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<!--There are three wireless networks on campus. One network, called VT-Wireless, encrypts all traffic and is secured with [[EAP-TLS]] or PEAP-MSCHAPv2. A second network, CONNECTtoVT-Wireless, is an unencrypted, captive portal wireless network designed to set up connecting to VT-Wireless without offering Internet access. Due to user issues faced during deployment, CONNECTtoVT-Wireless began offering captive portal access to VT users.-->On campus, there are 2 wireless networks. '''Eduroam''' is the preferred method, which uses PEAP-MSCHAPv2 to authenticate to the RADIUS server, while the second SSID, '''VirginiaTech''', provides a captive-portaland allows for guest account creation.

As of January 2015 the [https://www.computing.vt.edu/content/eduroam preferred method] of wireless access at Virginia Tech is through the [https://eduroam.org/ Eduroam] network. Eduroam is a secure wireless access service that was developed for the use of research and educational institutions. One of the advantages of the Eduroam network over the VT-Wireless network is that you will be able to connect to the Internet at any participating institution using your Virginia Tech credentials. The Eduroam-US site provides a [https://www.eduroam.us/technical_overview technical overview] of how the network authenticates you to the Virginia Tech RADIUS servers.

===Obtaining the Certificate PinningChain=== The certificate presented by the RADIUS server is chained as such: * GlobalSign Root CA - R3 ** Trusted Root CA SHA256 G2*** Virginia Tech Global Qualified Server CA**** eduroam.nis.vt.edu Below is where to obtain each of these, along with some metadata. The filenames are arbitrary, but will be used for the rest of this article. For every certificate (''especially'' the root, the signature chain helps with the rest), consider where you are obtaining it from and how much trust that you are getting what you think you are. You will probably want the PEM formatted certificate, if you have the option. ====GlobalSign Root CA - R3==== ''Filename:'' GlobalSign_Root_CA_-_R3.pem ''Subject:'' OU = GlobalSign Root CA - R3, O = GlobalSign, CN = GlobalSign This is a common root CA and should have shipped with your OS. It is likely located in <code>/etc/ssl/certs/GlobalSign_Root_CA_-_R3.pem</code>. If you are unable to locate it in your OS, you can get it directly from [https://2029.globalsign.com/ GlobalSign]. (This page seems to not be loading correctly at the moment. [https://support.globalsign.com/customer/en/portal/articles/1426602-globalsign-root-certificates Here] is the parent page.) ====Trusted Root CA SHA256 G2==== ''Filename:'' TrustedRootCASHA256G2.pem ''Subject:'' C = BE, OU = Trusted Root, O = GlobalSign nv-sa, CN = Trusted Root CA SHA256 G2 This is an intermediate certificate, again issued by GlobalSign. You can get it directly from GlobalSign [https://support.globalsign.com/customer/portal/articles/1211591-trusted-root-intermediate-certificates here]. ====Virginia Tech Global Qualified Server CA==== ''Filename:'' VirginiaTechGlobalQualifiedServerCA.pem ''Subject:'' C = US, ST = Virginia, L = Blacksburg, OU = Global Qualified Server CA, O = Virginia Polytechnic Institute and State University, CN = Virginia Tech Global Qualified Server CA This can be obtained from the Virginia Tech PKI [http://www.pki.vt.edu/developer/rootca.html#globalqualifiedserver website]. This website is only available from VT IP addresses (including VPN). Although certificates higher in the chain are also provided here, the page does ''not'' support https. '''''DO NOT''''' get your root CA here. ====eduroam.nis.vt.edu==== ''Filename:'' eduroam.nis.vt.edu.crt

Due to vulnerabilities in the MSCHAPv2 protocol that allow the protocol to be cracked quickly with a 100% success rate<ref>[https://www.cloudcracker.com/blog/2012/07/29/cracking-ms-chap-v2/ Cracking MS-CHAPv2]</ref>, it is ''absolutely criticalSubject:'' that the RADIUS server certificate be validated properly before attempting authentication. UnfortunatelyC = US, VT has deprecated a much stronger authentication methodST = Virginia, [[EAP-TLS]]L = Blacksburg, O = Virginia Polytechnic Institute and as suchState University, network certificates are no longer an optionCN = eduroam.nis.vt.edu

Where possible, we opt This can be obtained from the [https://apps.pki.vt.edu/ca-manager/search VTCA Certificate Manager]. This requires PID login. Search for the highest level of verification "eduroam.nis.vt.edu". '''Note''': As of 2017 June 19, there will be 2 results, due to some internal testing. Download the certificate: manually pinning with the hash of the certificate we expect to be presentedserial 3699307517ED7E8B. The canonical form of the hash used by many network managers certificate with serial 7A083CC134D0303D is the SHA256 hash of the DER encoding of the certificate''incorrect''.

