/* Copyright (c) 2004-2007 Sara Golemon <sarag@libssh2.org>

* Copyright (c) 2005 Mikhail Gusarov <dottedmag@dottedmag.net>

* Copyright (c) 2008-2019 by Daniel Stenberg

*

* All rights reserved.

*

* Redistribution and use in source and binary forms,

* with or without modification, are permitted provided

* that the following conditions are met:

*

* Redistributions of source code must retain the above

* copyright notice, this list of conditions and the

* following disclaimer.

*

* 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.

*

* Neither the name of the copyright holder nor the names

* of any other contributors may be used to endorse or

* promote products derived from this software without

* specific prior written permission.

*

* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND

* CONTRIBUTORS "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 COPYRIGHT OWNER OR

* CONTRIBUTORS 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 "libssh2_priv.h"

#ifdef HAVE_UNISTD_H

#include <unistd.h>

#endif

#include <fcntl.h>

#ifdef HAVE_INTTYPES_H

#include <inttypes.h>

#endif

#include <assert.h>

#include "channel.h"

#include "transport.h"

#include "packet.h"

#include "session.h"

/*

* _libssh2_channel_nextid

*

* Determine the next channel ID we can use at our end

*/

uint32_t

_libssh2_channel_nextid(LIBSSH2_SESSION * session)

{

uint32_t id = session->next_channel;

LIBSSH2_CHANNEL *channel;

channel = _libssh2_list_first(&session->channels);

while(channel) {

if(channel->local.id > id) {

id = channel->local.id;

}

channel = _libssh2_list_next(&channel->node);

}

/* This is a shortcut to avoid waiting for close packets on channels we've

* forgotten about, This *could* be a problem if we request and close 4

* billion or so channels in too rapid succession for the remote end to

* respond, but the worst case scenario is that some data meant for

* another channel Gets picked up by the new one.... Pretty unlikely all

* told...

*/

session->next_channel = id + 1;

_libssh2_debug(session, LIBSSH2_TRACE_CONN, "Allocated new channel ID#%lu",

id);

return id;

}

/*

* _libssh2_channel_locate

*

* Locate a channel pointer by number

*/

LIBSSH2_CHANNEL *

_libssh2_channel_locate(LIBSSH2_SESSION *session, uint32_t channel_id)

{

LIBSSH2_CHANNEL *channel;

LIBSSH2_LISTENER *l;

for(channel = _libssh2_list_first(&session->channels);

channel;

channel = _libssh2_list_next(&channel->node)) {

if(channel->local.id == channel_id)

return channel;

}

/* We didn't find the channel in the session, let's then check its

listeners since each listener may have its own set of pending channels

*/

for(l = _libssh2_list_first(&session->listeners); l;

l = _libssh2_list_next(&l->node)) {

for(channel = _libssh2_list_first(&l->queue);

channel;

channel = _libssh2_list_next(&channel->node)) {

if(channel->local.id == channel_id)

return channel;

}

}

return NULL;

}

/*

* _libssh2_channel_open

*

* Establish a generic session channel

*/

LIBSSH2_CHANNEL *

_libssh2_channel_open(LIBSSH2_SESSION * session, const char *channel_type,

uint32_t channel_type_len,

uint32_t window_size,

uint32_t packet_size,

const unsigned char *message,

size_t message_len)

{

static const unsigned char reply_codes[3] = {

SSH_MSG_CHANNEL_OPEN_CONFIRMATION,

SSH_MSG_CHANNEL_OPEN_FAILURE,

0

};

unsigned char *s;

int rc;

if(session->open_state == libssh2_NB_state_idle) {

session->open_channel = NULL;

session->open_packet = NULL;

session->open_data = NULL;

/* 17 = packet_type(1) + channel_type_len(4) + sender_channel(4) +

* window_size(4) + packet_size(4) */

session->open_packet_len = channel_type_len + 17;

session->open_local_channel = _libssh2_channel_nextid(session);

/* Zero the whole thing out */

memset(&session->open_packet_requirev_state, 0,

sizeof(session->open_packet_requirev_state));

