tools/testing/selftests/net/packetdrill/tcp_accecn_notecn_then_accecn_syn.pkt

Source file repositories/reference/linux-study-clean/tools/testing/selftests/net/packetdrill/tcp_accecn_notecn_then_accecn_syn.pkt

File Facts

System
Linux kernel
Corpus path
tools/testing/selftests/net/packetdrill/tcp_accecn_notecn_then_accecn_syn.pkt
Extension
.pkt
Size
942 bytes
Lines
29
Domain
Support Tooling And Documentation
Bucket
tools
Inferred role
Support Tooling And Documentation: tools
Status
atlas-only

Why This File Exists

Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.

Dependency Surface

Detected Declarations

Annotated Snippet

// Test that SYN-ACK with ACE flags and without
// ACE flags got dropped. Although we disable ECN,
// we shouldn't consider this as blackholed as
// these are dropped due to congestion

`./defaults.sh
sysctl -q net.ipv4.tcp_ecn=3
sysctl -q net.ipv4.tcp_ecn_option=2
`

+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

+0 < [noecn] S 0:0(0) win 32792 <mss 1460,nop,nop,sackOK,nop,wscale 8>
+.002 > [noecn] S. 0:0(0) ack 1 <mss 1460,nop,nop,sackOK,nop,wscale 8>

// Retransmit SYN
+0.1 < [ect0] SEWA 0:0(0) win 32792 <mss 1460,nop,nop,sackOK,nop,wscale 8>
+.002 > [noecn] S. 0:0(0) ack 1 <mss 1460,nop,nop,sackOK,nop,wscale 8>

+0.1 < [noecn] . 1:1(0) ack 1 win 320
+.002 accept(3, ..., ...) = 4

// Write with AccECN option but with ip-noecn since we received one SYN with ACE=0
+0.01 write(4, ..., 100) = 100
+.002 > [noecn] P. 1:101(100) ack 1

Annotation

Implementation Notes