1#!/bin/bash
2# SPDX-License-Identifier: GPL-2.0
3#
4# Tests sysctl options {arp,ndisc}_evict_nocarrier={0,1}
5#
6# Create a veth pair and set IPs/routes on both. Then ping to establish
7# an entry in the ARP/ND table. Depending on the test set sysctl option to
8# 1 or 0. Set remote veth down which will cause local veth to go into a no
9# carrier state. Depending on the test check the ARP/ND table:
10#
11# {arp,ndisc}_evict_nocarrier=1 should contain no ARP/ND after no carrier
12# {arp,ndisc}_evict_nocarrer=0 should still contain the single ARP/ND entry
13#
14
15readonly PEER_NS="ns-peer-$(mktemp -u XXXXXX)"
16readonly V4_ADDR0=10.0.10.1
17readonly V4_ADDR1=10.0.10.2
18readonly V6_ADDR0=2001:db8:91::1
19readonly V6_ADDR1=2001:db8:91::2
20nsid=100
21
22cleanup_v6()
23{
24    ip netns del me
25    ip netns del peer
26
27    sysctl -w net.ipv4.conf.veth0.ndisc_evict_nocarrier=1 >/dev/null 2>&1
28    sysctl -w net.ipv4.conf.all.ndisc_evict_nocarrier=1 >/dev/null 2>&1
29}
30
31create_ns()
32{
33    local n=${1}
34
35    ip netns del ${n} 2>/dev/null
36
37    ip netns add ${n}
38    ip netns set ${n} $((nsid++))
39    ip -netns ${n} link set lo up
40}
41
42
43setup_v6() {
44    create_ns me
45    create_ns peer
46
47    IP="ip -netns me"
48
49    $IP li add veth1 type veth peer name veth2
50    $IP li set veth1 up
51    $IP -6 addr add $V6_ADDR0/64 dev veth1 nodad
52    $IP li set veth2 netns peer up
53    ip -netns peer -6 addr add $V6_ADDR1/64 dev veth2 nodad
54
55    ip netns exec me sysctl -w $1 >/dev/null 2>&1
56
57    # Establish an ND cache entry
58    ip netns exec me ping -6 -c1 -Iveth1 $V6_ADDR1 >/dev/null 2>&1
59    # Should have the veth1 entry in ND table
60    ip netns exec me ip -6 neigh get $V6_ADDR1 dev veth1 >/dev/null 2>&1
61    if [ $? -ne 0 ]; then
62        cleanup_v6
63        echo "failed"
64        exit
65    fi
66
67    # Set veth2 down, which will put veth1 in NOCARRIER state
68    ip netns exec peer ip link set veth2 down
69}
70
71setup_v4() {
72    ip netns add "${PEER_NS}"
73    ip link add name veth0 type veth peer name veth1
74    ip link set dev veth0 up
75    ip link set dev veth1 netns "${PEER_NS}"
76    ip netns exec "${PEER_NS}" ip link set dev veth1 up
77    ip addr add $V4_ADDR0/24 dev veth0
78    ip netns exec "${PEER_NS}" ip addr add $V4_ADDR1/24 dev veth1
79    ip netns exec ${PEER_NS} ip route add default via $V4_ADDR1 dev veth1
80    ip route add default via $V4_ADDR0 dev veth0
81
82    sysctl -w "$1" >/dev/null 2>&1
83
84    # Establish an ARP cache entry
85    ping -c1 -I veth0 $V4_ADDR1 -q >/dev/null 2>&1
86    # Should have the veth1 entry in ARP table
87    ip neigh get $V4_ADDR1 dev veth0 >/dev/null 2>&1
88    if [ $? -ne 0 ]; then
89        cleanup_v4
90        echo "failed"
91        exit
92    fi
93
94    # Set veth1 down, which will put veth0 in NOCARRIER state
95    ip netns exec "${PEER_NS}" ip link set veth1 down
96}
97
98cleanup_v4() {
99    ip neigh flush dev veth0
100    ip link del veth0
101    local -r ns="$(ip netns list|grep $PEER_NS)"
102    [ -n "$ns" ] && ip netns del $ns 2>/dev/null
103
104    sysctl -w net.ipv4.conf.veth0.arp_evict_nocarrier=1 >/dev/null 2>&1
105    sysctl -w net.ipv4.conf.all.arp_evict_nocarrier=1 >/dev/null 2>&1
106}
107
108# Run test when arp_evict_nocarrier = 1 (default).
