Difference between revisions of "OpenVPN"

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(Client config Wintendo)
(Important considerations before use)
 
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Line 1: Line 1:
 
{{Project
 
{{Project
 
|Current=Yes
 
|Current=Yes
|Participants=Jaroslov, Abe
+
|Participants=Jaroslov, Abe, Hans
 
|Locations=Whitespace
 
|Locations=Whitespace
 
|Short description=VPN server
 
|Short description=VPN server
 
}}
 
}}
 +
== Important considerations before use ==
 +
'''Notes'''
 +
* The connection is encrypted and controlled by us until it gets on the ibbt server. After that it's public and goes over the network of ibbt/belnet.
 +
* There is no anonymity implied, public ip will be linked to our vps, the reverse dns even works.
 +
* Remember to switch off your P2P software because the traffic patterns won't disclose the fact that it's just linux iso's. Also if you want to connect it's your duty to verify your machine isn't r00ted.
 +
* IBBT T&A: if they receive a complaint, they will shut the server down. I expect no problems here but please be conscious about it and think of your fellow members ;-)
 +
'''Use cases'''
 +
* safer communication in hostile environments (unencrypted hotspots, certain conferences)
 +
* Direct line onto the local 0x20 network , troll ppl by playing bad music, cause seizures by manipulating the lights, play with local services.
 +
 +
== Setup ==
 +
An OpenVPN server on members.0x20.be, connected to Belnet, hosted by IBBT. There is also a p2p tunnel to the space to provide connectivity to the 0x20 internal network.  Authentication is done with SSL client certificates based on a [[CA|0x20 CA]]. All client certificates signed by the 0x20 CA and with an 'OU=members' are allowed to connect. Future access can be denied by revoking the  client certificate and updating the CRL (Certificate Revocation List).
 +
 +
See below for the steps to connect to the VPN server. Further below is the documentation of the server configurations.
 +
 
== Client ==
 
== Client ==
 
=== Create a new key ===
 
=== Create a new key ===
Linux/windows:
+
Linux/windows/Mac OS X:
 
     $ openssl genrsa -aes256 -out 0x20-vpn-'''your_name_here'''.key 2048
 
     $ openssl genrsa -aes256 -out 0x20-vpn-'''your_name_here'''.key 2048
  
 
=== Create a Certificate signing request ===
 
=== Create a Certificate signing request ===
 +
* The bold values need to be correct, case-sensitive!
 
     $ openssl req -new -key 0x20-vpn-'''your_name_here'''.key -out 0x20-vpn-'''your_name_here'''.csr
 
     $ openssl req -new -key 0x20-vpn-'''your_name_here'''.key -out 0x20-vpn-'''your_name_here'''.csr
             countryName              = BE
+
             countryName              = '''BE'''
             stateOrProvinceName      = Ghent
+
             stateOrProvinceName      = '''Ghent'''
             organizationName          = 0x20
+
            Locality Name            = '''Whitespace'''
 +
             organizationName          = '''0x20'''
 
             organizationalUnitName    = '''members'''
 
             organizationalUnitName    = '''members'''
 
             commonName                = '''your_name_here'''
 
             commonName                = '''your_name_here'''
Line 56: Line 73:
 
     verb 3
 
     verb 3
 
     mute 20
 
     mute 20
 +
 +
=== Client config android ===
 +
Following : http://vpnblog.info/android-openvpn-strongvpn.html
 +
 +
Also assuming you've set it up in linux/windows and have the three files ca/cert/key
 +
 +
* get [https://market.android.com/details?id=stericson.busybox&hl=en busybox]
 +
* Do the update thing if you don't have latest version, follow settings from article
 +
* get [https://market.android.com/details?id=de.schaeuffelhut.android.openvpn.installer&hl=en openvpn installer] and [https://market.android.com/details?id=de.schaeuffelhut.android.openvpn&hl=en openvpn settings]
 +
* I needed to add the tun path  /system/lib/modules/tun.ko in openvpn setting
 +
* Now it connects but doesn't seem to work. The routing table doesn't seem updated, no connection to the interweb trough the vpn, no connection to machines on the 0x20 network.
  
 
=== Client config Wintendo ===
 
=== Client config Wintendo ===
Line 369: Line 397:
 
     cert "C:\\Program Files\\OpenVPN\\easy-rsa\\keys\\0x20-vpn-your_name_here.cert"
 
     cert "C:\\Program Files\\OpenVPN\\easy-rsa\\keys\\0x20-vpn-your_name_here.cert"
 
     key "C:\\Program Files\\OpenVPN\\easy-rsa\\keys\\0x20-vpn-your_name_here.key"
 
     key "C:\\Program Files\\OpenVPN\\easy-rsa\\keys\\0x20-vpn-your_name_here.key"
* start openvpn as admin... click on icon in taskbar ...   
+
* start openvpn as admin... click on icon in taskbar ...Select openvpn_0x20, select connect  
  
