blob: 46813605f837b2d2d09ce04ecf7d32438ba6c7db (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
|
#!/bin/sh -e
action="$1"
oldversion="$2"
. /usr/share/debconf/confmodule
db_version 2.0
umask 022
if [ "$action" != configure ]
then
exit 0
fi
check_idea_key() {
#check for old host_key files using IDEA, which openssh does not support
if [ -f /etc/ssh/ssh_host_key ] ; then
if ssh-keygen -p -N '' -f /etc/ssh/ssh_host_key 2>&1 | \
grep -q 'unknown cipher' 2>/dev/null ; then
mv /etc/ssh/ssh_host_key /etc/ssh/ssh_host_key.old
mv /etc/ssh/ssh_host_key.pub /etc/ssh/ssh_host_key.pub.old
fi
fi
}
get_config_option() {
option="$1"
[ -f /etc/ssh/sshd_config ] || return
# TODO: actually only one '=' allowed after option
perl -ne 'print if s/^[[:space:]]*'"$option"'[[:space:]=]+//i' \
/etc/ssh/sshd_config
}
set_config_option() {
option="$1"
value="$2"
perl -e '
$option = $ARGV[0]; $value = $ARGV[1]; $done = 0;
while (<STDIN>) {
if (s/^\s*\Q$option\E\s+.*/$option $value/) {
$done = 1;
}
print;
}
print "\n$option $value\n" unless $done;' \
"$option" "$value" \
< /etc/ssh/sshd_config > /etc/ssh/sshd_config.dpkg-new
chown --reference /etc/ssh/sshd_config /etc/ssh/sshd_config.dpkg-new
chmod --reference /etc/ssh/sshd_config /etc/ssh/sshd_config.dpkg-new
mv /etc/ssh/sshd_config.dpkg-new /etc/ssh/sshd_config
}
host_keys_required() {
hostkeys="$(get_config_option HostKey)"
if [ "$hostkeys" ]; then
echo "$hostkeys"
else
# No HostKey directives at all, so the server picks some
# defaults depending on the setting of Protocol.
protocol="$(get_config_option Protocol)"
[ "$protocol" ] || protocol=1,2
if echo "$protocol" | grep 1 >/dev/null; then
echo /etc/ssh/ssh_host_key
fi
if echo "$protocol" | grep 2 >/dev/null; then
echo /etc/ssh/ssh_host_rsa_key
echo /etc/ssh/ssh_host_dsa_key
fi
fi
}
create_key() {
msg="$1"
shift
hostkeys="$1"
shift
file="$1"
shift
if echo "$hostkeys" | grep -x "$file" >/dev/null && \
[ ! -f "$file" ] ; then
echo -n $msg
ssh-keygen -q -f "$file" -N '' "$@"
echo
fi
}
create_keys() {
hostkeys="$(host_keys_required)"
create_key "Creating SSH1 key; this may take some time ..." \
"$hostkeys" /etc/ssh/ssh_host_key -t rsa1
create_key "Creating SSH2 RSA key; this may take some time ..." \
"$hostkeys" /etc/ssh/ssh_host_rsa_key -t rsa
create_key "Creating SSH2 DSA key; this may take some time ..." \
"$hostkeys" /etc/ssh/ssh_host_dsa_key -t dsa
}
check_password_auth() {
passwordauth="$(get_config_option PasswordAuthentication)"
crauth="$(get_config_option ChallengeResponseAuthentication)"
if [ "$passwordauth" = no ] && \
([ -z "$crauth" ] || [ "$crauth" = yes ]); then
db_get ssh/disable_cr_auth
if [ "$RET" = true ]; then
set_config_option ChallengeResponseAuthentication no
fi
fi
}
create_sshdconfig() {
if [ -e /etc/ssh/sshd_config ] ; then
if dpkg --compare-versions "$oldversion" lt-nl 1:1.3 ; then
db_get ssh/new_config
if [ "$RET" = "false" ] ; then return 0; fi
else
# Upgrade sshd configuration from a sane version.
if (dpkg --compare-versions "$oldversion" lt-nl 1:3.8p1-1 && \
! grep -iq ^UsePAM /etc/ssh/sshd_config) || \
grep -Eiq '^(PAMAuthenticationViaKbdInt|RhostsAuthentication)' \
/etc/ssh/sshd_config ; then
# Upgrade from pre-3.7: UsePAM needed to maintain standard
# Debian configuration.
# Note that --compare-versions is sadly not reliable enough
# here due to the package split of ssh into openssh-client
# and openssh-server. The extra grep for some deprecated
# options should with any luck be a good enough heuristic.
echo -n 'Upgrading sshd_config (old version in .dpkg-old) ...'
