[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 1.22 2001/01/21 19:05:52 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);

/* channel cleanup */
chan_event_fn *chan_delete_if_full_closed	= NULL;

/* 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;
	}
}
static void
chan_delete_if_full_closed1(Channel *c)
{
	debug3("channel %d: chan_delete_if_full_closed1: istate %d ostate %d",
	    c->self, c->istate, c->ostate);
	if (c->istate == CHAN_INPUT_CLOSED && c->ostate == CHAN_OUTPUT_CLOSED) {
		debug("channel %d: full closed", c->self);
		channel_free(c->self);
	}
}

/*
 * 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;
	}
}
static void
chan_delete_if_full_closed2(Channel *c)
{
	debug3("channel %d: chan_delete_if_full_closed2: istate %d ostate %d",
	    c->self, c->istate, c->ostate);
	if (c->istate == CHAN_INPUT_CLOSED && c->ostate == CHAN_OUTPUT_CLOSED) {
		if (!(c->flags & CHAN_CLOSE_SENT)) {
			chan_send_close2(c);
		}
		if ((c->flags & CHAN_CLOSE_SENT) &&
		    (c->flags & CHAN_CLOSE_RCVD)) {
			debug("channel %d: full closed2", c->self);
			channel_free(c->self);
		}
	}
}

/* shared */
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;

		chan_delete_if_full_closed	= chan_delete_if_full_closed2;
	} 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;

		chan_delete_if_full_closed	= chan_delete_if_full_closed1;
	}
}

/* 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"
42f11eb2	26	RCSID("$OpenBSD: nchan.c,v 1.22 2001/01/21 19:05:52 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
	57	/* channel cleanup */
	58	chan_event_fn *chan_delete_if_full_closed = NULL;
	59
	60	/* helper */
	61	static void chan_shutdown_write(Channel *c);
	62	static void chan_shutdown_read(Channel *c);
	63
	64	/*
	65	* SSH1 specific implementation of event functions
	66	*/
	67
	68	static void
	69	chan_rcvd_oclose1(Channel *c)
5260325f	70	{
7e7327a1	71	debug("channel %d: rcvd oclose", c->self);
5260325f	72	switch (c->istate) {
8efc0c15	73	case CHAN_INPUT_WAIT_OCLOSE:
7e7327a1	74	debug("channel %d: input wait_oclose -> closed", c->self);
5260325f	75	c->istate = CHAN_INPUT_CLOSED;
8efc0c15	76	break;
8efc0c15	77	case CHAN_INPUT_OPEN:
7e7327a1	78	debug("channel %d: input open -> closed", c->self);
8efc0c15	79	chan_shutdown_read(c);
7e7327a1	80	chan_send_ieof1(c);
5260325f	81	c->istate = CHAN_INPUT_CLOSED;
48e671d5	82	break;
	83	case CHAN_INPUT_WAIT_DRAIN:
	84	/* both local read_failed and remote write_failed */
7e7327a1	85	log("channel %d: input drain -> closed", c->self);
7e7327a1	86	chan_send_ieof1(c);
48e671d5	87	c->istate = CHAN_INPUT_CLOSED;
8efc0c15	88	break;
8efc0c15	89	default:
7e7327a1	90	error("channel %d: protocol error: chan_rcvd_oclose for istate %d",
7e7327a1	91	c->self, c->istate);
48e671d5	92	return;
8efc0c15	93	}
8efc0c15	94	}
7e7327a1	95	static void
7e7327a1	96	chan_read_failed_12(Channel *c)
5260325f	97	{
7e7327a1	98	debug("channel %d: read failed", c->self);
5260325f	99	switch (c->istate) {
8efc0c15	100	case CHAN_INPUT_OPEN:
7e7327a1	101	debug("channel %d: input open -> drain", c->self);
8efc0c15	102	chan_shutdown_read(c);
5260325f	103	c->istate = CHAN_INPUT_WAIT_DRAIN;
d0c832f3	104	if (buffer_len(&c->input) == 0) {