'''Important:''' When executing openvpn use administrator permissions (run as administrator). Selecte openvpn_0x20, select connect
+
'''Important:''' When executing openvpn use administrator permissions (run as administrator).
 +
 
 +
=== Client Config Mac ===
 +
* get [http://code.google.com/p/tunnelblick/ Tunnelblick]
 +
* create following config file: ~/Library/Application\ Support/Tunnelblick/Configurations/0x20-vpn.conf and change values in bold
 +
    client
 +
    remote members.0x20.be 1194
 +
    proto udp
 +
    dev tun 
 +
   
 +
    resolv-retry infinite
 +
    nobind
 +
   
 +
    user nobody
 +
    group nogroup
 +
       
 +
    persist-key
 +
    persist-tun
 +
   
 +
    up tap-up-down.sh
 +
    down tap-up-down.sh 
 +
   
 +
    '''ca certs/ca-0x20-cert.pem'''
 +
    '''cert certs/0x20-vpn-<name>.cert'''
 +
    '''key certs/0x20-vpn-<name>.key'''
 +
   
 +
    ns-cert-type server
 +
   
 +
    # If a tls-auth key is used on the server
 +
    # then every client must also have the key.
 +
    ;tls-auth ta.key 1
 +
 
 +
    cipher AES-256-CBC
 +
    comp-lzo
 +
   
 +
    verb 3
 +
    mute 20
 +
* create following configuration script: ~/Library/Application\ Support/Tunnelblick/Configurations/openvpn-tap-up-down.sh
 +
    #!/bin/sh
 +
    #
 +
    # openvpn-tap-up-down.sh
 +
    #
 +
    #
 +
    # A script to be used as an OpenVPN bridged (tap) up/down script on Mac OS X
 +
    # - uses ipconfig to acquire a DHCP lease via the OpenVPN tap interface, and scutil to
 +
    #  incorporate the DHCP-supplied DNS configuration
 +
    #
 +
    # Use in your OpenVPN config file as follows:
 +
    #
 +
    #    up  openvpn-tap-up-down.sh
 +
    #
 +
    # - up: openvpn calls the 'up' script after the tun/tap interface is created, but before the link
 +
    #  to the server is available for use (ditto 'up-delay' at least for UDP)
 +
    #  - on testing w/ openvpn 2.0.5, and tcpdump on the tap interface as soon as it comes up,
 +
    #    packets are queued up on the interface (and not actually sent over the openvpn tunnel)
 +
    #    until *after* this script returns; this makes sense: this script could fail in which
 +
    #    case the connection is invalid
 +
    #    - this means the DHCP acquisition can't complete until after this script exits
 +
    #    - that's not directly a problem as the OS X DHCP client should do everything we need
 +
    #      to make the interface functional, all by itself - *except* for one small thing: as of
 +
    #      OS X 10.4.7 the DHCP-acquired DNS information is not "merged" into the System
 +
    #      Configuration (OS X bug?)
 +
    #      - thus we have a chicken-and-egg situation: we need to manually fixup the DNS config,
 +
    #        but can't until we get the DHCP lease; we won't get the lease until we this script exits
 +
    #      - the solution is to spawn a little "helper" that waits until the lease is acquired,
 +
    #        and then does the DNS fixup
 +
    #
 +
    # - down: the only sensible 'down' action is to release the DHCP lease (as a courtesy to the
 +
    #  DHCP server), alas it's too late to do this *after* the connection has been shutdown (as
 +
    #  of OpenVPN 2.0 there's no "pre-disconnect" script option; note that both 'down' and
 +
    #  'down-pre' are called only after the connection to the server is closed ('down-pre' before
 +
    #  closing the tun/tap device, 'down' after)
 +
    #  - OS X automatically cleans up the System Config keys created from ipconfig, but we need to
 +
    #    manually remove the DNS fixup
 +
    #
 +
    # 2006-09-21    Ben Low    original
 +
    #
 +
   
 +
    if [ -z "$dev" ]; then echo "$0: \$dev not defined, exiting"; exit 1; fi
 +
   
 +
    # relevant script_type values are 'up' or 'down'
 +
    case "$script_type" in
 +
      up)
 +
   
 +
        # bring the interface up and set it to DHCP
 +
        # - System Configuration dynamic store will be automatically updated, with the
 +
        #      State:/Network/Service/DHCP-tap0
 +
        #  data store created.
 +
        # - the ipconfig man page notes that it should only be used for "test and debug" purposes,
 +
        #  and that you're supposed to use the SystemConfiguration APIs to manipulate the network
 +
        #  configuration
 +
        #  - alas, there appears to be no CLI utility other than ipconfig
 +
   
