Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
linux
1#!/usr/bin/env bash
2# SPDX-License-Identifier: GPL-2.0
3
4# This test creates two netdevsim virtual interfaces, assigns one of them (the
5# "destination interface") to a new namespace, and assigns IP addresses to both
6# interfaces.
7#
8# It listens on the destination interface using socat and configures a dynamic
9# target on netconsole, pointing to the destination IP address.
10#
11# Finally, it checks whether the message was received properly on the
12# destination interface. Note that this test may pollute the kernel log buffer
13# (dmesg) and relies on dynamic configuration and namespaces being configured.
14#
15# Author: Breno Leitao <leitao@debian.org>
16
17set -euo pipefail
18
19SCRIPTDIR=$(dirname "$(readlink -e "${BASH_SOURCE[0]}")")
20
21# Simple script to test dynamic targets in netconsole
22SRCIF="" # to be populated later
23SRCIP=192.168.1.1
24DSTIF="" # to be populated later
25DSTIP=192.168.1.2
26
27PORT="6666"
28MSG="netconsole selftest"
29TARGET=$(mktemp -u netcons_XXXXX)
30DEFAULT_PRINTK_VALUES=$(cat /proc/sys/kernel/printk)
31NETCONS_CONFIGFS="/sys/kernel/config/netconsole"
32NETCONS_PATH="${NETCONS_CONFIGFS}"/"${TARGET}"
33# NAMESPACE will be populated by setup_ns with a random value
34NAMESPACE=""
35
36# IDs for netdevsim
37NSIM_DEV_1_ID=$((256 + RANDOM % 256))
38NSIM_DEV_2_ID=$((512 + RANDOM % 256))
39
40# Used to create and delete namespaces
41source "${SCRIPTDIR}"/../../net/lib.sh
42source "${SCRIPTDIR}"/../../net/net_helper.sh
43
44# Create netdevsim interfaces
45create_ifaces() {
46 local NSIM_DEV_SYS_NEW=/sys/bus/netdevsim/new_device
47
48 echo "$NSIM_DEV_2_ID" > "$NSIM_DEV_SYS_NEW"
49 echo "$NSIM_DEV_1_ID" > "$NSIM_DEV_SYS_NEW"
50 udevadm settle 2> /dev/null || true
51
52 local NSIM1=/sys/bus/netdevsim/devices/netdevsim"$NSIM_DEV_1_ID"
53 local NSIM2=/sys/bus/netdevsim/devices/netdevsim"$NSIM_DEV_2_ID"
54
55 # These are global variables
56 SRCIF=$(find "$NSIM1"/net -maxdepth 1 -type d ! \
57 -path "$NSIM1"/net -exec basename {} \;)
58 DSTIF=$(find "$NSIM2"/net -maxdepth 1 -type d ! \
59 -path "$NSIM2"/net -exec basename {} \;)
60}
61
62link_ifaces() {
63 local NSIM_DEV_SYS_LINK="/sys/bus/netdevsim/link_device"
64 local SRCIF_IFIDX=$(cat /sys/class/net/"$SRCIF"/ifindex)
65 local DSTIF_IFIDX=$(cat /sys/class/net/"$DSTIF"/ifindex)
66
67 exec {NAMESPACE_FD}</var/run/netns/"${NAMESPACE}"
68 exec {INITNS_FD}</proc/self/ns/net
69
70 # Bind the dst interface to namespace
71 ip link set "${DSTIF}" netns "${NAMESPACE}"
72
73 # Linking one device to the other one (on the other namespace}
74 if ! echo "${INITNS_FD}:$SRCIF_IFIDX $NAMESPACE_FD:$DSTIF_IFIDX" > $NSIM_DEV_SYS_LINK
75 then
76 echo "linking netdevsim1 with netdevsim2 should succeed"
77 cleanup
78 exit "${ksft_skip}"
79 fi
80}
81
82function configure_ip() {
83 # Configure the IPs for both interfaces
84 ip netns exec "${NAMESPACE}" ip addr add "${DSTIP}"/24 dev "${DSTIF}"
85 ip netns exec "${NAMESPACE}" ip link set "${DSTIF}" up
86
87 ip addr add "${SRCIP}"/24 dev "${SRCIF}"
88 ip link set "${SRCIF}" up
89}
90
91function set_network() {
92 # setup_ns function is coming from lib.sh
93 setup_ns NAMESPACE
94
95 # Create both interfaces, and assign the destination to a different
96 # namespace
97 create_ifaces
98
99 # Link both interfaces back to back
100 link_ifaces
101
102 configure_ip
103}
104
105function create_dynamic_target() {
106 DSTMAC=$(ip netns exec "${NAMESPACE}" \
107 ip link show "${DSTIF}" | awk '/ether/ {print $2}')
108
109 # Create a dynamic target
110 mkdir "${NETCONS_PATH}"
111
112 echo "${DSTIP}" > "${NETCONS_PATH}"/remote_ip
