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#include "includes.h"
RCSID("$Id: nchan.c,v 1.5 1999/10/25 21:04:28 markus Exp $");
#include "ssh.h"
#include "buffer.h"
#include "packet.h"
#include "channels.h"
#include "nchan.h"
static void chan_send_ieof(Channel *c);
static void chan_send_oclose(Channel *c);
static void chan_shutdown_write(Channel *c);
static void chan_shutdown_read(Channel *c);
static void chan_delele_if_full_closed(Channel *c);
/*
* EVENTS: update channel input/output states
* execute ACTIONS
*/
/* events concerning the INPUT from socket for channel (istate) */
void
chan_rcvd_oclose(Channel *c){
switch(c->istate){
case CHAN_INPUT_WAIT_OCLOSE:
debug("channel %d: INPUT_WAIT_OCLOSE -> INPUT_CLOSED [rcvd OCLOSE]", c->self);
c->istate=CHAN_INPUT_CLOSED;
chan_delele_if_full_closed(c);
break;
case CHAN_INPUT_OPEN:
debug("channel %d: INPUT_OPEN -> INPUT_CLOSED [rvcd OCLOSE, send IEOF]", c->self);
chan_shutdown_read(c);
chan_send_ieof(c);
c->istate=CHAN_INPUT_CLOSED;
chan_delele_if_full_closed(c);
break;
default:
debug("protocol error: chan_rcvd_oclose %d for istate %d",c->self,c->istate);
break;
}
}
void
chan_read_failed(Channel *c){
switch(c->istate){
case CHAN_INPUT_OPEN:
debug("channel %d: INPUT_OPEN -> INPUT_WAIT_DRAIN [read failed]", c->self);
chan_shutdown_read(c);
c->istate=CHAN_INPUT_WAIT_DRAIN;
break;
default:
debug("internal error: we do not read, but chan_read_failed %d for istate %d",
c->self,c->istate);
break;
}
}
void
chan_ibuf_empty(Channel *c){
if(buffer_len(&c->input)){
debug("internal error: chan_ibuf_empty %d for non empty buffer",c->self);
return;
}
switch(c->istate){
case CHAN_INPUT_WAIT_DRAIN:
debug("channel %d: INPUT_WAIT_DRAIN -> INPUT_WAIT_OCLOSE [inbuf empty, send IEOF]", c->self);
chan_send_ieof(c);
c->istate=CHAN_INPUT_WAIT_OCLOSE;
break;
default:
debug("internal error: chan_ibuf_empty %d for istate %d",c->self,c->istate);
break;
}
}
/* events concerning the OUTPUT from channel for socket (ostate) */
void
chan_rcvd_ieof(Channel *c){
switch(c->ostate){
case CHAN_OUTPUT_OPEN:
debug("channel %d: OUTPUT_OPEN -> OUTPUT_WAIT_DRAIN [rvcd IEOF]", c->self);
c->ostate=CHAN_OUTPUT_WAIT_DRAIN;
break;
case CHAN_OUTPUT_WAIT_IEOF:
debug("channel %d: OUTPUT_WAIT_IEOF -> OUTPUT_CLOSED [rvcd IEOF]", c->self);
c->ostate=CHAN_OUTPUT_CLOSED;
chan_delele_if_full_closed(c);
break;
default:
debug("protocol error: chan_rcvd_ieof %d for ostate %d", c->self,c->ostate);
break;
}
}
void
chan_write_failed(Channel *c){
switch(c->ostate){
case CHAN_OUTPUT_OPEN:
debug("channel %d: OUTPUT_OPEN -> OUTPUT_WAIT_IEOF [write failed]", c->self);
chan_send_oclose(c);
c->ostate=CHAN_OUTPUT_WAIT_IEOF;
break;
case CHAN_OUTPUT_WAIT_DRAIN:
debug("channel %d: OUTPUT_WAIT_DRAIN -> OUTPUT_CLOSED [write failed]", c->self);
chan_send_oclose(c);
c->ostate=CHAN_OUTPUT_CLOSED;
chan_delele_if_full_closed(c);
break;
default:
debug("internal error: chan_write_failed %d for ostate %d",c->self,c->ostate);
break;
}
}
void
chan_obuf_empty(Channel *c){
if(buffer_len(&c->output)){
debug("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_WAIT_DRAIN -> OUTPUT_CLOSED [obuf empty, send OCLOSE]", c->self);
chan_send_oclose(c);
c->ostate=CHAN_OUTPUT_CLOSED;
chan_delele_if_full_closed(c);
break;
default:
debug("internal error: chan_obuf_empty %d for ostate %d",c->self,c->ostate);
break;
}
}
/*
* ACTIONS: should never update c->istate or c->ostate
*/
static void
chan_send_ieof(Channel *c){
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:
debug("internal error: channel %d: cannot send IEOF for istate %d",c->self,c->istate);
break;
}
}
static void
chan_send_oclose(Channel *c){
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:
debug("internal error: channel %d: cannot send OCLOSE for ostate %d",c->self,c->istate);
break;
}
}
/* helper */
static void
chan_shutdown_write(Channel *c){
debug("channel %d: shutdown_write", c->self);
if(shutdown(c->sock, SHUT_WR)<0)
error("chan_shutdown_write failed for #%d/fd%d: %.100s",
c->self, c->sock, strerror(errno));
}
static void
chan_shutdown_read(Channel *c){
debug("channel %d: shutdown_read", c->self);
if(shutdown(c->sock, SHUT_RD)<0)
error("chan_shutdown_read failed for #%d/fd%d: %.100s",
c->self, c->sock, strerror(errno));
}
static void
chan_delele_if_full_closed(Channel *c){
if(c->istate==CHAN_INPUT_CLOSED && c->ostate==CHAN_OUTPUT_CLOSED){
debug("channel %d: closing", c->self);
channel_free(c->self);
}
}
void
chan_init_iostates(Channel *c){
c->ostate=CHAN_OUTPUT_OPEN;
c->istate=CHAN_INPUT_OPEN;
}
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