Пакет OpenVPN

• OpenVPN HOWTO

# apt install openvpn

Установка openvpn на CentOS 7

• Создание параметра DH
• Создание центра сертификации
• Создание сертификата сервиса, подписанного CA

# cp ca.* /etc/ssl/certs/
# cp gate.crt /etc/ssl/certs/
# cp gate.key /etc/ssl/private/

gate# cat /etc/openvpn/openvpn1.conf

dev tun
# port 1194
# proto udp
keepalive 10 120
server 192.168.200+X.0 255.255.255.0
push "route 192.168.100+X.0 255.255.255.0"

#push "route 192.168.X.0 255.255.255.0"
#push "dhcp-option DNS 192.168.X.10"
#push "block-outside-dns"
#push "dhcp-option DOMAIN corpX.un"

dh /etc/openvpn/dh2048.pem

ca /etc/ssl/certs/ca.crt
crl-verify /etc/ssl/certs/ca.crl
cert /etc/ssl/certs/gate.crt
key /etc/ssl/private/gate.key

status /var/log/openvpn1-status.log

# openvpn --config /etc/openvpn/openvpn1.conf

# timeout 5 openvpn --port 65500 --config /etc/openvpn/openvpn1.conf; test $? -eq 124 && echo OK

# systemctl enable openvpn@openvpn1

# systemctl start openvpn@openvpn1

• https://mail.bmstu.ru/~postmaster/openvpn-install-2.4.0-I601.exe
• OpenVPN community downloads
• Начиная с Windows 7 необходимо запускать OpenVPN с правами администратора
• Создание пользовательского сертификата, подписанного CA

Start OpenVPN GUI

C:\>notepad C:\Users\student\OpenVPN\config\user1.ovpn

dev tun
# port 1194
# proto udp
client
remote 172.16.1.X
ca ca.crt
cert user1.crt
key user1.key

debian:~# apt install openvpn resolvconf wget

debian:~# openvpn --script-security 2 --up /etc/openvpn/update-resolv-conf --down /etc/openvpn/update-resolv-conf --config user1.ovpn

• OpenVPN routing from server to client

• базируется на атрибуте CN

gate# cat /etc/openvpn/openvpn1.conf

...
client-config-dir ccd
#route 192.168.100+Y.0 255.255.255.0
...

gate# cat /etc/openvpn/ccd/userN

ifconfig-push 192.168.200+X.4*N+2 192.168.200+X.4*N+1
#iroute 192.168.100+Y.0 255.255.255.0

• Setup PAM authentication with OpenVPN's auth-pam module
• openvpn/src/plugins/auth-pam/
• OpenVPN Using alternative authentication methods

• Создание самоподписанного сертификата

gate# less /etc/pam.d/login

gate# cat /etc/openvpn/openvpn1.conf

...
#### crl-verify ...

ca /etc/ssl/certs/server.crt
cert /etc/ssl/certs/server.crt
...
plugin /usr/lib/x86_64-linux-gnu/openvpn/plugins/openvpn-plugin-auth-pam.so login
verify-client-cert none
username-as-common-name
#duplicate-cn  #несколько подключений под одной учетной записью

cmd run as admin C:\>notepad C:\Program Files\OpenVPN\config\client.ovpn

...
auth-user-pass
<ca>
-----BEGIN CERTIFICATE-----
...
-----END CERTIFICATE-----
</ca>

• Freeradius + openvpn

• В новых версиях (с Debian12) теперь так: OpenVPN/fingerprint-authentication

gate.corpX.un# cd /etc/openvpn/

gate.corpX.un# openvpn --genkey --secret static.key

gate.corpX.un# scp static.key gate.corpY.un:/etc/openvpn/

gate.corpX.un# cat connect_to_Y.conf

dev tun
remote 172.16.1.Y
port 1195
# proto udp
keepalive 10 120
ifconfig 192.168.X+Y.X 192.168.X+Y.Y
route 192.168.100+Y.0 255.255.255.0
secret /etc/openvpn/static.key

# cd /usr/local/etc/rc.d/
# ln -s openvpn connect_to_Y

# cat /etc/rc.conf

...
connect_to_Y_enable=yes

gate# cat /var/log/openvpn1-status.log

gate# tail -f /var/log/syslog

gate# cat /etc/openvpn/openvpn1.conf

...
management localhost 7505
# management 0.0.0.0 7505
...

gate# telnet localhost 7505

status

kill user1