MSIE export versions are rare now, so RSA 512 key is generated on demand

and is shared among all hosts instead of pregenerating for every HTTPS host
on configuraiton phase. This decreases start time for configuration with
large number of HTTPS hosts.

4 files changed, 11 insertions, 25 deletions

diff --git a/src/event/ngx_event_openssl.c b/src/event/ngx_event_openssl.c
index 0527c9c30..a12672583 100644
--- a/src/event/ngx_event_openssl.c
+++ b/src/event/ngx_event_openssl.c
@@ -371,28 +371,18 @@ ngx_ssl_info_callback(const ngx_ssl_conn_t *ssl_conn, int where, int ret)
 }
 
 
-ngx_int_t
-ngx_ssl_generate_rsa512_key(ngx_ssl_t *ssl)
+RSA *
+ngx_ssl_rsa512_key_callback(SSL *ssl, int is_export, int key_length)
 {
-    RSA  *key;
-
-    if (SSL_CTX_need_tmp_RSA(ssl->ctx) == 0) {
-        return NGX_OK;
-    }
-
-    key = RSA_generate_key(512, RSA_F4, NULL, NULL);
-
-    if (key) {
-        SSL_CTX_set_tmp_rsa(ssl->ctx, key);
+    static RSA  *key;
 
-        RSA_free(key);
-
-        return NGX_OK;
+    if (key_length == 512) {
+        if (key == NULL) {
+            key = RSA_generate_key(512, RSA_F4, NULL, NULL);
+        }
     }
 
-    ngx_ssl_error(NGX_LOG_EMERG, ssl->log, 0, "RSA_generate_key(512) failed");
-
-    return NGX_ERROR;
+    return key;
 }
 
 
diff --git a/src/event/ngx_event_openssl.h b/src/event/ngx_event_openssl.h
index a8f9d8757..d564e5d9b 100644
--- a/src/event/ngx_event_openssl.h
+++ b/src/event/ngx_event_openssl.h
@@ -99,7 +99,7 @@ ngx_int_t ngx_ssl_certificate(ngx_conf_t *cf, ngx_ssl_t *ssl,
 ngx_int_t ngx_ssl_client_certificate(ngx_conf_t *cf, ngx_ssl_t *ssl,
     ngx_str_t *cert, ngx_int_t depth);
 ngx_int_t ngx_ssl_crl(ngx_conf_t *cf, ngx_ssl_t *ssl, ngx_str_t *crl);
-ngx_int_t ngx_ssl_generate_rsa512_key(ngx_ssl_t *ssl);
+RSA *ngx_ssl_rsa512_key_callback(SSL *ssl, int is_export, int key_length);
 ngx_int_t ngx_ssl_dhparam(ngx_conf_t *cf, ngx_ssl_t *ssl, ngx_str_t *file);
 ngx_int_t ngx_ssl_session_cache(ngx_ssl_t *ssl, ngx_str_t *sess_ctx,
     ssize_t builtin_session_cache, ngx_shm_zone_t *shm_zone, time_t timeout);
diff --git a/src/http/modules/ngx_http_ssl_module.c b/src/http/modules/ngx_http_ssl_module.c
index 1860050d3..52c9196ce 100644
--- a/src/http/modules/ngx_http_ssl_module.c
+++ b/src/http/modules/ngx_http_ssl_module.c
@@ -465,9 +465,7 @@ ngx_http_ssl_merge_srv_conf(ngx_conf_t *cf, void *parent, void *child)
     }
 
     /* a temporary 512-bit RSA key is required for export versions of MSIE */
-    if (ngx_ssl_generate_rsa512_key(&conf->ssl) != NGX_OK) {
-        return NGX_CONF_ERROR;
-    }
+    SSL_CTX_set_tmp_rsa_callback(conf->ssl.ctx, ngx_ssl_rsa512_key_callback);
 
     if (ngx_ssl_dhparam(cf, &conf->ssl, &conf->dhparam) != NGX_OK) {
         return NGX_CONF_ERROR;
diff --git a/src/mail/ngx_mail_ssl_module.c b/src/mail/ngx_mail_ssl_module.c
index 9dd9dfd15..da91d37ce 100644
--- a/src/mail/ngx_mail_ssl_module.c
+++ b/src/mail/ngx_mail_ssl_module.c
@@ -286,9 +286,7 @@ ngx_mail_ssl_merge_conf(ngx_conf_t *cf, void *parent, void *child)
         SSL_CTX_set_options(conf->ssl.ctx, SSL_OP_CIPHER_SERVER_PREFERENCE);
     }
 
-    if (ngx_ssl_generate_rsa512_key(&conf->ssl) != NGX_OK) {
-        return NGX_CONF_ERROR;
-    }
+    SSL_CTX_set_tmp_rsa_callback(conf->ssl.ctx, ngx_ssl_rsa512_key_callback);
 
     if (ngx_ssl_dhparam(cf, &conf->ssl, &conf->dhparam) != NGX_OK) {
         return NGX_CONF_ERROR;