[2024-feb-29] Sad news: Eric Layton aka Nocturnal Slacker aka vtel57 passed away on Feb 26th, shortly after hospitalization. He was one of our Wiki's most prominent admins. He will be missed.
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Both sides previous revisionPrevious revisionNext revision | Previous revisionNext revisionBoth sides next revision | ||
howtos:network_services:openvpn [2013/05/28 19:42 (UTC)] – updated rc.firewall for better slackware-current and better structure chrisabela | howtos:network_services:openvpn [2018/03/02 00:14 (UTC)] – Correct references to the name OpenVPN, give them consistent casing. bifferos | ||
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===== 2. Scope and Objective ===== | ===== 2. Scope and Objective ===== | ||
- | The objective of this how-to | + | The objective of this article |
- | The emphasis | + | The emphasis is to provide a reliable method that can be easily |
- | This document | + | This article |
===== 3. Installation ===== | ===== 3. Installation ===== | ||
- | Openvpn is already installed on Slackware if a default installation was followed. If this was not the case, then it is available from the "n" | + | Openvpn is already installed on Slackware if a default installation was followed. If this was not the case, then the package |
If you want to confirm that Openvpn is indeed installed, you can check it by listing the / | If you want to confirm that Openvpn is indeed installed, you can check it by listing the / | ||
Line 25: | Line 25: | ||
< | < | ||
# ls / | # ls / | ||
- | / | ||
</ | </ | ||
===== 4. Requirements ===== | ===== 4. Requirements ===== | ||
- | A Server and a Client computers would be needed. They would have to be connected to the Internet on two different Routers and different Network Routes. | + | Server and a Client computers would be needed. They would have to be connected to the Internet on two different Routers and different Network Routes. |
==== 4.1. Server DNS ==== | ==== 4.1. Server DNS ==== | ||
- | A URL is normally used to address the Server. This is not mandatory and instead you may use only the Internet IP. However | + | A URL is normally used to address the Server. This is not mandatory and instead you may use only the Internet IP. However |
==== 4.2. Server details ==== | ==== 4.2. Server details ==== | ||
Line 40: | Line 39: | ||
< | < | ||
hostname: server1 | hostname: server1 | ||
- | IP: 192.168.200.199/ | + | IP: 192.168.200.195/ |
URL: servervpn.no-ip.org | URL: servervpn.no-ip.org | ||
Network Interface: eth0 | Network Interface: eth0 | ||
Line 49: | Line 48: | ||
< | < | ||
hostname: client1 | hostname: client1 | ||
- | IP: 192.168.1.234/ | + | IP: 192.168.1.101/ |
Network Interface: wlan0 | Network Interface: wlan0 | ||
</ | </ | ||
Line 55: | Line 54: | ||
==== 4.3 Administrator Rights ==== | ==== 4.3 Administrator Rights ==== | ||
- | You will need to have administrator rights to set up the Openvpn. This applies to both the Server and the Client. | + | You will need to have administrator rights to set up OpenVPN. This applies to both the Server and the Client. |
==== 4.4 Possible Constraints and Possible Solutions for a WiFi equipped Client ==== | ==== 4.4 Possible Constraints and Possible Solutions for a WiFi equipped Client ==== | ||
Line 67: | Line 66: | ||
===== 5. Creating a Public Key Infrastructure (PKI) using the easy-rsa Scripts ===== | ===== 5. Creating a Public Key Infrastructure (PKI) using the easy-rsa Scripts ===== | ||
- | The PKI may be created on any computer with an Openvpn | + | The PKI may be created on any computer with a VPN installation, |
- | + | ||
- | The easy-rsa scripts referred | + | |
- | + | ||
- | It is not recommended | + | |
- | + | ||
- | Copy the whole easy-rsa | + | |
< | < | ||
- | # cp -r /usr/doc/ | + | # cd |
- | # cd /root/easy-rsa/2.0/ | + | # git clone http://github.com/OpenVPN/easy-rsa |
</ | </ | ||
- | Find the vars file. As a minimum | + | and then archive |
< | < | ||
- | KEY_COUNTRY | + | # tar cvf easy-rsa.tar easy-rsa |
- | KEY_PROVINCE | + | |
- | KEY_ORG | + | |
- | KEY_EMAIL | + | |
</ | </ | ||
- | The purpose of this recommendation is to assure consistency in the default values of some following steps that need to be followed. You should not be really worried about the exact meaning or the correctness of the chosen entries as the actual values will have no bearing on the success or failure of this exercise. | + | ==== 5.1 Create |
- | The following is my complete vars file. You may note some additional entries that were entered. Most of these are meant to enhance the range of default values that will be immediately available, thus increasing the chances of a successful creation of the PKI. | + | Follow |
< | < | ||
- | # easy-rsa | + | # cd easy-rsa/easyrsa3 |
- | + | ||
- | # NOTE: If you installed from an RPM, | + | |
- | # don't edit this file in place in | + | |
- | # /usr/ | + | |
- | # instead, you should copy the whole | + | |
- | # easy-rsa directory to another location | + | |
- | # (such as / | + | |
- | # edits will not be wiped out by a future | + | |
- | # OpenVPN package upgrade. | + | |
- | + | ||
- | # This variable should point to | + | |
- | # the top level of the easy-rsa | + | |
