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

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

File Facts

System
Linux kernel
Corpus path
tools/testing/selftests/net/packetdrill/tcp_inq_server.pkt
Extension
.pkt
Size
1701 bytes
Lines
55
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

// SPDX-License-Identifier: GPL-2.0
// Test TCP_INQ and TCP_CM_INQ on the server side.

--mss=1000

`./defaults.sh
`

// Initialize 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

   +0	< S 0:0(0) win 32792 <mss 1000,sackOK,nop,nop,nop,wscale 10>
   +0	> S. 0:0(0) ack 1 <mss 1460,nop,nop,sackOK,nop,wscale 8>
 +.01	< . 1:1(0) ack 1 win 514

// Accept the connection and enable TCP_INQ.
   +0	accept(3, ..., ...) = 4
   +0	setsockopt(4, SOL_TCP, TCP_INQ, [1], 4) = 0

// Now we have 10K of data ready on the socket.
   +0	< . 1:10001(10000) ack 1 win 514
   +0	> . 1:1(0) ack 10001

// We read 2K and we should have 8K ready to read.
   +0	recvmsg(4, {msg_name(...)=...,
		    msg_iov(1)=[{..., 2000}],
		    msg_flags=0,
		    msg_control=[{cmsg_level=SOL_TCP,
				  cmsg_type=TCP_CM_INQ,
				  cmsg_data=8000}]}, 0) = 2000
// We read 8K and we should have no further data ready to read.
   +0	recvmsg(4, {msg_name(...)=...,
		    msg_iov(1)=[{..., 8000}],
		    msg_flags=0,
		    msg_control=[{cmsg_level=SOL_TCP,
				  cmsg_type=TCP_CM_INQ,
				  cmsg_data=0}]}, 0) = 8000
// Client sends more data and closes the connections.
   +0	< F. 10001:20001(10000) ack 1 win 514
   +0	> . 1:1(0) ack 20002

// We read 10K and we should have one "fake" byte because the connection is
// closed.
   +0	recvmsg(4, {msg_name(...)=...,
		    msg_iov(1)=[{..., 10000}],
		    msg_flags=0,
		    msg_control=[{cmsg_level=SOL_TCP,
				  cmsg_type=TCP_CM_INQ,
				  cmsg_data=1}]}, 0) = 10000
// Now, receive error.
   +0	read(3, ..., 2000) = -1 ENOTCONN (Transport endpoint is not connected)

Annotation

Implementation Notes