In order to generate ===Validating the certificate hash, download the certificate by clicking the "Download" link on the [https://ash.eprov.seti.vt.edu/EJBCAWebRequest/certSearch?cmd=search&keyword=VT-Wireless Certificate Search for VT-Wireless] (Unfortunately this site is only available to Virginia Tech IPs)=

Validate that <ol><li> Obtain ''all'' certificates in the downloaded certificate is chain ''in fact signed by PEM format'' </li><li> Concatenate the (Now Obsolete) [httpsnon-leaf certificates in to a single file:</li><pre>$ cat GlobalSign_Root_CA_-_R3.pem TrustedRootCASHA256G2.pem VirginiaTechGlobalQualifiedServerCA.pem >> ca.pem</pre><li> Verify the certificates are signed correctly </secureli><pre>$ openssl verify -verbose -purpose sslserver -CAfile ca.pem eduroam.hostingnis.vt.edu/www.pkicrteduroam.nis.vt.edu.crt: OK</developerpre><li> For at least the root and leaf certificates, verify the subject (compare to above) </rootca.html#globalserver Virginia Tech Global Server CA] chain. You will first need to download ''all'' certificates li><pre>$ openssl x509 -in the "CA: Virginia_Tech_Global_Server_CA" chain and concatenate them.file_of_cert_you_want_to_check -noout -subject</pre></ol>

$ cat GlobalSignRootCADue to vulnerabilities in the MSCHAPv2 protocol that allow the protocol to be cracked quickly with a 100% success rate<ref>[https://web.pem GlobalSignRootSignPartnersCAarchive.pem VirginiaTechGlobalRootCA.pem VirginiaTechGlobalServerCAorg/web/20160316174007/https://www.pem >> cacloudcracker.pem $ openssl verify com/blog/2012/07/29/cracking-verbose ms-purpose sslserver chap-CAfile cav2/]</ref>, it is ''absolutely critical'' that the RADIUS server certificate be validated properly before attempting authentication.pem VT-WirelessWhere possible, we opt for the highest level of verification of the certificate: manually pinning the hash of the certificate we expect to be presented.cns.vt.edu.crt VT-WirelessThe canonical form of the hash used by many network managers is the SHA256 hash of the DER encoding of the certificate.cns.vt.edu.crt: OK

Then Validate the certificate (see above) then generate the sha256 hash:

$ openssl x509 -in VT-Wirelesseduroam.cnsnis.vt.edu.crt -outform der | sha256sum 216c5f2568c6e84860b12535efe93500623ccee999306b84260f951bcbd57b1a 9b5163a3360f07b2dce2fd1e958c541687cf4c5360bb8adc87fa821c1c969910 -

'''Note:''' As we are pinning the certificate instead of relying on a PKI, when CNS NI&S rotates the certificates being used(at least every 2 years), the configuration will need to be updated to match the new certificate.

* In your the list of wireless configuration programnetworks, select "eduroam".Set the following options: * Choose Wi-Fi security: WPA & WPA2 Enterprise* Authentication: Protected EAP (PEAP as the EAP type.)* Choose MSCHAPv2 as the authentication methodAnonymous identity: anonymous@vt.edu* Use PID@Domain: nis.vt.edu and network passphrase as your login credentials* CA certificate: Select <code>/path/to/GlobalSign_Root_CA_-_R3.pem</code> via the file picker* PEAP version: Automatic* Inner authentication: MSCHAPv2* Use anonymousUsername: PID@vt.edu as your Anonymous Identity* '''TODOPassword: YOUR_NETWORK_PASSWORD [[File:''' Certificate verification (Warning, until certificate verification is added, it is ''not'' recommended that you use this method of accessing the networkNm settings.)png]]

#alternately, if you can use this line below, but it is less secure than pinning prefer to dynamically validate the cert!certificate by its cryptographic attributes ca_cert="/path/to/GlobalSign_Root_CA_-_R3.pem" domain_match="VT-Wirelesseduroam.cnsnis.vt.edu"

On [[OpenBSD]], the process is a little more complicated:  # ifconfig wlan0 nwid edoroam wpa wpaakms 802.1x up # /usr/local/sbin/wpa_supplicant -B -i wlan0 -c /etc/wpa_supplicant.conf # dhclient wlan0 # ifconfig iwm0 inet6 autoconf Alternate config options, besides domain_match and ca_cert are as follows (obviously not correct):

domain_suffix_match="cnsnis.vt.edu"

More thourough thorough documentation is available at [https://w1.fi/cgit/hostap/plain/wpa_supplicant/wpa_supplicant.conf]

'domain_match="VT-Wirelesseduroam.cnsnis.vt.edu"'

Eduroam eduroam at Virginia Tech is free for:* VT affiliates with VT-Wireless wireless entitlements (includes students) access and network passwords

* Your wifi probes identify The unencrypted portion of your authentication optionally identifies you as an eduroam user, "anonymous@vt.edu" rather than a VT affiliaterevealing your PID

The main disadvantage is that ===Does eduroam support EAP-TLS?===Currently, the Virginia Tech's eduroam implementation does RADIUS servers are not appear to support the deprecated [[configured for EAP-TLS]] system, while VT-Wireless does (as of February 2015).