2 * Copyright (c) 1999 Markus Friedl. All rights reserved.
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
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.
12 * 3. All advertising materials mentioning features or use of this software
13 * must display the following acknowledgement:
14 * This product includes software developed by Markus Friedl.
15 * 4. The name of the author may not be used to endorse or promote products
16 * derived from this software without specific prior written permission.
18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
19 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
20 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
21 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
22 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
23 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
24 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
25 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
27 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
40 static void chan_send_ieof(Channel *c);
41 static void chan_send_oclose(Channel *c);
42 static void chan_shutdown_write(Channel *c);
43 static void chan_shutdown_read(Channel *c);
44 static void chan_delele_if_full_closed(Channel *c);
47 * EVENTS update channel input/output states execute ACTIONS
50 /* events concerning the INPUT from socket for channel (istate) */
52 chan_rcvd_oclose(Channel *c)
55 case CHAN_INPUT_WAIT_OCLOSE:
56 debug("channel %d: INPUT_WAIT_OCLOSE -> INPUT_CLOSED [rcvd OCLOSE]", c->self);
57 c->istate = CHAN_INPUT_CLOSED;
58 chan_delele_if_full_closed(c);
61 debug("channel %d: INPUT_OPEN -> INPUT_CLOSED [rvcd OCLOSE, send IEOF]", c->self);
62 chan_shutdown_read(c);
64 c->istate = CHAN_INPUT_CLOSED;
65 chan_delele_if_full_closed(c);
68 error("protocol error: chan_rcvd_oclose %d for istate %d", c->self, c->istate);
73 chan_read_failed(Channel *c)
77 debug("channel %d: INPUT_OPEN -> INPUT_WAIT_DRAIN [read failed]", c->self);
78 chan_shutdown_read(c);
79 c->istate = CHAN_INPUT_WAIT_DRAIN;
82 error("internal error: we do not read, but chan_read_failed %d for istate %d",
88 chan_ibuf_empty(Channel *c)
90 if (buffer_len(&c->input)) {
91 error("internal error: chan_ibuf_empty %d for non empty buffer", c->self);
95 case CHAN_INPUT_WAIT_DRAIN:
96 debug("channel %d: INPUT_WAIT_DRAIN -> INPUT_WAIT_OCLOSE [inbuf empty, send IEOF]", c->self);
98 c->istate = CHAN_INPUT_WAIT_OCLOSE;
101 error("internal error: chan_ibuf_empty %d for istate %d", c->self, c->istate);
106 /* events concerning the OUTPUT from channel for socket (ostate) */
108 chan_rcvd_ieof(Channel *c)
111 case CHAN_OUTPUT_OPEN:
112 debug("channel %d: OUTPUT_OPEN -> OUTPUT_WAIT_DRAIN [rvcd IEOF]", c->self);
113 c->ostate = CHAN_OUTPUT_WAIT_DRAIN;
115 case CHAN_OUTPUT_WAIT_IEOF:
116 debug("channel %d: OUTPUT_WAIT_IEOF -> OUTPUT_CLOSED [rvcd IEOF]", c->self);
117 c->ostate = CHAN_OUTPUT_CLOSED;
118 chan_delele_if_full_closed(c);
121 error("protocol error: chan_rcvd_ieof %d for ostate %d", c->self, c->ostate);
126 chan_write_failed(Channel *c)
129 case CHAN_OUTPUT_OPEN:
130 debug("channel %d: OUTPUT_OPEN -> OUTPUT_WAIT_IEOF [write failed]", c->self);
132 c->ostate = CHAN_OUTPUT_WAIT_IEOF;
134 case CHAN_OUTPUT_WAIT_DRAIN:
135 debug("channel %d: OUTPUT_WAIT_DRAIN -> OUTPUT_CLOSED [write failed]", c->self);
137 c->ostate = CHAN_OUTPUT_CLOSED;
138 chan_delele_if_full_closed(c);
141 error("internal error: chan_write_failed %d for ostate %d", c->self, c->ostate);
146 chan_obuf_empty(Channel *c)
148 if (buffer_len(&c->output)) {
149 debug("internal error: chan_obuf_empty %d for non empty buffer", c->self);
153 case CHAN_OUTPUT_WAIT_DRAIN:
154 debug("channel %d: OUTPUT_WAIT_DRAIN -> OUTPUT_CLOSED [obuf empty, send OCLOSE]", c->self);
156 c->ostate = CHAN_OUTPUT_CLOSED;
157 chan_delele_if_full_closed(c);
160 error("internal error: chan_obuf_empty %d for ostate %d", c->self, c->ostate);
166 * ACTIONS: should never update the channel states: c->istate or c->ostate
169 chan_send_ieof(Channel *c)
172 case CHAN_INPUT_OPEN:
173 case CHAN_INPUT_WAIT_DRAIN:
174 packet_start(SSH_MSG_CHANNEL_INPUT_EOF);
175 packet_put_int(c->remote_id);
179 error("internal error: channel %d: cannot send IEOF for istate %d", c->self, c->istate);
184 chan_send_oclose(Channel *c)
187 case CHAN_OUTPUT_OPEN:
188 case CHAN_OUTPUT_WAIT_DRAIN:
189 chan_shutdown_write(c);
190 buffer_consume(&c->output, buffer_len(&c->output));
191 packet_start(SSH_MSG_CHANNEL_OUTPUT_CLOSE);
192 packet_put_int(c->remote_id);
196 error("internal error: channel %d: cannot send OCLOSE for ostate %d", c->self, c->istate);
203 chan_shutdown_write(Channel *c)
205 /* shutdown failure is allowed if write failed already */
206 debug("channel %d: shutdown_write", c->self);
207 if (shutdown(c->sock, SHUT_WR) < 0)
208 debug("chan_shutdown_write failed for #%d/fd%d: %.100s",
209 c->self, c->sock, strerror(errno));
212 chan_shutdown_read(Channel *c)
214 debug("channel %d: shutdown_read", c->self);
215 if (shutdown(c->sock, SHUT_RD) < 0)
216 error("chan_shutdown_read failed for #%d/fd%d: %.100s",
217 c->self, c->sock, strerror(errno));
220 chan_delele_if_full_closed(Channel *c)
222 if (c->istate == CHAN_INPUT_CLOSED && c->ostate == CHAN_OUTPUT_CLOSED) {
223 debug("channel %d: closing", c->self);
224 channel_free(c->self);
228 chan_init_iostates(Channel *c)
230 c->ostate = CHAN_OUTPUT_OPEN;
231 c->istate = CHAN_INPUT_OPEN;