END_TEST
/** Send data with sequence numbers that wrap around the u32_t range.
* Then, provoke RTO retransmission and check that all
* segment lists are still properly sorted. */
START_TEST(test_tcp_rto_rexmit_wraparound)
{
struct netif netif;
struct test_tcp_txcounters txcounters;
struct test_tcp_counters counters;
struct tcp_pcb* pcb;
ip_addr_t remote_ip, local_ip, netmask;
u16_t remote_port = 0x100, local_port = 0x101;
err_t err;
#define SEQNO1 (0xFFFFFF00 - TCP_MSS)
#define ISS 6510
u16_t i, sent_total = 0;
u32_t seqnos[] = {
SEQNO1,
SEQNO1 + (1 * TCP_MSS),
SEQNO1 + (2 * TCP_MSS),
SEQNO1 + (3 * TCP_MSS),
SEQNO1 + (4 * TCP_MSS),
SEQNO1 + (5 * TCP_MSS)};
LWIP_UNUSED_ARG(_i);
for (i = 0; i < sizeof(tx_data); i++) {
tx_data[i] = (u8_t)i;
}
/* initialize local vars */
IP_ADDR4(&local_ip, 192, 168, 1, 1);
IP_ADDR4(&remote_ip, 192, 168, 1, 2);
IP_ADDR4(&netmask, 255, 255, 255, 0);
test_tcp_init_netif(&netif, &txcounters, &local_ip, &netmask);
memset(&counters, 0, sizeof(counters));
/* create and initialize the pcb */
tcp_ticks = 0;
tcp_ticks = 0 - tcp_next_iss();
tcp_ticks = SEQNO1 - tcp_next_iss();
pcb = test_tcp_new_counters_pcb(&counters);
EXPECT_RET(pcb != NULL);
EXPECT(pcb->lastack == SEQNO1);
tcp_set_state(pcb, ESTABLISHED, &local_ip, &remote_ip, local_port, remote_port);
pcb->mss = TCP_MSS;
/* disable initial congestion window (we don't send a SYN here...) */
pcb->cwnd = 2*TCP_MSS;
/* send 6 mss-sized segments */
for (i = 0; i < 6; i++) {
err = tcp_write(pcb, &tx_data[sent_total], TCP_MSS, TCP_WRITE_FLAG_COPY);
EXPECT_RET(err == ERR_OK);
sent_total += TCP_MSS;
}
check_seqnos(pcb->unsent, 6, seqnos);
EXPECT(pcb->unacked == NULL);
err = tcp_output(pcb);
EXPECT(txcounters.num_tx_calls == 2);
EXPECT(txcounters.num_tx_bytes == 2 * (TCP_MSS + 40U));
memset(&txcounters, 0, sizeof(txcounters));
check_seqnos(pcb->unacked, 2, seqnos);
check_seqnos(pcb->unsent, 4, &seqnos[2]);
/* call the tcp timer some times */
for (i = 0; i < 10; i++) {
test_tcp_tmr();
EXPECT(txcounters.num_tx_calls == 0);
}
/* 11th call to tcp_tmr: RTO rexmit fires */
test_tcp_tmr();
EXPECT(txcounters.num_tx_calls == 1);
check_seqnos(pcb->unacked, 1, seqnos);
check_seqnos(pcb->unsent, 5, &seqnos[1]);
/* fake greater cwnd */
pcb->cwnd = pcb->snd_wnd;
/* send more data */
err = tcp_output(pcb);
EXPECT(err == ERR_OK);
/* check queues are sorted */
EXPECT(pcb->unsent == NULL);
check_seqnos(pcb->unacked, 6, seqnos);
/* make sure the pcb is freed */
EXPECT_RET(lwip_stats.memp[MEMP_TCP_PCB].used == 1);
tcp_abort(pcb);
EXPECT_RET(lwip_stats.memp[MEMP_TCP_PCB].used == 0);
}
END_TEST
START_TEST(test_tcp_rto_tracking)
{
struct netif netif;
struct test_tcp_txcounters txcounters;
struct test_tcp_counters counters;
struct tcp_pcb* pcb;
struct pbuf* p;
err_t err;
size_t i;
u16_t sent_total = 0;
LWIP_UNUSED_ARG(_i);
for (i = 0; i < sizeof(tx_data); i++) {
tx_data[i] = (u8_t)i;