_libssh2_debug(session, LIBSSH2_TRACE_CONN,

"Opening Channel - win %d pack %d", window_size,

packet_size);

session->open_channel =

LIBSSH2_CALLOC(session, sizeof(LIBSSH2_CHANNEL));

if(!session->open_channel) {

_libssh2_error(session, LIBSSH2_ERROR_ALLOC,

"Unable to allocate space for channel data");

return NULL;

}

session->open_channel->channel_type_len = channel_type_len;

session->open_channel->channel_type =

LIBSSH2_ALLOC(session, channel_type_len);

if(!session->open_channel->channel_type) {

_libssh2_error(session, LIBSSH2_ERROR_ALLOC,

"Failed allocating memory for channel type name");

LIBSSH2_FREE(session, session->open_channel);

session->open_channel = NULL;

return NULL;

}

memcpy(session->open_channel->channel_type, channel_type,

channel_type_len);

/* REMEMBER: local as in locally sourced */

session->open_channel->local.id = session->open_local_channel;

session->open_channel->remote.window_size = window_size;

session->open_channel->remote.window_size_initial = window_size;

session->open_channel->remote.packet_size = packet_size;

session->open_channel->session = session;

_libssh2_list_add(&session->channels,

&session->open_channel->node);

s = session->open_packet =

LIBSSH2_ALLOC(session, session->open_packet_len);

if(!session->open_packet) {

_libssh2_error(session, LIBSSH2_ERROR_ALLOC,

"Unable to allocate temporary space for packet");

goto channel_error;

}

*(s++) = SSH_MSG_CHANNEL_OPEN;

_libssh2_store_str(&s, channel_type, channel_type_len);

_libssh2_store_u32(&s, session->open_local_channel);

_libssh2_store_u32(&s, window_size);

_libssh2_store_u32(&s, packet_size);

/* Do not copy the message */

session->open_state = libssh2_NB_state_created;

}

if(session->open_state == libssh2_NB_state_created) {

rc = _libssh2_transport_send(session,

session->open_packet,

session->open_packet_len,

message, message_len);

if(rc == LIBSSH2_ERROR_EAGAIN) {

_libssh2_error(session, rc,

"Would block sending channel-open request");

return NULL;

}

else if(rc) {

_libssh2_error(session, rc,

"Unable to send channel-open request");

goto channel_error;

}

session->open_state = libssh2_NB_state_sent;

}

if(session->open_state == libssh2_NB_state_sent) {

rc = _libssh2_packet_requirev(session, reply_codes,

&session->open_data,

&session->open_data_len, 1,

session->open_packet + 5 +

channel_type_len, 4,

&session->open_packet_requirev_state);

if(rc == LIBSSH2_ERROR_EAGAIN) {

_libssh2_error(session, LIBSSH2_ERROR_EAGAIN, "Would block");

return NULL;

}

else if(rc) {

goto channel_error;

}

if(session->open_data_len < 1) {

_libssh2_error(session, LIBSSH2_ERROR_PROTO,

"Unexpected packet size");

goto channel_error;

}

if(session->open_data[0] == SSH_MSG_CHANNEL_OPEN_CONFIRMATION) {

if(session->open_data_len < 17) {

_libssh2_error(session, LIBSSH2_ERROR_PROTO,

"Unexpected packet size");

goto channel_error;

}

session->open_channel->remote.id =

_libssh2_ntohu32(session->open_data + 5);

session->open_channel->local.window_size =

_libssh2_ntohu32(session->open_data + 9);

session->open_channel->local.window_size_initial =

_libssh2_ntohu32(session->open_data + 9);

session->open_channel->local.packet_size =

_libssh2_ntohu32(session->open_data + 13);

_libssh2_debug(session, LIBSSH2_TRACE_CONN,

"Connection Established - ID: %lu/%lu win: %lu/%lu"

" pack: %lu/%lu",

session->open_channel->local.id,

session->open_channel->remote.id,

session->open_channel->local.window_size,

session->open_channel->remote.window_size,

session->open_channel->local.packet_size,

session->open_channel->remote.packet_size);