 +
        /usr/sbin/ipconfig set "$dev" DHCP
 +
   
 +
        # spawn our little DNS-fixerupper
 +
        {
 +
            # whilst ipconfig will have created the neccessary Network Service keys, the DNS
 +
            # settings won't actually be used by OS X unless the SupplementalMatchDomains key
 +
            # is added
 +
            # ref. <http://lists.apple.com/archives/Macnetworkprog/2005/Jun/msg00011.html>
 +
            # - is there a way to extract the domains from the SC dictionary and re-insert
 +
            #  as SupplementalMatchDomains? i.e. not requiring the ipconfig domain_name call?
 +
   
 +
            # - wait until we get a lease before extracting the DNS domain name and merging into SC
 +
            # - despite it's name, ipconfig waitall doesn't (but maybe one day it will :-)
 +
            /usr/sbin/ipconfig waitall
 +
   
 +
            # usually takes at least a few seconds to get a DHCP lease
 +
            sleep 3
 +
            n=0
 +
            while [ -z "$domain_name" -a $n -lt 5 ]
 +
            do
 +
                sleep $n
 +
                n=`expr $n + 1`
 +
                domain_name=`/usr/sbin/ipconfig getoption $dev domain_name 2>/dev/null`
 +
            done
 +
   
 +
            if [ "$domain_name" ]; then
 +
            /usr/sbin/scutil <<EOF
 +
    d.init
 +
    get State:/Network/Service/DHCP-$dev/DNS
 +
    d.add SupplementalMatchDomains * $domain_name
 +
    set State:/Network/Service/DHCP-$dev/DNS
 +
    EOF
 +
            fi
 +
   
 +
        } &
 +
   
 +
      ;;
 +
   
 +
      down)
 +
   
 +
        # for completeness...
 +
        if [ `/usr/bin/id -u` -eq 0 ]; then
 +
            /usr/sbin/ipconfig set "$dev" NONE
 +
        fi
 +
   
 +
      ;;
 +
      *) echo "$0: invalid script_type" && exit 1 ;;
 +
    esac
 +
   
 +
    ##### FIN
 +
* Set proper permission on the configuration script: chmod +x ~/Library/Application\ Support/Tunnelblick/Configurations/openvpn-tap-up-down.sh
  
 
== Server members.0x20.be ==
 
== Server members.0x20.be ==
Line 473: Line 644:
 
# sysctl -w net.ipv4.ip_forward=1
 
# sysctl -w net.ipv4.ip_forward=1
 
</pre>
 
</pre>
* NAT:
+
* NAT (added to rc.local):
 
<pre>
 
<pre>
 
# iptables -t nat -A POSTROUTING -s 172.20.200.0/24 -o eth0 -j MASQUERADE
 
# iptables -t nat -A POSTROUTING -s 172.20.200.0/24 -o eth0 -j MASQUERADE
 
</pre>
 
</pre>
* Add route to make 0x20 network (172.22.32.0/24) available over the vpn tunnel:
+
* Add route to make 0x20 network (172.22.32.0/24) available over the vpn tunnel (added to rc.local):
 
<pre>
 
<pre>
 
# route add -net 172.22.32.0 netmask 255.255.255.0 dev vpn-0x20
 
# route add -net 172.22.32.0 netmask 255.255.255.0 dev vpn-0x20
 
</pre>
 
</pre>
  
Setup routing on 0x20-router (soekris):
+
Setup routing on 0x20-router (soekris), added to /etc/rc.local:
 
<pre>
 
<pre>
 
# route add -net 172.20.200.0 netmask 255.255.255.0 dev vpn-members
 
# route add -net 172.20.200.0 netmask 255.255.255.0 dev vpn-members
Line 494: Line 665:
 
remote members.0x20.be                        # Peer-Address, (Dyn)DNS if it's
 
remote members.0x20.be                        # Peer-Address, (Dyn)DNS if it's
 
lport 40002                                    # local port
 
lport 40002                                    # local port
rport 443                                     # remote port
+
rport 1195                                     # remote port
proto tcp-client                               # ...via TCP, use server mode
+
proto udp                               # ...via UDP, use server mode
 
dev-type tun
 
dev-type tun
 
dev vpn-members                                # interfacename, just individual
 
dev vpn-members                                # interfacename, just individual
Line 514: Line 685:
 
<pre>
 
<pre>
 
mode p2p                                      # Peer-to-peer-Mode
 
mode p2p                                      # Peer-to-peer-Mode
remote 83.101.72.80                            # Peer-Address, (Dyn)DNS if it's
+
remote 0x20.dyndns.info                      # Peer-Address, (Dyn)DNS if it's
lport 443                                     # local port
+
lport 1195                                     # local port
 
rport 40002                                    # remote por  
 
rport 40002                                    # remote por  
proto tcp-server                               # ...via TCP, use server mode
+
proto udp                               # ...via UDP, use server mode
 
dev-type tun  
 
dev-type tun  
 
dev vpn-0x20                                  # interfacename, just individual
 
dev vpn-0x20                                  # interfacename, just individual
Line 533: Line 704:
 
ifconfig 172.20.201.1 172.22.32.5              # addressing: 'ifconfig localip remoteip'
 
ifconfig 172.20.201.1 172.22.32.5              # addressing: 'ifconfig localip remoteip'
 
