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shivansh/TCPS_HAVERCVDFIN.txt

Last active September 23, 2016 19:02
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Raw
close-half-open-tcpdump
tcpdump: verbose output suppressed, use -v or -vv for full protocol decode
listening on tun0, link-type NULL (BSD loopback), capture size 262144 bytes
05:59:55.381693 IP 192.0.2.1.47963 > 192.168.0.1.8080: Flags [S], seq 0, win 65535, options [mss 1460,sackOK,nop,nop,nop,wscale 7], length 0
05:59:55.381717 IP 192.168.0.1.8080 > 192.0.2.1.47963: Flags [S.], seq 3379463730, ack 1, win 65535, options [mss 1460,nop,wscale 6,sackOK,eol], length 0
05:59:55.382710 IP 192.0.2.1.47963 > 192.168.0.1.8080: Flags [.], ack 1, win 65535, length 0
05:59:55.383863 IP 192.0.2.1.47963 > 192.168.0.1.8080: Flags [F.], seq 1, ack 1, win 65535, length 0
05:59:55.383877 IP 192.168.0.1.8080 > 192.0.2.1.47963: Flags [.], ack 2, win 1026, length 0
05:59:55.584821 IP6 :: > ff02::16: HBH ICMP6, multicast listener report v2, 1 group record(s), length 28
05:59:55.796828 IP6 :: > ff02::16: HBH ICMP6, multicast listener report v2, 2 group record(s), length 48
05:59:55.982448 IP6 :: > ff02::1:ffa0:b9e2: ICMP6, neighbor solicitation, who has fe80::a00:27ff:fea0:b9e2, length 32
05:59:56.220824 IP6 :: > ff02::16: HBH ICMP6, multicast listener report v2, 1 group record(s), length 28
05:59:57.916822 IP6 fe80::a00:27ff:fea0:b9e2 > ff02::16: HBH ICMP6, multicast listener report v2, 2 group record(s), length 48
06:00:09.936582 IP 192.168.0.1.8080 > 192.0.2.1.16730: Flags [R.], seq 169419763, ack 1, win 1026, length 0
06:00:13.911574 IP 192.168.0.1.8080 > 192.0.2.1.48548: Flags [F.], seq 309313001, ack 1, win 1026, length 0
06:00:47.379576 IP 192.168.0.1.8080 > 192.0.2.1.39061: Flags [F.], seq 1171129280, ack 1, win 1026, length 0
06:01:17.928589 IP 192.168.0.1.8080 > 192.0.2.1.48548: Flags [F.], seq 0, ack 1, win 1026, length 0
Raw
close-half-open.pkt
// Create a listening TCP socket
0.000 socket(..., SOCK_STREAM, IPPROTO_TCP) = 3
0.000 setsockopt(3, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 0
0.000 bind(3, ..., ...) = 0
0.000 listen(3, 1) = 0
// Establish a connection
0.100 < S 0:0(0) win 65535 <mss 1460,sackOK,nop,nop,nop,wscale 7>
0.100 > S. 0:0(0) ack 1 <...>
0.100 < . 1:1(0) ack 1 win 65535
0.100 accept(3, ..., ...) = 4
// 0.100 close(4) = 0
// 0.100 > F. 1:1(0) ack 1 <...>
//
0.110 < F. 1:1(0) ack 1 win 65535
// Observation 1 : Even when we are not sending the following ACK, the TCP
// stack will automatically send the ACK, as intercepted by tcpdump.
0.110 > . 1:1(0) ack 2 <...>
// The following ACK has to be removed.
// 0.110 < . 2:2(0) ack 2 win 65535
// The client skips the ACK (last ACK lost)
// We now try to close the connection from the other side first.
// 0.110 < F. 1:1(0) ack 1 win 65535
0.110 > F. 1:1(0) ack 2 <...>
Raw
rto.pkt
// Test for Retransmission Timeout with 10 packets outstanding.
// Receiver in this case supports Sack.
