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