</pre>
 
</pre>
 
== Server ==
 
The virtual network exist out of two parts:
 
1) a point-to-point vpn that connects the big pipe server at the ibbt with the the whitespace network
 
2) a server-client vpn that allows users to
 

Latest revision as of 01:57, 10 November 2011


OpenVPN
WhitespaceLogo.gif
What:
VPN server
Participants:
Jaroslov, Abe, Hans
Locations:
Whitespace
Cornify

Important considerations before use[edit]

Notes

  • The connection is encrypted and controlled by us until it gets on the ibbt server. After that it's public and goes over the network of ibbt/belnet.
  • There is no anonymity implied, public ip will be linked to our vps, the reverse dns even works.
  • Remember to switch off your P2P software because the traffic patterns won't disclose the fact that it's just linux iso's. Also if you want to connect it's your duty to verify your machine isn't r00ted.
  • IBBT T&A: if they receive a complaint, they will shut the server down. I expect no problems here but please be conscious about it and think of your fellow members ;-)

Use cases

  • safer communication in hostile environments (unencrypted hotspots, certain conferences)
  • Direct line onto the local 0x20 network , troll ppl by playing bad music, cause seizures by manipulating the lights, play with local services.

Setup[edit]

An OpenVPN server on members.0x20.be, connected to Belnet, hosted by IBBT. There is also a p2p tunnel to the space to provide connectivity to the 0x20 internal network. Authentication is done with SSL client certificates based on a 0x20 CA. All client certificates signed by the 0x20 CA and with an 'OU=members' are allowed to connect. Future access can be denied by revoking the client certificate and updating the CRL (Certificate Revocation List).

See below for the steps to connect to the VPN server. Further below is the documentation of the server configurations.

Client[edit]

Create a new key[edit]

Linux/windows/Mac OS X:

   $ openssl genrsa -aes256 -out 0x20-vpn-your_name_here.key 2048

Create a Certificate signing request[edit]

  • The bold values need to be correct, case-sensitive!
   $ openssl req -new -key 0x20-vpn-your_name_here.key -out 0x20-vpn-your_name_here.csr
           countryName               = BE
           stateOrProvinceName       = Ghent
           Locality Name             = Whitespace
           organizationName          = 0x20
           organizationalUnitName    = members
           commonName                = your_name_here

Get your certificate signed[edit]

Mail your CSR(certificate signing request) to someone who has access to the 0x20 CA. Best is being physically present in the space.

Sign cert:

   $ openssl ca -in ../0x20-vpn-your_name_here.csr -cert ca-0x20-cert.pem -keyfile private/ca-0x20-key.pem -out 0x20-vpn-your_name_here.cert -config ./openssl.cnf

Client config Linux[edit]

  • apt-get install openvpn
  • create following config file: /etc/openvpn/0x20-vpn.conf and change values in bold
   client
   remote members.0x20.be 1194
   proto udp 
   dev tun  
   
   resolv-retry infinite
   nobind
   
   user nobody
   group nogroup
       
   persist-key
   persist-tun
   
   ca certs/ca-0x20-cert.pem
   cert certs/0x20-vpn-<name>.cert
   key certs/0x20-vpn-<name>.key
   
   ns-cert-type server
   
   # If a tls-auth key is used on the server
   # then every client must also have the key.
   ;tls-auth ta.key 1
  
   cipher AES-256-CBC
   comp-lzo
   
   verb 3
   mute 20

Client config android[edit]

Following : http://vpnblog.info/android-openvpn-strongvpn.html

Also assuming you've set it up in linux/windows and have the three files ca/cert/key

  • get busybox
  • Do the update thing if you don't have latest version, follow settings from article
  • get openvpn installer and openvpn settings
  • I needed to add the tun path /system/lib/modules/tun.ko in openvpn setting
  • Now it connects but doesn't seem to work. The routing table doesn't seem updated, no connection to the interweb trough the vpn, no connection to machines on the 0x20 network.

Client config Wintendo[edit]

  • Get openvpn for windows here version OpenVPN 2.2.1 or higher
  • Save this content to this filename C:\Program Files\OpenVPN\config\Openvpn_0x20.ovpn
client
remote members.0x20.be 1194
proto udp 
dev tun  

resolv-retry infinite
nobind

user nobody
group nogroup
 
persist-key
persist-tun

#change the paths as needed.
ca "C:\\Program Files\\OpenVPN\\easy-rsa\\keys\\ca-0x20-cert.pem"
cert "C:\\Program Files\\OpenVPN\\easy-rsa\\keys\\0x20-vpn-your_name_here.cert"
key "C:\\Program Files\\OpenVPN\\easy-rsa\\keys\\0x20-vpn-your_name_here.key"


ns-cert-type server

# If a tls-auth key is used on the server
# then every client must also have the key.
;tls-auth ta.key 1
  
cipher AES-256-CBC
comp-lzo

verb 3
mute 20
  • open cmd with administrator privileges (start menu -> cmd -> run as admin)
  • cd Program Files\OpenVPN\easy-rsa
  • give command init-config.bat
  • Save following content as C:\Progra~1\OpenVPN\easy-rsa\openssl.cnf
#
# OpenSSL example configuration file.
# This is mostly being used for generation of certificate requests.
#