}
/* initialize local vars */
test_tcp_init_netif(&netif, &txcounters, &test_local_ip, &test_netmask);
memset(&counters, 0, sizeof(counters));
/* create and initialize the pcb */
tcp_ticks = SEQNO1 - ISS;
pcb = test_tcp_new_counters_pcb(&counters);
EXPECT_RET(pcb != NULL);
tcp_set_state(pcb, ESTABLISHED, &test_local_ip, &test_remote_ip, TEST_LOCAL_PORT, TEST_REMOTE_PORT);
pcb->mss = TCP_MSS;
/* Set congestion window large enough to send all our segments */
pcb->cwnd = 5*TCP_MSS;
/* send 5 mss-sized segments */
for (i = 0; i < 5; i++) {
err = tcp_write(pcb, &tx_data[sent_total], TCP_MSS, TCP_WRITE_FLAG_COPY);
EXPECT_RET(err == ERR_OK);
sent_total += TCP_MSS;
}
check_seqnos(pcb->unsent, 5, seqnos);
EXPECT(pcb->unacked == NULL);
err = tcp_output(pcb);
EXPECT(txcounters.num_tx_calls == 5);
EXPECT(txcounters.num_tx_bytes == 5 * (TCP_MSS + 40U));
memset(&txcounters, 0, sizeof(txcounters));
/* Check all 5 are in-flight */
EXPECT(pcb->unsent == NULL);
check_seqnos(pcb->unacked, 5, seqnos);
/* Force us into retransmisson timeout */
while (!(pcb->flags & TF_RTO)) {
test_tcp_tmr();
}
/* Ensure 4 remaining segments are back on unsent, ready for retransmission */
check_seqnos(pcb->unsent, 4, &seqnos[1]);
/* Ensure 1st segment is on unacked (already retransmitted) */
check_seqnos(pcb->unacked, 1, seqnos);
EXPECT(txcounters.num_tx_calls == 1);
EXPECT(txcounters.num_tx_bytes == TCP_MSS + 40U);
memset(&txcounters, 0, sizeof(txcounters));
/* Ensure rto_end points to next byte */
EXPECT(pcb->rto_end == seqnos[5]);
EXPECT(pcb->rto_end == pcb->snd_nxt);
/* Check cwnd was reset */
EXPECT(pcb->cwnd == pcb->mss);
/* Add another segment to send buffer which is outside of RTO */
err = tcp_write(pcb, &tx_data[sent_total], TCP_MSS, TCP_WRITE_FLAG_COPY);
EXPECT_RET(err == ERR_OK);
sent_total += TCP_MSS;
check_seqnos(pcb->unsent, 5, &seqnos[1]);
/* Ensure no new data was sent */
EXPECT(txcounters.num_tx_calls == 0);
EXPECT(txcounters.num_tx_bytes == 0);
EXPECT(pcb->rto_end == pcb->snd_nxt);
/* ACK first segment */
p = tcp_create_rx_segment(pcb, NULL, 0, 0, TCP_MSS, TCP_ACK);
test_tcp_input(p, &netif);
/* Next two retranmissions should go out, due to cwnd in slow start */
EXPECT(txcounters.num_tx_calls == 2);
EXPECT(txcounters.num_tx_bytes == 2 * (TCP_MSS + 40U));
memset(&txcounters, 0, sizeof(txcounters));
check_seqnos(pcb->unacked, 2, &seqnos[1]);
check_seqnos(pcb->unsent, 3, &seqnos[3]);
/* RTO should still be marked */
EXPECT(pcb->flags & TF_RTO);
/* cwnd should have only grown by 1 MSS */
EXPECT(pcb->cwnd == (tcpwnd_size_t)(2 * pcb->mss));
/* Ensure no new data was sent */
EXPECT(pcb->rto_end == pcb->snd_nxt);
/* ACK the next two segments */
p = tcp_create_rx_segment(pcb, NULL, 0, 0, 2*TCP_MSS, TCP_ACK);
test_tcp_input(p, &netif);
/* Final 2 retransmissions and 1 new data should go out */
EXPECT(txcounters.num_tx_calls == 3);
