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
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