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|
(One intermediate revision by the same user not shown) |
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| OpenVPN is not compatible with IPSec, IKE, PPTP, or L2TP. | | OpenVPN is not compatible with IPSec, IKE, PPTP, or L2TP. |
|
| |
|
| '''[[OpenVPN(ID)|OpenVPN Instructions - Bahasa Indonesia]]'''
| |
|
| |
|
| | [[OpenVPN_smcr_2012|OpenVPN server setup on Slackware 13.37]] - Multi-client with routing (not bridged). (2012) |
|
| |
|
| __TOC__
| | [[OpenVPN_pre-2009|OpenVPN server/client instructions]] (Pre-2009) |
| == Installation ==
| |
|
| |
|
| '''EASY WAY:'''
| |
| Download and install from Slackbuilds.org or sbopkg.
| |
|
| |
|
| or
| |
|
| |
|
| '''HARD WAY:'''
| |
| Install from source.
| |
|
| |
|
| Download source from [http://openvpn.net openvpn.net]
| | [[OpenVPN(ID)|OpenVPN Instructions - Bahasa Indonesia]] (Pre-2009) |
| | |
| Download verison 2.0
| |
| | |
| install Lzo
| |
| <pre>
| |
| tar zxvf lzo-1.08.tar.gz
| |
| cd lzo-1-08.tar.gz
| |
| ./configure --prefix=/usr
| |
| make ; make install-strip
| |
| </pre>
| |
| install OpenVPN
| |
| <pre>
| |
| tar zxvf openvpn-2.0.tar.gz
| |
| cd openvpn-2.0
| |
| ./configure --prefix=/usr \
| |
| --sysconfdir=/etc/openvpn \
| |
| --enable-pthread \
| |
| --enable-iproute2 \
| |
| --with-ssl \
| |
| --with-lzo-header=/usr/include \
| |
| --with-lzo-lib=/usr/lib \
| |
| --with-ifconfig \
| |
| --with-route \
| |
| --with-mem-check=dmalloc
| |
| make ; make install-strip
| |
| </pre>
| |
| | |
| | |
| ==Creating The Certificates==
| |
| | |
| Save all certificates in '''''/etc/openvpn/certs'''''
| |
| <pre>
| |
| This is a small RSA key management package,
| |
| based on the openssl command line tool, that
| |
| can be found in the easy-rsa subdirectory
| |
| of the OpenVPN distribution.
| |
| | |
| These are reference notes. For step
| |
| by step instructions, see the HOWTO:
| |
| | |
| http://openvpn.net/howto.html
| |
| | |
| INSTALL
| |
| | |
| 1. Edit vars.
| |
| 2. Set KEY_CONFIG to point to the openssl.cnf file
| |
| included in this distribution.
| |
| 3. Set KEY_DIR to point to a directory which will
| |
| contain all keys, certificates, etc. This
| |
| directory need not exist, and if it does,
| |
| it will be deleted with rm -rf, so BE
| |
| CAREFUL how you set KEY_DIR.
| |
| 4. (Optional) Edit other fields in vars
| |
| per your site data. You may want to
| |
| increase KEY_SIZE to 2048 if you are
| |
| paranoid and don't mind slower key
| |
| processing, but certainly 1024 is
| |
| fine for testing purposes. KEY_SIZE
| |
| must be compatible across both peers
| |
| participating in a secure SSL/TLS
| |
| connection.
| |
| 5 . vars
| |
| 6. ./clean-all
| |
| 7. As you create certificates, keys, and
| |
| certificate signing requests, understand that
| |
| only .key files should be kept confidential.
| |
| .crt and .csr files can be sent over insecure
| |
| channels such as plaintext email.
| |
| 8. You should never need to copy a .key file
| |
| between computers. Normally each computer
| |
| will have its own certificate/key pair.
| |
| | |
| BUILD YOUR OWN ROOT CERTIFICATE AUTHORITY (CA) CERTIFICATE/KEY
| |
| | |
| 1. ./build-ca
| |
| 2. ca.crt and ca.key will be built in your KEY_DIR
| |
| directory
| |
| | |
| BUILD AN INTERMEDIATE CERTIFICATE AUTHORITY CERTIFICATE/KEY (optional)
| |
| | |
| 1. ./build-inter inter
| |
| 2. inter.crt and inter.key will be built in your KEY_DIR
| |
| directory and signed with your root certificate.
