-
-
Notifications
You must be signed in to change notification settings - Fork 346
/
openvpn-install.sh
1569 lines (1466 loc) · 43 KB
/
openvpn-install.sh
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
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
#!/bin/bash
#
# https://github.com/hwdsl2/openvpn-install
#
# Based on the work of Nyr and contributors at:
# https://github.com/Nyr/openvpn-install
#
# Copyright (c) 2022-2024 Lin Song <linsongui@gmail.com>
# Copyright (c) 2013-2023 Nyr
#
# Released under the MIT License, see the accompanying file LICENSE.txt
# or https://opensource.org/licenses/MIT
exiterr() { echo "Error: $1" >&2; exit 1; }
exiterr2() { exiterr "'apt-get install' failed."; }
exiterr3() { exiterr "'yum install' failed."; }
exiterr4() { exiterr "'zypper install' failed."; }
check_ip() {
IP_REGEX='^(([0-9]|[1-9][0-9]|1[0-9]{2}|2[0-4][0-9]|25[0-5])\.){3}([0-9]|[1-9][0-9]|1[0-9]{2}|2[0-4][0-9]|25[0-5])$'
printf '%s' "$1" | tr -d '\n' | grep -Eq "$IP_REGEX"
}
check_pvt_ip() {
IPP_REGEX='^(10|127|172\.(1[6-9]|2[0-9]|3[0-1])|192\.168|169\.254)\.'
printf '%s' "$1" | tr -d '\n' | grep -Eq "$IPP_REGEX"
}
check_dns_name() {
FQDN_REGEX='^([a-zA-Z0-9]([a-zA-Z0-9-]{0,61}[a-zA-Z0-9])?\.)+[a-zA-Z]{2,}$'
printf '%s' "$1" | tr -d '\n' | grep -Eq "$FQDN_REGEX"
}
check_root() {
if [ "$(id -u)" != 0 ]; then
exiterr "This installer must be run as root. Try 'sudo bash $0'"
fi
}
check_shell() {
# Detect Debian users running the script with "sh" instead of bash
if readlink /proc/$$/exe | grep -q "dash"; then
exiterr 'This installer needs to be run with "bash", not "sh".'
fi
}
check_kernel() {
# Detect OpenVZ 6
if [[ $(uname -r | cut -d "." -f 1) -eq 2 ]]; then
exiterr "The system is running an old kernel, which is incompatible with this installer."
fi
}
check_os() {
if grep -qs "ubuntu" /etc/os-release; then
os="ubuntu"
os_version=$(grep 'VERSION_ID' /etc/os-release | cut -d '"' -f 2 | tr -d '.')
group_name="nogroup"
elif [[ -e /etc/debian_version ]]; then
os="debian"
os_version=$(grep -oE '[0-9]+' /etc/debian_version | head -1)
group_name="nogroup"
elif [[ -e /etc/almalinux-release || -e /etc/rocky-release || -e /etc/centos-release ]]; then
os="centos"
os_version=$(grep -shoE '[0-9]+' /etc/almalinux-release /etc/rocky-release /etc/centos-release | head -1)
group_name="nobody"
elif grep -qs "Amazon Linux release 2 " /etc/system-release; then
os="centos"
os_version="7"
group_name="nobody"
elif grep -qs "Amazon Linux release 2023" /etc/system-release; then
exiterr "Amazon Linux 2023 is not supported."
elif [[ -e /etc/fedora-release ]]; then
os="fedora"
os_version=$(grep -oE '[0-9]+' /etc/fedora-release | head -1)
group_name="nobody"
elif [[ -e /etc/SUSE-brand && "$(head -1 /etc/SUSE-brand)" == "openSUSE" ]]; then
os="openSUSE"
os_version=$(tail -1 /etc/SUSE-brand | grep -oE '[0-9\\.]+')
group_name="nogroup"
else
exiterr "This installer seems to be running on an unsupported distribution.
Supported distros are Ubuntu, Debian, AlmaLinux, Rocky Linux, CentOS, Fedora, openSUSE and Amazon Linux 2."
fi
}
check_os_ver() {
if [[ "$os" == "ubuntu" && "$os_version" -lt 2004 ]]; then
exiterr "Ubuntu 20.04 or higher is required to use this installer.
This version of Ubuntu is too old and unsupported."
fi
if [[ "$os" == "debian" && "$os_version" -lt 10 ]]; then
exiterr "Debian 10 or higher is required to use this installer.
This version of Debian is too old and unsupported."
fi
if [[ "$os" == "centos" && "$os_version" -lt 8 ]]; then
if ! grep -qs "Amazon Linux release 2 " /etc/system-release; then
exiterr "CentOS 8 or higher is required to use this installer.
This version of CentOS is too old and unsupported."
fi
fi
}
check_tun() {
if [[ ! -e /dev/net/tun ]] || ! ( exec 7<>/dev/net/tun ) 2>/dev/null; then
exiterr "The system does not have the TUN device available.
