diff options
Diffstat (limited to 'tools/testing/selftests/net/packetdrill/tcp_limited_transmit_limited-transmit-no-sack.pkt')
| -rw-r--r-- | tools/testing/selftests/net/packetdrill/tcp_limited_transmit_limited-transmit-no-sack.pkt | 53 |
1 files changed, 53 insertions, 0 deletions
diff --git a/tools/testing/selftests/net/packetdrill/tcp_limited_transmit_limited-transmit-no-sack.pkt b/tools/testing/selftests/net/packetdrill/tcp_limited_transmit_limited-transmit-no-sack.pkt new file mode 100644 index 000000000000..96b01eb5b7a4 --- /dev/null +++ b/tools/testing/selftests/net/packetdrill/tcp_limited_transmit_limited-transmit-no-sack.pkt @@ -0,0 +1,53 @@ +// SPDX-License-Identifier: GPL-2.0 +// Test RFC 3042 "Limited Transmit": "sending a new data segment in +// response to each of the first two duplicate acknowledgments that +// arrive at the sender". +// This variation tests a receiver that doesn't support SACK. + +`./defaults.sh` + +// Establish a connection. + 0 socket(..., SOCK_STREAM, IPPROTO_TCP) = 3 + +0 setsockopt(3, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 0 + +0 bind(3, ..., ...) = 0 + +0 listen(3, 1) = 0 + + +.1 < S 0:0(0) win 32792 <mss 1000,nop,wscale 7> + +0 > S. 0:0(0) ack 1 <mss 1460,nop,wscale 8> + +.1 < . 1:1(0) ack 1 win 320 + +0 accept(3, ..., ...) = 4 + +// Write some data, and send the initial congestion window. + +0 write(4, ..., 15000) = 15000 + +0 > P. 1:10001(10000) ack 1 + +// Limited transmit: on first dupack, send a new data segment. + +.11 < . 1:1(0) ack 1 win 320 + +0 > . 10001:11001(1000) ack 1 + +// Limited transmit: on second dupack, send a new data segment. + +.01 < . 1:1(0) ack 1 win 320 + +0 > . 11001:12001(1000) ack 1 + +// It turned out to be reordering, not loss. +// We have one packet newly acked (1001:3001 were DUP-ACK'd) +// So we revert state back to Open. Slow start cwnd from 10 to 11 +// and send 11 - 9 = 2 packets + +.01 < . 1:1(0) ack 3001 win 320 + +0 > P. 12001:14001(2000) ack 1 + + +.02 < . 1:1(0) ack 5001 win 320 + +0 > P. 14001:15001(1000) ack 1 + +// Client gradually ACKs all data. + +.02 < . 1:1(0) ack 7001 win 320 + +.02 < . 1:1(0) ack 9001 win 320 + +.02 < . 1:1(0) ack 11001 win 320 + +.02 < . 1:1(0) ack 13001 win 320 + +.02 < . 1:1(0) ack 15001 win 320 + +// Clean up. + +.17 close(4) = 0 + +0 > F. 15001:15001(0) ack 1 + +.1 < F. 1:1(0) ack 15002 win 257 + +0 > . 15002:15002(0) ack 2 |