[openssh.git] / nchan.c

/*
 * Copyright (c) 1999 Markus Friedl.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include "includes.h"
RCSID("$OpenBSD: nchan.c,v 1.23 2001/02/28 08:54:55 markus Exp $");

#include "ssh1.h"
#include "ssh2.h"
#include "buffer.h"
#include "packet.h"
#include "channels.h"
#include "nchan.h"
#include "compat.h"
#include "log.h"

/* functions manipulating channel states */
/*
 * EVENTS update channel input/output states execute ACTIONS
 */
/* events concerning the INPUT from socket for channel (istate) */
chan_event_fn *chan_rcvd_oclose			= NULL;
chan_event_fn *chan_read_failed			= NULL;
chan_event_fn *chan_ibuf_empty			= NULL;
/* events concerning the OUTPUT from channel for socket (ostate) */
chan_event_fn *chan_rcvd_ieof			= NULL;
chan_event_fn *chan_write_failed		= NULL;
chan_event_fn *chan_obuf_empty			= NULL;
/*
 * ACTIONS: should never update the channel states
 */
static void	chan_send_ieof1(Channel *c);
static void	chan_send_oclose1(Channel *c);
static void	chan_send_close2(Channel *c);
static void	chan_send_eof2(Channel *c);

/* helper */
static void	chan_shutdown_write(Channel *c);
static void	chan_shutdown_read(Channel *c);

/*
 * SSH1 specific implementation of event functions
 */

static void
chan_rcvd_oclose1(Channel *c)
{
	debug("channel %d: rcvd oclose", c->self);
	switch (c->istate) {
	case CHAN_INPUT_WAIT_OCLOSE:
		debug("channel %d: input wait_oclose -> closed", c->self);
		c->istate = CHAN_INPUT_CLOSED;
		break;
	case CHAN_INPUT_OPEN:
		debug("channel %d: input open -> closed", c->self);
		chan_shutdown_read(c);
		chan_send_ieof1(c);
		c->istate = CHAN_INPUT_CLOSED;
		break;
	case CHAN_INPUT_WAIT_DRAIN:
		/* both local read_failed and remote write_failed  */
		log("channel %d: input drain -> closed", c->self);
		chan_send_ieof1(c);
		c->istate = CHAN_INPUT_CLOSED;
		break;
	default:
		error("channel %d: protocol error: chan_rcvd_oclose for istate %d",
		    c->self, c->istate);
		return;
	}
}
static void
chan_read_failed_12(Channel *c)
{
	debug("channel %d: read failed", c->self);
	switch (c->istate) {
	case CHAN_INPUT_OPEN:
		debug("channel %d: input open -> drain", c->self);
		chan_shutdown_read(c);
		c->istate = CHAN_INPUT_WAIT_DRAIN;
		if (buffer_len(&c->input) == 0) {
			debug("channel %d: input: no drain shortcut", c->self);
			chan_ibuf_empty(c);
		}
		break;
	default:
		error("channel %d: internal error: we do not read, but chan_read_failed for istate %d",
		    c->self, c->istate);
		break;
	}
}
static void
chan_ibuf_empty1(Channel *c)
{
	debug("channel %d: ibuf empty", c->self);
	if (buffer_len(&c->input)) {
		error("channel %d: internal error: chan_ibuf_empty for non empty buffer",
		    c->self);
		return;
	}
	switch (c->istate) {
	case CHAN_INPUT_WAIT_DRAIN:
		debug("channel %d: input drain -> wait_oclose", c->self);
		chan_send_ieof1(c);
		c->istate = CHAN_INPUT_WAIT_OCLOSE;
		break;
	default:
		error("channel %d: internal error: chan_ibuf_empty for istate %d",
		    c->self, c->istate);
		break;
	}
}
static void
chan_rcvd_ieof1(Channel *c)
{
	debug("channel %d: rcvd ieof", c->self);
	if (c->type != SSH_CHANNEL_OPEN) {
		debug("channel %d: non-open", c->self);
		if (c->istate == CHAN_INPUT_OPEN) {
			debug("channel %d: non-open: input open -> wait_oclose", c->self);
			chan_shutdown_read(c);
			chan_send_ieof1(c);
			c->istate = CHAN_INPUT_WAIT_OCLOSE;
		} else {