- | # tree. | + | |
- | export EASY_RSA=" | + | |
- | + | ||
- | # | + | |
- | # This variable should point to | + | |
- | # the requested executables | + | |
- | # | + | |
- | export OPENSSL=" | + | |
- | export PKCS11TOOL=" | + | |
- | export GREP=" | + | |
- | + | ||
- | + | ||
- | # This variable should point to | + | |
- | # the openssl.cnf file included | + | |
- | # with easy-rsa. | + | |
- | export KEY_CONFIG=`$EASY_RSA/ | + | |
- | + | ||
- | # Edit this variable to point to | + | |
- | # your soon-to-be-created key | + | |
- | # directory. | + | |
- | # | + | |
- | # WARNING: clean-all will do | + | |
- | # a rm -rf on this directory | + | |
- | # so make sure you define | + | |
- | # it correctly! | + | |
- | export KEY_DIR=" | + | |
- | + | ||
- | # Issue rm -rf warning | + | |
- | echo NOTE: If you run ./ | + | |
- | + | ||
- | # PKCS11 fixes | + | |
- | export PKCS11_MODULE_PATH=" | + | |
- | export PKCS11_PIN=" | + | |
- | + | ||
- | # Increase this to 2048 if you | + | |
- | # are paranoid. | + | |
- | # down TLS negotiation performance | + | |
- | # as well as the one-time DH parms | + | |
- | # generation process. | + | |
- | export KEY_SIZE=2048 | + | |
- | + | ||
- | # In how many days should the root CA key expire? | + | |
- | export CA_EXPIRE=3650 | + | |
- | + | ||
- | # In how many days should certificates expire? | + | |
- | export KEY_EXPIRE=3650 | + | |
- | + | ||
- | # These are the default values for fields | + | |
- | # which will be placed in the certificate. | + | |
- | # Don't leave any of these fields blank. | + | |
- | export KEY_COUNTRY=" | + | |
- | export KEY_PROVINCE=" | + | |
- | export KEY_CITY=" | + | |
- | export KEY_ORG=" | + | |
- | #export KEY_EMAIL=" | + | |
- | export KEY_EMAIL=support@abcdef.com | + | |
- | export KEY_CN=server1 | + | |
- | export KEY_NAME=server1 | + | |
- | export KEY_OU="" | + | |
- | export PKCS11_MODULE_PATH=changeme | + | |
- | export PKCS11_PIN=1234 | + | |
</ | </ | ||
- | Source | + | Create |
< | < | ||
- | # source | + | # ./easyrsa init-pki |
- | NOTE: If you run ./clean-all, I will be doing a rm -rf on / | + | # ./easyrsa build-ca |
</ | </ | ||
- | Proceed like this: | + | Enter a PEM pass phrase, reverify it and then enter a name for the server. In this article I am using the hostnames for clarity (in this case: server1), but you may choose any name. |
+ | |||
+ | Then generate the request: | ||
< | < | ||
- | # ./clean-all | + | # ./easyrsa gen-req server1 |
- | # ./ | + | |
- | Generating a 2048 bit RSA private key | + | |
- | .....................+++ | + | |
- | .......................................................................+++ | + | |
- | writing new private key to ' | + | |
- | ----- | + | |
- | You are about to be asked to enter information that will be incorporated | + | |
- | into your certificate request. | + | |
- | What you are about to enter is what is called a Distinguished Name or a DN. | + | |
- | There are quite a few fields but you can leave some blank | + | |
- | For some fields there will be a default value, | + | |
- | If you enter ' | + | |
- | ----- | + | |
- | Country Name (2 letter code) [MT]: | + | |
- | State or Province Name (full name) [Malta]: | + | |
- | Locality Name (eg, city) [Valletta]: | + | |
- | Organization Name (eg, company) [ABCDEF Co. Ltd.]: | + | |
- | Organizational Unit Name (eg, section) []: | + | |
- | Common Name (eg, your name or your server' | + | |
- | Name [server1]: | + | |
- | Email Address [support@abcdef.com]: | + | |
</ | </ | ||
- | **Hint: The less information you enter, the less likely it will cause you problems later on.** | + | You will be prompted for another PEM pass phrase to reverify it and to confirm that the name of the entity is indeed server1. Now you may proceed to sign this request: |
< | < | ||
- | # ./build-key-server server1 | + | # ./easyrsa sign-req server server1 |
</ | </ | ||
- | **Do not enter a challenge password or company name when prompted.** | + | Confirm the request by entering “yes”, then enter original ca PEM passphrase. |
+ | |||
+ | Now create two additional key files: | ||
< | < | ||
- | Generating a 2048 bit RSA private key | + | # cd / |
- | ........................+++ | + | # openssl dhparam -out dh2048.pem 2048 |
- | ................................................+++ | + | # cd / |
- | writing new private key to ' | + | # / |
- | ----- | + | </code> |
- | You are about to be asked to enter information that will be incorporated | + | |
- | into your certificate request. | + | |
- | What you are about to enter is what is called a Distinguished Name or a DN. | + | |
- | There are quite a few fields but you can leave some blank | + | |
- | For some fields there will be a default value, | + | |
- | If you enter ' | + | |
- | ----- | + | |
- | Country Name (2 letter | + | |
- | State or Province Name (full name) [Malta]: | + | |
- | Locality Name (eg, city) [Valletta]: | + | |
- | Organization Name (eg, company) [ABCDEF Co. Ltd.]: | + | |
- | Organizational Unit Name (eg, section) []: | + | |
- | Common Name (eg, your name or your server' | + | |
- | Name [server1]: | + | |
- | Email Address [support@abcdef.com]: | + | |
- | Please enter the following ' | + | ==== 5.2 Create |
