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.
43 /* functions manipulating channel states */
45 * EVENTS update channel input/output states execute ACTIONS
47 /* events concerning the INPUT from socket for channel (istate) */
48 chan_event_fn *chan_rcvd_oclose = NULL;
49 chan_event_fn *chan_read_failed = NULL;
50 chan_event_fn *chan_ibuf_empty = NULL;
51 /* events concerning the OUTPUT from channel for socket (ostate) */
52 chan_event_fn *chan_rcvd_ieof = NULL;
53 chan_event_fn *chan_write_failed = NULL;
54 chan_event_fn *chan_obuf_empty = NULL;
56 * ACTIONS: should never update the channel states
58 static void chan_send_ieof1(Channel *c);
59 static void chan_send_oclose1(Channel *c);
60 static void chan_send_close2(Channel *c);
61 static void chan_send_eof2(Channel *c);
64 chan_event_fn *chan_delete_if_full_closed = NULL;
67 static void chan_shutdown_write(Channel *c);
68 static void chan_shutdown_read(Channel *c);
71 * SSH1 specific implementation of event functions
75 chan_rcvd_oclose1(Channel *c)
77 debug("channel %d: rcvd oclose", c->self);
79 case CHAN_INPUT_WAIT_OCLOSE:
80 debug("channel %d: input wait_oclose -> closed", c->self);
81 c->istate = CHAN_INPUT_CLOSED;
84 debug("channel %d: input open -> closed", c->self);
85 chan_shutdown_read(c);
87 c->istate = CHAN_INPUT_CLOSED;
89 case CHAN_INPUT_WAIT_DRAIN:
90 /* both local read_failed and remote write_failed */
91 log("channel %d: input drain -> closed", c->self);
93 c->istate = CHAN_INPUT_CLOSED;
96 error("channel %d: protocol error: chan_rcvd_oclose for istate %d",
102 chan_read_failed_12(Channel *c)
104 debug("channel %d: read failed", c->self);
106 case CHAN_INPUT_OPEN:
107 debug("channel %d: input open -> drain", c->self);
108 chan_shutdown_read(c);
109 c->istate = CHAN_INPUT_WAIT_DRAIN;
112 error("channel %d: internal error: we do not read, but chan_read_failed for istate %d",
118 chan_ibuf_empty1(Channel *c)
120 debug("channel %d: ibuf empty", c->self);
121 if (buffer_len(&c->input)) {
122 error("channel %d: internal error: chan_ibuf_empty for non empty buffer",
127 case CHAN_INPUT_WAIT_DRAIN:
128 debug("channel %d: input drain -> wait_oclose", c->self);
130 c->istate = CHAN_INPUT_WAIT_OCLOSE;
133 error("channel %d: internal error: chan_ibuf_empty for istate %d",
139 chan_rcvd_ieof1(Channel *c)
141 debug("channel %d: rcvd ieof", c->self);
143 case CHAN_OUTPUT_OPEN:
144 debug("channel %d: output open -> drain", c->self);
145 c->ostate = CHAN_OUTPUT_WAIT_DRAIN;
147 case CHAN_OUTPUT_WAIT_IEOF:
148 debug("channel %d: output wait_ieof -> closed", c->self);
149 c->ostate = CHAN_OUTPUT_CLOSED;
152 error("channel %d: protocol error: chan_rcvd_ieof for ostate %d",
158 chan_write_failed1(Channel *c)
160 debug("channel %d: write failed", c->self);
162 case CHAN_OUTPUT_OPEN:
163 debug("channel %d: output open -> wait_ieof", c->self);
164 chan_send_oclose1(c);
165 c->ostate = CHAN_OUTPUT_WAIT_IEOF;
167 case CHAN_OUTPUT_WAIT_DRAIN:
168 debug("channel %d: output wait_drain -> closed", c->self);
169 chan_send_oclose1(c);