			error("channel %d: istate %d != open", c->self, c->istate);
		}
		if (c->ostate == CHAN_OUTPUT_OPEN) {
			debug("channel %d: non-open: output open -> closed", c->self);
			chan_send_oclose1(c);
			c->ostate = CHAN_OUTPUT_CLOSED;
		} else {
			error("channel %d: ostate %d != open", c->self, c->ostate);
		}
		return;
	}
	switch (c->ostate) {
	case CHAN_OUTPUT_OPEN:
		debug("channel %d: output open -> drain", c->self);
		c->ostate = CHAN_OUTPUT_WAIT_DRAIN;
		break;
	case CHAN_OUTPUT_WAIT_IEOF:
		debug("channel %d: output wait_ieof -> closed", c->self);
		c->ostate = CHAN_OUTPUT_CLOSED;
		break;
	default:
		error("channel %d: protocol error: chan_rcvd_ieof for ostate %d",
		    c->self, c->ostate);
		break;
	}
}
static void
chan_write_failed1(Channel *c)
{
	debug("channel %d: write failed", c->self);
	switch (c->ostate) {
	case CHAN_OUTPUT_OPEN:
		debug("channel %d: output open -> wait_ieof", c->self);
		chan_send_oclose1(c);
		c->ostate = CHAN_OUTPUT_WAIT_IEOF;
		break;
	case CHAN_OUTPUT_WAIT_DRAIN:
		debug("channel %d: output wait_drain -> closed", c->self);
		chan_send_oclose1(c);
		c->ostate = CHAN_OUTPUT_CLOSED;
		break;
	default:
		error("channel %d: internal error: chan_write_failed for ostate %d",
		    c->self, c->ostate);
		break;
	}
}
static void
chan_obuf_empty1(Channel *c)
{
	debug("channel %d: obuf empty", c->self);
	if (buffer_len(&c->output)) {
		error("channel %d: internal error: chan_obuf_empty for non empty buffer",
		    c->self);
		return;
	}
	switch (c->ostate) {
	case CHAN_OUTPUT_WAIT_DRAIN:
		debug("channel %d: output drain -> closed", c->self);
		chan_send_oclose1(c);
		c->ostate = CHAN_OUTPUT_CLOSED;
		break;
	default:
		error("channel %d: internal error: chan_obuf_empty for ostate %d",
		    c->self, c->ostate);
		break;
	}
}
static void
chan_send_ieof1(Channel *c)
{
	debug("channel %d: send ieof", c->self);
	switch (c->istate) {
	case CHAN_INPUT_OPEN:
	case CHAN_INPUT_WAIT_DRAIN:
		packet_start(SSH_MSG_CHANNEL_INPUT_EOF);
		packet_put_int(c->remote_id);
		packet_send();
		break;
	default:
		error("channel %d: internal error: cannot send ieof for istate %d",
		    c->self, c->istate);
		break;
	}
}
static void
chan_send_oclose1(Channel *c)
{
	debug("channel %d: send oclose", c->self);
	switch (c->ostate) {
	case CHAN_OUTPUT_OPEN:
	case CHAN_OUTPUT_WAIT_DRAIN:
		chan_shutdown_write(c);
		buffer_consume(&c->output, buffer_len(&c->output));
		packet_start(SSH_MSG_CHANNEL_OUTPUT_CLOSE);
		packet_put_int(c->remote_id);
		packet_send();
		break;
	default:
		error("channel %d: internal error: cannot send oclose for ostate %d",
		     c->self, c->ostate);
		break;
	}
}

/*
 * the same for SSH2
 */
static void
chan_rcvd_oclose2(Channel *c)
{
	debug("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->type == SSH_CHANNEL_LARVAL) {
		/* tear down larval channels immediately */
		c->ostate = CHAN_OUTPUT_CLOSED;
		c->istate = CHAN_INPUT_CLOSED;
		return;
	}
	switch (c->ostate) {
	case CHAN_OUTPUT_OPEN:
		/* wait until a data from the channel is consumed if a CLOSE is received */
		debug("channel %d: output open -> drain", c->self);
		c->ostate = CHAN_OUTPUT_WAIT_DRAIN;
		break;
	}
	switch (c->istate) {
	case CHAN_INPUT_OPEN:
		debug("channel %d: input open -> closed", c->self);
		chan_shutdown_read(c);
		break;
	case CHAN_INPUT_WAIT_DRAIN:
		debug("channel %d: input drain -> closed", c->self);
		chan_send_eof2(c);
