From e1537f951fa87e4d070adda82b474b25cf4902ec Mon Sep 17 00:00:00 2001 From: Damien Miller Date: Tue, 26 Jan 2010 13:26:22 +1100 Subject: - djm@cvs.openbsd.org 2010/01/26 01:28:35 [channels.c channels.h clientloop.c clientloop.h mux.c nchan.c ssh.c] rewrite ssh(1) multiplexing code to a more sensible protocol. The new multiplexing code uses channels for the listener and accepted control sockets to make the mux master non-blocking, so no stalls when processing messages from a slave. avoid use of fatal() in mux master protocol parsing so an errant slave process cannot take down a running master. implement requesting of port-forwards over multiplexed sessions. Any port forwards requested by the slave are added to those the master has established. add support for stdio forwarding ("ssh -W host:port ...") in mux slaves. document master/slave mux protocol so that other tools can use it to control a running ssh(1). Note: there are no guarantees that this protocol won't be incompatibly changed (though it is versioned). feedback Salvador Fandino, dtucker@ channel changes ok markus@ --- nchan.c | 21 +++++++++++++++------ 1 file changed, 15 insertions(+), 6 deletions(-) (limited to 'nchan.c') diff --git a/nchan.c b/nchan.c index 160445e5a..20f6a2f49 100644 --- a/nchan.c +++ b/nchan.c @@ -1,4 +1,4 @@ -/* $OpenBSD: nchan.c,v 1.62 2008/11/07 18:50:18 stevesk Exp $ */ +/* $OpenBSD: nchan.c,v 1.63 2010/01/26 01:28:35 djm Exp $ */ /* * Copyright (c) 1999, 2000, 2001, 2002 Markus Friedl. All rights reserved. * @@ -161,7 +161,7 @@ chan_ibuf_empty(Channel *c) switch (c->istate) { case CHAN_INPUT_WAIT_DRAIN: if (compat20) { - if (!(c->flags & CHAN_CLOSE_SENT)) + if (!(c->flags & (CHAN_CLOSE_SENT|CHAN_LOCAL))) chan_send_eof2(c); chan_set_istate(c, CHAN_INPUT_CLOSED); } else { @@ -278,9 +278,12 @@ static void chan_rcvd_close2(Channel *c) { debug2("channel %d: rcvd close", c->self); - if (c->flags & CHAN_CLOSE_RCVD) - error("channel %d: protocol error: close rcvd twice", c->self); - c->flags |= CHAN_CLOSE_RCVD; + if (!(c->flags & CHAN_LOCAL)) { + if (c->flags & CHAN_CLOSE_RCVD) + error("channel %d: protocol error: close rcvd twice", + c->self); + c->flags |= CHAN_CLOSE_RCVD; + } if (c->type == SSH_CHANNEL_LARVAL) { /* tear down larval channels immediately */ chan_set_ostate(c, CHAN_OUTPUT_CLOSED); @@ -302,11 +305,13 @@ chan_rcvd_close2(Channel *c) chan_set_istate(c, CHAN_INPUT_CLOSED); break; case CHAN_INPUT_WAIT_DRAIN: - chan_send_eof2(c); + if (!(c->flags & CHAN_LOCAL)) + chan_send_eof2(c); chan_set_istate(c, CHAN_INPUT_CLOSED); break; } } + void chan_rcvd_eow(Channel *c) { @@ -454,6 +459,10 @@ chan_is_dead(Channel *c, int do_send) c->self, c->efd, buffer_len(&c->extended)); return 0; } + if (c->flags & CHAN_LOCAL) { + debug2("channel %d: is dead (local)", c->self); + return 1; + } if (!(c->flags & CHAN_CLOSE_SENT)) { if (do_send) { chan_send_close2(c); -- cgit v1.2.3