sslopenssl

SSL Hostname mismatch although CN of client and server match

I generated a ca-certificate, server-certificate and client-certificate using the guidelines of rabbitmq (https://www.rabbitmq.com/ssl.html#manual-certificate-generation)

But I keep getting an error Hostname mismatch when checking the certs with openssl s_server.

openssl s_server -accept 8443 -cert server_certificate.pem -key private_key.pem -CAfile ca_certificate.pem

openssl s_client -connect localhost:8443 -cert client_certificate -key private_key.pem -CAfile ca_certificate.pem -verify 8 -verify_hostname CN_NAME

RESULT:

Verify return code: 62 (Hostname mismatch)

When I read the hostnames, they both show the same..?

openssl x509 -in server_certificate -subject -noout
subject=CN = MyTestCA, O = server

openssl x509 -in client_certificate -subject -noout
subject=CN = MyTestCA, O = client

So I'm stuck why I'm getting the error 'Hostname mismatch'?

Solution

  • Error is due to using the same CN for the CA and server. Solved it by using another CN for the CA.