LIBSSH2_FREE(session, session->open_packet);

session->open_packet = NULL;

LIBSSH2_FREE(session, session->open_data);

session->open_data = NULL;

session->open_state = libssh2_NB_state_idle;

return session->open_channel;

}

if(session->open_data[0] == SSH_MSG_CHANNEL_OPEN_FAILURE) {

unsigned int reason_code =

_libssh2_ntohu32(session->open_data + 5);

switch(reason_code) {

case SSH_OPEN_ADMINISTRATIVELY_PROHIBITED:

_libssh2_error(session, LIBSSH2_ERROR_CHANNEL_FAILURE,

"Channel open failure "

"(administratively prohibited)");

break;

case SSH_OPEN_CONNECT_FAILED:

_libssh2_error(session, LIBSSH2_ERROR_CHANNEL_FAILURE,

"Channel open failure (connect failed)");

break;

case SSH_OPEN_UNKNOWN_CHANNELTYPE:

_libssh2_error(session, LIBSSH2_ERROR_CHANNEL_FAILURE,

"Channel open failure (unknown channel type)");

break;

case SSH_OPEN_RESOURCE_SHORTAGE:

_libssh2_error(session, LIBSSH2_ERROR_CHANNEL_FAILURE,

"Channel open failure (resource shortage)");

break;

default:

_libssh2_error(session, LIBSSH2_ERROR_CHANNEL_FAILURE,

"Channel open failure");

}

}

}

channel_error:

if(session->open_data) {

LIBSSH2_FREE(session, session->open_data);

session->open_data = NULL;

}

if(session->open_packet) {

LIBSSH2_FREE(session, session->open_packet);

session->open_packet = NULL;

}

if(session->open_channel) {

unsigned char channel_id[4];

LIBSSH2_FREE(session, session->open_channel->channel_type);

_libssh2_list_remove(&session->open_channel->node);

/* Clear out packets meant for this channel */

_libssh2_htonu32(channel_id, session->open_channel->local.id);

while((_libssh2_packet_ask(session, SSH_MSG_CHANNEL_DATA,

&session->open_data,

&session->open_data_len, 1,

channel_id, 4) >= 0)

||

(_libssh2_packet_ask(session, SSH_MSG_CHANNEL_EXTENDED_DATA,

&session->open_data,

&session->open_data_len, 1,

channel_id, 4) >= 0)) {

LIBSSH2_FREE(session, session->open_data);

session->open_data = NULL;

}

LIBSSH2_FREE(session, session->open_channel);

session->open_channel = NULL;

}

session->open_state = libssh2_NB_state_idle;

return NULL;

}

/*

* libssh2_channel_open_ex

*

* Establish a generic session channel

*/

LIBSSH2_API LIBSSH2_CHANNEL *

libssh2_channel_open_ex(LIBSSH2_SESSION *session, const char *type,

unsigned int type_len,

unsigned int window_size, unsigned int packet_size,

const char *msg, unsigned int msg_len)

{

LIBSSH2_CHANNEL *ptr;

if(!session)

return NULL;

BLOCK_ADJUST_ERRNO(ptr, session,

_libssh2_channel_open(session, type, type_len,

window_size, packet_size,

(unsigned char *)msg,

msg_len));

return ptr;

}

/*

* libssh2_channel_direct_tcpip_ex

*

* Tunnel TCP/IP connect through the SSH session to direct host/port

*/

static LIBSSH2_CHANNEL *

channel_direct_tcpip(LIBSSH2_SESSION * session, const char *host,

int port, const char *shost, int sport)

{

LIBSSH2_CHANNEL *channel;

unsigned char *s;

if(session->direct_state == libssh2_NB_state_idle) {

session->direct_host_len = strlen(host);

session->direct_shost_len = strlen(shost);

/* host_len(4) + port(4) + shost_len(4) + sport(4) */

session->direct_message_len =

session->direct_host_len + session->direct_shost_len + 16;