170 c->ostate = CHAN_OUTPUT_CLOSED;
173 error("channel %d: internal error: chan_write_failed for ostate %d",
179 chan_obuf_empty1(Channel *c)
181 debug("channel %d: obuf empty", c->self);
182 if (buffer_len(&c->output)) {
183 error("channel %d: internal error: chan_obuf_empty for non empty buffer",
188 case CHAN_OUTPUT_WAIT_DRAIN:
189 debug("channel %d: output drain -> closed", c->self);
190 chan_send_oclose1(c);
191 c->ostate = CHAN_OUTPUT_CLOSED;
194 error("channel %d: internal error: chan_obuf_empty for ostate %d",
200 chan_send_ieof1(Channel *c)
202 debug("channel %d: send ieof", c->self);
204 case CHAN_INPUT_OPEN:
205 case CHAN_INPUT_WAIT_DRAIN:
206 packet_start(SSH_MSG_CHANNEL_INPUT_EOF);
207 packet_put_int(c->remote_id);
211 error("channel %d: internal error: cannot send ieof for istate %d",
217 chan_send_oclose1(Channel *c)
219 debug("channel %d: send oclose", c->self);
221 case CHAN_OUTPUT_OPEN:
222 case CHAN_OUTPUT_WAIT_DRAIN:
223 chan_shutdown_write(c);
224 buffer_consume(&c->output, buffer_len(&c->output));
225 packet_start(SSH_MSG_CHANNEL_OUTPUT_CLOSE);
226 packet_put_int(c->remote_id);
230 error("channel %d: internal error: cannot send oclose for ostate %d",
236 chan_delete_if_full_closed1(Channel *c)
238 if (c->istate == CHAN_INPUT_CLOSED && c->ostate == CHAN_OUTPUT_CLOSED) {
239 debug("channel %d: full closed", c->self);
240 channel_free(c->self);
248 chan_rcvd_oclose2(Channel *c)
250 debug("channel %d: rcvd close", c->self);
251 if (c->flags & CHAN_CLOSE_RCVD)
252 error("channel %d: protocol error: close rcvd twice", c->self);
253 c->flags |= CHAN_CLOSE_RCVD;
254 if (c->type == SSH_CHANNEL_LARVAL) {
255 /* tear down larval channels immediately */
256 c->ostate = CHAN_OUTPUT_CLOSED;
257 c->istate = CHAN_INPUT_CLOSED;
261 case CHAN_OUTPUT_OPEN:
262 /* wait until a data from the channel is consumed if a CLOSE is received */
263 debug("channel %d: output open -> drain", c->self);
264 c->ostate = CHAN_OUTPUT_WAIT_DRAIN;
268 case CHAN_INPUT_OPEN:
269 debug("channel %d: input open -> closed", c->self);
270 chan_shutdown_read(c);
272 case CHAN_INPUT_WAIT_DRAIN:
273 debug("channel %d: input drain -> closed", c->self);
277 c->istate = CHAN_INPUT_CLOSED;
280 chan_ibuf_empty2(Channel *c)
282 debug("channel %d: ibuf empty", c->self);
283 if (buffer_len(&c->input)) {
284 error("channel %d: internal error: chan_ibuf_empty for non empty buffer",
289 case CHAN_INPUT_WAIT_DRAIN:
290 debug("channel %d: input drain -> closed", c->self);
291 if (!(c->flags & CHAN_CLOSE_SENT))
293 c->istate = CHAN_INPUT_CLOSED;
296 error("channel %d: internal error: chan_ibuf_empty for istate %d",
302 chan_rcvd_ieof2(Channel *c)
304 debug("channel %d: rcvd eof", c->self);
305 if (c->ostate == CHAN_OUTPUT_OPEN) {
306 debug("channel %d: output open -> drain", c->self);
307 c->ostate = CHAN_OUTPUT_WAIT_DRAIN;
311 chan_write_failed2(Channel *c)
313 debug("channel %d: write failed", c->self);
315 case CHAN_OUTPUT_OPEN:
316 debug("channel %d: output open -> closed", c->self);
317 chan_shutdown_write(c); // ??
