when securely connect(SSL), reconnection callback error(-114)

[c.w-park]

Hi, everyone!

I am using the official version of espressif' 「ESP8266 NONOS SDK 2.2.0」.
(https://github.com/espressif/ESP8266_NONOS_SDK/releases)

However, it is a difficult situation due to errors in Secure (SSL) communication.
I would like a lot of help and advice.

【Background】
Referring to the source code of the existing IoT_Demo,
You can see that it uses "libssl.a" in the SSL communication.
However, this library does not seem to support the SHA-2 algorithm.
So I try to use mbedlib' "libmbedlib.a" link.

【Question】
■How to use "libmbedlib.a"
1)I already have "libmbedlib.a" in the SDK's lib (ESP8266_NONOS_SDK-2.2.0 \ lib) folder.
Can I just change "-lssl" → "-lmbedtls" in the user application's makefile?

2)Especially, there was a difference between the header file(espconn.h) of "ESP8266_NONOS_SDK-2.2.0\third_party\include\lwip\app" and the header file(espconn.h) of "ESP8266_NONOS_SDK - 2.2.0 \ include", is there a problem?

■About errors and how to fix them
3) In the makefile, change "-lssl" → "-lmbedtls",
When executing 「espconn_secure_connect」, a "-114" error occurs from the CallBack function registered in espconn_regist_reconcb' function.
What does this error(-114) mean?
And how can you solve it?

pls, help me!

[Her Majesty]

Can this doc help? https://www.espressif.com/en/support/do ... s?keys=SSL