# This definition stops the following lines choking if HOME isn't
# defined.
HOME			= .
RANDFILE		= $ENV::HOME/.rnd

# Extra OBJECT IDENTIFIER info:
#oid_file		= $ENV::HOME/.oid
oid_section		= new_oids

# To use this configuration file with the "-extfile" option of the
# "openssl x509" utility, name here the section containing the
# X.509v3 extensions to use:
# extensions		= 
# (Alternatively, use a configuration file that has only
# X.509v3 extensions in its main [= default] section.)

[ new_oids ]

# We can add new OIDs in here for use by 'ca' and 'req'.
# Add a simple OID like this:
# testoid1=1.2.3.4
# Or use config file substitution like this:
# testoid2=${testoid1}.5.6

####################################################################
[ ca ]
default_ca	= CA_default		# The default ca section

####################################################################
[ CA_default ]

dir		= C:/user/local/ssl		# Where everything is kept
certs		= $dir			# Where the issued certs are kept
crl_dir		= $dir			# Where the issued crl are kept
database	= $dir/index.txt	# database index file.
new_certs_dir	= $dir			# default place for new certs.

certificate	= $dir/ca.crt	 	# The CA certificate
serial		= $dir/serial 		# The current serial number
crl		= $dir/crl.pem 		# The current CRL
private_key	= $dir/ca.key	 	# The private key
RANDFILE	= $dir/.rand		# private random number file

x509_extensions	= usr_cert		# The extentions to add to the cert

# Extensions to add to a CRL. Note: Netscape communicator chokes on V2 CRLs
# so this is commented out by default to leave a V1 CRL.
# crl_extensions	= crl_ext

default_days	= 3650			# how long to certify for
default_crl_days= 30			# how long before next CRL
default_md	= md5			# which md to use.
preserve	= no			# keep passed DN ordering

# A few difference way of specifying how similar the request should look
# For type CA, the listed attributes must be the same, and the optional
# and supplied fields are just that :-)
policy		= policy_match

# For the CA policy
[ policy_match ]
countryName		= match
stateOrProvinceName	= match
organizationName	= match
organizationalUnitName	= optional
commonName		= supplied
emailAddress		= optional

# For the 'anything' policy
# At this point in time, you must list all acceptable 'object'
# types.
[ policy_anything ]
countryName		= optional
stateOrProvinceName	= optional
localityName		= optional
organizationName	= optional
organizationalUnitName	= optional
commonName		= supplied
emailAddress		= optional

####################################################################
[ req ]
default_bits		= 2048
default_keyfile 	= privkey.pem
distinguished_name	= req_distinguished_name
attributes		= req_attributes
x509_extensions	= v3_ca	# The extentions to add to the self signed cert

# Passwords for private keys if not present they will be prompted for
# input_password = secret
# output_password = secret

# This sets a mask for permitted string types. There are several options. 
# default: PrintableString, T61String, BMPString.
# pkix	 : PrintableString, BMPString.
# utf8only: only UTF8Strings.
# nombstr : PrintableString, T61String (no BMPStrings or UTF8Strings).
# MASK:XXXX a literal mask value.
# WARNING: current versions of Netscape crash on BMPStrings or UTF8Strings
# so use this option with caution!
string_mask = nombstr

# req_extensions = v3_req # The extensions to add to a certificate request

[ req_distinguished_name ]
countryName			= Country Name (2 letter code)
countryName_default		= BE
countryName_min			= 2
countryName_max			= 2

stateOrProvinceName		= State or Province Name (full name)
stateOrProvinceName_default	= Ghent

localityName			= Locality Name (eg, city)
localityName_default		= Whitespace

0.organizationName		= Organization Name (eg, company)
0.organizationName_default	= 0x20

# we can do this but it is not needed normally :-)
#1.organizationName		= Second Organization Name (eg, company)
#1.organizationName_default	= World Wide Web Pty Ltd

organizationalUnitName		= Organizational Unit Name (eg, section)
organizationalUnitName_default	= members

commonName			= Common Name (eg, your name or your server\'s hostname)
commonName_max			= 64

emailAddress			= Email Address
#emailAddress_default		= $ENV::KEY_EMAIL
emailAddress_max		= 40

# SET-ex3			= SET extension number 3

[ req_attributes ]
challengePassword		= A challenge password
challengePassword_min		= 4
challengePassword_max		= 20

unstructuredName		= An optional company name

[ usr_cert ]

# These extensions are added when 'ca' signs a request.

# This goes against PKIX guidelines but some CAs do it and some software
# requires this to avoid interpreting an end user certificate as a CA.

basicConstraints=CA:FALSE

# Here are some examples of the usage of nsCertType. If it is omitted
# the certificate can be used for anything *except* object signing.