113 echo "${SRCIP}" > "${NETCONS_PATH}"/local_ip
114 echo "${DSTMAC}" > "${NETCONS_PATH}"/remote_mac
115 echo "${SRCIF}" > "${NETCONS_PATH}"/dev_name
116
117 echo 1 > "${NETCONS_PATH}"/enabled
118}
119
120function cleanup() {
121 local NSIM_DEV_SYS_DEL="/sys/bus/netdevsim/del_device"
122
123 # delete netconsole dynamic reconfiguration
124 echo 0 > "${NETCONS_PATH}"/enabled
125 # Remove the configfs entry
126 rmdir "${NETCONS_PATH}"
127
128 # Delete netdevsim devices
129 echo "$NSIM_DEV_2_ID" > "$NSIM_DEV_SYS_DEL"
130 echo "$NSIM_DEV_1_ID" > "$NSIM_DEV_SYS_DEL"
131
132 # this is coming from lib.sh
133 cleanup_all_ns
134
135 # Restoring printk configurations
136 echo "${DEFAULT_PRINTK_VALUES}" > /proc/sys/kernel/printk
137}
138
139function listen_port_and_save_to() {
140 local OUTPUT=${1}
141 # Just wait for 2 seconds
142 timeout 2 ip netns exec "${NAMESPACE}" \
143 socat UDP-LISTEN:"${PORT}",fork "${OUTPUT}"
144}
145
146function validate_result() {
147 local TMPFILENAME="$1"
148
149 # Check if the file exists
150 if [ ! -f "$TMPFILENAME" ]; then
151 echo "FAIL: File was not generated." >&2
152 exit "${ksft_fail}"
153 fi
154
155 if ! grep -q "${MSG}" "${TMPFILENAME}"; then
156 echo "FAIL: ${MSG} not found in ${TMPFILENAME}" >&2
157 cat "${TMPFILENAME}" >&2
158 exit "${ksft_fail}"
159 fi
160
161 # Delete the file once it is validated, otherwise keep it
162 # for debugging purposes
163 rm "${TMPFILENAME}"
164 exit "${ksft_pass}"
165}
166
167function check_for_dependencies() {
168 if [ "$(id -u)" -ne 0 ]; then
169 echo "This test must be run as root" >&2
170 exit "${ksft_skip}"
171 fi
172
173 if ! which socat > /dev/null ; then
174 echo "SKIP: socat(1) is not available" >&2
175 exit "${ksft_skip}"
176 fi
177
178 if ! which ip > /dev/null ; then
179 echo "SKIP: ip(1) is not available" >&2
180 exit "${ksft_skip}"
181 fi
182
183 if ! which udevadm > /dev/null ; then
184 echo "SKIP: udevadm(1) is not available" >&2
185 exit "${ksft_skip}"
186 fi
187
188 if [ ! -d "${NETCONS_CONFIGFS}" ]; then
189 echo "SKIP: directory ${NETCONS_CONFIGFS} does not exist. Check if NETCONSOLE_DYNAMIC is enabled" >&2
190 exit "${ksft_skip}"
191 fi
192
193 if ip link show "${DSTIF}" 2> /dev/null; then
194 echo "SKIP: interface ${DSTIF} exists in the system. Not overwriting it." >&2
195 exit "${ksft_skip}"
196 fi
197
198 if ip addr list | grep -E "inet.*(${SRCIP}|${DSTIP})" 2> /dev/null; then
199 echo "SKIP: IPs already in use. Skipping it" >&2
200 exit "${ksft_skip}"
201 fi
202}
203
204# ========== #
205# Start here #
206# ========== #
207modprobe netdevsim 2> /dev/null || true
208modprobe netconsole 2> /dev/null || true
209
210# The content of kmsg will be save to the following file
211OUTPUT_FILE="/tmp/${TARGET}"
212
213# Check for basic system dependency and exit if not found
214check_for_dependencies
215# Set current loglevel to KERN_INFO(6), and default to KERN_NOTICE(5)
216echo "6 5" > /proc/sys/kernel/printk
217# Remove the namespace, interfaces and netconsole target on exit
218trap cleanup EXIT
219# Create one namespace and two interfaces
220set_network
221# Create a dynamic target for netconsole
222create_dynamic_target
223# Listed for netconsole port inside the namespace and destination interface
224listen_port_and_save_to "${OUTPUT_FILE}" &
225# Wait for socat to start and listen to the port.
226wait_local_port_listen "${NAMESPACE}" "${PORT}" udp
227# Send the message
228echo "${MSG}: ${TARGET}" > /dev/kmsg
229# Wait until socat saves the file to disk
230busywait "${BUSYWAIT_TIMEOUT}" test -s "${OUTPUT_FILE}"
231
232# Make sure the message was received in the dst part
233# and exit
234validate_result "${OUTPUT_FILE}"