| |
| | |
| BUILD DIFFIE-HELLMAN PARAMETERS (necessary for
| |
| the server end of a SSL/TLS connection).
| |
| | |
| 1. ./build-dh
| |
| | |
| BUILD A CERTIFICATE SIGNING REQUEST (If
| |
| you want to sign your certificate with a root
| |
| certificate controlled by another individual
| |
| or organization, or residing on a different machine).
| |
| | |
| 1. Get ca.crt (the root certificate) from your
| |
| certificate authority. Though this
| |
| transfer can be over an insecure channel, to prevent
| |
| man-in-the-middle attacks you must confirm that
| |
| ca.crt was not tampered with. Large CAs solve this
| |
| problem by hardwiring their root certificates into
| |
| popular web browsers. A simple way to verify a root
| |
| CA is to call the issuer on the telephone and confirm
| |
| that the md5sum or sha1sum signatures on the ca.crt
| |
| files match (such as with the command: "md5sum ca.crt").
| |
| 2. Choose a name for your certificate such as your computer
| |
| name. In our example we will use "mycert".
| |
| 3. ./build-req mycert
| |
| 4. You can ignore most of the fields, but set
| |
| "Common Name" to something unique such as your
| |
| computer's host name. Leave all password
| |
| fields blank, unless you want your private key
| |
| to be protected by password. Using a password
| |
| is not required -- it will make your key more secure
| |
| but also more inconvenient to use, because you will
| |
| need to supply your password anytime the key is used.
| |
| NOTE: if you are using a password, use ./build-req-pass
| |
| instead of ./build-req
| |
| 5. Your key will be written to $KEY_DIR/mycert.key
| |
| 6. Your certificate signing request will be written to
| |
| to $KEY_DIR/mycert.csr
| |
| 7. Email mycert.csr to the individual or organization
| |
| which controls the root certificate. This can be
| |
| done over an insecure channel.
| |
| 8. After the .csr file is signed by the root certificate
| |
| authority, you will receive a file mycert.crt
| |
| (your certificate). Place mycert.crt in your
| |
| KEY_DIR directory.
| |
| 9. The combined files of mycert.crt, mycert.key,
| |
| and ca.crt can now be used to secure one end of
| |
| an SSL/TLS connection.
| |
| | |
| SIGN A CERTIFICATE SIGNING REQUEST
| |
| | |
| 1. ./sign-req mycert
| |
| 2. mycert.crt will be built in your KEY_DIR
| |
| directory using mycert.csr and your root CA
| |
| file as input.
| |
| | |
| BUILD AND SIGN A CERTIFICATE SIGNING REQUEST
| |
| USING A LOCALLY INSTALLED ROOT CERTIFICATE/KEY -- this
| |
| script generates and signs a certificate in one step,
| |
| but it requires that the generated certificate and private
| |
| key files be copied to the destination host over a
| |
| secure channel.
| |
| | |
| 1. ./build-key mycert (no password protection)
| |
| 2. OR ./build-key-pass mycert (with password protection)
| |
| 3. OR ./build-key-pkcs12 mycert (PKCS #12 format)
| |
| 4. OR ./build-key-server mycert (with nsCertType=server)
| |
| 5. mycert.crt and mycert.key will be built in your
| |
| KEY_DIR directory, and mycert.crt will be signed
| |
| by your root CA. If ./build-key-pkcs12 was used a
| |
| mycert.p12 file will also be created including the
| |
| private key, certificate and the ca certificate.
| |
| | |
| IMPORTANT
| |
| | |
| To avoid a possible Man-in-the-Middle attack where an authorized
| |
| client tries to connect to another client by impersonating the
| |
| server, make sure to enforce some kind of server certificate
| |
| verification by clients. There are currently four different ways
| |
| of accomplishing this, listed in the order of preference:
| |
| | |
| (1) Build your server certificates with the build-key-server
| |
| script. This will designate the certificate as a
| |
| server-only certificate by setting nsCertType=server.
| |
| Now add the following line to your client configuration:
| |
| | |
| ns-cert-type server
| |
| | |
| This will block clients from connecting to any
| |
| server which lacks the nsCertType=server designation
| |
| in its certificate, even if the certificate has been
| |
| signed by the CA which is cited in the OpenVPN configuration
| |
| file (--ca directive).
