SSL_CTX_new(3)			    OpenSSL			SSL_CTX_new(3)



NAME
       SSL_CTX_new, SSLv23_method, SSLv23_server_method, SSLv23_client_method,
       TLSv1_2_method, TLSv1_2_server_method, TLSv1_2_client_method,
       TLSv1_1_method, TLSv1_1_server_method, TLSv1_1_client_method,
       TLSv1_method, TLSv1_server_method, TLSv1_client_method, SSLv3_method,
       SSLv3_server_method, SSLv3_client_method, SSLv2_method,
       SSLv2_server_method, SSLv2_client_method, DTLS_method,
       DTLS_server_method, DTLS_client_method, DTLSv1_2_method,
       DTLSv1_2_server_method, DTLSv1_2_client_method, DTLSv1_method,
       DTLSv1_server_method, DTLSv1_client_method - create a new SSL_CTX
       object as framework for TLS/SSL enabled functions

SYNOPSIS
	#include <openssl/ssl.h>

	SSL_CTX *SSL_CTX_new(const SSL_METHOD *method);
	const SSL_METHOD *SSLv23_method(void);
	const SSL_METHOD *SSLv23_server_method(void);
	const SSL_METHOD *SSLv23_client_method(void);
	const SSL_METHOD *TLSv1_2_method(void);
	const SSL_METHOD *TLSv1_2_server_method(void);
	const SSL_METHOD *TLSv1_2_client_method(void);
	const SSL_METHOD *TLSv1_1_method(void);
	const SSL_METHOD *TLSv1_1_server_method(void);
	const SSL_METHOD *TLSv1_1_client_method(void);
	const SSL_METHOD *TLSv1_method(void);
	const SSL_METHOD *TLSv1_server_method(void);
	const SSL_METHOD *TLSv1_client_method(void);
	#ifndef OPENSSL_NO_SSL3_METHOD
	const SSL_METHOD *SSLv3_method(void);
	const SSL_METHOD *SSLv3_server_method(void);
	const SSL_METHOD *SSLv3_client_method(void);
	#endif
	#ifndef OPENSSL_NO_SSL2
	const SSL_METHOD *SSLv2_method(void);
	const SSL_METHOD *SSLv2_server_method(void);
	const SSL_METHOD *SSLv2_client_method(void);
	#endif

	const SSL_METHOD *DTLS_method(void);
	const SSL_METHOD *DTLS_server_method(void);
	const SSL_METHOD *DTLS_client_method(void);
	const SSL_METHOD *DTLSv1_2_method(void);
	const SSL_METHOD *DTLSv1_2_server_method(void);
	const SSL_METHOD *DTLSv1_2_client_method(void);
	const SSL_METHOD *DTLSv1_method(void);
	const SSL_METHOD *DTLSv1_server_method(void);
	const SSL_METHOD *DTLSv1_client_method(void);

DESCRIPTION
       SSL_CTX_new() creates a new SSL_CTX object as framework to establish
       TLS/SSL enabled connections.

NOTES
       The SSL_CTX object uses method as connection method. The methods exist
       in a generic type (for client and server use), a server only type, and
       a client only type. method can be of the following types:

       SSLv23_method(), SSLv23_server_method(), SSLv23_client_method()
	   These are the general-purpose version-flexible SSL/TLS methods.
	   The actual protocol version used will be negotiated to the highest
	   version mutually supported by the client and the server.  The
	   supported protocols are SSLv2, SSLv3, TLSv1, TLSv1.1 and TLSv1.2.
	   Most applications should use these method, and avoid the version
	   specific methods described below.

	   The list of protocols available can be further limited using the
	   SSL_OP_NO_SSLv2, SSL_OP_NO_SSLv3, SSL_OP_NO_TLSv1,
	   SSL_OP_NO_TLSv1_1 and SSL_OP_NO_TLSv1_2 options of the
	   SSL_CTX_set_options(3) or SSL_set_options(3) functions.  Clients
	   should avoid creating "holes" in the set of protocols they support,
	   when disabling a protocol, make sure that you also disable either
	   all previous or all subsequent protocol versions.  In clients, when
	   a protocol version is disabled without disabling all previous
	   protocol versions, the effect is to also disable all subsequent
	   protocol versions.

	   The SSLv2 and SSLv3 protocols are deprecated and should generally
	   not be used.	 Applications should typically use
	   SSL_CTX_set_options(3) in combination with the SSL_OP_NO_SSLv3 flag
	   to disable negotiation of SSLv3 via the above version-flexible
	   SSL/TLS methods.  The SSL_OP_NO_SSLv2 option is set by default, and
	   would need to be cleared via SSL_CTX_clear_options(3) in order to
	   enable negotiation of SSLv2.

       TLSv1_2_method(), TLSv1_2_server_method(), TLSv1_2_client_method()
	   A TLS/SSL connection established with these methods will only
	   understand the TLSv1.2 protocol.  A client will send out TLSv1.2
	   client hello messages and will also indicate that it only
	   understand TLSv1.2.	A server will only understand TLSv1.2 client
	   hello messages.

       TLSv1_1_method(), TLSv1_1_server_method(), TLSv1_1_client_method()
	   A TLS/SSL connection established with these methods will only
	   understand the TLSv1.1 protocol.  A client will send out TLSv1.1
	   client hello messages and will also indicate that it only
	   understand TLSv1.1.	A server will only understand TLSv1.1 client
	   hello messages.

       TLSv1_method(), TLSv1_server_method(), TLSv1_client_method()
	   A TLS/SSL connection established with these methods will only
	   understand the TLSv1 protocol.  A client will send out TLSv1 client
	   hello messages and will indicate that it only understands TLSv1.  A
	   server will only understand TLSv1 client hello messages.

       SSLv3_method(), SSLv3_server_method(), SSLv3_client_method()
	   A TLS/SSL connection established with these methods will only
	   understand the SSLv3 protocol.  A client will send out SSLv3 client
	   hello messages and will indicate that it only understands SSLv3.  A
	   server will only understand SSLv3 client hello messages.  The SSLv3
	   protocol is deprecated and should not be used.

       SSLv2_method(), SSLv2_server_method(), SSLv2_client_method()
	   These calls are provided only as stubs for keeping ABI
	   compatibility. There is no support for SSLv2 built in the library.

       DTLS_method(), DTLS_server_method(), DTLS_client_method()
	   These are the version-flexible DTLS methods.

       DTLSv1_2_method(), DTLSv1_2_server_method(), DTLSv1_2_client_method()
	   These are the version-specific methods for DTLSv1.2.

       DTLSv1_method(), DTLSv1_server_method(), DTLSv1_client_method()
	   These are the version-specific methods for DTLSv1.

       SSL_CTX_new() initializes the list of ciphers, the session cache
       setting, the callbacks, the keys and certificates and the options to
       its default values.

RETURN VALUES
       The following return values can occur:

       NULL
	   The creation of a new SSL_CTX object failed. Check the error stack
	   to find out the reason.

       Pointer to an SSL_CTX object
	   The return value points to an allocated SSL_CTX object.

SEE ALSO
       SSL_CTX_set_options(3), SSL_CTX_clear_options(3), SSL_set_options(3),
       SSL_CTX_free(3), SSL_accept(3), ssl(3),	SSL_set_connect_state(3)



1.0.2k				  2023-11-15			SSL_CTX_new(3)