+=item "mandatory-digest" (B<OSSL_PKEY_PARAM_MANDATORY_DIGEST>) <UTF8 string>
+
+If there is a mandatory digest for performing a signature operation with
+keys from this keymgmt, this parameter should get its name as value.
+
+When EVP_PKEY_get_default_digest_name() queries this parameter and it's
+filled in by the implementation, its return value will be 2.
+
+If the keymgmt implementation fills in the value C<""> or C<"UNDEF">,
+L<EVP_PKEY_get_default_digest_name(3)> will place the string C<"UNDEF"> into
+its argument I<mdname>. This signifies that no digest should be specified
+with the corresponding signature operation.
+
+=item "default-digest" (B<OSSL_PKEY_PARAM_DEFAULT_DIGEST>) <UTF8 string>
+
+If there is a default digest for performing a signature operation with
+keys from this keymgmt, this parameter should get its name as value.
+
+When L<EVP_PKEY_get_default_digest_name(3)> queries this parameter and it's
+filled in by the implementation, its return value will be 1. Note that if
+B<OSSL_PKEY_PARAM_MANDATORY_DIGEST> is responded to as well,
+L<EVP_PKEY_get_default_digest_name(3)> ignores the response to this
+parameter.
+
+If the keymgmt implementation fills in the value C<""> or C<"UNDEF">,
+L<EVP_PKEY_get_default_digest_name(3)> will place the string C<"UNDEF"> into
+its argument I<mdname>. This signifies that no digest has to be specified
+with the corresponding signature operation, but may be specified as an
+option.
+