EVP_PKEY_cmp(3) OpenSSL EVP_PKEY_cmp(3) NNAAMMEE EVP_PKEY_copy_parameters, EVP_PKEY_missing_parameters, EVP_PKEY_cmp_parameters, EVP_PKEY_cmp - public key parameter and com- parison functions SSYYNNOOPPSSIISS #include int EVP_PKEY_missing_parameters(const EVP_PKEY *pkey); int EVP_PKEY_copy_parameters(EVP_PKEY *to, const EVP_PKEY *from); int EVP_PKEY_cmp_parameters(const EVP_PKEY *a, const EVP_PKEY *b); int EVP_PKEY_cmp(const EVP_PKEY *a, const EVP_PKEY *b); DDEESSCCRRIIPPTTIIOONN The function _E_V_P___P_K_E_Y___m_i_s_s_i_n_g___p_a_r_a_m_e_t_e_r_s_(_) returns 1 if the public key parameters of ppkkeeyy are missing and 0 if they are present or the algo- rithm doesn't use parameters. The function _E_V_P___P_K_E_Y___c_o_p_y___p_a_r_a_m_e_t_e_r_s_(_) copies the parameters from key ffrroomm to key ttoo. An error is returned if the parameters are missing in ffrroomm or present in both ffrroomm and ttoo and mismatch. If the parameters in ffrroomm and ttoo are both present and match this function has no effect. The function _E_V_P___P_K_E_Y___c_m_p___p_a_r_a_m_e_t_e_r_s_(_) compares the parameters of keys aa and bb. The function _E_V_P___P_K_E_Y___c_m_p_(_) compares the public key components and parameters (if present) of keys aa and bb. NNOOTTEESS The main purpose of the functions _E_V_P___P_K_E_Y___m_i_s_s_i_n_g___p_a_r_a_m_e_t_e_r_s_(_) and _E_V_P___P_K_E_Y___c_o_p_y___p_a_r_a_m_e_t_e_r_s_(_) is to handle public keys in certificates where the parameters are sometimes omitted from a public key if they are inherited from the CA that signed it. Since OpenSSL private keys contain public key components too the func- tion _E_V_P___P_K_E_Y___c_m_p_(_) can also be used to determine if a private key matches a public key. RREETTUURRNN VVAALLUUEESS The function _E_V_P___P_K_E_Y___m_i_s_s_i_n_g___p_a_r_a_m_e_t_e_r_s_(_) returns 1 if the public key parameters of ppkkeeyy are missing and 0 if they are present or the algo- rithm doesn't use parameters. These functions _E_V_P___P_K_E_Y___c_o_p_y___p_a_r_a_m_e_t_e_r_s_(_) returns 1 for success and 0 for failure. The function _E_V_P___P_K_E_Y___c_m_p___p_a_r_a_m_e_t_e_r_s_(_) and _E_V_P___P_K_E_Y___c_m_p_(_) return 1 if the keys match, 0 if they don't match, -1 if the key types are differ- ent and -2 if the operation is not supported. SSEEEE AALLSSOO _E_V_P___P_K_E_Y___C_T_X___n_e_w(3), _E_V_P___P_K_E_Y___k_e_y_g_e_n(3) 1.0.2u 2019-12-31 EVP_PKEY_cmp(3)