/*
- * Copyright (c) 1999 Markus Friedl. All rights reserved.
+ * Copyright (c) 1999, 2000, 2001 Markus Friedl. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
*/
#include "includes.h"
-RCSID("$OpenBSD: nchan.c,v 1.19 2000/09/07 20:27:52 deraadt Exp $");
-
-#include "ssh.h"
+RCSID("$OpenBSD: nchan.c,v 1.32 2001/10/10 22:18:47 markus Exp $");
+#include "ssh1.h"
+#include "ssh2.h"
#include "buffer.h"
#include "packet.h"
#include "channels.h"
-#include "nchan.h"
-
-#include "ssh2.h"
#include "compat.h"
+#include "log.h"
+
+/*
+ * SSH Protocol 1.5 aka New Channel Protocol
+ * Thanks to Martina, Axel and everyone who left Erlangen, leaving me bored.
+ * Written by Markus Friedl in October 1999
+ *
+ * Protocol versions 1.3 and 1.5 differ in the handshake protocol used for the
+ * tear down of channels:
+ *
+ * 1.3: strict request-ack-protocol:
+ * CLOSE ->
+ * <- CLOSE_CONFIRM
+ *
+ * 1.5: uses variations of:
+ * IEOF ->
+ * <- OCLOSE
+ * <- IEOF
+ * OCLOSE ->
+ * i.e. both sides have to close the channel
+ *
+ * 2.0: the EOF messages are optional
+ *
+ * See the debugging output from 'ssh -v' and 'sshd -d' of
+ * ssh-1.2.27 as an example.
+ *
+ */
/* functions manipulating channel states */
/*
/*
* ACTIONS: should never update the channel states
*/
-static void chan_send_ieof1(Channel *c);
-static void chan_send_oclose1(Channel *c);
-static void chan_send_close2(Channel *c);
-static void chan_send_eof2(Channel *c);
-
-/* channel cleanup */
-chan_event_fn *chan_delete_if_full_closed = NULL;
+static void chan_send_ieof1(Channel *);
+static void chan_send_oclose1(Channel *);
+static void chan_send_close2(Channel *);
+static void chan_send_eof2(Channel *);
/* helper */
-static void chan_shutdown_write(Channel *c);
-static void chan_shutdown_read(Channel *c);
+static void chan_shutdown_write(Channel *);
+static void chan_shutdown_read(Channel *);
/*
* SSH1 specific implementation of event functions
c->istate = CHAN_INPUT_CLOSED;
break;
default:
- error("channel %d: protocol error: chan_rcvd_oclose for istate %d",
+ error("channel %d: protocol error: rcvd_oclose for istate %d",
c->self, c->istate);
return;
}
debug("channel %d: input open -> drain", c->self);
chan_shutdown_read(c);
c->istate = CHAN_INPUT_WAIT_DRAIN;
+#if 0
if (buffer_len(&c->input) == 0) {
debug("channel %d: input: no drain shortcut", c->self);
chan_ibuf_empty(c);
}
+#endif
break;
default:
- error("channel %d: internal error: we do not read, but chan_read_failed for istate %d",
+ error("channel %d: chan_read_failed for istate %d",
c->self, c->istate);
break;
}
{
debug("channel %d: ibuf empty", c->self);
if (buffer_len(&c->input)) {
- error("channel %d: internal error: chan_ibuf_empty for non empty buffer",
+ error("channel %d: chan_ibuf_empty for non empty buffer",
c->self);
return;
}
c->istate = CHAN_INPUT_WAIT_OCLOSE;
break;
default:
- error("channel %d: internal error: chan_ibuf_empty for istate %d",
+ error("channel %d: chan_ibuf_empty for istate %d",
c->self, c->istate);
break;
}
if (c->type != SSH_CHANNEL_OPEN) {
debug("channel %d: non-open", c->self);
if (c->istate == CHAN_INPUT_OPEN) {
- debug("channel %d: non-open: input open -> wait_oclose", c->self);
+ debug("channel %d: non-open: input open -> wait_oclose",
+ c->self);
chan_shutdown_read(c);
chan_send_ieof1(c);
c->istate = CHAN_INPUT_WAIT_OCLOSE;
} else {
- error("channel %d: istate %d != open", c->self, c->istate);
+ error("channel %d: non-open: istate %d != open",
+ c->self, c->istate);
}
if (c->ostate == CHAN_OUTPUT_OPEN) {
- debug("channel %d: non-open: output open -> closed", c->self);
+ debug("channel %d: non-open: output open -> closed",
+ c->self);
chan_send_oclose1(c);
c->ostate = CHAN_OUTPUT_CLOSED;
} else {
- error("channel %d: ostate %d != open", c->self, c->ostate);
+ error("channel %d: non-open: ostate %d != open",
+ c->self, c->ostate);
}
return;
}
c->ostate = CHAN_OUTPUT_CLOSED;
break;
default:
- error("channel %d: protocol error: chan_rcvd_ieof for ostate %d",
+ error("channel %d: protocol error: rcvd_ieof for ostate %d",
c->self, c->ostate);
break;
}
c->ostate = CHAN_OUTPUT_CLOSED;
break;
default:
- error("channel %d: internal error: chan_write_failed for ostate %d",