# This is OK for an SSL server.
# nsCertType			= server

# For an object signing certificate this would be used.
# nsCertType = objsign

# For normal client use this is typical
# nsCertType = client, email

# and for everything including object signing:
# nsCertType = client, email, objsign

# This is typical in keyUsage for a client certificate.
# keyUsage = nonRepudiation, digitalSignature, keyEncipherment

# This will be displayed in Netscape's comment listbox.
nsComment			= "OpenSSL Generated Certificate"

# PKIX recommendations harmless if included in all certificates.
subjectKeyIdentifier=hash
authorityKeyIdentifier=keyid,issuer:always

# This stuff is for subjectAltName and issuerAltname.
# Import the email address.
# subjectAltName=email:copy

# Copy subject details
# issuerAltName=issuer:copy

#nsCaRevocationUrl		= http://www.domain.dom/ca-crl.pem
#nsBaseUrl
#nsRevocationUrl
#nsRenewalUrl
#nsCaPolicyUrl
#nsSslServerName

[ server ]

# JY ADDED -- Make a cert with nsCertType set to "server"
basicConstraints=CA:FALSE
nsCertType			= server
nsComment			= "OpenSSL Generated Server Certificate"
subjectKeyIdentifier=hash
authorityKeyIdentifier=keyid,issuer:always

[ v3_req ]

# Extensions to add to a certificate request

basicConstraints = CA:FALSE
keyUsage = nonRepudiation, digitalSignature, keyEncipherment

[ v3_ca ]


# Extensions for a typical CA


# PKIX recommendation.

subjectKeyIdentifier=hash

authorityKeyIdentifier=keyid:always,issuer:always

# This is what PKIX recommends but some broken software chokes on critical
# extensions.
#basicConstraints = critical,CA:true
# So we do this instead.
basicConstraints = CA:true

# Key usage: this is typical for a CA certificate. However since it will
# prevent it being used as an test self-signed certificate it is best
# left out by default.
# keyUsage = cRLSign, keyCertSign

# Some might want this also
# nsCertType = sslCA, emailCA

# Include email address in subject alt name: another PKIX recommendation
# subjectAltName=email:copy
# Copy issuer details
# issuerAltName=issuer:copy

# DER hex encoding of an extension: beware experts only!
# obj=DER:02:03
# Where 'obj' is a standard or added object
# You can even override a supported extension:
# basicConstraints= critical, DER:30:03:01:01:FF

[ crl_ext ]

# CRL extensions.
# Only issuerAltName and authorityKeyIdentifier make any sense in a CRL.

# issuerAltName=issuer:copy
authorityKeyIdentifier=keyid:always,issuer:always
  • Navigate to a dir where you have write permissions
  • command : openssl genrsa -aes256 -out 0x20-vpn-your_name_here.key 2048
  • command : openssl req -new -key 0x20-vpn-your_name_here.key -out 0x20-vpn-your_name_here.csr -config C:\Progra~1\OpenVPN\easy-rsa\openssl.cnf
  • Answer the questions in accordance
    • countryName = BE
    • stateOrProvinceName = Ghent
    • organizationName = 0x20
    • organizationalUnitName = members
    • commonName = your_name_here
  • Send the csr to jaroslav
  • save the three files at the right place
   ca "C:\\Program Files\\OpenVPN\\easy-rsa\\keys\\ca-0x20-cert.pem"
   cert "C:\\Program Files\\OpenVPN\\easy-rsa\\keys\\0x20-vpn-your_name_here.cert"
   key "C:\\Program Files\\OpenVPN\\easy-rsa\\keys\\0x20-vpn-your_name_here.key"
  • start openvpn as admin... click on icon in taskbar ...Select openvpn_0x20, select connect

Important: When executing openvpn use administrator permissions (run as administrator).

Client Config Mac[edit]

  • get Tunnelblick
  • create following config file: ~/Library/Application\ Support/Tunnelblick/Configurations/0x20-vpn.conf and change values in bold
   client
   remote members.0x20.be 1194
   proto udp 
   dev tun  
   
   resolv-retry infinite
   nobind
   
   user nobody
   group nogroup
       
   persist-key
   persist-tun
   
   up tap-up-down.sh
   down tap-up-down.sh   
   
   ca certs/ca-0x20-cert.pem
   cert certs/0x20-vpn-<name>.cert
   key certs/0x20-vpn-<name>.key
   
