Set Up Smart Card Redirection on an Ubuntu Virtual Machine

To configure smart card redirection on an Ubuntu virtual machine (VM), install the libraries on which the feature depends and the root CA certificate to support the trusted authentication of smart cards. In addition, you must edit some configuration files to complete the authentication setup.

Some examples in the procedure use placeholder values to represent entities in your network configuration, such as the DNS name of your AD domain. Replace the placeholder values with information specific to your configuration, as described in the following table.


Placeholder Value	Description
dns_IP_ADDRESS	IP address of your DNS name server
mydomain.com	DNS name of your AD domain
MYDOMAIN.COM	DNS name of your AD domain, in all capital letters
MYDOMAIN	DNS name of the workgroup or NT domain that includes your Samba server, in all capital letters
ads-hostname	Host name of your AD server
ads-hostname.mydomain.com	Fully qualified domain name (FQDN) of your AD server
mytimeserver.mycompany.com	DNS name of your NTP time server
AdminUser	User name of the VM administrator

Prerequisites

Integrate an Ubuntu Virtual Machine with Active Directory for Smart Card Redirection

Procedure

Install the required libraries on the Ubuntu VM.

apt-get install -y pcscd pcsc-tools pkg-config libpam-pkcs11 opensc
      libengine-pkcs11-openssl libnss3-tools

Install a Root Certification Authority (CA) certificate.
1. Download a root CA certificate and save it to /tmp/certificate.cer on the Ubuntu VM. See How to Export Root Certification Authority Certificate.
2. Locate the root CA certificate that you downloaded, and transfer it to a .pem file.
```
openssl x509 -inform der -in /tmp/certificate.cer -out /tmp/certificate.pem
```
3. Use the certutil command to install the root CA certificate to the system database /etc/pki/nssdb.
```
certutil -A -d /etc/pki/nssdb -n "root CA cert" -t "CT,C,C" -i /tmp/certificate.pem
```
4. Copy the root CA certificate to the /etc/pam_pkcs11/cacerts directory.
```
mkdir -p /etc/pam_pkcs11/cacerts

cp /tmp/certificate.pem /etc/pam_pkcs11/cacerts
```

Create a pkcs11 hash file.

chmod a+r certificate.pem
pkcs11_make_hash_link

Copy the required drivers and add the necessary library files to the nssdb directory.

Run the following commands.

cp libcmP11.so /usr/lib/
mkdir -p /etc/pki/nssdb
certutil -N -d /etc/pki/nssdb
certutil -A -n rootca -i certificate.pem -t "CT,CT,CT" -d /etc/pki/nssdb
modutil -dbdir /etc/pki/nssdb/  -add "piv card 2.0" -libfile /usr/lib/libcmP11.so

Verify that the expected certificate is loaded successfully.
```
certutil -L -d /etc/pki/nssdb

Certificate Nickname

rootca
```

Verify that the expected libraries are added successfully.

modutil -dbdir /etc/pki/nssdb -list

Listing of PKCS #11 Modules
–-----------------------------------------------------------
  1. NSS Internal PKCS #11 Module
         slots: 2 slots attached
        status: loaded

         slot: NSS Internal Cryptographic Services
        token: NSS Generic Crypto Services

         slot: NSS User Private Key and Certificate Services
        token: NSS Certificate DB

  2. piv card 2.0
        library name: /usr/lib/libcmP11.so
         slots: There are no slots attached to this module
        status: loaded
–-----------------------------------------------------------

Configure the pam_pkcs11 library.

Create a pam_pkcs11.conf file using default example content.

