SSL_CTX_set_cipher_list(3)  OpenSSL  SSL_CTX_set_cipher_list(3)





NAME
       SSL_CTX_set_cipher_list, SSL_set_cipher_list - choose
       list of available SSL_CIPHERs

SYNOPSIS
        #include <openssl/ssl.h>

        int SSL_CTX_set_cipher_list(SSL_CTX *ctx, const char *str);
        int SSL_set_cipher_list(SSL *ssl, const char *str);

DESCRIPTION
       SSL_CTX_set_cipher_list() sets the list of available
       ciphers for ctx using the control string str. The format
       of the string is described in ciphers(1). The list of
       ciphers is inherited by all ssl objects created from
       ctx.

       SSL_set_cipher_list() sets the list of ciphers only for
       ssl.

NOTES
       The control string str should be universally usable and
       not depend on details of the library configuration
       (ciphers compiled in). Thus no syntax checking takes
       place. Items that are not recognized, because the corre-
       sponding ciphers are not compiled in or because they are
       mistyped, are simply ignored. Failure is only flagged if
       no ciphers could be collected at all.

       It should be noted, that inclusion of a cipher to be
       used into the list is a necessary condition. On the
       client side, the inclusion into the list is also suffi-
       cient. On the server side, additional restrictions
       apply. All ciphers have additional requirements. ADH
       ciphers don't need a certificate, but DH-parameters must
       have been set. All other ciphers need a corresponding
       certificate and key.

       A RSA cipher can only be chosen, when a RSA certificate
       is available.  RSA export ciphers with a keylength of
       512 bits for the RSA key require a temporary 512 bit RSA
       key, as typically the supplied key has a length of 1024
       bit (see SSL_CTX_set_tmp_rsa_callback(3)).  RSA ciphers
       using EDH need a certificate and key and additional DH-
       parameters (see SSL_CTX_set_tmp_dh_callback(3)).

       A DSA cipher can only be chosen, when a DSA certificate
       is available.  DSA ciphers always use DH key exchange
       and therefore need DH-parameters (see
       SSL_CTX_set_tmp_dh_callback(3)).

       When these conditions are not met for any cipher in the
       list (e.g. a client only supports export RSA ciphers
       with a asymmetric key length of 512 bits and the server
       is not configured to use temporary RSA keys), the "no
       shared cipher" (SSL_R_NO_SHARED_CIPHER) error is gener-
       ated and the handshake will fail.

RETURN VALUES
       SSL_CTX_set_cipher_list() and SSL_set_cipher_list()
       return 1 if any cipher could be selected and 0 on com-
       plete failure.

SEE ALSO
       ssl(3), SSL_get_ciphers(3), SSL_CTX_use_certificate(3),
       SSL_CTX_set_tmp_rsa_callback(3),
       SSL_CTX_set_tmp_dh_callback(3), ciphers(1)



0.9.7c                     2001-07-23SSL_CTX_set_cipher_list(3)
