SSL_CTX_new(3) OpenSSL SSL_CTX_new(3) NNAAMMEE 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 SSYYNNOOPPSSIISS #include 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); DDEESSCCRRIIPPTTIIOONN _S_S_L___C_T_X___n_e_w_(_) creates a new SSSSLL__CCTTXX object as framework to establish TLS/SSL enabled connections. NNOOTTEESS The SSL_CTX object uses mmeetthhoodd as connection method. The methods exist in a generic type (for client and server use), a server only type, and a client only type. mmeetthhoodd can be of the following types: _S_S_L_v_2_3___m_e_t_h_o_d_(_), _S_S_L_v_2_3___s_e_r_v_e_r___m_e_t_h_o_d_(_), _S_S_L_v_2_3___c_l_i_e_n_t___m_e_t_h_o_d_(_) These are the general-purpose _v_e_r_s_i_o_n_-_f_l_e_x_i_b_l_e SSL/TLS methods. The actual protocol version used will be negotiated to the highest version mutually supported by the client and the server. The sup- ported 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 SSSSLL__OOPP__NNOO__SSSSLLvv22, SSSSLL__OOPP__NNOO__SSSSLLvv33, SSSSLL__OOPP__NNOO__TTLLSSvv11, SSSSLL__OOPP__NNOO__TTLLSSvv11__11 and SSSSLL__OOPP__NNOO__TTLLSSvv11__22 options of the _S_S_L___C_T_X___s_e_t___o_p_t_i_o_n_s(3) or _S_S_L___s_e_t___o_p_t_i_o_n_s(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 _a_l_l previous pro- tocol versions, the effect is to also disable all subsequent proto- col versions. The SSLv2 and SSLv3 protocols are deprecated and should generally not be used. Applications should typically use _S_S_L___C_T_X___s_e_t___o_p_t_i_o_n_s(3) in combination with the SSSSLL__OOPP__NNOO__SSSSLLvv33 flag to disable negotiation of SSLv3 via the above _v_e_r_s_i_o_n_-_f_l_e_x_i_b_l_e SSL/TLS methods. The SSSSLL__OOPP__NNOO__SSSSLLvv22 option is set by default, and would need to be cleared via _S_S_L___C_T_X___c_l_e_a_r___o_p_t_i_o_n_s(3) in order to enable negotiation of SSLv2. _T_L_S_v_1___2___m_e_t_h_o_d_(_), _T_L_S_v_1___2___s_e_r_v_e_r___m_e_t_h_o_d_(_), _T_L_S_v_1___2___c_l_i_e_n_t___m_e_t_h_o_d_(_) 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 under- stand TLSv1.2. A server will only understand TLSv1.2 client hello messages. _T_L_S_v_1___1___m_e_t_h_o_d_(_), _T_L_S_v_1___1___s_e_r_v_e_r___m_e_t_h_o_d_(_), _T_L_S_v_1___1___c_l_i_e_n_t___m_e_t_h_o_d_(_) 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 under- stand TLSv1.1. A server will only understand TLSv1.1 client hello messages. _T_L_S_v_1___m_e_t_h_o_d_(_), _T_L_S_v_1___s_e_r_v_e_r___m_e_t_h_o_d_(_), _T_L_S_v_1___c_l_i_e_n_t___m_e_t_h_o_d_(_) 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. _S_S_L_v_3___m_e_t_h_o_d_(_), _S_S_L_v_3___s_e_r_v_e_r___m_e_t_h_o_d_(_), _S_S_L_v_3___c_l_i_e_n_t___m_e_t_h_o_d_(_) 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. _S_S_L_v_2___m_e_t_h_o_d_(_), _S_S_L_v_2___s_e_r_v_e_r___m_e_t_h_o_d_(_), _S_S_L_v_2___c_l_i_e_n_t___m_e_t_h_o_d_(_) 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. The SSLv2 protocol offers little to no security and should not be used. As of OpenSSL 1.0.2g, EXPORT ciphers and 56-bit DES are no longer available with SSLv2. _D_T_L_S___m_e_t_h_o_d_(_), _D_T_L_S___s_e_r_v_e_r___m_e_t_h_o_d_(_), _D_T_L_S___c_l_i_e_n_t___m_e_t_h_o_d_(_) These are the version-flexible DTLS methods. _D_T_L_S_v_1___2___m_e_t_h_o_d_(_), _D_T_L_S_v_1___2___s_e_r_v_e_r___m_e_t_h_o_d_(_), _D_T_L_S_v_1___2___c_l_i_e_n_t___m_e_t_h_o_d_(_) These are the version-specific methods for DTLSv1.2. _D_T_L_S_v_1___m_e_t_h_o_d_(_), _D_T_L_S_v_1___s_e_r_v_e_r___m_e_t_h_o_d_(_), _D_T_L_S_v_1___c_l_i_e_n_t___m_e_t_h_o_d_(_) These are the version-specific methods for DTLSv1. _S_S_L___C_T_X___n_e_w_(_) initializes the list of ciphers, the session cache set- ting, the callbacks, the keys and certificates and the options to its default values. RREETTUURRNN VVAALLUUEESS 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. SSEEEE AALLSSOO _S_S_L___C_T_X___s_e_t___o_p_t_i_o_n_s(3), _S_S_L___C_T_X___c_l_e_a_r___o_p_t_i_o_n_s(3), _S_S_L___s_e_t___o_p_t_i_o_n_s(3), _S_S_L___C_T_X___f_r_e_e(3), _S_S_L___a_c_c_e_p_t(3), _s_s_l(3), _S_S_L___s_e_t___c_o_n_n_e_c_t___s_t_a_t_e(3) 1.0.2u 2019-12-20 SSL_CTX_new(3)