EXPECT(txcounters.num_tx_bytes == 3 * (TCP_MSS + 40U));
memset(&txcounters, 0, sizeof(txcounters));
check_seqnos(pcb->unacked, 3, &seqnos[3]);
EXPECT(pcb->unsent == NULL);
/* RTO should still be marked */
EXPECT(pcb->flags & TF_RTO);
/* cwnd should have only grown by 1 MSS */
EXPECT(pcb->cwnd == (tcpwnd_size_t)(3 * pcb->mss));
/* snd_nxt should have been advanced past rto_end */
EXPECT(TCP_SEQ_GT(pcb->snd_nxt, pcb->rto_end));
/* ACK the next two segments, finishing our RTO, leaving new segment unacked */
p = tcp_create_rx_segment(pcb, NULL, 0, 0, 2*TCP_MSS, TCP_ACK);
test_tcp_input(p, &netif);
EXPECT(!(pcb->flags & TF_RTO));
check_seqnos(pcb->unacked, 1, &seqnos[5]);
/* We should be in ABC congestion avoidance, so no change in cwnd */
EXPECT(pcb->cwnd == (tcpwnd_size_t)(3 * pcb->mss));
EXPECT(pcb->cwnd >= pcb->ssthresh);
/* Ensure ABC congestion avoidance is tracking bytes acked */
EXPECT(pcb->bytes_acked == (tcpwnd_size_t)(2 * pcb->mss));
/* make sure the pcb is freed */
EXPECT_RET(MEMP_STATS_GET(used, MEMP_TCP_PCB) == 1);
tcp_abort(pcb);
EXPECT_RET(MEMP_STATS_GET(used, MEMP_TCP_PCB) == 0);
}
END_TEST
START_TEST(test_tcp_persist_split)
{
struct netif netif;
struct test_tcp_txcounters txcounters;
struct test_tcp_counters counters;
struct tcp_pcb *pcb;
struct pbuf* p;
err_t err;
size_t i;
LWIP_UNUSED_ARG(_i);
/* Setup data for four segments */
for (i = 0; i < 4 * TCP_MSS; i++) {
tx_data[i] = (u8_t)i;
}
/* initialize local vars */
test_tcp_init_netif(&netif, &txcounters, &test_local_ip, &test_netmask);
memset(&counters, 0, sizeof(counters));
/* create and initialize the pcb */
tcp_ticks = SEQNO1 - ISS;
pcb = test_tcp_new_counters_pcb(&counters);
EXPECT_RET(pcb != NULL);
tcp_set_state(pcb, ESTABLISHED, &test_local_ip, &test_remote_ip, TEST_LOCAL_PORT, TEST_REMOTE_PORT);
pcb->mss = TCP_MSS;
/* set window to three segments */
pcb->cwnd = 3 * TCP_MSS;
pcb->snd_wnd = 3 * TCP_MSS;
pcb->snd_wnd_max = 3 * TCP_MSS;
/* send three segments */
err = tcp_write(pcb, &tx_data[0], 3 * TCP_MSS, TCP_WRITE_FLAG_COPY);
EXPECT(err == ERR_OK);
err = tcp_output(pcb);
EXPECT(err == ERR_OK);
/* verify segments are in-flight */
EXPECT(pcb->unsent == NULL);
EXPECT(pcb->unacked != NULL);
check_seqnos(pcb->unacked, 3, seqnos);
EXPECT(txcounters.num_tx_calls == 3);
EXPECT(txcounters.num_tx_bytes == 3 * (TCP_MSS + 40U));
memset(&txcounters, 0, sizeof(txcounters));
/* ACK the segments and update the window to only 1/2 TCP_MSS */
p = tcp_create_rx_segment_wnd(pcb, NULL, 0, 0, 3 * TCP_MSS, TCP_ACK, TCP_MSS / 2);
test_tcp_input(p, &netif);
EXPECT(pcb->unacked == NULL);
EXPECT(pcb->unsent == NULL);
EXPECT(pcb->persist_backoff == 0);
EXPECT(pcb->snd_wnd == TCP_MSS / 2);
/* send fourth segment, which is larger than snd_wnd */
err = tcp_write(pcb, &tx_data[3 * TCP_MSS], TCP_MSS, TCP_WRITE_FLAG_COPY);
EXPECT(err == ERR_OK);
err = tcp_output(pcb);
EXPECT(err == ERR_OK);
