# HG changeset patch
# User Dirkjan Bussink <d.bussink@gmail.com>
# Date 1389366760 -3600
# Node ID d049b0ea00a388c142627f10a0ee01c5b1bedc43
# Parent  4aa64f6950313311e0d322a2af1788edeb7f036c
SSL: ssl_session_tickets directive.

This adds support so it's possible to explicitly disable SSL Session
Tickets. In order to have good Forward Secrecy support either the
session ticket key has to be reloaded by using nginx' binary upgrade
process or using an external key file and reloading the configuration.
This directive adds another possibility to have good support by
disabling session tickets altogether.

If session tickets are enabled and the process lives for a long a time,
an attacker can grab the session ticket from the process and use that to
decrypt any traffic that occured during the entire lifetime of the
process.

diff --git a/src/http/modules/ngx_http_ssl_module.c b/src/http/modules/ngx_http_ssl_module.c
--- a/src/http/modules/ngx_http_ssl_module.c
+++ b/src/http/modules/ngx_http_ssl_module.c
@@ -160,6 +160,13 @@ static ngx_command_t  ngx_http_ssl_comma
       0,
       NULL },
 
+    { ngx_string("ssl_session_tickets"),
+      NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_CONF_FLAG,
+      ngx_conf_set_flag_slot,
+      NGX_HTTP_SRV_CONF_OFFSET,
+      offsetof(ngx_http_ssl_srv_conf_t, session_tickets),
+      NULL },
+
     { ngx_string("ssl_session_ticket_key"),
       NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_CONF_TAKE1,
       ngx_conf_set_str_array_slot,
@@ -436,6 +443,7 @@ ngx_http_ssl_create_srv_conf(ngx_conf_t 
     sscf->verify_depth = NGX_CONF_UNSET_UINT;
     sscf->builtin_session_cache = NGX_CONF_UNSET;
     sscf->session_timeout = NGX_CONF_UNSET;
+    sscf->session_tickets = NGX_CONF_UNSET;
     sscf->session_ticket_keys = NGX_CONF_UNSET_PTR;
     sscf->stapling = NGX_CONF_UNSET;
     sscf->stapling_verify = NGX_CONF_UNSET;
@@ -644,6 +652,14 @@ ngx_http_ssl_merge_srv_conf(ngx_conf_t *
         return NGX_CONF_ERROR;
     }
 
+    ngx_conf_merge_value(conf->session_tickets, prev->session_tickets, 1);
+
+#ifdef SSL_OP_NO_TICKET
+    if (!conf->session_tickets) {
+        SSL_CTX_set_options(conf->ssl.ctx, SSL_OP_NO_TICKET);
+    }
+#endif
+
     ngx_conf_merge_ptr_value(conf->session_ticket_keys,
                          prev->session_ticket_keys, NULL);
 
diff --git a/src/http/modules/ngx_http_ssl_module.h b/src/http/modules/ngx_http_ssl_module.h
--- a/src/http/modules/ngx_http_ssl_module.h
+++ b/src/http/modules/ngx_http_ssl_module.h
@@ -44,6 +44,7 @@ typedef struct {
 
     ngx_shm_zone_t                 *shm_zone;
 
+    ngx_flag_t                      session_tickets;
     ngx_array_t                    *session_ticket_keys;
 
     ngx_flag_t                      stapling;
diff --git a/src/mail/ngx_mail_ssl_module.c b/src/mail/ngx_mail_ssl_module.c
--- a/src/mail/ngx_mail_ssl_module.c
+++ b/src/mail/ngx_mail_ssl_module.c
@@ -116,6 +116,13 @@ static ngx_command_t  ngx_mail_ssl_comma
       0,
       NULL },
 
+    { ngx_string("ssl_session_tickets"),
+      NGX_MAIL_MAIN_CONF|NGX_MAIL_SRV_CONF|NGX_CONF_FLAG,
+      ngx_conf_set_flag_slot,
+      NGX_MAIL_SRV_CONF_OFFSET,
+      offsetof(ngx_mail_ssl_conf_t, session_tickets),
+      NULL },
+
     { ngx_string("ssl_session_ticket_key"),
       NGX_MAIL_MAIN_CONF|NGX_MAIL_SRV_CONF|NGX_CONF_TAKE1,
       ngx_conf_set_str_array_slot,
@@ -191,6 +198,7 @@ ngx_mail_ssl_create_conf(ngx_conf_t *cf)
     scf->prefer_server_ciphers = NGX_CONF_UNSET;
     scf->builtin_session_cache = NGX_CONF_UNSET;
     scf->session_timeout = NGX_CONF_UNSET;
+    scf->session_tickets = NGX_CONF_UNSET;
     scf->session_ticket_keys = NGX_CONF_UNSET_PTR;
 
     return scf;
@@ -339,6 +347,15 @@ ngx_mail_ssl_merge_conf(ngx_conf_t *cf, 
         return NGX_CONF_ERROR;
     }
 
+    ngx_conf_merge_value(conf->session_tickets,
+                         prev->session_tickets, 1);
+
+#ifdef SSL_OP_NO_TICKET
+    if (!conf->session_tickets) {
+        SSL_CTX_set_options(conf->ssl.ctx, SSL_OP_NO_TICKET);
+    }
+#endif
+
     ngx_conf_merge_ptr_value(conf->session_ticket_keys,
                          prev->session_ticket_keys, NULL);
 
diff --git a/src/mail/ngx_mail_ssl_module.h b/src/mail/ngx_mail_ssl_module.h
--- a/src/mail/ngx_mail_ssl_module.h
+++ b/src/mail/ngx_mail_ssl_module.h
@@ -41,6 +41,7 @@ typedef struct {
 
     ngx_shm_zone_t  *shm_zone;
 
+    ngx_flag_t       session_tickets;
     ngx_array_t     *session_ticket_keys;
 
     u_char          *file;