| |
| | |
| (2) Use the --tls-remote directive on the client to
| |
| accept/reject the server connection based on the common
| |
| name of the server certificate.
| |
| | |
| (3) Use a --tls-verify script or plugin to accept/reject the
| |
| server connection based on a custom test of the server
| |
| certificate's embedded X509 subject details.
| |
| IMPORTANT
| |
| | |
| To avoid a possible Man-in-the-Middle attack where an authorized
| |
| client tries to connect to another client by impersonating the
| |
| server, make sure to enforce some kind of server certificate
| |
| verification by clients. There are currently four different ways
| |
| of accomplishing this, listed in the order of preference:
| |
| | |
| (1) Build your server certificates with the build-key-server
| |
| script. This will designate the certificate as a
| |
| server-only certificate by setting nsCertType=server.
| |
| Now add the following line to your client configuration:
| |
| | |
| ns-cert-type server
| |
| | |
| This will block clients from connecting to any
| |
| server which lacks the nsCertType=server designation
| |
| in its certificate, even if the certificate has been
| |
| signed by the CA which is cited in the OpenVPN configuration
| |
| file (--ca directive).
| |
| | |
| (2) Use the --tls-remote directive on the client to
| |
| accept/reject the server connection based on the common
| |
| name of the server certificate.
| |
| | |
| (3) Use a --tls-verify script or plugin to accept/reject the
| |
| server connection based on a custom test of the server
| |
| certificate's embedded X509 subject details.
| |
| | |
| (4) Sign server certificates with one CA and client certificates
| |
| with a different CA. The client config "ca" directive should
| |
| reference the server-signing CA while the server config "ca"
| |
| directive should reference the client-signing CA.
| |
| | |
| NOTES
| |
| | |
| Show certificate fields:
| |
| openssl x509 -in cert.crt -text
| |
| </pre>
| |
| <pre>
| |
| # cd easy-rsa
| |
| # vi vars
| |
| . vars
| |
| ./clean-all
| |
| | |
| ## BUILD YOUR OWN ROOT CERTIFICATE AUTHORITY (CA) CERTIFICATE/KEY
| |
| ./build.ca
| |
| | |
| ## BUILD AN INTERMEDIATE CERTIFICATE AUTHORITY CERTIFICATE/KEY (optional)
| |
| ./build-inter inter
| |
| | |
| ## BUILD DIFFIE-HELLMAN PARAMETERS (necessary for the server end of a SSL/TLS connection).
| |
| ./build.dh
| |
| | |
| ## BUILD A CERTIFICATE SIGNING REQUEST
| |
| ## (If you want to sign your certificate with a root certificate controlled by another individual
| |
| ## or organization, or residing on a different machine)
| |
| | |
| ./build-req mycert
| |
| ## SIGN A CERTIFICATE SIGNING REQUEST
| |
| ./sign-req mycert
| |
| | |
| ## BUILD AND SIGN A CERTIFICATE SIGNING REQUEST USING A LOCALLY INSTALLED ROOT CERTIFICATE/KEY
| |
| ./build-key mycert (no password protection)
| |
| OR
| |
| ./build-key-pass mycert (with password protection)
| |
| OR
| |
| ./build-key-pkcs12 mycert (PKCS #12 format)
| |
| OR
| |
| ./build-key-server mycert (with nsCertType=server)
| |
| </pre>
| |
| | |
| ==Configuring the Server==
| |
| | |
| Edit the server.conf file: '''''vi /etc/openvpn/server.conf'''''
| |
| <pre>
| |
| ## Mode Server
| |
| mode server
| |
| | |