318 c->ostate = CHAN_OUTPUT_CLOSED;
320 case CHAN_OUTPUT_WAIT_DRAIN:
321 debug("channel %d: output drain -> closed", c->self);
322 chan_shutdown_write(c);
323 c->ostate = CHAN_OUTPUT_CLOSED;
326 error("channel %d: internal error: chan_write_failed for ostate %d",
332 chan_obuf_empty2(Channel *c)
334 debug("channel %d: obuf empty", c->self);
335 if (buffer_len(&c->output)) {
336 error("internal error: chan_obuf_empty %d for non empty buffer",
341 case CHAN_OUTPUT_WAIT_DRAIN:
342 debug("channel %d: output drain -> closed", c->self);
343 chan_shutdown_write(c);
344 c->ostate = CHAN_OUTPUT_CLOSED;
347 error("channel %d: internal error: chan_obuf_empty for ostate %d",
353 chan_send_eof2(Channel *c)
355 debug("channel %d: send eof", c->self);
357 case CHAN_INPUT_WAIT_DRAIN:
358 packet_start(SSH2_MSG_CHANNEL_EOF);
359 packet_put_int(c->remote_id);
363 error("channel %d: internal error: cannot send eof for istate %d",
369 chan_send_close2(Channel *c)
371 debug("channel %d: send close", c->self);
372 if (c->ostate != CHAN_OUTPUT_CLOSED ||
373 c->istate != CHAN_INPUT_CLOSED) {
374 error("channel %d: internal error: cannot send close for istate/ostate %d/%d",
375 c->self, c->istate, c->ostate);
376 } else if (c->flags & CHAN_CLOSE_SENT) {
377 error("channel %d: internal error: already sent close", c->self);
379 packet_start(SSH2_MSG_CHANNEL_CLOSE);
380 packet_put_int(c->remote_id);
382 c->flags |= CHAN_CLOSE_SENT;
386 chan_delete_if_full_closed2(Channel *c)
388 if (c->istate == CHAN_INPUT_CLOSED && c->ostate == CHAN_OUTPUT_CLOSED) {
389 if (!(c->flags & CHAN_CLOSE_SENT)) {
392 if ((c->flags & CHAN_CLOSE_SENT) &&
393 (c->flags & CHAN_CLOSE_RCVD)) {
394 debug("channel %d: full closed2", c->self);
395 channel_free(c->self);
402 chan_init_iostates(Channel *c)
404 c->ostate = CHAN_OUTPUT_OPEN;
405 c->istate = CHAN_INPUT_OPEN;
414 chan_rcvd_oclose = chan_rcvd_oclose2;
415 chan_read_failed = chan_read_failed_12;
416 chan_ibuf_empty = chan_ibuf_empty2;
418 chan_rcvd_ieof = chan_rcvd_ieof2;
419 chan_write_failed = chan_write_failed2;
420 chan_obuf_empty = chan_obuf_empty2;
422 chan_delete_if_full_closed = chan_delete_if_full_closed2;
424 chan_rcvd_oclose = chan_rcvd_oclose1;
425 chan_read_failed = chan_read_failed_12;
426 chan_ibuf_empty = chan_ibuf_empty1;
428 chan_rcvd_ieof = chan_rcvd_ieof1;
429 chan_write_failed = chan_write_failed1;
430 chan_obuf_empty = chan_obuf_empty1;
432 chan_delete_if_full_closed = chan_delete_if_full_closed1;
438 chan_shutdown_write(Channel *c)
440 buffer_consume(&c->output, buffer_len(&c->output));
441 if (compat20 && c->type == SSH_CHANNEL_LARVAL)
443 /* shutdown failure is allowed if write failed already */
444 debug("channel %d: close_write", c->self);
446 if (shutdown(c->sock, SHUT_WR) < 0)
447 debug("channel %d: chan_shutdown_write: shutdown() failed for fd%d: %.100s",
448 c->self, c->sock, strerror(errno));
450 if (close(c->wfd) < 0)
451 log("channel %d: chan_shutdown_write: close() failed for fd%d: %.100s",
452 c->self, c->wfd, strerror(errno));
457 chan_shutdown_read(Channel *c)
459 if (compat20 && c->type == SSH_CHANNEL_LARVAL)
461 debug("channel %d: close_read", c->self);
463 if (shutdown(c->sock, SHUT_RD) < 0)
464 error("channel %d: chan_shutdown_read: shutdown() failed for fd%d [i%d o%d]: %.100s",
465 c->self, c->sock, c->istate, c->ostate, strerror(errno));
467 if (close(c->rfd) < 0)
468 log("channel %d: chan_shutdown_read: close() failed for fd%d: %.100s",
469 c->self, c->rfd, strerror(errno));