As of reSIProcate 1.8, the repro proxy supports Mutual (client) TLS authentication.
This means various things:
- external users can be trusted based on the client certificate they present
- local users can be trusted based on the client certificate they present
- this works with or without a challenge password: you can still demand the local user to pass DIGEST authentication, or you can turn off DIGEST authentication and just rely on the client certificate
Using it in practice - with Jitsi
Jitsi is an excellent, free and open source softphone. It has support for mutual TLS authentication.
This guide explains how to use that feature with repro
- Require repro v1.8.2 or greater
- Require Jitsi build 3912 or later (tested with 4142, the nightly build from 31 July 2012)
Other comments about the environment where this was tested:
- Jitsi on a Debian 6.0 (squeeze, amd64) system with Oracle JRE 1.6.24
- repro on a Debian 7.0 (wheezy pre-release, i386)
- Free 4096 bit RSA certificates from [] used on both client and server
- Normal CN certificates were tested (without subjectAltName or other extensions - that is for another day)
Setup the repro server
- Install the latest Debian 7.0 wheezy build
- Install the repro package:
# apt-get update # apt-get install repro openssl
- Create server certificates (note we are giving examples for pocock.com.au - insert your own domain instead)
# openssl genrsa -out /etc/repro/ssl/domain_key_pocock.com.au.pem 4096 # chmod 0640 /etc/repro/ssl/domain_key_pocock.com.au.pem # chgrp repro /etc/repro/ssl/domain_key_pocock.com.au.pem # openssl req -new -key /etc/repro/ssl/domain_key_pocock.com.au.pem -out /etc/repro/ssl/pocock.com.au.csr -subj '/CN=pocock.com.au' # cat /etc/repro/ssl/pocock.com.au.csr
- Go to the CACert.org certificate request web form. Cut and paste the contents of the CSR file (the output of the cat command)
- The CA will now give you a certificate. Install it on the repro server:
# cat > /etc/repro/ssl/domain_cert_pocock.com.au.pem << EOF -----BEGIN CERTIFICATE----- MIIF5zCCA8+gAwIBAgIDAQKKMA0GCSqGSIb3DQEBBQUAMFQxFDASBgNVBAoTC0NB Y2VydCBJbmMuMR4wHAYDVQQLExVodHRwOi8vd3d3LkNBY2VydC5vcmcxHDAaBgNV BAMTE0NBY2VydCBDbGFzcyAzIFJvb3QwHhcNMTIwODAxMTQzOTA3WhcNMTQwODAx . . . vcx9+LYSwVLCr33NkDx9zqBn3Qp2ZcaUxOdSo/QxdnE2Wj7J06D309RuDRCxZA7E cvfc3qE1Q0ESbEOAmN+ZYHhCHZjKe3jNlxED -----END CERTIFICATE----- EOF
- Now edit the repro config file, /etc/repro/repro.config
# vi /etc/repro/repro.config
- Here is a sample of the config settings that you change from defaults:
IPAddress = 188.8.131.52 UDPPort = 0 TCPPort = 0 TLSPort = 5061 DTLSPort = 0 TLSDomainName = pocock.com.au TLSClientVerification = Mandatory TLSUseEmailAsSIP = true Transport1Interface = 184.108.40.206:5061 Transport1Type = TLS Transport1TlsDomain = pocock.com.au Transport1TlsClientVerification = Mandatory Transport1RecordRouteUri = sip:pocock.com.au;transport=TLS HttpAdminPassword = admin RecordRouteUri = sip:pocock.com.au;transport=tls ForceRecordRouting = true EnumSuffixes = e164.arpa, sip5060.net, e164.org DisableOutbound = false OutboundVersion = 5626 EnableFlowTokens = false ClientNatDetectionMode = DISABLED FlowTimer = 0 EnableCertificateAuthenticator = True DisableAuth = true
- Things you MUST change in the sample config file above:
- all instances of the domain pocock.com.au should be replaced with your domain
- all instances of the IP address 220.127.116.11 should be replaced with your IP address
- all the passwords (HttpAdminPassword)
- Notice that UDP and TCP ports are 0 to disable them --- when you rely on TLS authentication, you don't want non-TLS users to connect.
