(Ruby) Find Certificate on Smartcard Currenty in Reader

Finds the certificates on smartcards currently in readers.

Note: This example requires Chilkat v9.5.0.77 or greater.

Chilkat Ruby Downloads install from rubygems.org gem install chilkat or download... Ruby Library for Windows, MacOS, Linux, Alpine Linux

require 'chilkat'

# This newer example is a much better way to get the certificate on a smartcard or USB token

# This example requires that we already know the name of the CSP (Cryptographic Service Provider) for the smartcard.
# It is often the "Microsoft Base Smart Card Crypto Provider".  You can see what CSP's are registered on your system with this code:

csp = Chilkat::CkCsp.new()
st = Chilkat::CkStringTable.new()

success = csp.GetProviders(st)
if (success == false)
    print csp.lastErrorText() + "\n";
    exit
end

# Iterate over the CSP names..
i = 0
numProviders = st.get_Count()
while i < numProviders
    print i.to_s() + ": " + st.stringAt(i) + "\n";
    i = i + 1
end

# --------------------------
# This newer example is a much better way to get the certificate on a smartcard or USB token

# We'll assume our smartcard is accessed through the "Microsoft Base Smart Card Crypto Provider"
# Also, we'll assume that the certificate has been installed into the default current user Windows
# certificate store by following the instructions provided by the smartcard vendor.
# (The certificate does not contain the private key.  The certificate should be installed in the
# Windows current user certificate store.  It will also be on the smartcard, and the associated private
# key is only on the smartcard.)
# 

# First open the Current User Certificate Store.  We'll need it soon..
certStore = Chilkat::CkCertStore.new()
success = certStore.OpenCurrentUserStore(true)
if (success == false)
    print certStore.lastErrorText() + "\n";
    exit
end

# Create a Csp object and set the ProviderName equal to our desired CSP name.
# (setting the ProviderName selects the desired CSP.)
csp.put_ProviderName("Microsoft Base Smart Card Crypto Provider")

# Iterate over the key containers managed by this CSP.
# These will be the key containers for the cards currently inserted into the reader(s).
# If only one smartcard reader exists, and a smartcard is inserted, there should be one
# key container.
numContainers = csp.get_NumKeyContainers()

print "numContainers = " + numContainers.to_s() + "\n";

i = 0
while i < numContainers
    # For each key container, get the key container name and then find the certificate
    # in the Current User Certicate Store with the matching key container name.
    keyContainerName = csp.nthKeyContainerName(i)

    # cert is a CkCert
    cert = certStore.FindCertByKeyContainer(keyContainerName)
    if (certStore.get_LastMethodSuccess() == true)
        print "Certificate in reader: " + cert.subjectCN() + "\n";

    end

    i = i + 1
end