- | to be sent with your certificate request | + | |
- | A challenge password []: | + | |
- | An optional company name []: | + | |
- | Using configuration from / | + | |
- | Check that the request matches the signature | + | |
- | Signature ok | + | |
- | The Subject' | + | |
- | countryName | + | |
- | stateOrProvinceName | + | |
- | localityName | + | |
- | organizationName | + | |
- | commonName | + | |
- | name : | + | |
- | emailAddress | + | |
- | Certificate is to be certified until Jan 18 19:37:43 2023 GMT (3650 days) | + | |
- | Sign the certificate? | + | |
+ | Follow these steps on the Client to create the needed keys and certificates: | ||
- | 1 out of 1 certificate requests certified, commit? [y/n]y | + | You will need the easy-rsa scripts, so you can copy easy-rsa tarball from the Server to the Client and extract it: |
- | Write out database with 1 new entries | + | |
- | Data Base Updated | + | |
- | </ | + | |
< | < | ||
- | # ./build-dh | + | # cd |
- | This is going to take a long time | + | # tar xvf easy-rsa.tar |
- | ..................+........................................................................................................... | + | |
- | ................................................................. | + | |
</ | </ | ||
+ | |||
+ | Now create the PKI and generate the request: | ||
< | < | ||
- | # ./build-key client1 | + | # cd easy-rsa/ |
+ | # ./easyrsa init-pki | ||
+ | # ./easyrsa gen-req client1 | ||
</ | </ | ||
- | ** Do not enter a challenge password or company name when prompted.** | + | You will be prompted |
- | < | + | Copy pki/reqs/client1.req back to the Server. |
- | Generating a 2048 bit RSA private key | + | |
- | ...............................................................................................+++ | + | |
- | ..+++ | + | |
- | writing new private key to 'client1.key' | + | |
- | ----- | + | |
- | You are about to be asked to enter information that will be incorporated | + | |
- | into your certificate request. | + | |
- | What you are about to enter is what is called a Distinguished Name or a DN. | + | |
- | There are quite a few fields but you can leave some blank | + | |
- | For some fields there will be a default value, | + | |
- | If you enter ' | + | |
- | ----- | + | |
- | Country Name (2 letter code) [MT]: | + | |
- | State or Province Name (full name) [Malta]: | + | |
- | Locality Name (eg, city) [Valletta]: | + | |
- | Organization Name (eg, company) [ABCDEF Co. Ltd.]: | + | |
- | Organizational Unit Name (eg, section) []: | + | |
- | Common Name (eg, your name or your server' | + | |
- | Name [server1]: | + | |
- | Email Address [support@abcdef.com]: | + | |
- | Please enter the following ' | + | === 5.2.1 Sign the Client' |
- | to be sent with your certificate request | + | |
- | A challenge password []: | + | |
- | An optional company name []: | + | |
- | Using configuration from / | + | |
- | Check that the request matches the signature | + | |
- | Signature ok | + | |
- | The Subject' | + | |
- | countryName | + | |
- | stateOrProvinceName | + | |
- | localityName | + | |
- | organizationName | + | |
- | commonName | + | |
- | name : | + | |
- | emailAddress | + | |
- | Certificate is to be certified until Jan 18 19:42:33 2023 GMT (3650 days) | + | |
- | Sign the certificate? | + | |
- | + | For the purpose | |
- | 1 out of 1 certificate requests certified, commit? [y/n]y | + | |
- | Write out database with 1 new entries | + | |
- | Data Base Updated | + | |
- | </code> | + | |
< | < | ||
- | # openvpn --genkey --secret /root/easy-rsa/2.0/keys/ta.key | + | # cd $HOME/easy-rsa/easyrsa3 |
+ | # ./easyrsa import-req $HOME/openvpn/ | ||
+ | # ./easyrsa sign-req client client1 | ||
</ | </ | ||
+ | |||
+ | When prompted enter “yes” and the server1 CA PEM pass phrase. | ||
+ | |||
+ | Copy the generated $HOME/ | ||
+ | back to the client. | ||
===== 6. Setting up the Server ===== | ===== 6. Setting up the Server ===== | ||
Line 326: | Line 162: | ||
< | < | ||
- | # cp /root/easy-rsa/2.0/keys/{ca.crt, | + | # cp $HOME/easy-rsa/easyrsa3/pki/ca.crt \ |
> / | > / | ||
- | # cp /root/easy-rsa/2.0/keys/{server1.key,ta.key} \ | + | # cp $HOME/easy-rsa/easyrsa3/pki/issued/server1.crt \ |
+ | > / | ||
+ | # cp $HOME/ | ||
> / | > / | ||
</ | </ | ||
- | Restrict | + | If you want to run the server as a daemon on system boot, it's necessary to remove the pass-phrase from the server1.key file first. |
< | < | ||
- | # chmod 700 / | + | # cd / |
+ | # openssl rsa -in server1.key -out tmp.key | ||
+ | # mv tmp.key server1.key | ||
+ | # chmod 600 server1.key | ||
</ | </ | ||
- | On the Server machine copy the sample server.conf onto the openvpn's configuration directory. | + | Copy the sample server.conf |
< | < | ||
- | # cp /usr/doc/openvpn-2.2.2/ | + | # cd /tmp/ |
+ | # wget -c \ | ||
+ | > ftp:// | ||
+ | # cd /usr/src/ | ||
+ | # tar xvf /tmp/openvpn-*.tar.?z | ||
+ | </ | ||
+ | |||
+ | Copy the file server.conf contained in the source to the OpenVPN configuration directory: | ||
+ | |||
+ | < | ||
+ | # cp openvpn-*/ | ||
> / | > / | ||
</ | </ | ||
Line 360: | Line 211: | ||
;user nobody | ;user nobody | ||
;group nobody | ;group nobody | ||
+ | |||
+ | ; | ||
</ | </ | ||
- | To | + | To: |
< | < | ||