_libssh2_debug(session, LIBSSH2_TRACE_CONN,

"Requesting direct-tcpip session from %s:%d to %s:%d",

shost, sport, host, port);

s = session->direct_message =

LIBSSH2_ALLOC(session, session->direct_message_len);

if(!session->direct_message) {

_libssh2_error(session, LIBSSH2_ERROR_ALLOC,

"Unable to allocate memory for "

"direct-tcpip connection");

return NULL;

}

_libssh2_store_str(&s, host, session->direct_host_len);

_libssh2_store_u32(&s, port);

_libssh2_store_str(&s, shost, session->direct_shost_len);

_libssh2_store_u32(&s, sport);

}

channel =

_libssh2_channel_open(session, "direct-tcpip",

sizeof("direct-tcpip") - 1,

LIBSSH2_CHANNEL_WINDOW_DEFAULT,

LIBSSH2_CHANNEL_PACKET_DEFAULT,

session->direct_message,

session->direct_message_len);

if(!channel &&

libssh2_session_last_errno(session) == LIBSSH2_ERROR_EAGAIN) {

/* The error code is still set to LIBSSH2_ERROR_EAGAIN, set our state

to created to avoid re-creating the package on next invoke */

session->direct_state = libssh2_NB_state_created;

return NULL;

}

/* by default we set (keep?) idle state... */

session->direct_state = libssh2_NB_state_idle;

LIBSSH2_FREE(session, session->direct_message);

session->direct_message = NULL;

return channel;

}

/*

* libssh2_channel_direct_tcpip_ex

*

* Tunnel TCP/IP connect through the SSH session to direct host/port

*/

LIBSSH2_API LIBSSH2_CHANNEL *

libssh2_channel_direct_tcpip_ex(LIBSSH2_SESSION *session, const char *host,

int port, const char *shost, int sport)

{

LIBSSH2_CHANNEL *ptr;

if(!session)

return NULL;

BLOCK_ADJUST_ERRNO(ptr, session,

channel_direct_tcpip(session, host, port,

shost, sport));

return ptr;

}

/*

* channel_forward_listen

*

* Bind a port on the remote host and listen for connections

*/

static LIBSSH2_LISTENER *

channel_forward_listen(LIBSSH2_SESSION * session, const char *host,

int port, int *bound_port, int queue_maxsize)

{

unsigned char *s;

static const unsigned char reply_codes[3] =

{ SSH_MSG_REQUEST_SUCCESS, SSH_MSG_REQUEST_FAILURE, 0 };

int rc;

if(!host)

host = "0.0.0.0";

if(session->fwdLstn_state == libssh2_NB_state_idle) {

session->fwdLstn_host_len = strlen(host);

/* 14 = packet_type(1) + request_len(4) + want_replay(1) + host_len(4)

+ port(4) */

session->fwdLstn_packet_len =

session->fwdLstn_host_len + (sizeof("tcpip-forward") - 1) + 14;

/* Zero the whole thing out */

memset(&session->fwdLstn_packet_requirev_state, 0,

sizeof(session->fwdLstn_packet_requirev_state));

_libssh2_debug(session, LIBSSH2_TRACE_CONN,

"Requesting tcpip-forward session for %s:%d", host,

port);

s = session->fwdLstn_packet =

LIBSSH2_ALLOC(session, session->fwdLstn_packet_len);

if(!session->fwdLstn_packet) {

_libssh2_error(session, LIBSSH2_ERROR_ALLOC,

"Unable to allocate memory for setenv packet");

return NULL;

}

*(s++) = SSH_MSG_GLOBAL_REQUEST;

_libssh2_store_str(&s, "tcpip-forward", sizeof("tcpip-forward") - 1);

*(s++) = 0x01; /* want_reply */

_libssh2_store_str(&s, host, session->fwdLstn_host_len);

_libssh2_store_u32(&s, port);

session->fwdLstn_state = libssh2_NB_state_created;

}

if(session->fwdLstn_state == libssh2_NB_state_created) {

rc = _libssh2_transport_send(session,

session->fwdLstn_packet,

session->fwdLstn_packet_len,

NULL, 0);

if(rc == LIBSSH2_ERROR_EAGAIN) {

_libssh2_error(session, LIBSSH2_ERROR_EAGAIN,

"Would block sending global-request packet for "

