SSL_CTX_NEW(3) OpenSSL SSL_CTX_NEW(3)NAMESSL_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);
DESCRIPTIONSSL_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:
SSLv2_client_method(void)SSLv2_method(void), SSLv2_server_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 under-
stand SSLv2 client hello messages.
SSLv3_client_method(void)SSLv3_method(void), SSLv3_server_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_client_method(void)TLSv1_method(void), TLSv1_server_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_client_method(void)SSLv23_method(void), SSLv23_server_method(void),
MirOS BSD #10-current 2005-02-05 1
SSL_CTX_NEW(3) OpenSSL SSL_CTX_NEW(3)
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 compatibil-
ity 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 e.g.
SSLv23_server_method() and be able to negotiate with all
possible clients, but to only allow newer protocols like
SSLv3 or TLSv1.
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 ALSOSSL_CTX_free(3), SSL_accept(3), ssl(3),
SSL_set_connect_state(3)MirOS BSD #10-current 2005-02-05 2