		break;
	}
	c->istate = CHAN_INPUT_CLOSED;
}
static void
chan_ibuf_empty2(Channel *c)
{
	debug("channel %d: ibuf empty", c->self);
	if (buffer_len(&c->input)) {
		error("channel %d: internal error: chan_ibuf_empty for non empty buffer",
		     c->self);
		return;
	}
	switch (c->istate) {
	case CHAN_INPUT_WAIT_DRAIN:
		debug("channel %d: input drain -> closed", c->self);
		if (!(c->flags & CHAN_CLOSE_SENT))
			chan_send_eof2(c);
		c->istate = CHAN_INPUT_CLOSED;
		break;
	default:
		error("channel %d: internal error: chan_ibuf_empty for istate %d",
		     c->self, c->istate);
		break;
	}
}
static void
chan_rcvd_ieof2(Channel *c)
{
	debug("channel %d: rcvd eof", c->self);
	if (c->ostate == CHAN_OUTPUT_OPEN) {
		debug("channel %d: output open -> drain", c->self);
		c->ostate = CHAN_OUTPUT_WAIT_DRAIN;
	}
}
static void
chan_write_failed2(Channel *c)
{
	debug("channel %d: write failed", c->self);
	switch (c->ostate) {
	case CHAN_OUTPUT_OPEN:
		debug("channel %d: output open -> closed", c->self);
		chan_shutdown_write(c); /* ?? */
		c->ostate = CHAN_OUTPUT_CLOSED;
		break;
	case CHAN_OUTPUT_WAIT_DRAIN:
		debug("channel %d: output drain -> closed", c->self);
		chan_shutdown_write(c);
		c->ostate = CHAN_OUTPUT_CLOSED;
		break;
	default:
		error("channel %d: internal error: chan_write_failed for ostate %d",
		    c->self, c->ostate);
		break;
	}
}
static void
chan_obuf_empty2(Channel *c)
{
	debug("channel %d: obuf empty", c->self);
	if (buffer_len(&c->output)) {
		error("internal error: chan_obuf_empty %d for non empty buffer",
		    c->self);
		return;
	}
	switch (c->ostate) {
	case CHAN_OUTPUT_WAIT_DRAIN:
		debug("channel %d: output drain -> closed", c->self);
		chan_shutdown_write(c);
		c->ostate = CHAN_OUTPUT_CLOSED;
		break;
	default:
		error("channel %d: internal error: chan_obuf_empty for ostate %d",
		    c->self, c->ostate);
		break;
	}
}
static void
chan_send_eof2(Channel *c)
{
	debug("channel %d: send eof", c->self);
	switch (c->istate) {
	case CHAN_INPUT_WAIT_DRAIN:
		packet_start(SSH2_MSG_CHANNEL_EOF);
		packet_put_int(c->remote_id);
		packet_send();
		break;
	default:
		error("channel %d: internal error: cannot send eof for istate %d",
		    c->self, c->istate);
		break;
	}
}
static void
chan_send_close2(Channel *c)
{
	debug("channel %d: send close", c->self);
	if (c->ostate != CHAN_OUTPUT_CLOSED ||
	    c->istate != CHAN_INPUT_CLOSED) {
		error("channel %d: internal error: cannot send close for istate/ostate %d/%d",
		    c->self, c->istate, c->ostate);
	} else if (c->flags & CHAN_CLOSE_SENT) {
		error("channel %d: internal error: already sent close", c->self);
	} else {
		packet_start(SSH2_MSG_CHANNEL_CLOSE);
		packet_put_int(c->remote_id);
		packet_send();
		c->flags |= CHAN_CLOSE_SENT;
	}
}

/* shared */

int
chan_is_dead(Channel *c)
{
	if (c->istate != CHAN_INPUT_CLOSED || c->ostate != CHAN_OUTPUT_CLOSED)
		return 0;
	if (!compat20) {
		debug("channel %d: is dead", c->self);
		return 1;
	}
	/*
	 * we have to delay the close message if the efd (for stderr) is
	 * still active
	 */
	if (((c->extended_usage != CHAN_EXTENDED_IGNORE) &&
	    buffer_len(&c->extended) > 0)
#if 0
	    || ((c->extended_usage == CHAN_EXTENDED_READ) &&
	    c->efd != -1)
#endif
	    ) {
		debug2("channel %d: active efd: %d len %d type %s",
		    c->self, c->efd, buffer_len(&c->extended),
		    c->extended_usage==CHAN_EXTENDED_READ ?