cp -a /etc/ssh/sshd_config /etc/ssh/sshd_config.dpkg-old
perl -pe 's/^(PAMAuthenticationViaKbdInt|RhostsAuthentication)\b/#$1/i' \
/etc/ssh/sshd_config > /etc/ssh/sshd_config.dpkg-new
echo >> /etc/ssh/sshd_config.dpkg-new
echo 'UsePAM yes' >> /etc/ssh/sshd_config.dpkg-new
chown --reference /etc/ssh/sshd_config \
/etc/ssh/sshd_config.dpkg-new
chmod --reference /etc/ssh/sshd_config \
/etc/ssh/sshd_config.dpkg-new
mv /etc/ssh/sshd_config.dpkg-new /etc/ssh/sshd_config
echo
fi
# An empty version means we're upgrading from before the
# package split, so check.
if dpkg --compare-versions "$oldversion" lt 1:3.8.1p1-11; then
check_password_auth
fi
return 0
fi
fi
#Preserve old sshd_config before generating a new one
if [ -e /etc/ssh/sshd_config ] ; then
mv /etc/ssh/sshd_config /etc/ssh/sshd_config.dpkg-old
fi
cat <<EOF > /etc/ssh/sshd_config
# Package generated configuration file
# See the sshd(8) manpage for details
# What ports, IPs and protocols we listen for
Port 22
# Use these options to restrict which interfaces/protocols sshd will bind to
#ListenAddress ::
#ListenAddress 0.0.0.0
EOF
db_get ssh/protocol2_only
if [ "$RET" = "false" ]; then
cat <<EOF >> /etc/ssh/sshd_config
Protocol 2,1
# HostKeys for protocol version 1
HostKey /etc/ssh/ssh_host_key
# HostKeys for protocol version 2
HostKey /etc/ssh/ssh_host_rsa_key
HostKey /etc/ssh/ssh_host_dsa_key
EOF
else
cat <<EOF >> /etc/ssh/sshd_config
Protocol 2
# HostKeys for protocol version 2
HostKey /etc/ssh/ssh_host_rsa_key
HostKey /etc/ssh/ssh_host_dsa_key
EOF
fi
cat <<EOF >> /etc/ssh/sshd_config
#Privilege Separation is turned on for security
UsePrivilegeSeparation yes
# Lifetime and size of ephemeral version 1 server key
KeyRegenerationInterval 3600
ServerKeyBits 768
# Logging
SyslogFacility AUTH
LogLevel INFO
# Authentication:
LoginGraceTime 120
PermitRootLogin yes
StrictModes yes
RSAAuthentication yes
PubkeyAuthentication yes
#AuthorizedKeysFile %h/.ssh/authorized_keys
# Don't read the user's ~/.rhosts and ~/.shosts files
IgnoreRhosts yes
# For this to work you will also need host keys in /etc/ssh_known_hosts
RhostsRSAAuthentication no
# similar for protocol version 2
HostbasedAuthentication no
# Uncomment if you don't trust ~/.ssh/known_hosts for RhostsRSAAuthentication
#IgnoreUserKnownHosts yes
# To enable empty passwords, change to yes (NOT RECOMMENDED)
PermitEmptyPasswords no
# Change to yes to enable challenge-response passwords (beware issues with
# some PAM modules and threads)
ChallengeResponseAuthentication no
# Change to no to disable tunnelled clear text passwords
#PasswordAuthentication yes
# To change Kerberos options
#KerberosAuthentication no
#KerberosOrLocalPasswd yes
#AFSTokenPassing no
#KerberosTicketCleanup no
# Kerberos TGT Passing does only work with the AFS kaserver
#KerberosTgtPassing yes
X11Forwarding no
X11DisplayOffset 10
PrintMotd no
PrintLastLog yes
KeepAlive yes
#UseLogin no
#MaxStartups 10:30:60
#Banner /etc/issue.net
# Allow client to pass locale environment variables
AcceptEnv LANG LC_*
Subsystem sftp /usr/lib/sftp-server
UsePAM yes
EOF
}
fix_statoverride() {
# Remove an erronous override for sshd (we should have overridden ssh)
if [ -x /usr/sbin/dpkg-statoverride ]; then
if dpkg-statoverride --list /usr/sbin/sshd >/dev/null ; then
dpkg-statoverride --remove /usr/sbin/sshd
fi
fi
}
setup_sshd_user() {
if ! getent passwd sshd >/dev/null; then
adduser --quiet --system --no-create-home --home /var/run/sshd sshd
fi
}
fix_conffile_permissions() {
# Clean up after executable /etc/default/ssh in 1:3.5p1-5. dpkg
# doesn't do this for us; see bug #192981.
chmod 644 /etc/default/ssh
}
setup_init() {
if [ -x /etc/init.d/ssh ]; then
update-rc.d ssh defaults >/dev/null
if [ -x /usr/sbin/invoke-rc.d ]; then
invoke-rc.d ssh restart
else
/etc/init.d/ssh restart
fi
fi
}
create_sshdconfig
check_idea_key
create_keys
fix_statoverride
setup_sshd_user
if dpkg --compare-versions "$2" lt 1:3.6.1p2-2; then
fix_conffile_permissions
fi
setup_init
db_stop
exit 0
|