/* ensure it is buffered and persist timer started */
EXPECT(pcb->unacked == NULL);
EXPECT(pcb->unsent != NULL);
check_seqnos(pcb->unsent, 1, &seqnos[3]);
EXPECT(txcounters.num_tx_calls == 0);
EXPECT(txcounters.num_tx_bytes == 0);
EXPECT(pcb->persist_backoff == 1);
/* ensure no errors have been recorded */
EXPECT(counters.err_calls == 0);
EXPECT(counters.last_err == ERR_OK);
/* call tcp_timer some more times to let persist timer count up */
for (i = 0; i < 4; i++) {
test_tcp_tmr();
EXPECT(txcounters.num_tx_calls == 0);
EXPECT(txcounters.num_tx_bytes == 0);
}
/* this should be the first timer shot, which should split the
* segment and send a runt (of the remaining window size) */
txcounters.copy_tx_packets = 1;
test_tcp_tmr();
txcounters.copy_tx_packets = 0;
/* persist will be disabled as RTO timer takes over */
EXPECT(pcb->persist_backoff == 0);
EXPECT(txcounters.num_tx_calls == 1);
EXPECT(txcounters.num_tx_bytes == ((TCP_MSS /2) + 40U));
/* verify half segment sent, half still buffered */
EXPECT(pcb->unsent != NULL);
EXPECT(pcb->unsent->len == TCP_MSS / 2);
EXPECT(pcb->unacked != NULL);
EXPECT(pcb->unacked->len == TCP_MSS / 2);
/* verify first half segment */
EXPECT(txcounters.tx_packets != NULL);
if (txcounters.tx_packets != NULL) {
u8_t sent[TCP_MSS / 2];
u16_t ret;
ret = pbuf_copy_partial(txcounters.tx_packets, &sent, TCP_MSS / 2, 40U);
EXPECT(ret == TCP_MSS / 2);
EXPECT(memcmp(sent, &tx_data[3 * TCP_MSS], TCP_MSS / 2) == 0);
}
if (txcounters.tx_packets != NULL) {
pbuf_free(txcounters.tx_packets);
txcounters.tx_packets = NULL;
}
memset(&txcounters, 0, sizeof(txcounters));
/* ACK the half segment, leave window at half segment */
p = tcp_create_rx_segment_wnd(pcb, NULL, 0, 0, TCP_MSS / 2, TCP_ACK, TCP_MSS / 2);
txcounters.copy_tx_packets = 1;
test_tcp_input(p, &netif);
txcounters.copy_tx_packets = 0;
/* ensure remaining half segment was sent */
EXPECT(txcounters.num_tx_calls == 1);
EXPECT(txcounters.num_tx_bytes == ((TCP_MSS /2 ) + 40U));
EXPECT(pcb->unsent == NULL);
EXPECT(pcb->unacked != NULL);
EXPECT(pcb->unacked->len == TCP_MSS / 2);
EXPECT(pcb->snd_wnd == TCP_MSS / 2);
/* verify second half segment */
EXPECT(txcounters.tx_packets != NULL);
if (txcounters.tx_packets != NULL) {
u8_t sent[TCP_MSS / 2];
u16_t ret;
ret = pbuf_copy_partial(txcounters.tx_packets, &sent, TCP_MSS / 2, 40U);
EXPECT(ret == TCP_MSS / 2);
EXPECT(memcmp(sent, &tx_data[(3 * TCP_MSS) + TCP_MSS / 2], TCP_MSS / 2) == 0);
}
if (txcounters.tx_packets != NULL) {
pbuf_free(txcounters.tx_packets);
txcounters.tx_packets = NULL;
}
/* ensure no errors have been recorded */
EXPECT(counters.err_calls == 0);
EXPECT(counters.last_err == ERR_OK);
/* make sure the pcb is freed */
EXPECT_RET(MEMP_STATS_GET(used, MEMP_TCP_PCB) == 1);
tcp_abort(pcb);
EXPECT_RET(MEMP_STATS_GET(used, MEMP_TCP_PCB) == 0);
}
END_TEST
/** Send data with sequence numbers that wrap around the u32_t range.