Line 375: | Line 228: | ||
user nobody | user nobody | ||
group nobody | group nobody | ||
+ | |||
+ | log-append | ||
</ | </ | ||
- | **Note** that comments in server.conf | + | Finally add the following to / |
- | Copy the rc.openvpn-server listed hereunder and place under /etc/rc.d/ | + | < |
+ | # If you want to use OpenVPN as a daemon, uncomment this line. | ||
+ | # Generally speaking, servers should run OpenVPN as a daemon | ||
+ | daemon | ||
+ | </ | ||
+ | |||
+ | < | ||
+ | |||
+ | My full server.conf is the following: | ||
+ | |||
+ | < | ||
+ | ################################################# | ||
+ | # Sample OpenVPN 2.0 config file for # | ||
+ | # multi-client server. | ||
+ | # # | ||
+ | # This file is for the server side # | ||
+ | # of a many-clients <-> one-server | ||
+ | # OpenVPN configuration. | ||
+ | # # | ||
+ | # OpenVPN also supports | ||
+ | # single-machine <-> single-machine | ||
+ | # configurations (See the Examples page # | ||
+ | # on the web site for more info). | ||
+ | # # | ||
+ | # This config should work on Windows | ||
+ | # or Linux/BSD systems. | ||
+ | # Windows to quote pathnames and use # | ||
+ | # double backslashes, | ||
+ | # " | ||
+ | # # | ||
+ | # Comments are preceded with '#' | ||
+ | ################################################# | ||
+ | |||
+ | # Which local IP address should OpenVPN | ||
+ | # listen on? (optional) | ||
+ | ;local a.b.c.d | ||
+ | |||
+ | # Which TCP/UDP port should OpenVPN listen on? | ||
+ | # If you want to run multiple OpenVPN instances | ||
+ | # on the same machine, use a different port | ||
+ | # number for each one. You will need to | ||
+ | # open up this port on your firewall. | ||
+ | port 1194 | ||
+ | |||
+ | # TCP or UDP server? | ||
+ | ;proto tcp | ||
+ | proto udp | ||
+ | |||
+ | # "dev tun" will create a routed IP tunnel, | ||
+ | # "dev tap" will create an ethernet tunnel. | ||
+ | # Use "dev tap0" if you are ethernet bridging | ||
+ | # and have precreated a tap0 virtual interface | ||
+ | # and bridged it with your ethernet interface. | ||
+ | # If you want to control access policies | ||
+ | # over the VPN, you must create firewall | ||
+ | # rules for the the TUN/TAP interface. | ||
+ | # On non-Windows systems, you can give | ||
+ | # an explicit unit number, such as tun0. | ||
+ | # On Windows, use " | ||
+ | # On most systems, the VPN will not function | ||
+ | # unless you partially or fully disable | ||
+ | # the firewall for the TUN/TAP interface. | ||
+ | ;dev tap | ||
+ | dev tun | ||
+ | |||
+ | # Windows needs the TAP-Win32 adapter name | ||
+ | # from the Network Connections panel if you | ||
+ | # have more than one. On XP SP2 or higher, | ||
+ | # you may need to selectively disable the | ||
+ | # Windows firewall for the TAP adapter. | ||
+ | # Non-Windows systems usually don't need this. | ||
+ | ;dev-node MyTap | ||
+ | |||
+ | # SSL/TLS root certificate (ca), certificate | ||
+ | # (cert), and private key (key). | ||
+ | # and the server must have their own cert and | ||
+ | # key file. The server and all clients will | ||
+ | # use the same ca file. | ||
+ | # | ||
+ | # See the " | ||
+ | # of scripts for generating RSA certificates | ||
+ | # and private keys. Remember to use | ||
+ | # a unique Common Name for the server | ||
+ | # and each of the client certificates. | ||
+ | # | ||
+ | # Any X509 key management system can be used. | ||
+ | # OpenVPN can also use a PKCS #12 formatted key file | ||
+ | # (see " | ||
+ | ca /etc/openvpn/ | ||
+ | cert / | ||
+ | key / | ||
+ | |||
+ | # Diffie hellman parameters. | ||
+ | # Generate your own with: | ||
+ | # | ||
+ | # Substitute 2048 for 1024 if you are using | ||
+ | # 2048 bit keys. | ||
+ | dh / | ||
+ | |||
+ | # Configure | ||
+ | # for OpenVPN to draw client addresses from. | ||
+ | # The server will take 10.8.0.1 for itself, | ||
+ | # the rest will be made available to clients. | ||
+ | # Each client will be able to reach the server | ||
+ | # on 10.8.0.1. Comment this line out if you are | ||
+ | # ethernet bridging. See the man page for more info. | ||
+ | server 10.8.0.0 255.255.255.0 | ||
+ | |||
+ | # Maintain a record of client <-> virtual IP address | ||
+ | # associations in this file. If OpenVPN goes down or | ||
+ | # is restarted, reconnecting clients can be assigned | ||
+ | # the same virtual IP address from the pool that was | ||
+ | # previously assigned. | ||
+ | ifconfig-pool-persist ipp.txt | ||
+ | |||
+ | # Configure server mode for ethernet bridging. | ||
+ | # You must first use your OS's bridging capability | ||
+ | # to bridge the TAP interface with the ethernet | ||
+ | # NIC interface. | ||
+ | # IP/netmask on the bridge interface, here we | ||
+ | # assume 10.8.0.4/ | ||
+ | # must set aside an IP range in this subnet | ||
+ | # (start=10.8.0.50 end=10.8.0.100) to allocate | ||
+ | # to connecting clients. | ||
+ | # out unless you are ethernet bridging. | ||
+ | ; | ||
+ | |||
+ | # Configure server mode for ethernet bridging | ||
+ | # using a DHCP-proxy, where clients talk | ||
+ | # to the OpenVPN server-side DHCP server | ||
+ | # to receive their IP address allocation | ||
+ | # and DNS server addresses. | ||
+ | # your OS's bridging capability to bridge the TAP | ||
