summaryrefslogtreecommitdiff
path: root/tools/testing/selftests/net/packetdrill/tcp_ecn_ecn-uses-ect0.pkt
diff options
context:
space:
mode:
Diffstat (limited to 'tools/testing/selftests/net/packetdrill/tcp_ecn_ecn-uses-ect0.pkt')
-rw-r--r--tools/testing/selftests/net/packetdrill/tcp_ecn_ecn-uses-ect0.pkt21
1 files changed, 21 insertions, 0 deletions
diff --git a/tools/testing/selftests/net/packetdrill/tcp_ecn_ecn-uses-ect0.pkt b/tools/testing/selftests/net/packetdrill/tcp_ecn_ecn-uses-ect0.pkt
new file mode 100644
index 000000000000..643baf3267cf
--- /dev/null
+++ b/tools/testing/selftests/net/packetdrill/tcp_ecn_ecn-uses-ect0.pkt
@@ -0,0 +1,21 @@
+// SPDX-License-Identifier: GPL-2.0
+// Test ECN: verify that Linux TCP ECN sending code uses ECT0 (not ECT1).
+//
+`./defaults.sh
+sysctl -q net.ipv4.tcp_ecn=1 # fully enabled
+`
+
+// Initialize connection
+ 0 socket(..., SOCK_STREAM, IPPROTO_TCP) = 4
+
+// ECN handshake: send EW flags in SYN packet, E flag in SYN-ACK response
++.002 ... 0.004 connect(4, ..., ...) = 0
+
+ +0 > SEW 0:0(0) <mss 1460,sackOK,TS val 100 ecr 0,nop,wscale 8>
++.002 < SE. 0:0(0) ack 1 win 32767 <mss 1000,nop,wscale 6,nop,nop,sackOK>
+ +0 > . 1:1(0) ack 1
+
+// Write 1 MSS.
++.002 write(4, ..., 1000) = 1000
+// Send 1 MSS with ect0.
+ +0 > [ect0] P. 1:1001(1000) ack 1