		       "read": "write");
	} else {
		if (!(c->flags & CHAN_CLOSE_SENT)) {
			chan_send_close2(c);
		}
		if ((c->flags & CHAN_CLOSE_SENT) &&
		    (c->flags & CHAN_CLOSE_RCVD)) {
			debug("channel %d: is dead", c->self);
			return 1;
		}
	}
	return 0;
}

void
chan_init_iostates(Channel *c)
{
	c->ostate = CHAN_OUTPUT_OPEN;
	c->istate = CHAN_INPUT_OPEN;
	c->flags = 0;
}

/* init */
void
chan_init(void)
{
	if (compat20) {
		chan_rcvd_oclose		= chan_rcvd_oclose2;
		chan_read_failed		= chan_read_failed_12;
		chan_ibuf_empty			= chan_ibuf_empty2;

		chan_rcvd_ieof			= chan_rcvd_ieof2;
		chan_write_failed		= chan_write_failed2;
		chan_obuf_empty			= chan_obuf_empty2;
	} else {
		chan_rcvd_oclose		= chan_rcvd_oclose1;
		chan_read_failed		= chan_read_failed_12;
		chan_ibuf_empty			= chan_ibuf_empty1;

		chan_rcvd_ieof			= chan_rcvd_ieof1;
		chan_write_failed		= chan_write_failed1;
		chan_obuf_empty			= chan_obuf_empty1;
	}
}

/* helper */
static void
chan_shutdown_write(Channel *c)
{
	buffer_consume(&c->output, buffer_len(&c->output));
	if (compat20 && c->type == SSH_CHANNEL_LARVAL)
		return;
	/* shutdown failure is allowed if write failed already */
	debug("channel %d: close_write", c->self);
	if (c->sock != -1) {
		if (shutdown(c->sock, SHUT_WR) < 0)
			debug("channel %d: chan_shutdown_write: shutdown() failed for fd%d: %.100s",
			    c->self, c->sock, strerror(errno));
	} else {
		if (close(c->wfd) < 0)
			log("channel %d: chan_shutdown_write: close() failed for fd%d: %.100s",
			    c->self, c->wfd, strerror(errno));
		c->wfd = -1;
	}
}
static void
chan_shutdown_read(Channel *c)
{
	if (compat20 && c->type == SSH_CHANNEL_LARVAL)
		return;
	debug("channel %d: close_read", c->self);
	if (c->sock != -1) {
		/*
		 * shutdown(sock, SHUT_READ) may return ENOTCONN if the
		 * write side has been closed already. (bug on Linux)
		 */
		if (shutdown(c->sock, SHUT_RD) < 0
		    && (errno != ENOTCONN
			|| c->ostate == CHAN_OUTPUT_OPEN
			|| c->ostate == CHAN_OUTPUT_WAIT_DRAIN))
			error("channel %d: chan_shutdown_read: shutdown() failed for fd%d [i%d o%d]: %.100s",
			    c->self, c->sock, c->istate, c->ostate, strerror(errno));
	} else {
		if (close(c->rfd) < 0)
			log("channel %d: chan_shutdown_read: close() failed for fd%d: %.100s",
			    c->self, c->rfd, strerror(errno));
		c->rfd = -1;
	}
}
Commit	Line	Data
aa3378df	1	/*
	2	* Copyright (c) 1999 Markus Friedl. All rights reserved.
	3	*
	4	* Redistribution and use in source and binary forms, with or without
	5	* modification, are permitted provided that the following conditions
	6	* are met:
	7	* 1. Redistributions of source code must retain the above copyright
	8	* notice, this list of conditions and the following disclaimer.
	9	* 2. Redistributions in binary form must reproduce the above copyright
	10	* notice, this list of conditions and the following disclaimer in the
	11	* documentation and/or other materials provided with the distribution.
aa3378df	12	*
	13	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
	14	* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
	15	* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
	16	* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
	17	* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
	18	* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
	19	* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
	20	* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
	21	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
	22	* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
	23	*/
	24
8efc0c15	25	#include "includes.h"
ee55dacf	26	RCSID("$OpenBSD: nchan.c,v 1.23 2001/02/28 08:54:55 markus Exp $");
8efc0c15	27
42f11eb2	28	#include "ssh1.h"
42f11eb2	29	#include "ssh2.h"
8efc0c15	30	#include "buffer.h"
	31	#include "packet.h"
	32	#include "channels.h"
	33	#include "nchan.h"
7e7327a1	34	#include "compat.h"
42f11eb2	35	#include "log.h"
8efc0c15	36
7e7327a1	37	/* functions manipulating channel states */
8efc0c15	38	/*
5260325f	39	* EVENTS update channel input/output states execute ACTIONS
8efc0c15	40	*/