| ## Local Host Name/IP Server
| |
| ;local 127.0.0.1
| |
| | |
| ## Protocol
| |
| ;proto tcp
| |
| proto udp
| |
| | |
| ## Port
| |
| ; port 1194
| |
| | |
| ## Device Interface
| |
| ;dev tap
| |
| dev tun
| |
| | |
| ## TAP-Win32 adapter name
| |
| ;dev-node MyTap
| |
| | |
| ## SSL/TLS
| |
| ## root certificate (ca)
| |
| ## certificate (cert)
| |
| ## private key (key)
| |
| ca /etc/openvpn/certs/ca.crt
| |
| cert /etc/openvpn/certs/server.crt
| |
| key /etc/openvpn/certs/server.key
| |
| | |
| ## Diffie hellman parameters
| |
| dh dh1024.pem
| |
| | |
| ## VPN subnet
| |
| server 10.8.0.0 255.255.255.0
| |
| | |
| ifconfig-pool-persist ipp.txt
| |
| | |
| ##ethernet bridging
| |
| ;server-bridge 10.8.0.4 255.255.255.0 10.8.0.50 10.8.0.100
| |
| | |
| ## dhcpcaveats
| |
| ;push "route 192.168.10.0 255.255.255.0"
| |
| ;push "route 192.168.20.0 255.255.255.0"
| |
| | |
| ;client-config-dir ccd
| |
| | |
| ;route 192.168.40.128 255.255.255.248
| |
| | |
| ;client-config-dir ccd
| |
| | |
| ;route 10.9.0.0 255.255.255.252
| |
| | |
| ;learn-address ./script
| |
| | |
| ## dhcpcaveats
| |
| ;push "redirect-gateway"
| |
| ;push "dhcp-option DNS 10.8.0.1"
| |
| ;push "dhcp-option WINS 10.8.0.1"
| |
| | |
| ##
| |
| ;client-to-client
| |
| | |
| ## same "COMMON NAME" certificate/key
| |
| ;duplicate-cn
| |
| | |
| ## Status Connection
| |
| keepalive 10 120
| |
| | |
| ## tls-auth key
| |
| ;tls-auth ta.key 0
| |
| | |
| ## Cryptographic cipher
| |
| ;cipher BF-CBC # Blowfish (default)
| |
| ;cipher AES-128-CBC # AES
| |
| ;cipher DES-EDE3-CBC # Triple-DES
| |
| | |
| ## Link Compresion
| |
| comp-lzo
| |
| | |
| ## Max Client Connections
| |
| ;max-clients 100
| |
| | |
| ## daemon privileges (non windows saja)
| |
| user nobody
| |
| group nobody
| |
| | |
| persist-key
| |
| persist-tun
| |
| | |
| ## Openvpn Log
| |
| ;log /var/log/openvpn/openvpn.log
| |
| ;log-append /var/log/openvpn/openvpn.log
| |
| | |
| ## Output Log
| |
| status /var/log/openvpn/openvpn-status.log
| |
| | |
| ## Log Verbosity
| |
| ## 0 is silent, except for fatal errors
| |
| ## 4 is reasonable for general usage
| |
| ## 5 and 6 can help to debug connection problems
| |
| ## 9 is extremely verbose
| |
| verb 3
| |
| | |
| ## Repeating Messages
| |
| ;mute 20
| |
| | |
| ## Pid File
| |
| writepid /var/run/openvpn.pid
| |
| </pre>
| |
| | |
| '''Routing'''
| |
| | |
| <pre>
| |
| echo 1 > /proc/sys/net/ipv4/ip_forward
| |
| route add -net 10.0.1.0 netmask 255.255.255.0 gw 10.4.0.2
| |
| </pre>
| |
| | |
| '''Firewall'''
| |
| <pre>
| |
| iptables -A INPUT -p udp -s 1.2.3.4 --dport 1194 -j ACCEPT
| |
| OR
| |
| iptables -A INPUT -p udp --dport 1194 -j ACCEPT
| |
| | |
| ## Tun Device
| |
| iptables -A INPUT -i tun+ -j ACCEPT
| |
| iptables -A FORWARD -i tun+ -j ACCEPT
| |
| | |
| ## Tap Device
| |
| iptables -A INPUT -i tap+ -j ACCEPT
| |
| iptables -A FORWARD -i tap+ -j ACCEPT
| |
| </pre>
| |
| | |
| ==Configuring the Client==
| |
| | |
| Edit the client.conf file: '''''vi /etc/openvpn/client.conf'''''
| |
| <pre>
| |
| ## Config
| |
| client
| |
| | |
| ## Device Interface
| |
| ;dev tap
| |
| dev tun
| |
| | |
| ## Tap adapter name (Win only)
| |
| ;dev-node MyTap
| |
| | |
| ## Conectivity
| |
| ;proto tcp