	105	debug("channel %d: input: no drain shortcut", c->self);
	106	chan_ibuf_empty(c);
	107	}
8efc0c15	108	break;
8efc0c15	109	default:
7e7327a1	110	error("channel %d: internal error: we do not read, but chan_read_failed for istate %d",
7e7327a1	111	c->self, c->istate);
8efc0c15	112	break;
	113	}
	114	}
7e7327a1	115	static void
7e7327a1	116	chan_ibuf_empty1(Channel *c)
5260325f	117	{
7e7327a1	118	debug("channel %d: ibuf empty", c->self);
5260325f	119	if (buffer_len(&c->input)) {
7e7327a1	120	error("channel %d: internal error: chan_ibuf_empty for non empty buffer",
7e7327a1	121	c->self);
8efc0c15	122	return;
8efc0c15	123	}
5260325f	124	switch (c->istate) {
8efc0c15	125	case CHAN_INPUT_WAIT_DRAIN:
7e7327a1	126	debug("channel %d: input drain -> wait_oclose", c->self);
7e7327a1	127	chan_send_ieof1(c);
5260325f	128	c->istate = CHAN_INPUT_WAIT_OCLOSE;
8efc0c15	129	break;
8efc0c15	130	default:
7e7327a1	131	error("channel %d: internal error: chan_ibuf_empty for istate %d",
7e7327a1	132	c->self, c->istate);
8efc0c15	133	break;
	134	}
	135	}
7e7327a1	136	static void
7e7327a1	137	chan_rcvd_ieof1(Channel *c)
5260325f	138	{
7e7327a1	139	debug("channel %d: rcvd ieof", c->self);
1d1ffb87	140	if (c->type != SSH_CHANNEL_OPEN) {
	141	debug("channel %d: non-open", c->self);
	142	if (c->istate == CHAN_INPUT_OPEN) {
	143	debug("channel %d: non-open: input open -> wait_oclose", c->self);
	144	chan_shutdown_read(c);
	145	chan_send_ieof1(c);
	146	c->istate = CHAN_INPUT_WAIT_OCLOSE;
	147	} else {
	148	error("channel %d: istate %d != open", c->self, c->istate);
	149	}
	150	if (c->ostate == CHAN_OUTPUT_OPEN) {
	151	debug("channel %d: non-open: output open -> closed", c->self);
	152	chan_send_oclose1(c);
	153	c->ostate = CHAN_OUTPUT_CLOSED;
	154	} else {
	155	error("channel %d: ostate %d != open", c->self, c->ostate);
	156	}
	157	return;
	158	}
5260325f	159	switch (c->ostate) {
8efc0c15	160	case CHAN_OUTPUT_OPEN:
7e7327a1	161	debug("channel %d: output open -> drain", c->self);
5260325f	162	c->ostate = CHAN_OUTPUT_WAIT_DRAIN;
8efc0c15	163	break;
8efc0c15	164	case CHAN_OUTPUT_WAIT_IEOF:
7e7327a1	165	debug("channel %d: output wait_ieof -> closed", c->self);
5260325f	166	c->ostate = CHAN_OUTPUT_CLOSED;
8efc0c15	167	break;
8efc0c15	168	default:
7e7327a1	169	error("channel %d: protocol error: chan_rcvd_ieof for ostate %d",
7e7327a1	170	c->self, c->ostate);
8efc0c15	171	break;
	172	}
	173	}
7e7327a1	174	static void
7e7327a1	175	chan_write_failed1(Channel *c)
5260325f	176	{
7e7327a1	177	debug("channel %d: write failed", c->self);
5260325f	178	switch (c->ostate) {
8efc0c15	179	case CHAN_OUTPUT_OPEN:
7e7327a1	180	debug("channel %d: output open -> wait_ieof", c->self);
7e7327a1	181	chan_send_oclose1(c);
5260325f	182	c->ostate = CHAN_OUTPUT_WAIT_IEOF;
8efc0c15	183	break;
8efc0c15	184	case CHAN_OUTPUT_WAIT_DRAIN:
7e7327a1	185	debug("channel %d: output wait_drain -> closed", c->self);
7e7327a1	186	chan_send_oclose1(c);
5260325f	187	c->ostate = CHAN_OUTPUT_CLOSED;
8efc0c15	188	break;
8efc0c15	189	default:
7e7327a1	190	error("channel %d: internal error: chan_write_failed for ostate %d",
7e7327a1	191	c->self, c->ostate);
8efc0c15	192	break;
	193	}
	194	}
7e7327a1	195	static void
