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.
31 RCSID("$OpenBSD: nchan.c,v 1.18 2000/06/20 01:39:42 markus Exp $");
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;
110 if (buffer_len(&c->input) == 0) {
111 debug("channel %d: input: no drain shortcut", c->self);
116 error("channel %d: internal error: we do not read, but chan_read_failed for istate %d",
122 chan_ibuf_empty1(Channel *c)
124 debug("channel %d: ibuf empty", c->self);
125 if (buffer_len(&c->input)) {
126 error("channel %d: internal error: chan_ibuf_empty for non empty buffer",
131 case CHAN_INPUT_WAIT_DRAIN:
132 debug("channel %d: input drain -> wait_oclose", c->self);
134 c->istate = CHAN_INPUT_WAIT_OCLOSE;
137 error("channel %d: internal error: chan_ibuf_empty for istate %d",
143 chan_rcvd_ieof1(Channel *c)
145 debug("channel %d: rcvd ieof", c->self);
146 if (c->type != SSH_CHANNEL_OPEN) {
147 debug("channel %d: non-open", c->self);
148 if (c->istate == CHAN_INPUT_OPEN) {
149 debug("channel %d: non-open: input open -> wait_oclose", c->self);
150 chan_shutdown_read(c);
152 c->istate = CHAN_INPUT_WAIT_OCLOSE;
154 error("channel %d: istate %d != open", c->self, c->istate);
156 if (c->ostate == CHAN_OUTPUT_OPEN) {
157 debug("channel %d: non-open: output open -> closed", c->self);
158 chan_send_oclose1(c);
159 c->ostate = CHAN_OUTPUT_CLOSED;
161 error("channel %d: ostate %d != open", c->self, c->ostate);
166 case CHAN_OUTPUT_OPEN:
167 debug("channel %d: output open -> drain", c->self);
168 c->ostate = CHAN_OUTPUT_WAIT_DRAIN;
170 case CHAN_OUTPUT_WAIT_IEOF:
171 debug("channel %d: output wait_ieof -> closed", c->self);
172 c->ostate = CHAN_OUTPUT_CLOSED;
175 error("channel %d: protocol error: chan_rcvd_ieof for ostate %d",
181 chan_write_failed1(Channel *c)
183 debug("channel %d: write failed", c->self);
185 case CHAN_OUTPUT_OPEN:
186 debug("channel %d: output open -> wait_ieof", c->self);
187 chan_send_oclose1(c);
188 c->ostate = CHAN_OUTPUT_WAIT_IEOF;
190 case CHAN_OUTPUT_WAIT_DRAIN:
191 debug("channel %d: output wait_drain -> closed", c->self);
192 chan_send_oclose1(c);
193 c->ostate = CHAN_OUTPUT_CLOSED;
196 error("channel %d: internal error: chan_write_failed for ostate %d",
202 chan_obuf_empty1(Channel *c)
204 debug("channel %d: obuf empty", c->self);
205 if (buffer_len(&c->output)) {
206 error("channel %d: internal error: chan_obuf_empty for non empty buffer",
211 case CHAN_OUTPUT_WAIT_DRAIN:
212 debug("channel %d: output drain -> closed", c->self);
213 chan_send_oclose1(c);
214 c->ostate = CHAN_OUTPUT_CLOSED;
217 error("channel %d: internal error: chan_obuf_empty for ostate %d",
223 chan_send_ieof1(Channel *c)
225 debug("channel %d: send ieof", c->self);
227 case CHAN_INPUT_OPEN:
228 case CHAN_INPUT_WAIT_DRAIN:
229 packet_start(SSH_MSG_CHANNEL_INPUT_EOF);
230 packet_put_int(c->remote_id);
234 error("channel %d: internal error: cannot send ieof for istate %d",
240 chan_send_oclose1(Channel *c)
242 debug("channel %d: send oclose", c->self);
244 case CHAN_OUTPUT_OPEN:
245 case CHAN_OUTPUT_WAIT_DRAIN:
246 chan_shutdown_write(c);
247 buffer_consume(&c->output, buffer_len(&c->output));
248 packet_start(SSH_MSG_CHANNEL_OUTPUT_CLOSE);
249 packet_put_int(c->remote_id);
253 error("channel %d: internal error: cannot send oclose for ostate %d",
259 chan_delete_if_full_closed1(Channel *c)
261 if (c->istate == CHAN_INPUT_CLOSED && c->ostate == CHAN_OUTPUT_CLOSED) {
262 debug("channel %d: full closed", c->self);
263 channel_free(c->self);
271 chan_rcvd_oclose2(Channel *c)
273 debug("channel %d: rcvd close", c->self);
274 if (c->flags & CHAN_CLOSE_RCVD)
275 error("channel %d: protocol error: close rcvd twice", c->self);
276 c->flags |= CHAN_CLOSE_RCVD;
277 if (c->type == SSH_CHANNEL_LARVAL) {
278 /* tear down larval channels immediately */
279 c->ostate = CHAN_OUTPUT_CLOSED;
280 c->istate = CHAN_INPUT_CLOSED;
284 case CHAN_OUTPUT_OPEN:
285 /* wait until a data from the channel is consumed if a CLOSE is received */
286 debug("channel %d: output open -> drain", c->self);
287 c->ostate = CHAN_OUTPUT_WAIT_DRAIN;
291 case CHAN_INPUT_OPEN:
292 debug("channel %d: input open -> closed", c->self);
293 chan_shutdown_read(c);
295 case CHAN_INPUT_WAIT_DRAIN:
296 debug("channel %d: input drain -> closed", c->self);
300 c->istate = CHAN_INPUT_CLOSED;
303 chan_ibuf_empty2(Channel *c)