+ | # interface with the ethernet NIC interface. | ||
+ | # Note: this mode only works on clients (such as | ||
+ | # Windows), where the client-side TAP adapter is | ||
+ | # bound to a DHCP client. | ||
+ | ; | ||
+ | |||
+ | # Push routes to the client to allow it | ||
+ | # to reach other private subnets behind | ||
+ | # the server. | ||
+ | # private subnets will also need | ||
+ | # to know to route the OpenVPN client | ||
+ | # address pool (10.8.0.0/ | ||
+ | # back to the OpenVPN server. | ||
+ | ;push "route 192.168.10.0 255.255.255.0" | ||
+ | ;push "route 192.168.20.0 255.255.255.0" | ||
+ | |||
+ | # To assign specific IP addresses to specific | ||
+ | # clients or if a connecting client has a private | ||
+ | # subnet behind it that should also have VPN access, | ||
+ | # use the subdirectory " | ||
+ | # configuration files (see man page for more info). | ||
+ | |||
+ | # EXAMPLE: Suppose the client | ||
+ | # having the certificate common name " | ||
+ | # also has a small subnet behind his connecting | ||
+ | # machine, such as 192.168.40.128/ | ||
+ | # First, uncomment out these lines: | ||
+ | ; | ||
+ | ;route 192.168.40.128 255.255.255.248 | ||
+ | # Then create a file ccd/ | ||
+ | # | ||
+ | # This will allow Thelonious' | ||
+ | # access the VPN. This example will only work | ||
+ | # if you are routing, not bridging, i.e. you are | ||
+ | # using "dev tun" and " | ||
+ | |||
+ | # EXAMPLE: Suppose you want to give | ||
+ | # Thelonious a fixed VPN IP address of 10.9.0.1. | ||
+ | # First uncomment out these lines: | ||
+ | ; | ||
+ | ;route 10.9.0.0 255.255.255.252 | ||
+ | # Then add this line to ccd/ | ||
+ | # | ||
+ | |||
+ | # Suppose that you want to enable different | ||
+ | # firewall access policies for different groups | ||
+ | # of clients. | ||
+ | # (1) Run multiple OpenVPN daemons, one for each | ||
+ | # | ||
+ | # for each group/ | ||
+ | # (2) (Advanced) Create a script to dynamically | ||
+ | # | ||
+ | # from different clients. | ||
+ | # page for more info on learn-address script. | ||
+ | ; | ||
+ | |||
+ | # If enabled, this directive will configure | ||
+ | # all clients to redirect their default | ||
+ | # network gateway through the VPN, causing | ||
+ | # all IP traffic such as web browsing and | ||
+ | # and DNS lookups to go through the VPN | ||
+ | # (The OpenVPN server machine may need to NAT | ||
+ | # or bridge the TUN/TAP interface to the internet | ||
+ | # in order for this to work properly). | ||
+ | ;push " | ||
+ | |||
+ | # Certain Windows-specific network settings | ||
+ | # can be pushed to clients, such as DNS | ||
+ | # or WINS server addresses. | ||
+ | # http:// | ||
+ | # The addresses below refer to the public | ||
+ | # DNS servers provided by opendns.com. | ||
+ | ;push " | ||
+ | ;push " | ||
+ | |||
+ | # Uncomment this directive to allow different | ||
+ | # clients to be able to " | ||
+ | # By default, clients will only see the server. | ||
+ | # To force clients to only see the server, you | ||
+ | # will also need to appropriately firewall the | ||
+ | # server' | ||
+ | ; | ||
+ | |||
+ | # Uncomment this directive if multiple clients | ||
+ | # might connect with the same certificate/ | ||
+ | # files or common names. | ||
+ | # only for testing purposes. | ||
+ | # each client should have its own certificate/ | ||
+ | # pair. | ||
+ | # | ||
+ | # IF YOU HAVE NOT GENERATED INDIVIDUAL | ||
+ | # CERTIFICATE/ | ||
+ | # EACH HAVING ITS OWN UNIQUE " | ||
+ | # UNCOMMENT THIS LINE OUT. | ||
+ | ; | ||
+ | |||
+ | # The keepalive directive causes ping-like | ||
+ | # messages to be sent back and forth over | ||
+ | # the link so that each side knows when | ||
+ | # the other side has gone down. | ||
+ | # Ping every 10 seconds, assume that remote | ||
+ | # peer is down if no ping received during | ||
+ | # a 120 second time period. | ||
+ | keepalive 10 120 | ||
+ | |||
+ | # For extra security beyond that provided | ||
+ | # by SSL/TLS, create an "HMAC firewall" | ||
+ | # to help block DoS attacks and UDP port flooding. | ||
+ | # | ||
+ | # Generate with: | ||
+ | # | ||
+ | # | ||
+ | # The server and each client must have | ||
+ | # a copy of this key. | ||
+ | # The second parameter should be ' | ||
+ | # on the server and ' | ||
+ | tls-auth / | ||
+ | |||
+ | # Select a cryptographic cipher. | ||
+ | # This config item must be copied to | ||
+ | # the client config file as well. | ||
+ | ;cipher BF-CBC | ||
+ | ;cipher AES-128-CBC | ||
+ | ;cipher DES-EDE3-CBC | ||
+ | |||
+ | # Enable compression on the VPN link. | ||
+ | # If you enable it here, you must also | ||
+ | # enable it in the client config file. | ||
+ | comp-lzo | ||
+ | |||
+ | # The maximum number of concurrently connected | ||
+ | # clients we want to allow. | ||
+ | ; | ||
+ | |||
+ | # It's a good idea to reduce the OpenVPN | ||
+ | # daemon' | ||
+ | # | ||
+ | # You can uncomment this out on | ||
+ | # non-Windows systems. | ||
+ | user nobody | ||
+ | group nobody | ||
+ | |||
+ | # The persist options will try to avoid | ||
+ | # accessing certain resources on restart | ||
+ | # that may no longer be accessible because | ||
+ | # of the privilege downgrade. | ||
+ | persist-key | ||
