diff options
Diffstat (limited to 'nchan.c')
| -rw-r--r-- | nchan.c | 187 |
1 files changed, 187 insertions, 0 deletions
diff --git a/nchan.c b/nchan.c new file mode 100644 index 00000000..fcaeae40 --- /dev/null +++ b/nchan.c @@ -0,0 +1,187 @@ +#include "includes.h" +RCSID("$Id: nchan.c,v 1.1 1999/10/27 03:42:44 damien 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; +} |