Hi,
I am working on a client where I need to login to a FTPS server (vsftpd). I establish the connection, exchange Hellos, certificate & key exchange and all seems succesful and are happening fine.
I am able to send "PBSZ 0" to the server which gets acknowledged with "200 PBSZ set to 0." (as seen in Wireshark).
Then, when it comes to sending "PROT P", I cannot see it encoded in Wireshark. it just says "Application Data" and the next frame reads "Alert (Level: Fatal, Description: Bad Record Mac)". I have investigated my code (mostly for differences between "PBSZ 0" and "PROT P" but came up empty) and have searched the web but have failed to find the resolution to my problem, as of yet. It seems obvious that the problem must be in my code but I seem to be unable to put my finger on it! I thought I should check if someone here may have any other hints that will help me resolve the problem.
I have temporarily set "mbedtls_ssl_conf_authmode( &ctxt.conf, MBEDTLS_SSL_VERIFY_NONE);" to make sure that the CA is not the causing any issues.
Thank you!