"forward listen request");

return NULL;

}

else if(rc) {

_libssh2_error(session, LIBSSH2_ERROR_SOCKET_SEND,

"Unable to send global-request packet for forward "

"listen request");

LIBSSH2_FREE(session, session->fwdLstn_packet);

session->fwdLstn_packet = NULL;

session->fwdLstn_state = libssh2_NB_state_idle;

return NULL;

}

LIBSSH2_FREE(session, session->fwdLstn_packet);

session->fwdLstn_packet = NULL;

session->fwdLstn_state = libssh2_NB_state_sent;

}

if(session->fwdLstn_state == libssh2_NB_state_sent) {

unsigned char *data;

size_t data_len;

rc = _libssh2_packet_requirev(session, reply_codes, &data, &data_len,

0, NULL, 0,

&session->fwdLstn_packet_requirev_state);

if(rc == LIBSSH2_ERROR_EAGAIN) {

_libssh2_error(session, LIBSSH2_ERROR_EAGAIN, "Would block");

return NULL;

}

else if(rc || (data_len < 1)) {

_libssh2_error(session, LIBSSH2_ERROR_PROTO, "Unknown");

session->fwdLstn_state = libssh2_NB_state_idle;

return NULL;

}

if(data[0] == SSH_MSG_REQUEST_SUCCESS) {

LIBSSH2_LISTENER *listener;

listener = LIBSSH2_CALLOC(session, sizeof(LIBSSH2_LISTENER));

if(!listener)

_libssh2_error(session, LIBSSH2_ERROR_ALLOC,

"Unable to allocate memory for listener queue");

else {

listener->host =

LIBSSH2_ALLOC(session, session->fwdLstn_host_len + 1);

if(!listener->host) {

_libssh2_error(session, LIBSSH2_ERROR_ALLOC,

"Unable to allocate memory "

"for listener queue");

LIBSSH2_FREE(session, listener);

listener = NULL;

}

else {

listener->session = session;

memcpy(listener->host, host, session->fwdLstn_host_len);

listener->host[session->fwdLstn_host_len] = 0;

if(data_len >= 5 && !port) {

listener->port = _libssh2_ntohu32(data + 1);

_libssh2_debug(session, LIBSSH2_TRACE_CONN,

"Dynamic tcpip-forward port "

"allocated: %d",

listener->port);

}

else

listener->port = port;

listener->queue_size = 0;

listener->queue_maxsize = queue_maxsize;

/* append this to the parent's list of listeners */

_libssh2_list_add(&session->listeners, &listener->node);

if(bound_port) {

*bound_port = listener->port;

}

}

}

LIBSSH2_FREE(session, data);

session->fwdLstn_state = libssh2_NB_state_idle;

return listener;

}

else if(data[0] == SSH_MSG_REQUEST_FAILURE) {

LIBSSH2_FREE(session, data);

_libssh2_error(session, LIBSSH2_ERROR_REQUEST_DENIED,

"Unable to complete request for forward-listen");

session->fwdLstn_state = libssh2_NB_state_idle;

return NULL;

}

}

session->fwdLstn_state = libssh2_NB_state_idle;

return NULL;

}

/*

* libssh2_channel_forward_listen_ex

*

* Bind a port on the remote host and listen for connections

*/

LIBSSH2_API LIBSSH2_LISTENER *

libssh2_channel_forward_listen_ex(LIBSSH2_SESSION *session, const char *host,

int port, int *bound_port, int queue_maxsize)

{

LIBSSH2_LISTENER *ptr;

if(!session)

return NULL;

BLOCK_ADJUST_ERRNO(ptr, session,

channel_forward_listen(session, host, port, bound_port,

queue_maxsize));

return ptr;

}

/*

* _libssh2_channel_forward_cancel

*

* Stop listening on a remote port and free the listener

* Toss out any pending (un-accept()ed) connections

*

* Return 0 on success, LIBSSH2_ERROR_EAGAIN if would block, -1 on error

*/

int _libssh2_channel_forward_cancel(LIBSSH2_LISTENER *listener)

