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SSL_CTX_new(3)
NAME
  SSL_CTX_new - Create a new SSL_CTX object as framework for TLS/SSL enabled
  functions

SYNOPSIS
  #include <openssl/ssl.h>

  SSL_CTX *SSL_CTX_new(
	  SSL_METHOD *method );

DESCRIPTION
  The SSL_CTX_new() function 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. The method can be of the following types:

  SSLv2_method(void), SSLv2_server_method(void), SSLv2_client_method(void)
	  A TLS/SSL connection established with these methods will only
	  understand the SSLv2 protocol. A client will send out SSLv2 client
	  hello messages and will also indicate that it only understand
	  SSLv2.  A server will only understand SSLv2 client hello messages.

  SSLv3_method(void), SSLv3_server_method(void), SSLv3_client_method(void)
	  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. This
	  especially means, that it will not understand SSLv2 client hello
	  messages which are widely used for compatibility reasons. See
	  SSLv23_*_method().

  TLSv1_method(void), TLSv1_server_method(void), TLSv1_client_method(void)
	  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. This
	  especially means, that it will not understand SSLv2 client hello
	  messages which are widely used for compatibility reasons, see
	  SSLv23_*_method(). It will also not understand SSLv3 client hello
	  messages.

  SSLv23_method(void), SSLv23_server_method(void), SSLv23_client_method(void)
	  A TLS/SSL connection established with these methods will understand
	  the SSLv2, SSLv3, and TLSv1 protocol. A client will send out SSLv2
	  client hello messages and will indicate that it also understands
	  SSLv3 and TLSv1. A server will understand SSLv2, SSLv3, and TLSv1
	  client hello messages.  This is the best choice when compatibility
	  is a concern.

  The list of protocols available can later be limited using the
  SSL_OP_NO_SSLv2, SSL_OP_NO_SSLv3, SSL_OP_NO_TLSv1 options of the
  SSL_CTX_set_options() or SSL_set_options() functions.	 Using these options,
  it is possible to choose the SSLv23_server_method() function, for example,
  and be able to negotiate with all possible clients, but to only allow newer
  protocols like SSLv3 or TLSv1.

  The SSL_CTX_new() function 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 determine the reason.

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

SEE ALSO
  Functions: SSL_CTX_free(3), SSL_accept(3), ssl(3), SSL_set_connect_state(3)

Index for Section 3

Alphabetical listing for S

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