TUN needs to be enabled before running this installer."
fi
}
set_client_name() {
# Allow a limited set of characters to avoid conflicts
client=$(sed 's/[^0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ_-]/_/g' <<< "$unsanitized_client")
}
parse_args() {
while [ "$#" -gt 0 ]; do
case $1 in
--auto)
auto=1
shift
;;
--addclient)
add_client=1
unsanitized_client="$2"
shift
shift
;;
--exportclient)
export_client=1
unsanitized_client="$2"
shift
shift
;;
--listclients)
list_clients=1
shift
;;
--revokeclient)
revoke_client=1
unsanitized_client="$2"
shift
shift
;;
--uninstall)
remove_ovpn=1
shift
;;
--listenaddr)
listen_addr="$2"
shift
shift
;;
--serveraddr)
server_addr="$2"
shift
shift
;;
--proto)
server_proto="$2"
shift
shift
;;
--port)
server_port="$2"
shift
shift
;;
--clientname)
first_client_name="$2"
shift
shift
;;
--dns1)
dns1="$2"
shift
shift
;;
--dns2)
dns2="$2"
shift
shift
;;
-y|--yes)
assume_yes=1
shift
;;
-h|--help)
show_usage
;;
*)
show_usage "Unknown parameter: $1"
;;
esac
done
}
check_args() {
if [ "$auto" != 0 ] && [ -e "$OVPN_CONF" ]; then
show_usage "Invalid parameter '--auto'. OpenVPN is already set up on this server."
fi
if [ "$((add_client + export_client + list_clients + revoke_client))" -gt 1 ]; then
show_usage "Invalid parameters. Specify only one of '--addclient', '--exportclient', '--listclients' or '--revokeclient'."
fi
if [ "$remove_ovpn" = 1 ]; then
if [ "$((add_client + export_client + list_clients + revoke_client + auto))" -gt 0 ]; then
show_usage "Invalid parameters. '--uninstall' cannot be specified with other parameters."
fi
fi
if [ ! -e "$OVPN_CONF" ]; then
st_text="You must first set up OpenVPN before"
[ "$add_client" = 1 ] && exiterr "$st_text adding a client."
[ "$export_client" = 1 ] && exiterr "$st_text exporting a client."
[ "$list_clients" = 1 ] && exiterr "$st_text listing clients."
[ "$revoke_client" = 1 ] && exiterr "$st_text revoking a client."
[ "$remove_ovpn" = 1 ] && exiterr "Cannot remove OpenVPN because it has not been set up on this server."
fi
if [ "$((add_client + export_client + revoke_client))" = 1 ] && [ -n "$first_client_name" ]; then
show_usage "Invalid parameters. '--clientname' can only be specified when installing OpenVPN."
fi
if [ -n "$listen_addr" ] || [ -n "$server_addr" ] || [ -n "$server_proto" ] \
|| [ -n "$server_port" ] || [ -n "$first_client_name" ] || [ -n "$dns1" ]; then
if [ -e "$OVPN_CONF" ]; then
show_usage "Invalid parameters. OpenVPN is already set up on this server."
elif [ "$auto" = 0 ]; then
show_usage "Invalid parameters. You must specify '--auto' when using these parameters."
fi
fi
if [ "$add_client" = 1 ]; then
set_client_name
if [ -z "$client" ]; then
exiterr "Invalid client name. Use one word only, no special characters except '-' and '_'."
elif [ -e /etc/openvpn/server/easy-rsa/pki/issued/"$client".crt ]; then
exiterr "$client: invalid name. Client already exists."
fi
fi
if [ "$export_client" = 1 ] || [ "$revoke_client" = 1 ]; then
set_client_name
if [ -z "$client" ] || [ ! -e /etc/openvpn/server/easy-rsa/pki/issued/"$client".crt ]; then
exiterr "Invalid client name, or client does not exist."
fi
fi
if [ -n "$listen_addr" ] && ! check_ip "$listen_addr"; then
show_usage "Invalid listen address. Must be an IPv4 address."
fi
if [ -n "$listen_addr" ] && [ -z "$server_addr" ]; then
show_usage "You must also specify the server address if the listen address is specified."
fi
if [ -n "$server_addr" ] && { ! check_dns_name "$server_addr" && ! check_ip "$server_addr"; }; then
exiterr "Invalid server address. Must be a fully qualified domain name (FQDN) or an IPv4 address."
fi
if [ -n "$first_client_name" ]; then
unsanitized_client="$first_client_name"
set_client_name
if [ -z "$client" ]; then
exiterr "Invalid client name. Use one word only, no special characters except '-' and '_'."
fi
fi
if [ -n "$server_proto" ]; then
case "$server_proto" in
[tT][cC][pP])
server_proto=tcp
;;
[uU][dD][pP])
server_proto=udp
;;
*)
exiterr "Invalid protocol. Must be TCP or UDP."