8efc0c15	41	/* events concerning the INPUT from socket for channel (istate) */
7e7327a1	42	chan_event_fn *chan_rcvd_oclose = NULL;
	43	chan_event_fn *chan_read_failed = NULL;
	44	chan_event_fn *chan_ibuf_empty = NULL;
	45	/* events concerning the OUTPUT from channel for socket (ostate) */
	46	chan_event_fn *chan_rcvd_ieof = NULL;
	47	chan_event_fn *chan_write_failed = NULL;
	48	chan_event_fn *chan_obuf_empty = NULL;
	49	/*
	50	* ACTIONS: should never update the channel states
	51	*/
	52	static void chan_send_ieof1(Channel *c);
	53	static void chan_send_oclose1(Channel *c);
	54	static void chan_send_close2(Channel *c);
	55	static void chan_send_eof2(Channel *c);
	56
7e7327a1	57	/* helper */
	58	static void chan_shutdown_write(Channel *c);
	59	static void chan_shutdown_read(Channel *c);
	60
	61	/*
	62	* SSH1 specific implementation of event functions
	63	*/
	64
	65	static void
	66	chan_rcvd_oclose1(Channel *c)
5260325f	67	{
7e7327a1	68	debug("channel %d: rcvd oclose", c->self);
5260325f	69	switch (c->istate) {
8efc0c15	70	case CHAN_INPUT_WAIT_OCLOSE:
7e7327a1	71	debug("channel %d: input wait_oclose -> closed", c->self);
5260325f	72	c->istate = CHAN_INPUT_CLOSED;
8efc0c15	73	break;
8efc0c15	74	case CHAN_INPUT_OPEN:
7e7327a1	75	debug("channel %d: input open -> closed", c->self);
8efc0c15	76	chan_shutdown_read(c);
7e7327a1	77	chan_send_ieof1(c);
5260325f	78	c->istate = CHAN_INPUT_CLOSED;
48e671d5	79	break;
	80	case CHAN_INPUT_WAIT_DRAIN:
	81	/* both local read_failed and remote write_failed */
7e7327a1	82	log("channel %d: input drain -> closed", c->self);
7e7327a1	83	chan_send_ieof1(c);
48e671d5	84	c->istate = CHAN_INPUT_CLOSED;
8efc0c15	85	break;
8efc0c15	86	default:
7e7327a1	87	error("channel %d: protocol error: chan_rcvd_oclose for istate %d",
7e7327a1	88	c->self, c->istate);
48e671d5	89	return;
8efc0c15	90	}
8efc0c15	91	}
7e7327a1	92	static void
7e7327a1	93	chan_read_failed_12(Channel *c)
5260325f	94	{
7e7327a1	95	debug("channel %d: read failed", c->self);
5260325f	96	switch (c->istate) {
8efc0c15	97	case CHAN_INPUT_OPEN:
7e7327a1	98	debug("channel %d: input open -> drain", c->self);
8efc0c15	99	chan_shutdown_read(c);
5260325f	100	c->istate = CHAN_INPUT_WAIT_DRAIN;
d0c832f3	101	if (buffer_len(&c->input) == 0) {
	102	debug("channel %d: input: no drain shortcut", c->self);
	103	chan_ibuf_empty(c);
	104	}
8efc0c15	105	break;
8efc0c15	106	default:
7e7327a1	107	error("channel %d: internal error: we do not read, but chan_read_failed for istate %d",
7e7327a1	108	c->self, c->istate);
8efc0c15	109	break;
	110	}
	111	}
7e7327a1	112	static void
7e7327a1	113	chan_ibuf_empty1(Channel *c)
5260325f	114	{
7e7327a1	115	debug("channel %d: ibuf empty", c->self);
5260325f	116	if (buffer_len(&c->input)) {
7e7327a1	117	error("channel %d: internal error: chan_ibuf_empty for non empty buffer",
7e7327a1	118	c->self);
8efc0c15	119	return;
8efc0c15	120	}
5260325f	121	switch (c->istate) {
8efc0c15	122	case CHAN_INPUT_WAIT_DRAIN:
7e7327a1	123	debug("channel %d: input drain -> wait_oclose", c->self);
7e7327a1	124	chan_send_ieof1(c);
5260325f	125	c->istate = CHAN_INPUT_WAIT_OCLOSE;
8efc0c15	126	break;
8efc0c15	127	default:
7e7327a1	128	error("channel %d: internal error: chan_ibuf_empty for istate %d",
7e7327a1	129	c->self, c->istate);
8efc0c15	130	break;
	131	}
	132	}
7e7327a1	133	static void
7e7327a1	134	chan_rcvd_ieof1(Channel *c)
5260325f	135	{
7e7327a1	136	debug("channel %d: rcvd ieof", c->self);
1d1ffb87	137	if (c->type != SSH_CHANNEL_OPEN) {
	138	debug("channel %d: non-open", c->self);
	139	if (c->istate == CHAN_INPUT_OPEN) {
	140	debug("channel %d: non-open: input open -> wait_oclose", c->self);
	141	chan_shutdown_read(c);
	142	chan_send_ieof1(c);
	143	c->istate = CHAN_INPUT_WAIT_OCLOSE;
	144	} else {
	145	error("channel %d: istate %d != open", c->self, c->istate);
	146	}
	147	if (c->ostate == CHAN_OUTPUT_OPEN) {
	148	debug("channel %d: non-open: output open -> closed", c->self);
	149	chan_send_oclose1(c);
	150	c->ostate = CHAN_OUTPUT_CLOSED;
	151	} else {
	152	error("channel %d: ostate %d != open", c->self, c->ostate);
	153	}
	154	return;