+ error("channel %d: chan_write_failed for ostate %d",
c->self, c->ostate);
break;
}
{
debug("channel %d: obuf empty", c->self);
if (buffer_len(&c->output)) {
- error("channel %d: internal error: chan_obuf_empty for non empty buffer",
+ error("channel %d: chan_obuf_empty for non empty buffer",
c->self);
return;
}
c->ostate = CHAN_OUTPUT_CLOSED;
break;
default:
- error("channel %d: internal error: chan_obuf_empty for ostate %d",
+ error("channel %d: internal error: obuf_empty for ostate %d",
c->self, c->ostate);
break;
}
packet_send();
break;
default:
- error("channel %d: internal error: cannot send ieof for istate %d",
+ error("channel %d: cannot send ieof for istate %d",
c->self, c->istate);
break;
}
packet_send();
break;
default:
- error("channel %d: internal error: cannot send oclose for ostate %d",
+ error("channel %d: cannot send oclose for ostate %d",
c->self, c->ostate);
break;
}
}
-static void
-chan_delete_if_full_closed1(Channel *c)
-{
- if (c->istate == CHAN_INPUT_CLOSED && c->ostate == CHAN_OUTPUT_CLOSED) {
- debug("channel %d: full closed", c->self);
- channel_free(c->self);
- }
-}
/*
* the same for SSH2
}
switch (c->ostate) {
case CHAN_OUTPUT_OPEN:
- /* wait until a data from the channel is consumed if a CLOSE is received */
+ /*
+ * wait until a data from the channel is consumed if a CLOSE
+ * is received
+ */
debug("channel %d: output open -> drain", c->self);
c->ostate = CHAN_OUTPUT_WAIT_DRAIN;
break;
{
debug("channel %d: ibuf empty", c->self);
if (buffer_len(&c->input)) {
- error("channel %d: internal error: chan_ibuf_empty for non empty buffer",
+ error("channel %d: chan_ibuf_empty for non empty buffer",
c->self);
return;
}
c->istate = CHAN_INPUT_CLOSED;
break;
default:
- error("channel %d: internal error: chan_ibuf_empty for istate %d",
+ error("channel %d: chan_ibuf_empty for istate %d",
c->self, c->istate);
break;
}
c->ostate = CHAN_OUTPUT_CLOSED;
break;
default:
- error("channel %d: internal error: chan_write_failed for ostate %d",
+ error("channel %d: chan_write_failed for ostate %d",
c->self, c->ostate);
break;
}
{
debug("channel %d: obuf empty", c->self);
if (buffer_len(&c->output)) {
- error("internal error: chan_obuf_empty %d for non empty buffer",
+ error("channel %d: chan_obuf_empty for non empty buffer",
c->self);
return;
}
c->ostate = CHAN_OUTPUT_CLOSED;
break;
default:
- error("channel %d: internal error: chan_obuf_empty for ostate %d",
+ error("channel %d: chan_obuf_empty for ostate %d",
c->self, c->ostate);
break;
}
packet_send();
break;
default:
- error("channel %d: internal error: cannot send eof for istate %d",
+ error("channel %d: cannot send eof for istate %d",
c->self, c->istate);
break;
}
debug("channel %d: send close", c->self);
if (c->ostate != CHAN_OUTPUT_CLOSED ||
c->istate != CHAN_INPUT_CLOSED) {
- error("channel %d: internal error: cannot send close for istate/ostate %d/%d",
+ error("channel %d: cannot send close for istate/ostate %d/%d",
c->self, c->istate, c->ostate);
} else if (c->flags & CHAN_CLOSE_SENT) {
- error("channel %d: internal error: already sent close", c->self);
+ error("channel %d: already sent close", c->self);
} else {
packet_start(SSH2_MSG_CHANNEL_CLOSE);
packet_put_int(c->remote_id);
c->flags |= CHAN_CLOSE_SENT;
}
}
-static void
-chan_delete_if_full_closed2(Channel *c)
+
+/* shared */
+
+void
+chan_mark_dead(Channel *c)
+{
+ c->type = SSH_CHANNEL_ZOMBIE;
+}
+
+int
+chan_is_dead(Channel *c, int send)
{
- if (c->istate == CHAN_INPUT_CLOSED && c->ostate == CHAN_OUTPUT_CLOSED) {
+ if (c->type == SSH_CHANNEL_ZOMBIE) {
+ debug("channel %d: zombie", c->self);
+ return 1;
+ }
+ if (c->istate != CHAN_INPUT_CLOSED || c->ostate != CHAN_OUTPUT_CLOSED)
+ return 0;
+ if (!compat20) {
+ debug("channel %d: is dead", c->self);
+ return 1;
+ }
+ /*
+ * we have to delay the close message if the efd (for stderr) is
+ * still active
+ */
+ if (((c->extended_usage != CHAN_EXTENDED_IGNORE) &&
+ buffer_len(&c->extended) > 0)
+#if 0
+ || ((c->extended_usage == CHAN_EXTENDED_READ) &&
+ c->efd != -1)
+#endif
+ ) {
+ debug2("channel %d: active efd: %d len %d type %s",
+ c->self, c->efd, buffer_len(&c->extended),
+ c->extended_usage==CHAN_EXTENDED_READ ?