;;
esac
fi
if [ -n "$server_port" ]; then
if [[ ! "$server_port" =~ ^[0-9]+$ || "$server_port" -gt 65535 ]]; then
exiterr "Invalid port. Must be an integer between 1 and 65535."
fi
fi
if { [ -n "$dns1" ] && ! check_ip "$dns1"; } \
|| { [ -n "$dns2" ] && ! check_ip "$dns2"; }; then
exiterr "Invalid DNS server(s)."
fi
if [ -z "$dns1" ] && [ -n "$dns2" ]; then
show_usage "Invalid DNS server. --dns2 cannot be specified without --dns1."
fi
if [ -n "$dns1" ]; then
dns=7
else
dns=2
fi
}
check_nftables() {
if [ "$os" = "centos" ]; then
if grep -qs "hwdsl2 VPN script" /etc/sysconfig/nftables.conf \
|| systemctl is-active --quiet nftables 2>/dev/null; then
exiterr "This system has nftables enabled, which is not supported by this installer."
fi
fi
}
install_wget() {
# Detect some Debian minimal setups where neither wget nor curl are installed
if ! hash wget 2>/dev/null && ! hash curl 2>/dev/null; then
if [ "$auto" = 0 ]; then
echo "Wget is required to use this installer."
read -n1 -r -p "Press any key to install Wget and continue..."
fi
export DEBIAN_FRONTEND=noninteractive
(
set -x
apt-get -yqq update || apt-get -yqq update
apt-get -yqq install wget >/dev/null
) || exiterr2
fi
}
install_iproute() {
if ! hash ip 2>/dev/null; then
if [ "$auto" = 0 ]; then
echo "iproute is required to use this installer."
read -n1 -r -p "Press any key to install iproute and continue..."
fi
if [ "$os" = "debian" ] || [ "$os" = "ubuntu" ]; then
export DEBIAN_FRONTEND=noninteractive
(
set -x
apt-get -yqq update || apt-get -yqq update
apt-get -yqq install iproute2 >/dev/null
) || exiterr2
elif [ "$os" = "openSUSE" ]; then
(
set -x
zypper install iproute2 >/dev/null
) || exiterr4
else
(
set -x
yum -y -q install iproute >/dev/null
) || exiterr3
fi
fi
}
show_header() {
cat <<'EOF'
OpenVPN Script
https://github.com/hwdsl2/openvpn-install
EOF
}
show_header2() {
cat <<'EOF'
Welcome to this OpenVPN server installer!
GitHub: https://github.com/hwdsl2/openvpn-install
EOF
}
show_header3() {
cat <<'EOF'
Copyright (c) 2022-2024 Lin Song
Copyright (c) 2013-2023 Nyr
EOF
}
show_usage() {
if [ -n "$1" ]; then
echo "Error: $1" >&2
fi
show_header
show_header3
cat 1>&2 <<EOF
Usage: bash $0 [options]
Options:
--addclient [client name] add a new client
--exportclient [client name] export configuration for an existing client
--listclients list the names of existing clients
--revokeclient [client name] revoke an existing client
--uninstall remove OpenVPN and delete all configuration
-y, --yes assume "yes" as answer to prompts when revoking a client or removing OpenVPN
-h, --help show this help message and exit
Install options (optional):
--auto auto install OpenVPN using default or custom options
--listenaddr [IPv4 address] IPv4 address that OpenVPN should listen on for requests
--serveraddr [DNS name or IP] server address, must be a fully qualified domain name (FQDN) or an IPv4 address
--proto [TCP or UDP] protocol for OpenVPN (TCP or UDP, default: UDP)
--port [number] port for OpenVPN (1-65535, default: 1194)
--clientname [client name] name for the first OpenVPN client (default: client)
--dns1 [DNS server IP] primary DNS server for clients (default: Google Public DNS)
--dns2 [DNS server IP] secondary DNS server for clients
To customize options, you may also run this script without arguments.
EOF
exit 1
}
show_welcome() {
if [ "$auto" = 0 ]; then
show_header2
echo 'I need to ask you a few questions before starting setup.'
echo 'You can use the default options and just press enter if you are OK with them.'
else
show_header
op_text=default
if [ -n "$listen_addr" ] || [ -n "$server_addr" ] || [ -n "$server_proto" ] \
|| [ -n "$server_port" ] || [ -n "$first_client_name" ] || [ -n "$dns1" ]; then
op_text=custom
fi
echo
echo "Starting OpenVPN setup using $op_text options."
fi
}
show_dns_name_note() {
cat <<EOF
Note: Make sure this DNS name '$1'
resolves to the IPv4 address of this server.