+ | persist-tun | ||
+ | |||
+ | # Output a short status file showing | ||
+ | # current connections, | ||
+ | # and rewritten every minute. | ||
+ | status openvpn-status.log | ||
+ | |||
+ | # By default, log messages will go to the syslog (or | ||
+ | # on Windows, if running as a service, they will go to | ||
+ | # the " | ||
+ | # Use log or log-append to override this default. | ||
+ | # " | ||
+ | # while " | ||
+ | # or the other (but not both). | ||
+ | ;log | ||
+ | log-append | ||
+ | |||
+ | # Set the appropriate level of log | ||
+ | # file 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 | ||
+ | |||
+ | # Silence repeating messages. | ||
+ | # sequential messages of the same message | ||
+ | # category will be output to the log. | ||
+ | ;mute 20 | ||
+ | |||
+ | # If you want to use OpenVPN as a daemon, uncomment this line. | ||
+ | # Generally speaking, servers should run OpenVPN as a daemon | ||
+ | daemon | ||
+ | </ | ||
+ | |||
+ | < | ||
+ | |||
+ | Copy the rc.openvpn | ||
< | < | ||
# | # | ||
# | # | ||
- | # / | + | # / |
- | # | + | |
- | # Start/ | + | |
# | # | ||
- | # To make OpenVPN start automatically at boot, make this | + | # Start/stop/restart the OpenVPN server. |
- | # file executable: | + | # |
- | # | + | |
ovpn_start() { | ovpn_start() { | ||
if [ -x / | if [ -x / | ||
echo " | echo " | ||
- | / | + | / |
fi | fi | ||
} | } | ||
Line 427: | Line 597: | ||
< | < | ||
- | # chmod 755 / | + | # chmod 755 / |
+ | </ | ||
+ | |||
+ | Eventually when you start OpenVPN on the server, you may read / | ||
+ | |||
+ | < | ||
+ | # cat / | ||
</ | </ | ||
===== 7. Port Forwarding ===== | ===== 7. Port Forwarding ===== | ||
- | You will need to forward traffic from the port you have chosen for Openvpn | + | You will need to forward traffic from the port you have chosen for OpenVPN |
- | In case if you have misplaced such documentation, | + | In case if you have misplaced such documentation, |
===== 8. Setting up the Client ===== | ===== 8. Setting up the Client ===== | ||
- | On the client | + | On the Client |
+ | |||
+ | Download the OpenVPN source tarball and extracted it as explained in Chapter 6, then proceed to copy the included configuration file for clients: | ||
< | < | ||
- | # cp /usr/doc/openvpn-2.2.2/ | + | # cp /usr/src/openvpn-*/sample/ |
> / | > / | ||
</ | </ | ||
Line 475: | Line 653: | ||
</ | </ | ||
- | **Note** that comments in client.conf may be either # or ; The former are used to comment out text while the latter are for commented out configuration lines. This should help you a lot in the configuration process. | + | < |
- | You will need the following files that were generated by the easy-rsa scripts: | + | You will need this file that were generated by the Client' |
+ | |||
+ | < | ||
+ | $HOME/ | ||
+ | </ | ||
+ | |||
+ | and the following from the Server' | ||
< | < | ||
ca.crt | ca.crt | ||
- | client1.crt | ||
- | client1.key | ||
ta.key | ta.key | ||
</ | </ | ||
+ | |||
+ | You will also need client1.crt generated by the Server as explained above in Chapter 5.2.1. | ||
Place these files as indicated in client.conf. So ca.crt and client1.crt go under / | Place these files as indicated in client.conf. So ca.crt and client1.crt go under / | ||
- | Copy the following rc.openvpn-client | + | Also in client.conf, comment out the line: |
< | < | ||
- | #!/bin/sh | + | ns-cert-type server |
- | # | + | </code> |
- | # / | + | |
- | # | + | |
- | # Start/stop/ | + | |
- | # | + | |
- | ovpn_start() { | + | and insert the line: |
- | if [ -x / | + | |
- | echo " | + | |
- | / | + | |
- | fi | + | |
- | } | + | |
- | ovpn_stop() { | + | < |
- | | + | remote-cert-tls server |
- | } | + | |
- | + | ||
- | ovpn_restart() { | + | |
- | ovpn_stop | + | |
- | sleep 2 | + | |
- | ovpn_start | + | |
- | } | + | |
- | + | ||
- | case " | + | |
- | ' | + | |
- | ovpn_start | + | |
- | ;; | + | |
- | ' | + | |
- | ovpn_stop | + | |
- | ;; | + | |
- | ' | + | |
- | ovpn_restart | + | |
- | ;; | + | |
- | *) | + | |
- | echo " | + | |
- | esac | + | |
</ | </ | ||
- | Then give it executable permissions: | + | My full client.conf is the following: |
< | < | ||
- | # chmod +x /etc/rc.d/rc.openvpn-client | + | ############################################## |
- | </ | + | # Sample client-side OpenVPN 2.0 config file # |
+ | # for connecting to multi-client server. | ||
+ | # # | ||
+ | # This configuration can be used by multiple # | ||
+ | # clients, however each client should have # | ||
+ | # its own cert and key files. | ||
+ | # # | ||
+ | # On Windows, you might want to rename this # | ||
+ | # file so it has a .ovpn extension | ||
+ | ############################################## | ||
+ | |||
+ | # Specify that we are a client and that we | ||
+ | # will be pulling certain config file directives | ||
+ | # from the server. | ||
+ | client | ||
+ | |||
+ | # Use the same setting as you are using on | ||
+ | # the server. | ||
+ | # On most systems, the VPN will not function | ||
+ | # unless you partially or fully disable | ||
+ | # the firewall for the TUN/TAP interface. | ||
+ | ;dev tap | ||
+ | dev tun | ||
+ | |||
+ | # Windows needs the TAP-Win32 adapter name | ||
+ | # from the Network Connections panel | ||
