OCSP response signed by self-signed trusted responder validation
Have a question with implementing an OCSP requestor that can handle validating an OCSP response that is not signed by the CA who issued the certificate that we are requesting the OCSP status for but rather,
the OCSP response is signed by a self-signed trusted responder that includes the OCSP Signing EKU and the self-signed certificate is configured as trusted on the requesting system.
Question is how to get past the check in OCSP_basic_verify() that calls ocsp_check_issuer() with the responder chain and fails in ocsp_match_issuerid() since the issuer ID doesn’t match the self-signed responder
certificate ID causing the verify to fail with ‘OCSP routines:OCSP_basic_verify:root ca not trusted in ocsp_vfy.c line 176.’
Could someone please shed light on how this is expected to work for this scenario? Is it expected that the self-signed certificate needs to be added to have explicit trust so that it is allowed via the call
to X509_check_trust() or is there something else I’m missing here?
directly by the CA, indicating that the responder may issue OCSP
responses for that CA
I’m seeing the self-signed and/or even a separate PKI root or hierarchy that is designated to sign responses as the 2nd option above which is essentially an ‘out of band’ trust that is configured
on the requestor ahead of time. Are you saying option 2 from the RFC is not supported within OpenSSL and would require changes? Or am I misinterpreting option 2 above.
Lastly, I assuming my understanding is correct, I was thinking X509_check_trust() allows for communicating this ‘out of band’ trust to OpenSSL for validation of OCSP responses, is this not what this trust
setting is for?