EOF
}
enter_server_address() {
echo
echo "Do you want OpenVPN clients to connect to this server using a DNS name,"
printf "e.g. vpn.example.com, instead of its IP address? [y/N] "
read -r response
case $response in
[yY][eE][sS]|[yY])
use_dns_name=1
echo
;;
*)
use_dns_name=0
;;
esac
if [ "$use_dns_name" = 1 ]; then
read -rp "Enter the DNS name of this VPN server: " server_addr_i
until check_dns_name "$server_addr_i"; do
echo "Invalid DNS name. You must enter a fully qualified domain name (FQDN)."
read -rp "Enter the DNS name of this VPN server: " server_addr_i
done
detect_ip
public_ip="$server_addr_i"
show_dns_name_note "$public_ip"
else
detect_ip
check_nat_ip
fi
}
find_public_ip() {
ip_url1="http://ipv4.icanhazip.com"
ip_url2="http://ip1.dynupdate.no-ip.com"
# Get public IP and sanitize with grep
get_public_ip=$(grep -m 1 -oE '^[0-9]{1,3}(\.[0-9]{1,3}){3}$' <<< "$(wget -T 10 -t 1 -4qO- "$ip_url1" || curl -m 10 -4Ls "$ip_url1")")
if ! check_ip "$get_public_ip"; then
get_public_ip=$(grep -m 1 -oE '^[0-9]{1,3}(\.[0-9]{1,3}){3}$' <<< "$(wget -T 10 -t 1 -4qO- "$ip_url2" || curl -m 10 -4Ls "$ip_url2")")
fi
}
detect_ip() {
# If system has a single IPv4, it is selected automatically.
if [[ $(ip -4 addr | grep inet | grep -vEc '127(\.[0-9]{1,3}){3}') -eq 1 ]]; then
ip=$(ip -4 addr | grep inet | grep -vE '127(\.[0-9]{1,3}){3}' | cut -d '/' -f 1 | grep -oE '[0-9]{1,3}(\.[0-9]{1,3}){3}')
else
# Use the IP address on the default route
ip=$(ip -4 route get 1 | sed 's/ uid .*//' | awk '{print $NF;exit}' 2>/dev/null)
if ! check_ip "$ip"; then
find_public_ip
ip_match=0
if [ -n "$get_public_ip" ]; then
ip_list=$(ip -4 addr | grep inet | grep -vE '127(\.[0-9]{1,3}){3}' | cut -d '/' -f 1 | grep -oE '[0-9]{1,3}(\.[0-9]{1,3}){3}')
while IFS= read -r line; do
if [ "$line" = "$get_public_ip" ]; then
ip_match=1
ip="$line"
fi
done <<< "$ip_list"
fi
if [ "$ip_match" = 0 ]; then
if [ "$auto" = 0 ]; then
echo
echo "Which IPv4 address should be used?"
num_of_ip=$(ip -4 addr | grep inet | grep -vEc '127(\.[0-9]{1,3}){3}')
ip -4 addr | grep inet | grep -vE '127(\.[0-9]{1,3}){3}' | cut -d '/' -f 1 | grep -oE '[0-9]{1,3}(\.[0-9]{1,3}){3}' | nl -s ') '
read -rp "IPv4 address [1]: " ip_num
until [[ -z "$ip_num" || "$ip_num" =~ ^[0-9]+$ && "$ip_num" -le "$num_of_ip" ]]; do
echo "$ip_num: invalid selection."
read -rp "IPv4 address [1]: " ip_num
done
[[ -z "$ip_num" ]] && ip_num=1
else
ip_num=1
fi
ip=$(ip -4 addr | grep inet | grep -vE '127(\.[0-9]{1,3}){3}' | cut -d '/' -f 1 | grep -oE '[0-9]{1,3}(\.[0-9]{1,3}){3}' | sed -n "$ip_num"p)
fi
fi
fi
if ! check_ip "$ip"; then
echo "Error: Could not detect this server's IP address." >&2
echo "Abort. No changes were made." >&2
exit 1
fi
}
check_nat_ip() {
# If $ip is a private IP address, the server must be behind NAT
if check_pvt_ip "$ip"; then
find_public_ip
if ! check_ip "$get_public_ip"; then
if [ "$auto" = 0 ]; then
echo
echo "This server is behind NAT. What is the public IPv4 address?"
read -rp "Public IPv4 address: " public_ip
until check_ip "$public_ip"; do
echo "Invalid input."
read -rp "Public IPv4 address: " public_ip
done
else
echo "Error: Could not detect this server's public IP." >&2
echo "Abort. No changes were made." >&2
exit 1
fi
else
public_ip="$get_public_ip"
fi
fi
}
show_config() {
if [ "$auto" != 0 ]; then
echo
if [ -n "$listen_addr" ]; then
echo "Listen address: $listen_addr"
fi
if [ -n "$server_addr" ]; then
echo "Server address: $server_addr"
else
printf '%s' "Server IP: "
[ -n "$public_ip" ] && printf '%s\n' "$public_ip" || printf '%s\n' "$ip"
fi
if [ "$server_proto" = "tcp" ]; then
proto_text=TCP
else
proto_text=UDP
fi
[ -n "$server_port" ] && port_text="$server_port" || port_text=1194
[ -n "$first_client_name" ] && client_text="$client" || client_text=client
if [ -n "$dns1" ] && [ -n "$dns2" ]; then
dns_text="$dns1, $dns2"
elif [ -n "$dns1" ]; then
dns_text="$dns1"
else
dns_text="Google Public DNS"
fi
echo "Port: $proto_text/$port_text"
echo "Client name: $client_text"
echo "Client DNS: $dns_text"
fi
}
detect_ipv6() {
ip6=""
if [[ $(ip -6 addr | grep -c 'inet6 [23]') -ne 0 ]]; then
ip6=$(ip -6 addr | grep 'inet6 [23]' | cut -d '/' -f 1 | grep -oE '([0-9a-fA-F]{0,4}:){1,7}[0-9a-fA-F]{0,4}' | sed -n 1p)
fi
}
select_protocol() {
if [ "$auto" = 0 ]; then
echo
echo "Which protocol should OpenVPN use?"