+ "read": "write");
+ } else {
if (!(c->flags & CHAN_CLOSE_SENT)) {
- chan_send_close2(c);
+ if (send) {
+ chan_send_close2(c);
+ } else {
+ /* channel would be dead if we sent a close */
+ if (c->flags & CHAN_CLOSE_RCVD) {
+ debug("channel %d: almost dead",
+ c->self);
+ return 1;
+ }
+ }
}
if ((c->flags & CHAN_CLOSE_SENT) &&
(c->flags & CHAN_CLOSE_RCVD)) {
- debug("channel %d: full closed2", c->self);
- channel_free(c->self);
+ debug("channel %d: is dead", c->self);
+ return 1;
}
}
+ return 0;
}
-/* shared */
void
chan_init_iostates(Channel *c)
{
chan_rcvd_ieof = chan_rcvd_ieof2;
chan_write_failed = chan_write_failed2;
chan_obuf_empty = chan_obuf_empty2;
-
- chan_delete_if_full_closed = chan_delete_if_full_closed2;
} else {
chan_rcvd_oclose = chan_rcvd_oclose1;
chan_read_failed = chan_read_failed_12;
chan_rcvd_ieof = chan_rcvd_ieof1;
chan_write_failed = chan_write_failed1;
chan_obuf_empty = chan_obuf_empty1;
-
- chan_delete_if_full_closed = chan_delete_if_full_closed1;
}
}
debug("channel %d: close_write", c->self);
if (c->sock != -1) {
if (shutdown(c->sock, SHUT_WR) < 0)
- debug("channel %d: chan_shutdown_write: shutdown() failed for fd%d: %.100s",
+ debug("channel %d: chan_shutdown_write: "
+ "shutdown() failed for fd%d: %.100s",
c->self, c->sock, strerror(errno));
} else {
- if (close(c->wfd) < 0)
- log("channel %d: chan_shutdown_write: close() failed for fd%d: %.100s",
+ if (channel_close_fd(&c->wfd) < 0)
+ log("channel %d: chan_shutdown_write: "
+ "close() failed for fd%d: %.100s",
c->self, c->wfd, strerror(errno));
- c->wfd = -1;
}
}
static void
return;
debug("channel %d: close_read", c->self);
if (c->sock != -1) {
- /*
+ /*
* shutdown(sock, SHUT_READ) may return ENOTCONN if the
* write side has been closed already. (bug on Linux)
+ * HP-UX may return ENOTCONN also.
*/
if (shutdown(c->sock, SHUT_RD) < 0
- && (errno != ENOTCONN
- || c->ostate == CHAN_OUTPUT_OPEN
- || c->ostate == CHAN_OUTPUT_WAIT_DRAIN))
- error("channel %d: chan_shutdown_read: shutdown() failed for fd%d [i%d o%d]: %.100s",
- c->self, c->sock, c->istate, c->ostate, strerror(errno));
+ && errno != ENOTCONN)
+ error("channel %d: chan_shutdown_read: "
+ "shutdown() failed for fd%d [i%d o%d]: %.100s",
+ c->self, c->sock, c->istate, c->ostate,
+ strerror(errno));
} else {
- if (close(c->rfd) < 0)
- log("channel %d: chan_shutdown_read: close() failed for fd%d: %.100s",
+ if (channel_close_fd(&c->rfd) < 0)
+ log("channel %d: chan_shutdown_read: "
+ "close() failed for fd%d: %.100s",
c->self, c->rfd, strerror(errno));
- c->rfd = -1;
}
}
andersk / openssh.git / blobdiff