{

LIBSSH2_SESSION *session = listener->session;

LIBSSH2_CHANNEL *queued;

unsigned char *packet, *s;

size_t host_len = strlen(listener->host);

/* 14 = packet_type(1) + request_len(4) + want_replay(1) + host_len(4) +

port(4) */

size_t packet_len =

host_len + 14 + sizeof("cancel-tcpip-forward") - 1;

int rc;

int retcode = 0;

if(listener->chanFwdCncl_state == libssh2_NB_state_idle) {

_libssh2_debug(session, LIBSSH2_TRACE_CONN,

"Cancelling tcpip-forward session for %s:%d",

listener->host, listener->port);

s = packet = LIBSSH2_ALLOC(session, packet_len);

if(!packet) {

_libssh2_error(session, LIBSSH2_ERROR_ALLOC,

"Unable to allocate memory for setenv packet");

return LIBSSH2_ERROR_ALLOC;

}

*(s++) = SSH_MSG_GLOBAL_REQUEST;

_libssh2_store_str(&s, "cancel-tcpip-forward",

sizeof("cancel-tcpip-forward") - 1);

*(s++) = 0x00; /* want_reply */

_libssh2_store_str(&s, listener->host, host_len);

_libssh2_store_u32(&s, listener->port);

listener->chanFwdCncl_state = libssh2_NB_state_created;

}

else {

packet = listener->chanFwdCncl_data;

}

if(listener->chanFwdCncl_state == libssh2_NB_state_created) {

rc = _libssh2_transport_send(session, packet, packet_len, NULL, 0);

if(rc == LIBSSH2_ERROR_EAGAIN) {

_libssh2_error(session, rc,

"Would block sending forward request");

listener->chanFwdCncl_data = packet;

return rc;

}

else if(rc) {

_libssh2_error(session, LIBSSH2_ERROR_SOCKET_SEND,

"Unable to send global-request packet for forward "

"listen request");

/* set the state to something we don't check for, for the

unfortunate situation where we get an EAGAIN further down

when trying to bail out due to errors! */

listener->chanFwdCncl_state = libssh2_NB_state_sent;

retcode = LIBSSH2_ERROR_SOCKET_SEND;

}

LIBSSH2_FREE(session, packet);

listener->chanFwdCncl_state = libssh2_NB_state_sent;

}

queued = _libssh2_list_first(&listener->queue);

while(queued) {

LIBSSH2_CHANNEL *next = _libssh2_list_next(&queued->node);

rc = _libssh2_channel_free(queued);

if(rc == LIBSSH2_ERROR_EAGAIN) {

return rc;

}

queued = next;

}

LIBSSH2_FREE(session, listener->host);

/* remove this entry from the parent's list of listeners */

_libssh2_list_remove(&listener->node);

LIBSSH2_FREE(session, listener);

return retcode;

}

/*

* libssh2_channel_forward_cancel

*

* Stop listening on a remote port and free the listener

* Toss out any pending (un-accept()ed) connections

*

* Return 0 on success, LIBSSH2_ERROR_EAGAIN if would block, -1 on error

*/

LIBSSH2_API int

libssh2_channel_forward_cancel(LIBSSH2_LISTENER *listener)

{

int rc;

if(!listener)

return LIBSSH2_ERROR_BAD_USE;

BLOCK_ADJUST(rc, listener->session,

_libssh2_channel_forward_cancel(listener));

return rc;

}

/*

* channel_forward_accept

*

* Accept a connection

*/

static LIBSSH2_CHANNEL *

channel_forward_accept(LIBSSH2_LISTENER *listener)

{

int rc;

do {

rc = _libssh2_transport_read(listener->session);

} while(rc > 0);

if(_libssh2_list_first(&listener->queue)) {

LIBSSH2_CHANNEL *channel = _libssh2_list_first(&listener->queue);

/* detach channel from listener's queue */

_libssh2_list_remove(&channel->node);

listener->queue_size--;

/* add channel to session's channel list */

_libssh2_list_add(&channel->session->channels, &channel->node);

return channel;