	155	}
5260325f	156	switch (c->ostate) {
8efc0c15	157	case CHAN_OUTPUT_OPEN:
7e7327a1	158	debug("channel %d: output open -> drain", c->self);
5260325f	159	c->ostate = CHAN_OUTPUT_WAIT_DRAIN;
8efc0c15	160	break;
8efc0c15	161	case CHAN_OUTPUT_WAIT_IEOF:
7e7327a1	162	debug("channel %d: output wait_ieof -> closed", c->self);
5260325f	163	c->ostate = CHAN_OUTPUT_CLOSED;
8efc0c15	164	break;
8efc0c15	165	default:
7e7327a1	166	error("channel %d: protocol error: chan_rcvd_ieof for ostate %d",
7e7327a1	167	c->self, c->ostate);
8efc0c15	168	break;
	169	}
	170	}
7e7327a1	171	static void
7e7327a1	172	chan_write_failed1(Channel *c)
5260325f	173	{
7e7327a1	174	debug("channel %d: write failed", c->self);
5260325f	175	switch (c->ostate) {
8efc0c15	176	case CHAN_OUTPUT_OPEN:
7e7327a1	177	debug("channel %d: output open -> wait_ieof", c->self);
7e7327a1	178	chan_send_oclose1(c);
5260325f	179	c->ostate = CHAN_OUTPUT_WAIT_IEOF;
8efc0c15	180	break;
8efc0c15	181	case CHAN_OUTPUT_WAIT_DRAIN:
7e7327a1	182	debug("channel %d: output wait_drain -> closed", c->self);
7e7327a1	183	chan_send_oclose1(c);
5260325f	184	c->ostate = CHAN_OUTPUT_CLOSED;
8efc0c15	185	break;
8efc0c15	186	default:
7e7327a1	187	error("channel %d: internal error: chan_write_failed for ostate %d",
7e7327a1	188	c->self, c->ostate);
8efc0c15	189	break;
	190	}
	191	}
7e7327a1	192	static void
7e7327a1	193	chan_obuf_empty1(Channel *c)
5260325f	194	{
7e7327a1	195	debug("channel %d: obuf empty", c->self);
5260325f	196	if (buffer_len(&c->output)) {
7e7327a1	197	error("channel %d: internal error: chan_obuf_empty for non empty buffer",
7e7327a1	198	c->self);
8efc0c15	199	return;
8efc0c15	200	}
5260325f	201	switch (c->ostate) {
8efc0c15	202	case CHAN_OUTPUT_WAIT_DRAIN:
7e7327a1	203	debug("channel %d: output drain -> closed", c->self);
7e7327a1	204	chan_send_oclose1(c);
5260325f	205	c->ostate = CHAN_OUTPUT_CLOSED;
8efc0c15	206	break;
8efc0c15	207	default:
7e7327a1	208	error("channel %d: internal error: chan_obuf_empty for ostate %d",
7e7327a1	209	c->self, c->ostate);
8efc0c15	210	break;
	211	}
	212	}
8efc0c15	213	static void
7e7327a1	214	chan_send_ieof1(Channel *c)
5260325f	215	{
7e7327a1	216	debug("channel %d: send ieof", c->self);
5260325f	217	switch (c->istate) {
8efc0c15	218	case CHAN_INPUT_OPEN:
	219	case CHAN_INPUT_WAIT_DRAIN:
	220	packet_start(SSH_MSG_CHANNEL_INPUT_EOF);
	221	packet_put_int(c->remote_id);
	222	packet_send();
	223	break;
	224	default:
7e7327a1	225	error("channel %d: internal error: cannot send ieof for istate %d",
7e7327a1	226	c->self, c->istate);
8efc0c15	227	break;
	228	}
	229	}
	230	static void
7e7327a1	231	chan_send_oclose1(Channel *c)
5260325f	232	{
7e7327a1	233	debug("channel %d: send oclose", c->self);
5260325f	234	switch (c->ostate) {
8efc0c15	235	case CHAN_OUTPUT_OPEN:
	236	case CHAN_OUTPUT_WAIT_DRAIN:
	237	chan_shutdown_write(c);
	238	buffer_consume(&c->output, buffer_len(&c->output));
	239	packet_start(SSH_MSG_CHANNEL_OUTPUT_CLOSE);
	240	packet_put_int(c->remote_id);
	241	packet_send();
	242	break;
	243	default:
7e7327a1	244	error("channel %d: internal error: cannot send oclose for ostate %d",
7e7327a1	245	c->self, c->ostate);
8efc0c15	246	break;
	247	}
	248	}
5260325f	249
7e7327a1	250	/*
	251	* the same for SSH2
	252	*/
8efc0c15	253	static void
7e7327a1	254	chan_rcvd_oclose2(Channel *c)
5260325f	255	{
7e7327a1	256	debug("channel %d: rcvd close", c->self);
	257	if (c->flags & CHAN_CLOSE_RCVD)
	258	error("channel %d: protocol error: close rcvd twice", c->self);
	259	c->flags \|= CHAN_CLOSE_RCVD;
	260	if (c->type == SSH_CHANNEL_LARVAL) {
	261	/* tear down larval channels immediately */
	262	c->ostate = CHAN_OUTPUT_CLOSED;
	263	c->istate = CHAN_INPUT_CLOSED;
	264	return;
	265	}
	266	switch (c->ostate) {
	267	case CHAN_OUTPUT_OPEN:
	268	/* wait until a data from the channel is consumed if a CLOSE is received */
	269	debug("channel %d: output open -> drain", c->self);
	270	c->ostate = CHAN_OUTPUT_WAIT_DRAIN;
	271	break;
	272	}
	273	switch (c->istate) {
	274	case CHAN_INPUT_OPEN:
	275	debug("channel %d: input open -> closed", c->self);
