There are many services on the Internet providing "echo" API, for example I found the following:
However none of them seem to consider client TLS certificates. I found https://tcpbin.com/, but unfortunately I doesn't have HTTP server behind and no "echo" service as such, moreover it only allows client certificates generated my the service itself, which is not crazy good for my use case.
Is anyone aware of an "echo" API, which supports output of client TLS certificate details?
Found this question here which points to this API:
https://certauth.cryptomix.com/json/
Trying to access it without certificates will respond with 403 Forbidden:
curl --location 'https://certauth.cryptomix.com/json/'
Adding the certificates will respond with 200 and replay the certificate data:
curl --key your_key.pem --cert your_cert.pem -k https://certauth.cryptomix.com/json/