diff options
Diffstat (limited to 'crypto/openssl/doc/ssl/SSL_CTX_set_tmp_dh_callback.pod')
-rw-r--r-- | crypto/openssl/doc/ssl/SSL_CTX_set_tmp_dh_callback.pod | 21 |
1 files changed, 10 insertions, 11 deletions
diff --git a/crypto/openssl/doc/ssl/SSL_CTX_set_tmp_dh_callback.pod b/crypto/openssl/doc/ssl/SSL_CTX_set_tmp_dh_callback.pod index 29d1f8a6fbfe..7a27eef50b17 100644 --- a/crypto/openssl/doc/ssl/SSL_CTX_set_tmp_dh_callback.pod +++ b/crypto/openssl/doc/ssl/SSL_CTX_set_tmp_dh_callback.pod @@ -12,12 +12,10 @@ SSL_CTX_set_tmp_dh_callback, SSL_CTX_set_tmp_dh, SSL_set_tmp_dh_callback, SSL_se DH *(*tmp_dh_callback)(SSL *ssl, int is_export, int keylength)); long SSL_CTX_set_tmp_dh(SSL_CTX *ctx, DH *dh); - void SSL_set_tmp_dh_callback(SSL_CTX *ctx, + void SSL_set_tmp_dh_callback(SSL *ctx, DH *(*tmp_dh_callback)(SSL *ssl, int is_export, int keylength)); long SSL_set_tmp_dh(SSL *ssl, DH *dh) - DH *(*tmp_dh_callback)(SSL *ssl, int is_export, int keylength)); - =head1 DESCRIPTION SSL_CTX_set_tmp_dh_callback() sets the callback function for B<ctx> to be @@ -50,12 +48,13 @@ even if he gets hold of the normal (certified) key, as this key was only used for signing. In order to perform a DH key exchange the server must use a DH group -(DH parameters) and generate a DH key. The server will always generate a new -DH key during the negotiation, when the DH parameters are supplied via -callback and/or when the SSL_OP_SINGLE_DH_USE option of -L<SSL_CTX_set_options(3)|SSL_CTX_set_options(3)> is set. It will -immediately create a DH key, when DH parameters are supplied via -SSL_CTX_set_tmp_dh() and SSL_OP_SINGLE_DH_USE is not set. In this case, +(DH parameters) and generate a DH key. +The server will always generate a new DH key during the negotiation +if either the DH parameters are supplied via callback or the +SSL_OP_SINGLE_DH_USE option of SSL_CTX_set_options(3) is set (or both). +It will immediately create a DH key if DH parameters are supplied via +SSL_CTX_set_tmp_dh() and SSL_OP_SINGLE_DH_USE is not set. +In this case, it may happen that a key is generated on initialization without later being needed, while on the other hand the computer time during the negotiation is being saved. @@ -81,7 +80,7 @@ instead (see L<dhparam(1)|dhparam(1)>), but in this case SSL_OP_SINGLE_DH_USE is mandatory. Application authors may compile in DH parameters. Files dh512.pem, -dh1024.pem, dh2048.pem, and dh4096 in the 'apps' directory of current +dh1024.pem, dh2048.pem, and dh4096.pem in the 'apps' directory of current version of the OpenSSL distribution contain the 'SKIP' DH parameters, which use safe primes and were generated verifiably pseudo-randomly. These files can be converted into C code using the B<-C> option of the @@ -141,7 +140,7 @@ partly left out.) dh_tmp = dh_512; break; case 1024: - if (!dh_1024) + if (!dh_1024) dh_1024 = get_dh1024(); dh_tmp = dh_1024; break; |