Hi,
We are running an OpenSSL based web server and using Chrome/Firefox as the web client.
We need to implement server initiated renegotiation for client certificate verification.
We were earlier using OpenSSL 1.0.2 and TLS 1.2 and were able to do the renegotiation using the below code sequence:
- SSL_renegotiate
- SSL_do_handshake
- SSL_set_state(ssl, SSL_ST_ACCEPT)
- SSL_do_handshake
- SSL_get_peer_certificate
Using the above code sequence, we are successfully able to complete the handshake after the renegotiation and verify the client certificate.
We are currently migrating to OpenSSL 3.0.8.
In the migration guide or the OpenSSL documentation, we couldn't find any replacement for the SSL_set_state API.
However, we updated our code as below and got the renegotiation working for TLS 1.2 for Chrome and Microsoft Edge:
- SSL_renegotiate
- SSL_do_handshake
- SSL_read
- SSL_get_peer_certificate
However, with the same code sequence, the handshake fails in the case of Mozilla Firefox.
On debugging using SSL_trace, we found that in case of Firefox, the client (browser) sends an Alert Message 21 after sending a ClientKeyExchange message.
We have below queries:
- What is the correct code sequence to implement server initiated renegotiation for client certificate verification using OpenSSL 3.0.8 using TLS1.2 ?
- What is the replacement for the SSL_set_state(ssl, SSL_ST_ACCEPT) API in OpenSSL 3.0.8 or how can we set the state to SSL_ST_ACCEPT?
- How to do server initiated renegotiation for client certificate verification using OpenSSL 3.0.8.
