Using a remote keystore provider

Implement additional providers such as PKCS12.

cassandra.yaml

The location of the cassandra.yaml file depends on the type of installation:
Package installations /etc/dse/cassandra/cassandra.yaml
Tarball installations installation_location/resources/cassandra/conf/cassandra.yaml

DataStax Enterprise (DSE) database uses the Java Cryptography API (JCA) to implement SSL providers. The JCA is a pluggable architecture that abstracts the actual cryptography implementation from the algorithm requested. To support swapping out different implementations, DSE database use Cipher.getInstance("AES").

The JCA architecture Provider class allows multiple implementations to register using a different service provider interface (SPI). Java comes with multiple providers and supports installation of additional providers, such as PKCS12.
Attention: PKCS11 is not supported. Also, due to an OpenSSL issue, you cannot use a PKCS12 truststore that was generated via OpenSSL. For example, a truststore generated via the following command will not work with DSE:
openssl pkcs12 -export -nokeys -out truststore.pfx -in intermediate.chain.pem
However, truststores generated via Java's keytool and then converted to PKCS12 work with DSE. Example:
keytool -importcert -alias rootca -file rootca.pem -keystore truststore.jks
keytool -importcert -alias intermediate -file intermediate.pem -keystore truststore.jks
keytool -importkeystore -srckeystore truststore.jks -destkeystore truststore.pfx -deststoretype pkcs12

PKCS12 is typically used to store private key and certificate information on files. The default keystore type in Java is JKS, though you can specify PKCS12 with the -storetype option when creating a keystore with keytool.

The DSE database keystore type parameter in cassandra.yaml determines which SPI to use.

See related information about PKCS12 as a truststore_type.

Installing additional providers

Install providers using the java.security configuration that comes with the JRE.

Tip: For more detailed instructions, see How to implement a Provider (Oracle).
Add the location to the java.security configuration file, which is located in $JAVA_HOME/lib/security/java.security. For an environment where PKCS12 is the keystore type and a Cassandra-only workload, use: 
security.provider.10=sun.security.pkcs12.SunPKCS12 path-to-pkcs12-provider-config-file
Example: 
security.provider.10=sun.security.pkcs12.SunPKCS12 /opt/bar/cfg/pkcs12.cfg
For details, see the Oracle Java Secure Socket Extension (JSSE) Reference Guide.