diff options
Diffstat (limited to 'crypto/openssl/doc/ssl/SSL_CTX_set_tmp_rsa_callback.pod')
-rw-r--r-- | crypto/openssl/doc/ssl/SSL_CTX_set_tmp_rsa_callback.pod | 23 |
1 files changed, 8 insertions, 15 deletions
diff --git a/crypto/openssl/doc/ssl/SSL_CTX_set_tmp_rsa_callback.pod b/crypto/openssl/doc/ssl/SSL_CTX_set_tmp_rsa_callback.pod index 534643c..8794eb7 100644 --- a/crypto/openssl/doc/ssl/SSL_CTX_set_tmp_rsa_callback.pod +++ b/crypto/openssl/doc/ssl/SSL_CTX_set_tmp_rsa_callback.pod @@ -74,21 +74,14 @@ exchange and use EDH (Ephemeral Diffie-Hellman) key exchange instead in order to achieve forward secrecy (see L<SSL_CTX_set_tmp_dh_callback(3)|SSL_CTX_set_tmp_dh_callback(3)>). -On OpenSSL servers ephemeral RSA key exchange is therefore disabled by default -and must be explicitly enabled using the SSL_OP_EPHEMERAL_RSA option of -L<SSL_CTX_set_options(3)|SSL_CTX_set_options(3)>, violating the TLS/SSL -standard. When ephemeral RSA key exchange is required for export ciphers, -it will automatically be used without this option! - -An application may either directly specify the key or can supply the key via -a callback function. The callback approach has the advantage, that the -callback may generate the key only in case it is actually needed. As the -generation of a RSA key is however costly, it will lead to a significant -delay in the handshake procedure. Another advantage of the callback function -is that it can supply keys of different size (e.g. for SSL_OP_EPHEMERAL_RSA -usage) while the explicit setting of the key is only useful for key size of -512 bits to satisfy the export restricted ciphers and does give away key length -if a longer key would be allowed. +An application may either directly specify the key or can supply the key via a +callback function. The callback approach has the advantage, that the callback +may generate the key only in case it is actually needed. As the generation of a +RSA key is however costly, it will lead to a significant delay in the handshake +procedure. Another advantage of the callback function is that it can supply +keys of different size while the explicit setting of the key is only useful for +key size of 512 bits to satisfy the export restricted ciphers and does give +away key length if a longer key would be allowed. The B<tmp_rsa_callback> is called with the B<keylength> needed and the B<is_export> information. The B<is_export> flag is set, when the |