- djm@cvs.openbsd.org 2008/06/12 04:06:00
[clientloop.h ssh.c clientloop.c]
maintain an ordered queue of outstanding global requests that we
expect replies to, similar to the per-channel confirmation queue.
Use this queue to verify success or failure for remote forward
establishment in a race free way.
ok dtucker@
diff --git a/clientloop.c b/clientloop.c
index b45e729..37cecf5 100644
--- a/clientloop.c
+++ b/clientloop.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: clientloop.c,v 1.195 2008/06/12 03:40:52 djm Exp $ */
+/* $OpenBSD: clientloop.c,v 1.196 2008/06/12 04:06:00 djm Exp $ */
/*
* Author: Tatu Ylonen <ylo@cs.hut.fi>
* Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
@@ -174,6 +174,17 @@
int id, do_close;
};
+/* Global request success/failure callbacks */
+struct global_confirm {
+ TAILQ_ENTRY(global_confirm) entry;
+ global_confirm_cb *cb;
+ void *ctx;
+ int ref_count;
+};
+TAILQ_HEAD(global_confirms, global_confirm);
+static struct global_confirms global_confirms =
+ TAILQ_HEAD_INITIALIZER(global_confirms);
+
/*XXX*/
extern Kex *xxx_kex;
@@ -468,8 +479,19 @@
static void
client_global_request_reply(int type, u_int32_t seq, void *ctxt)
{
+ struct global_confirm *gc;
+
+ if ((gc = TAILQ_FIRST(&global_confirms)) == NULL)
+ return;
+ if (gc->cb != NULL)
+ gc->cb(type, seq, gc->ctx);
+ if (--gc->ref_count <= 0) {
+ TAILQ_REMOVE(&global_confirms, gc, entry);
+ bzero(gc, sizeof(*gc));
+ xfree(gc);
+ }
+
keep_alive_timeouts = 0;
- client_global_request_reply_fwd(type, seq, ctxt);
}
static void
@@ -483,6 +505,8 @@
packet_put_cstring("keepalive@openssh.com");
packet_put_char(1); /* boolean: want reply */
packet_send();
+ /* Insert an empty placeholder to maintain ordering */
+ client_register_global_confirm(NULL, NULL);
}
/*
@@ -702,6 +726,27 @@
client_abandon_status_confirm, cr);
}
+void
+client_register_global_confirm(global_confirm_cb *cb, void *ctx)
+{
+ struct global_confirm *gc, *first_gc;
+
+ /* Coalesce identical callbacks */
+ first_gc = TAILQ_FIRST(&global_confirms);
+ if (first_gc && first_gc->cb == cb && first_gc->ctx == ctx) {
+ if (++first_gc->ref_count >= INT_MAX)
+ fatal("%s: first_gc->ref_count = %d",
+ __func__, first_gc->ref_count);
+ return;
+ }
+
+ gc = xmalloc(sizeof(*gc));
+ gc->cb = cb;
+ gc->ctx = ctx;
+ gc->ref_count = 1;
+ TAILQ_INSERT_TAIL(&global_confirms, gc, entry);
+}
+
static void
process_cmdline(void)
{