echo " 1) UDP (recommended)"
echo " 2) TCP"
read -rp "Protocol [1]: " protocol
until [[ -z "$protocol" || "$protocol" =~ ^[12]$ ]]; do
echo "$protocol: invalid selection."
read -rp "Protocol [1]: " protocol
done
case "$protocol" in
1|"")
protocol=udp
;;
2)
protocol=tcp
;;
esac
else
[ -n "$server_proto" ] && protocol="$server_proto" || protocol=udp
fi
}
select_port() {
if [ "$auto" = 0 ]; then
echo
echo "Which port should OpenVPN listen to?"
read -rp "Port [1194]: " port
until [[ -z "$port" || "$port" =~ ^[0-9]+$ && "$port" -le 65535 ]]; do
echo "$port: invalid port."
read -rp "Port [1194]: " port
done
[[ -z "$port" ]] && port=1194
else
[ -n "$server_port" ] && port="$server_port" || port=1194
fi
}
enter_custom_dns() {
read -rp "Enter primary DNS server: " dns1
until check_ip "$dns1"; do
echo "Invalid DNS server."
read -rp "Enter primary DNS server: " dns1
done
read -rp "Enter secondary DNS server (Enter to skip): " dns2
until [ -z "$dns2" ] || check_ip "$dns2"; do
echo "Invalid DNS server."
read -rp "Enter secondary DNS server (Enter to skip): " dns2
done
}
select_dns() {
if [ "$auto" = 0 ]; then
echo
echo "Select a DNS server for the clients:"
echo " 1) Current system resolvers"
echo " 2) Google Public DNS"
echo " 3) Cloudflare DNS"
echo " 4) OpenDNS"
echo " 5) Quad9"
echo " 6) AdGuard DNS"
echo " 7) Custom"
read -rp "DNS server [2]: " dns
until [[ -z "$dns" || "$dns" =~ ^[1-7]$ ]]; do
echo "$dns: invalid selection."
read -rp "DNS server [2]: " dns
done
else
dns=2
fi
if [ "$dns" = 7 ]; then
enter_custom_dns
fi
}
enter_first_client_name() {
if [ "$auto" = 0 ]; then
echo
echo "Enter a name for the first client:"
read -rp "Name [client]: " unsanitized_client
set_client_name
[[ -z "$client" ]] && client=client
else
if [ -n "$first_client_name" ]; then
unsanitized_client="$first_client_name"
set_client_name
else
client=client
fi
fi
}
show_setup_ready() {
if [ "$auto" = 0 ]; then
echo
echo "OpenVPN installation is ready to begin."
fi
}
check_firewall() {
# Install a firewall if firewalld or iptables are not already available
if ! systemctl is-active --quiet firewalld.service && ! hash iptables 2>/dev/null; then
if [[ "$os" == "centos" || "$os" == "fedora" ]]; then
firewall="firewalld"
elif [[ "$os" == "openSUSE" ]]; then
firewall="firewalld"
elif [[ "$os" == "debian" || "$os" == "ubuntu" ]]; then
firewall="iptables"
fi
if [[ "$firewall" == "firewalld" ]]; then
# We don't want to silently enable firewalld, so we give a subtle warning
# If the user continues, firewalld will be installed and enabled during setup
echo
echo "Note: firewalld, which is required to manage routing tables, will also be installed."
fi
fi
}
abort_and_exit() {
echo "Abort. No changes were made." >&2
exit 1
}
confirm_setup() {
if [ "$auto" = 0 ]; then
printf "Do you want to continue? [Y/n] "
read -r response
case $response in
[yY][eE][sS]|[yY]|'')
:
;;
*)
abort_and_exit
;;
esac
fi
}
show_start_setup() {
echo
echo "Installing OpenVPN, please wait..."