   ns-cert-type server
   
   # If a tls-auth key is used on the server
   # then every client must also have the key.
   ;tls-auth ta.key 1
  
   cipher AES-256-CBC
   comp-lzo
   
   verb 3
   mute 20
  • create following configuration script: ~/Library/Application\ Support/Tunnelblick/Configurations/openvpn-tap-up-down.sh
   #!/bin/sh
   #
   # openvpn-tap-up-down.sh
   #
   #
   # A script to be used as an OpenVPN bridged (tap) up/down script on Mac OS X
   # - uses ipconfig to acquire a DHCP lease via the OpenVPN tap interface, and scutil to
   #  incorporate the DHCP-supplied DNS configuration
   #
   # Use in your OpenVPN config file as follows:
   #
   #    up  openvpn-tap-up-down.sh
   #
   # - up: openvpn calls the 'up' script after the tun/tap interface is created, but before the link
   #   to the server is available for use (ditto 'up-delay' at least for UDP)
   #   - on testing w/ openvpn 2.0.5, and tcpdump on the tap interface as soon as it comes up,
   #     packets are queued up on the interface (and not actually sent over the openvpn tunnel)
   #     until *after* this script returns; this makes sense: this script could fail in which
   #     case the connection is invalid
   #     - this means the DHCP acquisition can't complete until after this script exits
   #     - that's not directly a problem as the OS X DHCP client should do everything we need
   #       to make the interface functional, all by itself - *except* for one small thing: as of
   #       OS X 10.4.7 the DHCP-acquired DNS information is not "merged" into the System
   #       Configuration (OS X bug?)
   #       - thus we have a chicken-and-egg situation: we need to manually fixup the DNS config,
   #         but can't until we get the DHCP lease; we won't get the lease until we this script exits
   #       - the solution is to spawn a little "helper" that waits until the lease is acquired,
   #         and then does the DNS fixup
   #
   # - down: the only sensible 'down' action is to release the DHCP lease (as a courtesy to the
   #   DHCP server), alas it's too late to do this *after* the connection has been shutdown (as
   #   of OpenVPN 2.0 there's no "pre-disconnect" script option; note that both 'down' and
   #   'down-pre' are called only after the connection to the server is closed ('down-pre' before
   #   closing the tun/tap device, 'down' after)
   #   - OS X automatically cleans up the System Config keys created from ipconfig, but we need to
   #     manually remove the DNS fixup
   #
   # 2006-09-21    Ben Low    original
   #
   
   if [ -z "$dev" ]; then echo "$0: \$dev not defined, exiting"; exit 1; fi
   
   # relevant script_type values are 'up' or 'down'
   case "$script_type" in
      up)
   
        # bring the interface up and set it to DHCP
        # - System Configuration dynamic store will be automatically updated, with the
        #       State:/Network/Service/DHCP-tap0
        #   data store created.
        # - the ipconfig man page notes that it should only be used for "test and debug" purposes,
        #   and that you're supposed to use the SystemConfiguration APIs to manipulate the network
        #   configuration
        #   - alas, there appears to be no CLI utility other than ipconfig
   
        /usr/sbin/ipconfig set "$dev" DHCP
   
        # spawn our little DNS-fixerupper
        {
            # whilst ipconfig will have created the neccessary Network Service keys, the DNS
            # settings won't actually be used by OS X unless the SupplementalMatchDomains key
            # is added
            # ref. <http://lists.apple.com/archives/Macnetworkprog/2005/Jun/msg00011.html>
            # - is there a way to extract the domains from the SC dictionary and re-insert
            #   as SupplementalMatchDomains? i.e. not requiring the ipconfig domain_name call?
   
            # - wait until we get a lease before extracting the DNS domain name and merging into SC
            # - despite it's name, ipconfig waitall doesn't (but maybe one day it will :-)
            /usr/sbin/ipconfig waitall
   
            # usually takes at least a few seconds to get a DHCP lease
            sleep 3
            n=0
            while [ -z "$domain_name" -a $n -lt 5 ]
            do
                sleep $n
                n=`expr $n + 1`
                domain_name=`/usr/sbin/ipconfig getoption $dev domain_name 2>/dev/null`
            done
   
            if [ "$domain_name" ]; then
            /usr/sbin/scutil <<EOF
   d.init
   get State:/Network/Service/DHCP-$dev/DNS
   d.add SupplementalMatchDomains * $domain_name
   set State:/Network/Service/DHCP-$dev/DNS
   EOF
            fi
   
        } &
   
      ;;
   
      down)
   
        # for completeness...
        if [ `/usr/bin/id -u` -eq 0 ]; then
            /usr/sbin/ipconfig set "$dev" NONE
        fi
   
      ;;
      *) echo "$0: invalid script_type" && exit 1 ;;
   esac
   
   ##### FIN
  • Set proper permission on the configuration script: chmod +x ~/Library/Application\ Support/Tunnelblick/Configurations/openvpn-tap-up-down.sh

Server members.0x20.be[edit]

  • server mode
  • uses 0x20 CA
  • only accepts client certificates with OU=members
  • uses crl
  • range 172.20.200.0/24

OpenVPN config[edit]

