Hi malikfehan123,
So sorry for non-response, I was traveling overseas last week but I am back in the office now!
I scanned the domain in question and it only supports static cipher suites as you found and tried to define BUILD_TLS_DHE_RSA_WITH_AES_128_CBC_SHA it looks like you were on the right track. However instead of defining that you should instead use:
#define WOLFSSL_STATIC_RSA
to enable static cipher suites.
A -188 is an ASN NO SIGNER TO CONFIRM FAILURE error. This is typically a result of attempting to do peer authentication with a certificate that was not found in the cert chain sent by the peer. Please make sure to load the correct certificate with
wolfSSL_CTX_load_verify_buffer
when doing peer authentication. I browsed to the site in question and inspected the page for security details. It looks like the root CA for that domain is: "Avast trusted CA". Please place the "Avast trusted CA" in a cert buffer and load with wolfSSL_CTX_load_verify_buffer when connecting to that site.
Interesting note on: inetupload.indsci.com
If you connect to http://inetupload.indsci.com:443 (Notice HTTP and not HTTPS) you can get a download so you can completely bypass SSL/TLS altogether. If that is your domain I recommend fixing that before going live! If you correctly browse to: https://inetupload.indsci.com:443 then no download and you can view the certificate information
Setting FP_MAX_BITS >=8192 means you have an RSA certificate in your cert chain that is using a 4096-bit RSA key. The examples from TI are fine-tuned for heap/stack use. You may need to bump the size of your stack to allow for this additional RSA-key size as the defaults only use 2048 bit keys if I remember correctly.
Warm Regards,
Kaleb