	276	chan_shutdown_read(c);
	277	break;
	278	case CHAN_INPUT_WAIT_DRAIN:
	279	debug("channel %d: input drain -> closed", c->self);
	280	chan_send_eof2(c);
	281	break;
	282	}
	283	c->istate = CHAN_INPUT_CLOSED;
8efc0c15	284	}
8efc0c15	285	static void
7e7327a1	286	chan_ibuf_empty2(Channel *c)
	287	{
	288	debug("channel %d: ibuf empty", c->self);
	289	if (buffer_len(&c->input)) {
	290	error("channel %d: internal error: chan_ibuf_empty for non empty buffer",
	291	c->self);
	292	return;
	293	}
	294	switch (c->istate) {
	295	case CHAN_INPUT_WAIT_DRAIN:
	296	debug("channel %d: input drain -> closed", c->self);
	297	if (!(c->flags & CHAN_CLOSE_SENT))
	298	chan_send_eof2(c);
	299	c->istate = CHAN_INPUT_CLOSED;
	300	break;
	301	default:
	302	error("channel %d: internal error: chan_ibuf_empty for istate %d",
	303	c->self, c->istate);
	304	break;
	305	}
	306	}
	307	static void
	308	chan_rcvd_ieof2(Channel *c)
5260325f	309	{
7e7327a1	310	debug("channel %d: rcvd eof", c->self);
	311	if (c->ostate == CHAN_OUTPUT_OPEN) {
	312	debug("channel %d: output open -> drain", c->self);
	313	c->ostate = CHAN_OUTPUT_WAIT_DRAIN;
	314	}
8efc0c15	315	}
7e7327a1	316	static void
	317	chan_write_failed2(Channel *c)
	318	{
	319	debug("channel %d: write failed", c->self);
	320	switch (c->ostate) {
	321	case CHAN_OUTPUT_OPEN:
	322	debug("channel %d: output open -> closed", c->self);
1d1ffb87	323	chan_shutdown_write(c); /* ?? */
7e7327a1	324	c->ostate = CHAN_OUTPUT_CLOSED;
	325	break;
	326	case CHAN_OUTPUT_WAIT_DRAIN:
	327	debug("channel %d: output drain -> closed", c->self);
	328	chan_shutdown_write(c);
	329	c->ostate = CHAN_OUTPUT_CLOSED;
	330	break;
	331	default:
	332	error("channel %d: internal error: chan_write_failed for ostate %d",
	333	c->self, c->ostate);
	334	break;
	335	}
	336	}
	337	static void
	338	chan_obuf_empty2(Channel *c)
	339	{
	340	debug("channel %d: obuf empty", c->self);
	341	if (buffer_len(&c->output)) {
	342	error("internal error: chan_obuf_empty %d for non empty buffer",
	343	c->self);
	344	return;
	345	}
	346	switch (c->ostate) {
	347	case CHAN_OUTPUT_WAIT_DRAIN:
	348	debug("channel %d: output drain -> closed", c->self);
	349	chan_shutdown_write(c);
	350	c->ostate = CHAN_OUTPUT_CLOSED;
	351	break;
	352	default:
	353	error("channel %d: internal error: chan_obuf_empty for ostate %d",
	354	c->self, c->ostate);
	355	break;
	356	}
	357	}
	358	static void
	359	chan_send_eof2(Channel *c)
	360	{
	361	debug("channel %d: send eof", c->self);
	362	switch (c->istate) {
	363	case CHAN_INPUT_WAIT_DRAIN:
	364	packet_start(SSH2_MSG_CHANNEL_EOF);
	365	packet_put_int(c->remote_id);
	366	packet_send();
	367	break;
	368	default:
	369	error("channel %d: internal error: cannot send eof for istate %d",
	370	c->self, c->istate);
	371	break;
	372	}
	373	}
	374	static void
	375	chan_send_close2(Channel *c)
	376	{
	377	debug("channel %d: send close", c->self);
	378	if (c->ostate != CHAN_OUTPUT_CLOSED \|\|
	379	c->istate != CHAN_INPUT_CLOSED) {
	380	error("channel %d: internal error: cannot send close for istate/ostate %d/%d",
	381	c->self, c->istate, c->ostate);
	382	} else if (c->flags & CHAN_CLOSE_SENT) {
	383	error("channel %d: internal error: already sent close", c->self);
	384	} else {
	385	packet_start(SSH2_MSG_CHANNEL_CLOSE);
	386	packet_put_int(c->remote_id);
	387	packet_send();
388	c->flags \|= CHAN_CLOSE_SENT;
389	}
390	}
ee55dacf	391
	392	/* shared */
	393
	394	int
	395	chan_is_dead(Channel *c)
5260325f	396	{
ee55dacf	397	if (c->istate != CHAN_INPUT_CLOSED \|\| c->ostate != CHAN_OUTPUT_CLOSED)
	398	return 0;
	399	if (!compat20) {
	400	debug("channel %d: is dead", c->self);
	401	return 1;
	402	}
	403	/*
	404	* we have to delay the close message if the efd (for stderr) is
	405	* still active
	406	*/
	407	if (((c->extended_usage != CHAN_EXTENDED_IGNORE) &&
	408	buffer_len(&c->extended) > 0)
	409	#if 0
	410	\|\| ((c->extended_usage == CHAN_EXTENDED_READ) &&
	411	c->efd != -1)
	412	#endif
	413	) {
	414	debug2("channel %d: active efd: %d len %d type %s",
	415	c->self, c->efd, buffer_len(&c->extended),
	416	c->extended_usage==CHAN_EXTENDED_READ ?