}
disable_limitnproc() {
# If running inside a container, disable LimitNPROC to prevent conflicts
if systemd-detect-virt -cq; then
mkdir /etc/systemd/system/openvpn-server@server.service.d/ 2>/dev/null
echo "[Service]
LimitNPROC=infinity" > /etc/systemd/system/openvpn-server@server.service.d/disable-limitnproc.conf
fi
}
install_pkgs() {
if [[ "$os" = "debian" || "$os" = "ubuntu" ]]; then
export DEBIAN_FRONTEND=noninteractive
(
set -x
apt-get -yqq update || apt-get -yqq update
apt-get -yqq --no-install-recommends install openvpn >/dev/null
) || exiterr2
(
set -x
apt-get -yqq install openssl ca-certificates $firewall >/dev/null
) || exiterr2
elif [[ "$os" = "centos" ]]; then
if grep -qs "Amazon Linux release 2 " /etc/system-release; then
(
set -x
amazon-linux-extras install epel -y >/dev/null
) || exit 1
else
(
set -x
yum -y -q install epel-release >/dev/null
) || exiterr3
fi
(
set -x
yum -y -q install openvpn openssl ca-certificates tar $firewall >/dev/null 2>&1
) || exiterr3
elif [[ "$os" = "fedora" ]]; then
(
set -x
dnf install -y openvpn openssl ca-certificates tar $firewall >/dev/null
) || exiterr "'dnf install' failed."
else
# Else, OS must be openSUSE
(
set -x
zypper install -y openvpn openssl ca-certificates tar $firewall >/dev/null
) || exiterr4
fi
# If firewalld was just installed, enable it
if [[ "$firewall" == "firewalld" ]]; then
(
set -x
systemctl enable --now firewalld.service >/dev/null 2>&1
)
fi
}
remove_pkgs() {
if [[ "$os" = "debian" || "$os" = "ubuntu" ]]; then
(
set -x
rm -rf /etc/openvpn/server
apt-get remove --purge -y openvpn >/dev/null
)
elif [[ "$os" = "openSUSE" ]]; then
(
set -x
zypper remove -y openvpn >/dev/null
rm -rf /etc/openvpn/server
)
rm -f /etc/openvpn/ipp.txt
else
# Else, OS must be CentOS or Fedora
(
set -x
yum -y -q remove openvpn >/dev/null
rm -rf /etc/openvpn/server
)
fi
}
create_firewall_rules() {
if systemctl is-active --quiet firewalld.service; then
# Using both permanent and not permanent rules to avoid a firewalld
# reload.
# We don't use --add-service=openvpn because that would only work with
# the default port and protocol.
firewall-cmd -q --add-port="$port"/"$protocol"
firewall-cmd -q --zone=trusted --add-source=10.8.0.0/24
firewall-cmd -q --permanent --add-port="$port"/"$protocol"
firewall-cmd -q --permanent --zone=trusted --add-source=10.8.0.0/24
# Set NAT for the VPN subnet
firewall-cmd -q --direct --add-rule ipv4 nat POSTROUTING 0 -s 10.8.0.0/24 ! -d 10.8.0.0/24 -j MASQUERADE
firewall-cmd -q --permanent --direct --add-rule ipv4 nat POSTROUTING 0 -s 10.8.0.0/24 ! -d 10.8.0.0/24 -j MASQUERADE
if [[ -n "$ip6" ]]; then
firewall-cmd -q --zone=trusted --add-source=fddd:1194:1194:1194::/64
firewall-cmd -q --permanent --zone=trusted --add-source=fddd:1194:1194:1194::/64
firewall-cmd -q --direct --add-rule ipv6 nat POSTROUTING 0 -s fddd:1194:1194:1194::/64 ! -d fddd:1194:1194:1194::/64 -j MASQUERADE
firewall-cmd -q --permanent --direct --add-rule ipv6 nat POSTROUTING 0 -s fddd:1194:1194:1194::/64 ! -d fddd:1194:1194:1194::/64 -j MASQUERADE
fi
else
# Create a service to set up persistent iptables rules
iptables_path=$(command -v iptables)
ip6tables_path=$(command -v ip6tables)