* Then, provoke RTO retransmission and check that all
* segment lists are still properly sorted. */
START_TEST(test_tcp_rto_rexmit_wraparound)
{
struct netif netif;
struct test_tcp_txcounters txcounters;
struct test_tcp_counters counters;
struct tcp_pcb* pcb;
err_t err;
size_t i;
u16_t sent_total = 0;
LWIP_UNUSED_ARG(_i);
for (i = 0; i < sizeof(tx_data); i++) {
tx_data[i] = (u8_t)i;
}
/* initialize local vars */
test_tcp_init_netif(&netif, &txcounters, &test_local_ip, &test_netmask);
memset(&counters, 0, sizeof(counters));
/* create and initialize the pcb */
tcp_ticks = 0;
tcp_ticks = 0 - tcp_next_iss(NULL);
tcp_ticks = SEQNO1 - tcp_next_iss(NULL);
pcb = test_tcp_new_counters_pcb(&counters);
EXPECT_RET(pcb != NULL);
tcp_set_state(pcb, ESTABLISHED, &test_local_ip, &test_remote_ip, TEST_LOCAL_PORT, TEST_REMOTE_PORT);
pcb->mss = TCP_MSS;
/* disable initial congestion window (we don't send a SYN here...) */
pcb->cwnd = 2*TCP_MSS;
/* send 6 mss-sized segments */
for (i = 0; i < 6; i++) {
err = tcp_write(pcb, &tx_data[sent_total], TCP_MSS, TCP_WRITE_FLAG_COPY);
EXPECT_RET(err == ERR_OK);
sent_total += TCP_MSS;
}
check_seqnos(pcb->unsent, 6, seqnos);
EXPECT(pcb->unacked == NULL);
err = tcp_output(pcb);
EXPECT(txcounters.num_tx_calls == 2);
EXPECT(txcounters.num_tx_bytes == 2 * (TCP_MSS + 40U));
memset(&txcounters, 0, sizeof(txcounters));
check_seqnos(pcb->unacked, 2, seqnos);
check_seqnos(pcb->unsent, 4, &seqnos[2]);
/* call the tcp timer some times */
for (i = 0; i < 10; i++) {
test_tcp_tmr();
EXPECT(txcounters.num_tx_calls == 0);
}
/* 11th call to tcp_tmr: RTO rexmit fires */
test_tcp_tmr();
EXPECT(txcounters.num_tx_calls == 1);
check_seqnos(pcb->unacked, 1, seqnos);
check_seqnos(pcb->unsent, 5, &seqnos[1]);
/* fake greater cwnd */
pcb->cwnd = pcb->snd_wnd;
/* send more data */
err = tcp_output(pcb);
EXPECT(err == ERR_OK);
/* check queues are sorted */
EXPECT(pcb->unsent == NULL);
check_seqnos(pcb->unacked, 6, seqnos);
/* make sure the pcb is freed */
EXPECT_RET(MEMP_STATS_GET(used, MEMP_TCP_PCB) == 1);
tcp_abort(pcb);
EXPECT_RET(MEMP_STATS_GET(used, MEMP_TCP_PCB) == 0);
}
END_TEST
START_TEST(test_tcp_zwp_timeout)
{
struct netif netif;
struct test_tcp_txcounters txcounters;
struct test_tcp_counters counters;
struct tcp_pcb *pcb, *cur;
struct pbuf* p;
err_t err;
size_t i;
LWIP_UNUSED_ARG(_i);
/* Setup data for two segments */
for (i = 0; i < 2*TCP_MSS; i++) {
tx_data[i] = (u8_t)i;
}
/* initialize local vars */
test_tcp_init_netif(&netif, &txcounters, &test_local_ip, &test_netmask);
memset(&counters, 0, sizeof(counters));
/* create and initialize the pcb */
tcp_ticks = SEQNO1 - ISS;
pcb = test_tcp_new_counters_pcb(&counters);