- Now you can start the proxy
# /etc/init.d/repro start
Getting a client certificate for Jitsi
- An email certificate is sufficient - it does not need to have a dedicated SIP extension in the certificate
- The email address can be in the Common Name (that is how it was for this test) - repro will accept email addresses in 'subjectAltName too
- You typically want to create the keystore on the machine where you will run Jitsi (or create it on another machine and then copy it to the Jitsi machine)
- Generate the keypair and the certificate request (CSR) for the CA, set a password (we use mysecret in these examples):
$ keytool -genkey -alias jitsi1 -keyalg RSA -keysize 4096 -keystore ~/.jitsi.keytool -dname 'CNemail@example.com'
Enter keystore password: Re-enter new password: Enter key password for <jitsi1> (RETURN if same as keystore password):
$ keytool -certreq -alias jitsi1 -file /tmp/jitsi1.csr -keystore ~/.jitsi.keytool -storepass mysecret $ cat /tmp/jitsi1.csr -----BEGIN NEW CERTIFICATE REQUEST----- MIIEZDCCAkwCAQAwHzEdMBsGA1UEAwwUZGFuaWVsQHBvY29jay5jb20uYXUwggIiMA0GCSqGSIb3 DQEBAQUAA4ICDwAwggIKAoICAQC/ySJt3ZNulDnWG7MtrE+Y6Rkl6ln/ovdefxFdoaBSkg4Bqg8K . . . cfsbPXSEcdZTYKzPaQpTtkCeWMRKh5R4M61IOd40tANhVbZbf32sZlAeRos7 -----END NEW CERTIFICATE REQUEST-----
- Log in to CAcert.org. Follow the link to create a Client certificate. Cut and paste the certificate request text into the CAcert.org web form.
- CACert.org will give you a certificate, put it on the Jitsi machine in a file called /tmp/jitsi1.crt:
# cat > /tmp/jitsi1.crt << EOF -----BEGIN CERTIFICATE----- MIIF5zCCA8+gAwIBAgIDAQKKMA0GCSqGSIb3DQEBBQUAMFQxFDASBgNVBAoTC0NB Y2VydCBJbmMuMR4wHAYDVQQLExVodHRwOi8vd3d3LkNBY2VydC5vcmcxHDAaBgNV BAMTE0NBY2VydCBDbGFzcyAzIFJvb3QwHhcNMTIwODAxMTQzOTA3WhcNMTQwODAx . . . vcx9+LYSwVLCr33NkDx9zqBn3Qp2ZcaUxOdSo/QxdnE2Wj7J06D309RuDRCxZA7E cvfc3qE1Q0ESbEOAmN+ZYHhCHZjKe3jNlxED -----END CERTIFICATE----- EOF
- Import the CA root certificate into the keystore (otherwise keytool won't like the CAcert.org root that signs your client certificate). We assume you are on a Debian system with a copy of the CAcert.org roots in /etc/ssl/certs/cacert.org.pem:
$ keytool -import -alias root -keystore ~/.jitsi.keytool -storepass mysecret -trustcacerts -file /etc/ssl/certs/cacert.org.pem ... Trust this certificate? [no]: yes Certificate was added to keystore
- Now import the reply from the CA:
$ keytool -importcert -alias jitsi1 -file /tmp/jitsi1.crt -keystore ~/.jitsi.keytool -storepass jitsi1 Certificate reply was installed in keystore
Setting up the account in the repro web interface
- Go to the repro web interface, be default, it listens on port 5080
- Log in using the password you set in the repro.config file
- Click Domains and add your domain. Leave the port blank.
- Click Add User and add your user name (must match the user portion of the email address in your client certificate)
- At this point, you could check in the database, make sure the user exists in the users table. Check the syslog if it didn't work.
Setting up Jitsi
- Go to the Tools menu, click Options, and find the Advanced tab.
- Click SIP and then remove the check marks next to SSLv2Hello and SSLv3. Only the TLSv1 option should have a check mark.
- You must restart Jitsi after that change
- Click TLS Configuration and the Add button.
- In the Display Name, put some arbitrary name, for example testcert
- Click the Browse button and locate the file ~/.jitsi.keytool that you created. Click OK to dismiss the file chooser dialog.
- Click the Type pulldown and choose the jks options
- In the Password field, put mysecret, or whatever password you used with the keytool command in earlier steps.
- In the field Alias name in KeyStore, choose jitsi1 or whatever alias name you used with keytool in earlier steps.
- Now click OK
- Your certificate details should appear in the table in the Options window
- Now go to the Accounts tab and click the Add button
- In the Network menu, choose SIP.
- Enter the email address as the SIP Id. Leave the Password field blank.
- Click the Advanced button.
- Go to the Connection tab
- In the Client TLS certificate pull down, choose the name that matches the Display Name you chose when you were in the TLS Configuration panel.
- Click Next and accept the settings
- Jitsi will try and connect to your repro SIP proxy
- If it doesn't work, try restarting Jitsi, use the Quit option in the menu - sometimes it doesn't appear to recognise the certificate until after a restart
- You may get a warning to tell you that Jitsi doesn't trust the server's certificate. For testing, just click the Continue Anyway button.
- For production use, it is recommended that you either use a CA trusted by the JRE, or add your CA certificate to the JRE's built in keystore.
- You may get a popup for jks authentication, with a message like The jks server has requested your authentication. In the Password box, insert the password mysecret, or whatever password you used with the keytool command in earlier steps.
- You should now see the green light that says you are Online
If it doesn't work
- In the repro web interface, you can click the REGISTRATIONS menu link to see which users are connected successfully
- Look at any console output from Jitsi
- You can run repro from the command line, for example:
# /etc/init/repro stop # /usr/sbin/repro /etc/repro/repro.config --Daemonize=false --LoggingType=cout --LogLevel=STACK