# nf_tables is not available as standard in OVZ kernels. So use iptables-legacy
# if we are in OVZ, with a nf_tables backend and iptables-legacy is available.
if [[ $(systemd-detect-virt) == "openvz" ]] && readlink -f "$(command -v iptables)" | grep -q "nft" && hash iptables-legacy 2>/dev/null; then
iptables_path=$(command -v iptables-legacy)
ip6tables_path=$(command -v ip6tables-legacy)
fi
echo "[Unit]
Before=network.target
[Service]
Type=oneshot
ExecStart=$iptables_path -t nat -A POSTROUTING -s 10.8.0.0/24 ! -d 10.8.0.0/24 -j MASQUERADE
ExecStart=$iptables_path -I INPUT -p $protocol --dport $port -j ACCEPT
ExecStart=$iptables_path -I FORWARD -s 10.8.0.0/24 -j ACCEPT
ExecStart=$iptables_path -I FORWARD -m state --state RELATED,ESTABLISHED -j ACCEPT
ExecStop=$iptables_path -t nat -D POSTROUTING -s 10.8.0.0/24 ! -d 10.8.0.0/24 -j MASQUERADE
ExecStop=$iptables_path -D INPUT -p $protocol --dport $port -j ACCEPT
ExecStop=$iptables_path -D FORWARD -s 10.8.0.0/24 -j ACCEPT
ExecStop=$iptables_path -D FORWARD -m state --state RELATED,ESTABLISHED -j ACCEPT" > /etc/systemd/system/openvpn-iptables.service
if [[ -n "$ip6" ]]; then
echo "ExecStart=$ip6tables_path -t nat -A POSTROUTING -s fddd:1194:1194:1194::/64 ! -d fddd:1194:1194:1194::/64 -j MASQUERADE
ExecStart=$ip6tables_path -I FORWARD -s fddd:1194:1194:1194::/64 -j ACCEPT
ExecStart=$ip6tables_path -I FORWARD -m state --state RELATED,ESTABLISHED -j ACCEPT
ExecStop=$ip6tables_path -t nat -D POSTROUTING -s fddd:1194:1194:1194::/64 ! -d fddd:1194:1194:1194::/64 -j MASQUERADE
ExecStop=$ip6tables_path -D FORWARD -s fddd:1194:1194:1194::/64 -j ACCEPT
ExecStop=$ip6tables_path -D FORWARD -m state --state RELATED,ESTABLISHED -j ACCEPT" >> /etc/systemd/system/openvpn-iptables.service
fi
echo "RemainAfterExit=yes
[Install]
WantedBy=multi-user.target" >> /etc/systemd/system/openvpn-iptables.service
(
set -x
systemctl enable --now openvpn-iptables.service >/dev/null 2>&1
)
fi
}
remove_firewall_rules() {
port=$(grep '^port ' "$OVPN_CONF" | cut -d " " -f 2)
protocol=$(grep '^proto ' "$OVPN_CONF" | cut -d " " -f 2)
if systemctl is-active --quiet firewalld.service; then
ip=$(firewall-cmd --direct --get-rules ipv4 nat POSTROUTING | grep '\-s 10.8.0.0/24 '"'"'!'"'"' -d 10.8.0.0/24' | grep -oE '[^ ]+$')
# Using both permanent and not permanent rules to avoid a firewalld reload.
firewall-cmd -q --remove-port="$port"/"$protocol"
firewall-cmd -q --zone=trusted --remove-source=10.8.0.0/24
firewall-cmd -q --permanent --remove-port="$port"/"$protocol"
firewall-cmd -q --permanent --zone=trusted --remove-source=10.8.0.0/24
firewall-cmd -q --direct --remove-rule ipv4 nat POSTROUTING 0 -s 10.8.0.0/24 ! -d 10.8.0.0/24 -j MASQUERADE
firewall-cmd -q --permanent --direct --remove-rule ipv4 nat POSTROUTING 0 -s 10.8.0.0/24 ! -d 10.8.0.0/24 -j MASQUERADE
if grep -qs "server-ipv6" "$OVPN_CONF"; then
ip6=$(firewall-cmd --direct --get-rules ipv6 nat POSTROUTING | grep '\-s fddd:1194:1194:1194::/64 '"'"'!'"'"' -d fddd:1194:1194:1194::/64' | grep -oE '[^ ]+$')
firewall-cmd -q --zone=trusted --remove-source=fddd:1194:1194:1194::/64
firewall-cmd -q --permanent --zone=trusted --remove-source=fddd:1194:1194:1194::/64
firewall-cmd -q --direct --remove-rule ipv6 nat POSTROUTING 0 -s fddd:1194:1194:1194::/64 ! -d fddd:1194:1194:1194::/64 -j MASQUERADE
firewall-cmd -q --permanent --direct --remove-rule ipv6 nat POSTROUTING 0 -s fddd:1194:1194:1194::/64 ! -d fddd:1194:1194:1194::/64 -j MASQUERADE
fi
else
systemctl disable --now openvpn-iptables.service
rm -f /etc/systemd/system/openvpn-iptables.service
fi
if sestatus 2>/dev/null | grep "Current mode" | grep -q "enforcing" && [[ "$port" != 1194 ]]; then
semanage port -d -t openvpn_port_t -p "$protocol" "$port"
fi
}
install_easyrsa() {
# Get easy-rsa
easy_rsa_url='https://github.com/OpenVPN/easy-rsa/releases/download/v3.2.1/EasyRSA-3.2.1.tgz'
mkdir -p /etc/openvpn/server/easy-rsa/
{ wget -t 3 -T 30 -qO- "$easy_rsa_url" 2>/dev/null || curl -m 30 -sL "$easy_rsa_url" ; } | tar xz -C /etc/openvpn/server/easy-rsa/ --strip-components 1
if [ ! -f /etc/openvpn/server/easy-rsa/easyrsa ]; then
exiterr "Failed to download EasyRSA from $easy_rsa_url."
