SSL_CTX_new(3) | OpenSSL | SSL_CTX_new(3) |
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 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.
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. |
July 20, 2009 | 1.0.1-dev |