}

if(rc == LIBSSH2_ERROR_EAGAIN) {

_libssh2_error(listener->session, LIBSSH2_ERROR_EAGAIN,

"Would block waiting for packet");

}

else

_libssh2_error(listener->session, LIBSSH2_ERROR_CHANNEL_UNKNOWN,

"Channel not found");

return NULL;

}

/*

* libssh2_channel_forward_accept

*

* Accept a connection

*/

LIBSSH2_API LIBSSH2_CHANNEL *

libssh2_channel_forward_accept(LIBSSH2_LISTENER *listener)

{

LIBSSH2_CHANNEL *ptr;

if(!listener)

return NULL;

BLOCK_ADJUST_ERRNO(ptr, listener->session,

channel_forward_accept(listener));

return ptr;

}

/*

* channel_setenv

*

* Set an environment variable prior to requesting a shell/program/subsystem

*/

static int channel_setenv(LIBSSH2_CHANNEL *channel,

const char *varname, unsigned int varname_len,

const char *value, unsigned int value_len)

{

LIBSSH2_SESSION *session = channel->session;

unsigned char *s, *data;

static const unsigned char reply_codes[3] =

{ SSH_MSG_CHANNEL_SUCCESS, SSH_MSG_CHANNEL_FAILURE, 0 };

size_t data_len;

int rc;

if(channel->setenv_state == libssh2_NB_state_idle) {

/* 21 = packet_type(1) + channel_id(4) + request_len(4) +

* request(3)"env" + want_reply(1) + varname_len(4) + value_len(4) */

channel->setenv_packet_len = varname_len + value_len + 21;

/* Zero the whole thing out */

memset(&channel->setenv_packet_requirev_state, 0,

sizeof(channel->setenv_packet_requirev_state));

_libssh2_debug(session, LIBSSH2_TRACE_CONN,

"Setting remote environment variable: %s=%s on "

"channel %lu/%lu",

varname, value, channel->local.id, channel->remote.id);

s = channel->setenv_packet =

LIBSSH2_ALLOC(session, channel->setenv_packet_len);

if(!channel->setenv_packet) {

return _libssh2_error(session, LIBSSH2_ERROR_ALLOC,

"Unable to allocate memory "

"for setenv packet");

}

*(s++) = SSH_MSG_CHANNEL_REQUEST;

_libssh2_store_u32(&s, channel->remote.id);

_libssh2_store_str(&s, "env", sizeof("env") - 1);

*(s++) = 0x01;

_libssh2_store_str(&s, varname, varname_len);

_libssh2_store_str(&s, value, value_len);

channel->setenv_state = libssh2_NB_state_created;

}

if(channel->setenv_state == libssh2_NB_state_created) {

rc = _libssh2_transport_send(session,

channel->setenv_packet,

channel->setenv_packet_len,

NULL, 0);

if(rc == LIBSSH2_ERROR_EAGAIN) {

_libssh2_error(session, rc,

"Would block sending setenv request");

return rc;

}

else if(rc) {

LIBSSH2_FREE(session, channel->setenv_packet);

channel->setenv_packet = NULL;

channel->setenv_state = libssh2_NB_state_idle;

return _libssh2_error(session, LIBSSH2_ERROR_SOCKET_SEND,

"Unable to send channel-request packet for "

"setenv request");

}

LIBSSH2_FREE(session, channel->setenv_packet);

channel->setenv_packet = NULL;

_libssh2_htonu32(channel->setenv_local_channel, channel->local.id);

channel->setenv_state = libssh2_NB_state_sent;

}

if(channel->setenv_state == libssh2_NB_state_sent) {

rc = _libssh2_packet_requirev(session, reply_codes, &data, &data_len,

1, channel->setenv_local_channel, 4,

&channel->

setenv_packet_requirev_state);

if(rc == LIBSSH2_ERROR_EAGAIN) {

return rc;

}

if(rc) {

channel->setenv_state = libssh2_NB_state_idle;

return rc;

}

else if(data_len < 1) {

channel->setenv_state = libssh2_NB_state_idle;

return _libssh2_error(session, LIBSSH2_ERROR_PROTO,

"Unexpected packet size");

