qtdebuggingopenssl

qt openssl issues, how to further debug?


I am getting weird SSL error message on my deployed application, not on every message but definitely too often. The message in Qt reads:

Error while reading: error:1C80006E:Provider routines::invalid tag

I located the responsible lines as here and here

My question would be: Is there a way to enable advanced debug options in qt and openSSL, so that I can see the messages exchanged and/or SSL internal errors?

Some additional information on what I already tried:

Update: Turned out that inside ossl_gcm_get_ctx_params (code) the AEAD tag length is 0, and therefore it fails. It failed with the same error for four different cases, so it was hard to understand... Found that by using LD_PRELOAD and recompiling openSSL... Do not yet understand what that means but feels like a progress :D


Solution

  • Solved: After way too long days of debugging... another use of OpenSSL within the application was influencing Qt's OpenSSL usage. The mentioned error came from that usage, not Qt's.