| |
| proto udp
| |
| | |
| ## Server [hostname/ip] [port]
| |
| remote my-server-1 1194
| |
| ;remote my-server-2 1194
| |
| | |
| ## load-balancing
| |
| ;remote-random
| |
| | |
| ## resolve host name OpenVPN server
| |
| resolv-retry infinite
| |
| | |
| # local port
| |
| nobind
| |
| | |
| ## privileges (non windows saja)
| |
| user nobody
| |
| group nobody
| |
| | |
| ## preserve
| |
| persist-key
| |
| persist-tun
| |
| | |
| ## HTTP proxy
| |
| ;http-proxy-retry
| |
| ;http-proxy [proxy server] [proxy port]
| |
| | |
| ## duplicate packet warnings
| |
| ;mute-replay-warnings
| |
| | |
| ## SSL/TLS parms
| |
| /etc/openvpn/certs/ca ca.crt
| |
| /etc/openvpn/certs/cert client.crt
| |
| /etc/openvpn/certs/key client.key
| |
| | |
| ## nsCertType key
| |
| ;ns-cert-type server
| |
| | |
| ## tls-auth key
| |
| ;tls-auth /etc/openvpn/certs/ta.key 1
| |
| | |
| ## Cryptographic cipher
| |
| ;cipher x
| |
| | |
| ## Link compression
| |
| comp-lzo
| |
| | |
| ## verbosity
| |
| ## 0 is silent, except for fatal errors
| |
| ## 4 is reasonable for general usage
| |
| ## 5 and 6 can help to debug connection problems
| |
| ## 9 is extremely verbose
| |
| verb 3
| |
| | |
| ## repeating messages
| |
| ;mute 20
| |
| </pre>
| |
| '''Routing'''
| |
| <pre>
| |
| route add -net 10.0.0.0 netmask 255.255.255.0 gw 10.4.0.1
| |
| </pre>
| |
| | |
| ==Example==
| |
| | |
| '''Example 1:''' A simple tunnel without security<br>
| |
| '''On May: Server Side'''
| |
| <pre>
| |
| openvpn --remote jun.kg --dev tun1 --ifconfig 10.4.0.1 10.4.0.2 --verb 9
| |
| </pre>
| |
| | |
| '''On Jun: Client Side'''
| |
| <pre>
| |
| openvpn --remote may.kg --dev tun1 --ifconfig 10.4.0.2 10.4.0.1 --verb 9
| |
| </pre>
| |
| | |
| On May:
| |
| ping 10.4.0.2
| |
| | |
| On Jun:
| |
| ping 10.4.0.1
| |
| | |
| '''Example 2:''' A tunnel with static-key security (i.e. using a pre-shared secret)<br>
| |
| '''On May: Server Side'''
| |
| <pre>
| |
| openvpn --remote jun.kg --dev tun1 --ifconfig 10.4.0.1 10.4.0.2 \
| |
| --verb 5 --secret key
| |
| </pre>
| |
| | |
| '''On Jun: Client Side'''
| |
| <pre>
| |
| openvpn --remote may.kg --dev tun1 --ifconfig 10.4.0.2 10.4.0.1 \
| |
| --verb 5 --secret key
| |
| </pre>
| |
| | |
| On May:
| |
| ping 10.4.0.2
| |
| | |
| On Jun:
| |
| ping 10.4.0.1
| |
| | |
| '''Example 3:''' A tunnel with full TLS-based security <br>
| |
| '''On May: Server Side'''
| |
| <pre>
| |
| openvpn --remote jun.kg --dev tun1 --ifconfig 10.4.0.1 10.4.0.2 \
| |
| --tls-client --ca tmp-ca.crt --cert client.crt --key client.key \
| |
| --reneg-sec 60 --verb 5
| |
| </pre>
| |
| | |
| '''On Jun: Client Side'''
| |
| <pre>
| |
| openvpn --remote may.kg --dev tun1 --ifconfig 10.4.0.2 10.4.0.1 \
| |
| --tls-server --ca tmp-ca.crt --cert server.crt --key server.key \
| |
| --reneg-sec 60 --verb 5 --dh dh1024.pem
| |
| </pre>
| |
| | |
| On May:
| |
| | |
| ping 10.4.0.2
| |
| | |
| On Jun:
| |
| | |
| ping 10.4.0.1
| |
| | |
| == External Links ==
| |
| | |
| * http://dmalloc.com/
| |
| * http://valgrind.org/
| |
| * http://www.oberhumer.com/opensource/lzo/
| |
| * http://openvpn.net/
| |
| * http://openvpn.net/howto.html
| |
| * http://openvpn.net/1xhowto.html (Old-v1.06)
| |
| * http://openvpn.net/man.html
| |