	417	"read": "write");
	418	} else {
7e7327a1	419	if (!(c->flags & CHAN_CLOSE_SENT)) {
	420	chan_send_close2(c);
	421	}
6ae2364d	422	if ((c->flags & CHAN_CLOSE_SENT) &&
7e7327a1	423	(c->flags & CHAN_CLOSE_RCVD)) {
ee55dacf	424	debug("channel %d: is dead", c->self);
ee55dacf	425	return 1;
6ae2364d	426	}
8efc0c15	427	}
ee55dacf	428	return 0;
8efc0c15	429	}
7e7327a1	430
8efc0c15	431	void
5260325f	432	chan_init_iostates(Channel *c)
	433	{
	434	c->ostate = CHAN_OUTPUT_OPEN;
	435	c->istate = CHAN_INPUT_OPEN;
7e7327a1	436	c->flags = 0;
	437	}
	438
	439	/* init */
	440	void
	441	chan_init(void)
	442	{
	443	if (compat20) {
	444	chan_rcvd_oclose = chan_rcvd_oclose2;
	445	chan_read_failed = chan_read_failed_12;
	446	chan_ibuf_empty = chan_ibuf_empty2;
	447
	448	chan_rcvd_ieof = chan_rcvd_ieof2;
	449	chan_write_failed = chan_write_failed2;
	450	chan_obuf_empty = chan_obuf_empty2;
7e7327a1	451	} else {
	452	chan_rcvd_oclose = chan_rcvd_oclose1;
	453	chan_read_failed = chan_read_failed_12;
	454	chan_ibuf_empty = chan_ibuf_empty1;
	455
	456	chan_rcvd_ieof = chan_rcvd_ieof1;
	457	chan_write_failed = chan_write_failed1;
	458	chan_obuf_empty = chan_obuf_empty1;
7e7327a1	459	}
	460	}
	461
	462	/* helper */
	463	static void
	464	chan_shutdown_write(Channel *c)
	465	{
	466	buffer_consume(&c->output, buffer_len(&c->output));
	467	if (compat20 && c->type == SSH_CHANNEL_LARVAL)
	468	return;
	469	/* shutdown failure is allowed if write failed already */
	470	debug("channel %d: close_write", c->self);
	471	if (c->sock != -1) {
	472	if (shutdown(c->sock, SHUT_WR) < 0)
	473	debug("channel %d: chan_shutdown_write: shutdown() failed for fd%d: %.100s",
	474	c->self, c->sock, strerror(errno));
	475	} else {
	476	if (close(c->wfd) < 0)
	477	log("channel %d: chan_shutdown_write: close() failed for fd%d: %.100s",
	478	c->self, c->wfd, strerror(errno));
	479	c->wfd = -1;
	480	}
	481	}
	482	static void
	483	chan_shutdown_read(Channel *c)
	484	{
	485	if (compat20 && c->type == SSH_CHANNEL_LARVAL)
	486	return;
	487	debug("channel %d: close_read", c->self);
	488	if (c->sock != -1) {
2b87da3b	489	/*
47670e77	490	* shutdown(sock, SHUT_READ) may return ENOTCONN if the
	491	* write side has been closed already. (bug on Linux)
	492	*/
	493	if (shutdown(c->sock, SHUT_RD) < 0
	494	&& (errno != ENOTCONN
	495	\|\| c->ostate == CHAN_OUTPUT_OPEN
	496	\|\| c->ostate == CHAN_OUTPUT_WAIT_DRAIN))
7e7327a1	497	error("channel %d: chan_shutdown_read: shutdown() failed for fd%d [i%d o%d]: %.100s",
	498	c->self, c->sock, c->istate, c->ostate, strerror(errno));
	499	} else {
	500	if (close(c->rfd) < 0)
	501	log("channel %d: chan_shutdown_read: close() failed for fd%d: %.100s",
	502	c->self, c->rfd, strerror(errno));
	503	c->rfd = -1;
	504	}
8efc0c15	505	}