7e7327a1	196	chan_obuf_empty1(Channel *c)
5260325f	197	{
7e7327a1	198	debug("channel %d: obuf empty", c->self);
5260325f	199	if (buffer_len(&c->output)) {
7e7327a1	200	error("channel %d: internal error: chan_obuf_empty for non empty buffer",
7e7327a1	201	c->self);
8efc0c15	202	return;
8efc0c15	203	}
5260325f	204	switch (c->ostate) {
8efc0c15	205	case CHAN_OUTPUT_WAIT_DRAIN:
7e7327a1	206	debug("channel %d: output drain -> closed", c->self);
7e7327a1	207	chan_send_oclose1(c);
5260325f	208	c->ostate = CHAN_OUTPUT_CLOSED;
8efc0c15	209	break;
8efc0c15	210	default:
7e7327a1	211	error("channel %d: internal error: chan_obuf_empty for ostate %d",
7e7327a1	212	c->self, c->ostate);
8efc0c15	213	break;
	214	}
	215	}
8efc0c15	216	static void
7e7327a1	217	chan_send_ieof1(Channel *c)
5260325f	218	{
7e7327a1	219	debug("channel %d: send ieof", c->self);
5260325f	220	switch (c->istate) {
8efc0c15	221	case CHAN_INPUT_OPEN:
	222	case CHAN_INPUT_WAIT_DRAIN:
	223	packet_start(SSH_MSG_CHANNEL_INPUT_EOF);
	224	packet_put_int(c->remote_id);
	225	packet_send();
	226	break;
	227	default:
7e7327a1	228	error("channel %d: internal error: cannot send ieof for istate %d",
7e7327a1	229	c->self, c->istate);
8efc0c15	230	break;
	231	}
	232	}
	233	static void
7e7327a1	234	chan_send_oclose1(Channel *c)
5260325f	235	{
7e7327a1	236	debug("channel %d: send oclose", c->self);
5260325f	237	switch (c->ostate) {
8efc0c15	238	case CHAN_OUTPUT_OPEN:
	239	case CHAN_OUTPUT_WAIT_DRAIN:
	240	chan_shutdown_write(c);
	241	buffer_consume(&c->output, buffer_len(&c->output));
	242	packet_start(SSH_MSG_CHANNEL_OUTPUT_CLOSE);
	243	packet_put_int(c->remote_id);
	244	packet_send();
	245	break;
	246	default:
7e7327a1	247	error("channel %d: internal error: cannot send oclose for ostate %d",
7e7327a1	248	c->self, c->ostate);
8efc0c15	249	break;
	250	}
	251	}
7e7327a1	252	static void
	253	chan_delete_if_full_closed1(Channel *c)
	254	{
fa08c86b	255	debug3("channel %d: chan_delete_if_full_closed1: istate %d ostate %d",
fa08c86b	256	c->self, c->istate, c->ostate);
7e7327a1	257	if (c->istate == CHAN_INPUT_CLOSED && c->ostate == CHAN_OUTPUT_CLOSED) {
	258	debug("channel %d: full closed", c->self);
	259	channel_free(c->self);
	260	}
	261	}
5260325f	262
7e7327a1	263	/*
	264	* the same for SSH2
	265	*/
8efc0c15	266	static void
7e7327a1	267	chan_rcvd_oclose2(Channel *c)
5260325f	268	{
7e7327a1	269	debug("channel %d: rcvd close", c->self);
	270	if (c->flags & CHAN_CLOSE_RCVD)
	271	error("channel %d: protocol error: close rcvd twice", c->self);
	272	c->flags \|= CHAN_CLOSE_RCVD;
	273	if (c->type == SSH_CHANNEL_LARVAL) {
	274	/* tear down larval channels immediately */
	275	c->ostate = CHAN_OUTPUT_CLOSED;
	276	c->istate = CHAN_INPUT_CLOSED;
	277	return;
	278	}
	279	switch (c->ostate) {
	280	case CHAN_OUTPUT_OPEN:
	281	/* wait until a data from the channel is consumed if a CLOSE is received */
	282	debug("channel %d: output open -> drain", c->self);
	283	c->ostate = CHAN_OUTPUT_WAIT_DRAIN;
	284	break;
	285	}
	286	switch (c->istate) {
	287	case CHAN_INPUT_OPEN:
	288	debug("channel %d: input open -> closed", c->self);
	289	chan_shutdown_read(c);
	290	break;
	291	case CHAN_INPUT_WAIT_DRAIN:
