MINOR: ssl: Handle session resumption with TLS 1.3

With TLS 1.3, session aren't established until after the main handshake
has completed. So we can't just rely on calling SSL_get1_session(). Instead,
we now register a callback for the "new session" event. This should work for
previous versions of TLS as well.

diff --git a/src/ssl_sock.c b/src/ssl_sock.c
index 628f4caf0c6f5c65fdd167e917ba471be0faeaa3..818f8ab6f072a4028aa91b7c0d0045f41d0d9cc6 100644 (file)
--- a/src/ssl_sock.c
+++ b/src/ssl_sock.c
@@ -3852,6 +3852,23 @@ static int sh_ssl_sess_store(unsigned char *s_id, unsigned char *data, int data_
        return 1;
 }
 
+/* SSL callback used when a new session is created while connecting to a server */
+static int ssl_sess_new_srv_cb(SSL *ssl, SSL_SESSION *sess)
+{
+       struct connection *conn = SSL_get_app_data(ssl);
+
+       /* check if session was reused, if not store current session on server for reuse */
+       if (objt_server(conn->target)->ssl_ctx.reused_sess[tid]) {
+               SSL_SESSION_free(objt_server(conn->target)->ssl_ctx.reused_sess[tid]);
+               objt_server(conn->target)->ssl_ctx.reused_sess[tid] = NULL;
+       }
+
+       if (!(objt_server(conn->target)->ssl_ctx.options & SRV_SSL_O_NO_REUSE))
+               objt_server(conn->target)->ssl_ctx.reused_sess[tid] = SSL_get1_session(conn->xprt_ctx);
+
+       return 1;
+}
+
 /* SSL callback used on new session creation */
 int sh_ssl_sess_new_cb(SSL *ssl, SSL_SESSION *sess)
 {
@@ -4580,7 +4597,9 @@ int ssl_sock_prepare_srv_ctx(struct server *srv)
 #endif
        }
 
-       SSL_CTX_set_session_cache_mode(srv->ssl_ctx.ctx, SSL_SESS_CACHE_OFF);
+       SSL_CTX_set_session_cache_mode(srv->ssl_ctx.ctx, SSL_SESS_CACHE_CLIENT |
+           SSL_SESS_CACHE_NO_INTERNAL_STORE);
+       SSL_CTX_sess_set_new_cb(srv->ssl_ctx.ctx, ssl_sess_new_srv_cb);
        if (srv->ssl_ctx.ciphers &&
                !SSL_CTX_set_cipher_list(srv->ssl_ctx.ctx, srv->ssl_ctx.ciphers)) {
                Alert("Proxy '%s', server '%s' [%s:%d] : unable to set SSL cipher list to '%s'.\n",
@@ -5208,15 +5227,6 @@ reneg_ok:
                        update_freq_ctr(&global.ssl_be_keys_per_sec, 1);
                        if (global.ssl_be_keys_per_sec.curr_ctr > global.ssl_be_keys_max)
                                global.ssl_be_keys_max = global.ssl_be_keys_per_sec.curr_ctr;
-
-                       /* check if session was reused, if not store current session on server for reuse */
-                       if (objt_server(conn->target)->ssl_ctx.reused_sess[tid]) {
-                               SSL_SESSION_free(objt_server(conn->target)->ssl_ctx.reused_sess[tid]);
-                               objt_server(conn->target)->ssl_ctx.reused_sess[tid] = NULL;
-                       }
-
-                       if (!(objt_server(conn->target)->ssl_ctx.options & SRV_SSL_O_NO_REUSE))
-                               objt_server(conn->target)->ssl_ctx.reused_sess[tid] = SSL_get1_session(conn->xprt_ctx);
                }
                else {
                        update_freq_ctr(&global.ssl_fe_keys_per_sec, 1);