+ | # if you have more than one. On XP SP2, | ||
+ | # you may need to disable the firewall | ||
+ | # for the TAP adapter. | ||
+ | ;dev-node MyTap | ||
+ | |||
+ | # Are we connecting to a TCP or | ||
+ | # UDP server? | ||
+ | # on the server. | ||
+ | ;proto tcp | ||
+ | proto udp | ||
+ | |||
+ | # The hostname/IP and port of the server. | ||
+ | # You can have multiple remote entries | ||
+ | # to load balance between the servers. | ||
+ | remote servervpn.no-ip.org 1194 | ||
+ | ;remote my-server-2 1194 | ||
+ | |||
+ | # Choose a random host from the remote | ||
+ | # list for load-balancing. | ||
+ | # try hosts in the order specified. | ||
+ | ; | ||
+ | |||
+ | # Keep trying indefinitely to resolve the | ||
+ | # host name of the OpenVPN server. | ||
+ | # on machines which are not permanently connected | ||
+ | # to the internet such as laptops. | ||
+ | resolv-retry infinite | ||
+ | |||
+ | # Most clients don't need to bind to | ||
+ | # a specific local port number. | ||
+ | nobind | ||
+ | |||
+ | # Downgrade privileges after initialization (non-Windows only) | ||
+ | user nobody | ||
+ | group nobody | ||
+ | |||
+ | # Try to preserve some state across restarts. | ||
+ | persist-key | ||
+ | persist-tun | ||
+ | |||
+ | # If you are connecting through an | ||
+ | # HTTP proxy to reach the actual OpenVPN | ||
+ | # server, put the proxy server/IP and | ||
+ | # port number here. See the man page | ||
+ | # if your proxy server requires | ||
+ | # authentication. | ||
+ | ; | ||
+ | ;http-proxy [proxy server] [proxy port #] | ||
+ | |||
+ | # Wireless networks often produce a lot | ||
+ | # of duplicate packets. | ||
+ | # to silence duplicate packet warnings. | ||
+ | ; | ||
+ | |||
+ | # SSL/TLS parms. | ||
+ | # See the server config file for more | ||
+ | # description. | ||
+ | # a separate .crt/.key file pair | ||
+ | # for each client. | ||
+ | # file can be used for all clients. | ||
+ | ca /etc/openvpn/ | ||
+ | cert / | ||
+ | key /etc/openvpn/ | ||
+ | |||
+ | # Verify server certificate by checking | ||
+ | # that the certicate has the nsCertType | ||
+ | # field set to " | ||
+ | # important precaution to protect against | ||
+ | # a potential attack discussed here: | ||
+ | # http:// | ||
+ | # | ||
+ | # To use this feature, you will need to generate | ||
+ | # your server certificates with the nsCertType | ||
+ | # field set to " | ||
+ | # script in the easy-rsa folder will do this. | ||
+ | ; | ||
+ | remote-cert-tls server | ||
+ | |||
+ | # If a tls-auth key is used on the server | ||
+ | # then every client | ||
+ | tls-auth / | ||
+ | |||
+ | # Select a cryptographic cipher. | ||
+ | # If the cipher option is used on the server | ||
+ | # then you must also specify it here. | ||
+ | ;cipher x | ||
+ | |||
+ | # Enable compression on the VPN link. | ||
+ | # Don't enable this unless it is also | ||
+ | # enabled in the server config file. | ||
+ | comp-lzo | ||
+ | |||
+ | # Set log file verbosity. | ||
+ | verb 3 | ||
+ | |||
+ | # Silence repeating messages | ||
+ | ;mute 20 | ||
+ | #</ | ||
===== 9. Testing the VPN ===== | ===== 9. Testing the VPN ===== | ||
Line 541: | Line 818: | ||
< | < | ||
- | # / | + | # / |
</ | </ | ||
+ | |||
+ | Enter the Server PEM pass phrase when prompted. | ||
On the Client: | On the Client: | ||
< | < | ||
- | # /etc/rc.d/rc.openvpn-client | + | # /usr/sbin/ |
</ | </ | ||
+ | |||
+ | Enter the Client PEM pass phrase when prompted. To stop OpenVPN on the Client just hit CTRL+C | ||
On both you should see a new network interface called tun0. On the Server, I obtained the following: | On both you should see a new network interface called tun0. On the Server, I obtained the following: | ||
Line 592: | Line 873: | ||
</ | </ | ||
- | To start the openvpn service automatically on boot-up from the Server, include these lines in / | + | ===== 10. Storing the PEM pass phrase in a secure file and Automatic start of service after booting ===== |
+ | |||
+ | To start the OpenVPN service on boot, an entry in / | ||
+ | |||
+ | < | ||
+ | # chmod 600 / | ||
+ | </ | ||
+ | |||
+ | On the Server, edit /etc/openvpn/ | ||
+ | |||
+ | < | ||
+ | askpass / | ||
+ | auth-nocache | ||
+ | </ | ||
+ | |||
+ | This may be repeated also on the Client, just edit / | ||
+ | |||
+ | To start the OpenVPN | ||
< | < | ||
- | # Start the OpenVPN | + | # Start the OpenVPN |
- | if [ -x / | + | if [ -x / |
- | / | + | / |
fi | fi | ||
</ | </ | ||
- | ===== 10. IP Routing ===== | + | ===== 11. IP Routing ===== |
Up to now we have created a tunnel device on both the Server and the Client called tun0 which is visible only to these two machines. However more work is needed to route the Client' | Up to now we have created a tunnel device on both the Server and the Client called tun0 which is visible only to these two machines. However more work is needed to route the Client' | ||
- | ==== 10.1 Server Configuration ==== | + | ==== 11.1 Server Configuration ==== |
Enable IP forwarding: | Enable IP forwarding: | ||
Line 635: | Line 933: | ||
push "route 192.168.200.0 255.255.255.0" | push "route 192.168.200.0 255.255.255.0" | ||
- | client-config-dir ccd | + | client-config-dir |
route 192.168.1.0 255.255.255.0 | route 192.168.1.0 255.255.255.0 | ||