109run_arp_evict_nocarrier_enabled() {
110    echo "run arp_evict_nocarrier=1 test"
111    setup_v4 "net.ipv4.conf.veth0.arp_evict_nocarrier=1"
112
113    # ARP table should be empty
114    ip neigh get $V4_ADDR1 dev veth0 >/dev/null 2>&1
115
116    if [ $? -eq 0 ];then
117        echo "failed"
118    else
119        echo "ok"
120    fi
121
122    cleanup_v4
123}
124
125# Run test when arp_evict_nocarrier = 0
126run_arp_evict_nocarrier_disabled() {
127    echo "run arp_evict_nocarrier=0 test"
128    setup_v4 "net.ipv4.conf.veth0.arp_evict_nocarrier=0"
129
130    # ARP table should still contain the entry
131    ip neigh get $V4_ADDR1 dev veth0 >/dev/null 2>&1
132
133    if [ $? -eq 0 ];then
134        echo "ok"
135    else
136        echo "failed"
137    fi
138
139    cleanup_v4
140}
141
142run_arp_evict_nocarrier_disabled_all() {
143    echo "run all.arp_evict_nocarrier=0 test"
144    setup_v4 "net.ipv4.conf.all.arp_evict_nocarrier=0"
145
146    # ARP table should still contain the entry
147    ip neigh get $V4_ADDR1 dev veth0 >/dev/null 2>&1
148
149    if [ $? -eq 0 ];then
150        echo "ok"
151    else
152        echo "failed"
153    fi
154
155    cleanup_v4
156}
157
158run_ndisc_evict_nocarrier_enabled() {
159    echo "run ndisc_evict_nocarrier=1 test"
160
161    setup_v6 "net.ipv6.conf.veth1.ndisc_evict_nocarrier=1"
162
163    ip netns exec me ip -6 neigh get $V6_ADDR1 dev veth1 >/dev/null 2>&1
164
165    if [ $? -eq 0 ];then
166        echo "failed"
167    else
168        echo "ok"
169    fi
170
171    cleanup_v6
172}
173
174run_ndisc_evict_nocarrier_disabled() {
175    echo "run ndisc_evict_nocarrier=0 test"
176
177    setup_v6 "net.ipv6.conf.veth1.ndisc_evict_nocarrier=0"
178
179    ip netns exec me ip -6 neigh get $V6_ADDR1 dev veth1 >/dev/null 2>&1
180
181    if [ $? -eq 0 ];then
182        echo "ok"
183    else
184        echo "failed"
185    fi
186
187    cleanup_v6
188}
189
190run_ndisc_evict_nocarrier_disabled_all() {
191    echo "run all.ndisc_evict_nocarrier=0 test"
192
193    setup_v6 "net.ipv6.conf.all.ndisc_evict_nocarrier=0"
194
195    ip netns exec me ip -6 neigh get $V6_ADDR1 dev veth1 >/dev/null 2>&1
196
197    if [ $? -eq 0 ];then
198        echo "ok"
199    else
200        echo "failed"
201    fi
202
203    cleanup_v6
204}
205
206run_all_tests() {
207    run_arp_evict_nocarrier_enabled
208    run_arp_evict_nocarrier_disabled
209    run_arp_evict_nocarrier_disabled_all
210    run_ndisc_evict_nocarrier_enabled
211    run_ndisc_evict_nocarrier_disabled
212    run_ndisc_evict_nocarrier_disabled_all
213}
214
215if [ "$(id -u)" -ne 0 ];then
216	echo "SKIP: Need root privileges"
217	exit $ksft_skip;
218fi
219
220run_all_tests
221