// Create a listening TCP socket
0.000 socket(..., SOCK_STREAM, IPPROTO_TCP) = 3
0.000 setsockopt(3, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 0
0.000 bind(3, ..., ...) = 0
0.000 listen(3, 1) = 0
// Establish a connection
0.100 < S 0:0(0) win 65535 <mss 1000,sackOK,nop,nop,nop,wscale 7>
0.100 > S. 0:0(0) ack 1 <...>
0.100 < . 1:1(0) ack 1 win 65535
0.100 accept(3, ..., ...) = 4
0.110 %{ assert tcpi_rto == 3000000 }%
// We write 10 data segments
0.110 write(4, ..., 10000) = 10000
0.110 > . 1:1001(1000) ack 1
0.110 > . 1001:2001(1000) ack 1
0.110 > . 2001:3001(1000) ack 1
0.110 > . 3001:4001(1000) ack 1
0.110 > . 4001:5001(1000) ack 1
0.110 > . 5001:6001(1000) ack 1
0.110 > . 6001:7001(1000) ack 1
0.110 > . 7001:8001(1000) ack 1
0.110 > . 8001:9001(1000) ack 1
0.110 > P. 9001:10001(1000) ack 1
// Client ACKs first 4 data segments
0.120 < . 1:1(0) ack 4001 win 65535 <sack 1:4001, nop, nop>
0.320 %{ assert tcpi_rto == 230000 }%
// Retransmission timeout occurs
0.320 > . 4001:5001(1000) ack 1
// Retransmission timeout occurs
0.620 > . 4001:5001(1000) ack 1
=================================================================
The output of the test -
▶ sudo ./packetdrill -v --tolerance_usecs=100000 ~/soc-16/rto/retransmission_timeout.pkt
inbound injected packet: 0.106955 S 0:0(0) win 65535 <mss 1000,sackOK,nop,nop,nop,wscale 7>
outbound sniffed packet: 0.107372 S. 644337437:644337437(0) ack 1 win 65535 <mss 1000,nop,wscale 6,sackOK,eol,eol>
inbound injected packet: 0.107718 . 1:1(0) ack 644337438 win 65535
outbound sniffed packet: 0.110271 . 644337438:644338438(1000) ack 1 win 1031
outbound sniffed packet: 0.110281 . 644338438:644339438(1000) ack 1 win 1031
outbound sniffed packet: 0.110287 . 644339438:644340438(1000) ack 1 win 1031
outbound sniffed packet: 0.110292 . 644340438:644341438(1000) ack 1 win 1031
outbound sniffed packet: 0.110299 . 644341438:644342438(1000) ack 1 win 1031
outbound sniffed packet: 0.110304 . 644342438:644343438(1000) ack 1 win 1031
outbound sniffed packet: 0.110310 . 644343438:644344438(1000) ack 1 win 1031
outbound sniffed packet: 0.110315 . 644344438:644345438(1000) ack 1 win 1031
outbound sniffed packet: 0.110320 . 644345438:644346438(1000) ack 1 win 1031
outbound sniffed packet: 0.110326 P. 644346438:644347438(1000) ack 1 win 1031
inbound injected packet: 0.120323 . 1:1(0) ack 644341438 win 65535 <sack 644337438:644341438,nop,nop>
outbound sniffed packet: 0.364135 . 644341438:644342438(1000) ack 1 win 1031
outbound sniffed packet: 0.640008 . 644341438:644342438(1000) ack 1 win 1031
tcpi_rto = 3000000
The value drops -
tcpi_rto = 230000
Raw
shutdown-wr.pkt
// Borrowed from https://github.com/google/packetdrill
// This test checks for the behavior of the sequence
// shutdown(SHUT_RD), read, shutdown(SHUT_WR), write(), close()
--tolerance_usecs=100000
// Establish the connection
0.000 socket(..., SOCK_STREAM, IPPROTO_TCP) = 3
0.000 setsockopt(3, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 0
0.000 bind(3, ..., ...) = 0
0.000 listen(3, 1) = 0
0.100 < S 0:0(0) win 65535 <mss 1460,sackOK,nop,nop,nop,wscale 7>
0.100 > S. 0:0(0) ack 1 <...>
0.200 < . 1:1(0) ack 1 win 65535
0.200 accept(3, ..., ...) = 4
0.210 shutdown(4, SHUT_WR) = 0
0.210 write(4, ..., 1000) = -1 EPIPE (Broken pipe)
0.210 > F. 1:1(0) ack 1
0.210 < . 1:1(0) ack 2 win 65535
0.220 < F. 1:1(0) ack 2 win 65535
0.220 > . 2:2(0) ack 2
Raw
TCPS_HAVERCVDFIN.txt
sys/ofed/drivers/infiniband/ulp/sdp/sdp_rx.c
47: if (TCPS_HAVERCVDFIN(ssk->state) == 0)
444: TCPS_HAVERCVDFIN(ssk->state)) {
sys/netinet/tcp_fsm.h
76:#define TCPS_HAVERCVDFIN(s) ((s) >= TCPS_TIME_WAIT)
sys/netinet/tcp_stacks/fastpath.c
1050: (TCPS_HAVERCVDFIN(tp->t_state) == 0)) {
1450: TCPS_HAVERCVDFIN(tp->t_state) == 0) {
1520: TCPS_HAVERCVDFIN(tp->t_state) == 0) {
1587: if (TCPS_HAVERCVDFIN(tp->t_state) == 0) {
sys/netinet/tcp_input.c
2523: (TCPS_HAVERCVDFIN(tp->t_state) == 0)) {
2954: TCPS_HAVERCVDFIN(tp->t_state) == 0) {
3026: TCPS_HAVERCVDFIN(tp->t_state) == 0) {
3094: if (TCPS_HAVERCVDFIN(tp->t_state) == 0) {
sys/netinet/tcp_output.c
640: !TCPS_HAVERCVDFIN(tp->t_state)) {
Raw
time-wait.pkt
// Test for establishing TIME_WAIT configuration.
--tolerance_usecs=100000
// Create a listening TCP socket
0.000 socket(..., SOCK_STREAM, IPPROTO_TCP) = 3
0.000 setsockopt(3, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 0
0.000 bind(3, ..., ...) = 0
0.000 listen(3, 1) = 0
// Establish a connection
0.100 < S 0:0(0) win 65535 <mss 1460,sackOK,nop,nop,nop,wscale 7>
0.100 > S. 0:0(0) ack 1 win 65535 <...>
0.100 < . 1:1(0) ack 1 win 65535
0.100 accept(3, ..., ...) = 4
// We make a transition to FIN_WAIT_1.
0.100 close(4) = 0
0.100 > F. 1:1(0) ack 1 <...>
+0 %{ assert tcpi_state == TCPS_FIN_WAIT1 }%
// We make a transition to FIN_WAIT_2.
0.110 < . 1:1(0) ack 2 win 65535
0.110 < F. 1:1(0) ack 2 win 65535
0.120 > . 2:2(0) ack 2 <...>
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