Line 645: | Line 943: | ||
Naturally replace 192.168.200.0 255.255.255.0 with the Server' | Naturally replace 192.168.200.0 255.255.255.0 with the Server' | ||
+ | 208.67.222.222 and 208.67.220.220 are the OpenDNS IP addresses. | ||
+ | |||
+ | <note warning> | ||
+ | |||
+ | You can either use the original Client DNS servers or else you may rewrite / | ||
+ | |||
+ | < | ||
+ | # OpenDNS Servers | ||
+ | nameserver 208.67.222.222 | ||
+ | nameserver 208.67.220.220 | ||
+ | </ | ||
+ | |||
+ | According to your routing table however, it is still worth trying to use the DNS servers listed by the Client, I find that they are generally still available, so you would not need to do anything. However do be aware of possible DNS leaks if you are concerned about your privacy. | ||
- | 208.67.222.222 and 208.67.220.220 are the OpenDNS IP addresses. Up to now the DNS push configuration has not been successful. You can either use the original | + | Some users have reported that their Client' |
Next you will have to configure some iptables NAT forwarding on the Server (only). You can do this by first flushing the iptables: | Next you will have to configure some iptables NAT forwarding on the Server (only). You can do this by first flushing the iptables: | ||
Line 674: | Line 985: | ||
< | < | ||
- | #!/bin/sh | + | #!/bin/bash |
- | # Start/ | + | # Start/ |
- | # A VPN server iptable filter rules | + | |
- | + | IPT=/ | |
- | IPT=/ | + | |
+ | firewall_start() { | ||
+ | |||
+ | # flush the iptables | ||
+ | echo -e " | ||
+ | $IPT -F | ||
+ | |||
+ | # policies | ||
+ | $IPT -P OUTPUT DROP | ||
+ | $IPT -P INPUT DROP | ||
+ | $IPT -P FORWARD DROP | ||
- | firewall_start() { | + | $IPT -N SERVICES # services is a custom chain |
- | # Flush the iptables | + | # allowed output |
- | $IPT -F | + | $IPT -A OUTPUT -o lo -j ACCEPT |
+ | $IPT -A OUTPUT -o eth0 -j ACCEPT | ||
+ | $IPT -A OUTPUT -o tun0 -j ACCEPT | ||
- | # Policies | + | # allowed inputs |
- | $IPT -P OUTPUT | + | |
- | $IPT -P INPUT DROP | + | $IPT -A INPUT -m conntrack --ctstate ESTABLISHED, |
- | $IPT -P FORWARD DROP | + | $IPT -A INPUT -j SERVICES # append the services |
- | $IPT -N SERVICES # Services is a custom | + | |
- | # Allowed inputs | + | # allowed forwarding for OpenVPN |
- | | + | $IPT -A FORWARD |
- | $IPT -A INPUT -m conntrack | + | $IPT -A FORWARD -s 10.8.0.0/24 -o eth0 -j ACCEPT |
- | $IPT -A INPUT -j SERVICES # Append the services chain to the input | + | |
- | # Allowed forwards | + | # masquerade the OpenVPN network |
- | $IPT -A FORWARD -i eth0 -o tun0 -m state --state ESTABLISHED, | + | $IPT -t nat -A POSTROUTING |
- | $IPT -A FORWARD | + | |
- | # Masquerade the openvpn network | + | # allow sshd on the default tcp port 22 |
- | $IPT -t nat -A POSTROUTING -s 10.8.0.0/24 ! -d 10.8.0.0/24 -o eth0 -j MASQUERADE | + | |
- | + | ||
- | # Allow services | + | |
- | # Allow vpn on the default udp port 1194 | + | |
- | $IPT -A SERVICES -p udp --dport 1194 -j ACCEPT | + | |
- | # Allow sshd on the default tcp port 22 | + | |
- | $IPT -A SERVICES -p tcp --dport 22 -j ACCEPT | + | |
+ | # allow OpenVPN for the default udp port 1194 | ||
+ | $IPT -A SERVICES -p udp --dport 1194 -j ACCEPT | ||
+ | | ||
+ | echo " | ||
} | } | ||
firewall_stop() { | firewall_stop() { | ||
+ | echo -e " | ||
- | # Polcies | + | # polcies |
+ | $IPT -P OUTPUT ACCEPT | ||
$IPT -P INPUT ACCEPT | $IPT -P INPUT ACCEPT | ||
+ | $IPT -P FORWARD ACCEPT | ||
- | # Flush the iptables | + | # flush the iptables |
$IPT -F | $IPT -F | ||
- | # Delete | + | # delete |
- | $IPT -X SERVICES | + | $IPT -X SERVICES |
- | } | + | echo " |
+ | } | ||
+ | |||
+ | firewall_status() { | ||
+ | $IPT -vL | ||
+ | } | ||
case " | case " | ||
Line 734: | Line 1060: | ||
firewall_start | firewall_start | ||
;; | ;; | ||
+ | ' | ||
+ | firewall_status | ||
+ | ;; | ||
*) | *) | ||
- | echo "Usage $0 start|stop|restart" | + | echo "Usage $0 start|stop|restart|status" |
esac | esac | ||
</ | </ | ||
Line 751: | Line 1080: | ||
</ | </ | ||
- | Now you will you need to do is to restart | + | Restart |
- | ===== 11. Firewalls ===== | + | < |
+ | # / | ||
+ | </ | ||
+ | |||
+ | and reconnect from the Client: | ||
+ | |||
+ | < | ||
+ | # / | ||
+ | </ | ||
+ | |||
+ | ===== 12. Firewalls ===== | ||
- | In the previous chapter we referred to a firewall you may include to protect your Openvpn | + | In the previous chapter we referred to a firewall you may include to protect your OpenVPN |
In order to penetrate through the Client firewall your may want to try changing the port to 443 - normally reserved for https. Using TCP instead of UDP will also help. To make these change you will need to amend / | In order to penetrate through the Client firewall your may want to try changing the port to 443 - normally reserved for https. Using TCP instead of UDP will also help. To make these change you will need to amend / | ||
Line 803: | Line 1142: | ||
You also have to modify your Router' | You also have to modify your Router' | ||
- | ===== 12. References | + | ===== 13. Sources |
(1) http:// | (1) http:// | ||
Line 812: | Line 1151: | ||
(4) http:// | (4) http:// | ||
+ | |||
+ | (5) http:// | ||
* Originally written by [[wiki: | * Originally written by [[wiki: |