man SSL_get_SSL_CTX () - get the SSL_CTX from which an SSL is created
NAME
SSL_get_SSL_CTX - get the SSL_CTX from which an SSL is created
SYNOPSIS
#include <openssl/ssl.h>
SSL_CTX *SSL_get_SSL_CTX(const SSL *ssl);
DESCRIPTION
SSL_get_SSL_CTX() returns a pointer to the SSL_CTX object, from which ssl was created with SSL_new(3).
RETURN VALUES
The pointer to the SSL_CTX object is returned.