Post quantum keys(Dilithium3) signed certificate generation for Server and Client Authentication

[suyogamnil]

Hello, I am new to EJBCA and was trying to generate a leaf certificate signed using DILITHIU3 key algorithm.
Steps Completed:

1. Created a CA and SUB CA signed by Dilithium3 (prerequisites: Crypto token, Certificate Profile created)
2. Created Certificate profile clone from SERVER profile with extended Key Usage using Server and Client Authentication. Uses SUBCA for signing.
3. Then I created End Entity profile pointing to the certificate Profile created in Step 2.
4. Then I tried creating the certificate using RA web but only certificate was generated but has no private key. The next method i tried was generating CSR using ejbca Command that generates CSR along with private key i.e.
   ejbca.sh gencsr --keyalg DILITHIUM3 --sigalg DILITHIUM3 --subjectdn "CN=bim.com"
   which produces following error

2025-02-05 05:01:10,596+0000 ERROR [org.ejbca.ui.cli.csr.CreateCsrCommand] (main) Could not create signer for DILITHIUM3. Error message: cannot create signer: unknown private key passed to ML-DSA
2025-02-05 05:01:10,596+0000 ERROR [org.ejbca.ui.cli.csr.CreateCsrCommand] (main) debug
org.bouncycastle.operator.OperatorCreationException: cannot create signer: unknown private key passed to ML-DSA
	at org.bouncycastle.operator.jcajce.JcaContentSignerBuilder.build(Unknown Source) ~[bcpkix-jdk18on-1.78.jar:?]
	at org.ejbca.ui.cli.csr.CreateCsrCommand.execute(CreateCsrCommand.java:310) [ejbca-ejb-cli.jar:EJBCA 9.0.0 Community (7fb810e779ded2d8152e89a6d47e83d5fdcf8e4a)]
	at org.ejbca.ui.cli.infrastructure.command.CommandBase.execute(CommandBase.java:108) [keyfactor-commons-cli-2.0.0.jar:?]
	at org.ejbca.ui.cli.infrastructure.library.CommandLibrary$Branch.execute(CommandLibrary.java:309) [keyfactor-commons-cli-2.0.0.jar:?]
	at org.ejbca.ui.cli.infrastructure.library.CommandLibrary.findAndExecuteCommandFromParameters(CommandLibrary.java:88) [keyfactor-commons-cli-2.0.0.jar:?]
	at org.ejbca.ui.cli.EjbcaEjbCli.main(EjbcaEjbCli.java:38) [ejbca-ejb-cli.jar:EJBCA 9.0.0 Community (7fb810e779ded2d8152e89a6d47e83d5fdcf8e4a)]
Caused by: java.security.InvalidKeyException: unknown private key passed to ML-DSA
	at org.bouncycastle.jcajce.provider.asymmetric.mldsa.SignatureSpi.signInit(Unknown Source) ~[bcprov-jdk18on-1.78.jar:?]
	at org.bouncycastle.jcajce.provider.asymmetric.util.BaseDeterministicOrRandomSignature.engineInitSign(Unknown Source) ~[bcprov-jdk18on-1.78.jar:?]
	at java.security.Signature.initSign(Unknown Source) ~[?:?]

Can anyone help me with this?

[primetomas]

I would not care about Dilithium at all in fact. EJBCA 9.1 will soon be out where you will find full ML-DSA / FIPS 204 support. That's where you want to go.
Didn't know about this issue though, looks like a CLI specific issue. If you really want to use dilithium (not worth it in my opinion) you could use 8.3 which was fully tested with Dilithium. EJBCA Community 9.0 is interim until 9.1 is out with proper FIPS 204 support.

[primetomas]

8.3 for Dilithium, wait for 9.1 for ML-DSA. We've removed Dilithium completely going forward.

[suyogamnil]

Sure will be waiting for 9.1. Thank You.

[suyogamnil]

Hello, I successfully installed ejbca 8.3.1 version and created private key and csr with the command I mentioned above and generated the Certificate after signing the CSR. Then I tried verifying it with Openquantum safe nginx by using the certificate and private key. The command used was:
docker run -v --detach --rm --name qest.com --network nginx-test -v /pqc/oqs-demos/nginx/nginx/nginx.conf:/opt/nginx/nginx-conf/nginx.conf -v `pwd`:/opt/nginx/pki1 -p 4433:4433 openquantumsafe/nginx
.
But got following error:

nginx: [emerg] SSL_CTX_use_certificate("/opt/nginx/pki1/bim.com.pem") failed (SSL: error:03000072:digital envelope routines::decode error error:0A00018F:SSL routines::ee key too small)

when I tried verifying the private key using openquantum safe openssl using
openssl pkey -in privkey.pem -pubout -out pubkey.pem

got following error:

286B21DA647C0000:error:1608010C:STORE routines:ossl_store_handle_load_result:unsupported:crypto/store/store_result.c:151:

Could this be that the private encoding is not accepted by the oqs(openquantum safe) openssl or could this mean there was some issue in private key generation.

I think it will be good for me to just ditch out Dilithium and just wait out for ML-DSA.

[primetomas]

Yes, you will not get any relevant interoperability with Dilithium. There were different versions flouting around, mixing between Round 2, Round 3 and FIPS draft. And it's irrelevant anyhow since ML-DSA is different. My advice is really wait out for ML-DSA.

OpenSSL will release with ML-DSA soon as well, then you will be able to run some real use cases with Bouncy Castle, OpenSSL, EJBCA, SignServer and more.