305 debug("channel %d: ibuf empty", c->self);
306 if (buffer_len(&c->input)) {
307 error("channel %d: internal error: chan_ibuf_empty for non empty buffer",
312 case CHAN_INPUT_WAIT_DRAIN:
313 debug("channel %d: input drain -> closed", c->self);
314 if (!(c->flags & CHAN_CLOSE_SENT))
316 c->istate = CHAN_INPUT_CLOSED;
319 error("channel %d: internal error: chan_ibuf_empty for istate %d",
325 chan_rcvd_ieof2(Channel *c)
327 debug("channel %d: rcvd eof", c->self);
328 if (c->ostate == CHAN_OUTPUT_OPEN) {
329 debug("channel %d: output open -> drain", c->self);
330 c->ostate = CHAN_OUTPUT_WAIT_DRAIN;
334 chan_write_failed2(Channel *c)
336 debug("channel %d: write failed", c->self);
338 case CHAN_OUTPUT_OPEN:
339 debug("channel %d: output open -> closed", c->self);
340 chan_shutdown_write(c); /* ?? */
341 c->ostate = CHAN_OUTPUT_CLOSED;
343 case CHAN_OUTPUT_WAIT_DRAIN:
344 debug("channel %d: output drain -> closed", c->self);
345 chan_shutdown_write(c);
346 c->ostate = CHAN_OUTPUT_CLOSED;
349 error("channel %d: internal error: chan_write_failed for ostate %d",
355 chan_obuf_empty2(Channel *c)
357 debug("channel %d: obuf empty", c->self);
358 if (buffer_len(&c->output)) {
359 error("internal error: chan_obuf_empty %d for non empty buffer",
364 case CHAN_OUTPUT_WAIT_DRAIN:
365 debug("channel %d: output drain -> closed", c->self);
366 chan_shutdown_write(c);
367 c->ostate = CHAN_OUTPUT_CLOSED;
370 error("channel %d: internal error: chan_obuf_empty for ostate %d",
376 chan_send_eof2(Channel *c)
378 debug("channel %d: send eof", c->self);
380 case CHAN_INPUT_WAIT_DRAIN:
381 packet_start(SSH2_MSG_CHANNEL_EOF);
382 packet_put_int(c->remote_id);
386 error("channel %d: internal error: cannot send eof for istate %d",
392 chan_send_close2(Channel *c)
394 debug("channel %d: send close", c->self);
395 if (c->ostate != CHAN_OUTPUT_CLOSED ||
396 c->istate != CHAN_INPUT_CLOSED) {
397 error("channel %d: internal error: cannot send close for istate/ostate %d/%d",
398 c->self, c->istate, c->ostate);
399 } else if (c->flags & CHAN_CLOSE_SENT) {
400 error("channel %d: internal error: already sent close", c->self);
402 packet_start(SSH2_MSG_CHANNEL_CLOSE);
403 packet_put_int(c->remote_id);
405 c->flags |= CHAN_CLOSE_SENT;
409 chan_delete_if_full_closed2(Channel *c)
411 if (c->istate == CHAN_INPUT_CLOSED && c->ostate == CHAN_OUTPUT_CLOSED) {
412 if (!(c->flags & CHAN_CLOSE_SENT)) {
415 if ((c->flags & CHAN_CLOSE_SENT) &&
416 (c->flags & CHAN_CLOSE_RCVD)) {
417 debug("channel %d: full closed2", c->self);
418 channel_free(c->self);
425 chan_init_iostates(Channel *c)
427 c->ostate = CHAN_OUTPUT_OPEN;
428 c->istate = CHAN_INPUT_OPEN;
437 chan_rcvd_oclose = chan_rcvd_oclose2;
438 chan_read_failed = chan_read_failed_12;
439 chan_ibuf_empty = chan_ibuf_empty2;
441 chan_rcvd_ieof = chan_rcvd_ieof2;
442 chan_write_failed = chan_write_failed2;
443 chan_obuf_empty = chan_obuf_empty2;
445 chan_delete_if_full_closed = chan_delete_if_full_closed2;
447 chan_rcvd_oclose = chan_rcvd_oclose1;
448 chan_read_failed = chan_read_failed_12;
449 chan_ibuf_empty = chan_ibuf_empty1;
451 chan_rcvd_ieof = chan_rcvd_ieof1;
452 chan_write_failed = chan_write_failed1;
453 chan_obuf_empty = chan_obuf_empty1;
455 chan_delete_if_full_closed = chan_delete_if_full_closed1;
461 chan_shutdown_write(Channel *c)
463 buffer_consume(&c->output, buffer_len(&c->output));
464 if (compat20 && c->type == SSH_CHANNEL_LARVAL)
466 /* shutdown failure is allowed if write failed already */
467 debug("channel %d: close_write", c->self);
469 if (shutdown(c->sock, SHUT_WR) < 0)
470 debug("channel %d: chan_shutdown_write: shutdown() failed for fd%d: %.100s",
471 c->self, c->sock, strerror(errno));
473 if (close(c->wfd) < 0)
474 log("channel %d: chan_shutdown_write: close() failed for fd%d: %.100s",
475 c->self, c->wfd, strerror(errno));
480 chan_shutdown_read(Channel *c)
482 if (compat20 && c->type == SSH_CHANNEL_LARVAL)
484 debug("channel %d: close_read", c->self);
486 if (shutdown(c->sock, SHUT_RD) < 0)
487 error("channel %d: chan_shutdown_read: shutdown() failed for fd%d [i%d o%d]: %.100s",
488 c->self, c->sock, c->istate, c->ostate, strerror(errno));
490 if (close(c->rfd) < 0)
491 log("channel %d: chan_shutdown_read: close() failed for fd%d: %.100s",
492 c->self, c->rfd, strerror(errno));