For Ubuntu 16.04, 18.04, or 20.04, run the following command sequence.

mkdir /etc/pam_pkcs11
zcat /usr/share/doc/libpam-pkcs11/examples/pam_pkcs11.conf.example.gz | tee /etc/pam_pkcs11/pam_pkcs11.conf

For Ubuntu 20.04.1 or later, run the following command sequence.

mkdir /etc/pam_pkcs11
cat /usr/share/doc/libpam-pkcs11/examples/pam_pkcs11.conf.example | tee /etc/pam_pkcs11/pam_pkcs11.conf

Edit the /etc/pam_pkcs11/pam_pkcs11.conf file as shown in the following example.

use_pkcs11_module = mysc;                            
        
pkcs11_module mysc {                                 
              module = /usr/lib/libcmP11.so;         
              description = "LIBCMP11";               
              slot_num = 0;                           
              ca_dir = /etc/pam_pkcs11/cacerts;       
              nss_dir = /etc/pki/nssdb;        
              cert_policy = ca;                       
}                                                    
...
use_mappers = cn, null;                        
...
mapper cn {
      debug = false;
      module = internal;
      # module = /lib/pam_pkcs11/cn_mapper.so;
      ignorecase = true;
      mapfile = file:///etc/pam_pkcs11/cn_map;         
      # mapfile = "none";
}

Edit the /etc/pam_pkcs11/cn_map file so that it includes the following line.
```
ads-hostname -> ads-hostname
```

Configure the PAM authentication.

Edit the /etc/pam.d/gdm-password configuration file. Place the pam_pkcs11.so authorization line before the common-auth line, as shown in the following example.

#%PAM-1.0
auth    requisite       pam_nologin.so
auth    required        pam_succeed_if.so user != root quiet_success
auth sufficient pam_pkcs11.so                                                                               
@include common-auth
auth    optional        pam_gnome_keyring.so
@include common-account

For Ubuntu 16.04, edit the /etc/pam.d/lightdm configuration file. Place the pam_pkcs11.so authorization line before the common-auth line, as shown in the following example.

#%PAM-1.0
auth    requisite       pam_nologin.so debug
auth    sufficient      pam_succeed_if.so user ingroup nopasswdlogin debug
auth    [success=3 default=ignore}     pam_pkcs11.so                                   
@include common-auth
auth    optional        pam_gnome_keyring.so
auth    optional        pam_kwallet.so

For Ubuntu 16.04, edit the /etc/pam.d/unity configuration file. Place the pam_pkcs11.so authorization line before the common-auth line, as shown in the following example.
```
auth    [success=3 default=ignore}     pam_pkcs11.so                                   
@include common-auth
auth optional pam_gnome_keyring.so
```

To verify the smart card hardware and the certificates installed on the smart card, run the following commands.
```
pcsc_scan

pkcs11_listcerts

pkcs11_inspect
```
Configure the pcscd service to start automatically after the VM restarts.

Note: If the pcscd service does not start after the VM restarts, the first login through pam_pkcs11 fails.
1. Edit the /lib/systemd/system/pcscd.service file by adding the line WantedBy=multi-user.target to the [Install] section.
  Verify that the edited file resembles the following example.
```
[Unit]
Description=PC/SC Smart Card Daemon
Requires=pcscd.socket

[Service]
ExecStart=/usr/sbin/pcscd --foreground --auto-exit
ExecReload=/usr/sbin/pcscd --hotplug

[Install]
WantedBy=multi-user.target
Also=pcscd.socket
```
2. Enable the pcscd service.
```
systemctl enable pcscd.service
```

Update the PC/SC Lite library to version 1.8.8, using the following sequence of commands.

apt-get install -y git autoconf automake libtool flex libudev-dev
git clone https://salsa.debian.org/rousseau/PCSC.git
cd PCSC/
git checkout -b pcsc-1.8.8 1.8.8
./bootstrap
./configure --prefix=/usr --sysconfdir=/etc --libdir=/lib/x86_64-linux-gnu/ 
   CFLAGS="-g -O2 -fstack-protector-strong -Wformat -Werror=format-security" 
   LIBS="-ldl" LDFLAGS="-Wl,-Bsymbolic-functions -Wl,-z,relro" 
   CPPFLAGS="-Wdate-time -D_FORTIFY_SOURCE=2"
make
make install

Install the Horizon Agent package, with smart card redirection enabled.
```
sudo ./install_viewagent.sh -m yes
```
Restart the Ubuntu VM and log back in.