	292	debug("channel %d: input drain -> closed", c->self);
	293	chan_send_eof2(c);
	294	break;
	295	}
	296	c->istate = CHAN_INPUT_CLOSED;
8efc0c15	297	}
8efc0c15	298	static void
7e7327a1	299	chan_ibuf_empty2(Channel *c)
	300	{
	301	debug("channel %d: ibuf empty", c->self);
	302	if (buffer_len(&c->input)) {
	303	error("channel %d: internal error: chan_ibuf_empty for non empty buffer",
	304	c->self);
	305	return;
	306	}
	307	switch (c->istate) {
	308	case CHAN_INPUT_WAIT_DRAIN:
	309	debug("channel %d: input drain -> closed", c->self);
	310	if (!(c->flags & CHAN_CLOSE_SENT))
	311	chan_send_eof2(c);
	312	c->istate = CHAN_INPUT_CLOSED;
	313	break;
	314	default:
	315	error("channel %d: internal error: chan_ibuf_empty for istate %d",
	316	c->self, c->istate);
	317	break;
	318	}
	319	}
	320	static void
	321	chan_rcvd_ieof2(Channel *c)
5260325f	322	{
7e7327a1	323	debug("channel %d: rcvd eof", c->self);
	324	if (c->ostate == CHAN_OUTPUT_OPEN) {
	325	debug("channel %d: output open -> drain", c->self);
	326	c->ostate = CHAN_OUTPUT_WAIT_DRAIN;
	327	}
8efc0c15	328	}
7e7327a1	329	static void
	330	chan_write_failed2(Channel *c)
	331	{
	332	debug("channel %d: write failed", c->self);
	333	switch (c->ostate) {
	334	case CHAN_OUTPUT_OPEN:
	335	debug("channel %d: output open -> closed", c->self);
1d1ffb87	336	chan_shutdown_write(c); /* ?? */
7e7327a1	337	c->ostate = CHAN_OUTPUT_CLOSED;
	338	break;
	339	case CHAN_OUTPUT_WAIT_DRAIN:
	340	debug("channel %d: output drain -> closed", c->self);
	341	chan_shutdown_write(c);
	342	c->ostate = CHAN_OUTPUT_CLOSED;
	343	break;
	344	default:
	345	error("channel %d: internal error: chan_write_failed for ostate %d",
	346	c->self, c->ostate);
	347	break;
	348	}
	349	}
	350	static void
	351	chan_obuf_empty2(Channel *c)
	352	{
	353	debug("channel %d: obuf empty", c->self);
	354	if (buffer_len(&c->output)) {
	355	error("internal error: chan_obuf_empty %d for non empty buffer",
	356	c->self);
	357	return;
	358	}
	359	switch (c->ostate) {
	360	case CHAN_OUTPUT_WAIT_DRAIN:
	361	debug("channel %d: output drain -> closed", c->self);
	362	chan_shutdown_write(c);
	363	c->ostate = CHAN_OUTPUT_CLOSED;
	364	break;
	365	default:
	366	error("channel %d: internal error: chan_obuf_empty for ostate %d",
	367	c->self, c->ostate);
	368	break;
	369	}
	370	}
	371	static void
	372	chan_send_eof2(Channel *c)
	373	{
	374	debug("channel %d: send eof", c->self);
	375	switch (c->istate) {
	376	case CHAN_INPUT_WAIT_DRAIN:
	377	packet_start(SSH2_MSG_CHANNEL_EOF);
	378	packet_put_int(c->remote_id);
	379	packet_send();
	380	break;
	381	default:
	382	error("channel %d: internal error: cannot send eof for istate %d",
	383	c->self, c->istate);
	384	break;
	385	}
	386	}
	387	static void
	388	chan_send_close2(Channel *c)
	389	{
	390	debug("channel %d: send close", c->self);
	391	if (c->ostate != CHAN_OUTPUT_CLOSED \|\|
	392	c->istate != CHAN_INPUT_CLOSED) {
	393	error("channel %d: internal error: cannot send close for istate/ostate %d/%d",
	394	c->self, c->istate, c->ostate);
	395	} else if (c->flags & CHAN_CLOSE_SENT) {
	396	error("channel %d: internal error: already sent close", c->self);
	397	} else {
	398	packet_start(SSH2_MSG_CHANNEL_CLOSE);
	399	packet_put_int(c->remote_id);
