@ -119,17 +125,32 @@ 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) {
- tcp_send->tcp_seq = htonl(ntohl(tcp->tcp_ack));
- tcp_send->tcp_ack = htonl(ntohl(tcp->tcp_seq) + 1);
+ tcp_seq = ntohl(tcp->tcp_seq) - priv->irs;
+ tcp_ack = ntohl(tcp->tcp_ack) - priv->iss;
+ tcp_data_len = len - ETHER_HDR_SIZE - IP_HDR_SIZE -
GET_TCP_HDR_LEN_IN_BYTES(tcp->tcp_hlen);
+
+ if (tcp->tcp_flags & TCP_FIN)
+ tcp_data_len++;
+
+ tcp_send->tcp_seq = htonl(ntohl(tcp->tcp_ack));
+ tcp_send->tcp_ack = htonl(ntohl(tcp->tcp_seq) + tcp_data_len);
+
+ if (tcp_seq == 1 && tcp_ack == 1) {
+ if (tcp_data_len == 0) {
+ /* no data, wait for GET request */
+ return -1;
+ }
+
+ /* reply to GET request */
payload_len = strlen(payload1);
memcpy(data, payload1, payload_len);
tcp_send->tcp_flags = TCP_ACK;
- } else if (ntohl(tcp->tcp_seq) == 2) {
- tcp_send->tcp_seq = htonl(ntohl(tcp->tcp_ack));
- tcp_send->tcp_ack = htonl(ntohl(tcp->tcp_seq) + 1);
+ } else if (tcp_ack == 1 + strlen(payload1)) {
payload_len = 0;
tcp_send->tcp_flags = TCP_ACK | TCP_FIN;
+ } else if (tcp_ack == 2 + strlen(payload1)) {
+ payload_len = 0;
+ tcp_send->tcp_flags = TCP_ACK;
}
tcp_send->tcp_hlen =
SHIFT_TO_TCPHDRLEN_FIELD(LEN_B_TO_DW(TCP_HDR_SIZE));
@@ -148,11 +169,9 @@ 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;
}
--
2.45.2