  • /etc/openvpn/public.conf :
mode server
lport 1194
proto udp 
dev-type tun 
dev vpn-public

ca certs/ca-0x20-cert.pem
crl-verify certs/ca-0x20-crl.pem
cert certs/0x20-members-vpn.cert
key certs/0x20-members-vpn.key # This file should be kept secret
dh certs/dh2048.pem

tls-verify "./certs/verify-ou members"

server 172.20.200.0 255.255.255.0
ifconfig-pool-persist ipp.txt
push "route 172.22.32.0 255.255.255.0"
push "redirect-gateway def1"

comp-lzo
cipher AES-256-CBC

user nobody
group nogroup

status /var/log/openvpn-status-public.log
log-append /var/log/openvpn-public.log
verb 2
mute 20
  • /etc/openvpn/certs/verify-ou :
#!/usr/bin/perl

# verify-cn -- a sample OpenVPN tls-verify script
#
# Return 0 if cn matches the common name component of
# X509_NAME_oneline, 1 otherwise.
#
# For example in OpenVPN, you could use the directive:
#
#   tls-verify "./verify-cn Test-Client"
#
# This would cause the connection to be dropped unless
# the client common name is "Test-Client"

die "usage: verify-cn cn certificate_depth X509_NAME_oneline" if (@ARGV != 3); 

# Parse out arguments:
#   ou    -- The common name which the client is required to have,
#            taken from the argument to the tls-verify directive
#            in the OpenVPN config file.
#   depth -- The current certificate chain depth.  In a typical
#            bi-level chain, the root certificate will be at level
#            1 and the client certificate will be at level 0.
#            This script will be called separately for each level.
#   x509  -- the X509 subject string as extracted by OpenVPN from
#            the client's provided certificate.
($ou, $depth, $x509) = @ARGV;

if ($depth == 0) {
    # If depth is zero, we know that this is the final
    # certificate in the chain (i.e. the client certificate),
    # and the one we are interested in examining.
    # If so, parse out the common name substring in
    # the X509 subject string.

    if ($x509 =~ /\/OU=([^\/]+)/) {
    # Accept the connection if the X509 common name
    # string matches the passed cn argument.
    if ($ou eq $1) {
        exit 0;
    }   
    }   

    # Authentication failed -- Either we could not parse
    # the X509 subject string, or the common name in the
    # subject string didn't match the passed cn argument.
    exit 1;
}
# If depth is nonzero, tell OpenVPN to continue processing
# the certificate chain.
exit 0;

Network config[edit]

  • Enable IP forwarding:
# sysctl -w net.ipv4.ip_forward=1
  • NAT (added to rc.local):
# iptables -t nat -A POSTROUTING -s 172.20.200.0/24 -o eth0 -j MASQUERADE
  • Add route to make 0x20 network (172.22.32.0/24) available over the vpn tunnel (added to rc.local):
# route add -net 172.22.32.0 netmask 255.255.255.0 dev vpn-0x20

Setup routing on 0x20-router (soekris), added to /etc/rc.local:

# route add -net 172.20.200.0 netmask 255.255.255.0 dev vpn-members

Server 0x20 <-> IBBT[edit]

A P2P tunnel between 0x20 and IBBT.

  • 0x20/soekris config, /etc/openvpn/members.conf :
mode p2p                                       # Peer-to-peer-Mode
remote members.0x20.be                         # Peer-Address, (Dyn)DNS if it's
lport 40002                                    # local port
rport 1195                                      # remote port
proto udp                               # ...via UDP, use server mode
dev-type tun
dev vpn-members                                # interfacename, just individual
#tun-ipv6                                      # we want to use ipv6
comp-lzo                                       # compression
#cd /usr/local/etc/openvpn                     # here lays the key
secret members.key                             # the filename of the key
user nobody                                    # username under which openvpn
group nogroup                                  # ...group
persist-key                                    # on interruption, please keep
persist-tun                                    # on interruption, please keep
status /var/log/openvpn-status-members.log
log-append /var/log/openvpn-members.log
verb 2                                        # Verbose!
ifconfig 172.22.32.5 172.20.201.1             # addressing: 'ifconfig localip remoteip'
  • members.0x20.be config, /etc/openvpn/0x20.conf :
mode p2p                                       # Peer-to-peer-Mode
remote  0x20.dyndns.info                       # Peer-Address, (Dyn)DNS if it's
lport 1195                                      # local port
rport 40002                                    # remote por 
proto udp                               # ...via UDP, use server mode
dev-type tun 
dev vpn-0x20                                   # interfacename, just individual
#tun-ipv6                                      # we want to use ipv6
comp-lzo                                       # compression
#cd /usr/local/etc/openvpn                     # here lays the key 
secret 0x20.key                                # the filename of the key
user nobody                                    # username under which openvpn
group nogroup                                  # ...group
persist-key                                    # on interruption, please keep
persist-tun                                    # on interruption, please keep
status /var/log/openvpn-status-0x20.log
log-append /var/log/openvpn-0x20.log
verb 2                                         # Verbose!
ifconfig 172.20.201.1 172.22.32.5              # addressing: 'ifconfig localip remoteip'