	400	packet_send();
401	c->flags \|= CHAN_CLOSE_SENT;
402	}
403	}
404	static void
405	chan_delete_if_full_closed2(Channel *c)
5260325f	406	{
fa08c86b	407	debug3("channel %d: chan_delete_if_full_closed2: istate %d ostate %d",
fa08c86b	408	c->self, c->istate, c->ostate);
5260325f	409	if (c->istate == CHAN_INPUT_CLOSED && c->ostate == CHAN_OUTPUT_CLOSED) {
7e7327a1	410	if (!(c->flags & CHAN_CLOSE_SENT)) {
	411	chan_send_close2(c);
	412	}
6ae2364d	413	if ((c->flags & CHAN_CLOSE_SENT) &&
7e7327a1	414	(c->flags & CHAN_CLOSE_RCVD)) {
	415	debug("channel %d: full closed2", c->self);
	416	channel_free(c->self);
6ae2364d	417	}
8efc0c15	418	}
8efc0c15	419	}
7e7327a1	420
7e7327a1	421	/* shared */
8efc0c15	422	void
5260325f	423	chan_init_iostates(Channel *c)
	424	{
	425	c->ostate = CHAN_OUTPUT_OPEN;
	426	c->istate = CHAN_INPUT_OPEN;
7e7327a1	427	c->flags = 0;
	428	}
	429
	430	/* init */
	431	void
	432	chan_init(void)
	433	{
	434	if (compat20) {
	435	chan_rcvd_oclose = chan_rcvd_oclose2;
	436	chan_read_failed = chan_read_failed_12;
	437	chan_ibuf_empty = chan_ibuf_empty2;
	438
	439	chan_rcvd_ieof = chan_rcvd_ieof2;
	440	chan_write_failed = chan_write_failed2;
	441	chan_obuf_empty = chan_obuf_empty2;
	442
	443	chan_delete_if_full_closed = chan_delete_if_full_closed2;
	444	} else {
	445	chan_rcvd_oclose = chan_rcvd_oclose1;
	446	chan_read_failed = chan_read_failed_12;
	447	chan_ibuf_empty = chan_ibuf_empty1;
	448
	449	chan_rcvd_ieof = chan_rcvd_ieof1;
	450	chan_write_failed = chan_write_failed1;
	451	chan_obuf_empty = chan_obuf_empty1;
	452
	453	chan_delete_if_full_closed = chan_delete_if_full_closed1;
	454	}
	455	}
	456
	457	/* helper */
	458	static void
	459	chan_shutdown_write(Channel *c)
	460	{
	461	buffer_consume(&c->output, buffer_len(&c->output));
	462	if (compat20 && c->type == SSH_CHANNEL_LARVAL)
	463	return;
	464	/* shutdown failure is allowed if write failed already */
	465	debug("channel %d: close_write", c->self);
	466	if (c->sock != -1) {
	467	if (shutdown(c->sock, SHUT_WR) < 0)
	468	debug("channel %d: chan_shutdown_write: shutdown() failed for fd%d: %.100s",
	469	c->self, c->sock, strerror(errno));
	470	} else {
	471	if (close(c->wfd) < 0)
	472	log("channel %d: chan_shutdown_write: close() failed for fd%d: %.100s",
	473	c->self, c->wfd, strerror(errno));
	474	c->wfd = -1;
	475	}
	476	}
	477	static void
	478	chan_shutdown_read(Channel *c)
	479	{
	480	if (compat20 && c->type == SSH_CHANNEL_LARVAL)
	481	return;
	482	debug("channel %d: close_read", c->self);
	483	if (c->sock != -1) {
47670e77	484	/*
	485	* shutdown(sock, SHUT_READ) may return ENOTCONN if the
	486	* write side has been closed already. (bug on Linux)
	487	*/
	488	if (shutdown(c->sock, SHUT_RD) < 0
	489	&& (errno != ENOTCONN
	490	\|\| c->ostate == CHAN_OUTPUT_OPEN
	491	\|\| c->ostate == CHAN_OUTPUT_WAIT_DRAIN))
7e7327a1	492	error("channel %d: chan_shutdown_read: shutdown() failed for fd%d [i%d o%d]: %.100s",
	493	c->self, c->sock, c->istate, c->ostate, strerror(errno));
	494	} else {
	495	if (close(c->rfd) < 0)
	496	log("channel %d: chan_shutdown_read: close() failed for fd%d: %.100s",
	497	c->self, c->rfd, strerror(errno));
	498	c->rfd = -1;
	499	}
8efc0c15	500	}