EXPECT_RET(pcb != NULL);
tcp_set_state(pcb, ESTABLISHED, &test_local_ip, &test_remote_ip, TEST_LOCAL_PORT, TEST_REMOTE_PORT);
pcb->mss = TCP_MSS;
pcb->cwnd = TCP_MSS;
/* send first segment */
err = tcp_write(pcb, &tx_data[0], TCP_MSS, TCP_WRITE_FLAG_COPY);
EXPECT(err == ERR_OK);
err = tcp_output(pcb);
EXPECT(err == ERR_OK);
/* verify segment is in-flight */
EXPECT(pcb->unsent == NULL);
check_seqnos(pcb->unacked, 1, seqnos);
EXPECT(txcounters.num_tx_calls == 1);
EXPECT(txcounters.num_tx_bytes == 1 * (TCP_MSS + 40U));
memset(&txcounters, 0, sizeof(txcounters));
/* ACK the segment and close the TX window */
p = tcp_create_rx_segment_wnd(pcb, NULL, 0, 0, TCP_MSS, TCP_ACK, 0);
test_tcp_input(p, &netif);
EXPECT(pcb->unacked == NULL);
EXPECT(pcb->unsent == NULL);
/* send buffer empty, persist should be off */
EXPECT(pcb->persist_backoff == 0);
EXPECT(pcb->snd_wnd == 0);
/* send second segment, should be buffered */
err = tcp_write(pcb, &tx_data[TCP_MSS], TCP_MSS, TCP_WRITE_FLAG_COPY);
EXPECT(err == ERR_OK);
err = tcp_output(pcb);
EXPECT(err == ERR_OK);
/* ensure it is buffered and persist timer started */
EXPECT(pcb->unacked == NULL);
check_seqnos(pcb->unsent, 1, &seqnos[1]);
EXPECT(txcounters.num_tx_calls == 0);
EXPECT(txcounters.num_tx_bytes == 0);
EXPECT(pcb->persist_backoff == 1);
/* ensure no errors have been recorded */
EXPECT(counters.err_calls == 0);
EXPECT(counters.last_err == ERR_OK);
/* run timer till first probe */
EXPECT(pcb->persist_probe == 0);
while (pcb->persist_probe == 0) {
test_tcp_tmr();
}
EXPECT(txcounters.num_tx_calls == 1);
EXPECT(txcounters.num_tx_bytes == (1 + 40U));
memset(&txcounters, 0, sizeof(txcounters));
/* respond to probe with remote's current SEQ, ACK, and zero-window */
p = tcp_create_rx_segment_wnd(pcb, NULL, 0, 0, 0, TCP_ACK, 0);
test_tcp_input(p, &netif);
/* ensure zero-window is still active, but probe count reset */
EXPECT(pcb->persist_backoff > 1);
EXPECT(pcb->persist_probe == 0);
EXPECT(pcb->snd_wnd == 0);
/* ensure no errors have been recorded */
EXPECT(counters.err_calls == 0);
EXPECT(counters.last_err == ERR_OK);
/* now run the timer till we hit our maximum probe count */
while (counters.last_err == ERR_OK) {
test_tcp_tmr();
}
/* check maximum number of 1 byte probes were sent */
EXPECT(txcounters.num_tx_calls == TCP_MAXRTX);
EXPECT(txcounters.num_tx_bytes == TCP_MAXRTX * (1 + 40U));
/* check the connection (pcb) has been aborted */
EXPECT(counters.err_calls == 1);
EXPECT(counters.last_err == ERR_ABRT);
/* check our pcb is no longer active */
for (cur = tcp_active_pcbs; cur != NULL; cur = cur->next) {
EXPECT(cur != pcb);
}
EXPECT_RET(MEMP_STATS_GET(used, MEMP_TCP_PCB) == 0);
}