fi
chown -R root:root /etc/openvpn/server/easy-rsa/
}
create_pki_and_certs() {
cd /etc/openvpn/server/easy-rsa/ || exit 1
(
set -x
# Create the PKI, set up the CA and the server and client certificates
./easyrsa --batch init-pki >/dev/null
./easyrsa --batch build-ca nopass >/dev/null 2>&1
./easyrsa --batch --days=3650 build-server-full server nopass >/dev/null 2>&1
./easyrsa --batch --days=3650 build-client-full "$client" nopass >/dev/null 2>&1
./easyrsa --batch --days=3650 gen-crl >/dev/null 2>&1
)
# Move the stuff we need
cp pki/ca.crt pki/private/ca.key pki/issued/server.crt pki/private/server.key pki/crl.pem /etc/openvpn/server
# CRL is read with each client connection, while OpenVPN is dropped to nobody
chown nobody:"$group_name" /etc/openvpn/server/crl.pem
# Without +x in the directory, OpenVPN can't run a stat() on the CRL file
chmod o+x /etc/openvpn/server/
(
set -x
# Generate key for tls-crypt
openvpn --genkey --secret /etc/openvpn/server/tc.key >/dev/null
)
# Create the DH parameters file using the predefined ffdhe2048 group
echo '-----BEGIN DH PARAMETERS-----
MIIBCAKCAQEA//////////+t+FRYortKmq/cViAnPTzx2LnFg84tNpWp4TZBFGQz
+8yTnc4kmz75fS/jY2MMddj2gbICrsRhetPfHtXV/WVhJDP1H18GbtCFY2VVPe0a
87VXE15/V8k1mE8McODmi3fipona8+/och3xWKE2rec1MKzKT0g6eXq8CrGCsyT7
YdEIqUuyyOP7uWrat2DX9GgdT0Kj3jlN9K5W7edjcrsZCwenyO4KbXCeAvzhzffi
7MA0BM0oNC9hkXL+nOmFg/+OTxIy7vKBg8P+OxtMb61zO7X8vC7CIAXFjvGDfRaD
ssbzSibBsu/6iGtCOGEoXJf//////////wIBAg==
-----END DH PARAMETERS-----' > /etc/openvpn/server/dh.pem
}
create_dns_config() {
case "$dns" in
1)
# Locate the proper resolv.conf
# Needed for systems running systemd-resolved
if grep '^nameserver' "/etc/resolv.conf" | grep -qv '127.0.0.53' ; then
resolv_conf="/etc/resolv.conf"
else
resolv_conf="/run/systemd/resolve/resolv.conf"
fi
# Obtain the resolvers from resolv.conf and use them for OpenVPN
grep -v '^#\|^;' "$resolv_conf" | grep '^nameserver' | grep -v '127.0.0.53' | grep -oE '[0-9]{1,3}(\.[0-9]{1,3}){3}' | while read line; do
echo "push \"dhcp-option DNS $line\"" >> "$OVPN_CONF"
done
;;
2|"")
echo 'push "dhcp-option DNS 8.8.8.8"' >> "$OVPN_CONF"
echo 'push "dhcp-option DNS 8.8.4.4"' >> "$OVPN_CONF"
;;
3)
echo 'push "dhcp-option DNS 1.1.1.1"' >> "$OVPN_CONF"
echo 'push "dhcp-option DNS 1.0.0.1"' >> "$OVPN_CONF"
;;
4)
echo 'push "dhcp-option DNS 208.67.222.222"' >> "$OVPN_CONF"
echo 'push "dhcp-option DNS 208.67.220.220"' >> "$OVPN_CONF"
;;
5)
echo 'push "dhcp-option DNS 9.9.9.9"' >> "$OVPN_CONF"
echo 'push "dhcp-option DNS 149.112.112.112"' >> "$OVPN_CONF"
;;
6)
echo 'push "dhcp-option DNS 94.140.14.14"' >> "$OVPN_CONF"
echo 'push "dhcp-option DNS 94.140.15.15"' >> "$OVPN_CONF"
;;
7)
echo "push \"dhcp-option DNS $dns1\"" >> "$OVPN_CONF"
if [ -n "$dns2" ]; then
echo "push \"dhcp-option DNS $dns2\"" >> "$OVPN_CONF"
fi
;;
esac
}
create_server_config() {
# Generate server.conf
echo "local $ip
port $port
proto $protocol
dev tun
ca ca.crt
cert server.crt
key server.key
dh dh.pem
auth SHA256
tls-crypt tc.key
topology subnet
server 10.8.0.0 255.255.255.0" > "$OVPN_CONF"
# IPv6
if [[ -z "$ip6" ]]; then
echo 'push "block-ipv6"' >> "$OVPN_CONF"
echo 'push "ifconfig-ipv6 fddd:1194:1194:1194::2/64 fddd:1194:1194:1194::1"' >> "$OVPN_CONF"
else
echo 'server-ipv6 fddd:1194:1194:1194::/64' >> "$OVPN_CONF"
fi
echo 'push "redirect-gateway def1 ipv6 bypass-dhcp"' >> "$OVPN_CONF"
echo 'ifconfig-pool-persist ipp.txt' >> "$OVPN_CONF"
create_dns_config