}

if(data[0] == SSH_MSG_CHANNEL_SUCCESS) {

LIBSSH2_FREE(session, data);

channel->setenv_state = libssh2_NB_state_idle;

return 0;

}

LIBSSH2_FREE(session, data);

}

channel->setenv_state = libssh2_NB_state_idle;

return _libssh2_error(session, LIBSSH2_ERROR_CHANNEL_REQUEST_DENIED,

"Unable to complete request for channel-setenv");

}

/*

* libssh2_channel_setenv_ex

*

* Set an environment variable prior to requesting a shell/program/subsystem

*/

LIBSSH2_API int

libssh2_channel_setenv_ex(LIBSSH2_CHANNEL *channel,

const char *varname, unsigned int varname_len,

const char *value, unsigned int value_len)

{

int rc;

if(!channel)

return LIBSSH2_ERROR_BAD_USE;

BLOCK_ADJUST(rc, channel->session,

channel_setenv(channel, varname, varname_len,

value, value_len));

return rc;

}

/*

* channel_request_pty

* Duh... Request a PTY

*/

static int channel_request_pty(LIBSSH2_CHANNEL *channel,

const char *term, unsigned int term_len,

const char *modes, unsigned int modes_len,

int width, int height,

int width_px, int height_px)

{

LIBSSH2_SESSION *session = channel->session;

unsigned char *s;

static const unsigned char reply_codes[3] =

{ SSH_MSG_CHANNEL_SUCCESS, SSH_MSG_CHANNEL_FAILURE, 0 };

int rc;

if(channel->reqPTY_state == libssh2_NB_state_idle) {

/* 41 = packet_type(1) + channel(4) + pty_req_len(4) + "pty_req"(7) +

* want_reply(1) + term_len(4) + width(4) + height(4) + width_px(4) +

* height_px(4) + modes_len(4) */

if(term_len + modes_len > 256) {

return _libssh2_error(session, LIBSSH2_ERROR_INVAL,

"term + mode lengths too large");

}

channel->reqPTY_packet_len = term_len + modes_len + 41;

/* Zero the whole thing out */

memset(&channel->reqPTY_packet_requirev_state, 0,

sizeof(channel->reqPTY_packet_requirev_state));

_libssh2_debug(session, LIBSSH2_TRACE_CONN,

"Allocating tty on channel %lu/%lu", channel->local.id,

channel->remote.id);

s = channel->reqPTY_packet;

*(s++) = SSH_MSG_CHANNEL_REQUEST;

_libssh2_store_u32(&s, channel->remote.id);

_libssh2_store_str(&s, (char *)"pty-req", sizeof("pty-req") - 1);

*(s++) = 0x01;

_libssh2_store_str(&s, term, term_len);

_libssh2_store_u32(&s, width);

_libssh2_store_u32(&s, height);

_libssh2_store_u32(&s, width_px);

_libssh2_store_u32(&s, height_px);

_libssh2_store_str(&s, modes, modes_len);

channel->reqPTY_state = libssh2_NB_state_created;

}

if(channel->reqPTY_state == libssh2_NB_state_created) {

rc = _libssh2_transport_send(session, channel->reqPTY_packet,

channel->reqPTY_packet_len,

NULL, 0);

if(rc == LIBSSH2_ERROR_EAGAIN) {

_libssh2_error(session, rc,

"Would block sending pty request");

return rc;

}

else if(rc) {

channel->reqPTY_state = libssh2_NB_state_idle;

return _libssh2_error(session, rc,

"Unable to send pty-request packet");

}

_libssh2_htonu32(channel->reqPTY_local_channel, channel->local.id);

channel->reqPTY_state = libssh2_NB_state_sent;

}

if(channel->reqPTY_state == libssh2_NB_state_sent) {

unsigned char *data;

size_t data_len;

unsigned char code;

rc = _libssh2_packet_requirev(session, reply_codes, &data, &data_len,

1, channel->reqPTY_local_channel, 4,

&channel->reqPTY_packet_requirev_state);