(Ruby) Convert Java KeyStore to PEM

Loads a Java keystore file and saves the trusted certificate entries to a PEM file.

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

require 'chilkat'

# This requires the Chilkat API to have been previously unlocked.
# See Global Unlock Sample for sample code.

jks = Chilkat::CkJavaKeyStore.new()

jksPassword = "myJksPassword"

# Load the Java keystore from a file.  The JKS file password is used
# to verify the keyed digest that is found at the very end of the keystore.
# It verifies that the keystore has not been modified.
success = jks.LoadFile(jksPassword,"/someDir/keyStore.jks")
if (success != true)
    print jks.lastErrorText() + "\n";
    exit
end

# Open/create the output PEM file. 
# This example uses Chilkat's file access class for writing the output file.
# You may replace the file I/O lines of code with whatever is most convenient for you.
fac = Chilkat::CkFileAccess.new()
success = fac.OpenForWrite("/pemFiles/caCerts.pem")
if (success != true)
    print fac.lastErrorText() + "\n";
    exit
end

numCerts = jks.get_NumTrustedCerts()

# Iterate over the trusted certs, get the PEM for each,
# and append it to the output file.
i = 0
while i < numCerts
    # cert is a CkCert
    cert = jks.GetTrustedCert(i)

    # Get the certificate in PEM format.  
    pem = cert.exportCertPem()

    # Append the PEM string to the open file.
    # The PEM contains only us-ascii chars..
    success = fac.AppendAnsi(pem)
    if (success != true)
        print fac.lastErrorText() + "\n";

        exit
    end

    i = i + 1
end

# Close the output file.
fac.FileClose()

print "Trusted certificates saved to PEM." + "\n";