- dtucker@cvs.openbsd.org 2013/06/07 15:37:52

[channels.c channels.h clientloop.c]
     Add an "ABANDONED" channel state and use for mux sessions that are
     disconnected via the ~. escape sequence.  Channels in this state will
     be able to close if the server responds, but do not count as active channels.
     This means that if you ~. all of the mux clients when using ControlPersist
     on a broken network, the backgrounded mux master will exit when the
     Control Persist time expires rather than hanging around indefinitely.
     bz#1917, also reported and tested by tedu@.  ok djm@ markus@.

ChangeLog

@@ -1,3 +1,15 @@
+20130610
+ - (djm) OpenBSD CVS Sync
+   - dtucker@cvs.openbsd.org 2013/06/07 15:37:52
+     [channels.c channels.h clientloop.c]
+     Add an "ABANDONED" channel state and use for mux sessions that are
+     disconnected via the ~. escape sequence.  Channels in this state will
+     be able to close if the server responds, but do not count as active channels.
+     This means that if you ~. all of the mux clients when using ControlPersist
+     on a broken network, the backgrounded mux master will exit when the
+     Control Persist time expires rather than hanging around indefinitely.
+     bz#1917, also reported and tested by tedu@.  ok djm@ markus@.
+
 20130605
  - (dtucker) [myproposal.h] Enable sha256 kex methods based on the presence of
    the necessary functions, not from the openssl version.

channels.c

@@ -1,4 +1,4 @@
-/* $OpenBSD: channels.c,v 1.322 2013/06/01 13:15:51 dtucker Exp $ */
+/* $OpenBSD: channels.c,v 1.323 2013/06/07 15:37:52 dtucker Exp $ */
 /*
  * Author: Tatu Ylonen <ylo@cs.hut.fi>
  * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
@@ -213,6 +213,7 @@ channel_lookup(int id)
 	case SSH_CHANNEL_OPEN:
 	case SSH_CHANNEL_INPUT_DRAINING:
 	case SSH_CHANNEL_OUTPUT_DRAINING:
+	case SSH_CHANNEL_ABANDONED:
 		return (c);
 	}
 	logit("Non-public channel %d, type %d.", id, c->type);
@@ -530,6 +531,7 @@ channel_still_open(void)
 		case SSH_CHANNEL_DYNAMIC:
 		case SSH_CHANNEL_CONNECTING:
 		case SSH_CHANNEL_ZOMBIE:
+		case SSH_CHANNEL_ABANDONED:
 			continue;
 		case SSH_CHANNEL_LARVAL:
 			if (!compat20)
@@ -575,6 +577,7 @@ channel_find_open(void)
 		case SSH_CHANNEL_OPENING:
 		case SSH_CHANNEL_CONNECTING:
 		case SSH_CHANNEL_ZOMBIE:
+		case SSH_CHANNEL_ABANDONED:
 			continue;
 		case SSH_CHANNEL_LARVAL:
 		case SSH_CHANNEL_AUTH_SOCKET:
@@ -622,6 +625,7 @@ channel_open_message(void)
 		case SSH_CHANNEL_CLOSED:
 		case SSH_CHANNEL_AUTH_SOCKET:
 		case SSH_CHANNEL_ZOMBIE:
+		case SSH_CHANNEL_ABANDONED:
 		case SSH_CHANNEL_MUX_CLIENT:
 		case SSH_CHANNEL_MUX_LISTENER:
 			continue;
@@ -2491,7 +2495,7 @@ channel_input_close_confirmation(int type, u_int32_t seq, void *ctxt)
 	if (c == NULL)
 		packet_disconnect("Received close confirmation for "
 		    "out-of-range channel %d.", id);
-	if (c->type != SSH_CHANNEL_CLOSED)
+	if (c->type != SSH_CHANNEL_CLOSED && c->type != SSH_CHANNEL_ABANDONED)
 		packet_disconnect("Received close confirmation for "
 		    "non-closed channel %d (type %d).", id, c->type);
 	channel_free(c);

channels.h

@@ -1,4 +1,4 @@
-/* $OpenBSD: channels.h,v 1.112 2013/06/02 21:01:51 dtucker Exp $ */
+/* $OpenBSD: channels.h,v 1.113 2013/06/07 15:37:52 dtucker Exp $ */
 
 /*
  * Author: Tatu Ylonen <ylo@cs.hut.fi>
@@ -55,7 +55,8 @@
 #define SSH_CHANNEL_ZOMBIE		14	/* Almost dead. */
 #define SSH_CHANNEL_MUX_LISTENER	15	/* Listener for mux conn. */
 #define SSH_CHANNEL_MUX_CLIENT		16	/* Conn. to mux slave */
-#define SSH_CHANNEL_MAX_TYPE		17
+#define SSH_CHANNEL_ABANDONED		17	/* Abandoned session, eg mux */
+#define SSH_CHANNEL_MAX_TYPE		18
 
 #define CHANNEL_CANCEL_PORT_STATIC	-1
 

clientloop.c

@@ -1,4 +1,4 @@
-/* $OpenBSD: clientloop.c,v 1.252 2013/06/02 23:36:29 dtucker Exp $ */
+/* $OpenBSD: clientloop.c,v 1.253 2013/06/07 15:37:52 dtucker Exp $ */
 /*
  * Author: Tatu Ylonen <ylo@cs.hut.fi>
  * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
@@ -1111,6 +1111,9 @@ process_escapes(Channel *c, Buffer *bin, Buffer *bout, Buffer *berr,
 					chan_write_failed(c);
 					if (c->detach_user)
 						c->detach_user(c->self, NULL);
+					c->type = SSH_CHANNEL_ABANDONED;
+					buffer_clear(&c->input);
+					chan_ibuf_empty(c);
 					return 0;
 				} else
 					quit_pending = 1;